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Micaela Martinez

Bio: Micaela Martinez is an academic researcher from University of California, Irvine. The author has contributed to research in topics: Colorectal cancer & Resveratrol. The author has an hindex of 5, co-authored 6 publications receiving 249 citations.

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Journal ArticleDOI
TL;DR: It is suggested that GP, which contains low dosages of resveratrol in combination with other bioactive components, can inhibit the Wnt pathway in vivo and that this effect is confined to the normal colonic mucosa.
Abstract: CONTEXT Resveratrol exhibits colon cancer prevention activity in animal models; it is purported to have this activity in humans and inhibit a key signaling pathway involved in colon cancer initiation, the Wnt pathway, in vitro. DESIGN A phase I pilot study in patients with colon cancer was performed to evaluate the effects of a low dose of plant-derived resveratrol formulation and resveratrol-containing freeze-dried grape powder (GP) on Wnt signaling in the colon. Eight patients were enrolled and normal colonic mucosa and colon cancer tissue were evaluated by Wnt pathway-specific microarray and quantitative real-time polymerase chain reaction (qRT-PCR) pre- and post-exposure to resveratrol/GP. RESULTS Based on the expression of a panel of Wnt target genes, resveratrol/GP did not inhibit the Wnt pathway in colon cancer but had significant (p < 0.03) activity in inhibiting Wnt target gene expression in normal colonic mucosa. The greatest effect on Wnt target gene expression was seen following ingestion of 80 g of GP per day (p < 0.001). These results were confirmed with qRT-PCR of cyclinD1 and axinII. The inhibitory effect of GP on Wnt signal throughput was confirmed in vitro with a normal colonic mucosa-derived cell line. CONCLUSIONS These data suggest that GP, which contains low dosages of resveratrol in combination with other bioactive components, can inhibit the Wnt pathway in vivo and that this effect is confined to the normal colonic mucosa. Further study of dietary supplementation with resveratrol-containing foods such as whole grapes or GP as a potential colon cancer preventive strategy is warranted. TRIAL REGISTRATION NCT00256334.

207 citations

Journal ArticleDOI
TL;DR: Dkk3 gene expression is frequently downregulated in endometrial cancer, and is associated with poor prognostic clinicopathologic markers, which may prove to be important in the design of novel biomarkers and treatment modalities for advanced EC.

37 citations

Journal ArticleDOI
TL;DR: The reduction in Wnt signaling and mucosal proliferation seen following short-term ingestion of 1/3–1 lb (0.15–0.45 kg) of grapes per day may reduce the risk of mutational events that can facilitate colon carcinogenesis.
Abstract: A diet rich in fruits and vegetables, and a grape-derived compound, resveratrol, have been linked to a reduced incidence of colon cancer. In vitro and in vivo, resveratrol suppresses Wnt signaling, a pathway constitutively activated in over 85 % of colon cancers. Thirty participants were placed on a low resveratrol diet and subsequently allocated to one of three groups ingesting 1/3-to-1 lb (0.15–0.45 kg) of grapes per day for 2 weeks. Dietary information was collected via 24-h recall. Colon biopsies for biomarker analysis were obtained pre- and post-grape and evaluated for the expression of Wnt pathway target genes and for markers of proliferation by RT-PCR and immunohistochemistry. Participants lost an average of 2 · 6 lb (1.2 kg, p = 0 · 0018) during the period of grape ingestion. The expression of CyclinD1 (p < 0 · 01), AXIN2, CD133 (p = 0 · 02) and Ki67 (p = 0 · 002) were all reduced after grape ingestion. Individuals over 50 years of age and those with high dietary arginine consumption had increased basal expression of CyclinD1, AXIN2, cMYC and CD133 (p value range 0 · 04 to <0 · 001) that, following grape ingestion, were reduced to levels seen in younger participants. The reduction in Wnt signaling and mucosal proliferation seen following short-term ingestion of 1/3–1 lb (0.15–0.45 kg) of grapes per day may reduce the risk of mutational events that can facilitate colon carcinogenesis. The potential benefit is most marked for high-risk older individuals and individuals whose diet is high in arginine intake. Dietary grape supplementation may play a role in colon cancer prevention for high-risk individuals.

21 citations

Journal ArticleDOI
TL;DR: Resveratrol, a stilbene found in the skin of grapes and wine, inhibits Wnt signaling in vitro and is purported to have colon cancer prevention activity.
Abstract: 3622 Background: Resveratrol (Res), a stilbene found in the skin of grapes and wine, inhibits Wnt signaling in vitro and is purported to have colon cancer prevention activity. Methods: We conducted...

7 citations

Journal ArticleDOI
TL;DR: A clinical trial was initiated in patients receiving chemotherapy for metastatic colorectal cancer to determine if administration of GM-CSF in this setting was immunostimulatory.
Abstract: Background: Advanced cancer and chemotherapy are both associated with immune system suppression. We initiated a clinical trial in patients receiving chemotherapy for metastatic colorectal cancer to determine if administration of GM-CSF in this setting was immunostimulatory.

7 citations


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TL;DR: Adjunctive RT in early stage intermediate risk endometrial carcinoma decreases the risk of recurrence, but should be limited to patients whose risk factors fit a high intermediate risk definition.
Abstract: Between June 1987 and July 1995, 448 women with endometrial cancer were enrolled in a prospective, randomized trial comparing the use of postoperative radiation versus no postoperative treatment. Participants had stage IB, IC, II, or IIB endometrial adenocarcinoma with an intermediate risk of recurrence (that is, tumor with any degree of myometrial invasion, adenocarcinoma of any grade, and no evidence of lymph node involvement). In addition, an analysis was performed of 2 subgroups. High-risk patients had all of these risk factors: moderate to poorly differentiated tumor, presence of lymphvascular invasion, and myometrial invasion to the outer third; they were 50 years of age or older with 2 of the 3 risk factors; or they were 70 years of age or older and had one additional risk factor. Women who did not qualify for the high-risk subgroup were considered in the low-risk subgroup. Three hundred ninety-two participants met all eligibility requirements for inclusion in the analysis. Two hundred two women were randomized to the whole pelvic radiation group, and 190 received no additional postoperative treatment. Otherwise, both groups had similar clinical and demographic characteristics. In the radiation therapy (RT) group, 13 patients refused postoperative treatment and 5 received less than the prescribed dose. In the no-treatment group, 2 patients received fall-dose postoperative RT. Twenty-four participants were lost to follow up within a median of 50 months. Overall median follow up was 68 months. Forty-four patients, 31 in the unirradiated group and 13 in the radiation group, developed disease recurrence. After a median follow up of 80 months, 15 of the women who recurred were alive with disease. In all, 66 women in the study died, 32 from disease or treatment-related causes. Women who received postoperative radiation therapy were less likely to have a recurrence of disease than those who had no additional treatment Among the 202 patients who had no postoperative treatment, 13 recurred in the vagina, 4 in the pelvis, 1 in the vagina and pelvis, and 13 had distant recurrences. In the RT group, 2 women, both of whom refused treatment with radiation, had a recurrence in the vagina. One other patient recurred in the vagina and pelvis, and 10 had distant recurrences. Patients who were treated with postoperative radiation therapy had a 58% lower risk of ever having a recurrence of disease than women who did not. The overall risk of recurrence in the first 24 months after treatment was 3% (90% confidence interval [CI], 0.02-0.06) for women who received RT and 12% (90% CI, 0.09-0.17) for women who had no additional treatment. The estimated cumulative risk of recurring in the vagina or pelvis within the first 24 months was 1.6% (90% CI, 0.6-3.9) for those in the RT group compared with 7.4% (90% CI, 4.9-11.0) for the no additional treatment group. In the 132 women who were in the high-risk subgroup, 28 (28 of 44; 64%) had a recurrence of disease and 22 died from disease (22 of 32; 67%). The estimated risk of recurrence for high-risk women was 0.46 (90% CI, 0.19-1.11) compared with 0.42 (90% CI, 0.21-0.83) for low-risk women. There were 2 deaths from intestinal injury associated with radiation treatrnent. Overall, there were 6 instances of bowel obstruction in the RT group and 1 in the no additional treatment group.

624 citations

Journal ArticleDOI
TL;DR: The current state of knowledge on the effects of resveratrol on humans is examined to utilize this information to develop further guidelines for the implementation of human clinical trials.
Abstract: In the past decade, the small polyphenol resveratrol has received widespread attention as either a potential therapy or as a preventive agent for numerous diseases. Studies using purified enzymes, cultured cells, and laboratory animals have suggested that resveratrol has anti-aging, anti-carcinogenic, anti-inflammatory, and anti-oxidant properties that might be relevant to chronic diseases and/or longevity in humans. Although the supporting research in laboratory models is quite substantial, only recently data has emerged to describe the effects of resveratrol supplementation on physiological responses in humans. The limited number of human clinical trials that are available has largely described various aspects of resveratrol's safety and bioavailability, reaching a consensus that it is generally well-tolerated, but have poor bioavailability. Very few published human studies have explored the ability of resveratrol to achieve the physiological benefits that have been observed in laboratory models, although many clinical trials have recently been initiated. This review aims to examine the current state of knowledge on the effects of resveratrol on humans and to utilize this information to develop further guidelines for the implementation of human clinical trials.

506 citations

Journal ArticleDOI
TL;DR: The current focus of this review is resveratrol’s in vivo and in vitro effects in a variety of cancers, and intracellular molecular targets modulated by this polyphenol.
Abstract: Natural product compounds have recently attracted significant attention from the scientific community for their potent effects against inflammation-driven diseases, including cancer. A significant amount of research, including preclinical, clinical, and epidemiological studies, has indicated that dietary consumption of polyphenols, found at high levels in cereals, pulses, vegetables, and fruits, may prevent the evolution of an array of diseases, including cancer. Cancer development is a carefully orchestrated progression where normal cells acquires mutations in their genetic makeup, which cause the cells to continuously grow, colonize, and metastasize to other organs such as the liver, lungs, colon, and brain. Compounds that modulate these oncogenic processes can be considered as potential anti-cancer agents that may ultimately make it to clinical application. Resveratrol, a natural stilbene and a non-flavonoid polyphenol, is a phytoestrogen that possesses anti-oxidant, anti-inflammatory, cardioprotective, and anti-cancer properties. It has been reported that resveratrol can reverse multidrug resistance in cancer cells, and, when used in combination with clinically used drugs, it can sensitize cancer cells to standard chemotherapeutic agents. Several novel analogs of resveratrol have been developed with improved anti-cancer activity, bioavailability, and pharmacokinetic profile. The current focus of this review is resveratrol's in vivo and in vitro effects in a variety of cancers, and intracellular molecular targets modulated by this polyphenol. This is also accompanied by a comprehensive update of the various clinical trials that have demonstrated it to be a promising therapeutic and chemopreventive agent.

459 citations

Journal ArticleDOI
TL;DR: Natural compounds found to inhibit one or more pathways that contribute to proliferation have been found and will be very important for identifying signaling pathways and molecular targets that may provide early diagnostic markers and/or critical targets for the development of new drugs or drug combinations that block tumor formation and progression.

429 citations

Journal ArticleDOI
TL;DR: This review highlights the in vivo effects of resveratrol treatment on breast, colorectal, liver, pancreatic, and prostate cancers and suggests that many factors need to be considered before resver atrol can be used for human cancer prevention or therapy.
Abstract: Resveratrol is a naturally occurring polyphenol that provides a number of anti-aging health benefits including improved metabolism, cardioprotection, and cancer prevention. Much of the work on resveratrol and cancer comes from in vitro studies looking at resveratrol actions on cancer cells and pathways. There are, however, comparatively fewer studies that have investigated resveratrol treatment and cancer outcomes in vivo, perhaps limited by its poor bioavailability when taken orally. Although research in cell culture has shown promising and positive effects of resveratrol, evidence from rodents and humans is inconsistent. This review highlights the in vivo effects of resveratrol treatment on breast, colorectal, liver, pancreatic, and prostate cancers. Resveratrol supplementation in animal models of cancer has shown positive, neutral as well as negative outcomes depending on resveratrol route of administration, dose, tumor model, species, and other factors. Within a specific cancer type, there is variability between studies with respect to strain, age, and sex of animal used, timing and method of resveratrol supplementation, and dose of resveratrol used to study cancer endpoints. Together, the data suggest that many factors need to be considered before resveratrol can be used for human cancer prevention or therapy.

422 citations