UNASSIGNED: 2535 Background: A decrease in the T cell receptor    chain expression has been described in @entity281 . The association with response to treatment and the mechanisms leading to this diminished expression are unclear. In vitro models suggest that arginase production may decrease CD3   expression. METHODS: We examined the expression of CD3   chain and arginase activity in preRx samples of peripheral blood mononuclear cells from pts with mRCC receiving @entity1199 Rx on a CWG Phase III trial,    chain expression was studied by florescence intensity (MFI) and serum arginase activity by conversion of @entity369 to @entity7222 . Results were compared to blood obtained from 33 healthy normal volunteers (NV). RESULTS: Of 106 with a pre-Rx blood samples 18 pts responded (7 CR, 11 PR). MFI for CD3    was 21.39 +/- 8.15 for the pts vs 35.43 +/- 12.24 for the NV. Mean arginase was 128.55 for pts vs 32.63 for NV. Serum arginase levels and CD3    chain expression were inversely related (r= -0.31, p<0.01 ). Low and extremely low    expression was defined as 1 or 2 SD below the mean of the NV's. Median survival was 26, 19 and 14mos and @entity5 response was 19% (8/42), 18% 10/56 and 0% (0/8) for pts with normal, low and extremely low    expression. Arginase was 128.55 for pts vs 32.63 for NV. No correlation of survival or response with arginase expression was observed. . Data on other immune abnormalities including @entity5750 +, @entity404 / @entity2902 reg T cells, @entity2952 and @entity7803 , and inducible cytokines are still being analyzed. CONCLUSIONS: These data suggest that mRCC is associated with decrement in    chain and increased arginase expression. Decreased    chain is associated with poor response and survival outcome Given the absence of response in pts with low    chain in these data, its role as a potential selection factor should be further investigated. The role of arginase in the loss of CD3   and in response to immunotherapy requires further study No significant financial relationships to disclose.

Role of CD3   expression and arginase activity in predicting response and survival in metastatic renal cell carcinoma (mRCC) patients receiving XXXX .

@entity404 :: ('920', 'Gene') :: ['CD4'] @entity5750 :: ('929', 'Gene') :: ['CD14'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor'] @entity7222 :: ('CHEBI:18257', 'Chemical') :: ['ornithine'] @entity2952 :: ('3932', 'Gene') :: ['LCK'] @entity281 :: ('MESH:D007239', 'Disease') :: ['malignancy and chronic infections'] @entity7803 :: ('3718', 'Gene') :: ['Jak-3'] @entity2902 :: ('3559', 'Gene') :: ['CD25'] @entity1199 :: ('3558', 'Gene') :: ['IL-2'] @entity369 :: ('CHEBI:29016', 'Chemical') :: ['arginine']
@entity1199 :: (3558,Gene) :: ['IL-2']
