Human betaretrovirus (HBRV), homologous to mouse mammary tumor virus (MMTV), and human breast cancer: a significant epidemiological association
摘要
Breast cancer is the most commonly diagnosed cancer globally. The potential role of oncogenic viruses, particularly Human Betaretrovirus (HBRV, formerly MMTV-LV/HMTV), in the pathogenesis of breast cancer has been a subject of research for decades. However, studies investigating this association have produced conflicting results. This systematic review and meta-analysis aim to assess the prevalence of HBRV in breast cancer cases and evaluate its potential association with breast cancer.
MethodsA systematic literature search was conducted in MEDLINE, Web of Science, Scopus, and EMBASE following PRISMA guidelines. Studies assessing HBRV prevalence in breast cancer patients and case-control studies investigating its association with breast cancer risk were included. The Newcastle-Ottawa Scale (NOS) was used to evaluate study quality, and meta-analysis was performed using RevMan 5.1. Heterogeneity was assessed using the I² statistic, and subgroup analyses were conducted based on detection methods, sample types, and geographic regions.
ResultsThe literature search identified a total of 45 studies that were deemed suitable for inclusion in the systematic review. 26 studies were used in the subsequent meta-analysis. The initial meta-analysis revealed a significant association between HBRV and breast cancer (OR = 4.92, 95% CI: 4.00–6.04, p < 0.00001) but exhibited high heterogeneity (I² = 82%). After excluding an outlier, heterogeneity was significantly reduced (I² = 22%), with a revised OR of 11.95 (95% CI: 8.78–16.25, p < 0.00001 ). Subgroup analysis demonstrated variation in detection methods, with Nested PCR (OR = 19.15) and Frozen tissue samples (OR = 18.00) showing the strongest associations. Geographic analysis indicated the highest odds in North America (OR = 24.75), followed by Europe (OR = 15.02).
ConclusionThis meta-analysis suggests strong epidemiological evidence supporting an association between HBRV infection and human breast cancer, and is consistent with a possible etiological role. However, variability in study methodologies and geographic differences warrant further investigation through standardized, large-scale studies to confirm these findings and explore potential mechanisms of viral oncogenesis in breast cancer.