CXC chemokines and chemokine receptors in gastric cancer: from basic findings towards therapeutic targeting

Gastric cancer is the fourth most common cancer, and the second-highest cause of cancer-related deaths worldwide. Despite extensive research to identify novel diagnostic and therapeutic agents, patients with advanced gastric cancer suffer from a poor quality of life and poor prognosis, and treatment is dependent mainly on conventional cytotoxic chemotherapy. To improve the quality of life and survival of gastric cancer patients, a better understanding of the underlying molecular pathologies, and their application towards the development of novel targeted therapies, is urgently needed. Chemokines are a group of small proteins associated with cytoskeletal rearrangements, the directional migration of several cell types during development and physiology, and the host immune response via interactions with G-protein coupled receptors. There is also growing evidence to suggest that chemokines not only play a role in the immune system, but are also involved in the development and progression of tumors. In gastric cancer, CXC chemokines and chemokine receptors regulate the trafficking of cells in and out of the tumor microenvironment. CXC chemokines and their receptors can also directly influence tumorigenesis by modulating tumor transformation, survival, growth, invasion and metastasis, as well as indirectly by regulating angiogenesis, and tumor-leukocyte interactions. In this review, we will focus on the roles of CXC chemokines and their receptors in the development, progression, and metastasis of gastric tumors, and discuss their therapeutic potential for gastric cancer.

Robotic versus laparoscopic gastrectomy for gastric cancer: comparison of short-term surgical outcomes

BACKGROUND

Robot-assisted gastrectomy (RAG) is a new minimally invasive surgical technique for gastric cancer. This study was designed to compare RAG with laparoscopy-assisted gastrectomy (LAG) in short-term surgical outcomes.

METHODS

Between October 2011 and August 2014, 423 patients underwent robotic or laparoscopic gastrectomy for gastric cancer: 93 RAG and 330 LAG. We performed a comparative analysis between RAG group and LAG group for clinicopathological characteristics and short-term surgical outcomes.

RESULTS

RAG was associated with a longer operative time (P < 0.001), lower blood loss (P = 0.001), and more harvested lymph nodes (P = 0.047). Only three patients in LAG group had positive margins, and R0 resection rate for RAG and LAG was similar (P = 0.823). The RAG group had postoperative complications of 9.8 %, comparable with those of the LAG group (P = 0.927). Proximal margin, distal margin, hospital stay, days of first flatus, and days of eating liquid diet for RAG and LAG were similar. In the subgroup of serosa-negative patients, RAG had a longer operation time (P = 0.003), less intraoperative blood loss (P = 0.005), and more harvested lymph nodes (P = 0.04). However, in the subgroup of serosa-positive patients, RAG had a longer operation time (P = 0.001), but no less intraoperative blood loss (P = 0.139) and no more harvested lymph nodes (P = 0.139). Similarly, in the subgroup of total gastrectomy patients, RAG had a longer operation time (P = 0.018), but no less intraoperative blood loss (P = 0.173).

CONCLUSIONS

The comparative study demonstrates that RAG is as acceptable as LAG in terms of surgical and oncologic outcomes. With lower estimated blood loss, acceptable complications, and radical resection, RAG is a promising approach for the treatment of gastric cancer. However, the indication of patients for RAG is critical.

Prediction of risk factors for lymph node metastasis in early gastric cancer

AIM: To explore risk factors for lymph node metastases in early gastric cancer (EGC) and to confirm the appropriate range of lymph node dissection.

METHODS: A total of 202 patients with EGC who underwent curative gastrectomy with lymphadenectomy in the Department of Surgery, Xinhua Hospital and Ruijin Hospital of Shanghai Jiaotong University Medical School between November 2003 and July 2009, were retrospectively reviewed. Both the surgical procedure and the extent of lymph node dissection were based on the recommendations of the Japanese gastric cancer treatment guidelines. The macroscopic type was classified as elevated (type I or IIa), flat (IIb), or depressed (IIc or III). Histopathologically, papillary and tubular adenocarcinomas were grouped together as differentiated adenocarcinomas, and poorly differentiated and signet-ring cell adenocarcinomas were regarded as undifferentiated adenocarcinomas. Univariate and multivariate analyses of lymph node metastases and patient and tumor characteristics were undertaken.

RESULTS: The lymph node metastases rate in patients with EGC was 14.4%. Among these, the rate for mucosal cancer was 5.4%, and 8.9% for submucosal cancer. Univariate analysis showed an obvious correlation between lymph node metastases and tumor location, depth of invasion, morphological classification and venous invasion (χ² = 122.901, P = 0.001; χ² = 7.14, P = 0.008; χ² = 79.523, P = 0.001; χ² = 8.687, P = 0.003, respectively). In patients with submucosal cancers, the lymph node metastases rate in patients with venous invasion (60%, 3/5) was higher than in those without invasion (20%, 15/75) (χ² = 4.301, P = 0.038). Multivariate logistic regression analysis revealed that the depth of invasion was the only independent risk factor for lymph node metastases in EGC [P = 0.018, Exp (B) = 2.744]. Among the patients with lymph node metastases, 29 cases (14.4%) were at N1, seven cases were at N2 (3.5%), and two cases were at N3 (1.0%). Univariate analysis of variance revealed a close relationship between the depth of invasion and lymph node metastases at pN₁ (P = 0.008).

CONCLUSION: The depth of invasion was the only independent risk factor for lymph node metastases. Risk factors for metastases should be considered when choosing surgery for EGC.

Dichloroacetate attenuates hypoxia-induced resistance to 5-fluorouracil in gastric cancer through the regulation of glucose metabolism

In this study, we investigated whether gastric cancer with hypoxia-induced resistance to 5-fluorouracil (5-FU) could be re-sensitized following treatment with low-dose dichloroacetate (DCA), an inhibitor of the glycolytic pathway. The expression profiles of hypoxia-inducible factor-1α (HIF-1α) and pyruvate dehydrogenase kinase-1 (PDK-1) were analyzed in tissues from 10 patients with gastric cancer who had different responses to adjuvant 5-FU treatment. For the in vitro assays, cell viability and apoptosis were evaluated with and without treatment with 20mM DCA in the AGS and MKN45 cell lines, as well as in PDK1 knockdown cell lines. The expression levels of HIF-1α and PDK-1 were both elevated in the tumor tissues relative to the normal gastric tissues of most patients who showed recurrence after adjuvant 5-FU treatment. Cellular viability tests showed that these cell lines had a lower sensitivity to 5-FU under hypoxic conditions compared to normoxic conditions. Moreover, the addition of 20mM DCA only increased the sensitivity of these cells to 5-FU under hypoxic conditions, and the resistance to 5-FU under hypoxia was also attenuated in PDK1 knockdown cell lines. In conclusion, DCA treatment was able to re-sensitize gastric cancer cells with hypoxia-induced resistance to 5-FU through the alteration of glucose metabolism.

Survivin: Potential role in diagnosis, prognosis and targeted therapy of gastric cancer

Survivin is a protein that is highly expressed in a vast number of malignancies, but is minimally expressed in normal tissues. It plays a role as an inhibitor of cell death in cancer cells, thus facilitating the growth of these cells. In the case of gastric cancer, survivin is over-expressed in tumor cells and plays a role in the carcinogenesis process. Several studies on gastric cancer have indicated that there is a relationship between survivin expression and the ultimate behavior of the carcinoma. Since the expression pattern of survivin is selective to cancer cells, it has been described as an “ideal target” for cancer therapy. Currently, several pre-clinical and clinical trials are on-going to investigate the effects of interfering with survivin function in cancer cells as a biologic therapy. Survivin is a potentially significant protein in the diagnosis, prognosis and treatment of gastric tumors.

Polyphyllin I inhibits gastric cancer cell proliferation by downregulating the expression of fibroblast activation protein alpha (FAP) and hepatocyte growth factor (HGF) in cancer-associated fibroblasts

The aim of this study was to identify the anti-cancer mechanism of Polyphyllin I (PPI) on gastric cancer cells via its activity on cancer-associated fibroblasts (CAFs). We cultured purified gastric CAFs obtained from fresh human gastric cancer tissue and examined the effect of Polyphyllin I on CAF proliferation using a colorimetric viability assay. In addition, we established a nude mouse xenograft model to examine the effect of Polyphyllin I administration on tumorigenesis. Using Western analysis, we quantified protein expression of the CAF-derived cytokines fibroblast activation protein alpha (FAP), secreted protein acidic and cysteine rich (SPARC), stromal cell-derived factor 1 (SDF-1), hepatocyte growth factor tenascin-C (TNC), and hepatocyte growth factor (HGF) in both in vitro and in vivo models. We found that Polyphyllin I inhibits the proliferation of CAFs in a concentration-dependent manner. Following treatment with 2 μg/ml PPI for 24 h in vitro, the expression of FAP, SDF-1 and HGF protein in CAFs was significantly lower than that in the control group, but there was no significant difference in SPARC and TNC protein expression between the two groups. In the nude mouse xenograft model, the tumor inhibition rate was 45.5% when PPI was administered early and 29.4% with administration in the third week. The expression of FAP and HGF in the xenografts was significantly decreased, while the expression of SPARC, SDF-1, and TNC was largely unaltered. Altogether, these data suggest that Polyphyllin I can inhibit the proliferation of gastric cancer cells by downregulating the expression of FAP and HGF in CAFs in vivo.

Evaluation of clinicopathological factors related to the prognosis of gastric neuroendocrine carcinoma

BACKGROUND

Research on the clinicopathology and prognosis of gastric neuroendocrine carcinoma (GNEC) is rare, and a uniform standard for treatment has not been established. Therefore, we retrospectively analyzed the clinical data of 132 cases of GNEC to investigate the factors influencing prognosis.

METHODS

A total of 132 patients diagnosed with GNEC at Fujian Medical University Union Hospital from January 2006 to December 2013 were enrolled. This study was performed to analyze the factors related to patient prognosis.

RESULTS

In total, 58 men and 74 women whose ages ranged from 38 to 83 years old (62 ± 10) were enrolled. The 1- and 3-year survival rates for these patients were 83.9% and 47.6%, respectively. Of these patients, 100 underwent radical resection, 22 underwent palliative resection, and 10 received chemotherapy alone. The median survival times following radical resection, palliative resection and chemotherapy alone were 48, 20 and 12 months, respectively (P < 0.01). Univariate and multivariate survival analyses of patients who underwent radical resection showed that tumor size, N stage, Ki-67 labeling index, mitotic index and the application of postoperative adjuvant chemotherapy were independent factors affecting patient prognosis. The correlation analysis of the Ki-67 labeling index and mitotic index with prognosis showed that patient survival decreased significantly when the Ki-67 labeling index increased (P < 0.05).

CONCLUSIONS

Patients who underwent radical resection had the best prognosis among GNEC. For these patients, tumor size, N stage, Ki-67 labeling index, mitotic index and the application of postoperative adjuvant chemotherapy were the clinicopathological factors significantly associated with patient prognosis.

Impact of tumor location on clinical outcomes of gastric endoscopic submucosal dissection

AIM

To determine whether there is a correlation between the location of the lesion and endoscopic submucosal dissection (ESD) outcome.

METHODS

From January 2008 to December 2010, ESD of 1443 gastric tumors was performed. En bloc resection rate, complete resection rate, procedure time and complication rate were analyzed according to the tumor location.

RESULTS

The rates of en bloc resection and complete resection were 91% (1318/1443) and 89% (1287/1443), respectively. The post-ESD bleeding rate was 4.3%, and perforation rate was 2.7%. Tumors located in the upper third of the stomach were associated with a longer procedure time and significantly higher rates of incomplete resection, piecemeal resection, and perforation than tumors below the upper third of the stomach. Posterior wall lesions had significantly longer procedure times and higher rates of incomplete resection and piecemeal resection than lesions in other locations. In multivariate analysis, posterior wall lesions and upper third lesions were significantly associated with incomplete resection and perforation, respectively. In post-ESD bleeding analysis, location was not a significant related factor.

CONCLUSION

More advanced endoscopic techniques are required during ESD for lesions located in the upper third or posterior wall of the stomach to decrease complications and improve therapeutic outcomes.

Short-term healing process of artificial ulcers after gastric endoscopic submucosal dissection

BACKGROUND/AIMS

The relationship between the appearance of an ulcer and postoperative bleeding after gastric endoscopic submucosal dissection (ESD) is not well understood. To explore this potential relationship, we retrospectively analyzed the short-term healing process of ESD.

METHODS

A total of 520 consecutive lesions in 434 patients seen between January 2004 and December 2009 were retrospectively investigated. At the second-look endoscopy, which occurred between 1 and 8 days after ESD, artificial ulcers were categorized into 6 patterns according to Forrest's classification: spurting bleeding, oozing bleeding, non-bleeding visible vessel, adherent clot, black base/spot, and clean base. From these data, a short-term healing model of the artificial ulcer was generated.

RESULTS

Ulcer base changed gradually from a bloody to a clean one. The bleeding or non-bleeding visible vessel categories, which occurred in approximately one quarter of the ulcers within 3 days of ESD, were rarely observed 4 days after ESD.

CONCLUSIONS

Ulcers that occur after gastric ESD heal in line with a specific time course, and it appears that most healing occurs without massive bleeding.

Efficacy and safety of 0.4 percent sodium hyaluronate for endoscopic submucosal dissection of gastric neoplasms

AIM: To evaluate the efficacy and safety of sodium hyaluronate solution (SH) in endoscopic submucosal dissection (ESD) of gastric neoplasms.

METHODS: A prospective multicenter randomized, double blind, controlled trial was designed and utilized in this study. A total of 76 patients with 5-20 mm sized gastric neoplasms were enrolled at three academic hospitals in South Korea from June 2011 to October 2011. Patients were randomly assigned to the 0.4% sodium hyaluronate or control groups. All lesions underwent endoscopic ESD. ESD was performed with 0.4%SH and normal saline (NS) solution for submucosal injection. Efficacy was assessed using en bloc resection and the number of additional injections. Secondary evaluation variables were the volume of injection material, steepness of mucosal elevation, bleeding rate, procedural time and operator satisfaction. Finally, the safety was assessed by analyzing adverse events during the study.

RESULTS: The usefulness rate in the 0.4%SH group and the controlled group had statistically significant difference under intention to treat (ITT) analysis (90.91% vs 61.11% P = 0.0041). Under per protocol (PP), the usefulness rate is statistically significant different (93.10% vs 61.76%, P = 0.0036). The difference in volume of the solution injected between 0.4%SH group and the controlled group and NS group was also statistically significant under intention to treat and per protocol analysis (ITT: 0.03 ± 0.02 mL vs 0.06 ± 0.03 mL, P = 0.0003, PP: 0.03 ± 0.02 mL vs 0.06 ± 0.03 mL, P = 0.0004). Satisfaction above the grade good was significantly higher in the SH group under intention to treat and per protocol analysis (ITT: 90.91% vs 61.11%, P = 0.0041, PP = 93.11% vs 61.77%, P = 0.0022). Adverse events above grade 3 were not noticed in either group. All adverse events were treated and were judged as not associated with the submucosal injection solutions.

CONCLUSION: 0.4%SH solution is a safe and effective agent that doesn’t cause any significant adverse events and is useful for submucosal injection during ESD.

Correlative studies on bFGF mRNA and MMP-9 mRNA expressions with microvascular density, progression, and prognosis of gastric carcinomas

AIM: To investigate the mRNA expressions of bFGF and MMP-9 in gastric carcinomas so as to reveal their correlations with tumor microvascular density (MVD), invasion, metastasis, and prognosis.

METHODS: In situ hybridization and immunohistochemical techniques were used to detect the expressions of bFGFmRNA and MMP-9mRNA and the proteins of CD34 in 105 specimens of gastric carcinomas.

RESULTS: In situ hybridization study showed that positive rates of bFGF mRNA and MMP-9mRNA expressions were 60.95% and 59.19%; the mean MVD was 46.09±11.52 and 43.75±13.41, respectively in piece/0.72 mm² in tumors with bFGFmRNA and MMP-9mRNA positive expressions, which were significantly higher than those with negative expression (29.41±12.47; 33.45±13.92 piece/0.72 mm², respectively). The positive expression rates of bFGFmRNA and MMP-9mRNA were correlated to the tumor invasion depth (r_s = 0.211, P = 0.031; r_s = 0.335, P = 0.001), growing pattern (r_s = 0.324, P = 0.001; r_s = 0.267, P = 0.006), vessel invasion (r_s = 0.579, P = 0.001; r_s = 0.209, P = 0.032), lymph node metastasis (r_s = 0.405, P = 0.001; r_s = 0.343, P = 0.001) and distant metastasis (r_s = 0.474, P = 0.001; r_s = 0.468, P = 0.001), but not correlated to tumor type (r_s = 0.134, P = 0.173; r_s = 0.103, P = 0.145) and differentiations (r_s = 0.096, P = 0.332; r_s = 0.102, P = 0.298). The mean MVD was much higher in the tumors with infiltrating growth at stage T₃-T₄, with vessel invasion, lymph node metastasis and distant metastasis than those with expanding growth type (t = 10.105, P = 0.001) at stage T₁-T₂ (t = 5.961, P = 0.001), with non-vessel invasion (t = 7.394, P = 0.001), non-lymph node metastasis (t = 3.819, P = 0.01) and non-distant metastasis (t = 10.578, P = 0.001). Positive correlation was observed between MVD and the expressions of bFGFmRNA and MMP-9mRNA (t = 3.207, P = 0.002; t = 7.035, P = 0.001, respectively). The mean survival time and 5-year survival rate were lower in cases with MVD over 39.5 and the positive expressions of bFGFmRNA and MMP-9mRNA than those with MVD less than 39.5 and the negative expressions of bFGFmRNA and MMP-9mRNA.

CONCLUSION: bFGF and MMP-9 promote the angiogenesis of the gastric cancers. Detection of the expressions of bFGF and MMP-9 can serve as a useful index to determine the angiogenesis, invasion, metastasis, and prognosis of gastric cancers.

[Epidemiological characteristics of gastric cancer in China, 2015]

Objective: To estimate the morbidity and mortality of gastric cancer and its distribution in China in 2015 and provide information for future cancer prevention and control study and policy decision. Methods: In 2018, a total of 501 cancer registry systems reported data to the office of National Central Cancer Registry, and the data from 368 cancer registry systems met the criteria. The overall, gender specific, age specific and area specific morbidity and mortality rates of gastric cancer in China were estimated based on national population data in 2015. Chinese standard population in 2000 and World Segi's population data were used to calculate the age-standardized rates (ASR) of morbidity and mortality, including ASR of China and the world. Results: In 2015, the qualified 368 cancer registry system covered a total of 309 553 499 population in China, including 156 934 140 males and 152 619 359 females. We estimated that there were 403 000 new gastric cancer cases, with the crude morbidity rate of 29.31 per 100 000, ASR China of 18.68 per 100 000, ASR world of 18.57 per 100 000, and a cumulative rate of 2.29% for 0-74 years. There were 290 900 new gastric cancer deaths, with the crude mortality rate of 21.16 per 100 000, ASR China of 13.08 per 100 000, ASR world of 12.92 per 100 000, and a cumulative rate of 1.5% for 0-74 years. Gastric cancer ranked second as the most common cancers and third as the most common cancer causes of death in China. In general, both the morbidity rate (ASR China, male: 26.54 per 100 000; female: 11.09 per 100 000; rural area: 21.82 per 100 000; urban area: 16.37 per 100 000) and mortality rate (ASR China, male: 18.75 per 100 000; female: 7.72 per 100 000; rural area: 15.84 per 100 000; urban area: 11.05 per 100 000) were higher in males than those in females, and higher in rural area than those in urban area. The morbidity and mortality rates of gastric cancer increased from the age of 40 years and peaked in age group of 80-years. The case number of gastric cancer significantly increased from the age group of 50-years, peaked at 60-70 years, and the majority of cases occured in age group of 55-80 years. There was an overall consistent trend of the age-specific morbidity and mortality rates across different subgroups by sex and geographic areas, with the rates were higher in males than those in females, and higher in rural area than that in urban area. Conclusions: The incidence of gastric cancer varied with sex, age and areas (urban area and rural area). The present analysis provides the latest data on the prevalence of gastric cancer in China, which can help optimize the current screening guidelines and the prevention and control strategies of gastric cancer to reduce the disease burden caused by gastric cancer in China.

Induction of apoptosis of human gastric carcinoma SGC-7901 cell line by 5, 7-dihydroxy-8-nitrochrysin in vitro

AIM: To investigate the effect of 5, 7-dihydroxy-8-nitrochrysin (NOChR) on apoptosis of human gastric carcinoma SGC-7901 cell line.

METHODS: SGC-7901 cells were cultured in vitro and the inhibitory effect of NOChR on proliferation of SGC-7901 cells was measured by using an MTT assay. NOChR-induced apoptosis rate of SGC-7901 cells was detected using flow cytometry (FCM) with PI staining. DNA ladder bands were observed by DNA agarose gel electrophoresis. The influence of NOChR on the proxisome proliferator-activated receptor-γ (PPARγ), Bcl-2 and Bax protein expression of SGC-7901 cells was analyzed by Western blot.

RESULTS: MTT assay showed that NOChR markedly inhibited proliferation of SGC-7901 cells in a dose-dependent manner, and when IC₅₀ was 4.14 μmol/L, the potency of NOChR was 10 times than that of lead compound, chrysin (ChR, IC₅₀ was 40.56 μmol/L), and was similar to 5-fluorouracil (5-FU, IC₅₀ was 4.51 μmol/L). FCM with propidium iodide (PI) staining demonstrated that the apoptosis rates of SGC-7901 cells treated with 1.25, 5.00 and 20.00 μmol/L NOChR for 48 h were 9.8% ± 0.2%, 36.8% ± 1.9% and 45.5% ± 3.5%, respectively, and were significantly higher when treated with 5.00 and 20.00 μmol/L NOChR than that with 20.00 μmol/L ChR (12.9% ± 1.5%). DNA agarose gel electrophoresis showed that treatment of SGC-7901 cells with 20.00 μmol/L NOChR for 48 h resulted in typical DNA ladder bands of DNA of SGC-7901 cells, which could be eliminated by treating with 10.00 μmol/L GW9662, a blocker of PPARγ. Western blot analysis revealed that after 24 h of treatment with 20.00 μmol/L NOChR, PPARgamma and Bax protein expression of SGC-7901 cells increased but Bcl-2 expression decreased; however, pre-incubation with 10.00 μmol/L GW9662 could efficiently antagonize and weaken the regulatory effect of 20.00 μmol/L NOChR on Bax and Bcl-2 protein expression of SGC-7901 cells.

CONCLUSION: NOChR induces apoptosis of SGC-7901 cell lines by activating PPARγ and decreasing ratio of Bcl-2 to Bax.

Endoscopic Submucosal Dissection versus Surgery for Undifferentiated-Type Early Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND/AIMS

The use of endoscopic submucosal dissection (ESD) for treating undifferentiated-type early gastric cancer is controversial. The objective of this study was to perform a meta-analysis to compare the long-term outcomes of ESD and surgery for undifferentiated-type early gastric cancer.

METHODS

The PubMed, Cochrane Library, and EMBASE databases were used to search for relevant studies comparing ESD and surgery for undifferentiated-type early gastric cancer. The methodological quality of the included publications was evaluated using the Risk of Bias Assessment tool for Nonrandomized Studies. The rates of overall survival, recurrence, adverse event, and complete resection were determined. Odds ratios (ORs) and 95% confidence intervals (CIs) were also evaluated.

RESULTS

This meta-analysis enrolled five studies with 429 and 1,236 participants undergoing ESD and surgery, respectively. No significant difference was found in the overall survival rate between the ESD and surgery groups (OR, 2.29; 95% CI, 0.98-5.36; p=0.06). However, ESD was associated with a higher recurrence rate and a lower complete resection rate. The adverse event rate was similar between the two groups.

CONCLUSION

ESD with meticulous surveillance esophagogastroduodenoscopy may be as effective and safe as surgery in patients with undifferentiated-type early gastric cancer. Further large-scale, randomized, controlled studies from additional regions are required to confirm these findings.

Helicobacter pylori serological biomarkers of gastric cancer risk in the MCC-Spain case-control Study

BACKGROUND

Helicobacter pylori infection is one of the main risk factors for non-cardia gastric cancer. However, only a minority of infected persons develop the disease. This study aims at identifying H. pylori related serological biomarkers of risk for gastric cancer.

METHODS

Incident gastric cancer cases and population controls (age, sex and region frequency-matched) from the MCC-Spain multicase-control Study were included. Seroreactivities against 16H. pylori proteins were determined using multiplex serology. Infection was defined as seropositivity against≥4 proteins. Relation of serological results to non-cardia and cardia gastric cancer was assessed using multivariable mixed logistic regression and principal components analysis.

RESULTS

Seroprevalence was 88% among 2071 controls, 95% among 202 non-cardia gastric cancer cases (OR=1.9 (95% CI: 1.0-3.6)) and 85% among 62 cardia cancer cases (OR=0.5 (95% CI: 0.3-1.1)). In infected subjects, seropositivity for UreA, HP231, NapA and Cagδ was associated with lower non-cardia gastric cancer risk, while seropositivity for CagA and VacA was associated with higher risk. Seropositivity for CagA and seronegativity for Cagδ maintained the association after additional adjustment by serostatus of significant proteins. We identified two antibody reactivity patterns: the "virulent-pattern", related to a threefold higher risk of non-cardia gastric cancer and the "non-virulent pattern", related to a 60% decreased risk (4th vs. first quartile).

CONCLUSIONS

In our population, people seropositive for H. pylori were characterized by two patterns of antibody reactivity against H. pylori proteins: 1) Combined high seroreactivity against several proteins, associated with a lower non-cardia gastric cancer risk, and 2) High seroreactivity against CagA and VacA, associated with an increased risk.

Simple Analysis of the Computed Tomography Features of Gastric Schwannoma

OBJECTIVE

The objective of this study was to assess the computed tomography (CT) findings of gastric schwannoma (GS) and identify the difference between large (> 5 cm) and small (≤ 5 cm) GS.

MATERIALS AND METHODS

CT findings of 38 pathologically proven cases of GSs were retrospectively reviewed. The CT evaluation of GS included categorical variables (location, contour, growth pattern, enhancement pattern, necrosis, ulceration, calcification, and lymph nodes) and continuous variables (size, CT value of 3 phases, and enhancement degree). The lesion was divided into 2 groups (large [> 5 cm] and small [≤ 5 cm] GS) according to the tumor size. The Fisher exact test was used for categorical variables and the Student t or Mann-Whitney U test for continuous variables.

RESULTS

Of the 38 patients, there were 32 women and 6 men. The median age was 54.5 years (range 39-79). Most of patients (65.8%, [25 of 38]) had nonspecific gastrointestinal symptoms such as abdominal or gastric pain, fullness and discomfort, bleeding, and melena. The tumors were mainly located in the stomach body (71.1% [27 of 38]), and the mean diameter was 3.7 cm (range 1.5 cm-10.3 cm), of which included large (> 5 cm) (n = 8) and small (≤ 5 cm) (n = 30). All of the GSs were benign, 9 of whom had palpable perigastric lymph nodes, which confirmed by pathology for the reactive inflammatory hyperplasia. Growth pattern, pattern of enhancement, necrosis, calcification, surface ulceration, and lymph node in the CT images were found to be significant variables for differentiating large (> 5 cm) and small (≤ 5 cm) GS (P < .05).

CONCLUSION

GSs were predominantly located at the gastric body and occurred most frequently in women between the ages of 40-70 years, and showed gradual enhancement after contrast enhancement. Palpable perigastric lymph nodes could not be considered as malignant factor of GS. There 7 computed CT criteria are significant difference between large (> 5 cm) and small (≤ 5 cm) GS.

Pharmacological Intervention through Dietary Nutraceuticals in Gastrointestinal Neoplasia

Neoplastic conditions associated with gastrointestinal (GI) tract are common worldwide with colorectal cancer alone accounting for the third leading rate of cancer incidence. Other GI malignancies such as esophageal carcinoma have shown an increasing trend in the last few years. The poor survival statistics of these fatal cancer diseases highlight the need for multiple alternative treatment options along with effective prophylactic strategies. Worldwide geographical variation in cancer incidence indicates a correlation between dietary habits and cancer risk. Epidemiological studies have suggested that populations with high intake of certain dietary agents in their regular meals have lower cancer rates. Thus, an impressive embodiment of evidence supports the concept that dietary factors are key modulators of cancer including those of GI origin. Preclinical studies on animal models of carcinogenesis have reflected the pharmacological significance of certain dietary agents called as nutraceuticals in the chemoprevention of GI neoplasia. These include stilbenes (from red grapes and red wine), isoflavones (from soy), carotenoids (from tomatoes), curcuminoids (from spice turmeric), catechins (from green tea), and various other small plant metabolites (from fruits, vegetables, and cereals). Pleiotropic action mechanisms have been reported for these diet-derived chemopreventive agents to retard, block, or reverse carcinogenesis. This review presents a prophylactic approach to primary prevention of GI cancers by highlighting the translational potential of plant-derived nutraceuticals from epidemiological, laboratory, and clinical studies, for the better management of these cancers through consumption of nutraceutical rich diets and their intervention in cancer therapeutics.

Occupational exposures and odds of gastric cancer: a StoP project consortium pooled analysis

BACKGROUND

Gastric cancer pathogenesis represents a complex interaction of host genetic determinants, microbial virulence factors and environmental exposures. Our primary aim was to determine the association between occupations/occupational exposures and odds of gastric cancer.

METHODS

We conducted a pooled-analysis of individual-level data harmonized from 11 studies in the Stomach cancer Pooling Project. Multivariable logistic regression was used to estimate the odds ratio (OR) of gastric cancer adjusted for relevant confounders.

RESULTS

A total of 5279 gastric cancer cases and 12 297 controls were analysed. There were higher odds of gastric cancer among labour-related occupations, including: agricultural and animal husbandry workers [odds ratio (OR) 1.33, 95% confidence interval (CI): 1.06-1.68]; miners, quarrymen, well-drillers and related workers (OR 1.70, 95% CI: 1.01-2.88); blacksmiths, toolmakers and machine-tool operators (OR 1.41, 95% CI: 1.05-1.89); bricklayers, carpenters and construction workers (OR 1.30, 95% CI: 1.06-1.60); and stationary engine and related equipment operators (OR 6.53, 95% CI: 1.41-30.19). The ORs for wood-dust exposure were 1.51 (95% CI: 1.01-2.26) for intestinal-type and 2.52 (95% CI: 1.46-4.33) for diffuse-type gastric cancer. Corresponding values for aromatic amine exposure were 1.83 (95% CI: 1.09-3.06) and 2.92 (95% CI: 1.36-6.26). Exposure to coal derivatives, pesticides/herbicides, chromium, radiation and magnetic fields were associated with higher odds of diffuse-type, but not intestinal-type gastric cancer.

CONCLUSIONS

Based on a large pooled analysis, we identified several occupations and related exposures that are associated with elevated odds of gastric cancer. These findings have potential implications for risk attenuation and could be used to direct investigations evaluating the impact of targeted gastric cancer prevention/early detection programmes based on occupation.

Survival analysis based on human epidermal growth factor 2 status in stage II-III gastric cancer

AIM

To investigate human epidermal growth factor 2 (HER2) overexpression and validate its prognostic effect in stage II-III gastric cancer.

METHODS

We reviewed the data of patients who were diagnosed with gastric cancer between March 2008 and October 2013 at the Yonsei University Medical Center. Among these patients, 384 patients who met the inclusion criteria were analyzed retrospectively.

RESULTS

Thirty-two (8.3%) of the 384 stage II-III gastric cancer patients exhibited HER2 overexpression. The median follow-up duration was 26.0 mo. HER2-negative patients had superior recurrence-free survival (RFS) compared to HER2-positive patients (HR = 0.52, 95%CI: 0.30-0.89; P = 0.015). The median overall survival (OS) was significantly prolonged in the HER2-negative group compared with the HER2-positive group (55.0 mo vs 38.0 mo, HR = 0.43, 95%CI: 0.21-0.88, P = 0.021). OS was also prolonged in HER2-negative patients who received adjuvant chemotherapy compared to HER2-positive patients (55.0 vs 38.0 mo, HR = 0.42, 95%CI: 0.18-1.00, P = 0.051). In patients who did not receive adjuvant chemotherapy, the median RFS was prolonged in the HER2-negative group compared to the HER2-positive group (not reached vs 12.0 mo, HR = 0.17, 95%CI: 0.06-0.49, P = 0.001). In a multivariate analysis, HER2 status (HR = 0.421, 95%CI: 0.206-0.861, P = 0.018) and Eastern Cooperative Oncology Group performance status (HR = 2.002, 95%CI: 1.530-2.618, P < 0.001) were independent predictors of OS.

CONCLUSION

Our findings showed that HER2-positive patients had inferior OS and RFS. Stage II-III HER2-positive patients might be potential candidates for targeted therapies involving trastuzumab.

Clutch Cutter knife efficacy in endoscopic submucosal dissection for early gastric neoplasms

AIM

To compare the outcomes of endoscopic submucosal dissection (ESD) for gastric neoplasms using Clutch Cutter (ESD-C) or other knives (ESD-O).

METHODS

This was a single-center retrospective study. Gastric neoplasms treated by ESD between April 2016 and October 2017 at Kitakyushu Municipal Medical Center were reviewed. Multivariate analyses and propensity score matching were used to reduce biases. Covariates included factors that might affect outcomes of ESD, including age, sex, underlying disease, anti-thrombotic drugs use, tumor location, tumor position, tumor size, tumor depth, tumor morphology, tumor histology, ulcer (scar), and operator skill. The treatment outcomes were compared among two groups. The primary outcome was ESD procedure time. Secondary outcomes were en bloc, complete, and curative resection rates, and adverse events rates including perforation and delayed bleeding.

RESULTS

A total of 155 patients were included in this study; 44 pairs were created by propensity score matching. Background characteristics were quite similar among two groups after matching. Procedure time was significantly shorter for ESD-C (median; 49 min) than for ESD-O (median; 88.5 min) (P < 0.01). However, there was no significant difference in treatment outcomes between ESD-C and ESD-O including en bloc resection rate (100% in both groups), complete resection rate (100% in both groups), curative resection rate (86.4% vs 88.6%, P = 0.730), delayed bleeding (2.3% vs 6.8%, P = 0.62) and perforation (0% in both groups).

CONCLUSION

ESD-C achieved shorter procedure time without an increase in complication risk. Therefore, ESD-C could become an effective ESD option for gastric neoplasms.

Predictive Factors for Pain After Endoscopic Resection of Gastric Tumors

BACKGROUND

Abdominal pain is a common complaint following endoscopic resection (ER).

AIMS

To investigate the predictive factors for abdominal pain after ER.

METHODS

Patients who were scheduled to undergo endoscopic mucosal resection or endoscopic submucosal dissection for the treatment of gastric adenoma or cancer were prospectively enrolled. Pain scores were checked every 6 h after ER and whenever patients complained of pain by using a 0-10 pain scale. If the pain score exceeded 5, 25 mg of intravenous (IV) pethidine was administered.

RESULTS

Among 156 patients who underwent ER, 66 (42.3 %) received IV pethidine due to moderate/severe abdominal pain. Both the number of patients complaining of abdominal pain and the pain scores decreased with time following the procedure, with only a few patients complaining of mild abdominal pain 2 days after ER. Multivariate analysis showed that female sex [odds ratio (OR) 2.88; confidence interval (CI) 1.31-6.33], tumor location in the lower third of the stomach (OR 5.46; CI 2.31-12.92), and procedures time more than 60 min (OR 2.96; CI 1.26-6.98) were significant predictive factors for developing pain after ER.

CONCLUSIONS

Female sex, tumor location in the lower third of the stomach, and longer procedure time were significantly associated with pain after ER. Close monitoring and active management of pain is recommended for patients who have these risk factors. With these efforts, the majority of patients could experience pain relief within 2 days after the procedure.

Sporadic Gastric Well-Differentiated Neuroendocrine Tumors Have a Higher Ki-67 Proliferative Index

Well-differentiated neuroendocrine tumor (WDNET) of the stomach can arise in three distinct clinical settings: (1) in association with autoimmune atrophic gastritis, (2) in association with multiple neuroendocrine neoplasia type I (MEN I) or Zollinger-Ellison syndrome (ZES), or (3) sporadic. The Ki-67 proliferative index (PI) in gastric WDNETs in these three distinct clinical settings has not been evaluated in detail. Forty-five gastric WNETs underwent polypectomy (n = 4), endoscopic mucosal resection (n = 12), and surgical resection (n = 29) between 1994 and 2015 were included. H&E slides from each case were reviewed, and Ki-67 immunostain was performed on one representative tumor block. Ki-67 PI was determined by quantitative Aperio image analysis software in areas of strongest nuclear labeling ("hot spots"), and correlated with underlying clinical and pathological features. Twenty-one patients were male and 24 female with a median age of 57 years (range, 30-80 years). Tumors were classified as type I (n = 17), type II (n = 6), and type III (n = 22) WDNETs. Types II and III showed more advanced TNM stage compared to type I (p = 0.02, overall). WHO grade based on Ki-67 PI was higher in type III WDNETs [grade 1 (G1), n = 3; grade 2 (G2), n = 15; and grade 3 (G3), n = 4] than in type I WDNETs [G1, n = 5; G2, n = 12] and in type II WDNETs [G1, n = 2; G2, n = 4] (p = 0.050, overall). Ki-67 PI was significantly higher in type III WDNETs (mean ± SD = 13.0 ± 13.3 %) than in non-sporadic (type I and II) WDNETs (mean ± SD = 5.3 ± 3.3 %; p = 0.015). There was no difference in Ki-67 PI between type I WDNETs (mean ± SD = 5.2 ± 3.5 %) and type II WDNETs (mean ± SD = 5.6 ± 3.1%; p = 0.817). Higher Ki-67 PI was associated with higher tumor T stage (p = 0.003) and also tended to be associated with lymph node metastasis (p = 0.071). In the Kaplan-Meier survival analysis, type I was associated with a significantly longer disease-free survival (DFS) time compared to type II (p = 0.018) or III (0.010). Also, the WHO G3 group had a significantly shorter DFS time than the WHO G1 (p = 0.020) or G2 (p = 0.007) group. Gastric WDNET is a heterogeneous disease entity encompassing three clinical subtypes-type I, type II, and type III-having their own distinct clinicopathologic characteristics and prognosis. Our results showed that sporadic (type III) WDNET had a significantly higher Ki-67 PI than non-sporadic cases (type I or II); increased PI was associated with higher tumor stage. We also described four type III cases of morphologically WD gastric NET with WHO grade 3 on the basis of Ki-67 PI.

Gastric lipoma: a rare cause of haematemesis

Gastric lipomas are rare benign tumours of the stomach, representing less than 3% of all benign gastric neoplasms. They are usually asymptomatic but larger lesions can present with abdominal pain, gastric outlet obstruction and haematemesis. Malignant transformation is extremely rare. Accurate preoperative diagnosis can be established with computed tomography. Being benign, extensive surgery is not necessary and simple excision of the lesion is adequate. Small asymptomatic lesions can be followed up. We present a case of 80-year-old woman with gastric submucosal lipoma who presented with haematemesis.

Vonoprazan versus lansoprazole in the treatment of artificial gastric ulcers after endoscopic submucossal dissection: a randomized, open-label trial

Background

Vonoprazan is more potent and longer acting than traditional proton pump inhibitor. Although vonoprazan is expected to be superior to proton pump inhibitor, its efficacy in the treatment of gastric ulcers following endoscopic submucosal dissection (ESD) is not fully understood. The aim of this study was to evaluate the effectiveness of vonoprazan in artificial ulcer healing following ESD.

Methods

Patients with gastric tumors were randomly assigned to the vonoprazan group (group V) or lansoprazole group (group L) after ESD. Patients received intravenous lansoprazole (30 mg) twice on the day of ESD. Thereafter, patients were treated with vonoprazan (20 mg/day) in group V or lansoprazole (30 mg/day) in group L. Esophagogastroduodenoscopy was performed 4 and 8 weeks after the ESD.

Results

A total of 168 patients were analyzed. The 4-week healing rate for artificial ulcer was not significantly higher in group V versus group L (17/85, 20.0% vs. 14/83, 16.9%, respectively). In addition, there were no significant differences between the 4-week shrinkage rates between the two groups. Postoperative bleeding occurred in none of the patients in group V and three in group L. One patient in group V presented delayed perforation 2 days after ESD.

Conclusions

Vonoprazan might not be superior to lansoprazole in the healing of artificial gastric ulcer after ESD.

Trial registration: University hospital Medical Information Network (registration number: UMIN000016642), Registered 27 February 2015, https://www.umin.ac.jp/ctr/index-j.htm.

Strategies of laparoscopic spleen-preserving splenic hilar lymph node dissection for advanced proximal gastric cancer

For advanced proximal gastric cancer (GC), splenic hilar (No. 10) lymph nodes (LN) are crucial links in lymphatic drainage. According to the 14(th) edition of the Japanese GC treatment guidelines, a D2 lymphadenectomy is the standard surgery for advanced GC, and No. 10 LN should be dissected for advanced proximal GC. In recent years, the preservation of organ function and the use of minimally invasive technology are being accepted by an increasing number of clinicians. Laparoscopic spleen-preserving splenic hilar LN dissection has become more accepted and is gradually being used in operations. However, because of the complexity of splenic hilar anatomy, mastering the strategies for laparoscopic spleen-preserving splenic hilar LN dissection is critical for successfully completing the operation.