Tyrosol attenuates NASH features by reprogramming the hepatic immune milieu.

Nonalcoholic steatohepatitis (NASH) is a leading cause of chronic liver disease, and no drugs have been approved for its therapy. Among plant-derived molecules, phenolic compounds of extra virgin olive oil like tyrosol (Tyr) had demonstrated multiple beneficial actions for liver health, including the modulation of inflammation in fibrosis. This study aims at assessing the protective effect and mechanism of Tyr in invitro and in vivo models of NASH, with a focus on the hepatic immune microenvironment and extrahepatic manifestations. The effect of Tyr was evaluated in cellular models of NASH, obtained by co-culturing palmitic and oleic acid-treated HepG2 cells with THP1-derived M1 macrophages and LX2 cells, and in a mouse model of NASH induced by a high fructose-high fat diet combined to CCl4 treatment. In vitro Tyr reduced fatty acid (FA) accumulation in HepG2 cells and displayed a beneficial effect on LX2 activation and macrophage differentiation. In vivo, beside reducing steatosis and fibrosis in NASH animals, Tyr prevented inflammation, as demonstrated by the reduction of hepatic inflammatory foci, and immune cells like CD86+ macrophages (p < 0.05), CD4+ (p < 0.05) and T helper effector CD4+ FoxP3- CD62L-lymphocytes (p < 0.05). Also, the prooxidant enzyme NOX1 and the mRNA expression of TGF-ß1 and IL6 (p < 0.05) were reduced by Tyr. Notably, in Tyr-treated animals, a significant increase of CD4+ FoxP3+ Treg cells (p < 0.05) was observed, involved in regenerative pathways. Moreover, Tyr attenuated the fatigue and anxious behavior observed in NASH mice. In conclusion, Tyr effectively reduced NASH-related steatosis, fibrosis, oxidative stress, and inflammation, displaying a beneficial effect on the hepatic immune infiltrate, indicating its possible development as a therapeutic agent for NASH due to its multifaceted mechanism.

STARD3: A Prospective Target for Cancer Therapy.

Cancer is one of the major causes of death in developed countries and current therapies are based on surgery, chemotherapeutic agents, and radiation. To overcome side effects induced by chemo- and radiotherapy, in recent decades, targeted therapies have been proposed in second and even first lines. Targeted drugs act on the essential pathways involved in tumor induction, progression, and metastasis, basically all the hallmark of cancers. Among emerging pathways, the cholesterol metabolic pathway is a strong candidate for this purpose. Cancer cells have an accelerated metabolic rate and require a continuous supply of cholesterol for cell division and membrane renewal. Steroidogenic acute regulatory related lipid transfer (START) proteins are a family of proteins involved in the transfer of lipids and some of them are important in non-vesicular cholesterol transportation within the cell. The alteration of their expression levels is implicated in several diseases, including cancers. In this review, we report the latest discoveries on StAR-related lipid transfer protein domain 3 (STARD3), a member of the START family, which has a potential role in cancer, focusing on the structural and biochemical characteristics and mechanisms that regulate its activity. The role of the STARD3 protein as a molecular target for the development of cancer therapies is also discussed. As STARD3 is a key protein in the cholesterol movement in cancer cells, it is of interest to identify inhibitors able to block its activity.

Carbon dots for cancer nanomedicine: a bright future.

Cancer remains one of the main causes of death in the world. Early diagnosis and effective cancer therapies are required to treat this pathology. Traditional therapeutic approaches are limited by lack of specificity and systemic toxicity. In this scenario, nanomaterials could overcome many limitations of conventional approaches by reducing side effects, increasing tumor accumulation and improving the efficacy of drugs. In the past few decades, carbon nanomaterials (i.e., fullerenes, carbon nanotubes, and carbon dots) have attracted significant attention of researchers in various scientific fields including biomedicine due to their unique physical/chemical properties and biological compatibility and are among the most promising materials that have already changed and will keep changing human life. Recently, because of their functionalization and stability, carbon nanomaterials have been explored as a novel tool for the delivery of therapeutic cancer drugs. In this review, we present an overview of the development of carbon dot nanomaterials in the nanomedicine field by focusing on their synthesis, and structural and optical properties as well as their imaging, therapy and cargo delivery applications.

Cuban Brown Propolis Interferes in the Crosstalk between Colorectal Cancer Cells and M2 Macrophages.

Tumor-associated macrophages (TAMs), primarily the M2 phenotype, are involved in the progression and metastasis of colorectal cancer (CRC). Cuban brown propolis (Cp) and its main component Nemorosone (Nem) displays an antiproliferative effect on different cancer cells, including CRC cell lines. However, whether Cp and Nem could exploit its effect on CRC cells by targeting their relationship with TAMs remains to be elucidated. In this study, we differentiated the human monocytic THP-1 cells to M2 macrophages and confirmed this transition by immunofluorescence (IF) staining, qRT-PCR and zymography. An MTT assay was performed to determine the effect of Cp and Nem on the viability of CRC HT-29 cells co-cultured with M2 macrophages. Furthermore, the migration and invasion abilities of HT-29 cells were determined by Transwell assays and the expression levels of epithelial-mesenchymal transition (EMT) markers were analyzed by IF staining. We demonstrated that Cp and Nem reduced the viability of M2 macrophages and, accordingly, the activity of the MMP-9 metalloprotein. Moreover, we demonstrated that M2 macrophages produce soluble factors that positively regulate HT-29 cell growth, migration and invasion. These M2-mediated effects were counteracted by Cp and Nem treatments, which also played a role in regulating the expression of the EMT markers E-cadherin and vimentin. Taken together, our results indicate that Nem contained in Cp interferes in the crosstalk between CRC cells and TAMs, by targeting M2 macrophages.

The Cuban Propolis Component Nemorosone Inhibits Proliferation and Metastatic Properties of Human Colorectal Cancer Cells.

The majority of deaths related to colorectal cancer (CRC) are associated with the metastatic process. Alternative therapeutic strategies, such as traditional folk remedies, deserve attention for their potential ability to attenuate the invasiveness of CRC cells. The aim of this study is to investigate the biological activity of brown Cuban propolis (CP) and its main component nemorosone (NEM) and to describe the molecular mechanism(s) by which they inhibit proliferation and metastatic potential of 2 CRC cell lines, i.e., HT-29 and LoVo. Our results show that CP and NEM significantly decreased cell viability and inhibited clonogenic capacity of CRC cells in a dose and time-dependent manner, by arresting the cell cycle in the G0/G1 phase and inducing apoptosis. Furthermore, CP and NEM downregulated BCL2 gene expression and upregulated the expression of the proapoptotic genes TP53 and BAX, with a consequent activation of caspase 3/7. They also attenuated cell migration and invasion by inhibiting MMP9 activity, increasing E-cadherin and decreasing ß-catenin and vimentin expression, proteins involved in the epithelial-mesenchymal transition (EMT). In conclusion NEM, besides displaying antiproliferative activity on CRC cells, is able to decrease their metastatic potential by modulating EMT-related molecules. These finding provide new insight about the mechanism(s) of the antitumoral properties of CP, due to NEM content.

Nemorosone inhibits the proliferation and migration of hepatocellular carcinoma cells.

AIMS: In the tumor microenvironment, dysregulated immune cells could promote tumor progression, invasion and metastasis, by establishing a symbiotic relationship with cancer cells. A pivotal role is played by monocyte recruitment and induction of tumor-associated macrophages (TAMs), which provide immunosuppression and tumorigenesis. The effect of nemorosone, an antiproliferative phytocomponent present in Cuban Propolis, on TAM-induced tumor progression remains to be elucidated. Here we investigated the symbiotic relationship between monocytic leukemia THP-1 and hepatocellular carcinoma HepG2 cells, and the role of nemorosone in preventing TAM-induced tumor growth. MAIN METHODS: Macrophage differentiation induced by HepG2-conditioned medium was assessed by flow cytometry, analysis of secreted molecules and cytokine expression. The effect of nemorosone and/or conditioned THP-1-medium on HepG2 proliferation was evaluated by MTT assay, colony formation, cells cycle and migration assays. KEY FINDINGS: HepG2 cells induced THP-1 recruitment and differentiation to macrophages. When compared with control THP-1 cells, differentiated THP-1 showed a significant increase of the matrix metalloproteinases MMP-2 and MMP-9 expression (P < 0.01), and slightly induced HepG2 cells growth. This effect was counteracted by nemorosone, which also significantly inhibited colony formation (P < 0.01) and migratory capacity of HepG2 cells, driving a high percentage of cells (80%) to the G0/G1 phase. SIGNIFICANCE: HepG2-conditioned medium is a suitable model for THP-1 modulation and differentiation. Moreover, nemorosone significantly inhibits the proliferation of HepG2 cells, both in presence and absence of the soluble factors secreted by TAMs. Further studies are needed to elucidate the role of this natural compound in the HCC-TAM relationship.

Chemosensitizing activity of Cuban propolis and nemorosone in doxorubicin resistant human colon carcinoma cells.

Propolis is a natural product obtained from bees, used since ancient times for its multiple pharmacological properties. Several evidences indicate that the antiproliferative effect of propolis against different cancer cell lines can be ascribed to its components. However, little is known about the possible use of this natural product in the treatment of chemo-resistant tumors. Combination experiments were carried out in order to study the ability of Cuban propolis extracts (CP) and its main component (nemorosone) to chemosensitize doxorubicin-resistant human colon carcinoma cells (LoVo Dox) compared to the sensitive cells (LoVo). Antiproliferative effect was determined by MTT assay after 24, 48 and 72 h exposure. Synergistic, additive or antagonistic effects of different combined treatments (CP-Dox and nemorosone-Dox), was evaluated by isobologram-combination index method. The interaction mechanisms between CP or nemorosone with doxorubicin were studied by flow cytometry to investigate cell death pathway and cell cycle arrest. Reactive oxygen species production (ROS) and mitochondrial membrane potential (ΔΨm) modification were also evaluated. Data showed that both CP and its main component nemorosone were able to reduce cell proliferation in a concentration- and time-dependent manner. Combined treatments induced a cell growth inhibition with a significantly synergistic antiproliferative and cytotoxic effect. Co-treatments induced also cell cycle arrest which results in apoptosis by a marked ROS production and drastic alteration of ΔΨm. In summary, our findings evidence the potential role of Cuban propolis extracts and their main component nemorosone as new chemosensitizing agents against drug-resistant human colon carcinoma cells.

Rhopalurus junceus scorpion venom induces antitumor effect in vitro and in vivo against a murine mammary adenocarcinoma model.

OBJECTIVES: In Cuba the endemic scorpion species Rhopalurus junceus has been used in traditional medicine for cancer treatment and related diseases. However there is no scientific evidence about its therapeutic potential for cancer treatment. The aim of the study was to determine the antitumor effect of scorpion venom against a murine mammary adenocarcinoma F3II. MATERIALS AND METHODS: The cytotoxic activity was determined by MTT assay with venom concentrations ranging from 0.1-1 mg/ml. Apoptosis was determined by RT-PCR and flow cytometry. Toxic effect in healthy animals and tumor growth kinetics in F3II bearing-mice were evaluated by using scorpion venom doses (0.2; 0.8; 3.2 mg/kg) after one and ten injections respectively by the intraperitoneal route . RESULTS: Scorpion venom induced a significant cytotoxic effect (P<0.05) in F3II cells in a concentration-dependent manner. The cell death event involves the apoptotic pathway due to up-regulation of pro-apoptotic genes (p53, bax), down-regulation of antiapoptotic gene (bcl-2), and 33% of Annexin V+/PI- cells at early apoptosis and 10.21% of Annexin V+/PI+ cells at late apoptosis. Scorpion venom induced significant inhibition of tumor progression (P<0.05) in F3II bearing-mice in a dose-dependent manner. The antitumor effect was confirmed due to dose-dependent reduction of Ki-67 and CD31 proteins present in tumor tissue. CONCLUSION: Evidence indicates that scorpion venom can be an attractive natural product for deep investigation and developing a novel therapeutic agent for breast cancer treatment.

The cytotoxic effects of propolis on breast cancer cells involve PI3K/Akt and ERK1/2 pathways, mitochondrial membrane potential, and reactive oxygen species generation.

Propolis has been extensively used to improve health and prevent inflammatory diseases. Different types of Cuban propolis (red, brown and yellow) have been documented. The purpose of this research was to investigate the cytotoxic effects of Cuban red propolis (CP) on MDA MB-231 cell line, since breast cancer is considered one of the most common causes of mortality among women. Antiproliferative and cytotoxic activity of CP against MDA MB-231 cells were determined by the 3-[4,5-dimethylth-iazol-2-yl]-2,5-diphenyl tetrazoliumbromide (MTT) and lactate dehydrogenase (LDH) assays. Apoptosis/necrosis, involvement of PI3K/Akt and ERK1/2 pathways, mitochondrial membrane potential and expression of genes were investigated. CP extract exhibited antiproliferative and cytotoxic effects on MDA MB-231 cells, what may be probably related to PI3K/Akt and ERK1/2 pathways. A decreased expression of apoptosis-related genes (TP53, CASP3, BAX and P21) was seen, whereas the expressions of BCL-2, BCL-XL, NOXA and PUMA were unaffected. CP extract induced mitochondrial dysfunction and LDH release, what indicated cell necrosis associated with reactive oxygen species production and decreased cell migration. Our findings provide a basis for future investigation of chemopreventive and/or therapeutic studies against apoptosis-resistant breast cancer, in animals and humans.

Targeting RORs nuclear receptors by novel synthetic steroidal inverse agonists for autoimmune disorders.

Designing novel inverse agonists of NR RORγt still represents a challenge for the pharmaceutical community to develop therapeutics for treating immune diseases. By exploring the structure of NRs natural ligands, the representative arotenoid ligands and RORs specific ligands share some chemical homologies which can be exploited to design a novel molecular structure characterized by a polycyclic core bearing a polar head and a hydrophobic tail. Compound MG 2778 (8), a cyclopenta[a]phenantrene derivative, was identified as lead compound which was chemically modified at position 2 in order to obtain a small library for preliminary SARs. Cell viability and estrogenic activity of compounds 7, 8, 19a, 30, 31 and 32 were evaluated to attest selectivity. The selected 7, 8, 19a and 31 compounds were assayed in a Gal4 UAS-Luc co-transfection system in order to determine their ability to modulate RORγt activity in a cellular environment. They were evaluated as inverse agonists taken ursolic acid as reference compound. The potency of compounds was lower than that of ursolic acid, but their efficacy was similar. Compound 19a was the most active, significantly reducing RORγt activity at low micromolar concentrations.

Mechanisms underlying the cytotoxic effect of propolis on human laryngeal epidermoid carcinoma cells.

Propolis has been used as a traditional remedy for centuries because of its beneficial effects, including anticancer properties. The aim of this study was to compare the cytotoxic mechanism of Cuban red propolis (CP) and Brazilian green propolis (BP) on human laryngeal carcinoma (HEp-2) cells. Cell viability, leakage of lactate dehydrogenase, fluorescence staining, mitochondrial membrane potential (ΔΨm) and the expression of pro/anti-apoptotic genes were assessed. Cell viability and cytotoxic assays suggested a dose-dependent effect of CP and BP extracts with a possible association of intracellular reactive oxygen species production and decreased ΔΨm. Both samples induced apoptosis via activation of TP53, CASP3, BAX, P21 signalling, and downregulation of BCL2 and BCL-XL. CP exerted a higher cytotoxic effect than BP extract. Our findings suggest further investigation of the main components of each propolis sample, what may lead to the development of strategies for the treatment of laryngeal cancer.

Mechanisms involved in the cytotoxic action of Brazilian propolis and caffeic acid against HEp-2 cells and modulation of P-glycoprotein activity.

OBJECTIVES: The effects of propolis and phenolic compounds (caffeic acid - Caf; dihydrocinnamic acid - Cin; p-coumaric acid - Cou) in the same quantity found in our propolis sample were investigated on human laryngeal epidermoid carcinoma (HEp-2) cells. METHODS: Cell viability, apoptosis/necrosis and cell cycle arrest, P53 and CASPASE-3 gene expression, generation of reactive oxygen species (ROS) and the ability of propolis to induce doxorubicin (DOX) efflux using a P-glycoprotein (P-gp) inhibitor (verapamil) were assayed. KEY FINDINGS: Propolis exerted a cytotoxic effect on HEp-2 cells, whereas isolated compounds had no effect on cell viability. Higher concentrations were tested and Caf induced late apoptosis or necrosis in HEp-2 cells, while propolis induced apoptosis, both probably due to ROS generation. P53 expression was downregulated by propolis but not by Caf. CASPASE-3 expression was correlated with induction of both early and late apoptosis, with both propolis and Caf alone upregulating its expression. Propolis induced cell cycle arrest at G2/M phase and Caf at S phase. Propolis but not Caf may act as a P-gp inhibitor by modulating P-gp activity and inhibiting DOX efflux. CONCLUSIONS: Propolis exerted cytotoxic effects on HEp-2 cells, and the mechanisms are discussed, showing its potential as an antitumour drug.

Combinatorial effects of geopropolis produced by Melipona fasciculata Smith with anticancer drugs against human laryngeal epidermoid carcinoma (HEp-2) cells.

The identification of natural products exerting a combined effect with therapeutic agents could be an alternative for cancer treatment, reducing the concentration of the drugs and side effects. Geopropolis (Geo) is produced by some stingless bees from a mixture of vegetable resins, gland secretions of the bees and soil. It has been used popularly as an antiseptic agent and to treat respiratory diseases and dermatosis. To determine whether Geo enhances the anticancer effect of carboplatin, methotrexate and doxorubicin (DOX), human laryngeal epidermoid carcinoma (HEp-2) cells were treated with Geo alone or in combination with each drug. Cell growth, cytotoxicity and apoptosis were evaluated using 3-(4,5-dimethyl thiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay, lactate dehydrogenase (LDH) release, and flow cytometry. Scratch assay was used to analyze cell migration and transmission electron microscopy to observe morphologic alterations. The influence of Geo on drug resistance was also investigated assessing P-glycoprotein (P-gp) action. Geo inhibited cell proliferation and migration. The combination Geo+DOX led to the highest cytotoxic activity and induced apoptosis, leading to loss of membrane integrity. Geo had no effect on P-gp-mediated efflux of DOX. Data indicate that Geo combined with DOX could be a potential clinical chemotherapeutic approach for laryngeal cancer treatment.

Evaluación de la citotoxicidad de extractos marinos sobre un panel de líneas celulares / Evaluation of cytotoxicity of different marine extracts in a cell line panel

Introducción: los extractos naturales provenientes de fuentes marinas representan una importante fuente en el descubrimiento de nuevos compuestos con potencialidades como anticarcinogénicos. Objetivos: determinar el efecto de cinco extractos provenientes de diferentes organismos marinos sobre la viabilidad de un panel de cinco líneas celulares (A549, HEp-2, MDA-MB-231, SiHa y MRC-5). Metodos: el efecto de los extractos (Physalia physali, Cassiopea xamachana, Tripneustes ventricosus, Echinometra lucunter) se determinó mediante el ensayo colorimétrico con el empleo de bromuro de 3(4,5 dimetil-2-tiazoil)-2,5-difeniltetrazolio. Mediante de RT-PCR se determinó adicionalmente el efecto del extracto de Echinometra lucunter sobre la expresión de los genes apoptóticos p53, survivin, bcl-xL y noxa en SiHa. Resultados: todos los extractos afectaron la viabilidad celular de la línea normal MRC-5 de pulmón humano. Sin embargo, no disminuyeron la viabilidad de las líneas celulares de origen tumoral con excepción del extracto de Echinometra lucunter. Este extracto solo afectó la viabilidad de la línea celular tumoral SiHa. Los valores de las concentraciones inhibitorias medias (CI50) mostraron que solo para el extracto de Echinometra lucunter, la línea celular tumoral SiHa evidenció una CI50 de 52,07±11 μg/mL que es significativamente inferior a MRC-5 con una CI50 de 98,6±14 μg/mL, por lo que se muestra selectividad frente a las células tumorales. Adicionalmente, el extracto disminuyó significativamente la expresión de los genes proapoptóticos lo que sugiere la muerte celular por necrosis en las células SiHa. Conclusiones: el extracto proveniente de Echinometra lucunter resultó selectivo frente a las células tumorales SiHa. Experimentos que incluyan otras líneas celulares de cáncer cérvicouterino podrían confirmar el potencial de este extracto frente a esta variedad histológica de cáncer(AU)

Introduction: natural extracts from marine sources represent an important source for the discovery of new compounds with anti-carcinogenic potentialities. Objectives: to determine the effect of five extracts from several marine organisms pm the viability of a panel of five cell lines (A549, HEp-2, MDA-MB-231, SiHa y MRC-5). Methods: the effects of the extracts (Physalia physali, Cassiopea xamachana, Tripneustes ventricosus, Echinometra lucunter) were then determined by using the colorimetric assay with 3 (4,5 dimethyl-2-tiazoil)/2,5-difeniltetrazolium bromide. Additionally, the effect of extract of Echinometra lucunter was determined on the expression of apoptotic genes p53, survivin, bcl-xL and noxa in SiHa. Results: all the extracts affected the cell viability of the normal cell line MRC-5 of the human lung. However, viability of tumoral cell lines did not decrease except for the extract from Echinometra lucunter. This extract just affected the viability of tumor cell line SiHa. The mean inhibitory concentrations (IC50) showed that only for Echinometra lucunter extract, the tumor cell line SiHa revealed a IC50 of 52,07±11 μg/mL that is significantly lower than that of MRC-5 with IC50 of 98,6±14 μg/mL, therefore the selectivity against the tumor cells was shown. Moreover, the extract markedly decreased the expression of propapoptosis genes, thus indicating the cell death from necrosis in SIHa cells.Conclusions: extract from Echinometra lucunter was selective against tumor cells SiHa. Other experiments that will include other cervix uterine cancer cell lines can confirm the potential of this extract to have an effect on this histological cancer type(AU)

Evaluación de la citotoxicidad de extractos marinos sobre un panel de líneas celulares / Evaluation of cytotoxicity of different marine extracts in a cell line panel

Introducción: los extractos naturales provenientes de fuentes marinas representan una importante fuente en el descubrimiento de nuevos compuestos con potencialidades como anticarcinogénicos. Objetivos: determinar el efecto de cinco extractos provenientes de diferentes organismos marinos sobre la viabilidad de un panel de cinco líneas celulares (A549, HEp-2, MDA-MB-231, SiHa y MRC-5). Metodos: el efecto de los extractos (Physalia physali, Cassiopea xamachana, Tripneustes ventricosus, Echinometra lucunter) se determinó mediante el ensayo colorimétrico con el empleo de bromuro de 3(4,5 dimetil-2-tiazoil)-2,5-difeniltetrazolio. Mediante de RT-PCR se determinó adicionalmente el efecto del extracto de Echinometra lucunter sobre la expresión de los genes apoptóticos p53, survivin, bcl-xL y noxa en SiHa. Resultados: todos los extractos afectaron la viabilidad celular de la línea normal MRC-5 de pulmón humano. Sin embargo, no disminuyeron la viabilidad de las líneas celulares de origen tumoral con excepción del extracto de Echinometra lucunter. Este extracto solo afectó la viabilidad de la línea celular tumoral SiHa. Los valores de las concentraciones inhibitorias medias (CI50) mostraron que solo para el extracto de Echinometra lucunter, la línea celular tumoral SiHa evidenció una CI50 de 52,07±11 µg/mL que es significativamente inferior a MRC-5 con una CI50 de 98,6±14 µg/mL, por lo que se muestra selectividad frente a las células tumorales. Adicionalmente, el extracto disminuyó significativamente la expresión de los genes proapoptóticos lo que sugiere la muerte celular por necrosis en las células SiHa. Conclusiones: el extracto proveniente de Echinometra lucunter resultó selectivo frente a las células tumorales SiHa. Experimentos que incluyan otras líneas celulares de cáncer cérvicouterino podrían confirmar el potencial de este extracto frente a esta variedad histológica de cáncer(AU)

Introduction: natural extracts from marine sources represent an important source for the discovery of new compounds with anti-carcinogenic potentialities. Objectives: to determine the effect of five extracts from several marine organisms pm the viability of a panel of five cell lines (A549, HEp-2, MDA-MB-231, SiHa y MRC-5). Methods: the effects of the extracts (Physalia physali, Cassiopea xamachana, Tripneustes ventricosus, Echinometra lucunter) were then determined by using the colorimetric assay with 3 (4,5 dimethyl-2-tiazoil)/2,5-difeniltetrazolium bromide. Additionally, the effect of extract of Echinometra lucunter was determined on the expression of apoptotic genes p53, survivin, bcl-xL and noxa in SiHa. Results: all the extracts affected the cell viability of the normal cell line MRC-5 of the human lung. However, viability of tumoral cell lines did not decrease except for the extract from Echinometra lucunter. This extract just affected the viability of tumor cell line SiHa. The mean inhibitory concentrations (IC50) showed that only for Echinometra lucunter extract, the tumor cell line SiHa revealed a IC50 of 52,07±11 µg/mL that is significantly lower than that of MRC-5 with IC50 of 98,6±14 µg/mL, therefore the selectivity against the tumor cells was shown. Moreover, the extract markedly decreased the expression of propapoptosis genes, thus indicating the cell death from necrosis in SIHa cells. Conclusions: extract from Echinometra lucunter was selective against tumor cells SiHa. Other experiments that will include other cervix uterine cancer cell lines can confirm the potential of this extract to have an effect on this histological cancer type(AU)

Brazilian green propolis induced apoptosis in human lung cancer A549 cells through mitochondrial-mediated pathway.

OBJECTIVES: Propolis effect on the growth and apoptosis of human lung adenocarcinoma (A549 cells) was investigated as well as its mechanisms. METHODS: Cells were incubated with propolis for 72 h, and 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays were employed to assess cell viability and the inhibitory concentration (IC). Apoptosis was detected by Acridine Orange/Ethidium Bromide and 4',6-diamidino-2-phenylindole staining after 24 and 48 h of incubation with » IC50 of propolis by testing the mitochondrial membrane potential (ΔΨm) and the expression of apoptosis-related genes (p53, Caspase-3, Bax, Bcl-2, Bcl-XL , Noxa, Puma and p21) by reverse transcription polymerase chain reaction. KEY FINDINGS: Propolis displayed antiproliferative and cytotoxic effects on A549 cells in a dose- and time-dependent manner, but it did not suppress the growth of normal Vero cells. An enhanced apoptosis was seen in A549 propolis-treated cells after 48 h compared with the control cells. Propolis decreased mitochondrial membrane potential by overexpression of pro-apoptotic genes (Bax and Noxa) and reduction of the antiapoptotic gene Bcl-XL . The expression level of other genes remained unchanged (p53, Caspse-3 and Bax), whereas p21 expression was increased. Propolis induced caspase-independent apoptosis through a p53-independent mitochondrial pathway, and cell cycle arrest by upregulation of p21. CONCLUSIONS: Although propolis induces apoptosis mainly by p53-independent manner, it may be induced by another pathway, and new insights may arise for preventing or treating lung cancer.

In vitro anticancer effect of venom from Cuban scorpion Rhopalurus junceus against a panel of human cancer cell lines.

In Cuba the endemic species of scorpion Rhopalurus junceus has been used in traditional medicine for cancer treatment. However, there is little scientific evidence about its potential in cancer therapy. The effect of a range of scorpion venom concentrations (0.1, 0.25, 0.5, 0.75 and 1mg/ml) against a panel of human tumor cell lines from epithelial (Hela, SiHa, Hep-2, NCI-H292, A549, MDA-MB-231, MDA-MB-468, HT-29), hematopoietic origins (U937, K562, Raji) and normal cells (MRC-5, MDCK, Vero) was determined by the MTT assay. Additionally, the effect of venom on tumor cell death was assayed by Fluorescence microscopy, RT-PCR and western blot. Only the epithelial cancer cells showed significant cell viability reduction, with medium cytotoxic concentration (IC50) ranging from 0.6-1mg/ml, in a concentration-dependent manner. There was no effect on either normal or hematopoietic tumor cells. Scorpion venom demonstrated to induce apoptosis in less sensitive tumor cells (Hela) as evidenced by chromatin condensation, over expression of p53 and bax mRNA, down expression of bcl-2 mRNA and increase of activated caspases 3, 8, 9. In most sensitive tumor cells (A549), scorpion venom induced necrosis evidenced by acridine orange/ethidium bromide fluorescent dyes and down-expression of apoptosis-related genes. We concluded the scorpion venom from R. junceus possessed a selective and differential toxicity against epithelial cancer cells. This is the first report related to biological effect of R. junceus venom against a panel of tumor cells lines. All these results make R. junceus venom as a promise natural product for cancer treatment.