An Assessment of the Knowledge and Perceptions of Precision Medicine (PM) in the Rwandan Healthcare Setting.

INTRODUCTION: Precision medicine (PM) or personalized medicine is an innovative approach that aims to tailor disease prevention and treatment to consider the differences in people's genes, environments, and lifestyles. Although many efforts have been made to accelerate the universal adoption of PM, several challenges need to be addressed in order to advance PM in Africa. Therefore, our study aimed to establish baseline data on the knowledge and perceptions of the implementation of PM in the Rwandan healthcare setting. METHOD: A descriptive qualitative study was conducted in five hospitals offering diagnostics and oncology services to cancer patients in Rwanda. To understand the existing policies regarding PM implementation in the country, two additional institutions were surveyed: the Ministry of Health (MOH), which creates and sets policies for the overall vision of the health sector, and the Rwanda Biomedical Center (RBC), which coordinates the implementation of health sector policies in the country. The researchers conducted 32 key informant interviews and assessed the functionality of available PM equipment in the 5 selected health facilities. The data were thematically categorized and analyzed. RESULTS: The study revealed that PM is perceived as a complex and expensive program by most health managers and health providers. The most cited challenges to implementing PM included the following: the lack of policies and guidelines; the lack of supportive infrastructures and limited suppliers of required equipment and laboratory consumables; financial constraints; cultural, behavioral, and religious beliefs; and limited trained, motivated, and specialized healthcare providers. Regarding access to health services for cancer treatment, patients with health insurance pay 10% of their medical costs, which is still too expensive for Rwandans. CONCLUSION: The study participants highlighted the importance of PM to enhance healthcare delivery if the identified barriers are addressed. For instance, Rwandan health sector leadership might consider the creation of specialized oncology centers in all or some referral hospitals with all the necessary genomic equipment and trained staff to serve the needs of the country and implement a PM program.

Monitoring of Adverse Events in Recipients of the 2-Dose Ebola Vaccine Regimen of Ad26.ZEBOV Followed by MVA-BN-Filo in the UMURINZI Ebola Vaccination Campaign.

BACKGROUND: From 2019 to 2021, Rwandan residents of the border with the Democratic Republic of the Congo were offered the Ad26.ZEBOV (adenovirus type 26 vector vaccine encoding Ebola virus glycoprotein) and MVA-BN-Filo (modified vaccinia virus Ankara vector vaccine, encoding glycoproteins from Ebola, Sudan, Marburg, and nucleoprotein from Tai Forest viruses) Ebola vaccine regimen. METHODS: Nonpregnant persons aged ≥2 years were eligible. Unsolicited adverse events (UAEs) were reported through phone calls or visits, and serious adverse events (SAEs) were recorded per International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. RESULTS: Following Ad26.ZEBOV, UAEs were reported by 0.68% of 216 113 vaccinees and were more common in younger children (aged 2-8 years, 1.2%) compared with older children (aged 9-17 years, 0.4%) and adults (aged ≥18 years, 0.7%). Fever and headache were the most reported symptoms. All 17 SAEs related to vaccine were in children aged 2-8 years (10 postvaccination febrile convulsions ± gastroenteritis and 7 fever and/or gastroenteritis). The incidence of febrile seizures was 8 of 26 062 (0.031%) prior to initiation of routine acetaminophen in December 2020 and 2 of 15 897 (0.013%) thereafter. Nonobstetric SAEs were similar in males and females. All 20 deaths were unrelated to vaccination. Young girls and adult women with UAEs were less likely to receive the second dose than those without UAEs. Seven unrelated SAEs occurred in 203 267 MVA-BN-Filo recipients. CONCLUSIONS: Postvaccination febrile convulsions in young children were rare but not previously described after Ad26.ZEBOV and were reduced with routine acetaminophen. The regimen was otherwise safe and well-tolerated.

Emergence and clonal expansion of in vitro artemisinin-resistant Plasmodium falciparum kelch13 R561H mutant parasites in Rwanda.

Artemisinin resistance (delayed P. falciparum clearance following artemisinin-based combination therapy), is widespread across Southeast Asia but to date has not been reported in Africa1-4. Here we genotyped the P. falciparum K13 (Pfkelch13) propeller domain, mutations in which can mediate artemisinin resistance5,6, in pretreatment samples collected from recent dihydroarteminisin-piperaquine and artemether-lumefantrine efficacy trials in Rwanda7. While cure rates were >95% in both treatment arms, the Pfkelch13 R561H mutation was identified in 19 of 257 (7.4%) patients at Masaka. Phylogenetic analysis revealed the expansion of an indigenous R561H lineage. Gene editing confirmed that this mutation can drive artemisinin resistance in vitro. This study provides evidence for the de novo emergence of Pfkelch13-mediated artemisinin resistance in Rwanda, potentially compromising the continued success of antimalarial chemotherapy in Africa.

Single-Molecule Real-Time (SMRT) Full-Length RNA-Sequencing Reveals Novel and Distinct mRNA Isoforms in Human Bone Marrow Cell Subpopulations.

Hematopoietic cells are continuously replenished from progenitor cells that reside in the bone marrow. To evaluate molecular changes during this process, we analyzed the transcriptomes of freshly harvested human bone marrow progenitor (lineage-negative) and differentiated (lineage-positive) cells by single-molecule real-time (SMRT) full-length RNA-sequencing. This analysis revealed a ~5-fold higher number of transcript isoforms than previously detected and showed a distinct composition of individual transcript isoforms characteristic for bone marrow subpopulations. A detailed analysis of messenger RNA (mRNA) isoforms transcribed from the ANXA1 and EEF1A1 loci confirmed their distinct composition. The expression of proteins predicted from the transcriptome analysis was evaluated by mass spectrometry and validated previously unknown protein isoforms predicted e.g., for EEF1A1. These protein isoforms distinguished the lineage negative cell population from the lineage positive cell population. Finally, transcript isoforms expressed from paralogous gene loci (e.g., CFD, GATA2, HLA-A, B, and C) also distinguished cell subpopulations but were only detectable by full-length RNA sequencing. Thus, qualitatively distinct transcript isoforms from individual genomic loci separate bone marrow cell subpopulations indicating complex transcriptional regulation and protein isoform generation during hematopoiesis.

CHEK2 Germ Line Mutations are Lacking among Familial and Sporadic Breast Cancer Patients in Rwanda

Worldwide, breast cancer is the most frequent neoplasm and the second leading cause of cancer death among females. It dominates in both developed and developing countries and represents a major public health problem. The etiology is multifactorial and involves exogenous agents as well as endogenous factors. Although they account for only a small fraction of the breast cancer burden, mutations in the BRCA1 and BRCA2 genes are known to confer a high risk predisposition. Mutations in moderate/low-penetrance genes may also contribute to breast cancer risk. Previous studies have shown that mutations in the CHEK2 gene are involved in breast cancer susceptibility due to its impact on DNA repair processes and replication checkpoints. This study was conducted to evaluate the frequencies of three germline mutations in CHEK2 gene (c.1100delC, R145W and I157T) in breast cancers in Rwanda. Using direct DNA sequencing, we analyzed 41 breast cancer patients and 42 normal breast controls but could not detect any positives. CHEK2 mutations may be a rare event in Rwandan population and may only play a minor if an role in breast cancer predisposition among familial and sporadic cases.

Association between glutathione peroxidase 1 codon 198 variant and the occurrence of breast cancer in Rwanda.

BACKGROUND: Glutathione peroxidase 1 gene (GPX1) is one of the antioxidant enzyme that remove the reactive oxygen species in a continuous process. Since the identification of a well-characterized functional polymorphism named p.Pro198Leu (rs1050450 C>T) in GPX1 gene, abundant studies have evaluated the association between p.Pro198Leu polymorphism and tumor risk in diverse population. But, the available results related to breast cancer are conflicting and absent in Africa. The present case-control study was planned to assess the presence of GPX1 Pro198Leu polymorphism in Rwanda population to determine whether it is associated with the risk of developing breast cancer. METHODS: Genomic DNA from peripheral blood leukocytes of 41 patients with breast cancer and 42 healthy controls were enrolled and genotyped GPX1 Pro198Leu polymorphism by PCR amplification and DNA sequencing. RESULTS: No significant difference in the frequencies of Pro/Pro (49%) and Pro/Leu (51%) genotypes in cancer cases and in controls (50% each) were found. The allelic frequencies of Pro and Leu were 74% versus 26% and 75% versus 25% in breast cancer cases and controls respectively. No association was observed in allele frequencies of Pro and Leu, and familial history. Only an overall association of GPX1 Pro198Leu with grade of cancer (Pro/Leu vs. Pro/Pro: p = .0200) was detected. CONCLUSION: The result of this study suggested that GPX1 Pro198Leu polymorphism could not be a risk factor for breast cancer in Rwanda. However, large-scale studies on the effect of this polymorphism on the factors disturbing the redox homeostasis are needed for conclusive understanding.

Detection of human papillomavirus DNA in tumors from Rwandese breast cancer patients.

BACKGROUND: During the last decades, a great interest was given to viral etiology of breast cancer. Indeed, due to recent technical improvements and some encouraging new results, it has been a resurgence of interest in the possibility that a substantial proportion of human breast cancers may be caused by viral infections. High-risk genotypes of human papillomavirus (HPV) have been found in breast cancer cases. In the present study, we aimed to assess the presence of HPV DNA in breast cancer cases from Rwanda and to evaluate the association between HPV infection and clinico-pathological features. METHODS: Therefore, a total of 47 archived formalin-fixed paraffin-embedded biopsies were collected and complete information was recorded. HPV detection and genotyping were done by PCR amplification and DNA sequencing. RESULTS: Overall, HPV DNA was found in 46.81% of cases, HPV16 being the most prevalent subtype (77.27%) followed by HPV33 (13.64%) and HPV31 (9.09%). Comparison of HPV with clinico-pathological features showed no significant difference between HPV infection and breast localization, histological subtype, clinical stage, tumor grade, and intrinsic molecular subtypes. CONCLUSIONS: These findings provide evidence of high prevalence of high-risk HPV in Rwandese patients with breast cancer and suggest that high-risk HPV infections could be a risk factor associated with human breast cancer development.

Association of p53 Codon 72 Polymorphism with Breast Cancer in a Rwandese Population.

BACKGROUND AND AIMS: A common polymorphism in the tumor suppressor gene p53 at codon 72 has been suggested to play a role in the development of a number of cancers. This polymorphism has been studied in many populations worldwide, with conflicting results. The present study was planned to assess the association of p53 codon 72 polymorphism with breast cancer development in a Rwandese population. METHODS: In this study, the polymorphism was examined by allele-specific PCR analysis in 40 patients with breast cancer and 39 healthy controls. RESULTS: The heterozygous genotype Pro/Arg prevailed in both breast cancer patients and controls, and was present in 80% (32/40) and 92.3% (36/39) of cases, respectively. No statistically significant association was observed between p53 codon 72 polymorphism and breast cancer risk. Distribution of p53 genotypes was also studied according to familial history, tumor grade, and clinical stage, and results clearly showed no statistically significant difference. CONCLUSION: These results suggest that p53 codon 72 polymorphism could not be assessed as a risk factor marker for predisposition to breast cancer in Rwanda. However, further studies using larger sample sizes are needed to provide more conclusive results and to investigate other genetic mutations affecting the activity of p53.