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Published on: June 26, 2019
Exploring MFSD9: From Expression Patterns to Therapeutic Implications in LUAD
Qian Wang1, Meijuan Zhang2, Yan Xiang1
1Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
Introduction:
This study explores the role of Major Facilitator Superfamily Domain-containing Protein 9 (MFSD9) in lung adenocarcinoma (LUAD) using bioinformatics and experimental validation, aiming to identify its potential as a biomarker and therapeutic target.
Methods:
Comprehensive analysis of MFSD9 expression across cancers, particularly LUAD, was carried out using The Cancer Genome Atlas (TCGA) dataset. Correlations between MFSD9 expression and clinical outcomes, immune infiltration, immune checkpoint genes, tumor mutational burden (TMB), microsatellite instability (MSI), mRNA expression-stemness index (mRNAsi), and drug sensitivity were examined. Validation was performed using the Human Protein Atlas (HPA), Gene Expression Omnibus (GEO) databases, and qRT-PCR in LUAD cell lines.
Results:
MFSD9 was significantly overexpressed in LUAD, correlating with reduced overall survival (OS) and progression-free survival (PFS) (p = 0.044 and p = 0.026, respectively). It was found to be an independent prognosis factor (p = 0.046). MFSD9 expression was associated with immune cell infiltration, immune checkpoint genes, TMB, MSI, and mRNAsi, and inversely correlated with sensitivity to certain drugs, including zygosporin A and lovastatin.
Discussion:
MFSD9 shows promise as a prognostic biomarker and therapeutic target in LUAD. Its role in immune modulation and tumor progression highlights its potential for immunotherapy. However, further experimental validation is needed to address study limitations.
Conclusion:
MFSD9 is a potential biomarker and therapeutic target in LUAD, with significant implications for prognosis and treatment response. Future studies should focus on functional validation and clinical application.

