A novel screen using the Reck tumor suppressor gene promoter detects both conventional and metastasis-suppressing anticancer drugs

Abstract

AbstrAct:The membrane-anchored matrix metalloproteinase-regulator RECK is often downregulated in various types of cancers; the levels of residual RECK in resected tumors often correlate with better prognosis. Forced expression of RECK in cancer cells suppresses tumor angiogenesis, invasion, and metastasis in xenograft models. RECK is therefore a promising marker for benignancy and a potential effector in cancer therapy. We established a cell line containing two transgene systems: (1) the secreted alkaline phosphatase (SEAP) gene fused to Reck promoter and (2) the HRAS 12V oncogene driven by the Tet-off promoter system. This cell line exhibits transformed phenotype in regular medium and flat morphology with increased SEAP activity in the presence of doxycycline, allowing the assessment of RECK-inducing activity of chemicals in the contexts of both transformed and untransformed cells. Our pilot experiments with 880 known bioactive compounds detected 34 compounds that activate RECK promoter; among these, 10 were authentic anticancer drugs. Four selected compounds up-regulated endogenous RECK protein in several human cancer cell lines. The top-ranking compound, disulfiram, strongly suppressed spontaneous lung-metastasis of human fibrosarcoma cells in nude mice. Our data demonstrate the value of this screen in discovering effective cancer therapeutics.

Concise Review: Bullseye: Targeting Cancer Stem Cells to Improve the Treatment of Gliomas by Repurposing Disulfiram

“…In a small number of cell‐based models they were also able to show that DSF suppressed the growth of cells that had metastasized to the lymph nodes and lungs . Consistent with this study, DSF was identified in a large screen for antimetastatic agents using a model of fibrosarcoma . Given that 90% of all cancer deaths are due to metastases it is encouraging that DSF could provide some benefit in cancers that have spread.…”

Lessons from tumor reversion for cancer treatment

“…This group developed an original screening method based on the activation of the Reck-promoter fused to the secreted alkaline phosphatase gene [57]. Interestingly, disulfiram, a drug used to cure chronic alcoholism, appeared to be the most potent inducer of RECK, suppressing lung metastasis in a fibrosarcoma mouse model [57]. Interestingly, disulfiram, a drug used to cure chronic alcoholism, appeared to be the most potent inducer of RECK, suppressing lung metastasis in a fibrosarcoma mouse model [57].…”

Pattern of RECK CpG methylation as a potential marker for predicting breast cancer prognosis and drug-sensitivity

“…Next, we treated four cell lines that exhibit different RECK methylation patterns [T-47D (RPM+RIM+), MCF7 (RPM-RIM+), BT549 and SKBR3 (RPM-RIM-)] with a RECK-activating anticancer drug, methotrexate (MTX) [35]. T-47D (RPM+) showed lowest sensitivity to this drug (Figure 5C; red line).…”

“…A recent study indicate that progesterone inhibits estrogen-induced growth of ER+ breast tumors and that copy number loss of the PR gene is not rare among ER+ breast cancers [37]. The use of DNMT inhibitors in conjunctions with other therapeutic agents, such as anti-estrogens, Cdk inhibitors [38], HDAC inhibitors, or other RECK -activating agents [35], may have potential value in treating such tumors.…”