MicroRNA-320c inhibits tumorous behaviors of bladder cancer by targeting Cyclin-dependent kinase 6

Background

Increasing evidence has suggested that dysregulation of microRNAs (miRNAs) could contribute to human disease including cancer. Previous miRNA microarray analysis illustrated that miR-320c is down-regulated in various cancers. However, the roles of miR-320c in human bladder cancer have not been well elucidated. Therefore, this study was performed to investigate the biological functions and molecular mechanisms of miR-320c in human bladder cancer cell lines, discussing whether it could be a therapeutic biomarker of bladder cancer in the future.

Methods

Two human bladder cancer cell lines and samples from thirteen patients with bladder cancer were analyzed for the expression of miR-320c by quantitative RT-PCR. Over-expression of miR-320c was established by transfecting mimics into T24 and UM-UC-3. Cell proliferation and cell cycle were assessed by cell viability assay, flow cytometry and colony formation assay. Cell motility ability was evaluated by transwell assay. The target gene of miR-320c was determined by luciferase assay, quantitative RT-PCR and western blot. The regulation of cell cycle and mobility by miR-320c was analyzed by western blot.

Results

We observed that miR-320c was down-regulated in human bladder cancer tissues and bladder cancer cell lines T24 and UM-UC-3. Over-expression of miR-320c could induce G1 phase arrest in UM-UC-3 and T24 cells, and subsequently inhibited cell growth. We also indentified miR-320c could impair UM-UC-3 and T24 cell motility. In addition, we identified CDK6, a cell cycle regulator, as a novel target of miR-320c. Moreover, we demonstrated miR-320c could induce bladder cancer cell cycle arrest and mobility via regulating CDK6. We also observed that inhibition of miR-320c or restoration of CDK6 in miR-320c-over-expressed bladder cancer cells partly reversed the suppressive effects of miR-320c.

Conclusions

miR-320c could inhibit the proliferation, migration and invasion of bladder cancer cells via regulating CDK6. Our study revealed that miR-320c could be a therapeutic biomarker of bladder cancer in the future.

Systematic review and meta-analysis of the effect of alcohol intake on the risk of urolithiasis including dose-response relationship

OBJECTIVE

We conducted a meta-analysis to quantitatively evaluate the correlation between alcohol consumption and the risk of urolithiasis by summarizing the results of published case-control and cohort studies and the potential dose-response association.

METHODS

A systematic literature search of articles up to February 2014 was conducted via PubMed, Web of Science, Cochrane Library, Scopus, EMBASE, the Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles. Fixed- or random-effect models were used to summarize the estimates of odds ratio (OR) with 95% confidence interval (95% CI) for the highest versus the lowest consumption of alcohol. A dose-response meta-analysis was also conducted.

RESULTS

The pooled OR estimates indicated that alcohol consumption was associated with a decreased risk of urolithiasis (OR=0.683, 95% CI 0.577-0.808). In addition, the dose-response meta-analysis indicated that the rate of urolithiasis decreased by 10% for a 10 g/day increase in alcohol intake (OR=0.898, 95% CI 0.851-0.948). No evidence of publication bias was found by Begg's or Egger's test (p=0.130, p=0.130, respectively).

CONCLUSION

Our meta-analysis indicated that alcohol intake is associated with a decreased risk of urolithiasis.

Composite free-standing films of polydopamine/polyethyleneimine grown at the air/water interface

A polydopamie/polyethyleneimine composite free-standing film is obtained via a facile oxidation and cross-linking process at the air/solution interface.

Prohibitin-2 promotes hepatocellular carcinoma malignancy progression in hypoxia based on a label-free quantitative proteomics strategy

The rapid growth of hepatocellular carcinoma (HCC) leading to tumor hypoxia is a common pathological phenomenon. Meanwhile, tumor hypoxia can promote a change in the biological properties of tumor cells. It may enhance the survival of tumor cells under stress conditions, resulting in resistance to apoptosis and angiogenesis. The moleculars that could modulate the malignant phenotypes of HCC cells remain largely unknown. Based on label-free quantitative proteomic data, we found a significant upregulation of prohibitin-2 (PHB2) in HCC tissues. Treatment of hepatoma cells with small interfering RNAs against PHB2 suppressed cell growth and colony formation, led to G1 phase arrest and sensitized HCC cells to apoptosis. Moreover, inhibition of PHB2 expression dramatically repressed the ability of HCC cells to adapt to hypoxic microenvironments and resist chemotherapy-induced apoptosis. Thus, PHB2 in HCC supports the development and progression of hepatocellular malignancy to hypoxia, and implicates the potential antagonist function of PHB2 in transarterial chemoembolization treatment.

A facile synthesis of stilbene-linked porphyrin dimers via the Wittig reaction

A facile synthesis of free-base and metalated stilbene-linked porphyrin dimers via the Wittig reaction is reported. 5-(4-chloromethylphenyl)-10,15,20-triphenyl porphyrin was prepared by direct chloromethylation of meso-tetraphenylporphyrin as the useful precursor for both the porphyrin-derived Wittig reagent and the monoformylporphyrin. It was found that the stilbene-linked porphyrin dimers were formed with a remarkable sterochemical preference in the cis-form. Their absorption and emission spectra were measured.

A novel model for evaluating the risk of hepatitis B recurrence after liver transplantation

BACKGROUND

Hepatitis B virus (HBV) recurrence is a major risk factor affecting the long-term survival of recipients for liver transplantation (LTx). Therefore, a model that can assess this risk before transplantation is highly desirable.

METHODS

One hundred and eighty-five consecutive liver transplant recipients because of HBV-related end-stage liver diseases were selected. Their perioperative laboratory examination results, treatment protocol and the status of HBV recurrence were the primary parameters used to assess their risk of post-transplant HBV recurrence. A model that may be generally used to evaluate the risk of post-transplant HBV recurrence was thus established. A cohort for further validation and a cross-validation were designed.

RESULTS

After a follow-up time of 26.0 ± 10.8 months, the overall HBV recurrence rate was 8.6%. The 1-, 2- and 3-year cumulative survival rates were 98.5, 89.2 and 83.4% respectively. By correlation with the pretransplant presence of hepatocelluar carcinoma (HCC), serum HBV DNA level and status of antiviral treatment (AVT), the risk assessment model can be summarized using the following equation: RISK=-4.378 + 1.493 × HCC + 1.286 × DNA - 2.426 × AVT. The HBV recurrence rate and survival were found to be significantly different between the recipients with risk scores ≤-2.8 and >-2.8. The model was well validated in this work.

CONCLUSIONS

Pretransplant HBV DNA level, presence of HCC, AVT status and post-transplant viral mutation were identified as the major risk factors associated with HBV recurrence after LTx. A novel model incorporating these factors could effectively evaluate the risk of post-transplant HBV recurrence before transplantation.

Aberrant methylation of the CADM1 promoter is associated with poor prognosis in hepatocellular carcinoma treated with liver transplantation

Approximately 20-40% of hepatocellular carcinoma (HCC) patients who undergo liver transplantation (LT) experience HCC recurrence within 5 years of the operation. Current predictors cannot sufficiently differentiate patients at risk for biochemical recurrence. The aim of the present study was to investigate the methylation status and expression levels of cell adhesion molecule 1 (CADM1) in HCC; to elucidate its regulation mechanisms; and finally, to evaluate the potential predictive value for tumor recurrence. Aberrant hypermethylation of CADM1 was frequently found in HCC cell lines with decreased CADM1 mRNA by bisulfite sequencing PCR. Re-expression of CADM1 was induced by treatment with demethylating agents. The promoter region of CADM1 was identified and the basal promoter activity was located in the -226 to -146 region relative to the transcriptional start site (TSS). Site-directed mutagenesis revealed that the consensus Sp1 binding site located in the basal promoter region was important for mediating CADM1 promoter activity. Furthermore, aberrant hypermethylation of CADM1 was detected in 34 of 82 (41.5%) of HCC tissues. The recurrence rate of the patients with CADM1 methylation was higher compared to that without CADM1 methylation (70.6% versus 33.3%; P=0.001). Multivariate analysis revealed that CADM1 methylation status (HR = 2.788; 95% CI, 1.043-5.063; P=0.010) was an independent prognostic factor for disease-free survival (DFS) of HCC patients treated with LT. In conclusion, CADM1 methylation may be used as a potential predictive biomarker for tumor recurrence of HCC after LT.

The value of serum alpha-fetoprotein in predicting tumor recurrence after liver transplantation for hepatocellular carcinoma

BACKGROUND

Many patients with hepatocellular carcinoma (HCC) who undergo liver transplantation (LT) subsequently develop tumor recurrence; this is the main factor affecting long-term survival after LT. Factors associated with tumor recurrence should be determined to improve the outcome of LT. The purpose of the study was to evaluate the value of alpha-fetoprotein (AFP) in forecasting tumor recurrence after LT for patients with HCC.

METHODS

AFP data before and after LT for 97 patients with HCC who underwent LT in our center were analyzed retrospectively.

RESULTS

The mean follow-up time was 17.1 +/- 2.1 months for all 97 patients, overall tumor recurrence rate was 32.9% (32/97), and mean recurrence time was 7.2 +/- 3.2 months. The most common tumor recurrence sites were liver, lung, skeleton, and other sites. Pre-transplant AFP levels >400 ng/ml were associated with higher tumor recurrence. Post-transplant AFP levels not decreasing to <or=20 ng/ml within 2 months were also indicative of higher risk of recurrence.

CONCLUSIONS

Pre-transplant AFP and the dynamic change of AFP after LT were valuable in predicting tumor recurrence after LT for patients with HCC.