RNPC1 induces sensitivity of HER-2-positive breast cancer BT474 cells to trastuzumab through ;upregulation of HER2
10.3760/cma.j.issn.0253-3766.2016.03.003
- VernacularTitle:RNA 结合蛋白38通过增加人表皮生长因子受体2的表达诱导乳腺癌BT474细胞对曲妥珠单抗的敏感性
- Author:
Chunlian LI
1
;
Xujie ZHOU
;
Peipei LOU
;
Tiansong XIA
;
Liang SHI
;
Ying WANG
;
Qiang DING
Author Information
1. 210029南京医科大学第一附属医院乳腺外科
- Keywords:
Subject words] Breast neoplasms;
RNA binding protein 38;
Human epidermal growth factor receptor-2;
Proliferation;
Apoptosis
- From:
Chinese Journal of Oncology
2016;38(3):172-178
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the sensitivity of HER-2-positive BT474 breast cancer cells to trastuzumab after knockdown or overexpression of RNA binding protein 38 ( RNPC1 ) .Methods The expressions of RNPC1 and HER-2 mRNA were detected by qRT-PCR, and the expressions of RNPC1, HER-2 and PI3K/AKT proteins were detected by Western blot after transfected with RNPC1 lentiviral vector, respectively.The experimental groups were treated with different concentration of trastuzumab, and cell apoptosis rate was analyzed by 7-AAD/APC double staining flow cytometry, and cell growth inhibition rate was tested by cell counting kit 8 ( CCK-8) .The expression of apoptosis-related proteins was detected by Western blot assay.Results The results of qRT-PCR showed that overexpression of RNPC1 increased the expressions of RNPC1 and HER-2 mRNA, and the expressions of RNPC1 and HER-2 were decreased after RNPC1 knockdown.The knockdown of RNPC1 decreased the expressions of RNPC1 and HER-2.Moreover, overexpression of RNPC1 decreased and knockdown of RNPC1 increased the levels of p-PI3K and p-AKT while the total protein expressions of both were marginally changed.The results of analysis using a cell counting CCK-8 kit showed that the RNPC1 overexpressed group had a higher growth inhibition rate [(20.33± 1.25)%,(35.38±2.05)%,(50.43±2.12)%,(65 .35±2.08)%and(76.00±2.16)%, respectively] than that of the control group [(13.67±1.24)%,(27.86±2.05)%,( 39.72±1.69)%,(53.33±1.70)%and(62.68± 2.07)%] when treated with different concentrations of trastuzumab (5, 10, 15, 20 and 25 μg/ml).The cell apoptosis rates in the RNPC1-overexpressed group [ ( 19.46 ±1.06 )%, ( 30.87 ±0.98 )%, ( 50.45 ± 1.1)3%, respectively] were also increased compared with that in the control group [(14.38±0 .64)%,(21.65± 1.24)%,(38.03±0.85)%] when treated with different concentrations of trastuzumab (0, 10, 20 and 30μg/ml) ( P<0.05 for all).Reverse results were observed in the RNPC1 knockdown experiments [ experimental groups:(9.67±1.18)%, ( 21.67 ±1.23)%, ( 30.33 ±1.25)%, ( 40.33 ±1.69)%, and ( 53.00 ± 1.63)%] compared with those of control groups:[(14.00±0.82)%, (27.67±1.25)%, (39.67±1.79)%, (53.67±1.50)%, and (63.33±1.52)%];and experimental groups:[(11.64±0.68)%, (16.60±1.01)%, and (25.14±3.12)%] compared with those of the control groups: [(14.71±0.61)%, (22.65±0.96)%, and (39.03±0.85)%].The overexpression of RNPC1 increased the expression levels of Bim and Bad and decreased the level of Bcl-xl, and reverse result was observed after knockdown of RNPC1.Conclusion RNPC1 may promote the sensitivity of breast cancer cells to trastuzumab through the increased expression of HER-2 in the BT474 breast cancer cells.
