Publications by authors named "Muindi J"

Background: Several studies have suggested that low 25(OH) vitamin D3 levels may be prognostic in some malignancies, but no studies have evaluated their impact on treatment outcome in patients with acute myeloid leukemia (AML).

Methods: Vitamin D levels were evaluated in 97 consecutive, newly diagnosed, intensively treated patients with AML. MicroRNA expression profiles and single nucleotide polymorphisms (SNPs) in the 25(OH) vitamin D3 pathway genes were evaluated and correlated with 25(OH) vitamin D3 levels and treatment outcome.

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Cholecalciferol (D(3)) supplementation results in variable increases in serum 25(OH)D(3) levels, however, the influence of genetic polymorphisms on these variable responses is unclear. We measured serum 25(OH)D(3), 24,25(OH)(2)D(3), 1,25(OH)2D(3) and VDBP levels in 50 colorectal cancer (CRC) patients before and during 2,000 IU daily oral D(3) supplementation for six months and in 263 archived CRC serum samples. Serum PTH levels and PBMC 24-OHase activity were also measured during D(3) supplementation.

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Background: Preclinical studies demonstrated antiproliferative synergy of 1,25-D3 (calcitriol) with cisplatin. The goals of this phase I/II study were to determine the recommended phase II dose (RP2D) of 1,25-D3 with cisplatin and docetaxel and its efficacy in metastatic non-small-cell lung cancer.

Methods: Patients were ≥18 years, PS 0-1 with normal organ function.

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Background: We have previously reported a negative correlation between the effect of chemotherapy and 25-hydroxy vitamin D(3) (25-D(3)) levels in patients with colorectal cancer. Based on this finding, we hypothesized that the response to vitamin D(3) supplementation may be attenuated in patients with colorectal cancer.

Aim: To determine 25-D(3) response to 2000 IU/day vitamin D(3) supplementation in patients with colorectal cancer.

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Background: Vorinostat is synergistic with 5-FU in vitro and in vivo models. A combination of these two agents was associated with clinical activity in 5-FU refractory colorectal cancer patients in a phase I clinical trial, therefore warranting the conduct of this prospective phase II study.

Patients And Methods: Patients with refractory metastatic colorectal cancer were randomized in a two-stage design to receive vorinostat at 800 or 1,400 mg/day once a day × 3, every 2 weeks.

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Background: Epidemiologic data suggest that there is an association between vitamin D deficiency and influenza infection. We conducted a prospective influenza vaccination study to determine the influence of vitamin D status on serological response to influenza vaccine in prostate cancer (CaP) patients.

Methods: During the 2006-2007 influenza season, CaP patients treated at Roswell Park Cancer Institute were offered vaccination with the trivalent influenza vaccine (Fluzone®, 2006-2007) and sera collected for hemagglutination inhibition (HI) assay titers before and 3 months after vaccination.

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Gemcitabine is the standard care chemotherapeutic agent to treat pancreatic cancer. Previously we demonstrated that calcitriol (1, 25-dihydroxycholecalciferol) has significant anti-proliferative effects in vitro and in vivo in multiple tumor models and enhances the activity of a variety of chemotherapeutic agents. We therefore investigated whether calcitriol could potentiate the cytotoxic activity of gemcitabine in the human pancreatic cancer Capan-1 model system.

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High systemic exposures to calcitriol are necessary for optimal antitumor effects. Human prostate cancer PC3 cells are insensitive to calcitriol treatment. Therefore, we investigated whether the inhibition of 24-hydroxylase (CYP24A1), the major calcitriol inactivating enzyme, by ketoconazole (KTZ) or RC2204 modulates calcitriol serum pharmacokinetics and biologic effects.

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Calcitriol, a regulator of calcium homeostasis with antitumor properties, is degraded by the product of the CYP24A1 gene, which is downregulated in human prostate cancer by unknown mechanisms. We found that CYP24A1 expression is inversely correlated with promoter DNA methylation in prostate cancer cell lines. Treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (DAC) activates CYP24A1 expression in prostate cancer cells.

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Purpose: We conducted a phase I clinical trial to determine the maximum tolerated dose (MTD) of daily or twice daily vorinostat x 3 days when combined with fixed doses of 5-fluorouracil (FU) and leucovorin every 2 weeks.

Experimental Design: Vorinostat doses were escalated in a standard 3 x 3 phase I design. FU/leucovorin was started on day 2 of vorinostat and consisted of leucovorin 400 mg/m(2) i.

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Purpose: High-dose calcitriol (1,25-dihydroxyvitamin D(3)) has antineoplastic activity against a range of tumors and potentiates chemotherapeutic agents. In an earlier canine study, the MTD of intravenous (i.v.

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Purpose: The primary objective of this study was to determine the maximum tolerated dose (MTD) of intravenously (i.v.) calcitriol administered in combination with a fixed oral dose of dexamethasone and gefitinib in patients with refractory solid tumors.

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The epidemiology of serogroup X meningococcal meningitis in Africa is unknown. During a serogroup X meningococcus outbreak in Kenya, case finding involved record review at health facilities and interviews with health workers and community leaders in West Pokot district. An age- and location-matched case-control study for risk factors was done.

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Background: Preclinical and clinical evidence support an association between vitamin D deficiency and an increased risk of colorectal cancer. Normal vitamin D status has been linked to favorable health outcomes ranging from decreased risk of osteoporosis to improved cancer mortality. We performed a retrospective study to assess the impact of metastatic disease and chemotherapy treatment on vitamin D status in patients with colorectal cancer residing in Western New York.

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Purpose: Calcitriol potentiates cisplatin-mediated activity in a variety of tumor models. We examine here, the effect of calcitriol and cisplatin pre-clinically and clinically in canine spontaneous tumors through in vitro studies on tumor cells and through a phase I study of calcitriol and cisplatin to identify the maximum-tolerated dosage (MTD) of this combination in dogs with cancer and to characterize the pharmacokinetic disposition of calcitriol in dogs.

Methods: Canine tumor cells were investigated for calcitriol/cisplatin interactions on proliferation using an MTT assay in a median-dose effect analysis; data were used to derive a combination index (CI).

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Retinoids promote lung alveolarization in animal models and were administered to patients as part of the Feasibility of Retinoid Therapy for Emphysema (FORTE) study. This FORTE substudy investigated the pharmacokinetic profiles of 2 retinoic acid isomers-all-trans-retinoic acid (ATRA) and 13-cis-retinoic acid (13-cRA)-in subjects with emphysema, evaluated strategies to overcome self-induced ATRA catabolism, and identified pharmacodynamic relationships. Comprehensive and limited pharmacokinetics were obtained at multiple visits in emphysema subjects treated with placebo (n = 30), intermittent dosing (4 days/week) with low-dose ATRA (1 mg/kg/day, n = 21), or high-dose ATRA (2 mg/kg/day, n = 25) or daily administration of 13-cRA (1 mg/kg/day, n = 40).

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24-Hydroxylase (CYP24) activity modulates in vitro and in vivo calcitriol metabolism and biologic effects. We have investigated, in human PC3, DU145 and LNCaP prostate cancer cell lines, the relationship of CYP24 single nucleotide polymorphisms (SNPs) and splicing and the variable patterns of baseline and calcitriol-inducible CYP24 activity. DU145 cells exhibit baseline CYP24 activity that is further induced by calcitriol.

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Purpose: In preclinical models, calcitriol and the tyrosine kinase inhibitor gefitinib are synergistic and modulate extracellular signal-regulated kinase (Erk) and Akt pathways. Therefore, we conducted a phase I study of calcitriol and gefitinib to determine the maximum tolerated dose (MTD) of this combination.

Experimental Design: Calcitriol was given i.

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Calcitriol (1,25-dihydroxycholecalciferol), the most active form of vitamin D, has selective anti-proliferative effects on tumor-derived endothelial cells (TDEC) compared with Matrigel-derived endothelial cells (MDEC). Although both cell types have an intact vitamin D receptor-signaling axis, this study demonstrates that upon treatment with calcitriol, 24-hydroxylase (CYP24) mRNA, protein and enzymatic activity were markedly induced in MDEC in a time-dependent manner but not in TDEC. Furthermore, treatment of MDEC with a CYP24 small interfering RNA restored sensitivity to calcitriol.

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Background: Retinoids promote alveolar septation in the developing lung and stimulate alveolar repair in some animal models of emphysema.

Methods: One hundred forty-eight subjects with moderate-to-severe COPD and a primary component of emphysema, defined by diffusing capacity of the lung for carbon monoxide (Dlco) [37.1 +/- 12.

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While 1,25 dihydroxycholecalciferol (calcitriol) is best recognized for its effects on bone and mineral metabolism, epidemiological data indicate that low vitamin D levels may play a role in the genesis and progression of breast, lung, colorectal and prostate cancer, as well as malignant lymphoma and melanoma. Calcitriol has strong antiproliferative effects in prostate, breast, colorectal, head/neck and lung cancer, as well as lymphoma, leukemia and myeloma model systems. Antiproliferative effects are seen in vitro and in vivo.

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Studies in our laboratory demonstrate that vitamin D (1,25 dihydroxycholecalciferol or calcitriol) has significant antitumor activity in vitro and in vivo in murine and human squamous cell, prostate, lung, pancreatic and myeloma model systems. Calcitriol induces G0/G1 arrest, modulates p27 and p21, the cyclin-dependent kinase (cdk) inhibitors implicated in G1 arrest, and induces cleavage of caspase 3, PARP and the mitogen-activated protein kinase (MEK) in a caspase-dependent manner. Calcitriol also decreases phospho-Erk (P-Erk) and phospho-Akt (P-Akt), kinases that regulate cell survival pathways and up-regulate the pro-apoptotic signaling molecule, MEKK-1.

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Purpose: To determine, in peripheral blood monocytes (PBM), whether the enzymatic activities of fructose 1,6-bisphosphatase (FBPase), cytidine deaminase (CDDase) and 24-hydroxylase (CYP24), enzymes regulated by calcitriol are useful pharmacodynamic (PD) measures of calcitriol effects in cancer patients.

Methods: Cancer patients enrolled in a phase I clinical trial of calcitriol and carboplatin were studied. Baseline and calcitriol-induced changes in FBPase, CDDase and CYP24 activities were measured in PBM collected before, 6, 24, and 48 h after administration of calcitriol, prior to carboplatin, in doses ranging from 4 to 11 mug daily for 3 consecutive days (QDx3).

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Background: Data suggest that vitamin D plays a role in the treatment and prevention of prostate cancer. The combination of high-dose, intermittent calcitriol (1,25 dihydroxyvitamin D3) plus dexamethasone was studied based on evidence that dexamethasone potentiates the antitumor effects of calcitriol and ameliorates hypercalcemia.

Methods: Oral calcitriol was administered weekly, Monday, Tuesday, and Wednesday (MTW), at a dose of 8 microg, for 1 month, at a dose of 10 microg every MTW for 1 month, and at a dose of 12 microg every MTW thereafter.

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Tacrolimus (Prograf, FK506, Fujisawa Healthcare) is a widely used immunosuppressive agent that is used both for the prevention and treatment of solid organ transplant rejection as well as for the prevention and treatment of graft-versus-host disease after allogeneic blood and marrow transplant. Oral preparations of tacrolimus are commercially available in 0.5, 1 and 5 mg gelatin capsules.

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