Expression of major histocompatibility class I and class II antigens and intercellular adhesion molecule-1 on...

Major histocompatibility complex (MHC) antigens and adhesion molecules, such as the intercellular adhesion molecule-1 (ICAM-1), appear to play an important role in the immunological recognition and destruction of tumour cells. We, therefore, examined the expression patterns of these proteins on primary tumours of 91 patients with operable non-small cell lung cancer (NSCLC). Applying immunohistochemistry with monoclonal antibody (MAb) W6/32 against a common framework determinant of HLA class I antigens revealed a deficient expression in 33.0% of the cases analysed, while neo-expression of either HLA class II antigens (MAb TAL.1B5) or ICAM-1 (MAb PA3.58-14) was observed in 26.4 or 29.7% of tumours, respectively. Analysis of consecutive tumour specimens indicated that HLA antigens and ICAM-1 were frequently coexpressed. With regard to clinicopathological risk factors, we could demonstrate a preferential expression of those markers in patients with locally restricted and well-differentiated tumours or no lymph node metastases, which was more pronounced in adenocarcinomas than in squamous cell carcinomas. In contrast, the presence versus the absence of HLA antigens and ICAM-1 was not correlated with the rate of tumour recurrence or overall survival in patients with NSCLC. In conclusion, the co-ordinated expression of immunologically relevant cell surface molecules on primary NSCLC is a frequent event that correlates with distinct parameters of favourable prognosis. However, we have no evidence that the immune response facilitated by these molecules can effectively influence the clinical course of the disease.