Survival Of Esophageal Squamous Cell Carcinoma Patients Research Articles

NUAK1 promotes tumor metastasis through upregulating slug transcription in esophageal squamous cell carcinoma

BackgroundMetastasis is still a major cause of poor pathological outcome and prognosis in esophageal squamous cell carcinoma (ESCC) patients. NUAK1 has been reported highly expressed in many human cancers and is associated with the poor prognosis of cancer patients. However, the role of NUAK1 and its underlying signaling mechanism in ESCC metastasis remain unclear.MethodsExpression of NUAK1 in ESCC was detected by real-time quantitative RT-PCR (qRT-PCR), Western blotting and immunohistochemical staining. MTT, colony formation, wound-healing and transwell assays were used to determine the role NUAK1 in vitro. Metastasis was evaluated by use of an experimental pulmonary metastasis model in BALB/c-nu/nu mice. The mechanisms were assessed by using coimmunoprecipitation, immunofluorescence and dual-luciferase reporter gene experiments.ResultsNUAK1 was highly expressed in ESCC tissues compared with the adjacent normal esophageal epithelial tissues. Moreover, the elevated expression of NUAK1 positively correlated with tumor invasion depth, lymph node metastasis, pathological TNM stage, and poor survival in ESCC patients. Further experiments showed that NUAK1 overexpression did not change the cell viability and colony formation of ESCC cells, while remarkably promoted the migration and invasion in vitro and experimental pulmonary metastasis in vivo. Mechanistically, NUAK1 enhanced the transcription level of Slug, which enhanced the migratory and invasive capability of ESCC cells. Consistently, silencing Slug almost completely diminished the migration and invasion of NUAK1-overexpressing ESCC cells. Further studies demonstrated that NUAK1 upregulated the transcription activity of Slug through activating the JNK/c-Jun pathway.ConclusionThese results demonstrated that NUAK1 promoted the metastasis of ESCC cells through activating JNK/c-Jun/Slug signaling, indicating NUAK1 is a promising therapeutic target for metastatic ESCC.

Clinical Significance of Porphyromonas gingivalis Enriching Cancer Stem Cells by Inhibiting Programmed Cell Death Factor 4 in Esophageal Squamous Cell Carcinoma.

Studies have confirmed that the colonization of Porphyromonas gingivalis (Pg) could promote the malignant evolution of esophageal squamous cell carcinoma (ESCC). Since pathogenic microorganisms can promote malignant tumor proliferation by inhibiting programmed cell death factor 4 (PDCD4) and the decrease of PDCD4 activity can enhance the stemness of cancer cells, we here investigated the functional mechanism by which Pg promoted ESCC chemoresistance and malignancy through inhibiting PDCD4 and enriching cancer stem cells (CSCs). The effects of Pg and PDCD4 on CSCs, chemoresistance and malignancy of ESCC cells were evaluated by in vitro studies. The expression of Pg, PDCD4, and ALDH1 in ESCC tissues were detected by IHC, and the correlations between each index and postoperative survival of ESCC patients were analyzed. The results showed that Pg could inhibit PDCD4 expression and lead to CSCs enrichment in ESCC cells. After eliminating Pg, the expression of PDCD4 was upregulated, the percentage of CSCs, chemoresistance and malignancy were decreased. ESCC patients with Pg-positive, PDCD4-negative, and ALDH1-positive have a significant shorter survival. This study proved that eliminating Pg and blocking CSCs enrichment caused by decreasing PDCD4 activity may provide a new strategy for ESCC treatment.

Identification and validation of a prognostic signature of cuproptosis-related genes for esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a highly lethal form of cancer. Cuproptosis is a recently discovered form of regulated cell death. However, its significance in ESCC remains largely unknown. In this study, we observed significant expression differences in most of the 12 cuproptosis-related genes (CRGs) in the TCGA-ESCC dataset, which was validated using GSE20347, GSE38129, and individual ESCC datasets. We were able to divide patients in the TCGA-ESCC cohort into two subgroups based on disease, and found significant differences in survivor outcomes and biological functions between these subgroups. Additionally, we identified 11 prognosis-related genes from the 12 CRGs using LASSO COX regression analysis and constructed a CRGs signature for ESCC. Patients were categorized into high- and low-risk subgroups based on their median risk score, with those in the high-risk subgroup having significantly worse overall survival than those in the low-risk subgroup. The CRGs signature was also highly accurate in predicting prognosis and survival outcomes. Univariate and multivariate Cox regression analyses revealed that 8 of the 11 CRGs were independent prognostic factors for predicting survival in ESCC patients. Furthermore, our nomogram performed well and could serve as a useful tool for predicting prognosis. Finally, our risk model was found to be relevant to the sensitivity of targeted agents and immune infiltration. Functional enrichment analysis demonstrated that the risk model was associated with biological pathways of tumor migration and invasion. In summary, our study may provide a promising prognostic signature based on CRGs and offers potential targets for personalized therapy.

205. LONGITUDINAL PATIENT-REPORTED OUTCOMES AFTER MINIMALLY INVASIVE MCKEOWN ESOPHAGECTOMY IN PATIENTS WITH ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background Surgery for esophageal squamous cell carcinoma (ESCC) is characterized by a poor prognosis and high complication rate, resulting in a heavy symptom burden and poor quality of life (QOL). Neoadjuvant therapy followed by surgery improved the postoperative survival of ESCC patients. This study was a longitudinal patient-reported outcomes (PROs) evaluation to compare the effects of neoadjuvant therapy followed by minimally invasive Mckeown esophagectomy and surgery without neoadjuvant therapy from the patient’s perspective. Methods We investigated ESCC patients who underwent minimally invasive Mckeown esophagectomy in a single centre. Longitudinal data on clinical characteristics and PROs were collected. The MD Anderson Symptom Inventory and the European Organization for Research and Treatment of Cancer (EORTC)‘s quality of life questionnaires were used to assess symptoms and QOL before and after surgery. Compared the PROs’ trajectories during the investigation. Results Overall, 244 eligible ESCC patients were enrolled, of which 78 (group A) underwent neoadjuvant therapy followed by surgery, and 166 (group B) underwent surgery without neoadjuvant therapy. On postoperative day 5, dry mouth (p = 0.035) was more evident in group A. In postoperative month 1, patients in group A reported more disturbed sleep (p = 0.012) and drowsy (p = 0.050). In the sixth month, patients in group A had more symptom burden of disturbed sleep (p = 0.038), distress (p = 0.005) and lack of appetite (p = 0.049), and had worse physical (p = 0.050), role (p = 0.003) and emotional (p = 0.020) functions. Twelve months after surgery, group A had a worse social function (p = 0.019). Conclusion The longitudinal changes in postoperative symptoms and QOL were about the same in both groups. But at some point, especially in the sixth month after surgery, patients who underwent neoadjuvant therapy followed by surgery had a heavier symptom burden and a poorer QOL.

Unveiling the prognostic significance of SOX5 in esophageal squamous cell carcinoma: a comprehensive bioinformatic and experimental analysis.

This study aimed to investigate the expression and prognostic significance of SOX5 in esophageal squamous cell carcinoma (ESCC). Gene Expression Omnibus (GEO) data were analyzed to assess SOX5 expression in ESCC and normal tissues. Survival analysis was performed to evaluate its prognostic significance. Pathway enrichment analysis was conducted to identify pathways associated with low SOX5 expression. Methylation status of CpG sites in ESCC cases was examined, and SOX5 expression was evaluated. Differential expression and ChIP-seq data analyses were used to identify genes significantly correlated with SOX5 and to obtain target genes. A protein-protein interaction (PPI) network was constructed using hub genes, and their association with immune cell infiltration was determined. In vitro ESCC cell experiments validated the findings. SOX5 was significantly downregulated in ESCC samples compared to normal samples. Its downregulation was associated with shorter survival in ESCC patients. Pathway enrichment analysis revealed enrichment in regulated necrosis, NLRP3 inflammasome, formation of the cornified envelope, and PD-1 signaling. Methylation status of two CpG sites negatively correlated with SOX5 expression. Differential expression analysis identified 122 genes significantly correlated with SOX5, and 28 target genes were obtained from ChIP-seq analysis. Target genes were enriched in DNA replication, cell cycle, spindle, and ATPase activity. Five hub genes were identified, and the PPI network showed significant associations with immune cell infiltration. In vitro experiments confirmed SOX5 downregulation, upregulation of hub genes, and their functional effects on ESCC cell apoptosis and proliferation. These findings enhance understanding of SOX5 in ESCC and potential therapeutic strategies.

Predicting role of circulating tumor DNA and blood-based tumor mutational burden in esophageal squamous cell carcinoma receiving chemoradiotherapy combined with toripalimab: Exploratory analyses from a phase II trial (EC-CRT-001).

4056 Background: EC-CRT-001 is a phase II trial investigating the efficacy of toripalimab (an anti-PD1 antibody) combined with definitive chemoradiotherapy (CRT) in locally advanced esophageal squamous cell carcinoma (ESCC) and the results demonstrated encouraging antitumor activity and acceptable toxicity. This exploratory analysis was performed to evaluate the role of circulating tumor DNA (ctDNA) and blood-based tumor mutational burden (bTMB) for efficacy prediction. Methods: Forty-two patients from the phase II trial (NCT04005170) who received toripalimab (240 mg every 3 weeks for up to 1 year, or disease progression, or unacceptable toxicity) combined with definitive CRT (irradiation with 50.4 Gy in 28 fractions concurrent with 5 cycles of weekly paclitaxel in 50 mg/m2 and cisplatin in 25 mg/m2) were enrolled. Plasma samples were collected before, during, and after CRT. Targeted next-generation sequencing was performed on a total of 118 plasma samples and 35 matched tumor samples using a panel covering 474 cancer-associated genes. Results: Twenty-six (62%) of 42 patients achieved clinical complete response (cCR) at three months after CRT. ctDNA was detected in 29 (72.5%) of 40 patients at baseline. The positive rate of ctDNA decreased to 43.9% (20/41) during CRT and continued to descend to 27.0% (10/37) at the completion of CRT. A higher cCR rate was observed in patients with negative during-CRT ctDNA compared to those with detectable ctDNA (82.6% vs. 38.9%, P = 0.008). Patients with post-CRT detectable ctDNA also had poorer cCR rate (30.0% vs. 77.8%, P = 0.017). Within a median follow-up of 24.0 months (IQR 13.7-27.9), the median progression-free survival (PFS) was 12.2 months (95%CI: 8.4-16.0) and median overall survival (OS) was not reached for the whole cohort. Patients with during-CRT detectable ctDNA had shorter PFS compared to ctDNA-negative patients (HR = 2.57, 95%CI: 1.18-5.60, P = 0.014). Similarly, patients with post-CRT detectable ctDNA also had a significantly increased risk of disease progression (HR = 2.88, 95%CI: 1.21-6.83, P = 0.012) and death (HR = 3.67, 95%CI: 1.41-9.55, P = 0.004). Moreover, patients with higher bTMB ( > 1) detected during CRT were associated with a favorable OS (HR = 0.33, 95%CI: 0.13-0.88, P = 0.027). Improved PFS was also observed in those patients with higher post-CRT bTMB ( > 3) (HR = 0.28, 95%CI: 0.08-0.96, P = 0.042). Conclusions: Negative ctDNA status and higher bTMB during or after CRT were associated with better tumor response and favorable survival in ESCC patients who underwent definitive CRT combined with toripalimab. Dynamic ctDNA has great potential in predicting efficacy and risk of disease progression in ESCC. Clinical trial information: NCT04005170 .

Identification and Prognostic Effect of Extramural Venous Invasion in Locally Advanced Esophageal Squamous Cell Carcinoma.

The role of extramural venous invasion (EMVI) in esophageal cancer is still unclear. This study aimed to identify EMVI and assess its impact on survival and recurrences in esophageal squamous cell carcinoma (ESCC). Retrospectively, we reviewed resection specimens of 147 locally advanced ESCC (pT3-T4aN0-3M0) patients who had a curative intended surgery alone at the Cancer Hospital of Shantou University from March 2009 to December 2013. After confirming pT≥3 in hematoxylin-eosin tumor slides, EMVI was evaluated by Verhoeff and Caldesmon staining. The impact of EMVI with other clinicopathological characteristics and survival were analyzed using the χ 2 test, Cox regression, and Kaplan-Meier method. EMVI was present in 30.6% (45/147) of the P ≥T3 ESCCs and associated with lymph-vascular invasion and poor differentiation grade ( P <0.05). Disease-free survival and overall survival in patients with EMVI-absent tumors were about 2.0 times longer than in those with EMVI-present tumors. In pN0 patients, EMVI-presence was associated with poor overall survival (HR 4.829, 95% CI 1.434-16.26, P =0.003) and Disease-free Survival (HR 4.026, 95% CI 0.685-23.32, P =0.018). In pN1-3 patients, EMVI had no additional effect on survival. Conclusions EMVI has an independent adverse prognostic effect on survival in ESCC patients after surgery alone. EMVI should be included in pathology reports as it might contribute to identify high-risk patients for potential additional treatment.

RNF106 aggravates esophageal squamous cell carcinoma progression through LATS2/YAP axis

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal solid tumors in China, with the 5-year overall survival rate less than 20%. Although the carcinogenic process of ESCC is still not clear, recent studies using whole genomic profiling revealed that dysregulation of Hippo signaling pathway might play important roles in ESCC progression. The ubiquitin-like with PHD and RING finger domain 1 (RNF106) was a modifier of DNA methylation and histone ubiquitination. In this study, we evaluate the oncogenic function of RNF106 in ESCC both in vitro and in vivo. Wound healing and transwell data showed that RNF106 was required for ESCC cell migration and invasion. RNF106 depletion dramatically restrained Hippo signaling targeted gene expression. The bioinformatics analysis displayed that RNF106 was increased in ESCC tumor tissues and related with poor survival in ESCC patients. Mechanistic studies demonstrated that RNF106 was associated with LATS2 and facilitate LATS2 K48-linked ubiquitination and degradation, which subsequently inhibited YAP phosphorylation and promoted YAP oncogenic function in ESCC. Taken together, our study revealed a novel link between RNF106 and Hippo signaling in ESCC, suggesting that RNF106 could be a promising target for ESCC therapy.

Intratumoral microbiome impacts immune infiltrates in tumor microenvironment and predicts prognosis in esophageal squamous cell carcinoma patients.

Different intratumoral microbiotaexist in different tumors and play a crucial function in carcinogenesis. However, whether they impact clinical outcomes in esophageal squamous cell carcinoma (ESCC) and their mechanism remain unclear. 16S rDNA amplicon sequencing was performed on surgically resected samples from 98 ESCC patients to analyze intratumoral microbiome abundance and composition. Multiplex fluorescent immunohistochemistry staining was used to profile the phenotypes of immune infiltrates in the tumor microenvironment (TME). Patients with higher intratumoral Shannon index had significantly worse surgical outcomes. When patients were divided into short-term survivors and long-term survivors based on the median survival time, both intratumoral alpha-diversity and beta-diversity were found to be significantly inconsistent, and the relative abundance of Lactobacillus and Leptotrichia emerged as the two microorganisms that probably influenced the survival of ESCC patients. Only Lactobacillus in ESCC was validated to significantly worsen patients' prognoses and to be positively correlated with the Shannon index. Multivariate analysis revealed that the intratumoral Shannon index, the relative abundance of Lactobacillus, and the pathologic tumor-node-metastasis (pTNM) stage were independently associated with patients' overall survival. Furthermore, the relative abundance of both Lactobacillus and Shannon index was positively correlated with the proportions of PD-L1+ epithelial cells (ECs) and tumor-associated macrophages (TAMs). The Shannon index was negatively correlated with the proportions of natural killer (NK) cells in the TME. A high abundance of intratumoral Lactobacillus and bacterial alpha-diversity was associated with the formation of the immunosuppressive TME and predicted poor long-term survival in ESCC patients.

High FN1 expression is associated with poor survival in esophageal squamous cell carcinoma.

Esophageal cancer (EC) is a serious threat to human health. The expression of fibronectin 1 (FN1) in esophageal squamous cell carcinoma (ESCC) remains controversial. The purpose of this study was to elucidate the expression of FN1 in ESCC and to assess the value of FN1 in the prognosis of ESCC patients. 100 ESCC patients from January 2015 to March 2016 were recruited in this study. qRT-PCR and immunohistochemistry (IHC) were used to detect FN1 mRNA and protein expression. The correlation between FN1 expression levels and prognosis of ESCC patients was analyzed. The qRT-PCR results showed that the expression of FN1 mRNA was significantly higher in ESCC tumor tissues than in adjacent esophageal tissues (P < .01). IHC results showed that FN1 protein was expressed in both tumor cells and stroma. High expression of FN1 mRNA and FN1 protein in ESCC tumor tissues was significantly correlated with the depth of tumor invasion, lymph node metastasis and clinical stage of the tumor (P < .05). Survival analysis revealed that patients with higher FN1 mRNA and protein expression had significantly lower survival rates than those with lower FN1 mRNA or protein expression (P < .01). Multivariate cox regression analysis showed that high FN1 protein expression in ESCC tumor tissues was an independent risk factor for low survival in ESCC patients (P < .05). High expression of FN1 protein in ESCC tumor tissue is an independent poor prognostic factor. FN1 protein could be a potential target for the treatment of ESCC.

Porphyromonas gingivalis promotes malignancy and chemo-resistance via GSK3β-mediated mitochondrial oxidative phosphorylation in human esophageal squamous cell carcinoma

Our prior studies have confirmed that long-term colonization of Porphyromonas gingivalis (Pg) and overexpression of the inflammatory factor glycogen synthase kinase 3β (GSK3β) promote the malignant evolution of esophageal squamous cell carcinoma (ESCC). We aimed to investigate the functional mechanism by which Pg could promote ESCC malignancy and chemo-resistance through GSK3β-mediated mitochondrial oxidative phosphorylation (mtOXPHOS), and the clinical implications. The effects of Pg and GSK3β on mtOXPHOS, malignant behaviors and response to paclitaxel and cisplatin treatment of ESCC cells were evaluated by in vitro and in vivo studies. The results showed that Pg induced high expression of the GSK3β protein in ESCC cells and promoted the progression and chemo-resistance via GSK3β-mediated mtOXPHOS in human ESCC. Then, Pg infection and the expression of GSK3β, SIRT1 and MRPS5 in ESCC tissues were detected, and the correlations between each index and postoperative survival of ESCC patients were analysed. The results showed that Pg-positive ESCC patients with high-expression of GSK3β, SIRT1 and MRPS5 have significant short postoperative survival. In conclusion, we demonstrated that the effective removal of Pg and inhibition of its promotion of GSK3β-mediated mtOXPHOS may provide a new strategy for ESCC treatment and new insights into the aetiology of ESCC.

Long-term effect of hospital volume on the postoperative prognosis of 158,618 patients with esophageal squamous cell carcinoma in China.

The impact of hospital volume on the long-term survival of esophageal squamous cell carcinoma (ESCC) has not been well assessed in China, especially for stage I-III stage ESCC. We performed a large sample size study to assess the relationships between hospital volume and the effectiveness of ESCC treatment and the hospital volume value at the lowest risk of all-cause mortality after esophagectomy in China. To investigate the prognostic value of hospital volume for assessing postoperative long-term survival of ESCC patients in China. The date of 158,618 patients with ESCC were collected from a database (1973-2020) established by the State Key Laboratory for Esophageal Cancer Prevention and Treatment, the database includes 500,000 patients with detailed clinical information of pathological diagnosis and staging, treatment approaches and survival follow-up for esophageal and gastric cardia cancers. Intergroup comparisons of patient and treatment characteristics were conducted with the X2 test and analysis of variance. The Kaplan-Meier method with the log-rank test was used to draw the survival curves for the variables tested. A Multivariate Cox proportional hazards regression model was used to analyze the independent prognostic factors for overall survival. The relationship between hospital volume and all-cause mortality was assessed using restricted cubic splines from Cox proportional hazards models. The primary outcome was all-cause mortality. In both 1973-1996 and 1997-2020, patients with stage I-III stage ESCC who underwent surgery in high volume hospitals had better survival than those who underwent surgery in low volume hospitals (both P<0.05). And high volume hospital was an independent factor for better prognosis in ESCC patients. The relationship between hospital volume and the risk of all-cause mortality was half-U-shaped, but overall, hospital volume was a protective factor for esophageal cancer patients after surgery (HR<1). The concentration of hospital volume associated with the lowest risk of all-cause mortality was 1027 cases/year in the overall enrolled patients. Hospital volume can be used as an indicator to predict the postoperative survival of ESCC patients. Our results suggest that the centralized management of esophageal cancer surgery is meaningful to improve the survival of ESCC patients in China, but the hospital volume should preferably not be higher than 1027 cases/year. Hospital volume is considered to be a prognostic factor for many complex diseases. However, the impact of hospital volume on long-term survival after esophagectomy has not been well evaluated in China. Based on a large sample size of 158,618 ESCC patients in China spanning 47 years (1973-2020), We found that hospital volume can be used as a predictor of postoperative survival in patients with ESCC, and identified hospital volume thresholds with the lowest risk of death from all causes. This may provide an important basis for patients to choose hospitals and have a significant impact on the centralized management of hospital surgery.

LINC01232 Facilitates the Proliferation of Esophageal Squamous Cell Carcinoma by Sponging miR-708-5p to Upregulate Upstream Stimulatory Factor 1

LncRNAs are vital regulators in human diseases. LINC01232 is found to be upregulated in esophageal squamous cell carcinoma (ESCC). This study aims to uncover the biological functions of LINC01232 in the development of ESCC and the underlying mechanism. Expression pattern of LINC01232 and its influence on the prognosis in ESCC were determined by analyzing the dataset downloaded from TCGA. LINC01232 levels in ESCC tissues and cell lines were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Regulatory effects of LINC01232 on proliferative and apoptotic abilities in ESCC were examined by Cell Counting Kit (CCK-8) assay, colony formation assay and flow cytometry, respectively. The interaction in the LINC01232/miR-708-5p/USF1 axis was tested by dual-luciferase reporter assay. By analyzing ESCC profiling downloaded from TCGA, LINC01232 was found to be upregulated in ESCC tissues, while its level was unrelated to overall survival and disease-free survival in ESCC patients. LINC01232 was further confirmed to be highly expressed in ESCC tissues and cell lines we collected. Knockdown of LINC01232 inhibited proliferative ability and induced apoptosis in ESCC cells. LINC01232 competed with USF1 to bind miR-708-5p, and thereafter regulated the development of ESCC. LINC01232/miR-708-5p/USF1 axis is responsible for facilitating the proliferative ability in ESCC, thereby aggravating the malignant development of ESCC.

HN1L/AP-2γ/PLK1 signaling drives tumor progression and chemotherapy resistance in esophageal squamous cell carcinoma

Hematological and neurological expressed 1 like (HN1L) is a newly identified oncogene in lung cancer and hepatocellular carcinoma recently identified by our team, but its roles in the development and treatment of esophageal squamous cell carcinoma (ESCC) remain incompletely cataloged. Here, using ESCC tissue array and public database analysis, we demonstrated that HN1L was highly expressed in ESCC tissues, which was associated with tumor tissue invasion, poor clinical stage and short survival for ESCC patients. Loss- and gain-of-function studies in ESCC cells revealed that HN1L enhances ESCC cell metastasis and proliferation in vitro and in mice models. Moreover, high level of HN1L reduces the sensibility of ESCC cells to chemotherapeutic drugs, such as Docetaxel. Mechanism studies revealed that HN1L activated the transcription of polo-like kinase 1 (PLK1) by interacting with transcription factor AP-2γ, which increased the expression of malignancy related proteins Cyclin D1 and Slug in ESCC cells. Blocking PLK1 with inhibitor BI-2356 abrogated the oncogenic function of HN1L and significantly suppressed ESCC progression by combining with chemotherapy. Therefore, this study demonstrates the vital pro-tumor role of HN1L/AP-2γ/PLK1 signaling axis in ESCC, offering a potential therapeutic strategy for ESCC patients with high HN1L by blocking PLK1.

CPT1A promotes anoikis resistance in esophageal squamous cell carcinoma via redox homeostasis

Anoikis resistance was a prominent hallmark of cancer metastasis, and lipo-genic characteristics have been identified as another metabolic alteration during tumorigenesis. However, their crosstalk has not been fully elucidated, especially in advanced esophageal squamous cell carcinoma (ESCC). In this study, we showed, for the first time, that the key enzyme carnitine O-palmitoyl transferase 1 (CPT1A), which is involved in fatty acid oxidation (FAO), was markedly upregulated in ESCC cells upon detached culture via a metabolism PCR array. Overexpression of CPT1A was associated with poor survival of ESCC patients and could protect ESCC cells from apoptosis via maintaining redox homeostasis through supply of GSH and NADPH. Mechanistically, detached culture conditions enhanced the expression of the transcription factor ETV4 and suppressed the expression of the ubiquitin enzyme RNF2, which were responsible for the elevated expression of CPT1A at the mRNA and protein levels, respectively. Moreover, genetic or pharmacologic disruption of CPT1A switched off the NADPH supply and therefore prevented the anchorage-independent growth of ESCC cells in vitro and lung metastases of xenografted tumor models in vivo. Collectively, our results provide novel insights into how ESCC cancer cells exploit metabolic switching to form distant metastases and some evidence for the link between anoikis and FAO.

Loss of miR-637 promotes cancer cell stemness via WASH/IL-8 pathway and serves as a novel prognostic marker in esophageal squamous cell carcinoma

BackgroundEsophageal carcinoma is the highly lethal cancer in the world, predominantly in some areas of East Asia. We previously reported that overexpression of cytoskeleton regulator Wiskott-Aldrich syndrome protein and SCAR Homolog (WASH) associates with poor prognosis of patients with esophageal squamous cell carcinoma (ESCC). However, the molecular mechanism and clinical significance involved in WASH overexpression have not been fully elucidated.MethodsBioinformatics analysis and luciferase reporter assay were used to predict and validate miR-637 as a regulator of WASH in ESCC cell lines. qRT-PCR, Western blotting and ELISA assays were performed to examine RNA expression and protein levels, respectively. Next, the biological functions of miR-637 were explored by tumor sphere formation assay in vitro and nude mouse tumor xenograft in vivo. Finally, we evaluated the association of miR-637 levels with clinical features in ESCC patients.ResultsWe identified miR-637 as a WASH-targeting miRNA. miR-637 mimic strongly attenuated the downstream IL-8 production and tumor sphere formation in esophageal cancer cells, whereas miR-637 inhibitor displayed an opposite effect. IL-8 could facilitate stem-like properties and partially rescue the phenotypes induced by miR-637 mimic. Furthermore, miR-637 inhibitor dramatically promoted IL-8 expression and cancer stemness properties in a WASH-dependent manner. Ectopic expression of miR-637 also inhibited tumor growth in a mouse model. Clinically, low expression of miR-637 was observed in tumor tissues and the low expression levels of miR-637 were correlated with poor survival of ESCC patients. In particular, plasma miR-637 could be used as a noninvasive biomarker for ESCC patients.ConclusionsThese results implicate the potential application of miR-637 for diagnosis and prognosis of esophageal cancer.

Knockdown of RAD51AP1 suppressed cell proliferation and invasion in esophageal squamous cell carcinoma

BackgroundEsophageal cancer is a common malignant tumor of digestive tract with esophageal squamous cell carcinoma (ESCC) being the main histological subtype. This study aimed to identify potential hub gene associated with the pathophysiology of ESCC through bioinformatics analysis and experiment validation.MethodsThree microarray datasets were obtained from the Gene Expression Omnibus (GEO) database. The overlapping differentially expressed genes (DEGs) were analyzed by GEO2R tool. Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) pathway analyses were performed to predict the potential functions of DEGs. Nine hub genes were identified using protein–protein interaction (PPI) network and Cytoscape software. We selected RAD51-associated protein 1 (RAD51AP1) for further research because of its poor prognosis and it has not been sufficiently studied in ESCC. The effects of RAD51AP1 on proliferation, apoptosis, migration and invasion of ESCC cells were determined by in vitro functional assays.ResultsRAD51AP1 expression was significantly upregulated in ESCC tissues compared with normal tissues by using The Cancer Genome Atlas (TCGA) database. High expression of RAD51AP1 was associated with worse survival in ESCC patients. RAD51AP1 expression was positively associated with the enrichment of Th2 cells and T helper cells. Furthermore, CCK-8 and colony formation assays showed knockdown of RAD51AP1 inhibited the proliferation of ESCC cells. Flow cytometry analysis indicated knockdown of RAD51AP1 induced cell cycle arrest and apoptosis in ESCC cells. Transwell assay revealed knockdown of RAD51AP1 suppressed the migration and invasion of ESCC cells.ConclusionsFinally, our results demonstrated that RAD51AP1 silencing significantly inhibited cell proliferation and invasion in ESCC, thereby highlighting its potential as a novel target for ESCC treatment.

LncRNA RPL34-AS1 suppresses the proliferation, migration and invasion of esophageal squamous cell carcinoma via targeting miR-575/ACAA2 axis.

BackgroundLong noncoding RNAs (lncRNAs) are abnormally expressed in a broad type of cancers and play significant roles that regulate tumor development and metastasis. However, the pathological roles of lncRNAs in esophageal squamous cell carcinoma (ESCC) remain largely unknown. Here we aimed to investigate the role and regulatory mechanism of the novel lncRNA RPL34-AS1 in the development and progression of ESCC.MethodsThe expression level of RPL34-AS1 in ESCC tissues and cell lines was determined by RT-qPCR. Functional experiments in vitro and in vivo were employed to explore the effects of RPL34-AS1 on tumor growth in ESCC cells. Mechanistically, fluorescence in situ hybridization (FISH), bioinformatics analyses, luciferase reporter assay, RNA immunoprecipitation (RIP) assay and western blot assays were used to detect the regulatory relationship between RPL34-AS1, miR-575 and ACAA2.ResultsRPL34-AS1 was significantly down-regulated in ESCC tissues and cells, which was negatively correlated with overall survival in ESCC patients. Functionally, upregulation of RPL34-AS1 dramatically suppressed ESCC cell proliferation, colony formation, invasion and migration in vitro, whereas knockdown of RPL34-AS1 elicited the opposite function. Consistently, overexpression of RPL34-AS1 inhibited tumor growth in vivo. Mechanistically, RPL34-AS1 acted as a competing endogenous RNA (ceRNA) of miR-575 to relieve the repressive effect of miR-575 on its target ACAA2, then suppressed the tumorigenesis of ESCC.ConclusionsOur results reveal a role for RPL34-AS1 in ESCC tumorigenesis and may provide a strategy for using RPL34-AS1 as a potential biomarker and an effect target for patients with ESCC.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12885-022-10104-6.

359. INTRATUMORAL MICROBIOME IMPACTS IMMUNE INFILTRATES IN TUMOR MICROENVIRONMENT AND PREDICTS PROGNOSIS IN ESOPHAGEAL SQUAMOUS CELL CARCINOMA PATIENTS

Abstract Emerging evidence suggests different intratumoral microbiome exists in different tumors and plays a crucial function in carcinogenesis. However, whether intratumoral microbiome in esophageal squamous cell carcinoma (ESCC) impacts clinical outcomes and its mechanism remains unclear. 16S rDNA amplicon sequencing was performed on surgical resected samples from 106 ESCC patients including 25 paired tumorous and non-tumorous tissues (NTs) to analyze intratumoral microbiome abundance and its composition. Multiplex fluorescent immunohistochemistry (mfIHC) staining was used to profile the phenotypes of immune infiltrates in tumor microenvironment (TME). Both Shannon index and operational taxonomic units (OTUs), representing alpha-diversity of microbiome, were found significantly lower in tumors comparing to the corresponding NTs. Multivariate analysis revealed that the intratumoral Shannon index, the relative abundance of Lactobacillus and the pTNM stage were independently associated with patients’ overall survival. Furthermore, the relative abundance of Lactobacillus and Shannon index were both positively correlated with the proportions of PD-L1+ epithelial cells (ECs) and tumor-associated macrophages (TAMs, and Shannon index was negatively correlated with the proportions of natural killer cells (NKs) and activated cytotoxic T cells (aCTLs) in TME, indicating an immunosuppressive microenvironment. These findings underscored for the first time that the high abundance of intratumoral Lactobacillus and microbiome alpha-diversity were associated with poor long-term survival of ESCC patients, which might be achieved by increasing PD-L1 + ECs and PD-L1 + TAMs and decreasing aCTLs and NKs in TME.

Caspase-8 mutants activate Nrf2 via phosphorylating SQSTM1 to protect against oxidative stress in esophageal squamous cell carcinoma

Caspase-8, a caspase protein, is involved in the regulation of multiple cell death modes and has a predominant role in cell death. Cancer-associated mutations in the protein-coding region of caspase-8 have been widely reported in several solid tumors and might lead to the loss of its apoptotic function and contribute to the pathogenesis of tumors. However, the specific function and molecular mechanisms of mutant caspase-8 in the development of esophageal squamous cell carcinoma (ESCC) remain unknown. Here, we identified caspase-8 mutants exert tumor-promoting properties in ESCC, patients with the mutants presented a worse prognosis, and caspase-8 mutants lost the suppressive effect on tumor growth in ESCC cells. In addition, we demonstrated that caspase-8 mutants gain a new function of abolishing excess reactive oxygen species (ROS) to maintain ESCC cell growth under oxidative stress. An Nrf2 inhibitor reduced the effects of caspase-8 mutants against oxidative stress. Caspase-8 mutants combined with mTOR to phosphorylate SQSTM1 at Ser349, facilitating the interaction of SQSTM1 and Keap1 and reducing the degradation of the Nrf2 protein. Therefore, our study demonstrated that caspase-8 mutants gain a new function of protecting against oxidative stress via the mTOR/SQSTM1/Keap1/Nrf2 axis in ESCC. Caspase-8 status may be a new prognostic factor for survival in ESCC patients.