SPARC

Gene Summary

Gene:SPARC; secreted protein acidic and cysteine rich
Aliases: ON, OI17, BM-40
Location:5q33.1
Summary:This gene encodes a cysteine-rich acidic matrix-associated protein. The encoded protein is required for the collagen in bone to become calcified but is also involved in extracellular matrix synthesis and promotion of changes to cell shape. The gene product has been associated with tumor suppression but has also been correlated with metastasis based on changes to cell shape which can promote tumor cell invasion. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2015]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:SPARC
Source:NCBIAccessed: 01 September, 2019

Ontology:

What does this gene/protein do?
Show (35)

Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 01 September 2019 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Neoplasm Proteins
  • Esophageal Cancer
  • Brain Tumours
  • Pancreatic Cancer
  • Sensitivity and Specificity
  • Transcription
  • Transfection
  • Lung Cancer
  • Chromosome 5
  • Promoter Regions
  • Translational Medical Research
  • Untranslated Regions
  • Cell Movement
  • SPARC
  • Down-Regulation
  • Skin Cancer
  • Recombinant Proteins
  • Melanoma
  • Protein Biosynthesis
  • Smoke
  • Sri Lanka
  • Vestibular Nerve
  • Neoplasm Metastasis
  • Cancer Gene Expression Regulation
  • Neoplasm Invasiveness
  • Survival Rate
  • Osteosarcoma
  • DNA Methylation
  • Taiwan
  • Risk Factors
  • Thyroid Cancer
  • Breast Cancer
  • Osteonectin
  • Statistics as Topic
  • Oligonucleotide Array Sequence Analysis
  • Biomarkers, Tumor
  • Disease Progression
  • Polymerase Chain Reaction
  • Repressor Proteins
  • U937 Cells
  • Cell Proliferation
  • Messenger RNA
  • Gene Expression Profiling
  • Immunohistochemistry
Tag cloud generated 01 September, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (9)

Latest Publications: SPARC (cancer-related)

Luo HL, Chiang PH, Huang CC, et al.
Methylation of SPARCL1 Is Associated with Oncologic Outcome of Advanced Upper Urinary Tract Urothelial Carcinoma.
Int J Mol Sci. 2019; 20(7) [PubMed] Free Access to Full Article Related Publications
Advanced upper urinary tract urothelial carcinoma (UTUC) is often associated with poor oncologic outcomes. The secreted protein acidic and rich in cysteine-like 1 (SPARCL1) protein, belongs to the SPARC-related family of matricellular proteins. Much literature has been published describing the role of SPARCL1 in the prognosis many cancers. In this study, methylated promoter regions in high-grade and high-stage upper urinary urothelial tumours compared with normal urothelium were analyzed and revealed that

Hao S, Lv J, Yang Q, et al.
Identification of Key Genes and Circular RNAs in Human Gastric Cancer.
Med Sci Monit. 2019; 25:2488-2504 [PubMed] Free Access to Full Article Related Publications
BACKGROUND Globally, gastric cancer (GC) is the third most common source of cancer-associated mortality. The aim of this study was to identify key genes and circular RNAs (circRNAs) in GC diagnosis, prognosis, and therapy and to further explore the potential molecular mechanisms of GC. MATERIAL AND METHODS Differentially expressed genes (DEGs) and circRNAs (DE circRNAs) between GC tissues and adjacent non-tumor tissues were identified from 3 mRNA and 3 circRNA expression profiles. Functional analyses were performed, and protein-protein interaction (PPI) networks were constructed. The significant modules and key genes in the PPI networks were identified. Kaplan-Meier analysis was performed to evaluate the prognostic value of these key genes. Potential miRNA-binding sites of the DE circRNAs and target genes of these miRNAs were predicted and used to construct DE circRNA-miRNA-mRNA networks. RESULTS A total of 196 upregulated and 311 downregulated genes were identified in GC. The results of functional analysis showed that these DEGs were significantly enriched in a variety of functions and pathways, including extracellular matrix-related pathways. Ten hub genes (COL1A1, COL3A1, COL1A2, COL5A2, FN1, THBS1, COL5A1, SPARC, COL18A1, and COL11A1) were identified via PPI network analysis. Kaplan-Meier analysis revealed that 7 of these were associated with a poor overall survival in GC patients. Furthermore, we identified 2 DE circRNAs, hsa_circ_0000332 and hsa_circ_0021087. To reveal the potential molecular mechanisms of circRNAs in GC, DE circRNA-microRNA-mRNA networks were constructed. CONCLUSIONS Key candidate genes and circRNAs were identified, and novel PPI and circRNA-microRNA-mRNA networks in GC were constructed. These may provide useful information for the exploration of potential biomarkers and targets for the diagnosis, prognosis, and therapy of GC.

Feng Z, Song Y, Qian J, et al.
Differential expression of a set of microRNA genes reveals the potential mechanism of papillary thyroid carcinoma.
Ann Endocrinol (Paris). 2019; 80(2):77-83 [PubMed] Related Publications
BACKGROUND: Our aim was to explore the potential mechanism underlying papillary thyroid carcinoma (PTC) development.
METHODS: Gene expression profile data GSE3467 and microRNA (miRNA) expression profile data E-TABM-68 were downloaded from Gene Expression Omnibus and Array Express database respectively. The differentially expressed genes (DEGs) and miRNAs between PTC patients and normal individuals were screened. Then, the significant target DEGs regulated by differentially expressed miRNAs were mapped to protein-protein interaction (PPI) network and functional modules were screened. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis for miRNA genes were performed using DAVID (the Database for Annotation, Visualization and Integration Discovery) tool.
RESULTS: Total 4307 DEGs and 23 differentially expressed miRNAs were identified. A PPI subnetwork containing 612 nodes and 713 edges was constructed. Total 5 DEGs such as SPARC (secreted protein acidic and rich in cysteine), FN1 (fibronectin 1), THBS1 (thrombospondin 1), COL1A1 (collagen, type I, alpha 1) and COL7A1 (collagen, type VII, alpha 1) were found in module M1. The up-regulated DEGs were significantly related with cell adhesion molecules (CAMs), response to wounding and immune response. The down-regulated DEGs were significantly enriched in metabolism related pathways and transcription related with GO terms.
CONCLUSIONS: ECM-receptor interaction and amino acid degradation may play key roles in the mechanism of PTC progression.

Zhao Y, Cao J, Melamed A, et al.
Losartan treatment enhances chemotherapy efficacy and reduces ascites in ovarian cancer models by normalizing the tumor stroma.
Proc Natl Acad Sci U S A. 2019; 116(6):2210-2219 [PubMed] Free Access to Full Article Related Publications
In ovarian cancer patients, tumor fibrosis and angiotensin-driven fibrogenic signaling have been shown to inversely correlate with survival. We sought to enhance drug delivery and therapeutic efficacy by remodeling the dense extracellular matrix in two orthotopic human ovarian carcinoma xenograft models. We hypothesized that targeting the angiotensin signaling axis with losartan, an approved angiotensin system inhibitor, could reduce extracellular matrix content and the associated "solid stress," leading to better anticancer therapeutic effect. We report here four translatable findings: (

Lu H, Ju DD, Yang GD, et al.
Targeting cancer stem cell signature gene SMOC-2 Overcomes chemoresistance and inhibits cell proliferation of endometrial carcinoma.
EBioMedicine. 2019; 40:276-289 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Endometrial cancer is one of the most common gynecological malignancies and has exhibited an increasing incidence rate in recent years. Cancer stem cells (CSCs), which are responsible for tumor growth and chemoresistance, have been confirmed in endometrial cancer. However, it is still challenging to identify endometrial cancer stem cells to then target for therapy.
METHODS: Flow cytometry was used to identify the endometrial cancer stem cells. Sphere formation assay, western blotting, qRT-PCR assay, cell viability assay, xenograft assay and immunohistochemistry staining analysis were utilized to evaluate the effect of SPARC-related modular calcium binding 2 (SMOC-2) on the cells proliferation and drug resistance. Cell viability assay, qRT-PCR assay, immunofluorescence staining, Co-IP assay and luciferase reporter gene assay were performed to explore the possible molecular mechanism by which SMOC-2 activates WNT/β-catenin pathway.
FINDINGS: We found the expression of SPARC-related modular calcium binding 2 (SMOC-2), a member of SPARC family, was higher in endometrial CSCs than that in non-CSCs. SMOC-2 was also more highly expressed in spheres than in monolayer cultures. The silencing of SMOC-2 suppressed cell sphere ability; reduced the expression of the stemness-associated genes SOX2, OCT4 and NANOG; and enhanced chemosensitivity in endometrial cancer cells. By co-culture IP assay, we demonstrated that SMOC-2 directly interacted with WNT receptors (Fzd6 and LRP6), enhanced ligand-receptor interaction with canonical WNT ligands (Wnt3a and Wnt10b), and finally, activated the WNT/β-catenin pathway in endometrial cancer. SMOC-2 expression was closely correlated with CSC markers CD133 and CD44 expression in endometrial cancer tissue.
INTERPRETATION: Taken together, we conclude that SMOC-2 might be a novel endometrial cancer stem cell signature gene and therapeutic target for endometrial cancer. FUND: National Natural Science Foundation of China, Scientific and Technological Innovation Act Program of Shanghai Science and Technology Commission, Scientific and Technological Innovation Act Program of Fengxian Science and Technology Commission, Natural Science Foundation of Shanghai.

Suzuki H, Yamamoto E, Yamano HO, et al.
Integrated Analysis of the Endoscopic, Pathological and Molecular Characteristics of Colorectal Tumorigenesis.
Digestion. 2019; 99(1):33-38 [PubMed] Related Publications
BACKGROUND: Colorectal cancers (CRCs) develop through the accumulation of genetic and epigenetic alterations of oncogenes and tumor suppressor genes. In addition to the well-characterized adenoma-carcinoma sequence, the serrated neoplasia pathway is now recognized as an alternative pathway for CRC development.
SUMMARY: Through analysis of the colonoscopic, pathological, and molecular features of colorectal tumors, we identified a novel microsurface structure characteristic of serrated lesions. The Type II-Open (Type II-O) pit pattern is highly specific to sessile serrated adenoma/polyps (SSA/Ps), and Type-II-O-positive tumors frequently exhibit v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutation and 5'-C-phosphate-G-3' (CpG) island hypermethylation. By screening DNA methylation associated with the development of serrated lesions, we detected methylation of secreted protein acidic and rich in cysteine (SPARC)-related modular calcium binding 1 (SMOC1) in traditional serrated adenomas (TSAs). Epigenetic silencing of SMOC1 is prevalent among TSAs but it is rarely observed in SSA/Ps, which suggests SMOC1 could be a useful diagnostic marker of serrated lesions. We also searched for epigenetic alterations associated with the growth pattern of colorectal tumors and found that methylation of neurotensin receptor 1 is associated with lateral and non-invasive tumor growth. Key Message: Through the summarized studies, we have been able to identify novel morphological and molecular features that could contribute to a better understanding of colorectal tumors and to improved clinical diagnosis.

Šekoranja D, Boštjančič E, Salapura V, et al.
Primary aneurysmal bone cyst with a novel SPARC-USP6 translocation identified by next-generation sequencing.
Cancer Genet. 2018; 228-229:12-16 [PubMed] Related Publications
Aneurysmal bone cyst (ABC) is a benign but locally aggressive, mostly pediatric neoplasm, with characteristic USP6 gene rearrangement that distinguishes it from a secondary ABC and other primary bone tumors. With the advent of next-generation sequencing (NGS) technology, several hitherto unknown USP6 fusion partners have been identified in ABC. Accordingly, we present a case of an 18-year-old male with a solid sub-periosteal primary ABC in the diaphysis of the left femur. Using an NGS-based assay, we identified SPARC-USP6 fusion, which has not previously been described in ABC. Including our case, the list of currently known USP6 fusion partners in primary ABC include: CDH11, CNBP, COL1A1, CTNNB1, EIF1, FOSL2, OMD, PAFAH1B1, RUNX2, SEC31A, SPARC, STAT3 and THRAP3.

Hsiao WC, Sung SY, Chung LWK, Hsieh CL
Osteonectin Promoter-Mediated Suicide Gene Therapy of Prostate Cancer.
Methods Mol Biol. 2019; 1895:27-42 [PubMed] Related Publications
Suicide gene therapy using the herpes simplex virus thymidine kinase (HSV-tk) gene, combined with the prodrug ganciclovir (GCV) medication, is a promising approach for the treatment of malignant tumors, including prostate cancer. The success of this therapeutic strategy requires tissue- or tumor-specific gene expression and efficient gene delivery. In this chapter, we describe the experimental protocols of key methodologies, including promoter construction, reporter assay, adenoviral vector construction and preparation, HSV-tk enzymatic assay and cytotoxicity assay to evaluate the specificity and efficacy of osteonectin promoter-mediated HSV-tk/GCV suicide gene therapy of prostate cancer.

Sun W, Feng J, Yi Q, et al.
SPARC acts as a mediator of TGF-β1 in promoting epithelial-to-mesenchymal transition in A549 and H1299 lung cancer cells.
Biofactors. 2018; 44(5):453-464 [PubMed] Related Publications
Migration and metastasis of tumor cells greatly contributes to the failure of cancer treatment. Recently, the extracellular protein secreted protein acidic and rich in cysteine (SPARC) has been reported closely related to tumorigenesis. Some articles have suggested that SPARC promoted metastasis in several highly metastatic tumors. However, there are also some studies shown that SPARC acted as an antitumor factor. SPARC-induced epithelial-to-mesenchymal transition (EMT) in melanoma cells and promoted EMT in hepatocellular carcinoma. Therefore, the role of SPARC in tumorigenesis and its relationship with EMT is still unclear. In this study, we investigated the expression change of SPARC in A549 and H1299 lung cancer cells undergoing EMT process. Our study indicated that SPARC was upregulated in A549 and H1299 cells EMT process. We further investigated the function of SPARC on proliferation, migration, and EMT process of A549 and H1299 cells. Overexpression of SPARC promoted the migration and EMT of A549 and H1299 cells. Knockdown SPARC inhibited the EMT of A549 cells. Overexpression of SPARC induced the increased expression of p-Akt and P-ERK. Furthermore, exogenous SPARC peptide promoted transforming growth factor (TGF)-β1-induced EMT of A549 and H1299 cells. SPARC knockdown partially eliminated TGF-β1 function in inducing EMT of A549 cells. SPARC follistatin-like functional domain reduced the expression of E-cadherin, but had no effect on the expression of p-Akt and p-ERK. In conclusion, we elucidated that SPARC contributes to tumorigenesis by promoting migration and EMT of A549 and H1299 lung cancer cells. These results will provide some new suggestion for lung cancer treatment. © 2018 BioFactors, 44(5):453-464, 2018.

Bawazeer S, Sabry D, Mahmoud RH, et al.
Association of SPARC gene polymorphisms rs3210714 and rs7719521 with VEGF expression and utility of Nottingham Prognostic Index scoring in breast cancer in a sample of Egyptian women.
Mol Biol Rep. 2018; 45(6):2313-2324 [PubMed] Related Publications
Breast cancer is the most common malignancy in women. To our knowledge, there is no single study conducted on the role of secreted protein acidic and rich in cysteine (SPARC) gene polymorphism in breast cancer risk or prognosis. The present study aims to investigate the probable role of SPARC genetic polymorphisms in development of breast cancer; their correlation with immunohistochemical expression of VEGF; and their association with breast cancer prognosis in the Egyptian population. The study sample included 238 Egyptian females who were divided into two groups: breast cancer group (118 patients) and healthy control group (120 subjects). SPARC gene single nucleotide polymorphisms rs3210714 and rs7719521 were genotyped. Allelic and genotypic frequencies were determined in both groups and association with ductal breast carcinoma, clinicopathological and prognostic characters were determined. For SPARC rs3210714, a significant difference was observed in the codominant model and both A and G alleles' frequencies between breast cancer patients and control group (P < 0.001). For rs7719521, a significant difference in codominant and dominant models as well as in both A and C alleles' frequencies between breast cancer and control groups (P < 0.001) was observed. A significant relation was found between SPARC rs3210714 and rs7719521, and immunohistochemical expression of VEGF (P = 0.046 and P = 0.027, respectively). SPARC rs7719521 showed a significant association with Nottingham Prognostic Index (NPI) (P = 0.032). The present study revealed that SPARC rs3210714 and rs7719521 polymorphisms are associated with breast cancer risk and its prognosis. Therefore, these SNPs may be useful in predicting the increased risk of breast cancer.

Andriani F, Landoni E, Mensah M, et al.
Diagnostic role of circulating extracellular matrix-related proteins in non-small cell lung cancer.
BMC Cancer. 2018; 18(1):899 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Interactions between cancer cells and the surrounding microenvironment are crucial determinants of cancer progression. During this process, bi-directional communication among tumor cells and cancer associated fibroblasts (CAF) regulate extracellular matrix (ECM) deposition and remodeling. As a result of this dynamic process, soluble ECM proteins can be released into the bloodstream and may represent novel circulating biomarkers useful for cancer diagnosis. The aim of the present study was to measure the levels of three circulating ECM related proteins (COL11A1, COL10A1 and SPARC) in plasma samples of lung cancer patients and in healthy heavy-smokers controls and test whether such measurements have diagnostic or prognostic value.
METHODS: Gene expression profiling of lung fibroblasts isolated from paired normal and cancer tissue of NSCLC patients was performed by gene expression microarrays. The prioritization of the candidates for the study of circulating proteins in plasma was based on the most differentially expressed genes in cancer associated fibroblasts. Soluble ECM proteins were assessed by western blot in the conditioned medium of lung fibroblasts and by ELISA assays in plasma samples.
RESULTS: Plasma samples from lung cancer patients and healthy heavy-smokers controls were tested for levels of COL11A1 and COL10A1 (n = 57 each) and SPARC (n = 90 each). Higher plasma levels of COL10A1 were detected in patients (p ≤ 0.001), a difference that was driven specifically by females (p < 0.001). No difference in COL11A1 levels between patients and controls was found. SPARC levels were also higher in plasma patients than controls (p < 0.001) with good performance in discriminating the two groups (AUC = 0.744). No significant association was observed between plasma proteins levels and clinicopathological features or survival.
CONCLUSION: Soluble factors related to proficient tumor-stroma cross-talk are detectable in plasma of primary lung cancer patients and may represent a valuable complementary diagnostic tool to discriminate lung cancer patients from healthy heavy-smokers individuals as shown for the SPARC protein.

Moses-Fynn E, Tang W, Beyene D, et al.
Correlating blood-based DNA methylation markers and prostate cancer risk in African-American men.
PLoS One. 2018; 13(9):e0203322 [PubMed] Free Access to Full Article Related Publications
The objective of this work was to investigate the clinical significance of promoter gene DNA methylation changes in whole blood from African-American (AA) men with prostate cancer (PCa). We used high throughput pyrosequencing analysis to quantify percentage DNA methylation levels in a panel of 8 genes (RARβ2, TIMP3, SPARC, CDH13, HIN1, LINE1, CYB5R2 and DRD2) in blood DNA obtained from PCa and non-cancerous controls cases. Correlations of methylation status and various clinicopathological features were evaluated. Six genes tested achieved significant difference in DNA methylation levels between the PCa compared to control cases (P < 0.05). The TIMP3 loci demonstrated significant correlation of DNA methylation with age for all cases analyzed (p < 0.05). We observed an inverse correlation between CDH13 methylation (p = 0.045; r = -0.21) and serum vitamin D level whereas TIMP3 methylation (p = 0.021; r = -0.24) and DRD2 methylation (p = 0.056; r = -0.201) showed inverse correlation with supplementary vitamin D in the cancer cases. We also observed a direct correlation between methylation of RARβ2 (p = 0.0036; r = 0.293) and SPARC (p = 0.0134; r = 0.20) loci with PSA level in the controls but not the cancer cases. In addition, alcohol cases significantly correlated with higher RARβ2 methylation (p = 0.0314) in comparison with non-alcohol cases. Furthermore, we observed an inverse correlation of DRD2 methylation (p = 0.0349; r = -0.343) and Gleason score. Our data suggests that promoter methylation occurred more frequently in the blood of AA PCa and is associated with various clinicopathological features in AA men with PCa.

Hauptman N, Boštjančič E, Žlajpah M, et al.
Bioinformatics Analysis Reveals Most Prominent Gene Candidates to Distinguish Colorectal Adenoma from Adenocarcinoma.
Biomed Res Int. 2018; 2018:9416515 [PubMed] Free Access to Full Article Related Publications
Colorectal cancer (CRC) is one of the leading causes of death by cancer worldwide. Bowel cancer screening programs enable us to detect early lesions and improve the prognosis of patients with CRC. However, they also generate a significant number of problematic polyps, e.g., adenomas with epithelial misplacement (pseudoinvasion) which can mimic early adenocarcinoma. Therefore, biomarkers that would enable us to distinguish between adenoma with epithelial misplacement (pseudoinvasion) and adenoma with early adenocarcinomas (true invasion) are needed. We hypothesized that the former are genetically similar to adenoma and the latter to adenocarcinoma and we used bioinformatics approach to search for candidate genes that might be potentially used to distinguish between the two lesions. We used publicly available data from Gene Expression Omnibus database and we analyzed gene expression profiles of 252 samples of normal mucosa, colorectal adenoma, and carcinoma. In total, we analyzed 122 colorectal adenomas, 59 colorectal carcinomas, and 62 normal mucosa samples. We have identified 16 genes with differential expression in carcinoma compared to adenoma:

Gill MK, Christova T, Zhang YY, et al.
A feed forward loop enforces YAP/TAZ signaling during tumorigenesis.
Nat Commun. 2018; 9(1):3510 [PubMed] Free Access to Full Article Related Publications
In most solid tumors, the Hippo pathway is inactivated through poorly understood mechanisms that result in the activation of the transcriptional regulators, YAP and TAZ. Here, we identify NUAK2 as a YAP/TAZ activator that directly inhibits LATS-mediated phosphorylation of YAP/TAZ and show that NUAK2 induction by YAP/TAZ and AP-1 is required for robust YAP/TAZ signaling. Pharmacological inhibition or loss of NUAK2 reduces the growth of cultured cancer cells and mammary tumors in mice. Moreover, in human patient samples, we show that NUAK2 expression is elevated in aggressive, high-grade bladder cancer and strongly correlates with a YAP/TAZ gene signature. These findings identify a positive feed forward loop in the Hippo pathway that establishes a key role for NUAK2 in enforcing the tumor-promoting activities of YAP/TAZ. Our results thus introduce a new opportunity for cancer therapeutics by delineating NUAK2 as a potential target for re-engaging the Hippo pathway.

Qadir F, Aziz MA, Sari CP, et al.
Transcriptome reprogramming by cancer exosomes: identification of novel molecular targets in matrix and immune modulation.
Mol Cancer. 2018; 17(1):97 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Exosomes are extracellular vesicles released by almost all cell types, including cancer cells, into bodily fluids such as saliva, plasma, breast milk, semen, urine, cerebrospinal fluid, amniotic fluid, synovial fluid and sputum. Their key function being intercellular communication with both neighbouring as well as distant cells. Cancer exosomes have been shown to regulate organ-specific metastasis. However, little is known about the functional differences and molecular consequences of normal cells responding to exosomes derived from normal cells compared to those derived from cancer cells.
METHODS: Here, we characterised and compared the transcriptome profiles of primary human normal oral keratinocytes (HNOK) in response to exosomes isolated from either primary HNOK or head and neck squamous cell carcinoma (HNSCC) cell lines.
RESULTS: In recipient HNOK cells, we found that regardless of normal or cancer derived, exosomes altered molecular programmes involved in matrix modulation (MMP9), cytoskeletal remodelling (TUBB6, FEZ1, CCT6A), viral/dsRNA-induced interferon (OAS1, IFI6), anti-inflammatory (TSC22D3), deubiquitin (OTUD1), lipid metabolism and membrane trafficking (BBOX1, LRP11, RAB6A). Interestingly, cancer exosomes, but not normal exosomes, modulated expression of matrix remodelling (EFEMP1, DDK3, SPARC), cell cycle (EEF2K), membrane remodelling (LAMP2, SRPX), differentiation (SPRR2E), apoptosis (CTSC), transcription/translation (KLF6, PUS7). We have also identified CEP55 as a potential cancer exosomal marker.
CONCLUSIONS: In conclusion, both normal and cancer exosomes modulated unique gene expression pathways in normal recipient cells. Cancer cells may exploit exosomes to confer transcriptome reprogramming that leads to cancer-associated pathologies such as angiogenesis, immune evasion/modulation, cell fate alteration and metastasis. Molecular pathways and biomarkers identified in this study may be clinically exploitable for developing novel liquid-biopsy based diagnostics and immunotherapies.

Lewin J, Soltan Ghoraie L, Bedard PL, et al.
Gene expression signatures prognostic for relapse in stage I testicular germ cell tumours.
BJU Int. 2018; 122(5):814-822 [PubMed] Related Publications
OBJECTIVES: To identify differentially expressed genes between relapsed and non-relapsed clinical stage I testicular germ cell tumours (TGCTs).
MATERIALS AND METHODS: We reviewed patients with clinical stage I non-seminoma and seminoma from an institutional database (2000-2012) who were managed by active surveillance. Patients with non-relapsed non-seminoma and non-relapsed seminoma were defined as being relapse-free after 2 and 3 years of surveillance, respectively. RNA extraction and gene expression analysis was performed on archival primary tumour samples and gene-set enrichment analysis (GSEA) was conducted in order to identify differentiating biological pathways.
RESULTS: A total of 57 patients (relapsed non-seminoma, n = 12; relapsed seminoma, n =15; non-relapsed non-seminoma, n = 15; non-relapsed seminoma, n = 15) were identified, with a median (range) relapse time of 5.6 (2.5-18.1) and 19.3 (4.7-65.3) months in the relapsed non-seminoma and relapsed seminoma cohorts, respectively. A total of 1 039 differentially expressed genes were identified that separated relapsed and non-relapsed groups. In patients with relapse, GSEA revealed enrichment in pathways associated with differentiation, such as skeletal development (i.e. FGFR1, BMP4, GLI2, SPARC, COL2A1), tissue (i.e. BMP4, SPARC, COL13A1) and bone remodelling (i.e. CARTPT, GLI2, MGP). A discriminative gene expression profile between relapsed and non-relapsed cases was discovered when combining non-seminoma and seminoma samples using 10- and 30-probe signatures; however, this profile was not observed in the seminoma and non-seminoma cohorts individually.
CONCLUSION: A discriminating signature for relapsed disease was identified for clinical stage I TGCT that we were not able to identify by histology alone. Further validation is required to determine if this signature provides independent prognostic information to standard pathological risk factors.

Dame MK, Attili D, McClintock SD, et al.
Identification, isolation and characterization of human LGR5-positive colon adenoma cells.
Development. 2018; 145(6) [PubMed] Free Access to Full Article Related Publications
The intestine is maintained by stem cells located at the base of crypts and distinguished by the expression of LGR5. Genetically engineered mouse models have provided a wealth of information about intestinal stem cells, whereas less is known about human intestinal stem cells owing to difficulty detecting and isolating these cells. We established an organoid repository from patient-derived adenomas, adenocarcinomas and normal colon, which we analyzed for variants in 71 colorectal cancer (CRC)-associated genes. Normal and neoplastic colon tissue organoids were analyzed by immunohistochemistry and fluorescent-activated cell sorting for LGR5. LGR5-positive cells were isolated from four adenoma organoid lines and were subjected to RNA sequencing. We found that LGR5 expression in the epithelium and stroma was associated with tumor stage, and by integrating functional experiments with LGR5-sorted cell RNA sequencing data from adenoma and normal organoids, we found correlations between LGR5 and CRC-specific genes, including dickkopf WNT signaling pathway inhibitor 4 (

Torrebadell M, Díaz-Beyá M, Kalko SG, et al.
A 4-gene expression prognostic signature might guide post-remission therapy in patients with intermediate-risk cytogenetic acute myeloid leukemia.
Leuk Lymphoma. 2018; 59(10):2394-2404 [PubMed] Related Publications
In intermediate-risk cytogenetic acute myeloid leukemia (IRC-AML) patients, novel biomarkers to guide post-remission therapy are needed. We analyzed with high-density arrays 40 IRC-AML patients who received a non-allogeneic hematopoietic stem-cell transplantation-based post-remission therapy, and identified a signature that correlated with early relapse. Subsequently, we analyzed selected 187 genes in 49 additional IRC-AML patients by RT-PCR. BAALC, MN1, SPARC and HOPX overexpression correlated to refractoriness. BAALC or ALDH2 overexpression correlated to shorter overall survival (OS) (5-year OS: 33 ± 8.6% vs. 73.7 ± 10.1%, p = .006; 32 ± 9.3% vs. 66.4 ± 9.7%, p = .016), whereas GPR44 or TP53INP1 overexpression correlated to longer survival (5-year OS: 66.7 ± 10.3% vs. 35.4 ± 9.1%, p = .04; 58.3 ± 8.2% vs. 23.1 ± 11.7%, p = .029). A risk-score combining these four genes expression distinguished low-risk and high-risk patients (5-year OS: 79 ± 9% vs. 30 ± 8%, respectively; p = .001) in our cohort and in an independent set of patients from a public repository. Our 4-gene signature may add prognostic information and guide post-remission treatment in IRC-AML patients.

Shintakuya R, Kondo N, Murakami Y, et al.
The high stromal SPARC expression is independently associated with poor survival of patients with resected pancreatic ductal adenocarcinoma treated with adjuvant gemcitabine in combination with S-1 or adjuvant gemcitabine alone.
Pancreatology. 2018; 18(2):191-197 [PubMed] Related Publications
BACKGROUND: Although postoperative adjuvant chemotherapy for pancreatic ductal adenocarcinoma (PDAC) improves survival, its efficacy varies among individuals. Identification of biomarkers that can predict the efficacy of adjuvant chemotherapy for PDAC is essential.
OBJECTIVES: To investigate the predictive value of secreted protein acidic and rich in cysteine (SPARC) expression in patients with PDAC treated with adjuvant gemcitabine in combination with S-1 (adjuvant GS) or adjuvant gemcitabine alone (adjuvant G alone).
METHODS: Stromal SPARC and cytoplasmic SPARC were examined immunohistochemically in 211 PDAC patients treated with adjuvant GS or G alone after resection. The association of SPARC expression with clinicopathological factors, disease-free survival (DFS) and overall survival (OS) were analyzed.
RESULTS: In multivariate analysis, borderline resectable with arterial contact (BR-A) (P = .002), higher preoperative CA 19-9 level (≥91 U/ml) (P = .005), moderately or poorly (P = .003), presence of lymph node metastasis (P = .012) and high stromal SPARC expression (P = .013) were independent predictors of poor DFS. Moreover, BR-A (P = .003), higher preoperative CA 19-9 level (≥91 U/ml) (P = .007) and high stromal SPARC expression (P < .001) were identified as independent predictors of poor OS. In contrast, cytoplasmic SPARC expression did not affect DFS and OS.
CONCLUSIONS: High stromal SPARC expression was an independent predictor of poor DFS and OS in patients treated with adjuvant GS or G alone. Stromal SPARC expression could be a relevant biomarker for prediction of prognosis in PDAC patients after resection treated with adjuvant GS or G alone.

Yan J, Zhang J, Zhang X, et al.
SPARC is down-regulated by DNA methylation and functions as a tumor suppressor in T-cell lymphoma.
Exp Cell Res. 2018; 364(2):125-132 [PubMed] Related Publications
The aim of this study was to assess the functional role of SPARC in T-cell non-Hodgkin's lymphoma (T-NHL), as well as the underlying molecular mechanisms. Here, we first identified SPARC expression in T-NHL tissues and cell lines through western blot and real-time PCR (RT-PCR). Overall survival of T-NHL patients with different levels of SPARC was assessed by Kaplan-Meier survival curves. Then cell proliferation, apoptosis, migration and invasion of T-NHL cells with either knockdown or overexpression of SPARC were determined by MTT, flow cytometry, transwell migration and invasion assay, respectively. Finally, the molecular mechanism by which SPARC modulated T-NHL cell progression was assessed. We confirmed that SPARC was significantly down-regulated in T-NHL tissues and cell lines. T-NHL patients with high levels of SPARC demonstrated a favorable clinical outcome. SPARC significantly suppressed cell proliferation, migration and invasion, and EMT process, but facilitated cell apoptosis in T-NHL cells. Further, we found that loss of SPARC expression in T-NHL tissues and cell lines, both in mRNA and protein levels, was associated with the aberrant DNA methylation in SPRAC gene, and the disrupted SPARC expression could be rescued after treatment with the demethylating agent 5-Aza-2'-deoxycitydine (5-Aza-Cdr). Additionally, 5-Aza-Cdr reversed SPARC hypermethylation to restore its biological role as a tumor suppressor in T-NHL cells, including inhibiting cell proliferation, invasion and migration, while promoting cell apoptosis. Our data provided evidence that DNA methylation in SPARC gene may play a role in the progression of T-NHL.

Koshizuka K, Hanazawa T, Kikkawa N, et al.
Antitumor miR-150-5p and miR-150-3p inhibit cancer cell aggressiveness by targeting SPOCK1 in head and neck squamous cell carcinoma.
Auris Nasus Larynx. 2018; 45(4):854-865 [PubMed] Related Publications
OBJECTIVE: Our recent studies have revealed that both strands of pre-miRNAs, the guide strand and the passenger strand, are involved in cancer pathogenesis. Analyses of miRNA expression signatures by RNA sequencing in head and neck squamous cell carcinoma (HNSCC) showed that both of the strands of pre-miR-150 (miR-150-5p and miR-150-3p) were significantly downregulated, and that these miRNAs acted as antitumor miRNAs in HNSCC cells. The aim of this study was to identify oncogenic genes in HNSCC cells that were regulated by miR-150-5p and miR-150-3p.
METHODS: Genome-wide gene expression studies, in silico analyses and dual-luciferase reporter assays were carried out to predict miR-150-5p and miR-150-3p regulation in HNSCC cells. Knockdown assay was applied to investigate the functional significance of the target gene. Overall patient survival as a function of target gene expression was estimated by The Cancer Genome Atlas (TCGA) database.
RESULTS: A total of 19 genes were putative targets of both miR-150-5p and miR-150-3p regulation. Among them, SPOCK1 (SPARC/osteonectin, cwcv and kazal-like domains proteoglycan 1) was directly regulated by both miRNAs in HNSCC cells. Knockdown studies using si-SPOCK1 showed that expression of SPOCK1 enhanced HNSCC cell aggressiveness. Overexpression of SPOCK1/SPOCK1 was confirmed in HNSCC clinical specimens. Interestingly, analysis of a large number of patients in the TCGA database (n=248) demonstrated that patients with high SPOCK1 expression had significantly shorter survival than did those with low SPOCK1 expression (P=0.0003). Moreover, 15 pathways were identified as SPOCK1-mediated downstream pathways.
CONCLUSION: Downregulation of both strands of pre-miR-150 (miR-150-5p and miR-150-3p) and overexpression of SPOCK1 contribute to the aggressive nature of HNSCC. The involvement of passenger strand miRNA in the regulation of HNSCC pathogenesis is a novel concept in RNA research.

Liu T, Qiu X, Zhao X, et al.
Hypermethylation of the SPARC promoter and its prognostic value for prostate cancer.
Oncol Rep. 2018; 39(2):659-666 [PubMed] Related Publications
Secreted protein acidic and rich in cysteine (SPARC) is a secreted matricellular glycoprotein and plays a key role in the development of many tissues and organ types. However, the role of SPARC in prostate cancer (PCa) is still controversial. The aim of the present study was to investigate the abnormalities in the expression of SPARC and its promoter hypermethylation in prostate cancers and in correlated clinicopathological profiles. We examined the hypermethylation of the SPARC promoter as a potential mechanism for suppressing SPARC in PCa. The clinicopathological correlation between SPARC and its promoter expression and the prognostic significance of the aberrantly expressed genes were evaluated to identify novel biomarkers of PCa. SPARC expression was decreased in PCa cell lines, which correlated with hypermethylation of the SPARC promoter. Treatment with the demethylating agent 5-Aza-Cdr restored SPARC expression. Seventy percent (145 of 207) of the primary tumors exhibited SPARC hypermethylation, while only 2.6% was found in normal prostate mucosa (n=38). In PCa cases, SPARC hypermethylation was correlated with a poorer prognosis (P=0.005; relative risk 2.659, 95% CI, 1.433‑4.562). Our findings revealed potential diagnostic markers of PCa based on specific hypermethylated CpG sites and also provided new insights of SPARC as a novel biomarker and/or treatment modality for prostate cancer.

Yamada Y, Nishikawa R, Kato M, et al.
Regulation of HMGB3 by antitumor miR-205-5p inhibits cancer cell aggressiveness and is involved in prostate cancer pathogenesis.
J Hum Genet. 2018; 63(2):195-205 [PubMed] Related Publications
Our recent determination of a microRNA (miRNA) expression signature in prostate cancer (PCa) revealed that miR-205-5p was significantly reduced in PCa tissues and that it acted as an antitumor miRNA. The aim of this study was to identify oncogenic genes and pathways in PCa cells that were regulated by antitumor miR-205-5p. Genome-wide gene expression analyses and in silico miRNA database searches showed that 37 genes were putative targets of miR-205-5p regulation. Among those genes, elevated expression levels of seven in particular (HMGB3, SPARC, MKI67, CENPF, CDK1, RHOU, and POLR2D) were associated with a shorter disease-free survival in a large number of patients in the The Cancer Genome Atlas (TCGA) database. We focused on high-mobility group box 3 (HMGB3) because it was the most downregulated by ectopic expression of miR-205-5p in PC3 cells and its expression was involved in PCa pathogenesis. Luciferase reporter assays showed that HMGB3 was directly regulated by miR-205-5p in PCa cells. Knockdown studies using si-HMGB3 showed that expression of HMGB3 enhanced PCa cell aggressiveness. Overexpression of HMGB3/HMGB3 was confirmed in naive PCa and castration-resistant PCa (CRPC) clinical specimens. Novel approaches to analysis of antitumor miRNA-regulated RNA networks in PCa cells may provide new insights into the pathogenic mechanisms of the disease.

Liu T, Wu C, Weng G, et al.
Bufalin Inhibits Cellular Proliferation and Cancer Stem Cell-Like Phenotypes via Upregulation of MiR-203 in Glioma.
Cell Physiol Biochem. 2017; 44(2):671-681 [PubMed] Related Publications
BACKGROUND/AIMS: Prior studies have shown that bufalin inhibits cellular proliferation and induces apoptosis in various human cancers. MicroRNA-203 (miR-203) has been shown to function as an important regulator of tumor progression at various stages. In this study, we investigated the effect of miR-203 expression and bufalin treatment on glioma cell proliferation and stem cell-like phenotypes.
METHODS: We used cell viability assay, colony formation assay, cell apoptosis assay and neurosphere formation assay to dectect the treatment effect of bufalin on U251 and U87 cells. Cells were transfected with the miR-203 mimic without bufalin treatment or cells were transfected with anti-miR-203 under bufalin treatment, the above expreiments were repeated. RT-PCR was employed to quantify miR-203 expression. Western blot was performed to detect the stem cell-like (CSC) markers, OCT4 and SOX2. Luciferase activity assay was used to determine whether the SPARC is the target of miR-203.
RESULTS: Bufalin treatment inhibited cell proliferation, colony formation, and CSC phenotypes and increased cell apoptosis and expression of miR-203. Furthermore, overexpression of miR-203 led to similar outcomes as bufalin treatment with respect to the cell viability, colony formation, cell apoptosis and the phenotypes of glioma cells. While anti-miR-203 attenuated the inhibitory effects of bufalin as promoting cell proliferation, colony formation and CSC phenotyes and inhibiting cell apoptosis. In addition, we identified SPARC as a novel target gene of miR-203.
CONCLUSIONS: These findings suggest that miR-203 plays an important role in bufalin's ability to inhibit the growth of glioma cells and the development of stem cell-like phenotypes.

Wan S, Meyer AS, Weiler SME, et al.
Cytoplasmic localization of the cell polarity factor scribble supports liver tumor formation and tumor cell invasiveness.
Hepatology. 2018; 67(5):1842-1856 [PubMed] Related Publications
The loss of epithelial cell polarity plays an important role in the development and progression of liver cancer. However, the specific molecular mechanisms supporting tumor initiation and progression are poorly understood. In this study, transcriptome data and immunofluorescence stains of tissue samples derived from hepatocellular carcinoma (HCC) patients revealed that overexpression associated with cytoplasmic localization of the basolateral cell polarity complex protein scribble (Scrib) correlated with poor prognosis of HCC patients. In comparison with HCC cells stably expressing wild-type Scrib (Scrib
CONCLUSION: Perturbation of hepatocellular polarity due to overexpression and cytoplasmic enrichment of Scrib supports tumor initiation and HCC cell dissemination through specific molecular mechanisms. Biomarker signatures identified in this study can be used for the identification of HCC patients with higher risk for the development of metastasis. (Hepatology 2018;67:1842-1856).

Zheng L, Li X, Chou J, et al.
StarD13 3'-untranslated region functions as a ceRNA for TP53INP1 in prohibiting migration and invasion of breast cancer cells by regulating miR-125b activity.
Eur J Cell Biol. 2018; 97(1):23-31 [PubMed] Related Publications
Competitive endogenous messenger RNA (ceRNA) affects transcription of other RNA molecules by competitively binding common microRNAs. Previous studies have shown that TP53INP1 functions as a suppressor in tumor metastasis. Our study elucidated StarD13 messenger RNA as a ceRNA in regulating migration and invasion of breast cancer cells. MicroRNA-125b was identified to induce metastasis of MCF-7 cells and bind with both StarD13 3'UTR and TP53INP1 3'UTR. Therefore, a ceRNA interaction between StarD13 and TP53INP1 mediated by competitively binding to miR-125b was indicated. Importantly, a microRNA-125b binding site at 4546-4560 nt on StarD13 was verified more vital for this ceRNA interaction. Indirectly regulation of SPARC in inducing metastasis of breast cancer cells by StarD13 via competitively binding with TP53INP1 was further confirmed. In conclusion, our findings demonstrate a ceRNA regulatory network which could give a better understanding of metastatic mechanisms of breast cancer.

Wang R, Li J, Zhao Y, et al.
Investigating the therapeutic potential and mechanism of curcumin in breast cancer based on RNA sequencing and bioinformatics analysis.
Breast Cancer. 2018; 25(2):206-212 [PubMed] Related Publications
BACKGROUND: Breast cancer is a prevalent cancer in female. This study aims to investigate the therapeutic potential and mechanism of curcumin in breast cancer.
METHODS: After cultivation, human breast cancer cells (MCF-7 cells) were treated with 0.1% (v/v) 15 µmol/ml curcumin-dimethylsulfoxide solution and 0.1% (v/v) dimethylsulfoxide, respectively, at 37 °C and 5% CO
RESULTS: After DEGs screening, 347 DEGs were identified. Up-regulated DEGs were enriched in 14 functions and 3 pathways, and associated with 12 drugs. Down-regulated DEGs were enriched in 14 functions and 9 pathways, and associated with 14 drugs. Moreover, 5 DEGs were associated with breast cancer, including PGAP3, MAP3K1, SERPINE1, PON2, and GSTO2. PPI network was constructed, and the top DEGs were FOS, VIM, FGF2, MAPK1, SPARC, TOMM7, PSMB10, TCEB2, SOCS1, COL4A1, UQCR11, SERPINE1, and ISG15.
CONCLUSION: Curcumin might have therapeutic potential in breast cancer through regulating breast cancer-related genes, including SERPINE1, PGAP3, MAP3K1, MAPK1, GSTO2, VIM, SPARC, and FGF2. However, validations are required.

Cai Q, Zeng S, Dai X, et al.
miR-504 promotes tumour growth and metastasis in human osteosarcoma by targeting TP53INP1.
Oncol Rep. 2017; 38(5):2993-3000 [PubMed] Related Publications
An increasing number of studies have demonstrated that microRNAs participate in the development of osteosarcoma by acting as tumour suppressor or tumour-promoting genes. We investigated the role of miR-504 in the growth and metastasis of osteosarcoma. The expression of miR-504 in clinical osteosarcoma samples was higher than that in the adjacent normal tissue and correlated with tumour size and clinical stage. Tumour protein p53-inducible nuclear protein 1 (TP53INP1) was downregulated in the clinical osteosarcoma samples compared with the adjacent normal tissues and was consistently correlated with the clinical stage. The results of dual-luciferase reporter assay and western blot analysis demonstrated that the TP53INP1 gene is a direct target of miR-504. Altogether, the Cell Counting Kit-8 (CCK-8), the colony formation, the flow cytometry and the Transwell assay results demonstrated that miR-504 promoted osteosarcoma cell growth and metastasis in vitro. P73, P21, Bax, cleaved-caspase-3 and secreted protein acidic and rich in cysteine (SPARC) were associated with the suppressive role of miR-504/TP53INP1. The overexpression of miR-504 in osteosarcoma xenografts enhanced the tumour growth and increased the metastatic burden. Collectively, these results revealed that TP53INP1 is a target gene of miR-504 and that miR-504 enhances osteosarcoma growth and promotes distant metastases by targeting TP53INP1. Thus, miR-504/TP53INP1 may be associated with osteosarcoma size and clinical stage.

Park H, Lee Y, Lee H, et al.
The prognostic significance of cancer-associated fibroblasts in pancreatic ductal adenocarcinoma.
Tumour Biol. 2017; 39(10):1010428317718403 [PubMed] Related Publications
Cancer-associated fibroblasts are abundant in the desmoplastic stroma of pancreatic ductal adenocarcinomas and are considered to play important roles in tumor progression. In this study, we investigated the expression status of secreted protein acidic and rich in cysteine, periostin, fibroblast-activated protein, and the newly developed proCOL11A1 antibody in the stroma of surgically resected pancreatic ductal adenocarcinomas and their prognostic implications. Tissue microarrays were constructed from 155 surgically resected pancreatic ductal adenocarcinomas and paired non-neoplastic pancreata and from another independent set of 48 normal/benign pancreata, and immunohistochemical stains were performed for proCOL11A1, fibroblast-activated protein, secreted protein acidic and rich in cysteine, and periostin. The immunohistochemical stain results were correlated with clinicopathological features and survival data. proCOL11A1, fibroblast-activated protein, secreted protein acidic and rich in cysteine, and periostin expression was significantly increased in the intratumoral stroma of pancreatic ductal adenocarcinomas compared to paired non-neoplastic pancreata (proCOL11A1: 145/155 (93.5%) vs 26/154 (16.9%); fibroblast-activated protein: 139/143 (97.2%) vs 82/132 (62.1%); secreted protein acidic and rich in cysteine: 113/150 (75.3%) vs 49/132 (37.1%); periostin: 135/151 (89.4%) vs 45/135 (33.3%); p < 0.001, all). While the four markers were expressed at lower levels in normal/benign pancreata, there were no significant differences in the expression frequencies among normal pancreas, acute pancreatitis, and chronic pancreatitis. Interestingly, on survival analysis, low intratumoral fibroblast-activated protein

Liang C, Shi S, Meng Q, et al.
Do anti-stroma therapies improve extrinsic resistance to increase the efficacy of gemcitabine in pancreatic cancer?
Cell Mol Life Sci. 2018; 75(6):1001-1012 [PubMed] Related Publications
Pancreatic ductal adenocarcinoma (PDAC) is among the most devastating human malignancies, with approximately 20-30% of PDAC patients receiving the surgical resection with curative intent. Although many studies have focused on finding ideal "drug chaperones" that facilitate and/or potentiate the effects of gemcitabine (GEM) in pancreatic cancer, a significant benefit in overall survival could not be demonstrated for any of these combination therapies in PDAC. Given that pancreatic cancer is characterized by desmoplasia and the dual biological roles of stroma in pancreatic cancer, we reassess the importance of stroma in GEM-based therapeutic approaches in light of current findings. This review is focused on understanding the role of stromal components in the extrinsic resistance to GEM and whether anti-stroma therapies have a positive effect on the GEM delivery. This work contributes to the development of novel and promising combination GEM-based regimens that have achieved significant survival benefits for the patients with pancreatic cancer.

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