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

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

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

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

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

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

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

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

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

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

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

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

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

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

Identification of stromal cell-derived factor 4 as a liquid biopsy-based diagnostic marker in solid cancers.

There is a need for serum diagnostic biomarkers to improve the prognosis of solid malignant tumors. Here, we conducted a single-institutional study to evaluate the diagnostic performance of serum stromal cell-derived factor 4 (SDF4) levels in cancer patients. Serum samples were collected from a total of 582 patients with solid cancers including gastric cancer (GC) and 80 healthy volunteers. SDF4 protein levels in sera, and conditioned media or lysates of human GC cell lines were measured by enzyme-linked immunosorbent assay, and those in GC tissue by immunohistochemistry. Serum SDF4 levels were higher in patients with cancer than the healthy control in all cancer type. Regarding GC, serum SDF4 levels distinguished healthy controls from GC patients with the area under the curve value of 0.973, sensitivity of 89%, and specificity of 99%. Serum SDF4 levels were significantly elevated in patient with early stage GC. In immunohistochemistry, the frequency of SDF4-positive GC tumors did not vary significantly between GC stages. The ability of human GC cell lines to both produce and secrete SDF4 was confirmed in vitro. In conclusion, serum SDF4 levels could be a promising candidate for a novel diagnostic biomarker for GC and other malignancies.

High Preoperative Serum D-dimer Predicts Unfavorable Survival Outcomes for Pancreatic Cancer Patients.

BACKGROUND/AIM: Pancreatic cancer cells release certain tissue factors into the bloodstream. It is well known that pancreatic cancer progresses with thrombus formation. Because we routinely measure serum D-dimer levels in preoperative patients as a screening marker of deep venous thrombosis, we examined its association with high serum D-dimer in our cohort of pancreatic cancer resected cases. PATIENTS AND METHODS: We examined 315 patients with pancreatic ductal adenocarcinoma who underwent surgical resection in our department from January 2012 to July 2021. All cases were divided into high D-dimer cases (n=118) and low D-dimer cases (n=197) using the cut-off value of 1.0 µg/ml, an institutional upper limit. Clinicohistological characteristics and postoperative survival outcomes were evaluated. RESULTS: Preoperative high D-dimer cases showed significantly worse progression-free survival (PFS) (p=0.021) and overall survival (OS) (p=0.027) than low D-dimer cases; median PFS was 13.9 months versus 21.4 months, and that of OS was 33.4 months versus 68.0 months. Clinicohistological characteristics of high D-dimer cases were age over 70 years (p<0.001), pathological portal vein invasion (p=0.003), and initially borderline resectable or unresectable cases (p=0.027). Multivariate analysis indicated that preoperative high D-dimer was a significant prognostic factor of PFS (hazard ratio=1.42, p=0.025) and OS (hazard ratio=1.51, p=0.036). CONCLUSION: Preoperative high serum D-dimer over 1.0 µg/ml was associated with pathological portal vein invasion and could be an unfavorable prognostic marker of PFS and OS after surgery, typically due to distant metastasis.

Albumin-Globulin Ratio Indicates the Survival Outcome of Pancreatic Cancer Cases Who Underwent Preoperative Treatment and Curative Surgical Resection.

BACKGROUND: The pretreatment albumin-globulin ratio (AGR) is a frequently used inflammation-associated factor that has been reported to have associations with the survival outcomes of various malignancies. METHODS: We retrospectively analyzed 162 patients with pancreatic cancer who underwent preoperative treatment followed by curative surgery at Nagoya University Hospital between April 2010 and December 2020. Representative nutritional status indicators of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), prognostic nutritional index (PNI), and albumin-globulin ratio (AGR) were calculated for each case. RESULTS: Among pretreatment blood examination parameters, only AGR (cutoff: 1.33) showed a significant difference in overall survival time (OS) and progression-free survival time (PFS) from the beginning of the preoperative treatment. Median PFS was 22.3 mo, in high AGR cases and 17.1 mo, in low AGR cases (P = 0.019). Median OS was 48.7 mo, in high AGR cases and 32.9 mo, in low AGR cases (P = 0.043). CONCLUSION: High pretreatment AGR may be a favorable prognostic factor for pancreatic cancer patients who received preoperative multimodal therapy followed by curative cancer resection. It may imply that nutritional status and inflammation control before the multimodal treatment affect the survival outcomes of pancreatic cancer cases and needs to be optimized.

The effects of ustekinumab on small intestinal lesions and stenotic lesions.

Crohn's disease patients suffer from symptoms originating from small bowel lesions, including strictures. As many of these patients also have a potential risk of surgery, it is important to consider various therapeutic strategies for small bowel lesions. We retrospectively analyzed the therapeutic effects of ustekinumab, interleukin-12 and -23 blocker, for small intestinal lesions and intestinal stenosis in order to contribute to the optimal management of Crohn's disease. Patients who underwent total colonoscopy or small bowel endoscopy before and after the introduction of ustekinumab were enrolled in this study. The colonoscopy findings were evaluated by the simple endoscopic score for Crohn's disease, and small bowel endoscopy findings were evaluated using the modified simple endoscopic score for Crohn's disease. Endoscopic scores were compared before and after the introduction of ustekinumab and between the responders and non-responders to ustekinumab. Responders were defined as those whose Crohn's disease activity index score at 24 weeks fell below 150 points, or those whose score decreased by more than 100 points from the pre-induction level. A total of 50 patients were enrolled in the study, and the number of responders was 35. Pre-induction simple endoscopic scores were lower for responders, but no significant difference was observed in the modified simple endoscopic scores. The total decrease in the endoscopic score was significantly higher in the responders for both the small and large intestine. Use of ustekinumab as a first-line treatment for patients with small bowel lesions or stricture-prone lesions may be a new treatment consideration in the future.

Lysosomal-associated membrane protein family member 5 promotes the metastatic potential of gastric cancer cells.

BACKGROUND: Metastatic gastric cancer (GC) has a poor prognosis, and elucidating the molecular mechanisms involved in metastasis may lead to the development of novel therapeutic modalities. METHODS: Transcriptome analysis of surgically resected metastatic tissue from GC patients and noncancerous tissue was performed to identify novel metastasis-related genes. Analyses of in vitro cell function, apoptosis, the cell cycle and cancer stemness were performed using GC cell lines with a stable knockout of a candidate gene. In vivo percutaneous, peritoneal dissemination and liver metastasis xenograft models were also generated. PCR array and proteome analyses were performed. Expression of the candidate gene was analyzed in GC tissues from 300 patients. RESULTS: Lysosomal Associated Membrane Protein Family Member 5 (LAMP5) was upregulated in the metastatic tissues. LAMP5 knockout significantly suppressed proliferation, invasion, and migration of GC cells and increased apoptosis, cell cycle arrest and cancer stemness. LAMP5 knockout virtually suppressed tumor growth in in vivo percutaneous, peritoneal dissemination and liver metastasis models. EMT- and autophagy-related genes were associated with LAMP5. High LAMP5 mRNA levels were significantly associated with a worse prognosis. CONCLUSION: LAMP5 plays a vital role in metastasis formation and may be a promising novel target of drug development for metastatic GC in the future.

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.

Randomised phase II trial of capecitabine plus oxaliplatin with continuous versus intermittent use of oxaliplatin as adjuvant chemotherapy for stage II/III colon cancer (CCOG-1302 study).

BACKGROUND: Peripheral sensory neuropathy (PSN) caused by oxaliplatin-based adjuvant chemotherapy adversely affects patients' quality of life. This study evaluated the efficacy and safety of capecitabine plus oxaliplatin (CAPOX) with intermittent oxaliplatin use compared with the standard CAPOX in adjuvant therapy for colon cancer. PATIENTS AND METHODS: Patients with curative resection for stage II/III colon cancer were randomly assigned to receive either CAPOX with continuous oxaliplatin (eight cycles of CAPOX) or CAPOX with intermittent oxaliplatin (two cycles of CAPOX, four cycles of capecitabine and two cycles of CAPOX). The primary end-point was the 1-year PSN rate, and the key secondary end-point was disease-free survival (DFS). RESULTS: Two hundred patients were enrolled in the intent-to-treat population. After 4 patients withdrew, 196 patients were included in the safety analysis. The overall treatment completion rate was 65% for continuous vs. 89% for intermittent treatment (p < 0.001). The 1-year PSN rate was 60% (95% confidence interval [CI], 50%-70%) for continuous and 16% (95% CI, 10%-25%) for intermittent treatment (p < 0.001). After a median follow-up of 52 months, 40 events (20%) were observed. The 3-year DFS was 81% (95% CI, 71%-87%) for continuous and 84% (95% CI, 75%-90%) for intermittent treatment (hazard ratio [HR], 0.87; 95% CI, 0.47-1.63). Among patients with high-risk disease (T4 or N2-3), the 3-year DFS was 57% for continuous vs. 74% for intermittent treatment (HR, 0.66). CONCLUSION: CAPOX with planned intermittent oxaliplatin may be feasible as an adjuvant therapy for colon cancer and substantially reduce the duration of long-lasting PSN. TRIAL IDENTIFIER: UMIN000012535.

Short-term outcomes of gastrectomy after neoadjuvant chemotherapy for clinical stage III gastric cancer: propensity score-matched analysis of a multi-institutional database.

PURPOSE: Preoperative chemotherapy for gastric cancer may be effective from the standpoint of compliance, although there is insufficient evidence of its efficacy. We analyzed a multicenter database to clarify whether preoperative chemotherapy influenced the short-term outcomes of gastrectomy. METHODS: We analyzed, retrospectively, 3571 patients who underwent gastrectomy between January, 2010 and December, 2014. Patients with clinical stage-III gastric adenocarcinoma were divided into a neoadjuvant chemotherapy (NAC) group and a non-NAC group. We performed propensity-matched comparative analysis to stratify the groups according to age, sex, tumor region, tumor type, preoperative stage, procedure, lymph node dissection, and tumor differentiation. Preoperative blood data, surgical findings, and postoperative complications were analyzed. RESULTS: Analysis of the matched NAC (n = 64) and non-NAC (n = 128) groups revealed that the preoperative values of neutrophils, platelets, and Hb were significantly lower in the NAC group. Blood loss during surgery was significantly higher, surgical times were longer, and the rate of repeat surgery was significantly lower in the NAC group; however, the rates of rehospitalization did not differ between the groups and mortality was 0% in both groups. Postoperative complications were not significantly different between the groups. CONCLUSIONS: NAC did not increase the complication rate of gastrectomy for gastric cancer.

Amido-Bridged Nucleic Acid-Modified Antisense Oligonucleotides Targeting SYT13 to Treat Peritoneal Metastasis of Gastric Cancer.

Patients with peritoneal metastasis of gastric cancer have dismal prognosis, mainly because of inefficient systemic delivery of drugs to peritoneal tumors. We aimed to develop an intraperitoneal treatment strategy using amido-bridged nucleic acid (AmNA)-modified antisense oligonucleotides (ASOs) targeting synaptotagmin XIII (SYT13) and to identify the function of SYT13 in gastric cancer cells. We screened 71 candidate oligonucleotide sequences according to SYT13-knockdown efficacy, in vitro activity, and off-target effects. We evaluated the effects of SYT13 knockdown on cellular functions and signaling pathways, as well as the effects of intraperitoneal administration to mice of AmNA-modified anti-SYT13 ASOs. We selected the ASOs (designated hSYT13-4378 and hSYT13-4733) with the highest knockdown efficiencies and lowest off-target effects and determined their abilities to inhibit cellular functions associated with the metastatic potential of gastric cancer cells. We found that SYT13 interfered with focal adhesion kinase (FAK)-mediated intracellular signals. Intraperitoneal administration of hSYT13-4378 and hSYT13-4733 in a mouse xenograft model of metastasis inhibited the formation of peritoneal nodules and significantly increased survival. Reversible, dose- and sequence-dependent liver damage was induced by ASO treatment without causing abnormal morphological and histological changes in the brain. Intra-abdominal administration of AmNA-modified anti-SYT13 ASOs represents a promising strategy for treating peritoneal metastasis of gastric cancer.

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.