Isoliquiritigenin Inhibits Oral Squamous Cell Carcinoma and Overcomes Chemoresistance by Destruction of Survivin.

The oncoprotein survivin plays a pivotal role in controlling cell division and preventing apoptosis by inhibiting caspase activation. Its significant contribution to tumorigenesis and therapeutic resistance has been well established. Isoliquiritigenin (ISL), a natural compound, has been recognized for its powerful inhibitory effects against various tumors. However, whether ISL exerts regulatory effects on survivin and its underlying mechanism in oral squamous cell carcinoma (OSCC) remains unclear. Here, we found that ISL inhibited the viability and colony formation of OSCC, and promoted their apoptosis. The immunoblotting data showed that ISL treatment significantly decreased survivin expression. Mechanistically, ISL suppressed survivin phosphorylation on Thr34 by deregulating Akt-Wee1-CDK1 signaling, which facilitated survivin for ubiquitination degradation. ISL inhibited CAL27 tumor growth and decreased p-Akt and survivin expression in vivo. Meanwhile, survivin overexpression caused cisplatin resistance of OSCC cells. ISL alone or combined with cisplatin overcame chemoresistance in OSCC cells. Overall, our results revealed that ISL exerted potent inhibitory effects via inducing Akt-dependent survivin ubiquitination in OSCC cells.

Network-Based Method to Investigate the Promoted Cell Apoptosis Mechanisms of Oridonin in OSCC through the RNA-Transcriptome.

The morbidity of oral cancer is high in the world. Oridonin is a traditional Chinese medicine that can effectively inhibit oral squamous cell carcinoma (OSCC) growth, but its mechanism remains unclear. Our previous data showed that oridonin inhibited CAL-27 cell proliferation and promoted apoptosis. Herein, we explored the mechanism and target of oridonin in human OSCC through RNA sequencing and integration of multiple bioinformatics analysis strategies. Differences in gene expression can be analyzed with RNA sequencing. Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), gene set enrichment analysis (GSEA), Disease Ontology (DO), and other enrichment analyses were used to evaluate differentially expressed genes (DEGs). Protein-protein interaction (PPI) networks were built via the STRING database. It was found that tumor necrosis factor (TNF) signaling pathway, cytokine-cytokine receptor interaction, and nuclear factor-kappa B (NF-kappaB) signaling pathway were associated with the therapeutic effects of oridonin in OSCC. Three key genes (BIRC3, TNFSF10, and BCL6) were found to associate with cell apoptosis in OSCC cells treated with oridonin. Quantitative PCR assays verified the expression of apoptosis-related DEGs: TNFSF10, BIRC3, AIFM2, BCL6, BCL2L2, and Bax. Western blots were employed for verifying proteins expression associated with DEGs: cleaved caspase 3, Bax, Bcl-w, anti-cIAP2, and anti-TRAIL. In conclusion, our findings reveal the molecular pathways and targets by which oridonin can treat and induce cytotoxic effects in OSCC: by affecting the signaling including TNF, NF-κB, and cytokine-cytokine receptor interaction and by regulating the key gene BIRC3, TNFSF10, and BCL6. It should be noted that further clinical trial validation is very necessary. Combined with current research trends, our existing research may provide innovative research drugs for the treatment of OSCC.

Plumbagin induces the apoptosis of drug-resistant oral cancer in vitro and in vivo through ROS-mediated endoplasmic reticulum stress and mitochondrial dysfunction.

BACKGROUND: Oral cancer is one of the leading causes of cancer-related deaths worldwide. Chemotherapy is widely used in the treatment of oral cancer, but its clinical efficacy is limited by drug resistance. Hence, novel compounds capable of overcoming drug-resistance are urgently needed. PURPOSE: Plumbagin (PG), a natural compound isolated from Plumbago zeylanica L, has been used to treat various cancers. In this study, we investigated the anticancer effects of PG on drug-resistant oral cancer (CR-SAS) cells, as well as the underlying mechanism. METHODS: MTT assays were used to evaluate the effect of PG on the viability of CR-SAS cells. Apoptosis and reactive oxygen species (ROS) production by the cells were determined using flow cytometry. Protein expression levels were detected by western blotting. RESULTS: The results show that PG reduces the viability and causes the apoptosis of CR-SAS cells. PG is able to induce intracellular and mitochondrial ROS generation that leads to mitochondrial dysfunction. Furthermore, endoplasmic reticulum (ER) stress was triggered in PG-treated CR-SAS cells. The inhibition of ROS using N-acetylcysteine (NAC) abrogated the PG-induced ER stress and apoptosis, as well as the reduction in cell viability. Meanwhile, similar results were observed both in zebrafish and in murine models of drug-resistant oral cancer. CONCLUSION: Our results indicate that PG induces the apoptosis of CR-SAS cells via the ROS-mediated ER stress pathway and mitochondrial dysfunction. It will be interesting to develop the natural compound PG for the treatment of drug-resistant oral cancer.

ROS-Induced DNA-Damage and Autophagy in Oral Squamous Cell Carcinoma by Usnea barbata Oil Extract-An In Vitro Study.

Oxidative stress is associated with aging, cancers, and numerous metabolic and chronic disorders, and phenolic compounds are well known for their health-promoting role due to their free-radical scavenging activity. These phytochemicals could also exhibit pro-oxidant effects. Due to its bioactive phenolic secondary metabolites, Usnea barbata (L.) Weber ex. F.H. Wigg (U. barbata) displays anticancer and antioxidant activities and has been used as a phytomedicine for thousands of years. The present work aims to analyze the properties of U. barbata extract in canola oil (UBO). The UBO cytotoxicity on oral squamous cell carcinoma (OSCC) CLS-354 cell line and blood cell cultures was explored through complex flow cytometry analyses regarding apoptosis, reactive oxygen species (ROS) levels, the enzymatic activity of caspase 3/7, cell cycle, nuclear shrinkage (NS), autophagy (A), and synthesis of deoxyribonucleic acid (DNA). All these studies were concomitantly performed on canola oil (CNO) to evidence the interaction of lichen metabolites with the constituents of this green solvent used for extraction. The obtained data evidenced that UBO inhibited CLS-354 oral cancer cell proliferation through ROS generation (316.67 × 104), determining higher levels of nuclear shrinkage (40.12%), cell cycle arrest in G0/G1 (92.51%; G0 is the differentiation phase, while during G1 phase occurs preparation for cell division), DNA fragmentation (2.97%), and autophagy (62.98%) than in blood cells. At a substantially higher ROS level in blood cells (5250.00 × 104), the processes that lead to cell death-NS (30.05%), cell cycle arrest in G0/G1 (86.30%), DNA fragmentation (0.72%), and autophagy (39.37%)-are considerably lower than in CLS-354 oral cancer cells. Our work reveals the ROS-mediated anticancer potential of UBO through DNA damage and autophagy. Moreover, the present study suggests that UBO pharmacological potential could result from the synergism between lichen secondary metabolites and canola oil phytoconstituents.

San-Zhong-Kui-Jian-Tang Exerts Antitumor Effects Associated With Decreased Cell Proliferation and Metastasis by Targeting ERK and the Epithelial-Mesenchymal Transition Pathway in Oral Cavity Squamous Cell Carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is an aggressive cancer whose 5-year survival rate remains poor. San-Zhong-Kui-Jian-Tang (SZKJT), a Chinese herbal formula, has long been used in clinical practice as adjuvant therapy in cancers. However, its therapeutic effects and molecular mechanisms in OSCC remain unclear. METHODS: We investigated the potential therapeutic effects and molecular mechanism of SZKJT in OSCC in tumor cell lines and in tumor xenograft mice and evaluated combined SZKJT and cisplatin treatment efficacy. In vitro-cultured OSCC cells were administered SZKJT at different doses or SZKJT plus cisplatin, and cell proliferation, colony formation assays, and cell cycle analysis were used to assess the effects on cancer cell proliferation and apoptosis. We also analyzed the effects of SZKJT on oral cancer cell line migration, the regulation of mitogen-activated protein kinase (MAPK) signaling, and epithelial-mesenchymal transition (EMT)-associated genes. The antitumor effects of SZKJT plus cisplatin were also tested in vivo using a tumor-bearing NOD/SCID mice model. RESULTS: The results showed that SZKJT effectively inhibited OSCC cell proliferation, induced cell cycle S phase arrest, and induced cell apoptosis. SZKJT also inhibited cell migration by modulating the MAPK signaling and epithelial-mesenchymal transition (EMT) pathway. Further exploration suggested that SZKJT affects OSCC by modulating ERK pathway; downregulating vimentin, fibronectin, and Oct-4; and upregulating E-cadherin. In vivo, SZKJT significantly inhibited tumor growth, and SZKJT and cisplatin exerted synergistic antitumor effects in model animals. CONCLUSIONS: SZKJT exerts antitumor effects in OSCC cells. Additionally, SZKJT and cisplatin exhibit synergy in OSCC treatment. These findings support the clinical usage of Chinese herbal formulas as adjuvant therapy with chemotherapy in cancer treatment.

FOXD1-mTOR Signaling Pathway on Oral Squamous Cell Carcinoma and Its Inhibition by Rosemary Extract (Invitro-Study).

BACKGROUND: FOXD1 expression in oral squamous cell carcinoma remains uncovered. The aim was to detect the anticancer effect of Rosemary Extract RE through the evaluation of FOXD1 gene expression in (OSCC) by quantitative PCR. METHODS: OSCC cell line was served as a control group. Moreover, the OSCC cell line (SCC-15) was treated with RE (OSCC/ RE group) at 24, 48, and 72 hs time intervals. We assessed the antioxidant activity of RE by evaluation of lipid peroxidation (MDA) and superoxide dismutase (SOD) levels. The cytotoxic effects of RE were examined by MTT assay. mTOR and LC3 I/II autophagy protein markers were assessed by western blot. Apoptosis activity was assessed. RESULTS: The study results were statistically assessed. Intergroup comparisons were analyzed, whereas intragroup comparisons were conducted utilizing one-way repeated measures ANOVA, followed by multiple pairwise paired t-tests with Bonferroni correction revealed a significant increase of FOXD1 gene expression in the control OSCC group in comparison to the OSCC/RE group (p-value <0.001). A significant decrease of mTOR/LC3I/II proteins expression in the OSCC/RE group compared to the control OSCC group (p-value <0.001). CONCLUSION: FOXD1 can be considred a diagnostic biomarker for OSCC. RE inhibits autophagy of oral human cancer cells via mTOR/LC3I/II-dependent pathways and decrease caspase -3 apoptotic level.

Gambogic Acid Induces HO-1 Expression and Cell Apoptosis through p38 Signaling in Oral Squamous Cell Carcinoma.

Gambogic acid (GA), a natural and bioactive compound from the gamboge resin, has been reported to exhibit many oncostatic activities against several types of malignancies. However, its effects on the progression of oral squamous cell carcinoma (OSCC) remain largely unexplored. To fill this gap, we investigated the anticancer role of GA and molecular mechanisms underlying GA's actions in combating oral cancer. We found that GA negatively regulated the viability of OSCC cells, involving induction of the sub-G1 phase and cell apoptosis. In addition, a specific signature of apoptotic proteome, such as upregulation of heme oxygenase-1 (HO-1) and activation of caspase cascades, was identified in GA-treated OSCC. Moreover, such induction of HO-1 expression and caspase cleavage by GA was significantly diminished through the pharmacological inhibition of p38 kinase. In conclusion, these results demonstrate that GA promotes cell apoptosis in OSCC, accompanied with the activation of a p38-dependent apoptotic pathway. Our findings provide potential avenues for the use of GA with high safety and therapeutic implications in restraining oral cancer.

The Hydrolytic Peptides of Soybean Protein Induce Cell Cycle Arrest and Apoptosis on Human Oral Cancer Cell Line HSC-3.

Protein hydrolysates from various sources, including tuna cooking juice, soy protein isolate, sodium caseinate, wheat gluten and skin gelatin from porcine, tilapia, halibut and milkfish were analyzed to screen their antiproliferative activities against the human oral squamous carcinoma cell line, HSC-3. The soy protein isolate was selected for further investigations based on its hydrolysates with bromelain (SB) and thermolysin (ST), showing the greatest inhibition of cell growth. The SB and ST hydrolysates showed antiproliferative activities up to 35.45-76.39% against HSC-3 cells at 72 h, and their IC50 values were 0.74 and 0.60 mg/mL, respectively. SB and ST induced cell cycle arrest in the S phase through a pathway independent of p21 and p27 protein expression. Further, ST induced the apoptosis of HSC-3 cells by downregulating expression of Bcl-2, PARP, caspase 3 and caspase 9, but an upregulating expression of p53 and cleaved caspase 3. Unlike ST, SB may induce necrosis on HSC-3 cells. Thus, soybean hydrolysates may be a good source for providing antiproliferative peptides against HSC-3, while SB and ST may have the potential to be developed as functional foods.

Liquiritigenin exerts the anti-cancer role in oral cancer via inducing autophagy-related apoptosis through PI3K/AKT/mTOR pathway inhibition in vitro and in vivo.

Operative treatment on oral cancer greatly damages the chewing and language function of the patient, we aim to find better solution with fewer side effects. The anti-tumor effects of Liquiritigenin (LQ) have been explored in kinds of cancers, but not in oral cancer. In this study, our purpose is to reveal the effects of LQ on oral cancer and the associated mechanism.Cell proliferation was examined through 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 5-Ethynyl-2'- deoxyuridine (EDU) staining. Cell apoptosis in cells and tissues were assessed by flow cytometry and terminal dexynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, respectively. Expressions of AKT and light chain 3 (LC3) were detected through Immunofluorescence. In addition, xenograft model was established by injecting the CAL-27 cells (2 × 106) subcutaneously into the right flanks of mice. Expression of Ki67 and Beclin1 in tissues was valued by Immunohistochemistry (IHC).We found that cell viability of CAL-27 and SCC-9 was effectively inhibited by LQ. Besides, obvious cell apoptosis and cell autophagy were induced by LQ. In addition, PI3K/AKT/mTOR pathway was sharply inactivated by LQ in oral cancer cells. Corresponding in vivo experiments demonstrated that tumor growth was largely restricted, cell apoptosis was augmented and autophagy was enhanced by LQ. What is more, phosphorylation of AKT in tumor tissues could also be inhibited by LQ. LQ inhibited the progression of oral cancer through inducing autophagy-associated apoptosis via PI3K/AKT/mTOR pathway inhibition, revealing a new possible scheme for the treatment of oral cancer.

Combinatorial treatment with Gefitinib and Bay11-7085 sensitizes primary Gefitinib-resistant OSCC cells by influencing the EGFR- NFκB signaling axis.

EGFR-targeted therapies are reported to yield modest effect in OSCC. Activation of NFκB signaling is considered as molecular driver of EGFR inhibitor resistance in various cancers. In this scenario, present study focused on the molecular crosstalk between EGFR and NFκB signaling pathways and its therapeutic importance in OSCC. The EGFR- NFκB p65 co-expressed human OSCC cell lines UPCI:SCC066, UPCI:SCC040 and UM-SCC083B were used for in vitro studies. Recombinant human EGF, siRNAs, Western blot and qRT-PCR were used to dissect the molecular crosstalk between EGFR-NFκB signaling pathways in OSCCs. The effect of NFκB p65 knockdown on cancer hallmarks was studied by respective functional assays and RNA-Seq analysis was performed to identify the differentially expressed genes upon NFκB p65 knockdown. Gefitinib and Bay 11-7085 combination treatment was done to study the chemotherapeutic potential of EGFR- NFκB axis. Significant positive correlation between EGFR and NFκB p65 expression was observed in Head and Neck TCGA data set. EGFR induction or knockdown respectively stimulate or impair the NFκB signaling in EGFR- NFκB p65 co-expressed OSCC cell lines. NFκB p65 knockdown causes apoptosis and suppresses the viability, colony formation, migration, invasion, and spheroid formation. Using RNA-seq analysis, we identified PIK3CD as the NFκB target gene, which is commonly involved in these functions. Gefitinib and Bay 11-7085 combination treatment was found to be useful in chemosensitizing the Gefitinib-resistant OSCC cells by capitulating the EGFR- NFκB signaling axis. Combination treatment using Gefitinib and Bay 11-7085 enhanced the apoptosis and reduced cell viability and colony formation in a synergistic way. Our data demonstrated that EGFR-NFκB signaling axis plays a key role in the pathogenesis of OSCCs. Therefore, simultaneous therapeutic intervention of these pathways may be a good alternative approach for the management of OSCCs.

Utilizing feline oral squamous cell carcinoma patients to develop NQO1-targeted therapy.

Developing effective therapies for the treatment of advanced head-and-neck squamous cell carcinoma (HNSCC) remains a major challenge, and there is a limited landscape of effective targeted therapies on the horizon. NAD(P)H:quinone oxidoreductase 1 (NQO1) is a 2-electron reductase that is overexpressed in HNSCC and presents as a promising target for the treatment of HNSCC. Current NQO1-targeted drugs are hindered by their poor oxidative tolerability in human patients, underscoring a need for better preclinical screening for oxidative toxicities for NQO1-bioactivated small molecules. Herein, we describe our work to include felines and feline oral squamous cell carcinoma (FOSCC) patients in the preclinical assessment process to prioritize lead compounds with increased tolerability and efficacy prior to full human translation. Specifically, our data demonstrate that IB-DNQ, an NQO1-targeted small molecule, is well-tolerated in FOSCC patients and shows promising initial efficacy against FOSCC tumors in proof-of-concept single agent and radiotherapy combination cohorts. Furthermore, FOSCC tumors are amenable to evaluating a variety of target-inducible couplet hypotheses, evidenced herein with modulation of NQO1 levels with palliative radiotherapy. The use of felines and their naturally-occurring tumors provide an intriguing, often underutilized tool for preclinical drug development for NQO1-targeted approaches and has broader applications for the evaluation of other anticancer strategies.

Dioscin inhibits SCC15 cell proliferation via the RASSF1A/MST2/YAP axis.

Dioscin, an extract from traditional Chinese herbal plants, displays various biological and pharmacological effects on tumors, including inhibition of cell proliferation and induction of DNA damage. However, the effects of dioscin on oral squamous cell carcinoma (OSCC) cells are not completely understood. The present study aimed to evaluate the impact of dioscin on OSCC cell proliferation. Cell Counting Kit­8 and 5­ethynyl­2'­deoxyuridine incorporation assays were performed to assess cell proliferation. Flow cytometry was conducted to detect alterations in the cell cycle and cell apoptosis. Western blotting and coimmunoprecipitation were performed to determine protein expression levels. In SCC15 cells, dioscin treatment significantly induced cell cycle arrest, increased apoptosis and inhibited proliferation compared with the control group. Mechanistically, the tumor suppressor protein Ras association domain­containing protein 1A (RASSF1A) was activated and oncoprotein yes­associated protein (YAP) was phosphorylated by dioscin. Furthermore, YAP overexpression and knockdown reduced and enhanced the inhibitory effects of dioscin on SCC15 cells, respectively. In summary, the results demonstrated that, compared with the control group, dioscin upregulated RASSF1A expression in OSCC cells, which resulted in YAP phosphorylation, thus weakening its transcriptional coactivation function, enhancing cell cycle arrest and apoptosis, and inhibiting cell proliferation. The present study indicated that dioscin may serve as a therapeutic agent for OSCC.

Role of hyaluronan mediated motility receptor gene in oral squamous cell carcinoma and clinical prognosis. / é€æ˜Žè´¨é ¸ä»‹å¯¼è¿åŠ¨å› å­å—ä½“åŸºå› åœ¨å£è ”é³žçŠ¶ç»†èƒžç™Œä¸­çš„ä½œç”¨åŠå ¶ä¸´åºŠé¢„åŽ.

OBJECTIVES: To screen genes related to the prognosis of oral squamous cell carcinoma (OSCC), and to explore its role and mechanism in the occurrence and development of OSCC. METHODS: The data and the biological information in 330 OSCC tumor samples with head and neck squamous cell carcinoma (HNSCC) (OSCC group) and 37 normal samples (normal sample group) were screened and included, which came from the cancer genome atlas (TCGA) database. The differentially expressed genes were screened out by biological information analysis between the 2 groups. Furthermore, according to the tumor T grade (T1+T2 group: 114 cases, T3+T4 group: 216 cases), metastasis (positive group: 163 cases, negative group: 167 cases) and pathological grade (G1+G2 group: 244 cases, G3 +G4 group: 86 cases), the samples were divided into different groups respectively, and the differential genes were obtained separately, then the intersections of the differential expressed genes related to the prognosis of OSCC were screened. The different gene with the largest different multiples [hyaluronan mediated motility receptor (HMMR)] was selected for the next step in order to explore the relationship between HMMR and clinical grading (Stage I+II group: 69 cases, Stage III +IV group: 261 cases), as well as the relationship between T grade, metastasis and pathological grade. According to the median value of HMMR expression, the samples were divided into a high expression group and a low expression group (high expression group: 165 cases, low expression group: 165 cases); Kaplan-Meier survival analysis was used to explore the relationship between HMMR expression and prognosis. Tumor tissue specimens and corresponding normal oral mucosal tissue specimens in 50 OSCC patients, who underwent surgery in the First Affiliated Hospital of Hunan University of Traditional Chinese Medicine from January 2014 to January 2016, were collected. Real-time RT-PCR and Western blotting and immunohistochemistry were used to verify the bioinformatics analysis results. Kaplan-Meier survival analysis was used to examine the relationship between the positive and negative expression of HMMR immunohistochemical staining (positive group: 32 cases, negative group: 18 cases) and prognostic related factors, and Cox regression analysis model was used to explore the prognostic risk factors of OSCC. The cell proliferation experiment and the cell scratch experiment were used to evaluate the effect of down-regulation of HMMR on the proliferation and migration of OSCC cells. RESULTS: HMMR was highly expressed in OSCC tissues. Compared with the low HMMR expression group, the prognostic related factors in the HMMR high expression group was significantly lower, with significant difference (all P<0.05); the high expression of HMMR was significantly related with the T grade (RR=1.33, P<0.05), lymphonodus metastasis (RR=1.74, P<0.05), the clinical stage (RR=1.49, P<0.05), and it was an independent prognostic risk factor for OSCC (RR=1.45, P<0.05). Down-regulation of HMMR can inhibit the proliferation and migration of OSCC cells, with significant difference (P<0.05 or P<0.01). CONCLUSIONS: HMMR, as a proto-oncogene of OSCC, can promote the occurrence and development of OSCC, and it may be used as a potential early diagnostic marker and a new target for therapy.

Therapeutic applications of herbal/synthetic/bio-drug in oral cancer: An update.

Oral cancer, as one of the most prevalent and invasive cancers that invade local tissue, can cause metastasis, and have high mortality. In 2018, around 355,000 worldwide oral cancers occurred and resulted in 177,000 deaths. Estimates for the year 2020 include about 53,260 new cases added to previous year's cases, and the estimated death toll from this cancer in 2020 is about 10,750 deaths more than previous years. Despite recent advances in cancer diagnosis and treatment, unfortunately, 50% of people with cancer cannot be cured. Of course, it should be remembered that the type of treatment used greatly influences patient recovery. There are not many choices when it comes to treating oral cancer. Research efforts focusing on the discovery and evolution of innovative therapeutic approaches for oral cancer are essential. Such traditional methods of treating this type of cancer like surgery and chemotherapy, have evolved dramatically during the past thirty to forty years, but they continue to cause panic among patients due to their side effects. Therefore, it is necessary to study and use drugs that are less risky for the patient as well as to provide solutions to reduce chemotherapy-induced adverse events that prevent many therapeutic risks. As mentioned above, this study examines low-risk therapies such as herbal remedies, biological drugs, and synthetic drugs in the hope that they will be useful to physicians, researchers, and scientists around the world.

Genistein nanoformulation promotes selective apoptosis in oral squamous cell carcinoma through repression of 3PK-EZH2 signalling pathway.

BACKGROUND: Overexpression of polycomb protein contributes to epigenetic repression in oral squamous cell carcinoma (OSCC) ensuing in poor prognosis and aggressive phenotype. Several plant-based compounds could help prevent epigenome alteration and cancer progression, but their low bioavailability limits their therapeutic activity. HYPOTHESIS: In this study, we have synthesized genistein nanoformulation (GLNPs) and evaluated its epigenetic regulation mechanism for selective apoptosis induction in OSCC. METHODS: Lactalbumin was used to prepare nanoformulation of Genistein. The mechanism of epigenetic regulation and selective apoptosis by Genistein loaded nanoparticles was studied in OSCC cell line JHU011 and fibroblast cell line L929 using immunofluorescence, Western blotting and ChIP-qPCR assay. RESULTS: We have found that GLNPs treatment selectively induced apoptosis in OSCC compared to the normal fibroblast cells. This selective effect in OSCC is achieved through enhanced reactive oxygen species (ROS) generation followed by Bax mitochondrial translocation and caspase 3 activation. Further, GLNPs induced withdrawal of epigenetic transcription repression through concurrent downregulation of the polycomb group proteins (PcG) Bmi 1 and EZH2 along with their successive targets, UbH2AK119 and H3K27me3, which have immense therapeutic implications in the treatment of OSCC. Last, we have established that GLNPs regulate EZH2expression through proteasomal mediated degradation and 3PK inhibition; 3PK protein was found physically linked with EZH2 protein and its promoter region (-1107 to -1002). This event indicates that 3PK might play some crucial role in EZH2 expression and epigenetic control of OSCC. Moreover, the formulation showed improved biodistribution, aqueous dispersibility and enhanced biocompatibility In-vivo. CONCLUSIONS: These results provide evidence that GLNPs may withdraw epigenetic transcriptional repression and selectively induce apoptosis in human oral squamous cell carcinoma.

Pathways Related to the Anti-Cancer Effects of Metabolites Derived from Cerrado Biome Native Plants: An Update and Bioinformatics Analysis on Oral Squamous Cell Carcinoma.

BACKGROUND: Oral cancer is a significant health problem worldwide. Oral squamous cell carcinoma (OSCC) is a malignant neoplasm of epithelial cells that mostly affects different anatomical sites in the head and neck and derives from the squamous epithelium or displays similar morphological characteristics. Generally, OSCC is often the end stage of several changes in the stratified squamous epithelium, which begin as epithelial dysplasia and progress by breaking the basement membrane and invading adjacent tissues. Several plant-based drugs with potent anti-cancer effects are considered inexpensive treatments with limited side effects for cancer and other diseases. OBJECTIVE: The aim of this review is to explore whether some Brazilian plant extracts or constituents exhibit anti-tumorigenic activity or have a cytotoxic effect on human oral carcinoma cells. METHODS: Briefly, OSCC and several metabolites derived from Brazilian plants (i.e., flavonoids, vinblastine, irinotecan, etoposide and paclitaxel) were used as keywords to search the literature on PubMed, GenBank and GeneCards. RESULTS: The results showed that these five chemical compounds found in Cerrado Biome plants exhibit anti-neoplastic effects. Evaluating the compounds revealed that they play a main role in the regulation of cell proliferation. CONCLUSION: Preserving and utilising the biodiversity of our planet, especially in unique ecosystems, such as the Cerrado Biome, may prove essential to preserving and promoting human health in modern contexts.

Natural Compounds Modulate Drug Transporter Mediated Oral Cancer Treatment.

Oral cancer (OC) is a serious health problem. Surgery is the best method to treat the disease but might reduce the quality of life of patients. Photodynamic therapy (PDT) may enhance quality of life but with some limitations. Therefore, the development of a new strategy to facilitate PDT effectiveness has become crucial. ATP-binding cassette G2 (ABCG2) is a membrane protein-associated drug resistance and stemness in cancers. Here, we examined whether ABCG2 plays an important role in regulating the treatment efficacy of PDT and whether ABCG2 inhibition by natural compounds can promote the effect of PDT in OC cells. Several head and neck cancer cells were utilized in this study. OECM1 and SAS cells were selected to investigate the relationship between ABCG2 expression and protoporphyrin IX (PpIX) accumulation. Western blot analysis, flow cytometry analysis, and survival probability were performed to determine PDT efficacy and cellular stemness upon treatment of different dietary compounds, including epigallocatechin gallate (EGCG) and curcumin. In this study, we found that ABCG2 expression varied in OC cells. Hypoglycemic culture for SAS cells enhanced ABCG2 expression as higher ABCG2 expression was associated with lower PpIX accumulation and cellular stemness in OC cells. In contrast, suppression of ABCG2 expression by curcumin and tea polyphenol EGCG led to greater PpIX accumulation and enhanced PDT treatment efficiency in OC cells. In conclusion, ABCG2 plays an important role in regulating the effect of PDT. Change in glucose concentration and treatment with natural compounds modulated ABCG2 expression, resulting in altered PDT efficacy for OC cells. These modulations raise a potential new treatment strategy for early-stage OCs.

Novel ANO1 Inhibitor from Mallotus apelta Extract Exerts Anticancer Activity through Downregulation of ANO1.

Anoctamin1 (ANO1), a calcium-activated chloride channel, is frequently overexpressed in several cancers, including human prostate cancer and oral squamous cell carcinomas. ANO1 plays a critical role in tumor growth and maintenance of these cancers. In this study, we have isolated two new compounds (1 and 2) and four known compounds (3-6) from Mallotus apelta. These compounds were evaluated for their inhibitory effects on ANO1 channel activity and their cytotoxic effects on PC-3 prostate cancer cells. Interestingly, compounds 1 and 2 significantly reduced both ANO1 channel activity and cell viability. Electrophysiological study revealed that compound 2 (Ani-D2) is a potent and selective ANO1 inhibitor, with an IC50 value of 2.64 µM. Ani-D2 had minimal effect on cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel activity and intracellular calcium signaling. Notably, Ani-D2 significantly reduced ANO1 protein expression levels and cell viability in an ANO1-dependent manner in PC-3 and oral squamous cell carcinoma CAL-27 cells. In addition, Ani-D2 strongly reduced cell migration and induced activation of caspase-3 and cleavage of PARP in PC-3 and CAL-27 cells. This study revealed that a novel ANO1 inhibitor, Ani-D2, has therapeutic potential for the treatment of several cancers that overexpress ANO1, such as prostate cancer and oral squamous cell carcinoma.

Protection of Bortezomib-induced Neurotoxicity by Antioxidants.

BACKGROUND/AIM: Although chemotherapy agents, such as oxaliplatin, cisplatin, paclitaxel and bortezomib frequently cause severe peripheral neuropathy, very few studies have reported the effective strategy to prevent this side effect. In this study, we first investigated whether these drugs show higher neuropathy compared to a set of 15 other anticancer drugs, and then whether antioxidants, such as sodium ascorbate, N-acetyl-L-cysteine, and vitamin B12 have any protective effect against them. MATERIALS AND METHODS: Rat PC12 cells were induced to differentiate into neuronal cells by repeated overlay of serum-free medium supplemented with nerve growth factor. The cytotoxic levels of anticancer drugs against four human oral squamous cell carcinoma cell lines, three normal oral cells, and undifferentiated and differentiated PC12 cells were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Cells were sorted for apoptotic cells (distributed into subG1 phase) and cells at different stages of cell cycle (G1, S and G2/M). RESULTS: All 19 anticancer drugs showed higher cytotoxicity against PC12 compared to oral normal cells. Among them, bortezomib showed the highest cytotoxicity against both undifferentiated and differentiated PC12 cell and, committed them to undergo apoptosis. Sodium ascorbate and N-acetyl-L-cysteine, but not vitamin B12, completely reversed the cytotoxicity of bortezomib. CONCLUSION: Bortezomib-induced neuropathy might be ameliorated by antioxidants.

EMMPRIN/BASIGIN as a biological modulator of oral cancer and COVID-19 interaction: Novel propositions.

Extracellular matrix metalloproteinase inducer (EMMPRIN), which is also called BASIGIN/CD147, is a cell surface glycoprotein that belongs to the immunoglobulin superfamily and plays a significant role in intercellular recognition in immunology, cellular differentiation and development. Apart from ACE-2, recently EMMPRIN, has been regarded as a target for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) attachment and entry into the host cell. Since one of the routes of entry for the virus is the oral cavity, it becomes imperative to percept oral comorbidities such oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs) in terms of EMMPRIN as a target for SARS-CoV-2. In the present paper, it is proposed that OSCC, by the virtue of upregulation of EMMPRIN expression, increases the susceptibility to coronavirus disease (COVID-19). In turn, COVID-19 in OSCC patients causes exhaustion of EMMPRIN receptor due to binding with 'S' receptor leading to a downregulation of related carcinogenesis events. We proposed that in the ACE-2 depleted situation in OSCC, EMMPRIN receptor might get high jacked by the COVID-19 virus for the entry into the host cells. Apart from the anti-monoclonal antibody, it is recommended to explore the use of grape seed and skin containing mouthwash as an adjunct, which could also have anti EMMPRIN effects in patients with OSCC and OPMDs.