The efficacy of wrapping with polyglycolic acid mesh and fibrin glue in preventing clinically relevant pancreatic fistula after minimally invasive distal pancreatectomy (WRAP Study): study protocol for a multicenter randomized controlled trial in Japan.

BACKGROUND: Postoperative pancreatic fistula (POPF) continues to be the most common complication after distal pancreatectomy (DP). Recent advancements in surgical techniques have established minimally invasive distal pancreatectomy (MIDP) as the standard treatment for various conditions, including pancreatic cancer. However, MIDP has not demonstrated a clear advantage over open DP in terms of POPF rates, indicating the need for additional strategies to prevent POPF in MIDP. This trial (WRAP study) aims to evaluate the efficacy of wrapping the pancreatic stump with polyglycolic acid (PGA) mesh and fibrin glue in preventing clinically relevant (CR-) POPF following MIDP. METHODS: This multicenter, randomized controlled trial will include patients scheduled for laparoscopic or robotic DP for tumors in the pancreatic body and/or tail. Eligible participants will be centrally randomized into either the control group (Group A) or the intervention group (Group B), where the pancreatic stump will be reinforced by PGA mesh and fibrin glue. In both groups, pancreatic transection will be performed using a bioabsorbable reinforcement-attached stapler. A total of 172 patients will be enrolled across 14 high-volume centers in Japan. The primary endpoint is the incidence of CR-POPF (International Study Group of Pancreatic Surgery grade B/C). DISCUSSION: The WRAP study will determine whether the reinforcement of the pancreatic stump with PGA mesh and fibrin glue, a technique whose utility has been previously debated, could become the best practice in the era of MIDP, thereby enhancing its safety. TRIAL REGISTRATION: This trial was registered with the Japan Registry of Clinical Trials on June 15, 2024 (jRCTs032240120).

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.

Targeting Pancreatic Cancer with Novel Plumbagin Derivatives: Design, Synthesis, Molecular Mechanism, In Vitro and In Vivo Evaluation.

Pancreatic tumors grow in an "austerity" tumor microenvironment characterized by nutrient deprivation and hypoxia. This leads to the activation of adaptive pathways in pancreatic cancer cells, promoting tolerance to nutrition starvation and aggressive malignancy. Conventional anticancer drugs are often ineffective against tumors that grow in such austerity condition. Plumbagin, a plant-derived naphthoquinone, has shown potent preferential cytotoxicity against pancreatic cancer cells under nutrient-deprived conditions. Therefore, we synthesized a series of plumbagin derivatives and found that 2-(cyclohexylmethyl)-plumbagin (3f) was the most promising compound with a PC50 value of 0.11 µM. Mechanistically, 3f was found to inhibit the PI3K/Akt/mTOR signaling pathways, leading to cancer cell death under nutrient-deprived conditions. In vivo studies using pancreatic cancer xenograft mouse models confirmed the efficacy of 3f, demonstrating significant inhibition of tumor growth in a dose-dependent manner. Compound 3f represents a highly promising lead for anticancer drug development based on an antiausterity strategy.

Nicolaioidesin C: An Antiausterity Agent Shows Promising Antitumor Activity in a Pancreatic Cancer Xenograft Mouse Model.

Human pancreatic tumors are hypovascular in nature, and their tumor microenvironment is often characterized by hypoxia and severe nutrient deprivation due to uncontrolled heterogeneous growth, a phenomenon known as "austerity". However, pancreatic tumor cells have the inherent ability to adapt and thrive even in such low nutrient and hypoxic microenvironments. Anticancer drugs such as gemcitabine and paclitaxel, which target rapidly proliferating cells, are often ineffective against nutrient-deprived pancreatic cancer cells. In order to overcome this limitation, the search for novel agents that can eliminate cancer cells' adaptations to nutrition starvation, also known as "antiausterity" agents, represents a promising strategy to make the cancer cells susceptible to treatment. The natural product (+)-nicolaioidesin C (Nic-C) was found to have potent antiausterity activity against the PANC-1 human pancreatic cancer cell line in a nutrient-deprived condition. However, its efficacy in vivo remained untested. To address this, we synthesized Nic-C in its racemic form and evaluated its antitumor potential in a human pancreatic cancer xenograft model. Nic-C inhibited pancreatic cancer cell migration and colony formation and significantly inhibited tumor growth in MIA PaCa-2 xenografts in a dose-dependent manner. Furthermore, Nic-C inhibited the Akt/mTOR and autophagy signaling pathways in both in vitro and in vivo studies. Metabolomic profiling of in vivo tumor samples suggests that Nic-C downregulates amino acid metabolism while upregulating sphingolipid metabolism.

Prognostic factors in conversion surgery following nab-paclitaxel with gemcitabine and subsequent chemoradiotherapy for unresectable locally advanced pancreatic cancer: Results of a dual-center study.

Background: In pancreatic ductal adenocarcinoma (PDAC), only radical surgery improves long-term survival. We focused on surgical outcome after induction gemcitabine along with nab-paclitaxel (GnP) and subsequent chemoradiotherapy (CRT) with S-1 administration for unresectable locally advanced (UR-LA) PDAC. Methods: We retrospectively analyzed 144 patients with UR-LA PDAC between 2014 and 2020. The first-line regimen of induction chemotherapy was GnP for 125 of the 144 patients. Of the 125 patients who received GnP, 41 who underwent radical resection after additional preoperative CRT were enrolled. We evaluated the prognostic factors for this treatment strategy. Results: The median length of preoperative GnP was 8.8 months, and 30 (73%) patients had normalized CA19-9 levels. R0 resection was achieved in 36 (88%) patients. Postoperative major complications of ≥Clavien-Dindo grade IIIa developed in 16 (39%) patients. With a median follow-up of 35.2 months, 14 (34%) patients developed distant metastasis postoperatively. Using the Kaplan-Meier method, prognostic analysis of the 41 cases revealed the 3-y overall survival rate (OS) was 77.4% and the 5-y OS was 58.6%. In univariate analysis, length of preoperative GnP (≥8 months), CA19-9 normalization, and good nutritional status at operation (prognostic nutritional index ≥41.7) were significantly associated with favorable prognosis. Multivariate analysis revealed CA19-9 normalization (hazard ratio [HR] 0.23; P = .032) and prognostic nutritional index ≥41.7 (HR 0.05; P = .021) were independent prognostic factors. Conclusion: For surgical outcome after induction GnP and subsequent CRT for UR-LA PDAC, CA19-9 normalization and maintenance of good nutritional status during treatment until surgery were important for prolonged prognosis.

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.

Gamma-aminobutyric Acid Type A Receptor Subunit Delta as a Potential Therapeutic Target in Gastric Cancer.

BACKGROUND: Novel therapeutic targets are needed to improve the poor prognosis of patients with advanced gastric cancer. The aim of this study was to identify a novel therapeutic target for the treatment of GC and to investigate the potential therapeutic value of an antibody raised against the target. METHODS: We identified gamma-aminobutyric acid type A receptor subunit delta as a candidate therapeutic target by differential transcriptome analysis of metastatic GC tissue and adjacent nontumor tissues. GABRD mRNA levels were analyzed in 230 pairs of gastric tissue by quantitative reverse-transcription polymerase chain reaction. GABRD function was assessed in proliferation, invasion, and apoptosis assays in human GC cell lines expressing control or GABRD-targeting small interfering RNA (siRNA). Mouse anti-human polyclonal GABRD antibodies were generated and assessed for inhibition of GC cell growth in vitro and in a mouse xenograft model of peritoneal GC dissemination. RESULTS: High GABRD mRNA expression level in primary human GC tissue was associated with poor prognosis. Expression of siGABRD in GC cell lines significantly decreased cell proliferation and invasion and increased apoptosis compared with control siRNA expression. Anti-GABRD polyclonal antibodies inhibited GC cell proliferation in vitro and decreased peritoneal tumor nodule size in the mouse xenograft model. CONCLUSION: We identified GABRD as novel regulator of GC cell growth and function. GABRD is upregulated in GC tissue and is associated with poor prognosis, suggesting that it may be a potential therapeutic target for GC.

Synopsis of a clinical practice guideline for pancreatic ductal adenocarcinoma with peritoneal dissemination in Japan; Japan Peritoneal Malignancy Study Group.

Patients with pancreatic ductal adenocarcinoma (PDAC) with peritoneal dissemination have a dismal prognosis because discontinuation of systemic chemotherapy is required for massive ascites or poor performance status. The natural history, diagnosis and treatment of PDAC with peritoneal dissemination have not been fully investigated. We systematically reviewed published information on the clinical diagnosis and treatment of PDAC with peritoneal dissemination using the PubMed database (2000-2020) and provided recommendations in response to clinical questions. This guideline was created according to the "Minds Clinical Practice Guideline Development Guide 2017". The literature quality and body of evidence were evaluated with the GRADE System and classified into four levels ("strong", "medium", "weak", "very weak"). The strength of each final recommendation was decided by a vote of committee members based on the GRADE Grid method. These guidelines address three subjects: diagnostic, chemotherapeutic, and surgical approaches. They include nine clinical questions and statements with recommendation strengths, evidence levels, and agreement rates, in addition to one "column". This is the English synopsis of the 2021 Japanese clinical practice guideline for PDAC with peritoneal dissemination. It summarizes the clinical evidence for the diagnosis and treatment of PDAC with peritoneal dissemination and provides future perspectives.

SLC7A9 as a Potential Biomarker for Lymph Node Metastasis of Esophageal Squamous Cell Carcinoma.

BACKGROUND: The expression of solute carrier (SLC) 7 family genes is reportedly associated with several malignancies. Here, we focused on SLC7A9 and investigated its expression, function, and clinical significance in esophageal squamous cell carcinoma (ESCC). METHODS: SLC7A9 transcription levels were evaluated in 13 ESCC cell lines, and polymerase chain reaction (PCR) array analysis was conducted to detect coordinately expressed genes with SLC7A9. SLC7A9 contributions to proliferation, invasion, and migration were evaluated in ESCC cells subjected to siRNA-mediated gene knockdown and pCMV6-entry plasmid-mediated overexpression. SLC7A9 expression was detected in 189 ESCC tissues by quantitative reverse-transcription (qRT)-PCR and correlated with clinicopathological parameters. RESULTS: The expression levels of SLC7A9 varied widely in ESCC cell lines and correlated with FGFBP1 expression. Knockdown of SLC7A9 significantly suppressed the proliferation, invasion, and migration of the ESCC cell lines. Moreover, overexpression of SLC7A9 enhanced cell proliferation and migration. In analyses of clinical specimens, SLC7A9 mRNA was overexpressed in the ESCC tissues compared with the adjacent normal esophageal tissues. High mRNA expression was significantly associated with high levels of squamous cell carcinoma-related antigen and carcinoembryonic antigen, advanced disease stage, and lymph node metastasis. High SLC7A9 expression was also significantly associated with poor disease-specific and disease-free survival, and lymph node recurrence after radical surgery, but not with the other recurrence patterns. On multivariate analysis, high SLC7A9 expression was an independent predictor of lymph node recurrence. CONCLUSIONS: SLC7A9 influences the malignant behavior of ESCC cells. Tumor SLC7A9 expression may serve as a novel biomarker for predicting lymph node metastasis and recurrence in ESCC patients.

Paratracheal air cyst and bronchogenic cyst in patients with esophageal cancer who received thoracoscopic esophagectomy: A case series of three patients.

INTRODUCTION AND IMPORTANCE: Mediastinal cystic lesions, such as paratracheal air cyst (PTAC) and bronchogenic cyst (BC), are rare anomaly usually found incidentally in thoracic imaging. Special attention is needed in the case of thoracic surgery. CASE PRESENTATION: All three patients were male, 71, 73, and 76 years old. Preoperative CT showed each had a lobular cystic lesion at the right posterolateral side of trachea in the thoracic outlet 11, 14, and 19 mm in size, respectively, with air density and tracheal communication, leading to a diagnosis of PTACs. An oval cystic lesion, 7 mm in size, was found in one patient at the right lateral side of the upper esophagus with low density and without tracheal communication, leading to a diagnosis of paraesophageal BC. Intraoperative findings of the three PTACs demonstrated a soft bulge from the membranous portion of trachea that was left intact. The BC had an oval elastic structure, mimicking a metastatic lymph node, and was removed with the mediastinal lymph nodes. Histological examination showed ciliated columnar epithelium, confirming a diagnosis of BC. CLINICAL DISCUSSION: PTACs are associated with increased intraluminal pressure due to chronic lung disease. BCs are congenital anomalies that originate from abnormal budding of the embryonic foregut. CONCLUSION: PTACs and BCs need to be considered in preoperative image diagnosis in patients with esophageal cancer. PTACs should be left intact to avoid tracheal injury, while removal of isolated BCs is recommended as a diagnostic and therapeutic measure.

Distal partial gastrectomy for gastric tube cancer with intraoperative blood flow evaluation using indocyanine green fluorescence.

With recent advances in the treatment of esophageal cancer and long-term survival after esophagectomy, the number of gastric tube cancer (GTC) has been increasing. Total gastric tube resection with lymph node dissection is considered to be a radical treatment, but it causes high post-operative morbidity and mortality. We report an elderly patient with co-morbidities who developed pyloric obstruction due to GTC after esophagectomy with retrosternal reconstruction. The patient was treated using distal partial gastric tube resection (PGTR) and Roux-en-Y reconstruction with preservation of the right gastroepiploic artery and right gastric artery. Intraoperative blood flow visualization using indocyanine green (ICG) fluorescence demonstrated an irregular demarcation line at the distal side of the preserved gastric tube, indicating a safe surgical margin to completely remove the ischemic area. PGTR with intraoperative ICG evaluation of blood supply in the preserved gastric tube is a safe and less-invasive surgical option in patients with poor physiological condition.

Optimal Preoperative Multidisciplinary Treatment in Borderline Resectable Pancreatic Cancer.

Background: The objective of this study was to investigate the optimal neoadjuvant therapy (NAT) for borderline resectable pancreatic cancer invading the portal vein (BR-PV) or abutting major arteries (BR-A). Methods: We retrospectively analyzed 88 patients with BR-PV and 111 patients with BR-A. Results: In BR-PV patients who underwent upfront surgery (n = 46)/NAT (n = 42), survival was significantly better in the NAT group (3-year overall survival (OS): 5.8%/35.5%, p = 0.004). In BR-A patients who underwent upfront surgery (n = 48)/NAT (n = 63), survival was also significantly better in the NAT group (3-year OS:15.5%/41.7%, p < 0.001). The prognosis tended to be better in patients who received newer chemotherapeutic regimens, such as FOLFIRINOX and gemcitabine with nab-paclitaxel. In 36 BR-PV patients who underwent surgery after NAT, univariate analysis revealed that normalization of tumor marker (TM) levels (p = 0.028) and preoperative high prognostic nutritional index (PNI) (p = 0.022) were significantly associated with a favorable prognosis. In 39 BR-A patients who underwent surgery after NAT, multivariate analysis revealed that preoperative PNI > 42.5 was an independent prognostic factor (HR: 0.15, p = 0.014). Conclusions: NAT using newer chemotherapy is essential for improving the prognosis of BR pancreatic cancer. These findings suggest that prognosis may be prolonged by maintaining good nutritional status during preoperative treatment.

Early ambulation after general and digestive surgery: a retrospective single-center study.

PURPOSE: Postoperative early ambulation contributes to the improvement of postoperative outcomes; however, the definition of "early" ambulation is unclear. In this study, we aimed to define desirable "early" ambulation after digestive surgery in terms of short-term outcomes and to identify the risk factors for delayed ambulation. METHODS: We retrospectively analyzed 718 patients who underwent major digestive surgery between January 2016 and May 2019 in our hospital. The timing of first ambulation after surgery was reviewed and correlated with short-term postoperative outcomes and perioperative patient characteristics. RESULTS: Of 718 patients, 55% underwent first ambulation at postoperative day (POD) 1, 31% at POD 2, and the remaining patients at POD 3 or later. Whereas short-term outcomes were equivalent among patients with first ambulation at POD 1 and those at POD 2, patients who delayed ambulation until POD 3 or after had an increased incidence of infectious complications (P = 0.004), longer hospitalization (P < 0.001), and a decreased home discharge rate (P < 0.001). Multivariate analysis showed that significant predictors of delayed ambulation (POD ≥ 3) were poor Eastern Cooperative Oncology Group performance status (ECOG-PS), low controlling nutritional status (CONUT), nonlaparoscopic surgery, and transvenous opioid use. Of these factors, the combination of ECOG-PS, CONUT, and nonlaparoscopic surgery clearly stratified patients into four-grade risk groups regarding delayed ambulation (P for trend < 0.001). CONCLUSION: Our results suggest that first ambulation before POD 2 could be desirable for better short-term outcomes. Active preoperative intervention, such as nutritional care and prehabilitation, in patients with multiple risk factors for delayed ambulation could improve the postoperative course.

Chromobox 2 Expression Predicts Prognosis After Curative Resection of Oesophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: To investigate the function of chromobox 2 (CBX2) in oesophageal squamous cell carcinoma (OSCC). MATERIALS AND METHODS: We used real-time quantitative reverse transcription PCR (qRT-PCR) and immunohistochemistry to determine CBX2 expression levels in 13 human OSCC cell lines and clinical specimens of two independent cohorts of patients with OSCC. RESULTS: PCR array analysis revealed that CBX2 was co-ordinately expressed with WNT5B in OSCC cell lines. RT-qPCR analysis of clinical samples revealed a high tumour-specific CBX2 expression compared with normal oesophageal tissues. High CBX2 expression was significantly associated with shorter disease-specific survival, hematogenous recurrence, and overall recurrence. Analysis of tissue microarrays of one cohort revealed that patients with higher CBX2 levels tended to have a shorter disease-specific survival. CONCLUSION: CBX2 overexpression in OSCC tissues may serve as a novel biomarker for predicting survival and hematogenous recurrence.

Expression and Malignant Potential of B4GALNT4 in Esophageal Squamous Cell Carcinoma.

BACKGROUND: ß-1,4-N-Acetyl-galactosaminyltransferase 4 (B4GALNT4), an enzyme involved in ganglioside synthesis, is upregulated in many cancers. We examine B4GALNT4 expression and its relationship to prognosis in esophageal squamous cell carcinoma (ESCC). PATIENTS AND METHODS: Expression of B4GALNT4 mRNA and B4GALNT4 protein was analyzed by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry, respectively, in 17 human ESCC cell lines and/or clinical specimens from two independent cohorts of 147 and 159 ESCC patients. The contributions of B4GALNT4 to proliferation, invasion, migration, and adhesion was evaluated in ESCC cells subjected to siRNA-mediated gene knockdown. Correlations between clinicopathological parameters and B4GALNT4 expression in clinical specimens were analyzed in both patient cohorts. RESULTS: B4GALNT4 mRNA expression levels varied widely in ESCC cell lines, regardless of differentiation status or the originating tissue. Knockdown of B4GALNT4 significantly suppressed the proliferation, invasion, migration, and adhesion of ESCC cell lines compared with control cells. B4GALNT4 mRNA was overexpressed in ESCC tissues compared with adjacent normal esophageal tissues. High mRNA expression was significantly associated with poor disease-free survival and hematogenous recurrence, and high B4GALNT4 protein expression was also significantly related to poor disease-specific survival. On multivariable analysis, high B4GALNT4 expression was an independent predictor of poor prognosis. In both patient cohorts, high B4GALNT4 expression did not correlate with known prognostic factors, such as disease stage, lymphovascular invasion, or squamous cell-carcinoma-related antigen level. CONCLUSIONS: B4GALNT4 influences the malignant behavior of ESCC cells. B4GALNT4 expression may serve as a novel prognostic marker, independent of established risk factors, for ESCC patients.

Risk factors for postoperative pneumonia after general and digestive surgery: a retrospective single-center study.

PURPOSE: Pneumonia is the second-most common complication in postoperative patients and is associated with significant morbidity and high costs of care. We aimed to determine the risk factors for pneumonia after general and digestive surgery. METHODS: The medical records of 1,016 patients who underwent general and digestive surgery between January 2016 and March 2019 in our hospital were reviewed. RESULTS: Of the 1,016 patients, 67 (6.6%) developed postoperative pneumonia. The multivariate analysis showed that significant predictors of postoperative pneumonia were a poor Eastern Cooperative Oncology Group performance status (ECOG-PS), low forced vital capacity and low forced expiratory volume in one second in the spirometry test, malnutrition (low serum albumin levels and low controlling nutritional status scores and prognostic nutritional index [PNI] values), esophagectomy, upper gastrointestinal surgery, and nonlaparoscopic surgery. Of these factors, the combination of PNI and ECOG-PS clearly stratified patients into low-, intermediate-, and high-risk groups with respect to developing postoperative pneumonia (area under the curve: 0.709). CONCLUSIONS: Although postoperative pneumonia is associated with many clinical variables, active medical intervention for the prevention of pneumonia in patients with multiple risk factors can improve the postoperative course. In particular, perioperative nutritional care may prevent postoperative pneumonia in patients with malnutrition and a poor PS.

PRAME as a Potential Biomarker for Liver Metastasis of Gastric Cancer.

BACKGROUND: Liver metastasis of gastric cancer (GC) is highly associated with poor prognosis. The development of sensitive biomarkers for detecting and predicting liver metastasis is required for better clinical outcome. OBJECTIVE: In this study, we aimed to identify novel genes associated with liver metastasis of GC. METHODS: Global expression profiling of 57,749 genes was performed using surgically resected gastric tissues from four patients with liver metastasis to identify candidate genes. The mRNA expression levels of the selected candidate gene were analyzed in the resected gastric tissues of 300 GC patients and correlated with clinicopathological parameters. Fourteen GC cell lines were subjected to mRNA expression and polymerase chain reaction (PCR) array analysis. RESULTS: Among 25 candidate genes identified by transcriptome analysis, preferentially expressed antigen of melanoma (PRAME) was selected for subsequent analyses. mRNA expression analysis of clinical samples revealed the aberrant expression of PRAME in GC tissues, and its high expression was significantly related to differentiated phenotype and vessel invasion, as well as liver metastasis. High PRAME expression was significantly associated with hepatic recurrence after curative surgery, and cumulative incidences of hepatic recurrence were significantly greater in patients with high PRAME expression compared with patients with low PRAME expression. In an in vitro analysis, overexpression was observed in all GC cell lines compared with a normal epithelial cell line. PCR array analysis revealed the coordinate expression of MMP9, OCLN, IL1RN, and MST1R. CONCLUSIONS: PRAME is related to the malignant potential of GC and could serve as a novel biomarker for the detection and prediction of liver metastasis.

PRAME Expression as a Potential Biomarker for Hematogenous Recurrence of Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: To investigate the function of preferentially expressed antigen of melanoma (PRAME) in esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: mRNA expression levels of PRAME were analyzed in resected esophageal tissues of 150 ESCC patients and correlated with clinicopathological parameters. We also investigated the potential function of PRAME by analyzing coordinately expressed genes in 13 ESCC cell lines. RESULTS: RT-qPCR analysis of clinical samples revealed aberrantly high PRAME expression in tumors compared with normal esophageal tissues. High PRAME expression was significantly associated with shorter disease-specific survival and hematogenous recurrence, but not with overall recurrence. The cumulative incidence of hematogenous recurrence was significantly greater for patients with high compared to those with low PRAME expression. In vitro, PCR array analysis revealed that PRAME was coordinately expressed with EGFR, ITGB, and TCF3. CONCLUSION: PRAME is overexpressed in ESCC tissues and may serve as a novel biomarker for predicting hematogenous recurrence.