# Autoantibodies targeting DNA repair found in pediatric cancer blood samples

- Published: 2026-11-06 16:11 UTC
- Section: Life & Health › Medicine
- Tags: pediatric cancer autoantibodies, Frontiers in Immunology, DNA repair proteins, cell penetrating IgG, RAD52, MGMT
- URL: https://realtech.media/news/rt-e815fb44de9a809ac419d6d8_autoantibodies_targeting_dna/

**Researchers analyzed sera from 375 individuals and detected cell-penetrating autoantibodies years before pediatric cancer onset.**

![Autoantibodies targeting DNA repair found in pediatric cancer blood samples](https://sgzwpqqelzmajkcubgkl.supabase.co/storage/v1/object/public/rt-media/2026/11/0fa9e647036a1534.webp)
*Science & Vie*

An international research team led by the University of Bergen evaluated blood samples to investigate the immunological origins of pediatric tumors. According to a study published in Frontiers in Immunology, scientists screened sera from 375 patients and healthy controls using high-density native proteome arrays [1]. The analysis revealed an enrichment of specific IgG autoantibodies targeting proteins involved in DNA repair, primarily in children and adolescents aged 2 to 19.

Investigators tested sera from cohorts diagnosed with acute leukemia or sarcoma, alongside prospective samples from British long-term cohorts, ALSPAC and Born in Bradford. Among 59 monitored participants, half of whom developed cancer before age 30, antibodies targeting DNA repair enzymes appeared up to nine years before clinical diagnosis [1]. Children with these autoantibodies exhibited an eightfold higher risk of developing malignancies. The key targets identified include repair proteins RAD52, UNG, and MGMT, whose corresponding genes showed no direct mutations.

## Intracellular transport of serum antibodies

Because DNA repair operates inside the cell, researchers evaluated whether these circulating immunoglobulins could access intracellular machinery. Laboratory assays on live cells demonstrated that serum IgG molecules penetrate intact cell membranes [1]. The internalization was notably observed when cells halted growth to prepare for division.

Upon entering live cells, the antibodies exhibited a distinctive subcellular localization pattern. In 52% of the tested pediatric cases, IgG molecules accumulated within the TIGER compartment, an intracellular structure associated with the synthesis of regulatory proteins [1].

## Prospects for early screening assays

Researchers note that the verified penetration into living cells points to a functional inhibition of genomic maintenance without direct alterations to the genetic code. While this mechanism offers a potential explanation for tumor emergence in tissues with low mutation loads, the study remains limited by the small prospective sample size [1].

Next steps outlined by the authors involve measuring the direct impairment of DNA repair kinetics by these antibodies, cloning the producing B-cells, and testing pathological effects in mouse models. No clinical diagnostic tests are currently available for screening.

## Sources

1. [Frontiers in Immunology](https://doi.org/10.3389/fimmu.2026.1911932)
2. [Science & Vie](https://www.science-et-vie.com/corps-et-sante/cancers-infantiles-des-chercheurs-decouvrent-la-piste-inattendue-des-anticorps-capables-de-penetrer-dans-les-cellules-265580.html)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-e815fb44de9a809ac419d6d8_autoantibodies_targeting_dna/