title: Ginkgetin induces apoptosis in 786-O cell lineviasuppression of JAK2-STAT3 pathway.
abstract: OBJECTIVE
  Renal cell carcinoma (RCC) is insensitive to conventional chemotherapy. Ginkgetin effectively treats several carcinoma cells. However, little is known about effects of Ginkgetin on RCC. In the present study, using 786-O cells, we evaluate whether Ginkgetin exerts anticancer effects against RCC.
  
  
  METHODS
  786-O cells suspended in the medium containing Ginkgetin were cultured for 24 hr to 72 hr, and then MTT assay was used to study cytotoxic effect of Ginkgetin. Apoptosis in 786-O was measured by an FITC Annexin apoptosis detection kit. Protein expression was detected by Western blotting. 786-O cells with active Janus kinase 2 (JAK2)-Signal transducer and activator of transcription 3 (STAT3) were prepared by stimulant of interleukin-6 (IL-6), whereas 786-O cells with deactivated STAT3 were produced by small interfering RNA (siRNA) STAT3.
  
  
  RESULTS
  Ginkgetin suppressed the growth of 786-O in dose and time-dependent manners with IC50values of 7.23 μM. Ginkgetin induced apoptosis of 786-O cells and increased the levels of caspase-8, caspase-9, and caspase-3. Additionally, Ginkgetin treated 786-O cells showed decreased levels of JAK2 and phosphorylated-STAT3 whether or not IL-6 was pretreated. Interestingly, pretreatment of siRNA STAT3 exerted inhibitory effects on the growth of 786-O cells, and the observation could be further reinforced after the Ginkgetin treatment.
  
  
  CONCLUSIONS
  Our results indicate Ginkgetin possesses obvious inhibitory effects on the proliferation of 786-O, and this effect is probably due to its inhibition of JAK2/STAT3 pathway. Our findings imply Ginkgetin is a potential therapeutic medicine for RCC.
authors.affiliation: Laboratory of kidney Carcinoma, Ningbo Urology and Nephrology Hospital, Urology and Nephrology Institute of Ningbo University, Ningbo 315000, Zhejiang Province, P.R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Laboratory of kidney Carcinoma, Ningbo Urology and Nephrology Hospital, Urology and Nephrology Institute of Ningbo University, Ningbo 315000, Zhejiang Province, P.R. China.
authors.forename: Shuang-Shuang
authors.initials: SS
authors.lastname: Huang
authors.affiliation: Laboratory of kidney Carcinoma, Ningbo Urology and Nephrology Hospital, Urology and Nephrology Institute of Ningbo University, Ningbo 315000, Zhejiang Province, P.R. China.
authors.forename: Xue
authors.initials: X
authors.lastname: Wang
authors.affiliation: Laboratory of kidney Carcinoma, Ningbo Urology and Nephrology Hospital, Urology and Nephrology Institute of Ningbo University, Ningbo 315000, Zhejiang Province, P.R. China.
authors.forename: Zhong-Guan
authors.initials: ZG
authors.lastname: Lou
authors.affiliation: Laboratory of kidney Carcinoma, Ningbo Urology and Nephrology Hospital, Urology and Nephrology Institute of Ningbo University, Ningbo 315000, Zhejiang Province, P.R. China.
authors.forename: Xu-Ping
authors.initials: XP
authors.lastname: Yao
authors.affiliation: Laboratory of kidney Carcinoma, Ningbo Urology and Nephrology Hospital, Urology and Nephrology Institute of Ningbo University, Ningbo 315000, Zhejiang Province, P.R. China.
authors.forename: Guo-Bin
authors.initials: GB
authors.lastname: Weng
keywords: Apoptosis; Caspase assay; Ginkgetin; JAK2/STAT3; Renal cell carcinoma