A 68-year-old man with a 20-year history of hepatitis C and known cirrhosis presents with right upper quadrant pain and early satiety. Vital signs are stable. Ultrasound reveals a 3.5 cm nodule in the right hepatic lobe with arterial-phase enhancement on contrast-enhanced CT. Serum alpha-fetoprotein (AFP) is elevated at 480 ng/mL. The patient meets imaging criteria for hepatocellular carcinoma (HCC). A biopsy shows microscopic vascular invasion. Which of the following molecular alterations best explains the aggressive phenotype with vascular invasion observed in this patient's tumor?

  1. A)Increased HIF-1α stabilization and VEGF upregulation promoting tumor angiogenesis
  2. B)Loss of E-cadherin expression and activation of Wnt/β-catenin signaling driving epithelial-mesenchymal transitionGABARITO
  3. C)TP53 mutations leading to loss of apoptotic capacity and genomic instability
  4. D)MYC amplification causing increased proliferative rate and reduced differentiation
  5. E)EGFR overexpression through integration of hepatitis C viral oncoproteins

Explicação

Loss of E-cadherin and Wnt/β-catenin activation are hallmark features of epithelial-mesenchymal transition (EMT), a critical process enabling vascular invasion and metastatic dissemination in HCC. E-cadherin loss removes cell-cell adhesion constraints, while β... Ver explicação completa e trilha adaptativa →

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