The interaction between m⁶A-methylated RNA and chromatin modification remains largely unknown. We found that targeted inhibition of bromodomain-containing protein 4 (BRD4) by siRNA or its inhibitor (JQ1) significantly decreases mRNA m⁶A levels and suppresses the malignancy of breast cancer (BC) cells via increased expression of demethylase AlkB homolog 5 (ALKBH5). Mechanistically, inhibition of BRD4 increases the mRNA stability of ALKBH5 via enhanced binding between its 3' untranslated regions (3'UTRs) with RNA-binding protein RALY. Further, BRD4 serves as a scaffold for ubiquitin enzymes tripartite motif containing-21 (TRIM21) and ALKBH5, resulting in the ubiquitination and degradation of ALKBH5 protein. JQ1-increased ALKBH5 then demethylates mRNA of extra spindle pole bodies like 1 (ESPL1) and reduces binding between ESPL1 mRNA and m⁶A reader insulin like growth factor 2 mRNA binding protein 3 (IGF2BP3), leading to decay of ESPL1 mRNA. Animal and clinical studies confirm a critical role of BRD4/ALKBH5/ESPL1 pathway in BC progression. Further, our study sheds light on the crosstalks between histone modification and RNA methylation.

OBJECTIVE: To investigate the role of MTBP in regulating the migration and invasion of human prostate cancer cells. METHODS: The baseline expressions of MTBP in 3 different human prostate cancer cells lines (22RV1, DU145 and Lncap) were detected using Western blotting. The cells were transfected with a small interfering RNA (siRNA) for MTBP knockdown or MTBP plasmid for MTBP overexpression, and 48 h later, the cells were examined for MTBP expression with Western blotting; the changes in the migration abilities of the cells were evaluated using wound healing assay and Transwell assay, and the cell invasiveness was assessed using Matrigel Transwell assay. The expression of E-cadherin protein, a marker of epithelial mesenchymal transition (EMT), was detected using Western blotting. RESULTS: MTBP expression was the highest in DU145 cells followed by Lncap cells, and was the lowest in 22RV1 cells, indicating a positive correlation of MTBP expression with the level of malignancy of human prostate cancer cells. Transfection of the cells with siRNA or MTBP plasmids efficiently lowered or enhanced the expressions of MTBP in human prostate cancer cells. Wound healing assay showed that inhibition of MTBP expression decreased the migration ability of the prostate cancer cells, and MTBP overexpression significantly promoted the migration of the cells ( < 0.01). Transwell assay showed that MTBP knockdown significantly lowered the migration and invasion ability of the cells, while MTBP overexpression markedly increased the number of migrating and invading cells ( < 0.01); Western blotting results showed that MTBP knockdown increased the expression of E-cadherin protein, and MTBP overexpression decreased E-cadherin expression in the prostate cancer cells. CONCLUSIONS MTBP overexpression promotes the migration and invasion of human prostate cancer cells possibly relation to the induction of EMT.
Antigens, CD ; metabolism ; Cadherins ; metabolism ; Carrier Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Cell Movement ; Epithelial-Mesenchymal Transition ; Gene Expression Regulation, Neoplastic ; Gene Knockdown Techniques ; Humans ; Male ; Neoplasm Invasiveness ; Prostatic Neoplasms ; metabolism ; pathology ; RNA, Small Interfering ; Transfection

OBJECTIVETo investigate the protective effect of bone marrow mesenchymal stem cells (BMSCs)-derived exosomesagainst testicular ischemia-reperfusion injury (IRI) in rats.

METHODSRat BMSCs were isolated, cultured and identified in theprimary culture. The exosomes were extracted from the BMSCs and characterized using nanoparticle tracking analysis, transmission electron microscopy, and Western blotting. Twenty-four healthy male SD rats were randomly divided into shamoperation group, testicular IRI with saline treatment group and IRI with exosome treatment group. The contralateral testes ofthe rats were collected for pathological observation, aseessment of superoxide dismutase (SOD) and malondialdehyde (MDA), and detection of HMGB1, caspases-3 and cleaved caspase-3 expressions using Western blotting.

RESULTSWe successfullyobtained exosomes from rat BMSCs. Testicular IRI significantly impaired testicular spermatogenesis, which was markedlyimproved by treatment with the exosomes ( < 0.05). Testicular IRI also caused significant increase in the protein expression ofHMGB1, caspase-3 and cleaved caspase-3 in the testicular tissue, and treatment with the exosomes obviously amelioratedthese changes ( < 0.05).

CONCLUSIONSBMSCs-derived exosomes protects against testicular IRI due to the anti-oxidant, antiinflammatory and anti-apoptosis activities of the exosomes.

Objective To investigate the influence of application of local anesthesia with lidocaine on bronchial lavage fluid (BLF) pseudomonas aeruginosa culture and drug sensitivity in cases with lung infection .Methods Two hundred and seventy speci-men of BLF were collected from 135 patients with infection of lung .And BLF were collected directly from right-broncho in control group ,and from left-broncho in lidocaine group .The outcome of pseudomonas aeruginosa culture and drug sensitivity were com-pared in the two groups .Results Fourty-two cases were postitive in BLF pseudomonas aeruginosa culture in the control group ,and 40 cases were postitive in lidocaine group .The positive rates were 31 .11% and 29 .63% ,respectively .There were no significance between the two groups (P<0 .001) .Compared with the control group ,the sensitive strains of pseudomonas aeruginosa were obvi-ously less and the drug tolerance strains were much more in lidocaine group for Ciprofloxacin and Levofloxacin (P<0 .05) .Howev-er ,there were no influence for drugs such as Piperacillin/Tazobactam and Ceftazidime ,etc .Conclusion 2% lidocaine has no influ-ence on the outcome of BLF pseudomonas aeruginosa culture .But it may reduce the drug sensitivity of Ciprofloxacin and Levofloxa-cin in cases with infection of lung .