[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.

Analysis of Approaches in the Microsurgical Treatment of 102 Cases of Petroclival Meningioma in a Single Center.

Objectives: We identified the optimal approaches for treating the diverse tumor subtypes of petroclival meningioma (PM) by analyzing the clinical benefits of various surgical approaches adopted for each subtype. Methods: Tumors in 102 PM patients from a single center who underwent surgical treatment were classified as upper clivus (UC), cavernous sinus (CS), tentorium (TE), or petrous apex (PA) types based on the attachment site of the tumor base and the displacement of the trigeminal nerve. The therapeutic effects of different surgical approaches among the subtypes were evaluated according to the patient outcomes. Results: The subtemporal (33.33%), retrosigmoid (16.67%), and Kawase approaches (50%) were used for the UC type. Simpson I/II resection was achieved in 46.66% of patients with the Kawase approach. Significant differences were found between the other two approaches (P = 0.044) and in the follow-up Karnofsky performance scale (KPS) scores (P = 0.008). The subtemporal (60%) and Kawase approaches (40%) were used for the CS type; neither approach achieved Simpson I/II resection. The retrosigmoid (25.81%) and Kawase approaches (74.19%) were used for the TE type. The Simpson I/II resection rates of the two approaches were 55.55 and 86.95%, respectively, and a significant difference was observed between them (P = 0.039). The retrosigmoid (43.75%) and Kawase approaches (56.25%) were used for the PA type. The Simpson I/II resection rates of the two approaches were 31.25 and 50%, respectively. The resection degrees of the two approaches and the KPS scores at follow-up were significantly different (P = 0.034). Conclusion: The individual microsurgical approaches adopted for the various PM tumor subtypes can provide maximal safe resection and good KPS scores. The Kawase approach is more suitable for PM, especially for UC- and PA-type PM tumors.