Xiaobing Niu

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.

Novel methods for the diagnosis and treatment of ejaculatory duct obstruction

Study Type – Therapy (case series)

Hsa-miR-146a-5p modulates androgen-independent prostate cancer cells apoptosis by targeting ROCK1

MicroRNAs (miRNAs) have been demonstrated playing important roles in the procession of prostate cancer cells transformation from androgen‐dependence to androgen‐independence.

Characterization of lactoferrin receptor on human spermatozoa

Lactoferrin (LF) is abundant in human seminal plasma and on sperm surfaces. However, lactoferrin receptor (LFR) on human spermatozoa has not yet been reported. To study the expression, localization and characteristics of LFR on human spermatozoa, different experimental approaches were applied: LFR gene was amplified from a human testis cDNA library and recombinant LFR (rLFR) protein was produced in the expression vector Escherichia coli BL21 (DE3); human sperm membrane proteins were extracted and analysed via Western blot; the binding of LF to LFR was investigated by Far-Western blot, immunoprecipitation and autoradiography analysis and the localization of LFR on sperm surfaces was detected using immunofluorescence. LFR gene was amplified from a human testis cDNA library and the molecular weight of rLFR was 34kDa. The native LFR on human spermatozoa was a 136-kDa tetramer which was anchored to the sperm head and mid-piece through glycophosphatidylinositol. LF could bind to LFR competitively in vitro. As far as is known, this study has elucidated for the first time that LFR was expressed at the testis level, was anchored to the sperm membrane by glycophosphatidylinositol during spermatogenesis. LFR may play important roles through binding to and mediating LF.

AB215. Variants in the SRD5A2 gene are associated with quality of semen

Spermatogenesis and sperm maturation are androgen-dependent processes. Steroid 5α-reductase (SRD5A) is a key enzyme converting testosterone into the more active metabolite, dihydrotestosterone (DHT). We aimed to investigate the association between the genetic variants of SRD5A2 (rs4952197, rs2268797, rs13395648, rs523349 and rs632148) and semen quality. Variant genotyping and semen analysis was performed in 708 males with definite idiopathic infertility by TaqMan SNP genotyping assays and computer-assisted semen analysis, respectively. It was found that the rs13395648 TC genotype was associated with a significantly lower semen volume compared with the TT genotype (P=0.016). The same trend was found between the combination of the TC and CC genotypes and the TT genotype (P=0.020). With regard to variant rs632148, subjects with the GC genotype had significantly lower sperm motility in comparison to those with the GG genotype (P=0.029). The sperm motility between the combination of the GC and CC genotypes and the GC genotype was also significantly different (P=0.033). These findings indicate that genetic variants in the SRD5A2 gene may be associated with semen quality.

The value of epididymal protease inhibitor in differential diagnosis between obstructive azoospermia and non-obstructive azoospermia

There are no efficient and noninvasive clinical tests to distinguish between obstructive azoospermia (OA) and non‐obstructive azoospermia (NOA). Epididymal protease inhibitor (Eppin) protein is secreted specifically by testes and epididymides in male reproductive system. It does not exist in seminal plasma of patients with OA in theory. The seminal plasma from 40 normal men and 46 azoospermic patients was detected via Western blot for investigating the presence and characteristics of Eppin protein to distinguish between OA and NOA. The cases were diagnosed as NOA whether Eppin in seminal plasma was positive via Western blot analysis. The cases were diagnosed as OA when samples were Eppin‐negative. Additionally, percutaneous epididymal sperm aspiration (PESA) and percutaneous testicular sperm aspiration (PTSA) were performed on these patients at the same time as the diagnostic criteria to compare with Western blot analysis. Eppin detection in seminal plasma showed similar effectivity with PESA/PTSA in differential diagnosis between OA and NOA. Compared with PESA/PTSA, Eppin detection is a new, efficient and noninvasive method which has good clinical application.