The Sunday Mail
Youth Buzz
Tanyaradzwa Rusike
YOUNG scientist Shingirai Chiwambutsa recently flew the Zimbabwean flag high in Dubai, where she was accorded a special accolade at the Merck Foundation Africa Research Summit — MARS 2022 for her work on breast cancer treatment.
She was a winner in the Best African Women Researchers MARS Award 2022 for her “outstanding research abstract related to cancer”.
The Merck Foundation is an international organisation dedicated to the improvement of the health and wellbeing of people through science and technology.
Titled “Effects of genetic polymorphisms of drug metabolising enzymes and co-medications on tamoxifen in black breast cancer patients of African ancestry”, Ms Chiwambutsa’s research is aimed at developing models that predict potential treatment failure and establish the dose required for results in optimal treatment of breast cancer patients.
The 33-year-old scientist claims African female patients treated with the drug tamoxifen do not fully benefit from the medication, resulting in the recurrence of the cancer.
Tamoxifen is a hormone therapy for breast cancer in both women and men, which lowers the risk of early breast cancer coming back after surgery.
The hormone therapy, Ms Chiwambutsa said, needs to be converted into active metabolite endoxifen, an important chemical that inhibits breast cancer growth, for the medicine to work effectively.
She said most women in Africa are, however, failing to transform tamoxifen into endoxifen, a problem that prompted her research.
“More than 50 percent of breast cancer patients are failing to transform tamoxifen into endoxifen despite taking the recommended daily dose as prescribed by their doctors. No wonder my research focus is on understanding why some of these women with breast cancer who are being treated with tamoxifen do not get better,” she said.
Ms Chiwambutsa said the research focuses on African women because, traditionally, studies had referenced white and Asian women.
“In our research, we sought to understand the unique African genetic variants, determine the levels of the active chemical endoxifen and determine if we could find answers that might help improve treatment outcomes for African women with breast cancer being treated with tamoxifen.
“The aim is to leverage on the knowledge and evidence for potential use in precision medicine and personalised tamoxifen therapy for breast cancer patients . . . Clinical pharmacokinetics guidelines for use of tamoxifen have been published for Caucasian and Asian populations but not for people of African ancestry, who may require differing dosing requirements because of their genetic makeup.
“To date, few studies have reported pharmacokinetic models incorporating tamoxifen in predicting endoxifen exposure, hence our model will be used as a guide for tamoxifen dosing to improve treatment outcomes.”
The young scientist, who grew up with a passion for sciences, said she believes in evidence-based decision making.
“I have always had a passion to do sciences. My first degree was purely Mathematics, but when I was doing it, I discovered that Mathematics is not only limited to those complicated theorems and proofs but can be applied in medicine, disease modelling, pharmacology, epidemiology, finance, engineering and agriculture,” she said.
“My undergraduate project was centred on disease modelling, whereby I developed a mathematical model for the transmission dynamics of Hepatitis B in a population.
“As I was writing the project, I further developed my interests in biostatistics, epidemiology and health sciences.”
Ms Chiwambutsa — who is currently working with the Sydney Brenner Institute of Molecular Bioscience in collaboration with the African Institute of Biomedical Science and Technology — urged young people who are passionate about sciences to be unflinching in their pursuits.
“Science is an amazing journey; embrace it. Be a risk taker or present your opinion, even when you are the only woman in a meeting. Stick with your dreams; don’t give up because it’s not always easy. You might face negativity but you have to keep going. Scientific progress is built on failure as each failure teaches us to move forward; it’s called failing forward,” she said.
Bred in Harare, she attended Zuvarabuda Primary School in Glen Norah and Highfield High School. She studied for her first degree at the National University of Science and Technology, while she completed her master’s degree at the University of Zimbabwe.
Currently, she is a PhD candidate at the University of Witwatersrand in Johannesburg in the Human Genetics Division.
Her study focuses on “Tamoxifen pharmacokinetic and pharmacogenetics modelling”.
Twitter: @tdrusike
