MYBL1
Overview
MYBL1 (MYB proto-oncogene like 1, also known as A-MYB) is a transcription factor closely related to MYB. In salivary gland adenoid cystic carcinoma (AdCC), MYBL1 forms oncogenic fusions with NFIB analogous to the canonical MYB::NFIB fusion, defining a distinct molecular subset of AdCC.
Alterations observed in the corpus
- Canonical MYBL1::NFIB fusion in 9/88 (10%) of sinonasal adenoid cystic carcinomas; represents the MYBL1-driven subset, which is morphologically indistinguishable from MYB::NFIB tumors PMID:24418857
- Recurrent intra- and inter-chromosomal rearrangements in 35% of t(6;9)-negative ACCs in a 102-tumor cohort; fusions include MYBL1-NFIB t(8;9), MYBL1-YTHDF3, and truncations — all deleting the C-terminal negative regulatory domain and driving MYBL1 overexpression; associated with better outcome than MYB alterations (P=0.010) PMID:26631609
- Recurrent MYBL1–NFIB fusion in 2/25 ACC tumors (HN 333 PT, HN 320 PT), which uniquely lacked MYB expression, supporting a mutually exclusive MYB/MYBL1 alteration model in ACC PMID:26862087
Cancer types (linked)
- AdCC (Adenoid Cystic Carcinoma, sinonasal): MYBL1::NFIB fusion in 10% of cases; morphologically and clinically similar to MYB::NFIB-driven AdCC PMID:24418857
Co-occurrence and mutual exclusivity
- MYBL1::NFIB and MYB::NFIB fusions are generally mutually exclusive, with each defining a distinct molecular subset of AdCC PMID:24418857
Therapeutic relevance
- No targeted therapy established; MYBL1 fusion-positive status may have diagnostic utility for confirming AdCC in fusion-negative cases.
Open questions
- Whether MYBL1::NFIB carries the same prognostic significance as MYB::NFIB remains to be determined.
Sources
This page was processed by crosslinker on 2026-05-14. - PMID:26631609
This page was processed by crosslinker on 2026-05-14. - PMID:26862087
This page was processed by wiki-cli on 2026-05-14.