PKM1 Confers Metabolic Advantages and Promotes Cell-Autonomous Tumor Cell Growth

Publication date: 12 March 2018
Source:Cancer Cell, Volume 33, Issue 3
Author(s): Mami Morita, Taku Sato, Miyuki Nomura, Yoshimi Sakamoto, Yui Inoue, Ryota Tanaka, Shigemi Ito, Koreyuki Kurosawa, Kazunori Yamaguchi, Yuki Sugiura, Hiroshi Takizaki, Yoji Yamashita, Ryuichi Katakura, Ikuro Sato, Masaaki Kawai, Yoshinori Okada, Hitomi Watanabe, Gen Kondoh, Shoko Matsumoto, Ayako Kishimoto, Miki Obata, Masaki Matsumoto, Tatsuro Fukuhara, Hozumi Motohashi, Makoto Suematsu, Masaaki Komatsu, Keiichi I. Nakayama, Toshio Watanabe, Tomoyoshi Soga, Hiroshi Shima, Makoto Maemondo, Nobuhiro Tanuma
Expression of PKM2, which diverts glucose-derived carbon from catabolic to biosynthetic pathways, is a hallmark of cancer. However, PKM2 function in tumorigenesis remains controversial. Here, we show that, when expressed rather than PKM2, the PKM isoform PKM1 exhibits a tumor-promoting function in KRAS^G12D-induced or carcinogen-initiated mouse models or in some human cancers. Analysis of Pkm mutant mouse lines expressing specific PKM isoforms established that PKM1 boosts tumor growth cell intrinsically. PKM1 activated glucose catabolism and stimulated autophagy/mitophagy, favoring malignancy. Importantly, we observed that pulmonary neuroendocrine tumors (NETs), including small-cell lung cancer (SCLC), express PKM1, and that PKM1 expression is required for SCLC cell proliferation. Our findings provide a rationale for targeting PKM1 therapeutically in certain cancer subtypes, including pulmonary NETs.

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Teaser

The relative importance of PKM isoforms in tumor growth has been controversial. Morita et al. show that PKM1 promotes the growth of multiple tumor models using mouse lines expressing PKM1 or PKM2 from the endogenous Pkm locus. PKM1 is expressed in human SCLC, and it is important for SCLC cell proliferation.


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