Prognostic characteristics and clinical response to immunotherapy targeting programmed cell death 1 for patients with advanced gastric cancer with liver metastases.

Background: The specific efficacy of immunotherapy for patients with liver metastases of gastric cancer is unclear. This study set out to explore the treatment response and related prognostic factors for patients with liver metastases of gastric cancer treated with immunotherapy. Patients and methods: This retrospective cohort study included 135 patients with unresectable advanced gastric cancer. According to the presence of liver metastases and/or first-line treatment with immunotherapy, patients were divided into the following three groups: I-LM(-) group(patients without liver metastases treated with immunotherapy, n=66), I-LM(+) group(patients with liver metastases treated with immunotherapy, n=36), C-LM(+) group(patients with liver metastases treated with chemotherapy and/or target therapy, n=33). Cox regression analyses were used to identify factors associated with survival in all patients and the three groups, respectively. Results: For the patients with liver metastases treated with immunotherapy, multivariate analysis showed that only the presence of peritoneal metastases was significantly associated with shorter PFS [hazard ratios (HR), 3.23; 95% CI, 1.12-9.32; P=0.030] and the patients with peritoneal metastases had shorter median PFS than patients without peritoneal metastases(3.1 vs 18.4 months; P=0.004), while the objective response rate was 100% in patients with HER2-positive (2 complete radiographic responses and 2 partial responses; 3 of 4 patients were still ongoing benefits [median follow-up time, 15.3 months ; interquartile range(IQR), 6.3-17.9 months]). Conclusions: The findings suggest that patients with various types of gastric cancer liver metastases respond differently to immune checkpoint inhibitors, HER2-positive patients may derive clinical benefits from immune checkpoint inhibitors, while the presence of peritoneal metastases is associated with resistance.

Tumor-Targeted Polydopamine-Based Nanoparticles for Multimodal Mapping Following Photothermal Therapy of Metastatic Lymph Nodes.

Purpose: Lymphadenectomy with lymph node (LN) mapping is essential for surgical removal of solid tumors. Existing agents do not provide accurate multimodal mapping and antitumor therapy for metastatic LNs; therefore, we fabricated a polydopamine (PDA) nanoparticle (NP)-based tumor-targeted LN mapping agent capable of multimodal mapping and guided photothermal therapy (PTT) for metastatic LNs. Materials and Methods: PDA NPs modified with polyethylene glycol (PEG) were obtained by polymerization under alkaline conditions. The PEG-PDA NPs were loaded with the circular tripeptide Arg-Gly-Asp (cRGD) to achieve tumor-targeting capacity and with the fluorescent dye IR820 and magnetic resonance imaging (MRI) contrast Gd(NH2)2 for in situ detection. The resulting cRGD-PEG-PDA@IR820/Gd(NH2)2 (cRGD-PPIG) NPs were tested for their biosafety and metastatic LN mapping ability. They were drained specifically into LNs and selectively taken up by gastric MKN45 cells via αvß3 integrin-mediated endocytosis. Results: This phenomenon enabled MR/optical/near-infrared fluorescence multimodal metastatic LN mapping, guiding the creation of accurate and highly efficient PTT for gastric cancer metastatic LNs in mice. Conclusion: In summary, we fabricated tumor-targeted cRGD-PPIG NPs with MR/optical/near-infrared fluorescence multimodal metastatic LN mapping capacity for surgery and efficient PTT guidance post-surgery.

Graphene oxide (GO)-based nanosheets with combined chemo/photothermal/photodynamic therapy to overcome gastric cancer (GC) paclitaxel resistance by reducing mitochondria-derived adenosine-triphosphate (ATP).

BACKGROUND: Paclitaxel (PTX) has been suggested to be a promising front-line drug for gastric cancer (GC), while P-glycoprotein (P-gp) could lead to drug resistance by pumping PTX out of GC cells. Consequently, it might be a hopeful way to combat drug resistance by inhibiting the out-pumping function of P-gp. RESULTS: In this study, we developed a drug delivery system incorporating PTX onto polyethylene glycol (PEG)-modified and oxidized sodium alginate (OSA)-functionalized graphene oxide (GO) nanosheets (NSs), called PTX@GO-PEG-OSA. Owing to pH/thermal-sensitive drug release properties, PTX@GO-PEG-OSA could induced more obvious antitumor effects on GC, compared to free PTX. With near infrared (NIR)-irradiation, PTX@GO-PEG-OSA could generate excessive reactive oxygen species (ROS), attack mitochondrial respiratory chain complex enzyme, reduce adenosine-triphosphate (ATP) supplement for P-gp, and effectively inhibit P-gp's efflux pump function. Since that, PTX@GO-PEG-OSA achieved better therapeutic effect on PTX-resistant GC without evident toxicity. CONCLUSIONS: In conclusion, PTX@GO-PEG-OSA could serve as a desirable strategy to reverse PTX's resistance, combined with chemo/photothermal/photodynamic therapy.

Survival analysis of elderly patients over 65 years old with stage II/III gastric cancer treated with adjuvant chemotherapy after laparoscopic D2 gastrectomy: a retrospective cohort study.

BACKGROUND: The benefits of adjuvant chemotherapy for elderly patients with gastric cancer (GC) remain unknown because elderly patients are underrepresented in most clinical trials. This study aimed to evaluate the effectiveness and complications of adjuvant chemotherapy in patients > 65 years of age after laparoscopic D2 gastrectomy. METHODS: This was a single-center retrospective cohort study of elderly patients (> 65 years) with stage II/III GC who underwent curative laparoscopic D2 gastrectomy with R0 resection between 2004 and 2018. The adjuvant chemotherapy regimens included monotherapy (oral capecitabine) and doublet chemotherapy (oral capecitabine plus intravenous oxaliplatin [XELOX] or intravenous oxaliplatin, leucovorin, and 5-fluorouracil [FOLFOX]). The data were retrieved from a prospectively registered database maintained at the Department of General Surgery in Nanfang Hospital, China. The patients were divided as surgery alone and surgery plus adjuvant chemotherapy (chemo group). The overall survival (OS), disease-free survival (DFS), chemotherapy duration, and toxicity were examined. RESULTS: There were 270 patients included: 169 and 101 in the surgery and chemo groups, respectively. There were 10 (10/101) and six (6/101) patients with grade 3+ non-hematological and hematological adverse events. The 1-/3-/5-year OS rates of the surgery group were 72.9%/51.8%/48.3%, compared with 90.1%/66.4%/48.6% for the chemo group (log-rank test: P = 0.018). For stage III patients, the 1-/3-/5-year OS rates of the surgery group were 83.7%/40.7%/28.7%, compared with 89.9%/61.2%/43.6% for the chemo group (log-rank test: P = 0.015). Adjuvant chemotherapy was significantly associated with higher OS (HR = 0.568, 95%CI: 0.357-0.903, P = 0.017) and DFS (HR = 0.511, 95%CI: 0.322-0.811, P = 0.004) in stage III patients. CONCLUSIONS: This study suggested that adjuvant chemotherapy significantly improves OS and DFS compared with surgery alone in elderly patients with stage III GC after D2 laparoscopic gastrectomy, with a tolerable adverse event profile.

Vitamin-B12-conjugated PLGA-PEG nanoparticles incorporating miR-532-3p induce mitochondrial damage by targeting apoptosis repressor with caspase recruitment domain (ARC) on CD320-overexpressed gastric cancer.

Among various methods, the use of targeting nucleic acid therapy is a promising method for inhibiting gastric cancer (GC) cells' rapid growth and metastasis abilities. In this study, vitamin B12-labeled poly (d,l-lactide-co-glycolide) and polyethylene glycol nanoparticles (PLGA-PEG-VB12 NPs) were developed for microRNAs-532-3p mimics incorporating as targeting gene delivery systems (miR-532-3p@PLGA-PEG-VB12 NPs) to fight against transcobalamin II (CD320)-overexpressed GC cells' progression. The PLGA-PEG-VB12 NPs with appropriate particle sizes and good bio-compatibility could be selectively delivered into CD320-overexpressed GC cells, and significantly decrease the expression of apoptosis repressor with caspase recruitment domain (ARC). Following that, more pro-apoptotic protein (Bax) flowed from cytoplasm into mitochondria to form Bax oligomerization, thus induced mitochondrial damage, including mitochondrial membrane potentials (MMPs) loss and excessive production of mitochondrial reactive oxygen species (mitoROS). Since that, mitochondrial permeability transition pore (mPTP) was opened, followed by induced more cytochrome c (Cyto C) releasing from mitochondria into cytosol, and finally activated caspase-depended cell apoptosis pathway. Therefore, our designed miR-532-3p@PLGA-PEG-VB12 NPs showed enhanced GC targeting ability, and could induce apoptosis through activating ARC/Bax/mitochondria-mediated apoptosis signaling pathway, finally remarkably suppressed proliferation of GC cells both in vitro and in vivo, which presented a promising treatment for GC.

Enhanced recovery after surgery for laparoscopic gastrectomy in gastric cancer: A prospective study.

BACKGROUND: Laparoscopic distal gastrectomy (LDG) has been highlighted for its safety and better short-term clinical outcomes in treating gastric cancer. However, only a slight reduction of the post-operative hospital stay was observed in gastric cancer patients undergoing LDG with conventional perioperative management, compared to patients undergoing open surgery. Thus, an enhanced recovery after surgery (ERAS) program for LDG is needed to further reduce the post-operative hospital stays. This prospective, open-label, single-arm cohort study aimed to assess the safety and efficacy of the ERAS program for gastric cancer patients undergoing LDG. MATERIAL AND METHODS: All patients with gastric cancer indicated for LDG were consecutively enrolled from December 2016 to January 2018. The ERAS program included short fasting time, effective perioperative pain management, early, goal-oriented ambulation, and oral feeding. The safety assessment was the incidence of post-operative complications, mortality, and readmission in 30 days. The primary efficacy assessment was recovery time defined by post-operative hospital stays and rehabilitative rate on post-operative day 4. RESULTS: Ninety-eight of 114 patients were finally enrolled. The incidence of post-operative complication, mortality, and readmission in 30 days was 20. 4%, 0%, 7.1%, respectively. The Clavien-Dindo grade III complication rate was 6.1%, while the pulmonary complication rate was 1% only. The median post-operative stay was 6 days (5.0-7.0 days), and the rehabilitative rate on post-operative day 4 was 78%. CONCLUSIONS: The ERAS program might be optimal perioperative management for gastric cancer patients after LDG without compromising safety. TRIAL NUMBER: NCT03016026.

Biodegradable hollow mesoporous organosilica nanotheranostics (HMON) for multi-mode imaging and mild photo-therapeutic-induced mitochondrial damage on gastric cancer.

BACKGROUND: CuS-modified hollow mesoporous organosilica nanoparticles (HMON@CuS) have been preferred as non-invasive treatment for cancer, as near infrared (NIR)-induced photo-thermal effect (PTT) and/or photo-dynamic effect (PDT) could increase cancer cells' apoptosis. However, the certain role of HMON@CuS-produced-PTT&PDT inducing gastric cancer (GC) cells' mitochondrial damage, remained unclear. Moreover, theranostic efficiency of HMON@CuS might be well improved by applying multi-modal imaging, which could offer an optimal therapeutic region and time window. Herein, new nanotheranostics agents were reported by Gd doped HMON decorated by CuS nanocrystals (called HMON@CuS/Gd). RESULTS: HMON@CuS/Gd exhibited appropriate size distribution, good biocompatibility, L-Glutathione (GSH) responsive degradable properties, high photo-thermal conversion efficiency (82.4%) and a simultaneous reactive oxygen species (ROS) generation effect. Meanwhile, HMON@CuS/Gd could efficiently enter GC cells, induce combined mild PTT (43-45 °C) and PDT under mild NIR power density (0.8 W/cm2). Surprisingly, it was found that PTT might not be the only factor of cell apoptosis, as ROS induced by PDT also seemed playing an essential role. The NIR-induced ROS could attack mitochondrial transmembrane potentials (MTPs), then promote mitochondrial reactive oxygen species (mitoROS) production. Meanwhile, mitochondrial damage dramatically changed the expression of anti-apoptotic protein (Bcl-2) and pro-apoptotic protein (Bax). Since that, mitochondrial permeability transition pore (mPTP) was opened, followed by inducing more cytochrome c (Cyto C) releasing from mitochondria into cytosol, and finally activated caspase-9/caspase-3-depended cell apoptosis pathway. Our in vivo data also showed that HMON@CuS/Gd exhibited good fluorescence (FL) imaging (wrapping fluorescent agent), enhanced T1 imaging under magnetic resonance imaging (MRI) and infrared thermal (IRT) imaging capacities. Guided by FL/MRI/IRT trimodal imaging, HMON@CuS/Gd could selectively cause mild photo-therapy at cancer region, efficiently inhibit the growth of GC cells without evident systemic toxicity in vivo. CONCLUSION: HMON@CuS/Gd could serve as a promising multifunctional nanotheranostic platform and as a cancer photo-therapy agent through inducing mitochondrial dysfunction on GC.

Nuclear MYH9-induced CTNNB1 transcription, targeted by staurosporin, promotes gastric cancer cell anoikis resistance and metastasis.

Rationale: Peritoneal metastasis predicts poor prognosis of gastric cancer (GC) patients, and the underlying mechanisms are poorly understood. Methods: The 2-DIGE, MALDI-TOF/TOF MS and single-cell transcriptome were used to detect differentially expressed proteins among normal gastric mucosa, primary GC and peritoneal metastatic tissues. Lentiviruses carrying shRNA and transcription activator-like effector nuclease technology were used to knock down myosin heavy chain 9 (MYH9) expression in GC cell lines. Immunofluorescence, immune transmission electron microscopy, chromatin fractionation, co-immunoprecipitation, and assays for chromatin immunoprecipitation, dual luciferase reporter, agarose-oligonucleotide pull-down, flow cytometry and cell anoikis were performed to uncover nuclear MYH9-induced ß-catenin (CTNNB1) transcription in vitro. Nude mice and conditional transgenic mice were used to investigate the findings in vivo. Results: We observed that MYH9 was upregulated in metastatic GC tissues and was associated with a poor prognosis of GC patients. Mechanistically, we confirmed that MYH9 was mainly localized in the GC cell nuclei by four potential nuclear localization signals. Nuclear MYH9 bound to the CTNNB1 promoter through its DNA-binding domain, and interacted with myosin light chain 9, ß-actin and RNA polymerase II to promote CTNNB1 transcription, which conferred resistance to anoikis in GC cells in vitro and in vivo. Staurosporine reduced nuclear MYH9 S1943 phosphorylation to inhibit CTNNB1 transcription, Wnt/ß-catenin signaling activation and GC progression in both orthotropic xenograft GC nude mouse and transgenic GC mouse models. Conclusion: This study identified that nuclear MYH9-induced CTNNB1 expression promotes GC metastasis, which could be inhibited by staurosporine, indicating a novel therapy for GC peritoneal metastasis.

[Association between serotonin transporter promoter gene polymorphism and clinicopathological factors and effect of the polymorphism on the prognosis of colorectal cancer patients].

OBJECTIVE: To examine the association between the genotype (LL, LS and SS) of serotonin transporter promoter gene polymorphism(5-HTTLPR) and clinicopathological factors, and to investigate the effect of 5-HTTLPR on the prognosis of colorectal cancer patients. METHODS: Data of peripheral blood samples of 161 colorectal cancer patients at the Second Affiliated Hospital of Guangzhou Medical University from October 2009 to January 2014 were collected retrospectively. The genotyping of 5-HTTLPR was determined by PCR and agarose gel electrophoresis. Coincidence Chi-square test was used to examine the 5-HTTLPR genotype with Hardy-Weinberg law. Chi-square test and Cox multifactor model were used to analyze the association of 5-HTTLPR genotype with clinicopathology and prognosis. All the patients were informed and agreed to participate in the study. This study was approved by the Hospital Ethics Committee (2015056). RESULTS: Of 161 colorectal cancer patients, 89 were male and 72 were female; the median age was 64 (25-85) years; 86 (53.5%) cases were colon cancer and 75 (46.5%) were rectal cancer. Genotype was LL in 12 cases, LS in 59 cases and SS in 90 cases, which complied with the law of Hardy-Weinberg genetic balance (χ²=0.288, P=0.592). Univariate analysis showed that 5-HTTLPR gene polymorphism was only associated with lymph node metastasis [lymph node metastasis rate: LL and LS genotype 21.1% (15/71);SS genotype 40.0% (36/90), χ²= 6.532, P=0.011]. The 3-year and 5-year overall survival rates of whole patients were 71% and 63% respectively. Multivariate analysis revealed that the SS genotype was an independent risk factor affecting the overall survival of colorectal cancer patients(HR=1.933, 95%CI:1.090-3.428, P=0.024). CONCLUSION: Among genotypes of 5-HTTLPR gene, colorectal cancer patients with SS genotype have higher risk of lymph node metastasis and poorer prognosis.

Dihydromyricetin-mediated inhibition of the Notch1 pathway induces apoptosis in QGY7701 and HepG2 hepatoma cells.

AIM: To investigate whether Dihydromyricetin (DHM) inhibits cell proliferation and promotes apoptosis by downregulating Notch1 expression. METHODS: The correlation between Notch1 and Hes1 (a Notch1 target molecule) expression in hepatoma samples was confirmed by qRT-PCR. In addition, MTT assays, flow cytometry and TUNEL analysis showed that DHM possessed strong anti-tumor properties, evidenced not only by reduced cell proliferation but also by enhanced apoptosis in QGY7701 and HepG2 hepatocellular carcinoma (HCC) cells. The expressions of Notch1, Hes1, Bcl-2 and Bax were determined by Western blot. RESULTS: Among the tested samples (n = 64), the expression levels of Notch1 (75% of patients) and Hes1 (79.7% of patients) mRNA in tumor tissues were higher than in the normal liver tissues. There was a negative correlation between the expression of Notch1 and the degree of differentiation and positively correlated with the Alpha Fetal Protein concentration. The viability of HCC cells treated with DHM was significantly inhibited in a dose and time-dependent manner. Apoptosis was induced in HepG2 and QGY7701 cell lines following 24 h of DHM treatment. After treatment with DHM, the protein expression of Notch1 was downregulated, the apoptosis-related protein Bax was upregulated and Bcl2 was downregulated. Notch1 siRNA further enhanced the anti-tumor properties of DHM. CONCLUSION: Notch1 is involved in the development of HCC and DHM inhibits cell proliferation and promotes apoptosis by down-regulating the expression of Notch1.

Crystal Violet and XTT Assays on Staphylococcus aureus Biofilm Quantification.

Staphylococcus aureus (S. Aureus) is a common food-borne pathogenic microorganism. Biofilm formation remains the major obstruction for bacterial elimination. The study aims at providing a basis for determining S. aureus biofilm formation. 257 clinical samples of S. aureus isolates were identified by routine analysis and multiplex PCR detection and found to contain 227 MRSA, 16 MSSA, 11 MRCNS, and 3 MSCNS strains. Two assays for quantification of S. aureus biofilm formation, the crystal violet (CV) assay and the XTT (tetrazolium salt reduction) assay, were optimized, evaluated, and further compared. In CV assay, most isolates formed weak biofilm 74.3 %), while the rest formed moderate biofilm (23.3 %) or strong biofilm (2.3 %). However, most isolates in XTT assay showed weak metabolic activity (77.0 %), while the rest showed moderate metabolic activity (17.9 %) or high metabolic activity (5.1 %). In this study, we found a distinct strain-to-strain dissimilarity in terms of both biomass formation and metabolic activity, and it was concluded from this study that two assays were mutual complementation rather than being comparison.