Induction of Trop-2 expression through the binding of galectin-3 to MUC1.

Both mucin 1 (MUC1) and trophoblast cell surface antigen 2 (Trop-2) are overexpressed in various epithelial tumor cells, and their high expression is correlated with a poor prognosis. Both proteins were expressed in a human breast cancer cell line, MCF-7 cells, but neither was in a human colon cancer cell line, HCT116 cells. When MUC1 cDNA was introduced into HCT116 cells (HCT116/MUC1), expression of Trop-2 was induced. Reciprocally, treatment of MCF-7 cells with MUC1 siRNA reduced the level of Trop-2. Mithramycin A, an inhibitor of specificity protein 1 (Sp1) transcription factor, effectively inhibited the expression of Trop-2. Consistently, treatment with Sp1 siRNA reduced the expression of Trop-2. To reveal the relationship between MUC1 and Sp1, coimmunoprecipitation assays were performed. Sp1 was coimmunoprecipitated with MUC1 and the level of coimmunoprecipitated Sp1 increased in relation to the level of induced Trop-2. It is known that galectin-3 is an endogenous ligand of MUC1. Binding of galectin-3 to MUC1 elevated the recruitment of Sp1 to MUC1, and knockdown of galectin-3 reduced the level of Trop-2. These results suggest that the binding of galectin-3 to MUC1 enhances the recruitment of Sp1, leading to promotion of the transcription of Trop-2.

Navigating Hurdles: A Review of the Obstacles Facing the Development of the Pandemic Treaty.

INTRODUCTION: The emergence of the COVID-19 pandemic has served as a call for enhanced global cooperation and a more robust pandemic preparedness and response framework. As a result of this pressing demand, dialogues were initiated to establish a pandemic treaty designed to foster a synchronized global strategy for addressing forthcoming health emergencies. In this review, we discussed the main obstacles to this treaty. RESULTS: Among several challenges facing the pandemic treaty, we highlighted (1) global cooperation and political will, (2) equity in access to resources and treatments, (3) sustainable financing, (4) compliance and enforcement mechanisms, (5) sovereignty concerns, and (6) data sharing and transparency. CONCLUSION: Navigating the hurdles facing the development of the pandemic treaty requires concerted efforts, diplomatic finesse, and a shared commitment to global solidarity. Addressing challenges in global cooperation, equitable access, transparency, compliance, financing, and sovereignty is essential for forging a comprehensive and effective framework for pandemic preparedness and response on the global stage.