Research IndicatorsGraph generated 01 September 2019 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex
Specific Cancers (9)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
GEO Profiles, NCBI
Search the gene expression profiles from curated DataSets in the Gene Expression Omnibus (GEO) repository.
Latest Publications: CASP2 (cancer-related)
The comprehensive screening of intracellular and extracellular microRNAs was performed to identify novel tumor suppressors. We found that miR-8073 was present in exosome and predominantly exported from colorectal cancer cells. Treatment with a synthetic miR-8073 mimic resulted in a dramatic decrease in the proliferation of various types of cancer cells, which was not observed in similarly treated normal cells. As little is known about the biological functions of miR-8073, its target mRNAs were analyzed by both mRNA expression and in silico sequence analyses, leading to five probable target candidates (FOXM1, MBD3, CCND1, KLK10, and CASP2) that enhance survival during the regulation of the cell cycle, cell proliferation, and apoptosis. We experimentally confirmed that miR-8073 binds the 3'-UTR of each of these mRNA target candidates and that the introduction of a synthetic miR-8073 mimic into cancer cells reduced levels of protein expression. Finally, the antiproliferative effects of miR-8073 were validated in vivo: the subcutaneous injection of a synthetic miR-8073 mimic suppressed colorectal tumor volume to 43% in tumor-bearing xenografted mice. These results suggest that because miR-8073 binds, and thus reduces the levels of, these oncogenic targets, cancer cells must actively downregulate miR-8073 as a survival mechanism. The introduction of miR-8073 into tumors could thus inhibit tumor growth, indicating its great potential for cancer therapeutics.
BACKGROUND: Cancer is a non-communicable disease that occurs following a mutation in the genes which control cell growth. Breast cancer is the most diagnosed cancer among South African women and a major cause of cancer-related deaths worldwide. Photodynamic therapy (PDT) is an alternative cancer therapy that uses photochemotherapeutic agents, known as photosensitizers. Drug-delivery nanoparticles are commonly used in nanomedicine to enhance drug-therapeutic efficiency. This study evaluated the photodynamic effects following treatment with 0.3 μM multiple particles delivery complex (MPDC) and irradiated with a laser fluence of 10 J/cm
METHODS: Cell damage was assessed by inverted light microscopy for cell morphology; the Apoptox-Glo triple assay was used for cell viability, caspase activity and identification of cytodamage markers; flow cytometric analysis for cell death pathways and mitochondrial membrane potential; the enzyme linked immunosorbent assay (ELISA) for cytochrome C release; and real-time reverse transcriptase polymerase chain reaction (RT-PCR) array for gene expression.
RESULTS: Laser activated-MPDC induced a significant change in morphology of PDT-treated cells, with the appearance of apoptotic like morphological features. An increase in cytotoxicity, caspase activity, cell depolarization and cytochrome C release were identified in PDT-treated cells. Finally, the upregulation of BAX, BCL-2, CASP-2 and ULK-1 genes was observed.
CONCLUSION: The MPDC yielded a successful and stable hybrid agent with potent photodynamic abilities.
Mirzaei MR, Mahmoodi M, Hassanshahi G, Ahmadi ZDown-regulation of anti-apoptotic genes in tumor cell lines is facilitated by suppression of OCT4B1.
Adv Med Sci. 2017; 62(1):97-102 [PubMed
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PURPOSE: The OCT4B1 as a variant of OCT4 is expressed in both cancer cells and tissues. The anti-apoptotic property of this variant aid cancer cells to escape from apoptosis. Therefore, the aim of the present study was to determine the effects of OCT4B1 suppression on regulation of 25 genes involved in anti-apoptotic pathway in tumor cell lines.
MATERIAL AND METHODS: AGS (gastric adenocarcinoma), 5637 (bladder tumor) and U-87MG (brain tumor) cells were transfected with specific OCT4B1 siRNA and a scramble siRNA by siRNA silencing gene technology, using Lipofectamine 2000 commercial kit. The real-time PCR technique was employed to examine and calculate fold changes of evaluated genes using the 2
RESULTS: Present results demonstrated that 22 (88%) of interested genes were similarly down-regulated in all three examined cell lines. Our results also indicated that three genes (CASP2, IGF1R,TNF) were up-regulated. The CFLAR gene was down-regulated in AGS, while it was inversely up-regulated in 5637 and U87MG cells.
CONCLUSIONS: It may possibly be concluded that suppression of OCT4B1 can lead to apoptosis in tumor cell lines and this is at least facilitated via down-regulation of examined anti-apoptotic genes. Accordingly, suppression of OCT4B1 may probably be considered as useful tool in cancer therapy and research.
Badawi A, Hehlgans S, Pfeilschifter J, et al.Silencing of the mRNA-binding protein HuR increases the sensitivity of colorectal cancer cells to ionizing radiation through upregulation of caspase-2.
Cancer Lett. 2017; 393:103-112 [PubMed
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Increased abundance of the mRNA-binding protein human antigen R (HuR) is a characteristic feature of many cancers and frequently associated with a high grade malignancy and therapy resistance. HuR elicits a broad cell survival program mainly by stabilizing or increasing the translation of mRNAs coding for anti-apoptotic effector proteins. Conversally, we previously identified the pro-apoptotic caspase-2 as a novel HuR target which is mainly regulated at the level of translation. In this study, we investigated whether siRNA-mediated HuR knockdown interferes with cell survival and radiation sensitivity by monitoring apoptosis, DNA repair and three-dimensional (3D) clonogenic survival. We observed a significant elevation in caspase-2 upon HuR depletion and in turn, a sensitization of colorectal DLD-1 and HCT-15 cells to radiation-induced apoptosis as implicated by the dose-dependent elevation of sub-G
Chromosomal instability (CIN) contributes to cancer evolution, intratumor heterogeneity, and drug resistance. CIN is driven by chromosome segregation errors and a tolerance phenotype that permits the propagation of aneuploid genomes. Through genomic analysis of colorectal cancers and cell lines, we find frequent loss of heterozygosity and mutations in BCL9L in aneuploid tumors. BCL9L deficiency promoted tolerance of chromosome missegregation events, propagation of aneuploidy, and genetic heterogeneity in xenograft models likely through modulation of Wnt signaling. We find that BCL9L dysfunction contributes to aneuploidy tolerance in both TP53-WT and mutant cells by reducing basal caspase-2 levels and preventing cleavage of MDM2 and BID. Efforts to exploit aneuploidy tolerance mechanisms and the BCL9L/caspase-2/BID axis may limit cancer diversity and evolution.
Liu J, Dou Y, Sheng MInhibition of microRNA-383 has tumor suppressive effect in human epithelial ovarian cancer through the action on caspase-2 gene.
Biomed Pharmacother. 2016; 83:1286-1294 [PubMed
] Related Publications
BACKGROUND: MicroRNAs are important cancer regulators. In this work, we examined the expression pattern and mechanistic implications of microRNA-383 (miR-383) in human epithelial ovarian cancer (EOC).
METHODS: Gene expression level of miR-383 was compared by qRT-PCR between EOC cell lines and normal ovarian epithelial cell line, and between clinical EOC tumors and adjacent non-tumor ovarian epithelial tissues. Endogenous miR-383 was downregulated through lentiviral infection. Its effects on regulating EOC proliferation, cell cycle, invasion and in vivo explant development were assessed. Possible downstream target of miR-383 in EOC, human caspase-2 gene (CASP2), was evaluated by luciferase assay and qRT-PCR. CASP2 was then genetically knocked down by siRNA to assess its functional relationship with miR-383 in regulating EOC development both in vitro and in vivo.
RESULTS: MiR-383 was overexpressed in both immortal EOC cell lines and human EOC tumors. In stably miR-383-downregulated EOC cell lines, cancer proliferation, cell cycle progression, invasion and in vivo explant development were significantly suppressed. CASP2 was confirmed to be downstream of miR-383 in EOC. SiRNA-mediated CASP2 downregulation had reverse relationship with miR-383 downregulation in regulating EOC development both in vitro and in vivo.
CONCLUSION: Inhibition of miR-383 has profound tumor suppressing effect on EOC development. And the functional regulation of miR-383 in EOC is very likely inversely associated with CASP2 gene.
Tumor suppressor p53 preserves the genomic integrity by restricting anomaly at the gene level. The hotspots for mutation in half of all colon cancers reside in p53. Hence, in a p53-mutated cellular milieu targeting cancer cells may be achievable by targeting the paralogue(s) of p53. Here we have shown the effectiveness of crocetin, a dietary component, in inducing apoptosis of colon cancer cells with varying p53 status. In wild-type p53-expressing cancer cells, p53 in one hand transactivates BAX and in parallel up-regulates p53-induced death domain protein (PIDD) that in turn cleaves and activates BID through caspase-2. Both BAX and t-BID converge at mitochondria to alter the transmembrane potential thereby leading to caspase-9 and caspase-3-mediated apoptosis. In contrast, in functional p53-impaired cells, this phytochemical exploits p53-paralogue p73, which up-regulates FAS to cleave BID through FAS-FADD-caspase-8-pathway. These findings not only underline the phenomenon of functional switch-over from p53 to p73 in p53-impaired condition, but also validate p73 as a promising and potential target for cancer therapy in absence of functional p53.
Malignant gliomas are the most common form of intrinsic primary brain tumors worldwide. Alterations in microRNAs play a role in highly invasive malignant glioma, but detail mechanism still unknown. In this study, the role and mechanism of microRNA-149 (miR-149) in glioma are investigated. We show that miR-149 is expressed at substantially higher levels in glioma than in normal tissues. Stable overexpression of miR-149 augments potent prosurvival activity, as evidenced by promotion of cell viability, inhibition of apoptosis, and induced xenografted tumor growth in vivo. We further show that Caspase-2 is identified as a functional target of miR-149 and expression of caspase-2 is inversely associated with miR-149 in vitro. In addition, miR-149 promotes tumor survival in the U87-MG and A172 cell lines and it targets caspase-2 via inactivation of the p53 and p21 pathways. There results support a special role for miR-149 by targeting Caspase-2 to impact on p53 signaling pathway. We speculate that miR-149 has distinct biological functions in p53 wild type cells and p53 mutation cells, and the mechanisms involved remain to be explored in future. Our study suggests that targeting miR-149 may be a novel therapy strategy for treating p53 wild type glioma tumors in humans.
HOTAIR (homeobox transcript antisense RNA), one of the prototypical long non-coding RNAs, has been verified overexpressed in multiple carcinomas and has emerged as a promising novel anticancer target. Its well-established role is acting as a predictor of poor prognosis and promoting cancer cell metastasis. Recently, another important mission of HOTAIR was uncovered that targeting HOTAIR caused cancer cell apoptosis. Nevertheless, so far there is no published data elaborating the mechanism. Here, we report that microRNA miR-125a-5p decreases and releases caspase 2 to promote cancer cell apoptosis after HOTAIR knockdown. We applied siRNAs targeting HOTAIR to various cancer cells, and observed apoptosis in all of these cell lines. RNA sequencing detected that miR-125a-5p was decreased after HOTAIR knockdown and miR-125a-5p mimics could rescue the apoptosis induced by HOTAIR deficiency. Luciferase assays identified caspase 2, an initiator caspase, to be a new target of miR-125a-5p. Elevated expression and subsequent cleavage of caspase 2 was observed after HOTAIR knockdown or inhibition of miR-125a-5p. RNAi of caspase 2 could attenuate the apoptosis induced by HOTAIR knockdown. In 80 clinical colon cancer tissues, HOTAIR and miR-125a-5p levels were higher than adjacent tissues, whereas caspase 2 was lower. MiR-125a-5p expression level was significantly correlated with colon tumor size, lymph node metastasis and clinical stage. These findings indicate that miR-125a-5p decreases after HOTAIR knockdown to promote cancer cell apoptosis by releasing caspase 2. Our work reveals a previously unidentified apoptotic mechanism, which might be exploitable in anticancer drug development.
Dodurga Y, Seçme M, Eroğlu C, et al.Investigation of the effects of a sulfite molecule on human neuroblastoma cells via a novel oncogene URG4/URGCP.
Life Sci. 2015; 143:27-34 [PubMed
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AIM: The aim of this study is to determine the anticancer effect of sulfite on SH-SY5Y neuroblastoma cells in vitro conditions and elucidate underlying molecular mechanism of sulfite and explore its therapeutic activity.
MAIN METHODS: In this study, cytotoxic effects of sulfite in SH-SY5Y cels were detected over time in a dose dependent manner with the IC50 doses ranging from 0.5 to 10 mM. Genotoxic effect of sulfite was shown by comet assay. IC50 doses in the SH-SY5Y cells were detected as 5 mM. Expression profiles of the target genes related to apoptosis and cell cycle control were determined by quantitative RT-PCR. Protein changes were determined by western blot analysis.
KEY FINDINGS: URG4/URGCP, CCND1, CCND2, CDK4, CDK6, E2F4 and BCL-2 gene expression levels were significantly reduced and RB1, TP53, BAX, BID, CASP2, CASP3, CASP9 and DIABLO gene expressions were significantly increased in dose group cells. The mechanism of this result may be related to sulfite dependent inhibition of cell cycle at the G1 phase by down-regulating URG4/URGCP or CCND1, CDK4, CDK6 gene expression and stimulating apoptosis via the intrinsic pathway. Sulfite suppressed invasion and colony formation in SH-SY5Y cell line using matrigel invasion chamber and colony formation assay, respectively.
SIGNIFICANCE: It is thought that sulfite demonstrates anticarcinogenesis activity by affecting cell cycle arrest, apoptosis s, invasion, and colony formation on SH-SY5Y cells. Sulfite may be an effective agent for treatment of neuroblastoma as a single agent or in combination with other agents.
Eroğlu C, Seçme M, Bağcı G, Dodurga YAssessment of the anticancer mechanism of ferulic acid via cell cycle and apoptotic pathways in human prostate cancer cell lines.
Tumour Biol. 2015; 36(12):9437-46 [PubMed
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Studies on genetic changes underlying prostate cancer and the possible signaling pathways are getting increased day by day, and new treatment methods are being searched for. The aim of the present study is to investigate the effects of ferulic acid (FA), a phenolic compound, on cell cycle, apoptosis, invasion, and colony formation in the PC-3 and LNCaP prostate cancer cells. The effect of FA on cell viability was determined via a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) method. Total RNA was isolated with Tri Reagent. Expression of 84 genes for both cell cycle and apoptosis separately was evaluated by reverse transcriptase PCR (RT-PCR). Protein expressions were evaluated by Western blot analysis. Furthermore, apoptotic effects of FA were observed with terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) assay. Effects of FA on cell invasion and colony formation were determined using Matrigel chamber and colony assay, respectively. The half maximal inhibitory concentration (IC50) dose of FA was found to be 300 μM in PC-3 cells and 500 μM in LNCaP cells. According to RT-PCR results, it was observed that FA inhibited cell proliferation by increasing the gene expressions of ATR, ATM, CDKN1A, CDKN1B, E2F4, RB1, and TP53 and decreasing the gene expressions of CCND1, CCND2, CCND3, CDK2, CDK4, and CDK6 in PC-3 cells. On the other hand, it was seen that FA suppressed cell proliferation by increasing in the gene expressions of CASP1, CASP2, CASP8, CYCS, FAS, FASLG, and TRADD and decreasing in the gene expressions of BCL2 and XIAP in LNCaP cells. In this study, protein expression of CDK4 and BCL2 genes significantly decreased in these cells. It could induce apoptosis in PC-3 and LNCaP cells. Also, it was observed that FA suppressed the invasion in PC-3 and LNCaP cells. Moreover, it suppressed the colony formation. In conclusion, it has been observed that FA may lead to cell cycle arrest in PC-3 cells while it may cause apoptosis in LNCaP cells.
Coutinho-Camillo CM, Lourenço SV, de Araújo Lima L, et al.Expression of apoptosis-regulating miRNAs and target mRNAs in oral squamous cell carcinoma.
Cancer Genet. 2015 Jul-Aug; 208(7-8):382-9 [PubMed
] Related Publications
Aberrations in the apoptotic mechanisms that cause excessive or deficient programmed cell death have been linked to a wide array of pathological conditions. In this study, using real-time reverse transcriptase-PCR, we analyzed the expression of apoptosis-regulating miRNAs (miR-15a, miR-16, miR-17-5p, miR-20a, miR-21, miR-29a, and miR-34a) in 20 oral squamous cell carcinoma and 5 normal oral mucosa tissue samples. Bioinformatic algorithms were used to identify the target genes of these miRNAs (BCL2, CASP2, CASP7, CASP8, DIABLO). The expression transcript levels of the target genes were measured in 50 oral squamous cell carcinoma and 10 normal oral mucosa tissue samples. We observed downregulation of miR-15a, miR-29a, and miR-34a in 50, 75, and 70% of samples, respectively. miR-16, miR-17-5p, miR-20a, and miR-21 expression was normal in 80, 75, 90, and 60% of samples, respectively. BCL2 transcripts were downregulated in 60% of samples, and normal-like expression was observed for CASP2, CASP7, CASP8, and DIABLO transcripts in 66, 82, 68, and 60% of samples, respectively. BCL2 expression was negative to weak, and that of proteins CASP2, CASP7, CASP8, and DIABLO was moderate to strong. Our study provides evidence of alterations in the expression of apoptosis-regulating miRNAs and genes in the apoptotic pathway, demonstrating that regulation of apoptosis is a hallmark of oral squamous cell carcinoma pathogenesis.
microRNA-449a (miR-449a) has been identified to function as a tumor suppressor in several types of cancers. However, the role of miR-449a in neuroblastoma has not been intensively investigated. We recently found that the overexpression of miR-449a significantly induces neuroblastoma cell differentiation, suggesting its potential tumor suppressor function in neuroblastoma. In this study, we further investigated the mechanisms underlying the tumor suppressive function of miR-449a in neuroblastoma. We observed that miR-449a inhibits neuroblastoma cell survival and growth through 2 mechanisms--inducing cell differentiation and cell cycle arrest. Our comprehensive investigations on the dissection of the target genes of miR-449a revealed that 3 novel targets- MFAP4, PKP4 and TSEN15 -play important roles in mediating its differentiation-inducing function. In addition, we further found that its function in inducing cell cycle arrest involves down-regulating its direct targets CDK6 and LEF1. To determine the clinical significance of the miR-449a-mediated tumor suppressive mechanism, we examined the correlation between the expression of these 5 target genes in neuroblastoma tumor specimens and the survival of neuroblastoma patients. Remarkably, we noted that high tumor expression levels of all the 3 miR-449a target genes involved in regulating cell differentiation, but not the target genes involved in regulating cell cycle, are significantly correlated with poor survival of neuroblastoma patients. These results suggest the critical role of the differentiation-inducing function of miR-449a in determining neuroblastoma progression. Overall, our study provides the first comprehensive characterization of the tumor-suppressive function of miR-449a in neuroblastoma, and reveals the potential clinical significance of the miR-449a-mediated tumor suppressive pathway in neuroblastoma prognosis.
Zhang C, Fang X, Li W, et al.Influence of recombinant lentiviral vector encoding miR-15a/16-1 in biological features of human nasopharyngeal carcinoma CNE-2Z cells.
Cancer Biother Radiopharm. 2014; 29(10):422-7 [PubMed
] Related Publications
MicroRNAs can function as tumor suppressor miRNAs. Bcl-2 is an antiapoptotic gene overexpressed in many tumors, including nasopharyngeal carcinoma (NPC). It is reported that microRNA-15a (miR-15a) and microRNA-16-1 (miR-16-1) could act as bcl-2 inhibitors. To investigate their effects on NPC, the authors used recombinant lentiviral vector to upregulate the expression of miR-15a/16-1 in NPC CNE-2Z cells. The authors divided cells into the control group, transfection group, radiotherapy group, and transfection-radiotherapy group. In this experiment, reverse transcription-quantitative polymerase chain reaction was used to detect the expression of miR-15a/16-1 and bcl-2 mRNA. Cell proliferation was analyzed by MTT assay. Flow cytometry was used to measure cell apoptosis. Radiosensitivity was measured using colony-forming experiment. The protein expression of bcl-2 was measured by western blot, the activation levels of caspase were detected by a spectrophotometric method. After transfection, cell proliferation was inhibited, while the apoptosis rate and radiosensitivity were increased. In addition, the activation of caspase-2 and caspase-3 was aggrandized correspondingly. Although the expression levels of bcl-2 mRNA in each group had no difference, the protein expression of bcl-2 was downregulated. These results suggested that miR-15a/16-1 could inhibit cell proliferation and increase the apoptosis and radiosensitivity of CNE-2 cells, by regulating the bcl-2 gene at post-transcriptional level and by increasing the activation of caspase-2 and caspase-3.
Picco R, Tomasella A, Fogolari F, Brancolini CTranscriptomic analysis unveils correlations between regulative apoptotic caspases and genes of cholesterol homeostasis in human brain.
PLoS One. 2014; 9(10):e110610 [PubMed
] Free Access to Full Article Related Publications
Regulative circuits controlling expression of genes involved in the same biological processes are frequently interconnected. These circuits operate to coordinate the expression of multiple genes and also to compensate dysfunctions in specific elements of the network. Caspases are cysteine-proteases with key roles in the execution phase of apoptosis. Silencing of caspase-2 expression in cultured glioblastoma cells allows the up-regulation of a limited number of genes, among which some are related to cholesterol homeostasis. Lysosomal Acid Lipase A (LIPA) was up-regulated in two different cell lines in response to caspase-2 down-regulation and cells silenced for caspase-2 exhibit reduced cholesterol staining in the lipid droplets. We expanded this observation by large-scale analysis of mRNA expression. All caspases were analyzed in terms of co-expression in comparison with 166 genes involved in cholesterol homeostasis. In the brain, hierarchical clustering has revealed that the expression of regulative apoptotic caspases (CASP2, CASP8 CASP9, CASP10) and of the inflammatory CASP1 is linked to several genes involved in cholesterol homeostasis. These correlations resulted in altered GBM (Glioblastoma Multiforme), in particular for CASP1. We have also demonstrated that these correlations are tissue specific being reduced (CASP9 and CASP10) or different (CASP2) in the liver. For some caspases (CASP1, CASP6 and CASP7) these correlations could be related to brain aging.
Caspase-2 is an atypical caspase that regulates apoptosis, cell cycle arrest and genome maintenance, although the mechanisms are not well understood. Caspase-2 has also been implicated in chemotherapy response in lung cancer, but this function has not been addressed in vivo. Here we show that Caspase-2 functions as a tumor suppressor in Kras-driven lung cancer in vivo. Loss of Caspase-2 leads to enhanced tumor proliferation and progression. Despite being more histologically advanced, Caspase-2-deficient tumors are sensitive to chemotherapy and exhibit a significant reduction in tumor volume following repeated treatment. However, Caspase-2-deficient tumors rapidly rebound from chemotherapy with enhanced proliferation, ultimately hindering long-term therapeutic benefit. In response to DNA damage, Caspase-2 cleaves and inhibits Mdm2 and thereby promotes the stability of the tumor-suppressor p53. Caspase-2 expression levels are significantly reduced in human lung tumors with wild-type p53, in agreement with the model whereby Caspase-2 functions through Mdm2/p53 regulation. Consistently, p53 target genes including p21, cyclin G1 and Msh2 are reduced in Caspase-2-deficient tumors. Finally, we show that phosphorylation of p53-induced protein with a death domain 1 leads to Caspase-2-mediated cleavage of Mdm2, directly impacting p53 levels, activity and chemotherapy response. Together, these studies elucidate a Caspase-2-p53 signaling network that impacts lung tumorigenesis and chemotherapy response in vivo.
Caspase-2 has been implicated in various cellular functions, including cell death by apoptosis, oxidative stress response, maintenance of genomic stability and tumor suppression. The loss of the caspase-2 gene (Casp2) enhances oncogene-mediated tumorigenesis induced by E1A/Ras in athymic nude mice, and also in the Eμ-Myc lymphoma and MMTV/c-neu mammary tumor mouse models. To further investigate the function of caspase-2 in oncogene-mediated tumorigenesis, we extended our studies in the TH-MYCN transgenic mouse model of neuroblastoma. Surprisingly, we found that loss of caspase-2 delayed tumorigenesis in the TH-MYCN neuroblastoma model. In addition, tumors from TH-MYCN/Casp2(-/-) mice were predominantly thoracic paraspinal tumors and were less vascularized compared with tumors from their TH-MYCN/Casp2(+/+) counterparts. We did not detect any differences in the expression of neuroblastoma-associated genes in TH-MYCN/Casp2(-/-) tumors, or in the activation of Ras/MAPK signaling pathway that is involved in neuroblastoma progression. Analysis of expression array data from human neuroblastoma samples showed a correlation between low caspase-2 levels and increased survival. However, caspase-2 levels correlated with clinical outcome only in the subset of MYCN-non-amplified human neuroblastoma. These observations indicate that caspase-2 is not a suppressor in MYCN-induced neuroblastoma and suggest a tissue and context-specific role for caspase-2 in tumorigenesis.
Winkler C, Doller A, Imre G, et al.Attenuation of the ELAV1-like protein HuR sensitizes adenocarcinoma cells to the intrinsic apoptotic pathway by increasing the translation of caspase-2L.
Cell Death Dis. 2014; 5:e1321 [PubMed
] Free Access to Full Article Related Publications
Caspase-2 represents the most conserved member of the caspase family, which exhibits features of both initiator and effector caspases. Using ribonucleoprotein (RNP)-immunoprecipitation assay, we identified the proapoptotic caspase-2L encoding mRNA as a novel target of the ubiquitous RNA-binding protein HuR in DLD-1 colon carcinoma cells. Unexpectedly, crosslinking-RNP and RNA probe pull-down experiments revealed that HuR binds exclusively to the caspase-2-5' untranslated region (UTR) despite that the 3' UTR of the mRNA bears several adenylate- and uridylate-rich elements representing the prototypical HuR binding sites. By using RNAi-mediated loss-of-function approach, we observed that HuR regulates the mRNA and in turn the protein levels of caspase-2 in a negative manner. Silencing of HuR did not affect the stability of caspase-2 mRNA but resulted in an increased redistribution of caspase-2 transcripts from RNP particles to translational active polysomes implicating that HuR exerts a direct repressive effect on caspase-2 translation. Consistently, in vitro translation of a luciferase reporter gene under the control of an upstream caspase-2-5'UTR was strongly impaired after the addition of recombinant HuR, whereas translation of caspase-2 coding region without the 5'UTR is not affected by HuR confirming the functional role of the caspase-2-5'UTR. Functionally, an elevation in caspase-2 level by HuR knockdown correlated with an increased sensitivity of cells to apoptosis induced by staurosporine- and pore-forming toxins as implicated by their significant accumulation in the sub G1 phase and an increase in caspase-2, -3 and poly ADP-ribose polymerase cleavage, respectively. Importantly, HuR knockdown cells remained insensitive toward STS-induced apoptosis if cells were additionally transfected with caspase-2-specific siRNAs. Collectively, our findings support the hypothesis that HuR by acting as an endogenous inhibitor of caspase-2-driven apoptosis may essentially contribute to the antiapoptotic program of adenocarcinoma cells by HuR.
Zhang Q, Hu H, Shi X, Tang WKnockdown of S100P by lentiviral-mediated RNAi promotes apoptosis and suppresses the colony-formation ability of gastric cancer cells.
Oncol Rep. 2014; 31(5):2344-50 [PubMed
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S100P is a putative candidate oncogene in several types of human tumors. However, expression of S100P, its potential role and its clinical significance in gastric cancer remain unclear. In the present study, S100P expression was examined by immunohistochemistry using a tissue microarray. Positive staining for S100P was noted in 77.1% of the cases while 22.9% were negative. In two gastric cancer cell lines, MGC-803 and SGC-7901, S100P expression was knocked down by a lentiviral short hairpin delivery system. The RNA interference-mediated downregulation of S100P expression markedly promoted cell apoptosis and inhibited cell colony-formation ability of the gastric cancer cells. In addition, knockdown of S100P significantly regulated the expression of 12 apoptosis-associated genes with a >1.5-fold change compared with the negative control. Among them, FOS, DDIT3 and FN1 were significantly upregulated, while FASLG, DAPK1, CTNNB1 and CASP2 were notably downregulated following S100P silencing. These results suggest that S100P acts as an oncogenic factor in gastric cancer and is a potential molecular target for gastric cancer gene therapy.
Mfouo-Tynga I, Houreld NN, Abrahamse HInduced cell death pathway post photodynamic therapy using a metallophthalocyanine photosensitizer in breast cancer cells.
Photomed Laser Surg. 2014; 32(4):205-11 [PubMed
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OBJECTIVE: Zinc phthalocyanine (ZnPcSmix) was used as the photosensitizer (PS) in this study to investigate the cell death patterns as a result of photodynamic therapy (PDT) in a breast cancer cell line (MCF-7) in vitro using a 680 nm diode laser at a fluence of 5 J/cm(2).
BACKGROUND: PDT is a noninvasive form of cancer therapy, successfully applied for the treatment of various cancer types.
METHODS: Flow cytometry using Annexin V-fluorescein isothiocyanate (FITC), a cell death immunosorbent assay (ELISA), and gene expression analysis following ZnPcSmix mediated PDT were performed to determine the induced cell death pathways.
RESULTS: The apoptotic cells abounded after the treatment, nuclear fragmentation was seen as oligonucleosomal degradation and increased expression of the B-cell lymphoma 2 (Bcl-2), DNA fragmentation factor alpha (DFFA1), and caspase 2 (CASP2) genes, indicated that apoptosis is the main induced mode of cell death.
CONCLUSIONS: ZnPcSmix mediated PDT led to an apoptotic cell death pathway and the PS used showed its ability to stimulate and initiate programmed cell death.
Caspase-2 (casp-2) is the most conserved caspase across species, and is one of the initiator caspases activated by various stimuli. The casp-2 gene produces several alternative splicing isoforms. It is believed that the long isoform, casp-2L, promotes apoptosis, whereas the short isoform, casp-2S, inhibits apoptosis. The actual effect of casp-2S on apoptosis is still controversial, however, and the underlying mechanism for casp-2S-mediated apoptosis inhibition is unclear. Here, we analyzed the effects of casp-2S on DNA damage induced apoptosis through "gain-of-function" and "loss-of-function" strategies in ovarian cancer cell lines. We clearly demonstrated that the over-expression of casp-2S inhibited, and the knockdown of casp-2S promoted, the cisplatin-induced apoptosis of ovarian cancer cells. To explore the mechanism by which casp-2S mediates apoptosis inhibition, we analyzed the proteins which interact with casp-2S in cells by using immunoprecipitation (IP) and mass spectrometry. We have identified two cytoskeleton proteins, Fodrin and α-Actinin 4, which interact with FLAG-tagged casp-2S in HeLa cells and confirmed this interaction through reciprocal IP. We further demonstrated that casp-2S (i) is responsible for inhibiting DNA damage-induced cytoplasmic Fodrin cleavage independent of cellular p53 status, and (ii) prevents cisplatin-induced membrane blebbing. Taken together, our data suggests that casp-2S affects cellular apoptosis through its interaction with membrane-associated cytoskeletal Fodrin protein.
Spontaneous regression of neuroblastoma (NB) resembles the developmentally regulated programmed cell death (PCD) of sympathetic neurons. Regressing tumor cells express high levels of the nerve growth factor (NGF) receptors TRKA and p75NTR and are dependent on NGF for survival; however, the underlying molecular mechanism remains elusive. Here, we show that UNC5D, a dependence receptor that is directly targeted by p53 family members, is highly expressed in favorable NBs. NGF withdrawal strongly upregulated UNC5D, E2F1, and p53 in human primary favorable NBs. The induced UNC5D was cleaved by caspases 2/3, and the released intracellular fragment translocated into the nucleus and interacted with E2F1 to selectively transactivate the proapoptotic target gene. The cleavage of UNC5D and its induction of apoptosis were strongly inhibited by addition of netrin-1. Unc5d(-/-) mice consistently exhibited a significant increase in dorsal root ganglia neurons and resistance to NGF depletion-induced apoptosis in sympathetic neurons compared with wild-type cells. Our data suggest that UNC5D forms a positive feedback loop with p53 and E2F1 to promote NGF dependence-mediated PCD during NB regression.
Song T, Zhang X, Zhang L, et al.miR-708 promotes the development of bladder carcinoma via direct repression of Caspase-2.
J Cancer Res Clin Oncol. 2013; 139(7):1189-98 [PubMed
] Related Publications
PURPOSE: Bladder cancer is one of the world's top ten malignant tumors. The crucial role of microRNA in carcinogenesis has been well emphasized. Considering miRNA expression was tumor stage-, tissue-, or even development-specific, more experimental evidences about the functions of miRNAs in bladder cancer should be discovered to advance applying of miRNA in the diagnosis or therapy of cancer.
METHODS: MiR-708 level in bladder carcinoma and adjacent noncancerous tissues was tested by real-time qPCR. Cell apoptosis was analyzed by using flow cytometry. The tumorigenicity of bladder carcinoma cells was evaluated in nude mice model. Luciferase reporter gene assays were performed to identify the interaction between miR-708 and 3'UTR of Caspase-2 mRNA. The protein level of Caspase-2 was determined by western blotting.
RESULTS: In this study, we reported that miR-708 was frequently dysregulated in human bladder carcinoma tissues compared to normal tissues. In addition, we found that silencing of miR-708 could promote the T24 and 5637 cells to apoptosis and inhibit the bladder tumor growth in vivo. Also, Caspase-2 was proved to be one of direct targets of miR-708 in T24 and 5637 cells. Further results showed that Caspase-2 was involved in the miR-708 regulated cell apoptosis.
CONCLUSIONS: All together, these results suggest miR-708 may act as an oncogene and induce the carcinogenicity of bladder cancer by down-regulating Caspase-2 level.
Ehrlichova M, Mohelnikova-Duchonova B, Hrdy J, et al.The association of taxane resistance genes with the clinical course of ovarian carcinoma.
Genomics. 2013; 102(2):96-101 [PubMed
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Taxane and platinum-based chemotherapy regimens are standard treatment for advanced ovarian carcinoma. Expression levels of putative markers of taxane resistance in carcinoma tissues and paired peritoneal samples (n=55) and in 16 samples of ovaries without signs of carcinoma were compared with clinical data and the patients' time to progression. KIF14, PRC1, CIT and ABCC1 genes were significantly overexpressed in carcinomas when compared with normal ovarian tissues, while ABCB1 and CASP9 expression was decreased. Associations of protein expression of the proliferation marker Ki-67 with KIF14, PRC1, ABCB1 and CASP2 were found. Lastly, it was discovered that ABCB1 and CASP2 levels associated with FIGO stage and that the CIT level associated with the time to progression of ovarian carcinoma patients (P<0.0001). In conclusion, ABCB1, CASP2, KIF14, PRC1 and CIT genes seem to associate with surrogate markers of ovarian carcinoma progression and CIT gene associates with therapy outcome.
Brynychová V, Hlaváč V, Ehrlichová M, et al.Importance of transcript levels of caspase-2 isoforms S and L for breast carcinoma progression.
Future Oncol. 2013; 9(3):427-38 [PubMed
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AIM: A role of caspase-2 in chemotherapy-induced apoptosis has been suggested. Our study aimed to evaluate the prognostic and predictive importance of caspase-2 isoforms in breast cancer patients.
MATERIALS & METHODS: Caspase-2L and -2S transcript levels were determined in paired tumor and non-malignant control tissues from 64 patients after neoadjuvant chemotherapy and 100 pretreatment patients (general set) by real-time PCR with absolute quantification.
RESULTS: Low but statistically significant upregulation of caspase-2L in tumor versus control tissues was observed in both sets. Significant associations of the levels of caspase-2L, -2S or S/L ratio with clinical prognostic factors were observed. However, none of these associations were confirmed in both sets. Levels of caspase-2 isoforms or the S/L ratio did not significantly associate with progression-free survival in the general set or with chemotherapy response in the neoadjuvant set.
CONCLUSION: Our results suggest that the role of caspase-2 isoforms in the progression of breast cancer may considerably differ between pre- and post-chemotherapy patients.
The cisplatin-induced ATM-dependent phosphorylated (p)-ΔNp63α plays an important role in transcriptional regulation of specific genes encoding mRNAs and microRNAs (miRs) implicated in cell death, cell survival, and chemoresistance. The p-ΔNp63α-induced miR-885-3p functions as a critical regulator of MDM4, ATK1, BCL2, ATG16L2, ULK2, CASP2, and CASP3 mRNAs via pairing with their respective 'recognition' sequences. Cisplatin exposure modulated the levels of target proteins (reduced BCL2, AKT1, ATG16L2, and ULK2, while activated MDM4) in cisplatin-sensitive wild type ΔNp63α cells leading to distinct changes in cell viability. Finally, miR-885-3p modulated the cisplatin-induced TP53-dependent mitochondrial apoptosis by up regulation of MDM4 levels and down regulation of BCL2 levels in mitochondria. Altogether, our results support the notion that miR-885-3p might contribute in regulation of cell viability, apoptosis and/or autophagy in squamous cell carcinoma cells upon cisplatin exposure.
Yoo BH, Wang Y, Erdogan M, et al.Oncogenic ras-induced down-regulation of pro-apoptotic protease caspase-2 is required for malignant transformation of intestinal epithelial cells.
J Biol Chem. 2011; 286(45):38894-903 [PubMed
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Resistance of carcinoma cells to anoikis, apoptosis that is normally induced by loss of cell-to-extracellular matrix adhesion, is thought to be essential for the ability of these cells to form primary tumors, invade adjacent tissues, and metastasize to distant organs. Current knowledge about the mechanisms by which cancer cells evade anoikis is far from complete. In an effort to understand these mechanisms, we found that ras, a major oncogene, down-regulates protease caspase-2 (which initiates certain steps of the cellular apoptotic program) in malignant human and rat intestinal epithelial cells. This down-regulation could be reversed by inhibition of a protein kinase Mek, a mediator of Ras signaling. We also found that enforced down-regulation of caspase-2 in nonmalignant intestinal epithelial cells by RNA interference protected them from anoikis. Furthermore, the reversal of the effect of Ras on caspase-2 achieved by the expression of exogenous caspase-2 in detached ras-transformed intestinal epithelial cells promoted well established apoptotic events, such as the release of the pro-apoptotic mitochondrial factors cytochrome c and HtrA2/Omi into the cytoplasm of these cells, significantly enhanced their anoikis susceptibility, and blocked their long term growth in the absence of adhesion to the extracellular matrix. Finally, the blockade of the effect of Ras on caspase-2 substantially suppressed growth of tumors formed by the ras-transformed cells in mice. We conclude that ras-induced down-regulation of caspase-2 represents a novel mechanism by which oncogenic Ras protects malignant intestinal epithelial cells from anoikis, promotes their anchorage-independent growth, and allows them to form tumors in vivo.
Lamers F, van der Ploeg I, Schild L, et al.Knockdown of survivin (BIRC5) causes apoptosis in neuroblastoma via mitotic catastrophe.
Endocr Relat Cancer. 2011; 18(6):657-68 [PubMed
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BIRC5 (survivin) is one of the genes located on chromosome arm 17q in the region that is often gained in neuroblastoma. BIRC5 is a protein in the intrinsic apoptotic pathway that interacts with XIAP and DIABLO leading to caspase-3 and caspase-9 inactivation. BIRC5 is also involved in stabilizing the microtubule-kinetochore dynamics. Based on the Affymetrix mRNA expression data, we here show that BIRC5 expression is strongly upregulated in neuroblastoma compared with normal tissues, adult malignancies, and non-malignant fetal adrenal neuroblasts. The over-expression of BIRC5 correlates with an unfavorable prognosis independent of the presence of 17q gain. Silencing of BIRC5 in neuroblastoma cell lines by various antisense molecules resulted in massive apoptosis as measured by PARP cleavage and FACS analysis. As both the intrinsic apoptotic pathway and the chromosomal passenger complex can be therapeutically targeted, we investigated in which of them BIRC5 exerted its essential anti-apoptotic role. Immunofluorescence analysis of neuroblastoma cells after BIRC5 silencing showed formation of multinucleated cells indicating mitotic catastrophe, which leads to apoptosis via P53 and CASP2. We show that BIRC5 silencing indeed resulted in activation of P53 and we could rescue apoptosis by CASP2 inhibition. We conclude that BIRC5 stabilizes the microtubules in the chromosomal passenger complex in neuroblastoma and that the apoptotic response results from mitotic catastrophe, which makes BIRC5 an interesting target for therapy.
Ulybina YM, Kuligina ES, Mitiushkina NV, et al.Distribution of coding apoptotic gene polymorphisms in women with extreme phenotypes of breast cancer predisposition and tolerance.
Tumori. 2011 Mar-Apr; 97(2):248-51 [PubMed
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AIMS AND BACKGROUND: Comparison of subjects with extreme phenotypes of cancer susceptibility and tolerance allows to detect low-penetrance gene-disease interactions with a relatively small study size.
METHODS AND STUDY DESIGN: We analyzed the distribution of 19 coding apoptotic gene polymorphisms (Bid Gly10Ser; Casp2 Leu141Val; Casp5 Ala90Thr and Val318Leu; Casp7 Glu255Asp; Casp8 His302Asp; Casp9 Val28Ala, His173Arg and Arg221Gln; Casp10 Ile479Leu; Faim Thr117Ala and Ser127Leu; DR4 Arg141His, Thr209Arg, Ala228Glu and Lys441Arg; Survivin Lys129Glu; TNFR1 Gln121Arg; XIAP Pro423Gln) in 121 breast cancer patients with clinical features of a hereditary predisposition (family history and/or early onset and/or bilaterality) and 142 elderly tumor-free women.
RESULTS: None of the individual single nucleotide polymorphisms (SNPs) demonstrated an association with breast cancer risk. The analysis of gene interactions revealed that the combination of XIAP Pro423Gln (rs5956583) AA genotype with Casp7 Glu255Asp (rs2227310) CG genotype appeared to prevail in "supercases" relative to "supercontrols" (25/121 [21%] vs 11/142 [8%], P = 0.002). We attempted to validate this association in the second round of case-control analysis, which involved 519 randomly selected breast cancer patients and 509 age-matched healthy women, but no difference was detected upon this comparison.
CONCLUSIONS: Coding apoptotic gene polymorphisms do not play a major role in BC predisposition. The results of this investigation may be considered while designing future studies on breast cancer-associated candidate SNPs.
Seo HW, Rengaraj D, Choi JW, et al.The expression profile of apoptosis-related genes in the chicken as a human epithelial ovarian cancer model.
Oncol Rep. 2011; 25(1):49-56 [PubMed
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The purpose of our study was to examine the expression pattern of apoptosis-related genes in normal and cancerous ovaries of the hen. Localization of apoptosis-related gene mRNA was investigated in cancerous ovaries using in situ hybridization. The expression patterns of apoptosis-related genes were confirmed with RT-PCR in normal and cancerous ovaries. Differences of expression level between normal ovaries and ovarian cancers were analyzed using quantitative RT-PCR. In both normal and cancerous chicken ovaries, the expression of CASP1, CASP2, CASP3, CASP6, CASP8 and CASP9 were detected through RT-PCR analysis. The expression of BCL2, BCL2L1 and BID were confirmed in normal and cancerous ovaries of the hen. Quantitative RT-PCR showed that CASP1 expression was significantly increased in cancerous ovaries compared with normal ovaries, whereas BID expression was decreased. Our results showed a resistance to removal of abnormal cells via apoptosis in cancerous ovaries of the hen. Collectively, this phenomenon is closely associated with the dysregulation of CASP1 and BID expression in chicken ovarian cancer.