Amentoflavone triggers cell cycle G2/M arrest by interfering with microtubule dynamics and inducing DNA damage in SKOV3 cells

Cytosolic JNK-dependent microtubule reassembly protects Jurkat leukemia cells from selenite-induced apoptosis

BACKGROUND

Selenite at high dosage exhibits great potential in curing tumors. It has been shown that selenite inhibits tumor growth through regulation of microtubule dynamics, however, the exact underlying mechanisms remained to be fully elucidated.

METHODS & RESULTS

Western blots were carried out to evaluate expression level of different molecules. Our current study discovered that selenite induced microtubule disassembly, cell cycle arrest and finally resulted in apoptosis in Jurkat leukemia cells, while during this process disassembled tubulins were re-organized after long-term exposure to selenite. Furthermore, JNK was activated in the cytoplasm of selenite-treated Jurkat cells, and inhibition of JNK activity successfully prevented the process of microtubule re-assembly. Moreover, inactivation of JNK further enhanced selenite-induced cell cycle arrest and apoptosis. According to the results from cell counting-8 assay, blockage of microtubule re-assembly by colchicine further inhibited Jurkat cell viability after exposure to selenite. Experiments in a xenograft model also proved that selenite could alter JNK activity, destroy microtubule structure and inhibit cell division in vivo. Moreover, TP53, MAPT and YWHAZ were identified to be three most confident interactors that link JNK to microtubule assembly using PPIs analysis.

CONCLUSION

Our study indicated that cytosolic JNK-dependent microtubule re-organization took a protective function during selenite-induced apoptosis, while inhibition of this process would finally enhance the anti-tumor effect of selenite.

Chemopreventive mechanisms of amentoflavone: recent trends and advancements

In parallel to the continuous rise of new cancer cases all over the world, the interest of scientific community in natural anticancer agents has steadily been increased. In the past decades, numerous phytochemicals have been shown to possess a strong anticancer potential in preclinical conditions. One of such interesting compounds, derived from different plants such as ginkgo, hinoki, and St. John`s wort, is amentoflavone. In this review article, a wide range of anticancer properties of this natural biflavone are described, revealing its ability to suppress the malignant growth and lead tumor cells to apoptotic death, besides impeding also angiogenic and metastatic processes. Therefore, amentoflavone can be considered a potential lead compound for the development of novel anticancer drug candidates, definitely deserving further in vivo studies and also initiation of clinical trials. It is expected that this plant biflavone might be important, either alone or in combination with the current standard chemotherapeutics, in providing some alleviation for the continuous rise of global cancer burden.

Insights Into Amentoflavone: A Natural Multifunctional Biflavonoid

Amentoflavone is an active phenolic compound isolated from Selaginella tamariscina over 40 years. Amentoflavone has been extensively recorded as a molecule which displays multifunctional biological activities. Especially, amentoflavone involves in anti-cancer activity by mediating various signaling pathways such as extracellular signal-regulated kinase (ERK), nuclear factor kappa-B (NF-κB) and phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), and emerges anti-SARS-CoV-2 effect via binding towards the main protease (Mpro/3CLpro), spike protein receptor binding domain (RBD) and RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. Therefore, amentoflavone is considered to be a promising therapeutic agent for clinical research. Considering the multifunction of amentoflavone, the current review comprehensively discuss the chemistry, the progress in its diverse biological activities, including anti-inflammatory, anti-oxidation, anti-microorganism, metabolism regulation, neuroprotection, radioprotection, musculoskeletal protection and antidepressant, specially the fascinating role against various types of cancers. In addition, the bioavailability and drug delivery of amentoflavone, the molecular mechanisms underlying the activities of amentoflavone, the molecular docking simulation of amentoflavone through in silico approach and anti-SARS-CoV-2 effect of amentoflavone are discussed.

Abu Ali O, Fayad E, Ahmed Gaafar AG, Zakaria MY. Design and Synthesis of Newly Synthesized Acrylamide Derivatives as Potential Chemotherapeutic Agents against MCF-7 Breast Cancer Cell Line Lodged on PEGylated Bilosomal Nano-Vesicles for Improving Cytotoxic Activity

Cancer is a multifaceted disease. With the development of multi drug resistance, the need for the arousal of novel targets in order to avoid these drawbacks increased. A new series of acrylamide derivatives was synthesized from starting material 4-(furan-2-ylmethylene)-2-(3,4,5-trimethoxyphenyl)oxazol-5(4H)–one (1), and they are evaluated for their inhibitory activity against β-tubulin polymerization. The target molecules 2–5 d were screened for their cytotoxic activity against breast cancer MCF-7 cell line. The results of cytotoxicity screening revealed that compounds 4e and 5d showed good cytotoxic profile against MCF-7 cells. Compounds 4e produced significant reduction in cellular tubulin with excellent β-tubulin polymerization inhibition activity. In addition, compound 4e exhibited cytotoxic activity against MCF-7 cells by cell cycle arrest at pre-G1 and G2/M phases, as shown by DNA flow cytometry assay. Aiming to enhance the limited aqueous solubility and, hence, poor oral bioavailability of the prepared lead acrylamide molecule, 4e-charged PEGylated bilosomes were successfully fabricated via thin film hydration techniques as an attempt to improve these pitfalls. 2³ full factorial designs were manipulated to examine the influence of formulation variables: types of bile salt including either sodium deoxy cholate (SDC) or sodium tauro cholate (STC), amount of bile salt (15 mg or 30 mg) and amount of DSPE–mPEG-2000 amount (25 mg or 50 mg) on the characteristics of the nanosystem. The F7 formula of entrapment efficiency (E.E% = 100 ± 5.6%), particle size (PS = 280.3 ± 15.4 nm) and zeta potential (ZP = −22.5 ± 3.4 mv) was picked as an optimum formula with a desirability value of 0.868. Moreover, prominent enhancement was observed at the compound’s cytotoxic activity (IC₅₀ = 0.75 ± 0.03 µM) instead of (IC₅₀ = 2.11 ± 0.19 µM) for the unformulated 4e after being included in the nano-PEGylated bilosomal system.