HUNK

Hormonally upregulated neu-associated kinase (HUNK) is a serine/threonine protein kinase within the SNF1/AMPK family, where it regulates cellular survival, proliferation, autophagy, and trafficking-related processes through kinase-dependent signaling mechanisms^[1][2]. HUNK is activated downstream of oncogenic HER2/neu, EGFR, and Akt signaling and functions as an important effector that supports tumor cell survival in breast cancer models^[2][3]. Mechanistically, HUNK promotes autophagy through phosphorylation of the autophagy regulator Rubicon, thereby supporting cytoprotective pathways associated with HER2-positive breast cancer progression and therapeutic resistance^[4][5]. In disease models, genetic deletion, knockdown, or pharmacological inhibition of HUNK suppresses mammary tumorigenesis, impairs metastatic phenotypes, and enhances sensitivity to HER2-targeted therapies, highlighting its value as an experimental target in resistant breast cancer settings^[2][3][5]. HUNK also regulates metastatic signaling through phosphorylation of EGFR, contributing to migration, invasion, and metastatic progression in breast cancer models^[3]. Compared with other AMPK-family kinases that primarily function as cellular energy sensors, HUNK has been most strongly linked to oncogenic survival pathways, autophagy regulation, and metastatic signaling in mammary tumor biology^[1][2]. For experimental applications, the multi-kinase inhibitor staurosporine was identified as an inhibitor of HUNK activity, while more recent studies have reported the development of selective HUNK inhibitors that suppress HUNK-dependent phosphorylation events and tumorigenic phenotypes in HER2-positive breast cancer models^[5][6].