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-2^b x H-2(k)) mouse, grows locally (L-T10) and generates spontaneous lung metastases (M-T10), L-T10 cells were found to express the H-2^b haplotype, whereas M-T10 expressed both the H-2^b and H-2(k) haplotypes. Most L-T10 cloned cells expressed the H-2^b haplotype and were not metastatic. The minority expressed both H-2(k) and H-2^b and were metastatic. Serial transplantations of H-2(k)-negative clones always ended in spontaneous expression of the H-2(k)-haplotype concomitantly with the acquisition of metastatic potency. The expressed H-2(k) seemed to be associated with the metastatic properties inasmuch as an H-2^b-positive-H-2(k)-negative clone, which had lost the expressed H-2^b and was temporarily H-2 negative, remained nonmetastatic until reexpression of the two haplotypes occurred. Serial transfers of H-2(k)-positive clones resulted in the maintenance of the expressed H-2(k) haplotype and the retention of metastatic capacity. A shift toward increased metastatic capacity correlated with H-2(k) 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.