New potential chemotherapy for ovarian cancer - Combined therapy with WP 631 and epothilone B

Investigation of the cytotoxicity induced by cannabinoids on human ovarian carcinoma cells

Cannabinoids have been shown to induce anti-tumor activity in a variety of carcinoma cells such as breast, prostate, and brain. The aim of the present study is to investigate the anti-tumor activity of cannabinoids, CBD (cannbidiol), and CBG (cannabigerol) in ovarian carcinoma cells sensitive and resistant to chemotherapeutic drugs. Sensitive A2780 cells and resistant A2780/CP70 carcinoma cells and non-carcinoma cells were exposed to varying concentrations of CBD, CBG, carboplatin or CB1 and CB2 receptor antagonists, AM251 and AM630, respectively, alone or in combination, at different exposure times and cytotoxicity was measured by MTT assay. The mechanism of action of CBD and CB in inducing cytotoxicity was investigated involving a variety of apoptotic and cell cycle assays. Treatment with CBD and CBG selectively, dose and time dependently reduced cell viability and induced apoptosis. The effect of CBD was stronger than CBG in all cell lines tested. Both CBD and CBG induced stronger cytotoxicity than afforded by carboplatin in resistant cells. The cytotoxicity induced by CBD was not CB1 or CB2 receptor dependent in both carcinoma cells, however, CBG-induced cytotoxicity may involve CB1 receptor activity in cisplatin-resistant carcinoma cells. A synergistic effect was observed when cannabinoids at sublethal doses were combined with carboplatin in both carcinoma cells. The apoptotic event may involve loss of mitochondrial membrane potential, Annexin V, caspase 3/7, ROS activities, and cell cycle arrest. Further studies are required to investigate whether these results are translatable in the clinic. Combination therapies with conventional cancer treatments using cannabinoids are suggested.

Cytoplasmic SIRT1 promotes paclitaxel resistance in ovarian carcinoma through increased formation and survival of polyploid giant cancer cells

Therapeutic resistance is a notable cause of death in patients with ovarian carcinoma. Polyploid giant cancer cells (PGCCs), commonly arising in tumor tissues following chemotherapy, have recently been considered to contribute to drug resistance. As a type III deacetylase, Sirtuin1 (SIRT1) plays essential roles in the cell cycle, cellular senescence, and drug resistance. Accumulating evidence has suggested that alteration in its subcellular localization via nucleocytoplasmic shuttling is a critical process influencing the functions of SIRT1. However, the roles of SIRT1 subcellular localization in PGCC formation and subsequent senescence escape remain unclear. In this study, we compared the differences in the polyploid cell population and senescence state of PGCCs following paclitaxel treatment between tumor cells overexpressing wild-type SIRT1 (WT SIRT1) and those expressing nuclear localization sequence (NLS)-mutated SIRT1 (SIRT1NLSmt ). We investigated the involvement of cytoplasmic SIRT1 in biological processes and signaling pathways, including the cell cycle and cellular senescence, in ovarian carcinoma cells' response to paclitaxel treatment. We found that the SIRT1NLSmt tumor cell population contained more polyploid cells and fewer senescent PGCCs than the SIRT1-overexpressing tumor cell population. Comparative proteomic analyses using co-immunoprecipitation (Co-IP) combined with liquid chromatography-mass spectrometry (LC-MS)/MS showed the differences in the differentially expressed proteins related to PGCC formation, cell growth, and death, including CDK1 and CDK2, between SIRT1NLSmt and SIRT1 cells or PGCCs. Our results suggested that ovarian carcinoma cells utilize polyploidy formation as a survival mechanism during exposure to paclitaxel-based treatment via the effect of cytoplasmic SIRT1 on PGCC formation and survival, thereby boosting paclitaxel resistance. © 2023 The Pathological Society of Great Britain and Ireland.

Ferroptosis-Related Gene Signature Promotes Ovarian Cancer by Influencing Immune Infiltration and Invasion

Ovarian cancer is a kind of gynecological malignancy with high mortality. Ferroptosis is a new type of iron-dependent cell death characterized by the formation of lipid peroxides and excessive accumulation of reactive oxygen species. Studies have shown that ferroptosis modulates tumor genesis, progression, and invasion, including ovarian cancer. Based on the mRNA expression data from TCGA, we construct a scoring system using consensus clustering analysis, univariate Cox regression analysis, and least absolute selection operator. Then, we systematically evaluate the relationship between score and clinical characteristics of ovarian cancer. The result from the prediction of biofunction pathways shows that score serves as an independent prognostic marker for ovarian cancer and affects tumor progression by modulating tumor metastasis. Moreover, immunocytes such as activated CD4 T cell, activated CD8 T cell, regulatory T cells, macrophage, and stromal cells, including adipocytes, epithelial cells, and fibroblast infiltrate more in the tumor microenvironment in a high-score group, indicating ferroptosis can also affect tumor immune landscape. Critically, four potentially sensitive drugs, including staurosporine, epothilone B, DMOG, and HG6-64-1 based on the scores, are predicted, and DMOG is recognized as a novel targeted drug for ovarian cancer. In general, we construct the scoring system based on ferroptosis-related genes that can predict the prognosis of ovarian cancer patients and propose that ferroptosis may affect ovarian cancer progression by mediating tumor metastasis and immune landscape. Novel drugs to target ovarian cancer are also predicted.

Differential Characteristics of HMGB2 Versus HMGB1 and their Perspectives in Ovary and Prostate Cancer

We have summarized common and differential functions of HMGB1 and HMGB2 proteins with reference to pathological processes, with a special focus on cancer. Currently, several "omic" approaches help us compare the relative expression of these 2 proteins in healthy and cancerous human specimens, as well as in a wide range of cancer-derived cell lines, or in fetal versus adult cells. Molecules that interfere with HMGB1 functions, though through different mechanisms, have been extensively tested as therapeutic agents in animal models in recent years, and their effects are summarized. The review concludes with a discussion on the perspectives of HMGB molecules as targets in prostate and ovarian cancers.

Effects of Shen Cao Granules on Chemotherapy-Induced Thrombocytopenia in Gastrointestinal Cancer Patients: A Randomized Controlled Trial

Background: To observe clinical effects of Shen Cao granules on thrombocytopenia in patients with gastrointestinal cancer undergoing chemotherapy. Patients and Methods: Patients under a FOLFIRI chemotherapy regimen (n = 92) were randomly divided into study and control groups (n = 46 for each group) and were given 10 g of Shen Cao granules and a placebo, respectively, once daily on chemotherapy treatment days. Platelet counts were measured every other day and any adverse reaction recorded during the study and at follow-up. Results: The incidence of thrombocytopenia (grades II-IV) in the study group was significantly decreased, and the length of hospitalization significantly reduced compared with the control group (11.21 ± 2.46 vs 15.34 ± 3.68 days, P < .05). The minimum numbers of post-chemotherapy platelets and the values of platelet counts 21 days after chemotherapy were significantly increased ([100.65 ± 63.16] × 10⁹/L vs [60.21 ±37.22] × 10⁹/L, P < .05; [267.81 ± 81.32] × 10⁹/L vs [146.42 ± 70.54] × 10⁹/L, P < .001), and the duration of thrombocytopenia and treatment with recombinant human interleukin-11 was significantly decreased in the Shen Cao treatment compared with the control group. No serious adverse events were observed. Conclusions: Shen Cao granules were effective in decreasing chemotherapy-induced thrombocytopenia, shortened the duration of thrombocytopenia, and reduced the length of hospital stay and costs.

Gemcitabine-loaded RGD modified liposome for ovarian cancer: preparation, characterization and pharmacodynamic studies

Background

Ovarian cancer is the third leading cause of death among gynecological cancers in women in China. Chemotherapy is an important method for comprehensive treatment of ovarian cancer, but the curative effect is poor.

Purpose

In this study, gemcitabine (GEM) -loaded RGD modified liposomes (LPs) were developed by the emulsification-solvent evaporation method and evaluated for their antitumor activity in vitro and in vivo.

Methods

The physicochemical properties of LPs such as particle size, zeta potential and in vitro drug release were investigated. We also demonstrated the effect of RGD-GEM-PEG LPs in ovarian cancer.

Results

RGD-PEG3500-DSPE GEM LPs had a uniform spherical morphology. The mean particle size and polydispersity index were determined to be 106.7 nm and 0.13 respectively. The ER% and DL% of the formulation were 79.6±3.1% and 6.1±1.4% respectively. Compared with the free drug, RGD modified GEM LPs had sustained-release properties in vitro. In vivo, compared with the DiD-RGD-PEG3500-DSPE GEM LPs group, free DiD-GEM and DiD-GEM LPs had no obvious fluorescence intensity in tumor of mice at all times, indicating that ordinary liposomes and drugs had no tumor targeting function. RGD-PEG3500-DSPE GEM LPs showed a superior antiproliferative effect on SKOV3 cells and had a better antitumor effect in vivo than non-modified LPs.

Conclusion

These results indicated that RGD-PEG3500-DSPE GEM LPs were a promising candidate for antitumor drug delivery.

Docosahexaenoic acid and disulfiram act in concert to kill cancer cells: a mutual enhancement of their anticancer actions

We previously reported a synergistic anticancer action of clioquinol and docosahexaenoic acid (DHA) in human cancer cells. However, clioquinol has been banned from the clinic due to its neurotoxicity. This study identified disulfiram (DSF) as a substitute compound to clioquinol, acting in concert with DHA to more effectively kill cancer cells and suppress tumor growth. Treatment with DSF and DHA induced greater apoptotic cell death and suppression of tumor growth in vitro and in vivo, as compared to DSF and DHA used alone. Mechanistic studies demonstrated that DSF enhances DHA-induced cellular oxidative stress as evidenced by up-regulation of Nrf2-mediated heme oxygenase 1 (HO-1) gene transcription. On the other hand, DHA was found to enhance DSF-induced suppression of mammosphere formation and stem cell frequency in a selected cancer model system, indicating that alterations to cancer cell stemness are involved in the combinatory anticancer action of DSF and DHA. Thus, DHA and DSF, both clinically approved drugs, act in concert to more effectively kill cancer cells. This combinatory action involves an enhancement of cellular oxidative stress and suppression of cancer cell stemness.

Suppressive Role of MicroRNA-148a in Cell Proliferation and Invasion in Ovarian Cancer Through Targeting Transforming Growth Factor-β-Induced 2

Ovarian cancer (OC) is one of the most common gynecological malignancies. MicroRNAs (miRs) play a crucial role in the development and progression of OC, but the underlying mechanism remains largely unclear. Our study investigated the regulatory role of miR-148a in OC cell proliferation and invasion. We found that miR-148a was significantly downregulated in OC tissues compared to their matched adjacent nontumor tissues. In addition, its expression was also reduced in OC cell lines (SKOV3, ES-2, OVCAR, and A2780) compared to normal ovarian epithelial cells. Overexpression of miR-148a caused a significant decrease in OC cell proliferation and invasion, as well as reduced MMP9 protein levels. Transforming growth factor-β-induced 2 (TGFI2) was further identified as a target gene of miR-148a, and its protein expression was downregulated in OC cells after miR-148a overexpression. Restoration of TGFI2 attenuated the suppressive effects of miR-148a on OC cell proliferation and invasion. Moreover, we found that TGFI2 was remarkably upregulated in OC tissues when compared with their matched adjacent nontumor tissues, and observed a reverse correlation between miR-148a and TGFI2 expression in OC tissues. On the basis of these findings, we suggest that miR-148a inhibits OC cell proliferation and invasion partly through inhibition of TGFI2. Therefore, our study highlights the importance of the miR-148a/TGFI2 axis in the malignant progression of OC.