Novel choledochojejunostomy technique "T-shaped anastomosis" for preventing the development of postoperative cholangitis in pancreatoduodenectomy: A propensity score matching analysis.

Background: There have been few studies of countermeasures against postoperative cholangitis, a serious complication after pancreaticoduodenectomy (PD) that impairs quality of life. Objective: To evaluate our recently developed, novel method of choledochojejunostomy with a larger anastomotic diameter, the "T-shaped anastomosis." Methods: The study included 261 cases of PD. The T-shaped choledochojejunostomy technique was performed with an additional incision for a distance greater than half the diameter of the bile duct at the anterior wall of the bile duct and the anterior wall of the elevated jejunum. To compensate for potential confounding biases between the standard anastomosis group (n = 206) and the T-shaped anastomosis group (n = 55), we performed propensity score matching (PSM). The primary endpoint was the incidence of medium-term postoperative cholangitis adjusted for PSM. Results: In the PSM analysis, 54 patients in each group were matched, and the median bile duct diameter measured by preoperative CT was 8.8 mm versus 9.3 mm, the rate of preoperative biliary drainage was 31% versus 37%, the incidence of cholangitis within 1 month before surgery was 9% versus 13%, and the incidence of postoperative bile leakage was 2% versus 2%, with no significant differences. The incidence of medium-term postoperative cholangitis was 15% versus 4%, and multivariate logistic regression revealed that T-shaped choledochojejunostomy was an independent predictor of a reduced incidence of cholangitis (odds ratio, 0.17, 95% CI 0.02-0.81; p = 0.024). Conclusions: The T-shaped choledochojejunostomy technique was shown to be effective with a significant reduction in the incidence of medium-term postoperative cholangitis. Clinical trial identification: UMIN000050990.

Evaluating staging laparoscopy indications for pancreatic cancer based on resectability classification and treatment strategies for patients with positive peritoneal washing cytology.

Introduction: The prognosis of pancreatic ductal adenocarcinoma (PDAC) in patients with positive peritoneal washing cytology (CY1) is poor. We aimed to evaluate the results of staging laparoscopy (SL) and treatment efficacy in CY1 patients based on a resectability classification. Methods: We retrospectively reviewed 250 patients with PDAC who underwent SL before the initial treatment between 2017 and 2023 at the University of Toyama. Results: The breakdown of cases by resectability classification was resectable (R):borderline resectable (BR):unresectable locally advanced (UR-LA) = 131:48:71 cases. The frequency of CY1 increased in proportion to the degree of local progression (R:BR:UR-LA = 20:23:34%), but the frequencies of liver metastasis or peritoneal dissemination were comparable (R:BR:UR-LA = 6.9:6.3:8.5%). Most CY1 patients received gemcitabine along with nab-paclitaxel therapy. The CY-negative conversion rates (R:BR:UR-LA = 70:64:52%) and conversion surgery rates (R:BR:UR-LA = 40:27:9%) were inversely proportional to the degree of local progression.Comparing H0P0CY1 factors for each classification, patients with H0P0CY1 had significantly more pancreatic body or tail carcinoma and tumor size ≥32 mm in R patients, whereas in BR patients, duke pancreatic monoclonal antigen type 2 (DUPAN-2) ≥ 230 U/mL was a significant factor. In contrast, no significant factors were observed in UR-LA patients. Conclusion: The CY1 rates, CY-negative conversion rates, and conversion surgery rates varied according to local progression. In the case of R and BR, SL could be considered in patients with pancreatic body or tail carcinoma, large tumor size, or high DUPAN-2 level. In UR-LA, SL might be considered for all patients.

Efficacy of staging laparoscopy for resectable pancreatic cancer on imaging and the therapeutic effect of systemic chemotherapy for positive peritoneal cytology.

BACKGROUND: The frequency and prognosis of positive peritoneal washing cytology (CY1) in resectable pancreatic ductal adenocarcinoma (R-PDAC) remains unclear. The objective of this study was to identify the clinical implications of CY1 in R-PDAC and staging laparoscopy (SL). METHODS: We retrospectively analyzed 115 consecutive patients with R-PDAC who underwent SL between 2018 and 2022. Patients with negative cytology (CY0) received radical surgery after neoadjuvant chemotherapy, while CY1 patients received systemic chemotherapy and were continuously evaluated for cytology. RESULTS: Of the 115 patients, 84 had no distant metastatic factors, 22 had only CY1, and nine had distant metastasis. Multivariate logistic regression revealed that larger tumor size was an independent predictor of the presence of any distant metastatic factor (OR: 6.30, p = .002). Patients with CY1 showed a significantly better prognosis than patients with distant metastasis (MST: 24.6 vs. 18.9 months, p = .040). A total of 11 CY1 patients were successfully converted to CY-negative, and seven underwent conversion surgery. There was no significant difference in overall survival between patients with CY0 and those converted to CY-negative. CONCLUSION: SL is effective even for R-PDAC. The prognosis of CY1 patients converted to CY-negative is expected to be similar to that of CY0 patients.

A case of squamous cell carcinoma of the breast achieved a pathological complete response after dose-dense AC + dose-dense PTX.

BACKGROUND: Squamous cell carcinoma (SCC) of the breast is a rare form of breast cancer, accounting for approximately 0.1% of all breast cancers. It is known for its rapid tumor growth and poor prognosis with no established treatment. CASE PRESENTATION: A 56-year-old woman was diagnosed with breast SCC with axillary, supraclavicular and internal thoracic lymph node metastases. She received neoadjuvant chemotherapy (NAC) with dose-dense doxorubicin and cyclophosphamide (AC) followed by dose-dense paclitaxel (PTX). This treatment resulted in a pathological complete response (pCR) after breast-conserving surgery. The patient was then treated with radiotherapy. She remained free of recurrence for three years postoperatively. CONCLUSIONS: We report a rare case of breast SCC treated with preoperative dose-dense chemotherapy, resulting in pCR and allowing breast-conserving surgery.

Is surgical resection justified for pancreatic ductal adenocarcinoma with distant abdominal organ metastasis? A position paper by experts in pancreatic surgery at the Joint Meeting of the International Association of Pancreatology (IAP) & the Japan Pancreas Society (JPS) 2022 in Kyoto.

Pancreatic ductal adenocarcinoma (PDAC) is a typical refractory malignancy, and many patients have distant organ metastases at diagnosis, such as liver metastasis and peritoneal dissemination. The standard treatment for unresectable PDAC with distant organ metastasis (UR-M) is chemotherapy, but the prognosis remained poor. However, with recent dramatic developments in chemotherapy, the prognosis has gradually improved, and some patients have experienced marked shrinkage or disappearance of their metastatic lesions. With this trend, attempts have been made to resect a small number of metastases (so-called oligometastases) in combination with the primary tumor or to resect the primary and metastatic tumor in patients with a favorable response to anti-cancer treatment after a certain period of time (so-called conversion surgery). An international consensus meeting on surgical treatment for UR-M PDAC was held during the Joint Congress of the 26th Meeting of the International Association of Pancreatology (IAP) and the 53rd Annual Meeting of the Japan Pancreas Society (JPS) in Kyoto in July 2022. The presenters showed their indications for and results of surgical treatment for UR-M PDAC and discussed their advantages and disadvantages with the experts. Although these reports were limited to a small number of patients, findings suggest that these surgical treatments for patients with UR-M PDAC who have had a significant response to chemotherapy may contribute to a prognosis of prolonged survival. We hope that this article summarizing the discussion and agreements at the meeting will serve as the basis for future trials and guidelines.

Laparoscopic distal pancreatectomy for pancreatic tail cancer in a 100-year-old patient.

We present the case of a 100-year-old man with no specific symptoms. Computed tomography (CT) revealed a 34 mm tumor in the pancreatic tail, which was diagnosed as pancreatic cancer by biopsy. CT and magnetic resonance imaging showed that the tumor was resectable, and there were no noncurative factors on staging laparoscopy (cT3N0M0: cStage IIA). His performance status was good, and hypertension was the only comorbidity. A cardiologist, respiratory physician, and anesthesiologist examined the patient and determined that his condition was suitable for surgery. His postoperative predicted mortality rate was 0.9% using the American College of Surgeons risk calculator. We administered synbiotics and nutrients before surgery and introduced preoperative rehabilitation to improve his activities of daily living (ADL) as well as respiratory training to prevent postoperative pneumonia. Regarding the invasiveness of the surgery, we performed laparoscopic distal pancreatectomy with D1 lymphadenectomy. The patient was discharged on postoperative day 17, without any major complications. When performing pancreatectomy in older adults, it is important to fully assess preoperative tolerance and perioperative risk and prevent worsening of ADL by introducing nutritional therapy and rehabilitation.

The use of an artificial intelligence algorithm for circulating tumor cell detection in patients with esophageal cancer.

Despite recent advances in multidisciplinary treatments of esophageal squamous cell carcinoma (ESCC), patients frequently suffer from distant metastasis after surgery. For numerous types of cancer, circulating tumor cells (CTCs) are considered predictors of distant metastasis, therapeutic response and prognosis. However, as more markers of cytopathological heterogeneity are discovered, the overall detection process for the expression of these markers in CTCs becomes increasingly complex and time consuming. In the present study, the use of a convolutional neural network (CNN)-based artificial intelligence (AI) for CTC detection was assessed using KYSE ESCC cell lines and blood samples from patients with ESCC. The AI algorithm distinguished KYSE cells from peripheral blood-derived mononuclear cells (PBMCs) from healthy volunteers, accompanied with epithelial cell adhesion molecule (EpCAM) and nuclear DAPI staining, with an accuracy of >99.8% when the AI was trained on the same KYSE cell line. In addition, AI trained on KYSE520 distinguished KYSE30 from PBMCs with an accuracy of 99.8%, despite the marked differences in EpCAM expression between the two KYSE cell lines. The average accuracy of distinguishing KYSE cells from PBMCs for the AI and four researchers was 100 and 91.8%, respectively (P=0.011). The average time to complete cell classification for 100 images by the AI and researchers was 0.74 and 630.4 sec, respectively (P=0.012). The average number of EpCAM-positive/DAPI-positive cells detected in blood samples by the AI was 44.5 over 10 patients with ESCC and 2.4 over 5 healthy volunteers (P=0.019). These results indicated that the CNN-based image processing algorithm for CTC detection provides a higher accuracy and shorter analysis time compared to humans, suggesting its applicability for clinical use in patients with ESCC. Moreover, the finding that AI accurately identified even EpCAM-negative KYSEs suggested that the AI algorithm may distinguish CTCs based on as yet unknown features, independent of known marker expression.

Repair using the pectoralis major musculocutaneous flap for refractory anastomotic leakage after total esophagectomy.

BACKGROUND: The pectoralis major musculocutaneous flap (PMMF) is a pedicled flap often used as a reconstruction option in head and neck surgery, especially in cases with poor wound healing. However, applying PMMF after esophageal surgery is uncommon. We report here, the case of a successfully repaired refractory anastomotic fistula (RF) after total esophagectomy, by PMMF. CASE PRESENTATION: A 73-year-old man had a history of hypopharyngolaryngectomy, cervical esophagectomy, and reconstruction using a free jejunal graft for hypopharyngeal carcinosarcoma at the age of 54. He also received conservative treatment for pharyngo-jejunal anastomotic leakage (AL), then postoperative radiation therapy. This time, he was diagnosed with carcinosarcoma in the upper thoracic esophagus; cT3rN0M0, cStageII, according to the Japanese Classification of Esophageal Cancer 12th Edition. As a salvage surgery, thoracoscopic total resection of the esophageal remnant and reconstruction using gastric tube via posterior mediastinal route was performed. The distal side of the jejunal graft was cut and re-anastomosed with the top of the gastric tube. An AL was observed on the 6th postoperative day (POD), and after 2 months of conservative treatment was then diagnosed as RF. The 3/4 circumference of the anterior wall of the gastric tube was ruptured for 6 cm in length, and surgical repair using PMMF was performed on POD71. The edge of the defect was exposed and the PMMF (10 × 5 cm) fed by thoracoacromial vessels was prepared. Then, the skin of the flap and the wedge of the leakage were hand sutured via double layers with the skin of the flap facing the intestinal lumen. Although a minor AL was observed on POD19, it healed with conservative treatment. No complications, such as stenosis, reflux, re-leakage, were observed over 3 years of postoperative follow-up. CONCLUSIONS: The PMMF is a useful option for repairing intractable AL after esophagectomy, especially in cases with large defect, as well as difficulties for microvascular anastomosis due to previous operation, radiation, or wound inflammation.

miR-877-3p as a Potential Tumour Suppressor of Oesophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: MicroRNAs (miRNAs) are abnormally expressed and involved in the pathogenesis of various carcinomas. The present study aimed to identify novel miRNA genes associated with the pathogenesis and prognosis of oesophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: The miRNA profiling of 873 genes was performed using surgically resected oesophageal tissues from 35 patients with ESCC to identify candidate miRNAs. To examine the biological activities of candidate miRNAs, their proliferative, invasive, and migratory abilities were evaluated in ESCC cells subjected to miRNA mimic-mediated over-expression. The miRNA expression levels of the selected candidate miRNAs were analysed in the resected oesophageal tissues of 76 patients with ESCC from the two cohorts and correlated with the clinicopathological parameters. RESULTS: Among the four candidate miRNAs identified by miRNA profiling, miR-877-3p was selected for subsequent analyses. In vitro analyses showed that the over-expression of miR-877-3p significantly suppressed the proliferation, invasion, and migration of ESCC cell lines compared with those of control cells. In the analyses of clinical specimens, the expression of miR-877-3p was down-regulated in ESCC tissues compared with that in adjacent normal oesophageal tissues. The down-regulation of miR-877-3p expression in ESCC tissues was significantly associated with advanced local progression and lymphatic involvement. The miR-877-3p down-regulation was also significantly associated with poor disease-free and disease-specific survival. CONCLUSION: miR-877-3p acts as a tumour suppressor gene in ESCC cells, and its down-regulation in ESCC tissues is associated with a poor prognosis. Thus, miR-877-3p may serve as a novel prognostic marker and promising therapeutic target.

A 47-Year-Old Man with Advanced Distal Pancreatic Carcinoma and an Initial Partial Response to Chemotherapy Requiring Celiac Axis Reconstruction of the Common Hepatic Artery and Left Gastric Artery.

BACKGROUND Distal pancreatectomy with en bloc celiac artery resection (DP-CAR) is a curative surgical method for locally advanced pancreatic body cancer; however, arterial reconstruction remains controversial in this procedure. This report presents the case of a 47-year-old man with advanced distal pancreatic carcinoma and initial partial response to chemotherapy who required celiac axis reconstruction of the common hepatic artery and left gastric artery. CASE REPORT A 47-year-old man had loss of appetite. He had a 40-mm hypovascular tumor extending from the pancreatic body to the tail, invading around the celiac artery, common hepatic artery, left gastric artery, and splenic artery. We initiated chemotherapy concurrent with chemo-radiotherapy with S-1 administration. After chemo-radiotherapy, computed tomography (CT) showed tumor shrinkage, indicating partial response, but soft tissue CT density surrounding the celiac axis arteries persisted. We conducted conversion surgery. When the common hepatic artery was clamped during surgery, the intrahepatic arterial blood flow reduced; thus, we reconstructed the middle hepatic artery to the common hepatic artery. The left gastric artery was also reconstructed using the second jejunal artery to prevent ischemic gastropathy. Histopathologic examination showed no tumor cells in the specimen; thus, R0 resection was achieved. CONCLUSIONS Arterial reconstruction can be an option for R0 resection in DP-CAR when hepatic arterial blood flow is reduced due to an intraoperative common hepatic artery clamping test.

Comparison Between FOLFIRINOX and nal-IRI/FL as Second-line Treatment After Gemcitabine Plus Nab-paclitaxel for Pancreatic Cancer.

BACKGROUND/AIM: The regimen of nanoliposomal irinotecan plus 5-fluorouracil and leucovorin (Nal-IRI/FL) was approved in Japan as second-line chemotherapy after gemcitabine-based treatment for pancreatic ductal adenocarcinoma (PDAC) in 2020. We examined the difference in outcome between patients treated with second-line folinic acid, fluorouracil, irinotecan hydrochloride and oxaliplatin (FOLFIRINOX) and those treated with nal-IRI/FL after first-line gemcitabine and nab-paclitaxel (GnP). PATIENTS AND METHODS: The outcomes of 34 patients with PDAC who received second-line FOLFIRINOX (n=21) or nal-IRI/FL (n=13) after GnP at our Department from January 2016 to June 2021 were reviewed retrospectively. RESULTS: Patient backgrounds did not differ between the groups. Dose reduction was more frequently required for treatment with FOLFIRINOX than with nal-IRI/FL (86% vs. 46%, p=0.022). Pegfilgrastim and aprepitant were used more frequently in the FOLFIRINOX group (both p<0.01). Progression-free survival (5.9 vs. 8.3 months) and overall survival (9.1 vs. 11.2 months) did not differ significantly between the groups. The frequency of grade 3 (Common Terminology Criteria for Adverse Events) or higher adverse events was similar between the groups. All-grade peripheral neuropathy was more common in the FOLFIRINOX group (100% vs. 77%, p=0.048). CONCLUSION: FOLFIRINOX and nal-IRI/FL as second-line therapy after GnP provided similar prognoses, although supportive treatment and dose reduction were more frequently required for FOLFIRINOX.

Transcriptomic profiling on localized gastric cancer identified CPLX1 as a gene promoting malignant phenotype of gastric cancer and a predictor of recurrence after surgery and subsequent chemotherapy.

BACKGROUND: Localized gastric cancer (GC) becomes fatal once recurring. We still have room for improving their prognoses. METHODS: Transcriptomic analysis was done on surgically resected specimens of 16 patients with UICC stage III GC who underwent curative gastrectomy and adjuvant oral fluoropyrimidine monotherapy. Four of them were free from disease for longer than 5 years, and the others experienced metachronous metastasis within 2 years after surgery. Quantitative RT-PCR determined mRNA expression levels of primary gastric cancer tissues, which were collected from 180 patients who underwent gastric resection for stage II-III GC without preoperative treatment between 2001 and 2014. We tested alteration of malignant phenotypes including drug resistance of GC cell lines by siRNA and shRNA-mediated knockdown and forced expression experiments. RESULTS: CPLX1 was identified as a candidate biomarker for GC recurrence among 57,749 genes. Inhibiting and forced expression experiments indicated that CPLX1 promotes proliferation, motility, and invasiveness of GC cells, and decreases apoptosis and sensitivity to fluorouracil. Subcutaneous xenograft mouse models revealed that shRNA-mediated knockdown of CPLX1 also attenuated tumor growth of MKN1 cells in vivo. Overexpression of CPLX1 in gastric cancer tissue correlated with worse prognosis and was an independent risk factor for peritoneal recurrence in subgroups receiving adjuvant chemotherapy. CONCLUSIONS: CPLX1 may represent a biomarker for recurrence of gastric cancer and a target for therapy.

Downregulation of ROBO4 in Pancreatic Cancer Serves as a Biomarker of Poor Prognosis and Indicates Increased Cell Motility and Proliferation Through Activation of MMP-9.

BACKGROUND: The axon guidance gene family, SLIT/ROBO pathway, controls neural network formation, which correlates with the development of several cancers. METHODS: We found through analysis of the public database that ROBO4, one of the axon guidance molecules among the SLIT/ROBO family, is significantly downregulated in primary pancreatic cancer tissues compared with adjacent normal tissues. We carried out transfection experiments using three pancreatic cancer cell lines (MiaPaCa-2, BxPC-3, and SW1990) and one pancreatic duct epithelial cell line (HPDE6c7). A total of 51 clinical samples were then examined by immunohistochemical staining to find an association between ROBO4 expression at the protein level, clinical characteristics, and surgical outcomes. RESULTS: ROBO4 overexpression suppressed the invasion and migration abilities in MiaPaCa-2 and BxPC-3, while ROBO4 siRNA transfection to SW1990 and HPDE6c7 enhanced those activities. PCR-based profiling detected MMP-9 as a candidate downstream target of ROBO4, which was validated by decreased MMP-9 activity after the ROBO4 overexpression assay. High ROBO4 expression clinical samples had significantly better overall survival rather than low ROBO4 cases (P = 0.048). CONCLUSION: These findings suggest that decreased ROBO4 expression activates malignant phenotypes in cancer cells and is correlated with poor survival outcomes in pancreatic cancer.

Serum Carboxypeptidase Activity and Genotype-Stratified CA19-9 to Detect Early-Stage Pancreatic Cancer.

BACKGROUND AND AIMS: Serum diagnostic markers of early-stage pancreatic ductal adenocarcinoma (PDAC) are needed, especially for stage I disease. As tumors grow and cause pancreatic atrophy, markers derived from pancreatic parenchyma such as serum carboxypeptidase A (CPA) activity lose diagnostic performance. We evaluated, with CA19-9, serum CPA as a marker of early pancreatic cancer. METHODS: Serum CPA activity levels were measured in 345 controls undergoing pancreatic surveillance, divided into 2 sets, set 1 being used to establish a reference range. Variants within the CPA1 locus were sought for their association with pancreatic CPA1 expression to determine if such variants associated with serum CPA levels. A total of 190 patients with resectable PDAC were evaluated. RESULTS: Among controls, those having 1 or more minor alleles of CPA1 variants rs6955723 or rs2284682 had significantly higher serum CPA levels than did those without (P = .001). None of the PDAC cases with pancreatic atrophy had an elevated CPA. Among 122 PDAC cases without atrophy, defining serum CPA diagnostic cutoffs by a subject's CPA1 variants yielded a diagnostic sensitivity of 18% at 99% specificity (95% confidence interval [CI], 11.7-26) (vs 11.1% sensitivity using a uniform diagnostic cutoff); combining CPA with variant-stratified CA19-9 yielded a sensitivity of 68.0% (95% CI, 59.0-76.2) vs 63.1% (95% CI, 53.9- 71.7) for CA19-9 alone; and among stage I PDAC cases, diagnostic sensitivity was 51.9% (95% CI, 31.9-71.3) vs 37.0% (95% CI, 19.4-57.6) for CA19-9 alone. In the validation control set, the variant-stratified diagnostic cutoff yielded a specificity of 98.2%. CONCLUSION: Serum CPA activity has diagnostic utility before the emergence of pancreatic atrophy as a marker of localized PDAC, including stage I disease.

Blockade of CHRNB2 signaling with a therapeutic monoclonal antibody attenuates the aggressiveness of gastric cancer cells.

Here, we evaluated the therapeutic potential of antibodies (Abs) targeting cholinergic receptor nicotinic beta 2 subunit (CHRNB2) in gastric cancer. To investigate the effects of these Abs on malignant phenotypes in vitro and in mouse xenograft models, we generated gene knockouts through genome editing, performed RNA interference-mediated knockdown of gene expression, and ectopically expressed CHRNB2 in gastric cancer cells. The effects of anti-CHRNB2 Abs on the proliferation of cancer cells were evaluated both in vitro and in vivo. We determined the effects of Chrnb2 deficiency on mice and the clinical significance of CHRNB2 expression in gastric cancer clinical specimens. Knockdown of CHRNB2 attenuated gastric cancer cell proliferation, whereas forced overexpression of CHRNB2 increased cell proliferation. Knockout of CHRNB2 significantly influenced cell survival and functions associated with metastasis. The effects of polyclonal Abs targeting the C- and N-termini of CHRNB2 guided the development of anti-CHRNB2 monoclonal Abs that inhibited the growth of gastric cancer cells in vitro and in vivo. Pathway analysis revealed that CHRNB2 interfered with signaling through the PI3K-AKT and JAK-STAT pathways. Chrnb2-deficient mice exhibited normal reproduction, organ functions, and motor functions. CHRNB2 regulates multiple oncological phenotypes associated with metastasis, and blockade of CHRNB2 expression using specific Abs shows promise for controlling metastasis in gastric cancer.

G-protein subunit gamma-4 expression has potential for detection, prediction and therapeutic targeting in liver metastasis of gastric cancer.

BACKGROUND: The liver is the most common site for haematogenous metastasis of gastric cancer, and liver metastasis is fatal. METHODS: We conducted a transcriptomic analysis between metastatic foci in the liver, primary tumour and adjacent tissues from gastric cancer patients with metastasis limited to the liver. We determined mRNA expression levels in tumour tissues of 300 patients with gastric cancer via quantitative RT-PCR. The oncogenic phenotypes of GNG4 were determined with knockdown, knockout and forced expression experiments. We established and compared subcutaneous and liver metastatic mouse xenograft models of gastric cancer to reveal the roles of GNG4 in tumorigenesis in the liver. RESULTS: GNG4 was upregulated substantially in primary gastric cancer tissues as well as liver metastatic lesions. High levels of GNG4 in primary cancer tissues were associated with short overall survival and the likelihood of liver recurrence. Functional assays revealed that GNG4 promoted cancer cell proliferation, the cell cycle and adhesiveness. Tumour formation by GNG4-knockout cells was moderately reduced in the subcutaneous mouse model and strikingly attenuated in the liver metastasis mouse model. CONCLUSIONS: GNG4 expression may provide better disease monitoring for liver metastasis, and GNG4 may be a novel candidate therapeutic target for liver metastasis.

Hepatic metastasis of gastric cancer is associated with enhanced expression of ethanolamine kinase 2 via the p53-Bcl-2 intrinsic apoptosis pathway.

BACKGROUND: Gastric cancer (GC) with hepatic metastasis has a poor prognosis. Understanding the molecular mechanisms involved in hepatic metastasis may contribute to the development of sensitive diagnostic biomarkers and novel therapeutic strategies. METHODS: We performed transcriptome analysis of surgically resected specimens from patients with advanced GC. One of the genes identified as specifically associated with hepatic metastasis was selected for detailed analysis. GC cell lines with knockout of the candidate gene were evaluated in vitro and in vivo. Expression of the candidate gene was analysed in GC tissues from 300 patients. RESULTS: Ethanolamine kinase 2 (ETNK2) was differentially upregulated in GC patients with hepatic metastasis. ETNK2 expression was elevated in GC cell lines derived from haematogenous metastases. ETNK2 knockout significantly suppressed proliferation, invasion, and migration; increased apoptosis; reduced Bcl-2 protein expression; and increased phosphorylated p53 expression. In mouse xenograft models, ETNK2 knockout virtually abolished hepatic metastasis. Stratification of GC patients based on ETNK2 mRNA level revealed significant associations between high ETNK2 tumour expression and both hepatic recurrence and worse prognosis. CONCLUSIONS: Upregulation of ETNK2 in GC enhances hepatic metastasis, possibly via dysregulation of p53-Bcl-2-associated apoptosis. ETNK2 expression may serve as a biomarker for predicting hepatic recurrence and a therapeutic target.

Therapeutic monoclonal antibody targeting of neuronal pentraxin receptor to control metastasis in gastric cancer.

BACKGROUND: Controlling metastasis is essential for improving the prognosis of patients with gastric cancer (GC). Here, we aimed to identify a molecule required for GC metastasis and to investigate its potential utility as a target for the development of therapeutic antibodies (Abs). METHODS: Transcriptome and bioinformatics analyses of human GC cell lines identified the neuronal pentraxin receptor (NPTXR) as a candidate molecule. NPTXR function was probed by modulating its expression in GC cells and assessing the effects on intracellular signaling and malignant behaviors in vitro and in mouse xenograft models. We also generated anti-NPTXR Abs and Nptxr-/- mice, and assessed the clinical significance of NPTXR expression in GC specimens. RESULTS: NPTXR mRNA expression in clinical specimens was associated with disease progression and was significantly higher in tissues from GC patients with distant metastasis compared with those without. NPTXR regulated expression of genes involved in metastatic behaviors as well as activation of the PI3K-AKT-mTOR, FAK-JNK, and YAP signaling pathways. NPTXR silencing promoted caspase-mediated apoptosis and attenuated GC cell proliferation, cell cycle progression, migration, invasion, adhesion, stem cell-like properties, and resistance to 5-fluorouracil in vitro, and also inhibited the tumorigenicity of GC cells in vivo. Anti-NPTXR Abs inhibited GC peritoneal metastasis in mice. Nptxr-/- mice showed no abnormalities in reproduction, development, metabolism, or motor function. CONCLUSIONS: NPTXR plays an essential role in controlling the malignant behavior of GC cells in vitro and in vivo. NPTXR-targeting Abs may thus have utility as novel diagnostic tools and/or treatment modalities for GC.

Fraser extracellular matrix complex subunit 1 promotes liver metastasis of gastric cancer.

Liver metastasis is often fatal in patients with gastric cancer, therefore, we aimed to identify genes associated with the mechanisms of liver metastasis of gastric cancer (GC) and to investigate their potential to predict recurrence and to serve as targets of therapy. Recurrence pattern-specific transcriptome analysis was performed to identify liver metastasis-associated genes. A stable knockout cell line was generated to investigate metabolic pathways that contribute to the malignant phenotype in vitro and vivo. Three hundred GC patients were analyzed to demonstrate an association between gene expression levels and clinicopathological parameters. As a results extracellular matrix complex subunit 1 (FRAS1) was identified as a liver metastasis-associated gene. Pathway analysis revealed that FRAS1 expression was significantly correlated with the expression of genes encoding TGFB1, MAP1B, AHNAK, BMP2, MUC1, BIRC5, MET, CDH1, RB1 and MKI67. FRAS1 expression was associated with the activation of the EGFR and PI3K signaling pathways. The proliferation ability of FRAS1 knockout cell line (FRAS1-KO) was inhibited compared to that of the parent cell line through caspase activity increment and cell cycle alteration. FRAS1-KO cells exhibited increased responsiveness to oxygen stress and diminished stemness, invasiveness, and migration. Mouse models of GC revealed decreases in tumor formation and generation of metastasis by FRAS1-KO cells. Moreover, the cumulative liver recurrence rate was significantly increased in patients with GC with high FRAS1 expression levels. We concluded that FRAS1 contributes to the malignant phenotype of GC, especially liver metastasis, and may therefore serve as a predictive marker or a target for treating liver metastasis.