We report the first patient (a 13-year-old girl) with a sinonasal low-grade non-intestinal-type adenocarcinoma showing aberrant CDX2 expression both within morular areas and in the tubular component and demonstrate for the first time a SYN2-PPARG gene fusion in this tumor type. The tumor arose from the nasal septum and had not spread beyond the nasal cavity.

BACKGROUND: High-grade serous carcinoma, a representative high-grade ovarian carcinoma, is believed to be closely associated with a TP53 mutation. Recently, this category of ovarian carcinoma has gained increasing attention owing to the recognition of morphological varieties of TP53-mutated high-grade ovarian carcinoma. Herein, we report the case of a patient with high-grade serous carcinoma with mucinous differentiation.
CASE PRESENTATION: A 59-year-old postmenopausal woman was referred to the gynecologist because of abnormal vaginal bleeding. The radiological assessment revealed an intrapelvic multicystic mass, which was interpreted as an early right ovarian cancer and then removed by radical surgery. Histologically, the cancer cells were found in the bilateral ovaries and para-aortic lymph nodes. The cancer cells showed high-grade nuclear atypia and various morphologies, including the solid, pseudo-endometrioid, transitional cell-like (SET) pattern, and mucin-producing patterns. Benign and/or borderline mucin-producing epithelium, serous tubal intraepithelial carcinoma, and endometriosis-related lesions were not observed. In immunohistochemistry analyses, the cancer cells were diffuse positive for p53; block positive for p16; partial positive for WT1, ER, PgR, CDX2 and PAX8; and negative for p40, p63, GATA3, Napsin A, and vimentin. The Ki-67 labeling index of the cancer cells was 60-80%. Direct sequencing revealed that the cancer cells contained a missense mutation (c.730G>A) in the TP53 gene.
CONCLUSION: Mucinous differentiation in high-grade serous carcinoma is a rare and unique ovarian tumor phenotype and it mimics the phenotypes of mucinous or seromucinous carcinoma. To avoid the misdiagnosis, extensive histological and immunohistochemical analyses should be performed when pathologists encounter high-grade mucin-producing ovarian carcinoma. The present case shows that the unusual histological characteristic of high-grade serous carcinoma, the "SET" feature, could be extended to the solid, transitional, endometrioid and mucinous-like (STEM) feature.

The diagnosis of neuroendocrine neoplasia (NEN) is often made at an advanced stage of disease, including hepatic metastasis. At this point, the primary may still be unknown and sometimes cannot even be detected by functional imaging, especially in very small tumors of the pancreas (pan) and small intestinal (si) entities. The site of the primary may be based on biopsy specimens of the liver applying a specific set of markers. Specimens of liver metastases from 87 patients with NENs were studied. In retrospect, 50 patients had si and 37 pan NENs. Tissue samples were evaluated by immunohistochemistry. The markers applied were insulin gene enhancer protein Islet-1 (ISL-1), homeobox protein CDX-2 (CDX2), thyroid transcription factor 1 (TTF-1), and serotonin. Positive stains for CDX2 were documented in 43 (86%) and for serotonin in 45 (90%) of 50 siNENs. Three panNENs were positive for CDX2 and one for serotonin, respectively. ISL-1 was negative throughout in siNENs and also negative in 8 of 50 panNENs (21.6%). TTF-1 was negative in more than 90% of the specimens of either entity. Immunohistochemical markers in liver metastasis can lead the way to the site of the primary NEN. They should always be used in combined clusters.

Intestinal metaplasia induced by ectopic expression of caudal-type homeobox (CDX)2 and/or CDX1 (CDX) is frequently observed around gastric cancer (GC). Abnormal expression of CDX is also observed in GC and suggests that inappropriate gastrointestinal differentiation plays essential roles in gastric tumorigenesis, but their roles on tumorigenesis remain unelucidated. Publicly available databases show that GC patients with higher CDX expression have significantly better clinical outcomes. We introduced CDX2 and CDX1 genes separately into GC-originated MKN7 and TMK1 cells deficient in CDX. Marked suppression of cell growth and dramatic morphological change into spindle-shaped flat form were observed along with induction of intestinal marker genes. G0-G1 growth arrest was accompanied by changed expression of cell cycle-related genes but not with apoptosis or senescence. Microarray analyses additionally showed decreased expression of gastric marker genes and increased expression of stemness-associated genes. Hierarchical clustering of 111 GC tissues and 21 non-cancerous gastric tissues by selected 18 signature genes based on our transcriptome analyses clearly categorized the 132 tissues into non-cancer, "CDX signature"-positive GC, and "CDX signature"-negative GC. Gene set enrichment analysis indicated that "CDX signature"-positive GC has lower malignant features. Immunohistochemistry of 89 GC specimens showed that 50.6% were CDX2-deficient, 66.3% were CDX1-deficient, and 44.9% were concomitant CDX2/CDX1-deficient, suggesting that potentially targetable GC cases by induced intestinal differentiation are quite common. In conclusion, exogenous expression of CDX2/CDX1 can lead to efficient growth inhibition of CDX-deficient GC cells. It is based on rapidly induced intestinal differentiation, which may be a future therapeutic strategy.

BACKGROUND: In colorectal cancer, CDX2 expression is lost in approximately 20% of cases and associated with poor outcome. Here, we aim to validate the clinical impact of CDX2 and investigate the role of promoter methylation and histone deacetylation in CDX2 repression and restoration.
METHODS: CDX2 immunohistochemistry was performed on multi-punch tissue microarrays (n = 637 patients). Promoter methylation and protein expression investigated on 11 colorectal cancer cell lines identified two CDX2 low expressors (SW620, COLO205) for treatment with decitabine (DNA methyltransferase inhibitor), trichostatin A (TSA) (general HDAC inhibitor), and LMK-235 (specific HDAC4 and HDAC5 inhibitor). RNA and protein levels were assessed. HDAC5 recruitment to the CDX2 gene promoter region was tested by chromatin immunoprecipitation.
RESULTS: Sixty percent of tumors showed focal CDX2 loss; 5% were negative. Reduced CDX2 was associated with lymph node metastasis (p = 0.0167), distant metastasis (p = 0.0123), and unfavorable survival (multivariate analysis: p = 0.0008; HR (95%CI) 0.922 (0.988-0.997)) as well as BRAF
CONCLUSION: CDX2 loss is an adverse prognostic factor and linked to molecular features of the serrated pathway. RNA/protein expression is restored in CDX2 low-expressing CRC cell lines by demethylation and HDAC inhibition. Importantly, our data underline HDAC4 and HDAC5 as new epigenetic CDX2 regulators that warrant further investigation.

BACKGROUND: The expression profile of immunohistochemical markers of origin in poorly differentiated neuroendocrine carcinoma (PDNEC) is not well studied.
MATERIALS AND METHODS: Seventy-four PDNECs from gastroenteropancreatic (GEP) organs and the lung, including 48 large cell NEC (LCNEC) and 26 small cell carcinomas (SmCC), were subject to immunohistochemical staining for CDX2, TTF1 and ISL1. The staining intensity (1 to 3) and percentage of positive tumor cells [0 (negative), 1 (<50%) and 2 (≥50%)] were assessed. The multiplicative index (maximum 6) was calculated and the average total score (aTS) was determined for each primary site and histologic subtype.
RESULTS: In the 38 GEP and 36 lung PDNECs, CDX2, TTF1 and ISL1 staining was observed in 71% (aTS 2.8), 16% (aTS 0.4), 63% (aTS 1.9), and 22% (aTS 0.6), 72% (aTS 2.9) and 92% (aTS 3.8), respectively. GEP PDNECs showed a higher aTS for CDX2 and lower aTS for TTF1 and ISL1, compared to that of lung PDNECs (Student's t-test, p < 0.001). SmCC had a higher aTS for TTF1 and ISL1 (p < 0.001) and lower aTS for CDX2 (p < 0.002) than that of LCNEC.
CONCLUSIONS: CDX2 and TTF1 demonstrate potential utility in suggesting the primary site of PDNEC. In addition, CDX2 may be useful in supporting the diagnosis of LCNEC in cases with overlapping or borderline morphology. Utility of ISL1 as an adjunctive diagnostic marker of SmCC remains to be studied.

Colorectal adenomas are common precancerous lesions with the potential for malignant transformation to colorectal adenocarcinoma. Endoscopic polypectomy provides an opportunity for cancer prevention; however, recurrence rates are high. We collected formalin-fixed paraffin-embedded tissue of 15 primary adenomas with recurrence, 15 adenomas without recurrence, and 14 matched pair samples (primary adenoma and the corresponding recurrent adenoma). The samples were analysed by array-comparative genomic hybridisation (aCGH) and single-cell multiplex interphase fluorescence in situ hybridisation (miFISH) to understand clonal evolution, to examine the dynamics of copy number alterations (CNAs) and to identify molecular markers for recurrence prediction. The miFISH probe panel consisted of 14 colorectal carcinogenesis-relevant genes (COX2, PIK3CA, APC, CLIC1, EGFR, MYC, CCND1, CDX2, CDH1, TP53, HER2, SMAD7, SMAD4 and ZNF217), and a centromere probe (CEP10). The aCGH analysis confirmed the genetic landscape typical for colorectal tumorigenesis, that is, CNAs of chromosomes 7, 13q, 18 and 20q. Focal aberrations (≤10 Mbp) were mapped to chromosome bands 6p22.1-p21.33 (33.3%), 7q22.1 (31.4%) and 16q21 (29.4%). MiFISH detected gains of EGFR (23.6%), CDX2 (21.8%) and ZNF217 (18.2%). Most adenomas exhibited a major clone population which was accompanied by multiple smaller clone populations. Gains of CDX2 were exclusively seen in primary adenomas with recurrence (25%) compared to primary adenomas without recurrence (0%). Generation of phylogenetic trees for matched pair samples revealed four distinct patterns of clonal dynamics. In conclusion, adenoma development and recurrence are complex genetic processes driven by multiple CNAs whose evaluations by miFISH, with emphasis on CDX2, might serve as a predictor of recurrence.

Colorectal cancers (CRCs) harbor accumulated defects in key signaling pathways that regulate cell phenotypes, including proliferation, survival, metabolism, and differentiation. To study the functional contributions of the accumulated molecular defects in CRC, we have developed approaches to inactivate selected tumor suppressor and/or activate oncogenes in mouse colon epithelium. Conditional inactivation of the CDX2 tumor suppressor protein in conjunction with oncogenic activation of the BRAF protein promotes development of serrated glandular benign and malignant tumors in the mouse colon. The mouse tumors share significant morphological and molecular relationships with the 8% to 10% of human CRCs that manifest serrated morphology at diagnosis. The gene and protein expression patterns in the mouse tumors have informed understanding of the relationships between benign and malignant human serrated colon tumors. Our findings are consistent with prior work suggesting that perhaps upwards of one-third of human CRCs may arise from a precursor lesion with serrated morphology rather than a conventional adenoma.

BACKGROUND/AIMS: Long non-coding RNA maternally expressed gene 3 (MEG3) has been reported to play an essential role in cancer progression and metastasis. However, the overall biological role and regulatory mechanism of MEG3 in multiple myeloma (MM) development and progression remains largely ill-defined.
METHODS: MEG3 and miR-181a expression of MM patients were analyzed by publicly available MM data sets. Cell counting kit-8 and flow cytometry analysis were used to identify the function of MEG3 on MM in vitro. Additionally, we conducted tumor formation experiments in mice models to explain the role of MEG3 on MM in vivo. Then, several mechanism experiments, including dual-luciferase reporter assay and RNA immunoprecipitation were performed to evaluate the emulative relationship between MEG3 and miR-181a.
RESULTS: In this research, we found that MEG3 was downregulated in MM patients, which was linked with tumor progression. In addition, we demonstrated that miR-181a was overexpressed in MM patients in consistent with its cancer-promoting function. Importantly, several mechanism experiments revealed that MEG3, acting as an endogenous competitive RNA, could contend with miR-181a to inhibit tumor progression. Furthermore, as the target mRNA of miR-181a, homeobox gene A11(HOXA11) could be positively regulated by MEG3 through sponging miR-181a competitively in vitro.
CONCLUSION: Our present work supplies the first discovery of a MEG3/miR-181a/HOXA11 regulatory network in MM and highlights that MEG3 may serve as a promising target for MM therapy in the future.

CDX2 gene encodes a transcription factor involved in primary embryogenesis and hematopoietic development; however, the expression of CDX2 in adults is restricted to intestine and is not observed in blood tissues. The ectopic expression of CDX2 has been frequently observed in acute myeloid and lymphoid leukemia which in most cases is concomitant with poor prognosis. Induction of CDX2 in mice leads to hematologic complications, showing the leukemogenic origin of this gene. CDX2 plays significant role in the most critical pathways as the regulator of important transcription factors targeting cell proliferation, multi-drug resistance and survival. On the whole, the results indicate that CDX2 has the potential to be suggested as the diagnostic marker in hematologic malignancies. This review discusses the role of aberrant expression of CDX2 in the prognosis and the response to treatment in patients with different leukemia in clinical reports in the recent decades. The improvement in this regard could be of high importance in diagnosis and treatment methods.

BACKGROUND: Genetic alterations and epigenetic modifications are two main factors involved in gastric carcinogenesis, progression, and metastasis. Several miRNAs such as miRNA-9 and miRNA-326 may play important role in gastric cancer by targeting the 3'UTR of the caudal type homeobox (CDX) 1 and 2 mRNA respectively. The use of herbal medicines has been widely considered in the treatment of cancers such as gastric cancer. Sulforaphane extracted from broccoli may indirectly prevent cancer through affecting different signaling pathways. The aim of this study was to evaluate the effect of different concentrations of sulforaphane extracted from broccoli sprout (SEBS) on viability, death pattern, and expression alterations of CDX1/2 as well as miRNA-9 and miRNA-326 in normal (HF2FF) and gastric cancer cell lines.
METHODS: Two gastric cancer cell lines (AGS and MKN45) and HF2FF normal cell line were cultured and treated with different concentrations (31.25, 62.5, 125, and 250 μg/ml) of the purified sulforaphane. Expression levels of CDX1 and CDX2 as well as miRNA-9 and miRNA-326, and mechanisms leading to cell death were assessed by Taqman real time PCR assay and flow cytometry, respectively.
RESULTS: Significant dose-dependent and anti-proliferative effects of the SEBS were observed on AGS and MKN45 cells after 48 h with an IC50 value of about 112 and 125 μg/ml, respectively (P < 0.001). Apoptotic cells were observed in AGS and MKN45 cells but not HF2FF after 48 h of treatment with SEBS. Furthermore, significant changes in expression of CDX1, CDX2, miR-9 and miR-326 in the gastric cancer lines (AGS and MKN45), were observed under different concentrations of SEBS.
CONCLUSION: Our present study suggests that the SEBS may influence gastric cancer cell lines at specific doses and change their proliferation rate by altering the expression of CDX1, CDX2, miR-9, and miR-326.

BACKGROUND: To identify the most suitable genetic model for detecting the risk of breast cancer (BC)/ovarian cancer (OC) in specific populations.
METHODS: Databases were searched for related studies published up to October 2017. First, VDR genetic polymorphisms were compared in patients with and without cancer. Second, a network meta-analysis was used to reveal the relation between VDR genetic polymorphisms with disease outcomes. Subgroup analyses and a meta-regression were performed according to cancer types, ethnicity and genotypic method. The study is registered in PROSPERO with an ID: CRD42017075505.
RESULTS: Forty-five studies were eligible, which included 65,754 patients and 55 clinical analyses. Of genetic models, results suggested that the recessive model with the CDX2 polymorphism predicted the risk of BC in all cases. The recessive polymorphism model with the rs2228570 (FokI) polymorphism seemed to the best predictor of BC in Caucasian patients, whereas the homozygote model with the CDX2 polymorphism appeared to best predict BC in African-American patients. The homozygote model with the rs2228570 (FokI) polymorphism model appeared to detect the risk of OC in all cases, whereas the heterozygote model with the rs1544410 (BsmI) polymorphism seemed to detect the risk of OC in Caucasian patients.
CONCLUSIONS: By detecting the risk of BC, the recessive model with the rs2228570 (FokI) polymorphism is likely the best genetic model in Caucasian patients, and the homozygote model with the CDX2 polymorphism appears to be best genetic model in African-American patients. Moreover, for detecting clinical risk of OC, heterozygote models with the rs1544410 (BsmI) polymorphism is likely the best genetic model for detecting the risk of OC in Caucasian patients.

Sequencing of primary colorectal tumors has identified a gene fusion in approximately 3% of colorectal cancer patients of the VTI1A and TCF7L2 genes, encoding a VTI1A-TCF4 fusion protein containing a truncated TCF4. As dysregulation of the Wnt signaling pathway is associated with colorectal cancer development and progression, the functional properties and transcriptional regulation of the VTI1A-TCF4 fusion protein may also play a role in these processes. Functional characteristics of the VTI1A-TCF4 fusion protein in Wnt signaling were analyzed in NCI-H508 and LS174T colon cancer cell lines. The NCI-H508 cell line, containing the VTI1A-TCF7L2 fusion gene, showed no active Wnt signaling, and overexpression of the VTI1A-TCF4 fusion protein in LS174T cells along with a Wnt signaling luciferase reporter plasmid showed inhibition of activity. The transcriptional regulation of the VTI1A-TCF4 fusion gene was investigated in LS174T cells where the activity of the VTI1A promoter was compared to that of the TCF7L2 promoter, and the transcription factor CDX2 was analyzed for gene regulatory activity of the VTI1A promoter through luciferase reporter gene assay using colon cancer cell lines as a model. Transfection of LS174T cells showed that the VTI1A promoter is highly active compared to the TCF7L2 promoter, and that CDX2 activates transcription of VTI1A. These results suggest that the VTI1A-TCF4 fusion protein is a dominant negative regulator of the Wnt signaling pathway, and that transcription of VTI1A is activated by CDX2.

CDX2 is routinely used for identifying gastrointestinal origin of metastatic adenocarcinomas; but a high percentage of other carcinomas also show positivity with this antibody. SATB2 is a new immunohistochemical marker with a few studies showing that it is specifically expressed in a large majority of colorectal adenocarcinomas. We assessed SATB2 along with CDX2 in patient material with metastasis in order to determine whether the primary site could be identified as 'colon-rectum'. Metastasis in 67 liver biopsies, 108 lymph nodes from resection specimens and 36 serous effusions was analyzed retrospectively. Blinded slides stained for CDX2 and SATB2 were assessed individually by two pathologists and sensitivity, specificity and kappa statistics were calculated. Sensitivity for CDX2 in metastasis from colorectal adenocarcinomas was 93%; while in SATB2 it was 79%. The combination of CDX2 and SATB2 yielded a sensitivity of 79% and a high specificity of 93%. There was an acceptable level of agreement (κ = 0.64) between the pathologists for both the markers in case of colorectal adenocarcinoma metastasis. CDX2 is a sensitive marker compared to SATB2; while the specificity of combination of CDX2 and SATB2 is high for metastasis from colorectal adenocarcinoma. SATB2 can be used as a supplementary marker along with CDX2 to identify colorectal origin for material received from patients clinically presenting with metastasis.

We aimed to refine the value of CDX2 as an independent prognostic and predictive biomarker in colorectal cancer (CRC) according to disease stage and chemotherapy sensitivity in preclinical models. CDX2 expression was evaluated in 1045 stage I-IV primary CRCs by gene expression (n = 403) or immunohistochemistry (n = 642) and in relation to 5-year relapse-free survival (RFS), overall survival (OS), and chemotherapy. Pharmacogenomic associations between CDX2 expression and 69 chemotherapeutics were assessed by drug screening of 35 CRC cell lines. CDX2 expression was lost in 11.6% of cases and showed independent poor prognostic value in multivariable models. For individual stages, CDX2 was prognostic only in stage IV, independent of chemotherapy. Among stage I-III patients not treated in an adjuvant setting, CDX2 loss was associated with a particularly poor survival in the BRAF-mutated subgroup, but prognostic value was independent of microsatellite instability status and the consensus molecular subtypes. In stage III, the 5-year RFS rate was higher among patients with loss of CDX2 who received adjuvant chemotherapy than among patients who did not. The CDX2-negative cell lines were significantly more sensitive to chemotherapeutics than CDX2-positive cells, and the multidrug resistance genes MDR1 and CFTR were significantly downregulated both in CDX2-negative cells and in patient tumors. Loss of CDX2 in CRC is an adverse prognostic biomarker only in stage IV disease and appears to be associated with benefit from adjuvant chemotherapy in stage III. Early-stage patients not qualifying for chemotherapy might be reconsidered for such treatment if their tumor has loss of CDX2 and mutated BRAF.

This study was aimed to incorporate PCR testing in the determination of organ/tissue origin for cancers of unknown primary site (CUP). We developed a PCR panel consisting of 7 expression markers (CDX2, CDH17, SPB, UGRP, MAM, LPB, TG) and 2 genes frequently mutated in cancer (KRAS and BRAF). The expression tests were intentionally interpreted in a non-quantitative way, i.e. classified tumors either as positive or negative expressors. While applying these tests to 135 cancers belonging to 8 common types of adenocarcinomas (AdCa), we observed that this panel was capable to clearly discriminate between gastrointestinal vs. female reproductive tract vs. lung vs. thyroid tumors in 112 (83%) of cases and provided suggestive clues to correct diagnosis in 20 (15%) of instances. We further assessed the performance of this panel, coupled with the occasional use of 2 additional mutation tests (somatic: EGFR; germ-line: BRCA1), in the real diagnostic setting. The PCR analysis of 20 consecutive CUP with known IHC status turned out to be clinically useful in 19 (95%) cases, with 16 (80%) instances of resolving the existing controversy and 3 (15%) cases of providing valuable confirmation to suspected diagnosis. PCR testing of 20 consecutive CUP with unknown IHC status succeeded to establish tumor organ/tissue origin in 15 (75%) instances and provided suggestive clues to the diagnosis in 3 (15%) patients. We conclude that simple non-expensive laboratory-developed PCR assays may aid CUP diagnosis in a significant proportion of cases.

Various types of cancer, including melanoma and non-melanoma skin cancer, are associated with vitamin D receptor (VDR) polymorphisms. However, few studies have addressed VDR polymorphisms in patients with mycosis fungoides (MF), and previous studies have reported conflicting results. Aim of this case-control study was to assess the correlation between VDR single nucleotide polymorphisms (SNPs) Cdx2, Fok1, Apa1, Bsm1, and Taq1 and MF. Venous blood samples were collected from 41 patients with MF and 59 age- and sex-matched healthy controls. VDR genotypes of both groups were analyzed. Serum vitamin D levels of patients with MF were also analysed among varying stages and VDR genotypes. Vitamin D levels were significantly low (<30 ng/mL) in 87.9% of the patients (P<0.001). No associations were found between Apa1, Cdx2, Fok1, and Bsm1 SNPs and MF. However, Taq1 polymorphisms were higher in the healthy control group (P<0.001). Our study supports the claim that vitamin D deficiency is common in patients with MF. On the other hand, our findings suggest that Taq1 polymorphisms may be associated with decreased susceptibility to MF. Therefore, VDRs may have complex and heterogeneous effects on the pathogenesis of MF.

Loss of CDX2 expression has been proposed to be a prognostic biomarker in colorectal cancer (CRC) correlating with shorter overall (OS) and progression-free survival (PFS). Since metastatic disease, mismatch repair (MMR) deficiency, and the mutational status of BRAF are considered to be important prognostic determinants in CRC, the present study aimed to analyze CDX2 expression in correlation with these parameters. Immunohistochemistry for CDX2, hMLH1, and hMSH2 was applied to a study cohort of 503 CRC specimens (FIRE-3) and a matched case-control collection of 50 right-sided CRC specimens with synchronous distant metastases and 50 right-sided CRCs without distant metastases. Furthermore, the mutational status of BRAF gene was analyzed utilizing pyrosequencing. CDX2 expression significantly correlates with reduced OS (p = 0.008) within the study population. In both cohorts, a significant correlation of CDX2 expression and MMR deficiency as well as the presence of a BRAF mutation (each p > 0.001) was observed, whereas no correlation of CDX2 expression and synchronous metastasis could be obtained. In the case-control study, only patients with proficient MMR status showed a correlation of CDX2 loss and synchronous metastasis, whereas in patients with deficient MMR status and CDX2 loss, no distant metastases at the time of diagnosis were found (p = 0.003). We could demonstrate that the reduced OS of CDX2-negative CRC patients is not caused by higher rates of distant metastases. Furthermore, our data indicate that the prognostic impact of CDX2 depends on the MMR status and the BRAF mutational status of the tumors. Thus, it could be concluded that CDX2 is not an independent prognostic biomarker in CRC.

Several tumor suppressors possess gene regulatory activity. Here, we describe how promoter and promoter/enhancer reporter assays can be used to characterize a colorectal tumor suppressor proteins' gene regulatory activity of possible target genes. In the first part, a bioinformatic approach to identify relevant gene regulatory regions of potential target genes is presented. In the second part, it is demonstrated how to prepare and carry out the functional assay.We explain how to clone the bioinformatically identified gene regulatory regions into luciferase reporter plasmids by the use of the quick and efficient In-Fusion cloning method, and how to carry out transient transfections of Caco-2 colon cancer cells with the produced luciferase reporter plasmids using polyethyleneimine (PEI). A plan describing how to set up and carry out the luciferase expression assay is presented. The luciferase/β-galactosidase (Dual Light) assay presented is a highly sensitive assay that can monitor small changes in the promoter/enhancer activity and includes an internal control monitoring transfection efficiency.

BACKGROUND: Primary pulmonary enteric adenocarcinoma (PEAC) is an extremely rare variant of invasive lung cancer. It is highly heterogeneous while shares some common morphologic and immunohistochemical features with usual pulmonary adenocarcinoma (PAC) and colorectal adenocarcinoma (CRAC), making the differential diagnosis difficult. At present there are only limited studies about distinctive features of primary PEAC and the results are often inconsistent.
METHODS: We retrospectively analyzed total 129 primary PEACs and 50 CRACs that were published since 1991 or diagnosed in our centre. Among them eight typical samples of primary PEACs and usual PACs were detected by targeted exome sequencing.
RESULTS: The combination of CK7
CONCLUSIONS: The combination of CK7

CDX2 is a homeobox gene encoding transcriptional factors for intestinal organogenesis and represents a specific marker of colorectal adenocarcinoma (CRC) differentiation. We have evaluated if CDX2 expression is associated with better overall and disease-free survival (OS and DFS) in patients with CRC. PubMed, SCOPUS, EMBASE, The Cochrane Library, and Web of Science (from inception to July 2017) were systematically reviewed for relevant studies on adult patients with CRC where OS and DFS were calculated according to CDX2 expression in uni- or multivariate analysis were included. Hazard ratio (HR) for mortality and/or disease progression was calculated. The search produced 16 studies suitable for inclusion (6291 individual patients). The meta-analysis showed a reduced risk of death for patients with CDX2-positive CRC in 14 studies (HR, 0.5; 95% confidence interval [CI], 0.38-0.66; P < .001 according to random effect model). In 6 studies where only DFS data was available, CDX2 expression led to a 52% lower risk of relapse or death (HR, 0.48; 95% CI, 0.39-0.59; P < .001 according to random effect model). The results did not change as a function of ethnicity, type of study, CDX2 detection modality, or stage. Interestingly, in stages II to III, CDX2 expression was associated with a 70% lower risk of death (HR, 0.3; 95% CI, 0.12-0.77; P = .01). CDX2 expression confirms to be a strong prognostic factor in stage II and III CRC. In this setting, along with other clinical and pathologic factors, the lack of expression of CDX2 may be considered an important variable when deciding for adjuvant chemotherapy.

Developmental genes contribute to cancer, as reported for the homeobox gene

Strong prognostic markers able to stratify lung adenocarcinoma (ADC) patients are lacking. We evaluated whether a six-immunohistochemical markers panel (TTF1, SP-A, Napsin A, MUC5AC, CDX2 and CK5), defining the putative neoplastic "cell of origin," allows to identify prognostic subgroups among lung ADC. We screened a large cohort of ADC specimens (2003-2013) from Torino Institutional Repository identifying: (i) marker positivity by immunohistochemistry, (ii) main morphological appearance by light microscopy, (iii) presence of "hotspot" mutations of candidate genes by Sequenom technology. To evaluate possible predictors of survival and time to recurrence, uni- and multivariable-adjusted comparisons were performed. We identified 4 different subgroups: "alveolar," "bronchiolar," "mixed" and "null type." Alveolar-differentiated ADC were more common in young (P=.065), female (P=.083) patients, frequently harboring EGFR-mutated (P=.003) tumors with acinar pattern (P<.001). Bronchiolar-differentiated ADC were more associated with mucinous and solid pattern (P<.001), higher degree of vascular invasion (P=.01) and KRAS gene mutations (P=.07). Bronchiolar, mixed, and null types were independent negative predictors for overall survival, and the latter two had a shorter time to recurrence. This "Cell of Origin" classifier is more predictable than morphology and genetics and is an independent predictor of survival on a multivariate analysis.

Oncogenic mutations in BRAF are believed to initiate serrated colorectal cancers; however, the mechanisms of BRAF-driven colon cancer are unclear. We find that oncogenic BRAF paradoxically suppresses stem cell renewal and instead promotes differentiation. Correspondingly, tumor formation is inefficient in BRAF-driven mouse models of colon cancer. By reducing levels of differentiation via genetic manipulation of either of two distinct differentiation-promoting factors (Smad4 or Cdx2), stem cell activity is restored in BRAF

CLINICAL PRESENTATION: A 77-year-old man presented to our skin cancer centre with various cutaneous tumours occurring in 2006-2017. Histopathology showed a 'hidradenocarcinoma' on the left upper back (2006) and a sebaceous adenoma (figure 1) on the left shoulder (2011). In 2017, he developed a sebaceous carcinoma on the middle upper back, which manifested as a slowly enlarging, asymptomatic nodule. Medical history was significant for curative resection of colorectal cancer in 1988.gutjnl;67/11/1957/F1F1F1Figure 1Clinical appearance of the sebaceous adenoma on the patient's left shoulder in 2011.The most recent lesion was subjected to extensive immunohistochemical assessment. The neoplastic cells were positive for cytokeratin 5/6, cytokeratin 7, cluster of differentiation antigen 10, adipophilin, androgen receptor, epithelial membrane antigen, KI67 antigen, MLH1 and PMS2, but stained negative for gross cystic disease fluid protein 15, prostate-specific antigen, carbohydrate antigen 19/9, CDX2 protein, hepatocyte-specific antigen, carcinoembryonic antigen, cluster of differentiation antigen 117 and cytokeratin 19. Given the variety of histological manifestations of the patient's skin neoplasms, further studies were performed. They revealed positive nuclear expression signals for MLH1, MSH6 and PMS2, whereas MSH2 expression was absent in almost all tumour cells (figure 2). Positron emission tomography (PET)/CT and colonoscopy did not detect any pathological findings. However, molecular genetic analysis of peripheral blood showed a heterozygous deletion of exon 7 of the
QUESTION: What is your diagnosis?
DIAGNOSIS: Muir-Torre syndrome (MTS).

BACKGROUND AND STUDY AIM: Colorectal cancer (CRC) is a heterogeneous disease entity with a diverse biological pathogenesis. This study aims to validate the two studies published in 2013 which established a separate CRC molecular subtype classification by utilizing a rapidly accessible miniclassifier, and verify a simplified version thereof.
PATIENTS AND METHODS: Participants diagnosed with CRC (n = 568) were subtyped in three classifications for characteristic, and prognostic purposes. Colorectal cancer subtypes (CCS) were classified as: i) CCS1 (CDX2+, microsatellite stable (MSS)/microsatellite instability (MSI)-low), ii) CCS2 (MSI-high), and iii) CCS3 (FRMD6/ZEB1/HTR2B +, CDX2-, MSS/MSI-low]. Simplified CCS (SiCCS) subtypes were grouped as: i) CDX2 (CDX2+, MSS/MSI-low, ZEB1 ≤ 2), ii) MSI-H (MSI-high, CDX2/FRMD6/ZEB1/HTR2B +/-), and iii) ZEB1 (ZEB1 ≥ 2, CDX2-, MSS/MSI-low). New molecular classification (NMC) subtypes were defined as: i) enterocyte (E-C) (MUC2 +), ii) goblet-like (G-L) (MUC2 + and TFF3 +), iii) transit-amplifying (T-A) (CFTR +), and iv) stem-like (S-L) (ZEB1 +).
RESULTS: In total, 53.5% (n = 304) CCS, 58.3% (n = 331) SiCCS, and 37.7% (n = 214) NMC tumours could be evaluated. CCS2 and MSI-H CRCs had the most favourable survival outcome, whereas the CCS3, ZEB1 and S-L subtypes showed the poorest prognosis. A significant overlap between CCS3, ZEB1, and S-L tumours was demonstrated.
CONCLUSION: There is still a need for a consensus gene expression-based subtyping classification system for CRCs, thereby allowing the categorization of most CRC tumours. This study reveals that a simple and rapidly accessible process could replace the complicated, costly and mostly inapproachable methods clinical practices that have been introduced in the majority of previous studies.

Dysregulation of microRNAs (miRNAs) has been linked to virulence factors of Helicobacter pylori. The role of H. pylori in esophageal disease has not been clearly defined. We previously reported that H. pylori esophageal colonization promotes the incidence of Barrett's esophagus and esophageal adenocarcinoma in vivo. Here, we studied the direct effects of H. pylori on the transformation of esophageal epithelial cells, with particular focus on whether H. pylori exerts its effects by modulating miRNAs and their downstream target genes. The normal human esophageal cell line HET-1A was chronically exposed to H. pylori extract and/or acidified deoxycholic acid for up to 36 weeks. The miRNA profiles of the esophageal epithelial cells associated with H. pylori infection were determined by microarray analysis. We found that chronic H. pylori exposure promoted acidified deoxycholic acid-induced morphological changes in HET-1A cells, along with aberrant overexpression of intestinal metaplasia markers and tumorigenic factors, including caudal-type homeobox protein 2 (CDX2), mucin 2, and cyclooxygenase 2 (COX2). Helicobacter pylori modified the miRNA profiles of esophageal epithelial cells, particularly aberrant silencing of miR-212-3p and miR-361-3p. Moreover, in biopsies from Barrett's esophagus patients, esophageal H. pylori colonization was associated with a significant decrease in miR-212-3p and miR-361-3p expression. Furthermore, we identified COX2 as a target of miR-212-3p, and CDX2 as a target of miR-361-3p. Helicobacter pylori infection of esophageal epithelial cells was associated with miRNA-mediated upregulation of oncoprotein CDX2 and COX2. Our observations provide new evidence about the molecular mechanisms underlying the association between H. pylori infection and esophageal carcinogenesis.

Phenotypic conversion of tumor cells through epithelial-mesenchymal transition (EMT) requires massive gene expression changes. How these are brought about is not clear. Here we examined the impact of the EMT master regulator SNAIL1 on the FOXA family of transcription factors which are distinguished by their particular competence to induce chromatin reorganization for the activation of transcriptional enhancer elements. We show that the expression of SNAIL1 and FOXA genes is anticorrelated in transcriptomes of colorectal tumors and cell lines. In cellular EMT models, ectopically expressed Snail1 directly represses FOXA1 and triggers downregulation of all FOXA family members, suggesting that loss of FOXA expression promotes EMT. Indeed, cells with CRISPR/Cas9-induced FOXA-deficiency acquire mesenchymal characteristics. Furthermore, ChIP-seq data analysis of FOXA chromosomal distribution in relation to chromatin structural features which characterize distinct states of transcriptional activity, revealed preferential localization of FOXA factors to transcriptional enhancers at signature genes that distinguish epithelial from mesenchymal colon tumors. To validate the significance of this association, we investigated the impact of FOXA factors on structure and function of enhancers at the CDH1, CDX2 and EPHB3 genes. FOXA-deficiency and expression of dominant negative FOXA2 led to chromatin condensation at these enhancer elements. Site-directed mutagenesis of FOXA binding sites in reporter gene constructs and by genome-editing in situ impaired enhancer activity and completely abolished the active chromatin state of the EPHB3 enhancer. Conversely, expression of FOXA factors in cells with inactive CDX2 and EPHB3 enhancers led to chromatin opening and de novo deposition of the H3K4me1 and H3K27ac marks. These findings establish the pioneer function of FOXA factors at enhancer regions of epithelial genes and demonstrate their essential role in maintaining enhancer structure and function. Thus, by repressing FOXA family members, SNAIL1 targets transcription factors at strategically important positions in gene-regulatory hierarchies, which may facilitate transcriptional reprogramming during EMT.

The purpose of this systemic review and meta-analysis was to examine the relationship between VDR gene polymorphisms and breast cancer. Literature was searched through PubMed database, Google scholar, and the web of knowledge from December 2015 to January 2017 and consists of 34 studies (26,372 cases and 32,883 controls). All statistical measures were done using STATA version 11.2. The heterogeneity among studies was tested using I

Gastric carcinogenesis has been associated to H. pylori virulence factors that induce a chronic inflammation process. Lipopolysaccharides play a role in chronic inflammatory responses via TLR2- and TLR4-dependent signaling pathways. Similarly, cellular invasiveness, metastatic potential and prognosis are usually associated to claudin-4, -6, -7 and -9 expression in gastric carcinogenesis. Therefore, the aim of this study was to determine if H. pylori LPS exerts an influence on carcinogenesis-related claudin expression and if it was directly regulated through the TLR2 pathway. Human antrum gastric adenocarcinoma AGS cells exposed or not to H. pylori LPS were used. Polyclonal anti-claudin-4, -6, -7 and -9, anti-TLR2, anti-pERK1/2 as well as rabbit monoclonal anti-pNFκB p65 and mouse monoclonal anti-CdX2 were used. ERK1/2 inhibitor UO126 and STAT3 inhibitor Stattic were also used. Western blot, immunofluorescence and confocal experiments were performed in whole cells as well as total protein, nuclear and cell membrane fractions. The results showed that H. pylori LPS increased the expression of TLR2 in a time dependent bi-phasic manner (<12 and >12h exposure). Immunofluorescence using AGS monolayers corroborated the double phase TLR2 expression mainly on the cell membrane but a detectable signal was also determined in the cytoplasm of the cells. Activation of NFkB was downstream and depended on TLR2 expression as a statistically significant increase in pNFkB, that followed a pattern highly similar to the TLR2 expression was observed on the cell membrane fraction. The increase in TLR2 expression was accompanied by dramatically increased claudin-4 expression in cultures exposed from 30m to 8h to LPS. Increased expression of claudin-6, -7 and -9 also increases in >12h LPS exposure times. The increase in claudins expression was also dependent on NFkB activation. The results also showed an increase in pSTAT3 that followed a bi-phasic pattern that began 30min after stimulation and was compatible with the increase in TLR2 expression. The expression of the claudin-4 related CDX2 transcription factor did not followed the biphasic pattern. The results also showed that claudin-4 expression was STAT3 dependent whereas claudin-6, 7 and 9 expressions was ERK1/2 dependent. Our results suggest that H. pylori LPS induces TLR2 expression in the AGS cells, and that the longer the exposure to LPS, the greater the expression of TLR2 in the cell membrane. Consequently the expression of claudin-4, -6, -7 and -9 also increases.