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Objective: To compare the clinical efficacy of neoadjuvant chemoradiotherapy (nCRT) and neoadjuvant chemo-immunotherapy (nCIT) for locally advanced esophageal squamous cell carcinoma (ESCC). Methods: Clinical data of patients who received nCRT or nCIT followed by esophagectomy for locally advanced ESCC between January 2010 and December 2022 were retrospectively collected from Zhejiang Cancer Hospital, with 155 patients in the nCRT group and 470 patients in the nCIT group. Propensity score matching (PSM) was performed in the two groups. After PSM, 120 patients were allocated to the nCRT group and 192 patients to the nCIT group. The pathological response and disease recurrence were compared between the two groups after PSM. Log rank test were used to compare the survival outcomes before and after PSM. Univariate and multivariate Cox regression analyses were performed to identify the prognostic factors for locally advanced ESCC. Results: After PSM, the R0 resection rate in the nCRT group and the nCIT group was 93.3% (112/120) and 93.8% (180/192), respectively, with no statistical significance ( P =0.884). However, the pathological complete response rate in the nCRT group [36.7% (44/120)] was higher than that in the nCIT group [21.4% (41/192), P =0.003]. For patients with R0 resection, the major recurrence pattern was distant metastasis [18.8% (21/112)] in the nCRT group, while the pattern was locoregional recurrence [12.2% (22/180)] in the nCIT group. The 3-year disease-free survival rates were 52.7% and 66.1% ( P =0.022) and the 3-year overall survival rates were 59.2% and 75.5% ( P =0.002) in the nCRT and nCIT groups, respectively. Multivariate Cox regression analysis also revealed that the neoadjuvant therapy mode was an independent prognostic factor for patients with locally advanced ESCC. Compared with nCRT, nCIT could significantly prolong disease-free survival ( HR =0.58, 95% CI : 0.40-0.86) and overall survival ( HR =0.53, 95% CI : 0.35-0.79). Conclusion: These results suggest that nCIT could significantly improve disease-free survival rate and overall survival rate over nCRT in locally advanced ESCC, even with lower pathological complete response rate.

Objective: To explore the specific role and molecular mechanism of octamer-binding transcription factor 4 (Oct4) in promoting the progression of esophageal squamous cell carcinoma and radioresistance. Methods: The Gene Expression Profile Data Dynamic Analysis (GEPIA) database was used to analyze the expression differences of the Oct4 gene in different types of tumor tissues and their corresponding adjacent normal tissues. The clinical data and surgical resection tissue specimens of 196 patients with esophageal squamous cell carcinoma who received surgery combined with radiotherapy at Henan Provincial Chest Hospital from January 2013 to May 2022 were collected. Immunohistochemistry was used to detect the expression of Oct4 protein in the tumor and adjacent tissues. The lentiviral packaging system was used to construct esophageal squamous cell carcinoma cell lines that up-regulated or down-regulated Oct4. The cell counting kit 8 (CCK-8) was used to detect the cell proliferation ability, the scratch test was used to detect the cell migration ability, and the clone formation test was used to detect the cell radiosensitivity. Immunofluorescence experiment was used to detect DNA damage level, and Western blot was used to detect the expressions of Oct4, human phosphorylated histone (γ-H2AX), E-cadherin, N-cadherin, vimentin, and zinc finger E box binding homology box 1 (ZEB1). Results: The analysis of GEPIA database showed that the expression level of Oct4 mRNA in esophageal carcinoma was higher than that in paracancerous tissues. The expression level of Oct4 protein in tumor tissues was 78.35±1.42, which was higher than that in adjacent tissues (16.27±0.49). The survival time of patients with a high expression of Oct4 was significantly shorter than that of patients with a low expression of Oct4 (25.40 and 47.00 months). Compared with the control group, the proliferation ability of KYSE510 cells in the Oct4 up-regulated group was enhanced after 72-h culture, and the cell migration ability of these cells was also enhanced, with the migration rate being (41.67±1.20)% vs (23.67±1.86)% after 24-h culture. The radiosensitivity of cells in this group decreased, with the radiosensitivity enhancement ratio being 0.69±0.06 vs 1.00±0.02. After radiotherapy, the expressions of γ-H2AX and E-cadherin decreased, while the expressions of ZEB1, vimentin and N-cadherin increased. Compared with the control group, the proliferation ability of KYSE150 cells in the Oct4 down-regulated groups 1 and 2 decreased (absorbance being 2.51±0.17, 2.38±0.16, and 3.33±0.07, respectively, P ＜0.01) after 72-h culture, and the migration ability also decreased, with the migration rate being (13.33±0.88)%, (13.00±1.00)%, and (40.33±2.03)%, respectively (all P ＜0.001), after 24-h culture. The radiosensitivity was enhanced, with the radiosensitivity enhancement ratio being 1.34±0.11,1.24±0.07, and 1.00±0.02, respectively (all P ＜0.05). After radiotherapy, the expressions of γ-H2AX and E-cadherin increased, while the expressions of ZEB1, vimentin and N-cadherin decreased. Compared with the control group, the proliferation ability of KYSE510 cells in the ZEB1 down-regulated group decreased [absorbance being 1.33±0.15 vs 1.81±0.16 ( P =0.002)] after 72-h culture. The radiosensitivity was enhanced, with the radiosensitivity enhancement ratio being 1.37±0.11 vs 1.00±0.01 ( P =0.037), and after radiotherapy the expression of γ-H2AX increased. Conclusion: Oct4 is involved in the regulation of epithelial-mesenchymal transformation of esophageal squamous cell carcinoma, which promotes the proliferation, migration, and radioresistance of esophageal squamous cell carcinoma.

Objective To explore the impact of M2 macrophages on the malignant biological behavior of esophageal cancer by inhibiting the anti-tumor ability of CD8 + T cells. Methods Using phorbol myristate acetate (PMA) combined with interleukin 4 (IL-4)/IL-13, we induced human monocytic leukemia cells (THP-1) to become M2 macrophages and the detected related inflammatory factors by real-time quantitative PCR. We used magnetic bead sorting to isolate CD8 + T cells from healthy volunteers' peripheral blood, and verified the purity of the sorted cells by flow cytometry. We established a non-contact co-culture system between CD8 + T cells and esophageal squamous carcinoma cells (CD8 + T cell), and established a non-contact co-culture system between M2 macrophages, CD8 + T cells, and esophageal squamous carcinoma cells (M2 macrophages combined with CD8 + T cell). The plate clone formation assay and CCK-8 cell toxicity assay were used to detect the proliferation ability of tumor cells in each group. The Transwell TM assay was used to detect the invasive and migratory abilities of tumor cells in each group. Flow cytometry was used to detect and analyze the apoptosis of tumor cells in each group. GraphPadPrism9.5 software was used for statistical analysis and graphing. Results After induction, the expression of IL-10 and arginase 1 (Arg1) in macrophages was upregulated, while the expression of IL-12 and tumor necrosis factor-alpha (TNF-α) was downregulated, showing the characteristics of M2 macrophages. Peripheral blood CD8 + T cells were successfully selected by magnetic bead sorting, with a positive rate of over 90%. The proliferation, invasion, migration and anti-apoptosis ability of esophageal squamous carcinoma cells co-cultured with CD8 + T cells in the non-contact manner were significantly lower than those of the single cancer cell group; while the proliferation, invasion, migration and the anti-apoptosis ability of esophageal squamous carcinoma cells co-cultured with CD8 + T cells pretreated with M2 macrophage conditioned medium were significantly enhanced compared with those of esophageal squamous carcinoma and CD8 + T cells co-cultured group. Conclusion M2 macrophages promote the proliferation, invasion, migration, and anti-apoptosis of esophageal cancer cells by inhibiting the anti-tumor ability of CD8 + T cells.

Objective: To investigate the mechanism through which RgpB, a virulence factor of Porphyromonas gingivalis (Pg), induces chemoresistance in esophageal squamous carcinoma., Methods: The autophagy-regulating factors that interact with RgpB were screened by immunoprecipitation-mass spectrometry. The interaction between RgpB and the autophagy regulator TBC1D5 was investigated using co-immunoprecipitation. The impact of Pg infection on the expression of esophageal cancer cell membrane receptor molecule Cx43 was assessed using Western blotting. Immunofluorescence assay was used to analyze the relationship among Lamp1, Cx43 and TBC1D5. The effect of Pg infection on autophagosome-lysosome fusion was evaluated using autophagy double fluorescence technique. The effects of Pg infection and a Cx43 inhibitor on proliferation of esophageal cancer cells after chemotherapy were examined with plate cloning assay and CCK-8 method., Results: Immunoprecipitation-mass spectrometry identified TBC1D5 as an autophagy regulator interacting with RgpB, and coimmunoprecipitation suggested that RgpB could directly bind to TBC1D5. In Pg-infected esophageal cancer cells, the expression of Cx43 on the cell membrane was significantly higher than that in non-infected cells. Immunofluorescence assay showed that the expression of Cx43 on the membrane of esophageal cancer cells increased significantly after Pg infection, which blocked autophagosome-lysosome fusion as shown by stubRFP-sensGFP-LC3 lentivirus study. Plate cloning assay and CCK-8 assay showed that the Cx43 inhibitor significantly attenuated the effect of Pg infection for promoting proliferation of esophageal cancer cells after chemotherapy., Conclusion: Pg infection in esophageal cancer blocked autophagosome-lysosome fusion in the tumor cells, thereby preventing Cx43 from lysosomal degradation and leading to chemoresistance of esophageal cancer.

Objective: To investigate the role of an inflammatory microenvironment induced by Porphyromonasgingivalis ( P. gingivalis ) in the occurrence of esophageal squamous cell carcinoma (ESCC) in mice. Methods: A total of 180 C57BL/6 mice were randomly divided into 6 groups, i.e. control group, P. gingivalis group, 4NQO group, 4NQO + P. gingivalis group, 4NQO + P. gingivalis + celecoxib group, and 4NQO + P. gingivalis + antibiotic cocktail (ABC, including metronidazole, neomycin, ampicillin, and vancomycin) group, with 30 mice in each group, using the random number table. All mice were normalized by treatment with ABC in drinking water for 2 weeks. In the following 2 weeks, the mice in the control group and the P. gingivalis group were given drinking water, while the other 4 groups were treated with 30 μg/ml 4NQO in the drinking water. In weeks 11-12, the mice in the P. gingivalis group, the 4NQO + P. gingivalis group, the 4NQO + P. gingivalis + celecoxib group, and the 4NQO + P. gingivalis + ABC group were subjected to ligation of the second molar in oral cavity followed by oral P. gingivalis infection thrice weekly for 24 weeks in weeks 11-34. In weeks 13-34, the mice in 4NQO + P. gingivalis +celecoxib group and 4NQO + P. gingivalis + ABC group were administered with celecoxib and ABC for 22 weeks, respectively. At the end of 34 weeks, gross and microscopic alterations were examined followed by RT-qPCR and immunohistochemistry to examine the expression profiles of inflammatory- and tumor-molecules in esophagi of mice. Results: At 34 weeks, 4NQO treatment alone did not affect the foci of papillary hyperproliferation, diseased area, and the thickness of the esophageal wall, but significantly enhanced the foci of hyperproliferation (median 1.00, P ＜0.05) and mild/moderate dysplasia (median 2.00, P ＜0.01). In addition, the expression levels of IL-6 [8.35(3.45,8.99)], IL-1β [6.90(2.01,9.72)], TNF-α [12.04(3.31,14.08)], c-myc [2.21(1.80,3.04)], pSTAT3, Ki-67, and pH2AX were higher than those in the control group. The pathological changes of the esophageal mucosa were significantly more overt in the 4NQO + P. gingivalis group in terms of the foci of papillary hyperproliferation (median 2.00), diseased area (median 2.51 mm 2 ), the thickness of the esophageal wall (median 172.52 μm), the foci of hyperproliferation (median 1.00, P ＜0.05), and mild/moderate dysplasia (median 1.00, P ＜0.01). In mice of the 4NQO + P. gingivalis group, the expression levels of IL-6 [12.27(5.35,22.08)], IL-1β [13.89(10.04,15.96)], TNF-α [19.56(6.07,20.36)], IFN-γ [11.37(8.23,20.07)], c-myc [2.62(1.51,4.25)], cyclin D1 [4.52(2.68,7.83)], nuclear pSTAT3, COX-2, Ki-67, and pH2AX were significantly increased compared with the mice in the control group. In mice of the 4NQO + P. gingivalis group, the diseased area, invasive malignant foci as well as pSTAT3 and pH2AX expression were significantly blunted by celecoxib. Treatment with ABC markedly reduced the papillary hyperproliferative foci, invasive malignant foci, and pSTAT3 expression but not pH2AX. Conclusions: P. gingivalis promotes the occurrence of esophageal squamous cell carcinoma in mice by inducing an inflammatory microenvironment primed with 4NQO induced DNA damage. Clearance of P. gingivalis with ABC or anti-inflammatory intervention holds promise for prevention of esophageal squamous cell malignant pathogenesis via blockage of IL-6/STAT3 signaling and amelioration of inflammation.

Objective: To explore the role of ferroptosis-related genes in regulating ferroptosis of esophageal squamous cell carcinoma (ESCC)., Methods: ESCC datasets GSE161533 and GSE20347 were downloaded from the Gene Expression Omnibus (GEO) to identify the differentially expressed genes (DEGs) using R software. ESCC ferroptosis-related genes obtained by intersecting the DEGs with ferroptosis-related genes from FerrDb were analyzed using GO and KEGG analyses, protein-protein interaction (PPI) network analysis, and core gene identification through Cytoscape. The identified ferroptosis suppressor genes were validated using TCGA database, and their expression levels were detected using RT-qPCR in cultured normal esophageal cells and ESCC cells. Six ferroptosis suppressor genes (RRM2, GCLC, TFRC, TXN, SLC7A11, and EZH2) were downregulated with siRNA in ESCC cells, and the changes in cell proliferation and apoptosis were assessed with CCK8 assay and flow cytometry; Western blotting was performed to examine the changes in ferroptosis progression of the cells., Results: We identified a total of 58 ESCC ferroptosis-related genes, which involved such biological processes as glutathione transmembrane transport, iron ion transport, and apoptosis and the ferroptosis, glutathione metabolism, and antifolate resistance pathways. The PPI network included 54 nodes and 74 edges with a clustering coefficient of 0.522 and PPI enrichment P <0.001. Cytoscape identified 6 core ferroptosis suppressor genes (RRM2, TFRC, TXN, EZH2, SLC7A11, and GCLC), which were highly expressed in ESCC tissues in the TCGA dataset and in ESCC cell lines. Downregulating these genes in ESCC TE1 cells significantly inhibited cell proliferation, promoted cell apoptosis, reduced the expression levels of ferroptosis markers GPX4 and FIH1, and increased the expression of ACSL4., Conclusion: High expression of ferroptosis suppressor genes in ESCC may cause arrest of ferroptosis progression to facilitate tumor development, and inhibiting these genes can restore ferroptosis and promote cell apoptosis, suggesting their value as potential therapeutic targets for ESCC.

Objective: To investigate the expression of Nanog and its regulatory relationship with MMP-2/MMP-9 proteins in esophageal squamous cell carcinoma (ESCC)., Methods: We detected Nanog and MMP-2/MMP-9 protein expressions in 127 ESCC tissues and 82 adjacent normal tissues using immunohistochemistry and explored their correlations with the clinicopathological parameters and prognosis of the patients. GEO database was utilized to analyze the pathways enriched with the stemness-related molecules including Nanog, and TIMER online tool was used to analyze the correlations among TβR1, MMP-2, and MMP-9 in esophageal cancer., Results: Nanog and MMP-2/MMP-9 proteins were significantly upregulated in ESCC tissues and positively intercorrelated. Their expression levels were closely correlated with infiltration depth and lymph node metastasis of ESCC but not with age, gender, or tumor differentiation. The patients with high expressions of Nanog and MMP-2/MMP-9 had significantly shorter survival time. Bioinformatics analysis showed enrichment of stemness-associated molecules in the TGF-β signaling pathway, and the expressions of MMP-2/MMP-9 and TβR1 were positively correlated. In cultured ESCC cells, Nanog knockdown significantly decreased the expression of TβR1, p-Smad2/3, MMP-2, and MMP-9 and strongly inhibited cell migration., Conclusion: The high expressions of Nanog, MMP-2, and MMP-9, which are positively correlated, are closely related with invasion depth, lymph node metastasis, and prognosis of ESCC. Nanog regulates the expressions of MMP-2/MMP-9 proteins through the TGF-β signaling pathway, and its high expression promotes migration of ESCC cells.

Objective: To explore the function and mechanism of transcription factor En1 in esophageal squamous cell carcinoma (ESCC). Methods: The correlations of En1 with prognosis were analyzed using the overall survival data of 9 397 pan-cancer patients and progression-free survival data of 4 349 pan-cancer patients from The Cancer Genome Atlas (TCGA) database. The En1 expression data in 53 and 155 cases of ESCC and their paired adjacent tissues were from Gene Expression Omnibus (GEO) database and National Genomics Data Center-Genome Sequence Archive(NGDC-GSA)database. Lentivirus was used to generate En1 stable knockout cell lines KYSE180 and KYSE450. The proliferation ability of the cells was detected by cell counting kit 8 and clone formation assay. The migration ability of the cells was detected by Transwell assay. The effect of En1 on the proliferation of ESCC was detected by xenograft experiment in BALB/c-nu/nu mice. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect the expressions of En1, glioma-associated oncogene family zinc finger 1 (GLI1), glioma-associated oncogene family zinc finger 2 (GLI2) and smoothened (SMO). Results: Pan-cancer data from TCGA showed that patients with low En1 expression had longer overall survival and progression-free survival than patients with high En1 expression ( P < 0.001). Data from GEO and GSA databases also showed a high expression level of En1 in ESCC tissues compared with paired tissues ( P ＜0.001). Proliferation was inhibited after knockout of En1 in KYSE180 and KYSE450 cells ( P ＜0.001). The colony formation numbers decreased. The colony formation numbers of KYSE180 cells in the shEn1#1 group and the shEn1#2 group were 138.33±23.07 and 127.00±19.70, respectively, significantly lower than that of the shNC group 340.67±12.06 ( P <0.001). The colony formation numbers of KYSE450 cells in the shEn1#1 group and the shEn1#2 group were 65.33±2.52 and 9.00±3.00, respectively, significantly lower than that of the shNC group 139.00±13.00 ( P <0.001). The migration numbers was inhibited after knockout of En1 [the Transwell numbers of KYSE180 cells in the shEn1#1 group and the shEn1#2 group were 66.67±12.66 and 71.33±11.02, respectively, significantly lower than that of the shNC group 334.67±16.56 ( P <0.001). The Transwell numbers of KYSE450 cells in the shEn1#1 group and the shEn1#2 group were 112.33±14.57 and 54.33±5.51, respectively, significantly lower than that of the shNC group 253.33±21.03 ( P <0.001)]. Xenograft model showed a slower growth rate of shEn1#1 and shEn1#2 cell lines ( P ＜0.001). The tumor weights of KYSE450 cells in the shEn1#1 group and the shEn1#2 group were (0.046±0.026)g and (0.047±0.025)g, respectively, significantly lower than that of the shNC group (0.130±0.038)g ( P ＜0.001). After knockdown of En1, the relative expression levels of GLI1 in KYSE180 cells of the shEn1#1 group and the shEn1#2 group were 0.326±0.162 and 0.322±0.133, and the relative expression levels of GLI1 in KYSE450 cells of the shEn1#1 and shEn1#2 groups were 0.131±0.006 and 0.352±0.050, respectively, which were all lower than that in the shNC group ( P ＜0.01). After knockdown of En1, overexpression of GLI1 attenuated the inhibitory effect of knockdown of En1 on cell proliferation ( P ＜0.001), colony formation[the colony formation numbers of the shEn1#1-GLI1 group were 151.00±9.54, higher than 102.33±10.02 ( P =0.004) of the shEn1#1-vector group] and migration [the migration numbers of the shEn1#1-GLI1 group were 193.67±10.07, higher than 109.33±11.50 ( P< 0.001) in the shEn1#1-vector group]. In clinical samples of ESCC, major regulatory factors of the Hedgehog pathway were up-regulated and the pathway was activated. Conclusion: En1 promotes the proliferation and migration of ESCC cells by regulating the Hedgehog pathway and can be used as a new potential target for targeted therapy of ESCC.

Objective: To investigate the role and the mechanism of Ras-associated binding protein23 (RAB23) in the migration and invasion of esophageal squamous cell carcinoma (ESCC) cells. Methods: RAB23 mRNA levels were measured in 16 pairs of ESCC and adjacent normal tissues via real-time polymerase chain reactions. RAB23 mRNA levels in the ESCC and adjacent normal tissues of dataset GSE20347 deposited in the Gene Expression Omnibus (GEO) database were also analyzed. Immunohistochemistry (IHC) was used to detect the RAB23 protein expressions in 106 pairs of ESCC and adjacent normal tissues, as well as in the lymph glands and primary tumor tissues of 33 patients with positive lymph nodes and 10 patients with negative lymph nodes. Endogenous RAB23 expression was transiently depleted using siRNAs (si-NC, si-RAB23-1, and si-RAB23-9) or stably reduced using shRNAs (sh-NC and sh-RAB23) in ESCC KYSE30 and KYSE150 cells, and the knockdown efficiency was tested using Western blot assays. Cell counting kit-8 assays and mouse xenograft models were used to test the proliferation of ESCC cells . Transwell assays and tail vein-pulmonary metastasis models in immunocompromised mice were used to examine the migration and invasion of ESCC cells. Cell adhesion assays were used to test the adhesion of ESCC cells. RNA-seq assays were used to analyze how RAB23 knockdown influenced the expression profile of ESCC cells and the implicated signal pathways were confirmed using Western blot assays. Results: The RAB23 mRNA expression in 16 cases of ESCC tissues was 0.009 7±0.008 9, which was markedly higher than that in adjacent normal tissues (0.003 2±0.003 7, P =0.006). GEO analysis on RAB23 expressions in ESCC and adjacent normal tissues showed that the RAB23 mRNA level in ESCC tissues (4.30±0.25) was remarkably increased compared with their normal counterparts (4.10±0.17, P= 0.037). Among the 106 pairs of ESCC and tumor-adjacent normal tissues, 51 cases exhibited low expression of RAB23 and 55 cases showed high expression of RAB23, whereas in the paired tumor-adjacent normal tissues 82 cases were stained weakly and 24 strongly for RAB23 protein. These results indicated that RAB23 expression was markedly increased in ESCC tissues ( P <0.001). Additionally, only 1 out of 33 primary ESCC tissues with positive lymph nodes showed low RAB23 protein expression. On the other hand, 7 samples of primary ESCC tissues with negative lymph nodes were stained strongly for RAB23 while its level in the other 3 samples was weak. These results showed that RAB23 expression was remarkably increased in primary ESCC tissues with positive lymph nodes compared with those with negative lymph nodes ( P =0.024). Further tests showed that 32 out of 33 positive lymph nodes were stained strongly for RAB23, whereas no negative lymph nodes ( n =10) exhibited high expression of RAB23 ( P <0.001). Both transient and stable knockdown of endogenous RAB23 expression failed to cause detectable changes in the proliferation of KYSE30 cells in vitro and in vivo , but attenuated the migration and invasion of KYSE30 cells as well as the invasion of KYSE150 cells. RAB23 knockdown was found to significantly decrease the number of adhesive KYSE30 cells in the sh-RAB23 group (313.75±89.34) compared with control cells in the sh-NC group (1 030.75±134.29, P <0.001). RAB23 knockdown was also found to significantly decrease the number of adhesive KYSE150 cells in the sh-RAB23 group (710.5±31.74) compared with the number of control cells in the sh-NC group (1 005.75±61.09, P <0.001). RNA-seq assays demonstrated that RAB23 knockdown using two siRNAs targeting RAB23 mRNA markedly impaired focal adhesion-related signal pathways, and decreased the levels of phosphorylated FAK (p-FAK) and phosphorylated paxillin (p-paxillin) in KYSE30 and KYSE150 cells. Conclusions: Significantly increased RAB23 in ESCC tissues positively correlates with lymph node metastasis. Depleted RAB23 expression attenuates focal adhesion-related signal pathways, thus impairing the invasion, metastasis, and adhesion of ESCC cells.

Objective: To investigate the application value of computed tomography (CT) examination of lymph node short diameter in evaluating cardia-left gastric lymph node metastasis in thoracic esophageal squamous cell carcinoma (ESCC). Methods: A total of 477 patients with primary thoracic ESCC who underwent surgical treatment in the Affiliated Cancer Hospital of Zhengzhou University from January 2013 to December 2017 were collected. All of them underwent McKeown esophagectomy plus complete two-field or three-field lymph node dissection. Picture archiving and communication system were used to measure the largest cardia-left gastric lymph node short diameter in preoperative CT images. The postoperative pathological diagnosis results of cardia-left gastric lymph node were used as the gold standard. Receiver operating characteristic (ROC) curve was used to evaluate the efficacy of CT lymph node short diameter in detecting the metastasis of cardia-left gastric lymph node in thoracic ESCC, and determine the optimal cut-off value. Results: The median short diameter of the largest cardia-left gastric lymph node was 4.1 mm in 477 patients, and the largest cardia-left gastric lymph node short diameter was less than 3 mm in 155 cases (32.5%). Sixty-eight patients had cardia-left gastric lymph node metastases, of which 38 had paracardial node metastases and 41 had left gastric node metastases. The lymph node ratios of paracardial node and left gastric node were 4.0% (60/1 511) and 3.3% (62/1 887), respectively. ROC curve analysis showed that the area under the curve of CT lymph node short diameter for evaluating cardia-left gastric lymph node metastasis was 0.941 (95% CI: 0.904-0.977; P <0.05). The optimal cut-off value of CT examination of the cardia-left gastric lymph node short diameter was 6 mm, and the corresponding sensitivity, specificity and accuracy were 85.3%, 91.7%, and 90.8%, respectively. Conclusion: CT examination of lymph node short diameter can be a good evaluation of cardia-left gastric lymph node metastasis in thoracic ESCC, and the optimal cut-off value is 6 mm.

Objective: To understand the characteristics and influencing factors of lymph node metastasis of the right recurrent laryngeal nerve in thoracic esophageal squamous cell carcinoma (ESCC), and to explore the reasonable range of lymph node dissection and the value of right recurrent laryngeal nerve lymph node dissection. Methods: The clinicopathological data with thoracic ESCC were retrospectively analyzed, and the characteristics of lymph node metastasis along the right recurrent laryngeal nerve and its influencing factors were explored. Results: Eighty out of 516 patients had lymph node metastasis along the right recurrent laryngeal nerve, the metastasis rate was 15.5%. Among 80 patients with lymph node metastasis along the right recurrent laryngeal nerve, 25 cases had isolated metastasis to the right recurrent laryngeal nerve lymph node but no other lymph nodes. The incidence of isolated metastasis to the recurrent laryngeal nerve lymph node was 4.8% (25/516). A total of 1 127 lymph nodes along the right recurrent laryngeal nerve were dissected, 115 lymph nodes had metastasis, and the degree of lymph node metastasis was 10.2%. T stage, degree of tumor differentiation and tumor location were associated with right paraglottic nerve lymph node metastasis (all P <0.05). The lymph node metastasis rate along the right recurrent laryngeal in patients with upper thoracic squamous cell carcinoma (23.4%, 26/111) was higher than that of patients with middle (13.5%, 40/296) and lower (12.8%, 14/109) thoracic squamous cell carcinoma ( P =0.033). In patients with poorly differentiated ESCC (20.6%, 37/180) the metastasis rate was higher than that of patients with moderately (14.6%, 39/267) and well-differentiated (5.8%, 4/69; P <0.05). The lymph node metastasis rate of patients with stage T4 (27.3%, 3/11) was higher than that of patients with stage T1 (9.6%, 19/198), T2 (19.0%, 16/84) and T3 (18.8%, 42/1 223; P <0.05). Multivariate regression analysis showed that tumor location ( OR =0.61, 95% CI: 0.41-0.90, P =0.013), invasion depth ( OR =1.46, 95% CI: 1.11-1.92, P =0.007), and differentiation degree ( OR =1.67, 95% CI: 1.13-2.49, P =0.011) were independent risk factors for lymph node metastasis along right recurrent laryngeal nerve of ESCC. Conclusions: The lymph node along the right recurrent laryngeal nerve has a higher rate of metastasis and should be routinely dissected in patients with ESCC. Tumor location, tumor invasion depth, and differentiation degree are risk factors for lymph node metastasis along right recurrent laryngeal nerve in patients with ESCC.

Objective: To analyze clinicopathological features of circumferential superficial esophageal squamous cell carcinoma and precancerous lesions and investigate the risk factors for deep submucosal invasion and angiolymphatic invasion retrospectively. Methods: A total of 116 cases of esophageal squamous epithelial high-grade intraepithelial neoplasia or squamous cell carcinoma diagnosed by gastroscopy, biopsy pathology and endoscopic resection pathology during November 2013 to October 2021 were collected, and their clinicopathological features were analyzed. The independent risk factors of deep submucosal invasion and angiolymphatic invasion were analyzed by logistic regression model. Results: The multivariate logistic regression analysis showed that drinking history ( OR =3.090, 95% CI: 1.165-8.200; P <0.05), The AB type of intrapapillary capillary loop (IPCL) ( OR =11.215, 95% CI: 3.955-31.797; P <0.05) were the independent risk factors for the depth of invasion. The smoking history ( OR =5.824, 95% CI: 1.704-19.899; P <0.05), the presence of avascular area (AVA) ( OR =3.393, 95% CI: 1.285-12.072; P <0.05) were the independent factors for the angiolymphatic invasion. Conclusions: The risk of deep submucosal infiltration is greater for circumferential superficial esophageal squamous cell carcinoma patients with drinking history and IPCL type B2-B3 observed by magnifying endoscopy, while the risk of angiolymphatic invasion should be vigilant for circumferential superficial esophageal squamous cell carcinoma patients with smoking history and the presence of AVA observed by magnifying endoscopy. Ultrasound endoscopy combined with narrowband imagingand magnification endoscopy can improve the accuracy of preoperative assessment of the depth of infiltration of superficial squamous cell carcinoma and precancerous lesions and angiolymphaticinvasion in the whole perimeter of the esophagus, and help endoscopists to reasonably grasp the indications for endoscopic treatment.

Objective: To explore the influence factors of poor prognosis of esophageal squamous cell carcinoma (ESCC) and the predictive value of inflammatory reaction indexes including neutrophils and lymphocytes ratio (NLR), platelet and lymphocyte ratio (PLR), monocyte and lymphocyte ratio (MLR) provision and differentiation degree, infiltration depth, lymph node metastasis number on the postoperative recurrence of ESCC. Methods: A total of 130 patients with ESCC who underwent radical resection from February 2017 to February 2019 in Nanyang Central Hospital were selected and divided into good prognosis group (66 cases) and poor prognosis group (64 cases) according to the prognostic effect. The clinical data and follow-up data were collected. Multivariate logistic regression analysis was used to determine the independent influencing factors of poor prognosis. Spearman correlation analysis was used to determine the correlation between preoperative NLR, PLR and MLR with the degree of differentiation, depth of invasion and number of lymph node metastases. Receiver operating characteristic (ROC) curve analysis was used to evaluate the efficacy of NLR, PLR and MLR in predicting poor prognosis of ESCC. Results: Univariate analysis showed that the degree of differentiation, the degree of invasion and the number of lymph node metastasis were related to the prognoses of patients with ESCC ( P <0.05). Multivariate logistic regression analysis showed that the degree of differentiation, depth of invasion and number of lymph node metastases were independent influencing factors for poor prognosis of patients with ESCC, moderate differentiation ( OR =2.603, 95% CI: 1.009-6.715) or low differentiation ( OR =9.909, 95% CI: 3.097-31.706), infiltrating into fibrous membrane ( OR =14.331, 95% CI: 1.333-154.104) or surrounding tissue ( OR =23.368, 95% CI: 1.466-372.578), the number of lymph node metastases ≥ 3 ( OR =9.225, 95% CI: 1.693-50.263) indicated poor prognosis. Spearman correlation analysis showed that NLR was negatively correlated with the degree of differentiation and the number of lymph node metastases ( r =-0.281, P =0.001; r =-0.257, P =0.003), PLR was negatively correlated with the degree of differentiation, depth of invasion and number of lymph node metastasis ( r =-0.250, P =0.004; r =0.197, P =0.025; r =-0.194, P =0.027), MLR was positively correlated with the degree of differentiation and the number of lymph node metastasis ( r =0.248, P =0.004; r =0.196, P =0.025). ROC curve analysis showed that the areas under the curve of NLR, PLR and MLR in predicting poor prognosis of ESCC were 0.971, 0.925 and 0.834, respectively. The best cut-off value of NLR was 2.87. The sensitivity and specificity of NLR in predicting poor prognosis of ESCC were 90.6% and 87.9%, respectively. The optimal cut-off value of PLR was 141.75. The sensitivity and specificity for predicting poor prognosis of ESCC were 92.2% and 87.9%, respectively. The best cut-off value of MLR was 0.40. The sensitivity and specificity of MLR in predicting poor prognosis of esophageal squamous cell carcinoma were 54.7% and 100.0%, respectively. Conclusions: The degree of differentiation, the degree of invasion and the number of lymph node metastases are closely related to the poor prognosis of patients with esophageal squamous cell carcinoma. NLR, PLR and MLR can provide important information for predicting the poor prognosis of esophageal squamous cell carcinoma.

Objective: To explore the function and mechanism of long non-coding RNA MIR503HG in esophageal squamous cell carcinoma (ESCC). Methods: The MIR503HG expression data in 60, 119 and 23 cases of ESCC and their paired adjacent tissues were chosen from three ESCC datasets GSE53622, GSE53624 and GSE130078, respectively. The expression data of MIR503HG in 81 ESCC tissues and 271 unpaired normal esophageal tissues were screened from the combined dataset of Cancer Genome Atlas and Genotype-Tissue Expression Database (TCGA+ GTEx). The MIR503HG knockdown plasmid was constructed, packaged into lentivirus. The lentivirus was used to infect with esophageal squamous cell carcinoma cell lines KYSE30 and KYSE510 to screen out the stable MIR503HG knockdown cell lines. ESCC cell line KYSE30 was transiently transfected with miRNA mimics to overexpress hsa-miR-503-3p and hsa-miR-503-5p.The expression levels of MIR503HG, hsa-miR-503-3p and hsa-miR-503-5p were detected by quantitative real-time polymerase chain reaction. The proliferation ability of the cells was detected by cell counting kit 8 and clone formation assay. The invasion and migration ability of the cells were detected by Transwell assay. Cell cycle was detected by flow cytometry. The effect of MIR503HG on the proliferation of ESCC was detected by xenograft experiment in BALB/c-nu/nu mice. Results: Both GEO and TCGA+ GTEx databases showed that the expression of MIR503HG in ESCC tissues was higher than that in adjacent tissues and normal esophageal tissues ( P <0.01). Compared with shNC group, the proliferation rates of KYSE30 and KYSE510 cells after knockdown of MIR503HGwere significantly inhibited ( P <0.001). The colony formation numbers of KYSE30 cells in shMIR503HG1 group and shMIR503HG2 group were (2.00±1.41) and (1.33±0.47), respectively, significantly lower than that of the shNC group ( P =0.002). The clone formation numbers of KYSE510 cells in shMIR503HG1 group and shMIR503HG2 group were (174.67±15.97) and (80.33±6.34), respectively, significantly lower than that of the shNC group ( P <0.001). The invasive numbers of KYSE30 cells in shMIR503HG1 group and shMIR503HG2 group were 75.33±6.02 and 45.67±7.59, significantly lower than that of the shNC group( P <0.001). The migrating number of KYSE30 cells in shMIR503HG1 group and shMIR503HG2 group were 244.00±10.23 and 210.67±13.52, significantly lower than that of the shNC group( P <0.001), and the cell cycle was arrested in G(0)/G(1) phase. The xenograft experiment showed that the subcutaneous tumor in shMIR503HG group was significantly smaller than that in shNC group, and the tumor weight in shMIR503HG group was (0.097±0.026) g, which was lower than (0.166±0.021) g in shNC group ( P <0.001). After knockdown of MIR503HG, the relative expression levels of hsa-miR-503-3p in KYSE30 cells of shMIR503HG1 group and shMIR503HG2 group were 0.66±0.02 and 0.58±0.00, respectively, the relative expression levels of hsa-miR-503-5p were 0.64±0.00 and 0.68±0.03, respectively, which were all lower than those in shNC group ( P <0.01). After knockdown of MIR503HG, overexpression of hsa-miR-503-3p and hsa-miR-503-5p attenuated the inhibitory effects of knockdown of MIR503HG on proliferation ( P <0.001), invasion ( P <0.01) and migration ( P <0.001) of KYSE30 cells. Conclusions: MIR503HG promotes the proliferation, invasion and migration of ESCC cells by regulating hsa-miR-503 pathway and can be used as a new potential target for targeted therapy of ESCC.

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ 2 test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.

Objective: To investigate the effects of 5-tetradecanoxy 2-furanic acid (TOFA) on cell proliferation, cell cycle and apoptosis of esophageal squamous cell carcinoma (ESCC) cells. Methods: Eca-109 cells and KYSE-450 cells were divided into control group (DMSO) and experimental group (TOFA), respectively. The cells (4×10 3 cells/100 μl) were inoculated into 96-well plates with 5 multiple wells at each concentration. After 24 h culture, cells were treated with DMSO or different concentrations (1, 3, 5, 10 μg/ ml) of TOFA for 24, 48 and 72 h. Cell proliferation was detected by MTT, cell cycle and apoptosis were detected by flow cytometry, the expression levels of p21 and Cleaved caspase-3 and modification levels of p-Akt, p-mTOR and p-4EBP1 were detected by Western blot, and intracellular free fatty acids were detected by special kits. Results: MTT results showed that TOFA inhibited the proliferation of Eca109 and KYSE-450 cells in a concentration and time dependent manner (all P<0.05), with IC 50 of 4.65 μg/ml and 3.93 μg/ml for 48 h, respectively. Flow cytometry results showed that compared with DMSO group, the percentage of cells in G2/M phase was increased and the apoptosis rate was increased in the experimental group. Western blotting results showed that compared with DMSO group, p21 and Cleaved caspase-3 protein expression levels were up-regulated, and p-AKT, p-mTOR and p-4EBP1 protein expression levels were down-regulated (all P<0.05). Conclusion: TOFA inhibits the proliferation, blocks the cycle progression and promotes apoptosis of ESCC, the mechanism may be related to the AKT/mTOR/4EBP1 signaling pathway.

Objective: To evaluate the survival and prognostic factors of radiotherapy in patient with Ⅳ stage esophageal squamous carcinoma treated with radiation or chemoradiation. Methods: The medical records of 608 patients with stage Ⅳ esophageal squamous cell carcinoma who met the inclusion criteria in 10 medical centers in China from 2002 to 2016 were retrospectively analyzed. The overall survival and prognostic factors of all patients at 1, 3 and 5 years were analyzed. Results: The 1-, 3-, 5- year overall survival (OS) rates was 66.7%, 29.5% and 24.3% in stage ⅣA patients, and 58.8%, 29.0% and 23.5% in stage ⅣB patients. There was no statistical difference between the two groups ( P =0.255). Univariate analysis demonstrated that the length of lesion, treatment plan, planned tumor target volume (PGTV) dose, subsequent chemotherapy, and degrees of anemia, radiation esophagitis, radiation pneumonia were related to the prognoses of patients with Ⅳ stage esophageal carcinomas after radiotherapy and chemotherapy ( P <0.05). Multivariate analysis demonstrated that PGTV dose ( OR =0.693, P =0.004), radiation esophagitis ( OR =0.867, P =0.038), and radiation pneumonia ( OR =1.181, P =0.004) were independent prognostic factors for OS. Conclusions: For patients with stage Ⅳ esophageal squamous cell carcinoma, chemoradiotherapy followed by sequential chemotherapy is recommended, which can extend the total survival and improve the prognosis of the patients. PGTV dose more than 60 Gy has better efficacy.

Objective: To investigate the effects of microRNA-182-5p (miR-182-5p) on cell proliferation and invasion of esophageal squamous cell carcinoma (ESCC) and its related molecular mechanisms. Methods: Real-time quantitative polymerase chain reaction (RT-qPCR) was employed to detect the miR-182-5p expression in ESCC tissues and cells. MiR-182-5p inhibitor, miR-182-5p mimic and negative control (NC) were transfected into ESCC Eca109 and TE1 cells, and miR-182-5p expression after transfection was examined using RT-qPCR. Cell counting kit-8 (CCK-8) was utilized to investigate the cell proliferation and Transwell chamber was used to detect the cell invasion ability. Dual-luciferase reporter assay was used to detect the direct interaction of miR-182-5p and cell adhesion molecule 2 (CADM2), RT-qPCR was employed to detect CADM2 expression in ESCC tissues, the correlation between CADM2 and miR-182-5p was also examined. Finally, western blot was used to detect the protein expressions of CADM2, focal adhesion kinase (FAK), p-Akt and Akt after transfection. Results: The miR-182-5p level in ESCC tissues was (2.180±1.295), significantly higher than (0.890±0.284) in normal esophageal epithelial tissues ( P <0.001). The survival ratio of ESCC patients with high miR-182-5p level was evidently lower than that of ESCC patients with low miR-182-5p level ( P <0.05). MiR-182-5p expression was significantly associated with TNM staging and lymph node metastasis ( P <0.05). The expressions of miR-182-5p in ESCC cells including EC9706, Eca109, TE1, KYSE450 and KYSE70 were (2.449±0.082), (2.965±0.088), (4.873±0.258), (1.338±0.045) and (1.999±0.082), respectively, obviously higher than (0.989±0.087) in normal esophageal epithelial cell Het-1A (all P <0.01). Besides, miR-182-5p inhibitor significantly downregulated the miR-182-5p expression in Eca109 and TE1, and suppressed cell proliferation and invasion ability. Conversely, miR-182-5p mimic significantly upregulated the miR-182-5p expression in Eca109 and TE1, and promoted cell proliferation and invasion ability. Dual-luciferase reporter assay revealed that co-transfection of CADM2-3'UTR-WT and miR-182-5p mimic significantly reduced the luciferase activities in Eca109 and TE1 cells ( P <0.01), and CADM2 was the direct target of miR-182-5p. The expression of CADM2 in ESCC tissues was (0.190±0.143), markedly lower than (0.845±0.327) in normal esophageal epithelial tissues ( P <0.001). The miR-182-5p level exhibited negative correlation with CADM2 level in ESCC tissues ( r =-0.5004, P <0.001). In addition, CADM2 expression was closely correlated with TNM staging and lymph node metastasis ( P <0.05). The survival ratio of ESCC patients with high CADM2 level was evidently higher than that of ESCC patients with low CADM2 level ( P <0.05). MiR-182-5p inhibitor significantly upregulated the expression of CADM2 protein, but suppressed the protein expressions of FAK, p-Akt and Akt, whereas miR-182-5p mimic markedly downregulated the expression of CADM2 protein, but promoted the protein expressions of FAK, p-Akt and Akt. Conclusion: MiR-182-5p is implicated in the carcinogenesis and development of ESCC, and thus may be a potential molecular target for ESCC patients.

Objective: To explore the safety and short-term and long-term efficacy of robot-assisted radical esophageal cancer surgery. Methods: A prospective randomized controlled trial was conducted. Patients who were preoperatively diagnosed as stage 0-IIIB esophageal squamous cell carcinoma and suitable for minimally invasive surgery in our hospital from January 1, 2014 to June 30, 2018 were prospectively enrolled. Those of age ≥75 years having received preoperative neoadjuvant therapy, contradicted to anesthesia or operation due to severe complications, with history of thoracotomy or laparotomy, with concurrent malignant tumors, without complete informations or refusing to participate in this study were excluded. Participants were randomly divided into the thoracoscopy-laparoscopy group and the robot group using a random number table in ratio of 1:1. Preoperative clinicopathological data, surgical data and postoperative outcomes were recorded. The patients were followed up mainly by telephone. Follow-up endpoint was recurrence of esophageal cancer and death. Kaplan-Meier method was used to estimate survival rate. The survival difference between the two groups was analyzed using the log-rank test. Results: According to above criteria, a total of 192 esophageal cancer patients were enrolled finally, including 144 males and 48 females with mean age of (61.9±8.6) years. The robot group had 94 cases, including 72 males and 22 females with mean age of (61.3±8.2) years, and the thoracoscopy-laparoscopy group had 98 cases, including 72 males and 26 females with mean age of (62.4±9.1) years. There were no significant differences in baseline data between the two groups (all P >0.05). Operation was abandoned in one case in each group due to extensive pleural cavity metastasis and one case in each group was converted to thoracotomy. The success rate of operation was 97.9% (92/94) in the robot group and 98.0% (96/98) in the thoracoscopy-laparoscopy group (χ(2)=0.002, P =0.996). The number of lymph nodes dissected in the robot group was significantly higher than that in the thoracoscopy-laparoscopy group (29.2±12.5 vs. 22.8±13.3, t =3.433, P =0.001), while there were no significant differences in operative time, intraoperative blood loss, R0 resection rate, postoperative 30-day mortality, postoperative hospital stay, ICU stay, time to withdrawal of chest drainage tube, ICU readmission, and postoperative morbidity of complications between the two groups (all P >0.05). The median follow-up time was 21 (3 to 57) months. During the follow-up, 3 cases and 4 cases were lost, and 2 cases and 3 cases died of other diseases in the robot group and in the thoracoscopy-laparoscopy group respectively. Recurrence occurred in 39 cases during follow-up, including 14 recurrences in the robotic group with 1- and 3-year recurrence-free survival rates of 92.4% and 87.6% respectively and the median recurrence time of 15 (9 to 42) months. There were 25 recurrences in the thoracoscopy-laparoscopy group with 1- and 3-year recurrence-free survival rates of 81.7% and 67.9% respectively and the median recurrence time of 9 (3 to 42) months. There was significant difference in recurrence-free survival between the two groups (χ(2)=4.193, P =0.041). Conclusions: The robotic surgical system has good oncology effect and surgical safety in the radical operation of esophageal cancer, which deserves further research and promotion.

Objective: To evaluate the prognostic factors of T1-2N0M0 esophageal squamous cell carcinoma (ESCC) treated with definitive radiotherapy. Methods: The clinical data of 196 patients with T1-2N0M0 ESCC who were treated with definitive radiotherapy in 10 hospitals were retrospectively analyzed. All sites were members of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG). Radiochemotherapy were applied to 78 patients, while the other 118 patients received radiotherapy only. 96 patients were treated with three-dimensional conformal radiotherapy (3DCRT) and 100 treated with intensity-modulated radiotherapy (IMRT). The median dose of plan target volume(PTV) and gross target volume(GTV) were both 60 Gy. The median follow-up time was 59.2 months. Log rank test and Cox regression analysis were used for univariat and multivariate analysis, respectively. Results: The percentage of normal lung receiving at least 20 Gy (V(20)) was (18.65±7.20)%, with average dose of (10.81±42.05) Gy. The percentage of normal heart receiving at least 30 Gy (V(30)) was (14.21±12.28)%. The maximum dose of exposure in spinal cord was (39.65±8.13) Gy. The incidence of radiation pneumonia and radiation esophagitis were 14.80%(29/196) and 65.82%(129/196), respectively. The adverse events were mostly grade 1-2, without grade 4 toxicity. Median overall survival (OS) and progression-free survival (PFS) were 70.1 months and 62.3 months, respectively. The 1-, 3- and 5-year OS rates of all patients were 75.1%、57.4% and 53.2%, respectively. The 1-, 3- and 5-year PFS rates were 75.1%、57.4% and 53.2%, respectively. Multivariate analysis demonstrated that patients'age ( HR =1.023, P =0.038) and tumor diameter ( HR =1.243, P =0.028)were the independent prognostic factors for OS, while tumor volume were the independent prognostic factor for PFS. Conclusions: Definitive radiotherapy is a promising therapeutic method in patients with T1-2N0M0 ESCC. Patients' age, tumor diameter and tumor volume may impact patients' prognosis.

Objective: To explore the expression of microRNA-17-5p (miR-17-5p) in esophageal squamous cell carcinoma (ESCC) and its effects on cell proliferation and invasion ability. Methods: Real-time quantitative PCR (RT-qPCR) was used to detect the miR-17-5p level in ESCC tissues and cells. MiR-17-5p inhibitor and negative control (NC) were transfected into EC9706 and TE1 cells, and miR-17-5p expression was examined by using RT-qPCR. Cell counting kit-8 (CCK-8) and EdU were conducted to detect cell proliferation and Transwell chamber was used to investigate cell invasion ability. Dual-luciferase reporter assay was used to detect the direct interaction of miR-17-5p and retinoblastoma-like protein-2 (RBL2). Western blot and RT-qPCR were used to detect the expression of RBL2 in ESCC tissues, respectively. Finally, the correlation between RBL2 and miR-17-5p was analyzed. Results: The miR-17-5p level in ESCC tissues was 4.222±0.392, significantly higher than 1.081±0.046 in normal esophageal epithelial tissues ( P <0.001). The expressions of miR-17-5p in ESCC cells, including EC9706, Eca109, TE1, KYSE450, KYSE70 and KYSE520, were 13.84±1.266, 6.453±0.293, 11.41±0.520, 2.613±0.548, 5.251±0.239 and 4.251±0.195, respectively, all obviously higher than (1.007±0.079) in normal esophageal epithelial cell Het-1A ( P <0.05). The miR-17-5p level in patients with ESCC Ⅲ~Ⅳ was 5.094±0.562, markedly higher than 2.934±0.364 in patients with ESCCⅠ~Ⅱ( P <0.01). Moreover, the miR-17-5p level in ESCC patients with lymph node metastasis was 5.523±0.634, markedly higher than 3.533±0.461 in ESCC patients without lymph node metastasis ( P <0.05). The survival ratio of ESCC patients with higher miR-17-5p level was evidently lower than that of ESCC patients with lower miR-17-5p level ( P <0.05). MiR-17-5p inhibitor significantly downregulated the miR-17-5p expression in EC9706 and TE1, which suppressed cell proliferation and invasion ability. Dual-luciferase reporter assay revealed that co-transfection of 3' untranslated region-wild type (3'UTR-WT) of RBL2 and miR-17-5p mimic significantly reduced luciferase activity in EC9706 and TE1 cells ( P <0.01), which implicated that RBL2 was the direct target of miR-17-5p. The result of western blot revealed that RBL2 protein expressions in miR-17-5p group of EC9706 and TE1 cells were 0.936±0.055 and 0.923±0.048, obviously higher than 0.087±0.019 and 0.102±0.010 in control group ( P <0.001). The expression of RBL2 in ESCC tissues was 0.219±0.510, markedly lower than 0.983±0.324 in normal esophageal epithelial tissues ( P <0.001). The miR-17-5p level exhibited a negative correlation with RBL2 level in ESCC tissues ( r =-0.462, P <0.001). Downregulation of RBL2 reversed the miR-17-5p inhibitor induced suppression of cell proliferation and invasion ability. Conclusion: MiR-17-5p participates in the carcinogenesis and development of ESCC, thus may be a potential therapeutic target for ESCC patients.

Objective: To analyze the related factors of esophageal squamous cell carcinoma and precancerous lesions among residents aged 40-69 years old in rural areas of Shandong Province. Methods: In October 2018, 300 villages in 13 counties of the Shandong upper gastrointestinal cancerearly diagnosis and treatment projectin 2017 were selected as research areas, and 30 400 residents aged 40-69 were recruited in this study. The demographic characteristics, health status and lifestyle information were collected through the questionnaire survey, and endoscope iodine staining and indicative biopsy methods were used for cancer screening among eligible people.The multivariate logistic regression model was used to analyze the risk factors for esophageal cancer and precancerous lesions. Results: The subjects in this study were (56.42±7.24) years old, including 13 193 males (43.40%).There were 936 cases of esophageal cancer and precancerous lesions (3.08%), including 521 males and 415 females.Compared with women, 40-49 years old, high level education, drinking tap water, regular intake of meat, eggs and milk, and family average annual income more than 30 000 RMB, men ( OR= 1.90, 95 %CI : 1.65-2.19), 60-69 years old ( OR= 5.28, 95 %CI : 4.11-7.30), primary school education or below ( OR= 1.50, 95 %CI : 1.20-1.89), drinking groundwater ( OR= 1.71, 95 %CI : 1.38-2.13), never eating meat, eggs and milk ( OR= 1.48, 95 %CI : 1.22-1.80), and family average annual income less than 30 000 RMB ( OR= 1.41, 95 %CI : 1.16-1.70) would increase the risk of esophageal cancer and precancerous lesions. Conclusion: The gender, age, educational level, annual household income, drinking water source, the frequency of eating meat, egg and milk were related to the occurrence of esophageal cancer and precancerous lesions among 40-69 years old residents in rural areas of Shandong Province.

Abnormal genomic DNA methylation is an important epigenetic change in malignant tumors. Esophageal squamous cell cancer is one of common malignant tumors in our country. In this paper summarized and discussed the progress of genomic DNA methylation in the esophageal squamouscell cancer, including the level of genomic DNA methylation, frequent abnormally methylated genes, methylation markers and potential targets, etc. This paper might provide candidate biomarkers and targets for further studies on the mechanism of the tumorigenesis and development of the esophagealsquamouscell cancer, as well as for the clinical application of esophageal cancer.

Objective: To investigate the association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma (ESCC) in China. Methods: From March 2014 to September 2018, ESCC patients from three hospitals (the Affiliated Hospital of Medical College of Shantou University, Shantou Central Hospital in Southern Chaoshan area and First Affiliated Hospital of Zhengzhou University in Northern Taihang Mountain) were selected as a case group; non-esophageal patients who had a physical examination were selected as a control group. The case and control group were paired by age (±5 years) and a 1:1 ration. A total of 1 528 subjects were enrolled including 764 patients in the case group and 764 patients in the control group. About 3-5 ml venous blood samples were collected, and the erythrocyte glutathione reductase activity coefficient (GRAC) was measured to assess the whole blood riboflavin level. A multivariate conditional logistic regression model was used to analyze the association between the GRAC and the risk of ESCC. The association between the GRAC and the prognosis of ESCC was analyzed by using Cox proportional risk regression model based on 288 patients with complete survival data. They were divided into two groups, the high GRAC group (GRAC≥7.87) group and the low GRAC group (GRAC<7.87) according to the strongest correlation between the total survival time, survival outcome and GRAC (GRAC=7.87). Results: Among the 1 528 patients, 958 patients were from Southern Chaoshan area, including 479 patients in the case group with an average age about (59.90±9.34) years and 479 patients in the control group with an average age about (59.55±8.77) years. Other 570 patients were from Northern Taihang Mountain area, including 285 patients in the case group with an average age (58.39±5.19) years and 285 patients in the control group with an average age about (58.74±4.57) years. The multivariate conditional logistic regression showed that the OR (95 %CI ) of the GRAC and the risk of ESCC was 1.009 (0.998-1.019). The Cox proportional hazard regression model analysis showed that the HR (95 %CI ) of the high GRAC group was 1.712 (1.034-2.824) compared with the low GRAC group in the 50-70 years group. Conclusion: The whole blood riboflavin level might not be associated with the occurrence of ESCC. The high whole blood riboflavin level would be more beneficial to the prognosis of ESCC patients aged 50-70 years.

Objective: To investigate the in vitro and in vivo effects of apatinib in esophageal squamous cell carcinoma and the underlying mechanisms. Methods: The esophageal cancer cells, KYSE-150 and ECA-109, were divided into control group and apatinib treatment group at the concentrations of 2.5, 5, 10, 20 and 40 μmol/L respectively. All of experiments were performed in triplicate. MTT and colony formation assays were used to measure cell proliferation. Transwell assay was used to determine the migration capacity. The effect of apatinib on cell cycle and apoptosis was analyzed by flow cytometry. The expression of VEGF and VEGFR-2 was measured by real-time quantitative PCR (qRT-PCR). The concentration of VEGF in the cell supernatant was assessed by enzyme-linked immunosorbent assay (ELISA). The expression levels of MEK, ERK, p-MEK, p-ERK, JAK2, STAT3 and p-STAT3 after VEGF stimulation were detected by Western blot. Furthermore, the nude mice xenograft model was established. The tumor-bearing mice were randomly divided into control group, apatinib low dose treatment group (250 mg) and apatinib high dose treatment group (500 mg), respectively. Tumor inhibition rates of different groups were calculated. And then the expressions of VEGF and VEGFR2 were detected in xenograft tissues by immunohistochemical staining. Results: In the presence of 20 μmol/L and 40 μmol/L of apatinib for 24 hours, the migration cell numbers of KYSE-150 and ECA-109 were 428.67±4.16 and 286.67±1.53 as well as 1 123.67±70.00 and 477.33±26.84, respectively, that were significantly lower than control group ( P <0.05 for all). In addition, after treatment with 10 μmol/L, 20 μmol/L and 40 μmol/L of apatinib for 7 days on KYSE-150 and ECA-109, the colony formation rates were (65.12±25.48)%, (58.19±24.73)% and (29.10±22.40)% as well as (70.61±15.14)%, (61.12±17.21)% and (43.09±11.13)%, respectively. The colony formation rates of 20 μmol/L and 40 μmol/L of apatinib treatment groups were significantly lower than control group (100.00±0.00, P <0.05). The cell cycle ratio of G(2)/M phase and apoptosis rate of control group and 20 μmol/L apatinib group in KYSE-150 cells were (12.14±2.13)% and (3.49±0.74)% as well as (26.27±3.30)% and (15.65±1.54)%, respectively. The corresponding ratios in ECA-109 cells were (3.44±0.57)% and (6.31±1.43)% as well as (22.64±2.36)% and (49.26±1.62)%, respectively. The results show that apatinib suppressed cell cycle progression at G(2)/M phase and induced cell apoptosis in both KYSE-150 and ECA-109 cells ( P <0.05 for all). In the presence of 20 μmol/L and 40 μmol/L of apatinib in KYSE-150 cells, the relative levels of VEGF mRNA were (42.57±10.43)% and (25.69±1.24)%, and those of VEGF-2 mRNA were (36.09±10.82)% and (13.99±6.54)%, which were all significantly decreased compared to control group (100.00±0.00, P <0.05 for all). For ECA-109 cells, the relative expression of VEGF and VEGFR2 showed similar tendency ( P <0.05 for all). Moreover, after treatment with 20 μmol/L and 40 μmol/L of apatinib in KYSE-150 cells, the VEGF concentrations were (766.48±114.27) pg/ml and (497.40±102.18)pg/ml, which were significantly decreased compared to control group [(967.41±57.75) pg/ml, P <0.05)]. The results in ECA-109 were consistent ( P <0.05). Furthermore, after treatment with 40 μmol/L of apatinib in KYSE-150 and ECA-109, the relative expression of p-MEK and p-ERK were 0.49±0.05 and 0.28±0.03 as well as 0.63±0.03 and 1.22±0.15, which were significantly lower than control group (1.23±0.19 and 0.66±0.07 as well as 1.03±0.20 and 1.76±0.20; P <0.05). The relative expression of STAT3, p-STAT3 in control group and experimental group were 0.96±0.15 and 0.85±0.16 as well as 0.62±0.09 and 0.36±0.13, respectively. The results showed that the protein levels of STAT3 and p-STAT3 were significantly lower than the control group ( P <0.05 for all). The inhibition rates of apatinib in xenograft nude mice were 29.25% and 19.96% for 250 mg and 500 mg treatment groups. The concentration of VEGF were (25.11±4.12) pg/ml, (16.40±2.81) pg/ml and (15.04±4.88)pg/ml for control, 250 mg and 500 mg treatment groups, respectively. Conclusions: Apatinib can inhibit cell proliferation, induce apoptosis and suppress migration of esophageal cancer cells in vitro and in vivo . This effect was mainly mediated via the alterations of Ras/Raf/MEK/ERK pathway and JAK2/STAT3 pathway.

Objective: To investigate the expression of microRNA-133b (miR-133b) in esophageal squamous cell carcinoma (ESCC), and explore its effect and the underlying molecular mechanisms on cell proliferation and invasion. Methods: Real-time quantitative PCR (qPCR) was used to examine miR-133b expression in 63 ESCC tissues and paired adjacent non-cancerous tissues, several ESCC cells (Eca109, EC9706, EC1, TE1, KYSE70) and normal esophageal epithelial cell Het-1A. MiR-133b mimic, inhibitor and negative control (NC) were transfected into TE1 cells. The effect of miR-133b on cell proliferation and invasion were determined by CCK-8 and Transwell assays, respectively. Subsequently, the target gene of miR-133b was predicted by online tools TargetScan and miRDB, which was verified by dual luciferase reporter assays. Finally, Western blot was utilized to detect the effects of miR-133b overexpression on expression of target gene TAGLN2 as well as EMT-related proteins E-cadherin, N-cadherin, Snail, Slug and Vimentin. Results: Relative levels of miR-133b in ESCC tissues (0.295±0.040) were significantly lower than those in adjacent non-cancerous tissues (1.002±0.011, P <0.001). The expression of miR-133b was tightly associated with clinical staging, lymph node metastasis and prognosis. Moreover, relative levels of miR-133b in ESCC cells Eca109, EC9706, EC1, TE1 and KYSE70 (0.679±0.031, 0.391±0.008, 0.236±0.016, 0.031±0.005 and 0.099±0.020) were evidently lower than that in normal esophageal epithelial cell Het-1A (1.005±0.016, all P <0.001). In TE1 cells, miR-133b mimic significantly increased the level of miR-133b to 6.199±0.627, and suppressed cell proliferation and invasion, whereas miR-133b inhibitor obviously decreased its expression to 0.182±0.023, and promoted cell proliferation and invasion. Most notably, the relative luciferase activities of miR-133b-mimic group (0.320±0.018) in TE1 cells transfected with TAGLN-3'UTR-WT were markedly lower than that in NC group (1.010±0.036, P <0.001), whereas those in TAGLN-3'UTR-MUT transfection cells were 1.019±0.056 and 1.008±0.021, respectively, showing no significantly statistical difference ( P >0.05). Furthermore, miR-133b overexpression markedly downregulated TAGLN2, N-cadherin, Snail, Slug and Vimentin levels, and increased E-cadherin expression. Conclusion: MiR-133b plays an important role in the proliferation and invasion of ESCC cells by regulating TAGLN2 expression, and it may be a potential therapeutic target for ESCC patients.

Objective: To investigate PLOD2 expression in esophageal squamous cell carcinoma, and to explore the potential mechanism by which PLOD2 promotes tumor metastasis. Methods: The expression of PLOD2 in 60 cases of esophageal squamous cell carcinoma (the patients were collected at the first Affiliated Hospital of Xinxiang Medical University, from January 2016 to December 2017) was investigated by immunohistochemistry. Fibrillar collagen formation and collagen deposition were detected by picrosirius red staining. Correlation of PLOD2 expression with clinical pathologic features of the patients was performed using χ(2) test and Kaplan-Meier analysis. After EC-109 cells were transfected with LV-vector and LV-over/PLOD2, the expression of PLOD2 was detected by real time PCR and the impact of POLD2 on invasion in EC-109 cells was determined by transwell migration and invasion assays. The expression of PLOD2/AKT epithelial-to-mesenchymal transition signal pathway related proteins was detected by Western blot. Results: The expression level of PLOD2 in esophageal squamous cell carcinoma was 81.7% (49/60 cases),higher than their paired noncancerous tissues(8.3%, 5/60; P< 0.01), and correlated significantly with tumor depth of invasion and nodal metastasis ( P< 0.01). Picrosirius red staining showed that collagen deposition was increased and the degree of fibrillar organization was enhanced in carcinoma tissues that had higher PLOD2 expression. Transwell migration and invasion assays showed that PLOD2 significantly promoted the migration and invasion ability of EC-109 cells. Western blot showed that PLOD2 significantly increased the expression levels of p-FAK, p-AKT and vimentin in EC-109 cells. Conclusions: Esophageal squamous cell carcinoma has a high expression of PLOD2 that correlates with tumor invasion and lymph node metastasis. PLOD2 promotes invasion and metastasis of esophageal squamous cell carcinoma through epithelial-to-mesenchymal transition via FAK/AKT signal pathway.

Objective: To apply Nutritional Risk Screening-2002(NRS-2002) to perform nutritional status score for the patients with thoracic esophageal squamous cell carcinoma (ESCC) receiving surgery, and to explore the prognostic impact of long-term survival. Methods: A total of 117 patients who were diagnosed with ESCC from 2010 to 2012 were retrospectively analyzed. They recieved standard curative esophagectomy in the Yangzhou University Affiliated Taixing People's Hospital. The nutritional status and risk score for recruited patients were assessed according to the standard of NRS-2002 tool prior to surgery, and these patients were grouped for further analysis according to the median values of NRS-2002 score. Finally, the relationship between NRS-2002 score and prognosis was analyzed. Results: Patients were classified into two groups, with 45 in the NRS-2002<2.0 group, and 72 cases in the NRS-2002≥2.0, respectively. In the NRS-2002<2.0 group, the 1-, 3-, and 5-year progression-free survival (PFS) rates were 75.6%, 44.4% and 40.0% separately, while in the NRS-2002≥2.0 group, the PFS rates were 61.1%, 6.9% and 4.2% respectively, and the differences were statistically significant ( P <0.001). Correspondingly, in the NRS-2002< 2.0 group, the 1-, 3-, and 5-year overall survival (OS) rates were 97.8%, 66.7% and 57.8% separately, while in the NRS-2002≥2.0 group, the OS rates were 91.7%, 33.3% and 16.7% respectively, and the differences were also statistically significant ( P <0.001). Univariate analysis showed that N stage, TNM stage and NRS-2002 score were closely related to PFS and OS ( P <0.05), and T stage was only associated with OS in patients with thoracic esophageal squamous cell carcinoma ( P <0.05). Furthermore, multivariate Cox regression analysis showed that N stage ( RR =1.640, 95% CI 1.049-2.565, P =0.030) and NRS-2002 ( RR =3.154, 95% CI 1.946-5.113, P <0.001) were independent prognostic factors for PFS in patients with ESCC after surgery. Additionally, pathological differentiation ( RR =1.556, 95% CI 1.004-2.440, P =0.041), N stage ( RR =1.624, 95% CI 1.017-2.593, P =0.042) and NRS-2002 ( RR =3.906, 95% CI 2.245-6.795, P <0.001) were independent prognostic factors for OS in ESCC patients following surgery. Conclusion: Preoperative nutritional risk screening NRS-2002 score is an independent prognostic factor in patients with ESCC receiving surgery and could be used as a tool for primary screening for nutritional risk.

Objective: To evaluate the expression of cytokeratin (CK)7, CK8/18, CK19 and p40 in esophageal squamous cell carcinoma (ESCC) and its significances. Methods: One hundred and ninety cases of surgically resected ESCCs and 154 normal esophageal tissues as control were collected at the First Affiliated Hospital of Zhengzhou University in 2012.Of the 190 ESCC cases including 116 male and 74 female, aged 28-82 (60.3±8.6) years, 88 cases <60 years old and 102 cases ≥60 years old. Tissue sections were immunostained for CK7, CK8/18, CK19 and p40, and the expression was evaluated and correlated with the clinicopathologic findings and outcome. Results: CK19 and p40 were expressed in 190 cases of ESCCs; with 147 cases (77.4%) and 151 cases (79.5%) showing high p40 and CK19 expression, respectively; while 43 cases (22.6%) and 39 cases (20.5%) showed low p40 and CK19 expression, respectively. The low expression groups showed more lymph node metastases and higher pTNM stages compared to the high expression groups. The high CK19 expression group showed better prognosis than the low expression group ( P <0.01); p40 expression was not correlated with prognosis( P >0.05). In contrast, CK7 and CK8/18 expression was only seen in 29 cases (15.3%) and 59 cases (31.1%) of ESCCs, respectively, and their expression correlated significantly with the degree of tumor differentiation and lymph node metastasis ( P <0.05). The prognosis in the CK7 negative group was better than that in the CK7 positive group. Similar results were found in CK8/18 expression. Multivariate analysis revealed that pTNM stages, low CK19 expression and CK8/18 expression were independent prognostic factors. Conclusions: Low p40 expression and the expression of CK7 and CK8/18 cannot exclude poorly-differentiated ESCCs.CK7 and CK8/18 expression and low CK19 and p40 expression in the ESCCs are associated with lymph node metastasis and poor prognosis. Decreased expression of CK19 and positive expression of CK8/18 in ESCCs are independent prognostic markers.

Objective: To investigate the associated high risk factors of postoperative relapse and metastasis for patients with confined tumors (grade pT1b-4a) without lymph-node metastases (pN0) in thoracic esophageal squamous cell carcinoma (ESCC)., Methods: Clinicopathological and follow up data of ESCC patients undergoing radical surgical resection as primary treatment in the Department of Thoracic Surgery, Shanghai Chest Hospital between January 2004 and December 2012 from Hospital Database were retrospectively collected. The inclusion criteria were as follows: (1) the first development of ESCC confirmed by histopathology without lymphatic and distant metastasis; (2) pathological stage of pT1bN0M0 to pT4aN0M0 according to the Union for International Cancer Control (UICC) in 2009; (3) curative trans-thoracic esophagectomy with R0 (tumor-free surgical margin) resection, using the Ivor-Lewis or McKeown procedure; two-field lymphadenectomy or three-field lymph node dissection based on the positive results of preoperative cervical ultrasonography examination or CT scan; (4) without adjuvant chemotherapy and/or radiotherapy before and after operation; (5) complete follow-up data. Logistic regression analysis was employed to identify the clinicopathological factors affecting the postoperative relapse and metastasis., Results: A total of 112 patients were eligible, including 94 male cases and 18 female cases; age of (58.6±7.7) years; squamous carcinoma of upper thorax in 25 cases, of middle thorax in 67 cases and of lower thorax segment in 20 cases; 12 cases of high-differentiated ESCC, 49 cases of moderate-differentiated ESCC, poorly-differentiated ESCC in 48 cases; 4 cases of I(a stage, 9 cases of I(b, 24 cases of II(a, 62 cases of II(b, 13 cases of III(a; the tumor length >4 cm in 43 cases, ≤4 cm in 69 cases. Forty-three (38.4%) patients presented relapse or metastasis during the follow-up, including 24 (21.4%) of loco-regional relapse, 13 (11.6%) of distant metastasis, and 6(5.4%) of both above. Multivariate regression analysis revealed that poorly-differentiated tumor (OR=1.899, 95%CI:1.233-2.925, P=0.004), upper-middle location (OR=2.351, 95%CI:1.188-4.653, P=0.014), and tumor length >4 cm (OR=2.381, 95%CI:1.009-5.618, P=0.048) were independent risk factors of overall postoperative relapse and metastasis for thoracic ESCC with stage pT1b N0M0-T4aN0M0. Further stratified analysis identified that only poorly-differentiated tumor (OR=1.730, 95%CI:1.121-2.671, P=0.013) was an independent risk factor of loco-regional relapse, whereas pathological stage II(b-III(a (OR=3.372, 95%CI:1.206-9.428, P=0.021) was an independent risk factor of distant metastasis., Conclusions: Poorly-differentiated tumor, tumor length >4 cm, and upper-middle location may be regarded as high risk factors for predicting overall relapse and metastasis of pN0 thoracic ESCC patients after esophagectomy. Moreover, poorly-differentiated tumor is the only independent risk factor of postoperative loco-regional relapse, meanwhile it should be noted that pathological stage II(b-III(a is closely related to postoperative distant metastasis.

Objective: To investigate the relationship of heterogeneity of esophageal squamous cell carcinoma (ESCC) and chemotherapy sensitivity. Methods: Five different region specimens isolated from primary tumor(R1~R5)and 1 specimen(R6)isolated from adjacent non-neoplastic tissue from 10 ESCC patients who underwent surgical treatment were cultured in vitro. The inhibitory effect of cisplatin on proliferation of ESCC cells from different regions was determined by methyl thiazolyl tetrazolium (MTT). The cell cycle and apoptosis induced by cisplatin was determined by flow cytometry (FCM) analysis. The mRNA levels of ATP7A and ATP7B were determined by quantitive RT-PCR (qRT-PCR). Results: The result showed that different regions of each specimen exhibited different chemotherapy sensitivity to cisplatin, and the cell survival rates of region R6 of each specimen were higher than other regions from the same specimen. The cell survival rate of region R3 from the tenth specimen was (81.42±8.84)%, which is significantly higher than (11.90±2.75)% of region R5 ( P <0.01). FCM analysis showed that significant differences of early apoptosis and later apoptosis were observed in six specimens induced by cisplatin ( P <0.05), and significant differences of cell cycle and G(1) period were observed in seven specimens ( P <0.05). The qRT-PCR results showed that the mRNA level of ATP7A in region R1, R2, R3, R4 and R5 was (100.00±3.42)%, (118.10±2.21)%, (75.40±4.15)%, (95.40±3.32)% and (41.70±2.57)%, respectively, with significant differences ( P <0.05). The mRNA level of ATP7A in region R6 was (175.20±5.32)%, significantly higher than those of regions from R1 to R5 ( P <0.05). The mRNA level of ATP7B in region R1, R2, R3, R4 and R5 was (100.00±4.89)%, (73.60±2.65)%, (175.60±6.12)%, (46.10±4.62)% and (363.70±8.67)%, respectively, with significant differences ( P <0.05). The mRNA level of ATP7B in region R6 was (1 165.40±7.25)%, significantly higher than those of regions from R1 to R5 ( P <0.05). Conclusion: The intratumor heterogeneity of ESCC results in the heterogeneity of resistance to cisplatin, which affects the chemotherapeutic effect.