Fig. 1
Downregulation of RCAN1.4 and its clinical relevance in breast cancer. a The heatmap of 10 downregulated genes located on HSA21 in breast cancer. The FPKM values of 112 pairs of breast cancer invasive samples and adjacent normal samples were retrieved from TCGA database. b TCGA analysis showed the expression levels of RCAN1 transcript isoforms in breast cancer tissues and normal tissues using the ISOexpresso website (http://wiki.tgilab.org/ISOexpresso/). c Immunoblot results of RCAN1.4 and RCAN1.1 protein expression in 15 pairs of matched breast tissue. Blue star, RCAN1.1; Red closed circle, RCAN1.4. d-e Kaplan-Meier analyses of RFS based on RCAN1(215253_at) mRNA levels in all breast cancer patients (d) and Kaplan-Meier analyses of OS based on RCAN1(208370_at) mRNA levels in the breast cancer patients with lymph node positive subgroup (e) were performed by using the KM-plotter breast cancer database (http://kmplot.com/analysis). Auto select best cutoff was chosen to split RCAN1-high and low groups in the analysis. Univariate Cox proportional hazards regression was carried out to identify HR and 95% CI. f The representative images of strong RCAN1.4 staining in the matched adjacent normal cells (N) and weak staining in tumor cells (T) (Left). Quantitative IHC analysis of RCAN1.4 staining of primary breast tumours and adjacent normal breast tissues was shown (n = 99, right). The P value was determined by Wilcoxon matched-pairs signed rank test (two-sided). g The representative images for low and high expression of RCAN1.4 staining in 258 primary breast cancer tissues were shown (left). Kaplan-Meier plots of the overall survival of patients, stratified by protein expression of RCAN1.4 (right). h The expression of RCAN1.4 in breast cancer tissue without or with distant metastasis. The P value was determined by an unpaired non-parametric Mann-Whitney test (two-sided). Error bars in f, h represented lower hinge - 1.5 * IQR to upper hinge + 1.5 * IQR (where IQR is the inter-quartile range, or distance between the first and third quartiles)