ObjectivesTo meet the demand for personalized treatment, effective stratification of patients with metastatic nasopharyngeal carcinoma (mNPC) is essential. Hence, our study aimed to establish an M1 subdivision for prognostic prediction and treatment planning in patients with mNPC.Materials and methodsThis study included 1239 patients with mNPC from three medical centers divided into the synchronous mNPC cohort (smNPC, n = 556) to establish an M1 stage subdivision and the metachronous mNPC cohort (mmNPC, n = 683) to validate this subdivision. The primary endpoint was overall survival. Univariate and multivariate Cox analyses identified covariates for the decision-tree model, proposing an M1 subdivision. Model performance was evaluated using time-dependent receiver operating characteristic curves, Harrell’s concordance index, calibration plots, and decision curve analyses.ResultsThe proposed M1 subdivisions were M1a (≤5 metastatic lesions), M1b (>5 metastatic lesions + absent liver metastases), and M1c (>5 metastatic lesions + existing liver metastases) with median OS of 34, 22, and 13 months, respectively (p < 0.001). This M1 subdivision demonstrated superior discrimination (C-index = 0.698; 3-year AUC = 0.707) and clinical utility over those of existing staging systems. Calibration curves exhibited satisfactory agreement between predictions and actual observations. Internal and mmNPC cohort validation confirmed the robustness. Survival benefits from local metastatic treatment were observed in M1a, while immunotherapy improved survival in patients with M1b and M1c disease.ConclusionThis novel M1 staging strategy provides a refined approach for prognostic prediction and treatment planning in patients with mNPC, emphasizing the potential benefits of local and immunotherapeutic interventions based on individualized risk stratification.

Objective:To determine the safety of prophylactic irradiation dose CTV 60Gy optimized to CTV 50Gy for II b region in patients with stage N 0-N 1 nasopharyngeal carcinoma (NPC) and the dose advantage and clinical value for parotid gland protection, and to understand the diagnostic value of PET-CT and diffusion-weighted imaging (DWI) for suspicious positive lymph nodes in the neck (5 mm≤maximum short diameter<10 mm). Methods:Clinical data of 157 patients with primary non-metastatic NPC (N 0-N 1) admitted to our hospital from June 2015 to March 2017 were retrospectively analyzed. 104 patients underwent II b clinical target volume optimization guided by multimodal imaging system. Survival analysis was performed by Kaplan - Meier method. Univariate/multivariate regression analysis was performed to analyze the pattern of cervical lymph node recurrence. Paired t-test was used to compare the differences in target volume and parotid gland dose parameters before and after dose optimization. Results:Sixty patients underwent single-neck optimization in stage N 1, 25 patients received double-neck optimization (only those with retropharyngeal lymph node metastasis), and 19 patients underwent double-neck optimization in stage N 0. Three patients had cervical regional recurrence, all in-field. The 5-year overall survival rate was 93.3%. The lymph node recurrence-free survival rate, local recurrence-free survival rate, distant metastasis-free survival rate and disease-free survival rate were 97.1%, 91.3%, 88.5% and 80.8%, respectively. Cervical lymph node recurrence was associated with local recurrence in the nasopharynx, regardless of retropharyngeal lymph node status. Fourteen patients had suspicious positive cervical lymph nodes in II b region, with a mean maximum short diameter of 7.1 (5~9) mm on the largest cross-sectional plane, and 11 of them were positive on PET-CT, with a mean SUV max of 2.96 (2.5~3.3). There was no significant difference in GTV after optimization ( P>0.05). D mean, D max, D 50% and V 26Gy of parotid gland were significantly lower than those of conventional plan (all P<0.01). Conclusions:It is safe to optimize CTV 60Gy to CTV 50Gy in II b region in patients with N 0-N 1 NPC, and the exposure dose to normal tissues around the parotid gland and neck is significantly reduced. For small lymph nodes that do not meet the diagnostic criteria, it needs to be individualized in combination with multimodality imaging systems, such as PET-CT and DWI.

Background: In recent years, the development of high-throughput sequencing technology has promoted the rapid development of circRNA-related research. Studies have found that circRNA plays a key role in a variety of tumors, but few people study the role of circRNA in nasopharyngeal carcinoma. Under comprehensive treatments, the 5-year survival rate can reach about 70%, but some patients still have distant metastases or recurrences after treatment. Therefore, it is very important to study the molecular mechanisms of the proliferation and invasion of nasopharyngeal carcinoma. Methods: QRT-PCR was applied to detect the relative expression level of circFOXM1 in NPC and nasopharyngeal epithelial cell lines. We knocked down circFOXM1 and studied the influence of circFOXM1 on NPC cells. Nuclear and cytoplasmic RNA isolation experiments, fluorescence in situ hybridization (FISH), bioinformatics analysis, the dual-luciferase reporter experiment, Western Blot, and other experiments were conducted to verify the relationships among circFOXM1, miR-136-5p, and SMAD2. We collected clinical NPC samples to prove the effect of circFOXM1 on the prognosis and treatment of NPC. Results: In this study, we found that circFOXM1 is highly expressed in nasopharyngeal carcinoma tissue cells compared with adjacent normal tissues and is related to the staging of nasopharyngeal carcinoma. High expression of circFOXM1 indicates a poor prognosis for nasopharyngeal carcinoma. Knockdown of CircFOXM1 inhibited the proliferation and invasion of nasopharyngeal carcinoma cells. Conclusion: CircFOXM1 promotes the malignant proliferation of nasopharyngeal carcinoma cells by regulating the miR-136-5p-SMAD2 axis.

Kinesin family member 18A (KIF18A) is significantly overexpressed and is related to the poor prognosis of human cancers. However, the function of KIF18A in esophageal cancer (EC) is still unclear. Human EC cell lines were used in this study. KIF18A expression in human tissues was assessed using Gene Expression Profiling Interactive Analysis 2.0 (GEPIA2). The expressions of KIF18A or IGF2BP3 in EC cells were detected using qRT-PCR or WB. Cells were transfected using si-KIF18A, si-IGF2BP3, and plasmid IGF2BP3. The abilities of proliferation, migration, and invasion were detected by EdU, wound-healing, and transwell assay. The interaction between KIF18A and IGF2BP3 was predicted by starBase v3.0 and studied by RIP and RNA stability assay. Colony formation assay was used to reflect the changes of radiosensitivity in EC cells. KIF18A was upregulated in EC, and KIF18A knockdown inhibited EC cell proliferation, migration, invasion, and radioresistance. The prediction in starBase and RIP assay results showed that KIF18A mRNA could bind to IGF2BP3 protein in EC cells. RNA stability assay was performed to confirm that IGF2BP3 affects mRNA stability of KIF18A. Further studies also showed that IGF2BP3 could positively regulate KIF18A on proliferation, migration, invasion, and radioresistance. Our findings first revealed an oncogenic effect of KIF18A in human EC progression. KIF18A expression was associated with radioresistance of EC cells. The binding relationship between KIF18A and IGF2BP3 might influence the mRNA stability of KIF18A in EC cell lines.

放射治疗是肿瘤的重要治疗手段之一,但是也面临着肿瘤放疗抵抗等临床治疗效果不佳的难题.如何提高放射治疗效果,即增强肿瘤的放射敏感性仍待解决.放射治疗是通过放射线对肿瘤细胞DNA直接及间接的损伤,达到治疗肿瘤的目的 .目前,对于DNA损伤修复机制的探讨,以及DNA损伤应答作为放射治疗靶点的研究是肿瘤生物学及放射生物学研究的热点.本文将对DNA损伤修复机制及其与肿瘤放射敏感性关系的近期研究进展作一综述.我们认为,DNA损伤修复基因作为放射增敏相关基因靶点,将会有很好的前景,最终促进肿瘤治疗的进展.

BACKGROUND:Mounting evidence has reported that microRNA-154-5p (miR-154-5p) is involved in the development of multiple cancers, but its function in nasopharyngeal carcinoma (NPC) remains not well investigated.METHODS:Real-time quantitative PCR (qRT-PCR) was used to detect miR-154-5p expression in NPC tissues and cells. CCK8, colony formation, wound healing and transwell assays were performed to assess cell proliferation, migration and invasion. Dual-luciferase reporter assays and Western blots were performed to confirm the target gene of miR-154-5p. Rescue experiments were conducted to explore the influence of target gene KIF14 on the functions of miR-154-5p. Xenograft tumor model was conducted to detect the effect of miR-154-5p in vivo.RESULTS:qRT-PCR results revealed that the expression of miR-154-5p was down-regulated in NPC tissues and cell lines compared to normal nasopharyngeal tissues and cell line. Overexpression of miR-154-5p inhibited cell migration and invasion. However, miR-154-5p had no influence on the proliferation of NPC cells. MiR-154-5p overexpression suppressed xenograft tumor metastasis in vivo. Dual-luciferase reporter analysis identified KIF14 as a target gene of miR-154-5p. Rescue experiments showed that knockdown of KIF14 reversed the effect of inhibiting miR-154-5p expression on NPC cell migration and invasion.CONCLUSION:Taken together, miR-154-5p suppresses tumor migration and invasion by targeting KIF14 in NPC. The newly identified miR-154-5p/KIF14 interaction offers further insights into the progression of NPC, which may represent a novel target for NPC diagnosis and treatment.

Accumulating evidences indicate that circular RNAs (circRNAs), a subclass of noncoding RNAs, play important role in regulating gene expression in eukaryotes. Hsa_circ_0046263 (circ-0046263) was found aberrantly expressed in nasopharyngeal carcinoma (NPC), but its role in tumor growth and metastasis remains largely unclear. Sanger sequencing, RNase R assay, and nucleic acid electrophoresis were conducted to verify the identification of circ-0046263. Nuclear separation and fluorescence in situ hybridization (FISH) assays were used to determine the localization of circ-004263. Dual luciferase reporter and RNA immunoprecipitation (RIP) were employed to confirm the binding of circ-0046263 with miR-133a-5p. Colony formation, proliferation, wound healing, transwell, western blot, and in vivo tumor growth and metastasis assays were performed to assess the roles of circ-0046263, miR-133a-5p, IGFBP3 and their interactions in NPC cells. Circ-0046263 was upregulated in both NPC cell lines and tissues. The in vitro functional studies revealed that knockdown of circ-0046263 inhibited the proliferation, invasion, and migration of NPC cells, whereas its overexpression produced the opposite result. In vivo experiments indicated that knockdown or overexpression of circ-0046263 attenuated or promoted tumor growth and metastasis, respectively. Mechanistically, circ-0046263 could act as a miRNA sponge to absorb miR-133a-5p and upregulate the expression of miRNA downstream target IGFBP3. In addition, miR-133a-5p inhibition or IGFBP3 overexpression could rescue the malignant behavior induced by circ-0046263 silencing. Finally, circ-0046263 plays a tumor-promoting role in NPC to enhance malignant behavior through the miR-133a-5p/IGFBP3 axis, which could be a potential target for NPC therapy.

环状RNA(circRNA)是一类新近发现的调节RNA,具有结构稳定、高度保守及组织特异表达等性质,其长度大小不一,常见数十到数千碱基对.研究显示,circRNA可作为肿瘤基因表达的主要调节因子,常见的作用方式是充当分子海绵吸附微小RNAs (miRNAs)来调节基因的表达,还可以通过直接调节转录和干扰剪接机制来发挥作用,因而与肿瘤的发生发展关系十分密切.虽然与线性对应物相比丰度较低,但它们通常以组织和发育阶段特异性的方式表达,加上共价闭环结构对RNA酶活性的显著抗性,这使得circRNA作为肿瘤和其他疾病的新型生物标志物显示出巨大的应用前景.全文就circRNA形成机制、功能以及与肿瘤的相关性进行综述.

Double-strand breaks (DSBs) are repaired through two major pathways, homology-directed recombination (HDR) and non-homologous end joining (NHEJ). The choice between these two pathways is largely influenced by cell cycle phases. HDR can occur only in S/G2 when sister chromatid can provide homologous templates, whereas NHEJ can take place in all phases of the cell cycle except mitosis. Central to NHEJ repair is the Ku70/80 heterodimer which forms a ring structure that binds DSB ends and serves as a platform to recruit factors involved in NHEJ. Upon completion of NHEJ repair, DNA double strand-encircling Ku dimers have to be removed. The removal depends on ubiquitylation and proteasomal degradation of Ku80 by the ubiquitin E3 ligases RNF8. Here we report that RNF8 is a substrate of APCCdh1 and the latter keeps RNF8 level in check at DSBs to prevent premature turnover of Ku80.

Double-strand breaks (DSBs) are repaired through two major pathways, homology-directed recombination (HDR) and non-homologous end joining (NHEJ). While HDR can only occur in S/G2, NHEJ can happen in all cell cycle phases (except mitosis). How then is the repair choice made in S/G2 cells? Here we provide evidence demonstrating that APCCdh1 plays a critical role in choosing the repair pathways in S/G2 cells. Our results suggest that the default for all DSBs is to recruit 53BP1 and RIF1. BRCA1 is blocked from being recruited to broken ends because its recruitment signal, K63-linked poly-ubiquitin chains on histones, is actively destroyed by the deubiquitinating enzyme USP1. We show that the removal of USP1 depends on APCCdh1 and requires Chk1 activation known to be catalysed by ssDNA-RPA-ATR signalling at the ends designated for HDR, linking the status of end processing to RIF1 or BRCA1 recruitment.

PURPOSE:To identify Heptocellular carcinoma (HCC) associated antigens by proteomics, and validate whether autoantibodies against tumor-associated antigens (TAAs) could be used for diagnosis and conditional monitoring.RESULTS:The 78 kDa glucose regulated protein (GRP78) was selected as a candidate TAA. The titers of autoantibodies against 78 kDa glucose regulated protein (GRP78) from patients with HCC, liver cirrhosis (LC), and chronic hepatitis (CH) were significantly higher than that from normal controls (P<0.05, P<0.001, and P<0.01, respectively). The expression of autoantibodies against GRP78 was associated with clinical stage (P<0.01), portal vein invasion (P<0.05), and metastasis (P<0.05). The expression of anti-GRP78 antibodies was significantly higher 1 month after surgery in recurrent patients who had accepted hepatic resection 1 month after surgery compared to patients who had surgery before surgery or within 1 week after surgery (P<0.01 and P<0.001). Immunohistochemistry (IHC) showed higher expression of GRP78 in HCC compared to the non-HCC liver tissues (P <0.05).MATERIALS AND METHODS:HCC serum with high titer of autoantibodies against TAAs were screened and used for a proteome-based approach to identify HCC associated antigens. Indirect enzyme-linked immunoassay (ELISA) was used to detect the corresponding autoantibodies against TAAs.CONCLUSION:GRP78 is an autoantigen that could stimulate autoimmune responses and serve as a potential marker for recurrent and metastatic progression in HCC.