Identification and characterization of Karyopherin α2 (KPNA2), a member of the nucleocytoplasmic transporter family, in lung cancer

Abstract

Introduction: Many oncologists began to make sense, that the Karyopherin a-2 (KPNA2), a nucleocytoplasmic transport protein, regulates the nuclear import of macromolecules and changes in cellular phenotype. In particular, it can be a poor prognostic marker by causing aberrant subcellular localization of DNA damage response proteins or OCT4-c MYC pathway molecules depending on the type of carcinoma. An association with the p53 oncogenic pathway has been reported, showing good prognostic values in other types. We aimed to investigate the clinical significance and metabolic pathway of stable CAF and cancer cells for KPNA2 Method: We retrospectively analyzed the data from NSCLC patients receiving curative resection in Uijeongbu and Bucheon St. Mary’s Hospitals (n=165). IHC staining was performed on the tumor microarray samples using antibodies against KPNA2. The positivity was defined as median value of H-score. Result: Based on the TMA staining, mean KPNA2 score was 36.5 [0-240] and median value was 10. Table 1. Scatter plots and correlation between KPNA2 expression levels and tumor invasiveness markers reveals that high KPNA2 expressor was related to lymphatic invasion (p = 0.00782), advanced stage (p = 0.0202) and current smoker (p = 0.0074). KPNA2 expression was higher in squamous cell carcinoma(SqCC) histotype than in adenocarcinoma (SqCC ratio (%), 13.5 vs 43.4 in Low exp vs High exp; p = 0.007). Patients with high expression of KPNA2 showed shorter survival than other patients (median OS (mo), 72.8 vs 42.2, P < 0.0001; median RFS (mo), 72.8 vs 32.1, P < 0.0011) and relevant to high recurrence (recurrence rate (%), 24.7 vs 44.7, p = 0.007). Conclusion: Taken together, our results suggest that KPNA2 protein expression has a poor prognostic association, revealed by its association with survival outcome or invasiveness markers. Its clinical significance as an oncogenic target molecule is emerging, and further evaluation using an organoid model is in progress.