Department of Gynaecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan City, China.
Cancer Biother Radiopharm. 2021 Mar;36(2):202-210. doi: 10.1089/cbr.2019.3363. Epub 2020 Nov 6.
Long noncoding RNA (lncRNA)-PRLB (progression-associated lncRNA in breast cancer) has been identified to enhance the drug resistance of breast cancer cells. In this study, the authors explored PRLB effect in the paclitaxel (Tax) resistance of ovarian cancer cells and revealed the role of RSF1 (remodeling and spacing factor 1)/nuclear factor kappaB (NF-κB) signaling in this process. Tax resistance was established in CAOV3 and SKOV3 cell lines. The expressions of PRLB in Tax resistant tissues and cells of ovarian cancer were detected using the real time polymerase chain reaction assay. MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide] and flow cytometry were used to detect cell survival and apoptosis. The RNA-binding protein immunoprecipitation (RIP) assay and/or the luciferase gene reporter assay were used to assess the cross talk among miR-150-5p and PRLB/RSF1. PRLB expression was obviously enhanced in the Tax resistant ovarian cancer tissues and cells. Depletion of PRLB induced a significant decrease in the IC50 value of the CAOV3/Tax and SKOV3/Tax cells and increased cell apoptosis, as well as increased miR-150-5p expression through a direct binding. In addition, miR-150-5p upregulation decreased the luciferase activity of PRLB and RSF1, whereas this effect was abolished when the putative binding sites were mutated. And overexpression of RSF1 significantly rescued the effect of PRLB downregulation-caused decrease in the IC50 value and the increase in cell apoptosis and the decreased expressions of RSF1 and p-p65. This study reveals that knockdown of PRLB improves the sensitivity of ovarian cancer cells to Tax, at least in part, through inhibiting the activation of RSF1/NF-κB signaling through targeting miR-150-5p.
长链非编码 RNA（lncRNA）-PRLB（乳腺癌进展相关 lncRNA）已被确定可增强乳腺癌细胞的耐药性。在这项研究中，作者探讨了 PRLB 在卵巢癌细胞紫杉醇（Tax）耐药中的作用，并揭示了 RSF1（重塑和间隔因子 1）/核因子 kappaB（NF-κB）信号在该过程中的作用。 在 CAOV3 和 SKOV3 细胞系中建立了 Tax 耐药。采用实时聚合酶链反应检测 Tax 耐药组织和卵巢癌细胞中 PRLB 的表达。采用 MTT [3-（4,5-二甲基-2-噻唑基）-2,5-二苯基-2-H-四唑溴盐]和流式细胞术检测细胞存活和凋亡。采用 RNA 结合蛋白免疫沉淀（RIP）测定法和/或荧光素酶基因报告基因测定法评估 miR-150-5p 与 PRLB/RSF1 之间的串扰。 在 Tax 耐药的卵巢癌组织和细胞中，PRLB 的表达明显增强。PRLB 耗竭导致 CAOV3/Tax 和 SKOV3/Tax 细胞的 IC50 值显著降低，细胞凋亡增加，并且通过直接结合增加 miR-150-5p 的表达。此外，miR-150-5p 的上调降低了 PRLB 和 RSF1 的荧光素酶活性，而当假定的结合位点发生突变时，该作用被消除。RSF1 的过表达可显著挽救 PRLB 下调引起的 IC50 值降低、细胞凋亡增加以及 RSF1 和 p-p65 表达降低的作用。 本研究揭示，通过靶向 miR-150-5p 抑制 RSF1/NF-κB 信号的激活，敲低 PRLB 可至少部分提高卵巢癌细胞对 Tax 的敏感性。
