CACNA2D1 regulates the progression and influences the microenvironment of colon cancer.

BACKGROUND: Calcium voltage-gated channel auxiliary subunit alpha 2/delta 1 (CACNA2D1), a gene encoding a voltage-gated calcium channel, has been reported as an oncogene in several cancers. However, its role in colon cancer (CC) remains unclear. This study aimed to investigate the function of CACNA2D1 and its effect on the microenvironment in CC. METHODS: Immunohistochemistry (IHC) analysis was performed on samples collected from 200 patients with CC who underwent curative colectomy. Knockdown experiments were performed using CACNA2D1 siRNA in the human CC cell lines HCT116 and RKO, and cell proliferation, cycle, apoptosis, and migration were then analyzed. The fibroblast cell line CCD-18Co was co-cultured with CC cell lines to determine the effect of CACNA2D1 on fibroblasts and the relationship between CACNA2D1 and the cancer microenvironment. Gene expression profiles of cells were analyzed using microarray analysis. RESULTS: IHC revealed that high CACNA2D1 expression was an independent poor prognostic factor in patients with CC and that CACNA2D1 expression and the stroma are correlated. CACNA2D1 depletion decreased cell proliferation and migration; CACNA2D1 knockdown increased the number of cells in the sub-G1 phase and induced apoptosis. CCD-18Co and HCT116 or RKO cell co-culture revealed that CACNA2D1 affects the cancer microenvironment via fibroblast regulation. Furthermore, microarray analysis showed that the p53 signaling pathway and epithelial-mesenchymal transition-associated pathways were enhanced in CACNA2D1-depleted HCT116 cells. CONCLUSIONS: CACNA2D1 plays an important role in the progression and the microenvironment of CC by regulating fibroblasts and may act as a biomarker for disease progression and a therapeutic target for CC.

Cancer Stem Cells of Hepatocellular Carcinoma Are Suppressed by the Voltage-gated Calcium Channel Inhibitor Amlodipine.

BACKGROUND/AIM: The membrane transporters activated in cancer stem cells (CSCs) are the target of novel cancer therapies for hepatocellular carcinoma (HCC). The present investigation demonstrated the expression profiles of ion channels in CSCs of HCC. MATERIALS AND METHODS: Cells that highly expressed aldehyde dehydrogenase 1 family member A1 (ALDH1A1) were separated from HepG2 cells, a human HCC cell line, by fluorescence-activated cell sorting, and CSCs were identified based on the formation of tumorspheres. Gene expression profiles in CSCs were investigated using microarray analysis. RESULTS: Among HepG2 cells, ALDH1A1 messenger RNA level was higher in CSCs than in non-CSCs. Furthermore, CSCs exhibited resistance to cisplatin and had the capacity to redifferentiate. The results of the microarray analysis of CSCs showed the up-regulated expression of several genes related to ion channels, such as calcium voltage-gated channel auxiliary subunit gamma 4 (CACNG4). The cytotoxicity of the CACNG4 inhibitor amlodipine was higher at lower concentrations in CSCs than in non-CSCs, and markedly decreased the number of tumorspheres. The cell population among HepG2 cells that highly expressed ALDH1A1 was also significantly reduced by this inhibitor. CONCLUSION: CACNG4 plays a role in maintaining CSCs, and its inhibitor, amlodipine, could potentially be a targeted therapeutic agent against HCC.

[Identification of ion channel/transporter expression profiles in digestive cancer stem cells for novel targeting therapy].

Recent evidence suggests that the targeting of membrane transporters specifically activated in cancer stem cells (CSCs) is an important strategy for cancer therapy. The objectives of the present study were to investigate the ion channel expression profiles in digestive CSCs. Cells strongly expressing CSC markers, such as ALDH1A1 and CD44, were separated from the human esophageal squamous cell carcinoma, gastric cancer, and pancreatic cancer cell lines using fluorescence-activated cell sorting, and CSCs were identified based on tumorsphere formation. Messenger RNA levels of CSC markers were higher in CSCs than in non-CSCs. These CSCs also exhibited resistance to anticancer agents. The microarray analysis revealed that the expression of transient receptor potential vanilloid 2 (TRPV2), voltage-gated calcium channels (VGCCs), and voltage-gated potassium channels (VGKCs) were upregulated in esophageal, gastric, and pancreatic CSCs, respectively, compared with non-CSCs. The TRPV2 inhibitor tranilast, VGCCs inhibitors amlodipine and verapamil, and VGKC inhibitor 4-aminopyridine exhibited greater cytotoxicity in CSCs compared with non-CSCs, and their inhibitory effects were also confirmed in a xenograft model in nude mice. Taking these results, phase I/II study to investigate clinical safety and efficacy of neoadjuvant combination chemotherapy of tranilast in advanced esophageal squamous cell carcinoma (TNAC study) is ongoing. These researches identified a role of ion channels in the persistence of CSCs and suggested that their inhibitors may have potential as a therapeutic agent for digestive cancers.

Cancer Stem Cells of Esophageal Adenocarcinoma are Suppressed by Inhibitors of TRPV2 and SLC12A2.

BACKGROUND: The potential of membrane transporters activated in cancer stem cells (CSCs) as new therapeutic targets for cancer is attracting increasing interest. Therefore, the present study examined the expression profiles of ion transport-related molecules in the CSCs of esophageal adenocarcinoma (EAC). METHODS: Cells that highly expressed aldehyde dehydrogenase 1 family member A1 (ALDH1A1) were separated from OE33 cells, a human Barrett's EAC cell line, by fluorescence-activated cell sorting. CSCs were identified based on the formation of tumorspheres. Gene expression profiles in CSCs were examined by a microarray analysis. RESULTS: Among OE33 cells, ALDH1A1 messenger RNA levels were higher in CSCs than in non-CSCs. Furthermore, CSCs exhibited resistance to cisplatin and had the capacity to redifferentiate. The results of the microarray analysis of CSCs showed the up-regulated expression of several genes related to ion channels/transporters, such as transient receptor potential vanilloid 2 (TRPV2) and solute carrier family 12 member 2 (SLC12A2). The cytotoxicities of the TRPV2 inhibitor tranilast and the SLC12A2 inhibitor furosemide were higher at lower concentrations in CSCs than in non-CSCs, and both markedly reduced the number of tumorspheres. The cell population among OE33 cells that highly expressed ALDH1A1 also was significantly decreased by these inhibitors. CONCLUSIONS: Based on the present results, TRPV2 and SLC12A2 are involved in the maintenance of CSCs, and their specific inhibitors, tranilast and furosemide, respectively, have potential as targeted therapeutic agents for EAC.

Effects of TRPV2 on the Expression of PD-L1 and Its Binding Ability to PD-1 in Gastric Cancer.

BACKGROUND: Transient receptor potential vanilloid 2 (TRPV2) is a member of the TRP superfamily of non-specific cation channels with functionally diverse roles. We herein investigated the effects of TRPV2 on the expression of programmed cell death-ligand 1 (PD-L1) and its binding ability to programmed cell death-1 (PD-1) in gastric cancer (GC). METHODS: Knockdown (KD) experiments were performed on human GC cell lines using TRPV2 small-interfering RNA. The surface expression of PD-L1 and its binding ability to PD-1 were analyzed by flow cytometry. Eighty primary tissue samples were assessed by immunohistochemistry (IHC), and the relationships between IHC results, clinicopathological factors, and patient prognosis were analyzed. The molecular mechanisms underlying the effects of TRPV2 on the intracellular ion environment were also investigated. RESULTS: TRPV2-KD decreased the expression level of PD-L1 in NUGC4 and MKN7 cells, thereby inhibiting its binding to PD-1. A survival analysis revealed that 5-year overall survival rates were significantly lower in the TRPV2 high expression and PD-L1-positive groups. In IHC multivariate analysis of GC patients, high TRPV2 expression was identified as an independent prognostic factor. Furthermore, a positive correlation was observed between the expression of TRPV2 and PD-L1. An immunofluorescence analysis showed that TRPV2-KD decreased the intracellular concentration of calcium ([Ca2+]i). Treatment with ionomycin/PMA (phorbol 12-myristate 13-acetate), which increased [Ca2+]i, upregulated the protein expression of PD-L1 and promoted its binding to PD-1. CONCLUSIONS: The surface expression of PD-L1 and its binding ability to PD-1 in GC were regulated by TRPV2 through [Ca2+]i, indicating the potential of TRPV2 as a biomarker and target of immune checkpoint blockage for GC.

Effects and risk factors of TAS-102 in real-world patients with metastatic colorectal cancer, EROTAS-R study.

BACKGROUND: Trifluridine/tipiracil (TAS-102) is an anticancer drug for metastatic colorectal cancer (CRC). This study aimed to analyze the effects and risk factors about effects of TAS-102 in real-world patients with metastatic CRC (the EROTAS-R study). METHODS: This study retrospectively analyzed 271 patients aged ≥ 20 years who underwent TAS-102 for metastatic CRC at nine related institutions from 2014 to 2021. Therapeutic results of TAS-102 + bevacizumab (Bev) and TAS-102, effect predictors, adverse events (AE), and AE predictors were examined. RESULTS: The backgrounds of all cases were as follows: average age, 66.7 ± 10.9 years; male ratio, 59.5%; performance status (PS) 0/1/2, 43.5%/50.6%/5.9%; and tumor site right/left, 25.5%/74.5%. The therapeutic results of 109 cases receiving TAS-102 + Bev and 162 cases receiving TAS-102 were as follows: disease control rate, 53.2% vs. 28.0% (p < 0.01); progressive free survival (PFS), 6.2 vs. 4.2 months (p < 0.01); and overall survival (S), 11.8 vs. 9.3 months (p = 0.03). Multivariate analysis for effect-related factors (odds ratio (OR), 95%confidence interval (CI)) showed the following: PS1 + 2 (0.257, 0.134-0.494, p < 0.01) and a combination of Bev (3.052, 1.598-5.827, p < 0.01). The rates of grade 3 AE for TAS-102 + Bev and TAS-102 were 53.2% and 48.8%, respectively (p = 0.47). Various AE predictors were as follows: male sex (p = 0.69), age ≥ 75 years (p = 0.59), PS1 + 2 (p = 0.20), body surface area < 1.53 m2 (p = 0.26), eGFR < 50 ml/min (p = 0.02), and AST ≥ 50 IU/L (p = 0.64). CONCLUSION: A better OS and PFS comparing TAS-102 + Bev to TAS-102 for CRC was achieved in a large number of real-world patients.

Value of the Tumor-Stroma Ratio and Structural Heterogeneity Measured by a Novel Semiautomatic Image Analysis Technique for Predicting Survival in Patients With Colon Cancer.

BACKGROUND: The tumor-stroma ratio and intratumor stromal heterogeneity have been identified as prognostic factors for several carcinomas. Recent advancements in image analysis technologies and their application to medicine have enabled detailed analysis of clinical data beyond human cognition. OBJECTIVE: This study aimed to investigate the tumor-stroma ratio and intratumor stromal heterogeneity measured using a novel objective and semiautomatic method with image analysis. DESIGN: A retrospective cohort design. SETTINGS: Single institution. PATIENTS: This study included patients who underwent curative colectomy for colon cancer. MAIN OUTCOME MEASURES: The survival analyses between tumor-stroma ratio or intratumor stromal heterogeneity high and low groups after colectomy were assessed in multivariate analyses. RESULTS: Two hundred patients were divided into 2 groups based on the median tumor-stroma ratio and intratumor stromal heterogeneity values. The 5-year overall survival and relapse-free survival rates after colectomy significantly differed between the high and low tumor-stroma ratio or intratumor stromal heterogeneity groups. Multivariate analysis identified low tumor-stroma ratio (HR: 1.90, p = 0.03) and high intratumor stromal heterogeneity (HR: 2.44, p = 0.002) as independent poor prognostic factors for relapse-free survival. The tumor-stroma ratio and intratumor stromal heterogeneity correlated with the duration from curative surgery to recurrence. Furthermore, postoperative recurrence within 2 years was predicted with higher accuracy by using the tumor-stroma ratio or intratumor stromal heterogeneity than by using the pathological stage. In a validation cohort, interobserver agreement was assessed by 2 observers, and Cohen's κ coefficient for the tumor-stroma ratio (κ value: 0.70) and intratumor stromal heterogeneity (κ value: 0.60) revealed a substantial interobserver agreement. LIMITATIONS: This study was limited by its retrospective, single-institution design. CONCLUSIONS: Tumor-stroma ratio and intratumor stromal heterogeneity calculated using image analysis software have potential as imaging biomarkers for predicting the survival of patients with colon cancer after colectomy. See Video Abstract at http://links.lww.com/DCR/C114 . VALOR DE LA PROPORCIN DE ESTROMA TUMORAL Y LA HETEROGENEIDAD ESTRUCTURAL MEDIDOS POR UNA NUEVA TCNICA DE ANLISIS DE IMGENES SEMIAUTOMTICA PARA PREDECIR LA SUPERVIVENCIA EN PACIENTES CON CNCER DE COLON: ANTECEDENTES:La proporción de estroma tumoral y la heterogeneidad del estroma intratumoral han sido identificados como factores pronósticos para varios tipos de carcinomas. Los avances recientes en cuanto a las tecnologías de análisis de imágenes y sus aplicaciones en la medicina, han permitido un análisis detallado de los datos clínicos más allá del conocimiento humano.OBJETIVO:Investigar la relación del estroma tumoral y la heterogeneidad del estroma intratumoral calculados mediante un nuevo método objetivo y semiautomático para el análisis de imágenes.DISEÑO:Diseño de cohorte retrospectivo.AJUSTES:Institución única.PACIENTES:Pacientes sometidos a colectomía curativa por cáncer de colon.PRINCIPALES MEDIDAS DE RESULTADO:Los análisis de supervivencia entre la relación del estroma tumoral o la heterogeneidad del estroma intratumoral entre los grupos con valores altos y bajos tras la colectomía, fueron evaluados en análisis multivariados.RESULTADOS:Fueron divididos 200 pacientes en dos grupos basados en la mediana de la proporción con respecto a los valores del estroma tumoral y la heterogeneidad del estroma intratumoral. Las tasas de supervivencia general a los 5 años y de supervivencia libre de recaídas después de la colectomía, difirieron significativamente entre los grupos con índice de estroma tumoral o heterogeneidad del estroma intratumoral altos y bajos. El análisis multivariante identificó una proporción de estroma tumoral baja (cociente de riesgos instantáneos: 1.90, p = 0.03) y una heterogeneidad estromal intratumoral alta (cociente de riesgos instantáneos: 2.44, p = 0.002) como factores independientes de mal pronóstico para la supervivencia libre de recaídas. La proporción de estroma tumoral y la heterogeneidad del estroma intratumoral se correlacionaron con la duración de la recurrencia desde la cirugía.Además, la recurrencia posoperatoria dentro de los 2 años se predijo con mayor precisión mediante el uso del índice de estroma tumoral o la heterogeneidad del estroma intratumoral que mediante el uso del estadio patológico. En una cohorte de validación, la concordancia interobservador fue evaluada por dos observadores, y el coeficiente Kappa de Cohen para la proporción de estroma tumoral y la heterogeneidad estromal intratumoral reveló una concordancia interobservador sustancial (valor Kappa: 0.70, 0.60, respectivamente).LIMITACIONES:Este estudio estuvo limitado por su diseño retrospectivo de una sola institución.CONCLUSIONES:La proporción del estroma tumoral y la heterogeneidad del estroma intratumoral calculadas mediante software de análisis de imágenes tienen potencial como biomarcadores de imagen para predecir la supervivencia de los pacientes con cáncer de colon tras la colectomía. Consulte Video Resumen en http://links.lww.com/DCR/C114 . (Traducción-Dr. Osvaldo Gauto ).

Minimally Invasive Surgery for Colorectal Cancer During the COVID-19 Pandemic in a Tertiary Medical Facility in Japan.

BACKGROUND/AIM: The coronavirus disease 2019 (COVID-19) pandemic has reduced hospital visits due to concerns regarding infection and also resulted in cancer screening delays. These changes may have had an impact on the progression of colorectal cancer (CRC). Therefore, the present study investigated the effects of the COVID-19 pandemic on minimally invasive surgery (MIS) for CRC using a correlation analysis of clinical outcomes before and during the COVID-19 pandemic. PATIENTS AND METHODS: The present study targeted CRC patients who underwent MIS between January 2018 and December 2019 (pre-COVID-19) and between April 2020 and March 2021 (COVID-19). A comparison analysis of clinical, surgical, and pathological findings between the pre-COVID-19 and COVID-19 groups was performed. RESULTS: Ninety-one patients underwent MIS for CRC pre-COVID-19 and 67 during COVID-19. The number of CRC cases detected by fecal occult blood tests was slightly higher in the pre-COVID-19 group than that in the COVID-19 group. Re-evaluations of laparoscopic videos revealed that the number of cases of surgical T4 CRC resected with the combined resection of the adjacent organs was significantly higher in the COVID-19 group than that in the pre-COVID-19 group (16.4 vs. 4.4%, p=0.010). Furthermore, surgical times were significantly longer in the COVID-19 group than those in the pre-COVID-19 group (p<0.001). Pathological findings showed that the number of pT4 cases was significantly higher in the COVID-19 group than that in the pre-COVID-19 group (p=0.026). CONCLUSION: The number of T4 CRC cases was higher during than before the COVID-19 pandemic, with increases in the surgical difficulty of MIS.

Anoctamin 5 regulates the cell cycle and affects prognosis in gastric cancer.

BACKGROUND: Anoctamin 5 (ANO5)/transmembrane protein 16E belongs to the ANO/ transmembrane protein 16 anion channel family. ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types. Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types. However, it remains unclear whether ANO5 acts as a plasma membrane chloride channel, and its expression and functions in gastric cancer (GC) have not been investigated. AIM: To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC. METHODS: Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines, and changes in cell proliferation, cell cycle progression, apoptosis, and cellular movement were assessed. The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis. Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department. RESULTS: Reverse transcription-quantitative polymerase chain reaction (PCR) and western blotting demonstrated high ANO5 mRNA and protein expression, respectively, in NUGC4 and MKN45 cells. In these cells, ANO5 silencing inhibited cell proliferation and induced apoptosis. In addition, the knockdown of ANO5 inhibited G1-S phase progression, invasion, and migration. The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes, such as CDKN1A, CDK2/4/6, CCNE2, and E2F1, in ANO5-depleted NUGC4 cells. The expression of these genes was verified using reverse transcription-quantitative PCR. Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis. Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC (P = 0.0457). CONCLUSION: ANO5 regulates the cell cycle progression by regulating the expression of cyclin-associated genes and affects the prognosis of patients with GC. These results may provide insights into the role of ANO5 as a key mediator in tumor progression and/or promising prognostic biomarker for GC.

NADPH Oxidase 2 Has a Crucial Role in Cell Cycle Progression of Esophageal Squamous Cell Carcinoma.

BACKGROUND: NADPH oxidases (NOXs) are transmembrane proteins that generate reactive oxygen species. Recent studies have reported that NOXs are involved in tumor progression in various cancers. However, the expression and role of NOX2 in esophageal squamous cell carcinoma (ESCC) remain unclear. This study aimed to clarify the pathophysiologic role of NOX2 in patients with ESCC and cell lines. METHODS: Two human ESCC cell lines (TE5 and KYSE170) were used for NOX2 transfection experiments, and the effects on cell proliferation, cell cycle, cell motility, and cell survival were analyzed. An mRNA microarray analysis was also performed to assess gene expression profiles. Additionally, NOX2 immunohistochemistry was performed on 130 primary ESCC tumor samples to assess the prognostic value of NOX2 in patients with ESCC. RESULTS: NOX2 depletion significantly inhibited cell proliferation with the G0/G1 arrest and resulted in apoptosis in two cell lines. Microarray analysis revealed a strong relationship between NOX2 gene expression and the signaling pathway of cell cycle regulation by the B-cell translocation gene 2 (BTG2) family, including BTG2, CCNE2, E2F1, and CDK2 genes. Immunohistochemical staining revealed that high NOX2 protein expression was significantly associated with deeper tumor invasion and selected as one of the independent prognostic factors associated with the 5-year OS rate in patients with ESCC. CONCLUSIONS: NOX2 expression in ESCC cells affects tumorigenesis, especially cell cycle progression via the BTG2-related signaling pathway, as well as the prognosis of patients with ESCC. NOX2 may be a novel biomarker and therapeutic target for ESCC.

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.

The Effect of Preoperative Oral Antibiotics in the Prevention of Surgical Site Infection after Laparoscopic Colorectal Cancer Surgery: A Propensity Score Matching Study.

OBJECTIVES: Recent findings suggest that the combination of mechanical bowel preparation (MBP) and preoperative oral antibiotics (OA) decreases the risk of surgical site infection (SSI) in colorectal surgery; however, this remains controversial. The present study examined the efficacy of OA plus MBP in laparoscopic colorectal cancer (CRC) surgery using propensity score matching (PSM). METHODS: A total of 1080 patients with CRC underwent MBP followed by laparoscopic surgery between 2007 and 2019. OA was administered to all patients with CRC who underwent colectomy from 2018. PSM was performed to compare the effects of OA plus MBP (OA) versus MBP only (non-OA) on the rate of superficial SSI. RESULTS: Overall, 128 patients received OA. Significant differences were observed in age, the American Society of Anesthesiologists performance status (ASA-PS), liver disease, and preoperative serum albumin (Alb) between the OA and non-OA groups. The enrolled patients were matched using PSM into two groups based on the following factors: sex, age, body mass index, ASA-PS, diabetes mellitus, liver disease, Alb, and tumor location, which resulted in the disappearance of significant differences. A univariate analysis showed that blood loss of 100 g or more, non-OA, and preoperative chemotherapy or radiation correlated with SSI (p = 0.021, 0.010, 0.038). A multivariate analysis of these three variables identified blood loss of 100 g or more and non-OA as independent risk factors for SSI (hazard ratio (HR): 3.238, p = 0.031; HR: 2.547, p = 0.033). CONCLUSIONS: The present study revealed that OA plus MBP markedly reduced SSI rate. OA with MBP needs to be adopted in laparoscopic CRC surgery.

Roles of voltage­gated potassium channels in the maintenance of pancreatic cancer stem cells.

The targeting of membrane proteins that are activated in cancer stem cells (CSCs) represents one of the key recent strategies in cancer therapy. The present study analyzed ion channel expression profiles and functions in pancreatic CSCs (PCSCs). Cells strongly expressing aldehyde dehydrogenase 1 family member A1 (ALDH1A1) were isolated from the human pancreatic PK59 cell line using fluorescence­activated cell sorting, and PCSCs were identified based on tumorsphere formation. Microarray analysis was performed to investigate the gene expression profiles in PCSCs. ALDH1A1 messenger RNA levels were higher in PCSCs compared with non­PCSCs. PCSCs were resistant to 5­fluorouracil and capable of redifferentiation. The results of the microarray analysis revealed that gene expression related to ion channels, including voltage­gated potassium channels (Kv), was upregulated in PCSCs compared with non­PCSCs. 4­Aminopyridine (4­AP), a potent Kv inhibitor, exhibited greater cytotoxicity in PCSCs compared with non­PCSCs. In a xenograft model in nude mice, tumor volumes were significantly lower in mice inoculated with PK59 cells pre­treated with 4­AP compared with those in mice injected with non­treated cells. The present results identified a role of Kv in the persistence of PCSCs and suggested that the Kv inhibitor 4­AP may have potential as a therapeutic agent for pancreatic carcinoma.

The expression of the alpha1 subunit of Na+/K+-ATPase is related to tumor development and clinical outcomes in gastric cancer.

BACKGROUND: The Na+/K+-ATPase alpha1 subunit (ATP1A1) is a critical component of Na+/K+-ATPase (NKA), a membrane pump that maintains a low intracellular Na+/K+ ratio and retains cellular volume and osmolarity. ATP1A1 was recently implicated in tumor behavior. Therefore, the present study investigated the role of ATP1A1 in patients with gastric cancer (GC). METHODS: Knockdown experiments were conducted on human GC cell lines using ATP1A1 siRNA, and its effects on proliferation, the cell cycle, apoptosis, and cellular movement were examined. Gene expression profiling was performed by a microarray analysis. Primary tumor samples from 192 GC patients who underwent gastrectomy were subjected to an immunohistochemical analysis. RESULTS: High ATP1A1 expression levels were observed in NUGC4 and MKN74 cells. Cell proliferation was suppressed and apoptosis was induced by the siRNA-induced knockdown of ATP1A1. The microarray analysis showed that knockdown of ATP1A1 leads to the up-regulated expression of genes involved in the interferon (IFN) signaling pathway, such as STAT1, STAT2, IRF1, and IRF9. Furthermore, the depletion of ATP1A1 altered the phosphorylation of the MAPK pathway. The immunohistochemical analysis revealed that the expression of ATP1A1 was associated with the histological type, venous invasion, and the pathological T stage. Furthermore, the prognostic analysis showed a relationship between high ATP1A1 expression levels and poor postoperative survival. CONCLUSIONS: ATP1A1 appears to regulate tumor progression by altering IFN signaling, and high ATP1A1 expression levels were associated with poor postoperative survival in GC patients. The present results provide novel insights into the function of ATP1A1 as a mediator and/or biomarker of GC.

Impact of Inferior Mesenteric Artery Lymph Node Metastasis on the Prognosis of Left-sided Colorectal Cancer.

BACKGROUND/AIM: This study aimed to investigate the impact of the inferior mesenteric artery (IMA) lymph node metastasis [IMALN (+)] on prognosis in left-sided colorectal cancer (LCRC). PATIENTS AND METHODS: A total of 285 patients with stage III LCRC and 118 patients with stage IV LCRC who underwent resection of primary tumor between 2005 and 2016 were included. RESULTS: IMALN (+) patients (n=10) had worse overall survival (OS) than patients without IMA lymph node metastasis [IMALN (-); n=275] in stage III LCRC (p=0.007). Multivariate analysis revealed that IMALN (+) was a prognostic factor in stage III LCRC (OS, HR=3.09, p=0.043). Conversely, there was no difference between the OS of IMALN (+) and stage IV LCRC with distant lymph node metastasis only [stage IV LCRC (LYM); n=21; p=0.434]. CONCLUSION: The prognosis of IMALN (+) was worse than that of IMALN (-); it was similar to that of stage IV LCRC (LYM).

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.

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.