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Hepatocellular carcinoma (HCC) is a fatal digestive system cancer with unclear pathogenesis. M-phase phosphoprotein 8 (MPP8) has been shown to play a vital role in several cancer types, such as non-small cell lung cancer, gastric cancer and melanoma; however, there have been no studies into its role in HCC. The present study aimed to evaluate the role of MPP8 in regulating malignant phenotypes of liver cancer cells, and to further investigate the underlying mechanism. Bioinformatics analysis was performed to analyze related data from a public database, and to predict the potential microRNAs (miRNAs) that might target MPP8 mRNA; reverse transcription-quantitative PCR was used to measure the levels of mRNA and miRNA; western blotting was employed to detect protein levels; Cell Counting Kit-8 (CCK-8) and plate colony formation assays, wound healing assay and Transwell invasion assay were performed to evaluate the ability of cell proliferation, migration and invasion, respectively; dual-luciferase reporter gene assay was performed to identify the target association. The results showed that MPP8 was a risk factor for the survival of patients with HCC, and was up-regulated in HCC tissue samples and cell lines; MPP8 knockdown inhibited the proliferation, migration and invasion of liver cancer cells; MPP8 knockdown suppressed the PI3K/Akt pathway, and activation of this pathway reversed the inhibited liver cancer cell phenotypes by down-regulating MPP8; miR-576-3p, which was low in liver cancer cells, negatively regulated MPP8 expression by directly targeting its mRNA; up-regulating MPP8 expression reversed the inhibited signaling pathway and malignant phenotypes of liver cancer cells by miR-576-3p overexpression. In conclusion, the miR-576-3p/MPP8 axis regulates the proliferation, migration, and invasion of liver cancer cells through the PI3K/Akt signaling pathway. These findings lead novel insights into HCC progression, and propose MPP8 as a potential therapeutic target for HCC. [ABSTRACT FROM AUTHOR]

A previous study demonstrated that nicotinamide N‑methyltransferase (NNMT) is upregulated in the tissues of patients with prostate cancer (PCa); however, the specific underlying mechanism of this remains unclear. To begin with, the expression of NNMT was investigated in the peripheral blood of patients with PCa and of healthy control subjects. The results indicated that the expression level of NNMT was elevated in the peripheral blood and tissues of patients with PCa. Furthermore, the overexpression of NNMT enhanced PC‑3 cell viability, invasion and migration capacity. Additionally, the overexpression of NNMT significantly increased the mRNA level of sirtuin 1 (SIRT1) in PC‑3 cells. In addition, nicotinamide treatment significantly suppressed the expression of SIRT1 even in PC‑3 cells transfected with adeno‑associated virus‑NNMT. Furthermore, the PC‑3 cell invasion capacity was notably decreased by the nicotinamide treatment; however, such effects were largely abolished by the overexpression of NNMT in PC‑3 cells. These data indicated that NNMT enhanced PC‑3 cell migration and invasion mainly by regulating SIRT1 expression. In summary, the present study indicated that NNMT is an important regulator of SIRT1 expression in PC‑3 cells and may be a potential therapeutic target for PCa. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that increased expression of the alpha subunit of nuclear transcription factor Y (NF-YA) is associated with the malignant phenotype of various tumors. However, whether elevated expression of NF-YA promotes a malignant phenotype in osteosarcoma (OS), and the molecular mechanisms underlying this predicted effect is currently unknown. In the present study, small hairpin RNA (shRNA)-mediated knockdown of endogenous NF-YA significantly inhibited the migration and invasion capabilities of OS cells in vitro, whereas ectopic expression of NF-YA increased the migration and invasion capabilities of these cells. In addition, the induction of upregulated NF-YA expression on the malignant phenotype of OS cells was attenuated by silencing fatty acid synthase (FASN) expression. Furthermore, the expression level of FASN was increased by upregulating NF-YA, while decreased FASN expression was observed following NF-YA silencing in OS cells. The results of the present study suggest that NF-YA may promote a malignant phenotype in OS cells, in part, by activating the FASN signaling pathway, which may represent a promising target for the management of OS. [ABSTRACT FROM AUTHOR]

The objective of the present study was to investigate whether cyclooxygenase-2 (COX-2) is associated with malignancy, and to investigate its molecular mechanisms in human lung cancer tumor malignancy. The present study used RNA interference (RNAi) methodology and celecoxib, a COX-2 inhibitor, to investigate the effect of COX-2 knockdown on the proliferation and invasion abilities of lung cancer cells and the molecular mechanisms involved. Human lung adenocarcinoma A549-si10 and LTEP-A2 cells transfected with a specific small interfering RNA (A549-si10 and LTEP-A2-si10, respectively) grew more slowly compared with parental cell lines and cells transfected with pU6. The colony formation of A549-si10 and LTEP-A2-si10 cells was also reduced. In addition, A549-si10 and LTEP-A2-si10 cells were characterized by decreased metastatic and invasive abilities. The proliferation and invasive potential of parental A549 and LTEP-A2 cells was inhibited following treatment with celecoxib. In vivo, a COX-2 knockdown resulted in a decrease of proliferation and reduction of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and endothelial growth factor receptor (EGFR) expression in A549 xenografts. In conclusion, the present study revealed that COX-2 plays a extremely important role in tumor growth, infiltration and metastasis via the regulation of VEGF, MMP-2 and EGRF expression. Therefore, COX-2 is a potential therapeutic target for lung cancer. [ABSTRACT FROM AUTHOR]

Heat shock protein (HSP) 20 belongs to the small HSP family and exhibits diverse functions, including tumor suppression, in addition to being a molecular chaperon, which is the classical property of HSPs. The present study aimed to examine the association between HSP20 expression and breast cancer (BC) progression in patients, and to explore the possible role of HSP20 in malignant phenotypes of BC cells. A series of experiments, including reverse transcription-quantitative PCR, western blotting, Cell Counting Kit-8 and flow cytometry, were performed. Data from Gene Expression Omnibus and Kaplan-Meier Plotter revealed that HSP20 expression was significantly downregulated in BC tissues, and patients with BC with lower HSP20 expression exhibited poorer recurrence-free survival. The data revealed that HSP20 was closely associated with the pathological tumor stage (P=0.015) and pathological tumor node metastasis (P=0.031) of patients with BC. Additionally, HSP20 expression was markedly decreased in BC cell lines. Exogenous overexpression of HSP20 inhibited proliferation and accelerated apoptosis of BC cells. These cells exhibited decreased migration and invasion when HSP20 was overexpressed. Furthermore, HSP20 overexpression suppressed the MAPK and AKT signaling pathways, as evidenced by the reduced phosphorylation levels of AKT, ERK, JNK and p38. Knockdown of HSP20 exerted the opposite effects. Notably, the AKT agonist, SC79, and the ERK agonist, LM22B-10, reversed the decrease in cell proliferation and migration induced by HSP20 overexpression. Overall, the data suggest that the decreased expression of HSP20 in BC tissues may be associated with disease progression. HSP20 also attenuated the malignant phenotype of BC cells and the inhibition of MAPK and AKT signaling may be associated with this effect. Therefore, HSP20 may be a potential prognostic marker or a candidate therapeutic target for BC. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that fatty acid synthase (FASN) is crucial in the carcinogenesis of various types of tumor. In addition, the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, which is closely associated with cellular metabolism, affects cancer biology. However, whether the malignant phenotype of osteosarcoma (OS) cells is regulated by the PI3K/Akt/FASN signaling pathway and how the PI3K family specific inhibitor, 2-(4-morpholinyl)-8-phenyl-chromone (LY294002) affects the malignant phenotype of OS cells remains to be elucidated. In the present study, U2-OS and MG-63 cells were treated with LY294002 and subsequently western blot analysis was used to examine Akt, p-Akt and FASN protein expression. Additionally, FASN mRNA was detected by reverse transcription quantitative polymerase chain reaction. MTT and fluorescence-activated cell sorting assays were used to assess proliferation and apoptosis. Migration and invasion were investigated using wound healing and transwell invasion assays. The results demonstrated that LY294002 suppressed the PI3K/Akt/FASN signaling pathway. However, the malignant phenotypes of OS cells mentioned above were significantly inhibited. The present results indicated that LY294002 inhibits the malignant phenotype of OS cells via modulation of the PI3K/Akt/FASN signaling pathway in vitro and may be a new therapeutic strategy for the management of OS. [ABSTRACT FROM AUTHOR]

Lung cancer is a major public health problem worldwide, with a high associated incidence and mortality. In the present study, novel epigenetic signatures were identified through genome-wide DNA methylation microarrays. The results revealed that tripartite motif containing 58 (TRIM58), a potential tumor suppressor gene exhibited high methylation and low expression in lung cancer tissue samples compared with normal tissues. Receiver operating characteristic curve analysis demonstrated that TRIM58 may be a promising early diagnostic indicator of lung cancer. In addition, the present study analyzed the role of TRIM58 in tumorigenesis and development in lung cancer A549 cells. Wound healing assay and transwell migration assay were used to investigate cell migration, and flow cytometry analysis was used to detect apoptosis. Silencing TRIM58 accelerated the proliferation and migration of lung cancer cells. In contrast, the overexpression of TRIM58 significantly inhibited the proliferation and migration of lung cancer cells and promoted apoptosis. Gene set enrichment analysis revealed that TRIM58 expression was negatively correlated with MYC targets, G2M checkpoints and the mTORC1 signaling pathway. These results of the present study suggested that TRIM58, a potential tumor suppressor gene may serve as a novel diagnostic biomarker and therapeutic target in human lung cancer. [ABSTRACT FROM AUTHOR]