Latest News Archive

Please select Category, Year, and then Month to display items
Categories
UFS News Media Release Research
Years
2019 2020 2021 2022 2023 2024 2025
Months
January February March April May June July August September October November December
Previous Archive
04 December 2024 | Story André Damons | Photo André Damons
Breast Cancer Research 2024
The research team consist of Dr Beynon Abrahams (left), Viwe Fokazi, MMed.Sci student, and PhD student Songezo Vazi.

In an effort to better understand chemotherapeutic treatment response in triple negative breast cancer (TNBC) – known as an aggressive cancer with high recurrence and high mortality rate in breast cancer patients – researchers from the University of the Free State (UFS) developed a drug-resistant TNBC spheroid model that is physiologically more accurate in displaying the complexities involved in drug-resistance development.

Dr Beynon Abrahams, Lecturer in the Department of Basic Medical Sciences within the UFS Faculty of Health Sciences, says breast cancer remains the most frequently diagnosed cancer in women. It is also the most debilitating type of cancer responsible for the highest cancer mortality rates in women. Though various subtypes of breast cancer exist, TNBC is one that is of particular interest to his research team.

“TNBC is one of the most difficult cancer types to treat, due to lack of treatment targets. This often leads to treatment failure in TNBC patients, with drug resistance being a common occurrence, contributing to high death rates. TNBC is classified based on its lack of expression of common receptors such as the estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2, which are commonly expressed in other cancer subtypes.

“Characteristically, TNBC is known as an aggressive cancer with high metastatic potential (spreading of cancer), resulting in a poor prognosis for these patients. The current prescribed therapies for TNBC, entails multidrug combination systemic therapy including chemotherapeutic agents such as doxorubicin and cisplatin as adjuvant therapy. However, despite these therapeutic interventions, drug resistance is a common occurrence,” says Dr Abrahams.

The best available preclinical cell-based models should be used

For effective drug treatments to be developed for TNBC therapeutics, he continues, the best available disease models should be used to not only improve our understanding of the disease physiology and its numerous mechanisms involved in chemotherapeutic resistance development but also to provide accurate results when determining how safe and effective newly developed drugs are, before they may be considered for further development and testing on humans.

According to him, in preclinical cancer research the conventional methods employed to study disease mechanisms, drug action and drug resistance is ineffective. Firstly, the traditionally used preclinical 2-dimensional (2-D) cell culture models do not accurately recapitulate the architectural biology observed in vivo, second, the drug responses assessed in these models may provide inaccurate results and limit its translational potential, explains Dr Abrahams. Thus, more advanced cell-based models such as 3-dimensional (3-D) spheroids and organoids to name a few, should be considered as alternatives.

The UFS research team, in collaboration with the Centre of Excellence for Pharmaceutical Sciences (Pharmacen™) at the North-West University (NWU), recently took the undertaking to establish two triple negative breast cancer 3-D spheroid models, using the clinostat rotating bioreactor ClinoStar™ system, designed by CelVivo in Denmark. The project is funded by the National Research Foundation.

The ClinoStar™ system promotes the self-aggregation of single cells, and natural formation of 3-D spheroids, through slow rotation within a cell growth chamber known as an incubator. There are various techniques and methods available to develop spheroids and organoids, however the ClinoStar™ systems allow for the development of metabolically stable spheroids, over a longer period of time, as opposed to other methods. It also eliminates the sheer-stress conditions that are normally encountered when using 2-D cell culture models.

“We successfully established one chemotherapeutic-sensitive triple negative breast cancer spheroid model and one novel cisplatin-resistant triple negative breast cancer spheroid model. The chemo-sensitive TNBC spheroid model was evaluated for responsiveness against two clinically used chemotherapeutic agents, doxorubicin and cisplatin. We suggest that this model may be useful to screen novel compounds including traditionally used phytomedicinal material for anticancer activity.

“In our second model, the cisplatin-resistant TNBC spheroid model was also exposed to cisplatin and doxorubicin and demonstrated a resistant response in terms of growth and viability. We believe that this model may be useful to further explore drug resistance mechanisms and may also be used as a tool to assess the drug reversal potential of novel compounds. The value and impact of these models lies in that they may offer predictive drug responses that are closer to that observed in in vivo (animals), as opposed to 2-D cell cultures. This however needs to be assessed. We are currently in the process to fully characterise these spheroids models.”

Aim of the research

Dr Abrahams explains their research aims to merge the gap between conventionally used 2-D cell models and in vivo models, by providing a model that is physiologically more accurate in mimicking the in vivo conditions and complex pathways associated with drug resistance, which is otherwise not observed or accurately expressed in 2D models. “Although our research is preclinical and considered fundamental basic research, the translational potential of our spheroid models may provide options for exploring and testing alternative drugs that may be considered for translational research,” Dr Abrahams says.

Characterising other advanced cell-based cancer models

The team is currently in the process of further characterising the TNBC spheroid model based on protein and genetic expression profiles to elucidate potential therapeutic biomarkers for drug treatment as well as screening various phytomedicinal plants, to assess their antiproliferative and drug-resistance reversal potential. In addition, the researchers recently commenced a new research project that aims to develop a drug-resistant prostate cancer spheroid model using the Clinostar™ system with their collaborators at the NWU.

Advanced cell-based model research is still relatively ‘new’ in South Africa and Africa, compared to the global North. As a result, says Dr Abrahams, their NWU collaborators together with other stakeholders, initiated the establishment of the Society for Advanced Cell Culture Modelling for Africa (SACCMA) in 2021, which aims to develop the fields of advanced cell modelling, three-dimensional (3D) cell cultures, 3D bioprinting and stem cell research, in Africa. Our current inter-departmental  collaboration include researchers from the Pharmacology department, but we hope to build and expand our collaboration network in the near future.

News Archive

Inaugural lecture: Prof. Phillipe Burger
2007-11-26

 

Attending the lecture were, from the left: Prof. Tienie Crous (Dean of the Faculty of Economic and Management Sciences at the UFS), Prof. Phillipe Burger (Departmental Chairperson of the Department of Economics at the UFS), and Prof. Frederick Fourie (Rector and Vice-Chancellor of the UFS).
Photo: Stephen Collet

 
A summary of an inaugural lecture presented by Prof. Phillipe Burger on the topic: “The ups and downs of the South African Economy: Rough seas or smooth sailing?”

South African business cycle shows reduction in volatility

Better monetary policy and improvements in the financial sector that place less liquidity constraints on individuals is one of the main reasons for the reduction in the volatility of the South African economy. The improvement in access to the financial sector also enables individuals to manage their debt better.

These are some of the findings in an analysis on the volatility of the South African business cycle done by Prof. Philippe Burger, Departmental Chairperson of the University of the Free State’s (UFS) Department of Economics.

Prof. Burger delivered his inaugural lecture last night (22 November 2007) on the Main Campus in Bloemfontein on the topic “The ups and downs of the South African Economy: Rough seas or smooth sailing?”

In his lecture, Prof. Burger emphasised a few key aspects of the South African business cycle and indicated how it changed during the periods 1960-1976, 1976-1994 en 1994-2006.

With the Gross Domestic Product (GDP) as an indicator of the business cycle, the analysis identified the variables that showed the highest correlation with the GDP. During the periods 1976-1994 and 1994-2006, these included durable consumption, manufacturing investment, private sector investment, as well as investment in machinery and non-residential buildings. Other variables that also show a high correlation with the GDP are imports, non-durable consumption, investment in the financial services sector, investment by general government, as well as investment in residential buildings.

Prof. Burger’s analysis also shows that changes in durable consumption, investment in the manufacturing sector, investment in the private sector, as well as investment in non-residential buildings preceded changes in the GDP. If changes in a variable such as durable consumption precede changes in the GDP, it is an indication that durable consumption is one of the drivers of the business cycle. The up or down swing of durable consumption may, in other words, just as well contribute to an up or down swing in the business cycle.

A surprising finding of the analysis is the particularly strong role durable consumption has played in the business cycle since 1994. This finding is especially surprising due to the fact that durable consumption only constitutes about 12% of the total household consumption.

A further surprising finding is the particularly small role exports have been playing since 1960 as a driver of the business cycle. In South Africa it is still generally accepted that exports are one of the most important drivers of the business cycle. It is generally accepted that, should the business cycles of South Africa’s most important trade partners show an upward phase; these partners will purchase more from South Africa. This increase in exports will contribute to the South African economy moving upward. Prof. Burger’s analyses shows, however, that exports have generally never fulfil this role.

Over and above the identification of the drivers of the South African business cycle, Prof. Burger’s analysis also investigated the volatility of the business cycle.

When the periods 1976-1994 and 1994-2006 are compared, the analysis shows that the volatility of the business cycle has reduced since 1994 with more than half. The reduction in volatility can be traced to the reduction in the volatility of household consumption (especially durables and services), as well as a reduction in the volatility of investment in machinery, non-residential buildings and transport equipment. The last three coincide with the general reduction in the volatility of investment in the manufacturing sector. Investment in sectors such as electricity and transport (not to be confused with investment in transport equipment by various sectors) which are strongly dominated by the government, did not contribute to the decrease in volatility.

In his analysis, Prof. Burger supplies reasons for the reduction in volatility. One of the explanations is the reduction in the shocks affecting the economy – especially in the South African context. Another explanation is the application of an improved monetary policy by the South African Reserve Bank since the mid 1990’s. A third explanation is the better access to liquidity and credit since the mid 1990’s, which enables the better management of household finance and the absorption of financial shocks.

A further reason which contributed to the reduction in volatility in countries such as the United States of America’s business cycle is better inventory management. While the volatility of inventory in South Africa has also reduced there is, according to Prof. Burger, little proof that better inventory management contributed to the reduction in volatility of the GDP.

Economic and Management Sciences

Education

Health Sciences

The Humanities

Law

Natural and Agricultural Sciences

Theology and Religion

Open Distance Learning

Business School

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept