Phospholipid composition, phosphoinositide metabolism and metastatic capacity in murine melanoma B16 variants at different stages of growth.
Experimental efforts to identify characteristic features of metastatic subpopulations have led to the selection of strains of specialized cells with high and low metastatic potential in the hope that by studying their biochemical and biophysical properties we might start to clarify how tumour cells metastasize. We report data on the phospholipid composition of three variants of murine melanoma B16: F1, with low metastatic potential; F10, highly metastatic when injected i.v.; and BL6, highly metastatic, spontaneous metastases developing from a primary s.c. tumour. Cells were studied at different stages of growth: subconfluent cultures (40-70 x 10(3) cells/cm2) or dense cultures (140-170 x 10(3) cells/cm2). Total phospholipid content decreased as cell density increased in all variants; these changes can probably be related to the reduction in cell volume with increasing cell numbers in the well. As a consequence of this reduction, the amounts of individual phospholipids also decreased in dense cultures. Phosphatidylinositol behaved differently in the highly metastatic variants. In the F1 strain it was three times lower than would be expected from the total phospholipid reduction, while in F10 and BL6 levels increased when cell density increased. Differences in phosphatidylinositol level were also found between variants within each density, suggesting that phosphoinositide synthesis may be related to the metastatic potential of the variants. Incorporation of ([3H] myo)-inositol incorporation into phospholipids over a period of 4 h was greater in F1 cells than in F10 and BL6 at both cell densities.(ABSTRACT TRUNCATED AT 250 WORDS)
Lligona Trulla
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Istituto di Ricerche Farmacologiche Mario Negri, Milano, Italy.
Magistrelli
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A
Salmona
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Tacconi
M T
MT
D000818:Animals; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D008546:Melanoma, Experimental / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D009362:Neoplasm Metastasis; D010716:Phosphatidylinositols / Q000378:metabolism; D010743:Phospholipids / Q000032:analysis / Q000378:metabolism*; D013997:Time Factors
D010716:Phosphatidylinositols; D010743:Phospholipids