Research Paper Volume 13, Issue 17 pp 21497—21512

m6A demethylase ALKBH5 suppression contributes to esophageal squamous cell carcinoma progression

Dong Xiao1,2,3,5, *, , Ting-Xiao Fang4, *, , Ye Lei1,2,3, *, , Sheng-Jun Xiao6, *, , Jia-Wei Xia7, *, , Tao-Yan Lin3,8, , Yong-Long Li1,2,3, , Jian-Xue Zhai4, , Xiao-Yan Li1,2, , Shi-Hao Huang3, , Jun-Shuang Jia3, , Yu-Guang Tian1,2, , Xiao-Lin Lin3, , Kai-Can Cai4, &, , Yan Sun9, ,

  • 1 Laboratory Animal Center, Southern Medical University, Guangzhou 510515, China
  • 2 Guangzhou Southern Medical Laboratory Animal Sci. & Tech. Co., Ltd., Guangzhou 510515, China
  • 3 Guangzhou Key Laboratory of Tumor Immunology Research, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
  • 4 Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
  • 5 National Demonstration Center for Experimental Education of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
  • 6 Department of Pathology, The Second Affiliated Hospital, Guilin Medical University, Guilin 541199, China
  • 7 The Third People’s Hospital of Kunming, The Sixth Affiliated Hospital of Dali University, Kunming 650041, China
  • 8 Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
  • 9 Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China
* Equal contribution

Received: March 29, 2021       Accepted: August 13, 2021       Published: September 7, 2021
How to Cite

Copyright: © 2021 Xiao et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Esophageal squamous cell carcinoma (ESCC) is a highly malignant gastrointestinal cancer with a high recurrence rate and poor prognosis. Although N6-methyladenosine (m6A), the most abundant epitranscriptomic modification of mRNAs, has been implicated in several cancers, little is known about its participation in ESCC progression. We found reduced expression of ALKBH5, an m6A demethylase, in ESCC tissue specimens with a more pronounced effect in T3-T4, N1-N3, clinical stages III–IV, and histological grade III tumors, suggesting its involvement in advanced stages of ESCC. Exogenous expression of ALKBH5 inhibited the in vitro proliferation of ESCC cells, whereas depletion of endogenous ALKBH5 markedly enhanced ESCC cell proliferation in vitro. This suggests ALKBH5 exerts anti-proliferative effects on ESCC growth. Furthermore, ALKBH5 overexpression suppressed tumor growth of Eca-109 cells in nude mice; conversely, depletion of endogenous ALKBH5 accelerated tumor growth of TE-13 cells in vivo. The growth-inhibitory effects of ALKBH5 overexpression are partly attributed to a G1-phase arrest. In addition, ALKBH5 overexpression reduced the in vitro migration and invasion of ESCC cells. Altogether, our findings demonstrate that the loss of ALKBH5 expression contributes to ESCC malignancy.


ATCC: American Type Culture Collection; DMEM: Dulbecco’s modified Eagle’s medium; ECL: enhanced chemiluminescence; ESCC: esophageal squamous cell carcinoma; FBS: fetal bovine serum; H&E: hematoxylin and eosin; m6A: N6-methyladenosine; IHC: immunohistochemistry; IRB: institutional review board; PFA: paraformaldehyde; PVDF: polyvinylidene difluoride; qRT-PCR: quantitative real-time polymerase chain reaction; RNAi: RNA interference; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; shRNA: short-hairpin RNA; SP: streptavidin-peroxidase; TMA: tissue microarray.