JAK3 and neoplasm: These treatments caused marked inhibition not only in Cox-2 expression (Fig. 6A, upper panel) but also in PGE2 production by the tumor cells (Fig. 6A, lower panel) and significant protection for the IL2Rγc signaling in CD4+ T cells i.e., up-regulation of γc expression, Jak-3/Stat-5 phosphorylation and increase in Bcl-2 level (Fig. 6B, upper panel), which offered these T cells relive from the apoptotic insult (Fig. 6B, lower panel).