Risk, Incidence, and Mortality of Breast Cancer in Primary Sjögren's Syndrome: A Systematic Review and Meta-Analysis

Healthy lifestyles, systemic inflammation and breast cancer risk: a mediation analysis

BACKGROUND

Despite the known association between healthy lifestyles and reduced risk of breast cancer, it remains unclear whether systemic inflammation, as a consequence of unhealthy lifestyles, may mediate the association.

METHODS

A cohort study of 259,435 female participants in the UK Biobank was conducted to estimate hazard ratio (HR) for breast cancer according to 9 inflammation markers using Cox regression models. We further estimated the percentage of total association between healthy lifestyle index (HLI) and breast cancer that is mediated by these inflammation markers.

RESULTS

During 2,738,705 person-years of follow-up, 8,889 cases of breast cancer were diagnosed among 259,435 women in the UK Biobank cohort. Higher level of C-reactive protein (CRP), systemic immune-inflammation index (SII), CRP-to-albumin Ratio (CAR), CRP-to-lymphocyte Ratio (CLR), monocyte-to-HDL-c ratio (MHR), and neutrophil-to-HDL-c ratio (NHR) were associated with increased breast cancer risk, while a higher lymphocyte-to-monocyte ratio (LMR) was associated with a lower risk. The inverse association between HLI and breast cancer was weakly mediated by CRP (8.5%), SII (1.71%), CAR (8.66%), CLR (6.91%), MHR (6.27%), and NHR (7.33%). When considering individual lifestyle factors, CRP and CAR each mediated 16.58% and 17.20%, respectively, of the associations between diet score and breast cancer risk, while the proportion mediated for physical activity and breast cancer were 12.13% and 11.48%, respectively. Furthermore, MHR was found to mediate 13.84% and 12.01% of the associations between BMI, waist circumference, and breast cancer.

CONCLUSION

The association of HLI and breast cancer is weakly mediated by the level of inflammation, particularly by CRP and CAR. Systemic inflammatory status may be an intermediate in the biological pathway of breast cancer development.

Risk analysis of breast cancer and breast fibrocystic change in female primary Sjögren's syndrome patients

Sjögren's syndrome is an autoimmune disease with the chronic inflammation of glandular tissues, typically salivary and lacrimal glands. Since mammary tissue shares the glandular structure, Sjögren's syndrome may also target mammary tissue to cause breast diseases. We therefore determined whether primary Sjögren's syndrome (pSS) is associated with the increased risk of breast cancer (BC) and breast fibrocystic change (FC). Total 282 female patients with pSS were recruited from a medical center in Taiwan, and patients' medical records were reviewed to identify BC and ultrasonographic breast FC. The prevalence, incidence and risk factors for BC and breast FC in pSS patients were determined, and the risk factors for these breast diseases were subsequently analyzed. Our results showed that pSS patients had the increased prevalence and incidence of BC, and high anti-SSA(Ro) antibody titers were found to be associated with the increased risk of BC. Breast FC was also found highly prevalent in these patients. Comorbidity analysis as risk factor for BC in pSS patients showed diabetes mellitus was strongly associated with the increased risk of BC (odds ratio = 10.4, P = .0006), whereas breast FC was inversely associated with the risk of BC (odds ratio = 0.077 P = .0158). These data indicated that pSS is association with the increased risk of BC and with the high prevalence of ultrasonographic breast FC. Our results also suggest that, in pSS patients, the high anti-SSA(Ro) antibody titers and diabetes mellitus confer the increased risk of BC, whereas the absence of ultrasonographic breast FC predicts the higher risk of BC.

The interconnected roles of TRIM21/Ro52 in systemic lupus erythematosus, primary Sjögren's syndrome, cancers, and cancer metabolism

Protein tripartite motif-containing 21 (TRIM21/Ro52), an E3 ubiquitin ligase, is an essential regulator of innate immunity, and its dysregulation is closely associated with the development of autoimmune diseases, predominantly systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS). TRIM21 /Ro52 also features anti-cancer and carcinogenic functions according to different malignancies. The interconnected role of TRIM21/Ro52 in regulating autoimmunity and cell metabolism in autoimmune diseases and malignancies is implicated. In this review, we summarize current findings on how TRIM21/Ro52 affects inflammation and tumorigenesis, and investigate the relationship between TRIM21/Ro52 expression and the formation of lymphoma and breast cancer in SLE and pSS populations.