STAT-3, ELK-1, and c- Jun contributes IL-6 mediated ADAMTS-8 upregulation in colorectal cancer

Area of Science:

• Molecular Biology
• Cancer Research
• Biochemistry

Background:

• ADAMTSs (A Disintegrin and Metalloproteinase with Thrombospondin Motifs) are crucial extracellular matrix modulators implicated in tumorigenesis.
• ADAMTS-8, an anti-angiogenic member, is frequently dysregulated in various cancers, with its tumor suppressor role established in colorectal cancer.
• The transcriptional regulation of ADAMTS-8, despite its critical role in tumor progression, remains largely uninvestigated.

Purpose of the Study:

• To elucidate the transcriptional regulatory mechanisms governing ADAMTS-8 expression.
• To investigate the impact of inflammatory signaling, specifically Interleukin-6 (IL-6), on ADAMTS-8 gene regulation.

Main Methods:

• Cloning of the human ADAMTS-8 promoter into a reporter vector for transient transfection assays in SW480 cells.
• Assessment of IL-6's effect on ADAMTS-8 promoter activity, mRNA, and protein levels using reporter assays, QRT-PCR, and Western blot.
• Evaluation of transcription factor binding to the ADAMTS-8 promoter via Chromatin Immunoprecipitation quantitative PCR (ChIP qPCR) and Electrophoretic Mobility Shift Assay (EMSA).

Main Results:

• The ADAMTS-8 promoter contains multiple transcription factor binding sites responsive to inflammatory pathways.
• IL-6 stimulation significantly enhanced ADAMTS-8 promoter activity, mRNA, and protein expression.
• IL-6-induced ADAMTS-8 expression is mediated by p38/MAPK, NF-κB, PI3K, and SAPK/JNK signaling pathways, with STATs, Elk-1, and c-Jun identified as functional binding factors.

Conclusions:

• Inflammation acts as a potent positive regulator of the ADAMTS-8 gene.
• Understanding these regulatory mechanisms provides insights into cancer progression and potential therapeutic targets.