Genetic Variants Associated With Cancer Therapy–Induced Cardiomyopathy
Authors: Garcia-Pavia Pablo , Kim Yuri , Restrepo-Cordoba Maria Alejandra , Lunde Ida G. , Wakimoto Hiroko , Smith Amanda M. , Toepfer Christopher N. , Getz Kelly , Gorham Joshua , Patel Parth , Ito Kaoru , Willcox Jonathan A. , Arany Zoltan , Li Jian , Owens Anjali T. , Govind Risha , Nuñez Beatriz , Mazaika Erica , Bayes-Genis Antoni , Walsh Roddy , Finkelman Brian , Lupon Josep , Whiffin Nicola , Serrano Isabel , Midwinter William , Wilk Alicja , Bardaji Alfredo , Ingold Nathan , Buchan Rachel , Tayal Upasana , Pascual-Figal Domingo A. , de Marvao Antonio , Ahmad Mian , Garcia-Pinilla Jose Manuel , Pantazis Antonis , Dominguez Fernando , John Baksi A. , O’Regan Declan P. , Rosen Stuart D. , Prasad Sanjay K. , Lara-Pezzi Enrique , Provencio Mariano , Lyon Alexander R. , Alonso-Pulpon Luis , Cook Stuart A. , DePalma Steven R. , Barton Paul J.R. , Aplenc Richard , Seidman Jonathan G. , Ky Bonnie , Ware James S. , Seidman Christine E. 
Published: April 2019

Background:
Cancer therapy–induced cardiomyopathy (CCM) is associated with cumulative drug exposures and preexisting cardiovascular disorders. These parameters incompletely account for substantial interindividual susceptibility to CCM. We hypothesized that rare variants in cardiomyopathy genes contribute to CCM.

Methods:
We studied 213 patients with CCM from 3 cohorts: retrospectively recruited adults with diverse cancers (n=99), prospectively phenotyped adults with breast cancer (n=73), and prospectively phenotyped children with acute myeloid leukemia (n=41). Cardiomyopathy genes, including 9 prespecified genes, were sequenced. The prevalence of rare variants was compared between CCM cohorts and The Cancer Genome Atlas participants (n=2053), healthy volunteers (n=445), and an ancestry-matched reference population. Clinical characteristics and outcomes were assessed and stratified by genotypes. A prevalent CCM genotype was modeled in anthracycline-treated mice.

Results:

CCM was diagnosed 0.4 to 9 years after chemotherapy; 90% of these patients received anthracyclines. Adult patients with CCM had cardiovascular risk factors similar to the US population. Among 9 prioritized genes, patients with CCM had more rare protein-altering variants than comparative cohorts (
P
≤1.98e–04). Titin-truncating variants (TTNtvs) predominated, occurring in 7.5% of patients with CCM versus 1.1% of The Cancer Genome Atlas participants (
P
=7.36e–08), 0.7% of healthy volunteers (
P
=3.42e–06), and 0.6% of the reference population (
P
=5.87e–14). Adult patients who had CCM with TTNtvs experienced more heart failure and atrial fibrillation (
P
=0.003) and impaired myocardial recovery (
P
=0.03) than those without. Consistent with human data, anthracycline-treated TTNtv mice and isolated TTNtv cardiomyocytes showed sustained contractile dysfunction unlike wild-type (
P
=0.0004 and
P
<0.002, respectively).

Conclusions:
Unrecognized rare variants in cardiomyopathy-associated genes, particularly TTNtvs, increased the risk for CCM in children and adults, and adverse cardiac events in adults. Genotype, along with cumulative chemotherapy dosage and traditional cardiovascular risk factors, improves the identification of patients who have cancer at highest risk for CCM.

Clinical Trial Registration:

URL:
https://www.clinicaltrials.gov
. Unique identifiers: NCT01173341; AAML1031; NCT01371981.