METTL3/YTHDF2 m6A axis promotes the malignant progression of bladder cancer by epigenetically suppressing RRAS.

The present study aimed to explore the potential roles of the methyltransferase­like 3 (METTL3)­mediated methylation of RAS related (RRAS) mRNA in the tumorigenesis and development of bladder cancer (BCa). For this purpose, the relative expression levels of METTL3 in BCa specimens and cell lines were measured using reverse transcription­quantitative PCR (RT­qPCR) and western blot analysis. The association between the METTL3 expression level and the clinical characteristics of patients with BCa was analyzed using The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interactive Analysis databases. Cellular experiments were performed to confirm the effects of METTL3 on the proliferative, migratory and invasive capacities of BCa cells. RT­qPCR, western blot analysis, methylated RNA immunoprecipitation (MeRIP)­qPCR and dual­luciferase report assays were utilized to verify the METTL3/RRAS/YTH N6­methyladenosine (m6A) RNA binding protein 2 (YTHDF2) regulatory axis in BCa. The results revealed that METTL3 expression was markedly increased in BCa specimens and cell lines, and was associated with poor clinical characteristics of patients with BCa. In vitro and in vivo assays demonstrated that the silencing of METTL3 markedly suppressed the proliferative, migratory and invasive capacities of BCa cells. MeRIP­PCR and dual­luciferase report assays indicated that METTL3 could bind to the m6A sites of RRAS mRNA and suppress the transcriptional activity of RRAS. YTHDF2 could recognize the m6A sites of RRAS and mediate RRAS degradation. On the whole, the findings of the present study reveal the pivotal role of METTL3­catalyzed m6A modification in BCa tumorigenesis and development. The change could facilitate BCa tumor growth and metastasis by suppressing RRAS expression in an m6A YTHDF2­dependent manner. Targeting the METTL3/RRAS/YTHDF2 regulatory axis may thus prove to be a promising strategy for the diagnosis and therapy of BCa.

Urinary levels of dimethoate, bisphenol A and benzo[a]pyrene in first-year students of Hohai University from different geographical regions.

BACKGROUND: The objective of this study was to detect the urinary levels of dimethoate, benzo(a) pyrene (BaP), and bisphenol A (BPA) in first-year Hohai University students with different geographic origins. METHODS: First-morning urine samples were collected from 540 healthy freshmen aged 17 to 19 years. Chemical levels were measured using ß-glucuronidase hydrolysis followed by a high-performance liquid chromatography-tandem mass spectrometry-based method. Geometric means (GMs) of these three chemicals are presented by body mass index (BMI) and location in a volume-based and creatinine-standardized way. RESULTS: GM concentrations of omethoate, BPA and 3-OHBaP were 9.47 µg/L (10.80 µg/g creatinine), 3.54 µg/L (4.04 µg/g creatinine) and 0.34 ng/L (0.39 ng/g creatinine), respectively. The GM concentration of omethoate in males was significantly higher than that in females. The individuals with a BMI higher than 23.9 had higher GM concentrations of omethoate, BPA, and 3-OHBaP. The inhabitants of Southwest China had significantly lower GM concentrations of omethoate, BPA, and 3-OHBaP than those who lived in other locations in China. CONCLUSION: The average level of environmental chemical accumulation in freshmen is lower in Southwest China and differs in youth who live in different regions. In addition, obesity is correlated with higher toxin levels in youth.

Characterization of the Akirin Gene and Its Role in the NF-κB Signaling Pathway of Sogatella furcifera.

Akirin is an essential nuclear protein involved in the regulation of NF-κB signaling pathway. In most invertebrates, Akirin regulates NF-κB-related Imd and Toll pathways, however, in Drosophila, it only controls the Imd pathway, whereas its role in NF-κB signaling pathway in other insect species is unclear. In the present study, we used white-backed planthopper Sogatella furcifera as a model to investigate the functional activity of Akirin in insects. The sequence of Akirin cDNA was extracted from transcriptome database of S. furcifera; it contained a 585 bp open reading frame (ORF) encoding a putative protein of 194 amino acids. S. furcifera Akirin (SfAkirin) had a molecular weight of about 21.69 kDa and a theoretical pI of 8.66 and included a nuclear localization signal (NLS) of five amino acid residues at the N-terminal region. Evolutionary analysis showed that SfAkirin was evolutionary closer to Akirins of such relatively distant species as crustaceans than to those of some insect orders like Diptera and Hymenoptera. Tissue-specific expression analysis showed that the SfAkirin gene was expressed in all examined tissues, with the highest expression levels detected in the testis, followed by the ovary, whereas the lowest expression was found in the head. Real-time quantitative PCR analysis showed that SfAkirin mRNA was strongly induced in response to injection of heat-inactivated Escherichia coli and Bacillus subtilis, whereas SfAkirin silencing by RNA interference significantly reduced the expression of NF-κB dependent transcription factors Dorsal and Relish after B. subtilis and E. coli challenge, respectively. Our results suggest that SfAkirin may control the immune response of S. furcifera against bacterial infection via both Imd and Toll signaling pathways.

[Expression of serum FSTL-1 in bone metastasis of prostate cancer and its clinical implication].

OBJECTIVE: To investigate the expression of follistatin-like protein 1 (FSTL-1) in bone metastasis of prostate cancer (BMPC), the correlation of serum FSTL-1 with the chronic inflammatory factor interleukin-6 (IL-6) and bone morphogenetic protein 6 (BMP6) , and the clinical application value of serum FSTL-1 in BMPC. METHODS: Using ELISA, we measured the expression levels of serum FSTL-1, IL-6, and BMP6 in 35 patients with BMPC and another 30 with benign prostatic hyperplasia (BPH) and performed correlation analysis on the data obtained. RESULTS: Compared with the BPH controls, the BMPC patients showed a significantly decreased expression of serum FSTL-1 ([34.45 ± 12.35] µg/L vs [20.23 ± 8.69] µg/L, P < 0.01) and increased levels of IL-6 ([11.21 ± 8.62] µg/L vs [23.56 ± 20.12] µg/L, P < 0.05) and BMP6 ([293.50 ± 39.72] µg/L vs [428.30 ± 178.40] µg/L, P < 0.05). There was a significant negative correlation between the level of serum FSTL-1 and those of IL-6 and BMP6 in the BMPC patients, with correlation coefficients of -0.971 and -0.972, respectively (P < 0.05). CONCLUSION: The expression of serum FSTL-1 decreases in patients with bone metastasis of prostate cancer, and it is correlated with the levels of inflammatory factor and cell transformation factor. This finding offers a novel biological marker for the development and progression of prostate cancer as well as a new biological target factor for its intervention.

[Retroperitoneal laparoscopic radical nephrectomy in the treatment of renal cancer].

OBJECTIVE: To evaluate the safety and efficacy of retroperitoneal laparoscopic radical nephrectomy in the treatment of renal cancer. METHODS: The clinical data of 53 cases who underwent retroperitoneal laparoscopic radical nephrectomy were analyzed retrospectively. RESULTS: Fifty-two cases achieved successful retroperitoneal laparoscopic radical nephrectomy, a conversion to open surgery was required in one case because of severe adhesion. The operation time was 75 min to 220 min (mean, 125 min), the blood loss was 50 ml to 420 ml (mean, 120 ml), and the postoperative hospital stay was 6 d to 12 d. Complications occurred in 4 cases. Pathological examination showed that 47 cases were of renal clear cell carcinoma, 5 of chromophobe carcinoma, and 1 of cystic renal cell carcinoma. Follow-up for 1 month to 5 years showed no tumor recurrence and metastasis. CONCLUSION: Retroperitoneal laparoscopic radical nephrectomy is a safe and effective treatment for patients with stage T1 - 2N0M0 renal cell carcinoma.

Panax notoginseng saponins preconditioning protects rat liver grafts from ischemia/reperfusion injury via an antiapoptotic pathway.

BACKGROUND: Ischemia/reperfusion (I/R) injury is a major cause of primary graft dysfunction and renders an allograft more immunogenic in orthotopic liver transplantation (OLT). Panax notoginseng saponins (PNS) has been reported to exert protective effects against I/R injury to various organs. The objective of this study is to investigate whether PNS preconditioning protects rat liver grafts from I/R injury via an antiapoptotic pathway. METHODS: Male Sprague-Dawley rats were used as donors and recipients of orthotopic liver transplantation (OLT) and were divided into PNS preconditioning group(group P) and normal saline control group (group N) randomly according to whether PNS (50 mg/kg) was injected intravenously 1 hour before liver grafts harvesting, and sham group (group S). The animals were separately killed 2, 6 and 24 hours after reperfusion. Plasma samples were collected for test of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Liver tissues were collected to detect histological changes, apoptosis and the expression of TNF-alpha, Bcl-2 and Caspase-3 mRNA. RESULTS: The serum levels of ALT and AST and the apoptosis index (AI) of liver tissue in group P were lower than in group N significantly 2, 6 and 24 hours after reperfusion. Compared with group N, the expression of TNF-alpha and Caspase-3 mRNA was reduced significantly in group P 2 and 6 hours after reperfusion and the expression of Bcl-2 mRNA was enhanced significantly in group P 6 and 24 hours after reperfusion. CONCLUSIONS: PNS preconditioning protects liver grafts from I/R injury effectively in rat OLT via an antiapoptotic pathway. The antiapoptotic mechanisms of PNS may include inhibiting the expression of TNF-alpha and Caspase-3 and enhancing the expression of Bcl-2.