Novel metastasis-related gene CIM functions in the regulation of multiple cellular stress-response pathways.
Various stresses of the tumor microenvironment produced by insufficient nutrients, pH, and oxygen can contribute to the generation of altered metabolic and proliferative states that promote the survival of metastatic cells. Among many cellular stress-response pathways activated under such conditions are the hypoxia-inducible factor (HIF) pathway and the unfolded protein response (UPR), which is elicited as a response to endoplasmic reticulum (ER) stress. In this study, we report the identification of a novel cancer invasion and metastasis-related gene (hereafter referred to as CIM, also called ERLEC1), which influences both of these stress-response pathways to promote metastasis. CIM was identified by comparing the gene expression profile of a highly metastatic human lung cancer cell line with its weakly metastatic parental clone. We showed that CIM is critical for metastatic properties in this system. Proteomic approaches combined with bioinformatic analyses revealed that CIM has multifaceted roles in controlling the response to hypoxia and ER stress. Specifically, CIM sequestered OS-9 from the HIF-1α complex and PHD2, permitting HIF-1α accumulation by preventing its degradation. Ectopic expression of CIM in lung cancer cells increased their tolerance to hypoxia. CIM also modulated UPR through interaction with the key ER stress protein BiP, influencing cell proliferation under ER stress conditions. Our findings shed light on how tolerance to multiple cellular stresses at a metastatic site can be evoked by an integrated mechanism involving CIM, which can function to coordinate those responses in a manner that promotes metastatic cell survival.
Division of Molecular Carcinogenesis, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Kiyoshi
K
Yanagisawa
Hiroyuki
H
Konishi
Chinatsu
C
Arima
Shuta
S
Tomida
Toshiyuki
T
Takeuchi
Yukako
Y
Shimada
Yasushi
Y
Yatabe
Tetsuya
T
Mitsudomi
Hirotaka
H
Osada
Takashi
T
Takahashi
D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D015687:Cell Hypoxia; D045744:Cell Line, Tumor; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D057809:HEK293 Cells; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism; D037102:Lectins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D016513:Mice, SCID; D009362:Neoplasm Metastasis / Q000235:genetics; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D009374:Neoplasms, Experimental / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D040901:Proteomics; D034622:RNA Interference; D015398:Signal Transduction / Q000235:genetics* / Q000502:physiology; D013312:Stress, Physiological / Q000235:genetics* / Q000502:physiology; D014183:Transplantation, Heterologous; D056811:Unfolded Protein Response
C531192:ERLEC1 protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D037102:Lectins; D009363:Neoplasm Proteins; C098898:OS9 protein, human