Cadherin-2 (N-Cadherin) and Gap junction alpha-1 protein (Connexin 43) interaction (CDH2/GJA1)

The interaction between bone marrow stromal cells (BMSCs) and hematopoietic stem cells (HSCs) within the bone marrow niche is mediated significantly by Cadherin-2 (N-Cadherin) and Gap junction alpha-1 protein (Connexin 43) (Zhang et al., Nature, 2003; Cancelas et al., Blood, 2000). Cadherin-2 facilitates the physical anchoring of HSCs to the endosteal niche, which is crucial for maintaining stem cell quiescence and protecting them from environmental stressors (Hosokawa et al., Cell Stem Cell, 2010). Gap junction alpha-1 protein forms functional gap junctions that allow for direct metabolic and ionic signaling between the stromal microenvironment and hematopoietic cells, influencing cell cycle progression and survival (Taniguchi et al., Blood, 2012). In hematological malignancies, such as acute myeloid leukemia (AML), these interactions are often hijacked to protect leukemic stem cells from chemotherapy-induced apoptosis, contributing to drug resistance and relapse (Khoury et al., Leukemia, 2011). Therapeutic strategies targeting these molecules, such as the N-cadherin antagonist ADH-1 (Exherin) or Connexin 43 modulators like αCT1, aim to disrupt this protective niche and sensitize malignant cells to treatment (Perotti et al., J Clin Oncol, 2007; Grek et al., Cancers, 2014). However, because these proteins are widely expressed in other tissues—particularly Connexin 43 in the myocardium—systemic inhibition presents significant safety challenges, including potential cardiotoxicity (Smyth et al., J Clin Invest, 2010).

Other names

N-CadherinConnexin 43CDH2GJA1Cx43BMSC-HSC niche interactionBone marrow stromal cell-hematopoietic stem cell interface

Disruption of N-cadherin-mediated adhesion and Connexin 43-mediated gap junctional communication between stromal cells and hematopoietic stem cells to sensitize malignant cells to therapy.