Ethiopian Cancer Research Articles

Detection of High- and Low-Risk HPV DNA in Archived Breast Carcinoma Tissues from Ethiopian Women.

Background Human papilloma virus (HPV) is involved in the development of cancer of the cervix, mouth and throat, anus, penis, vulva, or vagina, but it has not been much considered as a cause of breast cancer. Recently, a number of investigations have linked breast cancer to viral infections. High-risk HPV types, predominantly HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59, are established as carcinogens in humans. In this study we aimed to detect 19 high-risk and 9 low-risk HPVs from archived breast tumor tissue among Ethiopian women. Methods In this study, 75 breast cancer patients from Tikur Anbassa Specialized Hospital in Addis Ababa (Ethiopia) were included. HPV detection and genotyping were done using the novel Anyplex™ II HPV28 Detection Assay at the Orebro University Hospital, Sweden. The Anyplex™ II PCR System detects 19 high-risk HPV types (16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 69, 73, and 82) and 9 low-risk HPV types (6, 11, 40, 42, 43, 44, 54, 61, and 70). IHC for p16 was done using an automated system, the Dako Autostainer Link. Results Out of the 75 valid tests, two were found to be positive (2.7%) for HPV. One of the cases was positive for the high-risk HPV16 genotype while the other was positive both for the high-risk HPV39 and the low-risk HPV6. The cell cycle protein p16 was highly expressed in the case positive for the high-risk HPV16, but it was not expressed in the case positive for HPV39. Conclusion The prevalence of HPV is low in Ethiopian breast cancer patients, but the role played by HPV in breast carcinogenesis among Ethiopian breast cancer patients cannot be commented based on these observations.

Abstract B062: Genetic driving factors of aggressive Ethiopian breast cancer

Abstract In Ethiopia, a breast cancer diagnosis is associated with a prognosis significantly worse than that of Europe and the US. Further, patients presenting with breast cancer in Ethiopia are far younger, on average, and patients are typically diagnosed at very late stages, relative to breast cancer patients of European descent. The standard of care for Ethiopian breast cancer patients is radiotherapy and broad-spectrum chemotherapy, which is also the case for US patients with triple-negative breast cancer (TNBC). However, the limited publications that do exist on Ethiopian tumors, and our own preliminary data, suggest that a large proportion of these patients have hormone-positive (ER+) breast cancer. This is surprising 1) given the aggressive nature of the disease, 2) given that African Americans with breast cancer frequently have TNBC, and 3) given the non-hormone targeting treatment these patients are receiving. There is a paucity of information on the molecular and genetic driving factors driving Ethiopian breast cancer, and this is critically hindering treatment strategies for these patients. The Black Lion Hospital in Addis Ababa treats patients from all over the country, and so we have partnered with Dr. Daniel Seifu at the Black Lion Hospital to gather more information about this deadly disease. In this project, we have brought together expertise across multiple institutions to collect tumor specimens, subtype the specimens, and perform DNA and RNAseq on these tumors. We used the TruSeq Exome kit (Illumina) to sequence matched normal and tumor tissue from 3 patients from a small pilot collection. We identified mutations in 127 genes across all three patients, unique to the tumor tissue. We found mutations in BARD1, BRCA2, and BRIP1, and each patient had a mutation in a different spot in the BRCA2 gene. Second, we compared our data to a list of mutations found for inherited breast and ovarian cancer (1), and found mutations in BRCA2, BRIP1, and MSH2, but not the other 7 panel genes. Finally, we compared our initial data set to the Personalized Cancer Mutation Panel (covering 737 mutational hotspots on 45 genes, across many different cancers (2), and found mutations in 3 of these genes: ALK, APC, and HNF1A, but not in the other 42 genes in their panel. At the same time, all these mutations we identified were specific to the tumor tissue and were not found in the matched healthy tissue we analyzed. At this conference we will discuss these results and our analysis from the additional collected samples as the project continues.