A novel small-molecule inhibitor suppresses colon cancer metastasis through inhibition of metastasis-associated in colon cancer-1 transcription

SummaryWe previously reported that the metastasis-associated in colon cancer-1 (MACC-D1) is overexpressed in colon cancer. However, so far, only a few effective MACC-1 inhibitors have been identified. To discover novel transcriptional inhibitors of MACC-1, we performed a luciferase reporter-based high-throughput screening (HTS). This strategy discovered rottlerin as an inhibitor of MACC-1 transcription was able to reduce cell motility in colon cancer in time- and dose-dependent manners. Wound healing assay indicated that 48-h treatment with 2.5  μM rottlerin impairs wound closure compared to the controls. Electrophoretic mobility shift assays showed that rottlerin inhibits the binding of the transcriptional activators Sp1 and c-Jun with human MACC-1 promoter. A combination of Western blot assays and expression analyses by qRT-PCR ruled o ut that rottlerin may act indirectly through inhibition of c-Jun or Sp1 expression to decrease MACC-1 expression in human colon cancer cell lines SW620. Rather, these results support that rottlerin restricts the binding of MACC-1 promoter directly by c-Jun and Sp1 in colon cancer cells. Thus, as a s mall-molecule inhibitor of MACC-1, rottlerin may benefit colon cancer patients by suppressing MACC-1-dependent tumor growth and metastasis.
Source: Investigational New Drugs - Category: Drugs & Pharmacology Source Type: research