RESUMEN
Classâ 1 myosins (Myo1s) were the first unconventional myosins identified and humans have eight known Myo1 isoforms. The Myo1 family is involved in the regulation of gene expression, cytoskeletal rearrangements, delivery of proteins to the cell surface, cell migration and spreading. Thus, the important role of Myo1s in different biological processes is evident. In this study, we have investigated the effects of pentachloropseudilin (PClP), a reversible and allosteric potent inhibitor of Myo1s, on angiogenesis. We demonstrated that treatment of cells with PClP promoted a decrease in the number of vessels. The observed inhibition of angiogenesis is likely to be related to the inhibition of cell proliferation, migration and adhesion, as well as to alteration of the actin cytoskeleton pattern, as shown on a PClP-treated HUVEC cell line. Moreover, we also demonstrated that PClP treatment partially prevented the delivery of integrins to the plasma membrane. Finally, we showed that PClP caused DNA strand breaks, which are probably repaired during the cell cycle arrest in the G1 phase. Taken together, our results suggest that Myo1s participate directly in the angiogenesis process.
Asunto(s)
Citoesqueleto de Actina/efectos de los fármacos , Inhibidores de la Angiogénesis/farmacología , Ciclo Celular/efectos de los fármacos , Hidrocarburos Clorados/farmacología , Integrinas/metabolismo , Pirroles/farmacología , Inhibidores de la Angiogénesis/toxicidad , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hidrocarburos Clorados/toxicidad , Integrinas/genética , Miosina Tipo I/metabolismo , Pirroles/toxicidad , ARN Mensajero/metabolismoRESUMEN
INTRODUCTION: Oncological surgery must follow some fundamental principles to be truly curative, one of which is the resection of the tumor with surgical margins free of neoplasia. In breast cancer, surgery with positive margins should be expanded immediately. There are probably different intensities, between the stages and molecular subtypes of operable breast cancer, of worsening prognosis due to the surgical margin compromised by the neoplasia in women not submitted to the necessary enlargement of the positive surgical margin. MATERIALS AND. METHODS: Seven hundred and forty-seven women with invasive ductal carcinoma of the breast, analyzing anatomical-pathological information, types of surgery, molecular subtypes, and the presence or absence of the surgical margin compromised by neoplasia. RESULTS: Sixty-one (8.2%) patients had positive surgical margin, causing 2.85 times more risk of locoregional relapse compared to negative surgical margin by multivariate analysis. In subgroup analysis, among stages I, II and III, stage II was the most negatively impacted, with those patients presenting 2.42 times more risk of distant metastasis and 4.94 times more risk of locoregional relapses compared to negative surgical margin by multivariate analysis. Among the molecular subtypes, Triple Negative tumors with a positive surgical margin had 3.56 times more risk of death, 4.98 times more risk of distant metastasis and 5.55 times more risk of locoregional relapse compared to negative surgical margin by multivariate analysis. CONCLUSIONS: The positive surgical margin, especially in Stage II and Triple-Negative breast cancer patients negatively impact the patient's evolution, increasing risk of distant metastasis and death.