High correlation between CA12 and ESR1 expression is reproducible in the TCGA Firehose Legacy dataset comprising 960 breast tumor transcriptomes (Pearson correlation coefficient of 0.80, Figure S3A) and in the 1904 breast cancer samples from the METABRIC dataset (Pearson correlation coefficient of 0.79, Figure S3B). The gene discussed is ESR1; the disease is breast cancer.