Duguetia confinis Engl. & Diels (Annonaceae) inhibitory and cytotoxic effects on breast adenocarcinoma growth both in vitro and in vivo.

Background: Breast cancer is ranked as the most common malignant tumor in women globally with ∼ 2.3 million new cases (11.7 %) diagnosed in 2020. The multiple drawbacks associated with treatments, prompt researchers and patients to search for alternative therapy. Plants continue to offer encouraging leads, in particular those of the Annonaceae family, to which belongs Duguetia confinis, used by Cameroonian traditional healers to fight cancers. This study was aimed at investigating the effect of Duguetia confinis against human breast cancer cells. This was carried out by investigating the cytotoxicity, underlying mechanism of action and chemopreventive potential of D. confinis on 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer. Methods: To achieve this goal, the ethanolic extract of the bark of D. confinis was prepared and assayed for its ability to inhibit cell growth, cell proliferation and clone formation. Furthermore, cell death mechanisms, cell cycle progression and anti-metastatic potential were investigated. The in vivo study consisted in a once-off administration of 50 mg/kg BW DMBA (in olive oil, s.c) from the 10th day after pretreatment with D. confinis extract (50 and 100 mg/kg BW) or standards [tamoxifen (3.3 mg/kg) and letrozole (1 mg/kg)] or leaf extract of Annona muricata L. (200 mg/kg as pharmacological control). Normal and negative controls received vehicle (3 % ethanol). The treatment of animals was done for 20 weeks, followed by the assessment of the incidence, burden and volume of tumors, breast cancer biomarker (CA 15-3), antioxidant status, inflammatory status and histopathology profile. The LD50 of D. confinis extract was estimated according to OECD guideline 423. Results: D. confinis displayed cytotoxicity at 80 µg/mL on all the tested breast cancer cell lines. It induced apoptosis and caused a blockade at G0/G1; S-phase of MDA-MB 231 cells, thus, suggesting anticancer potential. A significant concentration-dependent antimetastatic potential was observed with D. confinis extract at 50 (p < 0.05) and 100 (p < 0.01) µg/mL, evidenced by a reduction in cell migration, chemotaxis and increased adhesion to extracellular matrix. With respect to the chemopreventive study, D. confinis was able to prevent the onset of breast adenocarcinoma in Wistar rats by preventing the growth of tumor mass and volume, as well as the histopathological severity of the disease. This was achieved through the modulation of antioxidant parameters (SOD, CAT, MDA) and inflammatory parameters (IL-12, IL-6, INF- gamma, TNF). Also, the LD50 of D. confinis extract was greater than 2000 mg/kg, indicating low acute toxicity and thus, favorable for therapeutic use. Conclusion: In summary, this study outlines for the first time the beneficial effect of D. confinis as a plant candidate in the fight against breast cancer just like other species of the Annonaceae family. However, further research studies are still warranted regarding its bioactive components, and in depth investigation of its anticancer mechanism of action are also needed.

Comparative anticancer effects of Annona muricata Linn (Annonaceae) leaves and fruits on DMBA-induced breast cancer in female rats.

BACKGROUND: Numerous studies have reported the anti-cancer effects of different parts of Annona muricata Linn, however ; most of them focused on the in vitro evaluation of isolates. In vivo evidence on which part is best suited for breast cancer chemoprevention remains to be demonstrated. This is a comparative study of the effects of A. muricata fruit and leaves extracts on DMBA induced-breast cancer in rats. METHODS: Rats exposed to DMBA (50 mg/kg, s.c.), were treated with A. muricata fruit aqueous extract at 200 mg/kg BW (3 days/week or daily) and A. muricata Linn leaves ethanolic extract at 200 mg/kg daily. Positive control group received tamoxifen at 3.3 mg/kg, while the normal and diseased controls received vehicle. After 20 weeks of treatment, the tumor incidence, tumor burden, tumor volume, histopathology, protein and CA 15 - 3 levels as well as antioxidant status, pro-inflammatory cytokines were assessed. RESULTS: Thus, 100% of diseased rats presented cribriform ductal carcinoma of SBR grade III. A. muricata extracts (leaves and fruit) and tamoxifen significantly reduced death and tumor incidences, volume and weight of the tumors, total protein and CA15-3 levels compared to the DMBA group. They exhibited antioxidant activity, through an increase in the GSH level and SOD and catalase activities with reduced levels of MDA compared to DMBA group. TNF-α, IL-6 and INF-γ levels reduced with regards to A. muricata treatment. CONCLUSION: These results confirm the anti-breast cancer effect of A. muricata, however, the aqueous fruit extract was more potent than the ethanolic leaves extract.

Breast cancer cell growth arrest and chemopreventive effects of Passiflora edulis Sims (Passifloraceae) ethanolic leaves extract on a rat model of mammary carcinoma.

ETHNOPHARMACOLOGICAL RELEVANCE: Despite various prevention and treatment measures, the incidence and mortality due to breast cancer has been increasing globally. Passiflora edulis Sims is a plant used for the treatment of various diseases in traditional medicine, including cancers. AIM OF THE STUDY: To assess the anti-breast cancer activity of the ethanolic extract of P. edulis leaves in vitro and in vivo. MATERIAL AND METHODS: In vitro, the cell growth and proliferation were determined based on the MTT and BrdU assays. The flow cytometry was used to analyze the cell death mechanism while, cell migration, cell adhesion and chemotaxis were assayed for anti-metastatic potential. In vivo, 56 female Wistar rats aged 45-50 days (∼75 g) were exposed to 7,12-dimethylbenz(a)anthracene-DMBA except the normal group. Negative control group (DMBA) received solvent dilution throughout the study; standards groups (tamoxifen - 3.3 mg/kg BW and letrozole - 1 mg/kg BW) as well as P. edulis leaves ethanolic extract groups (50, 100 and 200 mg/kg) treated for 20 weeks. Tumor incidence, tumor burden and volume, CA 15-3 serum' level, antioxidant, inflammatory status and histopathology were assessed. RESULTS: P. edulis extract showed a significant and concentration-dependent inhibition of MCF-7 and MDA-MB 231 cells growth at 100 µg/mL. It inhibited cell proliferation and clones' formation and induced apoptosis in MDA-MB 231 cells. The migration of cell into the zone freed of cells and the number of invading cells after the 48 and 72 h were significantly diminished while, it increased their adherence to collagen and fibronectin extracellular matrix as does Doxorubicin. In vivo, all rats in the DMBA group exhibited a significant (p < 0.001) increase in tumor volume, tumor burden and grade (adenocarcinoma of SBR III) and pro-inflammatory cytokine levels (TNF-α, INF-γ, IL-6 and IL-12). P. edulis extract at all tested doses significantly inhibited the DMBA-induced increase in tumor incidence, tumor burden and grade (SBR I) as well as pro-inflammatory cytokines. Moreover, it increased enzymatic and non-enzymatic antioxidants (SOD, catalase, and GSH) and decreased MDA levels although a greater effect was observed with Tamoxifen and Letrozole. P. edulis has medium content on polyphenols, flavonoids and tannins. CONCLUSION: P. edulis has chemo-preventive effects against DMBA-induced breast cancer in rats probably through its antioxidative, anti-inflammatory and apoptosis-inducing potentials.