摘要
AIM:To investigate the change in expression of p53 ,Bcl-2 ,and Bax genes in human colon cancer cells transplanted into nude mice after hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy and thermochemoradiotherapy. METHODS:Human colon cancer cell line (HT29) was transplanted into the hind limbs of nude mice. Under laboratory simulated conditions of hyperthermia (43℃,60 min),the actual radiation doses and doses of mitomycin C (MMC) were calculated in reference to the clinical radiotherapy for human rectal cancer and chemotherapy prescription for colon cancer. The mice were divided into 6 groups according to the treatment approaches:hyperthermia,chemotherapy,radiotherapy,thermochemotherapy,thermoradiotherapy,and thermochemoradiotherapy. The mice were sacrificed at different time points and the tumor tissue was taken for further procedures. The morphologic changes in membrane,cytoplasm and nuclei of tumor cells of p53,Bcl-2,and Bax after treatment,were observed by immunohistochemistry staining. RESULTS:All of the six treatment modalities down-regulated the expression of p53,Bcl-2 and up-regulated the expression of Bax at different levels. The combined therapy of hyperthermia,with chemotherapy,and/or irradiation showed a greater effect on down-regulating the expression of p53 (0.208 ± 0.009 vs 0.155 ± 0.0115,P < 0.01) and Bcl-2 (0.086 ± 0.010 vs 0.026 ± 0.0170,P < 0.01) and up-regulating Bax expression (0.091 ± 0.0013 vs 0.207 ± 0.027,P < 0.01) compared with any single therapy.CONCLUSION:Hyperthermia enhances the effect of radio-and chemotherapy on tumors by changing the expression of apoptosis genes,such as p53,Bcl-2 and Bax.
AIM: To investigate the change in expression of p53, Bcl-2, and Bax genes in human colon cancer cells transplanted into nude mice after hyperthermia, chemotherapy, radiotherapy, thermochemotherapy, thermoradiotherapy and thermochemoradiotherapy. METHODS: Human colon cancer cell line (HT29) was transplanted into the hind limbs of nude mice. Under laboratory simulated conditions of hyperthermia (43℃, 60 min), the actual radiation doses and doses of mitomycin C (MMC) were calculated in reference to the clinical radiotherapy for human rectal cancer and chemotherapy prescription for colon cancer. The mice were divided into 6 groups according to the treatment approaches: hyperthermia, chemotherapy, radiotherapy, thermochemotherapy, thermoradiotherapy, and thermochemoradiotherapy. The mice were sacrificed at different time points and the tumor tissue was taken for further procedures. The morphologic changes in membrane, cytoplasm and nuclei of tumor cells of p53, Bcl-2, and Bax after treatment, were observed by immunohistochemistry staining. RESULTS: All of the six treatment modalities downregulated the expression of p53, Bcl-2 and up-regulated the expression of Bax at different levels. The combined therapy of hyperthermia, with chemotherapy, and/or irradiation showed a greater effect on down-regulating the expression ofp53 (0.208 ± 0.009 vs 0.155 ± 0.0115, P 〈 0.01) and Bcl-2 (0.086 ± 0.010 vs 0.026 ± 0.0170, P 〈 0.01) and up-regulating Bax expression (0.091 ± 0.0013 vs 0.207 ±0.027, P 〈 0.01) compared with any single therapy.CONCLUSION: Hyperthermia enhances the effect of radio- and chemotherapy on tumors by changing the expression of apoptosis genes, such as p53, Bcl-2 and Bax.
基金
Supported by the Clinical Research Foundation of Tianjin Medical University, No. 2002KY18
关键词
过高热
细胞凋亡
裸体老鼠
细胞线
化学疗法
Hyperthermia
Apoptosis
p53
Bcl-2
Bax
Nude mice
Colon cancer
Cell line