Cellular heterogeneity in human epithelial neoplasms

Production of various marker substances in human ovarian cancer cell lines of epithelial origin

Some characteristics of cell biology and the production of various tumor markers were examined using 8 human ovarian cancer cell lines of epithelial origin. Structural abnormalities of chromosomes 1, 3, and 6 were relatively common karyotypic changes among the cell lines. Cytoplasmic estradiol or progesterone receptor was not detected in any of the cell lines. A significant heterogeneity of the production of various tumor markers (ferritin, tissue peptide antigen, carcinoembryonic antigen, carbohydrate antigens 125, and 19-9) was noted among the cell lines grown in culture medium supplemented with serum. Three of the 8 cell lines were adapted to proliferate in completely synthetic serum-free culture medium. In addition to marker substances described above, small amounts of progesterone or human chorionic gonadotropin were produced in 2 of the 3 cell lines grown in serum-free culture medium. These results indicate that various marker substances including tumor markers are not produced consistently by human ovarian cancer cells of epithelial origin.

Radiosensitivity testing of primary cervical carcinoma: evaluation of intra- and inter-tumour heterogeneity

Biopsies from 89 patients with cervical carcinoma were studied using a clonogenic assay to obtain values for the surviving fraction at 2 Gy (SF2). Heterogeneity in intrinsic radiosensitivity was investigated by independently processing multiple biopsies from 18 tumors. No significant differences between intra-tumour SF2 values were demonstrated (p = 0.30). The results have shown that intra-tumour heterogeneity is not a limitation to radiosensitivity testing using the Courtenay-Mills assay. A wide range of values (0.13-0.97) for SF2 was obtained with a mean value of 0.47 +/- 0.18 (+/- 1 S.D., CV = 38%) for 52 squamous cell carcinomas and 0.59 +/- 0.27 for four adenocarcinomas. There were statistically significant differences between the individual tumours (p less than 0.001). From the analysis-of-variance of all the SF2 results it appears to be the surviving fractions below about 0.40 and those above about 0.7 which show significant differences in radiosensitivity between pairs of tumours (p = 0.05). Also 36% of the values of SF2 show significant differences from the mean SF2 of all tumours. The storage of tumour cell suspensions in liquid nitrogen improved the colony-forming efficiency (CFE) but it did not alter the radiosensitivity.

The growth kinetics of human tumours

Little recent work has been done on the growth kinetics of human tumours although sophisticated radiological techniques are now available. Such sequential radiological studies would provide valuable insights into the natural history of human tumours and their response to treatment.

Expression of membrane receptors and (proto)oncogenes during the ontogenic development and neoplastic transformation of the intestinal mucosa

The functional relationship between membrane receptors involved in signal transduction and (proto) oncogene expression has been explored during the ontogenic development and differentiation of the intestinal mucosa in man and rat. The present review develops detailed picture of the current understanding of some mechanisms underlying growth and function of normal, immortalized and cancerous intestinal epithelial cells.