We used the Nanshan 1 m telescope of Xinjiang Astronomical Observatory to investigate variable stars in the region of NGC 1245. We detected 55 variable stars in the field of view, 42 of them are newly discovered: six ...We used the Nanshan 1 m telescope of Xinjiang Astronomical Observatory to investigate variable stars in the region of NGC 1245. We detected 55 variable stars in the field of view, 42 of them are newly discovered: six binaries, 22 pulsating stars, 14 unclassified variables. We discussed the physical properties and classifications of the variable stars through their light curves. The cross-matching with the members catalog of NGC 1245 suggests that 10 variable stars are identified as probable cluster members, which including one EW type binary, eight δ Scuti stars, and an unknown type variable star. Since the difference of the members catalog of the cluster and the limitations of the instrument, there are some huge differences in the variable list of NGC 1245 compared with the previous work.展开更多
BRCA2,a clinical prognostic factor,is significantly up-regulated in mRNA level,while its protein expression is often decreased in sporadic breast cancer.However,how BRCA2 protein expressions are suppressed in these tu...BRCA2,a clinical prognostic factor,is significantly up-regulated in mRNA level,while its protein expression is often decreased in sporadic breast cancer.However,how BRCA2 protein expressions are suppressed in these tumors remains unknown.In this study,we demonstrated that miR-1245 directly suppressed BRCA23′-UTR and translation,impaired homologous recombination(HR)-mediated repair,reduced DNA damage-induced Rad51 nuclear foci,and rendered cells hypersensitive to g-irradiation(IR),ul-timately inducing high chromosomal abnormalities in normal breast cells and breast cancer cells.Conversely,inhibiting miR-1245 in breast cancer cells enhanced BRCA2 levels and induced resistance to IR.Furthermore,we demonstrated that c-myc up-regulated miR-1245 expression via direct binding to the miR-1245 promoter,which led to down-regulation of BRCA2 and reduction in HR efficiency.Significantly,miR-1245 levels in primary breast tumors correlated with c-myc overexpression and BRCA2 suppression.These findings uncover a BRCA2 regulatory and signaling pathway in sporadic breast cancer and support a functionally and clinically relevant epigenetic mechanism in cancer pathogenesis.展开更多
基金This work is supported by the National Natural Science Foundation of China(Grant Nos.11763007,11863005,and U2031204)the program of Tianshan Youth(Nos.2017Q091,and 2017Q014)+1 种基金the Youth Innovation Promotion Association CAS(Grant No.2018080)the Natural Science Foundation of Xinjiang(No.2021D01C075).
文摘We used the Nanshan 1 m telescope of Xinjiang Astronomical Observatory to investigate variable stars in the region of NGC 1245. We detected 55 variable stars in the field of view, 42 of them are newly discovered: six binaries, 22 pulsating stars, 14 unclassified variables. We discussed the physical properties and classifications of the variable stars through their light curves. The cross-matching with the members catalog of NGC 1245 suggests that 10 variable stars are identified as probable cluster members, which including one EW type binary, eight δ Scuti stars, and an unknown type variable star. Since the difference of the members catalog of the cluster and the limitations of the instrument, there are some huge differences in the variable list of NGC 1245 compared with the previous work.
基金supported by the National Natural Science Foundation of China (Nos.81071647,81071762,30872930,81071780,81030048,30870963,and 30831160517)the Science and Technology Department of Guangdong Province,China (No.S2011020002757)the Fundamental Research Funds for the Central Universities (No.10ykzd03).
文摘BRCA2,a clinical prognostic factor,is significantly up-regulated in mRNA level,while its protein expression is often decreased in sporadic breast cancer.However,how BRCA2 protein expressions are suppressed in these tumors remains unknown.In this study,we demonstrated that miR-1245 directly suppressed BRCA23′-UTR and translation,impaired homologous recombination(HR)-mediated repair,reduced DNA damage-induced Rad51 nuclear foci,and rendered cells hypersensitive to g-irradiation(IR),ul-timately inducing high chromosomal abnormalities in normal breast cells and breast cancer cells.Conversely,inhibiting miR-1245 in breast cancer cells enhanced BRCA2 levels and induced resistance to IR.Furthermore,we demonstrated that c-myc up-regulated miR-1245 expression via direct binding to the miR-1245 promoter,which led to down-regulation of BRCA2 and reduction in HR efficiency.Significantly,miR-1245 levels in primary breast tumors correlated with c-myc overexpression and BRCA2 suppression.These findings uncover a BRCA2 regulatory and signaling pathway in sporadic breast cancer and support a functionally and clinically relevant epigenetic mechanism in cancer pathogenesis.
