Axl and autophagy LC3 expression in tumors is strongly associated with clinical prognosis of hepatocellular carcinoma patients after curative resection

Abstract

Background The role of Axl and LC3 as predictors of tumor recurrence and overall survival (OS) after hepatocellular carcinoma (HCC) resection remains unclear. Methods We retrospectively included 535 HCC patients who underwent hepatectomy from 2010 to 2014 in this study. Axl and the autophagy-related marker LC3 were immunohistochemically assessed in tumors. Results Axl expression was significantly associated with advanced clinicopathological features, including cirrhosis, microvascular invasion, macrovascular invasion, tumor size, BCLC stage, recurrence, and mortality. HCC recurrence occurred in 245 patients, and 219 patients died. The 5-year cumulative incidences of HCC recurrence and OS rate after HCC resection were 53.3% and 58.8%, respectively. In the Cox proportional analyses, high Axl expression and high LC3 expression were significantly associated with HCC recurrence (hazard ratio [HR]: 3.85, 95% confidence interval [CI]: 2.95-5.02, P < 0.001; and HR: 0.38, 95% CI: 0.26-0.55, P < 0.001, respectively). In addition, HCC recurrence (HR: 2.87, 95% CI: 2.01-4.01, P < 0.0001), microvascular invasion (HR: 1.85, 95% CI: 1.08-3.19, P = 0.026), hepatitis B virus-related HCC (HR: 1.77, 95% CI: 1. 21-2.56, P = 0.003), high Axl expression (HR: 1.66, 95% CI: 1.41-1.97, P < 0.0001), antiviral therapy (HR: 0.54, CI: 0.38-0.76, P < 0.001) and LC3 expression (HR: 0.41, 95% CI: 0.28-0.58, P < 0.001) were significantly associated with mortality. Furthermore, patients with a combination of high Axl and low LC3 expression had the highest risk of HCC recurrence (HR: 6.53, 95% CI: 4.11-10.4, P < 0.001) and mortality (HR: 6.66, 95% CI: 4.07-10.9, P < 0.001). In patients with high Axl, low LC3, and combined high Axl and low LC3 expression, the 5-year cumulative incidences of HCC recurrence and OS rate were 77.9%, 73.3%, and 90.0% and 28.8%, 26.7%, and 16.8%, respectively. Conclusion High Axl expression in tumors is associated with aggressive tumor behavior and worse clinical outcomes. Furthermore, the combination of high Axl and low LC3 expression significantly predicts poorer prognosis for HCC patients who underwent hepatectomy.