Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23

ePoster Display

1662P - Comprehensive analysis of the metabolic enzymes in patients with small cell lung cancer using a large-scale targeted proteomics assay


16 Sep 2021


ePoster Display


Gouji Toyokawa


Annals of Oncology (2021) 32 (suppl_5): S1164-S1174. 10.1016/annonc/annonc680


G. Toyokawa1, M. Kodama2, N. Haratake3, Y. Yamada4, H. Kittaka5, T. Takenaka3, K. Tanaka6, M. Shimokawa7, K. Yamazaki1, S. Takeo1, I. Okamoto6, Y. Oda4, K.I. Nakayama2

Author affiliations

  • 1 Department Of Thoracic Surgery, Clinical Research Institute, National Hospital Organization, Kyushu Medical Center, 810-8563 - Fukuoka/JP
  • 2 Department Of Molecular And Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 812-8582 - Fukuoka/JP
  • 3 Department Of Surgery And Science, Graduate School of Medical Sciences, Kyushu University, 812-8582 - Fukuoka/JP
  • 4 Department Of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, 812-8582 - Fukuoka/JP
  • 5 Department Of Clinical Research, Kyushu Pro Search LLP, 819-0388 - Fukuoka/JP
  • 6 Research Institute For Diseases Of The Chest, Graduate School of Medical Sciences, Kyushu University, 812-8582 - Fukuoka/JP
  • 7 Department Of Biostatistics, Yamaguchi University Graduate School of Medicine, 755-8505 - Yamaguchi/JP

Abstract 1662P


Small cell lung cancer (SCLC) is a devastating subtype of lung cancer, and its biological, clinical and genetic characteristics differ from those associated with non-small cell lung cancer. Despite the comprehensive genetic analysis of SCLC, promising therapeutic targets have yet to be identified. However, there is growing evidence to support that the cellular metabolic system contributes decisively to malignancy in SCLC.


We applied in vitro proteome-assisted multiple reaction monitoring for protein absolute quantification (iMPAQT), which can allow absolute quantification of 342 metabolic enzymes. Frozen samples obtained from 36 patients with surgically resected SCLC (n = 12), adenocarcinoma (ADC; n = 12) and squamous cell carcinoma (SCC; n = 12) were analyzed by iMPAQT. An enrichment analysis was used to identify metabolic pathways specifically varying in SCLC. One-way ANOVA was used to compare the enzyme expression levels among the three groups. P-value of <0.05 were considered to indicate statistical significance.


The iMPAQT analysis revealed a definitive difference in the absolute amount of the metabolic enzymes between SCLC, ADC and SCC. The purine metabolic pathway was the most upregulated pathway among the metabolic pathways that specifically vary in SCLC (P = 1.1 x 10-10). Among enzymes associated with purine metabolism, only hypoxanthine guanine phosphoribosyltransferase 1 (HPRT1), a key enzyme for the salvage pathway of purine metabolism, was significantly overexpressed in SCLC in comparison to ADC and SCC (P = 2.0 x 10-6). The higher expression of HPRT1 was significantly associated with a larger tumor size (P = 2.0 x 10-3) and poorer overall survival in patients with SCLC (P = 7.9 x 10-3).


The current study showed that purine metabolic enzymes, especially HPRT1, were significantly upregulated in SCLC in comparison to ADC and SCC. Furthermore, the absolute amount of HPRT1 was larger in SCLC patients with larger tumors and a poor prognosis. These results suggest that HPRT1 may be associated with the tumorigenesis of SCLC and contribute to the acquisition of malignant traits, which should be clarified by the further experimental analyses at the molecular level.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.


Takeda Science Foundation; Clinical Research Promotion Foundation.


All authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings
  • Necessary cookies enable core functionality. The website cannot function properly without these cookies, and you can only disable them by changing your browser preferences.