Mast cells - key players of digestive tumors associated angiogenesis.

INTRODUCTION: Mast cells (MCs) are immune cells derived from hematopoietic cluster of differentiation (CD)34+ and CD117+ precursors that complete their maturation in peripheral tissues such as the connective and mucosal layers, perivascular and perineural regions, and secondary lymphoid organs, where they play essential roles in regulating immune responses. The MC's dual role as both an effector and regulator of angiogenesis makes it a valuable indicator of tumor aggressiveness and a potential therapeutic target in digestive malignancies. MATERIALS AND METHODS: 41 cases of digestive tumors with gastric, pancreatic and colorectal origins and their corresponding liver metastasis were evaluated by morphological and immunohistochemical techniques. The effects of Sodium Cromoglycate (Cromolyn) applied to a xenograft of cells derived from a liver metastasis of colorectal origin with a desmoplastic histological growth pattern, applied to chorioallantoic membrane (CAM) were analyzed. CD34 and mast cell tryptase (MCT) were used as primary antibodies. RESULTS: A statistically significant correlation was noticed between mast cell density (MCD) outside the metastasis area and microvascular density (MVD) in the metastasis area with pancreatic origin (p=0.023). A statistically significant correlation was noted with a p-value of 0.046 for the desmoplastic histological growth pattern, between MCD in the metastatic area and the degree of differentiation. After therapy with Cromolyn, increased MVD and the absence of positive MCT were noticed in the xenograft. CONCLUSIONS: The analysis of MCD demonstrated marked variability depending on tumor type, differentiation, and histological growth pattern. Targeting MC activation could represent an adjuvant of anti-angiogenic therapy in metastatic digestive cancers.