Evaluating prognostic value and stage migration effects using a positive lymph node ratio in adenocarcinoma of the esophagogastric junction.

BACKGROUND: Adenocarcinoma of the esophagogastric junction (AEG) is increasing worldwide. Lymph node metastasis is an important clinical issue in AEG patients. This study investigated the usefulness of a positive lymph node ratio (PLNR) to stratify prognosis and evaluate stage migration. METHODS: We retrospectively analysed 117 consecutive AEG patients (Siewert type I or II) who received a lymphadenectomy between 2000 and 2016. RESULTS: A PLNR cut-off value of 0.1 most effectively stratified patient prognosis into two groups (P < 0.001). Also, prognosis could be clearly stratified into four groups: PLNR = 0, 0 < PLNR < 0.1, 0.1 ≤ PLNR < 0.2, and 0.2 ≤ PLNR (P < 0.001, 5-year survival rates (88.6%, 61.1%, 34.3%, 10.7%)). A PLNR ≥ 0.1 significantly correlated with tumour diameter ≥ 4 cm (P < 0.001), tumour depth (P < 0.001), greater pathological N-status (P < 0.001), greater pathological Stage (P < 0.001), and oesophageal invasion length ≥ 2 cm (P = 0.002). A PLNR ≥ 0.1 was a poor independent prognostic factor (hazard ratio 6.47, P < 0.001). The PLNR could stratify prognosis if at least 11 lymph nodes were retrieved. A 0.2 PLNR cut-off value discriminated a stage migration effect in pN3 and pStage IV (P = 0.041, P = 0.015) patients; PLNR ≥ 0.2 might potentially diagnose a worse prognosis and need meticulous follow-up post-surgery. CONCLUSION: Using PLNR, we can evaluate the prognosis and detect higher malignant cases who need meticulous treatments and follow-up in the same pStage.

Postoperative liver dysfunction is associated with poor long-term outcomes in patients with colorectal cancer: a retrospective cohort study.

BACKGROUND: Postoperative hepatobiliary enzyme abnormalities often present as postoperative liver dysfunction in patients with colorectal cancer. This study aimed to clarify the risk factors of postoperative liver dysfunction and its prognostic impact following colorectal cancer surgery. METHODS: We retrospectively analyzed data from 360 consecutive patients who underwent radical resection for Stage I-IV colorectal cancer between 2015 and 2019. A subset of 249 patients with Stage III colorectal cancer were examined to assess the prognostic impact of liver dysfunction. RESULTS: Forty-eight (13.3%) colorectal cancer patients (Stages I-IV) developed postoperative liver dysfunction (Common Terminology Criteria for Adverse Events version 5.0 CTCAE v5.0 ≥ Grade 2). Univariate and multivariate analyses identified the liver-to-spleen ratio on preoperative plain computed tomography (L/S ratio; P = 0.002, Odds ratio 2.66) as an independent risk factor for liver dysfunction. Patients with postoperative liver dysfunction showed significantly poorer disease-free survival than patients without liver dysfunction (P < 0.001). Univariate and multivariate analyses using Cox's proportional hazards model revealed that postoperative liver dysfunction independently was a poor prognostic factor (P = 0.001, Hazard ratio 2.75, 95% CI: 1.54-4.73). CONCLUSIONS: Postoperative liver dysfunction was associated with poor long-term outcomes in patients with Stage III colorectal cancer. A low liver-to-spleen ratio on preoperative plain computed tomography images was an independent risk factor of postoperative liver dysfunction.

Impact of the preoperative clinical N stage on the prognosis of patients with colon cancer.

AIM: Although preoperative clinical staging (cStage) is performed for most cancer patients, limited information is currently available on the relationship with postoperative prognosis. We herein investigated the relationship between cStage and prognosis of colon cancer (CC) patients, particularly focusing on the presence or absence of clinical lymph node (LN) metastasis. METHOD: This was a retrospective study on 840 consecutive patients with colon adenocarcinoma who underwent radical resection at our institution between January 2007 and December 2018. A Kaplan-Meier curve was used to analyse the prognosis of two groups: cN(+)pN(-); a group preoperatively diagnosed with clinical LN metastasis positive, but with no pathological LN metastasis postoperatively, and cN(-)pN(-); a group without clinical and pathological LN metastasis. We also investigated whether a clinical diagnosis is a more accurate prognostic factor than other clinical factors. RESULTS: Among pN(-) cases, the 5-year recurrence-free survival rate was significantly lower in preoperatively diagnosed cN(+) cases than in cN(-) cases (79.4% vs. 95.6%, 3.04 years vs. 3.85 years, p < 0.01). In a multivariate analysis of various preoperative clinical factors in pStage II cases, including high risk factors for pStage II CC, cN(+) was identified as an independent prognostic factor (hazard ratio: 2.06, 95% CI: 1.02-4.27, p = 0.04). CONCLUSION: Preoperatively over-staged cN cases had a poorer prognosis than cases without over-staging, indicating its potential as a prognostic factor. In addition to already known high risk factors in pStage II cases, the preoperative cStage may be an indication for adjuvant chemotherapy.

Predictors of the difficulty of transcervical subcarinal lymph node dissection for esophageal cancer.

BACKGROUND: Transmediastinal radical esophagectomy (TME) is a new minimally invasive approach without thoracotomy. However, the transcervical dissection of subcarinal lymph nodes (SCLN) is challenging. The shape or narrowness of the mediastinal space, particularly around the aortic arch to the tracheal bifurcation, may increase the difficulty of this procedure. The present study aimed to clarify predictors of the difficulty of transcervical SCLN dissection. METHODS: Patients who underwent TME between 2016 and 2019 were included (n = 126). Four indicators, the cervical angle, carina distance, aorta distance, and sternum distance, were defined as indicators of mediastinal narrowness by 3D-CT. The relationships between the difficulty of transcervical SCLN dissection and clinicopathological features, including the above indicators, were investigated. RESULTS: In a univariate analysis, the cervical angle (p = 0.023), aorta distance (p = 0.002), and middle thoracic tumor (p = 0.040) correlated with difficulty. The median cervical angle and aorta distance were 15° and 33 mm in difficult cases and 19° and 43 mm in easy cases, respectively. In a multivariate analysis, the short aorta distance (odds ratio: 7.96, p = 0.002) and middle thoracic tumor (odds ratio: 3.35, p = 0.042) were independent predictive factors. CONCLUSIONS: The cervical angle, aorta distance, and middle thoracic tumor may predict the difficulty of transcervical SCLN dissection. In difficult cases, a transhiatal approach should be combined for complete SCLN dissection.

Overexpression of Tetraspanin31 contributes to malignant potential and poor outcomes in gastric cancer.

Tetraspanin has important functions in many cancers by aggregating with various proteins that interact with intracellular signaling proteins. The molecular function of Tetraspanin31 (TSPAN31), located in the 12q14 amplified region in various cancers, remains unclear in gastric cancer (GC). We tested whether TSPAN31 acts as a cancer-promoting gene through its activation or overexpression in GC. We analyzed seven GC cell lines and 189 primary tumors, which were curatively resected in our hospital between 2011 and 2013. Overexpression of the TSPAN31 protein was frequently detected in three GC cell lines (42.9%) and 62 primary GC specimens (32.8%). Overexpression of TSPAN31 was significantly correlated with lymphatic invasion, venous invasion, more advanced pT and pN stages, and a higher recurrence rate. Moreover, TSPAN31 positivity was an independent factor predicting worse patient outcomes (p = 0.0283, hazard ratio 3.97). Ectopic overexpression of TSPAN31 facilitated cell proliferation of GC cells, and knockdown of TSPAN31 inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition of GC cells through the PI3K-Akt pathway and increased cell apoptosis in a TP53 mutation-independent manner. In vivo analysis also revealed knockdown of TSPAN31 suppressed tumor progression. In addition, knockdown of TSPAN31 improved chemosensitivity to cisplatin through the suppression of ABCC2. These findings suggest that TSPAN31 plays a crucial role in tumor-malignant potential through overexpression, highlighting its utility as a prognostic factor and a potential therapeutic target in GC.

Functions and Clinical Significance of CACNA2D1 in Gastric Cancer.

BACKGROUND: Voltage-gated calcium channels form as a complex of several subunits, among which the function of CACNA2D1, one of the genes encoding the α2δ subunit, remains unclear. The aim of our study was to investigate the role of CACNA2D1 and evaluate the efficacy of amlodipine, a blocker of CACNA2D1, in the treatment of gastric cancer (GC). METHODS: Knockdown experiments were performed on the human GC cell lines MKN7 and HGC27 using CACNA2D1 small interfering RNA (siRNA), and changes in cell proliferation, the cell cycle, apoptosis, migration, and invasion were assessed. The gene expression profiles of cells were examined using a microarray analysis. An immunohistochemical (IHC) analysis was conducted on samples obtained from 196 GC patients who underwent curative gastrectomy. In addition, the antitumor effects of amlodipine were investigated using a xenograft model. RESULTS: Cell proliferation, migration, and invasion were suppressed in CACNA2D1-depleted cells, and apoptosis was induced. The results of the microarray analysis showed that the apoptosis signaling pathway was enhanced via p53, BAX, and caspase 3 in CACNA2D1-depleted cells. A multivariate analysis identified high CACNA2D1 expression levels, confirmed by IHC, as an independent poor prognostic factor in GC patients. Moreover, subcutaneous tumor volumes were significantly smaller in a xenograft nude mouse model treated with a combination of amlodipine and cisplatin than in a model treated with cisplatin alone. CONCLUSIONS: The present study indicates that CACNA2D1 regulates the apoptosis signaling pathway and may have potential as a biomarker for cancer growth and as a therapeutic target for GC.

TRPV2 Promotes Cell Migration and Invasion in Gastric Cancer via the Transforming Growth Factor-ß Signaling Pathway.

BACKGROUND: Transient receptor potential vanilloid 2 (TRPV2) is a highly Ca2+-permeable ion channel that is involved in a number of cellular processes. It is expressed in various human cancers; however, the role of TRPV2 in gastric cancer (GC) remains poorly understood. METHODS: TRPV2 gene expression was knocked down in GC cell lines by small-interfering RNA (siRNA), and the biological roles of TRPV2 in the proliferation, migration, and invasion of GC cells were then investigated. The gene expression profile of GC was elucidated using a microarray analysis. TRPV2 expression in tumor tissue sections was analyzed by immunohistochemistry. RESULTS: The migration and invasion abilities of GC cells were inhibited by the knockdown of TRPV2. Moreover, the microarray assay revealed that TRPV2 was associated with the transforming growth factor (TGF)-ß signaling pathway. Immunohistochemical staining showed that the strong expression of TRPV2 correlated with lymphatic invasion, venous invasion, pathological T (pT), pathological N (pN), and a poor prognosis in GC patients. CONCLUSIONS: TRPV2 appeared to promote tumor migration and invasion via the TGF-ß signaling pathway, and the strong expression of TRPV2 was associated with a worse prognosis in GC patients.

Removal of small extracellular vesicles inhibits the progression of peritoneal dissemination in gastric cancer.

BACKGROUND: The prognosis of gastric cancer patients with peritoneal dissemination is extremely poor and effective treatment for peritoneal dissemination has not been established. Gastric cancer-derived small extracellular vesicles play an important role in the development of a favorable microenvironment for peritoneal metastasis and progression of peritoneal dissemination. Here, we aimed to investigate the transformation of gastric cancer cells by removing gastric cancer-derived small extracellular vesicles and to develop a novel therapy for inhibiting peritoneal dissemination. METHODS: Gastric cancer cells were cultured in medium containing gastric cancer- and peritoneal mesothelium-derived small extracellular vesicles and in medium from which small extracellular vesicles were removed by ultracentrifugation. Cell function assays were performed in vitro, and the alternations in gene expression in gastric cancer cells were analyzed. The inhibitory effect of intraperitoneal lavage on peritoneal dissemination was investigated in vivo as a method to remove gastric cancer-derived small extracellular vesicles. RESULTS: Removal of gastric cancer-derived small extracellular vesicles suppressed the proliferative and migrative abilities of gastric cancer cells and the adhesion of gastric cancer cells to peritoneal mesothelial cells. It altered the expression of several genes related to the cell cycle and epithelial-mesenchymal transition pathways of gastric cancer cells, leading to the inhibition of gastric cancer cell growth and peritoneal dissemination in vivo. CONCLUSIONS: Our study provides novel insights into a novel therapy for inhibiting the peritoneal dissemination of gastric cancer by targeting gastric cancer-derived small extracellular vesicles to improve the prognosis of gastric cancer patients with peritoneal metastasis.

Reduction of perioperative venous thrombus formation by antithrombotic peripherally inserted central catheter in esophageal cancer.

PURPOSE: Although a central venous catheter (CVC) is often needed perioperatively for intraoperative and nutritional management of esophageal cancer (EC), the catheter placement impacts the risk of venous thrombosis. We examined the risks of thrombus formation by catheter type, placement, and duration. METHODS: In total, 226 patients with EC were enrolled in this retrospective study. Patients were classified into one of three groups: those with a conventional CVC (cCVC), a peripherally inserted central catheter (PICC), or an antithrombogenic agent-coated PICC (secPICC). The thrombus formation and clinicopathological features were examined. RESULTS: The frequency of all types of thrombosis was significantly lower in the secPICC group (p < 0.01). Although deep vein thrombosis was frequent in the cCVC group, catheter thrombosis was frequent in the PICC group. In a univariate analysis in patients with the PICC and secPICC groups, less thrombus formation was observed in the secPICC (p = 0.01), short placement time (p = 0.02), and right-sided placement (p < 0.01). Furthermore, a multivariate analysis revealed that secPICC (p = 0.049) and right-sided placement (p = 0.04) significantly reduced rates of thrombus formation. CONCLUSION: In patients with EC, secPICC and right-sided placement reduce perioperative venous thrombus formation.

Glucose variability and predicted cardiovascular risk after gastrectomy.

PURPOSE: To investigate the correlation between glycemic trends and cardiovascular risk after gastrectomy for gastric cancer. METHODS: We enrolled 105 gastric cancer patients who underwent gastrectomy at our hospital between October 2017 and July 2020. Postoperative glucose concentrations, trends, and patterns were recorded using a continuous glucose monitoring (CGM) device. Cardiovascular risk was calculated using the Framingham stroke risk profile score (FSRPS), the Framingham risk score (FRS), and the Suita score. We examined the correlations between glycemic variability and cardiovascular risk scores. RESULTS: There were significant differences in the standard deviation (SD) of glucose levels between the high and low FSRPS groups (p = 0.049), the high and low FRS groups (p = 0.011), and the high and low Suita score groups (p = 0.044). The SD of glucose levels was significantly higher in patients with diabetes mellitus (DM) (p < 0.001) and those who underwent total gastrectomy (TG) (p = 0.017). Additionally, the CGM data available for 38 patients 1 year post-gastrectomy were analyzed for glucose level dynamics, and the SD was found to be significantly higher than that at 1 month (p < 0.001). CONCLUSION: Our findings suggest that long-term follow-up and therapeutic strategies tailored to glycemic trends may be necessary for gastric cancer patients after gastrectomy, especially those with DM and those who have undergone TG, to prevent cardiovascular events.

The survival after recurrence of colorectal cancer: a retrospective study focused on time to recurrence after curative resection.

PURPOSE: The significance of the duration of the recurrence-free survival after curative resection for colorectal cancer remains unclear. The purpose was to reveal the association between time to recurrence after surgery and the survival after recurrence. METHODS: Patients with stage II and III colorectal cancer who underwent curative resection between 2007 and 2015 were retrospectively reviewed (n = 645). Patients with recurrence after surgery (n = 133) were divided into 2 groups: early recurrence (within 13 months after surgery, n = 63) and late recurrence (more than 13 months after surgery, n = 70). The overall survival after recurrence and clinicopathological features were compared between early recurrence, late recurrence, and without recurrence groups. RESULTS: The overall survival after recurrence was significantly shorter in patients with early recurrence occurring at less than 13 months (hazard ratio: 1.70, p = 0.03). A high preoperative CA19-9 level (odds ratio [OR]: 2.38, p = 0.03), venous invasion (OR: 2.26, p = 0.03), and the absence of adjuvant chemotherapy (OR: 2.08, p = 0.04) were independently correlated with early recurrence. CONCLUSION: Early recurrence was associated with a poor prognosis after recurrence. Venous invasion correlated with early recurrence. Adjuvant chemotherapy may reduce the risk of early recurrence. These results indicate the importance of prudent surveillance and the aggressive application of adjuvant chemotherapy.

Dynamics of glucose levels after Billroth I versus Roux-en-Y reconstruction in patients who undergo distal gastrectomy.

PURPOSE: Recent studies have highlighted the importance of understanding trends in blood glucose levels. We examined the differences in blood glucose fluctuations according to the reconstruction method used after distal gastrectomy (DG) in patients with non-diabetic gastric cancer (GC). METHODS: Sixty-one patients who underwent DG followed by either Billroth 1 (B1) or Roux-en-Y (R-Y) reconstruction were enrolled in this study. We used flash continuous glucose monitoring (CGM), a new technique for assessing glycemic control, to document the post-gastrectomy glycemic profile. Immediately before discharge, a CGM sensor was placed subcutaneously to evaluate blood glucose trends for 2 weeks. RESULTS: The coefficient of variation of glucose levels was significantly higher in the Roux-en-Y (R-Y) group than in the Billroth I (B-I) group (p = 0.0260). The time below range (TBR, glucose levels of < 70 mg/dL) was also significantly higher in the R-Y group (p = 0.0115). Logistic regression analysis revealed that preoperative casual glucose levels of < 100 mg/dL and R-Y reconstruction were independently correlated with risk factors for a postoperative nocturnal TBR of > 30% (p = 0.006 and 0.042, respectively). CONCLUSION: Our findings provide new insights into the post-DG reconstruction method selected for patients with non-diabetic gastric cancer by assessing postoperative blood glucose fluctuations using flash CGM.

Role of Extracellular High-Mobility Group Box-1 as a Therapeutic Target of Gastric Cancer.

Background: High-mobility group box-1 (HMGB1) is involved in the tumorigenesis and metastasis of various cancers. The present study investigated the roles of extracellular HMGB1 in the progression of gastric cancer (GC) and the therapeutic effects of recombinant human soluble thrombomodulin (rTM) targeting HMGB1. Methods: The effects of extracellular HMGB1 and rTM on GC cells were assessed using proliferation and Transwell assays. Their effects on local tumor growth and metastasis were evaluated using subcutaneous tumor and liver metastasis mouse models, respectively. Plasma HMGB1 concentrations in GC patients were measured using ELISA. The relationships between plasma HMGB1 concentrations and the prognosis and clinicopathological factors of patients were also investigated. Results: GC proliferation, migration, and invasion abilities were promoted by increases in extracellular HMGB1 concentrations and alleviated by rTM. In the subcutaneous tumor model, local tumor growth was promoted by the addition of rhHMGB1 and alleviated by rTM. Similar changes occurred in the liver metastasis model. Recurrence-free survival (p < 0.01) and overall survival (p = 0.01) were significantly worse in patients with high plasma HMGB1 concentrations. Conclusion: Plasma HMGB1 concentrations are a prognostic marker in GC patients. Extracellular HMGB1 promotes cancer progression and has potential as a novel treatment target in GC cells for rTM.

Preoperative 3D-CT evaluation of the bronchial arteries in transmediastinal radical esophagectomy for esophageal cancer.

BACKGROUND: In transmediastinal esophagectomy (TME) with equivalent lymphadenectomy to transthoracic procedure, an understanding of surgical anatomy in the deep mediastinum near the aortic arch or tracheal bifurcation is essential for the safe procedure. The present study aimed to evaluate the bronchial arteries (BAs) with preoperative 3D-CT in TME. METHODS: Seventy-nine patients with thoracic esophageal cancer undergoing TME were examined by preoperative 3D-CT to evaluate BA variations in the number, branching pattern, and mediastinal course. For the right BAs (RBAs) crossing the esophagus, the mediastinal courses in transcervical view were classified in relation to the esophagus and tracheobronchi and compared with surgical findings. RESULTS: A total of 107 RBAs (1.35/person) were confirmed on preoperative 3D-CT. Of these, 61 (57.0%) crossed the esophagus dorsally (type Ed), and the remaining 46 (43.0%) crossed the esophagus ventrally (type Ev). During the left transcervical procedure, all type Ed RBAs were identified and mostly preserved (57/61, 93.4%) whereas most type Ev RBAs were identified (39/46, 84.8%), but more than half were sacrificed (26/46, 56.5%) for lymphadenectomy. The blood loss during the transcervical procedure was 17.0 ± 55.8 ml. The total number of dissected mediastinal lymph nodes was 23.7 ± 9.3. There were no significant complications related to extensive lymphadenectomy. CONCLUSIONS: Preoperative 3D-CT evaluation is useful to understand the mediastinal courses of BAs specific to the transcervical approach, which may allow BAs to be handled more carefully according to the type during surgery, contributing to a safer procedure in the deep mediastinum.

ANO9 regulates PD-L2 expression and binding ability to PD-1 in gastric cancer.

The function of ANO9 in gastrointestinal cancer remains unclear. We investigated the biological behaviors and clinical prognostic values of ANO9 in gastric cancer (GC). Knockdown experiments were performed on human GC cell lines using ANO9 siRNA. Eighty-four primary tissue samples from patients with advanced GC were examined immunohistochemically (IHC). Knockdown of ANO9 reduced the progression of cancer cells in MKN7 and MKN74 cells. A microarray analysis revealed that ANO9 regulated PD-L2 via interferon (IFN)-related genes. We confirmed using flow cytometry that the depletion of ANO9 reduced the binding ability to PD-1 by downregulating the expression of PD-L2 in MKN7 and MKN74 cells. IHC revealed a correlation between the expression of ANO9 and PD-L2 and also that the strong expression of ANO9 was an independent poor prognostic factor in patients with advanced GC. The present results indicate that ANO9 regulates PD-L2 and binding ability to PD-1 via IFN-related genes in GC. Therefore, ANO9 has potential as a biomarker and target of immune checkpoint blockage (ICB) for GC.

Expression and Role of CFTR in Human Esophageal Squamous Cell Carcinoma.

BACKGROUND: The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-dependent chloride (Cl-) anion conducting channel, and its role in esophageal squamous cell carcinoma (ESCC) was examined in the present study. METHODS: Overexpression experiments were conducted on human ESCC cell lines following the transfection of a CFTR plasmid, and changes in cell proliferation, the cell cycle, apoptosis, migration, and invasion were assessed. A microarray analysis was performed to examine gene expression profiles. Fifty-three primary tumor samples collected from ESCC patients during esophagectomy were subjected to an immunohistochemical analysis. RESULTS: Transfection of the CFTR plasmid into the ESCC KYSE 170 and KYSE 70 cell lines suppressed cell proliferation, migration, and invasion and induced apoptosis. The microarray analysis showed the up-regulated expression of genes involved in the p38 signaling pathway in CFTR plasmid-transfected KYSE 170 cells. Immunohistochemical staining revealed a relationship between the CFTR expression pattern at the invasive front and the pN category. A relationship was also observed between the weak expression of CFTR at the invasive front and a shorter postoperative survival in a prognostic analysis. CONCLUSIONS: The overexpression of CFTR in ESCC activated the p38 signaling pathway and was associated with a good patient prognosis. These results indicate the potential of CFTR as a mediator of and/or a biomarker for ESCC.

Functional Analysis and Clinical Significance of Chloride Channel 2 Expression in Esophageal Squamous Cell Carcinoma.

BACKGROUND: Chloride channel 2 (CLCN2) was recently shown to affect tumor behavior. The present study examined the functions of CLCN2 in the regulation of genes that play a role in tumor progression, as well as its clinicopathological significance in esophageal squamous cell carcinoma (ESCC). METHODS: Knockdown experiments were conducted using CLCN2-small-interfering RNA, and changes in proliferation, survival, and cellular movement in human ESCC cell lines were investigated. A microarray analysis of gene expression profiles in CLCN2-depleted ESCC cells was conducted. Fifty-four primary ESCC samples were examined by immunohistochemistry (IHC). RESULTS: The strong expression of CLCN2 was detected in TE5 and KYSE70 cells. Downregulated expression of CLCN2 enhanced proliferation and decreased apoptosis, whereas its upregulation inhibited proliferation and increased apoptosis. The effects of lubiprostone, a CLCN2 activator, were also investigated. In lubiprostone-treated cells, proliferation was inhibited and apoptosis was increased. The microarray analysis demonstrated that interferon (IFN) signaling-related genes were downregulated in CLCN2-depleted cells. IHC showed the presence of CLCN2 in the cytoplasm and cell membranes of ESCC cells. The prognostic analysis revealed a relationship between weak CLCN2 expression and shorter overall survival. CONCLUSIONS: The present results indicate that tumor progression is regulated by CLCN2 through its effects on IFN signaling. Furthermore, weak CLCN2 expression was associated with poorer outcomes in ESCC patients. The present study will contribute to a clearer understanding of the role of CLCN2 as a mediator of ESCC, as well as its use as a biomarker for this cancer.

Amlodipine and Verapamil, Voltage-Gated Ca2+ Channel Inhibitors, Suppressed the Growth of Gastric Cancer Stem Cells.

BACKGROUND: The membrane transporters activated in cancer stem cells (CSCs) are the target of novel cancer therapies for gastric cancer. The present study investigated ion channel expression profiles in gastric CSCs (GCSCs). METHODS: Cells strongly expressing CD44 were separated from MKN74 cells, a human gastric cancer cell line, by fluorescence-activated cell sorting (FACS), and GCSCs were identified based on tumorsphere formation. Gene expression profiles in GCSCs were examined by a microarray analysis. RESULTS: Among MKN74 cells, CD44 messenger RNA levels were higher in CSCs than in non-CSCs. These CSCs also exhibited resistance to cisplatin. The microarray analysis revealed that the expression of several genes related to voltage-gated Ca2+ channels (VGCCs), including CACNA2D1 and CACNB4, was upregulated. The cytotoxicities of the CACNA2D1 inhibitor amlodipine and the CACNB4 inhibitor verapamil were greater at lower concentrations in CSCs than in non-CSCs, and markedly reduced tumorsphere numbers. Tumor volumes were significantly smaller in a xenograft nude mouse model treated with amlodipine or verapamil in combination with cisplatin than in that treated with cisplatin alone. CONCLUSIONS: The present results indicate that VGCCs play a role in maintaining CSCs, and demonstrated the potential of their specific inhibitors, amlodipine and verapamil, as targeted therapeutic agents against gastric cancer.

Oligometastasis scoring system for predicting survival of patients with colorectal liver metastasis after hepatectomy.

BACKGROUND: Oligometastasis, the presence of a small number of resectable metastatic tumors, usually has favorable outcomes. Here we examined whether the novel oligometastatic score (OLGS), which divides the number of colorectal liver metastases (CRLMs) by the time from colorectal resection to liver recurrence, better predicts CRLM patient survival than the commonly used clinical risk score. METHODS: A total of 143 patients who underwent curative hepatectomy for CRLMs between 2007 and 2018 were analyzed. We investigated their clinical characteristics and outcomes using OLGS. RESULTS: Of the 143 CRLM patients, 70 had synchronous CRLMs and 73 had metachronous CRLMs. Patients with metachronous CRLMs were divided into OLGS-low (n = 59) and OLGS-high (n = 14) subgroups. The 5-year overall survival (OS) rates after hepatectomy differed significantly between the subgroups (p < .001). In the multivariate Cox model, a high OLGS was an independent predictor of 5-year OS (p < .001), and the hazard ratio (HR) of the OLGS-high group (HR = 7.171) was higher than that of the high clinical risk score group (HR = 4.337). CONCLUSION: The OLGS, a simple and handy scoring system, better predicts the 5-year OS of patients with CRLMs after hepatectomy and warrants prospective validation.

LRRC8A influences the growth of gastric cancer cells via the p53 signaling pathway.

BACKGROUND: Leucin-rich repeat containing protein A (LRRC8A), a component of the volume-regulated anion channel (VRAC), is activated by cell swelling and mediates regulatory volume decrease. We previously reported the expression of and important roles for several ion transporters in various gastrointestinal cancers, which have potential as novel targets for cancer treatment; however, the significance of LRRC8A in gastric cancer (GC) remains unclear. MATERIALS AND METHODS: Knockdown experiments were performed by transfecting human GC cell lines with LRRC8A siRNA. Gene expression was then assessed using microarray analysis. Samples from 132 patients with GC were subjected to immunohistochemistry (IHC) for LRRC8A, and its relationships with clinicopathological factors and prognosis were examined. RESULTS: The knockdown of LRRC8A suppressed the proliferation and movement of cells and enhanced apoptosis. The results of the microarray analysis showed the up- or down-regulated expression of genes related to the p53 signaling pathway (JNK, p53, p21, Bcl-2, and FAS) in LRRC8A-knockdown cells. IHC revealed a correlation between the expression of LRRC8A and the pT status (p = 0.015), and multivariate analysis identified the strong expression of LRRC8A as an independent prognostic factor for 5-year survival in GC patients (p = 0.0231). CONCLUSIONS: The present results indicate that LRRC8A functions as a mediator of and/or biomarker for GC.