CENPN suppresses autophagy and increases paclitaxel resistance in nasopharyngeal carcinoma cells by inhibiting the CREB-VAMP8 signaling axis
Creators: name: Wang, Bin-Ru
name: Han, Ji-Bo
name: Jiang, Yang
name: Xu, Shan
name: Yang, Rui
name: Kong, Yong-Gang
name: Tao, Ze-Zhang
name: Hua, Qing-Quan
name: Zou, You
name: Chen, Shi-Ming
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Immunology
subject: FOS: Clinical medicine
subject: Biological Sciences not elsewhere classified
subject: Cancer
subject: Hematology

description: Chemotherapeutic resistance is one of the most common reasons for poor prognosis of patients with nasopharyngeal carcinoma (NPC). We found that CENPN can promote the growth, proliferation and apoptosis resistance of NPC cells, but its relationship with chemotherapeutic resistance in NPC is unclear. Here we verified that the CENPN expression level in NPC patients was positively correlated with the degree of paclitaxel (PTX) resistance and a poor prognosis through analysis of clinical cases. VAMP8 expression was significantly increased after knockdown of <i>CENPN</i> by transcriptome sequencing. We found in cell experiments that CENPN inhibited macroautophagy/autophagy and VAMP8 expression and significantly increased PTX resistance. Overexpression of <i>CENPN</i> reduced the inhibitory effects of PTX on survival, cell proliferation, cell cycle progression and apoptosis resistance in NPC cells by inhibiting autophagy. In turn, knockdown of <i>CENPN</i> can affect the phenotype of NPC cells by increasing autophagy to achieve PTX sensitization. Sequential knockdown of <i>CENPN</i> and <i>VAMP8</i> reversed the PTX-sensitizing effect of <i>CENPN</i> knockdown alone. Experiments in nude mice confirmed that knockdown of <i>CENPN</i> can increase VAMP8 expression, enhance autophagy and increase the sensitivity of NPC cells to PTX. Mechanistic studies showed that CENPN inhibited the translocation of p-CREB into the nucleus of NPC cells, resulting in the decreased binding of p-CREB to the <i>VAMP8</i> promoter, thereby inhibiting the transcription of <i>VAMP8</i>. These results demonstrate that CENPN may be a marker for predicting chemotherapeutic efficacy and a potential target for inducing chemosensitization to agents such as PTX. <b>Abbreviations:</b> 3-MA: 3-methyladenine; ATG5: autophagy related 5; CENPN: centromere protein N; CQ: chloroquine; CREB: cAMP responsive element binding protein; ChIP: chromatin immunoprecipitation assay; IC50: half-maximal inhibitory concentration; LAMP2A: lysosomal associated membrane protein 2A; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; NPC: nasopharyngeal carcinoma; NPG: nasopharyngitis; oe<i>CENPN</i>: overexpressed <i>CENPN</i>; PTX: paclitaxel; RAPA: rapamycin; RNA-seq: transcriptome sequencing; sh<i>CENPN</i>: small hairpin RNA expression vector targeting the human <i>CENPN</i> gene; sh<i>CENPN</i>-sh<i>VAMP8</i>: sequential knockdown targeting the human <i>CENPN</i> gene and <i>VAMP8</i> gene; sh<i>VAMP8</i>: small hairpin RNA expression vector targeting the human <i>VAMP8</i> gene; TEM: transmission electron microscopy; TIR: tumor inhibitory rate; VAMP8: vesicle associated membrane protein 8.