Loss of GLTSCR1 causes congenital heart defects by regulating NPPA transcription.

Precise and specific spatiotemporal domains of gene expression regulation are critical for embryonic development. Recent studies have identified GLTSCR1 as a gene transcriptional elongation regulator in cancer research. However, the function of GLTSCR1, especially in embryonic development, remains poorly understood. Here, we found that GLTSCR1 was essential for cardiac development because Gltscr1 knockout (Gltscr1-/-) led to embryonic lethality in mice with severe congenital heart defects (CHDs). Ventricular septal defect and double outflow right ventricular were also observed in neural crest cells with conditional deletion of Gltscr1, which were associated with neonatal lethality in mice. Mechanistically, GLTSCR1 deletion promoted NPPA expression by coordinating the CHD risk G allele of rs56153133 in the NPPA enhancer and releasing the transcription factor ZNF740-binding site on the NPPA promoter. These findings demonstrated that GLTSCR1 acts as a candidate CHD-related gene.

In Vivo Staging the Progression of Colitis and Associated Cancer by Concurrent Microimaging of Key Biomarkers.

Currently colorectal cancer (CRC) staging (colitis, adenoma, and carcinoma) mainly relies on ex vivo pathologic analysis requiring an invasive surgical process with limited sample collection and increased metastatic risk. Thus, in vivo noninvasive pathological diagnosis is extremely demanded. By verifying the samples of clinical patients and CRC mouse models, it was found that vascular endothelial growth factor receptor 2 (VEGFR2) was barely expressed in the colitis stage and only appeared in adenoma and carcinoma stages with obvious elevation, while prostaglandin E receptor 4 (PTGER4) could be observed from colitis to adenoma and carcinoma stages with a gradient increase of expression. VEGFR2 and PTGER4 were further chosen as key biomarkers for molecular pathological diagnosis in vivo and corresponding molecular probes were constructed. The feasibility of in vivo noninvasive CRC staging by concurrent microimaging of dual biomarkers using confocal laser endoscopy (CLE) was verified in CRC mouse models and further confirmed by ex vivo pathological analysis. In vivo CLE imaging exhibited the correlation of severe colonic crypt structural alteration with a higher biomarker expression in adenoma and carcinoma stages. This strategy shows promise in benefiting patients undergoing CRC progression with in-time, noninvasive, and precise pathological staging, thus providing valuable guidance for selecting therapeutic strategies.

The expression of ADAMTS14 is regulated by promoter DNA methylation and is associated with poor prognosis in colorectal cancer.

Colorectal cancer (CRC) is one of the most common malignant tumors of digestive system, and its main cause of death is tumor metastasis. The occurrence of CRC is a polygenic and multi-step complex process involving genetic and epigenetic alterations. It has been demonstrated that ADAMTS14 (A disintegrin and metalloproteinase with thrombospondin motifs 14) was hypermethylated in esophageal cancer using whole-genome methylation microarray in our previous report. The present study revealed that ADAMTS14 was highly methylated accompanied with low expression in CRC. In addition, demethylation agent 5-Aza-dC could demethylate ADAMTS14 promoter region and reactivate ADAMTS14 expression effectively in vitro. Therefore, promoter hypermethylation was probably contributed to ADAMTS14 epigenetic silencing in CRC. Furthermore, ADAMTS14 protein expression was higher at invasive tumor front than at the tumor center or other areas of tumor. Kaplan-meier survival analysis indicated that the high ADAMTS14 expression was correlated with poor prognosis in CRC patients, suggesting the possibility that ADAMTS14 is a promising indicator in the evaluation of CRC prognosis.

p38-regulated FOXC1 stability is required for colorectal cancer metastasis.

Aberrant expression of forkhead box C1 (FOXC1) promotes tumor metastasis in multiple human malignant tumors. However, the upstream modulating mode and downstream molecular mechanism of FOXC1 in metastasis of colorectal cancer (CRC) remain unclear. Herein we describe a systematic analysis of FOXC1 expression and prognosis in CRC performed on our clinical data and public databases, which indicated that FOXC1 upregulation in CRC samples was significantly associated with poor prognosis. FOXC1 knockdown inhibited migration and invasion, whereas FOXC1 overexpression caused the opposite phenotype in vitro and in vivo. Furthermore, MMP10, SOX4 and SOX13 were verified as the target genes of FOXC1 for promoting CRC metastasis. MMP10 was demonstrated as the direct target and mediator of FOXC1. Interestingly, Ser241 and Ser272 of FOXC1 were identified as the key sites to interact with p38 and phosphorylation, which were critically required for maintaining the stability of FOXC1 protein. Moreover, FOXC1 was dephosphorylated by protein phosphatase 2A and phosphorylated by p38, which maintained FOXC1 protein stability through inhibiting ubiquitination. Expression of p38 was correlated with FOXC1 and MMP10 expression, indirectly indicating that FOXC1 was regulated by p38 MAPK. Therefore, FOXC1 is strongly suggested as a pro-metastatic gene in CRC by transcriptionally activating MMP10, SOX4 and SOX13; p38 interacts with and phosphorylates the Ser241 and ser272 sites of FOXC1 to maintain its stability by inhibiting ubiquitination and degradation. In conclusion, the protein stability of FOXC1 mediated by p38 contributes to the metastatic effect in CRC. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Research progress on application of microhaplotype in forensic genetics.

As a novel genetic marker, microhaplotype can be applied in the field of forensic genetics. Microhaplotype has the advantages of high polymorphism, low mutation rate, no stutter products and short amplification fragments. Microhaplotype can effectively detect mixture, and quantitatively analyze the contributors of mixture. DNA with severe fragmentation can be successfully genotyped by microhaplotype. It can be used as ancestry informative marker to effectively divide the global continental population according to genetic structure. Microhaplotype system can provide more information than traditional short tandem repeat and help to identify complex relationships. It can provide new ideas for tumor source identification, cell line identification and prenatal paternity testing. Here we review the applications of microhaplotype, intending to provide references for forensic practice.

SRSF6-regulated alternative splicing that promotes tumour progression offers a therapy target for colorectal cancer.

OBJECTIVE: To investigate the molecular function of splicing factor SRSF6 in colorectal cancer (CRC) progression and discover candidate chemicals for cancer therapy through targeting SRSF6. DESIGN: We performed comprehensive analysis for the expression of SRSF6 in 311 CRC samples, The Cancer Genome Atlas and Gene Expression Omnibus (GEO) database. Functional analysis of SRSF6 in CRC was performed in vitro and in vivo. SRSF6-regulated alternative splicing (AS) and its binding motif were identified by next-generation RNA-sequencing and RNA immunoprecipitation sequencing (RIP-seq), which was validated by gel shift and minigene reporter assay. ZO-1 exon23 AS was investigated to mediate the function of SRSF6 in vitro and in vivo. Based on the analysis of domain-specific role, SRSF6-targeted inhibitor was discovered de novoby virtual screening in 4855 FDA-approved drugs and its antitumour effects were evaluated in vitroand in vivo. RESULTS: SRSF6 was frequently upregulated in CRC samples and associated with poor prognosis, which promoted proliferation and metastasis in vitro and in vivo. We identified SRSF6-regulated AS targets and discovered the SRSF6 binding motif. Particularly, SRSF6 regulates ZO-1 aberrant splicing to function as an oncogene by binding directly to its motif in the exon23. Based on the result that SRSF6 RRM2 domain plays key roles in regulating AS and biological function, indacaterol, a ß2-adrenergic receptor agonist approved for chronic obstructive pulmonary disease treatment, is identified as the inhibitor of SRSF6 to suppress CRC tumourigenicity. CONCLUSIONS: SRSF6 functions the important roles in mediating CRC progression through regulating AS, and indacaterol is repositioned as an antitumour drug through targeting SRSF6. ACCESSION NUMBERS: The accession numbers for sequencing data are SRP111763 and SRP111797.

Mutations of key driver genes in colorectal cancer progression and metastasis.

The association between mutations of key driver genes and colorectal cancer (CRC) metastasis has been investigated by many studies. However, the results of these studies have been contradictory. Here, we perform a comprehensive analysis to screen key driver genes from the TCGA database and validate the roles of these mutations in CRC metastasis. Using bioinformatics analysis, we identified six key driver genes, namely APC, KRAS, BRAF, PIK3CA, SMAD4 and p53. Through a systematic search, 120 articles published by November 30, 2017, were included, which all showed roles for these gene mutations in CRC metastasis. A meta-analysis showed that KRAS mutations (combined OR 1.18, 95% CI 1.05-1.33) and p53 mutations (combined OR 1.49, 95% CI 1.23-1.80) were associated with CRC metastasis, including lymphatic and distant metastases. Moreover, CRC patients with a KRAS mutation (combined OR 1.29, 95% CI 1.13-1.47), p53 mutation (combined OR 1.35, 95% CI 1.06-1.72) or SMAD4 mutation (combined OR 2.04, 95% CI 1.41-2.95) were at a higher risk of distant metastasis. Subgroup analysis stratified by ethnic populations indicated that the BRAF mutation was related to CRC metastasis (combined OR 1.42, 95% CI 1.18-1.71) and distant metastasis (combined OR 1.51, 95% CI 1.20-1.91) in an Asian population. No significant association was found between mutations of APC or PIK3CA and CRC metastasis. In conclusion, mutations of KRAS, p53, SMAD4 and BRAF play significant roles in CRC metastasis and may be both potential biomarkers of CRC metastasis as well as therapeutic targets.

The long non-coding RNA CYTOR drives colorectal cancer progression by interacting with NCL and Sam68.

BACKGROUND: Long non-coding RNAs (lncRNAs) function as key molecules in cancer progression. The lncRNA CYTOR plays oncogenic roles in multiple types of cancer, yet the detailed molecular mechanisms of those roles remain unknown. The aim of this study was to investigate the clinical significance, biological function and interacting partners of CYTOR in colorectal cancer (CRC). METHODS: A systematic and comprehensive analysis of CYTOR expression was performed in 138 CRC samples and in the TCGA and GEO databases. Biological function was investigated through knockdown and overexpression of CYTOR in vitro and in vivo. In addition, its protein binding partner was identified and validated using ChIRP-MS and RNA immunoprecipitation assays. Their key interaction sites on CYTOR were verified by CRISPR/Cas9 and a series of mutant constructs. Furthermore, the downstream targets of CYTOR were confirmed via immunoblotting and luciferase reporter assays. RESULTS: CYTOR was significantly up-regulated in CRC samples and associated with poor prognosis, promoting proliferation and metastasis in vitro and in vivo. NCL and Sam68 could recognize their specific motifs and directly bind to EXON1 of CYTOR. Moreover, EXON1 was the key functional site mediating the interaction of CYTOR with NCL and Sam68. NCL and Sam68 functioned as oncogenes to promote CRC progression. Furthermore, we confirmed that the heterotrimeric complex of CYTOR, NCL and Sam68 activated the NF-κB pathway and EMT to contribute to CRC progression. CONCLUSION: CYTOR plays important roles in CRC progression by interacting with NCL and Sam68 and may serve as a prognostic biomarker and/or an effective target for CRC therapies.

HOTAIRM1 as a potential biomarker for diagnosis of colorectal cancer functions the role in the tumour suppressor.

Recent studies have revealed many different long noncoding RNAs (lncRNA), however, the investigation for their function and clinical value as tumour biomarkers has scarcely begun. Here, we found that expression of HOTAIRM1 was reduced in colorectal cancer (CRC) tissues compared with matched normal tissues, and plasma HOTAIRM1 levels in CRC patients were less than in controls. The cut-off point was chosen as 0.003 with a sensitivity of 64.00% and a specificity of 76.50% in the validation set. The performance of HOTAIRM1 was highly comparable to carcinoembryonic antigen (CEA), and better than CA19-9 and CA125. The combined assay of HOTAIRM1 and CEA raised the sensitivity and specificity to 84.00%. HOTAIRM1 knockdown resulted in obvious changes in expression of the cell proliferation related to genes and promoted cell proliferation. HOTAIRM1 plays a role of tumour suppressor in CRC; Down-regulation of HOTAIRM1 can serve as a biomarker for CRC, and combined HOTAIRM1 and CEA assay might provide a promising diagnosis for CRC.

Growth differentiation factor 15 is a promising diagnostic and prognostic biomarker in colorectal cancer.

Although various studies have demonstrated that growth differentiation factor 15 (GDF15) might be a potential diagnostic and prognostic marker in colorectal cancer (CRC) patients, the results are inconsistent and the statistical power of individual studies is also insufficient. An original study was conducted to explore the diagnostic and prognostic value of serum GDF15 in CRC patients. We also conducted a meta-analysis study which aimed to summarize the diagnostic and prognostic performance of serum GDF15 in CRC. We searched PubMed and ISI Web of Knowledge up to 1 November 2014 for eligible studies. In order to explore the diagnostic performance of GDF15, standardized mean difference (SMD) and their 95% confidence intervals (CI) were estimated and receiver-operating characteristic (ROC) curves were constructed. For prognostic meta-analysis, study-specific hazard ratios (HRs) of serum GDF15 for survival were summarized. A total of eight studies were included in the meta-analyses. Our results revealed that serum GDF15 levels in CRC patients were higher than those in healthy controls (SMD = 1.08, 95% CI: 0.56-1.59, P < 0.001). For discriminating CRC from healthy controls, the AUC of GDF15 was 0.816 (95% CI: 0.792-0.838). The sensitivity and specificity were 58.9% (95% CI: 55.0-62.8) and 92.08% (95% CI: 89.2-94.4), respectively, when a cut-off value of 1099 pg/ml was established. Besides, higher GDF15 expression level was associated with worse overall survival for CRC patients (pooled HR = 2.09, 95% CI: 1.47-2.96). In conclusion, the present meta-analysis suggests that serum GDF15 may be a useful diagnostic and prognostic biomarker for CRC.

[Association of neuroendocrine differentiation with progression and prognosis of gastric adenocarcinoma].

OBJECTIVE: To investigate the association of neuroendocrine differentiation with progression and prognosis of gastric adenocarcinoma. METHODS: Clinicopathological data of 240 patients with gastric adenocarcinomas were retrospectively analyzed. The expression of chromogranin A, synaptophysin and secrectagogin in cancer tissue was assessed by immunohistochemistry. The association of neuoroendocrine differentiation parameters with disease progression and survival of patients was analyzed. RESULTS: The expression of synaptophysin was positively correlated with depth of invasion and secretagogin more often expressed in cases with lymph node metastasis. In Lauren diffuse type of cancer, expression of chromogranin A and secretagogin was unfavorable prognostic predictor. In TNM stage II adenocarcinoma, expression of chromogranin A and synaptophysin related to poor survival, and multivariate Cox proportional hazard model showed that synaptophysin was an independent predictor for poor survival. CONCLUSION: Neuroendocrine differentiation predicts deeper depth of invasion, more possibility of lymph node metastasis and poor survival in gastric adenocarcinoma.

Genetic variants in the fibroblast growth factor pathway as potential markers of ovarian cancer risk, therapeutic response, and clinical outcome.

BACKGROUND: The fibroblast growth factor (FGF) and FGF receptor (FGFR) axis plays a critical role in tumorigenesis, but little is known of its influence in ovarian cancer. We sought to determine the association of genetic variants in the FGF pathway with risk, therapeutic response, and survival of patients with ovarian cancer. METHODS: We matched 339 non-Hispanic white ovarian cancer cases with 349 healthy controls and genotyped them for 183 single-nucleotide polymorphisms (SNPs) from 24 FGF (fibroblast growth factor) and FGFR (fibroblast growth factor receptor) genes. Genetic associations for the main effect, gene-gene interactions, and the cumulative effect were determined. RESULTS: Multiple SNPs in the FGF-FGFR axis were associated with an increased risk of ovarian cancer. In particular, FGF1 [fibroblast growth factor 1 (acidic)] SNP rs7727832 showed the most significant association with ovarian cancer (odds ratio, 2.27; 95% CI, 1.31-3.95). Ten SNPs were associated with a reduced risk of ovarian cancer. FGF18 (fibroblast growth factor 18) SNP rs3806929, FGF7 (fibroblast growth factor 7) SNP rs9920722, FGF23 (fibroblast growth factor 23) SNP rs12812339, and FGF5 (fibroblast growth factor 5) SNP rs3733336 were significantly associated with a favorable treatment response, with a reduction of risk of nonresponse of 40% to 60%. Eleven SNPs were significantly associated with overall survival. Of these SNPs, FGF23 rs7961824 was the most significantly associated with improved prognosis (hazard ratio, 0.55; 95% CI, 0.39-0.78) and was associated with significantly longer survival durations, compared with individuals with the common genotype at this locus (58.1 months vs. 38.0 months, P = 0.005). Survival tree analysis revealed FGF2 rs167428 as the primary factor contributing to overall survival. CONCLUSIONS: Significant associations of genetic variants in the FGF pathway were associated with ovarian cancer risk, therapeutic response, and survival. The discovery of multiple SNPs in the FGF-FGFR pathway provides a molecular approach for risk assessment, monitoring therapeutic response, and prognosis.

Association of mitochondrial DNA copy number in peripheral blood leukocytes with risk of esophageal adenocarcinoma.

Alterations of mitochondrial DNA (mtDNA) have been associated with the risk of a number of human cancers; however, the relationship between mtDNA copy number in peripheral blood leukocytes and the risk of esophageal adenocarcinoma (EAC) has not been reported. In this study, we determined relative mtDNA copy number in peripheral blood leukocytes of 218 EAC cases and 218 frequency-matched controls. We calculated odds ratios and 95% confidence intervals using unconditional logistic regression, adjusting for age, sex and smoking status. MtDNA copy number was significantly lower in cases than in controls (mean ± SD, 1.16 ± 0.30 versus 1.27 ± 0.43, P = 0.002). Dichotomized at the median value of mtDNA copy number in the controls, low mtDNA copy number was significantly associated with an increased risk of EAC (odds ratio: 1.55, 95% confidence interval: 1.05-2.29). A significant dose-response relationship was observed between mtDNA copy number and risk of EAC in quartile analysis. Our results suggest that low mtDNA copy number in peripheral blood leukocytes is associated with increased susceptibility to EAC.

Genome-wide methylation analysis shows similar patterns in Barrett's esophagus and esophageal adenocarcinoma.

Barrett's esophagus (BE) is a precursor of esophageal adenocarcinoma (EAC). To identify novel tumor suppressors involved in esophageal carcinogenesis and potential biomarkers for the malignant progression of BE, we performed a genome-wide methylation profiling of BE and EAC tissues. Using Illumina's Infinium HumanMethylation27 BeadChip microarray, we examined the methylation status of 27 578 CpG sites in 94 normal esophageal (NE), 77 BE and 117 EAC tissue samples. The overall methylation of CpG sites within the CpG islands was higher, but outside of the CpG islands was lower in BE and EAC tissues than in NE tissues. Hierarchical clustering analysis showed an excellent separation of NE tissues from BE and EAC tissues; however, the clustering of BE and EAC tissues was less clear, suggesting that methylation occurs early during the progression of EAC. We confirmed many previously reported hypermethylated genes and identified a large number of novel hypermethylated genes in BE and EAC tissues, particularly genes encoding ADAM (A Disintegrin And Metalloproteinase) peptidase proteins, cadherins and protocadherins, and potassium voltage-gated channels. Pathway analysis showed that a number of channel and transporter activities were enriched for hypermethylated genes. We used pyrosequencing to validate selected candidate genes and found high correlations between the array and pyrosequencing data (rho > 0.8 for each validated gene). The differentially methylated genes and pathways may provide biological insights into the development and progression of BE and become potential biomarkers for the prediction and early detection of EAC.

Short telomere lengths in peripheral blood leukocytes are associated with an increased risk of oral premalignant lesion and oral squamous cell carcinoma.

BACKGROUND: Oral premalignant lesions (OPLs) are precursors of oral squamous cell carcinoma (OSCC). Short telomeres in peripheral blood leukocytes (PBLs) are associated with increased risks of several cancers. However, it is unclear whether short leukocyte telomere length (LTL) predisposes individuals to OPL and OSCC. METHODS: LTL was measured in PBLs from 266 patients who had a diagnosis of either OPL (N = 174) or OSCC (N = 92) and from 394 age-matched and sex-matched controls. The association between LTL and the risk of OPL or OSCC, as well as the interaction of telomere length, cigarette smoking, and alcohol drinking on the risk of OPL or OSCC, were analyzed. RESULTS: The age-adjusted relative LTL was shortest in the OSCC group (1.64 ± 0.29), intermediate in the OPL group (1.75 ± 0.43), and longest in the control group (1.82 ± 0.36; Ptrend < .001). When the analysis was dichotomized at the median value in controls, adjusting for age, sex, smoking status, and alcohol drinking status, the odds ratio for the risk of OPL and OSCC associated with short LTL was 2.03 (95% confidence interval, 1.29-3.21) and 3.47 (95% CI, 1.84-6.53), respectively, with significant dose-response effects for both associations. Among 174 patients with OPL, 23 progressed to OSCC, and the mean LTL was shorter in progressors than in nonprogressors (mean ± standard deviation: 1.66 ± 0.35 vs 1.77 ± 0.44, respectively), although the difference did not reach statistical significance (P = .258), probably because of the small number of progressors. An interaction analysis identified short LTL, smoking, and drinking alcohol as independent risk factors for OPL and OSCC. CONCLUSIONS: Short LTL was associated with increased risks of developing OPL and OSCC. The current results also indicated that short LTL likely predisposes patients to the malignant progression of OPL.

AMER1 deficiency promotes the distant metastasis of colorectal cancer by inhibiting SLC7A11- and FTL-mediated ferroptosis.

The crosstalk between ferroptosis and cancer metastasis remains unclear. Here, we identify AMER1 as a key regulator of ferroptosis. AMER1 loss causes resistance to ferroptosis in colorectal cancer (CRC) cells. Interestingly, AMER1-deficient CRC cells preferentially form distant metastases, while AMER1-naive CRC cells mainly invade lymph nodes. Moreover, the ferroptosis inhibitor liproxstatin-1 effectively promotes hematogenous transfer of AMER1-naive cells. Mechanistically, AMER1 binds to SLC7A11 and ferritin light chain (FTL) and recruits ß-TrCP1/2, which degrade SLC7A11 and FTL by ubiquitination. Therefore, AMER1 deficiency increases cellular cystine levels but decreases the pool of labile free iron, thereby enhancing resistance to ferroptosis in CRC cells. Thus, AMER1 deficiency increases the survival of CRC cells in the blood under conditions of high oxidative stress and then promotes hematogenous metastasis of CRC. In conclusion, AMER1 mediates the crosstalk between ferroptosis and cancer metastasis, which provides a window of opportunity for treating metastatic colorectal cancer patients with AMER1 mutations.

Twin pregnancy with complete hydatidiform mole and co-existing fetus: A report of 15 cases with a clinicopathological analysis and DNA genotyping.

Complete hydatidiform mole (CHM) with co-existing fetus (CHMCF) is very uncommon. In this study, we investigated the clinicopathological features and DNA genotype in 15 CHMCF. Seven patients (46.7%) developed post-molar gestational trophoblastic disease (GTD), 5 of which had lung metastasis. CHMCF was histologically characterized by a mixed pattern of CHM and the non-molar placenta, mimicking partial hydatidiform mole and placental mesenchymal dysplasia. p57 immunostaining showed a divergent staining pattern, positive in the normal placenta and negative in the CHM component. DNA genotyping of the CHM villi demonstrated exclusively paternal alleles consisting of homozygous/monospermic (n = 9) and heterozygous/dispermic patterns (n = 5) at multiple informative loci. We conclude that CHMCF confers a high risk for post-molar GTD. DNA genotyping contributes significantly to the precision diagnosis of CHMCF.

Independent validation of distinct clinicopathological features and prognosis among usual-type, mucinous-type and gastric-type endocervical adenocarcinoma categorised by new WHO classification (2020).

The new World Health Organization (WHO) classification of tumours of the female genital tract (2020) divides endocervical adenocarcinoma (EAC) into human papilloma virus (HPV)-related adenocarcinoma (HPVA) and HPV-independent adenocarcinoma (HPVI) to underscore the morphological and pathogenetic correlation. It may be potentially prognostic. In this study, we appraised the new WHO classification in an independent, single institution-based EAC cohort from China to assess the clinicopathological features and prognostic value among tumour types. Our study cohort contained 402 consecutive, surgically excised EACs consisting of 298 (74.1%) HPVA, 88 (21.9%) HPVI and 16 (4%) adenocarcinomas not otherwise specified (NOS). Usual-type (55.7%) and gastric-type adenocarcinoma (GAC) (18.2%) was the most common type in HPVA and HPVI, respectively. Block p16 staining (94.7% vs 24.4%) and HPV mRNA signal (89.4% vs 0) were more common in HPVA than in HPVI (p<0.001). HPVI or GAC were more frequently associated with prognostically adverse variables including old age, large tumour size, deep invasion of the cervical wall, high tumour stage, spread of the upper genital tract, lymphovascular invasion, and mutant-type p53 expression, compared to HPVA or mucinous/usual-type HPVA, respectively (all p<0.001). In univariate survival analysis, HPVI had a worse overall survival and higher tumour recurrence compared to HPVA (p<0.05). Mucinous-type HPVA showed a worse prognosis than usual-type HPVA, but better than GAC (p<0.001). Multivariate survival analysis demonstrated that HPVI was independently associated with a worse overall survival and tumour recurrence (p<0.05) while GAC was an adverse prognostic factor independently of FIGO stage (p<0.05). Our findings validate the value of the new WHO classification in prognostic stratification and pathogenetic correlation in EAC and its subtypes.

GLTSCR1 coordinates alternative splicing and transcription elongation of ZO1 to regulate colorectal cancer progression.

Alternative splicing (AS) and transcription elongation are vital biological processes, and their dysregulation causes multiple diseases, including tumors. However, the coregulatory mechanism of AS and transcription elongation in tumors remains unclear. This study demonstrates a novel AS pattern of tight junction protein 1 (ZO1) regulated by the RNA polymerase II elongation rate in colorectal cancer (CRC). Glioma tumor suppressor candidate region gene 1 (GLTSCR1) decreases the transcription elongation rate of ZO1 to provide a time window for binding of the splicing factor HuR to the specific motif in intron 22 of ZO1 and spliceosome recognition of the weak 3' and 5' splice sites in exon 23 to promote exon 23 inclusion. Since exon 23 inclusion in ZO1 suppresses migration and invasion of CRC cells, our findings suggest a novel potential therapeutic target for CRC.

Methylation status of ADAM12 promoter are associated with its expression levels in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is a kind of malignant tumor of digestive system severely affecting human health. The occurrence of CRC is a polygenic and multi-step complex process involving genetic and epigenetic alterations. ADAM12 (a disintegrin and metalloproteases 12), is a gene that was commonly hypermethylated in esophageal cancer using whole-genome methylation microarray in our previous study. METHODS: We detected the methylation frequencies of the CpG island in ADAM12 promoter using bisulfite-pyrosequencing in CRC cell lines and tissue samples. The expression of ADAM12 was detected by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC). A systematic and comprehensive analysis of relationship of DNA hypermethylation and ADAM12 expression in CRC was performed in our samples and TCGA database. RESULTS: The expression of ADAM12 in hypermethylated cell lines was significantly lower than that in hypomethylated cell lines, and demethylation agent 5-Aza-dC could demethylate ADAM12 promoter region and reactivate ADAM12 expression effectively. In 74 pairs of colorectal cancer and normal tissues, bisulfite-pyrosequencing results showed significantly hypermethylation of ADAM12 in CRC compared with adjacent normal mucosa, accompanied with lower expression of ADAM12 in CRC tissues compared to that of the normal tissues. In addition, there was a statistically significant negative correlation between ADAM12 protein expression and methylation levels (rho =-0.28, p = 0.015). CONCLUSION: Promoter hypermethylation was probably a mechanism of ADAM12 epigenetic silencing in CRC.