Capparis zeylanica L. root extract promotes apoptosis and cell cycle arrest, inhibits epithelial-to-mesenchymal transition and triggers E-cadherin expression in breast cancer cell lines

Uvaol attenuates TGF-β1-induced epithelial-mesenchymal transition in human alveolar epithelial cells by modulating expression and membrane localization of β-catenin

The epithelial-mesenchymal transition (EMT) is a biological process in which epithelial cells change into mesenchymal cells with fibroblast-like characteristics. EMT plays a crucial role in the progression of fibrosis. Classical inducers associated with the maintenance of EMT, such as TGF-β1, have become targets of several anti-EMT therapeutic strategies. Natural products from the pentacyclic triterpene class have emerged as promising elements in inhibiting EMT. Uvaol is a pentacyclic triterpene found in olive trees (Olea europaea L.) known for its anti-inflammatory, antioxidant, and antiproliferative properties. Yet, its effect on the TGF-β1-induced EMT in alveolar epithelial cells is unknown. The present study aimed to investigate the impact of uvaol upon TGF-β1-induced EMT in a cultured A549 human alveolar epithelial cell line, a classic in vitro model for studies of EMT. Changes in cell shape were measured using phase-contrast and confocal microscopy, whereas protein expression levels were measured using immunofluorescence, flow cytometry, and Western blotting. We also performed wound scratch experiments to explore its effects on cell migration. Uvaol had no significant cytotoxic effects on A549 cells. By contrast, the changes in the cell morphology consistent with TGF-β1-induced EMT were largely suppressed by treatment with uvaol. In addition, increased contents of mesenchymal markers, namely, vimentin, N-cadherin, and fibronectin in TGF-β1-induced A549 cells, were downregulated by uvaol treatment. Furthermore, the TGF-β1-induced migration of A549 cells was significantly suppressed by uvaol. Mechanistically, uvaol prevented the nuclear translocation of β-catenin and reduced the TGF-β1-induced levels of ZEB1 in A549 cells. These results provide compelling evidence that uvaol inhibits EMT by regulating proteins related to the mesenchymal profile in human alveolar epithelial cells, likely by modulating β-catenin and ZEB1 levels.

Novel sulfamethoxazole and 1-(2-fluorophenyl) piperazine derivatives as potential apoptotic and antiproliferative agents by inhibition of BCL2; design, synthesis, biological evaluation, and docking studies

In the present study, a novel series of sulfamethoxazole and 1-(2-fluorophenyl) piperazine derivatives were designed, synthesized and characterized by FTIR, IH NMR,13C NMR, Mass spectrometry, CHN data, and evaluated for their efficiency as BCL2 inhibitors that could lead to potential antiproliferative activity. The ten newly synthesized compounds were screened for their therapeutic activity using MDA-MB-231 breast cancer cell lines. All the test compounds exhibited moderate to high cytotoxic activity in MTT assay. Among them, compounds 3e and 6b exhibited promising antitumor activity, as evidenced by their IC50 values of 16.98 and 17.33 μM respectively. In addition, both compounds 3e and 6b displayed potential antioxidant and apoptosis induction properties. The qRT-PCR analysis showed down regulation of BCL2 expression and up regulation of Casp3 expression in 3e and 6b treated MDA-MB-231 cells. Further, the interaction between critical amino acids of the active domains of BCL2 and 3e and 6b was evaluated by MD simulation, and the results reflected the potent inhibitory activities of 3e and 6b. In summary, the novel compounds 3e and 6b demonstrate their potent anti-cancer properties by inducing apoptosis and selectively targeting BCL2 and caspases-3.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-024-04111-6.

Aptamer functionalized hypoxia-potentiating agent and hypoxia-inducible factor inhibitor combined with hypoxia-activated prodrug for enhanced tumor therapy

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer. Hypoxia-activated prodrugs (HAPs) have shown promise as potential therapeutic agents for TNBC. While increasing hypoxia levels may promote the HAP activation, it raises concerns regarding HIF1α-dependent drug resistance. It is desirable to develop a targeted approach that enhances tumor hypoxia for HAP activation without promoting HIF1α-dependent drug resistance in TNBC treatment. Herein, we proposed a multi-responsive carrier-free self-assembled nanomedicine named AQ4N@CA4T1ASO. This nanomedicine first targeted tumors by the TNBC-targeting aptamers (T1), and then disassembled in the reductive and acidic conditions within tumors. The released Combretastatin 4 (CA4) could exacerbate hypoxia, thereby promoting the conversion of inactive Banoxantrone (AQ4N) to its active form, AQ4. Simultaneously, the released antisense oligonucleotide (ASO) could attenuate hypoxia-induced HIF1α mRNA expression, thereby sensitizing the tumor to chemotherapy. Overall, this smart nanomedicine represents a profound targeted therapy strategy, combining "hypoxia-potentiating, hypoxia-activated, chemo-sensitization" approaches for TNBC treatment. In vivo study demonstrated significant suppression of tumor growth, highlighting the promising potential of this nanomedicine for future clinical translation.

Ursolic acid regulates key EMT transcription factors, induces cell cycle arrest and apoptosis in MDA-MB-231 and MCF-7 breast cancer cells, an in-vitro and in silico studies

Epithelial-mesenchymal transition (EMT) is a vital process in tumorigenesis and metastasis of breast cancer. In our quest to explore effective anticancer alternatives, ursolic acid (UA) was purified from Capparis zeylanica and investigated for its anticancer activity against MDA-MB-231 and MCF-7 breast cancer cells. The apparent anticancer activity of UA on MDA-MB-231 and MCF-7 cells was evident from IC50 values of 14.98 and 15.99 μg/mL, respectively, in MTT assay and also through enhanced generation of ROS. When MDA-MB-231 and MCF-7 cells were treated with 20 μg/mL UA, an absolute decrease in cell viability of 47.6% and 48.6%, enhancement of 1.35% and 1.10% in early apoptosis, and 21.90% and 21.35% in late apoptosis, respectively and G0 /G1 phase, S phase, G2 /M phase cell cycle arrest was noticed. The gene expression studies revealed that UA could significantly (p < 0.001) downregulate the expression of EMT markers such as snail, slug, and fibronectin at molecular level. Further, the obtained in vitro results of snail, slug, and fibronectin were subjected to quantum-polarized-ligand (QM/MM) docking, which predicted that the in silico binding affinities of these three markers are in good correlation with strong hydrogen and van der Waal interactions to UA with -53.865, -48.971 and -40.617 MMGBSA (ΔGbind ) scores, respectively. The long-range molecular dynamics (50 ns) simulations have showed more consistency by UA. These findings conclude that UA inhibits breast cancer cells growth and proliferation through regulating the expression of key EMT marker genes, and thus UA is suggested as a potential anticancer agent.

Isorhamnetin induces cell cycle arrest and apoptosis by triggering DNA damage and regulating the AMPK/mTOR/p70S6K signaling pathway in doxorubicin-resistant breast cancer

BACKGROUND

Acquired resistance to doxorubicin (DOX) inevitably limits its clinical use against breast cancer (BC). Isorhamnetin (IS), a native flavonoid which extensively available in vegetables, fruits, and phytomedicine, has been deemed to the probable cancer chemopreventive agent in preceding explorations since it exhibits satisfied antitumor activity. So far, the strategy for alleviating DOX resistance by using IS as a sensitizer against resistant BC has not yet been covered.

PURPOSE

To investigate the effect of IS on potentiating the chemoreceptivity of drug-resistant BC cells to DOX in vitro and in vivo and elucidate the possible molecular mechanisms.

METHODS

MTS assays, colony formation assays, three-dimensional (3D) tumor spheroid model, and migration assay were deployed to verify the inhibiting action of IS in the presence or absence of DOX on resistant BC cells in vitro. Apoptosis, cell cycle regulation, and endocellular reactive oxygen species (ROS) were determined by flow cytometry. Protein levels were monitored by western blotting. Nuclear staining and EdU proliferation were photographed with a confocal laser scanning microscope. The effects of the IS and DOX combination on the tumorigenesis in the xenograft experiments were evaluated for further confirming the in vitro cytotoxicity.

RESULTS

IS significantly inhibited cell proliferation and migration and enhanced the antitumor competence of DOX against resistant BC cells both in vitro and in vivo. Adjuvant IS (50 μM) effectively enhanced the proapoptotic impacts of DOX in resistant BC cells (35.38 ± 3.18%, vs. 5.83 ± 0.68% in the DOX group) by suppressing the expression of bcl 2 in addition to enhancing cleaved caspase 3, ultimately leading to DNA condensation and fragmentation. IS (20, 30, and 50 μM) treatments induced significant increases in the G2/M populations (41.60 ± 1.28%, 44.60 ± 1.14%, and 50.64 ± 0.67%, vs. 35.84 ± 1.56% in the untreated control in MCF7/ADR cells, p < 0.01) via regulating CDK1/Cyclin B1 complex expression, subsequently triggering the inhibition of BC proliferation. In addition, IS (10, 20, 30, and 50 μM) stimulated the production of interstitial ROS in MCF7/ADR cells, by 3.99-, 4.20-, 6.29-, and 6.78-fold, respectively, versus the untreated group (p < 0.001), which were involved in DNA damage and AMPK-caused intercept of the mTOR/p70S6K signaling.

CONCLUSION

Our study suggested the anti-breast cancer actions of IS as a DOX sensitizer and expounded the underlying molecular mechanisms, showing that IS could be deemed to a capable alternative for resistant BC cure.