Zong-Guang Zhou

Clinicopathological significance of microRNA-31, -143 and -145 expression in colorectal cancer

We are just beginning to understand how microRNAs (miRNAs) are involved in tumor-related processes in humans. Applying real-time RT-PCR, we investigated the miR-31, miR-143 and miR-145 expression in 98 primary CRC specimens, along with the corresponding normal mucosa specimens, and analyze the relationship of their expression with clinicopathological features. Our results showed the miR-31 expression was up-regulated in CRC compared to normal mucosa (p = 0.001). Furthermore, miR-31 expression was positively related to advanced TNM stage (p = 0.026) and deeper invasion of tumors (p = 0.024). MiR-145 was down-regulated in both colon (p = 0.001) and rectal (p = 0.012) cancer. MiR-143 was only down-regulated in colon cancer (p = 0.023) but not in rectal cancer (p = 0.351). There was no relationship of miR-143 and miR-145 expression with other clinicopathological features (p > 0.05), except that the miR-145 expression was related to cancer site (p = 0.03). In conclusion, the miR-31 overexpression may be involved in the development and progression of CRC. The miR-143 and miR-145 may play a certain role in the development of colon and/or rectal cancers but not in progression of the disease.

Survivin expression quantified by Image Pro-Plus compared with visual assessment.

Over the past decades, immunohistochemistry has gained significance and already taken a crucial position in diagnosis of diseases and prognosis of patients. However, manual interpretation of immunohistochemistry and reproducibility of the scoring systems can be highly subjective. In the article, the immunohistochemical staining of survivin in 98 rectal cancers was analyzed by using Image Pro-Plus (IPP) [3 parameters: density mean, area sum, and integrated optical density (IOD)] and the results were compared with visual assessment (2 parameters: intensity and percentage). The correlations between the 2 methods were examined, significant correlations were observed between density mean and staining intensity (Spearman correlation coefficient, rs=0.806, P<0.001), IOD and staining intensity (rs=0.914, P<0.001), area sum and staining percentage (rs=0.883, P<0.001), IOD and staining percentage (rs=0.884, P<0.001). There was no significant difference between survivin expression and clinicopathologic variables (P>0.05) by visual assessment. However, by IPP analysis, both the density mean and IOD were higher in better-differentiated cancers than in worse differentiated ones (P=0.02 and 0.03). There was a substantial agreement between the 2 methods. Density mean and IOD of IPP were representative parameters to assess the immunostaining quantification, and increased sensitivity in scoring and provided a more reliable and reproducible analysis of protein expression, especially, more information of the protein expression in relation to clinicopathologic variables can be provided by IPP analysis.

Suppression of microRNA-31 increases sensitivity to 5-FU at an early stage, and affects cell migration and invasion in HCT-116 colon cancer cells

BackgroundMicroRNAs (miRNAs) are endogenously expressed noncoding RNAs with important biological and pathological functions. Although several studies have shown that microRNA-31 (miR-31) is obviously up-regulated in colorectal cancer (CRC), there is no study on the functional roles of miR-31 in CRC.MethodsAnti-miR™ miRNA 31 inhibitor (anti-miR-31) is a sequence-specific and chemically modified oligonucleotide to specifically target and knockdown miR-31 molecule. The effect of anti-miR-31 transfection was investigated by real-time PCR. HCT-116p53+/+ and HCT-116p53-/-colon cancer cells were treated by anti-miR-31 with or without 5-fluorouracil (5-FU), cell proliferation was determined by MTT assay; apoptosis was detected by DAPI staining; cell cycle was evaluated by flow cytometry; colony formation, migration and invasion assays were performed to investigate the effect of suppression of miR-31 on the cell lines.ResultsReal-time PCR results showed that anti-miR-31 was efficiently introduced into the cells and reduced miR-31 levels to 44.1% in HCT-116p53+/+ and 67.8% in HCT-116p53-/-cell line (p = 0.042 and 0.046). MTT results showed that anti-miR-31 alone had no effect on the proliferation of HCT-116p53+/+ or HCT-116p53-/-. However, when combined with 5-FU, anti-miR-31 inhibited the proliferation of the two cell lines as early as 24 h after exposure to 5-FU (p = 0.038 and 0.044). Suppression of miR-31 caused a reduction of the migratory cells by nearly 50% compared with the negative control in both HCT-116p53+/+ and HCT-116p53-/-(p = 0.040 and 0.001). The invasive ability of the cells were increased by 8-fold in HCT-116p53+/+ and 2-fold in HCT-116p53-/- (p = 0.045 and 0.009). Suppression of miR-31 had no effect on cell cycle and colony formation (p > 0.05).ConclusionsSuppression of miR-31 increases sensitivity to 5-FU at an early stage, and affects cell migration and invasion in HCT-116 colon cancer cells.

Correlation of SATB1 overexpression with the progression of human rectal cancer.

Background and aimsTo date, the association between special AT-rich sequence-binding protein 1 (SATB1) and colorectal cancer (CRC) has not been reported. This study was aimed at investigating the expression and potential role of SATB1 in human rectal cancers.MethodsNinety-three paired samples of rectal cancer and distant normal rectal tissue were analyzed by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC), and the correlations between SATB1 expression and clinicopathological parameters were evaluated. The expression profiles of SATB1 were also investigated in a panel of five human colon carcinoma cell lines.ResultsThe general level of SATB1 mRNA in rectal cancer tissues was statistically significantly higher than that in normal mucosa (P = 0.043). The rate of positive SATB1 protein expression in rectal cancers (44.1%) was significantly higher than that in normal tissues (25.8%) by IHC analysis (P = 0.009). Overexpression of SATB1 mRNA was more predominant in patients with earlier onset of rectal cancer (P = 0.033). SATB1 expression correlated with invasive depth and tumor node metastasis (TNM) stage at both protein and mRNA levels (P < 0.05). Furthermore, SATB1 expression in the poorly metastatic KM12C cells was significantly lower than the highly metastatic KM12SM and KM12L4A cells and higher than the HCT116 and SW480 cells (P = 0.001). These results were further confirmed by Western blotting.ConclusionOur results indicate that SATB1 may play an important role in the progression of human rectal cancer, which represents a possible new mechanism underlying CRC.

Toll-like receptor 4 detected in exocrine pancreas and the change of expression in cerulein-induced pancreatitis.

Objectives: To detect Toll-like receptor 4 (TLR4) expression and distribution in rat pancreas and the change of TLR4 expression in cerulein-induced pancreatitis (CIP). Methods: Acute pancreatitis was induced by subcutaneous injections of cerulein at a total dose of 20 μg/kg. Immunohistochemistry (IHC) was used to detect and localize TLR4 in rat pancreas, and real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to quantitatively determine the expression of TLR4 mRNA in CIP. Results: IHC showed the presence of TLR4 in rat pancreas, and its distribution was specifically localized to pancreatic ductal epithelium, vascular endothelium, and islet. No TLR4 staining was detected in exocrine acinar cells. Real-time RT-PCR results revealed low-level TLR4 mRNA expression in the rat pancreas, and the change of TLR4 in CIP only developed within the first 4 hours, which is a rapid up-regulation process that peaks at the first hour. TLR4 mRNA was sustained at baseline level from 4 to 24 hours. Conclusions: TLR4 protein was expressed in pancreas and localized to epithelial (pancreatic duct) or endothelial (vessels) tissues; TLR4 responded favorably to the inflammatory process, and the change of expression was characterized as a rapid up-regulation in the early stage of CIP.

Laparoscopic management of severe acute pancreatitis.

Introduction Severe acute pancreatitis (SAP) remains a serious disease state difficult to manage. Laparoscopic surgery represents a relatively new solution to this problem. This study was aimed to investigate the feasibility of laparoscopic treatment of SAP and the selection of laparoscopic procedures in various stages of SAP according to different pathologic alterations. Methods Thirteen patients, 9 men and 4 women with an average age of 46 years old, were diagnosed with SAP. Laparoscopic necrosectomy followed by external drainage were performed on 7 patients with massive fluid collections and/or infected necrosis in acute reaction phase of SAP. For 2 cases in subacute phase characterized by fresh-formed adhesions and encapsulation, laparoscopic intracavitary debridement experienced difficulty. For the other 4 patients in late phase with well-defined pancreatic or peripancreatic pseudocyst/abscess, ultrasound-guided, directly visualized laparoscopic intracavitary debridement, and external drainage were carried out with ease and efficiency. Results Laparoscopic procedures were accomplished successfully on 12 patients (92.3%), except for 1 conversion (7.7%) to open laparotomy owing to poor exposure and hard maneuvers in subacute phase. There was no mortality in this group. Patients were witnessed to have accelerated recovery following laparoscopic surgery. Conclusion Laparoscopic technique offers new hope for the treatment of SAP. It is recommended as a feasible, effective, and less traumatic therapeutic means on condition that the strategy of individualization is followed.

Prognostic value of cancer stem cell marker CD133 expression in gastric cancer: a systematic review.

Objective To investigate the correlation between CD133-positive gastric cancer and clinicopathological features and its impact on survival. Methods A search in the Medline and Chinese CNKI (up to 1 Dec 2011) was performed using the following keywords gastric cancer, CD133, AC133, prominin-1 etc. Electronic searches were supplemented by hand searching reference lists, abstracts and proceedings from meetings. Outcomes included overall survival and various clinicopathological features. Results A total of 773 gastric cancer patients from 7 studies were included. The median rate of CD133 expression by immunohistochemistry (IHC) was 44.8% (15.2%–57.4%) from 5 studies, and that by reverse transcription polymerase chain reaction (RT-PCR) was 91.3% (66.7%–100%) from 4 studies. The accumulative 5-year overall survival rates of CD133-positive and CD133-negative patients were 21.4% and 55.7%, respectively. Meta-analysis showed that CD133-positive patients had a significant worse 5-year overall survival compared to the negative ones (OR = 0.20, 95% CI 0.14–0.29, P<0.00001). With respect to clinicopathological features, CD133 overexpression by IHC method was closely correlated with tumor size, N stage, lymphatic/vascular infiltration, as well as TNM stage. Conclusion CD133-positive gastric cancer patients had worse prognosis, and was associated with common clinicopathological poor prognostic factors.

¹H NMR-based metabolic profiling of human rectal cancer tissue

BackgroundRectal cancer is one of the most prevalent tumor types. Understanding the metabolic profile of rectal cancer is important for developing therapeutic approaches and molecular diagnosis.MethodsHere, we report a metabonomics profiling of tissue samples on a large cohort of human rectal cancer subjects (n = 127) and normal controls (n = 43) using 1H nuclear magnetic resonance (1H NMR) based metabonomics assay, which is a highly sensitive and non-destructive method for the biomarker identification in biological systems. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and orthogonal projection to latent structure with discriminant analysis (OPLS-DA) were applied to analyze the 1H-NMR profiling data to identify the distinguishing metabolites of rectal cancer.ResultsExcellent separation was obtained and distinguishing metabolites were observed among the different stages of rectal cancer tissues (stage I = 35; stage II = 37; stage III = 37 and stage IV = 18) and normal controls. A total of 38 differential metabolites were identified, 16 of which were closely correlated with the stage of rectal cancer. The up-regulation of 10 metabolites, including lactate, threonine, acetate, glutathione, uracil, succinate, serine, formate, lysine and tyrosine, were detected in the cancer tissues. On the other hand, 6 metabolites, including myo-inositol, taurine, phosphocreatine, creatine, betaine and dimethylglycine were decreased in cancer tissues. These modified metabolites revealed disturbance of energy, amino acids, ketone body and choline metabolism, which may be correlated with the progression of human rectal cancer.ConclusionOur findings firstly identify the distinguishing metabolites in different stages of rectal cancer tissues, indicating possibility of the attribution of metabolites disturbance to the progression of rectal cancer. The altered metabolites may be as potential biomarkers, which would provide a promising molecular diagnostic approach for clinical diagnosis of human rectal cancer. The role and underlying mechanism of metabolites in rectal cancer progression are worth being further investigated.

RNA Interference Against Peroxisome Proliferator-Activated Receptor δ Gene Promotes Proliferation of Human Colorectal Cancer Cells

PurposeThis study was designed to investigate the effects of peroxisome proliferator-activated receptor δ (PPAR δ) on the proliferation and apoptosis of human colorectal cancer cells.MethodsFor RNA interfering (RNAi), HCT-116 cells were transfected with short hairpin RNA (shRNA)-expressing plasmids against PPAR δ or negative control vectors, and the stably transfected cells were selected with G418. The efficacy of RNAi was assessed by real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blotting analysis. The proliferation, cell cycle, and apoptosis of HCT-116 cells treated by RNAi, compared with those containing control vectors or untreated, were analyzed respectively by using MTT (methyl thiazolyl tetrazolium), flow cytometry, and TdT (terminal deoxynucleotidyl transferase)-mediated dUTP nick end-labeling (TUNEL) assay.ResultsRNAi targeting PPAR δ resulted in substantial suppression of PPAR δ expression and significantly promoted the proliferation of HCT-116 cells relative to those with control vectors or untreated, obviously decreasing the frequency of G1-phase cells but had no effect on cell apoptosis.ConclusionsPPAR δ may inhibit the proliferation of CRC cells and increase the number of cells in G1 phase, without any function in cell apoptosis.

Erianin induces G2/M-phase arrest, apoptosis, and autophagy via the ROS/JNK signaling pathway in human osteosarcoma cells in vitro and in vivo.

Erianin, a natural product derived from Dendrobium chrysotoxum, has exhibited potential antitumor activity in various malignancies, including hepatocarcinoma, melanoma, and promyelocytic leukemia. Here we explored the effects of erianin on osteosarcoma (OS) in vitro and in vivo and further elucidated the underlying molecule mechanisms. In this study, we found that erianin potently suppressed cell viability in various OS cell lines. Treatment with erianin induced G2/M-phase arrest, apoptosis, and autophagy in OS cells. Further studies showed that erianin-induced apoptosis and autophagy was attributed to reactive oxygen species (ROS), as N-acetyl cysteine (NAC), an ROS scavenger, attenuated them. Moreover, we found that erianin induced activation of c-Jun N-terminal kinase (JNK) signal pathway, which was also blocked by NAC. Downregulation of JNK by its specific inhibitor SP600125 could attenuate apoptosis and autophagy induced by erianin. Finally, erianin in vivo markedly reduced the growth with little organ-related toxicity. In conclusion, erianin induced cell cycle G2/M-phase arrest, apoptosis, and autophagy via the ROS/JNK signaling pathway in human OS. In light of these results, erianin may be a promising agent for anticancer therapy against OS.