Herein, we developed a 99mTc labeled membrane type I matrix metalloproteinase (MT1-MMP) specific binding peptide, [99mTc]-(HYNIC-AF7p)(tricine)(TPPTS), for in vivo detection of MDA-MB-231 breast tumor by single photon emission computed tomography (SPECT). This evidence concerns the gene MMP14 and breast neoplasm.