Indigo has a long reputation for its medicinal effects. This is now becoming obvious from research as one of its medicinal compounds has been found to prevent the growth of cancer cells.
Researchers from the Beckman Research Institute have determined that a constituent of the Indigo herb called indirubin prevents leukemia cells from growing. Another recent study from Korea’s Chosun University has found that indirubin stops lung cancer cell growth. And a 2011 study from Ohio State University showed indirubin stops brain cancer cells from growing.
The leukemia research, supported by the City of Hope Comprehensive Cancer Center’s department of molecular medicine, applied indirubin to human chronic myelogenous leukemia tumor cells. They found that the indirubin blocked the cancer cells' signalling systems and their ability to regenerate their cell membranes—a process called autophosphorylation.
The mechanism revealed by the study involved blocking processes of particular genes within the tumor cells. Indirubin blocks the process of a protein called the Signal Transducer and Activator of Transcription 5 (STAT5) protein. In addition, a group of molecules called Src family kinases (SFKs) is blocked by indirubin, which prevents the cell from activating phosphorylation. This leads to cell death among the leukemia cells.
The lung cancer research found that indirubin also blocked phosphorylation activities, and reduced the polo-like kinase (PLK) activity, which also leads to the cell death of human lung cancer cells.
This is not the first study that has shown that indirubin shuts down cancer cells. Other studies have shown that indirubin treats leukemia cancer cells, and a study released last year showed that indirubin blocked the growth of brain cancer cells.
Indirubin promising anti-cancer strategy
Indirubin is now seen as one of the most promising anti-cancer strategies available. Thanks to mother nature.Indirubin was discovered well over a decade ago, when researchers were trying to isolate the compound within the Traditional Chinese Herbal formula called Danggui Longhui Wan that seemed to block leukemia cancer from growing. The Danggui Longhui Wan formula contains 11 different herbs, so, through the process of elimination, researchers have been able to gradually isolate which plant and which component the mechanism was coming from.
Eventually, the plant found to block cancer growth indigo, or Indigofera sumatrana, which is also called Indigofera tinctoria, and the active constituent was called indirubin.
It should be noted that whole plant herbs and herbal combinations are used in traditional medicine because the variety of multiple constituents help buffer the active ones, providing a higher level of safety and lower levels of side effects.
REFERENCES:
Nam S, Scuto A, Yang F, Chen W, Park S, Yoo HS, Konig H, Bhatia R, Cheng X, Merz KH, Eisenbrand G, Jove R. Indirubin derivatives induce apoptosis of chronic myelogenous leukemia cells involving inhibition of Stat5 signaling. Mol Oncol. 2012 Feb 17.
Yoon HE, Kim SA, Choi HS, Ahn MY, Yoon JH, Ahn SG. Inhibition of Plk1 and Pin1 by 5'-nitro-indirubinoxime suppresses human lung cancer cells. Cancer Lett. 2012 Mar;316(1):97-104.
Williams SP, Nowicki MO, Liu F, Press R, Godlewski J, Abdel-Rasoul M, Kaur B, Fernandez SA, Chiocca EA, Lawler SE. Indirubins decrease glioma invasion by blocking migratory phenotypes in both the tumor and stromal endothelial cell compartments. Cancer Res. 2011 Aug 15;71(16):5374-80.
Indigofera photo by Leonora Enking