Apoptosis Of Oral Squamous Cell Carcinoma Cells Research Articles

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.

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.

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.

Mechanism of apoptosis in oral squamous cell carcinoma promoted by cardamonin through PI3K/AKT signaling pathway

Currently, surgical resection remains the primary approach for treating oral squamous cell carcinoma (OSCC), with limited options for effective drug therapy. Cardamonin, a principal compound derived from Myristica fragrans of the Zingiberaceae family, has garnered attention for its potential to suppress the onset and progression of various malignancies encompassing breast cancer, hepatocellular carcinoma, and ovarian cancers. Nevertheless, the involvement of cardamonin in the treatment of OSCC and its underlying mechanisms are yet to be elucidated. This research explored the possible target of cardamonin in treating OSCC via network pharmacological analysis. Subsequently, this research investigated the impact of cardamonin on OSCC cells via in vitro experiments, revealing its capacity to impede the migration, proliferation, and invasion of OSCC cells. Additionally, western blotting analysis demonstrated that cardamonin facilitates apoptosis by regulating the PI3K/AKT pathway. The findings suggest that MMP9 and the PI3K/AKT signaling pathway may serve as the target and pathway of cardamonin in treating OSCC. To summarize, the research findings suggest that cardamonin may facilitate apoptosis in OSCC cells by inhibition of PI3K/AKT pathway activation. These outcomes offer a theoretical basis for the utilization of cardamonin as a natural drug for treating OSCC.

Astilbin Induces Apoptosis in Oral Squamous Cell Carcinoma through p53 Reactivation and Mdm-2 Inhibition.

Oral squamous cell carcinoma (OSCC) is a frequently occurring malignancy in the head and neck region. The most commonly mutated gene in OSCC is the tumor suppressor gene p53 (TP53), linked to lower survival and treatment resistance in OSCC patients. Astilbin is a flavonoid amongst several herbal treatments with a variety of pharmacological actions mainly including antioxidant, anti-inflammatory, and anti-cancer characteristics. This study evaluated the effects of astilbin on proliferation of OSCC cell lines SCC90 and SCC4 (bearing a p53 mutation) in relevance to p53 and Mdm-2 pathways. Astilbin inhibited the proliferation of SCC4 and SCC90 cells in a dose- and time-dependent manner. The IC50 values for both the cell lines were about 75 μM for astilbin. A p53 activator (RITA) was used to determine the effects of astilbin on p53 activity, and the results demonstrated synergistic reduction in cell growth. However, when combined with pifithrin-α (a p53 inhibitor), astilbin demonstrated a strong inhibition of its response. Astilbin reduced the mitochondrial membrane potential in SCC4 cells, which is a sign of apoptotic activity. Astilbin decreased the amounts of Mdm-2 (negative regulator of p53) and increased the expression of the p53 gene and protein. In a p53-dependent manner, astilbin suppressed the ability of SCC4 cells to form colonies and heal wounds. This was followed by the induction of mitochondrial intrinsic apoptosis via the activation of caspases 9 and 3, cleavage of PARP, and the suppression of pro-apoptotic Bid. Astilbin-induced p53-mediated apoptosis in OSCC cells as herbal medicinal ingredients.

The efficacy and potential mechanisms of pyrotinib in targeting EGFR and HER2 in advanced oral squamous cell carcinoma

BackgroundHuman epidermal growth factor receptor 2 (HER2) plays an important role in the progression of multiple solid tumors and induces resistance to epidermal growth factor receptor (EGFR) target treatment. However, the expression status and the clinical significance of HER2 in oral squamous cell carcinoma (OSCC) is still controversial. Pyrotinib (PYR) is a promising novel EGFR/HER2 dual inhibitor, whose efficacy in OSCC has not been determined.Methods57 locally advanced de novo OSCC patients were included in this study to investigate the relationship between the HER2 expression levels and the prognosis by the tissue microarray analysis (TMA). In vitro and in vivo experiments were performed to retrieve the efficacy of PYR in OSCC. The main downstream of HER2 was evaluated by western blotting in OSCC cell lines and xenograft tumors to explore the potential mechanism of PYR.ResultsThis study revealed the primary tumor of OSCC had higher HER2 expression levels. Patients with HER2 overexpression had poor overall survival (P < 0.014) and poor disease free survival (P < 0.042). In vitro, PYR suppressed the proliferation, colony formation and migration of OSCC cells. It also promoted apoptosis of OSCC cells and induced cell cycle arrest. Furthermore, PYR was able to inhibit the occurrence and development of OSCC effectively in vivo. Western blotting revealed that PYR suppressed OSCC by inhibiting the phosphorylation of HER2, AKT and ERK.ConclusionsThis study exhibited the anti-OSCC effects of PYR in vitro and in vivo, and demonstrated PYR inhibited OSCC cells by inducing apoptosis via the HER2/ AKT and ERK pathway. The result of this study also indicated locally advanced OSCC patients might benefit from HER2 assay and EGFR/HER2 dual inhibit treatment.

CKIP-1 silencing suppresses OSCC via mitochondrial homeostasis-associated TFAM/cGAS-STING signalling axis.

Limited effective targets have challenged the treatment of oral squamous cell carcinoma (OSCC). Casein kinase 2 interacting protein 1 (CKIP-1) is a scaffold protein involved in various diseases. However, the role of CKIP-1 in OSCC remains unclear. The aim of this study was to explore the regulatory role of CKIP-1 in OSCC, as well as the involved mechanism. First, higher expression of CKIP-1 in OSCC tissues and cell lines were found. Series of gain- and loss-of-function experiments demonstrated suppressed malignant behaviours and enhanced apoptosis of OSCC cells when CKIP-1 was silenced. Also, inhibited tumour growth in CKIP-1-silenced group were proved. Further, mitochondrial transcription factor A (TFAM) downregulation, increased ROS production, decreased mitochondrial membrane potential and cGAS-STING activation in CKIP-1-silenced group were observed. The involvement of mitochondrial homeostasis-related TFAM/cGAS-STING axis in CKIP-1-silenced OSCC cells was finally demonstrated by tetramethylpyrazine (TMP) that inhibits TFAM degradation. Taken together, our study demonstrated that CKIP-1 silencing could significantly antagonize OSCC via TFAM/cGAS-STING axis, which may provide a candidate target for OSCC treatment.

Erythroblast transformation-specific-related gene promotes metastasis of oral squamous cell carcinoma by transcriptionally upregulating peroxiredoxin 1.

Some studies confirmed that erythroblast transformation-specific-related gene (ERG) may be a pathogenic factor of oral squamous cell carcinoma (OSCC). However, the undergoing molecular mechanism has not been elucidated yet. In this study, the investigation will focus on how the transcription factor ERG modulates the biological behaviors of OSCC. In this study, cancer tissue specimens and corresponding paracancer tissues were collected from 54 patients. Real-time polymerase chain reaction analysis and Western blots were employed to detect the expression of multiple genes. Cell proliferation assays, Transwell, and flow cytometry assay were utilized to detect the proliferation, invasion, and apoptosis of OSCC cell, respectively. Dual luciferase reporter gene and chromatin immunoprecipitation assays were conducted to verify the regulation of ERG on PRDX1. ERG exhibits high expression levels in OSCC. Inhibition of ERG has been shown to effectively suppress the malignant growth of OSCC cells. Moreover, ERG has been found to transcriptionally upregulate the expression of PRDX1. The knockdown of PRDX1 has demonstrated its ability to inhibit the malignant growth of OSCC cells. Interestingly, when PRDX1 is overexpressed, it attenuates the inhibitory effect of si-ERG on the malignant growth of OSCC cells. This suggests that PRDX1 may play a crucial role in mediating the impact of ERG on malignancy in OSCC cells. The transcription factor ERG promotes the expression of PRDX1, which could enhance the proliferation and invasion while inhibiting the apoptosis of OSCC cells.

PAK4 inhibition augments anti-tumour effect by immunomodulation in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumours, warranting novel treatments. Here, we examined the therapeutic efficacy of inhibiting p21 activated kinase 4 (PAK4) in OSCC and determined its immunomodulatory effect by focusing on the enhancement of anti-tumour effects. We examined PAK4 expression in OSCC cells and human clinical samples and analysed the proliferation and apoptosis of OSCC cells following PAK4 inhibition in vitro. We also investigated the effects of in vivo administration of a PAK4 inhibitor on immune cell distribution and T-cell immune responses in OSCC tumour-bearing mice. PAK4 was detected in all OSCC cells and OSCC tissue samples. PAK4 inhibitor reduced the proliferation of OSCC cells and induced apoptosis. PAK4 inhibitor significantly attenuated tumour growth in mouse and was associated with increased proportions of IFN-γ-producing CD8+ T-cells. Furthermore, PAK4 inhibitor increased the number of dendritic cells (DCs) and up-regulated the surface expression of various lymphocyte co-stimulatory molecules, including MHC-class I molecules, CD80, CD83, CD86, and CD40. These DCs augmented CD8+ T-cell activation upon co-culture. Our results suggest that PAK4 inhibition in OSCC can have direct anti-tumour and immunomodulatory effects, which might benefit the treatment of this malignancy.

METTL3 Promotes OSCC Progression by Down-Regulating WEE1 in a m6A-YTHDF2-Dependent Manner.

Oral squamous cell carcinoma (OSCC) is a common and highly lethal epithelial cancer. This study aimed to confirm the role of METTL3 in promoting OSCC and investigate its specific underlying mechanisms. Expression of the METTL3, YTH domain-containing family 2 (YTHDF2), and WEE1 were examined in normal oral epithelial cells and OSCC cells. Cell functions were examined after overexpressing WEE1 in OSCC cells. MeRIP-qPCR analysis was used to detect WEE1 m6A levels in HOK, SCC25, and CAL27 cells. WEE1 and its m6A levels were evaluated in OSCC cells by knocking down METTL3/YTHDF2, assessing the interaction between METTL3/YTHDF2 and WEE1. The impact of METTL3 and YTHDF2 downregulation on WEE1 mRNA stability was also investigated. The tumor weight and volume in a nude mouse model of OSCC after overexpression of WEE1 and YTHDF2 were measured. Expression of Ki-67 and WEE1 in OSCC tissue was detected using immunohistochemistry. Compared to normal oral epithelial cells, METTL3 and YTHDF2 were upregulated in OSCC cells, while WEE1 was downregulated, and there was a negative correlation between WEE1 and METTL3/YTHDF2 expression. WEE1 overexpression inhibited proliferation, invasion, and migration while promoting apoptosis in OSCC cells. METTL3 and YTHDF2 bound to WEE1 mRNA. METTL3/YTHDF2 knockdown increased WEE1 levels and WEE1 mRNA stability. METTL3 inhibition reduced WEE1 m6A levels. Inhibition of METTL3 weakened the interaction between YTHDF2 and WEE1 mRNA. In vivo, overexpression of WEE1 suppressed OSCC development, which was reversed by overexpression of YTHDF2. METTL3 facilitates the progression of OSCC through m6A-YTHDF2-dependent downregulation of WEE1.

The antitumor effects of herbal medicine Triphala on oral cancer by inactivating PI3K/Akt signaling pathway: based on the network pharmacology, molecular docking, in vitro and in vivo experimental validation

BackgroundThis research aimed to investigate the anti-tumor effects and underlying genetic mechanisms of herbal medicine Triphala (TRP) in oral squamous cell carcinoma (OSCC). MethodsThe target genes of Triphala (TRP) in oral squamous cell carcinoma (OSCC) were identified, and subsequent functional enrichment analysis was conducted to determine the enriched signaling pathways. Based on these genes, a protein-protein interaction network was constructed to identify the top 10 genes with the highest degree. Genes deregulated in OSCC tumor samples were identified to be hub genes among the top 10 genes. In vitro experiments were performed to investigate the influence of TRP extracts on the cell metabolic activity, migration, invasion, apoptosis, and proliferation of two OSCC cell lines (CAL-27 and SCC-9). The functional rescue assay was conducted to investigate the effect of applying the inhibitor and activator of an enriched pathway on the phenotypes of cancer cells. In addition, the zebrafish xenograft tumor model was established to investigate the influence of TRP extracts on tumor growth and metastasis in vivo. ResultsThe target genes of TRP in OSCC were prominently enriched in the PI3K-Akt signaling pathway, with the identification of five hub genes (JUN, EGFR, ESR1, RELA, and AKT1). TRP extracts significantly inhibited cell metabolic activity, migration, invasion, and proliferation and promoted cell apoptosis in OSCC cells. Notably, the application of TRP extracts exhibited the capacity to downregulate mRNA and phosphorylated protein levels of AKT1 and ESR1, while concomitantly inducing upregulation of mRNA and phosphorylated protein levels in the remaining three hub genes (EGFR, JUN, and RELA). The functional rescue assay demonstrated that the co-administration of TRP and the PI3K activator 740Y-P effectively reversed the impact of TRP on the phenotypes of OSCC cells. Conversely, the combination of TRP and the PI3K inhibitor LY294002 further enhanced the effect of TRP on the phenotypes of OSCC cells. Remarkably, treatment with TRP in zebrafish xenograft models demonstrated a significant reduction in both tumor growth and metastatic spread. ConclusionsTriphala exerted significant inhibitory effects on cell metabolic activity, migration, invasion, and proliferation in OSCC cell lines, accompanied by the induction of apoptosis, which was mediated through the inactivation of the PI3K/Akt pathway.

Plumbagin Induces Reactive Oxygen Species and Endoplasmic Reticulum Stress-related Cell Apoptosis in Human Oral Squamous Cell Carcinoma.

Oral squamous cell carcinoma (OSCC), a major malignancy in Taiwan, is an invasive epithelial neoplasm resulting in a low survival rate. Current treatments do not prevent OSCC progression, and antitumor therapies should be improved. Plumbagin, a natural compound extracted from Plumbago zeylanica L., appears to have antitumor effects in various tumors. The antitumor mechanism of plumbagin in OSCC is still unclear. This study investigated the molecular mechanism through which plumbagin induces apoptosis. To investigate the antiproliferative and pro-apoptotic effects of Plumbagin on OSCC cells and explore its underlying mechanism, cell counting kit-8, cell cycle analysis, and annexin V/PI assay were conducted. The functions of plumbagin on endoplasmic reticulum (ER) stress, reactive oxygen species (ROS) production, and mitochondrial membrane potential (MMP) deficiency were analyzed using flow cytometric analysis. Plumbagin-induced apoptosis-associated proteins were detected using western blotting. Plumbagin induced apoptosis in OSCC cells by suppressing tumor cell proliferation through ROS production, ER stress, mitochondrial dysfunction, and caspases activation. Plumbagin is a promising antitumor candidate targeting human OSCC.

Imatinib inhibits oral squamous cell carcinoma by suppressing the PI3K/AKT/mTOR signaling pathway.

Oral squamous cell carcinoma (OSCC) is a prevalent oral and maxillofacial cancer with high mortality as OSCC cells readily invade tissues and metastasize to cervical lymph nodes. Although imatinib exhibits potential anticancer and remarkable clinical activities that therapeutically affect several cancer types, its specific impact on OSCC has yet to be fully explored. Therefore, this study investigated the potential anticancer effect of imatinib on OSCC cells and the underlying mechanisms. The Cell Counting Kit-8 was used to determine the impact of imatinib on cell viability. Then, morphological cell proliferation analysis was conducted to examine how imatinib impacted OSCC cell growth. Moreover, OSCC cell migration was determined through wound-healing assays, and colony formation abilities were investigated through the soft agar assay. Lastly, the effect of imatinib on OSCC cell apoptosis was verified with flow cytometry, and its inhibitory mechanism was confirmed through Western blot. Our results demonstrate that imatinib effectively inhibited OSCC cell proliferation and significantly curtailed OSCC cell viability in a time- and concentration-dependent manner. Furthermore, imatinib suppressed migration and colony formation while promoting OSCC cell apoptosis by enhancing p53, Bax, and PARP expression levels and reducing Bcl-2 expression. Imatinib also inhibited the PI3K/AKT/mTOR signaling pathway and induced OSCC cell apoptosis, demonstrating the potential of imatinib as a treatment for oral cancer.

Bromodomain-containing protein 4 inhibition improves the efficacy of cisplatin and radiotherapy in oral squamous cell carcinoma by suppressing programmed cell death-ligand 1 expression.

The bromodomain-containing protein 4 (BRD4) is highly expressed in oral squamous cell carcinoma (OSCC) and plays a crucial role in tumour progression. However, the impact of BRD4 on the efficacy of chemotherapy and radiotherapy by regulating the expression of programmed cell death-ligand 1 (PD-L1) in OSCC remains unclear. In this study, we found that the BRD4 inhibitor JQ1 effectively enhanced the inhibitory effects of cisplatin and radiotherapy on cell proliferation and promoted the apoptosis of OSCC cells by cisplatin and radiotherapy. Furthermore, treatment with JQ1 reversed the increase of the expression of PD-L1 by cisplatin and radiotherapy, whereas the overexpression of PD-L1 partially countered the beneficial effects of JQ1 on the anticancer efficacy of cisplatin and radiotherapy. These results demonstrate that the inhibition of BRD4 improves the anticancer effect of chemotherapy and radiotherapy by suppressing the expression of PD-L1 in OSCC, suggesting that targeting BRD4 could be a promising therapeutic approach for chemo/radioresistant OSCC.

Antitumor effect of toosendanin on oral squamous cell carcinoma via suppression of p-STAT3

BackgroundToosendanin (TSN) exhibits potent antitumor activity against various tumor cell lines. However, its efficacy against oral squamous cell carcinoma (OSCC) remains unknown. Here, we investigated the effects of TSN on OSCC cells in vitro and verified them in vivo using a patient-derived xenograft (PDX) model.MethodsThe effect of TSN on OSCC cells was investigated by cytotoxicity assays and flow cytometry. The expression of proteins was detected by western blotting. An OSCC PDX model was constructed to further investigate the role of TSN in regulating the function of OSCC.ResultsThe cell viability of CAL27 and HN6 cells decreased as the concentration of TSN increased within the experimental range. Compared with controls, TSN at lower doses inhibited cell proliferation and induced apoptosis through S-phase cell cycle arrest. TSN inhibited OSCC cell proliferation by downregulating the STAT3 pathway through the inhibition of STAT3 phosphorylation. After successful construction of the OSCC PDX model with high pathological homology to the primary tumor and treatment with an intraperitoneal injection of TSN, we showed that TSN significantly reduced the tumor size of the PDX model mice without obvious toxicity.ConclusionsBoth in vitro and in vivo, TSN significantly inhibits the proliferation and promoted apoptosis of OSCC cells. Furthermore, TSN demonstrates potent inhibition of STAT3 phosphorylation, indicating its potential as a promising therapeutic agent for OSCC. Therefore, TSN holds great promise as a viable drug candidate for the treatment of OSCC.

Gastrodin overcomes chemoresistance via inhibiting Skp2-mediated glycolysis

Aerobic glycolysis, a typical phenotype in human tumors, is associated with tumor progression and chemotherapy resistance. The present study demonstrated that cisplatin-resistant oral squamous cell carcinoma (OSCC) cells exerted a stronger glycolysis ability, which was associated with hexokinase 2 (HK2) overexpression. Additionally, the tumor growth of OSCC cells was delayed in vivo and the glycolysis was notably decreased following HK2 knockdown. The natural compound screening revealed that gastrodin could be an effective candidate for OSCC therapy since it inhibited HK2-mediated glucose metabolism and promoted endogenous OSCC cell apoptosis. Furthermore, gastrodin could bind to protein kinase B (Akt) and suppress its activity, thus downregulating HK2 at the transcriptional level. Additionally, S-phase kinase-associated protein 2 (Skp2) was highly expressed in OSCC cells, while K63-linked ubiquitination of Akt was inhibited in Skp2-depleted cisplatin-resistant OSCC cells. Gastrodin could also inhibit the cisplatin resistance of OSCC cells in vivo, particularly when combined with the Skp2 inhibitor, SZL P1-41. Overall, the aforementioned finding suggested that targeting the Skp2-Akt axis could be a potential therapeutic strategy for treating OSCC and overcoming chemoresistance.

Simvastatin inhibits proliferation and promotes apoptosis of oral squamous cell carcinoma through KLF2 signal

ObjectivesThis study aimed to explore the role and specific mechanism of the cholesterol-lowering drug simvastatin in inhibiting oral squamous cell carcinoma (OSCC). MethodsThe proliferation, apoptosis, and migration levels of OSCC cells were detected by CCK8, quantitative real-time polymerase chain reaction, Western blot, colony formation, TdT-mediated dUTP Nick-End Labeling assay, and wound healing assay. The inhibitory effect of simvastatin in vivo was detected by a mouse xenograft tumor model. Immunohistochemistry and immunofluorescence staining were used to assess the KLF2 and β-catenin expressions in cells and tissues. ResultsKLF2 expression in OSCC cells and tissues was downregulated. The addition of KLF2 inducer, GGTI298, inhibited the proliferation and migration of OSCC cells. Simvastatin played a role in inhibiting the proliferation and promoting the apoptosis of OSCC cells. Moreover, it inhibited β-catenin expression and promoted KLF2 expression in OSCC cells. KLF2 siRNA reversed the effect of simvastatin on the proliferation and apoptosis of OSCC cells. ConclusionsKLF2, as a tumor suppressor gene, may be an important marker for diagnosing and treating OSCC. Simvastatin inhibits the progression of OSCC by regulating the KLF2 signal.

Cytotoxic, anti-proliferative, and apoptotic evaluation of Ramalina sinensis (Ascomycota, Lecanoromycetes), lichenized fungus on oral squamous cell carcinoma cell line; in-vitro study

BackgroundScientists and medical professionals are actively striving to improve the efficacy of treatment methods for oral squamous cell carcinoma (OSCC), the most frequently occurring cancer within the oral cavity, by exploring the potential of natural products. The active pharmacological compounds found in lichenized fungi have shown potential for aiding in cancer treatment. Recent research aims to evaluate the impact of the lichenized fungus Ramalina sinensis (R. sinensis) on the cell viability and apoptosis of OSCC cell lines, considering the anti-inflammatory and anti-cancer capabilities of lichens.MethodsRamalina sinensis (Ascomycota, Lecanoromycetes) was selected for investigation of its effects on a human oral squamous cell carcinoma cell line. Acetone and methanol extracts of R. sinensis on an OSCC cell line (KB cell line, NCBI Code: C152) were investigated. Viability was assessed by MTT assay analysis, and apoptotic cells were measured using flow cytometry analysis. Scratch assay was used to assess cell migration. The chemical composition and metabolic profiling of R. sinensis were investigated.ResultsThe growth and multiplication of KB cells were observed to undergo a gradual but remarkable inhibition when exposed to various concentrations. Specifically, concentrations of 6.25, 12.5, 25, 50, 100, and 200 μg/mL exhibited a significant suppressive effect on the proliferation of KB cells. The inhibition of cell proliferation exhibited a statistically significant difference between the extracts obtained from acetone and methanol. Flow cytometry results show an increase in apoptosis of OSCC cells by acetone extract. R. sinensis exerted a concentration-dependent inhibitory effect on the migration of OSCC cells. The chemical composition of R. sinensis was investigated using liquid chromatography positive ion electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS), and 33 compounds in the acetone and methanol extracts of R. sinensis were detected.ConclusionThe findings provide evidence supporting the beneficial effects of R. sinensis extract on inducing apoptosis in OSCC cells and exerting anti-cancer properties.

CircNFATC3 facilitated the progression of oral squamous cell carcinoma via the miR-520h/LDHA axis.

The aim of this study was to verify the effects of circular RNA nuclear factor of activated T-cells, cytoplasmic 3 (circNFATC3), in oral squamous cell carcinoma (OSCC) development. The levels of circNFATC3, microRNA-520h (miR-520h), and lactate dehydrogenase A (LDHA) were measured by qRT-PCR and western blot analysis. The cellular functions were assessed by using commercial kits, MTT assay, EdU assay, flow cytometry analysis, and transwell assay. The interactions between miR-520h and circNFATC3 or LDHA were confirmed by dual-luciferase reporter assay. Finally, the mice test was enforced to evaluate the character of circNFATC3. We observed that the contents of circNFATC3 and LDHA were upregulated and miR-520h levels were downregulated in OSCC tissues compared with those in paracancerous tissues. For functional analysis, circNFATC3 knockdown repressed the cell glycolysis metabolism, cell proliferation, migration, and invasion, although it improved cell apoptosis in OSCC cells. LDHA could regulate the development of OSCC. circNFATC3 acted as a miR-520h sponge to modulate LDHA expression. In addition, the absence of circNFATC3 subdued tumor growth in vivo. In conclusion, circNFATC3 promoted the advancement of OSCC by adjusting the miR-520h/LDHA axis.

Hispolon induces apoptosis in oral squamous cell carcinoma cells through JNK/HO-1 pathway activation.

Oral squamous cell carcinoma (OSCC) has a high recurrence rate and poor prognosis. Hispolon, a polyphenolic compound with antiviral, antioxidant, and anticancer activities, is a potential chemotherapy agent. However, few studies have investigated the anti-cancer mechanism of hispolon in oral cancer. This present study used the cell viability assay, clonogenic assay, fluorescent nuclear staining, and flow cytometry assay to analyse the apoptosis-inducing effects of hispolon in OSCC cells. After hispolon treatment, the apoptotic initiators, cleaved caspase-3, -8, and - 9, were upregulated, whereas the cellular inhibitor of apoptosis protein-1 (cIAP1) was downregulated. Furthermore, a proteome profile analysis using a human apoptosis array revealed the overexpression of heme oxygenase-1 (HO-1) by hispolon, which was determined to be involved in caspase-dependent apoptosis. Moreover, cotreatment with hispolon and mitogen-activated protein kinase (MAPK) inhibitors revealed that hispolon induces apoptosis in OSCC cells through activation of the c-Jun N-terminal kinase (JNK) pathway and not the extracellular signal-regulated kinase (ERK) or p38 pathway. These findings indicate that hispolon may exert an anticancer effect on oral cancer cells by upregulating HO-1 and inducing caspase-dependent apoptosis by activating the JNK pathway.