Validity of neoadjuvant chemotherapy with docetaxel, cisplatin, and S-1 for resectable locally advanced gastric cancer

Prediction of the mechanism for the combination of diallyl trisulfide and cisplatin against gastric cancer: a network pharmacology study and pharmacological evaluation

Background: In this research, we aimed to explore the efficacy of diallyl trisulfide (DATS) combined with cisplatin (DDP) for gastric cancer treatment and its underlying mechanism based on network pharmacology. Methods: First, the pharmacological mechanism by which DATS combined with DDP acts against gastric cancer was predicted using network pharmacology. The TTD, GeneCards, and OMIM databases were used to extract drug and disease targets. The David Bioinformatics Resources 6.8 database was used to conduct GO and KEGG analyses. We investigated the efficacy of DATS combined with DDP against gastric cancer in SGC7901 cells and a xenograft model. Furthermore, the specific mechanism of DATS combined with DDP, inferred by network pharmacology, was identified by Western blotting and immunohistochemistry. Results: The combination of DDP and DATS significantly increased cytotoxicity and cell apoptosis compared to the DATS or DDP treatment group in vitro. In addition, continuous intraperitoneal injection of DATS markedly improved the tumor inhibitory effect of DDP in the SGC-7901 tumor-bearing mouse model. Furthermore, network pharmacology and experimental validation studies revealed that the combination of DATS and DDP synergistically enhanced antitumor activity by regulating endoplasmic reticulum stress and inhibiting STAT3/PKC-δ and MAPK signaling pathways. Conclusion: Our study showed that the combination of DATS and DDP could exert outstanding therapeutic effects in gastric cancer. Moreover, network pharmacology coupled with experimental validation revealed the molecular mechanisms of combination therapy for gastric cancer. This study offers a new adjuvant strategy based on DATS and DDP for the treatment of gastric cancer.

The validity of neoadjuvant chemotherapy with paclitaxel plus S-1 is not inferior to that of SOX regimen for locally advanced gastric cancer: an observational study

BACKGROUND

Paclitaxel plus S-1(PTXS) has shown definite efficacy for advanced gastric cancer. However, the efficacy and safety of this regimen in neoadjuvant setting for locally advanced gastric cancer (LAGC) are unclear. This study aimed to compare the efficacy of neoadjuvant chemotherapy (NAC) PTXS and oxaliplatin plus S-1 (SOX) regime for patients with LAGC.

METHODS

A total of 103 patients with LAGC (cT3/4NanyM0/x) who were treated with three cycles of neoadjuvant SOX regimen (n = 77) or PTXS regimen (n = 26) between 2011 and 2017 were enrolled in this study. NAC-related clinical response, pathological response, postoperative complication, and overall survival were analyzed between the groups.

RESULTS

The baseline data did not differ significantly between both groups. After NAC, the disease control rate of the SOX group (94.8%) was comparable with that of the PTXS group (92.3%) (p = 0.641). Twenty-three cases (29.9%) in the SOX group and 10 cases (38.5%) in the PTX group got the descending stage with no statistical difference (p = 0.417). No significant differences were observed in the overall pathological response rate and the overall postoperative complication rate between the two groups (p > 0.05). There were also no differences between groups in terms of 5-year overall and disease-free survival (p > 0.05).

CONCLUSIONS

The validity of NAC PTXS was not inferior to that of SOX regimen for locally advanced gastric cancer in terms of treatment response and overall survival. PTXS regimen could be expected to be ideal neoadjuvant chemotherapy for patients with LAGC and should be adopted for the test arm of a large randomized controlled trial.

MiR-522-3p Targets Transcription Factor 4 to Overcome Cisplatin Resistance of Gastric Cells

Gastric cancer (GC) is a malignancy originating from gastric epithelial tissue. Chemoresistance to cisplatin (DDP) often leads to chemotherapy failure in GC. Previously, miR-522 was found to be associated with chemoresistance in GC cells. Thus, we attempted to clarify miR-522-3p's role underlying chemoresistance of GC cells. RT-qPCR measured the miR-522-3p levels in untreated and DDP-treated AGS cells. RT-qPCR and Western blotting detected transcription factor 4 (TCF4) mRNA and protein levels in GC cells. AGS and AGS/DDP cell proliferation were detected by the colony formation assay. Flow cytometry analysis detected AGS and AGS/DDP cell apoptosis. Bioinformatics and dual luciferase reporter assays predicted and verified the relationship between miR-522-3p and TCF4. Rescue experiments further clarified the regulatory patterns of miR-522-3p/TGF4 in GC cells. miR-522-3p presented a downregulation in GC cells and was positively affected by DDP. TCF4 presented elevation in GC cells and was negatively affected by DDP. Mechanistically, miR-522-3p targeted TCF4 to suppress TCF4 gene expression. miR-522-3p overexpression suppressed GC cell proliferation and resistance to DDP and GC cell apoptosis was facilitated. TCF4 overexpression facilitated GC cell proliferation and resistance to DDP while repressing GC cell apoptosis. TCF4 elevation rescued changes in GC cell proliferation, apoptosis, and chemoresistance due to miR-522-3p overexpression. To sum up, miR-522-3p suppresses GC cell malignancy and resistance to DDP via targeting TCF4. Our research may provide a new biomarker for GC diagnosis and a novel direction for GC chemotherapy.

Neoadjuvant Bevacizumab Plus Docetaxel/Cisplatin/Capecitabine Chemotherapy in Locally Advanced Gastric Cancer Patients: A Pilot Study

Background

Bevacizumab (BEV) plus chemotherapy as a neoadjuvant regimen presents good efficacy in patients with locally advanced cancer. However, its role in patients with locally advanced gastric cancer (LAGC) is not clear. Thus, the study aimed to assess the efficacy and safety of neoadjuvant BEV plus chemotherapy in patients with LAGC.

Methods

Twenty resectable patients with LAGC who received BEV plus docetaxel/cisplatin/capecitabine (DCC) chemotherapy for 3 cycles with 21 days as one cycle as neoadjuvant regimen were involved. Besides, their treatment response, survival profiles, and adverse events were assessed.

Results

In total, two (10.0%), 9 (45.0%), 8 (40.0%), and 1 (5.0%) patients achieved complete remission, partial remission, stable disease, and progressive disease (PD) according to imaging evaluation, which resulted in 55.0% of objective response rate and 95.0% of disease control rate, respectively. Moreover, the number of patients with pathological response grades 1, 2, and 3 was 8 (40.0%), 8 (40.0%), and 3 (15.0%); while 1 (5.0%) patient did not receive surgery due to PD, thus the data of this patient was not assessable. Meanwhile, 18 (90.0%) patients achieved R0 resection. Regarding survival profile, the median disease-free survival or overall survival were both not reached. The 1-year, 2-, and 3-year disease-free survival rates were 88.8, 80.7, and 67.3%. Meanwhile, the 1-, 2-, and 3-year overall survival rates were 100.0%, 75.8%, and 75.8%, respectively. Additionally, the main adverse events were anemia (90.0%), alopecia (90.0%), leukopenia (70.0%), and anorexia (65.0%). Indeed, most adverse events were of grade 1 or 2 and were manageable.

Conclusion

Neoadjuvant BEV plus DCC chemotherapy presents a favorable pathological response and survival profile with acceptable safety in patients with LAGC.

Oxidative stress activates NORAD expression by H3K27ac and promotes oxaliplatin resistance in gastric cancer by enhancing autophagy flux via targeting the miR-433-3p

Oxaliplatin resistance undermines its curative effects on cancer and usually leads to local recurrence. The oxidative stress induced DNA damage repair response is an important mechanism for inducing oxaliplatin resistance by activating autophagy. ELISA is used to detect target genes expression. TMT-based quantitative proteomic analysis was used to investigate the potential mechanisms involved in NORAD interactions based on GO analysis. Transwell assays and apoptosis flow cytometry were used for biological function analysis. CCK-8 was used to calculate IC50 and resistance index (RI) values. Dual-luciferase reporter gene assay, RIP and ChIP assays, and RNA pull-down were used to detect the interaction. Autophagy flux was evaluated using electron microscope and western blotting. Oxidative stress was enhanced by oxaliplatin; and oxaliplatin resistance gastric cancer cell showed lower oxidative stress. TMT labeling showed that NORAD may regulate autophagy flux. NORAD was highly expressed in oxaliplatin-resistant tissues. In vitro experiments indicate that NORAD knockdown decreases the RI (Resistance Index). Oxaliplatin induces oxidative stress and upregulates the expression of NORAD. SGC-7901 shows enhanced oxidative stress than oxaliplatin-resistant cells (SGC-7901-R). NORAD, activated by H3K27ac and CREBBP, enhanced the autophagy flux in SGC-7901-R to suppress the oxidative stress. NORAD binds to miR-433-3p and thereby stabilize the ATG5- ATG12 complex. Our findings illustrate that NORAD, activated by the oxidative stress, can positively regulate ATG5 and ATG12 and enhance the autophagy flux by sponging miR-433-3p. NORAD may be a potential biomarker for predicting oxaliplatin resistance and mediating oxidative stress, and provides therapeutic targets for reversing oxaliplatin resistance.

Lidocaine alleviates cisplatin resistance and inhibits migration of MGC-803/DDP cells through decreasing miR-10b

Although chemotherapy is one of the effective means of treating gastric cancer, the resistance of chemotherapeutic drugs has followed. And the mechanisms of resistance are not completely clear. The main aim of this article was to develop a kind of drug that could reduce the resistance of cisplatin on gastric cancer cells. The MGC-803 and MGC-803/DDP cells were treated by cisplatin for 48 h and Lidocaine (Lido) for 24 h. Cell viability, apoptosis, migration and invasion were tested by cell counting kit-8 (CCK-8) assay, apoptosis assay, western blot, migration and invasion assay. After MGC-803/DDP cells were transfected for 48 h, the expression of microRNA-10b (miR-10b) were detected by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Activation of AKT/mTOR and β-catenin pathways was tested by western blot. Cisplatin caused MGC-803 and MGC-803/DDP cell apoptosis, and MGC-803/DDP cells possessed higher cisplatin resistance than MGC-803 cells. Lido reduced the cisplatin resistance of MGC-803/DDP cells. Besides, Lido inhibited MGC-803/DDP cell migration and invasion. In addition, Lido declined cisplatin resistance by down-regulating miR-10b. Lido also repressed AKT/mTOR and β-catenin pathway by down-regulating miR-10b. This article explained the role of Lido in cisplatin resistance in MGC-803/DDP cells. Furthermore, Lido weakened the cisplatin resistance in MGC-803/DDP cells at least in part through decreasing the expression of miR-10b.

Cisplatin resistance in gastric cancer cells is involved with GPR30-mediated epithelial-mesenchymal transition

Cisplatin is the major chemotherapeutic drug in gastric cancer, particularly in treating advanced gastric cancer. Tumour cells often develop resistance to chemotherapeutic drugs, which seriously affects the efficacy of chemotherapy. GPR30 is a novel oestrogen receptor that is involved in the invasion, metastasis and drug resistance of many tumours. Targeting GPR30 has been shown to increase the drug sensitivity of breast cancer cells. However, few studies have investigated the role of GPR30 in gastric cancer. Epithelial‐mesenchymal transition (EMT) has been shown to be associated with the development of chemotherapeutic drug resistance. In this study, we demonstrated that GPR30 is involved in cisplatin resistance by promoting EMT in gastric cancer. GPR30 knockdown resulted in increased sensitivity of different gastric cancer (GC) cells to cisplatin and alterations in the epithelial/mesenchymal markers. Furthermore, G15 significantly enhanced the cisplatin sensitivity of GC cells while G1 inhibited this phenomenon. In addition, EMT occurred when AGS and BGC‐823 were treated with cisplatin. Down‐regulation of GPR30 with G15 inhibited this transformation, while G1 promoted it. Taken together, these results revealed the role of GPR30 in the formation of cisplatin resistance, suggesting that targeting GPR30 signalling may be a potential strategy for improving the efficacy of chemotherapy in gastric cancer.

Outcomes of preoperative S-1 and docetaxel combination chemotherapy in patients with locally advanced gastric cancer

PURPOSE

The therapeutic outcomes of stage III gastric cancer patient receiving D2 gastrectomy and adjuvant chemotherapy remain unsatisfactory. To improve the long-term outcomes in this population, the combination of docetaxel and S-1 (DS) therapy can be expected to be a useful regimen as neoadjuvant chemotherapy (NAC). This study aimed to prospectively evaluate the efficacy of NAC-DS for clinical stage III gastric cancer.

METHODS

Between January 2010 and December 2013, 26 patients were enrolled. Patients with clinical stage III gastric cancer received two courses of docetaxel 40 mg/m² on day 1, 15 and S-1 40 mg/m² bid orally on day 1-7, 15-21 every 4 weeks, followed by radical D2 gastrectomy. Short- and long-term outcomes were evaluated. This study was approved by the ethics committee of Yokohama City University, and was registered in the University Hospital Medical Information Network (UMIN) database (ID: 000011521).

RESULTS

Of 26 patients, 24 (92.3%) patients completed two courses of NAC. After NAC-DS, Grade 3 neutropenia was observed in 5 (19.2%) patients including one patient with febrile neutropenia, anemia in 1 (3.8%) patient and diarrhea in 1 (3.8%) patient. All patients underwent R0 gastrectomy and pathological response was found in 15 (57.6%) patients. Postoperatively, Clavien-Dindo grade II complication occurred in 8 (30.7%) patients and no mortality was observed. The 5-year overall survival (OS) was 57.7%, median OS was 78.7 months and recurrence free survival (RFS) was 49.0%, median RFS was 45.4 months with 66.5 months median follow-up. Pathological response (HR = 0.091, 95% CI 0.011-0.730, p = 0.016) and > 5% body weight loss before NAC-DS (HR = 0.133, 95% CI 0.023-0.765, p = 0.024) were independent risk factors for recurrence, > 5% body weight loss before NAC-DS (HR = 0.133, 95% CI 0.023-0.765, p = 0.024) were independent risk factors for overall survival by multivariate analysis.

CONCLUSIONS

NAC-DS demonstrated acceptable toxicity with a high R0 resection rate in clinical stage III gastric cancer patients, especially in patients with good nutritional status. Further prospective study is warranted to compare the long-term outcomes between with and without NAC-DS.

Comprehensive bioinformatics analysis of lncRNAs in gastric cancer

Long non-coding RNAs (lncRNAs) have been generally considered to serve important roles in various types of cancer, including gastric cancer. However, a comprehensive understanding of lncRNAs in gastric cancer requires further study. The present study performed an in-depth study revealed 50 differently expressed lncRNAs. The changed cellular pathways and biological process in gastric cancer were determined. To further confirm the functions of the differently expressed lncRNAs, co-expression networks were constructed between the lncRNAs and mRNA; this lead to the identification of 6 modules, which participated in various cellular pathways. In addition, 2 lncRNAs were identified which were associated with clinical outcome. The biological analysis and experimental evidence suggested that LINC00982 inhibited, while LL22NC03-N14H11.1 promoted the proliferation of gastric cancer cells. These lncRNAs may be considered as potential prognostic factor in gastric cancer.

Prognostic analysis of stage III gastric cancer after curative surgery according to the newest TNM classification

AIM

To study the prognostic factors of gastric cancer (GC) patients who were classified with stage III disease according to the newest TNM classification.

METHODS

This study retrospectively enrolled 279 patients who underwent radical gastrectomy from January 2012 to December 2014 at our hospital and who were diagnosed with stage III GC according to the new 8th edition of the TNM classification. The patient data that were collected included age, sex, pathological parameters, survival, lymph node ratio, neo-adjuvant chemotherapy with oxaliplatin and S-1, and operation type. The characteristics, survival, and prognostic factors of the patients were analyzed by univariate and multivariate analyses.

RESULTS

The median OS of the patients after curative surgery was 19 months, and the 3-year survival rate (3-YSR) was 25.3%. A univariate analysis showed that tumor location (P = 0.01), neo-adjuvant chemotherapy (P = 0.005), pathological T stage (P = 0.002), pathological N stage (P < 0.001), lymph node ratio (LNR) (P < 0.001), and operation type (P = 0.032) were significantly associated with overall survival. A multivariate analysis revealed that neo-adjuvant chemotherapy (P = 0.009), pathological T stage (P = 0.012), and LNR (P < 0.001) were independent prognostic factors.

CONCLUSIONS

Neo-adjuvant chemotherapy, pathological T stage, and LNR were independent prognostic factors for the overall survival of patients with stage III GC. The neo-adjuvant chemotherapy with oxaliplatin and S-1 can be used for the patients to improve their survival.