Altered phosphatidylcholine (PC) metabolism in epithelial ovarian cancer (EOC) could provide cholinebased imaging approaches as powerful tools to improve diagnosis and identify new therapeutic targets. The increase in the major choline-containing metabolite phosphocholine (PCho) in EOC compared with normal and nontumoral immortalized counterparts (EONT) may derive from (a) enhanced choline transport and choline kinase (ChoK)-mediated phosphorylation, (b) increased PC-specific phospholipase C (PC-plc) activity, and (c) increased intracellular choline production by PC deacylation plus glycerophosphocholine-phosphodiesterase (GPC-pd) or by phospholipase D (pld)-mediated PC catabolism followed by choline phosphorylation. Biochemical, protein, and mRNA expression analyses showed that the most relevant changes in EOC cells were (a) 12-fold to 25-fold ChoK activation, consistent with higher protein content and increased ChoKα (but not ChoKβ) mRNA expression levels; and (b) 5-fold to 17-fold PC-plc activation, consistent with higher, previously reported, protein expression. PC-plc inhibition by tricyclodecan-9-yl-potassium xanthate (D609) in OVCAR3 and SKOV3 cancer cells induced a 30% to 40% reduction of PCho content and blocked cell proliferation. More limited and variable sources of PCho could derive, in some EOC cells, from 2-fold to 4-fold activation of pld or GPC-pd. Phospholipase A 2 activity and isoform expression levels were lower or unchanged in EOC compared with EONT cells. Increased ChoKα mRNA, as well as ChoK and PC-plc protein expression, were also detected in surgical specimens isolated from patients with EOC. Overall, we showed that the elevated PCho pool detected in EOC cells primarily resulted from upregulation/activation of ChoK and PC-plc involved in PC byosinthesis and degradation, respectively. Cancer Res; 70(5); 2126-35. ©2010 AACR.

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Abstract. In this report we show that Drosophila melanogaster muscles contain the standard form of the thick filament protein paramyosin, as well as a novel paramyosin isoform, which we call miniparamyosin . We have isolated Drosophila paramyosin using previously established methods. This protein is =105 kD and cross-reacts with polyclonal antibodies made against Caenorhabditis elegans or Heliocopris dilloni paramyosin. The Heliocopris antibody also cross-reacts with a

Morphologic and metabolic studies have been carried out on Friend leukemia cell (FLC) tumors (grown in DBA/2 mice) or fibrosarcomas (grown in C3H/HeN or C3H/HeJ mice) shortly after peritumoral injection of recombinant mouse tumor necrosis factor (TNF) alpha. Marked vascular congestion and focal extravasation of erythrocytes were observed as soon as 1 hr after injection of either FLC tumors or fibrosarcomas with TNF. Focal areas of disaggregation of tumor cells were observed 1 hr after injection of TNF. Intraluminal thrombi (composed of degranulated platelets and fibrin) were detected 3 and 6 hr after TNF treatment, and were associated with areas of depletion of endothelial cell cytoplasm. To correlate these morphologic changes in the tumor with alterations in tumor metabolism, NMR spectroscopy and biochemical studies were undertaken on freshly dissected FLC tumors and fibrosarcomas shortly after injection of TNF. The earliest metabolic alterations observed after 1 hr in TNF-treated FLC tumors of fibrosarcomas were: (i) increase in the average intratumoral pH; (ii) decrease in the levels of ATP. These phenomena were not associated with a reduced glycolytic capacity of TNF-treated tumors as, at these early times after injection, the levels of lactic acid were virtually the same for TNF-treated or control treated tumors. Alterations in the levels of some products of phospholipid degradation (GroPCho, GroPEtn, GroP and Cho) also occurred in these tumors as early as 3 hr after TNF treatment. These metabolic changes were not observed in ascitic FLC tumors after TNF treatment. We suggest that TNF induces alterations in tumor blood vessels which subsequently lead to changes in tumor metabolism and tumor degeneration.

Peri-tumoral injection of recombinant human interleukin-1 beta in mice transplanted s.c. with Friend erythroleukemia cells (FLC) resulted in marked inhibition of tumor growth and increased survival. However, in vitro treatment of FLC (745 or 3Cl-8) with IL-1 beta barely inhibited cell multiplication. IL-1 beta, injected into established solid tumors, induced marked morphologic changes. Vascular congestion and focal extravasation of erythrocytes were observed as early as 6 hr after injection with IL-1 beta of FLC and L1210 tumors and HeJ16 fibrosarcomas. Focal areas of disaggregation of tumor cells and tumor necrosis were observed 6 and 24 hr after IL-1 injection. These morphologic changes were similar to those observed in FLC tumors or HeJ16 fibrosarcomas treated with TNF-alpha or beta. These cytokines determined morphological changes in tumor blood vessels of FLC tumors within 1 hr of injection. Freshly dissected FLC tumors and their tissue extracts were studied by Nuclear Magnetic Resonance (NMR) spectroscopy, shortly after peri-tumoral injection of IL-1 beta or TNF-beta. After 6 hr, both cytokines induced a 3-fold reduction in the levels of two catabolites, glycerophosphorylcholine and glycerophosphorylethanolamine, an accumulation of sn-glycerol 3-phosphate and a more than 10-fold increase in the choline/phosphorylcholine ratio. These results are similar to those reported for TNF-alpha, and can be interpreted on the basis of an activation of glycerophosphorylcholine phosphodiesterase (EC 3.1.4.2) and partial inhibition of choline kinase (EC 2.7.1.32). IL-1 beta and TNF-beta (like TNF-alpha) also induced alkaline shifts (0.10-0.25 units) in the average intratumoral pH value. We suggest that alterations of tumor blood vessels may be the primary events in solid tumors treated with IL-1 beta or TNF. Such alterations lead to early changes in tumor metabolism and subsequent tumor cell degeneration.