Dual-modified antisense oligonucleotides targeting oncogenic protocadherin to treat gastric cancer.

BACKGROUND: The objective of this study was to develop an innovative treatment strategy utilizing antisense oligonucleotides (ASOs) that target the gene encoding protocadherin alpha 11 (PCDHA11) and to elucidate the role of PCDHA11 in gastric cancer cells. METHODS: We designed and screened 54 amido-bridged nucleic acid (AmNA)-modified ASOs, selecting them based on PCDHA11-knockdown efficacy, in vitro and in vivo activity, and off-target effects. We assessed the impact of AmNA-modified anti-PCDHA11 ASOs on cellular functions and signaling pathways, and investigated the effects of Pcdha11 deficiency in mice. RESULTS: AmNA-modified anti-PCDHA11 ASOs significantly reduced the proliferation of gastric cancer cells and other solid tumors, whereas overexpression of PCDHA11 enhanced cell proliferation. The selected ASOs inhibited cellular functions related to the metastatic potential of gastric cancer cells, including migration, invasiveness, spheroid formation, and cancer stemness. Our findings revealed that AmNA-modified anti-PCDHA11 ASOs disrupted the AKT/mTOR, Wnt/ß-catenin, and JAK/STAT signaling pathways. In mouse models of peritoneal metastasis (gastric and pancreatic cancer), systemic metastasis, and established subcutaneous tumors, administration of AmNA-modified anti-PCDHA11 ASOs inhibited tumor growth. ASO treatment induced reversible, dose- and sequence-dependent liver damage. Pcdha11-deficient mice demonstrated normal reproductive, organ, and motor functions. CONCLUSIONS: AmNA-modified anti-PCDHA11 ASOs offer a promising therapeutic strategy for the treatment of gastric cancer and other solid malignancies.

Oncological similarities between large type 3 and type 4 tumors in patients with resectable gastric cancer: a propensity score-matched analysis of a multi-institutional dataset.

BACKGROUND: Large type 3 (diameter ≥ 8 cm) and type 4 gastric cancers have been arbitrarily combined in Japan as a single entity. However, whether these two types are oncologically similar remain unclear. This study aimed to clarify this issue. METHODS: In this retrospective study, we analyzed a database of 3,575 patients from nine institutions who underwent gastrectomy between 2010 and 2014. Using propensity scores to balance significant variables, we compared prognoses and tumor recurrences. RESULTS: Of patients with clinical T3/T4 who underwent R0 resection, 75 and 73 had large type 3 and 4 tumors, respectively. Patients with type 4 tumors had significantly lower overall survival rates than those of patients with large type 3 tumors (hazard ratio [HR] 1.77; 95% confidence interval [CI] 1.14-2.74). However, among the large type 3 tumors, a remarkable difference in prognosis was observed between the differentiated and undifferentiated histological types. A comparison was made between large type 3 with undifferentiated phenotype and type 4, each with 39 patients after propensity score matching. Outcomes in both groups were similar in terms of overall survival (HR 1.28; 95% CI 0.73-2.25) and relapse-free survival (HR 1.34; 95% CI 0.80-2.27). No statistically significant differences were observed in the incidence of peritoneal recurrence (35.9% vs. 46.1%, P = 0.36) and lymph node recurrence (25.6% vs. 12.8%, P = 0.15). CONCLUSIONS: Large type 3 tumors with undifferentiated phenotype and type 4 tumors were oncologically similar. This subgroup could be considered as a new entity for future clinical trials.

The perspective for next-generation lung replacement therapies: functional whole lung generation by blastocyst complementation.

PURPOSE OF REVIEW: Blastocyst complementation represents a promising frontier in next-generation lung replacement therapies. This review aims to elucidate the future prospects of lung blastocyst complementation within clinical settings, summarizing the latest studies on generating functional lungs through this technique. It also explores and discusses host animal selection relevant to interspecific chimera formation, a challenge integral to creating functional human lungs via blastocyst complementation. RECENT FINDINGS: Various gene mutations have been utilized to create vacant lung niches, enhancing the efficacy of donor cell contribution to the complemented lungs in rodent models. By controlling the lineage to induce gene mutations, chimerism in both the lung epithelium and mesenchyme has been improved. Interspecific blastocyst complementation underscores the complexity of developmental programs across species, with several genes identified that enhance chimera formation between humans and other mammals. SUMMARY: While functional lungs have been generated via intraspecies blastocyst complementation, the generation of functional interspecific lungs remains unrealized. Addressing the challenges of controlling the host lung niche and selecting host animals relevant to interspecific barriers between donor human and host cells is critical to enabling the generation of functional humanized or entire human lungs in large animals.

Outcomes of surgical treatment for enterovesical fistula in Crohn's disease.

Enterovesical fistula (EVF) in Crohn's disease (CD) often does not improve with medical treatment and requires surgical treatment. The surgical treatment strategy for EVF in CD is definitive resection of the intestinal tract side, and performing a leak test using dye injection into the bladder after EVF dissection to determine the appropriate surgical procedure for the bladder side. This study aimed to evaluate the outcomes of surgical treatment for EVF in CD. Twenty-one patients who underwent surgery for EVF between 2006 and 2021 were included and retrospectively evaluated for clinical background, surgical procedures, and postoperative complications. The most common origin of EVF was the ileum (17 cases; 81%), and the most common site of EVF formation was the apex (12; 57%). Surgical approaches were laparotomy in 11 (52%) cases and laparoscopy in 10 (48%). Surgical procedures on the bladder side were fistula dissection in 13 (62%) cases and sutured closure of fistula in 8 (38%). A comparison of approaches revealed no significant difference in operative time, but the amount of blood loss was significantly less in the laparoscopy (p < 0.01). There was no significant difference in the occurrence of postoperative complications between approaches. Postoperative anti-TNF-α antibody agents were used in 17 (81%) cases, and there were no cases of recurrent EVF. In conclusion, definitive resection of the intestinal tract and minimal treatment on the bladder side were sufficient to achieve satisfactory outcomes for EVF in CD.

Ephrin Forward Signaling Controls Interspecies Cell Competition in Pluripotent Stem Cells.

In the animal kingdom, evolutionarily conserved mechanisms known as cell competition eliminate unfit cells during development. Interestingly, cell competition also leads to apoptosis of donor cells upon direct contact with host cells from a different species during interspecies chimera formation. The mechanisms underlying how host animal cells recognize and transmit cell death signals to adjacent xenogeneic human cells remain incompletely understood. In this study, we developed an interspecies cell contact reporter system to dissect the mechanisms underlying competitive interactions between mouse and human pluripotent stem cells (PSCs). Through single-cell RNA-seq analyses, we discovered that Ephrin A ligands in mouse cells play a crucial role in signaling cell death to adjacent human cells that express EPHA receptors during interspecies PSC co-culture. We also demonstrated that blocking the Ephrin A-EPHA receptor interaction pharmacologically, and inhibiting Ephrin forward signaling genetically in the mouse cells, enhances the survival of human PSCs and promotes chimera formation both in vitro and in vivo . Our findings elucidate key mechanisms of interspecies PSC competition during early embryogenesis and open new avenues for generating humanized tissues or organs in animals, potentially revolutionizing regenerative medicine.

Generation of salivary glands derived from pluripotent stem cells via conditional blastocyst complementation.

Whole salivary gland generation and transplantation offer potential therapies for salivary gland dysfunction. However, the specific lineage required to engineer complete salivary glands has remained elusive. In this study, we identify the Foxa2 lineage as a critical lineage for salivary gland development through conditional blastocyst complementation (CBC). Foxa2 lineage marking begins at the boundary between the endodermal and ectodermal regions of the oral epithelium before the formation of the primordial salivary gland, thereby labeling the entire gland. Ablation of Fgfr2 within the Foxa2 lineage in mice leads to salivary gland agenesis. We reversed this phenotype by injecting donor pluripotent stem cells into the mouse blastocysts, resulting in mice that survived to adulthood with salivary glands of normal size, comparable to those of their littermate controls. These findings demonstrate that CBC-based salivary gland regeneration serves as a foundational experimental approach for future advanced cell-based therapies.

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.

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.

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.

Protocol of a phase II study investigating the efficacy and safety of trifluridine/tipiracil plus ramucirumab as a third-line or later treatment for advanced gastric cancer.

In Japan, systemic chemotherapy is the standard treatment for unresectable, advanced, or recurrent gastric cancer. However, numerous patients with gastric cancer do not receive late-line treatment because of the rapid progression of gastric cancer. Additionally, late-line treatments, such as nivolumab, trifluridine tipiracil (FTD/TPI), or irinotecan, have limited effects on improving clinical symptoms and delaying the onset of symptoms associated with cancer progression. Recently, a combination of FTD/TPI and ramucirumab was reported to have a high response rate in late-line treatment; however, owing to patient selection bias and a high rate of hematologic toxicity in that previous study, this regimen may not be feasible in real-world clinical applications. Our objective is to conduct a single-arm phase II study to assess the safety and efficacy of FTD/TPI plus ramucirumab combination therapy for gastric cancer after third-line treatment under real-world clinical conditions. This study will recruit 32 patients according to eligibility criteria and administer FTD/TPI (35 mg/m2) and intravenous ramucirumab (8 mg/kg). The primary endpoint will be the time to treatment failure. The secondary endpoints will include the overall survival time, progression-free survival time, overall response rate, disease control rate, relative dose intensity, and incidence of adverse events. The results will add new insights for improving the late-line treatment of advanced gastric cancer.

Docetaxel, cisplatin, and fluorouracil with pegfilgrastim on day 3 as neoadjuvant chemotherapy for esophageal cancer.

PURPOSE: A high risk of febrile neutropenia (FN) from neoadjuvant chemotherapy with docetaxel, cisplatin, and fluorouracil (DCF) for esophageal cancer has been reported. The optimal timing of prophylactic use of pegfilgrastim remains to be elucidated. To evaluate the effect of pegfilgrastim administered on day 3, we conducted a feasibility study. METHODS: Chemotherapy consisted of intravenous administration of docetaxel (70 mg/m2 per day) and cisplatin (70 mg/m2 per day) on day 1 and continuous infusion of 5-fluorouracil (750 mg/m2 per day) on days 1-5. Pegfilgrastim was given as a single subcutaneous injection at a dose of 3.6 mg on day 3 during each treatment course. This regimen was repeated every 3 weeks for up to a maximum of three courses. Prophylactic antibiotics were not needed but were allowed to be given at the discretion of the physician. The primary endpoint was the incidence of FN. RESULTS: Twenty-six patients were administered DCF in combination with pegfilgrastim on day 3. After the first course of DCF, 10 out of 26 patients (38.5%) experienced grade 4 neutropenia, and two patients (7.7%) experienced FN. Of the 14 patients who did not receive prophylactic antibiotics, four had grade 4 neutropenia, including two who developed FN. On the contrary, of the 12 patients who received prophylactic levofloxacin, six had grade 4 neutropenia, but no cases of FN were observed. CONCLUSION: Administration of pegfilgrastim on day 3 was not sufficient to prevent FN due to DCF treatment, and prophylactic administration of both pegfilgrastim and antibiotics could be a solution.

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.

A computational method for a thermoacoustic boundary layer in a gas-filled tube.

This paper demonstrates a computational method to solve equations for a thermoacoustic boundary layer in a gas-filled tube subjected to a temperature gradient axially. With applications to numerical simulations of thermoacoustic systems, the purpose is to establish a method to evaluate numerically a velocity vb at the edge of a boundary layer directed into a core region in the outside of the layer. The computational method exploits a series expansion in terms of Chebyshev polynomials. Solved is a benchmark example for which analytical solutions are available. Assuming that a quiescent gas is started by an impulse and an acoustic field in the core region is given, an axial velocity and a temperature disturbance in the boundary layer are sought, from which vb is derived. Comparing the numerical solutions obtained against the analytical ones, it is found that the acoustic field and ultimately vb are well obtained with good accuracy. It is thus concluded that the present computational method will apply to numerical simulations based on the boundary-layer theory.

Genetic polymorphisms as predictive biomarkers of adverse events during preoperative chemotherapy in esophageal cancer.

PURPOSE: This study aimed to explore associations between genetic polymorphisms and adverse effects due to preoperative chemotherapy with docetaxel, cisplatin, and fluorouracil (DCF) for esophageal cancer. METHODS: Preoperative DCF (docetaxel, 70 mg/m2/day, day 1; cisplatin, 70 mg/m2/day, day 1; fluorouracil, 750 mg/m2/day, days 1-5) was repeated every 3 weeks for up to three cycles. Genotyping of nine candidate genetic polymorphisms was conducted using blood samples from the enrolled patients. RESULTS: According to a multivariable analysis evaluating 50 patients, grade 3 or worse neutropenia was more likely to occur in those with the ABCC2-24C/T or T/T genotype (rs717620) (OR, 5.30, P = 0.013). Additionally, patients with the TYMS 3'-UTR 0 bp/0 bp genotype (rs151264360) showed a trend toward grade 3 or worse hyponatremia (OR, 0.16, P = 0.005). Grade 2 or worse thrombocytopenia was more likely to occur in patients with the TNF-α-1031C/T or T/T genotype (rs1799964) (OR, 6.30, P = 0.016) and IL-6-634C/C genotype (rs1800796) (OR, 0.18, P = 0.034), and grade 2 or worse anemia was more likely to occur in patients with the MCP-1-2518G/G genotype (rs1024611) (OR, 0.19, P = 0.027). CONCLUSIONS: ABCC2-24C > T (rs717620), TYMS 3'-UTR 6-bp indel (rs151264360), TNF-α-1031T > C (rs1799964) as well as IL-6-634G > C (rs1800796), and MCP-1-2518A > G (rs1024611) polymorphisms might serve as independent and predictive biomarkers for neutropenia, hyponatremia, thrombocytopenia, and anemia, respectively, during preoperative chemotherapy with docetaxel, cisplatin, and fluorouracil for patients with esophageal cancer.

In vivo lung perfusion for prompt recovery from primary graft dysfunction after lung transplantation.

BACKGROUND: No proven treatment after the development of primary graft dysfunction (PGD) is currently available. Here, we established a novel strategy of in vivo lung perfusion (IVLP) for the treatment of PGD. IVLP involves the application of an in vivo isolated perfusion circuit to an implanted lung. This study aimed to explore the effectiveness of IVLP vs conventional post-lung transplant (LTx) extracorporeal membrane oxygenation (ECMO) treatment using an experimental swine LTx PGD model. METHODS: After 1.5-hour warm ischemia of the donor lungs, a left LTx was performed. Following the confirmation of PGD development, pigs were divided into 3 groups (n = 5 each): control (no intervention), ECMO, and IVLP. After 2 hours of treatment, a 4-hour functional assessment was conducted, and samples were obtained. RESULTS: Significantly better oxygenation was achieved in the IVLP group (p ≤ 0.001). Recovery was confirmed immediately and maintained during the following 4-hour observation. The IVLP group also demonstrated better lung compliance than the control group (p = 0.045). A histologic evaluation showed that the lung injury score and terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed significantly fewer injuries and a better result in the wet-to-dry weight ratio in the IVLP group. CONCLUSIONS: A 2-hour IVLP is technically feasible and allows for prompt recovery from PGD after LTx. The posttransplant short-duration IVLP strategy can complement or overcome the limitations of the current practice for donor assessment and PGD management.

Phase II Study of Intraperitoneal Administration of Paclitaxel Combined with S-1 and Cisplatin for Gastric Cancer with Peritoneal Metastasis.

BACKGROUND: Intraperitoneal chemotherapy is promising for gastric cancer with peritoneal metastasis. Although a phase III study failed to show a statistically significant superiority of intraperitoneal paclitaxel combined with S-1 and intravenous paclitaxel, the sensitivity analysis suggested clinical efficacy. Thus, attempts to combine intraperitoneal paclitaxel with other systemic therapies with higher efficacy have been warranted. We sought to explore the efficacy of intraperitoneal paclitaxel with S-1 and cisplatin. PATIENTS AND METHODS: Gastric cancer patients with peritoneal metastasis were enrolled in the phase II trial. In addition to the established S-1 and cisplatin regimen every 5 weeks, intraperitoneal paclitaxel was administered on days 1, 8, and 22 at a dose of 20 mg/m2. The primary endpoint was overall survival rate at 1 year after treatment initiation. Secondary endpoints were progression-free survival and toxicity. RESULTS: Fifty-three patients were enrolled and fully evaluated for efficacy and toxicity. The 1-year overall survival rate was 73.6% (95% confidence interval 59.5-83.4%), and the primary endpoint was met. The median survival time was 19.4 months (95% confidence interval, 16.1-24.6 months). The 1-year progression-free survival rate was 49.6% (95% confidence interval, 34.6-62.9%). The incidences of grade 3/4 hematological and non-hematological toxicities were 43% and 47%, respectively. The frequent grade 3/4 toxicities included neutropenia (25%), anemia (30%), diarrhea (13%), and anorexia (17%). Intraperitoneal catheter and implanted port-related complications were observed in four patients. There was one treatment-related death. CONCLUSIONS: Intraperitoneal paclitaxel combined with S-1 and cisplatin is well tolerated and active in gastric cancer patients with peritoneal metastasis.

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.