Matrix metalloproteinase 2 secretion in WEHI 164 fibrosarcoma cells is nitric oxide-related and modified by morphine.

Matrix metalloproteinases (MMP) are ubiquitous enzymes involved in extracellular matrix remodeling, and as a consequence in a number of physiological and pathological states, including development, wound healing and cancer. A crucial feature of cancer progression and metastasis is the disruption of extracellular matrix, and spreading of proliferating cancer cells. Modulation of MMP is a main target of cancer research. Using the mouse fibrosarcoma cell line WEHI 164, producing high amounts of MMP-2, we investigated whether we could modulate its production. We report that MMP-2 is under the control of nitric oxide (NO)/nitric oxide synthase (NOS) system. In addition, we show that NOS activity is controlled by opioids in a non-opioid receptor-related manner. Finally, we provide evidence that morphine, when administrated at low, non-toxic concentrations (<10(-9) M) attenuates MMP-2 activity. We conclude that, as morphine is able to decrease metalloproteinase activity via the NO/NOS system, it may have a place in the treatment of several sarcomas including fibrosarcoma.