CD79B
Overview
CD79B mutations significantly contribute to the pathogenesis of DLBCL by enhancing BCR signaling and promoting tumor survival. These mutations, especially when co-occurring with MYD88 mutations, define a unique molecular subtype.1 This has clinical and therapeutic implications as it may contribute sensitivity to BTK inhibitors. In an inducible mouse model of MYD88-driven DLBCL, CD79B mutations did not accelerate lymphomagenesis but demonstrated an increased sensitivity to pharmacological BTK inhibition.2 In a retrospective analysis, younger patients with MCD DLBCL that were treated with ibrutinib had significantly better outcomes.wilsonEffectIbrutinibRCHOP2021b? The most common hotspot mutation in CD79B is at the tyrosine residue 196 (Y196). This and other common mutations primarily occur in the immunoreceptor tyrosine-based activation motif (ITAM) domain and prevent the negative regulatory feedback provided by Lyn kinase thereby enhancing BCR signaling.3
History
Relevance tier by entity
| Entity | Tier | Description |
|---|---|---|
| 2 | relevance in BL not firmly established4 | |
| 1 | high-confidence DLBCL gene5 | |
| 2 | relevance in FL not firmly established |
Mutation incidence in large patient cohorts (GAMBL reanalysis)
| Entity | source | frequency (%) |
|---|---|---|
| BL | GAMBL genomes+capture | 1.39 |
| BL | Thomas cohort | 0.00 |
| BL | Panea cohort | 4.00 |
| DLBCL | GAMBL genomes | 9.94 |
| DLBCL | Schmitz cohort | 14.89 |
| DLBCL | Reddy cohort | 8.31 |
| DLBCL | Chapuy cohort | 15.38 |
| FL | GAMBL genomes | 2.77 |
Mutation pattern and selective pressure estimates
| Entity | aSHM | Significant selection | dN/dS (missense) | dN/dS (nonsense) |
|---|---|---|---|---|
| BL | No | No | 0.000 | 0.000 |
| DLBCL | No | Yes | 16.616 | 41.932 |
| FL | No | No | 10.310 | 0.000 |
CD79B Hotspots
Mutations at Y196 enhance B-cell receptor (BCR) signaling by preventing the negative regulatory feedback provided by Lyn kinase, a feedback inhibitor of BCR signaling. This results in continuous activation of the NF-κB pathway, promoting tumor cell survival and proliferation.4
| Chromosome | Coordinate (hg19) | ref>alt | HGVSp |
|---|---|---|---|
| chr17 | 62007234 | C>G | A150P |
| chr17 | 62007234 | C>T | A150T |
| chr17 | 62007233 | G>A | A150V |
| chr17 | 62007140 | A>G | L181P |
| chr17 | 62007129 | C>T | X184_splice |
| chr17 | 62006798 | T>A | Y197F |
| chr17 | 62006798 | T>C | Y197C |
| chr17 | 62006799 | A>C | Y197D |
| chr17 | 62006799 | A>G | Y197H |
| chr17 | 62006798 | T>G | Y197S |
| chr17 | 62006795 | T>C | E198G |
| chr17 | 62006680 | A>G | L200P |
| chr17 | 62006680 | A>C | L200R |
| chr17 | 62006680 | A>T | L200Q |
| chr17 | 62006603 | G>A | H226Y |
| chr17 | 62006603 | G>T | H226N |
View coding variants in ProteinPaint hg19 or hg38
View all variants in GenomePaint hg19 or hg38


