Association of cyclin D1 expression in lung cancer and the smoking habits of patients

This study examined whether or not cyclin D1 expression is associated with the smoking habits of patients with non-small cell lung carcinomas (NSCLC). Immunohistochemistry was used to analyze 181 NSCLC samples for the express ion of cyclin D1. Expression of cyclin D1 protein was found in 130 out of 1 81 cases (72%). A significant relationship between cyclin D1 expression and stage or histological classification was not observed. The carcinomas of s mokers expressed cyclin D1 in 77% of the cases while carcinomas of non-smok ers expressed this protein only 57% of the time (P < 0.01, Fisher's exact t est). The correlation between smoking and cyclin D1 expression was maintain ed when the analysis was limited to squamous cell lung carcinomas. However, no correlation was found between cyclin D1 expression and the smoking habi ts of patients with adenocarcinomas, This can be explained by the fact that the development of adenocarcinomas - in contrast to squamous cell lung car cinomas - is not closely related to tobacco smoke. (C) 1999 Elsevier Scienc e Ireland Ltd. All rights reserved.