Fibulin-2 inhibitors encompass a class of compounds that regulate the expression or function of the extracellular matrix protein fibulin-2. These inhibitors do not bind directly to fibulin-2 but affect its synthesis, deposition, or stability in the extracellular matrix through the modulation of various signaling pathways. For example, SB431542 is a selective inhibitor of TGF-β signaling. Since TGF-β has been implicated in the regulation of fibulin-2 expression, the inhibition of this pathway by SB431542 leads to a decrease in fibulin-2 production. Erlotinib, an EGFR inhibitor, and U0126, a MEK inhibitor, act upon the EGFR and MEK/ERK pathways, respectively, both of which are pathways known to regulate the expression of a multitude of genes, including fibulin-2.
Moreover, these compounds influence the post-translational modifications and interactions of fibulin-2 with other extracellular matrix components and cells. For instance, 17-AAG, an HSP90 inhibitor, may disrupt the proper folding of fibulin-2, leading to its potential degradation or malfunction. Similarly, metalloproteinase inhibitors like Marimastat prevent the proteolytic cleavage of fibulin-2, thereby preserving its integrity in the extracellular matrix. The actions of these inhibitors are highly specific to certain cellular processes and signaling pathways that either directly or indirectly impact the homeostasis of fibulin-2 within the extracellular space. Through these diverse mechanisms, each chemical exerts its influence on fibulin-2 expression and function, highlighting the complex regulatory network that controls extracellular matrix proteins.