DIFFERENTIAL REDUCTION IN THE EXPRESSION OF KERATIN POLYPEPTIDES IN HUMAN GASTRIC CARCINOMAS

Phenotypic expression of keratin polypeptides is known to be dependent on various factors, one of which is malignant transformation. In this study, we compared the pattern of expression of keratin polypeptides between control and malignant gastric tissues by employing different m orphological and biochemical techniques. The results indicated prefere ntial decrease of acidic keratin polypeptides in malignant gastric tis sues. The nonmalignant gastric tissues expressed four keratin polypept ides-two acidic and two basic-whereas in the gastric adenocarcinomas e xpression of only two basic polypeptides was observed. Marked variatio n of keratin expression between the control and malignant gastric tiss ues not only highlights its clinical value as a support to diagnosis b ut also elucidates the underlying changes due to malignant transformat ion.