Related Experiment Video
Updated: Jul 4, 2026

Describing a Transcription Factor Dependent Regulation of the MicroRNA Transcriptome
Published on: June 15, 2016
Role of STAT3 as a negative regulator in Mac2- binding protein expression
Yuk Pheel Park1, Jong-Tae Kim, Young Yang
1Stem cell Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea.
Background:
Mac-2 binding protein (Mac-2BP) is a secreted glycoprotein from the culture fluid of several human cancer cells, especially breast, lung, and gastric cells. Mac-2BP plays a role in immune response and cell adhesion activity in patients with various cancer and infectious diseases. In this study, we attempted to identify the regulators of Mac-2BP expression at the transcriptional level.
Methods:
To determine the effect of epidermal growth factor (EGF) to Mac-2BP expression in gastric cancers, we constructed the different lengths of Mac-2BP promoter plasmids and measured the promoter activity and Mac-2BP expression. In addition to investigating the role of signal transducer and activator of transcription3 (STAT3) or human telomerase reverse transcriptase (hTERT) as a regulator of Mac-2BP, we transfected the small interfering RNA (siRNA) specific for STAT3 or hTERT, and Mac-2BP level was observed by a quantitative ELISA.
Results:
EGF treatment could suppress the Mac-2BP transcription in HEK293 or gastric cancer cell lines (SNU-638 or AGS). In 5'-deleted promoter experiment, pGL3-Mac Pro-2377 transfected cells showed a decreased luciferase activity compared to pGL3-Mac Pro-2277. We also identified that (-2,366/-2,356) on Mac-2BP promoter is a putative STAT3 binding site and suppression of STAT3 with STAT3 specific siRNA increased the Mac-2BP level, suggesting the role of STAT3 as a negative regulator, in contrast to hTERT, which is known as a positive regulator.
Conclusions:
EGF signal is critical for the Mac-2BP expression, and more importantly, STAT3 could work as a negative regulator, while hTERT as a positive regulator in Mac-2BP transcription.
Related Concept Videos
The JAK-STAT Signaling Pathway
PI3K/mTOR/AKT Signaling Pathway
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Master Transcription Regulators
TGF - β Signaling Pathway
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
