Switching from Aromatase Inhibitors to Dual Targeting Flavonoid-Based Compounds for Breast Cancer Treatment

(E)-1-(3-(3-Hydroxy-4-Methoxyphenyl)-1-(3,4,5-Trimethoxyphenyl)allyl)-1H-1,2,4-Triazole and Related Compounds: Their Synthesis and Biological Evaluation as Novel Antimitotic Agents Targeting Breast Cancer

Background/Objectives: The synthesis of (E)-1-(1,3-diphenylallyl)-1H-1,2,4-triazoles and related compounds as anti-mitotic agents with activity in breast cancer was investigated. These compounds were designed as hybrids of the microtubule-targeting chalcones, indanones, and the aromatase inhibitor letrozole. Methods: A panel of 29 compounds was synthesized and examined by a preliminary screening in estrogen receptor (ER) and progesterone receptor (PR)-positive MCF-7 breast cancer cells together with cell cycle analysis and tubulin polymerization inhibition. Results: (E)-5-(3-(1H-1,2,4-triazol-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-1-en-1-yl)-2-methoxyphenol 22b was identified as a potent antiproliferative compound with an IC50 value of 0.39 mM in MCF-7 breast cancer cells, 0.77 mM in triple-negative MDA-MB-231 breast cancer cells, and 0.37 mM in leukemia HL-60 cells. In addition, compound 22b demonstrated potent activity in the sub-micromolar range against the NCI 60 cancer cell line panel including prostate, melanoma, colon, leukemia, and non-small cell lung cancers. G2/M phase cell cycle arrest and the induction of apoptosis in MCF-7 cells together with inhibition of tubulin polymerization were demonstrated. Immunofluorescence studies confirmed that compound 22b targeted tubulin in MCF-7 cells, while computational docking studies predicted binding conformations for 22b in the colchicine binding site of tubulin. Compound 22b also selectively inhibited aromatase. Conclusions: Based on the results obtained, these novel compounds are suitable candidates for further investigation as antiproliferative microtubule-targeting agents for breast cancer.

Formulation of Morus alba extract loaded solid lipid nanoparticles: in silico, characterizations, and in vitro cytotoxicity study

OBJECTIVE

This study aimed to formulate Morus alba leaf extract (MAE) loaded solid lipid nanoparticles (SLNs) and investigate its cytotoxic potential using MDA-MB231 cell line.

SIGNIFICANCE

SLNs can protect MAE from degradation, enhance cytotoxicity potential, and making them suitable for various therapeutic areas.

METHODS

SLNs were developed using high-pressure homogenization method, and the formulations were optimized based on particle size, zeta potential, % entrapment efficiency (EE), and % cumulative drug release (CDR). The in vitro cytotoxic efficacy of MAE-loaded SLNs was evaluated through apoptosis assays and compared to that of free MAE.

RESULTS

The particle size, zeta potential, % EE, and % CDR of optimized SLNs were found 116.3 nm, -26.18 mV, 89.30%, and 79.4%, respectively. MAE-loaded SLNs demonstrated significantly greater cytotoxic effects than the MAE (p < 0.05). SLNs induced less inhibition in the G0/G1 phase but showed marked inhibition in the S phase (9.7 ± 1.7%) and G2/M phase (2.2 ± 0.6%), indicating effective disruption of DNA replication and cell division, with significant cytotoxicity compared to control cells. The percentage of total apoptosis was 72.49 ± 2.7% for MAE alone and 81.46 ± 2.9% for MAE loaded SLNs, demonstrating a notably higher apoptosis rate for the SLNs formulation (p < 0.05). These findings indicated that MAE loaded SLNs significantly enhance the apoptotic and cytotoxic impact compared to MAE.

CONCLUSION

These results proved that MAE loaded SLNs as a promising nano carrier system to improve the therapeutic performance of MAE.

Aromatase inhibitors for the treatment of breast cancer: An overview (2019-2023)

Aromatase inhibition is considered a legitimate approach for the treatment of ER-positive (ER+) breast cancer as it accounts for more than 70% of breast cancer cases. Aromatase inhibitor therapy has been demonstrated to be highly effective in decreasing tumour size, increasing survival rates, and lowering the chance of cancer recurrence. The present review deliberates the pathophysiology and the role of aromatase in estrogen biosynthesis. Estrogen biosynthesis, various androgens, and their function in the human body have also been discussed. The salient aspects of the aromatase active site, its mode of action, and AIs, along with their intended interactions with presently FDA-approved inhibitors, have been briefly discussed. It has been detailed how different reported AIs were designed, their SAR investigations, in silico analysis, and biological evaluations. Various AIs from multiple origins, such as synthetic and semi-synthetic, have also been discussed.

Trapping of thermally generated ortho- and para-quinone methides by imidazoles and pyrazoles: a simple route to green synthesis of benzopyrone-azole hybrids and their evaluation as α-glucosidase inhibitors

An efficient green approach for the trapping of in situ generated ortho-and para-quinone methide intermediates by imidazoles and pyrazoles has been developed. A wide range of quinone methide precursors based on simple phenols are compatible with the experimental protocol under mild thermal conditions. This methodology was demonstrated to be suitable for the synthesis of methylene-linked benzopyrone-azole hybrids using naturally occurring coumarin and chromone Mannich bases. In most cases, the products were isolated in good to excellent yields without chromatographic purification. In vitro studies showed that some of the synthesized compounds exhibit inhibitory activity towards α-glucosidase.

Evaluating flavonoids as potential aromatase inhibitors for breast cancer treatment: In vitro studies and in silico predictions

Aromatase inhibitors are commonly employed in the treatment of hormone-dependent breast cancers, and flavonoids have emerged as a promising alternative to existing drug classes with unfavorable side effects. In this study, we conducted in vitro investigations into CYP19A1 (aromatase) inhibitory potential of 14 flavonoids, including pinocembrin, sakuranetin, eriodictyol, liquiritigenin, naringenin, hesperetin, flavanone, baicalein, chrysin, nobiletin, luteolin, sinensetin, tricin, and primuletin. Flavonoids displaying inhibitory activity were further assessed using in silico tools, such as molecular docking to predict binding affinities, as well as SwissADME, admetSAR, and QED (Quantitative Estimate of Drug-likeness) for drug-likeness prediction. Flavonoids with IC50 values less than 10 μM, pinocembrin, eriodictyol, naringenin, liquirtigenin, sakuranetin, and chrysin, exhibited favorable physicochemical properties and ADME profiles, suggesting their potential for development as novel flavonoid-based aromatase inhibitors. This study would provide valuable insights for the development of flavonoid-based aromatase inhibitors for the treatment of breast cancer.

Review on Natural Agents as Aromatase Inhibitors: Management of Breast Cancer

Breast cancer is a prevalent type of cancer that is typically hormone-dependent, caused by estrogen. Aromatase inhibitors are frequently utilised in the treatment of hormonereceptor- positive breast cancer because they prevent the enzyme aromatase from converting androgens to estrogens. Natural medicines with aromatase inhibitory characteristics have attracted interest as potential alternatives or complementary therapy to manufactured medications. This review discusses the function of natural agents as aromatase inhibitors in treating breast cancer. A variety of natural compounds have been investigated for their capacity to inhibit aromatase activity and lower estrogen levels. These agents include resveratrol from red wine and grapes, curcumin from turmeric extract and green teahigh in catechins, and other flavonoids such as genistein, luteolin and quercetin. It has been demonstrated that by decreasing estrogen synthesis, they can slow the growth of breast cancer cells that are dependent on estrogen. However, the clinical evidence supporting their efficacy and safety in breast cancer treatment is inadequate. More research is required to investigate the therapeutic potential of natural medicines, such as aromatase inhibitors, in treating breast cancer. The clinical trials are required to assess their efficacy, appropriate doses, and potential interactions with other therapies. In conclusion, natural aromatase inhibitory drugs are promising adjuncts in the treatment of hormone receptor-positive breast cancer. Their clinical value and safety profile, however, require additional investigation.