Expression of Cytosolic Phospholipase A2 (cPLA2)-Arachidonic Acid (AA)-Cyclooxygenase-2 (COX-2) Pathway Factors in Lung Cancer Patients and Its Implication in Lung Cancer Early Detection and Prognosis.

BACKGROUND The aim of this study was to elucidate the involvement of cPLA2-AA-COX-2 pathway factors and their potential role in lung cancer early diagnosis and prognosis. MATERIAL AND METHODS We selected 80 lung cancer patients as the cancer group, and 30 normal patients were selected as the normal group. Serum contents of COX-2, cPLA2, COX-1, mPGES, PGE2, and PGI2 were measured, and mRNA levels of COX-2, cPLA2, COX-1, and mPGES in serum were determined. Spearman's P-test was used to analyze the correlation between expression of PGI2 and mPGES in serum and the clinical characteristics of these lung cancer patients. The factors affecting the prognosis lung cancer were analyzed by COX regression model. RESULTS The serum contents of COX-2, cPLA2, COX-1, mPGES, PGE2, and PGI2 in the cancer patient group were significantly higher (p<0.05) than in the normal group; after treatment, the serum contents of these factors were significantly decreased (p<0.05). However, distant metastasis had a significant effect on serum contents of mPGES and PGI2 (p<0.05), but not on the other factors. The mRNA levels of COX-2, cPLA2, COX-1, and mPGES in cancer patients were significantly higher than in normal patients. In addition, the 5-year survival rate of patients with high expression of mPGES and/or PGI2 was lower than that of the low expression group. Cox regression analysis showed that the expression of mPGES and PGI2 had statistical significance in predicting the prognosis of lung cancer. CONCLUSIONS The cPLA2-AA-COX-2 pathway is closely associated with lung cancer. These findings are important for clinical diagnosis of lung cancer.

Long non-coding RNA H19 promotes proliferation of Hodgkin's lymphoma via AKT pathway.

PURPOSE: To explore whether lncRNA (Long non-coding RNA) H19 could promote the development of Hodgkin's lymphoma (HL) by regulating cell proliferation via AKT pathway. METHODS: H19 expressions in 60 HL tissues, 40 RH (reactive hyperplasia of lymph nodes) tissues, L428, A20 and Ly1 cell lines were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). H19 siRNA and pcDNA-H19 were constructed. Cell viability after altering H19 expression was detected by EdU and cell counting kit-8 (CCK-8) assay. The mRNA level of AKT in HL tissues and RH tissues was detected by qRT-PCR. The relationship between AKT and H19 was further detected by Western blot. RESULTS: H19 was overexpressed in HL tissues and cell lines compared with those of controls. HL patients with huge lump and in Ann Arbor stage III-IV presented higher expression of H19. Besides, H19 expression was negatively correlated to overall survival (OS) of HL patients. In vitro experiments suggested that H19 downregulation decreased proliferation and viability of HL cells. AKT expression was upregulated in HL tissues compared with RH tissues, and was positively regulated by H19. Western blot results also indicated that H19 overexpression upregulated protein expression of AKT in HL cells. CONCLUSIONS: Overexpressed lncRNA H19 promotes HL development by stimulating proliferation of HL cells via AKT pathway.

Overexpression of Long Non-Coding RNA TUG1 Promotes Colon Cancer Progression.

BACKGROUND Colon cancer is one of the most prevalent and deadly cancers worldwide. It is still necessary to further define the mechanisms and explore therapeutic targets of colon cancer. Dysregulation of long noncoding RNAs (lncRNAs) has been shown to be correlated with diverse biological processes, including tumorigenesis. This study aimed to characterize the biological mechanism of taurine-upregulated gene 1 (TUG1) in colon cancer. MATERIAL AND METHODS qRT-PCR was used to analyze the expression level of TUG1 and p63 in 75 colon cancer tissues and the matched adjacent non-tumor tissue. In vitro, cultured colon cancer cell lines HCT-116 and LoVo were used as cell models. TUG1 and p63 were silenced via transferring siRNA into HCT-116 or LoVo. The effects of TUG1 were investigated by examining cell proliferation, apoptosis, and migration. RESULTS Among the 75 colon cancer cases, the expression of TUG1 was significantly higher in colon cancer tissues compared with the matched adjacent non-tumor tissue, while p63 expression was lower in the tumor tissue. In HCT-116 and LoVo, the expression of TUG1 was significantly increased by p63 siRNA transfection. Furthermore, down-regulation of TUG1 by siRNA significantly inhibited the cell proliferation and promoted colon cancer cell apoptosis. In addition, inhibition of TUG1 expression significantly blocked the cell migration ability of colon cancer cells. CONCLUSIONS LncRNA TUG1 may serve as a potential oncogene for colon cancer. Overexpressed TUG1 may contribute to promoting cell proliferation and migration in colon cancer cells.

[Retracted] MicroRNA-200c inhibits the metastasis of non-small cell lung cancer cells by targeting ZEB2, an epithelial-mesenchymal transition regulator.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the cell Transwell assay data in the article (featured in Figs. 2C and 4C) were strikingly similar to data appearing in different form in other articles by different authors at different research institutions, which were already under consideration for publication or had already been published elsewhere at the time of the present article's submission [C. Lai et al, 'MicroRNA­133a inhibits proliferation and invasion, and induces apoptosis in gastric carcinoma cells via targeting fascin actin­bundling protein 1', Mol Med Rep 12: 1473­1478, 2015; and Y. Shi et al, 'MicroRNA­204 inhibits proliferation, migration, invasion and epithelial­mesenchymal transition in osteosarcoma cells via targeting Sirtuin 1', Oncol Rep 34: 399­406, 2015]. Owing to the fact that the contentious data in the above article had already appeared in different form in other articles prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors did not reply to indicate whether or not they agreed with the retraction of the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 13: 3349-3355, 2016; DOI: 10.3892/mmr.2016.4901].

Long non-coding RNA H19 promotes proliferation of Hodgkin's lymphoma via AKT pathway.

PURPOSE: To explore whether lncRNA (Long non-coding RNA) H19 could promote the development of Hodgkin's lymphoma (HL) by regulating cell proliferation via AKT pathway. METHODS: H19 expressions in 60 HL tissues, 40 RH (reactive hyperplasia of lymph nodes) tissues, L428, A20 and Ly1 cell lines were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). H19 siRNA and pcDNA-H19 were constructed. Cell viability after altering H19 expression was detected by EdU and cell counting kit-8 (CCK-8) assay. The mRNA level of AKT in HL tissues and RH tissues was detected by qRT-PCR. The relationship between AKT and H19 was further detected by Western blot. RESULTS: H19 was overexpressed in HL tissues and cell lines compared with those of controls. HL patients with huge lump and in Ann Arbor stage III-IV presented higher expression of H19. Besides, H19 expression was negatively correlated to overall survival (OS) of HL patients. In vitro experiments suggested that H19 downregulation decreased proliferation and viability of HL cells. AKT expression was upregulated in HL tissues compared with RH tissues, and was positively regulated by H19. Western blot results also indicated that H19 overexpression upregulated protein expression of AKT in HL cells. CONCLUSIONS: Overexpressed lncRNA H19 promotes HL development by stimulating proliferation of HL cells via AKT pathway.

miR­338­3p suppresses the malignancy of T­cell lymphoblastic lymphoma by downregulating HOXA3.

T­cell lymphoblastic lymphoma (T­LBL) is an aggressive malignancy with poor prognosis due to frequent relapses. Previous studies have reported an association of the disease with abnormal chromosomal rearrangements, DNA copy number alterations and mutations in critical signaling factors, such as those in the Notch1 pathway; however, the molecular mechanisms underlying the development of the disease remain unclear, limiting the development of novel therapies. In the present study, gene expression was detected by qPCR and western blot analysis. Diagnostic analysis was performed by ROC curve. Cell proliferation, invasion and migration were analyzed by cell proliferation and Transwell assays. Gene interactions were analyzed using luciferase reporter assay. In the present study, it was observed that the expression levels of microRNA­338­3p (miR­338­3p) were reduced in patient lymphoma tissues and a T­LBL cell line. Upregulation of its expression inhibited the migration and proliferation of cultured T­LBL cells. Bioinformatics analysis of putative target mRNAs of miR­338­3p identified a direct binding site in the 3'­untranslated of homeobox A3 (HOXA3). The levels of HOXA3 mRNA and protein were associated with those of miR­338­3p, and overexpression of HOXA3 promoted the malignant phenotype of T­LBL cells. The results suggested that miR­338­3p may suppress the development of T­LBL via the downregulation of oncogenic factors, such as HOXA3. The findings indicated that further investigation into miR­338­3p and the HOXA3 regulatory network may aid the development of novel therapeutic tools.

Inhibition of PLA2G4A Reduces the Expression of Lung Cancer-Related Cytokines.

Phospholipase A2-IVA (PLA2G4A) is the most abundant subtype of cytoplasmic phospholipase A2 (cPLA2) and is an important enzyme in tumor development. Our study aimed to explore the role of PLA2G4A in the regulation of lung cancer. The contents of cell-related cytokines (microsomal prostaglandin E synthase-1 [mPGES], PGE2, and prostacyclin [PGI2]) in A549 cells were analyzed by ELISA kits. Cell counting kit-8 (CCK8) was used to detect the effects of inhibitor of cPLA2 (arachidonyl trifluoromethyl ketone [AACOCF3]) on the proliferation of A549 cells. The migration and invasion of A549 cells were tested by cell scratch wound healing assay and transwell assay, respectively. Real-time quantitative PCR and Western blotting were used to detect the effect of inhibitor AACOCF3 on the expression of related mRNA and protein in A549 cells. ELISA result showed that the levels of mPGES, PGE2, and PGI2 in control group were significantly higher than those in the AACOCF3 group. Cell inhibition rate in the control group was significantly lower than that in the AACOCF3 group. The percentage of wound healing in the control group was significantly higher than that in the AACOCF3 group. Meanwhile, the relative invasive number of cells in the control group was significantly higher than those in the AACOCF3 group. The expression levels of related mRNA of PLA2G4A and cyclooxygenase-2 (COX-2) and the expression levels of mPGES, COX-1, and COX-2 protein in the control group were significantly higher than those in the AACOCF3 group. Our research showed that PLA2G4A was involved in migration and invasion of lung cancer cells.

miR-218 inhibits acute promyelocytic leukemia cell growth by targeting BMI-1.

Acute promyelocytic leukemia (APL) is a subtype of acute myelocytic leukemia. Previous studies have reported a number of functions and therapeutic roles of microRNAs (miRs) in APL, and have suggested that miR-218 acts as a tumor suppressor in a number of types of human cancer; however, its role in APL remains unclear. In the present study, the expression of miR-218 and its effects on the viability and proliferation of HL-60 cells was investigated. Reverse transcription-quantitative polymerase chain reaction analysis demonstrated that miR-218 was frequently downregulated in APL marrow tissues compared with normal marrow tissues. Overexpression of miR-218 significantly inhibited cell proliferation, arrested the cell cycle in the G0/G1 phase and induced apoptosis. In addition, B-cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) mRNA expression was negatively associated with miR-218 expression; BMI-1 mRNA and protein expression were downregulated following transfection with miR-218 mimic. These results indicate that miR-218 functions as tumor suppressor in APL, and the miR-218/BMI-1 signaling axis may be a potential novel diagnostic marker and therapeutic target for the treatment of APL.

Upregulation of miR-125b is associated with poor prognosis and trastuzumab resistance in HER2-positive gastric cancer.

Gastric cancer is one of the most common types of human cancer associated with a poor prognosis. MicroRNAs (miRs), a class of non-coding RNAs that are 18-25 nucleotides in length, act as key regulators in gene expression, and have been implicated in various human cancer types. miR-125b has been implicated in the malignant progression of gastric cancer. However, the association between miR-125b expression, clinicopathological characteristics and trastuzumab resistance in human epidermal growth factor receptor 2 (HER2)-positive gastric cancer remains unclear. In the current study, in situ hybridization data demonstrated that 81.8% (108/132) of gastric cancer tissues exhibited positive expression of miR-125b, while only 26.3% (10/38) of non-tumor gastric tissues were miR-125b-positive. Reverse transcription-quantitative polymerase chain reaction data indicated that the expression level of miR-125b was markedly increased in gastric cancer tissues compared with non-cancerous gastric tissues. Furthermore, the miR-125b level was significantly associated with tumor (T) stage, lymph node metastasis, distant metastasis and TNM stage of gastric cancer (P<0.05). Increased miR-125b expression predicated poor prognosis in patients with gastric cancer. For HER2-positive gastric cancer, the upregulation of miR-125b expression was significantly associated with advanced malignant progression, as well as a poor prognosis (P<0.05). Furthermore, data from the present study indicated that the increased miR-125b level was significantly associated with trastuzumab resistance in HER2-positive gastric cancer (P<0.05). Therefore, the current study suggests that miR-125b may become a potential biomarker for predicting prognoses and clinical outcomes in patients with HER2-positive gastric cancer that receive trastuzumab treatment.

MicroRNA-200c inhibits the metastasis of non-small cell lung cancer cells by targeting ZEB2, an epithelial-mesenchymal transition regulator.

MicroRNAs (miRs) have been demonstrated to regulate various biological processes in human cancer, including non-small cell lung cancer (NSCLC). However, little evidence has been provided regarding the exact role of miR-200c in mediating the malignant progression of NSCLC, as well as the underlying mechanism. The present study aimed to investigate the putative role of miR­200c in the progression of NSCLC. The expression levels of miR­200c were significantly reduced in NSCLC cell lines compared with in normal lung epithelial cells, as determined by reverse transcription­quantitative polymerase chain reaction. Overexpression of miR­200c significantly suppressed cell migration and invasion of A549 NSCLC cells. Results of a luciferase reporter assay further identified zinc finger E­box­binding homeobox 2 (ZEB2) as a direct target gene of miR­200c, and the expression of ZEB2 was shown to be suppressed in A549 cells overexpressing miR­200c. Furthermore, small interfering RNA­mediated inhibition of ZEB2 suppressed the migration and invasion of A549 cells. In addition, since ZEB2 is an epithelial­mesenchymal transition (EMT) regulator, the role of miR­200c in the regulation of EMT in NSCLC cells was further examined. Results of a western blot analysis indicated that overexpression of miR­200c upregulated E­cadherin, and downregulated N­cadherin and vimentin expression in A549 cells, thus suggesting that EMT was suppressed. Based on these results, the present study suggested that miR­200c was able to inhibit the metastasis of NSCLC cells by targeting ZEB2. Therefore, miR-200c may be considered as a potential candidate for the treatment of NSCLC.

Nitidine chloride inhibits proliferation and induces apoptosis in colorectal cancer cells by suppressing the ERK signaling pathway.

Nitidine chloride (NC) is a natural bioactive phytochemical alkaloid that has displayed anticancer activity in various types of cancer. However, no evidence has been reported for the direct effect of NC on CRC cell proliferation and apoptosis, and the underling mechanisms to be fully elucidated. The present study aimed to investigate the influence of NC on the apoptosis and proliferation of CRC cells. The viability and proliferation of CRC cells was measured by MTT assay and a [3H] thymidine uptake assay. Apoptosis was measured using a flow cytometric apoptosis assay and TUNEL staining. The expression levels of apoptotic­regulated proteins in addition to extracellular signal­regulated kinase (ERK) were measured by western blot analysis following stimulation with NC. The results indicated that NC inhibited the proliferation of HCT116 cells in a dose­ and time­dependent manner. Additionally, apoptotic induction by NC treatment was confirmed. Furthermore, NC was demonstrated to significantly upregulate the expression of Bax, p53, cleaved caspase­3 and ­9 and downregulate the expression of Bcl­2. Treatment with NC reduced the phosphorylation of ERK and by using an ERK inhibitor, U0126, the roles of NC in apoptotic induction and the inhibition of proliferation were further demonstrated. These results demonstrated that NC inhibited the proliferation and induced the apoptosis of CRC cells via the ERK signaling pathway.