NEK2 contributes to radioresistance in esophageal squamous cell carcinoma by inducing protective autophagy via regulating TRIM21.

BACKGROUND: Radiotherapy (RT) has been identified as a vital treatment for esophageal squamous cell carcinoma (ESCC), while the development of radioresistance remains a major obstacle in ESCC management. The aim of this study was to investigate the effect of NIMA-related kinase 2 (NEK2) on radioresistance in ESCC cells and to reveal potential molecular mechanisms. METHODS: Human esophageal epithelial cells (HEEC) and human ESCC cell lines were obtained from the Research Center of the Fourth Hospital of Hebei Medical University (Shijiazhuang, China). Cell Counting Kit-8 (CCK-8) and flow cytometry assays were applied to assess the proliferation ability, cell cycle, apoptosis rates, and ROS production of ESCC cells. The colony-forming assay was used to estimate the effect of NEK2 on radiosensitivity. Autophagy was investigated by western blotting analysis, GFP-mRFP-LC3 fluorescence assay, and transmission electron microscopy (TEM). RESULTS: In the present study, our results showed that NEK2 was associated with radioresistance, cell cycle arrest, apoptosis, ROS production, and survival of ESCC. NEK2 knockdown could significantly inhibit growth while enhancing radiosensitivity and ROS production in ESCC cells. Interestingly, NEK2 knockdown inhibited ESCC cell autophagy and reduced autophagic flux, ultimately reversing NEK2-induced radioresistance. Mechanistically, NEK2 bound to and regulated the stability of tripartite motif-containing protein 21 (TRIM21). The accumulation of NEK2-induced light chain 3 beta 2 (LC3B II) can be reversed by the knockdown of TRIM21. CONCLUSION: These results demonstrated that NEK2 activated autophagy through TRIM21, which may provide a promising therapeutic strategy for elucidating NEK2-mediated radioresistance in ESCC.

Exploration of lymph node recurrence patterns and delineation guidelines of radiation field in middle thoracic oesophageal carcinomas after radical surgery: a real-world study.

BACKGROUND: Oesophageal squamous cell carcinoma is one of the most commonly diagnosed carcinomas in China, and postoperative radiotherapy plays an important role in improving the prognosis of patients. Carcinomas in different locations of the oesophagus could have different patterns of lymph node metastasis after surgery. METHODS: In this multicentric retrospective study, we enrolled patients with middle thoracic oesophageal squamous cell carcinomas from 3 cancer centres, and none of the patients underwent radiotherapy before or after surgery. We analysed the lymph node recurrence rates in different stations to explore the postoperative lymphatic recurrence pattern. RESULTS: From January 1st, 2014, to December 31st, 2019, 132 patients met the criteria, and were included in this study. The lymphatic recurrence rate was 62.1%. Pathological stage (P = 0.032) and lymphadenectomy method (P = 0.006) were significant predictive factors of lymph node recurrence. The recurrence rates in the supraclavicular, upper and lower paratracheal stations of lymph nodes were 32.6%, 28.8% and 16.7%, respectively, showing a high incidence. The recurrence rate of the subcarinal node station was 9.8%, while 8.3% (upper, middle and lower) thoracic para-oesophageal nodes had recurrences. CONCLUSIONS: We recommend including the supraclavicular, upper and lower paratracheal stations of lymph nodes in the postoperative radiation field in middle thoracic oesophageal carcinomas. Subcarinal station is also potentially high-risk, while whether to include thoracic para-oesophageal or abdominal nodes needs careful consideration.

Irradiation-induced exosomal HMGB1 to confer radioresistance via the PI3K/AKT/FOXO3A signaling pathway in ESCC.

BACKGROUND: Radioresistance is a major cause of treatment failure in esophageal squamous cell carcinoma (ESCC) radiotherapy, and the underlying mechanisms of radioresistance are still unclear. Irradiation (IR) stimulates changes in tumor-derived exosome contents, which can be taken up by recipient cells, playing an important role in the proliferation, cell cycle and apoptosis of recipient cells. This study investigated the effect of IR-induced exosomal high mobility group box 1 (HMGB1) on radioresistance in ESCC cells. METHODS: Plasma exosomes were isolated from 21 ESCC patients and 24 healthy volunteers, and the expression of HMGB1 was examined. Then, the therapeutic effect of radiotherapy was analyzed according to the different expression levels of plasma exosomal HMGB1 in ESCC patients. The uptake of exosomes by recipient cells was verified by immunofluorescence staining, and the localization of exosomes and HMGB1 in cells before and after IR was evaluated. The effects of IR-induced exosomes on cell proliferation, invasion, apoptosis, cell cycle distribution and radioresistance after HMGB1 knockdown were verified. Moreover, western blotting was used to measure changes in the expression of cyclin B1, CDK1, Bax, Bcl2, phosphorylated histone H2AX and the PI3K/AKT/FOXO3A pathway in the HMGB1-knockdown exosome group and the negative control group. RESULTS: The expression of HMGB1 in ESCC plasma exosomes was significantly increased compared with that in healthy volunteers, and high expression of HMGB1 in plasma exosomes was associated with radioresistance (P = 0.016). IR-induced the release of exosomal HMGB1 and promoted proliferation and radioresistance in recipient cells, with a sensitization enhancement ratio (SER) of 0.906 and 0.919, respectively. In addition, IR-induced exosomal HMGB1 promotes G2/M phase arrest by regulating the proteins cyclin B1 and CDK1, cooperating with the proteins Bax and Bcl2 to reduce the apoptosis rate through the PI3K/AKT/FOXO3A signaling pathway, and participated in IR-induced DNA damage repair through γH2AX. CONCLUSION: These findings indicate that high expression of plasma exosomal HMGB1 is associated with an adverse radiotherapy response. IR-induced exosomal HMGB1 enhances the radioresistance of ESCC cells.

Prognostic Significance of Prognostic Nutritional Index in Esophageal Squamous Cell Carcinoma Patients Undergoing Radical Radiotherapy: A Propensity Score Matching Analysis.

BACKGROUND: The preoperative prognostic nutritional index (PNI) is associated with postoperative complications and long-term survival of various cancers. However, its role in esophageal squamous cell carcinoma (ESCC) is inconclusive. The aim of this study was to identify the prognostic value of PNI in predicting survival in ESCC patients undergoing radical radiotherapy. METHODS: We retrospectively reviewed 354 ESCC patients undergoing radical radiotherapy. The time-dependent receiver operating characteristics was used to determine the optimal cutoff value. The association between PNI and survival was determined by Kaplan-Meier method and Cox regression model. Propensity score matching was applied to balance the baseline characteristics. RESULTS: PNI was positively correlated with hemoglobin (P < 0.001) and prealbumin (P < 0.001). The optimal cutoff value of PNI was set at 50.5. The 5-year overall survival (OS) in low PNI group and high PNI group were 20.8% and 34.0%, respectively (P < 0.001). The 5-year progression free survival in patients with low PNI and high PNI were 15.2% and 28.5%, respectively (P = 0.001). Multivariate analysis showed that PNI was a significant predictor for OS (P = 0.038). In the PSM analysis, PNI still remained an independent predictor for OS (P = 0.015). CONCLUSIONS: The PNI is a significant and independent predictor for OS of ESCC patients undergoing radical radiotherapy.

HMGB1 induces radioresistance through PI3K/AKT/ATM pathway in esophageal squamous cell carcinoma.

BACKGROUND: To explore the effect of HMGB1 on the radio-sensitivity of esophageal cancer cells through regulating the PI3K/Akt/ATM pathway. METHODS AND RESULTS: We observed the expression of HMGB1 and p-ATM in biopsies of esophageal cancer patients with immunohistochemical staining. Western blot and RT-qPCR were applied to detect the protein and RNA related to PI3K/Akt/ATM pathway, respectively. In addition, we inhibited the PI3K/Akt pathway with ly294002 and activated it with IGF1, then we explored the invasion, proliferation ability, and apoptosis of esophageal cancer cells in vitro by transwell, CCK8 assay, and flow cytometry respectively. In vivo, xenograft tumor model was established in nude mice to study the effect of HMGB1 on radioresistance via PI3K/AKT/ATM Signaling Pathway. The survival rate in patients with single positive/double negative expression of HMGB1 and p-ATM was significantly higher than in those with both positive expression of HMGB1 and p-ATM, the depletion of HMGB1 combined with ly294002 significantly inhibited cell proliferation and invasion ability, meanwhile, the addition of IGF1 reversed it. Meanwhile, depletion of HMGB1 and ly294002 promoted apoptosis and arrested the cancer cells in G0/G1 cell cycle with the decreased expression of Cyclin D1 and CDK4 and improved P16. We further validated these results in vivo, the application of HMGB1 silencing promoted apoptosis of xenograft tumors after radiation, especially combined with pathway inhibitor ly294002. CONCLUSIONS: Esophageal cancer patients with high expression of HMGB1 and p-ATM have a poor prognosis after chemo-radiotherapy. Down-regulation of HMGB1 may promote the radio-sensitivity of esophageal cancer cells through regulating PI3K/Akt/ATM pathway.

Clinical practice and outcome of radiotherapy for advanced esophageal squamous cell carcinoma between 2002 and 2018 in China: the multi-center 3JECROG Survey.

PURPOSE: To determine the survival and prognostic factors of esophageal squamous cell carcinoma (ESCC) patients undergoing radical (chemo)radiotherapy in the era of three-dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) in China. MATERIAL AND METHODS: The Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG) conducted the first nationwide survey of nine institutions. Detailed information was accumulated on 5185 patients with ESCC who received definitive 3DCRT/IMRT between 2002 and 2018. Relevant prognostic factors were evaluated to assess their influence on overall and progression-free survivals. RESULTS: After a median follow-up time of 47.0 (0.9-157.4) months, the 1-year, 2-year, 3-year and 5-year overall survival rates of the whole group were 69.8%, 46.6%, 37.9% and 30.1%. The 1-year, 2-year, 3-year, and 5-year progression-free survival rates were 54.1%, 36.6%, 30.5% and 24.9%. Multivariate analysis demonstrated that sex, clinical stage, treatment modality and radiation dose were prognostic factors for OS. The survival of patients who received concurrent chemoradiotherapy (CCRT) was better than that of patients who received radiotherapy alone or sequential chemoradiotherapy. Patients receiving adjuvant chemotherapy after CCRT had a better OS than patients receiving CCRT alone. Patients receiving higher radiation dose had a better OS than those patients receiving low-dose radiotherapy. CONCLUSIONS: The survival of ESCC patients undergoing radical (chemo)radiotherapy was relatively satisfactory in the era of 3DCRTand IMRT. As the largest-scale multicenter research on esophageal cancer radiotherapy conducted in China, this study establishes national benchmarks and helps to provide references for subsequent related researches.

Effect of SIB-IMRT-based selective dose escalation of local tumor on the prognosis of patients with esophageal cancer.

BACKGROUND: To investigate the effect of SIB-IMRT-based selective dose escalation to local tumor on the prognosis of patients with esophageal cancer (EC). METHODS: A total of 302 EC patients were enrolled. The prognostic factors of the entire group were initially analyzed, and the composition ratios of the two groups and the different doses of each fraction for PTV were compared. The propensity-score matching (PSM) was carried out (1:1 ratio), and the prognostic factors for the two groups were analyzed according to the results of COX. RESULTS: The median overall survival (OS) for all patients was 30.0 months (23.495-36.505 months), and the median disease-free survival (DFS) was 21.3 months (7.698-24.902 months). In multivariate analysis, chemotherapy, cTNM stage and dose-per-fraction for the PTV were independent prognostic factors for OS (P = 0.013, 0.000, 0.028) and DFS (P = 0.033, 0.000, 0.047). Multivariate analysis of patients after PSM revealed that cTNM staging and dose-per-fraction were the independent prognostic factors for OS (P = 0.000, 0.015). Chemotherapy, cTNM staging and dose-per-fraction for the PTV were the independent prognostic factors for DFS (P = 0.025, 0.010, 0.015). There was no significant difference in grade ≥ 2 acute toxicities between the two groups. A subgroup analysis of patients with a single dose of 2 Gy and > 2 Gy in the SIB-IMRT group showed that OS and DFS of the latter were significantly better than those of the former. CONCLUSION: The selective dose escalation to local tumors based on SIB-IMRT technique can improve the survival of patients received radical radiotherapy without increasing toxicities.

Knockdown of RNF2 enhances the radiosensitivity of squamous cell carcinoma in lung.

A previous study has reported that knockdown of RING finger protein 2 (RNF2) increases the radiosensitivity of esophageal cancer cells both in vitro and in vivo. However, the effect of RNF2 knockdown on radiosensitivity in squamous cell carcinoma (SqCC) remains unknown. For this, NCI-H226 and SK-MES-1 cells were exposed to X-ray irradiation and then RNF2 levels were determined. RNF2 was knocked-down and stable transfectants were selected. Radiosensitivity, cell proliferation, apoptosis, cell cycle, and γ-H2AX foci formation were evaluated. Interaction among ataxia telangiectasia mutated protein (ATM), mediator of DNA damage checkpoint 1 (MDC1), and H2AX were examined. Xenograft models were used to explore the effect of RNF2 knockdown on radiosensitivity in vivo. The results showed that RNF2 expression was significantly increased by X-ray irradiation. RNF2 knockdown combined with X-ray irradiation markedly inhibited cell proliferation, caused cell cycle arrest at the G1 phase, and induced cell apoptosis. In addition, RNF2 knockdown enhanced the radiosensitivity of SqCC cells, inhibited irradiation-induced γ-H2AX foci formation, and impaired the interactions among ATM, MDC1, and H2AX. Furthermore, combination of RNF2 knockdown and X-ray irradiation suppressed tumor growth and promoted tumor cell apoptosis in vivo. RNF2 may be a new therapeutic target to enhance the radiosensitivity of SqCC cells in lung.

Implication of clinical target delineation for T1b/T2 thoracic esophageal squamous cell carcinoma based on the pattern of lymph node metastases.

Aim: This study aimed to explore different patterns of lymph node metastases (LNM) in T1b and T2 thoracic esophageal squamous cell carcinoma (ESCC), and to further clarify its significance in radiotherapy target delineation. Materials & methods: Data of 1960 patients with T1b and T2 thoracic ESCC treated at different cancer centers were retrospectively analyzed. All patients underwent esophagectomy and lymphadenectomy. χ2 test and multivariate analysis were applied for analyzing clinicopathological factors related to LNM. Results: Age, location, tumor length, T stage and pathological grade were significantly associated with LNM (p < 0.01). For T1b ESCC, LNM rates in all sites were below 15%. For T2 upper thoracic ESCC, LNM rates were over 15% in upper mediastinal (15.8%). For T2 middle thoracic ESCC, LNM rates were middle mediastinal (17.2%) and abdominal (15.5%). For T2 lower thoracic ESCC, LNM rates were lower mediastinal (24.9%) and abdominal (22.5%). Subgroup analysis of T2 middle thoracic ESCC demonstrated that for patients older than 60 years, tumor length <4 cm and tumors were well differentiated. The LNM rates for abdominal were 11.9, 12.7 and 9.9%. Conclusion: Given the different patterns of LNM between T1b and T2 thoracic ESCC, target delineation should be adjusted accordingly.

Enteral nutrition in esophageal cancer patients treated with radiotherapy: a Chinese expert consensus 2018.

Esophageal cancer (EC) patients receiving radiotherapy are at a high risk of malnutrition, which can increase the side effects of radiotherapy, reduce the accuracy and sensitivity of radiotherapy and decrease treatment effect. Therefore, timely and correct nutritional treatment is crucial. To date, however, neither consensus nor guidelines on enteral nutrition (EN) specifically for EC patients receiving radiotherapy exist. Accordingly, an expert consensus conference was held to establish consensus on the use of EN in EC patients receiving radiotherapy. It reflected the opinions of a multidisciplinary group of experts and a review of the current literature, and established common guidelines for nutritional screening and assessment, nutrition counseling, indication for EN, access and formulas of EN, effect evaluation, nutrition plan adjustment, and home enteral nutrition.

Targeting protein for Xenopus kinesin-like protein 2 knockdown enhances radiation sensitivity of human lung squamous carcinoma cell.

The targeting protein for Xenopus kinesin-like protein 2 (TPX2) has been demonstrated to be associated with the tumourigenesis of many cancers. In the present study, we investigated the role and preliminary mechanism of TPX2 in the resistance of lung squamous carcinoma to radiation therapy. The results showed that SK-MES-1R and NCI-H226R cells were more resistant to X-ray irradiation than the parental cells (SK-MES-1 and NCI-H226). Moreover, TPX2 was upregulated in the radioresistant cells compared with the parental cells. TPX2 knockdown significantly decreased TPX2 expression in SK-MES-1 cells, while TPX2 overexpression increased TPX2 expression in NCI-H226 cells compared with the corresponding control cells. TPX2 knockdown enhanced the radiosensitivity of SK-MES-1 and promoted cell apoptosis following exposure to irradiation, whereas TPX2 overexpression decreased the radiosensitivity of NCI-H226 and inhibited cell apoptosis. In in vivo studies, the combination of TPX2 knockdown and irradiation significantly inhibited tumour growth, decreased tumour weight, downregulated TPX2 expression in tumour tissue and induced cell apoptosis in nude mice, while TPX2 overexpression exerted an opposite effect. Our results indicated that TPX2 was correlated with cell radioresistance and it might be served as a therapeutic target to enhance cell radiosensitivity in the radiation therapy of lung squamous carcinoma.

Analysis of the causes of failure after radical surgery in patients with PT3N0M0 thoracic esophageal squamous cell carcinoma and consideration of postoperative radiotherapy.

BACKGROUND: Five-year overall survival rate of TESCC after surgery is low (approximately 30% to 60%), so it is meaningful to discuss the significance of PORT. METHODS: We retrospectively collected the data of 227 patients with PT3N0M0 esophageal cancer (EC). The failure pattern after surgery was analyzed. Difference of adjuvant PORT in patients with PT3N0M0 TESCC and the appropriate population were explored based on the relevant studies. RESULTS: There were 58 cases with intrathoracic locoregional recurrence (LRR) after radical surgery and 27 cases with distant metastasis, including 10 cases of recurrence. The recurrence rate of mediastinal lymph nodes in the thoracic cavity was 50.0%. Univariate analysis revealed that compared with patients with middle and lower thoracic EC, the 3/5-year survival rate of patients with upper thoracic EC was significantly lower, accompanied with remarkably higher thoracic LRR. Compared with those with moderately- and well-differentiated TESCC, the 3/5-year survival rate of patients with poorly differentiated TESCC was significantly lower, whereas the distant metastasis rate was notably higher. Multivariate analysis revealed that different lesion locations and different pathologic differentiation were the independent prognostic factors. The lesion location and degree of differentiation were the independent influencing factors for thoracic LRR and distant metastasis, respectively. CONCLUSION: The intrathoracic LRR is the major failure pattern for patients with PT3N0M0 TESCC after conventional two-field lymphadenectomy. In addition, recurrence rate of PT3N0M0 TESCC was significantly higher in upper thoracic EC than in middle and lower thoracic EC. PORT is recommended to patients with PT3N0M0 upper TESCC.

A study of elderly patients with limited-stage small-cell lung cancer after combined chemoradiotherapy.

In this study, we evaluated the effect of chemotherapy (CT) and thoracic radiotherapy (RT) integration and the timing of RT on survival of elderly patients with limited-stage small-cell lung cancer. Eighty patients were retrospectively analyzed. All the patients revived thoracic RT and 70 patients received ≥2 cycles of CT. Twenty-two patients received RT sequentially to CT, 19 with RT consolidated with CT, and 29 with RT concurrent with CT. Early chest irradiation was defined as beginning RT after 1-3 cycles of CT (n = 44), and late chest irradiation was defined as occurring after ≥4 cycles of CT (n = 26). Twenty-six patients (32.5%) achieved complete response, 37 (46.2%) partial response, 10 (12.5%) stable disease, and 7 (8.7%) progressive disease. The median survival time for all patients was 19 months. The 1-, 2-, and 3-year overall survival (OS) rates were 68.9%, 41.3%, and 31.7%, respectively. In univariate analyses, the volume of the primary tumor, CT, treatment modality, timing of RT, target volume, and RT dose were significantly associated with OS. At 3 years, concomitant chemoradiotherapy was superior to consolidated and sequential chemoradiotherapy (40.0% vs. 36.9% vs. 40.0%, respectively). The rate of OS at 3 years was 37.1% for patients receiving early-RT and 27.8% for those receiving late-RT (P = 0.006). Multivariate analysis showed that CT and RT dose were independent factors influencing OS. Concurrent chemoradiotherapy resulted in a high survival rate. A radiation dose-response relationship was observed, and a dose of at least 60-Gy daily radiation demonstrated improved survival.

[Low dose volume histogram analysis of the lungs in prediction of acute radiation pneumonitis in patients with esophageal cancer treated with three-dimensional conformal radiotherapy].

OBJECTIVE: To investigate the predictive value of low dose volume of the lung on acute radiation pneumonitis (RP) in patients with esophageal cancer treated with three-dimensional conformal radiotherapy (3D-CRT) only, and to analyze the relation of comprehensive parameters of the dose-volume V5, V20 and mean lung dose (MLD) with acute RP. METHODS: Two hundred and twenty-two patients with esophageal cancer treated by 3D-CRT have been followed up. The V5-V30 and MLD were calculated from the dose-volume histogram system. The clinical factors and treatment parameters were collected and analyzed. The acute RP was evaluated according to the RTOG toxicity criteria. RESULTS: The acute RP of grade 1, 2, 3 and 4 were observed in 68 (30.6%), 40 (18.0%), 8 (3.6%) and 1 (0.5%) cases, respectively. The univariate analysis of measurement data:The primary tumor length, radiation fields, MLD and lung V5-V30 had a significant relationship with the acute RP. The magnitude of the number of radiation fields, the volume of GTV, MLD and Lung V5-V30 had a significant difference in whether the ≥ grade 1 and ≥ grade 2 acute RP developed or not. Binary logistic regression analysis showed that MLD, Lung V5, V20 and V25 were independent risk factors of ≥ grade 1 acute RP, and the radiation fields, MLD and Lung V5 were independent risk factors of ≥ grade 2 acute RP. The ≥ grade 1 and ≥ grade 2 acute RP were significantly decreased when MLD less than 14 Gy, V5 and V20 were less than 60% and 28%,respectively. When the V20 ≤ 28%, the acute RP was significantly decreased in V5 ≤ 60% group. When the MLD was ≤ 14 Gy, the ≥ 1 grade acute RP was significantly decreased in the V5 ≤ 60% group. When the MLD was >14 Gy, the ≥ grade 2 acute RP was significantly decreased in the V5 ≤ 60% group. CONCLUSIONS: The low dose volume of the lung is effective in predicting radiation pneumonitis in patients with esophageal cancer treated with 3D-CRT only. The comprehensive parameters combined with V5, V20 and MLD may increase the effect in predicting radiation pneumonitis.

A novel DNA damage repair gene-related prognostic model for evaluating the prognosis and tumor microenvironment infiltration of esophageal squamous cell carcinoma.

BACKGROUND: This study aimed to investigate the potential prognostic value of DNA damage repair genes (DDRGs) in esophageal squamous cell carcinoma (ESCC) and their relationship with immune-related characteristics. METHODS: We analyzed DDRGs of the Gene Expression Omnibus database (GSE53625). Subsequently, the GSE53625 cohort was used to construct a prognostic model based on least absolute shrinkage and selection operator regression, and Cox regression analysis was used to construct a nomogram. The immunological analysis algorithms explored the differences between the potential mechanism, tumor immune activity, and immunosuppressive genes in the high- and low-risk groups. Of the prognosis model-related DDRGs, we selected PPP2R2A for further investigation. Functional experiments were conducted to evaluate the effect on ESCC cells in vitro. RESULTS: A 5-DDRG (ERCC5, POLK, PPP2R2A, TNP1 and ZNF350) prediction signature was established for ESCC, stratifying patients into two risk groups. Multivariate Cox regression analysis showed that the 5-DDRG signature was an independent predictor of overall survival. Immune cells such as CD4 T cells and monocytes displayed lower infiltration levels in the high-risk group. Additionally, the immune, ESTIMATE, and stromal scores in the high-risk group were all considerably higher than those in the low-risk group. Functionally, knockdown of PPP2R2A significantly suppressed cell proliferation, migration and invasion in two ESCC cell lines (ECA109 and TE1). CONCLUSION: The clustered subtypes and prognostic model of DDRGs could effectively predict the prognosis and immune activity of ESCC patients.

YTHDF3 mediates HNF1α regulation of cervical cancer radio-resistance by promoting RAD51D translation in an m6A-dependent manner.

Radiotherapy, as an important primary treatment, has effectively improved the survival of patients with cervical cancer (CC). Some patients, however, do not benefit optimally from radiotherapy because of radio-resistance. Therefore, identifying radio-resistance biomarkers and unravelling the underlying mechanisms is of critical importance for these patients. In the present study, we found significant upregulation of hepatocyte nuclear factor 1-alpha (HNF1α) expression in radio-resistant cervical cancer tissues and cell lines. Depletion of HNF1α reduced and overexpression of HNF1α promoted the resistance of CC cells to irradiation in vitro and in vivo. HNF1α positively regulated DNA repair protein RAD51 homologue 4 (RAD51D) at the protein level but not at the mRNA level. Mechanistically, upregulation of HNF1α enhanced YTH domain-containing family protein 3 (YTHDF3) transcription, which in turn promoted RAD51D mRNA N6 -methyladenosine (m6A) modification. YTHDF3 mediates HNF1α regulation of cervical cancer radio-resistance by promoting RAD51D translation in an m6A-dependent manner. The HFN1α/YTHDF3/RAD51D regulatory axis was found to play a critical role in conferring radio-resistance of CC cells. In conclusion, dysregulation of the HFN1α/YTHDF3/RAD51D axis may promote the radio-resistance of CC cells. Blocking this pathway may provide therapeutic benefits against CC radio-resistance.

NEK2 promotes esophageal squamous cell carcinoma cell proliferation, migration and invasion through the Wnt/ß-catenin signaling pathway.

OBJECTIVES: The NEK2 (never in mitosis gene A-related kinase 2), a serine/threonine kinase involved in chromosome instability and tumorigenesis. Hence, this study aimed to explore the molecular function of NEK2 in esophageal squamous cell carcinoma (ESCC). METHODS: By available transcriptome datasets (GSE53625 cohort, GSE38129 cohort, and GSE21293 cohort), we analyzed the differentially expressed genes in invading and non-invading ESCC. Subsequently, we evaluated the association between NEK2 expression level and clinical outcomes through Kaplan-Meier analysis method. The quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB) analyses were performed to determine the expression levels of NEK2 mRNA and protein, respectively. We knocked down the NEK2 expression in ESCC cells (ECA109 and TE1), and evaluated the NEK2 biology function associated with ESCC cell proliferation, migration, invasion, and colony formation abilities. Finally, the downstream pathway of NEK2 was analyzed through Gene Set Enrichment Analysis (GSEA) and validated the regulatory mechanism of NEK2 on the potential pathway through WB. RESULTS: We found that NEK2 was highly expressed in ESCC cells compared with human esophageal epithelial cells (HEEC) (P < 0.0001), and high NEK2 expression was remarkably associated with poor survival (P = 0.019). Knockdown of NEK2 showed the significant inhibitory effect for tumorigenesis, and suppressed the ESCC cells proliferation, migration, invasion, and formation of colonies abilities. Additionally, GSEA revealed that Wnt/ß-catenin pathway was a downstream pathway of NEK2. WB results further validated the regulatory mechanism of NEK2 for Wnt/ß-catenin signaling. CONCLUSIONS: Our results indicated that NEK2 promotes ESCC cell proliferation, migration and invasion by activating the Wnt/ß-catenin pathway. NEK2 could be a promising target for ESCC.

Immune checkpoint inhibitors combined with or without radio(chemo)therapy for locally advanced or recurrent/metastatic esophageal squamous cell carcinoma.

OBJECTIVE: This study was designed to investigate the efficacy and prognostic factors for immune checkpoint inhibitors (ICIs) combined with or without radio(chemo)therapy and to evaluate their toxicity in patients with locally advanced or recurrent/metastatic esophageal squamous cell carcinoma (LA/RM ESCC). METHODS: In this study, 198 patients with locally advanced or recurrent/metastatic (LA/RM) ESCC who received ICIs combined with or without radiotherapy/chemotherapy in the Department of Radiotherapy of the Fourth Hospital of Hebei Medical University were retrospectively analyzed. Univariate and multivariate analyses were performed to determine the prognostic factors for overall survival (OS) and progression free survival (PFS). The factors affecting treatment response and the occurrences of treatment-related adverse events (trAEs) were analyzed. RESULTS: The median OS and PFS were 30.4 months (95% confidence interval [CI] 15.1-45.7 months) and 15.3 months (95% CI 12.8-17.8 months), respectively. Univariate and multivariate analysis showed that the number of ICI cycles, the intervention of radiotherapy and dysphagia were independent factors affecting OS (Hazard ratio [HR] = 0.39, 2.043 and 0.365, respectively; P = 0.018, 0.001 and 0.032, respectively). The intervention of radiotherapy was an independent factor for PFS (hazard ratio [HR] = 18.149, P = 0.013). The median OS and PFS for patients who had complete response and partial response (Objective response, ORR) were 50.8 months (95% CI 25.8-75.7 months) and 20.5 months (95% CI 14.1-27.0), respectively, which were significantly higher than those in the non-ORR group (OSnon-ORR:17.5 months, 95% CI 14.0-21.0; χ2 = 13.881, P < 0.001; PFSnon-ORR: 12.1 months, 95% CI 10.1-14.1, χ2 = 10.676, P = 0.001). The intervention of radiotherapy could improve treatment response (χ2 = 47.725, P = 0.000). In entire study population, 83 patients (41.9%) had ≥ grade 2 trAEs. CONCLUSIONS: ICIs combined with radiotherapy/chemotherapy are safe and effective in LA/RM ESCC patients. Intervention of radiotherapy, the number of immunotherapy cycles and occurrence of dysphagia affecting the overall survival of LR/RM ESCC patients. Intervention of radiotherapy was an independent prognosis factor for OS and PFS and associated with better treatment response.

High-Dose Versus Standard-Dose Intensity-Modulated Radiotherapy With Concurrent Paclitaxel Plus Carboplatin for Patients With Thoracic Esophageal Squamous Cell Carcinoma: A Randomized, Multicenter, Open-Label, Phase 3 Superiority Trial.

PURPOSE: The standard dose (SD) of definitive concurrent chemoradiotherapy (dCRT) remains 50.4 Gy in patients with esophageal cancer; a higher dose, when applied with conventional radiation therapy techniques, increases toxicities without improving survival. We investigated whether a high dose of 59.4 Gy using intensity-modulated radiation therapy (IMRT) would improve survival without increasing toxicities. METHODS: Patients with inoperable thoracic esophageal squamous cell carcinoma (SCC) referred for dCRT were randomly assigned (1:1) to high-dose (HD) IMRT (59.4 Gy) or SD IMRT (50.4 Gy). Chemotherapy consisted of 6 cycles of concurrent weekly paclitaxel and carboplatin and a maximum of 2 cycles of consolidation chemotherapy. Nutritional intervention was implemented for patients with malnutrition on the basis of nutritional screening. The primary endpoint was median overall survival (mOS). Analyses were by modified intention to treat. RESULTS: Between April 30, 2016, and April 30, 2019, 167 patients were enrolled at 9 participating centers in China. Seventy-one patients in the HD and 73 patients in the SD groups were included in the analysis; 86.8% of the patients completed radiation therapy and 70.1% received 5 or 6 cycles of concurrent chemotherapy. The median follow-up was 36.0 months. The mOS was 28.1 and 26.0 months in the HD and SD arms, respectively (P = .54). A total of 7 treatment-related deaths were observed. Grade 3 or worse treatment-related toxicities were observed in 62% and 68.5% of the patients in the HD and SD arms, respectively (P = .675). CONCLUSIONS: For patients with inoperable thoracic esophageal SCC, a dose of 59.4 Gy did not improve survival compared with the SD of dCRT using IMRT.

Prognostic analysis of limited-stage small cell lung cancer after chemoradiotherapy.

BACKGROUND: Chemotherapy (CT) in combination with thoracic radiotherapy (RT) can improve the survival of patients with limited-stage small cell lung cancer (LSSCLC). In the current study, we evaluated the prognostic factors, especially the effect of the therapy integration and the timing of RT, on survival. PATIENTS AND METHODS: We retrospectively studied 142 patients with LS-SCLC. All patients received thoracic RT and 126 patients received at least 2 cycles of CT; 38 patients received RT following CT cycles, 32 received RT between CT cycles, and 56 received RT concurrently with CT. RESULTS: For all patients, the 1-, 3-, and 4-year overall survival (OS) rates were 68.3, 31.2, and 28.6%, respectively. In univariate analyses, the volume of the primary tumor, T classification, CT, the target volume, the RT dose, and the treatment response were significantly associated with OS. The multivariate analysis showed that CT, the timing of RT, and RT dose were independent factors influencing the OS. CONCLUSION: Concurrent chemoradiotherapy could result in high survival rates, and early integration of thoracic RT was associated with a better outcome. A radiation dose-response relationship was observed in our study.