Comparative Study on the Anticancer Drug Potential of a Lectin Purified from Aloe Vera and Aloe-Emodin

Background:

The effect of Aloctin, a lectin purified from Aloe vera leaves, and aloe emodin an anthraquinone glycoside purified from the leaves of the same plant, on several cancer cell lines was investigated.

Methods:

Aloctin was isolated from A. vera leaf skin by ammonium sulphate precipitation and CNBr-Sepharose 4B-ovalbumin affinity chromatography. Specific new ligands for Aloctin were detected as fetuin and avidin by hemagglutination inhibition tests. The cytotoxic effect of Aloctin and aloe emodin on various human cancer cell lines was tested using MTT assay. Imatinib was tested as standard positive control. The mechanism underlying was tested by the Annexin V-FITC/PI test, with flow cytometry.

Results:

The most sensitive cells to Aloctin and aloe emodin treatment, were identified as AGS human gastric adenocarcinoma cells. The effect was concentration dependent. It was shown that this effect does not occur by apoptosis or necrosis. In Aloctin-imatinib combinations studies, Aloctin significantly increased the cytotoxic effect of imatinib in a dose-dependent manner. It is expected that the results of this study will reveal important findings for the future use of A. vera lectin as well as aloe emodin in cancer research and contribution to lectin biochemistry.

Preventable lifestyle and eating habits associated with gastric adenocarcinoma: A case-control study

Background: Besides the well-established risk factors for gastric adenocarcinoma (GaC), many other etiological factors remain largely unexplored. This large comprehensive case-control study aimed to investigate the preventable lifestyle and eating habits associated with GaC.

Methods: Consecutive patients with primary microscopically-confirmed GaC diagnosed in 2016-2018 were matched by sex, age, height, and socioeconomic status at a 1:1 ratio with healthy controls. Association of GaC versus control with investigated factors was assessed using the multivariable-adjusted conditional logistic regression for paired samples.

Results: Together 302 GaC patients and 302 healthy controls were investigated. Participants receiving higher education and those eating majorly vegetables had less frequently GaC. The majorly frying cooking habit was associated with a higher incidence of GaC. People complaining about poor sleep quality had more often GaC. The more often one smoked, the more often he/she had GaC. A higher frequency for having pickled food was associated with more frequent GaC, while having more frequently vegetables/fruit, beans, or kelps was associated with less often GaC. A greater preference for sour or bitter taste was associated with less frequent GaC. The frequencies of thin liquid intake after meal, swallowing hot food without adequate cooling, doing other things while eating, eating overnight food, and eating midnight snack were all positively associated with GaC, while going to bed regularly was associated with less often GaC.

Conclusions: Education level, sleep quality, smoking, the frequencies of use of several foods and seasonings, the preference for specific tastes, and various eating and living habits were associated with GaC. The findings offer important hints for further prospective investigations and for easy effective GaC-preventative strategy-making.

Efficacy of Three-Drug Induction Chemotherapy Followed by Preoperative Chemoradiation in Patients with Localized Gastric Adenocarcinoma

BACKGROUND

Preoperative induction chemotherapy followed by chemoradiation yields better R0 resection rates, pathologic complete response (pCR) rates and improved survival for localized gastric adenocarcinoma (GAC). We report the effect of three-drug induction chemotherapy on a large cohort of localized GAC patients.

METHODS

We identified 97 patients with localized GAC who received three-drug induction chemotherapy followed by preoperative chemoradiation therapy. We assessed various endpoints (overall survival [OS], recurrence-free survival [RFS], R0 resection and pCR rate).

RESULTS

The median follow-up time was 3.5 years (range; 0.4-16.7). The induction chemotherapy regimen was a fluoropyrimidine and a platinum compound (cisplatin or oxaliplatin) with a taxane (docetaxel or paclitaxel) for 95% of patients. Seventy-three (75.3%) out of 97 patients underwent planned surgery. R0 resection and pCR rae were 93.2 and 20.6%, respectively. Pathologic partial response (<50% residual carcinoma) rate was 50.7%. The median OS was 6.4 years (95% Cl 3.3-12.4) for the entire cohort and 11.1 years (95% Cl 7.1-not estimable) for patients that underwent surgery. The estimated 2- and 5-year OS rates were 72.4% (95% CI 62.1-80.3) and 54.3% (95% CI 43.2-64.1) for the entire cohort and 83.2% (95% CI 72.3--90.1) and 66% (95% CI 52.3-75.8) for patients that underwent surgery. Pathologic lesser stage (stage I/II vs. stage III/IV) (p = 0.001) and R0 resection (p = 0.02) were independently associated with longer RFS in the multivariate analysis.

CONCLUSION

Our data shows that three-drug combination is feasible without providing substantial advantage compared with two-drug combination in this setting of preoperative induction chemotherapy followed by chemoradiation and surgery.

IGF2-AS affects the prognosis and metastasis of gastric adenocarcinoma via acting as a ceRNA of miR-503 to regulate SHOX2

Disorder of long non-coding RNAs (LncRNAs) is found in various types of cancers and demonstrated to be associated with tumor occurrence and development. Our study found that lncRNA insulin growth factor 2 antisense (IGF2-AS) is up-regulated in gastric adenocarcinoma (GAC) tissues and correlated with poor prognosis in patients with GAC. Cell counting kit-8 (CCK8), colony formation, wound healing and transwell assays revealed that knockdown of IGF2-AS in BGC823 and SGC7901 cells significantly suppressed cell proliferation, migration and invasion. While, overexpression of IGF2-AS in AGS and MGC803 cells exhibited the opposite effects. RNA-FISH and subcellular fractionation assay found that most IGF2-AS was distributed in the cytoplasm, suggesting that IGF2-AS functioned as a potential ceRNA. RNA binding protein immunoprecipitation (RIP) assays further confirmed this assumption. By informatics prediction and luciferase reporter assay, we found that IGF2-AS functioned as an efficient miR-503 sponge and the level of miR-503 showed an inverse correlation with IGF2-AS. Short stature homeobox 2 (SHOX2) is predicted and verified as a target of miR-503. Moreover, IGF2-AS expression exhibited a negative correlation with miR-503 and a positive correlation with IGF2-AS. Subsequent rescue assay revealed that down-regulation of miR-503 or restoration of SHOX2 canceled IGF2-AS depletion-induced depression in proliferation and motility of BGC823 and SGC7901 cells. Meanwhile, up-regulation of miR-503 or down-regulation of SHOX2 decreased IGF2-AS overexpression induced promotion in proliferation and motility of AGS and MGC803 cells. In vivo tumorigenicity assay showed that knockdown of IGF2-AS significantly reduced tumor volume. Taken together, our results demonstrated that IGF2-AS takes important regulatory parts in GAC development by functioning as a ceRNA to regulate SHOX2 via sponging miR-503.

MiR-96-5p inhibition induces cell apoptosis in gastric adenocarcinoma

BACKGROUND

Gastric adenocarcinoma (GAC) mortality rates have remained relatively changed over the past 30 years, and it continues to be one of the leading causes of cancer-related death.

AIM

To search for novel miRNAs related to GAC prognosis and further investigate the effect of miR-96-5p on MGC-803 cells.

METHODS

The miRNA expression profile data of GAC based on The Cancer Genome Atlas were obtained and used to screen differently expressed miRNAs (DEMs) and DEMs related to GAC prognosis. Then, the expression of DEMs related to GAC prognosis was identified in GAC tumor samples and adjacent normal samples by qRT-PCR. The target gene, ZDHHC5, of miR-96-5p was predicted using TargetScan, miRTarBase, and miRDB databases and confirmed by luciferase reporter assay. Furthermore, MGC-803 cells were transfected with inhibitor NC, miR-96-5p inhibitor, si-ZDHHC5, or miR-96-5p inhibitor + si-ZDHHC5, and then cell apoptosis was detected by flow cytometry. The expression of ZDHHC5, Bcl-2, and COX-2 was detected using western blotting.

RESULTS

A total of 299 DEMs and 35 DEMs related to GAC prognosis were screened based on The Cancer Genome Atlas. Then compared with adjacent normal samples, the levels of miR-96-5p, miR-222-5p, and miR-652-5p were remarkably increased, while miR-125-5p, miR-145-3p, and miR-379-3p levels were reduced in GAC tumor samples (P < 0.01), which were consistent with bioinformatics analysis. Furthermore, ZDHHC5 was defined as a direct target gene of miR-96-5p. miR-96-5p inhibition increased the number of apoptotic cells as well as promoted the expression of ZDHHC5, Bcl-2, and COX-2 in MGC-803 cells (P < 0.01). After ZDHHC5 inhibition, the number of apoptotic cells and the expression of ZDHHC5, Bcl-2, and COX-2 were reduced. The addition of an miR-96-5p inhibitor partly reversed these effects (P < 0.01).

CONCLUSION

Our findings identified six miRNAs related to GAC prognosis and suggested that downregulated miR-96-5p might induce cell apoptosis via upregulating ZDHHC5 expression in MGC-803 cells.

Gastric lesions in free-living sea turtles: An underestimated disease that reflects the health of the ecosystem

Free-living marine turtles are constantly exposed to aggression factors and the gastrointestinal tract is one of the main gateways of entry. The objective of this study was to identify, and describe the anatomopathological alterations in the stomach of free-living marine turtles found dead on the beaches of the Microrregião dos Lagos, Rio de Janeiro, Brazil. Twenty-two sea turtles were necropsied, and stomach fragments were collected, fixed, and processed routinely. The presence of gastritis, parasitism, and adaptative morphological alteration of the cells were evaluated in a microscopic analysis. Descriptive statistics and Fisher's exact test were performed. Of the samples, 59.1% had stomach hyperemia. Microscopically, gastritis was found in 86.4% of cases, parasitism in 72.7%, and adaptive morphological alteration in 59.1%. There was an association between the presence of cellular adaptive morphological alteration and chronic inflammation. This the first report to describe the adaptive morphological changes observed in the stomach cells. The chronicity of the lesions was due to continuous aggressions to the tissue, with parasitism, garbage ingestion, and environmental pollutants as possible causes. The results obtained in this study demonstrate that the chronicity of the stomach lesions is due to continuous aggressions to this tissue, and the irritating factors have environmental origin, such as parasites, garbage, and toxic pollutants, including heavy metals, which are ingested by free-living sea turtles. This article demonstrates that stomach injuries in free-living marine turtles are frequent, severe, and possibly underdiagnosed; these lesions reflect the diseased ecosystem in which those animals live.

Apoptotic effect of fluoxetine through the endoplasmic reticulum stress pathway in the human gastric cancer cell line AGS

Gastric cancer is the fourth most common cancer in the world. Fluoxetine (FLX), a selective serotonin reuptake inhibitor, can inhibit the growth of cancer cells by inducing apoptotic cell death through various signaling pathways. This study was aimed to determine the mechanism of apoptotic cell death induced by FLX in AGS cells. MTT assay for cell viability test and colony forming assay was performed for detection of cell proliferation. Western blot analysis was conducted for protein expression. Increased fluorescence intensity and chromatin condensation were observed using DAPI staining. Production of reactive oxygen species (ROS) was measured by DCFDA assay. AGS cell proliferation was remarkedly inhibited by FLX in a dose-dependent manner starting at a concentration of 20 μM. The expression of death receptors was increased, which resulted in elevated expression of activated caspases and cleaved PARP, leading to FLX-induced apoptosis. Moreover, FLX significantly increased production of ROS, and N-acetyl cysteine, which scavenges ROS, attenuated the cytotoxic effects of FLX. In addition, treatment with FLX increased the expression of the endoplasmic reticulum (ER) stress marker, CHOP. P53 protein expression in AGS cells also decreased significantly with FLX treatment. Inhibition of ER stress significantly decreased the expressions of death receptor 5 (DR5), cleaved caspase 3, and cleaved PARP, but not to control levels. FLX-induced apoptosis in AGS involved upregulation of death receptors, ROS generation, and activation of ER stress.

Involvement of SLC39A6 in gastric adenocarcinoma and correlation of the SLC39A6 polymorphism rs1050631 with clinical outcomes after resection

BACKGROUND

The single-nucleotide polymorphism SLC39A6 rs1050631 is strongly implicated in esophageal squamous cell carcinoma, leading us to question whether it may also play a role in gastric adenocarcima (GA).

METHODS

We genotyped the SLC39A6 rs1050631 in 512 patients who underwent GA resection. All study subjects lived in an area of China with high GA incidence. Genotypes were examined for possible correlation with survival and recurrence. The potential involvement of SLC39A6 in gastric cancer was explored in clinical samples and cell culture studies.

RESULTS

Multivariable analysis showed that patients with the CT + TT genotype at SLC39A6 rs1050631 were at greater risk of recurrence (hazard ratio, HR 1.387, p = 0.004) and death (HR 1.429, p = 0.002) than patients with CC genotype. Median recurrence-free and overall survival were significantly shorter in patients with the CT + TT genotype (20, 27 months) than in patients with the CC genotype (36, 43 months, p = 0.001, p < 0.001). Patients with the CT + TT genotype who were male or ≥ 60 years, or who had a tumor ≥5 cm or a moderately differentiated tumor were at significantly higher risk of recurrence and death. SLC39A6 was overexpressed in tissues from GA patients and in GA cell lines, and SLC39A6 knockdown in GA cell lines inhibited their proliferation, migration and invasion.

CONCLUSION

SLC39A6 rs1050631 correlates with post-resection prognosis of GA patients and SLC39A6 may participate in GA onset or progression.

Prognostic factors associated with survival in a large cohort of gastric cancer patients resected over a decade at a single Italian center: the Cremona experience

BACKGROUND

Incidence of gastric cancer (GC) shows different distribution in Italy, with higher incidence in the north and center. We retrospectively analyzed the clinical data of patients resected at the Hospital of Cremona between January 2007 and December 2016. Available clinical variables were linked with survival to identify possible prognostic factors.

MATERIALS AND METHODS

Variables analyzed were age, sex, type of surgery, site, histology, invasion, nodal status, resection margins, grade, HER2 status, Helicobacter pylori infection (neo)adjuvant chemotherapy, adjuvant chemoradiotherapy, neutrophil-to-lymphocyte ratio, number of nodes removed and type of lymphadenectomy. Overall survival (OS) was estimated by the Kaplan-Meier method and differences between groups by the log-rank test. Data on OS were analyzed by Cox regression and the final model was obtained using the step-wise method.

RESULTS

379 patients were considered, out of which 195 were operated from 2007 to 2011 and 184 from 2012 to 2016. Median follow-up was 25.5 months, median OS 31.3 months and time to recurrence 23.2 months. D2 resection rate increased from 36% (period 2007-2011) to 74% in 2012-2016 (p = 0.01) with a higher mean number of nodes collected (20.98 for 2007-2011 and 23.53 for 2012-2016, p = 0.040). Only 37% of patients received a postoperative treatment. At multivariate analysis, variables associated with OS were age (p = 0.002), stage (p < 0.001), resection margins status (p < 0.001), adjuvant chemotherapy (p < 0.010) and tumor location (cardia vs non-cardia) (p = 0.029).

CONCLUSIONS

Our analysis shows that completeness of resection and lower stage are strong predictors of long-term survival in GC, providing the rationale for adjuvant and neoadjuvant approaches (chemotherapy, radiotherapy or combined). Cardial GC has worse prognosis compared to distal cancers.

TRIAL REGISTRATION NUMBER

Service evaluation number 256, protocol 16821/17, date 05 June 2017.

The expression of C-MYC in gastric adenocarcinoma is associated with PD-L1 and FOXP3 expression: C-MYC overexpression is a good prognostic factor

BACKGROUND

C-MYC appears to initiate and maintain tumorigenesis through modulation of immune regulatory molecules such as PD-L1. The aim of our research was to evaluate the clinical implication of C-MYC expression in gastric adenocarcinoma in relation to the expression of the immune regulatory molecules PD-L1 and FOXP3.

METHODS

Tissue samples were acquired from 182 cases of gastric adenocarcinoma that were surgically resected at Kyung Hee University Hospital at Gangdong from 2006 to 2012. Immunohistochemical staining for C-MYC, PD-L1, CD8 and FOXP3 was done.

RESULTS

C-MYC overexpression showed a significant correlation with smaller tumor size, lower T category, lower N category, lower recurrence rate, and less lymphatic invasion. And C-MYC overexpression was negatively correlated with PD-L1 expression. The tumoral FOXP3 was positively correlated with C-MYC overexpression and Tregs count. PD-L1 expression was positively correlated with Tregs, CD8 + T cells, and tumor infiltrating lymphocytes (TIL). Tregs count was positively correlated with CD8 + T cells and TIL. CD8 + T cells was positively correlated with TIL.

CONCLUSION

We discovered that the immune regulatory effect of C-MYC and PD-L1, and the tumor suppressor function of tumoral FOXP3 had a significant influence on the tumor microenvironment (Tregs, CD8 + T cells, and tumor infiltrating lymphocytes) in a complex manner. The C-MYC overexpression is a good prognostic factor in gastric adenocarcinoma.

ANTXR1 (TEM8) overexpression in gastric adenocarcinoma makes the protein a potential target of immunotherapy

BACKGROUND

Despite the promise of immunotherapy for gastric adenocarcinoma, choices for the selection of effective antigenic targets are very limited. Previously published data and our own in-house computational analysis have suggested that ANTXR1 is a potential target, simultaneously expressed in malignant tumor cells and the endothelial cells of the tumors. However, the expression pattern of ANTXR1 protein in clinical samples of gastric adenocarcinoma has not been fully evaluated.

METHODS

Using immunohistochemistry (IHC), we recorded the percentage of ANTXR1 positive cells separately in tumor cells and endothelial cells in the primary tumor, non-tumor gastric tissue adjacent to the primary tumor, and tumor in metastatic sites of 140 gastric adenocarcinoma patients. We also evaluated the association of ANTXR1 expression with the Lauren histological classification of the primary tumors, the patient's history of neoadjuvant chemotherapy and/or radiotherapy, and the patient's overall survival.

RESULTS

ANTXR1 was expressed in a mean of 73.89 ± 30.12% of tumor cells and 13.55 ± 20.53% of endothelial cells in the primary tumors. Intestinal adenocarcinomas had lower ANTXR1 expression in the tumor cells and higher ANTXR1 expression in the endothelial cells of the tumor regions, and a history of neoadjuvant therapy was associated with increased ANTXR1 expression in the endothelial cells of the tumor regions. Finally, above median expression of ANTXR1 in the tumor cells of the tumor regions was associated with significantly lower overall patient survival.

CONCLUSIONS

Our findings suggest that ANTXR1 is a promising candidate for preclinical and clinical evaluation for gastric adenocarcinoma immunotherapy.

Urgent Surgery for Gastric Adenocarcinoma: A Study of the National Cancer Database

BACKGROUND

Gastric adenocarcinoma is a leading cause of cancer death worldwide and, in the United States, can present emergently with upper GI hemorrhage, obstruction, or perforation. No large studies have examined how urgent surgery affects patient outcomes. This study examines the outcomes of urgent versus elective surgery for gastric cancer.

MATERIALS AND METHODS

Patients with gastric adenocarcinoma from the National Cancer Database from 2004 to 2015 were examined retrospectively. Patients with metastatic disease or incomplete data were excluded. Urgent surgery was defined as definitive surgery within 3 d of diagnosis. Univariate and multivariate analysis of patient factors, surgical outcomes, and oncologic data was performed. P-values <0.05 were statistically significant.

RESULTS

Of 26,116 total patients, 2964 had urgent surgery and 23,468 had elective surgery. Urgent surgery patients were significantly older, were female, were nonwhite, had higher pathologic stage, and were treated at a low-volume center. Urgent surgery was associated with decreased quality lymph node harvest (odds ratio [OR] 0.68 95% confidence interval {CI} [0.62, 0.74]), increased positive surgical margin (OR 1.48, 95% CI [1.32, 1.65]), increased 30-d mortality (OR 1.38, 95% CI [1.16, 1.65]), increased 90-d mortality (OR 1.30, 95% CI [1.14, 1.49]), and decreased overall survival (hazard ratio 1.21, 95% CI [1.15, 1.27]).

CONCLUSIONS

Urgent surgery for gastric cancer is associated with significantly worse outcomes than elective surgery. Stable patients requiring urgent surgical resection for gastric cancer may benefit from referral to a high-volume center for resection by an experienced surgeon. Patients undergoing urgent resection for gastric cancer should be referred to surgical and medical oncologists to ensure they receive appropriate adjuvant therapy and surveillance.

Discordance in HER2 status between primary gastric adenocarcinoma tumors and cells from the corresponding malignant effusions

BACKGROUND

Metastasis of gastric cancer commonly manifests as a malignant effusion, which presents an alternative cell source for human epidermal growth factor receptor 2 (HER2) status identification. This study aimed to compare HER2 status in primary gastric adenocarcinoma tumors and corresponding cell blocks prepared from malignant effusions (CB-MEs).

METHODS

HER2 status was retrospectively evaluated by immunohistochemistry (IHC) in primary gastric adenocarcinomas and paired pathologically confirmed CB-MEs of 45 patients. Silver in situ hybridization (SISH) was also performed in cases with IHC 2+ for primary gastric adenocarcinomas and above IHC 1+ for CB-MEs.

RESULTS

HER2 positivity was observed in 4.4% (2/45) of primary gastric adenocarcinomas and 6.7% (3/45) of CB-MEs. The HER2 concordance rate between primary gastric adenocarcinomas and CB-MEs was 88.9% (40/45) (κ = - 0.056). All five patients with HER2 positivity in the primary tumor or a CB-ME had a negative result in the corresponding paired sample. Of the 15 patients with two or more serially sampled CB-MEs, HER2 expression determined by IHC differed between each CB-ME in six (40%) patients, and all three patients with HER2 positivity in CB-MEs exhibited HER2 positivity in one of the serially sampled CB-MEs.

CONCLUSIONS

The HER2 positivity rate was very low in gastric cancer patients with malignant effusions. Our results suggest that HER2 positivity was discordant between the primary gastric adenocarcinoma and corresponding CB-MEs and among serially sampled CB-MEs. The possibility of detecting HER2 positivity can be improved if the primary gastric adenocarcinoma tumor as well as all the available CB-MEs from each patient are analyzed.

Time trends in the incidence of esophageal adenocarcinoma, gastric adenocarcinoma, and superficial esophagogastric junction adenocarcinoma

BACKGROUND

In Japan, the incidence of esophageal adenocarcinoma (EAC) and esophagogastric junction (EGJ) adenocarcinoma is expected to increase and that of gastric adenocarcinoma (GAC) is expected to decrease due to Westernization of the diet and the decreasing prevalence of Helicobacter pylori infection. However, few reports about these trends have included the latest data, and no reports about the time trend in the incidence of EGJ adenocarcinoma have focused on the etiologies (gastric cardia adenocarcinoma or EAC, including Barrett's adenocarcinoma). We therefore investigated the time trends in the incidence of these cancers by including the latest data.

METHODS

First, we investigated the time trends in EAC and GAC using population-based cancer registry data in Osaka Prefecture (1985-2014). We then investigated the time trend in superficial EGJ adenocarcinoma with clinicopathological features at Osaka International Cancer Institute (2006-2017).

RESULTS

From 1985 to 2014 in Osaka Prefecture, the incidence of EAC gradually increased in both sexes, while that of GAC in men did not significantly change and that in women decreased. The ratio of the EAC/GAC incidence increased 3.5 times in men and 1.8 times in women. In the secondary time trend survey for EGJ adenocarcinoma, the numbers of patients with endoscopic Barrett's esophagus and those without gastric mucosal atrophy increased, and the number of patients with lesions located above the EGJ line and histologically diagnosed as Barrett's adenocarcinoma increased.

CONCLUSIONS

The incidence of EAC and superficial EGJ adenocarcinoma with characteristics similar to those of EAC, including Barrett's adenocarcinoma, might be increasing.

Nomograms for predicting survival in patients with metastatic gastric adenocarcinoma who undergo palliative gastrectomy

BACKGROUND

Recently, evidence has emerged that palliative gastrectomy in patients with stage IV gastric cancer may offer some survival benefits. However, the decision whether to perform primary tumor surgery remains challenging for surgeons, and investigations into models that are predictive of prognosis are scarce. Current study aimed to develop and validate prognostic nomograms for patients with metastatic gastric adenocarcinoma treated with palliative gastrectomy.

METHODS

The development dataset comprised 1186 patients from the Surveillance, Epidemiology, and End Results Program who were diagnosed with metastatic gastric adenocarcinoma in 2004-2011, while the validation dataset included 407 patients diagnosed in 2012-2015. Variables were incorporated into a Cox proportional hazards model to identify independent risk factors for survival. Both pre- and postoperative nomograms for predicting 1- or 2-year survival probabilities were constructed using the development dataset. The concordance index (c-index) and calibration curves were plotted to determine the accuracy of the nomogram models. Finally, the cut-off value of the calculated total scores based on preoperative nomograms was set and validated by comparing survival with contemporary cases without primary tumor surgery.

RESULTS

Age, tumor size, location, grade, T stage, N stage, metastatic site, scope of gastrectomy, number of examined lymph node(s), chemotherapy and radiotherapy were risk factors of survival and were included as variables in the postoperative nomogram; the c-indices of the development and validation datasets were 0.701 (95% confidence interval [CI]: 0.693-0.710) and 0.699 (95% CI: 0.682-0.716), respectively. The preoperative nomogram incorporated age, tumor size, location, grade, depth of invasion, regional lymph node(s) status, and metastatic site. The c-indices for the internal (bootstrap) and external validation sets were 0.629 (95% CI: 0.620-0.639) and 0.607 (95% CI: 0.588-0.626), respectively. Based on the preoperative nomogram, patients with preoperative total score > 28 showed no survival benefit with gastrectomy compared to no primary tumor surgery.

CONCLUSIONS

Our survival nomograms for patients with metastatic gastric adenocarcinoma undergoing palliative gastrectomy can assist surgeons in treatment decision-making and prognostication.

Microbial carcinogenesis: Lactic acid bacteria in gastric cancer

While Helicobacter pylori is a fundamental risk factor, gastric cancer (GC) aetiology involves combined effects of microbial (both H. pylori and non-H. pylori), host and environmental factors. Significant differences exist between the gastric microbiome of those with gastritis, intestinal metaplasia and GC, suggesting that dysbiosis in the stomach is dynamic and correlates with progression to GC. Most notably, a consistent increase in abundance of lactic acid bacteria (LAB) has been observed in GC patients including Streptococcus, Lactobacillus, Bifidobacterium and Lactococcus. This review summarises how LAB can influence GC by a number of mechanisms that include supply of exogenous lactate -a fuel source for cancer cells that promotes inflammation, angiogenesis, metastasis, epithelial-mesenchymal transition and immune evasion-, production of reactive oxygen species and N-nitroso compounds, as well as anti-H. pylori properties that enable colonization by other non-H. pylori carcinogenic pathobionts.

Prognostic factors in patients with gastric adenocarcinoma using competing-risk analysis: a study of cases in the SEER database

Background: Accurate prognostic factors for gastric adenocarcinoma are still lacking in clinical practice, which contributes to inappropriate treatment. Applying the widely used Cox-proportional hazards model to describe survival trends and identify prognostic factors has limitations that result in a risk of bias. A competing-risk model was therefore adopted in this study to identify the significant prognostic factors and evaluate the cumulative incidence of cause-specific death for gastric adenocarcinoma, which can be used to guide clinical treatments. Methods: All of the cases analyzed in this study were extracted from the SEER (Surveillance, Epidemiology, and End Results) database. Using the competing risk approach, we calculated the cumulative incidence function (CIF) for cause-specific death and death from other causes at each time point. The Fine and Gray's proportional subdistribution hazard model was then applied in the univariate analysis and multivariate analysis to test the differences in CIF between different groups and obtain independent prognostic factors. Results: The univariate analysis showed that patients with characteristics of advanced pathology grade, lymph node involvement, and metastasis, were at risk of increasing cancer-specific mortality. Primary-site surgery, radiation with surgery, and chemotherapy, were associated with decreased cancer-specific mortality. The multivariate analysis showed that pathology grade, primary-site surgery, radiation with surgery, and chemotherapy, could significantly affect the cancer-specific mortality and were independent prognostic factors in patients with gastric adenocarcinoma. Conclusions: Using a competing-risk model, this study obtained more-accurate estimates for the cumulative incidence of cancer-specific death and identified the prognostic factors more accurately for gastric adenocarcinoma.

MMP7 Induces T-DM1 Resistance and Leads to the Poor Prognosis of Gastric Adenocarcinoma via a DKK1-Dependent Manner

BACKGROUND

Gastric adenocarcinoma is one of the most common and lethal cancer types and is known as the second leading cause of cancer-related death of Asian adults, early diagnosis based on either pathology or molecular biology could be one of the most efficient ways to improve the outcomes of gastric adenocarcinoma patients.

METHODS

Quantitative Real-Time PCR and Western-blot were used in detection of mRNA and protein expression. Lentivirus infection was used to overexpression or knock down target gene. Alarma blue assay was used to monitor cells proliferation. Flow cytometry analysis was performed to test protein expression and apoptosis level. Immunohistochemistry was used to identify protein expression in tissue. Statistical differences between two groups are evaluated by two-tailed t-tests. The comparison among multiple groups is performed by one-way Analysis of Variance (ANOVA) followed by Dunnett's posttest. The statistical significance of the Kaplan-Meier survival plot is determined by log-rank analysis.

RESULTS

MMP7 as one of the most up-regulated genes in T-DM1 resistant NCI-N87 gastric adenocarcinoma cells compared to matched naïve cell lines. T-DM1 resistant NCI-N87 cell lines by exposed to T-DM1 in vitro. Exogenous overexpression of MMP7 promotes T-DM1 resistance and tumor growth in NCI-N87 cell lines while MMP7 knockdown enhanced sensitivity to T-DM1 in T-DM1 resistant NCI-N87 cell lines established previously. MMP7 was enriched in high WHO grade GC samples and implies poor outcomes for these patients. DKK1 as one of the most correlated genes to MMP7 in gastric adenocarcinoma and knock-down of DKK1 or inhibition of Wnt/β-catenin pathway led to a decreased expression of MMP7 and resistance to T-DM1.

CONCLUSION

DKK1 and Wnt/β-catenin-dependent activation of MMP7 induces T-DM1 resistance and leads to the poor prognosis of gastric adenocarcinoma, which might be a novel potential therapeutical target for T-DM1 resistant gastric adenocarcinoma.

Gastrectomy Alone or in Combination With Hepatic Resection in the Management of Liver Metastases From Gastric Cancer: A Systematic Review Using an Updated and Cumulative Meta-Analysis

Background

Recent studies have demonstrated that hepatectomy in patients with synchronous hepatic gastric metastases may improve survival in certain patients. This study aimed to evaluate survival benefits of gastrectomy plus hepatectomy versus gastrectomy alone in patients with hepatic gastric metastases.

Methods

Studies were identified by a systematic search of Embase, PubMed, Cochrane Library, and Google Scholar databases. Traditional and cumulative meta-analyses were used to monitor the evidence over time.

Results

Eleven studies which included 861 patients compared gastrectomy plus hepatic resection in 349 patients with gastrectomy alone in 512 patients. Overall significantly better survival rates of 1, 2, 3, and 5 years were demonstrated for patients who underwent gastrectomy plus hepatic resection compared to patients who under underwent gastrectomy alone ((hazard ratio (HR) = 0.52 (0.39, 0.69), P < 0.001), (HR = 0.85 (0.74, 0.97), P = 0.01), (HR = 0.80 (0.72, 0.90), P = 0.003), (HR = 0.83 (0.78, 0.90), P < 0.001), respectively).

Conclusions

Carefully selected patients with hepatic gastric metastases may benefit from hepatic resection.

Gene expression patterns of COX-1, COX-2 and iNOS in H. Pylori infected histopathological conditions

BACKGROUND

Research indicates that Helicobacter pylori can inflict severe histological damage through the modulation of host-related genes. The current study investigated the effect of H. pylori genotypes in the outcome of disease, and the expression of anti-apoptotic related genes, COX-1, COX-2, and iNOS genes in benign, pre-malignant, and malignant lesions of gastric carcinogenesis.

MATERIALS AND METHODS

Tissue samples from H. pylori positive patients were graded based on the genotype of the infected H. pylori strain. Expression of COX-1, COX-2 and iNOS was assessed using a combination of real-time PCR and immunohistochemistry.

RESULTS

Gene expression studies confirmed that COX-2 and iNOS expression was highly and selectively induced in epithelium with premalignant changes such as atrophic conditions, metaplasia and dysplasia, suggesting an important role of these genes in the sequence to gastric carcinoma of the intestinal type. Furthermore, the expression of COX-2 and iNOS was also dependent on the genotype of H. pylori and subjects with genotype-1 exhibited significantly higher expressions of COX-2 and iNOS compared to other genotypes. Comparison of the expression levels among infected and uninfected individuals demonstrated significant difference in the expression pattern of COX-2 gene whereas iNOS expression was found only in subjects infected H. pylori (p < 0.001). Immunohistochemical staining showed 1.5619 folds higher propensity of COX-2 and 3.2941 folds higher intensity of iNOS expression in subjects infected with H. pylori genotype 1.

CONCLUSION

The up-regulation of COX-2 and iNOS was associated with the genotype of the H. pylori strain and the presence of certain genotype may greatly affect early events during carcinogenesis.

Prognostic significance of Human epidermal growth factor receptor-2 expression in patients with resectable gastric adenocarcinoma

BACKGROUND

The purpose of this study was to investigate the correlation between human epidermal growth factor receptor 2 (HER2) overexpression and clinicopathologic factors and overall survival rate in patients who underwent curative gastrectomy for gastric adenocarcinoma.

METHODS

Among patients who underwent curative gastrectomy for gastric adenocarcinoma at Inje University Paik Hospital from January 2012 to December 2015, 782 patients underwent an immunohistochemical analysis to evaluate HER2 expression levels. Clinicopathologic records that were collected from a gastric cancer database were retrospectively reviewed to identify clinicopathologic factors and survival rates of the patients.

RESULTS

HER2 overexpression was detected in 166 patients (21.2%). There was a statistically significant correlation between HER2 expression level and sex (p = 0.013), histologic differentiation (p < 0.001), Lauren classification (p < 0.001), and T pathologic stage (p = 0.022). There were no statistically significant relationships between HER2 expression level and overall 5-year survival rate (p = 0.775) and overall 5-year survival rate of gastric adenocarcinoma classified according to the TNM stage (stage I: p = 0.756, stage II: p = 0.571, stage III: p = 0.704). The HER2 expression level was not affected by the overall 5-year survival rate in the uni- and multivariate analyses.

CONCLUSIONS

In this study, the HER2 overexpression rate in gastric adenocarcinoma was 21.2% and was observed in well- and moderately differentiated types according to histologic differentiation, intestinal type according to the Lauren classification, male, and low T stage. There was no correlation between HER2 expression level and overall 5-year survival rate, and HER2 expression level was not associated with independent prognostic factors.

Gastric adenocarcinoma of fundic gland type after Helicobacter pylori eradication: A case report

BACKGROUND

Gastric adenocarcinoma of fundic gland type (GA-FG) has recently been proposed as a novel histological type of gastric cancer.

CASE SUMMARY

We report a case of GA-FG in a 77-year-old Chinese woman with epigastric distention who was referred to endoscopy for the management of an incidentally found submucosal tumor-like elevated lesion in the lower part of the gastric body. The tumor occurred after Helicobacter pylori (H. pylori) eradication therapy without long-term use of proton pump inhibitors. Complete and curable removal of the tumor was performed by endoscopic submucosal dissection. Histopathological findings showed numerous cells with basophilic cytoplasm and mildly atypical nuclei-like chief cells of the fundic gland. The tumor was observed to have the so-called “endless glands” pattern of the well-differentiated mixed phenotype. A safe resection margin without lymphatic and venous invasion was observed. As the tumor occurred after H. pylori eradication therapy, it is unknown whether there was a relationship with H. pylori eradication. The patient will be followed up by periodic gastroscopic observation.

CONCLUSION

In conclusion, we report a case of GA-FG after H. pylori eradication therapy without long-term proton pump inhibitors use. Further analysis of similar cases will reveal the clinical behavior of GA-FG.

The therapeutic potential of metformin in gastric cancer

Metformin is a biguanide molecule used since 1957 to treat type 2 diabetes patients. In addition to its hypoglycemic effects, epidemiological studies have shown that metformin can be associated with a decrease in cancer development risk in diabetic populations. Thus, since 2005 this molecule is largely studied for its antitumoural properties in different types of cancer. The potential antitumoural effect of metformin in gastric cancer has been poorly studied. Here, we detailed the different described mechanisms implicated in the antitumoural effect of metformin in gastric cancer, from the signalling pathways to the functional effects on gastric cancer cell lines and gastric cancer stem cells.

The combined expressions of B7H4 and ACOT4 in cancer-associated fibroblasts are related to poor prognosis in patients with gastric carcinoma

B7H4 is a member of the B7 family, which is expressed on antigen-presenting cells (APCs) and which negatively regulates the immune response of T cells through the inhibition of their proliferation, cytokine production, and cell cycle progression. Acyl-CoA thioesterase 4 (ACOT4) is an isoform of the ACOTs family that catalyzes the hydrolysis of fatty acyl-CoA to CoA-SH and free fatty acids. An abnormal metabolism of lipids and fatty acids is observed during tumor progression. In our study, a tissue microarray was constructed from 288 cases of gastric adenocarcinoma (GC). ACOT4 expression in cancer-associated fibroblasts (CAFs) and B7H4 expression in cancer tissues were analyzed by immunohistochemistry. The correlations among B7H4 in GC cells, ACOT4 in CAFs, and survival were analyzed. The results showed that the expression rate of B7H4 in tumor cells and ACOT4 in CAFs in 288 tissues was 71.9% (207/288) and 26.4% (76/288), respectively, and a Kaplan-Meier survival analysis showed that a low expression of ACOT4 in fibroblasts was positively correlated with poor survival. However, in a subgroup showing a high ACOT4 expression, the overall survival rate was associated with a high expression of B7H4 and correlated with poor prognosis in GC. In conclusion, ACOT4 expression in CAFs could be an independent prognostic factor for GC patients, and the co-expression with B7H4 in cancer tissues was significantly correlated with GC patients' prognosis. This evidence can represent a comprehensive prediction and a targeted therapy for gastric cancer patients. Tumor immunotherapy targeting might be affected by tumor microenvironment metabolism.