Distinction of two different classes of small-cell lung cancer cell lines by enzymatically inactive neuron-specific enolase

Abstract

Summary Neuron specific enolase (NSE) is widely used as a neuro-endoctrine marker. However the presence of NSE in many non-neuroendocrine tissues has raised questions on the specificity of NSE. We have investigated NSE immunoreactivity (NSA-ag), y-enolase activity and total enolase activity in small cell lung cancer (SCLC) (Bepler et al., 1987;Carney et al., 1985;Gazdar et al., 1985;Bepler et al., 1989a;Broers et al., 1985;Moody et al., 1985;Broers et al., 1988 NSE is widely used as a neuroendocrine marker. NSEimmuno reactivity is not only seen in neurons, but also in neuroendocrine cells present in endocrine glands and in the diffuse neuroendocrine systems of the lung, intestine, thymus and skin. NSE has been demonstrated in tumours, thought to arise from the neuroendocrine cell system, such as SCLC, neuroblastoma, carcinoid, pancreatic islet cell tumours and medullary thyroid carcinoma (Schmechel et al., 1978;Tapia et al., 1981;Wick et al., 1983). NSE is also present in erythrocytes, lymphocytes and platelets (Marangos et al., 1980b;Hullin et al., 1980) and in malignant lymphomas, testicular cancer, hypernephroma and non-small cell lung cancer (Takashi et al., 1989;Ariyoshi et al., 1983;Kuzmits et al., 1987;Pinto et al., 1989;Oka et al., 1989;Niehans et al. 1988). Such observations question the correlation between NSE and the neuroendocrine cell system (Schmechel, 1985 SCLC-cell linesThe SCLC-cell lines were generously provided by the