Growth suppression of human transformed cells by treatment with bark extracts from a medicinal plant, Terminalia
1National Institute of Bioscience and Human Technology, Tsukuba, Ibaraki, Japan.
Abstract:
We have investigated the effects of acetone and methanol extracts of a medicinal plant, Terminalia arjuna, on the growth of human normal fibroblasts (WI-38), osteosarcoma (U2OS), and glioblastoma (U251) cells in vitro. We found that both extracts at 30 microg and 60 microg/ml concentrations inhibit the growth of transformed cells; the growth of normal cells was least affected. Although the transformed cells appeared to have fragmented nucleus by Hoechst staining, no deoxy-ribonucleic acid laddering effect was observed. In response to the extract treatment, the tumor suppressor protein, p53, was induced in U2OS but not in U251 and WI-38 cells. A cyclin-dependent kinase inhibitor, p21WAF1, was induced in transformed cells only. The study suggests that the bark extract of medicinal plant, T. arjuna, has components that can induce growth arrest of transformed cells by p53-dependent and -independent pathways.
Insights
Terminalia arjuna bark extracts inhibit cancer cell growth while sparing normal cells. This medicinal plant extract shows potential for cancer therapy by inducing cell cycle arrest through p53-dependent and -independent pathways.
Area of Science:
- Phytochemistry
- Cell Biology
- Cancer Research
Background:
- Medicinal plants are a rich source of bioactive compounds.
- Terminalia arjuna is traditionally used for various ailments.
- Understanding the anti-cancer properties of T. arjuna is of therapeutic interest.
Purpose of the Study:
- To investigate the in vitro effects of Terminalia arjuna extracts on normal and cancer cell lines.
- To determine the impact of T. arjuna on cell proliferation and identify underlying molecular mechanisms.
Main Methods:
- Acetone and methanol extracts of T. arjuna bark were prepared.
- Human normal fibroblasts (WI-38), osteosarcoma (U2OS), and glioblastoma (U251) cells were treated with extracts.
- Cell growth inhibition was assessed, and nuclear morphology was examined using Hoechst staining.
- Expression of tumor suppressor protein p53 and cyclin-dependent kinase inhibitor p21WAF1 was analyzed.
Main Results:
- Both acetone and methanol extracts inhibited the growth of U2OS and U251 cancer cells at 30 and 60 microg/ml.
- Normal WI-38 cells showed minimal growth inhibition.
- Nuclear fragmentation was observed in transformed cells, but DNA laddering was absent.
- p53 was induced in U2OS cells, while p21WAF1 was induced in both U2OS and U251 cells.
Conclusions:
- Terminalia arjuna bark extracts possess anti-proliferative activity against human cancer cells in vitro.
- The extracts induce growth arrest in transformed cells via both p53-dependent and p53-independent mechanisms.
- T. arjuna extracts demonstrate selective toxicity towards cancer cells, suggesting potential therapeutic applications.
