[HTML][HTML] 67-kDa laminin receptor increases cGMP to induce cancer-selective apoptosis

M Kumazoe, K Sugihara, S Tsukamoto… - The Journal of …, 2013 - Am Soc Clin Investig
M Kumazoe, K Sugihara, S Tsukamoto, Y Huang, Y Tsurudome, T Suzuki, Y Suemasu…
The Journal of clinical investigation, 2013Am Soc Clin Investig
The 67-kDa laminin receptor (67LR) is a laminin-binding protein overexpressed in various
types of cancer, including bile duct carcinoma, colorectal carcinoma, cervical cancer, and
breast carcinoma. 67LR plays a vital role in growth and metastasis of tumor cells and
resistance to chemotherapy. Here, we show that 67LR functions as a cancer-specific death
receptor. In this cell death receptor pathway, cGMP initiated cancer-specific cell death by
activating the PKCδ/acid sphingomyelinase (PKCδ/ASM) pathway. Furthermore …
The 67-kDa laminin receptor (67LR) is a laminin-binding protein overexpressed in various types of cancer, including bile duct carcinoma, colorectal carcinoma, cervical cancer, and breast carcinoma. 67LR plays a vital role in growth and metastasis of tumor cells and resistance to chemotherapy. Here, we show that 67LR functions as a cancer-specific death receptor. In this cell death receptor pathway, cGMP initiated cancer-specific cell death by activating the PKCδ/acid sphingomyelinase (PKCδ/ASM) pathway. Furthermore, upregulation of cGMP was a rate-determining process of 67LR-dependent cell death induced by the green tea polyphenol (–)-epigallocatechin-3-O-gallate (EGCG), a natural ligand of 67LR. We found that phosphodiesterase 5 (PDE5), a negative regulator of cGMP, was abnormally expressed in multiple cancers and attenuated 67LR-mediated cell death. Vardenafil, a PDE5 inhibitor that is used to treat erectile dysfunction, significantly potentiated the EGCG-activated 67LR-dependent apoptosis without affecting normal cells and prolonged the survival time in a mouse xenograft model. These results suggest that PDE5 inhibitors could be used to elevate cGMP levels to induce 67LR-mediated, cancer-specific cell death.
The Journal of Clinical Investigation