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1.
Int J Mol Sci ; 22(20)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34681684

RESUMO

Adenomatous polyps are precancerous lesions associated with a higher risk of colorectal cancer (CRC). Curcumin and anthocyanins have shown promising CRC-preventive activity in preclinical and epidemiological studies. The objective of this window-of-opportunity, proof-of principle trial was to evaluate the effect of curcumin combined with anthocyanin supplements on tissue biomarkers of colorectal adenomatous polyps. Eligible patients received either anthocyanin and curcumin supplementation or related matching placebo for 4-6 weeks before polyp removal. Adenomatous polyps and adjacent tissue biopsies were collected at baseline and after supplementation for immunohistochemical assessment of ß-catenin, NF-kappa B (NF-κB), Ki-67, P53, and dysplasia. No differences were observed in baseline biomarker expression between normal and dysplastic tissues. The combination of anthocyanins and curcumin resulted in a significant borderline reduction of NF-κB immunohistochemistry (IHC) expression in adenoma tissue (geometric mean ratio (GMR): 0.72; 95% confidence interval (CI): 0.51-1.00; p-value: 0.05) and a trend to a reduction of Ki-67 (GMR: 0.73; 95% CI: 0.50-1.08; p-value: 0.11). No significant modulation of biomarkers in normal adjacent mucosa was observed. We concluded that the combined supplementation of anthocyanins and curcumin seems to lead to a potentially favorable modulation of tissue biomarkers of inflammation and proliferation in colon adenomas.


Assuntos
Pólipos Adenomatosos/prevenção & controle , Antocianinas/farmacologia , Neoplasias Colorretais/prevenção & controle , Curcumina/farmacologia , Suplementos Nutricionais , Pólipos Adenomatosos/genética , Pólipos Adenomatosos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Antígeno Ki-67/genética , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Proteína Supressora de Tumor p53/genética
2.
Cancer Prev Res (Phila) ; 12(3): 123-124, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30700438

RESUMO

A recent article published in The Lancet reports on the seAFOod trial, in which patients with colorectal adenomas received aspirin and/or eicosapentaenoic acid (EPA, an omega-3 polyunsaturated fatty acid) post-resection. The article's abstract indicates that the primary trial endpoint, adenoma detection rate, is negative, but it does not give any indication of the remarkable secondary endpoint (adenoma number) results, which strongly suggest chemopreventive efficacy of both agents. Given the difficulty researchers and physician-scientists experience in staying abreast of the latest literature in the field, inclusion of secondary findings in abstracts should be strongly considered.


Assuntos
Adenoma , Neoplasias Colorretais , Ácidos Graxos Ômega-3 , Aspirina , Método Duplo-Cego , Ácido Eicosapentaenoico , Humanos
3.
Cancer Prev Res (Phila) ; 10(6): 363-370, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28400479

RESUMO

Epidemiologic data support an inverse association between green tea intake and breast cancer risk. Greenselect Phytosome (GSP) is a lecithin formulation of a caffeine-free green tea catechin extract. The purpose of the study was to determine the tissue distribution of epigallocatechin-3-O-gallate (EGCG) and its effect on cell proliferation and circulating biomarkers in breast cancer patients. Twelve early breast cancer patients received GSP 300 mg, equivalent to 44.9 mg of EGCG, daily for 4 weeks prior to surgery. The EGCG levels were measured before (free) and after (total) enzymatic hydrolysis by HPLC-MS/MS in plasma, urine, breast cancer tissue, and surrounding normal breast tissue. Fasting blood samples were taken at baseline, before the last administration, and 2 hours later. Repeated administration of GSP achieved levels of total EGCG ranging from 17 to 121 ng/mL in plasma. Despite a high between-subject variability, total EGCG was detectable in all tumor tissue samples collected up to 8 ng/g. Median total EGCG concentration was higher in the tumor as compared with the adjacent normal tissue (3.18 ng/g vs. 0 ng/g, P = 0.02). Free EGCG concentrations ranged from 8 to 65.8 ng/mL in plasma (P between last administration and 2 hours after <0.001). Free EGCG plasma levels showed a significant positive correlation with the Ki-67 decrease in tumor tissue (P = 0.02). No change in any other biomarkers was noted, except for a slight increase in testosterone levels after treatment. Oral GSP increases bioavailability of EGCG, which is detectable in breast tumor tissue and is associated with antiproliferative effects on breast cancer tissue. Cancer Prev Res; 10(6); 363-9. ©2017 AACR.


Assuntos
Anticarcinógenos/farmacocinética , Neoplasias da Mama/terapia , Camellia sinensis/química , Catequina/análogos & derivados , Extratos Vegetais/farmacocinética , Administração Oral , Anticarcinógenos/uso terapêutico , Disponibilidade Biológica , Biomarcadores Tumorais/sangue , Biópsia , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/sangue , Catequina/farmacocinética , Catequina/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Hidrólise , Lecitinas/química , Mastectomia , Pessoa de Meia-Idade , Projetos Piloto , Extratos Vegetais/uso terapêutico , Espectrometria de Massas em Tandem , Testosterona/sangue , Distribuição Tecidual
4.
Clin Cancer Res ; 22(17): 4322-7, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27220959

RESUMO

At several recent, internationally attended scientific meetings, including the American Association for Cancer Research (AACR)'s "Shaping the Future of Cancer Prevention: A Roadmap for Integrative Cancer Science and Public Health" summit in Leesburg (VA) and the AACR Annual Meeting in New Orleans, the focus on cancer prevention to reduce cancer-related deaths was extensively discussed with renewed attention and emphasis. Cancer prevention should be actively proposed even to healthy individuals, and not just to individuals with high cancer risk. We discuss evaluation of a high cancer risk versus the relatively low risk for side effects of chemopreventive agents. The concept of cancer interception, which is halting transformed cells from becoming malignant cancers, should be adopted for cancer prevention. Potential prevention/interception actions include adopting healthy life style and avoiding carcinogens, repressing inflammation and pathologic angiogenesis, controlling metabolism, correcting insulin resistance and other metabolic alterations. Current drugs with limited toxicity can be repurposed to reduce cancer incidence. Aspirin is now being recommended for the prevention of colorectal cancer and it prevents other neoplasms as well. Metformin and ß-blockers could be valuable for reducing pancreatic and breast cancer onset. On the basis of the evaluation of cancer risk, we here call for personalized approaches for cancer prevention and preventive interception and we envisage a list of measures and potential guidelines for preventive and interceptive strategies to reduce cancer burden. Investment into translational research to bring these approaches into public health policies and in the clinic is urgently needed. Clin Cancer Res; 22(17); 4322-7. ©2016 AACR.


Assuntos
Anticarcinógenos/uso terapêutico , Quimioprevenção , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Anticarcinógenos/farmacologia , Quimioprevenção/métodos , Humanos , Neoplasias/epidemiologia , Neoplasias/etiologia
5.
Breast Cancer Res Treat ; 144(2): 321-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24487691

RESUMO

The purpose of the study is to determine the effects of the BIG 1-98 treatments on bone mineral density. BIG 1-98 compared 5-year adjuvant hormone therapy in postmenopausal women allocated to four groups: tamoxifen (T); letrozole (L); 2-years T, 3-years L (TL); and 2-years L, 3-years T (LT). Bone mineral density T-score was measured prospectively annually by dual energy X-ray absorption in 424 patients enrolled in a sub-study after 3 (n = 150), 4 (n = 200), and 5 years (n = 74) from randomization, and 1 year after treatment cessation. Prevalence of osteoporosis and the association of C-telopeptide, osteocalcin, and bone alkaline phosphatase with T-scores were assessed. At 3 years, T had the highest and TL the lowest T-score. All arms except for LT showed a decline up to 5 years, with TL exhibiting the greatest. At 5 years, there were significant differences on lumbar T-score only between T and TL, whereas for femur T-score, differences were significant for T versus L or TL, and L versus LT. The 5-year prevalence of spine and femur osteoporosis was the highest on TL (14.5 %, 7.1 %) then L (4.3 %, 5.1 %), LT (4.2 %, 1.4 %) and T (4 %, 0). C-telopeptide and osteocalcin were significantly associated with T-scores. While adjuvant L increases bone mineral density loss compared with T, the sequence LT has an acceptable bone safety profile. C-telopeptide and osteocalcin are useful markers of bone density that may be used to monitor bone health during treatment. The sequence LT may be a valid treatment option in patients with low and intermediate risk of recurrence.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Biomarcadores Tumorais/sangue , Densidade Óssea/efeitos dos fármacos , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Nitrilas/administração & dosagem , Tamoxifeno/administração & dosagem , Triazóis/administração & dosagem , Idoso , Fosfatase Alcalina/sangue , Quimioterapia Adjuvante/métodos , Colágeno Tipo I/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteoporose Pós-Menopausa/sangue , Peptídeos/sangue , Pós-Menopausa/sangue , Estudos Prospectivos
6.
Breast Cancer Res ; 14(5): 214, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23106852

RESUMO

Tamoxifen is a drug that has been in worldwide use for the treatment of estrogen receptor (ER)-positive breast cancer for over 30 years; it has been used in both the metastatic and adjuvant settings. Tamoxifen's approval for breast cancer risk reduction dates back to 1998, after results from the Breast Cancer Prevention Trial, co-sponsored by the National Cancer Institute and the National Surgical Adjuvant Breast and Bowel Project, showed a 49% reduction in the incidence of invasive, ER-positive breast cancer in high-risk women. Despite these positive findings, however, the public's attitude toward breast cancer chemoprevention remains ambivalent, and the toxicities associated with tamoxifen, particularly endometrial cancer and thromboembolic events, have hampered the drug's uptake by high-risk women who should benefit from its preventive effects. Among the strategies to overcome such obstacles to preventive tamoxifen, two novel and potentially safer modes of delivery of this agent are discussed in this paper. Low-dose tamoxifen, expected to confer fewer adverse events, is being investigated in both clinical biomarker-based trials and observational studies. A series of systemic biomarkers (including lipid and insulin-like growth factor levels) and tissue biomarkers (including Ki-67) are known to be favorably affected by conventional tamoxifen dosing and have been shown to be modulated in a direction consistent with a putative anti-cancer effect. These findings suggest possible beneficial clinical preventive effects by low-dose tamoxifen regimens and they are supported by observational studies. An alternative approach is topical administration of active tamoxifen metabolites directly onto the breast, the site where the cancer is to be prevented. Avoidance of systemic administration is expected to reduce the distribution of drug to tissues susceptible to tamoxifen-induced toxicity. Clinical trials of topical tamoxifen with biological endpoints are still ongoing whereas pharmacokinetic studies have already shown that appropriate formulations of drug successfully penetrate the skin to reach breast tissue, where a preventive effect is sought.


Assuntos
Neoplasias da Mama/prevenção & controle , Quimioprevenção , Moduladores Seletivos de Receptor Estrogênico/administração & dosagem , Tamoxifeno/administração & dosagem , Administração Oral , Administração Tópica , Animais , Neoplasias da Mama/metabolismo , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos
7.
Breast ; 20 Suppl 3: S36-41, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22015291

RESUMO

This review highlights the role of vitamins and natural compounds in breast cancer prevention, with a particular focus on Vitamin D. In the last decades, both encouraging and discouraging results about the association between antioxidant supplementation and cancer have been reported to public and scientific community. Their safe and favorable toxicity profile makes them suitable to be investigated in a preventive setting. However, a recent large meta-analysis showed that treatment with beta carotene, vitamin A, and vitamin E may increase mortality, whereas the potential roles of vitamin C and selenium on mortality need further study. Likewise, folate levels were not associated with reduced breast cancer risk in a recent meta-analysis. Several studies have shown that a high proportion of women at-risk for breast cancer or affected by the disease have deficient vitamin D levels, i.e., 250 H-D <20 ng/ml or 50 nmol/L. While the association between Vitamin D levels and breast cancer risk/prognosis is still controversial, the U-shaped relationship between 250 H-D levels observed in different studies suggests the need to avoid both deficient and too high levels. Further trials using an optimal dose range are needed to assess the preventive and therapeutic effect of vitamin D. Finally, Fenretinide, a pro-apoptotic and pro-oxidant vitamin A derivative, has shown promise in several trials and its preventive potential is being assessed in young women at very high risk for breast cancer.


Assuntos
Antioxidantes/uso terapêutico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/prevenção & controle , Quimioprevenção/métodos , Vitaminas/uso terapêutico , Suplementos Nutricionais , Medicina Baseada em Evidências , Feminino , Ácido Fólico/uso terapêutico , Humanos , Prevenção Primária/métodos , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento , Vitamina D/uso terapêutico , Vitamina E/uso terapêutico
8.
Breast Cancer Res Treat ; 114(3): 599-605, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18465220

RESUMO

Several independent studies have presented evidence for the involvement of human papillomaviruses (HPV) in the aetiology of human breast cancer, while others have reported the opposite findings. Here, we have analysed by a high sensitive multiplex PCR-based method the prevalence of alpha mucosal and beta cutaneous HPV DNA in 90 ductal lavages, colostrum and milk. Ten of the 70 DLs analyzed (14%) contained a single or multiple beta HPV types, while DNA from mucosal high-risk HPV types was detected in only one sample (1/70). A strong reduction of HPV positivity in DL fluids was observed in 45 specimens collected after removal of the superficial layers of the nipple epidermis. All DLs were negative for the mucosal low-risk HPV types 6 and 11. Finally, HPV positivity was low in colostrum and milk. Our data show that DNA of alpha mucosa and beta cutaneous HPV types are rarely present in the breast fluids and suggest that a direct role of HPV in breast carcinogenesis is unlikely.


Assuntos
Líquidos Corporais/virologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/virologia , Colostro/virologia , Leite Humano/virologia , Papillomaviridae/metabolismo , Infecções por Papillomavirus/virologia , Adulto , Idoso , DNA Viral/metabolismo , Feminino , Humanos , Glândulas Mamárias Humanas/virologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/metabolismo , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
9.
Clin Cancer Res ; 10(13): 4389-97, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15240527

RESUMO

PURPOSE: Oral conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA) increase breast cancer risk, whereas the effect of transdermal estradiol (E2) and MPA is less known. Fenretinide may decrease second breast malignancies in premenopausal women but not in postmenopausal women, suggesting a hormone-sensitizing effect. We compared the 6 and 12-month changes in insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), IGF-I:IGFBP-3 ratio, sex-hormone binding-globulin, and computerized mammographic percent density during oral CEE or transdermal E2 with sequential MPA and fenretinide or placebo. EXPERIMENTAL DESIGN: A total of 226 recent postmenopausal healthy women were randomly assigned in a two-by-two factorial design to either oral CEE 0.625 mg/day (n = 111) or transdermal E2, 50 microg/day (n = 115) and to fenretinide 100 mg/twice a day (n = 112) or placebo (n = 114) for 12 months. Treatment effects were investigated by the Kruskall-Wallis test and analysis of covariance. P values were two-sided. RESULTS: After 12 months, oral CEE decreased IGF-I by 26% [95% confidence interval (CI), 22-30%] and increased sex-hormone binding-globulin by 96% (95% CI, 79-112%) relative to baseline, whereas no change occurred with transdermal E2 (P < 0.001 between groups). Fenretinide decreased IGFBP-3 relative to placebo (P = 0.04). Percentage of breast density showed an absolute increase of 3.5% (95% CI, 2.5-4.6%) during hormone therapy without differences between groups (P = 0.39). CONCLUSIONS: Oral CEE has more favorable changes than transdermal E2 on circulating breast cancer risk biomarkers but gives similar effects on mammographic density. Fenretinide exerted little modulation on most biomarkers. The clinical implications of these findings require additional studies.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Estrogênios/administração & dosagem , Fenretinida/administração & dosagem , Administração Cutânea , Administração Oral , Adulto , Amenorreia/metabolismo , Regulação para Baixo , Ácido Edético/farmacologia , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Mamografia , Pessoa de Meia-Idade , Placebos , Pós-Menopausa , Projetos de Pesquisa , Risco , Globulina de Ligação a Hormônio Sexual/metabolismo , Fatores de Tempo
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