RESUMO
The p53-related transcription factor p63 is required for maintenance of epithelial cell differentiation. We found that activated forms of the Harvey Rat Sarcoma Virus GTPase (H-RAS) and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) oncogenes strongly repress expression of ∆Np63α, the predominant p63 isoform in basal mammary epithelial cells. This regulation occurs at the transcriptional level, and a short region of the ∆Np63 promoter is sufficient for repression induced by H-RasV12. The suppression of ∆Np63α expression by these oncogenes concomitantly leads to an epithelial-to-mesenchymal transition (EMT). In addition, the depletion of ∆Np63α alone is sufficient to induce EMT. Both H-RasV12 expression and ∆Np63α depletion induce individual cell invasion in a 3D collagen gel in vitro system, thereby demonstrating how Ras can drive the mammary epithelial cell state toward greater invasive ability. Together, these results suggest a pathway by which RAS and PIK3CA oncogenes induce EMT through regulation of ∆Np63α.
Assuntos
Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação da Expressão Gênica , Mutação , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Proteínas ras/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Genes Reporter , Humanos , Modelos Biológicos , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Deleção de Sequência , Transdução de Sinais , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismoRESUMO
Combination of venoarterial extracorporeal membrane oxygenation (VA-ECMO) and a percutaneous microaxial left ventricular assist device (pLVAD), or "EC-VAD," has been reported in cases of left ventricular decompression with mixed results. We conducted a retrospective review of patients who received EC-VAD (n = 29) or isolated VA-ECMO therapy (ECMO-only; n = 196) for refractory cardiogenic shock between February 2011 and October 2014. Fourteen patients received VA-ECMO and then Impella pLVAD (EâEC-VAD), and 15 received the Impella pump then VA-ECMO (IâEC-VAD). EâEC-VAD patients demonstrated decreased pulmonary artery systolic (36.00 ± 16.84 mm Hg versus 30.63 ± 12.13 mm Hg; p = 0.049) and diastolic (24.25 ± 13.45 mm Hg versus 17.25 ± 7.96 mm Hg, p = 0.049) pressures by 24 hours post-EC-VAD implant. In the same period, IâEC-VAD patients demonstrated improved SvO2 (43.14 ± 16.75% versus 75.18 ± 13.88%, p = 0.043) and PaO2/FiO2 ratio (148.55 ± 67.69 mm Hg versus 374.51 ± 170.97 mm Hg, p = 0.043). Thirty-day survival rates were 42.9% in EâEC-VAD, 46.7% in IâEC-VAD, and 49.0% in ECMO-only (p = 0.913). Hemolysis occurred more in EC-VAD patients (44.83% versus 17.35% in ECMO-only, p = 0.002); however, there was no increased frequency of other adverse events including bleeding and lower limb ischemia. Despite increased hemolysis, combined use of VA-ECMO and pLVAD may improve or circumvent left ventricular distension in refractory cardiogenic shock while promoting adequate blood flow.