Project description:The development of therapeutic resistance and metastatic dissemination takes place in 20-30% patients with nasopharyngeal carcinoma (NPC), resulting in poor survival. Hence, a better understanding of the underlying molecular mechanisms will help improve clinical outcome. We have identified a novel circRNA, circIPO7, as a promoter of metastasis and cisplatin chemoresistance in NPC cells. High-throughput RNA sequencing analysis was performed in the human nasopharyngeal carcinoma cell line S18 after transfection with control siRNA or circIPO7 siRNA.
Project description:Radiotherapy and adjuvant cisplatin (DDP) chemotherapy are standard administrations applied in the treatment of NPC. However, molecular change and functions of DDP chemo-resistance in nasopharyngeal carcinoma are still poorly understood.
Project description:Despite the docectaxel-cisplatin-5-fluorouracil (TPF) induction chemotherapy has greatly improved the patients' survival and became the standard of care for advanced nasopharyngeal carcinoma (NPC), some patients could not benefit from this therapy. The mechanism underlying the TPF chemoresistance remains unclear. Here, we identified ATMIN as a chemoresistance gene in response to TPF therapy in NPC patients. We found that USP10 deubiquitinates and stabilizes ATMIN protein. Knockdown of ATMIN inhibits the cell proliferation and facilitates the docetaxel-sensitivity of NPC cells in vitro and in vivo. Mechanistically, RNA-seq combined with ChIP-seq analysis suggests that ATMIN is associated with the cell death signaling. ATMIN transcriptionally activates LCK to facilitate cell proliferation and docetaxel-resistance. Our findings broaden the insight into the mechanism of chemoresistance in NPC and the USP10-ATMIN-LCK axis provides potential therapeutic targets for the management of NPC.
Project description:The development of therapeutic resistance and metastatic dissemination takes place in 20-30% patients with nasopharyngeal carcinoma (NPC), resulting in poor survival. Hence, a better understanding of the underlying molecular mechanisms will help improve clinical outcome. We have identified a novel circRNA, circIPO7, as a promoter of metastasis and cisplatin chemoresistance in NPC cells. circIPO7 was found to bind to YBX1. Genome binding/occupancy profiling by high throughput sequencing were performed to explore the underlying molecular mechanisms.
Project description:Despite the docectaxel-cisplatin-5-fluorouracil (TPF) induction chemotherapy has greatly improved the patients' survival and became the standard of care for advanced nasopharyngeal carcinoma (NPC), some patients could not benefit from this therapy. The mechanism underlying the TPF chemoresistance remains unclear. Here, we identified ATMIN as a chemoresistance gene in response to TPF therapy in NPC patients. We found that USP10 deubiquitinates and stabilizes ATMIN protein. Knockdown of ATMIN inhibits the cell proliferation and facilitates the docetaxel-sensitivity of NPC cells in vitro and in vivo. Mechanistically, RNA-seq combined with ChIP-seq analysis suggests that ATMIN is associated with the cell death signaling. ATMIN transcriptionally activates LCK to facilitate cell proliferation and docetaxel-resistance. Our findings broaden the insight into the mechanism of chemoresistance in NPC and the USP10-ATMIN-LCK axis provides potential therapeutic targets for the management of NPC.
Project description:Heterozygous p53-R280T mutations frequently occur in many nasopharyngeal carcinoma cell lines and nasopharyngeal carcinoma patients. However, the role of this mutation in the progression of nasopharyngeal carcinoma remains unclear. In this study, we successfully generated the tp53 knockout nasopharyngeal carcinoma (NPC) cells by CRISPR/Cas9-mediated genome editing and found that knockout of heterozygous tp53-R280T inhibited the proliferation of NPC cells significantly in vivo and in vitro. Mechanistic analyses indicated that heterozygous p53-R280T can activate the PI3K/Akt Signaling pathway in NPC cells. In conclusion, our findings provide a mechanistic insight into the role of heterozygous p53-R280T in NPC progression.
Project description:MicroRNAs are biomarkers of prognosis and survival for many types of cancer. We evaluated whether microRNAs can predict the survival and efficacy of concurrent chemotherapy in nasopharyngeal carcinoma (NPC) patients. We retrospectively analyzed microRNA expression in 312 paraffin-embedded NPC specimens and 18 normal nasopharyngeal tissues using microarray. We found Forty-one microRNAs are differentially expressed between NPC and normal tissues, and a five-microRNA signature can predict survival independent of stage. NPC patients with the low-risk microRNA signature have a favorable response to concurrent chemotherapy. microRNA profiling of nasopharyngeal carcinoma tissues vs. normal nasopharyngeal tissues 312 paraffin-embedded nasopharyngeal carcinoma tissues and 18 paraffin-embedded normal nasopharyngeal tissues
Project description:Nasopharyngeal carcinoma (NPC) is among a small number of solid tumors that are caused by the Epstein-Barr virus (EBV). Recently, BH3 mimetics, a novel class of drugs that inhibit pro-survival proteins of the BCL-2 family, have demonstrated clinical anti-cancer efficacy in hematological malignancies and are being investigated for use in solid tumors. There is known dysregulation of pro-survival pathways, particularly, the intrinsic apoptotic pathway during EBV infection of B cells suggesting NPC may be driven by the same pathways, and thus sensitive to BH3 inhibition. Using immunohistochemistry, we examined the expression of BCL-2 family of proteins (BCL2, MCL1 and BCLxL) in 174 NPC from patients treated with curative intent as well as five NPC cell lines. We subsequently evaluated the anti-tumor efficacy of three BH3 mimetics (ABT-199, ABT-737 and S63845) in NPC cells alone or in combination with cisplatin, a commonly used cytotoxic agent in NPC treatment. BCL-2 was highly expressed in NPC tumors and cells. Despite this, BCL2 inhibition, or BH3 monotherapy was not effective. However, marked sensitivity was observed with the combination S63845 (targeting MCL-1) and cisplatin in NPC43, which had high expression of MCL-1. This combination resulted in upregulation of pro-apoptotic tBID suggesting a priming role of cisplatin and apoptotic potentiation through MCL-1 inhibition. Flow cytometry studies and RNA sequencing of NPC43 cells treated with the combination of cisplatin with S63845 and untreated cells showed death by apoptosis and upregulation in stress response and DNA damage pathways. Our study suggests that combining BH3 mimetics with cisplatin could be an effective treatment strategy for NPC and warrants further investigation