Expression and clinical significance of organic cation transporter family in glioblastoma multiforme

Background Solute carrier (SLC) 22 A1, A2, and A3 are polyspecific transporters transporting organic cations like histamine, serotonin, norepinephrine, dopamine, MPP + , and toxins. The expression of SLC22A1–A3 in cancer is seldom investigated, and the function of SLC22A1–A3 in glioblastoma multiforme (GBM) is never elucidated. Materials In our study, we detected the expression of SLC22A1–A3 in 11 fresh GBMs and tumor-adjacent brain tissues with qPCR, and in 129 paraffin-embedded GBMs with immunohistochemistry (IHC). With chi-square test, we investigated the correlation between expression of SLC22A1–A3 and the clinicopathological factors including patients’ age, sex, tumor size, and KPS score. With Kaplan–Meier method and Cox-regression model, we estimated the prognostic significance of SLC22A1–A3 in GBM. Results SLC22A3 was significantly downregulated in GBMs compared with the tumor-adjacent normal tissues. With univariate survival analyses, we showed that SLC22A3, instead of SLC22A1 and A2, was an independent biomarker predicting favorable prognosis. With multivariate analyses, SLC22A3 was identified as an independent prognostic biomarker indicating the favorable outcome of GBM. Conclusions SLC22A3 is an independent favorable prognostic biomarker of GBM. Patients with low SLC22A3 may be more high-risk and should receive more intensive post-operational supervision and treatments.