title: Fascin phosphorylation sites combine to regulate esophageal squamous cancer cell behavior.
abstract: Filopodia are dynamic membrane extensions generated by F-actin bundling and are involved in cancer cell migration, invasion and metastasis. Fascin is the crucial actin-bundling protein in filopodia, with phosphorylation at fascin serine 39 being well characterized to regulate fascin-mediated actin bundling in filopodia. However, increasing evidence indicates that fascin is phosphorylated at a number of sites. Whether phosphorylation at other sites also regulates fascin function is unknown. In this study, we show that four potential phosphorylation sites in fascin, specifically tyrosine 23, serine 38, serine 39 and serine 274, regulate cell behavior and filopodia formation in esophageal squamous cancer cells. Expression of non-phosphorylatable mutations at each of the four sites promoted anchorage-independent growth, cell motility and filopodia formation, whereas phosphomimetic mutations at each of these sites inhibited these cell behaviors, implying that fascin function in esophageal squamous cancer is regulated by fascin phosphorylation at multiple sites. Furthermore, phosphorylation at S38 and S39 cooperatively regulated cell behavior and filopodia formation, with dual dephosphorylation at both S38 and S39 residues maximally enhancing cell proliferation, migration and filopodia formation, and phosphorylation at any of the two phosphorylatable sites resulting in reduced enhancement. Taken together, our results reveal that phosphorylation at fascin amino acids Y23, S38, S39 and S274, in combination, downregulates the extent of anchorage-independent growth, cell migration and filopodia formation in esophageal squamous cancer cells.
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China.|Department of Biochemistry and Molecular Biology, Shantou University Medical College, 22 Xinling Road, Shantou, 515041, People's Republic of China.
authors.forename: Fa-Min
authors.initials: FM
authors.lastname: Zeng
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China.|Department of Biochemistry and Molecular Biology, Shantou University Medical College, 22 Xinling Road, Shantou, 515041, People's Republic of China.
authors.forename: Xiao-Ning
authors.initials: XN
authors.lastname: Wang
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China.|Department of Biochemistry and Molecular Biology, Shantou University Medical College, 22 Xinling Road, Shantou, 515041, People's Republic of China.
authors.forename: Hong-Shun
authors.initials: HS
authors.lastname: Shi
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China.|Department of Biochemistry and Molecular Biology, Shantou University Medical College, 22 Xinling Road, Shantou, 515041, People's Republic of China.
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Xie
authors.affiliation: Institute of Oncologic Pathology, Shantou University Medical College, No. 22, Xinling Road, Shantou, 515041, Guangdong, People's Republic of China.|Department of Pathology, Shantou Central Hospital, Shantou, 515041, Guangdong, People's Republic of China.
authors.forename: Ze-Peng
authors.initials: ZP
authors.lastname: Du
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China.|Institute of Oncologic Pathology, Shantou University Medical College, No. 22, Xinling Road, Shantou, 515041, Guangdong, People's Republic of China.
authors.forename: Lian-Di
authors.initials: LD
authors.lastname: Liao
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China.|Department of Biochemistry and Molecular Biology, Shantou University Medical College, 22 Xinling Road, Shantou, 515041, People's Republic of China.
authors.forename: Ping-Juan
authors.initials: PJ
authors.lastname: Nie
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China. lyxu@stu.edu.cn.|Institute of Oncologic Pathology, Shantou University Medical College, No. 22, Xinling Road, Shantou, 515041, Guangdong, People's Republic of China. lyxu@stu.edu.cn.
authors.forename: Li-Yan
authors.initials: LY
authors.lastname: Xu
authors.affiliation: The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou, 515041, Guangdong, People's Republic of China. nmli@stu.edu.cn.|Department of Biochemistry and Molecular Biology, Shantou University Medical College, 22 Xinling Road, Shantou, 515041, People's Republic of China. nmli@stu.edu.cn.
authors.forename: En-Min
authors.initials: EM
authors.lastname: Li
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002465:Cell Movement; D004847:Epithelial Cells / Q000378:metabolism* / Q000473:pathology; D004947:Esophagus / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D011554:Pseudopodia / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D012694:Serine / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D000199:Actins; D002352:Carrier Proteins; C502658:FSCN1 protein, human; D008840:Microfilament Proteins; D014443:Tyrosine; D012694:Serine
keywords: Fascin; Filopodia; Migration; Proliferation