CircMALAT1 promotes cancer stem-like properties and chemoresistance via regulating Musashi-2/c-Myc axis in esophageal squamous cell carcinoma

Abstract

The primary challenge in treating esophageal squamous cell carcinoma (ESCC) is resistance to chemotherapy. Cancer stem cell (CSC) is the root cause of tumor drug resistance. Therefore, targeting CSCs has been considered promising therapeutic strategy for tumor treatment. Here, we report that circMALAT1 was significantly upregulated in ESCC CSC-like cells and primary tumors from ESCC patients. Clinically, there was a positive correlation between circMALAT1 expression and ESCC stage and lymph node metastasis, as well as poor prognosis for ESCC patients. In vitro and in vivo functional studies revealed that circ-MALAT1 promoted CSC-like cells expansion, tumor growth, lung metastasis and drug resistance of ESCC. Mechanistically, circMALAT1 directly interacted with CSC-functional protein Musashi RNA Binding Protein 2 (MSI2). Circ-MALAT1 inhibited MSI2 ubiquitination by preventing it from interacting with β-transducin repeat containing protein (BTRC) E3 ubiquitin ligase. Also, circ-MALAT1 knockdown inhibited the expression of MSI2-regulating CSC-markers c-Myc in ESCC. Collectively, circMALAT1 modulated the ubiquitination and degradation of the MSI2 protein signaling with ESCC CSCs and accelerated malignant progression of ESCC. CircMALAT1 has the potential to serve as a biomarker for drug resistance and as a target for therapy in CSCs within ESCC.

Keywords

cancer stem cell (CSC) / circMALAT1 / drug resistance / esophageal squamous cell carcinoma (ESCC) / Musashi RNA binding protein 2 (MSI2)

References

1	H Sung, J Ferlay, RL Siegel, et al. Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2021;71(3):209-249.
2	CC Abnet, M Arnold, WQ Wei. Epidemiology of esophageal squamous cell carcinoma. Gastroenterology. 2018;154(2):360-373.
3	T Kojima, MA Shah, K Muro, et al. Randomized Phase III KEYNOTE-181 study of pembrolizumab versus chemotherapy in advanced esophageal cancer. J Clin Oncol. 2020;38(35):4138-4148.
4	L Gong, M Bai, L Dai, et al. CACA guidelines for holistic integrative management of esophageal carcinoma. Holist Integr Oncol. 2023;2:34.
5	H Yang, H Liu, Y Chen, et al. Long-term efficacy of neoadjuvant chemoradiotherapy plus surgery for the treatment of locally advanced esophageal squamous cell carcinoma: the NEOCRTEC5010 randomized clinical trial. JAMA Surg. 2021;156(8):721-729.
6	Y Song, L Li, Y Ou, et al. Identification of genomic alterations in oesophageal squamous cell cancer. Nature. 2014;509(7498):91-95.
7	L Yang, P Shi, G Zhao, et al. Targeting cancer stem cell pathways for cancer therapy. Signal Transduct Target Ther. 2020;5(1):8.
8	T Huang, X Song, D Xu, et al. Stem cell programs in cancer initiation, progression, and therapy resistance. Theranostics. 2020;10(19):8721-8743.
9	JA Clara, C Monge, Y Yang, N Takebe. Targeting signalling pathways and the immune microenvironment of cancer stem cells—a clinical update. Nat Rev Clin Oncol. 2020;17(4):204-232.
10	Y Li, Z Wang, JA Ajani, S Song. Drug resistance and Cancer stem cells. Cell Commun Signal. 2021;19(1):19.
11	Y Garcia-Mayea, C Mir, F Masson, R Paciucci, ME LL. Insights into new mechanisms and models of cancer stem cell multidrug resistance. Semin Cancer Biol. 2020;60:166-180.
12	S Prasad, S Ramachandran, N Gupta, I Kaushik, SK Srivastava. Cancer cells stemness: a doorstep to targeted therapy. Biochim Biophys Acta Mol Basis Dis. 2020;1866(4):165424.
13	L Chen, G Shan. CircRNA in cancer: fundamental mechanism and clinical potential. Cancer Lett. 2021;505:49-57.
14	LS Kristensen, MS Andersen, LVW Stagsted, KK Ebbesen, TB Hansen, J Kjems. The biogenesis, biology and characterization of circular RNAs. Nat Rev Genet. 2019;20(11):675-691.
15	CX Liu, LL Chen. Circular RNAs: characterization, cellular roles, and applications. Cell. 2022;185(12):2016-2034.
16	IL Patop, S Wust, S Kadener. Past, present, and future of circRNAs. EMBO J. 2019;38(16):e100836.
17	LS Kristensen, T Jakobsen, H Hager, J Kjems. The emerging roles of circRNAs in cancer and oncology. Nat Rev Clin Oncol. 2022;19(3):188-206.
18	LL Chen. The expanding regulatory mechanisms and cellular functions of circular RNAs. Nat Rev Mol Cell Biol. 2020;21(8):475-490.
19	X Li, L Yang, LL Chen. The biogenesis, functions, and challenges of circular RNAs. Mol Cell. 2018;71(3):428-442.
20	S Misir, N Wu, BB Yang. Specific expression and functions of circular RNAs. Cell Death Differ. 2022;29(3):481-491.
21	Y Gu, Y Wang, L He, et al. Circular RNA circIPO11 drives self-renewal of liver cancer initiating cells via Hedgehog signaling. Mol Cancer. 2021;20(1):132.
22	L Chen, R Kong, C Wu, et al. Circ-MALAT1 functions as both an mRNA translation brake and a microRNA sponge to promote self-renewal of hepatocellular cancer stem cells. Adv Sci (Weinh). 2020;7(4):1900949.
23	X Wang, W Sun, W Shen, et al. Long non-coding RNA DILC regulates liver cancer stem cells via IL-6/STAT3 axis. J Hepatol. 2016;64(6):1283-1294.
24	TK Lee, VC Cheung, P Lu, et al. Blockade of CD47-mediated cathepsin S/protease-activated receptor 2 signaling provides a therapeutic target for hepatocellular carcinoma. Hepatology. 2014;60(1):179-191.
25	Y Zhu, B Zhou, X Hu, et al. LncRNA LINC00942 promotes chemoresistance in gastric cancer by suppressing MSI2 degradation to enhance c-Myc mRNA stability. Clin Transl Med. 2022;12(1):e703.
26	J Taggart, TC Ho, E Amin, et al. MSI2 is required for maintaining activated myelodysplastic syndrome stem cells. Nat Commun. 2016;7:10739.
27	D Hanahan. Hallmarks of cancer: new dimensions. Cancer Discov. 2022;12(1):31-46.
28	L Garcia-Martinez, Y Zhang, Y Nakata, HL Chan, L Morey. Epigenetic mechanisms in breast cancer therapy and resistance. Nat Commun. 2021;12(1):1786.
29	S Hussain, S Tulsyan, SA Dar, et al. Role of epigenetics in carcinogenesis: recent advancements in anticancer therapy. Semin Cancer Biol. 2022;83:441-451.
30	L Guo, YT Lee, Y Zhou, Y Huang. Targeting epigenetic regulatory machinery to overcome cancer therapy resistance. Semin Cancer Biol. 2022;83:487-502.
31	GP Nagaraju, B Farran, T Luong, BF El-Rayes. Understanding the molecular mechanisms that regulate pancreatic cancer stem cell formation, stemness and chemoresistance: a brief overview. Semin Cancer Biol. 2023;88:67-80.
32	O Hen, D Barkan. Dormant disseminated tumor cells and cancer stem/progenitor-like cells: similarities and opportunities. Semin Cancer Biol. 2020;60:157-165.
33	T Shibue, RA Weinberg. EMT, CSCs, and drug resistance: the mechanistic link and clinical implications. Nat Rev Clin Oncol. 2017;14(10):611-629.
34	S Adhikari, A Bhattacharya, S Adhikary, et al. The paradigm of drug resistance in cancer: an epigenetic perspective. Biosci Rep. 2022;42(4):BSR20211812.
35	P Nallasamy, RK Nimmakayala, S Parte, AC Are, SK Batra, MP Ponnusamy. Tumor microenvironment enriches the stemness features: the architectural event of therapy resistance and metastasis. Mol Cancer. 2022;21(1):225.
36	N Jing, WQ Gao, YX Fang. Regulation of formation, stemness and therapeutic resistance of cancer stem cells. Front Cell Dev Biol. 2021;9:641498.
37	SD Huang, Y Yuan, XH Liu, et al. Self-renewal and chemotherapy resistance of p75NTR positive cells in esophageal squamous cell carcinomas. BMC Cancer. 2009;9:9.
38	F Islam, V Gopalan, R Wahab, RA Smith, AK Lam. Cancer stem cells in oesophageal squamous cell carcinoma: identification, prognostic and treatment perspectives. Crit Rev Oncol Hematol. 2015;96(1):9-19.
39	D Hang, HC Dong, T Ning, B Dong, DL Hou, WG Xu. Prognostic value of the stem cell markers CD133 and ABCG2 expression in esophageal squamous cell carcinoma. Dis Esophagus. 2012;25(7):638-644.
40	W Wang, S He, R Zhang, et al. ALDH1A1 maintains the cancer stem-like cells properties of esophageal squamous cell carcinoma by activating the AKT signal pathway and interacting with beta-catenin. Biomed Pharmacother. 2020;125:109940.
41	XY Ming, L Fu, LY Zhang, et al. Integrin alpha7 is a functional cancer stem cell surface marker in oesophageal squamous cell carcinoma. Nat Commun. 2016;7:13568.
42	MY Li, LN Fan, DH Han, et al. Ribosomal S6 protein kinase 4 promotes radioresistance in esophageal squamous cell carcinoma. J Clin Invest. 2020;130(8):4301-4319.
43	MW Hentze, A Castello, T Schwarzl, T Preiss. A brave new world of RNA-binding proteins. Nat Rev Mol Cell Biol. 2018;19(5):327-341.
44	AE Kudinov, J Karanicolas, EA Golemis, Y Boumber. Musashi RNA-binding proteins as cancer drivers and novel therapeutic targets. Clin Cancer Res. 2017;23(9):2143-2153.
45	C Qu, L He, N Yao, et al. Myofibroblast-specific Msi2 knockout inhibits HCC progression in a mouse model. Hepatology. 2021;74(1):458-473.
46	H Zou, J Luo, Y Guo, et al. RNA-binding protein complex LIN28/MSI2 enhances cancer stem cell-like properties by modulating Hippo-YAP1 signaling and independently of Let-7. Oncogene. 2022;41(11):1657-1672.
47	Z Li, H Jin, G Mao, L Wu, Q Guo. Msi2 plays a carcinogenic role in esophageal squamous cell carcinoma via regulation of the Wnt/beta-catenin and Hedgehog signaling pathways. Exp Cell Res. 2017;361(1):170-177.
48	AE Kudinov, A Deneka, AS Nikonova, et al. Musashi-2 (MSI2) supports TGF-beta signaling and inhibits claudins to promote non-small cell lung cancer (NSCLC) metastasis. Proc Natl Acad Sci USA. 2016;113(25):6955-6960.
49	Y Nishimoto, H Okano. New insight into cancer therapeutics: induction of differentiation by regulating the Musashi/Numb/Notch pathway. Cell Res. 2010;20(10):1083-1085.
50	S Duggimpudi, A Kloetgen, SK Maney, et al. Transcriptome-wide analysis uncovers the targets of the RNA-binding protein MSI2 and effects of MSI2's RNA-binding activity on IL-6 signaling. J Biol Chem. 2018;293(40):15359-15369.
51	L Zheng, Z Zhao, L Rong, L Xue, Y Song. RASSF6-TRIM16 axis promotes cell proliferation, migration and invasion in esophageal squamous cell carcinoma. J Genet Genomics. 2019;46(10):477-488.