Cell lines established from small cell lung cancer (SCLC), a neuroendocrine tumor, have low or absent expression of class I major histocompatibility complex antigens. To determine whether this phenomenon occurs also in vivo, 244 routine paraffin-embedded tumors including 32 SCLC and 79 non-SCLC (NSCLC) lung cancers were studied for expression of β2-microglobulin (β2m) by an avidin-biotin coupled immunoperoxidase technique. The majority of SCLC tumors lacked β2m expression, while some had weak, focal expression. In contrast, most NSCLC expressed β2m, often strongly. The difference between SCLC and NSCLC was highly significant statistically, suggesting that β2m can be used as a clinical immunodiagnostic marker for distinguishing NSCLC from SCLC. In addition, certain other neuroendocrine tumors (neuroblastoma, bronchial and midgut carcinoid tumors) lacked β2m expression, whereas some (pheochromocytoma, medullary thyroid carcinoma, and peripheral neuroectodermal tumors) usually stained positively. Such non-neuroendocrine tumors as colon, breast, and prostate carcinomas showed moderate to high expression of β2m. Selective absence of β2m expression by certain neuroendocrine tumors appears to be a phenomenon of biological and diagnostic importance.
|Original language||English (US)|
|Number of pages||8|
|State||Published - Jan 1 1986|
ASJC Scopus subject areas
- Pathology and Forensic Medicine
- Molecular Biology
- Cell Biology