We also analyzed the relationship between the mRNA levels of FGFR2, ERBB4, RET, FN1, MMP16, and SOX2 and tumor stages in breast cancer using GEPIA (Figure 3B) and found that the levels of FGFR2 were significantly upregulated in stage I and remained stable across stages II–X. The gene discussed is ERBB4; the disease is neoplasm.