AF9 sustains glycolysis in colorectal cancer via H3K9ac-mediated PCK2 and FBP1 transcription

Xuefeng He; Xinyang Zhong; Yi Fang; Zijuan Hu; Zhiyu Chen; Yaxian Wang; Huixia Huang; Senlin Zhao; Dawei Li; Ping Wei

doi:10.1002/ctm2.1352

AF9 sustains glycolysis in colorectal cancer via H3K9ac-mediated PCK2 and FBP1 transcription

Clin Transl Med. 2023 Aug;13(8):e1352. doi: 10.1002/ctm2.1352.

Authors

Xuefeng He^{1

2}, Xinyang Zhong^{1

2}, Yi Fang³, Zijuan Hu^{4

5

6

2}, Zhiyu Chen^{2

7}, Yaxian Wang^{1

2}, Huixia Huang^{4

5

6

2}, Senlin Zhao^{1

2}, Dawei Li^{1

2}, Ping Wei^{4

5

6

2}

Affiliations

¹ Department of Colorectal Surgery, Fudan University Shanghai Cancer Center, Shanghai, China.
² Department of Oncology, Shanghai Medical College Fudan University, Shanghai, China.
³ Emergency Department, Shanghai Tenth People's Hospital, Shanghai, China.
⁴ Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China.
⁵ Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China.
⁶ Institute of Pathology, Fudan University, Shanghai, China.
⁷ Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.

Abstract

Background: The tumourigenesis of various cancers is influenced by epigenetic deregulation. Among 591 epigenetic regulator factors (ERFs) examined, AF9 showed significant inhibition of malignancy in colorectal cancer (CRC) based on our wound healing assays. However, the precise role of AF9 in CRC remains to be explored.

Methods: To investigate the function of AF9 in CRC, we utilised small interfering RNAs (siRNAs) to knock down the expression of 591 ERFs. Subsequently, we performed wound healing assays to evaluate cell proliferation and migration. In vitro and in vivo assays were conducted to elucidate the potential impact of AF9 in CRC. Clinical samples were analysed to assess the association between AF9 expression and CRC prognosis. Additionally, an Azoxymethane-Dextran Sodium Sulfate (AOM/DSS) induced CRC AF9^IEC-/- mouse model was employed to confirm the role of AF9 in CRC. To identify the target gene of AF9, RNA-seq and coimmunoprecipitation analyses were performed. Furthermore, bioinformatics prediction was applied to identify potential miRNAs that target AF9.

Results: Among the 591 ERFs examined, AF9 exhibited downregulation in CRC and showed a positive correlation with prolonged survival in CRC patients. In vitro and in vivo assays proved that depletion of AF9 could promote cell proliferation, migration as well as glycolysis. Specifically, knockout of MLLT3 (AF9) in intestinal epithelial cells significantly increased tumour formation induced by AOM/DSS. We also identified miR-145 could target 3'untranslated region of AF9 to suppress AF9 expression. Loss of AF9 led to decreased expression of gluconeogenic genes, including phosphoenolpyruvate carboxykinase 2 (PCK2) and fructose 1,6-bisphosphatase 1 (FBP1), subsequently promoting glucose consumption and tumourigenesis.

Conclusions: AF9 is essential for the upregulation of PCK2 and FBP1, and the disruption of the miR-145/AF9 axis may serve as a potential target for the development of CRC therapeutics.

Keywords: AF9; colorectal cancer; glucogenesis; miR-145.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Carcinogenesis / genetics
Cell Transformation, Neoplastic / genetics
Colorectal Neoplasms* / pathology
Glycolysis / genetics
Mice
MicroRNAs* / genetics
MicroRNAs* / metabolism
RNA, Small Interfering / metabolism

Substances

MicroRNAs
RNA, Small Interfering
PCK2 protein, human
FBP1 protein, human
MLLT3 protein, human