The expression of c-myc in the tissues of human laryngeal squamous cell carcinoma and the effect of siRNA-mediated inhibition of c-myc on proliferation in laryngeal carcinoma Hep-2 cells.
- Author:
Jianzhong SANG
1
;
Li LIU
;
Fang TIAN
;
Hongjun JIN
;
Linlin YUAN
;
Weihua LOU
Author Information
1. Department of Otorhinolaryngology Head and Neck Surgery, the First Affiliated Hospital, Zhengzhou University, Zhengzhou, 450052, China.
- Publication Type:Journal Article
- MeSH:
Adult;
Aged;
Apoptosis;
Carcinoma, Squamous Cell;
metabolism;
pathology;
Cell Line, Tumor;
Cell Proliferation;
Female;
Humans;
Laryngeal Neoplasms;
metabolism;
pathology;
Male;
Middle Aged;
Proto-Oncogene Proteins c-myc;
genetics;
metabolism;
RNA Interference;
RNA, Messenger;
genetics;
RNA, Small Interfering;
genetics
- From:
Journal of Clinical Otorhinolaryngology Head and Neck Surgery
2011;25(15):695-700
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To detect the expression of c-myc in the tissue of laryngeal squamous cell carcinoma. RNA interference(RNAi) was employed to inhibit the expression of c-myc in Hep-2 cells and to evaluate the effects of c-myc as a target for gene therapy in laryngeal carcinoma.
METHOD:Immunohistochemistry was used to determine the protein levels of c-myc and Rb in 80 cases of laryngeal squamous cell carcinoma and 30 cases of polyp of vocal cord. Hep-2 cells were transfected with c-myc siRNA, c-myc protein and mRNA levels were detected using Western Blotting and RT-PCR. Cell viability was detected by MTT after the Hep-2 cells were transfected with c-myc siRNA for different times or transfected with different concentrations c-myc siRNA. The sensitivity of Hep-2 cells to 5-Fu transfected with or without c-myc siRNA was evaluated also by MTT. Hep-2 cells were transfected with c-myc siRNA in combination with 5-Fu for 48 h and then analyzed cell apoptosis by flow cytometry.
RESULT:Immunohistochemical analysis showed that c-myc was highly expressed in the tissues of laryngeal squamous cell carcinoma while the expression of Rb was lower. The protein and mRNA levels of c-myc decreased after transfected with c-myc siRNA. The results of MTT showed that the c-myc siRNA inhibited Hep-2 cells growth in a concentration-dependent manner. When transfected with c-myc siRNA(50 nmol/L), the cells were inhibited in a time-dependent manner. Compared with the untransfected cells, the viability of transfected Hep-2 cells was significantly suppressed at the same concentration of 5-Fu (P < 0.05). C-myc siRNA combination with 5-Fu could obviously increase cell apoptosis, even in the low concentration of 5-Fu (P < 0.05).
CONCLUSION:The protein level of C-myc has highly expressed in tumor tissues. C-myc siRNA can effectively inhibit the expression of c-myc and has anti-proliferation effects, increasing the sensitivity of Hep-2 cells to 5-Fu. Therefore,c-myc might be a good target for cancer treatment.
