Outcomes of surgical treatment for enterovesical fistula in Crohn's disease.

Enterovesical fistula (EVF) in Crohn's disease (CD) often does not improve with medical treatment and requires surgical treatment. The surgical treatment strategy for EVF in CD is definitive resection of the intestinal tract side, and performing a leak test using dye injection into the bladder after EVF dissection to determine the appropriate surgical procedure for the bladder side. This study aimed to evaluate the outcomes of surgical treatment for EVF in CD. Twenty-one patients who underwent surgery for EVF between 2006 and 2021 were included and retrospectively evaluated for clinical background, surgical procedures, and postoperative complications. The most common origin of EVF was the ileum (17 cases; 81%), and the most common site of EVF formation was the apex (12; 57%). Surgical approaches were laparotomy in 11 (52%) cases and laparoscopy in 10 (48%). Surgical procedures on the bladder side were fistula dissection in 13 (62%) cases and sutured closure of fistula in 8 (38%). A comparison of approaches revealed no significant difference in operative time, but the amount of blood loss was significantly less in the laparoscopy (p < 0.01). There was no significant difference in the occurrence of postoperative complications between approaches. Postoperative anti-TNF-α antibody agents were used in 17 (81%) cases, and there were no cases of recurrent EVF. In conclusion, definitive resection of the intestinal tract and minimal treatment on the bladder side were sufficient to achieve satisfactory outcomes for EVF in CD.

The long-term quality of life after distal and pylorus-preserving gastrectomy for stage I gastric cancer: A prospective multi-institutional study (CCOG1601).

PURPOSE: While regarded as function-preserving gastrectomy, few prospective longitudinal clinical trials have addressed the postoperative quality of life (QOL) after pylorus-preserving gastrectomy (PPG). We prospectively compared chronological changes in postoperative body weight and the QOL between PPG and distal gastrectomy (DG) for pathological Stage I gastric cancer (GC). METHODS: We conducted a multi-institutional prospective study (CCOG1601) to evaluate patients who underwent DG and PPG. The QOL was examined using the European Organization for Research and Treatment of Cancer Quality of life questionnaire-C30 (EORTC QLQ-C30) and the Post-Gastrectomy Syndrome Assessment Scale-37 (PGSAS-37). A total of 295 patients were enrolled from 15 institutions, and propensity score matching was performed to adjust for the essential variables for comparison analyses. RESULTS: After propensity score matching, 25 pairs of patients were identified. In the first postoperative month, DG achieved a superior nausea and vomiting score (EORTC QLQ-C30) and meal-related distress, indigestion, and dumping scores (PGSAS-37). No significant differences were noted between DG and PPG in the long-term QOL. Postoperative body weight loss was similar in both groups. CONCLUSIONS: This prospective observational study failed to demonstrate the superiority of PPG over DG in terms of postoperative body weight changes and the QOL.

Therapeutic Potential of Antibody Targeting Neuronal Pentraxin Receptor in Esophageal Squamous Cell Carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) has a poor prognosis despite advances in multidisciplinary treatments and immune checkpoint inhibitors. We previously reported that neural pentraxin receptor (NPTXR), a transmembrane protein mainly expressed in the brain and involved in synaptic transmission, is implicated in gastric cancer malignancy. This study evaluated the expression and function of NPTXR in ESCC, the therapeutic potential of monoclonal antibody (mAb) against NPTXR, and its prognostic value in ESCC patients. METHODS: The study involved analyzing the NPTXR expression in 21 ESCC cell lines and total 371 primary ESCC tissue samples using quantitative reverse-transcription polymerase chain reaction and immunohistochemistry. The impact of NPTXR on the malignant behavior of ESCC was examined using small interfering RNA-mediated knockdown and a subsequent assessment of cell proliferation, apoptosis, and adhesion. This study further investigated the efficacy of anti-NPTXR mAb in vitro and associations between the expression of NPTXR messenger RNA (mRNA) and protein with clinicopathological factors and the prognosis. RESULTS: NPTXR was overexpressed in several ESCC cell lines and primary ESCC tissues. Knockdown of NPTXR in ESCC cells resulted in reduced proliferation, increased apoptosis, and decreased cell adhesion. The mAb against NPTXR significantly inhibited ESCC cell proliferation in vitro. A high NPTXR expression in patient tissues was correlated with a worse overall survival, suggesting its potential as a prognostic biomarker. CONCLUSIONS: NPTXR influences the malignant behavior of ESCC cells. Anti-NPTXR mAb may be a promising therapeutic agent, and its expression in ESCC tissues may serve as a prognostic biomarker.

Prognostic Impact of CDKN2A Mutations Associated With Smoking and Drinking History in Japanese Digestive Cancers.

BACKGROUND/AIM: Organs of the digestive system are frequent sites of cancer development, and digestive tract cancers are the leading causes of death worldwide, including in Japan. Most of these cancers are associated with smoking or drinking habits. This study focused on the clinical and genomic characteristics of patients with these cancers using the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database, which comprises a large volume of data on Japanese patients who have undergone tumor profiling gene panel tests. PATIENTS AND METHODS: The genomic and clinical data from patients with digestive tract cancers registered in C-CAT between 2019 and 2023 were retrospectively reviewed. The data were derived from 412 patients with esophageal squamous cell carcinoma, 558 with gastric adenocarcinoma, 3,368 with colorectal adenocarcinoma, 139 with hepatocellular carcinoma, 2,050 with cholangiocarcinoma, and 2,552 with pancreatic ductal adenocarcinoma. RESULTS: CDKN2A, CDKN2B, and MTAP mutations were associated with both smoking and drinking history, and patients with these mutations had a worse prognosis. Almost all gene alterations in CDKN2B and MTAP were deletions, often accompanied by CDKN2A deletion. CDKN2A mutation emerged as the most decisive prognostic factor among these mutations. Although CDKN2A mutations were frequently seen in esophageal squamous cell carcinoma, cholangiocarcinoma, and pancreatic ductal adenocarcinoma, statistically significant differences in survival outcomes were only identified in the latter two. CONCLUSION: CDKN2A mutations were associated with smoking and drinking in digestive cancers. This mutation was prevalent among patients with cholangiocarcinoma and pancreatic ductal adenocarcinoma, for whom they could serve as prognostic factors.

Protocol of a phase II study investigating the efficacy and safety of trifluridine/tipiracil plus ramucirumab as a third-line or later treatment for advanced gastric cancer.

In Japan, systemic chemotherapy is the standard treatment for unresectable, advanced, or recurrent gastric cancer. However, numerous patients with gastric cancer do not receive late-line treatment because of the rapid progression of gastric cancer. Additionally, late-line treatments, such as nivolumab, trifluridine tipiracil (FTD/TPI), or irinotecan, have limited effects on improving clinical symptoms and delaying the onset of symptoms associated with cancer progression. Recently, a combination of FTD/TPI and ramucirumab was reported to have a high response rate in late-line treatment; however, owing to patient selection bias and a high rate of hematologic toxicity in that previous study, this regimen may not be feasible in real-world clinical applications. Our objective is to conduct a single-arm phase II study to assess the safety and efficacy of FTD/TPI plus ramucirumab combination therapy for gastric cancer after third-line treatment under real-world clinical conditions. This study will recruit 32 patients according to eligibility criteria and administer FTD/TPI (35 mg/m2) and intravenous ramucirumab (8 mg/kg). The primary endpoint will be the time to treatment failure. The secondary endpoints will include the overall survival time, progression-free survival time, overall response rate, disease control rate, relative dose intensity, and incidence of adverse events. The results will add new insights for improving the late-line treatment of advanced gastric cancer.

Risk Factors for Long-term Body Weight Loss After Proximal Gastrectomy: A Retrospective Analysis.

BACKGROUND/AIM: Proximal gastrectomy (PG) is a therapy for early-stage proximal gastric cancer and offers advantages such as the preservation of food storage capacity and less body weight loss (BWL). Nevertheless, significant BWL following PG may occur, affecting the patient's well-being and survival. In this study, we aimed to identify the relevant factors for BWL following PG by analyzing an institutional database of patients. PATIENTS AND METHODS: We enrolled 58 consecutive patients who underwent PG for gastric or esophagogastric junction cancer at our institution between April 2004 and March 2021. Based on BWL at 12 months postoperatively, we retrospectively compared and examined patient characteristics, surgical details, and nutritional markers. RESULTS: The mean BWL of the 58 patients included in this analysis was 14.0±7.2%. When the patients were divided into BWL-moderate (n=29) and BWL-severe (n=29) groups using a cutoff value of 15.7%, the latter experienced early BWL within 1 month postoperatively, primarily due to body fat mass reduction, with no recovery during the 60 months of follow up. In contrast, gradual recovery was observed among patients in the BWL-moderate group after experiencing the lowest body weight 24 months postoperatively. A greater decrease in body fat mass than in muscle mass was observed in both groups. Blood hemoglobin levels did not recover in the BWL-severe group. CONCLUSION: The BWL-severe group after proximal gastrectomy demonstrated significantly greater early postoperative BWL, primarily attributed to a reduction in body fat mass, with hardly any recovery. Early postoperative nutritional intervention might be proposed to prevent long-term BWL.

A multi-institutional prospective observational study to compare postoperative quality of life of patients who undergo total or proximal gastrectomy for early gastric cancer (CCOG1602).

BACKGROUND: Proximal gastrectomy (PG) has become an increasingly preferred procedure for treating early cancer in the upper third of the stomach. However, advantages of PG in postoperative quality of life (QOL) over total gastrectomy (TG) has not fully proven. METHODS: We conducted a multi-institutional prospective observational study (CCOG1602) of patients who undergo TG or PG for cStage I gastric cancer. We used the PGSAS-37 and EORTC-QLQ-C30 to evaluate the changes in body weight and QOL over a 3-year postoperative period. The primary endpoint was the weight loss rate 3 years after surgery. RESULTS: We enrolled 109 patients from 18 institutions and selected 65 and 19 patients for inclusion in the TG and PG groups, respectively. Mean postoperative weight loss rates were 16.0% and 11.7% for the TG and PG groups, respectively (p = 0.056, Cohen's d 0.656) during postoperative year 1% and 15.0% and 10.8% for TG and PG (p = 0.068, Cohen's d 0.543), respectively, during postoperative year 3, indicating that the PG group achieved a better trend with a moderate effect size. According to the PGSAS-37, the PG group experienced a better trend in the indigestion subscale (p < 0.001, Cohen's d -1.085) and total symptom score (p = 0.050, Cohen's d -0.59) during postoperative year 3 compared with the TG group. In contrast, the EORTC-QLQ-C30 detected no difference between the groups at any time point during 3-year postoperative period. CONCLUSIONS: This prospective study demonstrates that PG tended to be more favorable compared with TG with respect to postoperative weight loss and QOL, particularly regarding indigestion.

Killer cell lectin-like receptor G2 facilitates aggressive phenotypes of gastric cancer cells via dual activation of the ERK1/2 and JAK/STAT pathways.

BACKGROUND: Advanced gastric cancer (GC) has a poor prognosis. This study aimed to identify novel GC-related genes as potential therapeutic targets. METHODS: Killer cell lectin-like receptor G2 (KLRG2) was identified as a candidate gene by transcriptome analysis of metastatic GC tissues. Small interfering RNA-mediated KLRG2 knockdown in human GC cell lines was used to investigate KLRG2 involvement in signaling pathways and functional behaviors in vitro and in vivo. Clinicopathological data were analyzed in patients stratified according to tumor KLRG2 mRNA expression. RESULTS: KLRG2 knockdown in GC cells decreased cell proliferation, migration, and invasion; caused cell cycle arrest in G2/M phase; induced apoptosis via caspase activation; suppressed JAK/STAT and MAPK-ERK1/2 pathway activities; and upregulated p53 and p38 MAPK activities. In mouse xenograft models of peritoneal metastasis, the number and weight of disseminated GC nodules were decreased by KLRG2 knockdown. High tumor levels of KLRG2 mRNA were significantly associated with lower 5-year overall survival (OS) and relapse-free survival (RFS) rates in patients with Stage I-III GC (5-year OS rate: 64.4% vs. 80.0%, P = 0.009; 5-year RFS rate: 62.8% vs. 78.1%, P = 0.030). CONCLUSIONS: KLRG2 knockdown attenuated the malignant phenotypes of GC cells via downregulation of JAK/STAT and MAPK-ERK1/2 pathway activity and upregulation of p38 MAPK and p53. Targeted suppression of KLRG2 may serve as a new treatment approach for GC.

Docetaxel, cisplatin, and fluorouracil with pegfilgrastim on day 3 as neoadjuvant chemotherapy for esophageal cancer.

PURPOSE: A high risk of febrile neutropenia (FN) from neoadjuvant chemotherapy with docetaxel, cisplatin, and fluorouracil (DCF) for esophageal cancer has been reported. The optimal timing of prophylactic use of pegfilgrastim remains to be elucidated. To evaluate the effect of pegfilgrastim administered on day 3, we conducted a feasibility study. METHODS: Chemotherapy consisted of intravenous administration of docetaxel (70 mg/m2 per day) and cisplatin (70 mg/m2 per day) on day 1 and continuous infusion of 5-fluorouracil (750 mg/m2 per day) on days 1-5. Pegfilgrastim was given as a single subcutaneous injection at a dose of 3.6 mg on day 3 during each treatment course. This regimen was repeated every 3 weeks for up to a maximum of three courses. Prophylactic antibiotics were not needed but were allowed to be given at the discretion of the physician. The primary endpoint was the incidence of FN. RESULTS: Twenty-six patients were administered DCF in combination with pegfilgrastim on day 3. After the first course of DCF, 10 out of 26 patients (38.5%) experienced grade 4 neutropenia, and two patients (7.7%) experienced FN. Of the 14 patients who did not receive prophylactic antibiotics, four had grade 4 neutropenia, including two who developed FN. On the contrary, of the 12 patients who received prophylactic levofloxacin, six had grade 4 neutropenia, but no cases of FN were observed. CONCLUSION: Administration of pegfilgrastim on day 3 was not sufficient to prevent FN due to DCF treatment, and prophylactic administration of both pegfilgrastim and antibiotics could be a solution.

Exacerbated prognostic impact of multiple intramural metastasis versus single intramural metastasis of thoracic esophageal squamous cell carcinoma: evidence from an Uzbekistan cohort.

PURPOSE: Intramural metastasis (IM) is a poor prognostic factor for patients with esophageal squamous cell carcinoma (ESCC). We conducted this study to assess the prognostic impact of IM in an Uzbekistan cohort and to identify the factors associated with the poor prognosis of patients with ESCC and IM. METHODS: The subjects of this retrospective analysis were 1083 patients with thoracic ESCC, who underwent curative esophagectomy between 2001 and 2021 at the National Cancer Center of Uzbekistan. We compared the clinicopathological characteristics and survival outcomes of patients with versus those without IM and evaluated the factors associated with the poor prognosis of patients with IM. RESULTS: Patients with pathological IM (n = 59, 5.4%) were significantly older, had a higher percentage of lymphatic invasion and worse pathological N stage, and had shorter overall survival (OS) than patients without IM. Multivariable analysis of OS identified multiple IMs as the only independent prognostic factor in patients with IM (hazard ratio, 6.04; 95% confidence interval, 2.77-13.18; P < 0.001). Patients with multiple IMs had shorter OS and recurrence-free survival than those with a single IM. CONCLUSION: IM was a poor prognostic factor for patients with ESCC in this Uzbekistan cohort and multiple IMs were associated with worse outcomes.

Absence of Hypercoagulation Status after Neoadjuvant Treatment is Associated with Favorable Prognosis in Patients Undergoing Subtotal Esophagectomy for Esophageal Squamous Cell Carcinoma.

BACKGROUND: Abnormal activation of the coagulation system is associated with malignant tumor progression. Although neoadjuvant treatment (NAT) for resectable esophageal squamous cell carcinoma (ESCC) is the standard of care, the correlation between coagulation status and prognosis of patients undergoing preoperative treatment is insufficiently understood. METHODS: Patients (n = 200) who underwent radical subtotal esophagectomy after preoperative treatment for ESCC between January 2012 and December 2021were included in the analysis. Plasma D-dimer and fibrinogen levels and their combined indices (non-hypercoagulation; D-dimer and fibrinogen levels within the upper normal limit, or hypercoagulation; D-dimer or fibrinogen levels above the upper normal limit) were determined before and after NAT and correlated to clinicopathological factors and prognosis. RESULTS: The nonhypercoagulation group achieved superior overall survival (OS) than the hypercoagulation group (5-year OS rates = 89% vs. 55%; hazard ratio 3.62, P = 0.0008) when determined according to coagulation status after NAT. Multivariate analysis showed that hypercoagulation after NAT served as an independent factor for poor postoperative OS (hazard ratio 3.20; P = 0.0028). The nonhypercoagulation group achieved significantly better disease-free survival (76% vs. 54%; P = 0.0065) than the hypercoagulation group that experienced a significantly higher rate of hematogenous metastasis as an initial recurrence (P = 0.0337). CONCLUSIONS: Hypercoagulation state after NAT served as a valid indicator correlating with postoperative outcomes of patients with ESCC who underwent NAT followed by radical subtotal esophagectomy.

Genetic polymorphisms as predictive biomarkers of adverse events during preoperative chemotherapy in esophageal cancer.

PURPOSE: This study aimed to explore associations between genetic polymorphisms and adverse effects due to preoperative chemotherapy with docetaxel, cisplatin, and fluorouracil (DCF) for esophageal cancer. METHODS: Preoperative DCF (docetaxel, 70 mg/m2/day, day 1; cisplatin, 70 mg/m2/day, day 1; fluorouracil, 750 mg/m2/day, days 1-5) was repeated every 3 weeks for up to three cycles. Genotyping of nine candidate genetic polymorphisms was conducted using blood samples from the enrolled patients. RESULTS: According to a multivariable analysis evaluating 50 patients, grade 3 or worse neutropenia was more likely to occur in those with the ABCC2-24C/T or T/T genotype (rs717620) (OR, 5.30, P = 0.013). Additionally, patients with the TYMS 3'-UTR 0 bp/0 bp genotype (rs151264360) showed a trend toward grade 3 or worse hyponatremia (OR, 0.16, P = 0.005). Grade 2 or worse thrombocytopenia was more likely to occur in patients with the TNF-α-1031C/T or T/T genotype (rs1799964) (OR, 6.30, P = 0.016) and IL-6-634C/C genotype (rs1800796) (OR, 0.18, P = 0.034), and grade 2 or worse anemia was more likely to occur in patients with the MCP-1-2518G/G genotype (rs1024611) (OR, 0.19, P = 0.027). CONCLUSIONS: ABCC2-24C > T (rs717620), TYMS 3'-UTR 6-bp indel (rs151264360), TNF-α-1031T > C (rs1799964) as well as IL-6-634G > C (rs1800796), and MCP-1-2518A > G (rs1024611) polymorphisms might serve as independent and predictive biomarkers for neutropenia, hyponatremia, thrombocytopenia, and anemia, respectively, during preoperative chemotherapy with docetaxel, cisplatin, and fluorouracil for patients with esophageal cancer.

Therapeutic antibody targeting natriuretic peptide receptor 1 inhibits gastric cancer growth via BCL-2-mediated intrinsic apoptosis.

Despite recent advances in the development of therapeutic antibodies, the prognosis of unresectable or metastatic gastric cancer (GC) remains poor. Here, we searched for genes involved in the malignant phenotype of GC and investigated the potential of one candidate gene to serve as a novel therapeutic target. Analysis of transcriptome datasets of GC identified natriuretic peptide receptor 1 (NPR1), a plasma membrane protein, as a potential target. We employed a panel of human GC cell lines and gene-specific small interfering RNA-mediated NPR1 silencing to investigate the roles of NPR1 in malignancy-associated functions and intracellular signaling pathways. We generated an anti-NPR1 polyclonal antibody and examined its efficacy in a mouse xenograft model of GC peritoneal dissemination. Associations between NPR1 expression in GC tissue and clinicopathological factors were also evaluated. NPR1 mRNA was significantly upregulated in several GC cell lines compared with normal epithelial cells. NPR1 silencing attenuated GC cell proliferation, invasion, and migration, and additionally induced the intrinsic apoptosis pathway associated with mitochondrial dysfunction and caspase activation via downregulation of BCL-2. Administration of anti-NPR1 antibody significantly reduced the number and volume of GC peritoneal tumors in xenografted mice. High expression of NPR1 mRNA in clinical GC specimens was associated with a significantly higher rate of postoperative recurrence and poorer prognosis. NPR1 regulates the intrinsic apoptosis pathway and plays an important role in promoting the GC malignant phenotype. Inhibition of NPR1 with antibodies may have potential as a novel therapeutic modality for unresectable or metastatic GC.

Low Expectancy of Conversion Surgery with R0 Resection in Patients with CEA > 5.0 ng/mL at the Initial RECIST Evaluation for Metastatic Gastric Cancer.

This retrospective study examined early the predictive factors for successful conversion surgery (CS) with R0 resection in patients with metastatic gastric cancer (MGC) who underwent systemic chemotherapy. This study included 204 patients diagnosed with metastatic gastric adenocarcinoma, who received chemotherapy between 2009 and 2019. Of these patients, 31 (15%) underwent CS with R0 resection. The incidence of CS with R0 resection was not affected by the volume of metastatic lesions or the presence of peritoneal metastasis. The overall survival time of the CS with R0 resection group was significantly longer than that of the non-CS group (hazard ratio, 0.12; 95% confidence interval, 0.07-0.23; p < 0.0001), with a 5 year overall survival rate of 50.2%. Multivariate analysis of 150 patients, excluding those with disease progression until the initial Response Evaluation Criteria in Solid Tumors (RECIST) evaluation, showed that carcinoembryonic antigen > 5.0 ng/mL at the initial RECIST evaluation was an independent, significant, and unfavorable predictor of CS with R0 resection (odds ratio, 0.21; p = 0.0108), whereas systemic chemotherapy with trastuzumab for HER2-positive cancer was a favorable factor (odds ratio, 4.20; p = 0.0119). Monitoring serum carcinoembryonic antigen levels during chemotherapy may be a useful predictor of the CS implementation in patients with MGC.

Mobilization of Circulating Tumor Cells after Short- and Long-Term FOLFIRINOX and GEM/nab-PTX Chemotherapy in Xenograft Mouse Models of Human Pancreatic Cancer.

Mobilization of CTCs after various types of therapy, such as radiation therapy, has been reported, but systematic study of CTCs after chemotherapy remained quite limited. In this study, we sequentially examined CTC numbers after single-dose and repetitive-dose chemotherapy, including FORFIRINOX (FFX) and Gemcitabine and nab-Paclitaxel (GnP) using two pancreatic cancer xenograft models. CTC was detected by the immunocytology-based microfluidic platform. We further examined the dynamic change in the histology of primary tumor tissues during chemotherapy. We confirmed a transient increase in CTCs 1-2 weeks after single-dose and repetitive-dose of FFX/GnP chemotherapy. Histological examination of the primary tumors revealed that the peak period of CTC at 1-2 weeks after chemotherapy corresponded to the maximal destructive phase consisting of cell cycle arrest, apoptosis of tumor cells, and blood vessel destruction without secondary reparative tissue reactions and regeneration of tumor cells. These findings indicate that mobilization of CTCs early after chemotherapy is mediated by the shedding of degenerated tumor cells into the disrupted blood vessels driven by the pure destructive histological changes in primary tumor tissues. These results suggest that sequential CTC monitoring during chemotherapy can be a useful liquid biopsy diagnostic tool to predict tumor chemosensitivity and resistance in preclinical and clinical settings.

Increased STX3 transcript and protein levels were associated with poor prognosis in two independent cohorts of esophageal squamous cell carcinoma patients.

BACKGROUND: Some conventional prognostic biomarkers for esophageal squamous cell carcinoma (ESCC) have the disadvantage that they have only been investigated at the level of either mRNA or protein levels or only in individual cohorts. Associations between Syntaxin 3 (STX3) expression and malignancy have been reported in several tumor types but not in ESCC. Here, we investigated the levels of both STX3 mRNA and protein, and its prognostic potential in two independent cohorts of patients with ESCC. METHODS: STX3 mRNA levels were examined in surgical specimens by quantitative PCR in a cohort that included 176 ESCC patients. STX3 protein levels were investigated in surgically resected ESCC tissues by immunohistochemistry using tissue microarrays in a different cohort of 177 ESCC patients. Correlations were analyzed between the expression of STX3 mRNA and protein with clinicopathological factors and long-term prognosis. RESULTS: Quantitative PCR indicated a significant association between high level of STX3 mRNA expression and lymph node involvement, pathological stage, and poor overall survival. The multivariate analysis demonstrated that high STX3 mRNA expression was independently associated with poor overall survival outcomes. Immunohistochemistry revealed that STX3 protein expression in ESCC tissues and high STX3 protein expression were also significantly correlated with unfavorable overall survival. CONCLUSIONS: Overexpression of STX3 mRNA and protein may serve as potential prognostic biomarkers for ESCC patients.

Risk Stratification by Tissue GAD1 Expression Level in Curatively Resected Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: To improve patient management, new biomarkers are required that stratify prognosis. Here we focused on glutamic acid decarboxylase 1 (GAD1), which is associated with proliferation of lung cancer cells, and investigated its expression and function in esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: We evaluated changes in the proliferative potential of ESCC cell lines using small interfering RNA-mediated GAD1 knockdown techniques. We analyzed GAD1 protein expression using a tissue microarray (TMA) and measured GAD1 mRNA expression to evaluate correlations between the expression level of each tissue and postoperative outcomes of two independent cohorts (the TMA and mRNA cohorts) of patients who underwent radical esophagectomy. RESULTS: GAD1 knockdown reduced cell proliferation. In the TMA cohort, high GAD1 expression significantly correlated with lymph node metastasis and advanced stage. Disease-free survival was significantly shorter in the group with high GAD1 expression, as was overall survival. Multivariate analysis of overall survival showed that positivity for GAD1 was an independent prognostic factor for poor survival. In the mRNA cohort, GAD1 mRNA expression in ESCC tissues was significantly up-regulated compared with that in adjacent noncancerous mucosal tissues. When patients were divided into high- and low-expression groups according to the median GAD1 mRNA expression level in ESCC tissues, overall survival was significantly shortened in the high GAD1 expression group. The incidence of initial hematogenous recurrence was significantly higher in the group with high GAD1 expression. CONCLUSION: GAD1 expression mediates the proliferative potential of ESCC cells, and a high level may serve as a useful prognostic biomarker for patients with ESCC.