ABSTRACT
OBJECTIVE@#To explore the effect of hypoxia on the chemosensitivity of B-acute lymphoblastic leukemia （B-ALL） cells to Vincristine (VCR) and the mechanisms.@*METHODS@#B-ALL cells SUP-B15, Nalm-6 and RS4;11 were selected as the research objects. The cells were divided into the control group and the hypoxia mimic group (CoCl2 pretreatment). The two groups were treated with VCR at different concentrations for 24 hours, CCK-8 was used to detect cell viability, flow cytometry was used to detect cell apoptosis, and Western bolt method was used to detect hypoxia inducible factor (HIF-1α), BAX, Bcl-2 and β-actin protein expression. Quantitative real-time fluorescent PCR (qRT-PCR) was used to detect BAX and β-actin mRNA levels.@*RESULTS@#CoCl2 could simulate hypoxic environment to induce the expression of HIF-1α. The cells SUP-B15 and RS4;11 of the hypoxia mimic group were lower sensitivity to VCR as compared with the control group; the apoptosis rate of the hypoxia mimic group was lower than that of the control group after 80 nmol/L VCR treatment. The expression levels of BAX protein and mRNA in the hypoxia mimic group were lower than those of the control group, and there was no significant difference in the expression levels of Bcl-2 protein between two groups.@*CONCLUSION@#Under hypoxic conditions, HIF-1α may mediate VCR resistance in B-ALL cells by downregulating the pro-apoptotic protein BAX.
Subject(s)
Humans , Actins/pharmacology , Apoptosis , Cell Hypoxia , Hypoxia , Hypoxia-Inducible Factor 1, alpha Subunit , Proto-Oncogene Proteins c-bcl-2 , RNA, Messenger , Vincristine/pharmacology , bcl-2-Associated X Protein/pharmacologyABSTRACT
La actina de Mucor rouxii fué estudiada por: (i) extracciones con agentes caotrópicos, (ii) cromatografía de afinidad en columna de Sepharose-DNasa I. Los productos extraídos y el material unido a la DNasa I contienen un péptido principal con Mr < ou = 43 Kd; este péptido fué identificado por inmunotransferencia utilizando anticuerpos contra la actina de músculo. Finalmente, (iii) tiñendo las células con anticuerpos, antiactina y faloidina-radomina, examinamos la distribución de la actina durante el desarrollo de las hifas. Los resultados indican que: (1) la actina de Mucor rouxii presenta reacción cruzada con los anticuerpos, antiactina de músculo. La actina fúngica es similar a la actina de otros eucariontes, en cuanto a su capacidad de unirse a la desoxiribonuclease I pancreática, y (2) cambios en la distribución de la actina acompañan el desarrollo de las hifas. Sugiriendo que la actina puede estar involucrada en los procesos que acompañan el crecimiento polarizado de las células fúngicas