Chemotherapy for patients with gastric cancer after complete resection: A network meta-analysis

The order of surgery and chemotherapy matters: Multimodality therapy and stage-specific differences in survival in gastric cancer

BACKGROUND AND OBJECTIVES

Multimodality treatment improves survival for gastric cancer (GC). However, the effect of treatment sequence by stage remains unclear. We aim to compare outcomes between patients receiving neoadjuvant(neoadj) and adjuvant chemotherapy (adj).

METHODS

Nonmetastatic GC patients with clinical stage ≥ T2N0 who underwent both resection and neoadj or adj were identified using the National Cancer Database (2005-2014). Multivariable Cox regression analyses were performed on propensity score-matched (PSM) cohorts stratified by stage to compare overall survival (OS).

RESULTS

We identified 11 984 patients; 55% stage I (SI), 76% stage II (SII) and 57% stage III (SIII) received neoadj. Unadjusted analysis showed worse survival among SI neoadj patients (hazard ratio [HR] 1.195, confidence interval [CI] 1.04-1.38) and improved survival for SII (HR 0.93 CI 0.87-0.998) and SIII (HR 0.75, CI 0.68-0.84). After PSM, SI patients with neoadj had worse OS with increased risk of death compared to Adj (HR 1.186, CI 1.004-1.402). SII patients had no difference in OS (HR 0.98, CI 0.91-1.07) and SIII patients had improved OS (HR 0.78, CI 0.69-0.90).

CONCLUSIONS

In patients who received surgery and chemotherapy, the benefit of neoadj was limited to SIII with worse survival for SI. A clinical trial to examine the optimal sequence of chemotherapy is warranted.

Effects of Sophora flavescens aiton and the absorbed bioactive metabolite matrine individually and in combination with 5-fluorouracil on proliferation and apoptosis of gastric cancer cells in nude mice

Background: Sophora flavescens aiton (SFA) and its main bioactive metabolite matrine are widely used in traditional Chinese medicine (TCM) preparations and have achieved good curative effects for the treatment of various tumors. However, the mechanisms underlying SFA and matrine individually and in combination with chemotherapeutic drugs for treatment of gastric cancer (GC) remain unclear. Aim of the study: To elucidate the mechanisms underlying the ability of SFA and matrine individually and in combination with chemotherapeutic drugs to inhibit proliferation and promote apoptosis of human GC cells. Materials and methods: Forty-eight nude mice were randomly divided into six groups that were treated with normal saline (model group), 5-fluorouracil (5-FU), SFA decoction (SFAD), matrine, SFAD+5-FU, or matrine+5-FU. A subcutaneous heterotopic tumor model was established in nude mice by implantation of human GC BGC-823 cells. All mice were treated for 28 days. Bioactive metabolites in SFA were determined by HPLC-MS/MS. The tumor volume, tumor weight, and tumor inhibition rate of mice were documented. Histopathology and ultramicroscopic pathology of tumor tissues were observed. The tumor cell cycle and apoptosis in vivo were detected. Serum levels of PCNA, BAX, Bcl-2, Caspase-9, Caspase-3 and cleaved Caspase-3 were measured. Protein levels of MS4A10, MS4A8, MS4A7, PCNA, BAX, Bcl-2, Caspase-3, and cleaved Caspase-3 were measured in tumor tissues. Results: Both SFAD and matrine inhibited the growth of transplanted GC cells, which was more effective when combined with 5-FU. The tumor inhibition rates of the 5-FU, SFAD, matrine, SFAD+5-FU, and matrine+5-FU groups were 53.85%, 33.96%, 30.44%, 59.74%, and 56.55%, respectively. The body weight of tumor-bearing nude mice was greater in the SFAD group than the normal saline and matrine groups. SFAD+5-FU and matrine+5-FU blocked BGC-823 cells in the G0-G1/S transition, promoted apoptosis, and significantly decreased the content of serum apoptosis-inhibitory proteins (PCNA and Bcl-2) as well as protein expression of MS4A8, MS4A10, Bcl-2, and PCNA in tumor tissues, while increasing serum levels of pro-apoptotic proteins (Caspase-9, Caspase-3 and cleaved-Caspase-3) and protein expression of BAX and cleaved-Caspase-3 in tumor tissues. Conclusion: SFAD and matrine both individually and in combination with 5-FU ameliorated malignancy of transplanted tumors by reducing proliferation and promoting apoptosis of BGC-823 cells. These findings confirm the anti-tumor synergistic effect of TCM and chemotherapeutic drugs.

Identification of a chemotherapy-associated gene signature for a risk model of prognosis in gastric adenocarcinoma through bioinformatics analysis

BACKGROUND

Over the past few years, the overall survival rate of patients with gastric adenocarcinoma who have received different chemotherapy regimens has increased. However, not all gastric cancer patients who receive chemotherapy have a longer survival. We need better predictive biomarkers. This study is to construct a new risk model of chemotherapy-associated genes in gastric adenocarcinoma (GA) for prognostication.

METHODS

RNA-seq data and clinical information of GSE26901 (containing 44 chemotherapy samples and 65 patients without chemotherapy) in Gene Expression Omnibus (GEO) and stomach adenocarcinoma (STAD, containing 360 cancer tissue samples and 50 paired normal tissue samples) in The Cancer Genome Atlas (TCGA) were selected for screening differentially expressed genes (DEGs). Multivariate Cox regression was conducted to screen prognosis-associated genes and its link to patients' prognosis were screened by least absolute shrinkage and selection operator (LASSO) regression analysis. Based on the key genes, a risk scoring equation for the prognosis model was established, and constructed survival prognosis model. The model was tested for predictive ability through training set (TCGA datasets) and validation set (GSE84437). The correlations of the risk score with clinical pathological features, immune score and drug sensitivity score were evaluated.

RESULTS

In total, 179 overlapping genes were obtained by screening DEGs. Univariate Cox analysis revealed 36 prognosis-related genes, and LASSO regression analysis revealed 8 key genes (KCNJ2, GATA5, CLDN1, SERPINE1, FCER2, PMEPA1, TMEM37 and CRTAC1). Kaplan-Meier (K-M) analysis uncovered a relatively short overall survival time in the high-risk group. The model was verified to possess favourable predictive ability. In addition, the nomogram model were demonstrated good predictability with area under the curve (AUC) for 1-5 years in training set were 0.78, 0.78, 0.76, 0.79 and 0.81. The high-risk group was less likely to get benefits from immunotherapy and less sensitive to cisplatin.

CONCLUSIONS

According to the results of our training set and validation set, the risk model based on the eight chemotherapy-related gene signatures predicting prognosis has certain predictive accuracy in predicting the survival of GA patients which can be a promising prognostic parameter for GA. However, its efficacy remains to be proved in clinical practice.

lncRNA ROR Promotes Gastric Cancer Drug Resistance

OBJECTIVE

Gastric cancer is one of the most common malignant tumors worldwide, and for resectable tumors, the most effective treatment is surgery with chemotherapy in neoadjuvant or adjuvant setting. However, the majority of patients fail to achieve the ideal initial response and/or develop resistance to chemotherapy. It was reported that long noncoding RNA regulator of reprogramming (ROR) is highly associated with the progression of gastric cancer. However, the role ROR in multidrug resistance (MDR) remains unclear.

METHODS

The messenger RNA levels of 63 specimens of patients with gastric cancer were determined by real-time polymerase chain reaction analysis and were correlated with drug resistance and survival of patients. To determine the cellular functions of ROR, we generated gastric cancer MDR cells. The effect of ROR depletion on multidrug resistance-associated protein 1 (MRP1) expression and cell apoptosis were examined by immunoblotting analyses, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and flow cytometry.

RESULTS

We found that ROR expression levels are positively associated with increased MDR and poor prognosis of patients with gastric cancer. Regulator of reprogramming expression is increased in gastric cancer cells resistant to adriamycin (ADR) and vincristine (VCR). Depletion of ROR reduced MRP1 expression and increased apoptosis of drug-resistant gastric cancer cells in response to ADR and VCR treatment.

CONCLUSIONS

We demonstrated that ROR expression promotes MRP1 expression and MDR of gastric cancer cells and is correlated with increased MDR and poor prognosis of patients with gastric cancer. Our finding highlighted the potential of targeting ROR to improve the efficacy of chemotherapy.

Calponin 3 Regulates Cell Invasion and Doxorubicin Resistance in Gastric Cancer

Calponin 3 (CNN3) is an F-actin-binding protein that regulates actin cytoskeletal rearrangement. However, the role of CNN3 in cancer cell invasion and resistance to chemotherapeutic agents has not yet been investigated. The present study was undertaken to investigate whether CNN3 influences cancer-related phenotypes in gastric cancer. We demonstrate that CNN3 contributes to cell invasion and resistance to doxorubicin in gastric cancer. CNN3 expression was markedly elevated in highly invasive cancer cell lines compared to less invasive or noninvasive cancer cell lines. Depletion of CNN3 protein suppressed the invasive ability of gastric cancer cells. The highly invasive MKN-28 gastric cancer cells were more resistant to doxorubicin than the noninvasive MKN-45 cells; however, knockdown of CNN3 expression in MKN-28 cells resensitized them to doxorubicin treatment. Taken together, our results suggest that CNN3 plays a key role in invasiveness and doxorubicin resistance in gastric cancer cells.

MicroRNA-613 induces the sensitivity of gastric cancer cells to cisplatin through targeting SOX9 expression

Increasing evidences have suggested that deregulated miRNAs may involve in drug chemoresistance in a lot of human cancers. However, the role of miR-613 in drug chemoresistance of GC cell is still unknown. The expression of miR-613 and Sex-determining region Y (SRY)-box 9 (SOX9) in GC tissues and cell lines was detected by using qRT-PCR. Cell migration and viability were measured by the wound healing assay and CCK-8 assays. Western blot and dual-luciferase reporter were done to identify the target gene of miR-613. We showed that miR-613 expression was downregulated in GC tissues and cell lines. Ectopic expression of miR-613 increased the sensitivity of GC cells to cisplatin. Overexpression of miR-613 suppressed GC cell proliferation, cycle and migration. In addition, we identified SOX9 was a direct target gene of miR-613 in GC cell. We showed that SOX9 expression was upregulated in gastric cancer samples. Moreover, the expression of SOX9 was negatively correlated with miR-613 expression in GC tissues. Furthermore, elevated expression of miR-613 increased the sensitivity of GC cells to cisplatin and suppressed GC cell proliferation and migration by targeting SOX9. These data suggested that miR-613 might function as a chemoresistant suppressor in GC.

A systematic review and network meta-analysis protocol of adjuvant chemotherapy regimens for resected gastric cancer

BACKGROUND

Gastric cancer is the third leading cause of cancer death in the world. The benefit of adjuvant chemotherapy has been demonstrated by published individual patient data meta-analysis and Cochrane systematic review. However, there is no consensus on which is the optimal adjuvant chemotherapy regimens. Present network meta-analysis aims to compare the differences of effect between all available adjuvant chemotherapy regimens in improving overall survival and disease-free survival, and to rate the certainty of evidence from present network meta-analysis.

METHODS

We will conduct this systematic review and network meta-analysis using Bayesian method and according to Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) statement. We will search PubMed, EMBASE.com, the Cochrane Central Register of Controlled Trials (CENTRAL), Chinese National Knowledge Infrastructure (CNKI), and Chinese Biological Medical Database (CBM), and ClinicalTrials.gov (http://clinicaltrials.gov/) to identify randomized controlled trials (RCTs) comparing adjuvant chemotherapy to surgery alone. We will assess the risk of bias of individual RCTs using a modified version of Cochrane tool. We will also use the advance of GRADE to rate the certainty of network meta-analysis. Data analysis will be performed with R-3.4.1 and WinBUGS software.

RESULTS

The results of this study will be published in a peer-reviewed journal.

DISCUSSION

To the best of our knowledge, this systematic review and network meta-analysis will firstly use both direct and indirect evidence to compare the differences of all available adjuvant chemotherapy regimens for resected gastric cancer patients. This is a protocol of systematic review and meta-analysis, so the ethical approval and patient consent are not required.

Comparative effectiveness of preoperative, postoperative and perioperative treatments for resectable gastric cancer: A network meta-analysis of the literature from the past 20 years

BACKGROUND

Different preoperative, postoperative or perioperative treatment strategies, including chemotherapy or chemoradiotherapy, are available for patients with gastric cancer, but conventional meta-analyses that assess two alternative treatments are unable to compare differences in overall survival. Thus, we performed a network meta-analysis to identify the best treatment strategy.

METHODS

We systematically searched and assessed studies for eligibility and extracted data. We then pooled the data and conducted a Bayesian network meta-analysis to combine direct comparisons with indirect evidence. The node-splitting method was used to assess the inconsistency. Rank probabilities were assessed by the probability of treatment rankings.

RESULTS

Thirty-three eligible randomized controlled trials were included in the network meta-analysis. Four treatments that had significantly improved prognoses when compared with surgery only were postoperative chemotherapy [HR = 0.80 with 95% CrI: (0.73, 0.88)], postoperative chemoradiotherapy [HR = 0.73 with 95% CrI: (0.61, 0.87)], preoperative chemoradiotherapy [HR = 0.77 with 95% CrI: (0.62, 0.98)] and perioperative chemotherapy [HR = 0.69 with 95% CrI: (0.55, 0.84)]. Preoperative chemotherapy, however, did not significantly improve survival when compared with surgery alone [HR = 0.94 with 95% CrI: (0.71, 1.2)]. There was no statistically significant difference between postoperative chemotherapy, postoperative chemoradiotherapy, preoperative chemoradiotherapy and perioperative chemotherapy in terms of overall survival. Chemoradiotherapy after D2 lymphadenectomy did not significantly improve OS when compared with postoperative chemotherapy [HR = 0.95 with 95% CrI: (0.73, 1.3)].

CONCLUSION

Among patients with operable gastric cancer, perioperative chemotherapy had the highest probability of being the best treatment. Further clinical resources may be required to assess the efficacy and safety of perioperative chemotherapy for patients with gastric cancer.

A Novel Mechanism of Doxorubicin Resistance and Tumorigenesis Mediated by MicroRNA-501-5p-Suppressed BLID

Doxorubicin is a widely used anthracycline-based anti-tumor agent for both solid and liquid tumors. Mounting evidence has demonstrated that microRNAs (miRNAs) are involved in chemoresistance and tumorigenesis. However, the roles of microRNA-501-5p (miR-501) in doxorubicin resistance and gastric cancer cell proliferation and invasion are still not fully understood. In this study, we identified that BLID (BH3-like motif-containing protein, cell death inducer) was directly regulated by miR-501 at the post-transcriptional level in multiple gastric cancer cell lines. Endogenous miR-501 was higher, whereas BLID was lower, in doxorubicin-resistant gastric cancer SGC7901/ADR cells compared with their parental SGC7901 cells. miR-501 suppressed gastric cancer cell apoptosis, induced resistance to doxorubicin, and enhanced cell proliferation, migration, and invasion. Subcutaneous injection of miR-501 lentivirus-infected SGC7901 cells resulted in rapid growth of xenograft tumors and resistance to doxorubicin treatment, unlike injection of negative miRNA lentivirus-infected SGC7901 cells. This is achieved at least partially by directly targeting BLID and subsequent inactivation of caspase-9 and caspase-3 and phosphorylation of Akt. Taken together, miR-501 induces doxorubicin resistance and enhances the tumorigenesis of gastric cancer cells by suppressing BLID. miR-501 might be a potential target for doxorubicin resistance and gastric cancer therapy.

Transcription activated p73-modulated cyclin D1 expression leads to doxorubicin resistance in gastric cancer

Gastric cancer (GC) is one of the leading types of cancer in terms of mortality cases worldwide. Doxorubicin (Dox), a common chemotherapy drug, is frequently used to treat GC; however, acquired resistance to Dox hinders the chemotherapeutic outcome and causes shorter survival in GC patients. Several Dox-resistant GC cell lines, including SGC7901, SNU-1 and SNU-5 were generated to investigate the mechanism of Dox resistance in GC. Various methods were used to test the response of Dox-resistant GC cells and parental cells, including flow cytometry, Cell Counting kit-8 assay, reverse transcription polymerase chain reaction and western blot analysis. In the present study, various Dox-resistant cells presented reduced apoptosis and cell cycle arrest in response to Dox treatment. Western blot results revealed that cyclin D1 was upregulated in Dox-resistant cells, whereas inhibition or depletion of cyclin D1 re-sensitized the resistant cells to Dox treatment, which indicated that the induction of cyclin D1 expression was a result of the Dox resistance in GC cells. Furthermore, it was observed that a transcription activated form of p73 (TAp73), is the upstream modulator of cyclin D1, manipulating the cyclin D1 transcription with the assistance of activator protein 1 (AP-1). Overall, the present study data provided a rational strategy to overcome the Dox resistance in GC treatment by inhibiting cyclin D1 expression.

Resveratrol reverses Doxorubicin resistance by inhibiting epithelial-mesenchymal transition (EMT) through modulating PTEN/Akt signaling pathway in gastric cancer

BACKGROUND

Gastric cancer is one of the major causes of cancer-related mortality worldwide. Most of patients presenting with inoperable gastric cancers rely on systemic chemotherapy for prolongation of survival. Doxorubicin (DOX) is one of the important agents against gastric cancer. Acquired DOX-resistance severely impedes the chemotherapeutic effect, invariably leading to poor prognosis. Resveratrol (RES) as a kind of phytoalexin has demonstrated anti-tumor functions in breast cancer and myeloid leukemia, but its function and mechanism are still unknown in gastric cancer treatment.

METHODS

CCK8 assay was used to detect the cytotoxicity of DOX and RES to gastric cancer cells. DOX-resistant subclone cell line (SGC7901/DOX) was derived from SGC7901 cells exposed to stepwise increasing concentrations of DOX treatment. We measured the migratory capabilities of SGC7901/DOX cells by Cell scratch test and Transwell assay. SGC7901/DOX cells were treated with DOX, RES, neither or both. Then we analyzed cell survival by CCK8 assay, colony formation by Colony-forming assay, cell apoptosis by Annexin-V-FITC and PI dual staining assay and cell migration by Cell scratch test and Transwell assay. Western blotting was conducted to detect the protein expressions of PTEN/Akt signaling pathway and EMT-related markers. Immunofluorescence was performed to confirm the EMT-related markers expressions. The xenograft model was used to assess the effect of DOX and RES in vivo. The key molecules associated with proliferation, apoptosis and EMT were evaluated by immunohistochemistry in tumor specimens.

RESULTS

SGC7901/DOX cells acquired drug resistance and enhancive migratory capability. RES enabled SGC7901/DOX cells to regain DOX sensitivity, mitigated the aggressive biological features, promoted cell apoptosis in vitro and inhibited tumor growth in vivo. Mechanistic studies revealed that SGC7901/DOX cells underwent epithelial-mesenchymal transition (EMT) which was induced by Akt activation, and through activating PTEN, RES inhibited the Akt pathway, and then achieved the reversion of EMT.

CONCLUSION

RES serves as a novel solution to reverse the DOX-resistance of gastric cancer via preventing EMT by modulating PTEN/Akt signaling pathway. DOX-RES combined treatment provides a promising future for gastric cancer patients to postpone drug resistance and prolong survival.

Recent insights in the therapeutic management of patients with gastric cancer

Gastric cancer remains frequent and one of the most lethal malignancies worldwide. In this article, we aimed to comprehensively review recent insights in the therapeutic management of gastric cancer, with focus on the surgical and perioperative management of resectable forms, and the latest advances regarding advanced diseases. Surgical improvements comprise the use of laparoscopic surgery including staging laparoscopy, a better definition of nodal dissection, and the development of hyperthermic intraperitoneal chemotherapy. The best individualized perioperative management should be assessed before curative-intent surgery for all patients and can consists in perioperative chemotherapy, adjuvant chemo-radiation therapy or adjuvant chemotherapy alone. The optimal timing and sequence of chemotherapy and radiation therapy with respect to surgery should be further explored. Patients with advanced gastric cancer have a poor prognosis. Nevertheless, they can benefit from doublet or triplet chemotherapy combination, including trastuzumab in HER2-positive patients. Upon progression, second-line therapy can be considered in patients with good performance status. Although anti-HER2 (trastuzumab) and anti-VEGFR (ramucirumab) may yield survival benefit, anti-EGFR and anti-HGFR therapies have failed to improve outcomes. Nevertheless, combination regimens containing cytotoxic drugs and targeted therapies should be further evaluated; keeping in mind that gastric cancer biology is different between Asia and the Western countries.

Current adjuvant treatment modalities for gastric cancer: From history to the future

The discrepancy between the surgical technique and the type of adjuvant chemotherapy used in clinical trials and patient outcomes in terms of overall survival rates has led to the generation of different adjuvant treatment protocols in distinct parts of the world. The adjuvant treatment recommendation is generally chemoradiotherapy in the United States, perioperative chemotherapy in the United Kingdom and parts of Europe, and chemotherapy in Asia. These options mainly rely on the United States Intergroup-0116, United Kingdom British Medical Research Council Adjuvant Gastric Infusional Chemotherapy, and the Asian Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer and Capecitabine and Oxaliplatin Adjuvant Study in Stomach Cancer trials. However, the benefits were evident for only certain patients, which were not very homogeneous regarding the type of surgery, chemotherapy regimens, and stage of disease. Whether the dissimilarities in survival are attributable to surgical technique or intrinsic biological differences is a subject of debate. Regardless of the extent of surgery, multimodal therapy may offer modest survival advantage at least for diseases with lymph node involvement. Moreover, in the era of individualized treatment for most of the other cancer types, identification of special subgroups comprising those who will derive more or no benefit from adjuvant therapy merits further investigation. The aim of this review is to reveal the historical evolution and future reflections of adjuvant treatment modalities for resected gastric cancer patients.

Multidrug Resistance-associated Protein-1 (MRP-1)-dependent Glutathione Disulfide (GSSG) Efflux as a Critical Survival Factor for Oxidant-enriched Tumorigenic Endothelial Cells

Endothelial cell tumors are the most common soft tissue tumors in infants. Tumor-forming endothelial (EOMA) cells are able to escape cell death fate despite excessive nuclear oxidant burden. Our previous work recognized perinuclear Nox-4 as a key contributor to EOMA growth. The objective of this work was to characterize the mechanisms by which EOMA cells evade oxidant toxicity and thrive. In EOMA cells, compared with in the cytosol, the nuclear GSSG/GSH ratio was 5-fold higher. Compared to the ratio observed in healthy murine aortic endothelial (MAE) cells, GSSG/GSH was over twice as high in EOMA cells. Multidrug resistance-associated protein-1 (MRP-1), an active GSSG efflux mechanism, showed 2-fold increased activity in EOMA compared with MAE cells. Hyperactive YB-1 and Ape/Ref-1 were responsible for high MRP-1 expression in EOMA. Proximity ligand assay demonstrated MRP-1 and YB-1 binding. Such binding enabled the nuclear targeting of MRP-1 in EOMA in a leptomycin-B-sensitive manner. MRP-1 inhibition as well as knockdown trapped nuclear GSSG, causing cell death of EOMA. Disulfide loading of cells by inhibition of GSSG reductase (bischoloronitrosourea) or thioredoxin reductase (auranofin) was effective in causing EOMA death as well. In sum, EOMA cells survive a heavy oxidant burden by rapid efflux of GSSG, which is lethal if trapped within the cell. A hyperactive MRP-1 system for GSSG efflux acts as a critical survival factor for these cells, making it a potential target for EOMA therapeutics.

Effect of Metabolic Inhibitors on the Hepatic Disposition of 5-Fluorouracil after Application to the Rat Liver Surface

We evaluated the effects of 5-fluorouracil (5-FU) metabolic inhibitors, gimeracil or uridine, on the hepatic disposition of 5-FU after application to the liver surface in rats, aiming to enhance the availability of 5-FU in the liver. 5-FU solution with or without metabolic inhibitors was applied to the rat liver surface using a cylindrical diffusion cell. The liver, blood and the remaining solution in the diffusion cell were collected at specified times, and assayed for 5-FU content. 5-FU absorption properties were not altered by addition of gimeracil and uridine. The 5-FU concentration in the diffusion cell attachment site of the rat liver (site 1) at 0.1-0.4 M ratios of gimeracil to 5-FU was significantly higher than that of the control. On the contrary, the addition of uridine did not increase the 5-FU concentration at site 1. At a 0.1 M ratio of gimeracil to 5-FU, the maximum 5-FU plasma concentration was the lowest, and the area under the 5-FU concentration-time curve at site 1 was 3.4 times greater than that of the control. We demonstrated that applying 5-FU with gimeracil to the rat liver surface could increase the availability of 5-FU in the liver.

A clinical prognostic scoring system for resectable gastric cancer to predict survival and benefit from paclitaxel- or oxaliplatin-based adjuvant chemotherapy

Background

Gastrectomy with D2 lymphadenectomy is a standard procedure of curative resection for gastric cancer (GC). The aim of this study was to develop a simple and reliable prognostic scoring system for GC treated with D2 gastrectomy combined with adjuvant chemotherapy.

Methods

A prognostic scoring system was established based on clinical and laboratory data from 579 patients with localized GC without distant metastasis treated with D2 gastrectomy and adjuvant chemotherapy.

Results

From the multivariate model for overall survival (OS), five factors were selected for the scoring system: ≥50% metastatic lymph node rate, positive lymphovascular invasion, pathologic TNM Stage II or III, ≥5 ng/mL preoperative carcinoembryonic antigen level, and <110 g/L preoperative hemoglobin. Two models were derived using different methods. Model A identified low- and high-risk patients for OS (P<0.001), while Model B differentiated low-, intermediate-, and high-risk patients for OS (P<0.001). Stage III patients in the low-risk group had higher survival probabilities than Stage II patients. Both Model A (area under the curve [AUC]: 0.74, 95% confidence interval [CI]: 0.69–0.78) and Model B (AUC: 0.79, 95% CI: 0.72–0.83) were better predictors compared with the pathologic TNM classification (AUC: 0.62, 95% CI: 0.59–0.71, P<0.001). Adjuvant paclitaxel- or oxaliplatin-based or triple chemotherapy showed significantly better outcomes in patients classified as high risk, but not in those with low and intermediate risk.

Conclusion

A clinical three-tier prognostic risk scoring system was established to predict OS of GC treated with D2 gastrectomy and adjuvant chemotherapy. The potential advantage of this scoring system is that it can identify high-risk patients in Stage II or III who may benefit from paclitaxel- or oxaliplatin-based regimens. Prospective studies are needed to confirm these results before they are applied clinically.

Multimodal treatment of gastric cancer in the west: Where are we going?

The incidence of gastric cancer (GC) is decreasing worldwide, especially for intestinal histotype of the distal third of the stomach. On the contrary, proximal location and diffuse Lauren histotype have been reported to be generally stable over time. In the west, no clear improvement in long-term results was observed in clinical and population-based studies. Results of treatment in these neoplasms are strictly dependent on tumor stage. Adequate surgery and extended lymphadenectomy are associated with good long-term outcome in early-stage cancer; however, results are still unsatisfactory for advanced stages (III and IV), for which additional treatments could provide a survival benefit. This implies a tailored approach to GC. The aim of this review was to summarize the main multimodal treatment options in advanced resectable GC. Perioperative or postoperative treatments, including chemotherapy, chemoradiotherapy, targeted therapies, and hyperthermic intraperitoneal chemotherapy have been reviewed, and the main ongoing and completed trials have been analyzed. An original tailored multimodal approach to non-cardia GC has been also proposed.

Polyunsaturated fatty acids augment tumoricidal action of 5-fluorouracil on gastric cancer cells by their action on vascular endothelial growth factor, tumor necrosis factor-α and lipid metabolism related factors

INTRODUCTION

Gastric cancer is the second most common cause of cancer-related mortality worldwide. 5-fluorouracil (5-FU) is a commonly used anti-cancer drug. Various polyunsaturated fatty acids (PUFAs) are known to have tumoricidal action both in vitro and in vivo. Though PUFAs are known to augment the cytotoxic action of anti-cancer drugs, the exact mechanism is not clear.

MATERIAL AND METHODS

The human gastric cancer cell line MGC (undifferentiated) and human gastric cancer cell line SGC (semi-differentiated) were either 5-FU alone or a combination of 5-FU + PUFAs and their proliferation, and ability to secrete tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) and lipid metabolism-related factors lipoprotein lipase (LPL), peroxisome proliferator-activated-γ (PPAR-γ), and CCAAT enhancer-binding protein (C/EBP) were investigated and analyzed.

RESULTS

It was noted that combined treatment of 5-FU + PUFAs on gastric carcinoma (MGC and SGC) cells produced a significant growth inhibitory action compared with either agent alone by inhibiting the production of TNF-α and VEGF and a simultaneous increase in the expression of LPL, PPAR-γ, and C/EBP.

CONCLUSIONS

Based on the results of the present study, it is concluded that PUFAs enhance the tumoricidal action of the anti-cancer drug 5-FU by acting on anti-angiogenic factors and enzymes involved in lipid metabolism.

Submucosal injection solution for endoscopic resection in gastrointestinal tract: a traditional and network meta-analysis

Objective. To explore and define the current optimal submucosal injection solution used in ESD and EMR for gastrointestinal tract neoplasms in terms of clinical outcomes and other aspects. Methods. PubMed, Cochrane Library, Embase, and clinical trials register center were searched with terms of “endoscopic resection” and “submucosal injection solution” to identify relevant randomized controlled trials (RCTs). Both direct comparison using traditional meta-analysis method and indirect comparison using network meta-analysis method were performed. Results. A total of 11 RCTs with 1152 patients were included. Meta-analysis showed that, compared with normal saline, other submucosal injection solutions induced a significant increase in terms of en bloc resection rate (I² = 0%, OR = 2.11, 95% CI (1.36, 3.26), and P = 0.008) and complete resection rate (I² = 0%, OR = 2.14, 95% CI (1.41, 3.24), and P = 0.0003); and there was no significant difference in the incidence of total complications (I² = 0%, OR = 0.87, 95% CI (0.59, 1.29), and P = 0.49). Conclusions. Other newly developed submucosal injection solutions significantly increased en bloc resection rate and complete resection rate and decreased bleeding rate and finical cost of endoscopic resection in gastrointestinal tract, while current evidence did not find the difference between them, which need to be explored by further studies.

Baicalein reverses hypoxia-induced 5-FU resistance in gastric cancer AGS cells through suppression of glycolysis and the PTEN/Akt/HIF-1α signaling pathway

Cancer cells can survive under hypoxia by metabolic reprogramming to achieve a high level of glycolysis, which contributes to the development of chemoresistance. Therefore, inhibition of glycolysis would be a novel strategy for overcoming hypoxia‑induced drug resistance. Baicalein, a flavonoid derived from the root of Scutellaria baicalensis, has been reported to exert strong antitumor activity toward various types of cancer. In the present study, we evaluated the effect of baicalein on hypoxia-induced 5-fluorouracil (5-FU) resistance in gastric cancer AGS cells and investigated the possible molecular mechanisms. We found that baicalein increased the sensitivity of AGS cells to 5-FU treatment under hypoxia. In addition, the hypoxia-enhanced glycolytic flux and expression of several critical glycolysis-associated enzymes (HK2, LDH-A and PDK1) in the AGS cells were suppressed by baicalein. Furthermore, baicalein inhibited hypoxia-induced Akt phosphorylation by promoting PTEN accumulation, thereby attenuating hypoxia-inducible factor-1α (HIF-1α) expression in AGS cells. These results together suggest that inhibition of glycolysis via regulation of the PTEN/Akt/HIF-1α signaling pathway may be one of the mechanisms whereby baicalein reverses 5-FU resistance in cancer cells under hypoxia.