Autoimmune antibodies correlate with immune checkpoint therapy-induced toxicities.

Immune checkpoint (IC) therapy provides substantial benefits to cancer patients but can also cause distinctive toxicities termed immune-related adverse events (irAEs). Biomarkers to predict toxicities will be necessary to improve management of patients receiving IC therapy. We relied on serological analysis of recombinant cDNA expression libraries to evaluate plasma samples from patients treated with IC therapy and identified autoantibodies, both in pretreatment and on-treatment samples prior to the development of irAEs, which correlate with the development of immune-related hypophysitis (anti-GNAL and anti-ITM2B autoantibodies) and pneumonitis (anti-CD74 autoantibody).

Clonal expansion of CD8 T cells in the systemic circulation precedes development of ipilimumab-induced toxicities.

Immune checkpoint therapies, such as ipilimumab, induce dramatic antitumor responses in a subset of patients with advanced malignancies, but they may also induce inflammatory responses and toxicities termed immune-related adverse events (irAEs). These irAEs are often low grade and manageable, but severe irAEs may lead to prolonged hospitalizations or fatalities. Early intervention is necessary to minimize morbidities that occur with severe irAEs.

Caveolin-1-LRP6 signaling module stimulates aerobic glycolysis in prostate cancer.

Caveolin 1 (Cav-1) is a plasma membrane-associated protein with the capacity to modulate signaling activities in a context-dependent fashion. Interactions between Cav-1 and low-density lipoprotein receptor-related protein 6 (LRP6) were reported to be important for the regulation of Wnt-β-catenin (β-cat) signaling. Cav-1 also interacts with insulin and IGF-I receptors (IGF-IR/IR) and can stimulate IR kinase activities.

Serum caveolin-1, a biomarker of drug response and therapeutic target in prostate cancer models.

We investigated the effect of dasatinib and sunitinib on tyrosine kinase (TK) signaling, caveolin-1 (Cav-1) expression and secretion and proliferation of PC-3 and DU145 prostate cancer cells in vitro and in vivo. Treatment of both cell lines with either dasatinib or sunitinib reduced phosphorylation of PDGFR, VEGFR2, Akt, FAK, Src (dasatinib only) and Cav-1, and reduced cellular and secreted levels of Cav-1. Both agents dose-dependently inhibited proliferation of these cells.

Anti-caveolin-1 antibodies as anti-prostate cancer therapeutics.

Caveolae are critical cell surface structures important in coordinated cell signaling and endocytosis. One of the major proteins of caveolae is caveolin 1 (Cav-1). Cellular levels of Cav-1 are associated with cancer progression.

Association of caveolin-1 and -2 genetic variants and post-treatment serum caveolin-1 with prostate cancer risk and outcomes.

Background: Caveolin-1 (cav-1) is overexpressed by metastatic prostate cancer (PC) cells. Pre-operative serum cav-1 levels have been shown to be a prognostic marker for PC recurrence. This study evaluated the relationship between post-treatment serum cav-1 levels and single nucleotide polymorphisms (SNPs) in the cav-1 and -2 genes with risk of PC, aggressive PC, PC recurrence or death.

Caveolin-1 regulates VEGF-stimulated angiogenic activities in prostate cancer and endothelial cells.

Caveolin-1 (cav-1) is a multifunctional protein and major component of caveolae membranes serving important functions related to signal transduction, endocytosis, transcytosis, and molecular transport. We previously showed that cav-1 is overexpressed and secreted by metastatic prostate cancer cells. We now report that cav-1 gene transduction (Adcav-1) or recombinant cav-1 (rcav-1) protein treatment of cav-1-negative prostate cancer cell line LP-LNCaP or cav-1(-/-) endothelial cells potentiated VEGF-stimulated angiogenic signaling.

Functional analysis of secreted caveolin-1 in mouse models of prostate cancer progression.

Previously, we reported that caveolin-1 (cav-1) is overexpressed in metastatic prostate cancer and that virulent prostate cancer cells secrete biologically active cav-1. We also showed that cav-1 expression leads to prosurvival activities through maintenance of activated Akt and that cav-1 is taken up by other cav-1-negative tumor cells and/or endothelial cells, leading to stimulation of angiogenic activities through PI-3-K-Akt-eNOS signaling. To analyze the functional consequences of cav-1 overexpression on the development and progression of prostate cancer in vivo, we generated PBcav-1 transgenic mice.

Tumor cell-secreted caveolin-1 has proangiogenic activities in prostate cancer.

Caveolin, a major structural component of specialized plasma membrane invaginations (caveolae) that participate in diverse cellular activities, has been implicated in the pathogenesis of several human diseases, including cancer. We showed in earlier studies that caveolin-1 (cav-1) is consistently and strongly overexpressed in metastatic prostate cancer and is secreted in a biologically active form by virulent prostate cancer cells. Using both in vitro and in vivo model systems, we now present evidence supporting a proangiogenic role for cav-1 in prostate cancer development and progression.

Preoperative serum caveolin-1 as a prognostic marker for recurrence in a radical prostatectomy cohort.

Purpose: Up-regulation of caveolin-1 (cav-1) is associated with virulent prostate cancer, and serum cav-1 levels are elevated in prostate cancer patients but not in benign prostatic hyperplasia. In this study, we evaluated the potential of high preoperative serum cav-1 levels to predict biochemical progression of prostate cancer. The value of the combined preoperative markers, prostate-specific antigen (PSA), biopsy Gleason score, and serum cav-1 for predicting biochemical recurrence was also investigated.

Stromal antiapoptotic paracrine loop in perineural invasion of prostatic carcinoma.

Caveolin-1 (cav-1) is a major scaffolding component of cell membrane invaginations (caveolae). It is involved in sequestering numerous effectors and signaling molecules and has antiapototic activities in prostate cancer. Perineural invasion (PNI) is associated with decreased apoptosis of cancer cells both in human tissues and the in vitro PNI model.

Caveolin-1 maintains activated Akt in prostate cancer cells through scaffolding domain binding site interactions with and inhibition of serine/threonine protein phosphatases PP1 and PP2A.

Previously it has been reported that caveolin-1 (cav-1) has antiapoptotic activities in prostate cancer cells and functions downstream of androgenic stimulation. In this study, we demonstrate that cav-1 overexpression significantly reduced thapsigargin (Tg)-stimulated apoptosis. Examination of the phosphatidylinositol 3-kinase (PI3-K)/Akt signaling cascade revealed higher activities of PDK1 and Akt but not PI3-K in cav-1-stimulated cells compared to control cells.

Development of an immunoassay for serum caveolin-1: a novel biomarker for prostate cancer.

Purpose: Caveolin-1 (cav-1), the major protein component of caveolae, plays an important role in multiple signaling pathways, molecular transport, and cellular proliferation and differentiation. The specific functions of cav-1/caveolae are highly cell and context dependent. We have previously shown that cav-1 expression is increased in metastatic human prostate cancer and that cav-1 cellular protein expression is predictive of recurrence of the disease after radical prostatectomy.

Therapeutic targets for metastatic prostate cancer.

Prostate cancer is the most commonly diagnosed non-cutaneous cancer in adult males. Although prostate cancer that is confined to the gland can be cured in many patients using surgery or radiation, these treatments are only effective for localized tumors and the long-term failure rates for these treatments suggests that prostate cancer can metastasize relatively early in the course of the disease. Once prostate cancer has metastasized there are no curative therapies.

The role of caveolin-1 in androgen insensitive prostate cancer.

Purpose: We summarize the literature regarding androgen insensitive prostate cancer and caveolin-1. Caveolin-1 is a major structural component of caveolae, membrane micro-domains known to have important roles in signal transduction and lipid transport.

Materials And Methods: A review of the literature relevant to androgen insensitive caveolin-1 and prostate cancer included the first published report in 1998 through those published in March 2002.

mRTVP-1, a novel p53 target gene with proapoptotic activities.

We identified a novel mouse gene, mRTVP-1, as a p53 target gene using differential display PCR and extensive promoter analysis. The mRTVP-1 protein has 255 amino acids and differs from the human RTVP-1 (hRTVP-1) protein by two short in-frame deletions of two and nine amino acids. RTVP-1 mRNA was induced in multiple cancer cell lines by adenovirus-mediated delivery of p53 and by gamma irradiation or doxorubicin both in the presence and in the absence of endogenous p53.