SMAD4 and colorectal carcinoma: Based on these data, we conclude that CRC‐associated downregulation of VPS4B does not reflect its own tumor suppressor function but rather represents a passenger alteration co‐existing with concomitant loss of the neighboring 18q‐located tumor suppressors, such as DCC, SMAD2, and SMAD4 (Nguyen & Duong, 2018).