forrás: http://medpublics.com/docs/Fruit_peel_polyphenols.pdf
2021-06-09 11:43:06
Abstract Purpose Fruit and vegetable intake is inversely correlated with cancer; thus, it is proposed that an extract of phytochemicals as present in whole fruits, vegetables, or grains may have anti-carcinogenic properties. Thus, the anti-tumour effects of fruit peel polyphenols (Flavin7) in the chemoprevention of N-methyl-N-nitrosourea-induced mammary carcinogenesis in female rats were evaluated. Methods Lyophilized substance of Flavin7 (F7) was administered at two concentrations of 0.3 and 3 % through diet. The experiment was terminated 14 weeks after carcinogen administration, and mammary tumours were removed and prepared for histopathological and immunohistochemical analysis. In addition, using an in vitro cytotoxicity assay, apoptosis and proliferation after F7 treatment in human breast adenocarcinoma (MCF-7) cells were performed. Results High-dose F7 suppressed tumour frequency by 58 % (P < 0.001), tumour incidence by 24 % (P < 0.05), and lengthened latency by 8 days (P > 0.05) in comparison with the control rats, whereas lower dose of F7 was less effective. Histopathological analysis of tumours showed significant decrease in the ratio of high-/low-grade carcinomas after high-dose F7 treatment. Immunohistochemical analysis of rat carcinoma cells in vivo found a significant increase in caspase-3 expression and significant decrease in Bcl-2, Ki67, and VEGFR-2 expression in the highdose group. Both doses demonstrated significant positive effects on plasma lipid metabolism in rats. F7 significantly decreased survival of MCF-7 cells in vitro in MTT assay by dose- and time-dependent manner compared to control. F7 prevented cell cycle progression by significant enrichment in G1 cell populations. Incubation with F7 showed
forrás: http://www.ncbi.nlm.nih.gov/pubmed/24631140
2014-04-15 12:36:18
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE:
Hericium is a genus of mushrooms (fungus) in the Hericiaceae family. Hericium erinaceus (HE) has been used for the treatment of digestive diseases for over 2000 years in China. HE possesses many beneficial functions such as anticancer, antiulcer, antiinflammation and antimicrobial effects, immunomodulation and other activities. The aim of the studies was to evaluate the anticancer efficacy of two extracts (HTJ5 and HTJ5A) from the culture broth of HE against three gastrointestinal cancers such as liver, colorectal and gastric cancers in both of in vitro of cancer cell lines and in vivo of tumor xenografts and discover the active compounds.
MATERIALS AND METHODS:
Two HE extracts (HTJ5 and HTJ5A) were used for the studies. For the study of chemical constituents, the HTJ5 and HTJ5A were separated using a combination of macroporous resin with silica gel, HW-40 and LH-20 chromatography then purified by semipreparative high-performance liquid chromatography (HPLC) and determined by nuclear magnetic resonance (NMR) spectra. For the in vitro cytotoxicity studies, HepG2 and Huh-7 liver, HT-29 colon, and NCI-87 gastric cancer cell lines were used and MTT assay was performed to determine the in vitro cytotoxicity. For in vivo antitumor efficacy and toxicity studies, tumor xenograft models of SCID mice bearing liver cancer HepG2 and Huh-7, colon cancer HT-29 and gastric cancer NCI-87 subcutaneously were used and the mice were treated with the vehicle control, HTJ5 and HTJ5A orally (500 and 1000mg/kg/day) and compared to 5-fluorouraci (5-FU) at the maximum tolerated dose (MTD, 25-30mg/kg/day) intraperitoneally daily for 5 days when the tumors reached about 180-200mg (mm(3)). Tumor volumes and body weight were measured daily during the first 10 days and 2-3 times a week thereafter to assess the tumor growth inhibition, tumor doubling time, partial and complete tumor response and toxicity.
RESULTS:
Twenty-two compounds were obtained from the fractions of HTJ5/HTJ5A including seven cycli dipeptides, five indole, pyrimidines, amino acids and derivative, three flavones, one anthraquinone, and six small aromatic compounds. HTJ5 and HTJ5A exhibited concentration-dependent cytotoxicity in vitro against liver cancer HepG2 and Huh-7, colon cancer HT-29, and gastric cancer NCI-87 cells with the IC50 in 2.50±0.25 and 2.00±0.25, 0.80±0.08 and 1.50±0.28, 1.25±0.06 and 1.25±0.05, and 5.00±0.22 and 4.50±0.14mg/ml; respectively. For in vivo tumor xenograft studies, HTJ5 and HTJ5A showed significantly antitumor efficacy against all four xenograft models of HepG2, Huh-7, HT-29 and NCI-87 without toxicity to the host. Furthermore, HTJ5 and HTJ5A are more effective than that of 5-FU against the four tumors with less toxicity.
CONCLUSION:
HE extracts (HTJ5 and HTJ5A) are active against liver cancer HepG2 and Huh-7, colon cancer HT-29 and gastric cancer NCI-87 cells in vitro and tumor xenografts bearing in SCID mice in vivo. They are more effective and less toxic compared to 5-FU in all four in vivo tumor models. The compounds have the potential for development into anticancer agents for the treatment of gastrointestinal cancer used alone and/or in combination with clinical used chemotherapeutic drugs. However, further studies are required to find out the active chemical constituents and understand the mechanism of action associated with the super in vivo anticancer efficacy. In addition, future studies are needed to confirm our preliminary results of in vivo synergistic antitumor efficacy in animal models of tumor xenografts with the combination of HE extracts and clinical used anticancer drugs such as 5-FU, cisplatin and doxurubicin for the treatment of gastrointestinal cancers.
forrás: http://www.ncbi.nlm.nih.gov/pubmed/7750093
2014-03-11 14:21:47
Rapid cell death, as evidenced by a decrease in cell counts, was observed when molt-4-lymphoblastoid cells, a human leukemia cell line, were exposed to holotransferrin (12 microM) and dihydroartemisinin (1-200 microM). Incubation with either compound alone was significantly less effective. Significantly less cell death was observed when normal human lymphocytes were exposed to a combination of these 2 drugs. Probit analysis of doseresponse functions shows that the drug combination is approximately 100 times more effective on molt-4 cells than lymphocytes (LD50s for molt-4 and lymphocytes were 2.59 microM and 230 microM, respectively).
This drug combination may provide a novel approach for cancer treatment.
forrás: http://www.ncbi.nlm.nih.gov/pubmed/11251172
2014-03-11 13:52:27
Artesunate (ART) is a semi-synthetic derivative of artemisinin, the active principle of the Chinese herb Artemisia annua. ART reveals remarkable activity against otherwise multidrugresistant Plasmodium falciparum and P. vivax malaria.
ART has now been analyzed for its anti-cancer activity against 55 cell lines of the Developmental Therapeutics Program of the National Cancer Institute, USA. ART was most active against leukemia and colon cancer cell lines (mean GI50 values: 1.11+/-0.56 microM and 2.13+/-0.74 microM , respectively).
Nonsmall cell lung cancer cell lines showed the highest mean GI50 value (25.62+/-14.95 microM) indicating the lowest sensitivity towards ART in this test panel. Intermediate GI50 values were obtained for melanomas, breast, ovarian, prostate, CNS, and renal cancer cell lines. Importantly, a comparison of ART's cytotoxicity with those of other standard cytostatic drugs showed that ART was active in molar ranges comparable to those of established anti-tumor drugs. Furthermore, we tested CEM leukemia sub-lines resistant to either doxorubicin, vincristine, methotrexate, or hydroxyurea which do not belong to the N.C.I. screening panel. None of these drug-resistant cell lines showed cross resistance to ART. To gain insight into the molecular mechanisms of ART's cytotoxicity, we used a panel of isogenic Saccaromyces cerevisiae strains with defined genetic mutations in DNA repair, DNA checkpoint and cell proliferation genes. A yeast strain with a defective mitosis regulating BUB3 gene showed increased ART sensitivity and another strain with a defective proliferation-regulating CLN2 gene showed increased ART resistance over the wild-type strain, wt644. None of the other DNA repair or DNA check-point deficient isogenic strains were different from the wild-type. These results and the known low toxicity of ART are clues that ART may be a promising novel candidate for cancer chemotherapy.
forrás: http://www.ncbi.nlm.nih.gov/pubmed/19756601
2014-03-11 13:38:18
PURPOSE:
Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, has exhibited thestrongest antimalarial activity among the derivatives of artemisinin. There is growingevidence that DHA has some impact against tumors. Our purpose was to evaluate in vitro antitumoral properties of DHA in the murine Lewis lung carcinoma (LLC) cell line. At thesame time, we observed the therapeutic effect of DHA combined with cyclophosphamide(CTX) in the LLC and combined with cisplatin (CDDP) in the human non-small cell lung cancer A549 xenotransplanted carcinoma in vivo.
METHODS:
Cytotoxicity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidemethod, apoptosis was measured by AO/EB double staining and flow cytometry. Theexpression of vascular endothelial growth factor (VEGF) receptor KDR/flk-1 was analyzed by western blotting and RT-PCR. In vivo activity of DHA combined with CTX or CDDP wasassayed through tumor growth and metastasis.
RESULTS:
Dihydroartemisinin exhibited high anti-cancer activity in LLC cell line. DHA also inducedapoptosis of LLC cells and influenced the expression of VEGF receptor KDR/flk-1.Furthermore, in both tumor xenografts, a greater degree of growth inhibition was achieved when DHA and chemotherapeutics were used in combination. The affection by DHA combined CTX on LLC tumor metastasis was significant.
CONCLUSIONS:
Dihydroartemisinin is a potent compound against LLC cell line in vitro. In vivo, thecombination strategy of DHA and chemotherapeutics holds promise for the treatment ofrelatively large and rapidly growing lung cancers.
