Differentiation signals induce APOBEC3A expression via GRHL3 in squamous epithelia and squamous cell carcinoma

Two APOBEC (apolipoprotein-B mRNA editing enzyme catalytic polypeptide-like) DNA cytosine deaminase enzymes (APOBEC3A and APOBEC3B) generate somatic mutations in cancer, driving tumour development and drug resistance. Here we used single cell RNA sequencing to study APOBEC3A and APOBEC3B expression in healthy and malignant mucosal epithelia, validating key observations with immunohistochemistry, spatial transcriptomics and functional experiments. Whereas APOBEC3B is expressed in keratinocytes entering mitosis, we show that APOBEC3A expression is confined largely to terminally differentiating cells and requires Grainyhead-like transcription factor 3 (GRHL3). Thus, in normal tissue, neither deaminase appears to be expressed at high levels during DNA replication, the cell cycle stage associated with APOBEC-mediated mutagenesis. In contrast, we show that in squamous cell carcinoma tissues, there is expansion of GRHL3 expression and activity to a subset of cells undergoing DNA replication and concomitant extension of APOBEC3A expression to proliferating cells. These findings indicate a mechanism for acquisition of APOBEC3A mutagenic activity in tumours.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - year:2024

Enthalten in:

Research square - (2024) vom: 04. März

Sprache:

Englisch

Beteiligte Personen:

Smith, Nicola J [VerfasserIn]
Reddin, Ian [VerfasserIn]
Policelli, Paige [VerfasserIn]
Oh, Sunwoo [VerfasserIn]
Zainal, Nur [VerfasserIn]
Howes, Emma [VerfasserIn]
Jenkins, Benjamin [VerfasserIn]
Tracy, Ian [VerfasserIn]
Edmond, Mark [VerfasserIn]
Sharpe, Benjamin [VerfasserIn]
Amendra, Damian [VerfasserIn]
Zheng, Ke [VerfasserIn]
Egawa, Nagayasu [VerfasserIn]
Doorbar, John [VerfasserIn]
Rao, Anjali [VerfasserIn]
Mahadevan, Sangeetha [VerfasserIn]
Carpenter, Michael A [VerfasserIn]
Harris, Reuben S [VerfasserIn]
Ali, Simak [VerfasserIn]
Hanley, Christopher [VerfasserIn]
Buisson, Rémi [VerfasserIn]
King, Emma [VerfasserIn]
Thomas, Gareth J [VerfasserIn]
Fenton, Tim R [VerfasserIn]

Links:

Volltext

Themen:

APOBEC3A
Cancer mutagenesis
Differentiation
GRHL3
HNSCC
Keratinocyte
Preprint

Anmerkungen:

Date Revised 25.03.2024

published: Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.21203/rs.3.rs-3997426/v1

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369861345