Ho Chih-Ming, Lee Fa-Kung, Yen Ting-Lin, Huang Shih-Hung, Cheng Wen-Fang
Gynecologic Cancer Center, Department of Obstetrics and Gynecology, Cathay General Hospital Taipei, Taiwan.
School of Medicine, Fu Jen Catholic University Hsinchuang, New Taipei, Taiwan.
Am J Cancer Res. 2022 Apr 15;12(4):1686-1706. eCollection 2022.
Ovarian clear cell cancer stem-like/spheroid cells (OCCCSCs) were associated with recurrence, metastasis, and chemoresistance in ovarian clear cell carcinoma (OCCC). We evaluated the anti-tumor effects of 5-aza-2-deoxycytidine (5-aza-dC) combined with everolimus (RAD001) on human OCCC. We investigated parental OCCCSCs and paclitaxel-resistant cell lines derived from OCCCSCs and . A Western blot analysis showed that the 5-aza-dC and RAD001 combination therapy was associated with the COL6A3-AKT-mTOR pathway. The OCCCSCs expressed high levels of stemness markers: CD117, ALDH1, NANOG, OCT4, and CD133. The 5-aza-dC and RAD001 combination inhibited proliferation and survival with up to 100-fold more potency in OCCCSCs compared to OCCC cells. This combination showed significant anti-tumor activity; it preferentially diminished OCCCSC stemness levels and spheroid numbers . Limiting dilution assays showed that OCCCSCs possessed tumor-initiating capacity. The 5-aza-dC and RAD001 combination significantly enhanced the inhibition of tumor growth compared to the 5-aza-dC or RAD001 alone. OCCCSCs showed higher expression levels of COL6A3, phospho-AKT, phospho-mTOR, and phospho-Rictor compared to OCCCs. Silencing COL6A3 or abolishing the phospho-AKT-mTOR-Rictor pathway with 5-aza-dC and RAD001 treatment further enhanced OCCCSC apoptosis and reduced OCCCSC stemness. In conclusion, 5-aza-dC combined with RAD001 effectively controlled OCCC and OCCCSC growth by inhibiting the COL6A3-AKT-mTOR pathway.
卵巢透明细胞癌干细胞样/球样细胞（OCCCSCs）与卵巢透明细胞癌（OCCC）的复发、转移和化疗耐药相关。我们评估了5-氮杂-2'-脱氧胞苷（5-aza-dC）联合依维莫司（RAD001）对人OCCC的抗肿瘤作用。我们研究了亲本OCCCSCs以及源自OCCCSCs的紫杉醇耐药细胞系。蛋白质免疫印迹分析表明，5-aza-dC与RAD001联合治疗与COL6A3-AKT-mTOR信号通路相关。OCCCSCs表达高水平的干性标志物：CD117、醛脱氢酶1（ALDH1）、NANOG、八聚体结合转录因子4（OCT4）和CD133。与OCCC细胞相比，5-aza-dC与RAD001联合用药在抑制OCCCSCs增殖和存活方面的效力高达100倍。该联合用药显示出显著的抗肿瘤活性；它优先降低OCCCSC的干性水平和球样细胞数量。极限稀释分析表明，OCCCSCs具有肿瘤起始能力。与单独使用5-aza-dC或RAD001相比，5-aza-dC与RAD001联合用药显著增强了对肿瘤生长的抑制作用。与OCCCs相比，OCCCSCs显示出更高水平的COL6A3、磷酸化AKT、磷酸化mTOR和磷酸化rictor表达。用5-aza-dC和RAD001处理沉默COL6A3或阻断磷酸化AKT-mTOR-rictor信号通路，可进一步增强OCCCSC凋亡并降低OCCCSC干性。总之，5-aza-dC联合RAD001通过抑制COL6A3-AKT-mTOR信号通路有效控制OCCC和OCCCSC的生长。
