The potential treatment of N-acetylcysteine as an antioxidant in the radiation-induced heart disease.

Background: Radiation-induced heart disease (RIHD) is a serious complication of thoracic tumor radiotherapy that substantially affects the quality of life of cancer patients. Oxidative stress plays a pivotal role in the occurrence and progression of RIHD, which prompted our investigation of an innovative approach for treating RIHD using antioxidant therapy. Methods: We used 8-week-old male Sprague-Dawley (SD) rats as experimental animals and H9C2 cells as experimental cells. N-acetylcysteine (NAC) was used as an antioxidant to treat H9C2 cells after X-ray irradiation in this study. In the present study, the extent of cardiomyocyte damage caused by X-ray exposure was determined, alterations in oxidation/antioxidation levels were assessed, and changes in the expression of genes related to mitochondria were examined. The degree of myocardial tissue and cell injury was also determined. Dihydroethidium (DHE) staining, reactive oxygen species (ROS) assays, and glutathione (GSH) and manganese superoxide dismutase (Mn-SOD) assays were used to assess cell oxidation/antioxidation. Flow cytometry was used to determine the mitochondrial membrane potential and mitochondrial permeability transition pore (mPTP) opening. High-throughput transcriptome sequencing and bioinformatics analysis were used to elucidate the expression of mitochondria-related genes in myocardial tissue induced by X-ray exposure. Polymerase chain reaction (PCR) was used to verify the expression of differentially expressed genes. Results: X-ray irradiation damaged myocardial tissue and cells, resulting in an imbalance of oxidative and antioxidant substances and mitochondrial damage. NAC treatment increased cell counting kit-8 (CCK-8) levels (P=0.02) and decreased lactate dehydrogenase (LDH) release (P=0.02) in cardiomyocytes. It also reduced the level of ROS (P=0.002) and increased the levels of GSH (P=0.04) and Mn-SOD (P=0.01). The mitochondrial membrane potential was restored (P<0.001), and mPTP opening was inhibited (P<0.001). Transcriptome sequencing and subsequent validation analyses revealed a decrease in the expression of mitochondria-related genes in myocardial tissue induced by X-ray exposure, but antioxidant therapy did not reverse the related DNA damage. Conclusions: Antioxidants mitigated radiation-induced myocardial damage to a certain degree, but these agents did not reverse the associated DNA damage. These findings provide a new direction for future investigations by our research group, including exploring the treatment of RIHD-related DNA damage.

MicroRNA-125b functions as a tumor suppressor in hepatocellular carcinoma cells.

MicroRNAs (miRNAs) are important regulators of multiple cellular processes, and the deregulation of miRNA is a common event in diverse human diseases, particularly cancer. However, the mechanisms underlying the relationship between disordered miRNA expression and tumorigenesis have remained largely unknown. In this study, we demonstrated the down-regulation of miR-125b in hepatocellular carcinoma (HCC) tissues and HCC cell lines by Northern blot and quantitative RT-PCR analyses. The ectopic expression of miR-125b reduced the cellular proliferation and cell cycle progression of HCC cells by targeting Mcl-1 and IL6R. Furthermore, the miR-125b-induced inhibition of cell proliferation was rescued by the expression of Mcl-1 or IL6R variants that lacked 3' UTRs. Thus, this study revealed the differential expression of miR-125b in HCC cells and elucidated its potential as a tumor suppressor in HCC development.

The role of WT1 in breast cancer: clinical implications, biological effects and molecular mechanism.

Although Wilms' tumor gene 1 (WT1) was first cloned and identified as a tumor suppressor gene in nephroblastoma, subsequent studies have demonstrated that it can also play an oncogenic role in leukemia and various solid tumors. WT1 exerts biological functions with high tissue- and cell-specificity. This article reviews the relationship between WT1 and breast cancer from two aspects: (1) clinical application of WT1, including the relationship between expression of WT1 and prognosis of breast cancer patients, and its effectiveness as a target for comprehensive therapy of breast cancer; (2) the biological effects and molecular mechanisms of WT1 in the development and progression of breast cancer, including proliferation, apoptosis, invasion, and metastasis of breast cancer cells.

Indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 expression prediction for adverse prognosis in colorectal cancer.

AIM: To evaluate indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 (IDO1/COX2) expression as an independent prognostic biomarker for colorectal cancer (CRC) patients. METHODS: We retrospectively studied the medical records of 95 patients who received surgical resection from August 2008 to January 2010. All patients were randomly assigned to adjuvant treatment with or without celecoxib groups after surgery. We performed standard immunohistochemistry to assess the expression levels of IDO1/COX2 and evaluated the correlation of IDO1/COX2 with clinicopathological factors and overall survival (OS) outcomes. RESULTS: The expression of nuclear IDO1 was significantly correlated with body mass index (P < 0.001), and IDO1 expression displayed no association with sex, age, tumor differentiation, T stage, N stage, carcinoembryonic antigen, cancer antigen 19-9, CD3+ and CD8+ tumor infiltrating lymphocytes, and COX2. In univariate analysis, we found that nuclear IDO1 (P = 0.039), nuclear/cytoplasmic IDO1 [hazard ratio (HR) = 2.044, 95% confidence interval (CI): 0.871-4.798, P = 0.039], nuclear IDO1/COX2 (HR = 3.048, 95%CI: 0.868-10.7, P = 0.0049) and cytoplasmic IDO1/COX2 (HR = 2.109, 95%CI: 0.976-4.558, P = 0.022) all yielded significantly poor OS outcomes. Nuclear IDO1 (P = 0.041), nuclear/cytoplasmic IDO1 (HR = 3.023, 95%CI: 0.585-15.61, P = 0.041) and cytoplasmic IDO1/COX2 (HR = 2.740, 95%CI: 0.764-9.831, P = 0.038) have significantly poor OS outcomes for the CRC celecoxib subgroup. In our multivariate Cox model, high coexpression of cytoplasmic IDO1/COX2 was found to be an independent predictor of poor outcome in CRC (HR = 2.218, 95%CI: 1.011-4.48, P = 0.047) and celecoxib subgroup patients (HR = 3.210, 95%CI: 1.074-9.590, P = 0.037). CONCLUSION: Our results showed that cytoplasmic IDO1/COX2 coexpression could be used as an independent poor predictor for OS in CRC.

Circulating tumor cell status monitors the treatment responses in breast cancer patients: a meta-analysis.

Whether circulating tumor cells (CTCs) can be used as an indicator of treatment response in breast cancer (BC) needs to be clarified. We addressed this issue by a meta-analysis. PubMed, EMBase and Cochrane library databases were searched in June 2016. Effect measures were estimated as pooled risk ratio (RR), odds ratio (OR) or mean difference by fixed- or random-effect models, according to heterogeneity of included studies. In total, 50 studies with 6712 patients were recruited. Overall analysis showed that there was a significant reduction of CTC-positive rate (RR = 0.68, 95% CI: 0.61-0.76, P < 0.00001) after treatment. Subgroup analyses revealed that neoadjuvant treatment, adjuvant treatment, metastatic treatment or combination therapy could reduce the CTC-positive rate, but surgery could not; moreover, the reduction was only found in HER2+ or HER2- patients but not in the triple-negative ones. Reduction of CTC-positive rate was associated with lower probability of disease progression (OR = 0.54, 95% CI: 0.33-0.89, P = 0.01) and longer overall survival period (mean difference = 11.61 months, 95% CI: 8.63-14.59, P < 0.00001) as well as longer progression-free survival period (mean difference = 5.07 months, 95% CI: 2.70-7.44, P < 0.0001). These results demonstrate that CTC status can serve as an indicator to monitor the effectiveness of treatments and guide subsequent therapies in BC.