DIVERGENT EFFECTS OF HYPEROSMOLALITY ON STRESS-RESPONSE (HEAT-SHOCK) PROTEIN EXPRESSION IN CULTURED HUMAN TUMOR-CELLS - AN IMMUNOCYTOCHEMICAL STUDY

Exposing cells to adverse conditions usually elicits expression of str ess-response (heat shock) proteins (srp). Here we show that hyperosmol ar growth conditions do not uniformly affect srp expression in MCF-7 a nd HeLa S3 cells, derived from carcinoma of the breast and cervix, res pectively. Thus, whereas srp 27 expression was increased in MCF-7, but not in HeLa S3, the opposite was the case with srp 72. On the other h and, hyperosmolality did not induce alpha B-crystallin or ubiquitin in either cell line. These findings show that srp expression by the huma n tumor cells studied is non-coordinate, suggesting that each srp is i ndependently modulated.