Oral Squamous Cell Carcinoma Cells Research Articles

Abstract PR008: Cross-talk between metastatic cells and host systems: Neutrophil metabolic adaptation, immune profiling, and systemic metabolic shifts in tumor progression and cachexia

Abstract Oral squamous cell carcinoma (OSCC) is a prevalent type of head and neck cancer with a high mortality rate, partly due to late diagnosis often accompanied by metastasis. Cachexia, a complex syndrome marked by severe weight loss and muscle wasting, frequently accompanies advanced cancers including OSCC. Notably, 50-70% of OSCC patients exhibit cachexia at diagnosis, which persists post-treatment, hinting at a metastatic contribution to this syndrome. One significant challenge in studying cancer cachexia is the lack of well-characterized pre-clinical models that accurately reflect human disease. Traditional mouse models often involve subcutaneously transplanted cells, which fail to mimic the natural tumor-host interactions and metastatic progression seen in patients. These models do not typically exhibit metastasis and differ significantly from the genetic and molecular landscape of human cancers. To address these limitations, we developed a syngeneic mouse model by orthotopically transplanting MOC2 murine OSCC cells into the tongues of B6J mice, thereby closely mimicking the tumor microenvironment and metastatic behavior of human OSCC. By enhancing metastasis with a palm-enriched high-fat diet, we observed progressive tumor growth, metastasis, and body weight loss, independent of food intake reduction, indicating metabolic dysregulation rather than anorexia. Comprehensive analyses, including single-cell RNA sequencing (scRNAseq) of immune cells and transcriptomic and metabolomic profiling of tumor and host tissues, identified significant gene expression changes associated with metastasis and cachexia. Enhanced metastasis correlated with lipid metabolism changes in lung metastases, suggesting that metastatic cells exploit lipids for growth. Further, immune profiling revealed neutrophils' metabolic adaptation in metastasis, with implications for both tumor progression and cachexia. Targeting key metabolic and inflammatory pathways in tumor and immune cells holds potential for mitigating metastasis and cachexia. Early-stage serum metabolomics indicated systemic metabolic shifts, emphasizing the need to understand the interplay between tumor metastasis and host metabolism. These findings underscore the complex mechanisms underlying OSCC-induced cachexia, and the need for new targeted therapeutic strategies to disrupt this lethal synergy between cancer progression and metabolic deterioration of the host. Citation Format: Blanca Majem, Josefina Martin, Liudmila Shevkova, Claudia Bigas, Gloria Pascual, Salvador Aznar-Benitah. Cross-talk between metastatic cells and host systems: Neutrophil metabolic adaptation, immune profiling, and systemic metabolic shifts in tumor progression and cachexia [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr PR008.

LINC01614 Promotes Oral Squamous Cell Carcinoma by Regulating FOXC1

Background: Long non-coding RNAs (lncRNAs) are pivotal mediators during the development of carcinomas; however, it remains to be investigated whether lncRNAs are implicated in oral squamous cell carcinoma (OSCC). Methods: In this study, quantitative real-time PCR was conducted for detecting the expression of LINC01614 in OSCC cell lines. The biological functions of LINC01614 were assessed by loss- and gain-of-function experiments conducted both in vivo and in vitro. Cellular proliferation, migration, and invasion were investigated herein, and dual luciferase reporter assays were additionally performed to explore the relationships among LINC01614, miR-138-5p, and Forkhead box C1 (FOXC1). Results: The research presented herein revealed that OSCC cells express high levels of LINC01614. Functional experiments employing cellular and animal models demonstrated that LINC01614 knockdown repressed the malignant phenotypes of OSCC cells, including their growth, invasiveness, and migration. Further investigation revealed that LINC01614 absorbs miR-138-5p miRNA by functioning as a competing endogenous RNA to downregulate the abundance of FOXC1. Conclusions: The findings revealed that LINC01614 contributes to the progression of OSCC by targeting the FOXC1 signaling pathway. The study provides insights into a novel mechanistic process to regulate the development of OSCC, and established a possible target for the therapeutic management of OSCC.

AEBP1 is a negative regulator of skeletal muscle cell differentiation in oral squamous cell carcinoma

The tumor microenvironment plays a pivotal role in cancer development. We recently reported that in oral squamous cell carcinoma (OSCC), adipocyte enhancer-binding protein 1 (AEBP1) is abundantly expressed in cancer-associated fibroblasts (CAFs), leading to CAF activation and inhibition of CD8 + T cell infiltration. In the present study, we investigated whether AEBP1 contributes to the destruction and atrophy of muscle tissues in OSCC. By analyzing human skeletal muscle myoblasts (HSMMs), we found that AEBP1 is downregulated during muscle cell differentiation. Transcriptome analysis revealed that AEBP1 knockdown significantly upregulates myogenesis-related genes in HSMMs, and qRT-PCR and western blot analyses confirmed the induction of muscle-related genes, including MYOG, in HSMMs after AEBP1 knockdown. Conversely, ectopic expression of AEBP1 strongly suppressed myogenesis-related genes in HSMMs. Notably, indirect co-culture of HSMMs with OSCC cells led to AEBP1 upregulation and robust suppression of muscle-related genes in HSMMs. Treatment with TGF-β1 also upregulated AEBP1 and suppressed expression of muscle-related genes in HSMMs. Our findings suggest that AEBP1 is a negative regulator of skeletal muscle cell differentiation and that OSCC cells inhibit muscle cell differentiation, at least in part, by inducing AEBP1.

Targeting the EGFR and Spindle Assembly Checkpoint Pathways in Oral Cancer: A Plausible Alliance to Enhance Cell Death

Background/Objectives: Head and neck cancer (HNC) is among the most common cancer types globally, with its incidence expected to increase significantly in the coming years. Oral squamous cell carcinoma (OSCC), the predominant subtype, exhibits significant heterogeneity and resistance to treatment. Current therapies, including surgery, radiation, and chemotherapy, often result in poor outcomes for advanced stages. Cetuximab, an EGFR inhibitor, is widely used but faces limitations. This study explores the combined inhibition of EGFR and mitotic proteins to enhance treatment efficacy. Methods: We analyzed the effects of co-treating OSCC cells with small molecules targeting MPS-1 (BAY1217389), Aurora-B (Barasertib), or KSP (Ispinesib), alongside Cetuximab. The rationale is based on targeting EGFR-mediated survival pathways and the mitotic checkpoint, addressing multiple cell cycle phases and reducing resistance. Results: Our findings indicate that inhibiting MPS-1, Aurora-B, or KSP enhances Cetuximab’s therapeutic potential, promoting increased cancer cell death. Additionally, we examined EGFR, MPS-1, Aurora-B, and KSP expression in OSCC patient samples, revealing their clinicopathologic significance. Conclusions: This combinatorial approach suggests a promising strategy to improve treatment outcomes in OSCC.

DEAD/H-box helicase 11 is transcriptionally activated by Yin Yang-1 and accelerates oral squamous cell carcinoma progression.

Oral squamous cell carcinoma (OSCC) is the most common oral malignancy. DEAD/H-box helicase 11 (DDX11), a DNA helicase, has been implicated in the progression of several cancers. Yet, the precise function of DDX11 in OSCC is poorly understood. The DDX11 expression in OSCC cells and normal oral keratinocytes was evaluated in the Gene Expression Omnibus database (GSE146483 and GSE31853). SCC-4 and CAL-27 cells expressing doxycycline-inducible DDX11 or DDX11 shRNA were generated by lentiviral infection. The role of DDX11 in OSCC cells was determined by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, colony formation assay, flow cytometry assay, TUNEL staining, and western blot. The effects of DDX11 on tumor growth were explored in a xenograft nude mouse model. The relationship between DDX11 and transcription factor Yin Yang-1 (YY1) was researched using the dual luciferase report assay and chromatin immunoprecipitation assay. DDX11 expression was significantly upregulated in OSCC cells. Knockdown of DDX11 inhibited cell proliferation, induced cell cycle arrest, and suppressed PI3K-AKT pathway, while DDX11 overexpression showed opposite effects. The number of apoptotic cells was increased in DDX11 silenced cells. DDX11 upregulation or knockdown accelerated or suppressed tumor growth in vivo, respectively. Moreover, the YY1 bound and activated the DDX11 promoter, resulting in increasing DDX11 expression. Forced expression DDX11 reversed the anticancer effects of YY1 silencing on OSCC cells. DDX11 has tumor-promoting function in OSCC and is transcriptionally regulated by YY1, indicating that DDX11 may serve as a potential target for the OSCC treatment.

WNT7B promotes cancer progression via WNT/β-catenin signaling pathway and predicts a poor prognosis in oral squamous cell carcinoma

BackgroundWNT7B is a glycoprotein that plays a crucial role in tumorigenesis. This study aimed to investigate the role of WNT7B in oral squamous cell carcinoma (OSCC).MethodsBioinformatic databases, immunohistochemistry, a real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay were used to detect WNT7B expression in OSCC. The clinical and prognostic importance of WNT7B expression was evaluated. WNT7B expression was examined in oral leukoplakia and carcinoma induced by 4-nitroquinoline 1-oxide in mice. Loss- and gain-of-function analyses were performed to elucidate the role of WNT7B in OSCC cells. Subcutaneous tumor model was established to observe the effects of WNT7B on tumor growth. Co-Immunoprecipitation was used to explore the Frizzled receptors that WNT7B may bind to.ResultsWNT7B upregulated in OSCC and associated with lymph node metastasis, perineural invasion, and an unfavorable prognosis in patients with OSCC. A gradual increased in WNT7B expression during the malignant progression of OSCC. WNT7B promoted cell proliferation, migration, invasion, while silencing WNT7B abolished these effects. Knocking down the expression of WNT7B inhibits tumor growth in vivo. WNT7B functions by binding to the Frizzled 7 receptor and facilitates the nuclear translocation of β-catenin.ConclusionsWNT7B contributes to the progression of OSCC by modulating the WNT/β-catenin signaling pathway. These findings highlight the potential of WNT7B as a novel prognostic biomarker and promising therapeutic target for OSCC.

Nimbolide Induces Cell Apoptosis via Mediating ER Stress-Regulated Apoptotic Signaling in Human Oral Squamous Cell Carcinoma.

Human oral squamous cell carcinoma (OSCC) poses a significant health challenge in Asia, with current therapeutic strategies failing to improve the survival rates for OSCC patients sufficiently. To elucidate the effects of Nimbolide on OSCC cell proliferation and apoptosis, we performed a series of experiments, including cell proliferation assays, annexin V/PI assays, and cell cycle analysis. We further investigated nimbolide's role in modulating endoplasmic reticulum (ER) stress, reactive oxygen species (ROS) production, and mitochondrial dysfunction using flow cytometry. Additionally, Western blotting was used to detect apoptosis-related protein expression. Our findings reveal that nimbolide exerts its anti-proliferative effects on OSCC cells by inducing apoptosis. The nimbolide increased intracellular ROS levels and acceleration of cellular calcium accumulation, respectively promoting endoplasmic reticulum stress and cancer cell apoptosis. Furthermore, nimbolide activates the caspase cascade by altering the mitochondrial membrane potential and apoptotic protein expression, thereby inhibiting the viability of tumor cells. Our data show that Nimbolide suppresses tumor growth through the induction of ROS production, ER stress, and mitochondrial dysfunction, resulting in apoptosis in OSCC cells. Overall, our study highlights nimbolide as a potential natural compound for OSCC therapy.

CHRDL1 inhibits OSCC metastasis via MAPK signaling-mediated inhibition of MED29

BackgroundCHRDL1 belongs to a novel class of mRNA molecules. Nonetheless, the specific biological functions and underlying mechanisms of CHRDL1 in oral squamous cell carcinoma (OSCC) remain largely unexplored.MethodsRT-qPCR and immunohistochemical staining were employed to assess the mRNA and protein expression levels of the MED29 gene in clinical samples of OSCC. Additionally, RT-qPCR and Western Blot analyses were conducted to investigate the mRNA and protein expression levels of the MED29 gene specifically in OSCC. The impact of MED29 on epithelial-mesenchymal transition (EMT), invasion, and migration of OSCC was evaluated through scratch assay, transwell assay, and immunofluorescence staining. Furthermore, wound healing assay and Transwell assay were utilized to examine whether CHRDL1 influences the malignant behavior of OSCC by modulating MED29 in vitro. The regulatory role of CHRDL1 on MED29 was further elucidated in vivo through a tail vein lung metastasis model in nude mice.ResultsMED29 expression was elevated in tumor tissues of OSCC patients compared with adjacent cancer tissues. Moreover, in CAL27 and SCC25 cell lines, MED29 was upregulated and associated with increased cell migration and invasion abilities. Overexpression of MED29 facilitated EMT in OSCC cell lines, whereas knockdown of MED29 impeded EMT, resulting in diminished cell migration and invasion capacities. CHRDL1 exerted inhibitory effects on the expression of MED29, thereby suppressing EMT progression and consequently restraining the invasion and migration of OSCC cells. Furthermore, CHRDL1 mediated the inhibition of migration of OSCC cell lines to the OSCC through its regulation of MED29.ConclusionsMED29 facilitated the epithelial-mesenchymal transition process in OSCC, thereby promoting migration and invasion. On the other hand, CHRDL1 exerted inhibitory effects on the invasion and metastasis of OSCC by suppressing MED29 through the inhibition of the MAPK signaling pathway.

Exploring the anticancer and antioxidant potential of gold nanoparticles synthesized from Pterocarpus marsupium bark extract against oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a disease of significant concern with higher mortality rates. Conventional treatment approaches have several drawbacks, leading to the opening of new research avenues in the field of nanoparticle-based cancer therapeutics. The study aimed at the synthesis of gold nanoparticles (Pm-AuNPs) from the aqueous bark extract of Pterocarpus marsupium, followed by its characterization and in vitro anticancer evaluation against OSCC. The synthesized Pm-AuNPs were characterized using UV–visible spectroscopy, particle size analyser, zeta potential, FTIR and SEM techniques. The anticancer potential of the Pm-AuNPs was evaluated against OSCC cell lines (SCC29b, SSC154 and OECM-1) through in vitro assays. The IC50 value was found to be 25 ± 1.2, 45 ± 1.5 and 75 ± 2.1 µg/mL for the three OSCC cell lines, elucidating Pm-AuNPs cytotoxic effects and mechanism of action. Intracellular ROS and SOX detection, mitochondrial transmembrane potential analysis and apoptosis detection were used to confirm the activity of Pm-AuNPs against OSCC. Acute toxicity studies on Wistar rats confirmed the non-toxic nature of the Pm-AuNPs at a higher dose concentration up to 2000 mg/kg body weight. The findings underscore Pm-AuNPs as promising candidates for future anticancer therapeutics, providing insights into their mechanism of action and therapeutic efficacy against OSCC.

Metal Polyphenol Nanoparticle-Based Chemo/Ferroptosis Synergistic Therapy for the Treatment of Oral Squamous Cell Carcinoma.

Despite the use of surgical resection and chemotherapy in the clinical treatment of oral squamous cell carcinoma (OSCC), the 5-year survival rates of advanced patients are low. Therefore, more efficient strategies are urgently needed. Herein, a chemo/ferroptosis synergistic therapeutic system-DMEFe nanoparticles (NPs) is established for the treatment of OSCC. To create this system, the chemotherapeutic agent doxorubicin (DOX) was loaded into mesoporous silica nanoparticles and further coated with a pH-sensitive metal polyphenol (iron ion and epigallocatechin gallate). These nanoparticles displayed excellent pH-sensitive drug-control release properties, and the release ratio of DOX at pH 5.5 was twice as high than that at pH 7.4. Additionally, DMEF NPs were effectively taken up by the OSCC cell line SSC-25, which greatly impeded the proliferation of these cells. Notably, these nanoparticles increased the intracellular level of reactive oxygen species and effectively exhibited cytotoxity effects. The mechanistic results proved that DMEFe NPs regulated the expression of ferroptosis-related genes to induce ferroptosis of SSC-25 cells. Eventually, this chemo/ferroptosis therapeutic system exhibited remarkable antitumor effects and provided a novel strategy for the treatment of OSCC.

Porphyromonas gingivalis Promotes Oral Squamous Cell Carcinoma Progression by Modulating Autophagy.

Porphyromonas gingivalis (P. gingivalis) is a keystone periodontal pathogen associated with various gastro-intestinal tract cancers. However, whether P. gingivalis can promote oral squamous cell carcinoma (OSCC) and the underlying mechanism associated with such promotion remain unclear. In this study, OSCC xenograft models were used to evaluate the effects of P. gingivalis on tumor progression. The functional studies were done on several OSCC cell lines invitro. P. gingivalis-specific 16S rRNA fluorescent insitu hybridization (FISH) was used to test its prevalence in clinical samples. We found that P. gingivalis increased tumor volume and tumor growth in OSCC nude models. Functional studies demonstrated that P. gingivalis inhibited the apoptosis of OSCC cells by promoting cellular autophagy. P. gingivalis was more prevalent in FISH samples from patients with OSCC than from patients with leukoplakia or healthy subjects (70% vs. 47.2% vs. 33.3%, p = 0.045 and p < 0.001, respectively). These data suggest that P. gingivalis plays an accelerating role in OSCC progression and contributes to OSCC by enhancing the autophagy pathway to reduce carcinoma apoptosis.

TNO155 is a selective SHP2 inhibitor to target PTPN11-dependent oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is known to be driven by multiple intricated receptor tyrosine kinases (RTKs) including EGFR, PI3K/AKT and MAPK signaling pathways. However, whilst targeting EGFR with cetuximab has been approved for the treatment of OSCC, other single-agent inhibitors of the RTKs have shown modest effects in improving survival. From the genome-wide CRISPR/Cas9 screen on 21 OSCC cell lines, we have identified PTPN11 among the top essential genes in OSCC. PTPN11 encodes for SHP2, a phosphatase that acts as a master signal transducer, downstream of various RTKs. Although PTPN11 overexpression has been reported in OSCC, little is known about its role as an essential gene for OSCC survival and its potential as a therapeutic target. Herein, we confirmed that PTPN11 is an essential gene in OSCC where its deletion significantly impacted cell survival. We evaluated three SHP2 inhibitors on 21 OSCC cell lines and found TNO155 to be significantly associated with CRISPR dependency score. We showed that TNO155 caused dose-dependent suppression on p-ERK and p-MEK, and suppresses the JAK/STAT pathway via downregulating p-JAK1, p-STAT1, p-STAT3. Furthermore, we confirmed that the combination of the mTOR inhibitor, everolimus with TNO155 is synergistic in OSCC. In summary, PTPN11 is a promising therapeutic target in OSCC that can be selectively targeted by SHP2 inhibitor such as TNO155. Our findings on the use of mTOR inhibitor, everolimus to overcome resistance to TNO155 are essential to inform on next phases of clinical trials which is warranted for the treatment of OSCC.

MicroRNA‑374a‑5p/ANLN axis promotes malignant progression of Oral squamous cell carcinoma

Background: Recent research has revealed a significant association between Anillin (ANLN) and miR-374a‑5p with the progression of tumors. Additionally, bioinformatics analysis indicated an inverse relationship in transcript expression levels between ANLN and miR-374a-5p. However, the specific mechanisms driving the miR-374a-5p/ANLN signaling axis in oral squamous cell carcinoma (OSCC) have not been thoroughly explored. Methods: ANLN and miR-374a‑5p expression were evaluated within OSCC cell lines and tissues by RT-qPCR. Using bioinformatics databases, it has been demonstrated that the ANLN gene could be a target of miR-374a-5p. MiR-374a‑5p and ANLN correlation could be assessed via the dual-luciferase reporter assay and western blotting techniques. Functional studies were employed to investigate the behavioral patterns of miR-374a‑5p within OSCC cells. Results: miR-374a‑5p expression could be remarkably downregulated within both OSCC tissues and cells, coinciding with high ANLN expression. ANLN was a specific target gene for miR-374a‑5p by luciferase function assay. The expression of miR-374a‑5p could serve as a diagnostic biomarker and independently predict a poor prognosis in patients with OSCC, and the counteractive effect of upregulating miR-374a‑5p was observed on the proliferative, migratory, and invasive capabilities of OSCC cells. Conclusions: The findings suggest that the miR-374a‑5p/ANLN signaling axis potentially modulates the advancement of OSCC, and miR-374a‑5p may serve as potential therapeutic targets of oral cancer.

Potential role of heteroplasmic mitochondrial DNA mutations in modulating the subtype-specific adaptation of oral squamous cell carcinoma to cisplatin therapy

Cancer cells are constantly evolving to adapt to environmental changes, particularly during exposure to drug treatment. In this work, we aimed to characterize genetic and epigenetic changes in mitochondrial DNA (mtDNA) that may increase the resistance of oral squamous cell carcinoma (OSCC) to cisplatin. We first derived drug-resistant cells from two human OSCC cell lines, namely SAS and H103, by continual cisplatin treatments for about 4 months. To determine mtDNA changes induced by cisplatin, we performed nanopore sequencing and quantitative polymerase chain reaction analysis of mtDNA extracted from the cells pre- and post-treatment. We also assessed the mitochondrial functions of the cells and their capacity to generate intracellular reactive oxygen species (ROS). We found that in the cisplatin-resistant cells derived from SAS, there was a reduction in mtDNA content and significant enrichment of a m.3910G > C mutation in the MT-ND1 gene. However, such changes were not detected in cisplatin-resistant H103 cells. The cisplatin treatment also altered methylation patterns in both SAS and H103 cells and decreased their sensitivity to ROS-induced cytotoxicity. We suggest that the sequence alterations and epigenetic changes in mtDNA and the reduction in mtDNA content could be key drivers of cisplatin resistance in OSCC. These mtDNA alterations may participate in cellular adaptation that serves as a response to adverse changes in the environment, particularly exposure to cytotoxic agents. Importantly, the observed mtDNA changes may be influenced by the distinct genetic landscapes of various cancer subtypes. Overall, this study reveals significant insights into cisplatin resistance driven by complex mtDNA dynamics, particularly in OSCC. This underscores the need for targeted therapies tailored to the genetic profiles of individual OSCC patients to improve disease prognosis.

H3K27 Acetylation-Activated GLDC Accelerated the Advancement of Oral Squamous Cell Carcinoma by Suppressing the p53 Signaling Pathway.

Glycine decarboxylase (GLDC) has been identified to be dysregulated and plays pivotal roles in various cancers. Besides, studies have suggested that GLDC expression is elevated in oral squamous cell carcinoma (OSCC) and associated with a worse prognosis, but the precise role and molecular mechanism of GLDC in OSCC remain unexplored. The current study first confirmed the high expression of GLDC in OSCC and its correlation with worse survival in patients with OSCC. By knocking down GLDC, it was discovered that the growth and colony formation of OSCC cells, as well as the development of xenograft tumors, were effectively suppressed. In addition, GLDC deficiency inhibited the migration and invasion of OSCC cells in vitro through regulating EMT markers and attenuated lung metastasis in vivo. Mechanistically, GLDC was found to affect the activity of the p53 signaling pathway. GLDC depletion retarded the progression of OSCC by activating the p53 signaling pathway. Moreover, p300 co-functioned with TFAP2A to induce acetylation of GLDC, which resulted in the upregulation of GLDC in OSCC. To conclude, acetylation-induced GLDC upregulation facilitated the tumorigenesis and metastasis of OSCC by its inhibition of the activity of the p53 signaling pathway.

Energy Metabolic Profile in Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma: A Preliminary Landscape of Warburg Effect in Oral Cancer.

We hypothesized that cell energy metabolic profiles correlate with normal, dysplastic, and tumor cell/tissue statuses and may be indicators of aggressiveness in oral squamous cell carcinoma (OSCC) cells. The energy-related proteins that were differentially expressed in human OSCC fragments (n = 3) and their adjacent epithelial tissue (TAE) were verified using mass spectrometry (MS). Immunohistochemistry for 4-hydroxynonenal (4-HNE) was performed to evaluate the oxidative stress patterns in OSCC (n = 10), epithelial dysplasia (n = 9), and normal epithelial (n = 4) biopsies. The metabolic energy profile of OSCC aggressiveness was investigated in human OSCC cell lines with different levels of epithelial-mesenchymal transition proteins. The genes associated with the proteins found by MS in this study were analyzed using survival analysis (OS), whereas the genes associated with a poorer prognosis were analyzed using context-specific expression, Gene Ontology (GO) and Cancer Hallmarks for function enrichment analysis. The rationale for all experimental approach was to investigate whether the variation in energy metabolism profile accompanies the different phenotypes (from epithelial to mesenchymal) during the epithelial-mesenchymal transition. All OSCC fragments exhibited an increase in glycolysis-related proteins and a decrease in mitochondrial activity compared to the TAE region (p < 0.05), probably due to the downregulation of pyruvate dehydrogenase and antioxidant proteins. Additionally, the OSCC cell lines with a mesenchymal profile (SCC4, SCC9, and SCC25) had a lower mitochondrial mass and membrane potential and generated lower levels of reactive oxygen and nitrogen species than the TAE region. When we analyzed 4-HNE, the reactive species levels were increased in the epithelial regions of OSCC and potentially malignant lesions. A decrease in the levels of 4-HNE/reactive species was observed in the connective tissue underlying the dysplastic regions and the OSCC invasion zone. Based on this scenario, aggressive OSCC is associated with high glycolytic and oxidative metabolism and low mitochondrial and antioxidant activities, which vary according to the differentiation level of the tumor cells and the stage of carcinogenesis.

LncRNA PCBP1-AS1 suppresses cell growth in oral squamous cell carcinoma by targeting miR-34c-5p/ZFP36 axis.

Oral squamous cell carcinoma (OSCC) is the most frequently diagnosed oral malignancy and poses a great threat to public health. According to bioinformatics analysis, long noncoding RNA PCBP1-AS1 is downregulated in OSCC. In this work, the functions and mechanism of PCBP1-AS1 in OSCC were further investigated. PCBP1-AS1 expression in OSCC cells was measured by quantitative polymerase chain reaction. Cell viability and proliferation were detected using CCK-8 assays and colony-forming assays. TUNEL assays as well as flow cytometry analyses were carried out to detect OSCC cell apoptosis. Binding relationship between PCBP1-AS1 and miR-34c-5p or that between miR-34c-5p and ZFP36 in OSCC cells was identified using RNA immunoprecipitation assays, RNA pulldown assays, and luciferase reporter assays. Experimental results revealed that PCBP1-AS1 was downregulated in OSCC cells. PCBP1-AS1 overexpression hampered cell proliferation and enhanced cell apoptosis in OSCC. PCBP1-AS1 interacted with miR-34c-5p in OSCC and negatively regulated miR-34c-5p. ZFP36 3'untranslated region was targeted by miR-34c-5p. PCBP1-AS1 positively regulated ZFP36 expression. ZFP36 silencing abrogated the suppressive impact of PCBP1-AS1 on OSCC cell growth. In summary, PCBP1-AS1 suppresses cell growth in OSCC by upregulating ZFP36 through interaction with miR-34c-5p.

Optimization of the Treatment of Squamous Cell Carcinoma Cells by Combining Photodynamic Therapy with Cold Atmospheric Plasma

Actinic keratosis (AK) is characterized by a reddish or occasionally skin-toned rough patch on sun-damaged skin, and it is regarded as a precursor to squamous cell carcinoma (SCC). Photodynamic therapy (PDT), utilizing 5-aminolevulinic acid (ALA) along with red light, is a recognized treatment option for AK that is limited by the penetration depth of light and the distribution of the photosensitizer into the skin. Cold atmospheric plasma (CAP) is a partially ionized gas with permeability-enhancing and anti-cancer properties. This study analyzed, in vitro, whether a combined treatment of CAP and ALA-PDT may improve the efficacy of the treatment. In addition, the effect of the application sequence of ALA and CAP was investigated using in vitro assays and the molecular characterization of human oral SCC cell lines (SCC-9, SCC-15, SCC-111), human cutaneous SCC cell lines (SCL-1, SCL-2, A431), and normal human epidermal keratinocytes (HEKn). The anti-tumor effect was determined by migration, invasion, and apoptosis assays and supported the improved efficacy of ALA-PDT in combination with CAP. However, the application sequence ALA-CAP–red light seems to be more efficacious than CAP-ALA–red light, which is probably due to increased intracellular ROS levels when ALA is applied first, followed by CAP and red light treatment. Furthermore, the expression of apoptosis- and senescence-related molecules (caspase-3, -6, -9, p16INK4a, p21CIP1) was increased, and different genes of the junctional network (ZO-1, CX31, CLDN1, CTNNB1) were induced after the combined treatment of CAP plus ALA-PDT. HEKn, however, were much less affected than SCC cells. Overall, the results show that CAP may improve the anti-tumor effects of conventional ALA-PDT on SCC cells. Whether this combined application is successful in treating AK in vivo has to be carefully examined in follow-up studies.

The LINC00319 binding to STAT3 promotes the cell proliferation, migration, invasion and EMT process in oral squamous cell carcinoma

BackgroundLong non-coding RNA LINC00319 has been implicated in the progression of various cancers, including oral squamous cell carcinoma (OSCC). While our previous work has revealed some aspects of LINC00319's role in OSCC, including its upregulation and involvement in a competing endogenous RNA (ceRNA) mechanism, the full extent of its functions and regulatory mechanisms in OSCC progression remain to be fully elucidated. ObjectiveThis study aimed to investigate the function of LINC00319 in OSCC and its potential interaction with the STAT3 signaling pathway, thus uncovering novel regulatory mechanisms and therapeutic targets. MethodsBioinformatics analysis was performed using TCGA data to evaluate LINC00319 expression in OSCC tissues and its correlation with STAT3 signaling. The direct binding between LINC00319 and STAT3 was examined by RNA pull-down, FISH, and RIP assays. Functional experiments, including CCK-8, transwell migration and invasion assays, and western blot analysis of EMT markers and STAT3 pathway activation, were conducted to assess the effects of LINC00319 on OSCC cell behaviors and its interaction with the STAT3 signaling pathway. In vivo xenograft models were established to validate the role of LINC00319 in tumor growth and STAT3 activation. ResultsLINC00319 expression was significantly upregulated in OSCC tissues compared to normal tissues, and high LINC00319 expression correlated with STAT3 signaling activation. Mechanistically, LINC00319 directly bound to STAT3 protein and promoted its phosphorylation at Tyr705. LINC00319 overexpression enhanced, while its knockdown suppressed, the proliferation, migration, invasion, and EMT of OSCC cells. These oncogenic effects were mediated through STAT3 activation and could be reversed by the STAT3 inhibitor stattic. In vivo experiments further confirmed that LINC00319 silencing inhibited tumor growth and STAT3 phosphorylation. ConclusionThis study uncovers that LINC00319 promotes OSCC tumorigenesis by directly binding to and activating STAT3 signaling. These findings provide new insights into the regulatory mechanisms of STAT3 by long non-coding RNAs and highlight the potential of LINC00319 as a biomarker and therapeutic target in OSCC.

Study on the expression of lncRNA PRKCA-AS1 in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is one of the most malignant tumors in the oral and maxillofacial region, with a poor prognosis. Previous studies have shown that long non-coding RNAs (lncRNAs) play a crucial role in tumor development by regulating the biological behavior of various cancer cells. The aim of this study is to explore the role and potential mechanisms of lncRNA PRKCA-AS1 in OSCC. Real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression levels of lncRNA PRKCA-AS1 in OSCC tissues and cell lines. Cell proliferation, migration and invasion were conducted to assess the biological functions of OSCC cell lines. The expression of lncRNA PRKCA-AS1 in OSCC tissues was higher compared to that of adjacent non-cancerous tissues, and its expression level was associated with the depth of tumor infiltration, lymph node metastasis, and tumor node metastasis (TNM) staging. Compared to the control group of normal human oral keratinocytes (HOK), the expression of lncRNA PRKCA-AS1 was also elevated in OSCC cell lines. Knockdown of lncRNA PRKCA-AS1 significantly affected the proliferation, migration, and invasion ability of OSCC cells. However, when lncRNA PRKCA-AS1 was further overexpressed, changes in cell proliferation and migration ability did not show statistical differences. LncRNA PRKCA-AS1 is highly expressed in OSCC, and its expression level is positively correlated with the depth of tumor infiltration, lymph node metastasis, and TNM staging. LncRNA PRKCA-AS1 is involved in regulating the proliferation, migration, and invasion of OSCC cells.