Human Squamous Carcinoma Cell Line Research Articles

Effect of paclitaxel treatment on cellular mechanics and morphology of human oesophageal squamous cell carcinoma in 2D and 3D environments.

During chemotherapy, structural and mechanical changes in malignant cells have been observed in several cancers, including leukaemia and pancreatic and prostate cancer. Such cellular changes may act as physical biomarkers for chemoresistance and cancer recurrence. This study aimed to determine how exposure to paclitaxel affects the intracellular stiffness of human oesophageal cancer of South African origin in vitro. A human oesophageal squamous cell carcinoma cell line WHCO1 was cultured on glass substrates (2D) and in collagen gels (3D) and exposed to paclitaxel for up to 48 h. Cellular morphology and stiffness were assessed with confocal microscopy, visually aided morpho-phenotyping image recognition and mitochondrial particle tracking microrheology at 24 and 48 h. In the 2D environment, the intracellular stiffness was higher for the paclitaxel-treated than for untreated cells at 24 and 48 h. In the 3D environment, the paclitaxel-treated cells were stiffer than the untreated cells at 24 h, but no statistically significant differences in stiffness were observed at 48 h. In 2D, paclitaxel-treated cells were significantly larger at 24 and 48 h and more circular at 24 but not at 48 h than the untreated controls. In 3D, there were no significant morphological differences between treated and untreated cells. The distribution of cell shapes was not significantly different across the different treatment conditions in 2D and 3D environments. Future studies with patient-derived primary cancer cells and prolonged drug exposure will help identify physical cellular biomarkers to detect chemoresistance onset and assess therapy effectiveness in oesophageal cancer patients.

Geniposide inhibits cell proliferation and migration in human oral squamous carcinoma cells via AMPK and JNK signaling pathways

Iridoids are a special class of cyclopentanoid monoterpenes, which exhibit a wide range of biological effects. The present study aimed to investigate the potential effects of three iridoids genipin, geniposide and geniposidic acid on three human oral squamous cell carcinoma (OSCC) cell lines HSC-2, SCC-9 and A253 in addition to studying the possible underlying mechanisms. Cell viability assay revealed that geniposide treatment significantly suppressed the proliferation of all three cancer cell lines. In addition, geniposide induced SCC-9 cell cycle arrest at the G2/M phase (flow cytometry) through downregulation of cyclin-dependent kinase 2 and Cyclin A2 expression (western blot analysis), whilst also inducing cell apoptosis (flow cytometry and acridine orange/ethidium bromide staining) by dissipating the mitochondrial membrane potential (flow cytometry), and upregulating the expression of cleaved caspase-3 and cleaved poly-ADP ribose polymerase (western blot analysis). A wound-healing assay indicated that geniposide impaired SCC-9 cell migration by increasing the expression of E-cadherin (western blot analysis), whilst suppressing the expression of MMP-2 (western blot analysis). Western blot analysis also demonstrated that geniposide induced autophagy in SCC-9 cells by upregulating the expression of Beclin-1 and light chain 3-II. Mechanistically, geniposide activated the 5'-AMP-activated protein kinase signaling pathway and inhibited the JNK signaling pathway in SCC-9 cells (western blot analysis). The present results indicated that geniposide is able to inhibit the proliferation and migration of the tongue squamous carcinoma cell line SCC-9, suggesting a potential strategy for OSCC treatment.

LC/Q-TOF MS and LC/QQQ MS based bioanalysis of a new ferrocene derivative as a potential anticancer lead with promising drug-like characteristics

Pyrazolopyrimidine ring present in various approved drugs is reported to target the tyrosine kinase receptor. A new pyrazolopyrimidine ferrocene derivative, which targets tumor pyruvate kinase M2 showed an impressive antiproliferative profile against human oral squamous cell carcinoma cell line CAL27 assessed using Alamar blue assay. In line with the lead optimization process, the molecule was studied for physicochemical properties where a bioanalytical method has been developed in plasma on liquid chromatography-mass spectrometry and validated following the USFDA bioanalytical method validation guideline. Plasma stability and plasma protein binding potential of the molecule have been evaluated. All the major metabolites of the compound have been identified through in vitro metabolite study employing rat liver microsome, human liver microsome, and human S9 fractions. The in silico toxicity profile of the metabolites was assessed using ProTox II software. Log P, Log D, and pKa of the molecule were found to be 4.5, 5, and 12, respectively. The molecule was found to be quite stable in plasma and have a moderate affinity towards plasma proteins (about 75 % binding). Four major metabolites have been identified and characterized by UHPLCQ-TOF-MS. The metabolites were found to have a moderate safety profile. The validated bioanalytical method and the metabolic pathway will be useful for future clinical studies and to assess the safety profile of the molecule. The finding of this study may also be useful in analyzing the desired drug-like properties through bioanalysis while designing new chemical entities based on metallocenes.

Cytotoxic test of different solvents of soursop (Annona muricata) leaf extract against HSC-3 cell line

Background: Soursop (Annona muricata) leaves have been researched extensively and found to have anticancer properties. The use of soursop as an anticancer treatment is increasingly popular due to its selective cytotoxic activity by acetogenins. The polarity of the extract solvent contributes to the biological activity of the plant, namely cytotoxicity. Purpose: To determine the cytotoxicity of A. muricata leaf extract with ethanol, ethyl acetate and hexane fractions against human oral squamous carcinoma (HSC-3) cell lines. Methods: This experimental laboratory study consisted of twenty four treatment groups tested against the HSC-3 cell line. The ethanol, ethyl acetate and hexane fractions of A. muricata leaves were administered to seven different concentrations, namely 0.3 μg/mL, 3 μg/mL, 25 μg/mL, 50 μg/mL, 100 μg/mL, 150 μg/mL and 300 μg/mL. The control group consisted of three groups: negative control, solvent control and positive control. The percentage of cell viability was calculated by absorbent enzyme-linked immunosorbent assay (ELISA) reader. The cytotoxicity of A. muricata leaf extract against HSC-3 cells was determined by cell counting kit-8 (CCK-8) assay and expressed by IC50 value. The results were analysed using one-way analysis of variance (ANOVA) followed by Tukey’s honestly significant difference (HSD). Results: The results show that the leaf extracts of A. muricata are moderately cytotoxic to HSC-3 cells. The highest cytotoxic activity was found in the ethyl acetate extract with an IC50 value of 76.66 μg/mL – making it the best solvent – then hexane (IC50: 84.14 μg), then ethanol (IC50: 101.32 μg/mL). Statistical analysis using one-way ANOVA and Tukey’s HSD is considered significant p < 0.001. Conclusion: Ethanol, ethyl acetate and hexane fractions of A. muricata leaf extract are moderately cytotoxic, with IC50 values in the range of 21–200 μg/mL.

Dracaena cinnabari Methanolic Extract impairing Migration and inhibiting Growth of Nasopharyngeal Carcinoma Cells through Induction of Intrinsic Apoptotic Pathway In Vitro

The resin of Dracaena cinnabari Balf. f. has demonstrated antiviral, antibacterial, antioxidative, analgesic and anti-inflammatory properties, which presents some proof for its effectiveness in traditional use. Despite the broad health benefits of Dracaena cinnabari, few research has been conducted on its anti-tumour effect. We have previously shown that Dracaena cinnabari Balf. f methanolic extract (DCBME) induces apoptotic cell death in human tongue squamous cell carcinoma cell line and significantly reduces its migration capacity. The anti-tumour potential and mechanism of action of DCBME in Nasopharyngeal Carcinoma (NPC) have not yet been elucidated. In our recent paper, we showed the disruption of mitochondrial membrane potential and the induction of the intrinsic apoptotic pathway through caspase 3/7 activation. In the present study, we aim to investigate the effect of DCBME on proliferation, morphological changes, cell death, cell cycle arrest and cell migration of NPC cells. NPC cells (C666-1 and HK-1) were treated with DCBME and the mechanism underlying its anti-tumour effect was explored by examining cell proliferation, induction of apoptosis and cell migration using MTT assay, phase-contrast and fluorescence microscopy, propidium iodide staining, DNA fragmentation and wound healing assays. DCBME significantly inhibited NPC cell proliferation in a time and dose-dependent manner. It induced marked apoptotic morphological changes, apoptotic DNA laddering and S and/or G2/M-phase cell cycle arrest. DCBME also inhibited the migration of NPC cells. Together with our previously reported anti-tumour effect of DCBME, the findings suggest that DCBME deserves further investigation as a promising anti-tumour agent for human Nasopharyngeal Carcinoma cells therapy.

LB887 Direct effects of zinc in proliferation and migration of human squamous cell carcinoma cell lines in vitro

Zinc is a trace element that requires for more than 2000 transcription factors. Thus, zinc could have functions in development, differentiation, and cell growth of many cell types including cancer cells. Prior studies reported that zinc induced apoptosis in cancer cells, such as glioma, bladder, prostate, breast, and melanoma. Topical application of high concentration zinc containing Mohs paste is effective to shrink skin cancers including squamous cell carcinoma (SCC), breast cancer. However, the evidences of direct effect of zinc in growth and cell migration of cutaneous SCC cells are scarce.

Identification and pharmacological modification of resistance mechanisms to protoporphyrin-mediated photodynamic therapy in human cutaneous squamous cell carcinoma cell lines

BackgroundPhotodynamic therapy (PDT) is clinically approved to treat neoplastic skin diseases such as precursors of cutaneous squamous cell carcinoma (cSCC). In PDT, 5-aminolevulinic acid (5-ALA) drives the selective formation of the endogenous photosensitizer protoporphyrin IX (PpIX). Although 5-ALA PDT is clinically highly effective, resistance might occur due to decreased accumulation of PpIX in certain tumors. Such resistance may be caused by any fundamental step of PpIX accumulation: 5-ALA uptake, PpIX synthesis and PpIX efflux. MethodsWe investigated PpIX accumulation and photodynamically induced cell death in PDT refractory SCC-13, PDT susceptible A431, and normal human epidermal keratinocytes (NHEK). Expression of genes associated with cellular PpIX kinetics was investigated on mRNA and protein level. PpIX accumulation and cell death upon illumination were pharmacologically manipulated using drugs targeting 5-ALA uptake, PpIX synthesis or efflux. ResultsThe experiments indicate that taurine transporter (SLC6A6) is the major pathway for 5-ALA uptake in cSCC cells, while being less important in NHEK. Downregulation of PpIX synthesis enzymes in SCC-13 was counteracted by methotrexate (MTX) treatment, which restored PpIX formation and cell death. PpIX efflux inhibitors targeting ABC transporters led to significantly increased PpIX accumulation in SCC-13, thereby fully overcoming resistance. ConclusionsThe results indicate a conserved threshold for PpIX accumulation with respect to PDT-resistance. Cells showed increased viability after PDT at PpIX concentrations below 1.5 nM. Selective uptake of 5-ALA via taurine transporter SLC6A6 in cutaneous tumor cells is novel but unrelated to resistance. MTX can partially abrogate resistance by PpIX synthesis enzyme induction, while efflux mechanisms via ABC transporters seem the main driving force and promising drug targets.

Inhibition of cell survival and invasion by Tanshinone IIA via FTH1: A key therapeutic target and biomarker in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is a worldwide public health problem; its incidence is increasing and it is now the sixth most common cancer type worldwide. As indicated by existing studies, ferroptosis contributes to HNSCC progression and Tanshinone IIA (TanIIA) may exert therapeutic effects via affecting ferroptosis. However, the underlying mechanisms have remained to be clarified. Therefore, the main aim of the present study was to screen and investigate the key genes in regulating ferroptosis of the human hypopharynx squamous carcinoma cell line FaDu and further elucidate the mechanism of action of TanIIA. A list of ferroptosis-related genes was obtained from the FerrDb database. RNA-sequencing expression (level 3) profiles and corresponding clinical information (cases, n=502; normal controls, n=44) were downloaded from The Cancer Genome Atlas dataset for HNSCC (https://portal.gdc.com). The limma package in R software was used to study the differentially expressed mRNAs. Adjusted P<0.05 and Log2(fold change) >1 or <-1 were defined as the threshold for the differential expression of mRNAs. The ClusterProfiler package (version 3.18.0) in R was employed to analyze the Gene Ontology functional terms associated with potential targets and perform a Kyoto Encyclopedia of Genes and Genomes pathway analysis. The R package ggplot2 was used to draw the boxplot and the pheatmap package was used to draw the heatmap. The DEG-related protein-protein interaction network was built with the Search Tool for the Retrieval of Interacting Genes and proteins database and then the visualization was performed using Cytoscape. Ferritin heavy chain 1 (FTH1), transferrin (TF) and TF receptor were screened out using a Wayne diagram, which was drawn by the Venn Diagram package in R. Kaplan-Meier survival analysis and the log-rank test were used to compare differences in survival between the groups. The receiver operating characteristic (v 0.4) (ROC) curve analysis was used to compare the predictive accuracy of mRNAs. FTH1 was screened out and the expression results were verified using The Human Protein Atlas data. Immunohistochemistry and immunofluorescence were used to localize FTH1 expression in FaDu cells. Furthermore, Cell Counting Kit-8 and Transwell assays were used to detect the cell survival and invasion ability, respectively. Furthermore, western blot analysis was performed to analyze protein expression. The results of the present study indicated that three validated ferroptosis marker genes were differentially expressed in HNSCC, among which FTH1 was significantly associated with poorer survival. TanIIA was demonstrated to significantly affect FaDu cell survival and invasiveness and markedly attenuate FTH1 expression. To conclude, the ferroptosis gene FTH1 is highly expressed in HNSCC and TanIIA significantly inhibited HNSCC, partially by suppressing FTH1.

Abstract 5808: Diclofenac inhibits esophageal cancer cell growth by depleting mitochondrial functions

Abstract Esophageal cancer is one of the most aggressive forms of human malignancy with a 5-yearsurvival rate of less than 20%. Mitochondria are dynamic organelles that play essential roles in various cellular processes, including energy metabolism, redox homeostasis, and apoptotic cell death. Alterations in mitochondrial biology are associated with esophageal carcinogenesis and esophageal cancer cell response to therapy. As the anti-inflammatory drug diclofenac (DCF)induces mitochondrial dysfunction, we hypothesized that DCF may inhibit esophageal carcinogenesis by affecting mitochondrial processes. In the human esophageal squamous cell carcinoma (ESCC) cell line TE11, we performed MTT assay and Annexin-V/Propidium Iodide (PI) to evaluate the impact of DCF on proliferation and cell death, respectively. RNA sequencing and Ingenuity Pathway Analysis (IPA) identified differentially expressed genes (DEGs) and altered canonical pathways in DCF-treated TE11 cells. To assess metabolic function, we measured the levels of pyruvate, lactate, and ATP. Mitochondrial membrane potential and ROS production were assessed by flow cytometry for MitoTracker red/green and MitoSox red, respectively. Mice bearing subcutaneous syngeneic ESCC tumors were treated with DCF.DCF inhibited proliferation of TE11 in dose dependent manner with an IC50 concentration of 76.7µM. By contrast, the IC50 concentration of DCF in normal esophageal keratinocytes was 876.2µM, supporting selectivity of DCF for esophageal cancer cells. In TE11, 200 µM DCF induced apoptosis in 60% of cells. RNA-sequencing identified that DCF significantly altered expression of3287 genes (FC ≥ 1.50) in TE11, including the top cancer-associated genes: PLK1, MCM2, MCM3,MCM7, MCM10 and SKP2. IPA analysis revealed that DCF activated p53 signaling while inhibited Gluconeogenesis I, Glycolysis I and Oxidative Phosphorylation. DCF significantly inhibited glycolysis as demonstrated by reduction in concentrations of pyruvate (1.76-fold) and lactate (7.30-fold) and downregulation of the glycolysis- associated genes PKM2, PFKM, LDHA, and PKM1. A decreased production of ATP (5-fold) was also noted in DCF-treated TE11 cells. In addition, DCF depleted mitochondrial membrane potential (2.5-fold) and increased mitochondrial ROS production (5-fold). A reduction in ROS by mitochondrial antioxidant MitoTempo increased viability of the DCF-treated TE11 cells, indicating that ROS contributes to the anticancer activity of DCF. Consistent with antitumor activity of DCF in TE11, the drug significantly decreased the tumor volume in syngeneic ESCC tumors in vivo. Our preclinical findings indicate that DCF may limit esophageal cancer cell growth through the inhibition of mitochondrial functions, identifying a novel experimental therapeutic for ESCC. Future studies will define the precise molecular mechanisms through which DCF promotes cell death in vitro and in vivo. Citation Format: Mohammad Faujul Kabir, Adam Karami, Anbin Mu, Don-Gerard Conde, Kelly A. Whelan. Diclofenac inhibits esophageal cancer cell growth by depleting mitochondrial functions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5808.

Investigation of carbonic anhydrase inhibitory effects and cytotoxicities of pyrazole-based hybrids carrying hydrazone and zinc-binding benzenesulfonamide pharmacophores

Pyrazole-based carbohydrazone hybrids have been considered to be a remarkable class of compounds in pharmaceutical chemistry. Here, we reported bioactivities of 4-(3-(2-(arylidene)hydrazin-1-carbonyl)-5-phenyl-1H-pyrazol-1-yl)benzenesulfonamides (1–27) towards CA isoenzymes (hCA I, hCA II, hCA IX) and human oral squamous cell carcinoma cell line. Compounds 19 (Ki = 10.1 nM, hCA I/hCA IX = 749.6), 22 (Ki = 18.5 nM, hCA I/hCA IX = 429.2), 26 (Ki = 14.5 nM, hCA I/hCA IX = 596.9), 27 (Ki = 21.5 nM, hCA I/hCA IX = 413.1) were more potent and selective inhibitors of cancer-associated hCA IX isoenzyme. Compounds 22 and 26 were also found to be approximately three times more selective hCA IX inhibitors over off-target hCA II at low nanomolar. Compounds 19, 22, 23, 24, and 26 with IC50 of 1.6–1.7 μM showed potent cytotoxicity against human oral squamous cell carcinoma cell line as compared with human gingival fibroblast, producing the tumor-specificity value over 100. This was due to its cytostatic growth inhibition accompanied by a slight but significant dose-dependent increase in cell shrinkage and subG1 cell accumulation and marginal activation of caspase 3 substrates. Bioassay results showed that carbohydrazone-based hybrids could be useful candidates to design novel anticancer compounds and selective carbonic anhydrase inhibitors.

Assessing Gene Expression Related to Cisplatin Resistance in Human Oral Squamous Cell Carcinoma Cell Lines

Cisplatin-based chemotherapy has been effectively used to treat oral cancer, but treatment often fails owing to the development of drug resistance. However, the important gene expression alterations associated with these resistances remain unclear. In this study, we aimed to identify the gene expressions related to cisplatin resistance in oral squamous cell carcinoma (OSCC) cell lines. RNA samples were obtained from three cisplatin-resistant (YD-8/CIS, YD-9/CIS, and YD-38/CIS) and -sensitive (YD-8, YD-9, and YD-38) cell lines. Global gene expression was analyzed using RNA sequencing (RNA-Seq). Differentially expressed genes were determined. Based on the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, functional enrichment and signaling pathways analyses were performed. Candidate genes selected from RNA-Seq analysis were validated by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. The YD-8/CIS and YD-9/CIS samples had very similar expression patterns. qRT-PCR analysis was performed on selected genes commonly expressed between the two samples. The expression levels of 11 genes were changed in cisplatin-resistant samples compared with their parental samples; several of these genes were related to cell adhesion molecules and proteoglycans in cancer pathways. Our data provide candidate genes associated with cisplatin resistance in OSCC, but further study is required to determine which genes have an important role. Nevertheless, these results may provide new ideas to improve the clinical therapeutic outcomes of OSCC.

Schlafbezogene Atmungsstörungen, Hypoxämie und der Zusammenhang mit dem Lungenkarzinom

Sleep-disordered breathing (SDB) and chronic lung diseases have an increasing and even now high prevalence in the general population. Both SDB and chronic lung diseases cause hypoxemic states in affected patients, leading to pathophysiological changes known to be associated with cardiovascular diseases. Chronic lung diseases, such as chronic obstructive pulmonary disease (COPD) and SDB have also been described as being associated with an increased incidence of malignancies per se and especially lung cancer. This article reports on the previously known associations and pathophysiological mechanisms. The SDBs can be manifested in different forms as intermittent and/or chronic hypoxemia. These hypoxemia phenotypes affect vascular growth factors and tumor cell proliferation. Exposure of human lung carcinoma cells (human adenocarcinoma cell line H1437, human squamous cell carcinoma cell line H520) to hypoxemia leads to significantly increased proliferation rates with as yet unknown effects on the response to treatment and the long-term course. Likewise, the clinical effects of SDB and hypoxemia phenotypes on the immediate postoperative course after anatomical lung resections in lung cancer patients have not yet been clarified.

Induction of Human Oral Squamous Carcinoma Apoptosis by Derris scandens Benth and Elephantopus scaber Linn Extracts

D scandens ( Derris scandens Benth.) and E scaber ( Elephantopus scaber Linn.) contain flavonoids and phenolic acids, which have antitumor activity in various cancer cell lines. Oral cancer is among the most common cancers in Southeast Asia, and the survival rate remains low. Thus, this study screened 2 ethanolic plant extracts for cytotoxicity on the oral human squamous carcinoma cell line (HSC-2), and compared the mechanisms of action. Extracts of D scandens and E scaber showed cytotoxicity against HSC-2 cells in a dose-dependent manner. Observation of nuclear morphology by Hoechst 33342 staining revealed chromatin condensation. Apoptosis was confirmed by Annexin V-FITC staining and cell sorting (fluorescence-activated cell sorting) analysis. We demonstrated that cancer apoptosis was accompanied by changes in the expression of procaspase 3 and that D scandens-mediated apoptosis in HSC-2 cells was potentiated by protein kinase B (Akt) and B-cell lymphoma-2 (Bcl-2), while E scaber apoptosis was mediated by mitogen-activated protein kinase (MAPK) pathways, involving stress-activated protein kinases/jun amino-terminal kinase (SAPK/JNK) and p38-MAPK. Further investigation into targets for apoptosis induction by these plant extracts may have potential in oral cancer therapy.

Piper betle stem extract induces apoptosis through mitochondria inactivation, p38MAPK activation and ErB2/ErbB3 suppression on oral squamous cell carcinoma cells

BackgroundOral cancers are a group of carcinomas that appear in the oral cavity. The cause of oral cancer is still unclear. However, betel nut chewing, smoking and drinking alcohol are all known risk factors for oral cancers, among which the habit of chewing of betel nuts is known to be associated with the highest risk of oral cancer. Hypothesis/PurposeThis study aimed to examine the mechanisms of anti-cancer effects of the Piper betle (P. betle) stem. MethodsIn this study, MTT assays, cell morphology analysis and flow cytometry were employed to evaluate the anti-cancer effects of an extract of the P. betle stem on human oral squamous cell carcinoma cell lines Cal-27 and Ca9-22. Potential effects on cell proliferation and apoptotic molecular mechanisms were evaluated by western blotting. ResultsTreatment with P. betle stem extract inhibited cell proliferation in Cal-27 and Ca9-22 cells, and its effect on cell growth was mediated by a mechanism associated with apoptosis. The apoptotic cell death involved mitochondrial inactivation, causing downregulation of the expressions of Bcl-2 and Bcl-xl and increasing the expressions of Bax and Bad. Activation of p38MAPK and inhibition of the expressions of ErbB2 and ErbB3 were also involved in the P. betle stem extract-induced apoptosis in oral cancer cells. ConclusionThe findings from this study indicated that crude extract of the P. betle stem may regulate signaling pathways via apoptosis, suggesting that this extract has great potential for development as a new drug for the treatment of 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.

Extracellular N6 -isopentenyladenosine (i6A) addition induces cotranscriptional i6A incorporation into ribosomal RNAs.

N6 -isopentenyladenosine (i6A), a modified adenosine monomer, is known to induce cell death upon its addition to the culture medium. However, the molecular fate of extracellularly added i6A has yet to be identified. Here we show that i6A addition to cell culture medium results in i6A incorporation into cellular RNA in several cell lines, including the 5-fluorouracil (5-FU)-resistant human oral squamous cell carcinoma cell line FR2-SAS and its parental 5-FU-sensitive cell line SAS. i6A was predominantly incorporated into 18S and 28S rRNAs, and i6A incorporation into total RNA was mostly suppressed by treating these cell lines with an RNA polymerase I (Pol I) inhibitor. i6A was incorporated into RNA even upon inactivation of TRIT1, the only cellular i6A-modifying enzyme. These results indicate that upon cellular uptake of i6A, it is anabolized to be used for Pol I transcription. Interestingly, at lower i6A concentrations, the cytotoxic effect of i6A was substantially more pronounced in FR2-SAS cells than in SAS cells. Moreover, in FR2-SAS cells, i6A treatment decreased the rate of cellular protein synthesis and increased intracellular protein aggregation, and these effects were more pronounced than in SAS cells. Our work provides insights into the molecular fate of extracellularly applied i6A in the context of intracellular nucleic acid anabolism and suggests investigation of i6A as a candidate for a chemotherapy agent against 5-FU-resistant cancer cells.

Discovery of EP300/CBP histone acetyltransferase inhibitors through scaffold hopping of 1,4-oxazepane ring

EP300 and its paralog CBP play an important role in post-translational modification as histone acetyltransferases (HATs). EP300/CBP inhibition has been gaining attention as an anticancer treatment target in recent years. Herein, we describe the identification of a novel, highly selective EP300/CBP inhibitor, compound 11 (DS17701585), by scaffold hopping and structure-based optimization of a high-throughput screening hit 1. Compound 11 (DS17701585) shows dose-dependent inhibition of SRY-box transcription factor 2 (SOX2) mRNA expression in a human lung squamous cell carcinoma cell line LK2-xenografted mouse model.

Triclosan (TCS) affects the level of DNA methylation in the human oral squamous cell carcinoma (SCC-15) cell line in a nontoxic concentration

The oral cancer is presumably caused by genetic factors and exposure to substances derived from cosmetics and disinfectants. Triclosan (TCS) is widely spread in many consumer products and oral care products. Since TCS can affect DNA methylation, which is one of the key mechanisms of gene expression that may lead to cancerogenesis, it is necessary to study this mechanism in oral cell carcinoma. The aim of the present study was to evaluate the impact of TCS on metabolic parameters, oxidative stress, gene expression, and DNA methylation and hydroxymethylation in the SCC-15 cell line. The experiments have shown TCS toxicity to SCC-15 cells only in the highest concentrations of 50 and 100 µM. TCS in a wide range of concentrations increases ROS production and caspase-3 activity. Our experiments have shown that TCS in the nontoxic concentrations of 10 µM exerts an impact on SOD2 mRNA expression and SOD activity in the SCC-15 cell line. Finally, our experiments have demonstrated that 6-h treatment with TCS decreases the mRNA expression of DNMT3A and DNMT3B. After 72-h exposure to TCS, an increased level of 5-methylcytosine and 5-hydroxymethylcytosine was observed in the SCC-15 cell line, but it was abolished by the NAC treatment. However, it is very likely that these results can be an effect of TET enzyme activity, especially in the case of the decrease in 5mC and the increase in 5hmC after the 48-h exposure to TCS, which was accompanied with a decrease in the mRNA expression of DNMT3A and DNMT3B.

The Anti-Proliferative and Apoptotic Effects of Rutaecarpine on Human Esophageal Squamous Cell Carcinoma Cell Line CE81T/VGH In Vitro and In Vivo.

The overall five-year survival rate for patients with esophageal cancer is low (15 to 25%) because of the poor prognosis at earlier stages. Rutaecarpine (RTP) is a bioalkaloid found in the traditional Chinese herb Evodia rutaecarpa and has been shown to exhibit anti-proliferative effect on tumor cells. However, the mechanisms by which RTP confer these effects and its importance in esophageal squamous cell carcinoma treatment remain unclear. Thus, in the present study, we first incubated human esophageal squamous cell carcinoma cell line, CE81T/VGH, with RTP to evaluate RTP’s effects on tumor cell growth and apoptosis. We also performed a xenograft study to confirm the in vitro findings. Furthermore, we determined the expression of p53, Bax, bcl-2, caspase-3, caspase-9, and PCNA in CE81T/VGH cells or the tumor tissues to investigate the possible mechanisms. All the effects of TRP were compared with that of cisplatin. The results showed that RTP significantly inhibits CE81T/VGH cell growth, promotes arrest of cells in the G2/M phase, and induces apoptosis. Consistently, the in vivo study showed that tumor size, tumor weight, and proliferating cell nuclear antigen protein expression in tumor tissue are significantly reduced in the high-dose RTP treatment group. Furthermore, the in vitro and in vivo studies showed that RTP increases the expression of p53 and Bax proteins, while inhibiting the expression of Bcl-2 in cancer cells. In addition, RTP significantly increases the expression of cleaved caspase-9 and cleaved caspase-3 proteins in tumor tissues in mice. These results suggest that RTP may trigger the apoptosis and inhibit growth in CE81T/VGH cells by the mechanisms associated with the regulation of the expression of p53, Bax, Bcl-2, as well as caspase-9 and caspase-3.

Procyanidin B2 inhibits angiogenesis and cell growth in oral squamous cell carcinoma cells through the vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) pathway

ABSTRACT This study aimed to explore the therapy role of procyanidin B2 (PB2) in inhibiting angiogenesis and cell growth in oral squamous cell carcinoma. After oral mucosa epithelial cell (OMEC) and human oral squamous cell carcinoma (OSCC) cell line (SCC-25) were treated with PB2 or SCC-25 were treated with PB2 and rhVEGF, cell counting kit-8 (CCK-8) assay was used to determine the cell viability. The apoptosis, migration, invasion and angiogenesis of SCC-25 after indicated treatment were detected by Tunel, wound healing, transwell and tube formation assays. The protein expression related to apoptosis, metastasis and epithelial-mesenchymal transition (EMT) and changed expression of vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) signaling was analyzed by Western blot. As a result, PB2 inhibited viability, invasion, migration and EMT and promoted apoptosis of SCC-25 cells. In addition, PB2 inhibited VEGF/VEGFR2 signaling and tumor itangiogenesis in OSCC. As expected, activation of VEGF/VEGFR2 signaling suppressed the effect of PB2 on growth and metastasis of OSCC cells. In conclusion, PB2 inhibited the VEGF/VEGFR2 pathway to suppress the angiogenesis and cell growth of SCC-25 cells.