目的 研究醉茄素A通過Janus激酶（JAK）/信號轉導與轉錄激活子（STAT）通路對人肝癌耐藥細胞HepG2/阿霉素（ADM）凋亡的影響，并探討JAK/STAT通路在其中可能的作用機制。方法 體外培養(yǎng)HepG2/ADM細胞，分為對照組、醉茄素A 2.5、5.0、10.0 μmol/L組。CCK-8法檢測細胞增殖情況；Hoechst33342染色法觀察細胞形態(tài)學變化；Annexin V-FITC/PI雙染色法檢測細胞凋亡情況；Western blotting法檢測凋亡相關蛋白B淋巴細胞瘤-2（Bcl-2）、cleaved caspase-3以及JAK/STAT通路中磷酸化JAK2（p-JAK2）、STAT3（p-STAT3）蛋白表達情況。結果 醉茄素A 2.5、5.0、10.0 μmol/L組HepG2/ADM細胞增殖受到明顯抑制，并呈時間和劑量相關性（P<0.05）。與對照組相比，醉茄素A 2.5、5.0、10.0 μmol/L組HepG2/ADM細胞部分細胞核發(fā)生碎片化、固縮，熒光強度增大，細胞凋亡指數(shù)及凋亡率顯著升高（P<0.05），cleaved caspase-3蛋白表達水平顯著升高（P<0.05），Bcl-2、p-JAK2、p-STAT3蛋白表達水平顯著降低（P<0.05）。結論 醉茄素A可促進人肝癌耐藥細胞HepG2/ADM凋亡，其機制可能與抑制JAK/STAT通路活化，下調抑凋亡蛋白表達及上調促凋亡蛋白表達有關。

Objective To study the effect of withaferin A on apoptosis of HepG2/ADM cells through Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway, and to explore the possible mechanism of JAK/STAT pathway. Methods HepG2/ADM cells were cultured in vitro and divided into control group, withaferin A 2.5, 5.0, and 10.0 μmol/L groups. CCK-8 method was used to detect cell proliferation; Hoechst33342 staining was used to observe the morphological changes; Annexin V-FITC/PI double staining was used to detect apoptosis; and Western blotting was used to detect the expressions of apoptosis related protein b-lymphoma-2 (Bcl-2), cleared caspase-3, and phosphorylated JAK2, STAT3 in JAK/STAT pathway. Results The proliferation of HepG2/ADM cells in the withaferin A 2.5, 5.0, and 10.0 μmol/L groups was significantly inhibited in a time and dose-dependent manner (P<0.05). Compared with the control group, some nucleus of HepG2/ADM cells in the withaferin A 2.5, 5.0, and 10.0 μmol/L groups had fragmentation and pyknosis, and the fluorescence intensity increased. Compared with the control group, apoptosis index and apoptosis rate in the withaferin A 2.5, 5.0, and 10.0 μmol/L groups increased significantly (P<0.05), and the expression level of cleaved caspase-3 was significantly increased (P<0.05), but the expressions of Bcl-2, p-JAK2, and p-STAT3 proteins decreased significantly (P<0.05). Conclusions Withaferin A can promote the apoptosis of drug-resistant human hepatoma cells HepG2/ADM cells, and its mechanism may be related to the inhibition of JAK/STAT pathway activation, down-regulation of apoptotic protein expression and up-regulation of apoptotic protein expression.

R966

河南省自然科學基金科技攻關項目（172102310011）