Synthesis of Tridax procumbens mediated TiO2 nanoparticles, investigation of antibacterial and anti-cancer activity against selected oral pathogens.

The genus Calophyllum (Calophyllaceae), distributed mainly in tropical regions, is rich in chromanone derivatives with diverse molecular structures that exhibit potential antimicrobial and anticancer effects. Phytochemical investigation of the stem bark of C. calaba collected in Thailand led to the discovery of eight previously undescribed chromanones, calabanones A-H (1‒8), and two known analogs, (‒)-isocalomembranone P (9) and (‒)-calomembranone P (10). The chemical structures of undescribed compounds were elucidated using spectroscopic analyses, particularly NMR and HRESIMS, while their absolute configurations were determined through ECD and NMR calculations combined with DP4+ probability analysis. Compounds 7 and 8 were identified as chromanone-steroid hybrids linked via an ester bond, representing the first report of such structures in plants. Cytotoxic evaluation of the isolated specialized metabolites revealed that compounds 6 and 9 displayed moderate activity against KB and HeLa S3 cancer cell lines, with IC50 values ranging from 12.71 to 25.50μM, while compounds 3‒5 selectively inhibited the growth of KB cells, with IC50 values in the range of 18.77‒27.06μM.

Background Oral squamous cell carcinoma (OSCC) signifies a major global health issue, defined by its destructive nature and often delayed diagnosis, leading to suboptimal prognoses. The global case and mortality rates of OSCC continue to increase, especially among younger populations. Purpose This work aims to study the anti-cancer properties of crebanine on oral cancer KB cells by inducing apoptosis via suppressing PI3K/AKT/mTOR and JAK-2/STAT-3 pathways. Materials and Methods Crebanine at various doses (0.5–25 µM) was evaluated for its in vitro free-radical scavenging properties, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), peroxyl, and superoxide radicals. The impact of crebanine on the growth of oral cancer KB and normal Vero cells was evaluated with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. The mitochondrial membrane potential (MMP) level in untreated and crebanine-treated KB cells was assessed using a fluorescent staining assay. The oxidative stress markers, apoptosis-related proteins, and PI3K/AKT/mTOR and JAK-2/STAT-3 pathway proteins were evaluated in untreated and crebanine-treated KB cells. Results The findings of the free radical scavenging experiments demonstrated the in vitro anti-oxidant properties of crebanine. The findings of the MTT experiment revealed that crebanine considerably inhibited the viability of KB cells without significantly affecting the normal Vero cells. The crebanine treatment reduced the MMP level in KB cells, as demonstrated by the findings of the fluorescent staining assay. The crebanine-treated KB cells exhibited elevated thiobarbituric acid reactive substances (TBARS) levels, alongside decreased glutathione (GSH) and superoxide dismutase (SOD) levels. Furthermore, crebanine treatment enhanced the pro-apoptotic proteins Bax and caspase-3/9 levels, while concurrently inhibiting the PI3K/AKT/mTOR and JAK-2/STAT-3 signaling protein levels in KB cells. Conclusion The current study demonstrates that crebanine treatment can impede cellular proliferation, trigger oxidative stress, and facilitate apoptosis in KB cells via downregulating PI3K/AKT/mTOR and JAK-2/STAT-3 pathways.

Background Oral cancer is a major type of head and neck cancer that mostly affects the lips, tongue, buccal mucosa, and salivary glands. It is a malignant tumor affecting the oral cavity with an annual incidence of over half a million new cases. Purpose The major aim of the current work is to evaluate the anti-cancer potential of marrubiin against oral cancer KB cells. Materials and Methods The effect of marrubiin (2.5–160 µg/mL) on KB cell growth was assessed by the MTT assay. The mitochondrial membrane potential (MMP) and apoptosis in the marrubiin-treated and control cells were studied using respective fluorescent staining assays. The angiogenic marker vascular endothelial growth factor (VEGF) and inflammatory cytokines tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6) levels were studied using the assay kits. Results The MTT assay results prove that the marrubiin treatment effectively decreased KB cell growth dose-dependently. The treatment of marrubiin at an inhibitory concentration (IC 50 33.15 µg/mL) effectively induced apoptosis and reduced MMP levels in the KB cells. The VEGF, TNF-α, and IL-6 levels were effectively reduced in the KB cells after treatment with the IC 50 concentration of marrubiin. Conclusion The present results demonstrate that marrubiin inhibits cell viability and promotes apoptosis in KB cells via decreasing VEGF and inflammatory cytokine levels. Thus, it holds potential as a promising anti-cancer agent for treating oral cancer.

Oral cancer is a predominant and aggressive form of head and neck cancer with limited treatment options. Stevioside, a naturally occurring biocompatible compound, has gained attention for its potential therapeutic properties, although its molecular mechanistic role in OSCC merely understood. This study aims to elucidate the impact of stevioside on OSCC cells, focusing on its inhibitory effects on cell proliferation and epithelial-mesenchymal transitions (EMT). KB cells, representative of OSCC, were subjected to stevioside treatment in a time-dependent manner. The findings obtained from the MTT assay revealed a notable suppression of KB cell growth following 48 hours of treatment with stevioside. The IC<inf>50</inf> values, which represent the concentration at which the inhibitory effect of stevioside is at 50% at 110.54 µM, as determined by this assay, were subsequently utilized further for the analysis of gene expression through RT-PCR. Furthermore, our investigation involved the examination of EMT-related genes (ECADH, SNAIL1, SLUG, and VIM) using molecular docking analysis. In conclusion, this study sheds light on the significant role of stevioside in oral cancer. The observed inhibition of KB cell proliferation and its pronounced impact on EMT-related gene expression indicate the potential of stevioside as a promising therapeutic agent in the context of OSCC. The multifaceted effects of stevioside on OSCC cells present an exciting avenue for advancing our understanding of this devastating disease and the development of innovative therapeutic strategies.

Polyprenylated benzoylphloroglucinols (PPBPs) make up a group of complex natural products with anticancer potentials that are mainly distributed in Garcinia plants. As part of our intensive exploration on new bioactive substances from this genus, we report two undescribed PPBPs, picrorhizones I (1) and J (2), along with four known analogues (3-6) from the stem bark of Garcinia picrorhiza and Garcinia gracilis. The new structures were elucidated on the basis of spectroscopic analysis, particularly 1D and 2D NMR and HRESIMS, whereas the absolute configurations were determined by a combination of ECD and NMR calculations coupled with a DP4+ probability analysis. Being the least class in genus Garcinia, picrorhizone I possesses a type-A structure with the position of a benzoyl moiety attaching to one of the bridgehead carbons of a bicyclo[3.3.1]nonane skeleton, which differs from its major type-B counterparts. This work also represents the first report on the occurrence of PPBPs in G. gracilis. The cytotoxic evaluation of the isolated compounds revealed that isogarcinol (4) and garciyunnanin L (5) significantly inhibited the growth of KB and Hela S3 cancer cells with IC50 values lower than 10 μM, while 5 was also strongly active against the Hep G2 cancer cell line with an IC50 value of 8.02 μM. Among the B-class derivatives bearing a lavandulyl side chain, cyclization of the moiety in the bicyclic phloroglucinol skeleton enhanced the cytotoxic properties on cancer cells.

11-Azaartemisinin derivatives bearing halogenated aromatic moieties: Potent anticancer agents with high tumor selectivity

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.

The aim of the present study was to investigate the effect of Solanum xanthocarpum on KB human oral cancer cells by analyzing its anti-proliferative and apoptotic properties as well as its inhibitory effect on cell adhesion. In this study, the leaves extract of S. xanthocarpum was prepared using the maceration method. Cytotoxic effect of different doses of the S. xanthocarpum extract was assessed using MTT assay. Measurements of reactive oxygen species (ROS), lipid peroxidation and antioxidant enzymes were also performed. In addition, we also studied the impacts of S. xanthocarpum on the apoptosis and mitochondrial membrane potential of KB cells. Determination of antioxidant enzymes and lipid peroxidation was performed using biochemical methods. The S. xanthocarpum showed cytotoxic activity against KB cells with IC50 (200 μg/mL). Besides, DCFH-DA staining and acridine orange/ethidium bromide staining results demonstrated that S. xanthocarpum induced the generation of ROS and apoptosis in KB cells, respectively. Based on the Rh-123 staining results, S. xanthocarpum decreased mitochondrial depolarization in KB cells. Furthermore, the S. xanthocarpum treatment contributed to increased lipid peroxidation, accompanied by reduced activities of superoxide dismutase and catalase, as well as decreased glutathione content. Taken together, these findings indicate that S. xanthocarpum extract might comprise bioactive compounds of therapeutic significance, which can inhibit the growth of KB cells.

Synthesis, Computational and cytotoxicity studies of aryl hydrazones of β-diketones: Selective Ni2+ metal Responsive fluorescent chemosensors

Poly(hydroxyethyl acrylate-co-phenyl vinyl sulfide) (P(HEA-co-PVS)), as an oxidizable amphiphilic polymer, was prepared for the fabrication of an oxidation- and temperature-responsive micelle for the delivery of doxorubicin (DOX). The interfacial activity of H2O2-treated P(HEA-co-PVS) was significantly lower than that of the untreated variety, possibly because of the oxidization of PVS. P(HEA-co-PVS) exhibited a lower critical solution temperature (LCST) behavior and the LCST increased upon H2O2 treatment. The copolymer micelles, prepared by the dialysis method, were found to be round particles (less than 100 nm) on TEM micrograph. The release degree of Nile red loaded in the micelles was higher when the H2O2 concentration was higher, possibly because the micelles could be solubilized more readily at a higher H2O2 concentration. The release degree was more strongly dependent on the oxidizing agent concentration when the temperature was higher. DOX loaded in the micelles suppressed the in vitro growth of KB cells (a human cancer cell type originating from the cervix) much more effectively than DOX loaded in an unoxidizable control micelle and free DOX, possibly because the copolymer would undergo an increase in its LCST, lose its amphiphilic property, and the micelles would be disassembled. The DOX-loaded micelles were readily internalized into KB cells, as evidenced by flow cytometry (FACS) and confocal laser scanning microscopy (CLSM).

Plants with anticancer properties are considered as cancer preventive and treatment sources, due to their some biological effects. Apoptosis induction and anti-proliferative effects of Baneh extract on various cancer cell lines have been reported. Hence, this study was designed to evaluate the cytotoxic effects of this fruit on KB and human gingival fibroblast cell lines (HGF). KB and HGF cells were treated with various concentrations of ethanolic Baneh extract and cisplatin as positive control. Cytotoxic activity and apoptosis induction were investigated using WST-1 and Annexin V assays. Data were analyzed using ANOVA and student's t-tests. IC50 after 24 and 48 hours treatment were respectively 2.6 and 1 mg/mL for KB cell line, and 1.5 and 1.6 mg/mL for HGF cell. During 48 hours Baneh extract induced apoptosis without significant necrosis, in a time- and dose-dependent manner. The induction of apoptosis in KB cells was significantly higher than HGF. It seems that ethanolic extract of Baneh contains compounds that can suppress KB cell growth through the induction of apoptosis. Within 48 hours, less cytotoxic effects were observed on normal fibroblast cells; therefore, it might be a potential anticancer agent.

ABSTRACTCrocin and safranal are active ingredients in the saffron. Some studies have demonstrated antitumor activities of saffron ingredients. The aim of this study was to evaluate cytotoxic effects of crocin and safranal in oral squamous cell carcinoma (KB cells) and NIH 3T3 cell line as nonmalignant cells. The cells were incubated with crocin and safranal at 37°C for 24, 48, and 72 h, and cell viability was quantitated by MTT assay. Apoptotic cells, cell cycle distribution, and sub-G1 fraction were determined using propidium iodide staining of DNA fragmentation by flow cytometry. Crocin (0.05–4 mM) and safranal (0.2–3.2 mM) significantly inhibited the growth of KB cells (the inhibitory growth effects of all concentrations for both were >50% after 72 h), while they had less inhibitory effects on NIH 3T3 cells viability. The IC50 values of crocin and safranal against NIH 3T3 cells after 72 h were determined as 2.8 and 0.3 mM, respectively. Crocin and safranal induced a sub-G1 peak in the flow cytometry histogram of treated cells compared to control cells indicating that apoptotic cell death is involved in the toxicity of crocin and safranal. Apoptotic effects of crocin and safranal in tumor cells were more than normal cells. Neither crocin nor safranal affected the cell cycle progression. Crocin and safranal exerted apoptotic effects in KB cell line.

Background: Cytotoxic effects of Frankincense resin have been shown on some cancer cell lines. Due to its low side effects, this study was designed to evaluate the anticancer properties of water soluble elements of Frankincense oleo-gum-resin on human oral squamous cell carcinoma cell line. Methods: Oleo-gum-resin was macerated in ethanol. After filtration, the water soluble fraction of dried residue was extracted. KB cells were treated with 0, 62.5, 125, 250 and 500 μg/mL concentrations of obtained Frankincense aqueous fractions and with Doxorubicin as positive control. Frankincense induced cell cytotoxicity; apoptosis and proliferation were investigated using WST assay, Annexin V-FITC/PI, and Ki-67 staining, respectively. Data were analyzed using Kruskal-Wallis test by SPSS 17 software. Results: IC50 of 137.21 μg/mL was obtained from Frankincense aqueous fraction after 48 hours. The percentage of apoptotic cells was elevated in a time- and dose-dependent manner. There was no statistical difference in the Ki-67 expression of KB cells, using different concentration of Frankincense aqueous fraction after 24 and 48 hours (P = 0.083). Doxorubicin inhibited cells growth essentially through apoptosis. Conclusions: Frankincense aqueous fractions seem to suppress KB cell growth through the induction of apoptosis and necrosis rather than the inhibition of proliferation and hence might be a potential anticancer agent. Structural analysis and purification of potent components are suggested for determining more definitive results.

2-Amino-4-oxo-6-substituted-pyrrolo[2,3-d]pyrimidine antifolate thiophene regioisomers of AGF94 (4) with a thienoyl side chain and three-carbon bridge lengths [AGF150 (5) and AGF154 (7)] were synthesized as potential antitumor agents. These analogues inhibited proliferation of Chinese hamster ovary (CHO) sublines expressing folate receptors (FRs) α or β (IC50s < 1 nM) or the proton-coupled folate transporter (PCFT) (IC50 < 7 nM). Compounds 5 and 7 inhibited KB, IGROV1, and SKOV3 human tumor cells at subnanomolar concentrations, reflecting both FRα and PCFT uptake. AGF152 (6) and AGF163 (8), 2,4-diamino-5-substituted-furo[2,3-d]pyrimidine thiophene regioisomers, also inhibited growth of FR-expressing CHO and KB cells. All four analogues inhibited glycinamide ribonucleotide formyltransferase (GARFTase). Crystal structures of human GARFTase complexed with 5 and 7 were reported. In severe combined immunodeficient mice bearing SKOV3 tumors, 7 was efficacious. The selectivity of these compounds for PCFT and for FRα and β over the ubiquitously expressed reduced folate carrier is a paradigm for selective tumor targeting.

One known cyclic peptide, beauvericin, was isolated from the secondary metabolites of mangrove endophytic fungi Fusarium sp. (No. DZ27) in South China Sea. Its structure was determined by spectral analyses and comparisons with reference data from literatures. Beauvericin inhibited growth of KB and KBv200 cells potently with IC50 values of 5.76 ± 0.55 and 5.34 ± 0.09 μM, respectively. Furthermore, beauvericin induced apoptosis through mitochondrial pathway, including decrease of relative oxygen species generation, loss of mitochondrial membrane potential, release of cytochrome c, activation of Caspase-9 and -3, and cleavage of PARP. Additionally, regulation of Bcl-2 or Bax was not involved in the apoptosis induced by beauvericin in KB and KBv200 cells.

Effects of diphenyl difluoroketone (EF-24) and curcumin on cell growth and apoptosis induction in KB human oral cancer cells were examined. EF-24 and curcumin inhibited the growth of KB cells in a dose-dependent manner, and the potency of EF-24 was 30 times greater than that of curcumin. Treatment with EF-24 or curcumin resulted in nuclear condensation and fragmentation. EF-24 and curcumin promoted the proteolytic cleavage of procaspases-3, -7, and -9. Activities of caspases-3 and -7 were detected in living KB cells treated with EF-24 or curcumin. These results suggest that EF-24 and curcumin inhibit cell proliferation and induce apoptosis in KB human oral cancer cells, and have potential properties for development of anti oral cancer drug.

We synthesized several novel bifunctional alkylating derivatives of 3a-aza-cyclopenta[a]indene (BO-1012, BO-1005, BO-1099 and BO-1101) that are potent DNA interstrand crosslinking agents. In in vitro cytotoxicity assay, these compounds were more cytotoxic to multidrug-resistant (MDR) cells, such as KBvin10, KBtax50 and CEM/VBL, than their parental cells. Using a xenograft model, BO-1012, at a dose of 5 mg/kg, partially suppressed the growth of parental KB cells but completely suppressed the growth of KBvin10 cells in nude mice. In exploring the possible mechanism, we found that DNA double-strand break (DSB) repair activity in MDR cells, KBvin10 and CEM/VBL, was significantly reduced compared with their parental cells, KB and CEM. Reduced DSB repair activity in KBvin10 cells was likely due to a defect in nuclear translocation of DNA-dependent protein kinase (DNA-PK), a component of the non-homologous end-joining repair machinery. Furthermore, BO-1012-induced DNA-PK translocation from the cytosol into the nucleus in KB cells is associated with the activation of the Src/nuclear epidermal growth factor receptor (EGFR) cascade, which is defective in MDR cells. As knockdown of P-glycoprotein (P-gp) by siRNA reactivated the Src/nuclear EGFR cascade, DNA-PK translocation and DNA repair activity in MDR cells, overexpression of P-gp attenuates the activity of DNA DSB repair through suppression of Src/nuclear EGFR cascade. Therefore, DNA interstrand crosslinking agents may have potential therapeutic use against P-gp-overexpressing MDR cells.

Abstract ABSTRACT Terbinafine (TB), an oral antifungal agent used in the treatment of superficial mycosis, has been reported to exert an anti-tumor effect in various cancer cells. However, the effect of TB on oral cancer has not been evaluated. Herein we demonstrated that TB (0-60 μM) concentration-dependently decreased cell number in cultured human oral squamous cell carcinoma (OSCC), KB cells. The anti-proliferation effect of TB was also observed in two other OSCC cell lines, SAS and SCC 15. TB (60 μM) was not cytotoxic and its inhibition on KB cell growth was reversible. [3H]thymidine incorporation and flow cytometric analyses revealed that TB inhibited DNA synthesis and induced the G0/G1 cell cycle arrest. The TB-induced cell cycle arrest occurred when the cyclin-dependent kinase 2 (CDK2) activity was inhibited just as the protein levels of p21cip1 and p27kip1 were increased. The TB-induced G0/G1 cell cycle arrest was completely blocked when the expressions of p21cip1 and p27kip1 were knocked-down together. Taken together, these results suggest that the p21cip1- and p27kip1-associated signaling pathways might be involved in the TB-induced anti-proliferation in KB cells. In vivo, TB (50 mg/kg, i.p.) significantly inhibited the KB tumor size. In these TB-treated tumors, increases in the levels of p21cip1 and p27kip1 protein and decreases in the number of proliferating cell nuclear antigen (PCNA)-positive cells and the microvessel density (MVD) were observed. These findings demonstrate for the first time that TB might have potential to serve as a therapeutic tool in the treatment of oral cancer. 1 Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3040. doi:1538-7445.AM2012-3040

Abstract Experimentation and tests with cells in culture and cell synchronization or synchrony are important in order to be able to make both reliable and high-sensitivity measurements. This is also very important for mechanistic studies of cell division control, oncogenesis and tumor growth. A comparison is made in this article between the initially synchronized cell growth of rabbit and KB cells in synchronized cultures.