Apigenin alleviates resistance to doxorubicin in breast cancer cells by acting on the JAK/STAT signaling pathway

Nano co-delivery of doxorubicin and plumbagin achieves synergistic chemotherapy of hepatocellular carcinoma

Doxorubicin (DOX) is a chemotherapy drug used for hepatocellular carcinoma (HCC) treatment, but its effectiveness can be dramatically dampened by cancer cell chemoresistance. Signal transducer and activator of transcription 3 (STAT3) is implicated with drug resistance in a range of cancers (e.g., HCC), and the STAT3 inhibition can reverse the resistance of cancer cells to chemotherapeutic drugs. In the present study, a combination regimen to improve the efficiency of DOX was provided via the STAT3 blockade using plumbagin (PLB). A poly(lactic-co-glycolic acid) decorated by polyethylene glycol and aminoethyl anisamide was produced in the present study with the hope of generating the nanoparticles for co-delivery of DOX and PLB. The resulting co-formulation suppressed the STAT3 activity and achieved the synergistic chemotherapy, which led to tumor inhibition in the mice with subcutaneous DOX-resistant HCC, without causing any toxicity. The present study reveals the synergism of DOX and PLB, and demonstrates a promising combinatorial approach for treating HCC.

Natural products and derivatives for breast cancer treatment: From drug discovery to molecular mechanism

BACKGROUND

Breast cancer stands as the most common malignancy among women globally and a leading cause of cancer-related mortality. Conventional treatments, such as surgery, hormone therapy, radiotherapy, chemotherapy, and small-molecule targeted therapy, often fall short of addressing the complexity and heterogeneity of certain breast cancer subtypes, leading to drug resistance and metastatic progression. Thus, the search for novel therapeutic targets and agents is imperative. Given their low toxicity and abundant variety, natural products and their derivatives are increasingly considered valuable sources for small-molecule anticancer drugs.

PURPOSE

This review aims to elucidate the pharmacological impacts and underlying mechanisms of active compounds found in select natural products and their derivatives, primarily focusing on breast cancer treatment. It intends to underscore the potential of these substances in combating breast cancer and guide future research directions for the development of natural product-based therapeutics.

METHODS

We conducted comprehensive searches in electronic databases such as PubMed, Web of Science, and Scopus until October 2023, using keywords such as 'breast cancer', 'natural products', 'derivatives', 'mechanism', 'signaling pathways', and various keyword combinations.

RESULTS

The review presents a spectrum of phytochemicals, including but not limited to flavonoids, polyphenols, and alkaloids, and examines their actions in various animal and cellular models of breast cancer. The anticancer effects of these natural products and derivatives are manifested through diverse mechanisms, including induction of cell death via apoptosis and autophagy, and suppression of tumor angiogenesis.

CONCLUSION

An increasing array of natural products and their derivatives are proving effective against breast cancer. Future therapeutic strategies can benefit from strategic enhancement of the anticancer properties of natural compounds, optimization for targeted action, improved bioavailability, and minimized side effects. The forthcoming research on natural products should prioritize these facets to maximize their therapeutic potential.

Apigenin's Modulation of Doxorubicin Efficacy in Breast Cancer

Apigenin, a naturally derived flavonoid, is increasingly being acknowledged for its potential therapeutic applications, especially in oncology. This research explores apigenin's capacity to modulate cancer cell viability, emphasizing its roles beyond its minimal antioxidant activity attributed to its basic molecular structure devoid of hydroxyl groups. We investigated apigenin's effects on two breast cancer cell lines, estrogen-dependent MCF-7 and non-estrogen-dependent MDA-MB-231 cells. Our findings reveal that apigenin exerts a dose-dependent cytotoxic and anti-migratory impact on these cells. Interestingly, both apigenin and doxorubicin-a standard chemotherapeutic agent-induced lipid droplet accumulation in a dose-dependent manner in MDA-MB-231 cells. This phenomenon was absent in MCF-7 cells and not evident when doxorubicin and apigenin were used concurrently, suggesting distinct cellular responses to these treatments that imply that their synergistic effects might be mediated through mechanisms unrelated to lipid metabolism. A further chemoinformatics analysis indicated that apigenin and doxorubicin might interact primarily at the level of ATP-binding cassette (ABC) transporter proteins, with potential indirect influences from the AKT and MYC signaling pathways. These results highlight the importance of understanding the nuanced interactions between apigenin and conventional chemotherapeutic drugs, as they could lead to more effective strategies for cancer treatment. This study underscores apigenin's potential as a modulator of cancer cell dynamics through mechanisms independent of its direct antioxidant effects, thereby contributing to the development of flavonoid-based adjunct therapies in cancer management.

Novel (-)-arctigenin derivatives inhibit signal transducer and activator of transcription 3 phosphorylation and P-glycoprotein function resensitizing multidrug resistant cancer cells in vitro and in vivo

Multidrug resistance (MDR) is considered one of the significant chemotherapy failures of cancer patients and resulting in tumor recurrence and refractory cancer. The collateral sensitivity phenomenon is suggested as a potential alternative therapy for coring multidrug resistance in cancer. To achieve better effects and reduce toxicity, a polypharmacology strategy was applied. Arctigenin has been reported as a signal transducer and activator of transcription 3 (STAT3) inhibitor as an anticancer drug with low toxicity. However, the effective dosage of arctigenin was too high for re-sensitization in MDR cell lines. Therefore, we have designed and synthesized arctigenin derivatives and have evaluated their chemoreversal effects in KBvin and KB cells. The results conveyed that compounds 9, 10, and 12 displayed significant collateral sensitivity effects on MDR cancer cells, and the corresponding calculated RF values were 32, 174, and 133, respectively. In addition, compounds 9, 10, and 12 were identified to influence the activation of STAT3 and the function of P-glycoprotein in KBvin cells. Combining the active compounds (9, 10, and 12) with paclitaxel significantly inhibits MDR tumor growth in a zebrafish xenograft tumor model without toxicity. Thus, this study provided novel effective arctigenin derivatives and is considered a potential co-treatment with paclitaxel for treating MDR tumors.

Deciphering the modulatory role of apigenin targeting oncogenic pathways in human cancers

Cancer is a complicated malignancy controlled by numerous intrinsic and extrinsic pathways. There has been a significant increase in interest in recent years in the elucidation of cancer treatments based on natural extracts that have fewer side effects. Numerous natural product-derived chemicals have been investigated for their anticancer effects in the search for an efficient chemotherapeutic method. Therefore, the rationale behind this review is to provide a detailed insights about the anticancerous potential of apigenin via modulating numerous cell signaling pathways. An ingestible plant-derived flavonoid called apigenin has been linked to numerous anticancerous potential in numerous experimental and biological studies. Apigenin has been reported to induce cell growth arrest and apoptotic induction by modulating multiple cell signaling pathways in a wider range of human tumors including those of the breast, lung, liver, skin, blood, colon, prostate, pancreatic, cervical, oral, and stomach. Oncogenic protein networks, abnormal cell signaling, and modulation of the apoptotic machinery are only a few examples of diverse molecular interactions and processes that have not yet been thoroughly addressed by scientific research. Thus, keeping this fact in mind, we tried to focus our review towards summarizing the apigenin-mediated modulation of oncogenic pathways in various malignancies that can be further utilized to develop a potent therapeutic alternative for the treatment of various cancers.

The Chemo-Sensitizing Effect of Doxorubicin of Apple Extract-Enriched Triterpenic Complex on Human Colon Adenocarcinoma and Human Glioblastoma Cell Lines

Cancer cells' resistance to anticancer drugs represents a major clinical problem and the most important failure of treatment. Combination chemotherapy is more effective than monotherapy due to additive or synergistic effects. The aim of our research was to assess the effects of the combinations of apple extract's triterpenic compounds, individual triterpenic acids, and doxorubicin (DOX) on human colon adenocarcinoma (HT-29) and human glioblastoma (U-87) cell lines in 2D and 3D cultures. The effect of the combination of apple extracts, the triterpenic standards, and DOX against HT-29 and U-87 cell viability was tested by the MTT and spheroid growth assays. Cell line HT-29 was more sensitive to DOX when incubated with all tested apple extracts than DOX alone. Cell line HT-29 was the most strongly sensitive to DOX when it was treated with 5 µM oleanolic acid (change of EC₅₀ = -64.6% ± 4.4%) and with 5 µM ursolic acid (change of EC₅₀ = -61.9% ± 8.8%) in 2D culture. Meanwhile, cell line U-87 was the most strongly sensitive to DOX when treated with 2 µM betulinic acid (change of EC₅₀ = -45.1% ± 4.5%) in 2D culture. The combination of apple extract (E3) and DOX reduced the viability of HT-29 spheroids the most (spheroid viability reduced from -19.9% to -10.9%, compared to spheroids treated with DOX alone). Our study in 2D and 3D cultures showed that combining apple extract's triterpenic complexes or individual triterpenic acids with DOX may sensitize chemotherapeutic drugs and increase the cytotoxicity effects in HT-29 and U-87 cell lines.