Antitumor Effect of Açaí (Euterpe oleracea Mart.) Seed Extract in LNCaP Cells and in the Solid Ehrlich Carcinoma Model.

Euterpe oleracea (açaí) fruit has approximately 15% pulp, which is partly edible and commercialized, and 85% seeds. Although açaí seeds are rich in catechins-polyphenolic compounds with antioxidant, anti-inflammatory, and antitumor effects-almost 935,000 tons/year of seeds are discarded as industrial waste. This work evaluated the antitumor properties of E. oleracea in vitro and in vivo in a solid Ehrlich tumor in mice. The seed extract presented 86.26 ± 0.189 mg of catechin/g of extract. The palm and pulp extracts did not exhibit in vitro antitumor activity, while the fruit and seed extracts showed cytotoxic effects on the LNCaP prostate cancer cell line, inducing mitochondrial and nuclear alterations. Oral treatments were performed daily at 100, 200, and 400 mg/kg of E. oleracea seed extract. The tumor development and histology were evaluated, along with immunological and toxicological parameters. Treatment at 400 mg/kg reduced the tumor size, nuclear pleomorphism, and mitosis figures, increasing tumor necrosis. Treated groups showed cellularity of lymphoid organs comparable to the untreated group, suggesting less infiltration in the lymph node and spleen and preservation of the bone marrow. The highest doses reduced IL-6 and induced IFN-γ, suggesting antitumor and immunomodulatory effects. Thus, açaí seeds can be an important source of compounds with antitumor and immunoprotective properties.

Açai (Euterpe oleracea Mart.) Seed Extract Induces ROS Production and Cell Death in MCF-7 Breast Cancer Cell Line.

Euterpe oleracea Mart. (açai) is a native palm from the Amazon region. There are various chemical constituents of açai with bioactive properties. This study aimed to evaluate the chemical composition and cytotoxic effects of açai seed extract on breast cancer cell line (MCF-7). Global Natural Products Social Molecular Networking (GNPS) was applied to identify chemical compounds present in açai seed extract. LC-MS/MS and molecular networking were employed to detect the phenolic compounds of açai. The antioxidant activity of açai seed extract was measured by DPPH assay. MCF-7 breast cancer cell line viability was evaluated by MTT assay. Cell death was evaluated by flow cytometry and time-lapse microscopy. Autophagy was evaluated by orange acridin immunofluorescence assay. Reactive oxygen species (ROS) production was evaluated by DAF assay. From the molecular networking, fifteen compounds were identified, mainly phenolic compounds. The açai seed extract showed cytotoxic effects against MCF-7, induced morphologic changes in the cell line by autophagy and increased the ROS production pathway. The present study suggests that açai seed extract has a high cytotoxic capacity and may induce autophagy by increasing ROS production in breast cancer. Apart from its antioxidant activity, flavonoids with high radical scavenging activity present in açai also generated NO (nitric oxide), contributing to its cytotoxic effect and autophagy induction.

Marine-Derived Penicillium purpurogenum Reduces Tumor Size and Ameliorates Inflammation in an Erlich Mice Model.

BACKGROUND: This study addresses the antitumoral properties of Penicillium purpurogenum isolated from a polluted lagoon in Northeastern Brazil. METHODS: Ethyl Acetate Extracellular Extract (EAE) was used. The metabolites were studied using direct infusion mass spectrometry. The solid Ehrlich tumor model was used for antitumor activity. Female Swiss mice were divided into groups (n = 10/group) as follows: The negative control (CTL-), treated with a phosphate buffered solution; the positive control (CTL+), treated with cyclophosphamide (25 mg/kg); extract treatments at doses of 4, 20, and 100 mg/kg; animals without tumors or treatments (Sham); and animals without tumors treated with an intermediate dose (EAE20). All treatments were performed intraperitoneally, daily, for 15 days. Subsequently, the animals were euthanized, and the tumor, lymphoid organs, and serum were used for immunological, histological, and biochemical parameter evaluations. RESULTS: The extract was rich in meroterpenoids. All doses significantly reduced tumor size, and the 20 and 100 mg/kg doses reduced tumor-associated inflammation and tumor necrosis. The extract also reduced the cellular infiltration of lymphoid organs and circulating TNF-α levels. The extract did not induce weight loss or renal and hepatic toxic changes. CONCLUSIONS: These results indicate that P. purpurogenum exhibits immunomodulatory and antitumor properties in vivo. Thus, fungal fermentation is a valid biotechnological approach to the production of antitumor agents.

Could Increased Expression of Hsp27, an "Anti-Inflammatory" Chaperone, Contribute to the Monocyte-Derived Dendritic Cell Bias towards Tolerance Induction in Breast Cancer Patients?

Dendritic cells (DCs) are the most efficient antigen-presenting cells and link the innate immune sensing of the environment to the initiation of adaptive immune responses, which may be directed to either acceptance or elimination of the recognized antigen. In cancer patients, though DCs would be expected to present tumor antigens to T lymphocytes and induce tumor-eliminating responses, this is frequently not the case. The complex tumor microenvironment subverts the immune response, blocks some effector mechanisms, and drives others to support tumor growth. Chronic inflammation in a tumor microenvironment is believed to contribute to the induction of such regulatory/tolerogenic response. Among the various mediators of the modulatory switch in chronic inflammation is the "antidanger signal" chaperone, heat shock protein 27 (Hsp27), that has been described, interestingly, to be associated with cell migration and drug resistance of breast cancer cells. Thus, here, we investigated the expression of Hsp27 during the differentiation of monocyte-derived DCs (Mo-DCs) from healthy donors and breast cancer patients and evaluated their surface phenotype, cytokine secretion pattern, and lymphostimulatory activity. Surface phenotype and lymphocyte proliferation were evaluated by flow cytometry, interferon- (IFN-) γ, and interleukin- (IL-) 10 secretion, by ELISA and Hsp27 expression, by quantitative polymerase chain reaction (qPCR). Mo-DCs from cancer patients presented decreased expression of DC maturation markers, decreased ability to induce allogeneic lymphocyte proliferation, and increased IL-10 secretion. In coculture with breast cancer cell lines, healthy donors' Mo-DCs showed phenotype changes similar to those found in patients' cells. Interestingly, patients' monocytes expressed less GM-CSF and IL-4 receptors than healthy donors' monocytes and Hsp27 expression was significantly higher in patients' Mo-DCs (and in tumor samples). Both phenomena could contribute to the phenotypic bias of breast cancer patients' Mo-DCs and might prove potential targets for the development of new immunotherapeutic approaches for breast cancer.