Effect of Yin Yang protein 1 transcriptionally regulating acetyl-CoA carboxylase 1 on the cell migration and lipogenesis in ovarian cancer / 肿瘤研究与临床

ABSTRACT

Objective:To investigate the expression of acetyl-CoA carboxylase 1 (ACC1) in ovarian cancer tissues and cells, and the related mechanisms of the effect of ACC1 on cell migration and lipogenesis in ovarian cancer.Methods:Samples including 1 case of normal ovarian tissue, 1 case of ovarian cancer primary lesion tissue and 1 case of ovarian cancer omentum metastatic tissue diagnosed by pathology examination of patients undergoing surgery resection who admitted to Linyi Cancer Hospital between January 2019 and December 2021 were collected. Immunohistochemistry was used to detect the protein levels of ACC1 and Yin Yang protein 1 (YY1) of all tissues. The PROMO database was used to predict the possible binding sites of YY1 and ACC1 promoter region. Through the assembled viral vector, the HEY cells of human ovarian cancer with ACC1 or YY1 expression [the untreated cells were treated as the negative control (NC)], or knocked down ACC1 or YY1 (the interference sequence sh1, sh2, sh3 was transferred to the target gene, and the negative control sequence shNC was transferred to the interference sequence). Double luciferase reporter gene assay was used to verify the binding sites of YY1 and ACC1 promoter and the activity of transcriptional regulation. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) and Western blot were used to detect the mRNA and protein expression levels of ACC1 and YY1 in the treated HEY cells, respectively. Transwell assay was used to detect the migration ability of HEY cells. Oil red O staining and Nile red staining were used to detect the lipid droplets in HEY cells.Results:The immunohistochemical scores of ACC1 and YY1 were 0, 2, 8 scores and 0, 4, 6 scores, respectively in normal ovarian tissue, primary lesion of ovarian cancer, and omentum metastatic tissue. Transwell assay showed that the number of invasive HEY cells in ACC1 overexpression group was more than that in NC group [(87.7±7.4) vs. (52.2±4.2), t = 5.19, P = 0.003]. The number of invasive HEY cells in ACC1-sh1 group, and ACC1-sh2 group with the knockdown of ACC1 was less than that in shNC group [(21.2±1.5), (29.7±2.3) vs. (56.2±5.3); t value was 6.41, 3.77; P < 0.001, P < 0.005]. The number of lipid droplets in HEY cells in the ACC1 overexpression group was more than that in the control NC group [Oil red O staining: (301±25) vs. (215±21); Nile red staining: (287±15) vs. (207±10); all P < 0.05]; the number of lipid droplets in HEY cells in ACC1-sh1 and ACC1-sh2 group with the knockdown of ACC1 was less than that in ACC1-shNC group [Oil red O staining: (113±8), (119±12) vs. (195±18); Nile red staining: (82±8), (117±11) vs. (165±17); all P < 0.05]. The result of dual luciferase reporter assay showed that overexpression of YY1 promoted the luciferase activity of the wild type ACC1 promoter region report gene ( P = 0.003), while the luciferase activity of the report gene was inhibited compared with the wild type after the mutation of binding sites of YY1 in ACCI promoter region ( P = 0.008). Western blot results showed that the expression levels of YY1 and ACC1 protein in HEY cells with YY1 overexpression group were higher than those in NC group, which indicated a synergistic increasing trend of both YY1 and ACC1; the expression levels of YY1 and ACC1 protein in YY1-sh1 group, YY1-sh2 group and YY1-sh3 group with the knockdown of YY1 were lower than those in the control YY1-shNC group, which indicated a synergistic decreasing trend of both YY1 and ACC1. Conclusions:ACC1 and YY1 are highly expressed in ovarian cancer metastatic tissues and both show a positive correlation trend. The expression level of ACC1 in vitro has an impact on cell migration and lipogenesis in ovarian cancer via YY1 transcriptionally regulating ACC1.