HER2 decreases drug sensitivity of ovarian cancer cells via inducing stem cell-like property in an NFκB-dependent way

Novel Approaches for the Solid-Phase Synthesis of Dihydroquinazoline-2(1H)-One Derivatives and Biological Evaluation as Potential Anticancer Agents

In the design of antineoplastic drugs, quinazolinone derivatives are often used as small molecule inhibitors for kinases or receptor kinases, such as the EGFR tyrosine kinase inhibitor gefitinib, p38MAP kinase inhibitor DQO-501, and BRD4 protein inhibitor PFI-1. A novel and convenient approach for the solid-phase synthesis of dihydroquinazoline-2(1H)-one derivatives was proposed and 19 different compounds were synthesized. Cytotoxicity tests showed that most of the target compounds had anti-proliferative activity against HepG-2, A2780 and MDA-MB-231 cell lines. Among them, compounds CA1-e and CA1-g had the most potent effect on A2780 cells, with IC₅₀ values of 22.76 and 22.94 μM, respectively. In addition, in an antioxidant assay, the IC₅₀ of CA1-7 was 57.99 μM. According to bioinformatics prediction, ERBB2, SRC, TNF receptor, and AKT1 were predicted to be the key targets and play an essential role in cancer treatment. ADMET prediction suggested 14 of the 19 compounds had good pharmacological properties, i.e., these compounds displayed clinical potential. The correct structure of the final compounds was confirmed based on LC/MS, ¹H NMR, and ¹³C NMR.

Network Pharmacology, Integrated Bioinformatics, and Molecular Docking Reveals the Anti-Ovarian Cancer Molecular Mechanisms of Cinnamon (Cinnamomum cassia (L.) J. Presl)

Cinnamon ( Cinnamomum cassia (L.) J. Presl) is a popular natural spice with various pharmacological properties. This study was based on network pharmacology integrating bioinformatics and molecular docking to explore the potential molecular mechanisms of cinnamon in the treatment of ovarian cancer (OC). The chemical composition of cinnamon was collected from the TCMSP database to predict its targets and construct a “cinnamon active component target” network. OC-related genes were retrieved from Genecards and DisGeNET databases. The “disease-target” network was established, and the drug targets were mapped to the disease targets, and the key targets obtained from the mapping were subjected to DAVID analysis to construct a “component-target-pathway” network diagram. The active ingredients of cinnamon were molecularly docked to the core targets to predict the molecular mechanism of cinnamon in the treatment of ovarian cancer. From cinnamon, 105 chemical components were screened and de-duplicated to obtain 15 active components and 74 drug target proteins, and 26 common targets were obtained after mapping drug targets to disease targets. 368 entries were identified by GO enrichment analysis, mainly including biological progresses such as regulation of smooth muscle contraction and regulation of tube diameter, and molecular functions such as antioxidant activity, and peroxidase activity. The KEGG pathway enrichment analysis identified 4 signaling pathways, neuroactive ligand-receptor interaction, HIF-1 signaling pathway, regulation of lipolysis in adipocytes, and complement and coagulation cascades. Molecular docking analysis showed good affinity of these key targets with representative components of OC. There was a stable interaction between DIBP and ADRB2 and NR3C1. There is a stable interaction between oleic acid and C2K, EDN1, ERBB2, PLAU, PLG, PRSS3, PTGS1, PTGS2, SERPINE1 and SLC2A1. Cinnamon exerted its therapeutic effects on OC through multiple pathways and targets.

HNMT Upregulation Induces Cancer Stem Cell Formation and Confers Protection against Oxidative Stress through Interaction with HER2 in Non-Small-Cell Lung Cancer

Background: The treatment of non-small-cell lung cancer (NSCLC) involves platinum-based chemotherapy. It is typically accompanied by chemoresistance resulting from antioxidant properties conferred by cancer stem cells (CSCs). Human epidermal growth factor receptor 2 (HER2) enhances CSCs and antioxidant properties in cancers, including NSCLC. Methods: Here, we elucidated the role of histamine N-methyltransferase (HNMT), a histamine metabolism enzyme significantly upregulated in NSCLC and coexpressed with HER2. HNMT expression in lung cancer tissues was determined using quantitative reverse transcription PCR (RT-qPCR). A publicly available dataset was used to determine HNMT’s potential as an NSCLC target molecule. Immunohistochemistry and coimmunoprecipitation were used to determine HNMT–HER2 correlations and interactions, respectively. HNMT shRNA and overexpression plasmids were used to explore HNMT functions in vitro and in vivo. We also examined miRNAs that may target HNMT and investigated HNMT/HER2’s role on NSCLC cells’ antioxidant properties. Finally, how HNMT loss affects NSCLC cells’ sensitivity to cisplatin was investigated. Results: HNMT was significantly upregulated in human NSCLC tissues, conferred a worse prognosis, and was coexpressed with HER2. HNMT depletion and overexpression respectively decreased and increased cell proliferation, colony formation, tumorsphere formation, and CSCs marker expression. Coimmunoprecipitation analysis indicated that HNMT directly interacts with HER2. TARGETSCAN analysis revealed that HNMT is a miR-223 and miR-3065-5p target. TBHp treatment increased HER2 expression, whereas shHNMT disrupted the Nuclear factor erythroid 2-related factor 2 (Nrf2)/ hemeoxygenase-1 (HO-1)/HER2 axis and increased reactive oxygen species accumulation in NSCLC cells. Finally, shHNMT sensitized H441 cells to cisplatin treatment in vitro and in vivo. Conclusions: Therefore, HNMT upregulation in NSCLC cells may upregulate HER2 expression, increasing tumorigenicity and chemoresistance through CSCs maintenance and antioxidant properties. This newly discovered regulatory axis may aid in retarding NSCLC progression and chemoresistance.

Emodin exerts antitumor effects in ovarian cancer cell lines by preventing the development of cancer stem cells via epithelial mesenchymal transition

Ovarian cancer has the worst prognosis among all types of gynecological malignancies and patients are often diagnosed at an advanced stage with distant metastasis. In the present study, it was found that emodin, a small molecular chemical drug derived from natural plants, has antitumor effects on ovarian cancer cells. Emodin induced cytotoxicity and inhibited proliferation in the ovarian cancer cell lines, SK-OV-3, A2780 and PA-1. In addition, emodin inhibited the migration and invasion abilities of the ovarian cancer cells by inhibiting epithelial-mesenchymal transition (EMT), which was evidenced by the downregulation of N-cadherin and vimentin, and the upregulation of E-cadherin protein expression levels. When a subcutaneous xenograft SK-OV-3 tumor mouse model was used, emodin notably reduced the tumor growth rate and inhibited tumor cell proliferation. Furthermore, mechanical analysis revealed that emodin markedly inhibited EMT and reduced the stemness of tumor cells, which was evidenced by the decrease in the protein expression of CD133 and Oct4. Pulmonary metastasis of the ovarian cancer cells was significantly suppressed in the tumor mouse model by the administration of emodin. In addition, flow cytometry analysis indicated that emodin significantly reduced the proportion of ovarian cancer stem-like cells in metastatic lung tissues. In conclusion, emodin, a potent inhibitor of EMT, could serve as a potential candidate for ovarian cancer therapy.

The role of the MAD2-TLR4-MyD88 axis in paclitaxel resistance in ovarian cancer

Despite the use of front-line anticancer drugs such as paclitaxel for ovarian cancer treatment, mortality rates have remained almost unchanged for the past three decades and the majority of patients will develop recurrent chemoresistant disease which remains largely untreatable. Overcoming chemoresistance or preventing its onset in the first instance remains one of the major challenges for ovarian cancer research. In this study, we demonstrate a key link between senescence and inflammation and how this complex network involving the biomarkers MAD2, TLR4 and MyD88 drives paclitaxel resistance in ovarian cancer. This was investigated using siRNA knockdown of MAD2, TLR4 and MyD88 in two ovarian cancer cell lines, A2780 and SKOV-3 cells and overexpression of MyD88 in A2780 cells. Interestingly, siRNA knockdown of MAD2 led to a significant increase in TLR4 gene expression, this was coupled with the development of a highly paclitaxel-resistant cell phenotype. Additionally, siRNA knockdown of MAD2 or TLR4 in the serous ovarian cell model OVCAR-3 resulted in a significant increase in TLR4 or MAD2 expression respectively. Microarray analysis of SKOV-3 cells following knockdown of TLR4 or MAD2 highlighted a number of significantly altered biological processes including EMT, complement, coagulation, proliferation and survival, ECM remodelling, olfactory receptor signalling, ErbB signalling, DNA packaging, Insulin-like growth factor signalling, ion transport and alteration of components of the cytoskeleton. Cross comparison of the microarray data sets identified 7 overlapping genes including MMP13, ACTBL2, AMTN, PLXDC2, LYZL1, CCBE1 and CKS2. These results demonstrate an important link between these biomarkers, which to our knowledge has never before been shown in ovarian cancer. In the future, we hope that triaging patients into alterative treatment groups based on the expression of these three biomarkers or therapeutic targeting of the mechanisms they are involved in will lead to improvements in patient outcome and prevent the development of chemoresistance.

Tetrandrine Reverses Paclitaxel Resistance in Human Ovarian Cancer via Inducing Apoptosis, Cell Cycle Arrest Through β-Catenin Pathway

Background

Paclitaxel (PTX) resistance is a great obstacle for the treatment of ovarian cancer. A previous study indicated that tetrandrine (TET) could induce the apoptosis of ovarian cancer cells. This study aimed to explore the effect of TET in combination with PTX on PTX resistance in ovarian cancer cells.

Materials and Methods

CCK-8 assay, flow cytometry and wound healing assays were used to detect the proliferation, apoptosis and migration of PTX-resistant SKOV3 cells (SKOV3/PTX). The expressions of Bax, Bcl-2, cleaved caspase 3, β-catenin, c-Myc, cyclin D1 and p21 in SKOV3/PTX cells were detected with Western blot. In vivo animal study was performed finally.

Results

In this study, the inhibitory effects of PTX on the proliferation and migration of SKOV3/PTX cells were markedly enhanced by TET. In addition, PTX-induced apoptosis in SKOV3/PTX cells was significantly enhanced by the treatment of TET via upregulating the levels of Bax and cleaved caspase 3, and downregulating the expression of Bcl-2. Moreover, combination of TET and PTX obviously induced cell cycle arrest in SKOV3/PTX cells via increasing the level of p21 and decreasing the levels of c-Myc and Cyclin D1. Meanwhile, combination of TET with PTX significantly decreased the expression of β-catenin in SKOV3/PTX cells. In vivo experiments further confirmed that TET enhanced the anti-tumor effect of PTX in SKOV3/PTX xenograft model.

Conclusion

We found that TET could enhance the sensitivity of SKOV3/PTX cells to PTX via inhibiting the β-catenin/c-Myc/Cyclin D1 signaling pathway. Therefore, PTX combined with TET might be considered as a potential approach for the treatment of PTX-resistant ovarian cancer.