Zengjun Wang

MiR-146a suppresses tumor growth and progression by targeting EGFR pathway and in a p-ERK-dependent manner in castration-resistant prostate cancer†‡

Castration‐resistant prostate cancer (CRPC) is a leading cause of cancer‐related deaths in elder men. This disease has limited therapeutic options and poor prognosis as the underlying molecular mechanisms are not clearly understood. Given the emerging roles of microRNA (miRNA) as a key regulator, we postulated that miRNA may play a significant role in CRPC formation.

Proteomic characteristics of human sperm cryopreservation

Human sperm cryopreservation in assisted reproductive technology is the only proven method that enables infertile men to father their own children. However, freezing and thawing reduces spermatozoon motility, viability, and fertilizing ability. An association between dysfunctional spermatozoa due to cryoinjury and protein changes has not been established. We investigated through proteomic analysis the differential protein characteristics between freeze‐thawed and fresh sperm samples obtained from nine normozoospermic donors. Twenty‐seven proteins differed in abundance between the two groups, and results were verified for four proteins via Western blot and immunofluorescent staining. These proteins are putatively involved in sperm motility, viability, acrosomal integrity, ATP and isocitrate content, mitochondrial membrane potential, capacitation, acrosome reaction, and intracellular calcium concentration. These marked differences suggest that dysfunctional spermatozoon after cryopreservation may be due to protein degradation and protein phosphorylation.

Genetic polymorphisms of cytochrome P450 and glutathione S-transferase associated with antituberculosis drug-induced hepatotoxicity in Chinese tuberculosis patients.

This study was designed to investigate the association of genetic polymorphisms of cytochrome P450 subtype 2E1 (CYP2E1) and glutathione S-transferase mu 1 (GSTM1) with susceptibility to antituberculosis drug-induced hepatotoxicity (ADIH) in Chinese tuberculosis patients. All patients were treated with a combination of isoniazid, rifampicin, pyrazinamide and ethambutol. Genomic DNA from 104 patients with ADIH and 111 without ADIH was analysed for the frequency of CYP2E1 RsaI and GSTM1 RsaI genotypes by polymerase chain reaction and restriction fragment length polymorphism. The association of polymorphisms with susceptibility to ADIH was calculated using the χ2-test and logistic regression analysis. The CYP2E1 RsaI polymorphisms were significantly associated with ADIH and the c1/c1 genotype was an independent risk factor for ADIH. Compared with the GSTM1 RsaI present genotype, the GSTM1 RsaI null genotype tended to increase susceptibility to ADIH, but the association with ADIH was not significant. The results indicate that CYP2E1 RsaI genotype c1/c1 is a potential risk factor for ADIH in the Chinese population. The tendency of the GSTM1 RsaI null genotype to increase susceptibility to ADIH needs further study.

Functional promoter -94 ins/del ATTG polymorphism in NFKB1 gene is associated with bladder cancer risk in a Chinese population.

Background A functional -94 insertion/deletion polymorphism (rs28362491) in the promoter of the NFKB1 gene was reported to influence NFKB1 expression and confer susceptibility to different types of cancer. This study aims to determine whether the polymorphism is associated with risk of bladder cancer. Materials and methods TaqMan assay was used to determine genotype among 609 cases and 640 controls in a Chinese population. Logistic regression was used to assess the association between the polymorphism and bladder cancer risk, and quantitative real-time polymerase chain reaction was used to determine NFKB1 mRNA expression. Results Compared with the ins/ins/ins/del genotypes, the del/del genotype was associated with a significantly increased risk of bladder cancer [adjusted odd ratio (OR)  = 1.92, 95% confidence interval (CI)  = 1.42–2.59]. The increased risk was more prominent among subjects over 65 years old (OR  = 2.37, 95% CI  = 1.52–3.70), male subjects (OR  = 1.97, 95% CI = 1.40–2.79) and subjects with self-reported family history of cancer (OR  = 3.59, 95% CI  = 1.19–10.9). Furthermore, the polymorphism was associated with a higher risk of developing non-muscle invasive bladder cancer (OR  = 2.07, 95% CI  = 1.51–2.85), grade 1 bladder cancer (OR  = 2.40, 95% CI  = 1.68–3.43), single tumor bladder cancer (OR  = 2.04, 95% CI  = 1.48–2.82) and smaller tumor size bladder cancer (OR  = 2.10, 95% CI  = 1.51–2.92). The expression of NFKB1 mRNA in bladder cancer tissues with homozygous insertion genotype was higher than that with deletion allele. Conclusions In conclusion, the -94 ins/del ATTG polymorphism in NFKB1 promoter may contribute to the etiology of bladder cancer in the Chinese population.

H19-derived miR-675 contributes to bladder cancer cell proliferation by regulating p53 activation.

Long noncoding RNA 19 (H19) has been shown to promote bladder cancer cell proliferation and metastasis. However, little is known about how miR-675, mature product of H19, contributes to bladder cancer cell proliferation. In this study, we first evaluated the expression of miR-675 in bladder cancer tissues by quantitative real-time PCR (qRT-PCR) and defined its biological functions by flow cytometry and Western blotting. We found that miR-675 expression levels were remarkably increased in bladder cancer tissues as compared with adjacent noncancerous tissues or normal bladder tissue from health donors; moreover, enhanced miR-675 expression was also observed in bladder cancer cell lines. Ectopic expression of H19 significantly increased bladder cancer cell proliferation and miR-675 expression in vitro. Furthermore, overexpression of miR-675 promoted bladder cancer cell proliferation, while suppression of miR-675 induced G1 phase cell cycle arrest and promoted cell apoptosis. Western blotting analysis further identified that miR-675 inhibited p53 activation, decreased the ratio of Bax/Bcl-2 and cyclin D1 expression in bladder cancer cells; those effects may result in the abnormal proliferation of bladder cancer cells. In conclusion, abnormal enhanced miR-675 expression increases bladder cancer growth by regulating p53 activation, and thus may be helpful in the development of effective treatment strategies for bladder cancer.

Metadherin is a novel prognostic marker for bladder cancer progression and overall patient survival.

Aim:  Metadherin (MTDH) is a potential oncogene in tumor development and is highly expressed in various types of human cancers. However, there has been no report on the role of MTDH in bladder cancer. Our aim was to investigate the expression pattern of MTDH in bladder tissue at different clinic pathological stages and evaluate the potential of MTDH as a biomarker of bladder cancer.

Novel methods for the diagnosis and treatment of ejaculatory duct obstruction

Study Type – Therapy (case series)

Galangin inhibits cell invasion by suppressing the epithelial-mesenchymal transition and inducing apoptosis in renal cell carcinoma

Galangin, a flavonoid extracted from the root of the Alpinia officinarum Hence, has been shown to have anticancer properties against several types of cancer cells. However, the influence of galangin on human renal cancer cells remains to be elucidated. In the present study, proliferation of 786-0 and Caki-1 cells was suppressed following exposure to various doses of galangin. Cell invasion and wound healing assays were used to observe the effect of galangin on invasion and migration. The results demonstrated that Galangin inhibited cell invasion by suppressing the epithelial mesenchymal transition (EMT), with an increase in the expression of E-cadherin and decreased expression levels of N-cadherin and vimentin. The apoptosis induced by galangin was analyzed by flow cytometry. The results revealed that galangin induced apoptosis in a dose-dependent manner. The accumulation of reactive oxygen species (ROS) is an important contributing factor for the apoptosis of various types of cancer cell. The dichlorofluorescein-diacetate method was used to determine the level of ROS. Galangin induced the accumulation of intracellular ROS and malondialdehyde, and decreased the activities of total antioxidant and superoxide dismutase in renal cell carcinoma cells. Galangin exerted an antiproliferative effect and inhibited renal cell carcinoma invasion by suppressing the EMT. This treatment also induced apoptosis, accompanied by the production of ROS. Therefore, the present data suggested that galangin may have beneficial effects by preventing renal cell carcinoma growth, inhibiting cell invasion via the EMT and inducing cell apoptosis.

Association of the Glutathione S-Transferase M1, T1 Polymorphisms with Cancer: Evidence from a Meta-Analysis

Background Glutathione S-transferases (GSTs) are a family of multifunctional enzymes that are involved in the metabolism of many xenobiotics, including a wide range of environmental carcinogens. While the null genotypes in GSTM1 and GSTT1 have been implicated in tumorigenesis, it remains inconsistent and inconclusive. Herein, we aimed to assess the possible associations of the GSTM1 and GSTT1 null genotype in cancer risks. Methods A meta-analysis based on 506 case-control studies was performed. Odds ratios (OR) with corresponding 95% confidence intervals (CIs) were used to assess the association. Results The null genotypes of GSTM1 and GSTT1 polymorphisms were associated with a significantly increased risk in cancer (for GSTM1: OR = 1.17; 95%CI = 1.14–1.21; for GSTT1: OR = 1.16; 95%CI = 1.11–1.21, respectively). When the analysis was performed based on their smoking history, the risk associated of GSTM1 null and GSTT1 null genotypes with cancer is further increased (for GSTM1: OR = 2.66; 95%CI = 2.19–3.24; for GSTT1: OR = 2.46; 95%CI = 1.83–3.32, respectively). Conclusions These findings indicate that GSTM1 and GSTT1 polymorphisms may play critical roles in the development of cancer, especially in smokers.

The Use of Anti-VDAC2 Antibody for the Combined Assessment of Human Sperm Acrosome Integrity and Ionophore A23187-Induced Acrosome Reaction

Voltage-dependent anion channel (VDAC) is mainly located in the mitochondrial outer membrane and participates in many biological processes. In mammals, three VDAC subtypes (VDAC1, 2 and 3) have been identified. Although VDAC has been extensively studied in various tissues and cells, there is little knowledge about the distribution and function of VDAC in male mammalian reproductive system. Several studies have demonstrated that VDAC exists in mammalian spermatozoa and is implicated in spermatogenesis, sperm maturation, motility and fertilization. However, there is no knowledge about the respective localization and function of three VDAC subtypes in human spermatozoa. In this study, we focused on the presence of VDAC2 in human spermatozoa and its possible role in the acrosomal integrity and acrosome reaction using specific anti-VDAC2 monoclonal antibody for the first time. The results exhibited that native VDAC2 existed in the membrane components of human spermatozoa. The co-incubation of spermatozoa with anti-VDAC2 antibody did not affect the acrosomal integrity and acrosome reaction, but inhibited ionophore A23187-induced intracellular Ca2+ increase. Our study suggested that VDAC2 was located in the acrosomal membrane or plasma membrane of human spermatozoa, and played putative roles in sperm functions through mediating Ca2+ transmembrane transport.