title: Malignant progressive tumor cell clone exhibits significant up-regulation of cofilin-2 and 27-kDa modified form of cofilin-1 compared to regressive clone.
abstract: QR-32 is a regressive murine fibrosarcoma cell clone which cannot grow when they are transplanted in mice; QRsP-11 is a progressive malignant tumor cell clone derived from QR-32 which shows strong tumorigenicity. A recent study showed there to be differentially expressed up-regulated and down-regulated proteins in these cells, which were identified by proteomic differential display analyses by using two-dimensional gel electrophoresis and mass spectrometry. Cofilins are small proteins of less than 20 kDa. Their function is the regulation of actin assembly. Cofilin-1 is a small ubiquitous protein, and regulates actin dynamics by means of binding to actin filaments. Cofilin-1 plays roles in cell migration, proliferation and phagocytosis. Cofilin-2 is also a small protein, but it is mainly expressed in skeletal and cardiac muscles. There are many reports showing the positive correlation between the level of cofilin-1 and cancer progression. We have also reported an increased expression of cofilin-1 in pancreatic cancer tissues compared to adjacent paired normal tissues. On the other hand, cofilin-2 was significantly less expressed in pancreatic cancer tissues. Therefore, the present study investigated the comparison of the levels of cofilin-1 and cofilin-2 in regressive QR-32 and progressive QRsP-11cells by western blotting. Cofilin-2 was significantly up-regulated in QRsP-11 compared to QR-32 cells (p<0.001). On the other hand, the difference of the intensities of the bands of cofilin-1 (18 kDa) in QR-32 and QRsP-11 was not significant. However, bands of 27 kDa showed a quite different intensity between QR-32 and QRsP-11, with much higher intensities in QRsP-11 compared to QR-32 (p<0.001). These results suggested that the 27-kDa protein recognized by the antibody against cofilin-1 is a possible biomarker for progressive tumor cells.
authors.affiliation: Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan. climates@yamaguchi-u.ac.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kuramitsu
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Futoshi
authors.initials: F
authors.lastname: Okada
authors.forename: Byron
authors.initials: B
authors.lastname: Baron
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tokuda
authors.forename: Takao
authors.initials: T
authors.lastname: Kitagawa
authors.forename: Junko
authors.initials: J
authors.lastname: Akada
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002999:Clone Cells; D051338:Cofilin 1 / Q000378:metabolism*; D051340:Cofilin 2 / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005354:Fibrosarcoma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D013058:Mass Spectrometry; D051379:Mice; D015854:Up-Regulation
chemical_list: D051338:Cofilin 1; D051340:Cofilin 2
keywords: Cofilin-1; cofilin-2; fibrosarcoma; progression; regression