Role and possible mechanism of pseudogene FMO6P in inhibiting invasion and metastasis of gastric cancer

doi:10.16139/j.1007-9610.2024.02.12

Abstract

Abstract:

Objective To determine the expression and clinical significance of pseudogene FMO6P in gastric cancer, and explore its functions and underlying molecular mechanism in regulating the invasion and metastasis of gastric cancer cells. Methods The expression level of FMO6P in gastric cancer tissues and cell lines was detected by quantitative real time polymerase chain reaction(qRT-PCR). The migration and invasion abilities of gastric cancer cells were detected by transwell assay. The effect of FMO6P on the tumor formation and peritoneal dissemination of gastric cancer cells were evaluated by injecting FMO6P-overexpressing gastric cancer cells into the subcutaneous or peritoneal cavity of nude mice respectively. The expression levels of epithelial-mesenchymal transition(EMT) markers, including E-cadherin, N-cadherin, ZEB1, MMP2, and the activation of AKT/mTOR pathway in FMO6P-overexpressing or knockdown gastric cancer cells were measured by Western blot. Results The expression of FMO6P was significantly reduced in tumor tissues compared to its adjacent non-tumor tissues of gastric cancer, FMO6P expression level in tumor tissues was correlated with tumor size and TNM stage. Overexpression of FMO6P significantly inhibited the invasion and migration abilities of gastric cancer cells, while downregulation of FMO6P expression promoted the invasion and migration ability of gastric cancer cells. Overexpression of FMO6P in gastric cancer cells significantly inhibited the subcutaneous tumor formation and peritoneal dissemination of gastric cancer cells in nude mice. Moreover, overexpression of FMO6P promoted the expression of E-cadherin, and inhibited the expression of N-cadherin, ZEB1, and MMP2 in gastric cancer cells. The phosphorylation levels of AKT and mTOR were also downregulated in gastric cancer cells overexpressing FMO6P. Conclusion All these findings suggested that pseudogene FMO6P suppresses the invasion and migration potential of gastric cancer cells in vitro and in vivo, which is possibly through the inhibition of the AKT/mTOR signaling pathway.

Key words: Gastric cancer, Pseudogene, FMO6P, Tumor metastasis

CLC Number:

R735.2

WU Xiongyan, LI Zhen, YU Zhenjia, SU liping. Role and possible mechanism of pseudogene FMO6P in inhibiting invasion and metastasis of gastric cancer[J]. Journal of Surgery Concepts & Practice, 2024, 29(02): 161-169.

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References 31

[1]	YANG L, ZHENG R S, WANG N, et al. Incidence and mortality of stomach cancer in China 2014[J]. Chin J Cancer Res, 2018, 30(3):291-298.
[2]	MIGUEL V, LAMAS S, ESPINOSA-DIEZ C. Role of non-coding-RNAs in response to environmental stressors and consequences on human health[J]. Redox Biol, 2020,37:101580.
[3]	XIAO-JIE L, AI-MEI G, LI-JUAN J, et al. Pseudogene in cancer:real functions and promising signature[J]. J Med Genet, 2015, 52(1):17-24.
[4]	MA H W, MA T S, CHEN M, et al. The pseudogene-derived long non-coding RNA SFTA1P suppresses cell proliferation,migration,and invasion in gastric cancer[J]. Biosci Rep, 2018, 38(2):BSR20171193.
[5]	LI D D, SHE J J, HU X H, et al. The ELF3-regulated lncRNA UBE2CP3 is over-stabilized by RNA-RNA interactions and drives gastric cancer metastasis via miR-138-5p/ITGA2 axis[J]. Oncogene, 2021, 40(35):5403-5415.
[6]	GUO Y M, WANG Y M, MA Y L, et al. Upregulation of lncRNA SUMO1P3 promotes proliferation, invasion and drug resistance in gastric cancer through interacting with the CNBP protein[J]. RSC Adv, 2020, 10(10):6006-6016. doi: 10.1039/c9ra09497k pmid: 35497433
[7]	XU Y C, YU Y, WEI C C, et al. Over-expression of oncigenic pesudogene DUXAP10 promotes cell proliferation and invasion by regulating LATS1 and beta-catenin in gastric cancer[J]. J Exp Clin Cancer Res, 2018, 37(1):13.
[8]	HERNANDEZ D, JANMOHAMED A, CHANDAN P, et al. Organization and evolution of the flavin-containing monooxygenase genes of human and mouse:identification of novel gene and pseudogene clusters[J]. Pharmacogene-tics, 2004, 14(2):117-130.
[9]	FIORENTINI F, GEIER M, BINDA C, et al. Biocatalytic characterization of human FMO5: unearthing baeyer-villiger reactions in humans[J]. ACS Chem Biol, 2016, 11(4):1039-1048. doi: 10.1021/acschembio.5b01016 pmid: 26771671
[10]	LI H, YU B Q, LI J F, et al. Characterization of differentially expressed genes involved in pathways associated with gastric cancer[J]. PLoS One, 2015, 10(4):e0125013.
[11]	PASTUSHENKO I, BLANPAIN C. EMT transition states during tumor progression and metastasis[J]. Trends Cell Biol, 2019, 29(3):212-226. doi: S0962-8924(18)30201-0 pmid: 30594349
[12]	SAITOH M. Involvement of partial EMT in cancer progression[J]. J Biochem, 2018, 164(4):257-264. doi: 10.1093/jb/mvy047 pmid: 29726955
[13]	SINGH M, YELLE N, VENUGOPAL C, et al. EMT:mechanisms and therapeutic implications[J]. Pharmacol Ther, 2018,182:80-94.
[14]	FATTAHI S, AMJADI-MOHEB F, TABARIPOUR R, et al. PI3K/AKT/mTOR signaling in gastric cancer: epigenetics and beyond[J]. Life Sci, 2020,262:118513.
[15]	WANG X J, LI X D, LIN F K, et al. The lnc-CTSLP8 upregulates CTSL1 as a competitive endogenous RNA and promotes ovarian cancer metastasis[J]. J Exp Clin Cancer Res, 2021, 40(1):151. doi: 10.1186/s13046-021-01957-z pmid: 33933142
[16]	ZHANG L M, WANG P, LIU X M, et al. LncRNA SUMO1P3 drives colon cancer growth, metastasis and angiogenesis[J]. Am J Transl Res, 2017, 9(12):5461-5472.
[17]	WANG X H, ZHANG L H, LIANG Q Y, et al. DUSP5P1 promotes gastric cancer metastasis and platinum drug resistance[J]. Oncogenesis, 2022, 11(1):66. doi: 10.1038/s41389-022-00441-3 pmid: 36307394
[18]	BAKIR B, CHIARELLA A M, PITARRESI J R, et al. EMT,MET,plasticity,and tumor metastasis[J]. Trends Cell Biol, 2020, 30(10):764-776.
[19]	BAJ J, KORONA-GŁOWNIAK I, FORMA I, et al. Mechanisms of the epithelial-mesenchymal transition and tumor microenvironment in helicobacter pylori-induced gastric cancer[J]. Cells, 2020, 9(4):1055.
[20]	NOOROLYAI S, SHAJARI N, BAGHBANI E, et al. The relation between PI3K/AKT signalling pathway and cancer[J]. Gene, 2019, 698:120-128. doi: S0378-1119(19)30217-3 pmid: 30849534
[21]	YANG X, ZHU W. ERBB3 mediates the PI3K/AKT/mTOR pathway to alter the epithelial-mesenchymal transition in cervical cancer and predict immunity filtration outcome[J]. Exp Ther Med, 2023, 25(4):146.
[22]	LI H, GUAN B X, LIU S, et al. PTPN14 promotes gastric cancer progression by PI3KA/AKT/mTOR pathway[J]. Cell Death Dis, 2023, 14(3):188. doi: 10.1038/s41419-023-05712-4 pmid: 36898991
[23]	CHEN H R, ZHANG L F, ZUO M N, et al. Inhibition of apoptosis through AKT-mTOR pathway in ovarian cancer and renal cancer[J]. Aging(Albany NY), 2023, 15(4):1210-1227.
[24]	GHAREGHOMI S, ATABAKI V, ABDOLLAHZADEH N, et al. Bioactive PI3-kinase/Akt/mTOR inhibitors in targeted lung cancer therapy[J]. Adv Pharm Bull, 2023, 13(1):24-35. doi: 10.34172/apb.2023.003 pmid: 36721812
[25]	WANG H W, CHEN Y J, YUAN Q Z, et al. HRK inhibits colorectal cancer cells proliferation by suppressing the PI3K/AKT/mTOR pathway[J]. Front Oncol, 2022,12:1053510.
[26]	LI P, ZHANG Z, LV H, et al. Inhibiting the expression of STARD3 induced apoptosis via the inactivation of PI3K/AKT/mTOR pathway on ER(+) breast cancer[J]. Tissue Cell, 2022,79:101971.
[27]	PETERSON R T, BEAL P A, COMB M J, et al. FKBP12-rapamycin-associated protein (FRAP) autophosphorylates at serine 2481 under translationally repressive conditions[J]. J Biol Chem, 2000, 275(10):7416-7423. doi: 10.1074/jbc.275.10.7416 pmid: 10702316
[28]	NAVÉ B T, OUWENS M, WITHERS D J, et al. Mammalian target of rapamycin is a direct target for protein kinase B: identification of a convergence point for opposing effects of insulin and amino-acid deficiency on protein translation[J]. Biochem J, 1999, 344 Pt 2(Pt 2):427-431.
[29]	WANG C, YANG Z, XU E, et al. Apolipoprotein C-Ⅱ induces EMT to promote gastric cancer peritoneal metastasis via PI3K/AKT/mTOR pathway[J]. Clin Transl Med, 2021, 11(8):e522.
[30]	WANG J, JIANG C H, LI N, et al. The circEPSTI1/mir-942-5p/LTBP2 axis regulates the progression of OSCC in the background of OSF via EMT and the PI3K/Akt/mTOR pathway[J]. Cell Death Dis, 2020, 11(8):682.
[31]	MA Z, LOU S P, JIANG Z. PHLDA2 regulates EMT and autophagy in colorectal cancer via the PI3K/AKT signa-ling pathway[J]. Aging(Albany NY), 2020, 12(9):7985-8000.

	Expression of FMO6P		χ²/Z/t value	P value
	High(n=11)	Low(n=69)	χ²/Z/t value	P value
Gender			0.695	0.404
Male	9	48
Female	2	21
Age			0.155	0.693
> 60 years	7	48
≤ 60 years	4	21
Tumor diameter (cm)			8.449	0.003
> 5	5	58
≤ 5	6	11
Pathological T stage			9.323	0.002
T1, T2	8	8
T3, T4	11	61
Pathological N stage			1.382	0.239
-	2	25
+	9	44
Metastasis			0.949	0.330
-	9	63
+	2	6
TNM stage			4.071	0.043 6
Ⅰ+Ⅱ	1	28
Ⅲ+Ⅳ	10	41