AIM:To further understand the molecular basis for gastriccardia carcinogenesis and to provide etiological clues.METHODS:Endoscopic mucosa biopsy and histopathologicalexaminations were made on 37 subjects from a high incidencearea for both esophageal and gastric cardia carcinomas innorthem Chins.All the biopsy samples were fixed in 850 ml.~(-1)Lalcohol and embedded in paraffin.Each block contained onepiece of tissue and was serially section at 5μm.Immunohistochemistry(ABC)was carried out on these gastriccardia samples to determine the alterations of p16 and Rb.RESULTS:Based on the histopathlogical examination therewere 11 cases of chronic superficial gastritis,12 cases ofchronic atrophic gastritis and 14 cases of dysplasia.Theimmunostaining demonstrated different levels of unclearimmunostaining of p16 and Rb in normal gastric cardiatissue and the tissues with different severity of lesions.Withthe lesions progressing,the positive immunostaining ratesfor p16 protein had a decreasing tendency.In contrast,thepositive immunostaining rate for Rb protein had anincreasing tendency.There was a significant negativerelationship batween the two parameters.Changes of p16was CSG 11(100%),CAG 7(58%),DYS 4(29%)andchanges of Rb was CSG 2(18%),CAG 8(67%)and DYS 12(86%).(P<0.05).CONCLUSION:The alterations of p16 and Rb protein may playa role in the early stages of gastric cardia carcinogenesis. AIM:To further understand the molecular basis for gastriccardia carcinogenesis and to provide etiological clues.METHODS:Endoscopic mucosa biopsy and histopathologicalexaminations were made on 37 subjects from a high incidencearea for both esophageal and gastric cardia carcinomas innorthem Chins.All the biopsy samples were fixed in 850 ml.~-1Lalcohol and embedded in paraffin.Each block contained onepiece of tissue and was serially section at 5μm.Immunohistochemistry(ABC)was carried out on these gastriccardia samples to determine the alterations of p16 and Rb.RESULTS:Based On the histopathlogical examination therewere 11 cases of chronic superficial gastritis,12 cases ofchronic atrophic gastritis and 14 cases of dysplasia.The immunostaining demonstrated different levels of unclearimmunostaining of p16 and Rb in normal gastric cardiatissue and the tissues with different severity of lesions.With the lesions progressing, The positive immunostaining ratesfor p16 protein had a decreasing tend ency.In contrast,the positive immunostaining rate for Rb protein had anincreasing tendency.There was a significant negativerelationship batween the two parameters.Changes of p16was CSG 11(100%),CAG 7(58%),DYS 4(29%)andchanges of Rb was CSG 2 (18%), CAG 8 (67%) and DYS 12 (86%). (P<0.05). CONCLUSION: The alterations of p16 and Rb protein may playa role in the early stages of gastric cardia carcinogenesis.