RESUMEN
The mechanisms by which prostate cancer shifts from an indolent castration-sensitive phenotype to lethal castration-resistant prostate cancer (CRPC) are poorly understood. Identification of clinically relevant genetic alterations leading to CRPC may reveal potential vulnerabilities for cancer therapy. Here we find that CUB domain-containing protein 1 (CDCP1), a transmembrane protein that acts as a substrate for SRC family kinases (SFKs), is overexpressed in a subset of CRPC. Notably, CDCP1 cooperates with the loss of the tumor suppressor gene PTEN to promote the emergence of metastatic prostate cancer. Mechanistically, we find that androgens suppress CDCP1 expression and that androgen deprivation in combination with loss of PTEN promotes the upregulation of CDCP1 and the subsequent activation of the SRC/MAPK pathway. Moreover, we demonstrate that anti-CDCP1 immunoliposomes (anti-CDCP1 ILs) loaded with chemotherapy suppress prostate cancer growth when administered in combination with enzalutamide. Thus, our study identifies CDCP1 as a powerful driver of prostate cancer progression and uncovers different potential therapeutic strategies for the treatment of metastatic prostate tumors.
Asunto(s)
Antígenos de Neoplasias/biosíntesis , Moléculas de Adhesión Celular/biosíntesis , Regulación Neoplásica de la Expresión Génica , Sistema de Señalización de MAP Quinasas , Neoplasias de la Próstata/metabolismo , Regulación hacia Arriba , Animales , Antígenos de Neoplasias/genética , Benzamidas , Moléculas de Adhesión Celular/genética , Línea Celular Tumoral , Drosophila melanogaster , Humanos , Liposomas , Masculino , Nitrilos , Fosfohidrolasa PTEN/biosíntesis , Fosfohidrolasa PTEN/genética , Feniltiohidantoína/análogos & derivados , Feniltiohidantoína/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patologíaRESUMEN
Salmon calcitonin (sCT) is characterized by a poor oral availability. A new copolymer, ß-poly(N-2-hydroxyethyl)-graft-{N-2-ethylene[2-poly(methacrylic acid sodium salt)isobutyrate]}-d,l-aspartamide (PHEA-IB-p(MANa(+))), was designed for the oral administration of sCT through the formation of supramolecular aggregates (SAs) based on electrostatic interactions. Several sCT/PHEA-IB-p(MANa(+)) weight ratios were characterized by turbidimetry, DLS, zeta potential, and microscopy analysis. After the incubation of sCT/PHEA-IB-p(MANa(+)) complex with digestive enzymes, 10% (w/w) of loaded sCT was released in the native form. In vitro investigation was carried out to determine the copolymer effect on the permeability of sCT in Caco-2 cell monolayers. sCT pharmacokinetic profile and the pharmacodynamic effect on calcium plasma level were determined following an oral administration of the lead sCT/PHEA-IB-p(MANa(+)) SA (1/5 ratio) in rats. The SA yielded a marked prolongation of the sCT lowering calcium effect. The maximum decrease, 35% with respect the basal calcium plasma level at time 0 h, was achieved after 4h post-administration, and after 7 h, a decrease of 20% was still present. Differently, sCT yielded a transient calcium decrease that was completely restored after 5h. The higher bioavailability of sCT administered as SA was confirmed by the pharmacokinetic studies. In fact, the AUC and the Cmax were about 15 times higher for the sCT formulated as SA than the free sCT. This study indicates the potentials of PHEA-IB-p(MANa(+)) as carrier of sCT for oral delivery.