Kdr, also known as Kinase insert Domain containing Receptor or Vascular Endothelial Growth Factor Receptor (VEGFR-2), is involved in endothelial dysfunction and plays a role in many biological processes. It is associated with pathways related to angiogenesis, as seen in its influence on tumor neovascularization in colorectal cancer [5]. In the context of insects, kdr-type resistance is due to mutations in the para-homologous sodium channel gene, causing insensitivity of the nervous system to pyrethroids and DDT [3].

In houseflies, kdr-type alleles such as kdr (L1014F), kdr-his (L1014H), super-kdr (M918T + L1014F), type N (D600N + M918T + L1014F), and 1B (T929I + L1014F) have led to resistance against pyrethroids. High levels of resistance are associated with the L1014F mutation in North America, Europe, and Asia [1]. In Aedes aegypti mosquitoes in Brazil, kdr mutations (Val1016Ile and Phe1534Cys) have rapidly spread and increased in frequency, and a 'kdr index' was introduced to analyze spatial patterns [6]. In Aedes albopictus, kdr mutations associated with resistance to DDT and pyrethroids were first evidenced in 2011 and have since been reported in various regions worldwide [7]. In house flies in Abu Dhabi, UAE, the kdr allele was found in most sampling locations, and in addition to the L1014F mutation, L1014H and T929I mutations were detected [8].

In conclusion, Kdr has diverse functions. In insects, kdr-related mutations are crucial in conferring resistance to insecticides, which has implications for pest control strategies. In human-related research, Kdr is associated with various diseases. Its role in endothelial dysfunction, angiogenesis, and its influence on disease severity and drug-induced hepatotoxicity, as well as its potential as a predictor for immunotherapy in pan-cancer, highlight its importance in understanding disease mechanisms and developing treatment strategies [1,2,4,5,9].