Rational design, optimization, and biological evaluation of novel α-Phosphonopropionic acids as covalent inhibitors of Rab geranylgeranyl transferase

EMT activates exocytotic Rabs to coordinate invasion and immunosuppression in lung cancer

Epithelial-to-mesenchymal transition (EMT) underlies immunosuppression, drug resistance, and metastasis in epithelial malignancies. However, the way in which EMT orchestrates disparate biological processes remains unclear. Here, we identify an EMT-activated vesicular trafficking network that coordinates promigratory focal adhesion dynamics with an immunosuppressive secretory program in lung adenocarcinoma (LUAD). The EMT-activating transcription factor ZEB1 drives exocytotic vesicular trafficking by relieving Rab6A, Rab8A, and guanine nucleotide exchange factors from miR-148a-dependent silencing, thereby facilitating MMP14-dependent focal adhesion turnover in LUAD cells and autotaxin-mediated CD8+ T cell exhaustion, indicating that cell-intrinsic and extrinsic processes are linked through a microRNA that coordinates vesicular trafficking networks. Blockade of ZEB1-dependent secretion reactivates antitumor immunity and negates resistance to PD-L1 immune checkpoint blockade, an important clinical problem in LUAD. Thus, EMT activates exocytotic Rabs to drive a secretory program that promotes invasion and immunosuppression in LUAD.

Protein Prenyltransferases and Their Inhibitors: Structural and Functional Characterization

Protein prenylation is a post-translational modification controlling the localization, activity, and protein–protein interactions of small GTPases, including the Ras superfamily. This covalent attachment of either a farnesyl (15 carbon) or a geranylgeranyl (20 carbon) isoprenoid group is catalyzed by four prenyltransferases, namely farnesyltransferase (FTase), geranylgeranyltransferase type I (GGTase-I), Rab geranylgeranyltransferase (GGTase-II), and recently discovered geranylgeranyltransferase type III (GGTase-III). Blocking small GTPase activity, namely inhibiting prenyltransferases, has been proposed as a potential disease treatment method. Inhibitors of prenyltransferase have resulted in substantial therapeutic benefits in various diseases, such as cancer, neurological disorders, and viral and parasitic infections. In this review, we overview the structure of FTase, GGTase-I, GGTase-II, and GGTase-III and summarize the current status of research on their inhibitors.