Abstract

<div>Abstract<p><b>Purpose:</b> Nasopharyngeal carcinoma (NPC) is the most common head and neck cancer in Southeast Asia. Because local recurrence and distant metastasis are still the main causes of NPC treatment failure, it is urgent to identify new tumor markers and therapeutic targets for advanced NPC.</p><p><b>Experimental Design:</b> RNA sequencing (RNA-seq) was applied to look for interchromosome translocation in NPC. PCR, FISH, and immunoprecipitation were used to examine the fusion gene expression at RNA, DNA, and protein levels in NPC biopsies. MTT assay, colony formation assay, sphere formation assay, co-immunoprecipitation, chromatin immunoprecipitation assay, and <i>in vivo</i> chemoresistance assay were applied to explore the function of <i>RARS-MAD1L1</i> in NPC.</p><p><b>Results:</b> We demonstrated that <i>RARS-MAD1L1</i> was present in 10.03% (35/349) primary NPC biopsies and 10.7% (9/84) in head and neck cancer (HNC) samples. RARS-MAD1L1 overexpression increased cell proliferation, colony formation, and tumorigenicity <i>in vitro</i>, and the silencing of endogenous RARS-MAD1L1 reduced cancer cell growth and colony formation <i>in vitro</i>. In addition, RARS-MAD1L1 increased the side population (SP) ratio and induced chemo- and radioresistance. Furthermore RARS-MAD1L1 interacted with AIMP2, which resulted in activation of FUBP1/c-Myc pathway. The silencing of FUBP1 or the administration of a c-Myc inhibitor abrogated the cancer stem cell (CSC)-like characteristics induced by RARS-MAD1L1. The expression of c-Myc and ABCG2 was higher in <i>RARS-MAD1L1</i>–positive HNC samples than in negative samples.</p><p><b>Conclusions:</b> Our findings indicate that RARS-MAD1L1 might contribute to tumorigenesis, CSC-like properties, and therapeutic resistance, at least in part, through the FUBP1/c-Myc axis, implying that <i>RARS-MAD1L1</i> might serve as an attractive target for therapeutic intervention for NPC. <i>Clin Cancer Res; 24(3); 659–73. ©2017 AACR</i>.</p></div>

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.