Fatty acid pattern of the different phosphoinositide fractions in human meningiomas

Previous studies showed no differences in the phospholipid content of human meningiomas compared to normal leptomeninges, but only a higher unsaturation degree in the individual phospholipid fractions of tumors. Inasmuch as phosphoinositides play a role in the membrane responsiveness to numerous effectors, we studied the fatty acid pattern of the different phosphoinositide fractions of 14 human meningiomas of different histological origin. The fatty acid analysis revealed remarkable differences among the histological types, and, above all, among the different phosphoinositide fractions of a single tumor class. The phosphoinositides derived from transitional meningiomas appeared to be the most saturated ones, because of their low arachidonic acid content. Furthermore, in all the meningiomas, long chain polyunsaturated fatty acids were present only in the phosphatidylinositol fractions and the polyphosphorylated compounds appeared to be significantly different from the corresponding monophosphorylated ones. The possible significance of the different fatty acid distribution in the three phosphoinositide classes is discussed.