An Axis between the Long Non-Coding RNA HOXA11-AS and NQOs Enhances Metastatic Ability in Oral Squamous Cell Carcinoma.

Abstract

Long non-coding RNAs (lncRNAs) play critical roles in human cancers. HOXA11 anti-sense RNA (HOXA11-AS) is an lncRNA belonging to the homeobox (HOX) gene cluster that promotes liver metastasis in human colon cancer. However, its role and mechanism of action in human oral squamous cell carcinoma (OSCC) are unclear. In this study, we investigated HOXA11-AS expression and function in human OSCC tissues and cell lines, as well as a mouse model of OSCC. Our analyses showed that HOXA11-AS expression in human OSCC cases correlates with lymph node metastasis, nicotinamide adenine dinucleotide (NAD)(P)H: quinone oxidoreductase 1 (NQO1) upregulation, and dihydronicotinamide riboside (NRH): quinone oxidoreductase 2 (NQO2) downregulation. Using the human OSCC cell lines HSC3 and HSC4, we demonstrate that HOXA11-AS promotes NQO1 expression by sponging microRNA-494. In contrast, HOXA11-AS recruits zeste homolog 2 (EZH2) to the NQO2 promoter to suppress its expression via the trimethylation of H3K27. The upregulation of NQO1 enzymatic activity by HOXA11-AS results in the consumption of flavin adenine dinucleotide (FAD), which reduces FAD-requiring glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity and suppresses glycolysis. However, our analyses show that lactic acid fermentation levels are preserved by glutaminolysis due to increased malic enzyme-1 expression, promoting enhanced proliferation, invasion, survival, and drug resistance. In contrast, suppression of NQO2 expression reduces the consumption of NRH via NQO2 enzymatic activity and increases NAD levels, which promotes enhanced stemness and metastatic potential. In mouse tumor models, knockdown of HOXA11-AS markedly suppressed tumor growth and lung metastasis. From these findings, targeting HOXA11-AS may strongly suppress high-grade OSCC by regulating both NQO1 and NQO2.

• Authors: Chie Nakashima, Rina Fujiwara-Tani, Shiori Mori, Shingo Kishi, Hitoshi Ohmori, Kiyomu Fujii, Takuya Mori, Yoshihiro Miyagawa, Kazuhiko Yamamoto, Tadaaki Kirita, Yi Luo, Hiroki Kuniyasu
• Journal: International journal of molecular sciences (Int J Mol Sci) Vol. 23 Issue 18 (Sep 14 2022) ISSN: 1422-0067 [Electronic] Switzerland
• PMID: 36142607 (Publication Type: Journal Article)

Chemical References

• HOXA11 protein, human
• Homeodomain Proteins
• MIRN494 microRNA, human
• MicroRNAs
• Mirn494 microRNA, mouse
• Quinones
• RNA, Antisense
• RNA, Long Noncoding
• NAD
• Flavin-Adenine Dinucleotide
• Lactic Acid
• Glyceraldehyde-3-Phosphate Dehydrogenases
• NAD(P)H Dehydrogenase (Quinone)
• NQO1 protein, human
• NRH - quinone oxidoreductase2
• Quinone Reductases

Topics

• Animals
• Carcinoma, Squamous Cell (genetics, pathology)
• Cell Line, Tumor
• Cell Proliferation
• Flavin-Adenine Dinucleotide (genetics)
• Genes, Homeobox
• Glyceraldehyde-3-Phosphate Dehydrogenases (genetics)
• Homeodomain Proteins (metabolism)
• Humans
• Lactic Acid
• Mice
• MicroRNAs (genetics)
• Mouth Neoplasms (genetics, pathology)
• NAD (genetics)
• NAD(P)H Dehydrogenase (Quinone) (metabolism)
• Quinone Reductases (metabolism)
• Quinones
• RNA, Antisense
• RNA, Long Noncoding (genetics, metabolism)
• Squamous Cell Carcinoma of Head and Neck (genetics)