Wnt/β-catenin is a key signaling pathway in cancer cell proliferation. Wnt signaling was highly activated in MDA-MB-231 and T47D cells when CCT-3 was upregulated. In contrast, knocking down of CCT-3 knocked down the Wnt signaling significantly. The protein level of p-GSK- 3β and β-catenin nuclear accumulation increased in CCT3-overexpressed MDA-MB-231 and T47D cells. CCT-3 also affected the expression levels of β-catenin downstream effectors such as cyclin D1 and c-myc. This evidence concerns the gene CCT3 and cancer.