Effect of Piper cubeba total extract and isolated lignans on head and neck cancer cell lines and normal fibroblasts.

The objective of the present study was to evaluate the action of the crude hydroalcoholic extract of Piper cubeba fruits and isolated lignans (cubebin, dihydrocubebin, ethylcubebin, hinokinin and methylcubebin) on head and neck cancer cells. We evaluated the influence of the Piper cubeba extract and isolated lignans (10, 50 e 100 µg/mL) for 4, 24, 48 and 72 h, in the larynx (Hep-2) and oral (SCC-25) squamous cell carcinoma cells and normal fibroblasts, on morphology, cell proliferation and migration, cytotoxicity, genotoxicity and gene and protein expression (PTGS2, PTGER3, PTGER4, MMP2, MMP9). The results showed that the P. cubeba extract and different lignans do not alter the cellular morphology, but decrease cell proliferation and migration, have low cytotoxic and genotoxic effects, probably due to the alteration of the expression of genes and proteins involved with inflammatory process. From these data, we can conclude that the lignans cubebin and methylcubebin had a greater effect on head and neck cancer cells in the antiproliferative, antimigratory and genotoxic action, and could be the target of the development of new therapies including possible new drugs as a therapeutic resource for the treatment of head and neck cancer due to its immense range of biological properties.

Annexin A1 Mimetic Peptide Ac2-26 Modulates the Function of Murine Colonic and Human Mast Cells.

Mast cells (MCs) are main effector cells in allergic inflammation and after activation, they release stored (histamine, heparin, proteases) and newly synthesized (lipid mediators and cytokines) substances. In the gastrointestinal tract the largest MC population is located in the lamina propria and submucosa whereas several signals such as the cytokine IL-4, seem to increase the granule content and to stimulate a remarkable expansion of intestinal MCs. The broad range of MC-derived bioactive molecules may explain their involvement in many different allergic disorders of the gastrointestinal tract. Annexin A1 (AnxA1) is a 37 KDa glucocorticoid induced monomeric protein selectively distributed in certain tissues. Its activity can be reproduced by mimetic peptides of the N-terminal portion, such as Ac2-26, that share the same receptor FPR-L1. Although previous reports demonstrated that AnxA1 inhibits MC degranulation in murine models, the effects of exogenous peptide Ac2-26 on intestinal MCs or the biological functions of the Ac2-26/FPR2 system in human MCs have been poorly studied. To determine the effects of Ac2-26 on the function of MCs toward the possibility of AnxA1-based therapeutics, we treated WT and IL-4 knockout mice with peptide Ac2-26, and we examined the spontaneous and compound 48/80 stimulated colonic MC degranulation and cytokine production. Moreover, in vitro, using human mast cell line HMC-1 we demonstrated that exogenous AnxA1 peptide is capable of interfering with the HMC-1 degranulation in a direct pathway through formyl peptide receptors (FPRs). We envisage that our results can provide therapeutic strategies to reduce the release of MC mediators in inflammatory allergic processes.

Hydrogen peroxide and Helicobacter pylori extract treatment combined with APE1 knockdown induce DNA damage, G2/M arrest and cell death in gastric cancer cell line.

Chronic inflammation resulting from Helicobacter pylori (H. pylori) infection, the major risk factor for gastric cancer, results in increased release of reactive oxygen species (ROS), promoting oxidative stress and DNA damage. APE1 endonuclease, a key component of the base excision repair (BER) pathway, is responsible for the repair of damage induced by ROS. However, the APE1 gene and other DNA damage response (DDR) genes are still poorly understood in gastric cancer. Thus, we aimed to investigate whether the silencing of APE1 by shRNA can interfere with the survival of AGS gastric cancer cells after treatment with hydrogen peroxide (H2O2) and/or H. pylori extract (HPE) and its relation with the expression of DDR genes (ATM, ATR, and H2AX) and miRNAs that target DDR genes. In the AGS cells expressing APE1, isolated or combined treatment with H2O2 and HPE promoted a slight increase in the cell proliferation and increased the levels of intracellular ROS and DNA double strand breaks (DSBs) indicated by ©H2AX foci, a reduction in the proportion of cells in the G0/G1 phase and an increase in the initial apoptosis rate. Moreover, upregulation of APE1, ATR, miR-15a, miR-21, miR-24 and miR-421 and downregulation of ATM and H2AX was observed. In silenced AGS cells after treatment with H2O2 alone or combined with HPE, we observed an increase in the cell proliferation rate and the levels of intracellular ROS and DSBs and a reduction in the proportion of cells in S and G2/M phase arrest, leading to late apoptosis. APE1 knockdown also caused a reduction in the expression of ATM and miR-421, while ATR expression was increased. Based on our results, APE1 knockdown may promote changes in cellular processes by increasing genomic instability, leading to G2/M arrest and cell apoptosis, so it may be a promising strategy for controlling tumor progression.

Cisplatin treatment modulates Annexin A1 and inhibitor of differentiation to DNA 1 expression in cervical cancer cells.

Cisplatin (Cis) is a choice chemotherapy approach to cervical cancer by inducing DNA adducts and subsequent apoptosis. We have investigated the effects of Cis on Annexin A1 (ANXA1) and inhibitor of DNA binding 1 (ID1) proteins expression to elucidate further mechanisms of Cis actions. Human cervical tissue samples from twenty-four patients, with Cervical Intraepithelial Neoplasia (CIN, stage I, II and III), were evaluated to quantified ANXA1 and ID1 expressions. In vitro, human epidermoid carcinoma of the cervix (SiHa cell line) were treated with Annexin A1 peptide (ANXA12-26), Cis or Cis + ANXA12-26 to evaluate cell proliferation and migration, cytotoxicity of treatments as well as ANXA1 and ID1 modulations by mRNA and protein expression. Our findings showed expression of ID1 and ANXA1 proteins in tissue samples from Cervical Intraepithelial Neoplasia (CIN) patients, with intense immunological identification of ID1 in the CIN III stage. In SiHa cells, treatments with Cis alone or Cis + ANXA12-26, increase mRNA expressions of the ANXA1 and reduced the ID1. In agreement, Cis + ANXA12-26 enhanced ANXA1 protein expression and Cis or Cis + ANXA12-26 abolished ID1 protein expression. Cell proliferation was reduced after treatment with ANXA12-26 peptide and more significant after Cis or Cis + ANXA12-26 treatments. These two last treatments reduced cell viability, by inducing late apoptosis, and impaired cell migration. Together, our data highlight endogenous ANXA1 is involved in Cis therapy for cervical cancer.

Euphorbia tirucalli modulates gene expression in larynx squamous cell carcinoma.

BACKGROUND: Some plants had been used in the treatment of cancer and one of these has attracted scientific interest, the Euphorbia tirucalli (E. tirucalli), used in the treatment of asthma, ulcers, warts has active components with activities scientifically proven as antimutagenic, anti-inflammatory and anticancer. METHODS: We evaluate the influence of the antitumoral fraction of the E. tirucalli latex in the larynx squamous cell carcinoma (Hep-2), on the morphology, cell proliferation and gene expression. The Hep-2 cells were cultivated in complete medium (MEM 10 %) and treated with E. tirucalli latex for 1, 3, 5 and 7 days. After statistically analyzing the proliferation of the tested cells, the cells were cultivated again for RNA extraction and the Rapid Subtractive Hybridization (RaSH) technique was used to identify genes with altered expression. The genes found using the RaSH technique were analyzed by Gene Ontology (GO) using Ingenuity Systems. RESULTS: The five genes found to have differential expression were validated by real-time quantitative PCR. Though treatment with E. tirucalli latex did not change the cell morphology in comparison to control samples, but the cell growth was significantly decreased. The RaSH showed change in the expression of some genes, including ANXA1, TCEA1, NGFRAP1, ITPR1 and CD55, which are associated with inflammatory response, transcriptional regulation, apoptosis, calcium ion transport regulation and complement system, respectively. The E. tirucalli latex treatment down-regulated ITPR1 and up-regulated ANXA1 and CD55 genes, and was validated by real-time quantitative PCR. CONCLUSIONS: The data indicate the involvement of E. tirucalli latex in the altered expression of genes involved in tumorigenic processes, which could potentially be applied as a therapeutic indicator of larynx cancer.

ANXA1Ac2₋26 peptide reduces ID1 expression in cervical carcinoma cultures.

Cervical cancer is the second most frequent cancer in women worldwide and is associated with genetic alterations, infection with human papilloma virus (HPV), angiogenesis and inflammatory processes. The idea that inflammation is involved in tumorigenesis is supported by the frequent appearance of cancer in areas of chronic inflammation. On the other hand, the inflammatory response is controlled by the action of anti-inflammatory mediators, among these mediators, annexin A1 (ANXA1), a 37 kDa protein was detected as a modulator of inflammatory processes and is expressed by tumor cells. The study was carried out on the epithelial cancer cell line (SiHa) treated with the peptide of annexin A1 (ANXA1Ac2-26). We combined subtraction hybridization approach, Ingenuity Systems software and quantitative PCR, in order to evaluate gene expression influenced by ANXA1. We observed that ANXA1Ac2-26 inhibited proliferation in SiHa cells after 72h. In these cells, 55 genes exhibited changes in expression levels in response to peptide treatment. Six genes were selected and the expression results of 5 up-regulated genes (TPT1, LDHA, NCOA3, HIF1A, RAB13) and one down-regulated gene (ID1) were research by real time quantitative PCR. Four more genes (BMP4, BMPR1B, SMAD1 and SMAD4) of the ID1 pathway were investigated and only one (BMPR1B) shows the same down regulation. The data indicate the involvement of ANXA1Ac2-26 in the altered expression of genes involved in tumorigenic processes, which could potentially be applied as a therapeutic indicator of cervical cancer.