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Updated: Feb 4, 2026
Invasive Behavior of Human Breast Cancer Cells in Embryonic Zebrafish
Published on: April 25, 2017
Leptin stimulates IGF-1 transcription by activating AP-1 in human breast cancer cells
Dong Yeong Min1, Euitaek Jung1, Juhwan Kim1
1Department of Biological Sciences, Sanghuh College of Lifesciences, Koknkuk University, Seoul 05029, China.
Abstract:
Leptin, an adipokine regulating energy metabolism, appears to be associated with breast cancer progression. Insulin-like growth factor-1 (IGF-1) mediates the pathogenesis of breast cancer. The regulation of IGF-1 expression by leptin in breast cancer cells is unclear. Here, we found that leptin upregulates IGF-1 expression at the transcriptional level in breast cancer cells. Activating protein-1 (AP-1)-binding element within the proximal region of IGF-1 was necessary for leptin-induced IGF-1 promoter activation. Forced expression of AP-1 components, c-FOS or c-JUN, enhanced leptin-induced IGF-1 expression, while knockdown of c-FOS or c-JUN abrogated leptin responsiveness. All three MAPKs (ERK1/2, JNK1/2, and p38 MAPK) mediated leptin-induced IGF-1 expression. These results suggest that leptin contributes to breast cancer progression through the transcriptional upregulation of leptin via the MAPK pathway. [BMB Reports 2019; 52(6): 385-390].
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