The VEGFR tyrosine kinase inhibitors (TKIs) pazopanib and sunitinib are FDA-approved first-line treatment options for advanced RCC; however, other treatment options in this setting are available, including the recently approved combination of nivolumab (anti-PD-1) and ipilimumab (anti-cytotoxic T-lymphocyte-associated protein-4 [CTLA-4]) for patients with intermediate or poor risk.
ICIs target Cytotoxic T Lymphocytes Antigen 4 (CTLA-4), programmed death 1 (PD-1), or its ligand (PD-L1), showing promising therapeutic efficacy in RCC.
The introduction of the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1) immune checkpoint inhibitors and their subsequent listing on the Pharmaceutical Benefits Scheme for use in metastatic melanomas, renal cell carcinomas and non-small-cell lung cancers has resulted in routine use of these agents in oncology practices, including in regional areas.
In addition, the combination of antibodies to CTLA-4 (ipilimumab) and to PD-1 (nivolumab) has been found to confer a survival benefit in patients with melanoma or renal cell carcinoma.
In recent years, antibody-based immunotherapies targeting immune checkpoint receptors PD-1 and CTLA-4 have demonstrated clinical efficacy in metastatic RCC (mRCC) patients, leading to FDA approval of the combination of nivolumab and ipilimumab in treatment-naïve patients with intermediate- or poor-risk disease in April 2018.
Checkpoint inhibitors, such as cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) and programmed cell death-1 (PD-1) monoclonal antibodies have changed profoundly the treatment of melanoma, renal cell carcinoma, non-small cell lung cancer, Hodgkin lymphoma, and bladder cancer.
Antibodies targeting two negative immune checkpoint pathways, namely cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), and programmed cell death-ligand 1 (PD-L1), have been approved first for patients with melanoma, squamous non-small cell lung cancer (NSCLC), and renal cell carcinoma.
Immune-checkpoint inhibitors (ICPIs), including antibodies against cytotoxic T-lymphocyte associated antigen 4 and programmed cell death protein 1, have been shown to induce durable complete responses in a proportion of patients in the first-line and refractory setting in advanced melanoma and renal cell carcinoma.
Monoclonal antibodies targeting the regulatory immune "checkpoint" receptors CTLA-4, PD-1, and PD-L1 are now standard therapy for diverse malignancies including melanoma, lung cancer, and renal cell carcinoma.
The advent of checkpoint inhibitors has revolutionized systemic therapy for many malignancies, including renal cell carcinoma (RCC) where multiple PD-1, PD-L1, and CTLA-4 inhibitors have demonstrated responses and improved survival for patients in clinical trials.
In wild-type BALB/c mice, inoculation of syngeneic epithelial cells continuously secreting the CTLA-4-ErbB2 fusion vaccine in the vicinity of subcutaneously growing ErbB2-expressing renal cell carcinomas resulted in the rejection of established tumors, accompanied by the induction of ErbB2-specific antibodies and cytotoxic T cells.
Therefore, our data suggest the CTLA-4 gene may be a candidate as a renal adenocarcinoma susceptibility gene, but does not play an important role in colon cancer.