[Inhibition of GMA-induced ubiquitination process in 16HBE malignantly transformed cells on protein CD44 and MMP14].

OBJECTIVE: To observe the effect of the ubiquitination process on the expression of CD44 antigen(CD44) and matrix metalloproteinase-14(MMP14) in human bronchial epithelial(16HBE) malignantly transformed cells induced by glycidyl methacrylate(GMA). METHODS: Successfully resuscitated 16HBE cells were cultured using a final concentration of 8 µg/mL GMA as the treatment group and 1 µg/mL dimethyl sulfoxide as the solvent control group, each time stained for 72 h, and then stained again after an interval of 24 h. After repeating the staining three times, the cells were cultured in passages respectively. The 40th generation(P40) GMA-treated group and the same-generation solvent control group were subjected to soft agar colony formation assay and concanavalin A(ConA) agglutination test to confirm that the 40th generation of GMA-induced malignant transformed 16HBE cells possessed malignant transformed cell characteristics.5, 10, 20, 40, 60 µmol/L anacardic acid were used to inhibit the ubiquitination process of GMA-induced malignant transformed 16HBE cells. The protein expression of CD44 and MMP14 were detected by western blotting, while the transcript levels of CD44, MMP14, and TFAP2A were assessed by real-time fluorescence quantitative PCR(qPCR). RESULTS: (1) In the soft agar colony formation assay, the number of clones formed by the cells in the solvent control group was 22, and the number of clones created by the malignantly transformed cells in the GMA-treated group was 208. In the ConA agglutination test, the cells in the solvent control group were uniformly dispersed in ConA solution, and no obvious agglutination occurred for 30 min, whereas the cells in the GMA-treated group were agglutinated in the 5th min, and the agglutinated cells were larger and more rapidly agglutinated. The agglomerates were more significant and faster, and the sensitivity of agglutination was increased. (2) After differential inhibition of GMA-induced ubiquitination in malignantly transformed 16HBE cells, the expression levels of CD44 and MMP14 were reduced in GMA-induced malignantly transformed 16HBE cells compared with the control group(P<0.05). The transcript levels of MMP14 and CD44 decreased with increasing inhibitor concentration(P<0.05), and the transcript levels of the upstream transcription factor TFAP2A were also simultaneously reduced(P<0.05). CONCLUSION: Inhibition of the cellular ubiquitination process mediates the down-regulation of protein expression and transcriptional expression of CD44 and MMP14 in GMA-induced malignantly transformed 16HBE cells.

TMT-based quantitative proteomic analysis reveals the underlying mechanisms of glycidyl methacrylate-induced 16HBE cell malignant transformation.

Glycidyl methacrylate (GMA) has been widely used as tackifying/crosslinking copolymer monomer in the industrial section. Occupational and environmental exposure to GMA is inevitable. GMA is classified as a Group 2 A carcinogen. However, it still lacks a sufficient understanding of its carcinogenicity at the protein level. The major pathways and players during the malignant transformation process remain unknown. In this study, we first established and characterized a malignant transformation model using human bronchial epithelial (16HBE) cells exposed to 8 µg/mL GMA. Then the proteomics approach, western-blot analysis as well as quantitative PCR (qPCR) analysis were employed to investigate its underlying mechanisms of carcinogenicity. Our results showed that the 16HBE cells exposed to GMA and passaged to the 40th generation had undergone a malignant transformation. Proteomic analysis revealed that 123 proteins were significantly up-regulated while 160 proteins were down-regulated during the process of malignant transformation. Importantly, further pathway analysis identified the extracellular matrix-receptor (ECM-receptor) interaction pathway to be one of the major players mediating the process and most of the differentially expressed proteins (DEPs) were up-regulated, including two vital proteins, CD44 and MMP14, as well as members from integrin family. These results provide direct proteomic evidence that DEPs related to the ECM-receptor interaction pathway play an active role in reinforcing the carcinogenicity of GMA. The findings of this study might deepen our understanding of the underlying mechanisms of GMA carcinogenicity and thus facilitate the risk assessment of GMA.

Biomarkers of exposure and effect in the serum and urine of rats or workers exposed to 1-bromopropane.

Extensively used in several industries in China as a cleaning agent, 1-bromopropane (1-BP) has significant adverse effects on the central nervous system. However, neither its mechanism of action nor sensitive biomarkers related to it have been determined thus far. In this study, animal experiments and occupational surveys were performed to explore the typical exposure and effect biomarkers of neurotoxicity induced by 1-BP. Male Wistar rats were exposed to 0, 500, or 1000 ppm of 1-BP followed by pathological and biomarker analyses. An epidemiological survey was conducted on 71 workers each from 1-BP exposed and control groups. Serum and urine samples were collected for biomarker testing. cNSE represents neuron-specific enolase (NSE) in the cerebral cortex, where as sNSE represents NSE in the serum; similar terminology applies to S-100ß, and cyclooxygenase-2 (COX-2). In rats exposed to 1000 ppm 1-BP, pathological changes were observed in Purkinje cells, lumbar gray matter, and tibiofibular nerve, while levels of cNSE, cS-100ß, cCOX-2, sS-100ß, and sCOX-2 were significantly elevated at different time checkpoints. In the 500 ppm group, cCOX-2, sNSE, and sCOX-2 levels were significantly elevated at different time checkpoints. 1-BP and N-acetyl-S-(n-propyl)-L-cysteine (AcPrCys) were detected in rat urine, and there was a correlation between the level of sNSE or sCOX-2 and AcPrCys in the 500 ppm group. In the occupational epidemiological study, a significant correlation between AcPrCys and exposure concentration was also detected. The findings of this study indicated that AcPrCys was a sensitive exposure biomarker of 1-BP in rats as well as occupational populations.

[Role of LncRNA CASC11 in the malignant transformation of 16HBE cells induced by glycidyl methacrylate].

OBJECTIVE: To investigate the effect of trending up-regulation LncRNA CASC11 which is differentially expressed during the malignant transformation of human bronchial epithelial cells(16 HBE) induced by glycidyl methacrylate(GMA). METHODS: After 16 HBE cells were repeatedly exposed to low concentration GMA(8 µg/mL), the 10 th, 20 th and 30 th passage cells of the GMA group and the DMSO solvent control group were collected. High throughput LncRNA microarray were used to screen the differentially expressed LncRNAs at different stages. Short Time-series Expression Miner and bioinformatics tool RPISeq were used to screen and predict the potential targets of specific LncRNA. Real-time fluorescent quantitative PCR(qPCR) and Western blot were used to detect the relative expression of specific LncRNA and the content of its target protein respectively. RESULTS: The specific differential expression of LncRNA CASC11 in the process of GMA-induced malignant transformation of 16 HBE cells showed a trend of up-regulation. Compared with the control cells in the same period, the P10, P20 and P30 generation cells were down-regulated by 1.64 times, up-regulated by 2.01 times, and up-regulated by 2.66 times, respectively. Western blot showed that the levels of cyclin-dependent kinase 1(CDK1), cyclinB1 and cyclinB2 in P10, P20 and P30 cells after exposure were lower than those in DMSO control group during the same period, which was consistent with the microarray results. CONCLUSION: The differential expression of LncRNA CASC11 in the process of GMA-induced 16 HBE cell malignant transformation was up-regulated trendingly. It is speculated that it may block or delay cell cycle progression by inhibiting CDK1.

[Role of LINC00310 in the glycidyl methacrylate-induced malignant transformation of human bronchial epithelial cell].

OBJECTIVE: To investigate the expression and biological significance of LINC00310 in the malignant transformation of human bronchial epithelial cells(16 HBE) induced by glycidyl methacrylate(GMA). METHODS: The 16 HBE cells recovered successfully used 1 µg/mL dimethyl sulfoxide(DMSO) as the solvent control group, and the final concentration was 8 µg/mL GMA as the treatment group, and were subcultured after repeated exposure 3 times for 72 hours each time. The 10 th, 20 th and 30 th generation cells of the GMA treatment group and corresponding DMSO control group were collected. The LncRNA microarrays was used to analyze the expression changes of LINC00310 in different periods, and the target gene and function prediction was performed by NCBI and cBioPortal bioinformatics database, and real-time quantification PCR(qPCR) was used to detect the relative expression levels of LINC00310 and predicted target genes. RESULTS: The result of the microarray showed that LINC00310 in the GMA-treated group was down-regulated by 2. 02-fold, up-regulated by 6. 17-fold, and up-regulated by 2. 03-fold in the pre-transformation, mid-term, and late, respectively. The result of qPCR confirmed that the expression of LINC00310 relative expression level of 10 th, 20 th and 30 th generation cells was consistent with the microarray result, which were down-regulated by 2. 76-fold, up-regulated by 2. 68-fold, and up-regulated by 3. 09-fold. Consistently, the relative expression of the target gene C-Myc was statistically significant in 20 th and 30 th generation cells. CONCLUSION: LINC00310 induced low expression in the early stage of malignant transformation of 16 HBE cells induced by GMA, and was highly expressed in the middle and late stages. It indicated that LINC00310 may play a cancer-promoting role in the process of cell malignant transformation through C-Myc.