Search results
Results from the WOW.Com Content Network
In cancer, loss of feedback restriction between transcription factors can lead to increased local PD-L1 expression, which could limit the effectiveness of systemic treatment with agents targeting PD-L1. [28] CAR-T [29] and NK cells [30] targeting PD-L1 are being evaluated for treating cancer. pSTAT-1 and PDL-1 expressions also strongly ...
In the cancer disease state, the interaction of PD-L1 on the tumor cells with PD-1 on a T-cell reduces T-cell function signals to prevent the immune system from attacking the tumor cells. [9] Use of an inhibitor that blocks the interaction of PD-L1 with the PD-1 receptor can prevent the cancer from evading the immune system in this way. [9]
Programmed cell death protein 1 (PD-1), (CD279 cluster of differentiation 279). PD-1 is a protein encoded in humans by the PDCD1 gene. [5] [6] PD-1 is a cell surface receptor on T cells and B cells that has a role in regulating the immune system's response to the cells of the human body by down-regulating the immune system and promoting self-tolerance by suppressing T cell inflammatory activity.
Among PD-L1 functions is a key regulatory role on T cell activities. It appears that (cancer-mediated) upregulation of PD-L1 on the cell surface may inhibit T cells that might otherwise attack. PD-L1 on cancer cells also inhibits FAS- and interferon-dependent apoptosis, protecting cells from cytotoxic molecules produced by T cells.
Tumor cells express PD-L1 in high amounts which prevents T cells from attacking them. Another mechanism that cancer cells use is the downregulation of MHC I. Major histocompatibility complex class I (MHC I) molecules are expressed on cell surfaces with the role of alerting the immune system to the presence of infected cells.
The expression of PD-L1 (programmed death-ligand 1; one of the immune checkpoints) has been demonstrated to be a good biomarker of PD-L1 blockade therapy in some cancers. [10] However, there is a need for better biomarkers as there are some predictive errors with PD-L1 expression. [10]
In lung cancer, Trodelvy continues to be evaluated in combination with pembro in first-line PD-L1 high metastatic nonsmall cell lung cancer in the phase 3 EVOKE-03 study.
PD-L1 protein on the surface of normal cells binds to PD-1 receptors on a type of cytotoxic T cells (i.e. CD8+ T cells [11]) and thereby blocks these T-cells from organizing an immune response that would kill them. This PD-L1/CD8+ T cell circuit is one of several immune checkpoint mechanisms for maintaining self-tolerance, i.e. for preventing ...