Gong Jianhua, He Li, Ma Jingping, Zhang Jiahong, Wang Lixin, Wang Jipeng
Department of Respiratory Medicine, Jingzhou Central Hospital, Jingzhou Hubei, 434020, PR China.
J BUON. 2017 Mar-Apr;22(2):454-461.
To investigate the relationship between microRNA (miR)-17-5p, miR-92a, and let-7b expression and resistance to the non-small cell lung cancer (NSCLC) targeted drug Gefitinib.
The human NSCLC cell line A549 and its drug resistant strain A549/GR (Gefitinib Resistant) was used in this study. The expression of miR-17-5p, miR-92a, and let-7b in different NSCLC cell lines was detected before and after transfection using real-time fluorescent PCR. Cell viability was detected using the CCK8 method. Cell cloning was performed to examine cell proliferation; cell apoptosis before and after transfection was evaluated using flow cytometry.
miR-17-5p and miR-92a expression in A549/ GR cells was 3.23 ± 0.92 and 9.29 ± 3.13 fold higher than in A549 cells respectively (p<0.05). In addition, let-7b expression in A549/GR cells was 29.37 ± 9.32% fold higher than in A549 cells (p<0.05). A549 cell sensitivity to Gefitinib was significantly decreased after transfection with the miR-17-5p mimic, miR-92a mimic, or the let-7b inhibitor (p<0.05), whereas the sensitivity of A549/GR cells to Gefitinib was significantly increased after transfection with miR-17-5p inhibitor, miR-92a inhibitor, or the let-7b mimic (p<0.05). A549 transfected with miR-17-5p mimic, miR- 92a mimic, and/or let-7b inhibitor formed more colonies than non-transfected controls (p<0.05); A549/GR transfected with miR-17-5p inhibitor, miR-92a inhibitor and let-7b mimic formed fewer colonies than the control group (p<0.05). The apoptosis rate of A549 cells transfected with miR-17-5p mimic, miR-92a mimic, or let-7b inhibitor was significantly lower than that of the control group (p<0.05); the apoptosis rate of A549/GR cells transfected with miR- 17-5p inhibitor, miR-92a inhibitor, or let-7b mimic was significantly higher than that of the control group (p<0.05).
Increased miR-17-5p and miR-92a expression and decreased let-7b expression can significantly induce proliferation and inhibit apoptosis of lung cancer cells, while reducing lung cancer cell sensitivity to Gefitinib.
探讨微小RNA（miR）-17-5p、miR-92a和let-7b表达与非小细胞肺癌（NSCLC）靶向药物吉非替尼耐药性之间的关系。
本研究采用人NSCLC细胞系A549及其耐药株A549/GR（吉非替尼耐药）。使用实时荧光定量PCR检测转染前后不同NSCLC细胞系中miR-17-5p、miR-92a和let-7b的表达。采用CCK8法检测细胞活力。进行细胞克隆以检测细胞增殖；使用流式细胞术评估转染前后的细胞凋亡。
A549/GR细胞中miR-17-5p和miR-92a的表达分别比A549细胞高3.23±0.92倍和9.29±3.13倍（p<0.05）。此外，A549/GR细胞中let-7b的表达比A549细胞高29.37±9.32%（p<0.05）。用miR-17-5p模拟物、miR-92a模拟物或let-7b抑制剂转染后，A549细胞对吉非替尼的敏感性显著降低（p<0.05），而用miR-17-5p抑制剂、miR-92a抑制剂或let-7b模拟物转染后，A549/GR细胞对吉非替尼的敏感性显著增加（p<0.05）。用miR-17-5p模拟物、miR-92a模拟物和/或let-7b抑制剂转染的A549比未转染的对照组形成更多的集落（p<0.05）；用miR-17-5p抑制剂、miR-92a抑制剂和let-7b模拟物转染的A549/GR比对照组形成的集落更少（p<0.05）。用miR-17-5p模拟物、miR-92a模拟物或let-7b抑制剂转染的A549细胞的凋亡率显著低于对照组（p<0.05）；用miR-17-5p抑制剂、miR-92a抑制剂或let-7b模拟物转染的A549/GR细胞的凋亡率显著高于对照组（p<0.05）。
miR-17-5p和miR-92a表达增加以及let-7b表达降低可显著诱导肺癌细胞增殖并抑制其凋亡，同时降低肺癌细胞对吉非替尼的敏感性。
