Lentivirus-Mediated Knockdown of NOB1 Suppresses the Proliferation of Colon Cancer Cells

Abstract

NOB1 is important for ribosome biogenesis and protein degradation. Previous studies showed that it could regulate the growth and colony-formation ability of ovarian, breast and hepatocellular carcinoma cells. However, its function in colon cancer cells is largely unknown. In this study, we found that NOB1 could express in 6 different colon cancer cell lines. Lentivirus-mediated shRNA targeted NOB1 could suppress the endogenous gene expression. NOB1 depletion significantly inhibited cell proliferation and colony formation ability, as determined by MTT and colony formation assays. Flow cytometry analysis showed NOB1 silencing arrested cell cycle in G0 / G1 phase. Moreover, the percentage of cells at sub-G1 phase dramatically increased after NOB1 knockdown. These results indicate that NOB1 may play an important role in the growth and tumorigensis of colon cancer and knockdown of NOB1 may be a potential therapeutic method for colon cancer in the future.

Zusammenfassung

NOB1 spielt eine wichtige Rolle in der Ribosom-Biogenese und im Proteinabbau. Frühere Studien haben gezeigt, dass NOB1 Zellwachstum und die Fähigkeit Kolonien zu bilden in Ovarial-, Mamma- und hepatozellulärem Karzinom regulieren konnte. Die Funktion bei Kolonkarzinomzellen ist jedoch weitgehend unbekannt. In dieser Studie konnten wir zeigen, dass NOB1 in 6 verschiedenen Zelllinien des Kolonkarzinoms exprimiert werden konnte. Die endogene Genexpression konnte durch gezielte Deaktivierung von NOB1 durch lentivirus-vermittelte shRNA supprimiert werden. Durch die Depletion von NOB1 konnte die Zellproliferation und Koloniebildung signifikant unterdrückt werden, wie mittels MTT und Koloniebildungsassays gezeigt werden konnte. Die durchflusszytometrische Analyse ergab, dass die Abschaltung von NOB1 die Zellteilung in der G0-/G1-Phase zum Stillstand brachte. Zudem erhöhte sich nach Abschaltung von NOB1 der Prozentanteil jener Zellen in der sub-G1-Phase dramatisch. Diese Ergebnisse deuten darauf hin, dass NOB1 eine wichtige Rolle bei Wachstum und Tumorgenese des Kolonkarzinoms spielen könnte und dass die Abschaltung von NOB1 in Zukunft ein möglicher Therapieansatz bei Kolonkarzinom sein könnte.

Schlüsselwörter

gastrointestinale Blutung - gastrointestinaler Stromatumor (GIST) - gastro-entero-pankreatische Tumoren - NOB1 - Lentivirus - shRNA - Dickdarmkarzinom

Key words

gastrointestinal bleeding - gastrointestinal stroma tumor (GIST) - gastroenteropancreatic tumors - NOB1 - lentivirus - shRNA - colon cancer

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