Interestingly, application of β-carotene supplements contributed to a significant reduction in the occurrence of metastasis and tumour volume, with a concordant decrease in transcription of MMP-2 and increased activity of TIMPs (TIMP-1 and -2) in immunodeficient nude mice treated with SK-N-BE(2)C tumour cells, suggesting their independent association with MMPs. The gene discussed is TIMP1; the disease is neoplasm.