Homeobox protein Hox-A9 mRNA (HOXA9 mRNA)

Homeobox A9 (HOXA9) mRNA is a critical transcript encoding a homeodomain-containing transcription factor that serves as a master regulator of hematopoiesis and embryonic development (UniProt P31269, PubMed 31515550). In healthy physiology, HOXA9 expression is high in hematopoietic stem cells and is progressively silenced during myeloid differentiation; however, its pathological overexpression is a hallmark of aggressive leukemias, particularly those involving KMT2A (MLL) rearrangements or NPM1 mutations (PubMed 28814371, 38219018). Because the HOXA9 protein is a transcription factor and historically considered undruggable, therapeutic efforts focus on reducing the levels of its mRNA or disrupting its essential protein-protein interactions (PubMed 38219018). The most clinically advanced strategy involves Menin-KMT2A inhibitors, such as Revumenib and Ziftomenib, which prevent the transcriptional machinery from activating the HOXA9 gene, thereby leading to a rapid decline in HOXA9 mRNA levels and inducing the differentiation of leukemic blasts (PubMed 38219018). Additionally, experimental approaches such as antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs) are being explored to directly target the mRNA for degradation (PubMed 30622285). Monitoring HOXA9 mRNA levels is a vital biomarker for assessing disease prognosis and the efficacy of targeted therapies in myeloid malignancies (PubMed 38219018).

Other names

HOX1HOX1.7HOX1GABD-B homeobox family member mRNAHomeobox A9 transcript

Transcriptional downregulation via Menin-KMT2A inhibition; RNA interference; Antisense-mediated degradation