Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Substances from African medicinal plants could help stop tumor growth

10.06.2013
Experiments using benzophenones derived from plants originating in Cameroon produce evidence that these may be effective against multi-drug resistant cancers

African medicinal plants contain chemicals that may be able to stop the spread of cancer cells. This is the conclusion of researchers following laboratory experiments conducted at Johannes Gutenberg University Mainz (JGU).

The plant materials will now undergo further analysis in order to evaluate their therapeutic potential. "The active substances present in African medicinal plants may be capable of killing off tumor cells that are resistant to more than one drug. They thus represent an excellent starting point for the development of new therapeutic treatments for cancers that do not respond to conventional chemotherapy regimens," explained Professor Thomas Efferth of the Institute of Pharmaceutical Sciences and Biochemistry – Therapeutic Life Sciences at Mainz University. For the past four years, Efferth and biochemist Dr. Victor Keute of the University of Dschang in Cameroon have been studying the active substances in African plants such as the giant globe thistle, wild pepper, speargrass, and Ethiopian pepper.

Multi-drug resistance is one of the most feared problems in cancer therapy because in such cases most of the standard chemical cancer drugs used in therapy fail and the patient's chance of survival is thus dramatically reduced. The problem cannot usually be resolved by simply increasing the dosage as this also results in the exacerbation of undesirable side effects. "We are now looking for substances that can both break down tumor resistance and not produce side effects," continued Efferth, who also works with medicinal plants used in traditional Chinese medicine.

Many plants contain toxic substances that they use to protect themselves against predators and microbial diseases. Over the course of millions of years during which life has evolved on earth plants have managed to appropriate certain molecules to help them to offset their main disadvantage in the face of their enemies, i.e., their immobility and lack of an immune system. The challenge for the pharmacologists is now to determine which plant substances are medicinal and which are simply poisonous and dangerous.
During the joint project with Mainz, the Cameroonian scientist Victor Kuete has examined more than 100 spices and plants from his homeland for their cytotoxic effects on cancer cells. Awarded a Humboldt Research Fellowship, he can now continue and extend his investigations as a member of Thomas Efferth's work group in Mainz. "We have already found an entire series of benzophenones and other phytochemicals that are able to elude resistance mechanisms and thus offer many new opportunities for continued research," said Efferth.

The researchers are focusing on three different resistance mechanisms. Transporter-mediated resistance prevents drugs taking effect because a substance called P-glycoprotein promotes their efflux from cancer cells. In the case of tumor-suppressor-gene-mediated resistance, a mutation in protein p53 means that the cancer cells do not die but are resistant and become increasingly aggressive. Lastly, in oncogene-mediated resistance, the epidermal growth factor receptor (EGFR) sends signals into the interior of cells causing tumors to grow faster. The researchers in Mainz have cellular models of all three resistance mechanisms that will enable them to appropriately test the effectiveness of the substances obtained from plants.

In their latest of a total of eight publications produced to date, the research team reports that four naturally occurring benzophenones can prevent the proliferation of the tested cancer cell lines, including multi-drug resistant strains. "The benzophenones investigated are potentially cytotoxic substances that need to be more extensively investigated with the aim of developing new cancer drugs that are effective against susceptible and resistant cancers", claims the article recently published in the scientific journal Phytomedicine.

Images:
http://www.uni-mainz.de/bilder_presse/09_pharma_heilpflanzen_piper_capensis.jpg
Wild pepper seeds
photo: Victor Kuete, Institute of Pharmaceutical Sciences and Biochemistry – Therapeutic Life Sciences

http://www.uni-mainz.de/bilder_presse/09_pharma_heilpflanzen_echinops_giganteus.jpg
Sections of the root of the giant globe thistle
photo: Victor Kuete, Institute of Pharmaceutical Sciences and Biochemistry – Therapeutic Life Sciences

Publications:
Victor Kuete et al.
Cytotoxicity and modes of action of four naturally occuring benzophenones: 2,2_,5,6_-Tetrahydroxybenzophenone, guttiferone E, isogarcinol and isoxanthochymol
Phytomedicine, April 2013
DOI: 10.1016/j.phymed.2013.02.003

Victor Kuete et al.
Anticancer Activities of Six Selected Natural Compounds of Some Cameroonian Medicinal Plants
PLoS ONE, August 2011
DOI:10.1371/journal.pone.0021762

Further information:
Professor Dr. Thomas Efferth
Pharmaceutical Biology
Institute of Pharmaceutical Sciences and Biochemistry – Therapeutic Life Sciences Johannes Gutenberg University Mainz (JGU)
D 55099 Mainz, GERMANY
phone +49 6131 39-25751
fax +49 6131 39-23752
e-mail: efferth@uni-mainz.de
http://www.pharmazie.uni-mainz.de/125.php [in German]

Weitere Links:
http://dx.doi.org/10.1016/j.phymed.2013.02.003 (Article in Phytomedicine)

Petra Giegerich | idw
Further information:
http://www.uni-mainz.de

More articles from Life Sciences:

nachricht In living color: Brightly-colored bacteria could be used to 'grow' paints and coatings
20.02.2018 | University of Cambridge

nachricht Computers aid discovery of new, inexpensive material to make LEDs with high color quality
20.02.2018 | University of California - San Diego

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

New tech for commercial Lithium-ion batteries finds they can be charged 5 times fast

20.02.2018 | Power and Electrical Engineering

Hidden talents: Converting heat into electricity with pencil and paper

20.02.2018 | Materials Sciences

Rare find from the deep sea

20.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>