Alterations in major histocompatibility complex phenotypes of mouse cloned T10 sarcoma cells: association with shifts from nonmetastatic to metastatic cells.

The T10 sarcoma, induced in a (C57BL/6J X C3HeB/-FeJ)F1 (H-2b X H-2k) mouse, grows locally (L-T10) and generates spontaneous lung metastases (M-T10). L-T10 cells were found to express the H-2b haplotype, whereas M-T10 expressed both the H-2b and H-2k haplotypes. Most L-T10 cloned cells expressed the H-2b haplotype and were not metastatic. The minority expressed both H-2k and H-2b and were metastatic. Serial transplantations of H-2k-negative clones always ended in spontaneous expression of the H-2k haplotype concomitantly with the acquisition of metastatic potency. The expressed H-2k seemed to be associated with the metastatic properties inasmuch as an H-2b-positive--H-2k-negative clone, which had lost the expressed H-2b and was temporarily H-2 negative, remained nonmetastatic until reexpression of the two haplotypes occurred. Serial transfers of H-2k-positive clones resulted in the maintenance of the expressed H-2k haplotype and the retention of metastatic capacity. A shift toward increased metastatic capacity correlated with H-2k expression occurred during serial transfers of every clone tested. Expression of major histocompatibility complex components, rather than their loss, may potentiate the metastatic capacity of tumor cells.