Spontaneous Peripheral T-cell Responses toward the Tumor-Associated Antigen Cyclin D1 in Patients with Clear Cell Renal Cell Carcinoma

Analyzing samples from patients with primary clear cell renal cell carcinoma (ccRCC), Dannenmann and colleagues identified naturally occurring, polyfunctional Cyclin D1-specific CD8+ T cells from patients with Cyclin-D1+ tumors, and they propose to develop Cyclin D1 as a target for immunotherapy in patients with ccRCC. Renal cell carcinoma (RCC) is a heterogeneous group of kidney cancers with clear cell RCC (ccRCC) as the major subgroup. To expand the number of clinically relevant tumor-associated antigens (TAA) that can be targeted by immunotherapy, we analyzed samples from 23 patients with primary ccRCC for the expression and immunogenicity of various TAAs. We found high-frequency expression of MAGE-A9 and NY-ESO-1 in 36% and 55% of samples, respectively, and overexpression of PRAME, RAGE-1, CA-IX, Cyclin D1, ADFP, C-MET, and RGS-5 in many of the tumor samples. We analyzed the blood of patients with HLA-A2+ ccRCC for the presence of CD8+ T cells specific for TAA-derived HLA-A2–restricted peptides and found spontaneous responses to cyclin D1 in 5 of 6 patients with Cyclin D1–positive tumors. Cyclin D1–specific CD8+ T cells secreted TNF-α, IFN-γ, and interleukin-2 (IL-2), and degranulated, indicating the presence of polyfunctional tumor-specific CD8+ T cells in the blood of these patients with ccRCC. The high frequency (43%) of Cyclin D1 overexpression and the presence of functional cyclin D1–specific T cells in 83% of these patients with ccRCC suggest that cyclin D1 may be a target for immunotherapeutic strategies. Cancer Immunol Res; 1(5); 288–95. ©2013 AACR.