B7-H1 PD-L1 stem cell

Tumor-mediated bypass of immune checkpoint inhibitor (ICI) therapy with anti-programmed death-1 (PD-1), anti-programmed death-ligand 1 (PD-L1, also called B7-H1 or CD274) or anti-cytotoxic T lymphocyte associated antigen-4 (CTLA-4) is a challenge of current years in the area of cancer immunotherapy. Alternative immune checkpoints (AICs) are molecules beyond the common PD-1, PD-L1 or CTLA-4, and are upregulated in patients who show low/no ICI responses. These are members of B7 family including B7-H2 (ICOS-L), B7-H3 (CD276), B7-H4 (B7x), V-domain immunoglobulin suppressor of T cell activation (VISTA), B7-H6, HHLA2 (B7-H5/B7-H7) and catabolic enzymes like indoleamine 2,3-dioxygenase 1 (IDO1), and others that are also contributed to the regulation of tumor immune microenvironment (TIME)...

Myeloproliferative neoplasms (MPNs) are clonal hematopoietic diseases that belong to the spectrum of myeloid malignancies (MyMs), which also include myelodysplastic syndromes (MDS), acute myeloid leukemia (AML), and chronic myelogenous leukemia (CML). While hematopoietic stem cell transplantation (HSCT) is a potentially curative therapeutic approach to many MyMs, the associated morbidity and mortality have necessitated the development of non-HSCT therapeutics for symptom management and disease course modification...

The incidence of kidney cancer has been increasing globally during the past two decades. Renal cell carcinoma (RCC) is the most aggressive subtype of kidney cancer, which usually deteriorates with epithelial-mesenchymal transition (EMT) that facilitates the migration and invasion of cancer cells. Till now, the underlying mechanism remains unclear. In this study, we demonstrated that programmed death ligand 1 (PD-L1/B7-H1/CD274) could induce EMT and enhance RCC cell cancer stemness through up-regulation of SREBP-1c...

The resurgence of cancer immunotherapy stems from an improved understanding of the tumor microenvironment. The PD-1/PD-L1 axis is of particular interest, in light of promising data demonstrating a restoration of host immunity against tumors, with the prospect of durable remissions. Indeed, remarkable clinical responses have been seen in several different malignancies including, but not limited to, melanoma, lung, kidney, and bladder cancers. Even so, determining which patients derive benefit from PD-1/PD-L1-directed immunotherapy remains an important clinical question, particularly in light of the autoimmune toxicity of these agents...

INTRODUCTION: While current treatment for acute myeloid leukemia is characterized by high response rates, patients' long-term outcome is still disappointing, due to frequent relapse and ineligibility of the often elderly patients for stem cell transplantation approaches. Considerable efforts have, thus, been made to incorporate immunotherapeutic approaches in the acute myeloid leukemia (AML) consolidation, with so far disappointing clinical benefit. The B7 family ligand programmed-death receptor-ligand 1 (PD-L1, B7-H1, CD274) has been recently described (with conflicting results) to be expressed on AML blast cells, and interaction with its receptor on T cells, programmed death receptor-1 (PD-1, CD279), has been shown to suppress T-cell functions and to allow survival of dormant AML cells in animal models...

The lack of understanding of the interplay between hematopoietic stem cells (HSCs) and the immune system has severely hampered the stem cell research and practice of transplantation. Major problems for allogeneic transplantation include low levels of donor engraftment and high risks of graft-versus-host disease (GVHD). Transplantation of purified allogeneic HSCs diminishes the risk of GVHD but results in decreased engraftment. Here we show that ex vivo expanded mouse HSCs efficiently overcame the major histocompatibility complex barrier and repopulated allogeneic-recipient mice...

OBJECTIVE: It is generally assumed that plasma cells from multiple myeloma (MM) patients do not express the stem cell marker CD34. This assumption has led to several clinical trials based on autologous CD34(+) cell transplantation. However, the results of these trials have been disappointing. MATERIALS AND METHODS: We investigated the presence of CD34(+) cell populations in RPMI 8226, KARPAS 417, and U266 MM cell lines in vitro and during their growth as plasmacytoma tumors in nonobese diabetic severe combined immunodeficient mice, and in plasma cells isolated from the bone marrow of 38 MM patients...