Fudong Yu

LncRNA‐ATB mediated E‐cadherin repression promotes the progression of colon cancer and predicts poor prognosis

Long non‐coding RNA‐activated by TGF‐β (lncRNA‐ATB) promotes the invasion–metastasis cascade in hepatocellular carcinoma via downregulating E‐cadherin (E‐cad) and inducing epithelial‐to‐ mesenchymal transition (EMT) and is clinically significant in human colon cancer. However, its molecular mechanisms in colon cancer progression remain unclear. This study aimed to elucidate the role of lncRNA‐ATB and its clinical value in colon cancer.

MicroRNA-20a-5p promotes colorectal cancer invasion and metastasis by downregulating Smad4

Background Tumor metastasis is one of the leading causes of poor prognosis for colorectal cancer (CRC) patients. Loss of Smad4 contributes to aggression process in many human cancers. However, the underlying precise mechanism of aberrant Smad4 expression in CRC development is still little known. Results miR-20a-5p negatively regulated Smad4 by directly targeting its 3′UTR in human colorectal cancer cells. miR-20a-5p not only promoted CRC cells aggression capacity in vitro and liver metastasis in vivo, but also promoted the epithelial-to-mesenchymal transition process by downregulating Smad4 expression. In addition, tissue microarray analysis obtained from 544 CRC patients’ clinical characters showed that miR-20a-5p was upregulated in human CRC tissues, especially in the tissues with metastasis. High level of miR-20a-5p predicted poor prognosis in CRC patients. Methods Five miRNA target prediction programs were applied to identify potential miRNA(s) that target(s) Smad4 in CRC. Luciferase reporter assay and transfection technique were used to validate the correlation between miR-20a-5p and Smad4 in CRC. Wound healing, transwell and tumorigenesis assays were used to explore the function of miR-20a-5p and Smad4 in CRC progression in vitro and in vivo. The association between miR-20a-5p expression and the prognosis of CRC patients was evaluated by Kaplan–Meier analysis and multivariate cox proportional hazard analyses based on tissue microarray data. Conclusions miR-20a-5p, as an onco-miRNA, promoted the invasion and metastasis ability by suppressing Smad4 expression in CRC cells, and high miR-20a-5p predicted poor prognosis for CRC patients, providing a novel and promising therapeutic target in human colorectal cancer.

Zinc-α-2-Glycoprotein: A Candidate Biomarker for Colon Cancer Diagnosis in Chinese Population

Zinc-α-2-glycoprotein (AZGP1) is a 41-kDa secreted glycoprotein, which has been detected in several malignancies. The diagnostic value of AZGP1 in serum of prostate and breast cancer patients has been reported. Analyzing “The Cancer Genome Atlas” data, we found that in colon cancer AZGP1 gene expression was upregulated at transcriptional level. We hypothesized that AZGP1 could be used as a diagnostic marker of colon cancer. First, we confirmed AZGP1 expression was higher in a set of 28 tumor tissues than in normal colonic mucosa tissues by real-time quantitative PCR and western blot in a Chinese population. We verified that serum concentration of AZGP1 was higher in 120 colon cancer patients compared with 40 healthy controls by ELISA (p < 0.001). Then receiver-operating characteristic (ROC) curve analysis was used to evaluate the predictive diagnostic value of AZGP1 in serum. The area under the curve (AUC) of AZGP1 was 0.742 (p < 0.001, 95% confidence interval (CI) = 0.656–0.827) in between the AUC of carcinoembryonic antigen (CEA) and the AUC of CA19-9, suggesting that predictive diagnostic value of AZGP1 is between CEA and Carbohydrate 19-9 (CA19-9). The combination of AZGP1 with traditional serum biomarkers, CEA and CA19-9, could result in better diagnostic results. To further validate the diagnostic value of AZGP1, a tissue microarray containing 190 samples of primary colon cancer tissue paired with normal colonic tissue was analysed and the result showed that AZGP1 was significantly upregulated in 68.4% (130 of 190) of the primary cancer lesions. In contrast, there was a weakly positive staining in 29.5% (56 of 190) of the normal colonic tissue samples (p < 0.001). Leave-one-out cross-validation was performed on the serum data, and showed that the diagnostic value of AZGP1 had 63.3% sensitivity and 65.0% specificity. Combination of AZGP1, CEA and CA19-9 had improved diagnosis value accuracy with 74.2% sensitivity and 72.5% specificity. These results suggest that AZGP1 is a useful diagnostic biomarker in tissues and serum from a Chinese population.

Sirtuin-4 (SIRT4) is downregulated and associated with some clinicopathological features in gastric adenocarcinoma.

BACKGROUND Several members of the SIRT family (SIRT1-7), which are a highly conserved family of NAD(+)-dependent enzymes, play an important role in tumor formation. Recently, several studies have suggested that SIRT4 can regulate glutamine metabolism yet have tumor suppressor function too. However, our understanding of SIRT4 expression and its association with the clinicopathological parameters remains poor. METHOD We evaluated SIRT4 protein expression levels in gastric adenocarcinoma and corresponding normal gastric tissue by immunohistochemical staining on a tissue microarray that included 75 gastric adenocarcinoma patients. We also determined the association between SIRT4 expression levels and selected clinicopathological parameters in gastric adenocarcinoma. RESULTS We found that the expression level of SIRT4 in gastric adenocarcinoma was significantly lower than the corresponding normal tissue levels (P=0.003). Besides, lower SIRT4 levels were observed in pathological grade (P=0.002), depth of tumor invasion (P=0.034), positive lymph node numbers (P=0.005) and UICC stage (P=0.002). CONCLUSIONS Our results support the notion that SIRT4 behaves as a tumor suppressor at the human tissue protein level. In addition, our data indicate that SIRT4 might be closely involved in the process of gastric adenocarcinoma development and it might potentially serve as a diagnostic biomarker and therapeutic target in gastric adenocarcinoma.

Overexpression of HOXA10 promotes gastric cancer cells proliferation and HOXA10+/CD44+ is potential prognostic biomarker for gastric cancer

Gastric cancer (GC) is a malignant cancer with poor prognosis. This study aims to investigate the roles of homeobox A10 (HOXA10) in GC and the correlations between HOXA10/CD44 expression and GC prognosis. Based on qRT-PCR and Western Blot analyses in 50 pairs of fresh GC samples and adjacent normal samples, it is identified that HOXA10 was significantly up-regulated in GC tissues at mRNA and protein levels. Cell proliferation, migration, and invasion were enhanced in GC cells with overexpressed HOXA10, while inhibited in cells with silenced HOXA10. Through IPA software, HOXA10 was predicted to interact with CD44 via MSN, which was preliminarily confirmed by using Western Blot. Through immunohistochemistry and tissue microarray (N=264), it is found that HOXA10 expression was significantly correlated with tumor size (P=0.011) and CD44 expression (P<0.001), while CD44 expression was significantly correlated with tumor size (P<0.001), depth of tumor invasion (P<0.001), lymph node metastasis (P<0.001), distant metastasis (P=0.001), UICC stage (P<0.001), histological differentiation (P<0.001), and HOXA10 expression (P<0.001). Additionally, the over-all survival and disease-free survival of HOXA10(+)/CD44(+) patients were dramatically decreased in comparison with that of HOXA10(+)/CD44(-), HOXA10(-)/CD44(+), or HOXA10(-)/CD44(-) patients (P<0.001), suggesting that the combinatory expression of HOXA10 and CD44 was correlated with poor GC prognosis. In conclusion, HOXA10 and CD44 might play roles in GC tumorigenesis, metastasis, and invasion. HOXA10(+)/CD44(+) expression might serve as a prognostic biomarker for GC, which needs more studies to validate.

Clinical and therapeutic significance of sirtuin-4 expression in colorectal cancer

Several members of the sirtuin family (SIRT1-7), which are a highly conserved family of NAD+-dependent enzymes, play an important role in tumor formation. Recent studies indicate that SIRT4 acts as a tumor suppressor by regulating glutamine metabolism. In the present study, we investigated the expression and activity of SIRT4 in colorectal cancer. Using a tissue microarray of 89 colorectal cancer cases, we found that SIRT4 was significantly downregulated in colorectal cancer tissues compared with that noted in the corresponding normal tissue (P<0.001). Lower SIRT4 levels were associated with worse pathological differentiation (P=0.031) and poorer post-operative overall survival rate (P=0.041). We found that SIRT4 overexpression inhibited the proliferation of colorectal cancer cells in vitro and in vivo. SIRT4 inhibited the glutamine metabolism of colorectal cancer cells and synergistically with glycolysis inhibitors induced cell death. SIRT4 also increased the sensitivity of colorectal cancer cells to chemotherapeutic drug 5-fluorouracil by inhibiting the cell cycle. Together, these results highlight the prognostic value of SIRT4 in colorectal cancer and the potential application of SIRT4 in colorectal cancer treatment.

Elevated HOXA1 expression correlates with accelerated tumor cell proliferation and poor prognosis in gastric cancer partly via cyclin D1.

BackgroundHOXA1 is a member of the Homeobox gene family, which encodes a group of highly conserved transcription factors that are important in embryonic development. However, it has been reported that HOXA1 exhibits oncogenic properties in many malignancies. This study focused on the expression and clinical significance of HOXA1 in gastric cancer (GC).MethodsTo assess the mRNA and protein expression of HOXA1 and cyclin D1 in GC tissues, we utilized qRT-PCR and western blotting, respectively. The effects of HOXA1 on GC cell proliferation, migration, and invasion, as well as xenograft tumor formation and the cell cycle were investigated in our established stable HOXA1 knockdown GC cell lines. The protein expression of HOXA1 and cyclin D1 was examined by immunohistochemistry using GC tissue microarrays (TMA) to analyze their relationship on a histological level. The Kaplan-Meier method and cox proportional hazards model were used to analyze the relationship of HOXA1 and cyclin D1 expression with GC clinical outcomes.ResultsHOXA1 mRNA and protein expression were upregulated in GC tissues. Knockdown of HOXA1 in GC cells not only inhibited cell proliferation, migration, and invasion in vitro but also suppressed xenograft tumor formation in vivo. Moreover, HOXA1 knockdown induced changes in the cell cycle, and HOXA1 knockdown cells were arrested at the G1 phase, the number of cells in S phase was reduced, and the expression of cyclin D1 was decreased. In GC tissues, high cyclin D1 mRNA and protein expression were detected, and a significant correlation was found between the expression of HOXA1 and cyclin D1. Survival analysis indicated that HOXA1 and cyclin D1 expression were significantly associated with disease-free survival (DFS) and overall survival (OS). Interestingly, patients with tumors that were positive for HOXA1 and cyclin D1 expression showed worse prognosis. Multivariate analysis confirmed that the combination of HOXA1 and cyclin D1 was an independent prognostic indicator for OS and DFS.ConclusionOur data show that HOXA1 plays a crucial role in GC development and clinical prognosis. HOXA1, alone or combination with cyclin D1, may serve as a novel prognostic biomarker for GC.

Decreased MALL expression negatively impacts colorectal cancer patient survival

The aim of the present study was to determine whether MALL expression is associated with colon cancer progression and patient survival. MALL mRNA expression was reduced in the tumor tissues of 70% of the colon cancer patients and 75% of the rectal cancer patients as compared to their normal tissues. MALL protein was also significantly reduced in the tumor tissues of colon cancer patients (P < 0.001). Increased LOH and methylation of MALL was observed in tumor tissues as compared to normal tissues. Reduced MALL expression was associated with vessin invasion, disease recurrence and metastasis or death (P ≤ 0.027). Furthermore, patients with MALL-negative tumors had significantly decreased overall survival (OS) and disease-free survival (DFS) (P < 0.008 and P < 0.011, respectively). Univariate analysis indicated that MALL expression was significantly associated with OS and DFS. Finally, overexpression of MALL suppressed HCT116 and SW480 cell proliferation and inhibited HCT116 migration. MALL may play a role in colorectal cancer progression as suppression of its expression in tumor tissues negatively impacts colorectal cancer patient survival. Further analyses are required to determine if reduced MALL expression is due to LOH and/or methylation.

Up-regulation of CHAF1A, a poor prognostic factor, facilitates cell proliferation of colon cancer

Deregulation of chromatin assembly factor 1, p150 subunit A (CHAF1A) has recently been reported to be involved in the development of some cancer types. In this study, we identified that the frequency of positive CHAF1A staining in primary tumor mucosa (45.8%, 93 of 203 samples) was significantly elevated compared to that in paired normal mucosa (18.7%, 38 of 203 samples). The increased expression was strongly associated with cancer stage, tumor invasion, and histological grade. The five-year survival rate of patients with CHAF1A-positive tumors was remarkably lower than that of patients with CHAF1A-negative tumors. Colon cancer cells with CHAF1A knockdown exhibited decreased cell growth index, reduction in colony formation ability, elevated cell apoptosis rate as well as impaired colon tumorigenicity in nude mice. Hence, CHAF1A upregulation functions as a poor prognostic indicator of colon cancer, potentially contributing to its progression by mediating cancer cell proliferation.

A comparative analysis and guidance for individualized chemotherapy of stage II and III colorectal cancer patients based on pathological markers

Adjuvant chemotherapy is considered the standard of care for patients with colorectal cancer after curative resection. Although current guidelines provide clear instructions for chemotherapy for stage II high-risk and stage III colorectal cancer, it is insufficient to individualize therapy. We analyzed the outcomes of 902 patients with colorectal cancer treated with or without chemotherapy in our hospital. We found Chinese survival benefit for chemotherapy was consistent with current guidelines. Moreover, our data added to the evidence that chemotherapy might be used for elderly patients with stage II high-risk colorectal cancer. Pathological markers could predict response to individualize therapy in a convenient, fast and inexpensive way. We compared survivals of patients with stage II high-risk and stage III colorectal cancer with chemotherapy in different pathological markers expression, and furthermore used 458 colon adenocarcinoma samples from The Cancer Genome Atlas to verify our preliminary results. We confirmed TOPIIα, EGFR and P170 may be sufficiently predictive markers to individualize chemotherapy. FOLFOX was the optimal adjuvant chemotherapy for patients with stage II high-risk and stage III colorectal cancer when TOPIIα was positive or EGFR or P170 was negative.