HOXB9 and neoplasm: Therefore, the regulation of HOXB9 is crucial in the cooperated oncogenic loops.12 Our data suggested that HOXB9 hypermethylation may be a novel tumor cellular state that is useful for precise categorization of tumor heterogeneity in the study of intrinsic EGFR-TKI resistance via off-target effects such as redundant or compensating signaling.