Current status of adjuvant chemotherapy for gastric cancer

Updated Adjuvant Chemotherapy for Gastric Cancer

Surgical resection is currently the best curative approach for gastric cancer (GC); however, the prognosis of patients with advanced GC remains poor even with curative resection. For this reason, perioperative chemotherapy has been combined with surgery to reduce the risk of postoperative recurrence. Standard perioperative chemotherapy for resectable advanced GC varies from region to region. Postoperative S-1 therapy was standardized via the ACTS-GC study in East Asia, perioperative ECF (Epirubicin + Cisplatin + Fluorouracil) was standardized via the MAGIC study in Europe, and postoperative chemoradiotherapy was standardized via the US intergroup study in North America. Since then, more intensive regimens have been developed. In recent years, perioperative therapy using novel agents, such as molecular-targeted drugs and immune checkpoint inhibitors (ICIs), has also been tested and evaluated in the three major regions (East Asia, Europe, and North America) with promising results. Perioperative chemotherapy has become an integral part of many treatment strategies and requires continued research and evaluation.

Omentectomy vs omentum preservation for advanced gastric cancer: A systematic review and meta-analysis

Currently, gastric cancer is the sixth most prevalent cancer in the world. The recommended treatment for advanced disease is gastrectomy with D2 lymphadenectomy. However, there is no consensus regarding the performance of an omentectomy as part of the treatment. The procedure is considered by some authors to be essential for the elimination of a micrometastasis since cells in the peritoneum prefer growing in milky spots in the omentum. On the other hand, retrospective studies demonstrated that there is the possibility that omentum preservation may not impact patients' overall survival. Therefore, the objective of this review was to quantify the effect of performing an omentectomy to determine whether it is necessary. Medline (PubMed), Embase, Cochrane, ClinicalTrials.gov and LILACS were searched up to September 2022. Selection was restricted to comparative studies in patients with advanced GC (≥T2). The certainty of evidence was assessed with GRADEPro and the risk of bias with ROBINS-I and RoB 2.0. Five cohort studies, and one randomized controlled trial (RCT) were included. The meta-analysis found that there were no significant differences between the procedures for overall survival, relapse-free survival, and peritoneal recurrence. Furthermore, in perioperative outcomes, a significant difference was only found in intraoperative bleeding, which was lower in patients who had their omentum preserved. Therefore, omentum preservation in patients with advanced gastric cancer has been shown to have no inferior results than resection in long-term outcomes.

Creation of EGD-Derived Gastric Cancer Organoids to Predict Treatment Responses

Gastric adenocarcinoma (GAd) is the third leading cause of cancer-related deaths worldwide. Most patients require perioperative chemotherapy, yet methods to accurately predict responses to therapy are lacking. Thus, patients may be unnecessarily exposed to considerable toxicities. Here, we present a novel methodology using patient-derived organoids (PDOs) that rapidly and accurately predicts the chemotherapy efficacy for GAd patients. Methods:Endoscopic GAd biopsies were obtained from 19 patients, shipped overnight, and PDOs were developed within 24 h. Drug sensitivity testing was performed on PDO single-cells with current standard-of-care systemic GAd regimens and cell viability was measured. Whole exome sequencing was used to confirm the consistency of tumor-related gene mutations and copy number alterations between primary tumors, PDOs, and PDO single-cells. Results:Overall, 15 of 19 biopsies (79%) were appropriate for PDO creation and single-cell expansion within 24 h of specimen collection and overnight shipment. With our PDO single-cell technique, PDOs (53%) were successfully developed. Subsequently, two PDO lines were subjected to drug sensitivity testing within 12 days from initial biopsy procurement. Drug sensitivity assays revealed unique treatment response profiles for combination drug regimens in both of the two unique PDOs, which corresponded with the clinical response. Conclusions:The successful creation of PDOs within 24 h of endoscopic biopsy and rapid drug testing within 2 weeks demonstrate the feasibility of our novel approach for future applications in clinical decision making. This proof of concept sets the foundation for future clinical trials using PDOs to predict clinical responses to GAd therapies.

The roles and molecular mechanisms of long non-coding RNA WT1-AS in the maintenance and development of gastric cancer stem cells

It has been proposed that cancer stem cells (CSCs) are responsible for almost all malignant phenotypes of tumors. Long non-coding RNA WT1 antisense RNA (WT1-AS) has been found to be implicated in lung cancer cell stemness. However, the roles and molecular mechanisms of WT1-AS in the development of gastric cancer stem cells (GCSCs) remain unknown. Our present study showed that WT1-AS negatively regulated WT1 expression in GCSCs. WT1-AS knockdown or Wilms' tumor 1 (WT1) overexpression improved GCSC proliferative and migratory capacities, inhibited GCSC apoptosis, potentiated the resistance of GCSCs to 5-FU, promoted GCSC EMT, induced HUVEC angiogenesis, enhanced GCSC stemness, and facilitated in-vitro 3D GCSC aggregate formation. WT1-AS overexpression exerted reverse effects. WT1-AS ameliorated the malignant phenotypes of GCSCs by down-regulating WT1 in vitro. WT1-AS inhibited tumor growth and metastasis, and reduced tumor stemness in GCSCs-derived (s.c., i.p., and i.v.) xenografts in vivo. Moreover, XBP1 was identified as an upstream regulator of WT1-AS in GCSCs. Also, 4 potential WT1-AS downstream targets (i.e. PSPH, GSTO2, FYN, and PHGDH) in GCSCs were identified. Additionally, CACNA2D1 was demonstrated to be a downstream target of the WT1-AS/WT axis. XBP1 or CACNA2D1 knockdown exerted an adverse effect on the maintenance of stem cell-like behaviors and characteristics of GCSCs. In conclusion, WT1-AS weakened the stem cell-like behaviors and characteristics of GCSCs in vitro and in vivo by down-regulating WT1. Investigations into the molecular mechanisms underlying the complex phenotypes of GCSCs might contribute to the better management of gastric cancer.

Efficacy of S-1 or Capecitabine plus Oxaliplatin Adjuvant Chemotherapy for Stage II or III Gastric Cancer after Curative Gastrectomy: A Systematic Review and Meta-Analysis

Simple Summary

Adjuvant chemotherapy regimens tegafur/gimeracil/oteracil (S-1) and capecitabine plus oxaliplatin (CAPOX) have predominated, owing to evidence of their remarkable oncologic outcomes, however, there has been a lack of studies on the difference in efficacy between the two regimens. We conducted pairwise meta-analyses comparing the efficacy of S-1 and CAPOX regimens for overall survival (OS) and disease-free survival (DFS) in stage II or III gastric cancer patients. In all stages (stages II and III), the five-year OS was not different between the two regimens (hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.78–1.17; p = 0.56). Additionally, the five-year DFS was not different at any stage (HR 1.00, 95% CI 0.85–1.18; p = 0.21). The present meta-analysis showed that five-year OS and DFS for stage II or III gastric cancer patients were comparable between the S-1 and CAPOX adjuvant chemotherapy regimens.

Abstract

Background: Adjuvant chemotherapy (AC) regimens tegafur/gimeracil/oteracil (S-1) and capecitabine plus oxaliplatin (CAPOX) have predominated, however, there has been a lack of studies on their differences in efficacy. Methods: We conducted pairwise meta-analyses comparing the efficacy of S-1 and CAPOX regimens for overall survival (OS) and disease-free survival (DFS) in stage II or III GC patients. Results: Three studies were enrolled and analyzed using a forest plot for meta-analysis. Two of them were propensity score matching studies, and the remaining one was a retrospective observational study. In all stages, the five-year OS was not different between the two regimens (HR 0.96, 95% CI 0.78–1.17; p = 0.56). Additionally, the 5-year DFS was not different at any stage (HR 1.00, 95% CI 0.85–1.18; p = 0.21). After omitting the retrospective observational study, the five-year OS (HR 1.40, 95% CI 0.53–3.73) and DFS (HR 1.41, 95% CI 0.57–3.44) of S-1 tended to be better in stage II, and the five-year OS (HR 0.81, 95% CI 0.56–1.16) and DFS (HR 0.85, 95% CI 0.63–1.13) of CAPOX tended to be better in stage III, without statistical significance. Conclusions: In the present meta-analysis, the five-year OS and DFS for stage II or III GC patients were comparable between S-1 and CAPOX regimens as AC.

Protein-bound polysaccharide K prolonged overall survival in gastric cancer patients from a non-Japanese Asian country who received gastrectomy and adjuvant chemotherapy

Adding protein-bound polysaccharide K (PSK) to adjuvant chemotherapy with mitomycin and fluorouracil after gastrectomy for gastric cancer was demonstrated to improve survival in a previous study in Japan. However, the efficacy of PSK outside Japan and in combination with other adjuvant chemotherapeutic agents remains unclear. The aims of this study were to evaluate the efficacy of PSK. We conducted a population-based historical cohort study using the National Health Insurance Research Database of Taiwan. We performed sensitivity analysis with propensity score matching to control for possible confounders. Patients who used PSK (PSK group) were matched at a 1:4 ratio to those who had never used PSK (control group) after adjusting for covariates including sex, age, urbanization, income and comorbidities. The primary outcome was overall survival. Multivariate hazard ratios from competing risk analysis were calculated by adjusting for demographic data and all confounding factors. From 1999 to 2008, we identified 10,617 patients with gastric cancer received gastrectomy and adjuvant chemotherapy. 1295 patients used PSK (PSK group) and 5180 patients never used PSK (control group) were analyzed after propensity score matching. The median overall survival was 6.49 years (95% confidence interval [CI] 5.22-7.63) in the PSK group and 3.59 years (95% CI 3.38-3.80) in the control group. After adjusting for age, sex, urbanization, income, and comorbidities, adding PSK to adjuvant chemotherapy was the most significant prognostic factor for improved survival (hazard ratio 0.76, P < .0001). Adjuvant chemotherapy combined with PSK significantly prolonged overall survival in gastric cancer patients after gastrectomy.

Comparison of Long-Term Efficacy in S-1 and Capecitabine With Oxaliplatin as Adjuvant Chemotherapy for Patients With Gastric Cancer After Curative Surgery: A Retrospective, Single-Center Observational Study

Purpose: Various adjuvant chemotherapies have been introduced for gastric cancer patients after gastrectomy with D2 lymph node dissection. Although the mainstream regimen of adjuvant chemotherapy in Korea includes S-1 monotherapy (TS-1) and capecitabine with oxaliplatin (XELOX), few studies have compared the long-term efficacies of these 2 regimens. Methods: Between January 2010 and June 2017, 2021 patients were diagnosed with gastric cancer and underwent curative resection with adjuvant chemotherapy at our institution. Of 1461 patients with stage IB-III gastric cancer, 825 received TS-1 and 636 received XELOX as adjuvant chemotherapy. We retrospectively reviewed their medical records and analyzed the postoperative 5-year overall survival (OS) and disease-free survival (DFS) of these 2 groups. Results: The patients in the XELOX group had more advanced stage of cancer than the TS-1 group (stages III and II: 56.6% and 43.1%, respectively, in XELOX and 35.3% and 57.0% in TS-1; P < .001). The DFS did not differ significantly between the 2 study groups at any pathologic stage. The OS differed significantly only at pathologic stages IIA (P = .024) and IIB (P = .015). In a multivariate analysis of stage II patients, type of regimen was an independent prognostic factor of OS (XELOX vs TS-1; hazard ratio: 0.47, 95% confidence interval: 0.25-0.89, P = .021). Conclusion: There were similar long-term efficacies between these 2 regimens in advanced gastric cancer patients who underwent curative surgery. However, the XELOX regimen might be favorable for OS of stage II patients.

Survival outcomes of adjuvant taxanes, platinum plus fluoropyrimidines versus platinum and fluoropyrimidines for gastric cancer patients after D2 gastrectomy: a retrospective propensity score-matched analysis

BACKGROUND

To evaluate whether the addition of taxanes to platinum and fluoropyrimidines in adjuvant chemotherapy would result in longer survival than platinum plus fluoropyrimidines in gastric cancer patients who received D2 gastrectomy.

METHODS

Data of patients with gastric adenocarcinoma who received D2 gastrectomy and adjuvant chemotherapy with platinum plus fluoropyrimidines or taxanes, platinum plus fluoropyrimidines was retrospectively collected and analyzed. 1:1 Propensity score matching analysis was used to balance baseline characteristics between two groups. Survival curves were estimated using Kaplan-Meier method, and the differences were compared using the log-rank test.

RESULTS

Four hundred twenty-five patients in the platinum plus fluoropyrimidines group and 177 patients in the taxanes, platinum plus fluoropyrimidines group were included into analysis. No statistical differences in disease-free survival and overall survival were observed between two groups. After propensity score matching, 172 couples of patients were matched, the baseline characteristics were balanced. The median disease-free survival were 15.8 months (95% CI, 9.3~22.4) in the platinum plus fluoropyrimidines group and 22.6 months (95% CI, 15.9~29.4) in the taxanes, platinum plus fluoropyrimidines group (HR = 0.63; 95% CI, 0.48~0.85; P = 0.002). The median overall survival was 25.4 months for patients in the platinum plus fluoropyrimidines group (95% CI, 19.4~31.3) and 33.8 months (95% CI, 23.5~44.2) for those in the taxanes, platinum plus fluoropyrimidines group (HR = 0.68; 95% CI, 0.53-0.87; log-rank test, P = 0.002).

CONCLUSIONS

For gastric adenocarcinoma patients, the adjuvant triplet combination of taxanes, platinum, and fluoropyrimidines regimen after D2 gastrectomy was superior to platinum plus fluoropyrimidines regimen in disease-free survival as well as overall survival.

TRIAL REGISTRATION

This project has been registered in the Chinese Clinical Trial Registry ( ChiCTR1800019978 ).

Comparison of S-1-based vs. capecitabine-based adjuvant chemotherapy for patients with gastric cancer: a systematic review and meta-analysis

BACKGROUND

S-1-based and capecitabine-based adjuvant treatments are proved efficacious for patients with gastric cancer, but conventional meta-analyses of the direct comparisons between two alternative adjuvant regimens to resection of GC have not been attempted.

AIM

The aim of this review was to compare the disease-free survival, overall survival and adverse events in patients receiving the S-1- and capecitabine-based adjuvant chemotherapies for treatment of gastric cancer (GC) patients undergoing resection.

METHODS

A search of the academic literature was performed in PUBMED, SCOPUS, CENTRAL and EMBASE databases along with manual search in relevant journals for studies in English, to identify comparative studies comparing the effect of S-1-based chemotherapy and capecitabine-based adjuvant chemotherapy (AC), used in combination with surgical resection for treatment of gastric cancer. Both qualitative and quantitative analyses was carried out for all the included studies. The hazard ratios (HR) of disease-free survival (DFS) and overall survival (OS) were pooled using generic inverse variance method. The included studies were assessed for risk of bias using ROBINS-E (risk of bias in non-randomized studies of exposures) tool.

RESULTS

Seven retrospective cohort studies, two prospective cohort studies and one randomized clinical trial were included. Both S-1- and capecitabine-based adjuvant chemotherapy for treatment of stage 2 or 3 gastric cancer had similar effects on the 3-year and 5-year DFS rates, overall survival and adverse events in the included studies. There was no difference in the adjusted hazard ratios (HR) of OS and DFS (0.86 95% CI (0.68, 1.09); p = 0.21 and 0.96 95% CI (0.75, 1.24), respectively). Oral mucositis was increasingly associated with S-1-based AC, while incidences of adverse events such as neutropenia, anaemia and thrombocytopenia were similar to those of capecitabine-based regimen. The quality of the included studies was found to be low to moderate.

CONCLUSION

S-1- and capecitabine-based adjuvant chemotherapies can be used interchangeably as an adjuvant chemotherapeutic regimen postradical gastrectomy with D2 lymph node dissection.

Surgery alone, adjuvant tegafur/gimeracil/octeracil (S-1), or platinum-based chemotherapies for resectable gastric cancer: real-world experience and a propensity score matching analysis

Background

Adjuvant chemotherapy has changed the paradigm in resectable gastric cancer. S-1 is an oral chemotherapeutic with promising efficacy in Asia. However, comparisons with close observation or platinum-based doublets post D2 gastrectomy have been less reported, notably on real-world experiences.

Methods

We retrospectively evaluated patients with D2-dissected stage IB-III gastric cancer who received S-1 (S-1, n = 67), platinum-based doublets (P, n = 145) and surgery with close observation (OBS, n = 221) from Jan 2008 to Oct 2018. A propensity score matching was used to compare for recurrence-free (RFS) and overall survivals (OS) in patients who had a locally-advanced disease (T3–4 or lymph node-positive). Adverse reactions, dosage, and associated factors for S-1 are also discussed.

Results

In a median follow-up time of 51.9 months, adjuvant S-1 monotherapy was associated with an intermediate survival as compared with P and OBS (median RFS/OS: S-1 vs. P, 20.9/35.8 vs. 31.2/50.5 months, HR = 1.76/2.14, p = 0.021/0.008; S-1 vs. OBS, 24.4/40.2 vs. 20.7/27.0 months, HR = 0.62/0.55, p = 0.041/0.024). The survival differences were more prominent in patients with N2–3 diseases. S-1 was well-tolerated with a relative dose intensity of 73.6%, a median duration of 8.3 months and associated with less adverse reactions as compared with P. S-1 monotherapy was selected by physicians based on age, lymph node stage, serum carcinoembryonic antigen and disease stage.

Conclusions

Adjuvant S-1 correlated with intermediate survival outcomes between OBS and P but conferred fewer adverse reactions as compared with P. Patients with a moderate risk of recurrence had comparable survivals when treated with S-1 while platinum-based doublets were favored in advanced cases. The study provides additional information about adjuvant S-1 in patients with selected risk of recurrence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08487-z.

Procyanidin B2 induces apoptosis and autophagy in gastric cancer cells by inhibiting Akt/mTOR signaling pathway

Background

Procyanidin B2 (PB2), a unique component of the grape seed and other medicinal plants. PB2 has shown wide anticancer activity in various human cancer cells. However, it remains unclear about the biological effects and associated mechanisms of PB2 on gastric cancer cells.

Methods

Cell proliferation was measured by CCK8 assay, and cellular lactate dehydrogenase (LDH) release was measured in the culture medium. Cellular apoptosis was observed via TUNEL staining assay and measured by caspase-3 and -9 activities. Autophagy was observed by LC3 staining. Western blot analysis was performed to verify autophagy-associated proteins (Beclin1 and Atg5) and Akt-mTOR pathway.

Results

PB2 reduced the viability of BGC-823 and SGC-7901 cells in a concentration-dependent manner. Furthermore, PB2 induced increased apoptosis rate of gastric cancer cells and enhanced caspase-3 and -9 activities. Simultaneously, PB2 triggered autophagy in gastric cancer cells, with enhanced LC3 staining and increased expression of Beclin1 and Atg5, while the inhibition of autophagy by 3-MA reversed the PB2-induced suppression on cell viability. In addition, PB2 significantly decreased p-Akt and p-mTOR protein expression of gastric cancer cells.

Conclusion

PB2 exerts anti-proliferative and apoptotic effects and induces autophagy by modulating Akt/mTOR signaling pathway. PB2 may be developed as a potential therapeutic drug for gastric cancer.

Loss of RNF43 Function Contributes to Gastric Carcinogenesis by Impairing DNA Damage Response

BACKGROUND & AIMS

RING finger protein 43 (RNF43) is a tumor suppressor that frequently is mutated in gastric tumors. The link between RNF43 and modulation of Wingless-related integration site (WNT) signaling has not been shown clearly in the stomach. Because mutations in RNF43 are highly enriched in microsatellite-unstable gastric tumors, which show defects in DNA damage response (DDR), we investigated whether RNF43 is involved in DDR in the stomach.

METHODS

DDR activation and cell viability upon γ-radiation was analyzed in gastric cells where expression of RNF43 was depleted. Response to chemotherapeutic agents 5-fluorouracil and cisplatin was analyzed in gastric cancer cell lines and xenograft tumors. In addition, involvement of RNF43 in DDR activation was analyzed upon Helicobacter pylori infection in wild-type and Rnf43^ΔEx8 mice. Furthermore, a cohort of human gastric biopsy specimens was analyzed for RNF43 expression and mutation status as well as for activation of DDR.

RESULTS

RNF43 depletion conferred resistance to γ-radiation and chemotherapy by dampening the activation of DDR, thereby preventing apoptosis in gastric cells. Upon Helicobacter pylori infection, RNF43 loss of function reduced activation of DDR and apoptosis. Furthermore, RNF43 expression correlated with DDR activation in human gastric biopsy specimens, and RNF43 mutations found in gastric tumors conferred resistance to DNA damage. When exploring the molecular mechanisms behind these findings, a direct interaction between RNF43 and phosphorylated H2A histone family member X (γH2AX) was observed.

CONCLUSIONS

We identified a novel function for RNF43 in the stomach as a regulator of DDR. Loss of RNF43 function in gastric cells confers resistance to DNA damage-inducing radiotherapy and chemotherapy, suggesting RNF43 as a possible biomarker for therapy selection.

Synergistic antitumor activity of a DLL4/VEGF bispecific therapeutic antibody in combination with irinotecan in gastric cancer

Notch signaling has been identified as a critical pathway in gastric cancer (GC) progression and metastasis, and inhibition of Delta-like ligand 4 (DLL4), a Notch ligand, is suggested as a potent therapeutic approach for GC. Expression of both DLL4 and vascular endothelial growth factor receptor 2 (VEGFR2) was similar in the malignant tissues of GC patients. We focused on vascular endothelial growth factor (VEGF), a known angiogenesis regulator and activator of DLL4. Here, we used ABL001, a DLL4/VEGF bispecific therapeutic antibody, and investigated its therapeutic effect in GC. Treatment with human DLL4 therapeutic antibody (anti-hDLL4) or ABL001 slightly reduced GC cell growth in monolayer culture; however, they significantly inhibited cell growth in 3D-culture, suggesting a reduction in the cancer stem cell population. Treatment with anti-hDLL4 or ABL001 also decreased GC cell migration and invasion. Moreover, the combined treatment of irinotecan with anti-hDLL4 or ABL001 showed synergistic antitumor activity. Both combination treatments further reduced cell growth in 3D-culture as well as cell invasion. Interestingly, the combination treatment of ABL001 with irinotecan synergistically reduced the GC burden in both xenograft and orthotopic mouse models. Collectively, DLL4 inhibition significantly decreased cell motility and stem-like phenotype and the combination treatment of DLL4/VEGF bispecific therapeutic antibody with irinotecan synergistically reduced the GC burden in mouse models. Our data suggest that ABL001 potentially represents a potent agent in GC therapy. Further biochemical and pre-clinical studies are needed for its application in the clinic.

Characterization of FDG PET Images Using Texture Analysis in Tumors of the Gastro-Intestinal Tract: A Review

Radiomics or textural feature extraction obtained from positron emission tomography (PET) images through complex mathematical models of the spatial relationship between multiple image voxels is currently emerging as a new tool for assessing intra-tumoral heterogeneity in medical imaging. In this paper, available literature on texture analysis using FDG PET imaging in patients suffering from tumors of the gastro-intestinal tract is reviewed. While texture analysis of FDG PET images appears clinically promising, due to the lack of technical specifications, a large variability in the implemented methodology used for texture analysis and lack of statistical robustness, at present, no firm conclusions can be drawn regarding the predictive or prognostic value of FDG PET texture analysis derived indices in patients suffering from gastro-enterologic tumors. In order to move forward in this field, a harmonized image acquisition and processing protocol as well as a harmonized protocol for texture analysis of tumor volumes, allowing multi-center studies excluding statistical biases should be considered. Furthermore, the complementary and additional value of CT-imaging, as part of the PET/CT imaging technique, warrants exploration.

Comparison of Docetaxel + Oxaliplatin + S-1 vs Oxalipatin + S-1 as Neoadjuvant Chemotherapy for Locally Advanced Gastric Cancer: A Propensity Score Matched Analysis

Background

What is the optimal neoadjuvant chemotherapy (NAC) regimen for locally advanced gastric cancer (LAGC) remains debatable. The objective of this study was to compare the efficacy of docetaxel+oxaliplatin+S-1 (DOS) vs oxaliplatin+S-1 (SOX) as NAC for LAGC.

Methods

Data of 248 LAGC patients who received either DOS or SOX as NAC in our hospital between January 2010 and January 2018 were reviewed retrospectively. Propensity score matched (PSM) analysis was applied to minimize the selection bias in both groups. Prognostic factors were screened by univariate and multivariate Cox regression analyses.

Results

Of the 248 LAGC patients included, 180 patients were subjected to the PSM analysis. Patients in DOS group showed a better tumor response to NAC, higher radical resection rate and R0 resection rate than those in SOX group. The overall survival (OS) rate in DOS group was better than that in SOX group, although the overall incidence of Grade 3/4 NAC-related toxicity in DOS group was higher, as represented by leukopenia and neutropenia. Multivariate analysis revealed that the NAC regimen, cTNM stage and the R0 resection rate were independent prognostic factors. In addition, patients with TLND less than 16 population showed a worse OS rate. Subgroup analysis indicated that patients benefited from the addition of docetaxel regardless of the clinical T stage, but those with high clinical N stages (N2-3) did not.

Conclusion

DOS is a safe and feasible NAC regimen for LAGC, which is worth popularizing in clinical practice.

Suppression of FAK by nexrutine inhibits gastric cancer progression

AIM

Nexrutine, an herbal extract of Phellodendron amurense, has been found to play a tumor-suppressive role in many cancers. However, its role in the pathogenesis of gastric cancer remains unclear.

MATERIALS AND METHODS

Gastric cancer cells (SGC-7901 and MGC-803) were treated with nexrutine, and cell proliferation, invasion and apoptosis were analyzed. And the MGC-803 cells-derived xenograft mouse models were fed pelleted diet containing 600 mg/kg nexrutine for 21 days after inoculation. Mechanically, we focused on the influences of nexrutine on the levels and activation of STAT3 and NF-κB as well as their upstream regulator FAK. Additionally, we further verified whether nexrutine affected the proliferation, invasion and apoptosis of gastric cancer cells via FAK by upregulating FAK expression before nexrutine treatment.

KEY FINDINGS

We found nexrutine inhibited the viability, invasion, and expression levels of PCNA, CyclinD1 and Bcl-2, promoted the apoptosis and Bax expression, decreased levels of STAT3, phospho-STAT3, NF-κB p65, phospho-p65, FAK and phospho-FAK in gastric cancer cells. Overexpression of FAK reversed the impacts of nexrutine on the levels of STAT3, phospho-STAT3, NF-κB p65, phospho-p65, as well as the malignant characteristics of gastric cancer cells. Moreover, nexrutine suppressed tumor volumes and weights, and decreased expression and phosphorylation of FAK, STAT3 and NF-κB p65 in vivo.

SIGNIFICANCE

Nexrutine inhibited the malignant progression of gastric cancer via negatively regulating STAT3/NF-κB signaling pathway by suppressing FAK expression and activation.