Combinatory effect of BRCA1 and HERC2 expression on outcome in advanced non-small-cell lung cancer.

Abstract

BACKGROUND:

BRCA1 is a main component of homologous recombination and induces resistance to platinum in preclinical models. It has been studied as a potential predictive marker in lung cancer. Several proteins modulate the function of BRCA1. The E3 ubiquitin ligase HERC2 facilitates the assembly of the RNF8-UBC13 complex to recruit BRCA1 to DNA damage sites. The combined analysis of multiple components of the pathway leading to the recruitment of BRCA1 at DNA damage sites has the potentiality to improve the BRCA1 predictive model.

METHODS:

We retrospectively analyzed 71 paraffin-embedded tumor samples from advanced non-small-cell lung cancer patients treated with first-line platinum based chemotherapy and measured the mRNA expression levels of BRCA1, RNF8, UBC13 and HERC2 using real-time PCR. The mRNA expression was categorized using median value as cut-off point.

RESULTS:

The median progression-free survival of all 71 patients was 7.2 months whereas the median overall survival of the study population was 10.7 months. Among patients with low BRCA1 expression, the median PFS was 7.4 months in the presence of low HERC2 levels and 5.9 months for patients expressing high HERC2 levels (p = 0.01). The median OS was 15.3 months for patients expressing low levels of both genes and 7.4 months for those with low BRCA1 but high HERC2 (p = 0.008). The multivariate analysis showed that among patients with Eastern Cooperative Oncology Group performance status 0-1, the combined low expression of both BRCA1 and HERC2 clearly reduced the risk of progression (p = 0.03) and of death (p = 0.004).

CONCLUSIONS:

These findings confirm the potentiality of integrated DNA repair components analysis in predicting the sensitivity to platinum in lung cancer. The study indicates a predictive role for HERC2 mRNA expression and paves the way for further refinement of the BRCA1 predictive model.

• Authors: Laura Bonanno, Carlota Costa, Margarita Majem, Jose-Javier Sanchez, Ignacio Rodriguez, Ana Gimenez-Capitan, Miquel Angel Molina-Vila, Alain Vergnenegre, Bartomeu Massuti, Adolfo Favaretto, Massimo Rugge, Cinta Pallares, Miquel Taron, Rafael Rosell
• Journal: BMC cancer (BMC Cancer) Vol. 16 Pg. 312 (05 14 2016) ISSN: 1471-2407 [Electronic] England
• PMID: 27179511 (Publication Type: Journal Article)

Chemical References

• Antineoplastic Agents
• BRCA1 Protein
• BRCA1 protein, human
• Guanine Nucleotide Exchange Factors
• HERC2 protein, human
• Ubiquitin-Protein Ligases

Topics

• Adult
• Aged
• Aged, 80 and over
• Antineoplastic Agents (therapeutic use)
• BRCA1 Protein (genetics)
• Carcinoma, Non-Small-Cell Lung (drug therapy, genetics)
• Disease Progression
• Female
• Gene Expression Regulation, Neoplastic
• Guanine Nucleotide Exchange Factors (genetics)
• Humans
• Lung Neoplasms (drug therapy, genetics)
• Male
• Middle Aged
• Prognosis
• Retrospective Studies
• Survival Analysis
• Treatment Outcome
• Ubiquitin-Protein Ligases