Page 41 - SDIR5 Abstract book 21 12 2021.

POSTER PRESENTATIONS

POSTER SESSION

P1

Pan-cancer analysis of the role of flap endonuclease 1 (FEN1) in human various tumors

1,2
2
Hongling Yuan , Zekiye Altun
1 İzmir International BioMedicine and Genome Institute, Dokuz Eylul University; İzmir, Department of Basic
2
Oncology, Institute of Oncology, Dokuz Eylul University, İzmir, TURKEY

Background: Flap endonuclease 1 (FEN1) involves in DNA replication, long-patch excision repair, and
telomere maintenance. FEN1 overexpression has been reported to be associated with the different types
of cancers and it might be a predictive biomarker and therapeutic target in some cancers. But still there is
no pan-cancer analysis available now. Materials and methods: Through analysis of 33 types of tumors based
on the datasets of TCGA and GEO, we conduct the FEN1 gene expression analysis through TIMER2, then
based on the CPTAC dataset, we analyzed the total protein expression level of FEN1 between normal tissue
and primary tissue of breast cancer, ovarian cancer, colon cancer, clear cell RCC and UCEC. FEN1 genetic
alteration evaluated by using cBioPortal web and survival status analyzed with GEPIA2. Results: Fen1 is
highly expressed in most cancers (Fig.1,2). Highly expressed FEN1 was linked to poor prognosis of overall
Survival for cancers of LIHC (p=0.007), KICH(p=0.039), ACC(p=0.007), PAAD(p=0.014), MESO(p=0.002),
LGG(p=0.019), UVM(p=0.014) and LUAD(p=0.007), while low expression is poor prognosis only in
THYM(p=0.04) within the TCGA (Fig.3). The genetic alteration status of FEN1 in different tumor samples of
the TCGA cohorts were observed. The highest alteration frequency of FEN1 (> 8%) appeared with primary
Cholangiocarcinoma with “CNA amplification” and nearly 5,26% in uterine carcinosarcomas. The
“mutation” type was the primary Uterine Corpus Endometrial Carcinomas, which show an alteration
frequency of ~3,51% (Fig.4). Conclusion: It seems FEN1 play a common molecular pathway in the
pathogenesis of different tumors. But still remains to be answered. Our pan-cancer study provides a
relatively comprehensive understanding of the roles of FEN1 in different tumorigenesis.

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