Fig. 1.

Identifying the tumor-protective growth differentiation factor (GDF) genes. (A) The gene expression of 10 GDFs between hepatocellular carcinoma (HCC) and tumor-adjacent tissues in The Cancer Genome Atlas (TCGA) data and (B) comparison of differential expression of every GDF gene in HCC and tumor-adjacent tissues using TCGA data. The red block indicates increased expression in tumor, whereas the blue block indicates decreased expression in tumor. T, tumor; N, nontumor. (C) The mRNA expression levels of GDF2, GDF6, and GDF7 in the paired HCC and tumor-adjacent tissues (n = 30). Compared by paired Student’s t-test. ^∗∗P < 0.01, ^∗∗∗P < 0.001. Kaplan–Meier analysis of the overall survival and recurrence-free survival in terms of differential expression groups based on (D) GDF2, (E) GDF6, and (F) GDF7. Analyzed by GEPIA (http://gepia.cancer-pku.cn/).