Faculty of Health Sciences (ETDs)
Permanent URI for this communityhttps://hdl.handle.net/10539/37925
Browse
Search Results
Item Impact of Cannabidiol and Tamoxifen treatment on cell death and cell survival in breast cancer in vitro(University of the Witwatersrand, Johannesburg, 2024) Mahasha, Mahlatse Fortunate; Augustine, TanyaThe main non-psychotropic component of Cannabis sativa, Cannabidiol (CBD), alleviates breast cancer treatment-associated side effects but its effects with standard therapy remain unclear. In breast cancer, CBD has been shown to exhibit anti-cancer properties by inducing apoptosis and pro-death autophagy. This study aimed to investigate the effects of combined CBD and Tamoxifen treatment on metabolism, cell death, and cell survival mechanisms in luminal-A breast cancer cell lines MCF7 and T47D. The CBD concentration relative to IC50 was established by testing a range of CBD concentrations: 5 μM, 7 μM, and 10 μM, at 24 h, 48 h, and 72 h using the neutral red cell viability assay. The scratch assay was used to determine the effects of the concentrations on migratory capacity. Two models of treatment were used, single-dose treatment (model 1) and daily-replacement treatment (model 2), and appropriate controls were included. Treatment with 2 μM Tamoxifen and 5 μM CBD for 48 h was determined to be the optimal treatment condition. The MTT assay was performed, and the absorbance ratio indicative of cell proliferation was calculated. The ability of the cells to metabolize the drug components was examined through an assessment of CYP450 reductase (CPR) enzyme activity. The mRNA and protein expression levels of three autophagic markers; BECN1, LC3B, and p62, were investigated using qPCR and immunocytochemistry, respectively. Friedman’s Anova (p<0.05) and Kruskal Wallis (p<0.05) post hoc tests were used to statistically analyse the data. Combined CBD and Tamoxifen treatment showed the greatest decrease in the proliferation of MCF7 cells and T47D cells compared with all other treatments across both treatment models, with the daily- replacement treatment model (model 2) showing more efficacy thus suggesting that combined treatment may inhibit cell proliferation. CYP450 enzyme reductase activity was higher in T47D cells compared with MCF7 cells in both treatment models suggesting increased metabolic activity and susceptibility to combined treatment. However, in the daily replacement model, MCF7 cell CPR activity could not be ascertained, suggesting either prodrug availability or reduced CPR activity. Further analysis is required in this regard. For immunolocalization, optimization was conducted in late 2021 and all three antibodies showed clear and expected immunolocalization but when the experiments were repeated early 2022, immunofluorescence was reduced (P62 and BECN1), with LC3B not detectable. P62 and BECN1 were expressed in both MCF7 and T47D cells across both treatment models although BECN1 expression was not sufficient to be quantified and assessed statistically. LC3B protein levels could not be accurately quantified irrespective of the treatment model used. Low amounts of target mRNA in MCF7 cells resulted in undetermined Cq values of LC3B, P62 and BECN1 genes across both treatment models. In T47D cells, Cq values of target genes were determined across both treatment models and the fold change in gene expression indicated that combined CBD and Tamoxifen treatment effectively upregulates target genes albeit not significantly (LC3B, P62 and BECN1) with the single-dose treatment model (model 1) compared with the daily replacement model. Both the immunofluorescence and qPCR experiments would be required to be repeated to ensure conclusive results. The findings of this study nevertheless indicate that combined CBD and Tamoxifen treatment may inhibit tumour growth, but tumour cells may be able to evade cell death pathways resulting in tumour cell survivalItem An audit of clinically triaged women at low risk for breast cancer presenting to the Helen Joseph Mammography Unit, Johannesburg(2024) Naidu, Lavandhra R.BACKGROUND: The Helen Joseph Hospital (HJH) Breast Clinic utilises a clinical triage system to stratify patients based on their risk of breast cancer into high, medium, or low risk profiles. This allows for timeous imaging and subsequent management of those patients at increased risk for breast cancer. OBJECTIVES: The primary objective was to determine the cancer detection rate (CDR). The secondary objective was to correlate biopsy results with the Breast Imaging – Reporting and Data System (BI-RADS) risk-assessment. METHODS: A retrospective audit of the patients at low risk for breast cancer who were referred to the Breast Imaging Unit (BIU) in 2019 at HJH. Patients were clinically assessed as low risk based on a triage form (Figure 4) and were identified using the imaging files stored in the BIU. Results were recorded on Microsoft Excel and calculated as per the American College of Radiology guidelines. RESULTS: The total population sample consisted of 398 patients. Two patients were characterised as BI-RADS 4 and underwent breast biopsies. One patient was diagnosed with histologically proven breast cancer. The CDR was 2.51% and the most representative age group was the 60 to 69 years one. The most common BI-RADS breast density assessment was group B while the most common BI-RADS risk assessment was category 2. CONCLUSION: Amongst the low-risk population, both the CDR and spectrum of disease was comparable that of a screening population. This may be due to the use of a triage system prior to imaging, as well as an increase in clinical awareness of breast cancer within a tertiary institution.Item Risk factors for breast cancer among women in Ekurhuleni Metropolitan Municipality, Gauteng Province of South Africa, 2017–2020: a case-control study(2024) Mashele, Sizeka AubreyBackground: Breast cancer (BC) is the most common cancer among women in South Africa (SA). In 2020, the age-standardized incidence rate (ASIR) and the age-standardized mortality rate (ASMR) were 52.6 and 16.0 per 100 000, respectively. There is a paucity of evidence on the risk factors for BC among women of all population groups in SA. The goal of this study was to determine the risk factors for BC, calculate the ASIR as well as explore epidemiological changes in BC among women in Ekurhuleni Metropolitan Municipality, Gauteng Province, SA. Methods: An unmatched case-control study was conducted from 1 January 2017 to 31 December 2020 using secondary data extracted from the Ekurhuleni Population-Based Cancer Registry (EPBCR). Unconditional multivariable logistic regression analysis was carried out using the adjusted odds ratio (aOR). The variables race, employment, HIV, smoking and alcohol statuses were included in the multivariable logistic regression model while the model was adjusted for age. In addition to risk factor analyses, we calculated the ASIR for BC in women using the Statistics South Africa population estimates as a denominator and the Segi-World Standard Population (WSP) for standardization. The joinpoint regression program was used to estimate the average annual per cent change (AAPC) for the four years (2017–2020). Results: A total of 3068 (2217 cases and 851 controls) participants were enrolled in the study. The mean age (±SD) in years of the participants was 55.2 (±15.2). The White population group, being self-employed and Human Immunodeficiency Virus (HIV) -positive status was significantly associated with reduced odds of BC development among women. Women who were HIV-positive were 61% less likely to have BC than women who were HIV-negative (aOR 0.39; 95%CI: 0.27‒ 0.57). White women were 75% less likely to have BC than women of other races (aOR 0.35; 95%CI: 0.29‒0.43). Self-employed women were 59% less likely to have BC than women who v were formally employed (aOR 0.41; 95%CI: 0.18‒0.97). The ASIR for BC among all women in 2017 was 42.33 (95%CI: 39.25–45.59) and 23.39 (95%CI: 21.10–25.86) per 100 000 in 2020. White women had the highest incidence rate of BC throughout the study period (55.47 (95%CI: 47.57–65.08) in 2017, 69.70 (95%CI: 60.77–79.74) in 2018, 35.51 (95%CI: 29.29–42.85) in 2019 and 37.12 (95%CI: 30.74–44.62) in 2020) compared to other population groups. No significant reduction in BC incidence rate was observed among all women throughout the study period with an exception of Black women, whereby a significant reduction in BC incidence rate was observed between 2017 and 2020 with an AAPC of -23.5% (p=0.017) Conclusion: In this study, the White population group, being self-employed and HIV-positive had lower odds of BC and thus necessitate more in-depth studies using primary data to effectively explore the risk factors of BC among women in SA settings. There was no significant change in AAPC except for Black women, this indicates disparities in screening uptake among population groups, and as such, there is a need to strengthen BC preventive strategies. There is a need for public health awareness to scale up BC screening uptake as well as the promotion of early detection through targeted awareness campaigns.Item Breast cancer survival to 5 years among young (<40 years) women in the sub-saharan African breast cancer-disparities in outcome (ABC-DO) cohort study(2024) Abioye, Oyepeju F.Introduction: Breast cancer remains a key global health challenge, accounting for most prevalent cause of cancer-related deaths worldwide. The impact of age at diagnosis on breast cancer survival has not been extensively investigated within the African context. Therefore, this study’s objectives were to estimate the breast cancer survival time among women 40 years) women in the ABC-DO Cohort Study in SSA. Methods: Secondary data analysis of breast cancer patients from the multi-country ABC-DO Prospective Cohort Study of 5 African countries was carried out. Baseline characteristics of study participants were summarized using descriptive statistics. Kaplan Meier curves were generated to evaluate breast cancer survival time by age group “<40 years, 40-64 years, 65+ years”. With the aid of Cox Multivariate Regression Modelling, factors correlated with a 5-year survival differential between younger and older women were investigated and Hazard Ratios were calculated adjusting for confounders. Results: This study had a total number of 2158 participants, 462 (21.41%) were <40 years at diagnosis, 1314 were between 40-64years (60.89%), while 382 patients were 65 years and above (17.70%). A total of 1211 deaths were recorded at 5 years. The total time at risk and incidence rate at 5 years was 6086.73 person years and 33 per 100 women respectively. The lowest overall survival at 5 years was found among women <40 years (33.46%; CI = 0.28-0.38), followed by women aged 65 years+ (37.63%; CI = 0.32-0.42), and highest overall survival was among women in the 40-64 years age group (42.66%; CI=0.39-0.45). For each country, the 5-year probability of survival was higher among women aged 40-64 compared to women under 40. On Cox multivariate analysis, a 20% rise in mortality was reported among women < 40 years (aHR 1.20; 95% CI= 1.03- 1.36) compared to women between 40-64 years in the final model, at p<0.05. The variables significantly associated with 5-year survival differential between younger and older women were: HIV status, Residence, and Stage at Diagnosis. Conclusion: This study reports that breast cancer survival among women in sub-Saharan Africa is age-specific, with lower 5-year overall and country-specific survival among women < 40 years in comparison to older women. Factors associated with lower survival include stage at diagnosis, HIV status, and area of residence. Young women (<40 years) in SSA remain at risk of increased mortality from breast cancer, hence there is an urgent need for targeted strategies to achieve a more favorable stage at diagnosis and improved survival in this populace.