ALTERED CELL SECRETOME REVEALS HEME OXYGENASE 1 AS A MODULATOR OF BONE PROGENITOR AND PROSTATE TUMOR CELL INTERACTIONS

ALEJANDRA PAEZ,; NICOLAS ANSELMINO; EMILIANO ORTIZ,; MARIA PIA VALACCO; JAVIER COTIGNOLA ; ELBA VAZQUEZ.; GUERON GERALDINE

CABA

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Sociedad Argentina de Investigación Clínica (SAIC)

Abstract: Prostate Cancer (PCa) is the second leading type of cancerin men. PCa cells display abnormalities in their adhesive properties,which result in an augmented capacity to resist chemotherapyand colonize other organs such as bone. Heme Oxygenase-1 (HO-1)acts as a cellular rheostat counteracting oxidative and inflammatorydamage. We previously showed that HO-1 over-expression impairstumor growth and angiogenesis in vivo. Given that inflammation iscritical for the development and progression of PCa and that boneis the most common homing organ for PCa metastases, we used aco-culture transwell system for tumoral and bone progenitor cellsand quantified filopodia structures at the leading edge of PCa cells.Briefly, PC3 cells pre-treated or not with hemin (potent inducer ofHO-1; 50uM, 24h) were co-cultured with the murine MC3T3 or RAW264.7 cells for 24h. Conditioned media (CMs) were collected andadded to new PC3 cultures for 24h.Results show that the CM from PC3/MC3T3 or PC3/RAW264.7co-cultures, have a negative impact both in the number of filopodiaper cell and contacts among them. However, hemin pre-treatment ofPC3 cells prior to co-culture, prevented the reduction in the numberof filopodia and cell contacts.High-throughput secretomic analysis of CMs (nanoLC-MS/MS(Orbitrap)identified more than 30 proteins differentially released, in theCMs, of note: cadherins, collagen and critical proteins associated tocell detachment. Interestingly, the bioinformatics screening for thesecytoskeletal-related proteins showed a significant misregulation inprostate adenocarcinoma compared to normal tissue.Altogether, our findings demonstrate that HO1modulation in PCacells in co-culture with bone progenitor cells induces the release ofkey cytoskeleton-regulating proteins that impact on cell morp