Adjuvant and/or neoadjuvant therapy for gastric cancer? A perspective review

Preoperatively predicting the lymph node metastasis and prognosis for gastric cancer patients

The preoperative distinguishment of lymph nodes (LN) with metastasis plays a pivotal role in guiding the surgical extension for gastric cancer (GC). We aim to identify the preparative risk factors for LN metastasis in GC patients. We retrospectively reviewed 424 patients who underwent radical GC resection in our medical center between Jan 2011 and Dec 2018. Multivariate logistic regression was employed to identify risk factors for LN metastasis, while multivariate COX regression was utilized to evaluate prognostic factors. The median overall survival of patients with or without LN metastases was 31 and 58 months, respectively. In multivariate analysis, lower albumin (OR = 0.512; P = 0.004) and prealbumin (OR = 0.367, P = 0.001) and higher CEA (OR = 3.178, P < 0.001), CA199 (OR = 2.278, P = 0.002) and platelets (OR = 1.697, P = 0.017) were found to be significantly associated with LN metastasis. In survival analysis, older age (HR = 1.712), larger tumors (HR = 1.082), higher D-dimer (HR = 1.561) and CA199 (HR = 1.553), advanced staging (stage II, HR = 3.446; stage III-IV, HR = 11.089), lower prealbumin levels (lower level for reference, HR = 0.63), and absence of adjuvant chemotherapy (HR = 0.396) was discovered to be associated with poorer overall survival (all P < 0.05). In conclusion, our results demonstrated that preoperative prealbumin-bound tumor markers can effectively predict LN metastasis. Additionally, prealbumin was found to possess prognostic value as well.

Claudin-18.2 testing and its impact in the therapeutic management of patients with gastric and gastroesophageal adenocarcinomas: A literature review with expert opinion

Claudin-18.2 (CLDN18.2) is a member of the tight junction protein family and is a highly selective biomarker with frequent abnormal expression during the occurrence and development of various primary malignant tumors, including gastric cancer (GC) and esophago-gastric junction adenocarcinomas (EGJA). For these reasons, CLDN18.2 has been investigated as a therapeutic target for GC/EGJA malignancies. Recently, zolbetuximab has been proposed as a new standard of care for patients with CLDN18.2-positive, HER2-negative, locally advanced and metastatic GC/EGJA. The use of CLDN18 IHC assays to select patients who might benefit from anti-CLDN18.2 therapy is currently entering clinical practice. In this setting, pathologists play a central role in therapeutic decision-making. Accurate biomarker assessment is essential to ensure the best therapeutic option for patients. In the present review, we provide a comprehensive overview of available evidence on CLDN18.2 testing and its impact on the therapeutic management of patients with GC/EGJA, as well as some practical suggestions for CLDN18.2 staining interpretation and potential pitfalls in the real-world setting.

Fibrinogen-to-Lymphocyte Ratio Was an Independent Predictor of Lymph Node Metastasis in Patients with Clinically Node-Negative Advanced-Stage Gastric Cancer

Purpose

Various hematological indicators have been reported to predict lymph node metastasis (LNM) in gastric cancer (GC) patients, but the relationship between FLR and LNM has not been studied. Therefore, the aim of this study was to evaluate the role of preoperative fibrinogen-to-lymphocyte ratio (FLR) in predicting LNM in patients with clinically node-negative (cN0) advanced gastric cancer (AGC).

Patients and Methods

We retrospectively reviewed 571 eligible patients with primary AGC adenocarcinoma who underwent radical gastrectomy (discovery cohort). Patients were divided into high and low FLR groups according to the optimal cutoff value determined by Youden index. FLR is an independent predictor of LNM determined by logistic regression and validated in the validation cohort of 207 patients. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive value of FLR for LNM. The nonlinear relationship between FLR and LNM risk was assessed using restricted cubic spline. Sensitivity analyses were performed according to FLR quartiles to further assess the robustness of the results. The nomogram was built based on FLR and clinicopathological characteristics, and was evaluated by calibration curves, ROC curve analysis and decision curve analysis.

Results

In the discovery cohort, the area under the curve (AUC) value for FLR to predict LNM was 0.592. There is a linear relationship between the FLR value and the risk of LNM, and the risk of LNM increased with FLR value. High FLR level is an independent risk factor for LNM, and the results of sensitivity analysis robust this finding. The nomogram for individual risk assessment performed well. Furthermore, we verified the FLR was an independent predictor of LNM in the validation cohort.

Conclusion

FLR was an independent predictor of LNM in patients with cN0 AGC.

Association between neutrophil-lymphocyte ratio and lymph node metastasis in gastric cancer: A meta-analysis

INTRODUCTION AND AIM

The prognostic role of neutrophil to lymphocyte ratio (NLR) has been explored extensively in the literature. The aim of this meta-analysis was to evaluate the link between NLR and lymph node metastasis in gastric cancer. A method for increasing specificity and sensitivity of pre-treatment staging has implications on treatment algorithms and survival.

SEARCH STRATEGY

The relevant databases were searched as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart. After selection, 12 full text articles that met the inclusion criteria were included for quantitative analysis. 2 × 2 squares were generated using lymph node positive/negative, and NLR high/low data. The effect size for each study was calculated using the DerSimonian-Laird random effects model. P values were calculated using the chi-square method. Finally publication bias was evaluated. All statistics were calculated using R Studio.

RESULTS

Meta-analysis showed a 1.90 times (odds ratio, with 95% CI 1.52-2.38) increase in risk of positive lymph node status with high neutrophil to lymphocyte ratio. This has significant implications for cancer screening and staging, as NLR is a highly reproducible, cost-effective, and widely available prognostic factor for gastric cancer patients. Additionally, high or low NLR values may have implications for management pathways. Patients with lymph node metastasis can be offered neoadjuvant chemotherapy, avoiding salvage therapy in the form of adjuvant chemoradiotherapy, which is poorly tolerated.

CONCLUSION

This meta-analysis shows an association between NLR and positive lymph node status in gastric cancer patients with implications for staging, as well as preoperative personalisation of therapy.

Correlative Analysis Between Adverse Events of Preoperative Chemotherapy and Postoperative Complications of Gastric Cancer

Background and Objectives: This study aims to explore the safety of preoperative chemotherapy and clarify whether preoperative chemotherapy with oxaliplatin + S-1 (SOX) regimen and its adverse events are associated with higher risks of postoperative complications. Methods: We included consecutive patients with gastric cancer who underwent gastrectomy in our department between July 1 2018, and January 31 2020. Patients with preoperative SOX regimen chemotherapy were included in the analysis. Results: In the 343 included patients, 77 cases underwent preoperative chemotherapy. In total, surgical complications were found in 117 patients (34.1%), and there was no significant difference between the patients with and without preoperative chemotherapy before and after propensity score matching (p > 0.05, respectively). Multivariate analysis showed that preoperative comorbidities (p = 0.026) and the preoperative cT4b (p = 0.028) were independent risk factors in postoperative complications. In patients with preoperative chemotherapy, neither the occurrence of adverse events nor their severity was associated with postoperative complications (p > 0.05). However, the patients who received five to six cycles were more prone to postoperative complications than those who received three to four cycles (62.5 vs. 27.9%, OR = 4.306, 95% Cl = 1.282-14.464, p = 0.018). Conclusions: Occurrence of postoperative complications was not influenced by preoperative SOX chemotherapy. However, increased cycles of chemotherapy may lead to higher incidence of postoperative complications.

Optimal care and survival for signet-ring cell and non-signet-ring cell gastric cancer are more achievable at academic cancer centers

BACKGROUND

Western literature lacks large-scale population studies comparing the influence of academic and high-volume (HV) versus low-volume (LV) cancer centers on gastric cancer oncologic outcomes.

METHODS

The National Cancer Database from 2004 to 2016 was used.

RESULTS

22871 patients were studied. Patients with stage III signet-ring cell gastric carcinoma (SRGC) received neoadjuvant treatment (NAT) more frequently at academic and HV comprehensive cancer centers (OR: 4.27 and 2.42; p < 0.0001 and 0.009) compared to community centers. Patients with stage III non-SRGC (NSRGC) had a 2.4 times higher odds of receiving NAT at academic centers. The R1 resection rate for NSRGC was lower at academic centers (OR: 0.67; p = 0.0018). Lymph node harvest ≥15 nodes was 1.6 and 1.9 times higher at academic centers for NSRGC and SRGC, respectively. Patients treated at academic centers had a significantly improved overall survival (OS).

CONCLUSIONS

Treatment at academic centers is associated with significant improvements in oncologic metrics and OS.

LncRNA HOTAIR promotes the growth and metastasis of gastric cancer by sponging miR-1277-5p and upregulating COL5A1

BACKGROUND

Emerging studies have shown that HOTAIR acts as an oncogene in gastric cancer (GC). However, its role in the extracellular matrix and in tumor immune infiltration remains unknown.

METHODS

HOTAIR and COL5A1 levels were analyzed by bioinformatics analysis and validated by qRT-PCR, western blotting and immunohistochemistry assays. The regulatory relationships between components of the HOTAIR/miR-1277-5p/COL5A1 axis and the role of this axis in GC were predicted by bioinformatics analysis, and validated by in vitro and in vivo experiments. The correlation between COL5A1 and GC immune infiltration was assessed by bioinformatics analysis and a COL5A1-based predictive nomogram was established using the Stomach Adenocarcinoma dataset from The Cancer Genome Atlas.

RESULTS

We found that HOTAIR and COL5A1 were overexpressed in GC compared to normal controls, which predicted poor prognosis. The regulatory relationship of the HOTAIR/miR-1277-5p/COL5A1 axis in GC was demonstrated, and HOTAIR and COL5A1 were found to promote GC growth while miR-1277-5p exerted the reverse effects. In addition, COL5A1 was negatively associated with tumor purity but positively associated with immune infiltration, which suggested that COL5A1-mediated GC growth may be partially mediated by the regulation of immune infiltration. Additionally, the established COL5A1-based nomogram showed that COL5A1 can serve as a prognostic biomarker in GC.

CONCLUSIONS

HOTAIR regulates GC growth by sponging miR-1277-5p and upregulating COL5A1, and COL5A1-mediated GC cell proliferation may be mediated by effects on the tumor microenvironment, which provides novel targets for GC treatment.

Phosphoproteomic analysis identifies CLK1 as a novel therapeutic target in gastric cancer

BACKGROUND

Phosphorylation is an important regulatory mechanism of protein activity in cells. Studies in various cancers have reported perturbations in kinases resulting in aberrant phosphorylation of oncoproteins and tumor suppressor proteins.

METHODS

In this study, we carried out quantitative phosphoproteomic analysis of gastric cancer tissues and corresponding xenograft samples. Using these data, we employed bioinformatics analysis to identify aberrant signaling pathways. We further performed molecular inhibition and silencing of the upstream regulatory kinase in gastric cancer cell lines and validated its effect on cellular phenotype. Through an ex vivo technology utilizing patient tumor and blood sample, we sought to understand the therapeutic potential of the kinase by recreating the tumor microenvironment.

RESULTS

Using mass spectrometry-based high-throughput analysis, we identified 1,344 phosphosites and 848 phosphoproteins, including differential phosphorylation of 177 proteins (fold change cut-off ≥ 1.5). Our data showed that a subset of differentially phosphorylated proteins belonged to splicing machinery. Pathway analysis highlighted Cdc2-like kinase (CLK1) as upstream kinase. Inhibition of CLK1 using TG003 and CLK1 siRNA resulted in a decreased cell viability, proliferation, invasion and migration as well as modulation in the phosphorylation of SRSF2. Ex vivo experiments which utilizes patient's own tumor and blood to recreate the tumor microenvironment validated the use of CLK1 as a potential target for gastric cancer treatment.

CONCLUSIONS

Our data indicates that CLK1 plays a crucial role in the regulation of splicing process in gastric cancer and that CLK1 can act as a novel therapeutic target in gastric cancer.

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.

Peripheral Venous Blood Platelet-to-Lymphocyte Ratio (PLR) for Predicting the Survival of Patients With Gastric Cancer Treated With SOX or XELOX Regimen Neoadjuvant Chemotherapy

Background:

Inflammation plays an important role in tumor progression. Predicting survival is remarkably difficult in patients with gastric cancer receiving neoadjuvant chemotherapy. The aim of the present study is to investigate the potential prognostic significance of the platelet-to-lymphocyte ratio in patients with gastric cancer receiving S-1 plus oxaliplatin or oxaliplatin and capecitabine regimen.

Methods:

Ninety-one patients with gastric cancer treated with neoadjuvant chemotherapy were enrolled in this study and then underwent operation. The optimal cutoff value was calculated using receiver-operating characteristic curve analyses. The optimal cutoff value of platelet-to-lymphocyte ratio was divided into low platelet-to-lymphocyte ratio <162 group and high platelet-to-lymphocyte ratio ≥162 group. Kaplan-Meier method and log-rank test were used to analyze the survival curves. The independent prognostic factors and prognostic value of the platelet-to-lymphocyte ratio were assessed by univariate and multivariate Cox proportional hazards regression model. The toxicity was evaluated according to the National Cancer Institute Common Toxicity Criteria.

Results:

Kaplan-Meier analyses revealed that patients with low platelet-to-lymphocyte ratio correlated remarkably with better mean disease-free survival and mean overall survival than those with high platelet-to-lymphocyte ratio (mean disease-free survival 47.33 and 33.62 months, respectively; mean overall survival 51.21 and 36.80 months, respectively). The results demonstrated that platelet-to-lymphocyte ratio had prognostic significance using the cutoff value of 162 on disease-free survival and overall survival, and the mean disease-free survival and overall survival time for patients with low platelet-to-lymphocyte ratio were longer than those with high platelet-to-lymphocyte ratio. Meanwhile, patients with gastric cancer who had lower platelet-to-lymphocyte ratio had longer 1-, 3-, and 5-year rates of disease-free survival and overall survival. Moreover, patients with low platelet-to-lymphocyte ratio had longer mean disease-free survival and overall survival than those with high platelet-to-lymphocyte ratio in receiving S-1 plus oxaliplatin or oxaliplatin and capecitabine regimen.

Conclusions:

The preoperative platelet-to-lymphocyte ratio may be a promising and convenient prognostic biomarker for patients gastric cancer receiving S-1 plus oxaliplatin or oxaliplatin and capecitabine regimen neoadjuvant chemotherapy. It may be useful to help the doctors identify the high-risk patients for taking efficient treatment strategy decisions.

Unnecessity of lymph node regression evaluation for predicting gastric adenocarcinoma outcome after neoadjuvant chemotherapy

BACKGROUND

Neoadjuvant chemotherapy has been applied worldwide to improve the survival of patients with gastric adenocarcinoma (GAC). The evaluation of histological regression in primary tumors is valuable for predicting prognosis. However, the prognostic effect of regression change in lymph nodes (LNs) remains unclear.

AIM

To confirm whether the evaluation of regression change in LNs could predict the prognosis of GAC patients who received neoadjuvant chemotherapy followed by surgery.

METHODS

In this study, we evaluated the histological regression of resected LNs from 192 GAC patients (including those with esophagogastric junction adenocarcinoma) treated with neoadjuvant chemotherapy. We classified regression change and residual tumor in LNs into four groups: (A) true negative LNs with no evidence of a preoperative therapy effect, (B) no residual metastasis but the presence of regression change in LNs, (C) residual metastasis with regression change in LNs, and (D) metastasis with minimal or no regression change in LNs. Correlations between regression change and residual tumor groups in LNs and regression change in the primary tumor, as well as correlations between regression change in LNs and clinicopathological characteristics, were analyzed. The prognostic effect of regression change and residual tumor groups in LNs was also analyzed.

RESULTS

We found that regression change and residual tumor groups in LNs were significantly correlated with regression change in the primary tumor, tumor differentiation, ypT stage, ypN stage, ypTNM stage, lymph-vascular invasion, perineural invasion and R0 resection status. Regression change and residual tumor groups in LNs were statistically significant using univariate Cox proportional hazards analysis, but were not independent predictors. For patients who had no residual tumor in LNs, the 5-year overall survival (OS) rates were 67.5% in Group A and 67.4% in Group B. For the patients who had residual tumors in LNs, the 5-year OS rates were 28.2% in Group C and 39.5% in Group D. The patients in Groups A+B had a significantly better outcome than the patients in Groups C+D (P < 0.01). No significant differences in survival were found between Groups A and B, or between Groups C and D.

CONCLUSION

The existence of residual tumor in LNs, rather than regression change in LNs, is useful for predicting the prognosis after neoadjuvant chemotherapy in GAC patients. In practice, it may not be necessary to report regression change in LNs.

Combined perioperative EOX chemotherapy and postoperative chemoradiotherapy for locally advanced gastric cancer

Currently, adjunctive therapy for gastric cancer is not standardized worldwide and the most effective combination of different modalities has not been clearly determined. The aim of the present study was to retrospectively analyze the efficacy and toxicity of the combination of perioperative epirubicin, capecitabine and oxaliplatin (EOX) chemotherapy and postoperative concurrent chemoradiotherapy in the treatment of locally advanced gastric cancer. A total of 41 patients with locally advanced gastric cancer who had undergone perioperative EOX chemotherapy and surgical resection followed by chemoradiotherapy, were assessed. The perioperative EOX regimen consisted of 50 mg/m² epirubicin and 130 mg/m² oxaliplatin on day 1, with 625 mg/m² capecitabine administered twice daily on days 1-21. The perioperative regimen was repeated 2-3 times every 3 weeks. After complete resection following the perioperative EOX regimen, concurrent chemoradiotherapy with capecitabine (4,500 cGy in daily fractions of 180 cGy administered 5 days per week for 5 weeks, with 625 mg/m² capecitabine twice daily during radiotherapy) and 2 cycles of the EOX regimen 4 weeks after radiotherapy, were performed. In total, 30/41 patients (73.2%) completed all the planned treatments, including perioperative chemotherapy, surgical resection and chemoradiotherapy. The effective rate of preoperative chemotherapy (partial and complete response) was 56.1%; 30/41 patients received R0 resection, and the overall 3-year survival rate was 57.7%. Grade 3/4 gastrointestinal toxicity (nausea/vomiting) occurred in 22% of the patients, while 18 patients (43.9%) developed grade 3/4 hematological toxicity (granulocytopenia). The results of the present study indicated that the combination of perioperative EOX chemotherapy and postoperative concurrent chemoradiotherapy is feasible and effective for locally advanced gastric cancer.

Role of Δ133p53 isoform in NF-κB inhibitor PDTC-mediated growth inhibition of MKN45 gastric cancer cells

AIM

To investigate the role of Δ133p53 isoform in nuclear factor-κB (NF-κB) inhibitor pyrrolidine dithiocarbamate (PDTC)-mediated growth inhibition of MKN45 gastric cancer cells.

METHODS

The growth rate of MKN45 cells after treatment with different concentrations of only PDTC or PTDC in combination with cisplatin was detected by the CCK-8 assay. mRNA expression levels of Δ133p53, p53β, and the NF-κB p65 subunit and p65 protein levels were detected by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence, respectively. Growth of MKN45 cells was significantly inhibited by PDTC alone in a dose-dependent manner (P < 0.01). Moreover, the inhibitory effect of cisplatin was remarkably enhanced in a dose-dependent manner by co-treatment with PDTC (P < 0.01).

RESULTS

RT-PCR analysis revealed that mRNA expression of p65 was curbed significantly in a dose-dependent manner by treatment with only PDTC (P < 0.01), and this suppressive effect was further enhanced when co-treated with cisplatin (P < 0.01). With respect to the other p53 isoforms, mRNA level of Δ133p53 was significantly reduced in a dose-dependent manner by treatment with only PDTC or PTDC in combination with cisplatin (P < 0.01), whereas p53β mRNA expression was not altered by PDTC treatment (P > 0.05). A similar tendency of change in p65 protein expression, as observed for the corresponding mRNA, was detected by immunofluorescence analysis (P < 0.01). Pearson correlation analysis demonstrated that Δ133p53 and p65 mRNA expression levels were positively related, while no significant relationship was observed between those of p65 and p53β (r = 0.076, P > 0.01).

CONCLUSION

Δ133p53 isoform (not p53β) is required in PDTC-induced inhibition of MKN45 gastric cancer cells, indicating that disturbance in the cross-talk between p53 and NF-κB pathways is a promising target in pharmaceutical research for the development of treatment strategies for gastric cancer.

Effect of p53β on human gastric cancer cells treated with recombinant mutated human TNF and cisplatin

The present study aimed to investigate the role of tumour protein 53 isoform b (p53β) on human gastric cancer (GC) cell lines treated with recombinant mutated human tumour necrosis factor (rmhTNF) and cisplatin. The Cell Counting Kit‑8 assay was used to assess growth in the GC cell lines MKN45 and SGC7901, following treatment with rmhTNF in the presence or absence of cisplatin. Levels of p53β and bcl‑2 apoptosis regulator (bcl‑2) mRNA were assessed using reverse transcription‑polymerase chain reaction. The results demonstrated that growth was significantly inhibited by either cisplatin or rmhTNF treatments alone in MKN45 cells, and combination treatment with cisplatin and rmhTNF had a synergistic effect on growth inhibition of MKN45 cells. Notably, these observations were not evident in SGC7901 cells, where a mutant form of p53 is present. Treatment of MKN45 cells with rmhTNF did not affect bcl‑2 or p53β mRNA expression levels. However, treatment of MKN45 cells with cisplatin induced upregulation of p53β and downregulation of bcl-2 mRNA expression levels, and these effects were enhanced by combination treatment with rmhTNF. Pearson correlation analysis revealed a negative correlation between the expression of p53β and bcl‑2 mRNA, and a negative correlation between bcl-2 mRNA expression and the inhibition of cell growth. In conclusion, the inhibitory effect of cisplatin on the growth of MKN45 GC cells was enhanced by rmhTNF via unknown mechanisms that involved p53β, indicating that p53β may be an appropriate therapeutic target for the treatment of GC.

Comparison of five tumor regression grading systems for gastric adenocarcinoma after neoadjuvant chemotherapy: a retrospective study of 192 cases from National Cancer Center in China

BACKGROUND

Neoadjuvant chemotherapy has been increasingly practiced on gastric cancer (GC), and histological evaluation to predict outcome is urgent in clinical practice. There are five classic tumor regression grading (TRG) systems, including Mandard-TRG system, the Japanese Gastric Cancer Association (JGCA)-TRG system, College of American Pathologists (CAP)-TRG system, China-TRG system and Becker-TRG system.

METHODS

Totally, 192 patients of gastric adenocarcinoma (including adenocarcinoma of the esophagogastric junction) treated by neoadjuvant chemotherapy and surgery were evaluated using the above five TRG systems. The clinicopathological characteristics were also assessed. The correlation among TRG systems, clinicopathological characteristics and prognosis were analyzed.

RESULTS

All the five TRG systems were significantly correlated with differentiation, postsurgical T category, postsurgical N category, American Joint Committee on Cancer (AJCC) stage, lymph-vascular invasion, perineural invasion, as well as tumor size. All the five TRG systems were statistically significant in univariate Cox survival analysis. However, only postsurgical T category, postsurgical N category and R0 resection were independent in multivariate Cox survival analysis. The tight correlation between the TRG systems and other characteristics such as postsurgical stage might affect the independent prognostic role of the TRG systems. As compared with other TRG systems, the hazard ratio of no/slightly response in both Mandard TRG system and JGCA TRG system revealed higher hazard of death and disease progression than that of severe response when using univariate Cox survival analysis. The median survival time of complete response and nearly complete response were much longer than that of partial response, all classified by Mandard-TRG system. This could help clinicians predict prognosis more reasonably than JGCA-TRG which does not have the category of nearly complete response.

CONCLUSION

We recommend Mandard-TRG system for GC after neoadjuvant chemotherapy due to its better prediction of prognosis.

Long Noncoding RNA Taurine-Upregulated Gene 1 Promotes Cell Proliferation and Invasion in Gastric Cancer via Negatively Modulating miRNA-145-5p

Long noncoding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) is involved in the development and carcinogenesis of various tumors, suggesting the diagnostic potential of TUG1 in these cancers. However, the exact role of TUG1 and its underlying mechanism in gastric cancer (GC) remain unknown. In this study, the expression of TUG1 and miR-145-5p in GC cell lines and nonmalignant gastric epithelial cell lines was detected by qRT-PCR. BGC-823 and SGC-7901 cells were transfected with si-TUG1, pcDNA 3.1-TUG1, miR-145-5p mimics, or matched controls. The biological function of TUG1 and miR-145-5p in GC cell proliferation and invasion in vitro and tumor growth in vivo was investigated by MTT assay, Transwell invasion assay, and tumor xenograft experiments. The regulating relationship between TUG1 and miR-145-5 was confirmed by luciferase reporter assay. The results showed that TUG1 was significantly overexpressed and miR-145-5p was dramatically downregulated in GC cell lines. TUG1 knockdown strikingly inhibited cell proliferation and invasion in vitro and markedly suppressed tumor growth in vivo. Furthermore, TUG1 could directly bind to miR-145-5p and repress miR-145-5p expression. TUG1 overexpression significantly relieved the inhibition on GC cell proliferation and invasion in vitro and tumor growth in vivo, mediated by miR-145-5p overexpression. In conclusion, TUG1 promotes cell proliferation and invasion in GC via negatively modulating miRNA-145-5p, which undoubtedly contributes to understanding the mechanism of GC occurrence and development.

Updated evidence on adjuvant treatments for gastric cancer

Gastric cancer is one of the main causes of cancer-related deaths worldwide. Even when diagnosed as a localized disease and resected with the intent to cure, recurrences frequently arise due to undetected or invisible micrometastases. Importantly, several proposed multimodal strategies to eliminate micrometastases have met some clinical success. However, while pivotal Phase III clinical trials comparing adjuvant therapies with surgery alone have confirmed the overall benefit of adjunctive treatments in patients with locally advanced gastric cancer, further improvement in postoperative outcomes is required, particularly in stage III disease. This review presents the current status of multimodal treatment strategies, with a particular focus on unresolved issues, based on updated literature searches and analysis of clinical trial databases.

Proposal of the Coagulation Score as a Predictor for Short-Term and Long-Term Outcomes of Patients with Resectable Gastric Cancer

BACKGROUND

Systemic hemostasis and thrombosis activation has been implicated in tumor progression and metastasis. This study aimed to investigate the use of coagulation factors as a novel prediction method for postoperative outcomes after curative gastrectomy in patients with stage II/III gastric cancer (GC).

METHODS

Overall, 126 patients with stage II/III GC who underwent gastrectomy between May 2003 and February 2016 were eligible for inclusion in the study. We retrospectively evaluated the predictive value of preoperative platelet count and plasma fibrinogen and d-dimer levels, and coagulation score (0: fibrinogen and d-dimer both below upper limits; 1: either fibrinogen or d-dimer over upper limits; 2: both fibrinogen and d-dimer over upper limits) for short- and long-term outcomes.

RESULTS

Postoperative complications were significantly more frequent in patients with elevated preoperative d-dimer levels compared with those with normal d-dimer levels (26 vs. 10 %; p = 0.032). The prevalence of postoperative complications showed a stepwise increase in proportion to the coagulation score. Patients with a coagulation score of 2 had significantly larger tumors (p = 0.013) and significantly greater intraoperative blood loss (p = 0.004) than those who scored 0 or 1. Coagulation score showed the highest values distinguished high-risk patients in overall and disease-free survival, and a coagulation score of 2 was an independent prognostic factor for recurrence. Patients with a coagulation score of 2 experienced a significantly higher prevalence of liver metastasis as an initial recurrence than those who scored 0 or 1 (p = 0.019).

CONCLUSIONS

The coagulation score is a simple and promising predictor for postoperative complications and recurrence after gastrectomy in stage II/III GC patients.

Combination of preoperative platelet/lymphocyte and neutrophil/lymphocyte rates and tumor-related factors to predict lymph node metastasis in patients with gastric cancer

OBJECTIVE

Lymph node (LN) metastasis is widely accepted as a poor prognosis indicator in patients with gastric cancer. An accurate preoperative prediction of LN status is of crucial importance for the planning treatment. The aim of the present study was to assess the predictive value of the preoperative platelet/lymphocyte (PLR) and neutrophil/lymphocyte rates (NLR) on the LN metastasis in gastric cancer patients and to develop a new preoperative score system to predict LN metastasis.

PATIENTS AND METHODS

A total of 492 operable patients with gastric cancer were enrolled in our study. The clinical utility of the PLR and NLR was evaluated by receiver operating characteristic (ROC) curves. The logistic analysis was used to identify the independent parameters associated with LN metastasis. Then, a score system including those independent parameters that can be detected preoperatively was established, which was also tested by an ROC curve.

RESULTS

The ideal cutoff values for predicting LN metastasis were 1.59 for NLR and 155.67 for PLR according to the ROC curve. Multivariate analyses showed that both PLR and NLR are significantly associated with LN metastasis independent of depth of invasion, lymphatic invasion, macroscopic type, and tumor size. The area under the ROC curve of the score system was 0.830 (95% confidence interval 0.782-0.878), showing a reliable ability to evaluate the status of nodal involvement.

CONCLUSION

Preoperative PLR and NLR are useful biomarkers to predict LN metastasis and the score system in our study may serve as a reliable instrument to predict LN metastasis in gastric cancer patients.

Gastric Adenocarcinomas Express the Glycosphingolipid Gb3/CD77: Targeting of Gastric Cancer Cells with Shiga Toxin B-Subunit

The B-subunit of the bacterial Shiga toxin (STxB), which is nontoxic and has low immunogenicity, can be used for tumor targeting of breast, colon, and pancreatic cancer. Here, we tested whether human gastric cancers, which are among the most aggressive tumor entities, express the cellular receptor of Shiga toxin, the glycosphingolipid globotriaosylceramide (Gb3/CD77). The majority of cases showed an extensive staining for Gb3 (36/50 cases, 72%), as evidenced on tissue sections of surgically resected specimen. Gb3 expression was detected independent of type (diffuse/intestinal), and was negatively correlated to increasing tumor-node-metastasis stages (P = 0.0385), as well as with markers for senescence. Gb3 expression in nondiseased gastric mucosa was restricted to chief and parietal cells at the bottom of the gastric glands, and was not elevated in endoscopic samples of gastritis (n = 10). Gb3 expression in established cell lines of gastric carcinoma was heterogeneous, with 6 of 10 lines being positive, evidenced by flow cytometry. STxB was taken up rapidly by live Gb3-positive gastric cancer cells, following the intracellular retrograde transport route, avoiding lysosomes and rapidly reaching the Golgi apparatus and the endoplasmic reticulum. Treatment of the Gb3-expressing gastric carcinoma cell line St3051 with STxB coupled to SN38, the active metabolite of the topoisomerase type I inhibitor irinotecan, resulted in >100-fold increased cytotoxicity, as compared with irinotecan alone. No cytotoxicity was observed on gastric cancer cell lines lacking Gb3 expression, demonstrating receptor specificity of the STxB-SN38 compound. Thus, STxB is a highly specific transport vehicle for cytotoxic agents in gastric carcinoma. Mol Cancer Ther; 15(5); 1008-17. ©2016 AACR.

Trends in the use and impact of neoadjuvant chemotherapy on perioperative outcomes for resected gastric cancer: Evidence from the American College of Surgeons National Cancer Database

BACKGROUND

Standard of care for patients with advanced gastric cancer includes administration of neoadjuvant chemotherapy (NAC) before resection. This study assesses the pattern of use and impact of NAC on perioperative outcomes in US medical centers.

METHODS

Using the American College of Surgeons National Cancer Database, 16,128 patients underwent gastrectomy for cancer from 2003 to 2012. Treatment groups were categorized as NAC or no NAC (ie, adjuvant chemotherapy and surgery only). Univariate and multivariate analyses were performed to estimate trends in utilization and impact of treatment on perioperative outcomes.

RESULTS

Of patients undergoing gastrectomy, 36.6% received NAC and 63.4% did not receive chemotherapy in the neoadjuvant setting. Patients who received NAC were more frequently younger, male, white, privately insured, with fewer comorbidities, and treated at an academic center (all P < .0001). After controlling for demographics, comorbidities, and tumor-related factors, patients who received NAC had a postoperative duration of stay 0.43 days shorter than patients who did not receive chemotherapy (5.79 vs 6.22 days; P = .050). They had a 36% lower odds of 30-day mortality (odds ratio, 0.64, P < .0001) but nonsignificant lower odds of 90-day mortality. Use of NAC increased annually, with the greatest increases seen in academic facilities and in the Northeast and North Central United States.

CONCLUSION

With concerns regarding the toxicity of NAC, these findings suggest that NAC is not associated with worse postoperative outcomes. In light of evidence touting the benefits of NAC, its adoption as a component in the multimodality care of gastric cancer is slowly increasing, although use of NAC remains poor overall.

Postoperative adjuvant treatment for gastric cancer improves long-term survival after curative resection and D2 lymphadenectomy. Results from a Latin American Center

BACKGROUND

The benefits of adjuvant treatment in the context of a D2 lymph node dissection are controversial. The aim was to investigate the effects of postoperative adjuvant treatment on the survival of patients with a curative resection for gastric cancer and a D2 lymph node dissection.

METHODS

We performed a retrospective cohort study. Patients operated from 1996 to 2013 were selected. We compared long term survival of patients treated with surgery alone and those with surgery plus postoperative adjuvant treatment. A multivariate analysis for survival was applied in every stage.

RESULTS

The study included 580 patients. Two-hundred and four patients received postoperative adjuvant treatment (AD) and 376 patients were treated only with surgery (SU). Patients in the AD group were younger (60 versus 68, p < 0.001), had a lower rate of multiple organ resection (21% versus 39%, p < 0.001) and had less postoperative complications (14% versus 32%, p < 0.001). In the AD group, patients had more advanced disease (stage III; 77% versus 66%, p < 0.001). No difference was found in lymph nodes resected (31 versus 30, p = ns). The median survival with adjuvant treatment was 33 months (39% 5 year survival) and 22 months (31% 5 year survival) for patients without adjuvant treatment (p = 0.003). On multivariate analysis, patients with stage IIIB and IIIC had significantly better overall and disease specific long-term survival with adjuvant treatment.

CONCLUSIONS

These results suggest that there is a long-term survival benefit for patients treated with postoperative adjuvant treatment for stages IIIB and IIIC gastric cancer after D2 lymph node dissection.

Long non-coding RNA MEG3 functions as a competing endogenous RNA to regulate gastric cancer progression

Background

Long noncoding RNAs (lncRNAs) have recently emerged as important regulators in governing fundamental biological processes, and many of which are likely to have functional roles in tumorigenesis. Maternally expressed gene 3 (MEG3) gene encodes a lncRNA whose expression is lost in an expanding list of primary human tumors and tumor cell lines, however its biological role and regulatory mechanism in gastric cancer (GC) development and progression are poorly defined.

Methods

Quantitative RT-PCR analysis was used to determine whether aberrant MEG3 expression was associated with GC patients pTNM stage and pM state. Furthermore, the effect of ectopic expression of MEG3 on cell proliferation, migration, invasion and cell apoptosis was assessed by using CCK-8, wound healing, transwell invasion assays and flow cytometric analysis, respectively, in GC cell lines HGC-27 and MGC-803. Moreover, the competing endogenous RNA (ceRNA) activity of MEG3 on miR-181a was investigated via luciferase reporter assay and immunoblot analysis.

Results

MEG3 is decreased in GC patients and cell lines, and its expression was associated with metastatic GC. Furthermore, ectopic expression of MEG3 in HGC-27 and MGC-803 cells inhibited cell proliferation, migration, invasion, and promoted cell apoptosis, which might be due to MEG3 sequestering oncogenic miR-181 s in GC cells. Furthermore, MEG3 could up-regulated Bcl-2 via its competing endogenous RNA (ceRNA) activity on miR-181a.

Conclusions

These findings suggest that lncRNA MEG3, a ceRNA of miR-181 s, could regulate gastric carcinogenesis and may serve as a potential target for antineoplastic therapies.

Long non-coding RNA MEG3 functions as a competing endogenous RNA to regulate gastric cancer progression

BACKGROUND

Long noncoding RNAs (lncRNAs) have recently emerged as important regulators in governing fundamental biological processes, and many of which are likely to have functional roles in tumorigenesis. Maternally expressed gene 3 (MEG3) gene encodes a lncRNA whose expression is lost in an expanding list of primary human tumors and tumor cell lines, however its biological role and regulatory mechanism in gastric cancer (GC) development and progression are poorly defined.

METHODS

Quantitative RT-PCR analysis was used to determine whether aberrant MEG3 expression was associated with GC patients pTNM stage and pM state. Furthermore, the effect of ectopic expression of MEG3 on cell proliferation, migration, invasion and cell apoptosis was assessed by using CCK-8, wound healing, transwell invasion assays and flow cytometric analysis, respectively, in GC cell lines HGC-27 and MGC-803. Moreover, the competing endogenous RNA (ceRNA) activity of MEG3 on miR-181a was investigated via luciferase reporter assay and immunoblot analysis.

RESULTS

MEG3 is decreased in GC patients and cell lines, and its expression was associated with metastatic GC. Furthermore, ectopic expression of MEG3 in HGC-27 and MGC-803 cells inhibited cell proliferation, migration, invasion, and promoted cell apoptosis, which might be due to MEG3 sequestering oncogenic miR-181 s in GC cells. Furthermore, MEG3 could up-regulated Bcl-2 via its competing endogenous RNA (ceRNA) activity on miR-181a.

CONCLUSIONS

These findings suggest that lncRNA MEG3, a ceRNA of miR-181 s, could regulate gastric carcinogenesis and may serve as a potential target for antineoplastic therapies.

Delta-Shaped Gastroduodenostomy in Fully Laparoscopic Distal Gastrectomy: A Retrospective Study

This study aims to explore the technical feasibility, safety, and clinical efficacy of delta-shaped anastomosis for digestive tract reconstruction during totally laparoscopic distal gastrectomy. Clinical data of 24 patients who received totally laparoscopic distal gastrectomy with delta-shaped anastomosis (laparoscopic gastrectomy group, LG group) and 30 patients who received open distal gastrectomy for gastric cancer (open gastrectomy group, OG group) from April 2013 to April 2014 were retrospectively analyzed. Operation time, intraoperative blood loss, postoperative time to intestinal function recovery, postoperative pain, postoperative hospital stay, and incidence of postoperative complications (infection, obstruction, and delayed gastric emptying) were compared between these 2 groups. Patients in both groups were discharged without marked complications. No patients who initially selected laparoscopy were converted to laparotomy. Patients in the LG group had longer operation times (175.3 ± 64.7  minutes versus 120.1 ± 43.4  minutes, P < 0.05), lower intraoperative blood loss (50.8 ± 25.3  mL versus 95.6 ± 20.7  mL, P < 0.05), faster recovery of intestinal function (1.2 ± 0.5 days versus 2.6 ± 1.0 days, P < 0.05), less postoperative pain (5.6 ± 0.7 versus 9.5 ± 0.3, P < 0.05), and shorter length of postoperative hospital stay (8.5 ± 2.2 days versus 12.2 ± 3.8 days, P < 0.05), compared with patients in the OG group. There were no significant differences with respect to surgical margins achieved, the number of lymph nodes retrieved or incidence of postoperative complications (infection, obstruction, and delayed gastric emptying) between the 2 groups (P > 0.05). Laparoscopic reconstruction of the digestive tract through delta-shaped anastomosis appears to be safe, feasible, and associated to rapid recovery. These data argue for more wide-spread implementation of this procedure.

15-PGDH expression as a predictive factor response to neoadjuvant chemotherapy in advanced gastric cancer

Given the various clinical and pathologic responses to neoadjuvant chemotherapy (NACT) in gastric cancer (GC), potential biomarkers that reflecting the efficacy of NACT on GC should be investigated. The aim of this study was to investigate the 15-PGDH expression response to NACT in GC patients and its relationship with prognosis of GC. Immunohistochemical method was used to assess the level of 15-PGDH expression in 56 GC patients who received NACT before surgery and 46 patients who underwent surgical treatment without NACT as well as their corresponding adjacent non-neoplastic tissues. We found that there was no correlation of 15-PGDH expression between non-cancerous gastric tissues and GC tissues (P=0.519), while 15-PGDH expression level in NACT group was higher than that in nNACT group (P=0.015). In patients with NACT, the higher level of 15-PGDH expression was significantly associated with well-moderately differentiated grade (P=0.023), I/II stage (P=0.014) and with no lymph node metastasis (P=0.016). Moreover, statistically significant differences in overall survival (OS) were found among 15-PGDH expression (log-rank test, P<0.001) and TNM stage (log-rank test, P=0.032). Most importantly, expression of 15-PGDH was found to be an independent predictive factor by multivariate analysis (Hazard ratio (HR) 0.315 [0.120-0.827], P=0.019). These findings indicated that NACT could increase 15-PGDH expression in advanced GC patients, and 15-PGDH may serve as a candidate prognostic biomarker of advanced GC response to NACT.