According to Cheng Chuanle et al., the expression of RGS4 was higher in normal lung tissues than in non-small cell lung cancer specimens, and correlation analysis showed that the expression level of RGS4 was negatively correlated with lymph node metastasis and TNM stage, leading to RGS4 being considered a novel tumour suppressor. This evidence concerns the gene RGS4 and neoplasm.