Biomaterial Database

Extracellular PKCδ signals to epidermal growth factor receptor for tumor proliferation in liver cancer cells. 2022

Kohji Yamada, and Ryusuke Kizawa, and Ayano Yoshida, and Rei Koizumi, and Saya Motohashi, and Yuya Shimoyama, and Yoshito Hannya, and Saishu Yoshida, and Tsunekazu Oikawa, and Masayuki Shimoda, and Kiyotsugu Yoshida

Department of Biochemistry, The Jikei University School of Medicine, Tokyo, Japan.

Protein kinase C delta (PKCδ) is a multifunctional PKC family member and has been implicated in many types of cancers, including liver cancer. Recently, we have reported that PKCδ is secreted from liver cancer cells, and involved in cell proliferation and tumor growth. However, it remains unclear whether the extracellular PKCδ directly regulates cell surface growth factor receptors. Here, we identify epidermal growth factor receptor (EGFR) as a novel interacting protein of the cell surface PKCδ in liver cancer cells. Imaging studies showed that secreted PKCδ interacted with EGFR-expressing cells in both autocrine and paracrine manners. Biochemical analysis revealed that PKCδ bound to the extracellular domain of EGFR. We further found that a part of the amino acid sequence on the C-terminal region of PKCδ was similar to the putative EGFR binding site of EGF. In this regard, the point mutant of PKCδ in the binding site lacked the ability to bind to the extracellular domain of EGFR. Upon an extracellular PKCδ-EGFR association, ERK1/2 activation, downstream of EGFR signaling, was apparently induced in liver cancer cells. This study indicates that extracellular PKCδ behaves as a growth factor and provides a molecular basis for extracellular PKCδ-targeting therapy for liver cancer.

UI	MeSH Term	Description	Entries
D008113	Liver Neoplasms	Tumors or cancer of the LIVER.	Cancer of Liver,Hepatic Cancer,Liver Cancer,Cancer of the Liver,Cancer, Hepatocellular,Hepatic Neoplasms,Hepatocellular Cancer,Neoplasms, Hepatic,Neoplasms, Liver,Cancer, Hepatic,Cancer, Liver,Cancers, Hepatic,Cancers, Hepatocellular,Cancers, Liver,Hepatic Cancers,Hepatic Neoplasm,Hepatocellular Cancers,Liver Cancers,Liver Neoplasm,Neoplasm, Hepatic,Neoplasm, Liver
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D004815	Epidermal Growth Factor	A 6-kDa polypeptide growth factor initially discovered in mouse submaxillary glands. Human epidermal growth factor was originally isolated from urine based on its ability to inhibit gastric secretion and called urogastrone. Epidermal growth factor exerts a wide variety of biological effects including the promotion of proliferation and differentiation of mesenchymal and EPITHELIAL CELLS. It is synthesized as a transmembrane protein which can be cleaved to release a soluble active form.	EGF,Epidermal Growth Factor-Urogastrone,Urogastrone,Human Urinary Gastric Inhibitor,beta-Urogastrone,Growth Factor, Epidermal,Growth Factor-Urogastrone, Epidermal,beta Urogastrone
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D049109	Cell Proliferation	All of the processes involved in increasing CELL NUMBER including CELL DIVISION.	Cell Growth in Number,Cellular Proliferation,Cell Multiplication,Cell Number Growth,Growth, Cell Number,Multiplication, Cell,Number Growth, Cell,Proliferation, Cell,Proliferation, Cellular
D051745	Protein Kinase C-delta	A ubiquitously expressed protein kinase that is involved in a variety of cellular SIGNAL PATHWAYS. Its activity is regulated by a variety of signaling protein tyrosine kinase.	PKC-delta Serine-Threonine Kinase,Kinase C-delta, Protein,PKC delta Serine Threonine Kinase,Protein Kinase C delta,Serine-Threonine Kinase, PKC-delta
D066246	ErbB Receptors	A family of structurally related cell-surface receptors that signal through an intrinsic PROTEIN-TYROSINE KINASE. The receptors are activated upon binding of specific ligands which include EPIDERMAL GROWTH FACTORS, and NEUREGULINS.	EGF Receptor,Epidermal Growth Factor Receptor,Epidermal Growth Factor Receptor Family Protein,Epidermal Growth Factor Receptor Protein-Tyrosine Kinase,ErbB Receptor,HER Family Receptor,Receptor, EGF,Receptor, Epidermal Growth Factor,Receptor, TGF-alpha,Receptor, Transforming-Growth Factor alpha,Receptor, Urogastrone,Receptors, Epidermal Growth Factor-Urogastrone,TGF-alpha Receptor,Transforming Growth Factor alpha Receptor,Urogastrone Receptor,c-erbB-1 Protein,erbB-1 Proto-Oncogene Protein,EGF Receptors,Epidermal Growth Factor Receptor Family Proteins,Epidermal Growth Factor Receptor Kinase,HER Family Receptors,Proto-oncogene c-ErbB-1 Protein,Receptor Tyrosine-protein Kinase erbB-1,Receptor, ErbB-1,Receptors, Epidermal Growth Factor,Epidermal Growth Factor Receptor Protein Tyrosine Kinase,ErbB-1 Receptor,Family Receptor, HER,Family Receptors, HER,Proto oncogene c ErbB 1 Protein,Proto-Oncogene Protein, erbB-1,Receptor Tyrosine protein Kinase erbB 1,Receptor, ErbB,Receptor, ErbB 1,Receptor, HER Family,Receptor, TGF alpha,Receptor, Transforming Growth Factor alpha,Receptors, EGF,Receptors, Epidermal Growth Factor Urogastrone,Receptors, ErbB,Receptors, HER Family,c erbB 1 Protein,c-ErbB-1 Protein, Proto-oncogene,erbB 1 Proto Oncogene Protein