RESUMEN
The tumor microenvironment is fundamental to cancer progression, and the influence of its mechanical properties is increasingly being appreciated. Tamoxifen has been used for many years to treat estrogen-positive breast cancer. Here we report that tamoxifen regulates the level and activity of collagen cross-linking and degradative enzymes, and hence the organization of the extracellular matrix, via a mechanism involving both the G protein-coupled estrogen receptor (GPER) and hypoxia-inducible factor-1 alpha (HIF-1A). We show that tamoxifen reduces HIF-1A levels by suppressing myosin-dependent contractility and matrix stiffness mechanosensing. Tamoxifen also downregulates hypoxia-regulated genes and increases vascularization in PDAC tissues. Our findings implicate the GPER/HIF-1A axis as a master regulator of peri-tumoral stromal remodeling and the fibrovascular tumor microenvironment and offer a paradigm shift for tamoxifen from a well-established drug in breast cancer hormonal therapy to an alternative candidate for stromal targeting strategies in PDAC and possibly other cancers.
Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Receptores de Estrógenos/genética , Receptores Acoplados a Proteínas G/genética , Tamoxifeno/administración & dosificación , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Reprogramación Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Miosinas/genética , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Transducción de Señal/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacosRESUMEN
Nontargeted single-cell proteomics analysis by mass spectrometry with sample multiplexing utilizing isobaric labeling is often performed using a carrier proteome. The presented protocol describes a targeted approach that replaces the carrier proteome with a set of synthetic peptides from selected proteins, which improves the identification and quantification of these proteins in single human cells.