RESUMEN
The dysregulation of long non-coding RNAs (lncRNAs) are involved in regulating tumor progression in multiple manner. However, little is known about whether lncRNA is involved in the translation regulation of proteins. Here, we identified that the suppressor of inflammatory macrophage apoptosis lncRNA (SIMALR) was highly expressed in nasopharyngeal carcinoma (NPC) tissues by analyzing the lncRNA microarray. Clinically, the high expression of SIMALR served as an independent predictor for inferior prognosis in NPC patients. SIMALR functioned as an oncogenic lncRNA that promoted the proliferation and metastasis of NPC cells in vitro and in vivo. Mechanistically, SIMALR served as a critical accelerator of protein synthesis by binding to eEF1A2 (eukaryotic translation elongation factor 1 alpha 2), one of the most crucial regulators in the translation machinery of the eukaryotic cells, and enhancing its endogenous GTPase activity. Furthermore, SIMALR mediated the activation of eEF1A2 phosphorylation to accelerate the translation of ITGB4/ITGA6, ultimately promoting the malignant phenotype of NPC cells. In addition, N-acetyltransferase 10 (NAT10) enhanced the stability of SIMALR and caused its overexpression in NPC through the N4-acetylcytidine (ac4C) modification. In sum, our results illustrate SIMALR functions as an accelerator for protein translation and highlight the oncogenic role of NAT10-SIMALR-eEF1A2-ITGB4/6 axis in NPC.
RESUMEN
Although messenger RNA translation is tightly regulated to preserve protein synthesis and cellular homeostasis, chronic exposure to interferon-γ (IFN-γ) in several cancers can lead to tryptophan (Trp) shortage via the indoleamine-2,3-dioxygenase (IDO)- kynurenine pathway and therefore promotes the production of aberrant peptides by ribosomal frameshifting and tryptophan-to-phenylalanine (W>F) codon reassignment events (substitutants) specifically at Trp codons. However, the effect of Trp depletion on the generation of aberrant peptides by ribosomal mistranslation in gastric cancer (GC) is still obscure. Here, it is shows that the abundant infiltrating lymphocytes in EBV-positive GC continuously secreted IFN-γ, upregulated IDO1 expression, leading to Trp shortage and the induction of W>F substitutants. Intriguingly, the production of W>F substitutants in EBV-positive GC is linked to antigen presentation and the activation of the mTOR/eIF4E signaling pathway. Inhibiting either the mTOR/eIF4E pathway or EIF4E expression counteracted the production and antigen presentation of W>F substitutants. Thus, the mTOR/eIF4E pathway exposed the vulnerability of gastric cancer by accelerating the production of aberrant peptides and boosting immune activation through W>F substitutant events. This work proposes that EBV-positive GC patients with mTOR/eIF4E hyperactivation may benefit from anti-tumor immunotherapy.
RESUMEN
BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.
Asunto(s)
Anticuerpos Monoclonales Humanizados , Quimioradioterapia , Quimioterapia de Inducción , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Persona de Mediana Edad , Masculino , Femenino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamiento farmacológico , Adulto , China/epidemiología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimioradioterapia/métodos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anciano , Cisplatino/uso terapéutico , Cisplatino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gemcitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Desoxicitidina/administración & dosificación , Adulto Joven , Adolescente , Supervivencia sin ProgresiónRESUMEN
Chemoresistance is a main reason for treatment failure in patients with nasopharyngeal carcinoma, but the exact regulatory mechanism underlying chemoresistance in nasopharyngeal carcinoma remains to be elucidated. Here, we identify PJA1 as a key E3 ubiquitin ligase involved in nasopharyngeal carcinoma chemoresistance that is highly expressed in nasopharyngeal carcinoma patients with nonresponse to docetaxel-cisplatin-5-fluorouracil induction chemotherapy. We find that PJA1 facilitates docetaxel resistance by inhibiting GSDME-mediated pyroptosis in nasopharyngeal carcinoma cells. Mechanistically, PJA1 promotes the degradation of the mitochondrial protein PGAM5 by increasing its K48-linked ubiquitination at K88, which further facilitates DRP1 phosphorylation at S637 and reduced mitochondrial reactive oxygen species production, resulting in suppression of GSDME-mediated pyroptosis and the antitumour immune response. PGAM5 knockdown fully restores the docetaxel sensitization effect of PJA1 knockdown. Moreover, pharmacological targeting of PJA1 with the small molecule inhibitor RTA402 enhances the docetaxel sensitivity of nasopharyngeal carcinoma in vitro and in vivo. Clinically, high PJA1 expression indicates inferior survival and poor clinical efficacy of TPF IC in nasopharyngeal carcinoma patients. Our study emphasizes the essential role of E3 ligases in regulating chemoresistance and provides therapeutic strategies for nasopharyngeal carcinoma based on targeting the ubiquitin-proteasome system.
Asunto(s)
Docetaxel , Resistencia a Antineoplásicos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Piroptosis , Ubiquitina-Proteína Ligasas , Ubiquitinación , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Cisplatino/farmacología , Cisplatino/uso terapéutico , Docetaxel/farmacología , Docetaxel/uso terapéutico , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Dinaminas/metabolismo , Dinaminas/genética , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Gasderminas , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patología , Fosfoproteínas Fosfatasas/metabolismo , Fosfoproteínas Fosfatasas/genética , Fosforilación/efectos de los fármacos , Piroptosis/efectos de los fármacos , Piroptosis/genética , Especies Reactivas de Oxígeno/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15â¯% of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.
Asunto(s)
ARN Helicasas DEAD-box , Desoxicitidina , Gemcitabina , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , ARN Largo no Codificante , Animales , Humanos , Antimetabolitos Antineoplásicos/farmacología , Antimetabolitos Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ubiquitinación/efectos de los fármacosRESUMEN
In the original publication [...].