Bioinformatics analysis identifies potential hub genes and crucial pathways in the pathogenesis of asthenozoospermia.

BACKGROUND: Asthenozoospermia is a troublesome disease experienced by men in their reproductive years, but its exact etiology remains unclear. To address this problem, this study aims to identify the hub genes and crucial pathways in asthenozoospermia. METHODS: We screened two Gene Expression Omnibus (GEO) datasets (GSE92578 and GSE22331) to extract the differentially expressed genes (DEGs) between normozoospermic and asthenozoospermic men using the "Limma" package. Gene enrichment analyses of the DEGs were conducted using the "clusterProfiler" R package. The protein-protein interaction (PPI) network was then established using the STRING database. A miRNA-transcription factor-gene network was constructed based on the predicted results of hub genes using the RegNetwork database. The expression of four hub genes in asthenozoospermia and normal samples were verified using quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting. RESULTS: We identified 271 DEGs, which included 218 upregulated and 53 downregulated in two asthenozoospermia datasets. These DEGs were observed to be markedly enriched in pathways with cell growth and embryonic organ development, phospholipase D signaling pathway, cGMP-PKG signaling pathway, and Wnt signaling pathway. The most significant genes were identified, including COPS7A, CUL3, KLHL7, NEDD4. We then constructed regulatory networks of these genes, miRNAs, and transcription factors. Finally, we found that the COPS7A was significantly upregulated in patients with asthenozoospermia, but CUL3, KLHL7 and NEDD4 were significantly downregulated compared with normal samples. CONCLUSION: We applied bioinformatics methods to analyze the DEGs of asthenozoospermia based on the GEO database and identified the novel crucial genes and pathways in this disease. Our findings may provide novel insights into asthenozoospermia and identify new clues for the potential treatment of this disease.

Cigarette smoke supports stemness and epithelial-mesenchymal transition in bladder cancer stem cells through SHH signaling.

Cancer stem cells (CSCs) are essential in every step of tumorigenesis and progression. As an important process in cancer development, epithelial-mesenchymal transition (EMT) has been reported to promote stem-like cells. Bladder cancer is one of the most common cancers in the urinary tract, and cigarette smoke (CS) is a preventable risk factor. In the present study, we tested the hypothesis that CS could promote stemness and EMT in bladder cancer. Bladder cancer UM-UC-3 and EJ cell lines were maintained in serum-free medium to grow as tumor spheres, characteristic of CSCs. Results demonstrated that CS enhanced tumor sphere formation capacity, upregulated expression of CSC markers, increased the proportion of the CD44+ cell population, and promoted EMT. Mechanistically, the Sonic Hedgehog (SHH) pathway regulated CS-triggered EMT and stemness. More importantly, among bladder cancer patients, smokers harbored higher levels of CSC markers and proteins for SHH signaling than non-smokers. Collectively, findings in this study highlight the critical role of CS in the stemness and EMT of bladder cancer. Smoking cessation and intervening in the SHH pathway may both be strategies to prevent bladder cancer.

Nanog mediates tobacco smoke-induced enhancement of renal cancer stem cell properties.

Nanog plays an important role in the regulation of cancer stem cells (CSCs) which participate in tumorgenesis and progression. In renal cancer, tobacco smoke (TS) is considered a major risk factor. However, the molecular mechanism by which TS induces the development of renal CSC properties remains largely unknown. In this study, we showed that the level of Nanog was elevated in renal cell carcinoma (RCC) patients with a smoking history, and that Nanog overexpression promoted the traits of CSCs in renal cancer. We further demonstrated that a 8-week exposure of TS enhanced the formation of renal tumorspheres, increased the population of CD133-positive cells, and stimulated the expression of Nanog and CSC markers. In addition, TS was found to play a role in accelerating the cell growth transition from G1 to S phase in renal CSCs. Finally, we demonstrated that the TS-induced effects in renal CSCs could be reversed through the downregulation of Nanog. Our results suggested that Nanog plays a role in mediating TS-induced renal CSC properties. This study may provide new insights into the molecular mechanism of TS-related renal tumorigenesis, which can contribute to the future development of therapeutics for renal cancer.

Sonic hedgehog pathway mediates genistein inhibition of renal cancer stem cells.

Cancer stem cells (CSCs) have been implicated in the genesis, progression and recurrence of renal cancer. The sonic hedgehog (Shh) pathway serves a critical role in maintaining the stemness of CSCs. Genistein, a major isoflavone component extracted from soybeans and soy products, has been demonstrated to possess anticancer activity. However, the effects of genistein on renal CSCs and its underlying mechanisms remain to be fully elucidated. The aim of the present study was to investigate the role of the Shh pathway in genistein inhibition of renal CSCs. The results of the present study demonstrated that expression levels of renal CSC markers were markedly upregulated in the sphere-forming cells, which were isolated and enriched from 786-O and ACHN cells in a tumor sphere formation assay, and more cells were arrested at the G0/G1 phase instead of the S1 phase compared with the adherent cells. Furthermore, the present study demonstrated that genistein could effectively diminish the activity of renal CSCs by suppressing tumor sphere formation, decreasing renal CSCs markers, inhibiting proliferation and inducing apoptosis. Additionally, the downregulation of Shh pathway activity could inhibit renal CSCs. Genistein exhibited an inhibitory effect on renal CSCs by attenuating the activation of the Shh pathway. In conclusion, the results illustrated the role of the Shh pathway in regulating renal CSC traits and the intervention of renal CSCs by genistein, which could provide novel insights into the molecular mechanisms of renal CSC intervention.

(­)­Epigallocatechin­3­gallate inhibits bladder cancer stem cells via suppression of sonic hedgehog pathway.

Cancer stem cells (CSCs) are associated with the occurrence and metastasis of human malignant tumors, and targeting CSCs is an important strategy for cancer prevention and overcoming drug resistance. (­)­Epigallocatechin­3­gallate (EGCG), a bioactive polyphenol from green tea, has been studied extensively for its beneficial effects on various tumors including bladder cancer. However, the mechanism underlying the effect of EGCG on bladder CSCs remains poorly understood. Here, the authors investigated the expression of bladder CSCs markers including cluster of differentiation (CD)44, CD133, Oct4, ALDH1A1 and Nanog, and their role in the effect of EGCG on bladder CSCs. EGCG inhibited bladder cancer tumorspheres, downregulated stem cell markers, suppressed the expression of proliferation­associated proteins in and promoted the apoptosis of bladder CSCs. The effect of EGCG was mediated by the sonic hedgehog signaling pathway, and upregulation of sonic hedgehog signaling pathway components attenuated the suppressive effects of EGCG. Taken together, the results indicated that EGCG could be an important natural compound against bladder CSCs and provide new insights into the effective molecular targeting of bladder CSCs.

Reduced Graphene Oxide Nanohybrid-Assembled Microneedles as Mini-Invasive Electrodes for Real-Time Transdermal Biosensing.

A variety of nanomaterial-based biosensors have been developed to sensitively detect biomolecules in vitro, yet limited success has been achieved in real-time sensing in vivo. The application of microneedles (MN) may offer a solution for painless and minimally-invasive transdermal biosensing. However, integration of nanostructural materials on microneedle surface as transdermal electrodes remains challenging in applications. Here, a transdermal H2 O2 electrochemical biosensor based on MNs integrated with nanohybrid consisting of reduced graphene oxide and Pt nanoparticles (Pt/rGO) is developed. The Pt/rGO significantly improves the detection sensitivity of the MN electrode, while the MNs are utilized as a painless transdermal tool to access the in vivo environment. The Pt/rGO nanostructures are protected by a water-soluble polymer layer to avoid mechanical destruction during the MN skin insertion process. The polymer layer can readily be dissolved by the interstitial fluid and exposes the Pt/rGO on MNs for biosensing in vivo. The applications of the Pt/rGO-integrated MNs for in situ and real-time sensing of H2 O2 in vivo are demonstrated both on pigskin and living mice. This work offers a unique real-time transdermal biosensing system, which is a promising tool for sensing in vivo with high sensitivity but in a minimally-invasive manner.

Modulation of autophagy in the protective effect of resveratrol on PM2.5-induced pulmonary oxidative injury in mice.

Ambient fine particulate matter (PM2.5) is capable of inducing pulmonary oxidative injury. Autophagy maintains basal cellular homeostasis and plays a critical role in the pathogenesis of lung diseases. Resveratrol, a natural polyphenol, is an effective antioxidant agent against particulate matter (PM)-induced injuries. The current study was designed to investigate whether resveratrol can regulate autophagy in the process of PM2.5-mediated pulmonary oxidative injury. In the mice model of PM2.5 exposure, we found that PM2.5 increased the contents of malondialdehyde (MDA) and nitric oxide (NO) while decreased the expression of nuclear factor erythroid-2-related factor 2 in the lungs. The levels of 8-hydroxydeoxyguanosine and inflammatory cytokines were increased following PM2.5 exposure. Histological analysis of the lungs revealed inflammatory change in PM2.5 group. Meanwhile, PM2.5 triggered autophagy, as evidenced by the elevated expression of microtubule-associated proteins light chain 3II, Beclin1 and p62. Transmission electron microscopy images showed that autophagosomes accumulated in the lungs after PM2.5 exposure. Furthermore, resveratrol intervention suppressed autophagy and attenuated the oxidative injury resulting from PM2.5 exposure. Our findings provided a valuable insight into the underlying mechanism for the protective effects of resveratrol against PM2.5-induced lung injury, which involves suppression of the autophagic process.

Benzidine Induces Epithelial-Mesenchymal Transition of Human Bladder Cancer Cells through Activation of ERK5 Pathway.

Benzidine, a known carcinogen, is closely associated with the development of bladder cancer (BC). Epithelial-mesenchymal transition (EMT) is a critical pathophysiological process in BC progression. The underlying molecular mechanisms of mitogen-activated protein kinase (MAPK) pathway, especially extracellular regulated protein kinases 5 (ERK5), in regulating benzidine-induced EMT remains unclarified. Hence, two human bladder cell lines, T24 and EJ, were utilized in our study. Briefly, cell migration was assessed by wound healing assay, and cell invasion was determined by Transwell assay. Quantitative PCR and western blot were utilized to determine both gene expressions as well as protein levels of EMT and MAPK, respectively. Small interfering RNA (siRNA) was transfected to further determine ERK5 function. As a result, the migration and invasion abilities were enhanced, epithelial marker expression was decreased while mesenchymal marker expression was increased in human BC cell lines. Meanwhile, benzidine administration led to activation of ERK5 and activator protein 1 (AP-1) proteins, without effective stimulation of the Jun N-terminal kinase (JNK) or p38 pathways. Moreover, Benzidine-induced EMT and ERK5 activation were completely suppressed by XMD8-92 and siRNAs specific to ERK5. Of note, ERK1/2 was activated in benzidine-treated T24 cells, while benzidine-induced EMT could not be reversed by U0126, an ERK1/2 inhibitor, as indicated by further study. Collectively, our findings revealed that ERK5-mediated EMT was critically involved in benzidine-correlated BC progression, indicating the therapeutic significance of ERK5 in benzidine-related BC.