Tongue Cancer Cell Line Research Articles

Exploring the Biological Potential of Mountain Germander Polyphenolic Extract on Cellular Model Macromolecules, Human Cell Lines, and Microbiome Representatives

In the context of revitalizing the use of traditional plant species as remarkable sources of bioactive compounds, the determination of their biological effects is of utmost importance. Among Lamiaceae species, Teucrium montanum (Mountain Germander) represents understudied Mediterranean plant species; it is rich in polyphenols, which are well-studied biologically active compounds for human disease prevention and the reduction of oxidative stress, i.e., phenolic acids, phenylethanoid glycosides, and flavonoids. For that purpose, the aim of this study was to investigate the antioxidant, cytotoxic, and genotoxic effects of Mountain Germander (MG) polyphenolic extract (0.025, 0.050, 0.150, and 0.500 mg extract mL−1) on the hepatocellular (HepG2), tongue (CAL 27), gastric (AGS), and colorectal (Caco-2) continuous human cancer cell lines, as well as its bacteriostatic potential on representative members of human microbiota. In addition, the antioxidant potential of the MG polyphenolic extract was determined using bovine serum album and DNA plasmid as cellular model macromolecules. In vitro analysis revealed a significant cytotoxic effect of all MG extract concentrations on AGS and Caco-2 cell lines after prolonged treatment (24 h). In addition, treatment with 0.500 mg extract mL−1 showed the most pronounced antioxidant effect under prolonged treatment (24 h) on CAL 27 and HepG2 cell lines. All of the applied MG extract concentrations seem to have a genoprotective effect on DNA plasmid. Furthermore, a significant inhibitory effect on E. coli was detected upon the treatment with 0.150 mg extract mL−1, reducing the cell viability by 56%.

Synthesis of epoxyazadiradione-thiazole hybrid derivatives and evaluation of their cytotoxic activities

In an attempt to develop natural product-based anticancer agents, a series of novel epoxyazadiradione-thiazole hybrids (6a-j) were synthesised and evaluated for their anticancer activity. All the synthesised derivatives were assessed for in vitro cytotoxic activity against a panel of human cancer and normal cell lines and the results showed that most of the compounds exhibited significant cytotoxic activity against cancer cells and as well some of the compounds showed less cytotoxicity against normal cells. In particular, compound 4 showed potent cytotoxic activity against tongue cancer cell lines. In consideration of the potent activity, the compound 4 was further assessed for cell cycle analysis and the results showed that the compound arrests the cell cycle progression at the G0/G1 phase in the tongue cancer cell lines. Consequently, the annexin V/PI staining assay demonstrated that compound 4 induced early apoptosis against tongue cancer. Taken together, the results inferred that the epoxyazadiradione is promising anticancer candidate for developing novel anticancer drugs against tongue cancer.

Enhanced targeted liposomal delivery of imiquimod via aptamer functionalization for head and neck cancer therapy

The incidence of head and neck cancers, particularly those associated with Human Papillomavirus (HPV) infections, has been steadily increasing. Conventional therapies exhibit limitations and drawbacks, prompting the exploration of new strategies over the years, with nanomedicine approaches, especially liposomes gaining relevance. Additionally, the functionalization of liposomes with aptamers enables selective delivery to target cells. For instance, AT11 can serve as a targeting moiety for cancer cells due to its high affinity for nucleolin, a protein overexpressed on the cancer cell’s surface. In this study, liposomes functionalized with AT11 are proposed as drug delivery systems for imiquimod (IQ), aiming to maximize its potential as an anticancer agent for HPV-related cancers.To this end, firstly liposomes were produced through the ethanol injection method, functionalized with AT11-TEG-Cholesteryl, and characterized using dynamic light scattering. The obtained liposomes presented suitable properties for cancer therapy (with sizes from 120 to 140 nm and low polydispersity PDI < 0.16) and were further evaluated in terms of potential anticancer effects. AT11 IQ-associated liposomes allowed a selective delivery of IQ towards a tongue cancer cell line (UPCI-SCC-154) relative to the non-malignant cell line (Het1A). Specifically, they induced a selective reduction of the cell viability (∼52 % versus ∼113 %; p < 0.0001), proliferation (∼68 % versus ∼102 %; p<0.0001) and increased cell death (∼7-fold increase; p < 0.0001)). Additionally, they decreased the migration (from ∼24 % to ∼8 %; p < 0.0001) and invasion (to 11 %; p = 0.0047) capacities of the cancer cells.In summary, the produced liposomes represent a promising approach to enhance the anticancer potential of IQ in head and neck cancer, particularly in tongue cancer.

Global analysis of DNA methylation changes during experimented lingual carcinogenesis.

This study aims to assess the role of DNA methylation changes in tongue cancer through a comprehensive analysis of global DNA methylation alterations during experimental lingual carcinogenesis. C57BL/6J mice were subjected to 16-week oral administration of 4-nitroquinoline-1-oxide (4NQO, 50 mg/L). Lingual mucosa samples, being representative of normal tissue (week 0) and early (week 12) and advanced (week 28) tumorigenesis, were harvested for microarray and methylated DNA immunoprecipitation sequencing (MeDIP-Seq). The mRNA and promoter methylation of transforming growth factor-beta-signaling protein 1 (SMAD1) were evaluated with real-time quantitative reverse transcription polymerase chain reaction and Massarray in human lingual mucosa and tongue cancer cell lines. The cytosine guanine island (CGI) methylation level observed at 28 weeks surpassed that of both 12 weeks and 0 weeks. The promoter methylation level at 12 weeks exceeded that at 0 weeks. Notably, 208 differentially expressed genes were negatively correlated to differential methylation in promoters among 0, 12, and 28 weeks. The mRNA of SMAD1 was upregulated, concurrent with a decrease in promoter methylation levels in cell lines compared to normal mucosa. DNA methylation changed during lingual carcinogenesis. Overexpression of SMAD1 was correlated to promoter hypomethylation in tongue cancer cell lines.

Prognostic significance of the FSTL1-DIP2A axis in early-stage tongue cancer.

In tongue cancer, many patients already have metastasis at the time of diagnosis, and such cases are usually unresponsive to treatment, resulting in a poor prognosis. Therefore, there is an urgent need to develop more effective diagnostic and therapeutic methods to cure tongue cancer at the earliest possible stage in clinical practice. Follistatin-like 1 (FSTL1) is known as a negative effector molecule that induces and enhances the refractoriness of cancer cells directly and indirectly via suppressing anti-tumor immunity in various types of cancer. However, the molecular expression, functions, and clinical significance of FSTL1 and its receptor DIP2A in tongue cancer remains to be elucidated. In this study, we revealed that FSTL1, which is highly expressed in tongue cancer cells, plays a key role in its malignancy and is a significant risk factor for recurrence of early-stage tongue cancer. Basic study shows that FSTL1 is abundantly produced from human tongue cancer cell lines, and blocking FSTL1 with specific siRNAs or mAb significantly suppresses cellular functions. Clinical study shows that both FSTL1 and its receptor DIP2A are highly and correlatively expressed in tumor tissues of tongue cancer patients, and high expression levels of both in stage I tumors are significantly associated with shorter relapse-free survival. These suggest that targeting the FSTL1-DIP2A axis may be useful as a biomarker for early prediction of prognosis in tongue cancer patients, and as a therapeutic target for developing new drugs to treat tongue cancer more effectively. This strategy will contribute to improving clinical outcomes in tongue cancer.

Studying the Functional Potential of Ground Ivy (Glechoma hederacea L.) Extract Using an In Vitro Methodology

Glechoma hederacea L., known as ground ivy, has a long history of use in folk medicine. The main bioactive compounds in ground ivy are polyphenolic compounds known for their potent antioxidant and antimicrobial activities and thus have high potential as functional ingredients against bacterial infections and the occurrence of chronic diseases associated with oxidative stress in the human body. The aim of the present study was to determine the biological activity of ground ivy extract on selected human cell lines, including hepatic (HepG2), tongue (CAL 27), gastric (AGS) and colon (Caco-2) cancer cell lines by evaluating cytotoxicity, formation of reactive oxygen species and genotoxicity. The antioxidant capacity of the extract was additionally evaluated using cellular model macromolecules of protein and DNA, bovine serum album and plasmid phiX174 RF1 DNA. The effect of ground ivy extract on representatives of human microflora, including L. plantarum, E. coli and S. aureus, was also studied. The cytotoxicity of the extract depended on the type of cells treated, and the pro-oxidant effect generally decreased with increasing exposure time. The most pronounced genoprotective effect against hydroxyl radical damage was monitored in model plasmid DNA and occurred at the highest tested concentration (0.25 mg mL−1), with 95.89% preservation of the supercoiled form of the plasmid. This concentration also had the most significant antioxidant activity on the model protein—14.01% more than the positive control prepared using Trolox. The ground ivy extract showed high antimicrobial potential against the pathogenic bacteria E. coli and S. aureus.

Polypodium leucotomos targets multiple aspects of oral carcinogenesis and it is a potential antitumor phytotherapy against tongue cancer growth.

Introduction: Oral cancer refers to malignant tumors, of which 90% are squamous cell carcinomas (OSCCs). These malignancies exhibit rapid progression, poor prognosis, and often mutilating therapeutical approaches. The determination of a prophylactic and/or therapeutic antitumor role of the polyphenolic extract Polypodium leucotomos(PL) would be relevant in developing new tools for prevention and treatment. Methods: We aimed to determine the antitumor effect of PL by treating OSCC cell lines with PL metabolites and evaluating its action during OSCC progression in vivo. Results: PL treatment successfully impaired cell cycling and proliferation, migration, and invasion, enhanced apoptosis, and modulated macrophage polarization associated with the tumoral immune-inflammatory response of tongue cancer cell lines (TSCC). PL treatment significantly decreased the expression of MMP1 (p < 0.01) and MMP2 (p < 0.001), and increased the expression of TIMP1 (p < 0.001) and TIMP2 (p < 0.0001) in these cells. The mesenchymal-epithelial transition phenotype was promoted in cells treated with PL, through upregulation of E-CAD (p < 0.001) and reduction of N-CAD (p < 0.05). PL restrained OSCC progression in vivo by inhibiting tumor volume growth and decreasing the number of severe dysplasia lesions and squamous cell carcinomas. Ki-67 was significantly higher expressed in tongue tissues of animals not treated with PL(p < 0.05), and a notable reduction in Bcl2 (p < 0.05) and Pcna (p < 0.05) cell proliferation-associated genes was found in dysplastic lesions and TSCCs of PL-treated mice. Finally, N-cad(Cdh2), Vim, and Twist were significantly reduced in tongue tissues treated with PL. Conclusion: PL significantly decreased OSCC carcinogenic processes in vitro and inhibited tumor progression in vivo. PL also appears to contribute to the modulation of immune-inflammatory oral tumor-associated responses. Taken together, these results suggest that PL plays an important antitumor role in processes associated with oral carcinogenesis and may be a potential phytotherapeutic target for the prevention and/or adjuvant treatment of TSCCs.

Effect of Ablative Dose Irradiation on Redistribution and Radioresponse in a Mouse Xenograft Model.

We investigated the effects of ablative dose irradiation on redistribution and radioresponse after the second irradiation in a mouse xenograft model, assuming stereotactic body radiotherapy (SBRT). A human tongue cancer cell line, SAS-Fucci, expressing the fluorescent ubiquitination-based cell cycle indicator (Fucci) that visualizes the cell cycle, was employed in this study. Tumor xenografts formed subcutaneously in nude mice (approximately 6 mm in diameter), with essentially no hypoxic regions, were irradiated at 10 Gy and G2 arrest kinetics were determined using histology sections and a real-time detection method. The second irradiation (10 Gy) was given at intervals of 0 h, 3 h, 1 day, and 4 days after the first irradiation, and tumor regrowth curves were obtained. It was revealed that the ratio of G2-arrested cells showed a much higher peak at 1 day postirradiation compared to 2 Gy, assuming conventional radiotherapy, and gradually decreased thereafter up to 4 days. Tumors irradiated at intervals of 0 h and 1 day demonstrated significantly higher radioresponses than other timings. We conclude that redistribution could contribute to the efficacy of SBRT.

Oral Cancer Cells Release Vesicles that Cause Pain.

Oral cancer pain is attributed to the release from cancers of mediators that sensitize and activate sensory neurons. Intraplantar injection of conditioned media (CM) from human tongue cancer cell line HSC-3 or OSC-20 evokes nociceptive behavior. By contrast, CM from noncancer cell lines, DOK, and HaCaT are non-nociceptive. Pain mediators are carried by extracellular vesicles (EVs) released from cancer cells. Depletion of EVs from cancer cell line CM reverses mechanical allodynia and thermal hyperalgesia. CM from non-nociceptive cell lines become nociceptive when reconstituted with HSC-3 EVs. Two miRNAs (hsa-miR-21-5p and hsa-miR-221-3p) are identified that are present in increased abundance in EVs from HSC-3 and OSC-20 CM compared to HaCaT CM. The miRNA target genes suggest potential involvement in oral cancer pain of the toll like receptor 7 (TLR7) and 8 (TLR8) pathways, as well as signaling through interleukin 6 cytokine family signal transducer receptor (gp130, encoded by IL6ST) and colony stimulating factor receptor (G-CSFR, encoded by CSF3R), Janus kinase and signal transducer and activator of transcription 3 (JAK/STAT3). These studies confirm the recent discovery of the role of cancer EVs in pain and add to the repertoire of algesic and analgesic cancer pain mediators and pathways that contribute to oral cancer pain.

Deoxyshikonin Mediates Heme Oxygenase-1 Induction and Apoptotic Response via p38 Signaling in Tongue Cancer Cell Lines.

Deoxyshikonin (DSK), a phytochemical constituent, has been documented to elicit various oncostatic properties alone or in combination with established therapeutics. However, its role in restraining oral squamous cell carcinoma (OSCC) is mostly unclear. Here, we examined the tumor-suppressive effect of DSK and explored the molecular mechanisms underlying DSK’s activities on controlling oral cancer. Our results showed that DSK dose-dependently lessened the cell viability of tongue cancer cell lines, involving induction of cell cycle arrest at the sub-G1 phase and apoptotic cell death. Moreover, a unique signature of apoptosis-related proteins, including augmented nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) expression and caspase activation, was observed in DSK-treated tongue cancer cell lines. Furthermore, DSK-mediated upregulation of HO-1 and cleavage of caspase-9 and -3 were significantly inhibited by pharmacological blockage of p38 kinase. Collectively, these data revealed that DSK halted cell cycle progression and elicited cell apoptosis in tongue cancer cell lines, reshaping a p38-dependent profile of apoptotic proteome. Our findings provided novel insights into the therapeutic implications of a natural compound on the management of OSCC.

The Wnt Signaling Pathway Inhibitors Improve the Therapeutic Activity of Glycolysis Modulators against Tongue Cancer Cells.

Excessive glucose metabolism and disruptions in Wnt signaling are important molecular changes present in oral cancer cells. The aim of this study was to evaluate the effects of the combinatorial use of glycolysis and Wnt signaling inhibitors on viability, cytotoxicity, apoptosis induction, cell cycle distribution and the glycolytic activity of tongue carcinoma cells. CAL 27, SCC-25 and BICR 22 tongue cancer cell lines were used. Cells were treated with inhibitors of glycolysis (2-deoxyglucose and lonidamine) and of Wnt signaling (PRI-724 and IWP-O1). The effects of the compounds on cell viability and cytotoxicity were evaluated with MTS and CellTox Green tests, respectively. Apoptosis was evaluated by MitoPotential Dye staining and cell cycle distribution by staining with propidium iodide, followed by flow cytometric cell analysis. Glucose and lactate concentrations in a culture medium were evaluated luminometrically. Combinations of 2-deoxyglucose and lonidamine with Wnt pathway inhibitors were similarly effective in the impairment of oral cancer cells’ survival. However, the inhibition of the canonical Wnt pathway by PRI-724 was more beneficial, based on the glycolytic activity of the cells. The results point to the therapeutic potential of the combination of low concentrations of glycolytic modulators with Wnt pathway inhibitors in oral cancer cells.

APOPTOSIS MEDIATED ANTI-PROLIFERATIVE ACTIVITY OF KAEMPFEROL AND QUERCETINE ISOLATED FROM THE LEAVES OF ALTINGIA EXCELSA AGAINST HUMAN TONGUE SP-C1 CELL LINES

Introduction: The leaves of Altingia excelsa were found to strongly inhibit SP-C1 human tongue cancer cell lines. This study was focused on identifying antiproliferative compounds found in A. excelsa leaves and assesment their action mechanism. Methods: Extracts of Methanol A. excelsa were fractionated based on their solvent polarity using n-hexane, ethyl acetate, and water. The anti-proliferative testing were tested in vitro against SP-C1 human tongue cancer cell lines using the MTT assay. Isolated the active compound used column chromatography and identified by the spectroscopic method. The isolated compound was also tested for its anti-proliferative testing and ELIZA method of apoptotic induction. Results: This work resulted in the isolation of a flavonoid, which was identified to be kaempferol and quercetin. The compound inhibited SP-C1 proliferation of cell in a time- and dosedependent manner with IC50 values of 0.72 µg/mL and 0. 70 µg/mL for the 24 hours treatments, respectively. Furthermore, promoting apoptosis via the intrinsic pathway, thereby increasing the activity of caspase-8 and caspase-9. Conclusions: These results suggest that kaempferol and quercetin the anticancer compound found in A, excelsa provided a basic for its potential use in cancer disease treatment management

A Study of the Lipidomic Profiles of the CAL-27 and HOK Cell Lines Using EMS Spectra.

ObjectiveThe aim of this study was to explore the lipidomic profiles of the CAL-27 human tongue cancer cell line and the human oral keratinocyte (HOK) cell line.MethodsThe lipidomic differences between the CAL-27 and the HOK cell lines were investigated using non-targeted high-performance liquid chromatography–mass spectrometry lipidomic analysis. The resulting data were then further mined via bioinformatics analysis technology and metabolic pathway analysis was conducted in order to map the most affected metabolites and pathways in the two cell lines.ResultsA total of 711 lipids were identified, including 403 glycerophospholipids (GPs), 147 glycerolipids, and 161 sphingolipids. Comparison of the enhanced MS (EMS) spectra of the two cell lines in positive and negative ionization modes showed the lipid compositions of HOK and CAL-27 cells to be similar. The expressions of most GP species in CAL-27 cells showed an increasing trend as compared with HOK, whereas a significant increase in phosphatidylcholine was observed (p < 0.05). Significant differences in the lipid composition between CAL-27 and HOK cells were shown as a heatmap. Through principal component analysis and orthogonal partial least squares discriminant analysis, noticeably clear separation trends and satisfactory clustering trends between groups of HOK and CAL-27 cells were identified. The numbers of specific lipid metabolites that could distinguish CAL-27 from HOK in positive and negative modes were 100 and 248, respectively. GP metabolism was the most significantly altered lipid metabolic pathway, with 4 metabolites differentially expressed in 39 hit products.ConclusionThis study demonstrated the potential of using untargeted mass spectra and bioinformatics analysis to describe the lipid profiles of HOK and CAL-27 cells.

Kaempferol and Quercetin Isolated from The Leaves of Atingia Excelsa to Arrest Cell Cycle in G0/G1 Phase Human Tongue Cancer SP-C1 Cell Lines

The leaves of Altingia excelsa were found to strongly inhibit SP-C1 human tongue cancer cell lines. This study was focused on identifying the antiproliferative compound found in A. excelsa leaves and assessing its mechanism of action. The active compound was isolated using column chromatography and identified by the spectroscopic method and was also tested for its anti-proliferative properties and the cell cycle analysis in SP-C1 cells by flowcytometry analysis. This work resulted in the isolation of a flavonoid, which was identified to be kaempferol and quercetin. The compounds inhibited SP-C1 cell proliferation in a time- and dose-dependent manner with IC50 values of 0.72 µg/mL and 0. 70 µg/mL for the 24 hours treatments, respectively. Furthermore, the flowcytometry analysis suggested that the compounds exerted its anticancer activities by inhibiting cell cycle. These results suggested that compounds found in A. excelsa providies a basis for its potential use in cancer disease management.&#x0D;

The combinatorial inhibition of Wnt signaling and Akt kinase is beneficial for reducing the survival and glycolytic activity of tongue cancer cells.

Wnt signaling is important in the development of head and neck squamous cell carcinomas (HNSCC); however, Wnt pathway inhibitors lack satisfactory potency when used in monotherapy. The aim of this study was to assess the effects of the combinations of Wnt-signaling inhibitors and the inhibitor of Akt kinase on the survival and glycolytic activity of tongue carcinoma cells. CAL27, SCC-25, and BICR22 tongue cancer cell lines were used. Cells were treated with Wnt signaling (PRI-724 and IWP-O1) and Akt-kinase inhibitors. The effect of the chemicals on cell viability and cytotoxicity were evaluated by MTS and CellTox Green assays, respectively. Cell cycle distribution was analyzed cytometrically after propidium iodide staining. Annexin V binding to externalized phosphatidylserine and analysis of mitochondrial potential allowed the assessment of apoptosis. Glucose uptake and lactate release were evaluated luminometrically. Additionally, the viability of cells in spheroids was analyzed based on ATP content. The Akt-kinase inhibitor showed significant cytotoxicity toward primary cancer cells. Moreover, its pro-apoptotic effects were enhanced by Wnt-pathway inhibitors. The activity of Akt inhibitor was even higher (by twofold) in 3D spheroids in comparison to cells grown in monolayer. The synergistic reduction in the growth of spheroids was observed between Akt inhibitor and IWP-O1. Reduced glucose consumption may play a part in the combinatorial effects of these chemicals. The results point to the therapeutic potential of the combinatorial use of Wnt inhibitors together with Akt inhibitors in HNSCC.

Curbing the Deregulation of Glycosylation in Tongue Carcinoma Cells with Natural Compounds.

Aberrant glycosylation has been recently considered as a major hallmark of cancer. Furthermore, we have reported that aberrant glycosylation, mainly sialylation and fucosylation, plays a major role in oral cancer progression and metastasis. In the present study, we evaluated the role of tobacco compounds (4-NQO, NNK, Benzopyrene), natural compounds (Curcumin, Butein and Piceatannol) and commonly used chemotherapeutic compound (Cisplatin) on sialylation and fucosylation transcript levels in the tongue cancer cell line (SAS). The SAS cells were treated with the tobacco compounds, natural compounds and Cisplatin after obtaining their IC50 values using MTT assay. After 24 hr treatment of the compounds, RNA was isolated from the cells and converted to cDNA. RT-qPCR was performed for mRNA expression of glycosylation transcripts. The treatment of tobacco compounds on the SAS cells resulted in increased mRNA levels of ST3GAL1, NEU3, FUT5 and FUT6 in a dose-dependent manner. The treatment of Curcumin and Butein resulted in lower mRNA levels of FUT8, whereas dose-dependent higher mRNA levels of FUT3 were also observed after the treatment of Curcumin. SAS cells exhibited a dose-dependent decrease in ST3GAL2, FUT5 and FUT8 mRNA after Piceatannol treatment. Furthermore, Cisplatin treatment on the SAS cells resulted in increased mRNA levels of FUT3 as the concentration increased from 100 μM to 200 μM. While, treatment of Cisplatin resulted in decreased mRNA levels of ST3GAL2, ST3GAL3, FUT5 and FUT8 in a dose-dependent manner. All together, the data revealed Piceatannol as a potent synergistic for Cisplatin to target the altered glycosylation for better treatment management of tongue carcinoma. The study provides a normal approach of targeting aberrant glycosylation with natural compounds, which may open the possibility of newer therapeutic strategies using natural compounds alone or in combination with other conventional therapies.

Individual and Combined Treatments with Methylated Resveratrol Analogue DMU-214 and Gefitinib Inhibit Tongue Cancer Cells Growth via Apoptosis Induction and EGFR Inhibition.

The methylated resveratrol analogue 3′-hydroxy-3,4,5,4′-tetramethoxystilbene (DMU-214) has been revealed to exert the anti-cancer activity by a block of the cell cycle at the G2/M phase, apoptosis induction, and metastasis inhibition. These biological events may be involved in crosstalk with the epidermal growth factor receptor (EGFR), which belongs to the ErbB family of receptor tyrosine kinases. Several cancer therapeutic approaches employ small molecules capable of inhibiting tyrosine kinases (e.g., gefitinib). According to more recent reports, combining gefitinib with chemotherapeutics, such as cisplatin, seems to be more effective than monotherapy. The present study aimed to assess the molecular mechanism of the potential anti-proliferative activity of individual and combined treatments with DMU-214 and gefitinib in SCC-25 and CAL-27 human tongue cancer cell lines. We showed for the first time the anti-cancer effects of DMU-214, gefitinib, and their combination in tongue cancer cells triggered via cell cycle arrest, apoptosis induction, and inhibition of the EGFR signaling pathway. The anti-proliferative effects of DMU-214 and gefitinib are also suggested to be related to the EGFR and EGFRP (phosphorylated epidermal growth factor receptor) expression status since we found significantly weaker cytotoxic activity of the compounds tested in SCC-25 cells, which overexpressed EGFR and EGFRP proteins.

MMP8 increases tongue carcinoma cell\u2013cell adhesion and diminishes migration via cleavage of anti-adhesive FXYD5

Matrix metalloproteinases (MMPs) modify bioactive factors via selective processing or degradation resulting in tumour-promoting or tumour-suppressive effects, such as those by MMP8 in various cancers. We mapped the substrates of MMP8 to elucidate its previously shown tumour-protective role in oral tongue squamous cell carcinoma (OTSCC). MMP8 overexpressing (+) HSC-3 cells, previously demonstrated to have reduced migration and invasion, showed enhanced cell-cell adhesion. By analysing the secretomes of MMP8 + and control cells with terminal amine isotopic labelling of substrates (TAILS) coupled with liquid chromatography and tandem mass spectrometry (LC-MS/MS), we identified 36 potential substrates of MMP8, including FXYD domain-containing ion transport regulator 5 (FXYD5). An anti-adhesive glycoprotein FXYD5 has been previously shown to predict poor survival in OTSCC. Cleavage of FXYD5 by MMP8 was confirmed using recombinant proteins. Furthermore, we detected a loss of FXYD5 levels on cell membrane of MMP8 + cells, which was rescued by inhibition of the proteolytic activity of MMP8. Silencing (si) FXYD5 increased the cell-cell adhesion of control but not that of MMP8 + cells. siFXYD5 diminished the viability and motility of HSC-3 cells independent of MMP8 and similar effects were seen in another tongue cancer cell line, SCC-25. FXYD5 is a novel substrate of MMP8 and reducing FXYD5 levels either with siRNA or cleavage by MMP8 increases cell adhesion leading to reduced motility. FXYD5 being a known prognostic factor in OTSCC, our findings strengthen its potential as a therapeutic target.

Carbon Ion Irradiation Enhances the Anti-tumor Efficiency in Tongue Squamous Cell Carcinoma via Modulating the FAK Signaling.

Oral cancer is a very aggressive disease with high rates of recurrence and metastasis. This study aimed at addressing how efficiently tongue cancer is suppressed after carbon ion irradiation. Here, the close relationship between upregulated expression of focal adhesion kinase (FAK) and high metastatic status in tongue squamous cell carcinoma patients was validated using bioinformatics and immunohistochemical analyses. Our data indicated that FAK suppression significantly enhanced the killing effect induced by irradiation in the tongue cancer cell line CAL27, as evidenced by increased apoptotic induction and reduced colony formation. More importantly, in FAK-deficient cells, carbon ion irradiation was shown to remarkably inhibit migration and invasion by delaying wound healing and slowing down motility. Further studies revealed that irradiation exposure caused disorganization of the actin cytoskeleton and reduced cell adhesive energy in FAK-deficient cells. Moreover, carbon ion treatment, in combination with FAK silencing, markedly blocked the phosphorylation levels of FAK, and paxillin, which partly contributed to the reduced motility of tongue squamous cell carcinoma CAL27 cells. Collectively, these results suggest that the prominent obstructing role of carbon ion irradiation in the growth inhibition and metastatic behavior of tumors, including attenuation of cell adhesiveness, motility, and invasiveness, could be distinctly modulated by FAK-mediated downstream pathways.

Mutation profiles of oral squamous cell carcinoma cells

Somatic mutation is associated with the occurrence, development and recurrence of oral cancer. Oral squamous cell carcinoma cell lines have been widely used in oral cancer research. So it's important to understand their genetic background, especially the mutation profile. Using the data of The Catalogue Of Somatic Mutations In Cancer (COSMIC), we analyzed the mutation characteristics of six tongue squamous cell carcinoma cell lines, identified the most common mutation cancer genes in oral squamous cell carcinoma, and compared these genes with those in colon cancer and lung cancer. Six tongue cancer cells have similar mutation spectrum in the coding region, of which C > T transition is the most common mutation, mainly located in the context of CpG dinucleotides. Profiles of mutation genes vary in different tongue cancer cell lines and TP53 is the most common mutation gene, followed by CDKN2A, KMT2D, and LRP1B. The 20 most common mutation genes in oral cancer are different from those in colon cancer and lung cancer, although TP53 is the most common mutation gene in these three cancers. The mutation characteristics of tongue cancer cell lines and mutation gene profiles of oral cancer provide valuable information for the study of oral cancers.