Protein expression of cancer stem cell markers ABCG2, podoplanin, and CD44 predicts early recurrence of oral squamous cell carcinoma: A study from Western India.

Abstract

Objectives: For oral squamous cell carcinoma (OSCC), we are likely at a juncture in clinical management, where the benefits of therapies are beginning to plateau. Therefore, this study investigated the usefulness of adenosine triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG2), podoplanin (PDPN), and cluster of differentiation (CD) 44 (CD44) that may help to identify patients with an aggressive phenotype and predict prognosis precisely.

Materials and methods: The protein expression of ABCG2, PDPN, and CD44 was investigated in 125 OSCC patients using immunohistochemistry and correlated with clinicopathological parameters and disease outcomes. The data were evaluated using the Statistical Package for the Social Sciences (SPSS) software, and P value ≤0.05 was considered significant.

Results: The protein expression of ABCG2, PDPN, and CD44 was noted in 56%, 43%, and 51%, respectively. ABCG2, PDPN, and CD44 show linear correlation with T3/T4 tumors, presence of metastatic lymph nodes (LNs), and advanced-stage disease. Cox multivariate regression analysis for progression-free survival (PFS) demonstrated that in early-stage patients, CD44 at step 1 (P = 0.007) followed by ABCG2 (P = 0.037) at step 2 was associated with reduced PFS. For overall survival (OS), only ABCG2 (P = 0.019) emerged as a potential parameter. Kaplan-Meier curves showed that the combined signature of ABCG2 with PDPN for total patients, and ABCG2 with CD44 for early-stage patients, emerged as more powerful risk predictors for identifying high-risk patients.

Conclusion: Thus, the combined signature of ABCG2 with PDPN and CD44 could be useful in identifying high-risk patients for more aggressive therapy and effective personalized treatment in the future.