Checkpoint therapy with PD-(L)1 and CTLA4-directed monoclonal antibodies has shown to be extremely effective for many patients with a variety of tumors. PD-1 testing, alone, however, are lacking in selecting patients for therapy – up to 17% of patients who do not meet criteria for PD-1 positivity respond to treatment, and many patients with PD-1 tumors do not respond well to checkpoint therapy. Continue reading
Tag Archives: biomarker
TIGIT, a CTLA4-esque Immune Checkpoint for Cancer
Immune checkpoint-directed therapy is producing unprecedented clinical results in many patients. So much so, that the FDA recently reversed its longstanding policy or approving cancer drugs based on site of origin, to the presence of a biomarker (microsatellite instability (MSI-H) or mismatch-deficient repair (dMDR) as the indication for therapy with pembrolizumab (Ketruda), and PD-1 blocker. Cancers expressing MSI-H or dMDR mutate at a rapid rate, presenting novel epitopes to the immune system, which is readily mobilized against them so that tumor infiltrating T-cells are reliably present. Blocking the PD-1/PD-L1 pathway in this context allows for prolongation of the immune response and better clinical results. Continue reading
Osteopontin – a prognostic marker for cancer progression
Osteopontin (OPN) is a matrix protein that is expressed by osteoclasts, osteoblasts, dendritic cells, fibroblasts, hepatocytes, smooth and skeletal muscle cells, endothelial cells, and kidney cells. It interacts with many cell surface receptors including integrins and CD44. One of the major physiologic functions of OPN is the control of bone mineralization – by binding to specific apatitie crystal faces, it inhibits mineralization. But, OPN is also a pro-inflammatory cytokine that acts in many tissues to recruit monocytes and macrophages and induce cytokine secretion from leukocytes. As such, it has a critical role in tissue remodeling, inflammation, and tumorigenesis. Continue reading