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The chemoresistance and toxicity of traditional chemotherapeutic drugs have become obstacles to their antitumor effects in ovarian cancers. Therefore, it is particularly important to develop new anticancer drugs to increase target sensitivity and reduce the toxicity of chemotherapy drugs. As key organelles, the endoplasmic reticulum and mitochondria play important role in chemoresistance. Cells become resistant to drugs by maintaining the homeostasis of the endoplasmic reticulum and mitochondria. Chaetomugilin J, a metabolite isolated from Polygonatum sibiricum, belongs to the Chaetomium family and exhibits potent cytotoxicity. In this study, we aimed to explore the mechanistic link between apoptosis and endoplasmic reticulum stress, mitophagy and mitochondrial dysfunction induced by chaetomugilin J combined with cisplatin in the ovarian cancer cell line A2780. Methods: Chaetomugilin J was identified by chemical methods. Cell viability was measured by an MTT assay. The apoptosis, mitochondrial membrane potential, and intracellular reactive oxygen species (ROS) were examined by flow cytometry. Mitochondrial ROS was measured by a fluorescence microscope with MitoSox staining. Further, the related proteins and overexpression of parkin were detected by Western blot. Results: Chaetomugilin J combined with low-dose cisplatin decreased cell viability and increased apoptosis in A2780 cells. In addition, intracellular ROS and mitochondrial ROS were increased, while the mitochondrial membrane potential was reduced. The expressions of grp78 and chop were decreased after treatment by chaetomugilin J combined with lowdose cisplatin. Overexpression of parkin attenuated chaetomugilin J combined with cisplatininduced apoptosis. Conclusion: Chaetomugilin J combined with cisplatin inhibited pink1/parkin mediated mitophagy increased mitochondrial dysfunction in the A2780 cells and enhanced apoptosis induced by cisplatin in the ovarian cancer cell line A2780. But this process was not related to endoplasmic reticulum apoptotic pathway.

Background and Aim The biological characterization of microbial environment in early gastric cancer (EGC), other than Helicobacter pylori, is limited. This study aimed to explore the microbial microenvironment in chronic gastritis (CG), fundic gland polyps (FGPs), low‐grade intraepithelial neoplasia (LGIN), and EGC. Methods 16S‐rRNA gene sequencing and bioinformatic analysis were performed on 63 individuals with 252 mucosal biopsies or endoscopic submucosal dissection margin samples from endoscopy. Results The microbiota in gastric LGIN functions analogously to EGC in terms of functional prediction. Neoplastic lesions showed a significant difference to CG or FGPs in beta diversity of the microbiota. Bacteria genera including Paracoccus, Blautia, Barnesiella, Lactobacillus, Thauera, Collinsella were significantly enriched in gastric neoplastic mucosa (LGIN and EGC) compared with non‐neoplastic tissues (CG and FGPs). While Pseudomonas and Kingella were depleted in neoplastic tissues. FGPs showed a distinctive microbial network system that negatively interacted with Helicobacter. Conclusions In terms of the mucosal microbial microenvironment, gastric LGIN and EGC showed no significant difference as early neoplastic lesions. We observed a coordinated microbial microenvironment that correlated negatively with Helicobacter.

Background: The effect of ginsenosides on the growth and apoptosis of human lens epithelial (HLE) B3 cells exposed to H 2 O 2 was investigated. In addition, the effect of ginsenosides on gene expression in HLE-B3 cells was analyzed using microarray assays to determine its molecular mechanism. Methods: HLE-B3 cells were treated with 1.75 M H 2 O 2 in the presence or absence of 5, 10 or 20 μM ginsenosides. Cell viability and apoptosis were examined by MTT assays and flow cytometry, respectively, at 24 to 120 h after the treatment. Furthermore, HLE-B3 cells were treated with 20 μM ginsenosides for 8 days and total RNA was isolated and analyzed using the Affymetrix GeneChip Array. Principal component analysis was performed to visualize the microarray data. Results: Addition of ginsenosides significantly alleviated the growth inhibitory effect of H 2 O 2 on HLE-B3 cells and the percentage of viable cells was increased by more than 3 folds. Flow cytometric analysis showed that 6.16 ± 0.29% of H 2 O 2 -treated HLE-B3 cells were early apoptotic cells, and the percentage was reduced to 4.78 ± 0.16% (P < 0.05) in the presence of 20 μM ginsenosides. Principal component analysis revealed that ginsenoside caused extensive changes in gene expression in HLE-B3 cells. A total of 6219 genes showed significant differential expression in HLE-B3 cells treated with ginsenoside; among them, 2552 (41.0%) genes were significantly upregulated, whereas 3667 (59.0%) genes were significantly downregulated. FOXN2, APP and RAD23B were the top three upregulated genes while WSB1, PSME4 and DCAF7 were the top three downregulated genes in HLE-B3 cells treated with ginsenosides. Conclusion: Ginsenosides induce extensive changes in the expression of genes involved in multiple signaling pathways, including apoptotic signaling pathway and DNA damage response signaling pathway. Ginsenosides alleviate H 2 O 2 -induced suppression of the growth of HLB cells and inhibit H 2 O 2 -induced apoptosis of HLB cells.

Drug resistance remains a challenge in ovarian cancer. In addition to aberrant activation of relevant signaling pathways, the adaptive stress response is emerging as a new spotlight of drug resistance in cancer cells. Stress granules (SGs) are one of the most important features of the adaptive stress response, and there is increasing evidence that SGs promote drug resistance in cancer cells. In the present study, we compared two types of ovarian cancer cells, A2780 and SKOV3, using the dual PI3K/mTOR inhibitor, PKI-402. We found that SGs were formed and SGs could intercept the signaling factor ATF5 and regulate the response of mitochondrial unfolded protein(mtUPR)in A2780 cells. Therefore, exploring the network formed between SGs and membrane-bound organelles, such as mitochondria, may provide new insight into the mechanisms of action of antitumor drugs.

Drug resistance remains a challenge in ovarian cancer. In addition to aberrant activation of relevant signaling pathways, the adaptive stress response is emerging as a new spotlight of drug resistance in cancer cells. Stress granules (SGs) are one of the most important features of the adaptive stress response, and there is increasing evidence that SGs promote drug resistance in cancer cells. In the present study, we compared two types of ovarian cancer cells, A2780 and SKOV3, using the dual PI3K/mTOR inhibitor, PKI-402. We found that SGs were formed and SGs could intercept the signaling factor ATF5 and regulate the response of mitochondrial unfolded protein(mtUPR)in A2780 cells. Therefore, exploring the network formed between SGs and membrane-bound organelles, such as mitochondria, may provide new insight into the mechanisms of action of antitumor drugs.

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