Telomerase is perceived as an immortality enzyme that might provide longevity to cells and whole organisms. Importantly, it is generally inactive in most somatic cells of healthy, adult men. Consequently, its substrates, i.e. telomeres, get shorter in most human cells with time. Noteworthy, cell life limitation due to telomere attrition during cell divisions, may not be as bad as it looks since longer cell life means longer exposition to harmful factors. Consequently, telomere length (attrition rate) becomes a factor that is responsible for inducing the signaling that leads to the elimination of cells that lived long enough to acquire severe damage. It seems that telomere length that depends on many different factors (including telomerase activity but also genetic factors, a hormonal profile that reflects sex, etc.) might become a useful marker of aging and exposition to stress. Thus in the current paper, we review the factors that affect telomere length in human cells focusing on sex that all together with different environmental and hormonal regulations as well as parental aspect affect telomere attrition rate. We also raise some limitations in the assessment of telomere length that hinders a trustworthy meta-analysis that might lead to acknowledgment of the real value of this parameter.

Breast cancer is the most frequently diagnosed malignant tumor in women. Due to the high heterogeneity and multiplicity of histological subtypes within this type of cancer, the expression of breast cancer markers is very diverse. Therefore, a biomarker with high sensitivity and specificity would be extremely important for the correct diagnosis and prognosis assessment in breast cancer patients. Mammaglobin A seems to be such a biomarker. Overexpression of this protein is closely related with carcinogenesis in the mammary gland and is observed in up to 80% of cases of the malignant breast cancers. According to many reports, it is postulated that mammaglobin A may be a promising tool in the diagnostics of cancers but also a prognostic, predictive and therapeutic factor. The information contained in this publication presents the current state of knowledge about the structure of mammaglobin A, its function, role in the tumorigenesis and the use of this protein as a diagnostic marker and therapeutic target in breast cancer.