Vaults are 13 megadalton ribonucleoprotein particles composed largely of the major vault protein (MVP) and two high molecular weight proteins, p240 and p193, and a small vault RNA (vRNA). Increased levels of MVP expression, vault-associated vRNA, and vaults have been linked directly to multidrug resistance (MDR). To further define the putative role of vaults in MDR, we produced monoclonal antibodies against the Mr 193,000 vault protein and studied its expression levels in various multidrug-resistant cell lines. We find that, like MVP, p193 mRNA and protein levels are increased in various multidrug-resistant cell lines. Subcellular fractionation of vault particles revealed that vault-associated p193 levels are increased in multidrug-resistant cells as compared with the parental, drug-sensitive cells. Furthermore, protein analysis of postnuclear supernatants and co-immunoprecipitation studies show that drug-sensitive MVP-transfected tumor cells lack this up-regulation in vault-associated p193. Our observations indicate that vault formation is limited not only by the expression of the MVP but also by the expression or assembly of at least one of the other vault proteins.

Download full-text PDF

Source

Publication Analysis

Top Keywords

vault protein
12
cell lines
12
193000 vault
8
mvp expression
8
multidrug-resistant cell
8
levels increased
8
increased multidrug-resistant
8
vault-associated p193
8
vault
6
protein
5

Similar Publications

Adoptive cell therapy with tumor-infiltrating lymphocytes (TIL) can mediate tumor regression, including complete and durable responses, in a range of solid cancers, most notably in melanoma. However, its wider application and efficacy has been restricted by the limited accessibility, proliferative capacity and effector function of tumor-specific TIL. Here, we develop a platform for the efficient identification of tumor-specific TCR genes from diagnostic tumor biopsies, including core-needle biopsies frozen in a non-viable format, to enable engineered T cell therapy.

View Article and Find Full Text PDF

Endothelial IGFBP6 suppresses vascular inflammation and atherosclerosis.

Nat Cardiovasc Res

January 2025

Department of Endocrinology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.

Beyond dyslipidemia, inflammation contributes to the development of atherosclerosis. However, intrinsic factors that counteract vascular inflammation and atherosclerosis remain scarce. Here we identify insulin-like growth factor binding protein 6 (IGFBP6) as a homeostasis-associated molecule that restrains endothelial inflammation and atherosclerosis.

View Article and Find Full Text PDF

Multi-Omics Study Reveals Nc886/vtRNA2-1 as a Positive Regulator of Prostate Cancer Cell Immunity.

J Proteome Res

December 2024

Facultad de Ciencias, Universidad de la República, Sección Genómica Funcional, Montevideo 11400, Uruguay.

Noncoding RNA 886 has emerged as a pivotal regulatory RNA with distinct functions across tissues, acting as a regulator of protein activity by directly binding to protein partners. While it is well recognized as a tumor suppressor in prostate cancer, the underlying molecular mechanisms remain elusive. To discover the principal pathways regulated by nc886 in prostate cancer, we used a transcriptomic and proteomic approach analyzing malignant DU145, LNCaP, PC3, and benign RWPE-1 prostate cell line models transiently transfected with in vitro transcribed nc886 or antisense oligonucleotides.

View Article and Find Full Text PDF
Article Synopsis
  • Immunotherapy has enhanced survival rates for patients with advanced clear cell renal cell carcinoma (ccRCC), but many patients still develop resistance to treatment.
  • A study examined tumor samples from patients with both treatment-naïve and treatment-exposed ccRCC, revealing that tumors exposed to immunotherapy contained more immune cells (like CD8+ T cells and neutrophils) and showed significant changes in cellular markers.
  • Key findings included increased expression of COL4A1 and ITGAV in the stroma of treated tumors, suggesting a need for further investigation into how these changes impact the tumor immune environment and potential new therapies.
View Article and Find Full Text PDF

Exploring the role of vault complex in the nervous system: a literature review.

Rev Neurosci

November 2024

Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, 1416634793, Iran.

Vault RNAs (vtRNAs) are a novel group of non-coding RNAs that are involved in various signaling mechanisms. vtRNAs are joined by three proteins major vault protein (MVP), vault poly (ADP-ribose) polymerase (VPARP), and telomerase-associated protein 1 (TEP1) to form the vault complex. In humans, only four vtRNA including vtRNA 1-1, vtRNA 1-2, vtRNA 1-3, vtRNA 2-1) have been discovered.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!