Cell culture methods were modified for the NCI-H322 and NCI-H358 cells to obtain a system for kinetic studies of prostanoid synthesis from arachidonic acid free of perturbations in temperature and gas equilibrium.  Unidispersed suspensions of trypsinized cells were attached to Cytodex-1 microcarriers at a ratio of 35-40 cels per microcarrier.  After culturing at 37 degrees in 5% CO2: 95% water-saturated air atmosphere for 2-3 days the microcarriers were almost completely covered.  The microcarrier attached NCI-H322 and NCI-H358 cells were prepared for experimentation via two washes with Hank's balanced salt solution containing Ca++ and Mg++ (HBSS+) followed by suspension in HBSS+ containing glucose (2mg/ml).  Quantitative and qualitative analysis by high resolution capillary gas chromatography negative ion chemical ionization mass spectrometry indicate that these cell lines derived from human bronchioloalveolar carcinomas synthesize PGE2, PGD2 and PGF2alpha in response to stimulation by exogenous arachidonic acid and by the ionophore A23187.  The response of the NCI-H322 and NCI-H358 cells to these stimuli are rapid with prostanoid synthesis being complete within four minutes.  PGE2 is the most abundant arachidonate metabolite synthesized in there two human lung carcinoma cells.  In addition to studies of arachidonate metabolism in the NCI-H322 and NCI-H358 cells, high resolution capillary gas chromatography mass spectrometry has also been employed to assess prostanoid production in human lung carcinoma tissue, renal cell carcinoma tissue, in tumor tissue from nude mice bearing human lung carcinomas and from normal tissues in which the tumors were resident.  Our studies suggest that prostanoid synthesis may be a characteristic unique to a group or subclass of human malignancies and may be relevant diagnostically and in the classification of human tissues.