Published online Feb 15, 1999. doi: 10.3748/wjg.v5.i1.53
Revised: November 27, 1998
Accepted: December 16, 1998
Published online: February 15, 1999
AIM To detect the congenital expression patterns of mdr-1 gene in commonly encountered malignant tumors in clinic, and the relationship between the expression of mdr-1 gene and the prognostic morphology in esophageal carcinomas.
METHODS A total of 151 resected samples of malignant tumors without preoperative treatment were taken from Anyang City Tumor Hospital. The congenital expression of their mdr-1 gene was detected with reverse transcripti on polymerase chain reaction (RT-PCR) and was compared with each other. The positive incidence of mdr-1 gene in 46 samples of esophageal carcinoma was compared with their differentiated grades, TNM stages and macroscopic types, and the precautions and advantages of RT-PCR were evaluated.
RESULTS All the 151 samples were confirmed to be malignant histopathologically, including cancers of stomach and gastric cardia (n = 51), esophagus (n = 46), colorectum (n = 16), breast (n = 15), thyroid (n = 10), lung (n = 9) and uterine cervix (n = 24). The positive expression rate of their mdr-1 gene was 33.3%, 37%, 31.3%, 13.2%, 40%, 55%, and 0% respectively. All the 46 samples of esophageal carcinoma were pathologically confirmed to be squamous cell carcinoma. The total expression rate of their mdr-1 gene was 37% (17/46), 35% (6/17), 40% (8/20), and 33% (3/9) for differentiation grade I, II and III respectively. The expression rate of TNM classification was 33% (6/18), 40% (5/12) and 37% (6/16) in stage IIa, IIb and III. The expression rate was 33% (3/9) in ulcerous type, 37% (3/8) in constrictive types, 33% (5/15) in fungoid types, and 40% (6/14) in medullary types. No statistically significant difference was found.
CONCLUSION Compared with other methods, RT-PCR is more simple, reliable and accurate in detecting mdr-1 gene expression in tissues of tumor. The overexpression of mdr-1 gene in these neoplasms suggested that cases should be handled differently for chemotherapy with rational use of drugs. Excision is the chief treatment for carcinoma of esophagus. The expression of mdr-1 gene in tissues of esophageal cancer is correlated with the parameters of tumor molecular biology which are independent of histopathological mor phology.