Beclin1 induces autophagy and its potential contributions to sensitizes SiHa cells to carboplatin therapy.
BACKGROUND
To investigate the role of Beclin1 in the relationship between autophagy and apoptosis after carboplatin treatment.


METHODS
After overexpression or partial silencing of Beclin1 in cervical cancer SiHa cells, the transfected group and the control group were treated with carboplatin for 48 hours. The expression of Beclin1 and LC3 was measured using a western blot. The ultrastructural analysis was conducted with an electron microscope. Fluorescent changes in autophagic cells were observed using reverse fluorescent microscopy. The percentage of apoptotic cells and autophagic cells and cell proliferation were assessed by flow cytometry and MTT assay.


RESULTS
Expression of LC3 and Beclin1 protein was up-regulated in overexpressed transfectants of SiHa cells. After treatment with carboplatin for 48 hours, the flow cytometric analysis indicated that the Beclin1 transfected group showed a greater increase in apoptosis and autophagic cells than did the nontransfected group. MTT assay showed that carboplatin inhibited proliferation of SiHa cells in Beclin1-overexpressed transfectant cells more than in nontransfectant cells.


CONCLUSIONS
These results suggest that autophagy and apoptosis had differential contributions to carboplatin-induced death of cervical cancer SiHa cells. Overexpression of Beclin1 in SiHa cells may enhance apoptosis signaling induced by carboplatin.
Sun
Yang
Y
Department of Obstetrics and Gynecology, West China Second Hospital, West China Center of Medical Sciences, Sichuan University, Chengdu, Sichuan, China.
Zhang
Jie
J
Peng
Zhi-lan
ZL
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis* / Q000235:genetics; D001343:Autophagy / Q000187:drug effects / Q000502:physiology; D000071186:Beclin-1; D016190:Carboplatin / Q000494:pharmacology*; D045744:Cell Line, Tumor; D005260:Female; D005434:Flow Cytometry; D020868:Gene Silencing; D006801:Humans; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis / Q000235:genetics; D014162:Transfection; D015854:Up-Regulation; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*
D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; C477012:MAP1LC3A protein, human; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D016190:Carboplatin