According to the results, we hypothesised that PTEN might have an important role as a downstream target of BRG1 in human CRC, because PTEN was a key tumour suppressor by suppressing the PI3K–Akt signalling pathway in a variety of human cancers (Li et al, 1997; Steck et al, 1997; Semba et al, 2009). This evidence concerns the gene PIK3CD and cancer.