Loss of CPAP causes sustained EGFR signaling and epithelial-mesenchymal transition in oral cancer

Overexpression of RAB27A in Oral Squamous Cell Carcinoma Promotes Tumor Migration and Invasion via Modulation of EGFR Membrane Stability

Oral squamous cell carcinoma (OSCC) is the most prevalent subtype of head and neck tumors, highly prone to lymph node metastasis. This study aims to examine the expression pattern of Ras-related protein Rab-27A (RAB27A) and explore its potential implications in OSCC. The expression of RAB27A was assessed through immunohistochemical analysis utilizing tissue microarrays. In vitro experiments were conducted using RAB27A-knockdown cells to investigate its impact on OSCC tumor cells. Additionally, transcriptome sequencing was performed to elucidate potential underlying mechanisms. RAB27A was significantly overexpressed in OSCC, and particularly in metastatic lymph nodes. It was positively correlated with the clinical progression and poor survival prognosis. Silencing RAB27A notably decreased the proliferation, migration, and invasion abilities of OSCC cells in vitro. A Gene Ontology (GO) enrichment analysis indicated a strong association between RAB27A and the epidermal growth factor receptor (EGFR) signaling pathway. Further investigations revealed that RAB27A regulated the palmitoylation of EGFR via zinc finger DHHC-type containing 13 (ZDHHC13). These findings provide insights into OSCC progression and highlight RAB27A as a potential therapeutic target for combating this aggressive cancer.

miR-146 Relieves Acute Asthma via Decreasing Epidermal Growth Factor Receptor/Toll-Like Receptor 4 (EGFR/TLR4) and Enhancing Autophagy

There is a close relationship between acute asthma and autophagy. In addition, some studies claim that miR-146 can regulate autophagy and participate in acute asthma. This study further explores the role of miR-146 in acute asthma and underlying mechanism. Twenty BALB/c mice were selected and randomly divided into two groups, the model group and the control group, each with 10 mice. Lung tissues, peripheral blood, alveolar lavage fluid, and primary lymphocytes were separated into miR-146 over expression group (miR-146 mimic), miR-146 low expression group (miR-146 inhibitor), negative control group (NC), blank group, or SBI-0206965 group. Acute asthma was established and the expression levels of miR-146, EGFR, TLR4, LC3, beclin1, and ATG5 in each group was measured. The targeting relationship and correlation between miR-146 and EGFR were also investigated. The expression of IL-4 in model group was increased compared to control arm while the expression of IFN-γ was opposite (P < 0.05). The expressions of miR-146, LC3, beclin1, and the expression of ATG5 were decreased (P < 0.05). The expressions of miR-146 gene and LC3, beclin1, ATG5 mRNA and protein in the miR-146 mimic group were the highest, while the expressions of EGFR and TLR4 were the lowest. The SBI-0206965 group and the miR-146 inhibitor group are opposite to the miR-146 mimic group, the SBI-0206965 group and the miR-146 inhibitor group have significant differences (P < 0.05). miR-146 has a directly targeted EGFR and TLR4, and both showed a negative correlation (rEGFR=−0.397, P = 0.013; rTLR4=−0.402, P = 0.021). During the onset of asthma, miR-146 was abnormally decreased. miR-146 directly targets and negatively regulates EGFR. In addition, miR-146 down-regulates TLR4 gene to increase CD4+ lymphocytes’ aphagocytosis-related markers (LC3, beclin1, ATG5) which further promotes the autophagy process and ultimately alleviates the degree of acute asthma. Its main mechanism is related to the down-regulation of the EGFR/TLR4 through regulated the expression of autophagy. Our study provided a scientific reference for further understanding of acute pathogenesis of asthma.

TAB2 Promotes the Biological Functions of Head and Neck Squamous Cell Carcinoma Cells via EMT and PI3K Pathway

Background

Transforming growth factor β₁-activated kinase 1 binding protein 2 (TAB2) mediates a variety of biological processes through activated nuclear factor κ-light-chain-enhancer of activated B cell (NF-κB) signaling pathways. TAB2 has been reported to be upregulated in a variety of tumors. However, little is known about its potential role in oral squamous cell carcinoma (OSCC). Material and Methods. Patients' clinicopathological and transcription data were obtained from The Cancer Genome Atlas (TCGA) database. Immunohistochemistry staining was used to determine TAB2 expression in OSCC tissues (IHC). The expression of TAB2 in OSCC cell lines was detected by western blotting. The CCK-8 test and flow cytometry assay were utilized to evaluate cell proliferation, apoptosis, and cell cycle in OSCC cell lines. Enrichment analysis and identification of predicted signaling pathways were performed by Gene Ontology and KEGG analysis. Finally, the expression of downstream signal molecules was performed using western blotting to validate the mechanism investigations.

Results

TAB2 expression level was aberrantly upregulated in OSCC patients. TAB2 expression was shown to be inversely associated to prognosis. The phenotypic of OSCC cells was considerably impacted by TAB2. OSCC cells with deleted TAB2 exhibit decreased proliferation and increased apoptosis. Additionally, OSCC progression is aided by TAB2 overexpression. Further mechanism studies showed that TAB2 could regulate the progression of OSCC by mediating the upregulation of EMT and PI3K-AKT signaling pathways.

Conclusion

This study sheds light on the carcinogenic role of TAB2 in OSCC and provides a potential therapeutic strategy.

Altered protein profile of plasma extracellular vesicles in oral squamous cell carcinoma development

Extracellular vesicles (EVs) are involved in a wide range of pathological processes and recognized as potential and novel biomarkers for oral squamous cell carcinoma (OSCC). Here, we describe the plasma EV proteome of rats with 4-nitroquinoline-1-oxide (4NQO)-induced OSCC or moderate dysplasia (MD), which can progress to OSCC, by tandem mass tag (TMT)-labeled mass spectrometry. The proteomic profiles suggest the differential expression of various proteins in MD and OSCC, some well-recognized pathological changes (e.g., translation, ATP metabolism, and mesenchymal transition), and some novel pathological changes (e.g., podosome, focal adhesion, and S100 binding). We re-examined the presence of traditional exosomal markers and the reported novel pan-EV markers. In summary, these results suggest potential EV biomarkers and underlying pathological changes in early OSCC as well as the presence of oral-derived EVs in plasma and the need for pan-EV markers. SIGNIFICANCE: This research suggests potential EV biomarkers and underlying pathological changes in early OSCC as well as the presence of oral-derived EVs in plasma and the need for pan-EV markers.