SYNTHESIS AND RELEASE OF HUMAN GROWTH HORMONE FROM LUNG CARCINOMA IN CELL CULTURE

Cells obtained from the lung carcinoma Summary of a patient with hypertrophic pulmonary osteoarthropathy were maintained in culture for 4 months. Synthesis of human growth hormone (H.G.H.) in vitro was demonstrated by the incorporation of label from ¹⁴C-leucine into material with the characteristics of H.G.H. on gel filtration and paper chromatography. Release of immunoreactive human growth hormone (I.R.H.G.H.) from the cultured cells was stimulated by theophylline and dibutyryl cyclic-3',5'-adenosine monophosphate. The patient was found to have a diabetic glucose-tolerance test and abnormally high plasma concentrations of I.R.H.G.H. which returned to normal after resection. The tumour contained a higher concentration of I.R.H.G.H. than the adjacent lung. These findings are consistent with synthesis and release of H.G.H. by the carcinoma in vivo.