Isorhamnetin inhibits cell proliferation and induces apoptosis in breast cancer via Akt and mitogen‑activated protein kinase kinase signaling pathways

Natural Polyphenols for Prevention and Treatment of Cancer

There is much epidemiological evidence that a diet rich in fruits and vegetables could lower the risk of certain cancers. The effect has been attributed, in part, to natural polyphenols. Besides, numerous studies have demonstrated that natural polyphenols could be used for the prevention and treatment of cancer. Potential mechanisms included antioxidant, anti-inflammation as well as the modulation of multiple molecular events involved in carcinogenesis. The current review summarized the anticancer efficacy of major polyphenol classes (flavonoids, phenolic acids, lignans and stilbenes) and discussed the potential mechanisms of action, which were based on epidemiological, in vitro, in vivo and clinical studies within the past five years.

Extraction and purification of total flavonoids from pine needles of Cedrus deodara contribute to anti-tumor in vitro

Background

Cedrus deodara is one of the traditional Chinese medicinal herbs that exhibits a line of biological activities. The current study extracted the total flavonoids from the pine needles of Cedrus deodara (TFPNCD), and investigated its anti-cancer effects in tumor cell lines.

Methods

The total flavonoids was extracted from pine needles of Cedrus deodara by ethanol hot refluxing and purified by HPD722 macroporous resin. The contents of total flavonoids and the active ingredients of TFPNCD were analyzed through UV and HPLC. MTT assay was used to investigate its inhibitory effect on tumor cell lines. The flow cytometry was employed to determine the apoptosis and cell cycle distribution after treated TFPNCD on HepG2 cells.

Results

The TFPNCD, in which the contents of total flavonoid reached up to 54.28 %, and the major ingredients of myricetin, quercetin, kaempferol and isorhamnetin in TFPNCD were 1.89, 2.01, 2.94 and 1.22 mg/g, respectively. The MTT assays demonstrated that TFPNCD inhibited the growth of HepG2 cells in a dose-dependent manner, with the IC₅₀ values of 114.12 μg/mL. By comparison, TFPNCD inhibited the proliferation to a less extent in human cervical carcinoma HeLa, gastric cancer MKN28 cells, glioma SHG-44 cells and lung carcinoma A549 than HepG2 cells. We found that even at the lower doses, the total flavonoids effectively inhibited the proliferation of HepG2 cells. Comparison of IC₅₀ values implicated that HepG2 cells might be more sensitive to the treatment with total flavonoids. TFPNCD was able to increase the population of HepG2 cells in G0 /G1 phase. Meanwhile, TFPNCD treatment increased the percentage of apoptotic HepG2 cells.

Conclusion

These data suggested that TFPNCD might have therapeutic potential in cancer through the regulation of cell cycle and apoptosis.