29/10/2015

Kinghorn contará, na 39ª RA, sobre décadas de busca por compostos bioativos contra o câncer

Cientista britânico radicado nos EUA já isolou centenas de compostos de plantas tropicais

Kinghorn é um entusiasta da química de produtos naturais: "O Brasil tem uma biodiversidade tremenda, sem paralelos, então é muito importante que tenha uma participação marcante no estudo de potenciais compostos úteis"

O doutor Douglas Kinghorn tem mais de três décadas dedicadas a entender compostos bioativos de plantas das florestas tropicais, sobretudo descobrir propriedades terapêuticas contra o câncer e outras doenças. Neste tempo, com seu grupo de pesquisadores, conseguiu isolar e caracterizar centenas de novos produtos naturais com potencial atividade anticancerígena – algumas chegaram às fases de testes pré-clínicos e clínicos. Ele é pesquisador do Comprehensive Cancer Center, da Universidade de Ohio State, nos EUA, onde leciona na Faculdade de Farmácia, e virá dar conferência na 39ª. Reunião Anual da SBQ, que será realizada em Goiânia, de 30 de maio a 2 de junho de 2016.

Kingorhn é um entusiasta da Química de Produtos Naturais e destaca o potencial brasileiro nessa área. "O Brasil tem uma biodiversidade tremenda, sem paralelos, então é muito importante que tenha uma participação marcante no estudo de potenciais compostos úteis", afirma. "Espero estimular os mais jovens a intensificarem estudos nesta área."

Formado em Farmácia em 1969, na Universidade de Bradford na região central da Inglaterra, o doutor Kinghorn mudou-se para os Estados Unidos nos anos 70 para realizar seu primeiro pós-doutorado, em Mississippi, na área de produtos naturais. "Durante minha graduação, gostei de estudar a ocorrência natural dos fármacos, e fiz meu doutorado em Londres nesta área, antes de me mudar para os Estados Unidos", disse Kinghorn ao Boletim da SBQ.

Kinghorn tem mais de 400 artigos publicados, índice h 53 e cerca de 15 mil citações. Desde 1994 é editor chefe do Journal of Natural Products, da American Chemical Society e da American Society of Pharmacognosy.

Leia a íntegra da entrevista concedida ao Boletim da SBQ:

What are the main achievements you have conquered in your 40 years of research for anticancer agents in (mainly tropical) plants?
Over the years, our focus has been on trying to elucidate the chemical structures of biologically active compounds from tropical rainforest plants. Owing to generous and sustained federal financial support, our group has isolated and characterized hundreds of new natural products from plants with potential anticancer activity, and some of these have been selected for preclinical and clinical development, such as betulinic acid, pervilleine A, and silvestrol. In addition, we have trained about 20 Ph.D. students and many postdoctoral fellows over the years who have participated in this work on anticancer agents.

How were you driven to this field of research?
Over 45 years ago, I trained at the undergraduate level in pharmacy, and one of the four major branches of pharmaceutical sciences at the time was pharmacognosy, the scientific study of naturally occurring drugs. As a result, I specialized in pharmacognosy for my Ph.D. degree at the University of London in the early 1970s, and then went on to postdoctoral work in the same field at the University of Mississippi in the United States. I was then fortunate enough to gain a faculty position at the University of Illinois at Chicago, where I stayed for about 28 years, and performed independent and collaborative work in searching for the biologically active principles of medicinal plants, inclusive of potential cancer chemotherapeutic agents. I have continued in this same field of research since commencing my present position at The Ohio State University in 2004. Other areas in which I have worked during my career are on antileishmanial agents, cancer chemopreventives (compounds that might prevent cancer from forming in the body), and natural sweeteners and taste modifiers.

How has the pharmaceutical industry participated?
Since 1992, I have directed research work on two large multi-institutional, multi-disciplinary research projects, both funded by the U.S. National Cancer Institute, an agency of the National Institutes of Health. As part of these projects, and after the signing of appropriate agreements, we have engaged with colleagues in two large pharmaceutical companies. These companies have provided access to their bioassays, and have provided advice on the pharmaceutical development of our best lead compounds.

Being editor of a major scientific publication, what are your considerations about the impact factor?
I have served as Editor in Chief of the Journal of Natural Products since 1994. In 1996, this became a co-publication of the American Chemical Society and the American Society of Pharmacognosy. As Editor, I realize the importance of the "Impact Factor" to many of our authors and readers, so we aim to maintain this at a high level. In order to this, the other journal editors and I try to select only the best papers on natural products for inclusion in our journal, and we adopt high editorial standards before a given paper is accepted for publication.

What are the current challenges for Chemistry of Natural Products?
At the moment, the natural products community is celebrating the 2015 Nobel Prize winners for Physiology or Medicine, which went to three pioneers who elucidated and tested new natural product compounds to treat patients with some deadly parasitic diseases and malaria. Therefore, while there is tremendous scientific interest in this area at present, it will be necessary for sustained governmental support in the future to foster new research and also to support the training of a new generation of natural product scientists. Also, it is important that new seminal discoveries continue to be made in the natural product area, in order to capture the attention of scientists in other disciplines.

What are your expectations for your coming visit to Brazil?
I will be able to exchange ideas with senior scientists from Brazil about how to develop our discipline of natural products further. In addition, I hope to stimulate younger scientists at the meeting I will be attending to continue their work on natural products topics. Brazil is a country endowed with a tremendous and unparalleled biodiversity, so it is really important that there be a very strong presence there in the study of potential useful compounds from natural sources. I am an Executive Committee member of the American Society of Pharmacognosy, so I would like to discuss this society with my Brazilian counterparts.

How to engage youth into seriously studying science?
Young people exhibit a considerable desire to do something for the overall benefit of society, and becoming a scientist is one way in which this can be accomplished. However, young people must learn the scientific method in order to perform scientific research, and this takes considerable patience. Unfortunately, there is a tendency for scientific experiments not always to work, so a student has to learn to overcome initial failure during their training. Therefore, students must commit to the scientific enterprise for the long-term.

What does it take to make a high quality scientist?
Several personality traits come to mind - a sense of curiosity, a desire to make a contribution in life, persistence, and a tendency to never be satisfied with previous accomplishments. These are in addition to having had a solid scientific training, preferably with one or more of the leaders in one's chosen field.

Artigos sugeridos

“Hernandulcin: an intensely sweet compound discovered by review of ancient literature”,  C.M. Compadre, K.M.  Pezzuto, A.D. Kinghorn, S.K. Kamath*, Science 1985, 227, 417-419.

“Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis”, E. Pisha, H. Chai, I.S. Lee, T.E. Chagwedera, N.R. Farnsworth, G.A. Cordell, C.W.W. Beecher, H.H.S. Fong, A.D. Kinghorn, D.M. Brown, M.C. Wani, M.E. Wall, T.J. Heijken, T.K. Das Gupta, J.M. Pezzuto*, Nature (Med.) 1995, 1, 1046-1051.

“Cancer chemopreventive activity of resveratrol, a natural product derived from grapes”, M. Jang, L. Cai, G.O. Udeani, K.V. Slowing-Barillas, C.F. Thomas, C.W.W. Beecher, H.H.S. Fong, N.R. Farnsworth, A.D. Kinghorn, R.G. Mehta, R.C. Moon, J.M. Pezzuto*, Science 1997, 275, 218-220.

“Silvestrol and episilvestrol, potential anticancer rocaglate derivatives from Aglaia silvestris”, B.Y. Hwang, B.N. Su, H. Chai, Q. Mi, L.B.S. Kardono, J.J. Afriastini, S. Riswan, B.D. Santarsiero, A.D. Mesecar, R. Wild, C.R. Fairchild, G.D. Vite, W.C. Rose, N.R. Farnsworth, G.A. Cordell, J.M. Pezzuto, S.M. Swanson, A.D. Kinghorn*, J. Org. Chem. 2004, 69, 3350-3358; ibid. 2004, 69, 6156.

“Sterols with antileishmanial activity isolated from the roots of Pentalinon andrieuxii”, L. Pan, C.M. Lezama-Davil, A.P. Isaac-Marquez, E.P. Calomeni, J.R. Fuchs, A.R. Satoskar, A.D. Kinghorn*, Phytochemistry 2012, 82, 128-135.

Saiba mais

Journal of Natural Products
http://pubs.acs.org/JNP

Comprehensive Cancer Center
http://cancer.osu.edu/

Página de Douglas Kinghorn na Faculdade de Farmácia de Ohio State
http://www.pharmacy.ohio-state.edu/faculty-staff/users/kinghorn4

A 39ª Reunião Anual da SBQ será no Centro de Convenções de Goiânia, de 30 de maio a 2 de junho de 2016.

Curta a página da RASBQ e acompanhe as novidades do evento! Convide também seus amigos. Juntos, faremos uma grande reunião anual!

Texto: Mario Henrique Viana (Assessor de imprensa da SBQ)