Guoqiang Qiu

Long non-coding RNA HOTAIR is a powerful predictor of metastasis and poor prognosis and is associated with epithelial-mesenchymal transition in colon cancer.

Colon cancer is one of the most frequently diagnosed cancer and the third most fatal malignancy worldwide. HOTAIR, a cancer-associated long non-coding RNA (lncRNA), is a powerful biomarker of metastasis and poor prognosis in a diverse group of cancers. Nevertheless, an understanding of how HOTAIR is involved in colon cancer progression is limited. In the present study, we hypothesized that HOTAIR plays a crucial role in colon cancer development. We evaluated the expression of HOTAIR in 120 colon cancer samples, matched adjacent non-tumor mucosa and 32 lymph node metastasis tissues by real-time PCR. Increased HOTAIR expression was significantly correlated with the depth of tumor invasion, lymph node metastasis, organ metastasis, histological differentiation, vascular invasion and advanced tumor stage. Patients with high HOTAIR expression had higher recurrence rates and reduced metastasis-free and overall survival than patients with low HOTAIR expression. Moreover, our findings revealed that HOTAIR had a limited effect on cell proliferation but significantly promoted colon cancer cell migration and invasion in vitro. Depletion of HOTAIR increased the expression of E-cadherin while concomitantly decreasing expression of vimentin and MMP9. Hence, HOTAIR may be another pleiotropic modulator participating in epithelial-mesenchymal transition (EMT). These results indicate that HOTAIR may also be a valuable predictor for colon cancer management; furthermore, this lncRNA may be a potential target for cancer prevention and treatment.

Identification of recurrence-related microRNAs in hepatocellular carcinoma following liver transplantation.

Tumor recurrence‐related microRNAs (miRNAs) in hepatocellular carcinoma (HCC) following orthotopic liver transplantation (OLT) are not clear yet. This study was designed to determine whether altered miRNA expression is associated with HCC recurrence and prognosis following OLT. 18 miRNAs, including 6 up‐regulated and 12 down‐regulated miRNAs were identified by microarray in primary HCC samples of patients who had developed HCC recurrence (n = 5) compared to those with non‐recurrence (n = 5) following OLT by using p < 0.05 as cutoff value. The six most significantly altered miRNAs (fold change ≥ 2: miR‐19a, miR‐886‐5p, miR‐126, miR‐223, miR‐24 and miR‐147) were further confirmed by qRT‐PCR in the remaining 105 HCC samples. In receiver‐operating characteristic curve analysis, this six miRNAs were of high sensitivity and specificity in predicting HCC recurrence. Using Cox regression and risk score analysis, we built a six‐miRNA signature based on their qRT‐PCR readings for the prediction of outcome of HCC following OLT. Kaplan–Meier and Cox proportional regression revealed this six‐miRNA signature was a significant independent predictor of overall survival (log‐rank p = 0.020) and recurrence‐free survival (log‐rank p < 0.001). Finally, the data were further reconfirmed in an independent cohort of 50 patients from another transplant center. In addition, bioinformatics Gene Ontology and pathway analysis were also performed to better understand the critical roles of these miRNAs in HCC recurrence. Our study, in addition to suggesting a different miRNA expression pattern between HCC samples of patients with recurrence and those with non‐recurrence, proposes that this six‐miRNA signature may serve as biomarker for prognosis of HCC patients following OLT.

Phospholipase C epsilon plays a suppressive role in incidence of colorectal cancer

In our previous study, we have found that PLCE1 was down-regulated in sporadic colorectal cancer. But the role of PLCE1 in the incidence of colorectal cancer is still not definite. Therefore, in order to validate whether PLCE1 displays a suppressive role, in this study, we examined the expression of PLCE1 in sporadic colorectal cancer with a larger sample size and the effect of PLCE1 overexpression on cancer cell malignant degree. The expression level of PLCE1 in 50 colorectal cancers with their pair-matched normal tissues was measured by RT-PCR, Western blot, and immunohistochemistry. The effect of PLCE1 overexpression on cancer cell malignant degree was measured by MTT assay, plate colony formation assay, soft agar colony formation assay, cell cycle and apoptosis analysis, and xenograft assay. We found that PLCE1 was down-regulated in 42% (21/50) of colorectal cancer tissues compared with pair-matched normal tissues, more frequent in the poor differentiation tumor in patients under 60. Overexpression of PLCE1 significantly inhibited the proliferation of colon cancer cells and degraded its malignant degree. These results suggest that PLCE1 may be involved in the development of sporadic colorectal cancer through its inhibitory effect on cell proliferation. PLCE1 exhibits a suppressive role in incidence of colorectal cancer.

Biglycan expression correlates with aggressiveness and poor prognosis of gastric cancer

Biglycan, a member of the small leucine-rich proteoglycan family, has been implicated in the development and progression of human cancers. However, the clinical significance of biglycan expression in gastric cancer has not been determined. In the present study, biglycan mRNA and protein concentrations were analyzed using quantitative realtime reverse transcription polymerase chain reaction and Western blot in 69 gastric cancer and adjacent non-tumorous tissues, respectively. Biglycan expression was further assessed using immunohistochemistry in tissue microarrays that contained 264 cases of gastric cancer, and others containing normal or metastasized lymph node tumor tissues. Biglycan was upregulated at the transcriptional and translational levels and there was a correlation between the expression of biglycan mRNA and protein (P = 0.000, κ = 0.769). Over-expression of biglycan was strongly associated with lymph node metastasis, tumor (T) classification, metastasis (M) classification, vascular invasion and Union for International Cancer Control (UICC) stage. Patients with biglycan-positive tumors had a significantly higher disease recurrence rate and poorer survival than patients with biglycan-negative tumors after the radical surgery. Multivariate analysis revealed that biglycan expression is an independent prognostic indicator for survival of patients with gastric cancer. The data from the current study demonstrate that elevated expression of biglycan may play an important role in the development and progression of gastric cancer, and could be further evaluated as a biomarker for predication of a poor clinical outcome.

Gene-expression profiling in Chinese patients with colon cancer by coupling experimental and bioinformatic genomewide gene-expression analyses: identification and validation of IFITM3 as a biomarker of early colon carcinogenesis.

Expression microarrays are widely used for investigating the nature and extent of global gene‐expression changes in human cancer. Accurate genomewide gene‐expression profiles have not been conducted in colon tumor and normal colon tissue specimens obtained from Chinese patients.

Decreased Expression of RASSF6 Is a Novel Independent Prognostic Marker of a Worse Outcome in Gastric Cancer Patients after Curative Surgery

BackgroundOur previous study observed that the expression of RASSF6, a member of the Ras-association domain family, was down-regulated in gastric cancer cells. The present study further investigated the clinical significance of RASSF6 in gastric cancer.MethodsUsing real-time PCR, Western blot analysis, tissue microarray (TMA), and immunohistochemical staining, we evaluated RASSF6 mRNA and protein levels in tumor tissues and in the paired adjacent normal mucosa from patients with gastric cancers at different stages.ResultsRASSF6 mRNA and protein levels were decreased in gastric cancer tissues compared with the adjacent normal mucosa. Immunohistochemical detection of RASSF6 in a TMA that contained 264 paired specimens showed that a decreased cytoplasmic RASSF6 expression was significantly associated with the extent of cancer invasion, lymph node metastasis, distant metastasis, tumor histological grade, advanced clinical stage, and Ki-67 proliferative index. Moreover, RASSF6 expression in metastatic lymph nodes was lower than in the paired primary tumors. Patients with RASSF6-negative tumors had extremely higher disease recurrence rates and poorer survival than patients with RASSF6-positive tumors even after radical surgery. Stratification analysis revealed RASSF6 as an independent predictor for tumor recurrence in patients with gastric cancers irrespective of tumor stage.ConclusionsRASSF6 might contribute to the progression of gastric carcinogenesis and may function as a novel independent prognostic marker for the prediction of the recurrence of cancer in patients after curative operations.

Identification and validation of Kallikrein-ralated peptidase 11 as a novel prognostic marker of gastric cancer based on immunohistochemistry †‡

It is important to identify and validate the differentially expressed genes in gastric cancer to screen diagnostic and/or prognostic tumor markers.

Genome-wide search for loss of heterozygosity in Chinese patients with sporadic colorectal cancer

In an attempt to integrally investigate the loss of tumor suppressor genes and search for putative suppressor loci associated with tumor occurrence and progression, we conducted a genome-wide loss of heterozygosity (LOH) study of 83 tumor samples obtained from Chinese patients with sporadic colorectal cancer. We employed 400 fluorescence-labeled microsatellite marker primers to amplify the corresponding loci of the genomic DNA and then electrophoresed the polymerase chain reaction products and analyzed the fluorescent signals. The LOH frequencies were high (>35%) but were not associated with the tumor stage and progression in 20 loci, including the regions where TP53, E-cadherin, deleted in colorectal carcinoma (DCC), phosphatase and tensin homolog deleted on chromosome 10 (PTEN), mothers against decapentaplegic, Drosophila, homolog of 2 (MADH2) and mothers against decapentaplegic, Drosophila, homolog of 4 (MADH4) reside. Loss of other loci, including two narrow regions on chromosome 2, was found to relate to the tumor stage, suggesting that this genomic instability may contribute to tumor progression.

Digital Transcript Profile Analysis with aRNA-LongSAGE Validates FERMT1 As a Potential Novel Prognostic Marker for Colon Cancer

Purpose: To use gene transcript profiling to identify cancer-associated gene expression. Experimental Design: Methods included (i) marker discovery using laser capture microdissection (LCM)-assisted specimen preparation and antisense RNA-long serial analysis of gene expression (aRNA-LongSAGE) on matched colon cancer and uninvolved colon tissue specimens (n = 5). Candidate tumor-associated genes were selected by combining the LongSAGE libraries reported herein with our previous colon cancer LCM-microarray transcript profiling data; (ii) marker selection and validation by quantitative real-time PCR (n = 15) and immunohistochemistry (n = 31); and (iii) independent validation on multiple tissue microarray (n = 203). Results: Among 30 upregulated and 73 downregulated genes, upregulation of fermitin family member 1 (FERMT1), adenosylhomocysteinase (AHCY), secernin 1 (SCRN1), and SAC3 domain-containing protein 1 (SAC3D1) expression and downregulation of IgJ and MALL expression in colon cancer were confirmed by quantitative PCR. FERMT1 and AHCY protein expression was also upregulated in colon cancer compared with uninvolved colon mucosa, and FERMT1 expression showed upregulation in colon adenoma. Patients with moderate/strong tumor FERMT1 protein expression (n = 122) showed significantly poorer overall survival (OS; P = 0.011) and disease-free survival (DFS; P = 0.005) than patients with negative/weak tumor FERMT1 protein expression (n = 81). Multivariate Cox regression analysis showed that FERMT1 protein expression was also an independent prognostic factor for OS (P = 0.018) and DFS (P = 0.009). In addition, upregulated FERMT1 protein expression appeared to have some specificity among alimentary tract tumors. Conclusions: FERMT1 is a novel prognostic factor for colon carcinoma. Clin Cancer Res; 17(9); 2908–18. ©2011 AACR.

Overexpression of Reg4, alone or combined with MMP-7 overexpression, is predictive of poor prognosis in colorectal cancer.

Regenerating islet-derived family, member 4 (Reg4) is a secreted protein that plays a critical role in the development of colorectal cancer (CRC). In the present study, we examined the relationship between Reg4 and matrix metalloproteinase-7 (MMP-7) expression in CRC, particularly with regard to metastasis. RT-qPCR, western blotting, tissue microarray (TMA) and immunohistochemical staining were performed to detect Reg4 and MMP-7 expression in CRC tissues and paired adjacent normal tissues. As compared with normal tissues, most paired colon cancers showed a ≥2-fold increase in the Reg4 and MMP-7 mRNA levels, which was subsequently validated by the post-transcriptional levels. Immunohistochemical analysis demonstrated that Reg4 was associated with lymph node and distant metastasis, advanced American Joint Committee on Cancer (AJCC) stage, and histologic grade. Further studies showed the correlation between Reg4 and MMP-7 expression was significant in CRC with distant metastasis (r=0.555, P=0.021) and in the lymph‑node metastasis samples (r=0.557, P<0.001). Patients with tumor positivity for the two molecules showed a worse prognosis even after radical surgery (P<0.001). Multivariate analysis revealed that patients with Reg4- and MMP-7-positive tumors had extremely poor OS (HR 4.63; 95% CI 2.43-8.81; P<0.001) and DFS (HR 3.88; 95% CI 2.08-7.22; P<0.001). Reg4 expression may be useful in the prediction of colon cancer prognosis when combined with MMP-7.