Sensitivity of esophageal squamous cell carcinoma cells to rapamycin can be improved by siRNA-interfered expression of p70S6K.
- Author:
Mingyue LIU
1
;
Zhaoming LU
;
Yan ZHENG
;
Yao CUI
;
Jiazhen WANG
;
Guiqin HOU
2
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Antibiotics, Antineoplastic; pharmacology; Carcinoma, Squamous Cell; drug therapy; metabolism; pathology; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Esophageal Neoplasms; drug therapy; metabolism; pathology; Humans; Mice; Mice, Nude; RNA, Small Interfering; Ribosomal Protein S6 Kinases, 70-kDa; genetics; metabolism; Signal Transduction; Sirolimus; pharmacology; Transfection
- From: Chinese Journal of Oncology 2015;37(12):885-889
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo explore the differences in sensitivity to rapamycin of five esophageal squamous cell carcinoma cell lines with different differentiation and the changes of sensitivity of the cells after siRNA-interfered expression of p70S6K.
METHODSEffects of rapamycin on proliferation of ESCC cell lines with different differentiation, EC9706, TE-1, Eca109, KYSE790 and KYSE450 cells, were investigated using cell counting kit 8 (CCK-8) assay, and according to the above results, the EC9706 cells non-sensitive to rapamycin were chosen to be transfected with p70S6K-siRNA. The changes in sensitivity of cells to rapamycin were measured in vitro and in vivo using CCK-8 kit, flow cytometry and tumor formation in nude mice.
RESULTSCCK-8 results showed that all the five cell line cells were sensitive to low concentration of rapamycin (<100 nmol/L), but TE-1 and EC9706 cells, which were with poor differentiation, showed resistance to high concentration of rapamycin. After EC9706 cells were treated with 50, 100, 200, 500 and 1 000 nmol/L rapamycin and p70S6K-siRNA, the proliferation rates of EC9706 cells were (48.67 ± 1.68)%, (15.45 ± 1.54)%, (14.00 ± 0.91)%, (10.97 ± 0.72)% and (2.70 ± 0.32)%, respectively, and were significantly lower than that of cells treated with 50, 100, 200, 500 and 1 000 nmol/L rapamycin and control siRNA [(74.53 ± 1.71)%, (68.27 ± 1.35)%, (71.74 ± 2.44)%, (76.23 ± 1.02)% and (80.21 ± 2.77)%] (P<0.05 for all). The results of flow cytometry showed that the ratios of cells in G1 phase of the p70S6K-siRNA, rapamycin and p70S6K-siRNA+ rapamycin groups were (53.82 ± 1.78)%, (57.87 ± 4.01)% and (73.73 ± 3.68)%, respectively, significantly higher than that in the control group (46.09 ± 2.31)% (P<0.05 for all). The results of tumor formation test in vivo showed that the inhibitory effect of rapamycin on tumor growth was stronger after the cells were transfected with p70S6K-siRNA, and the inhibition rate was 96.5%.
CONCLUSIONESCC cells with different differentiation have different sensitivity to rapamycin, and p70S6K-siRNA can improve the sensitivity of cells to rapamycin in vitro and in vivo.
