Risk factor for breast cancer development under exposure to bovine leukemia virus in Colombian women: A case-control study

Abstract

Viruses have been implicated in cancer development in both humans and animals. The role of viruses in cancer is typically to initiate cellular transformation through cellular DNA damage, although specific mechanisms remain unknown. Silent and long-term viral infections need to be present, in order to initiate cancer disease. In efforts to establish a causative role of viruses, first is needed to demonstrate the strength and consistency of associations in different populations. The aim of this study was to determine the association of bovine leukemia virus (BLV), a causative agent of leukemia in cattle, with breast cancer and its biomarkers used as prognosis of the severity of the disease (Ki67, HER2, hormonal receptors) in Colombian women. An unmatched, observational case–control study was conducted among women undergoing breast surgery between 2016–2018. Malignant samples (n = 75) were considered as cases and benign samples (n = 83) as controls. Nested-liquid PCR, in-situ PCR and immunohistochemistry were used for viral detection in blood and breast tissues. For the risk assessment, only BLV positive samples from breast tissues were included in the analysis. BLV was higher in cases group (61.3%) compared with controls (48.2%), with a statistically significant association between the virus and breast cancer in the unconditional logistic regression (adjusted-OR = 2.450,95%CI:1.088–5.517, p = 0.031). In this study, BLV was found in both blood and breast tissues of participants and an association between breast cancer and the virus was confirmed in Colombia, as an intermediate risk factor.

Bovine Leukaemia Virus: Current Epidemiological Circumstance and Future Prospective

“…BLV proviral DNA has been found in milk and meat products, which has focused attention on the possible transmission of the disease to humans via such foodstuffs [20]. Several reports show that BLV may harm humans through a possible link between BLV infection and the development of breast cancer in women, as well as other haematopoietic neoplastic diseases [21][22][23][24][25]. Comparison of data indicates a surprising geographical correlation between incidence of breast cancer and the consumption of bovine meat and milk.…”

Bovine leukemia virus detection in humans: A systematic review and meta-analysis

“…One study analyzed two samples from the same person, seeking to correlate the results of BLV detection in peripheral blood and fresh breast tissue. The authors found that BLV was detected both in blood and breast tissues with a correlation of 94% in the positive samples of the study ( Olaya-Galan et al., 2021 ; Corredor-Figueroa et al., 2021 ) ( Table 3 ).…”

“…(2021) 27 Prevalence of bovine leukosis virus in water buffaloes in West-central Colombia 2021 Revista Mexicana De Ciencias Pecuarias Colombia Flórez et al. (2021) 28 Risk factor for breast cancer development under exposure to bovine leukemia virus in Colombian women: A case-control study 2021 PLoS One Colombia Olaya-Galan et al. (2021) 29 Virus de la leucosis bovina (VLB) y evidencias de su potencial zoonótico 2021 Doctoral thesis Colombia Olaya-Galán (2021) 30 Virus de la leucosis bovina: evaluación de la presencia del provirus en sangre humana y analisis in silico de los receptores celulares involucrados en su interacción 2021 Master's Thesis Colombia Velandia Álvarez (2021) 31 Bovine leukemia viral DNA found on human breast tissue is genetically related to the cattle virus 2021 One Health Brazil Canova et al.…”

Risk factors associated with enzootic bovine leukosis in Boyacá and Cundinamarca municipalities, Colombia

“…BLV infection leads to decreased immune function, making animals more vulnerable to other diseases, which could shorten their productive life ( Benitez et al , 2020 ). On the other hand, could be a potential zoonotic disease, Ma et al (2021) and Olaya-Galan et al (2021) reported that BLV has been found in the blood and mammary tissues of women with breast cancer, and an association between this and the virus was confirmed in Colombia, as an intermediate risk factor; however, the link between BLV and human breast cancer is somewhat controversial. Moreover, there is no specific treatment for the disease or commercial vaccine that allows the prevention of the disease ( Bulla-Castañeda et al , 2018 ).…”