Furthermore, we tested the expression of FZD2, SFRP2, STK31, and LALBA proteins in canine mammary (CF41 and P114) and human breast cancer cells lines (HCC1500, T47D, DCIS.com, MDA231, and MCF7) (Figure 3A and Figure S1A–E). Here, FZD2 is linked to breast carcinoma.