A minimal promoter region of Kit gene recapitulates mast cell differentiation in development, aging and inflammation.

To follow mast cells (MCs) distribution during aging and inflammation, we characterized two transgenic mouse models in which the EGFP expression is controlled by 9 kb or 12 kb of Kit gene promoter, defined as p18 and p70, respectively. We detected EGFP-positive cells in the serosal surfaces of the peritoneum, pleuras and pericardium, mucosal cavities, and connective tissue of almost all organs including gonads of p70, but not of p18 mice. By FACS and immunofluorescence for FcεR1, Kit and ß7-integrin, we found that these EGFP positive cells were MCs. In non-inflammatory conditions, a higher percentage of EGFP positive cells was found in juvenile with respect to adult serosal surfaces, but no differences between males and females at both developmental ages. We found, however, a striking difference in developing gonads, with low numbers of EGFP positive cells in fetal ovaries compared to age matched testes. Under inflammatory conditions caused by high fat diet (HFD), mice showed an increase in serosal EGFP positve cells. Altogether our results identify a regulatory region of the Kit gene, activated in MCs and that directing EGFP expression, can be employed to trace this immune cell type throughout the organism and in different animal conditions.

Impact of age and gender on glioblastoma onset, progression, and management.

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, while its frequency in pediatric patients is 10-15%. For this reason, age is considered one of the major risk factors for the development of GBM, as it correlates with cellular aging phenomena involving glial cells and favoring the process of tumor transformation. Gender differences have been also identified, as the incidence of GBM is higher in males than in females, coupled with a worse outcome. In this review, we analyze age- and gender- dependent differences in GBM onset, mutational landscape, clinical manifestations, and survival, according to the literature of the last 20 years, focusing on the major risk factors involved in tumor development and on the mutations and gene alterations most frequently found in adult vs young patients and in males vs females. We then highlight the impact of age and gender on clinical manifestations and tumor localization and their involvement in the time of diagnosis and in determining the tumor prognostic value.