Therapeutic antibodies blocking programmed death-1 and its ligand (PD-1/PD-L1) induce durable responses in a substantial fraction of melanoma patients.
Using RNAi methodology, we attenuated PD-L1 in the murine ovarian cell line ID8agg and the melanoma cell line B16 (termed PD-L1<sup>lo</sup> cells), which express basal PD-L1.
The patient did not receive programmed death ligand 1 inhibitor therapy and improved rapidly following complete excision of her melanoma, with clobetasol, doxycycline, and niacinamide.
Programmed death-ligand 1 (PD-L1) has emerged as a potential target for therapeutics in a number of malignant tumors, including melanoma, lung, and colorectal cancer.
To explore this, we retrospectively assessed 114 patients from 4 centers with advanced, BRAF-mutant melanoma who received anti-programmed cell death-1 (PD-1)/PD-L1 antibodies.
The aims of this study were to determine the clinical and histological characteristics of melanoma in transplant recipients, the mutation profile (BRAF, NRAS and c-KIT genes), and the immune tolerance of the tumour microenvironment by immunohistochemical study of the expression of indoleamine 2,3-dioxygenase (IDO), PD1, PD-L1, CD8 and FoxP3.
There is compelling evidence that oncogenic BRAF, in addition to driving melanoma proliferation, differentiation and survival, induces T-cell suppression directly through the secretion of inhibitory cytokines or through membrane expression of co-inhibitory molecules such as the PD-1 ligands PD-L1 or PD-L2.
Subcutaneous immunization with shR-SOCS1-transduced viable tumor cells rendered protection against melanoma in a syngeneic model, with decreased expression of PD-L1 and of matrix metallo-proteinases (MMPs) and CD-10 in those cells.
Therapeutic successes with PD-1/PD-L1 antibodies in melanoma and lung cancer have been followed by approvals in bladder, renal, and head and neck cancers and Hodgkin lymphoma, with others undoubtedly to come.
In the current review, we will briefly summarize the scientific background data supporting the development of PD-1/PD-L1 blockade, and then describe the track record of these antibodies in multiple different histologies ranging from melanoma and lung cancer to less common tumor types as well as discuss biomarkers that may assist in patient selection.
Further studies are warranted to validate the predictive role of inflammatory cell PD-L1 expression in melanoma and determine its biological significance.<i></i>.
A decrease in TNF-α, IL-4, IL-5, IL-6, and IL-10 serum levels was observed in the GK-1/anti-PD-L1 combination group that may explain the beneficial effects of the combination treatment in prolonging the life of mice bearing melanoma.
Many new treatment options in the last years, in particular targeted therapies (i.e. inhibitors of c-KIT, NRAS/MEK or BRAF) and immunotherapies (anti CTLA-4 and anti PD-1/PD-L1 antibodies), have changed the history of cutaneous melanoma.
Our recent report shows that tumor cell-intrinsic CD274 promotes MTORC1 signaling in mouse melanoma and mouse and human ovarian cancer, inhibits autophagy and sensitizes some tumors to clinically available pharmacological autophagy inhibitors and confers resistance to MTOR inhibitors.
Indeed, antibodies binding to CTLA-4, PD-1, or PD-L1 have shown remarkable efficacy, especially in combination therapies, for a number of cancers and have been licensed for the treatment of melanoma, nonsmall cell lung cancer, and renal and bladder cancers.
The beneficial antitumoral activity of programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) has been thoroughly demonstrated in certain metastatic malignancies (e.g. melanoma, non-small cell lung cancer, renal cell carcinoma); however, the therapeutic role in lymphoid cancers is complex.
When present, discordant results were attributable to geographic heterogeneity of the melanoma tissue section rather than differences in PD-L1 antibody staining characteristics.
The current melanoma case is representative of a patient who responded to nivolumab therapy, and showed typical immunological markers for responders such as high PD-L1 expression and high SNV.
Furthermore, PD-L1 overexpresion was significantly associated with poor DFS/PFS in patients with hepatocellular carcinoma (HCC) (HR = 1.72, 95% CI = 1.21-2.46, P = .003), melanoma (HR = 3.39, 95% CI = 2.02-5.69, P <.000), and renal carcinoma, (HR = 5.04, 95% CI = 2.87-8.86, P <.000).
Monoclonal antibodies that block the interaction between PD-1 and PD-L1, by binding to either the ligand or receptor, have shown notable clinical efficacy in patients with a variety of cancers, including melanoma, colorectal cancer, non-small-cell lung cancer and Hodgkin's lymphoma.