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Eddie Reed

Publications and source records attributed to Eddie Reed.

52 records · Page 3Linked to original sources
PubMed2003

Phase II trial of carboxyamidotriazole in patients with relapsed epithelial ovarian cancer.

PURPOSE: Carboxyamidotriazole (CAI) is a cytostatic inhibitor of nonvoltage-operated calcium channels and calcium channel-mediated signaling pathways. It inhibits angiogenesis, tumor growth, invasion, and metastasis. We hypothesized that CAI would promote disease stabilization lasting >/= 6 months in patients with relapsed ovarian cancer. PATIENTS AND METHODS: Patients with epithelial ovarian cancer, good end-organ function, measurable disease, and three or fewer prior regimens were eligible. Oral CAI was given daily using a pharmacokinetic-dosing approach to maintain plasma concentrations between 2 and 4 microg/mL. Radiographic imaging to assess response was performed every 8 weeks. Positive outcome included stabilization or improvement of disease lasting >/= 6 months. Plasma vascular endothelial growth factor (VEGF), interleukin (IL)-8, and matrix metalloproteinase (MMP)-2 were measured. RESULTS: Thirty-six patients were assessable for primary end point analysis, and 38 were assessable for toxicity. Forty-four percent of patients had three prior regimens, more than 50% had four or more disease sites, and 48% had liver metastases. Thirty-three patients reached the targeted concentration range during the first cycle. Eleven patients (31%) attained the >/= 6-month outcome end point, with one partial response (8 months) and three minor responses (8, 12+, and 13 months). Median time to progression was 3.6 months (range, 1.6 to 13.3 months). CAI was well tolerated, with mostly grade 1 to 2 toxicity. Grade 3 events included fatigue (5%), vomiting (2%), neutropenic fever (2%), and neutropenia (2%). There were no grade 4 adverse events. No associations between VEGF, IL-8, and MMP-2 with CAI concentration or clinical outcome were observed. CONCLUSION: CAI is a potential agent for additional study in the stabilization of relapsed ovarian cancer. Given a limited toxicity profile, it may have utility as a maintenance therapeutic agent for this disease.

Administration, Oral↗
PubMed2003

Clear cell tumors have higher mRNA levels of ERCC1 and XPB than other histological types of epithelial ovarian cancer.

PURPOSE: The purpose of the present work was to investigate the relationship between mRNA expression of ERCC1 and XPB, two key genes in the nucleotide excision repair pathway, and clinical resistance of platinum-chemotherapy in histological subtypes of epithelial ovarian cancer. EXPERIMENTAL DESIGN: mRNA levels of ERCC1 and XPB in epithelial ovarian cancer specimens from 126 different individuals were assessed using reverse transcription-PCR and followed by Southern hybridization methodology. Data were analyzed by linear regression analyses and by exhaustive regression analyses. RESULTS: Five different histological types of tumors were examined; serous (n = 76), mucinous (n = 11), clear cell (n = 9), poorly differentiated (n = 9), and endometroid (n = 21). Numerical values for mRNA expression levels were based on internal controls for a stable comparative cell line and for beta-actin. Median values for ERCC1 and XPB mRNAs within clear cell tumors were, on average, >2-fold higher than the other histological tumor types. Linear regression analyses suggest a continuum of nucleotide excision repair gene expression among these cell types, and exhaustive regression analyses demonstrate that the higher mRNA levels seen in clear cell tumors are highly statistically significant. CONCLUSIONS: We conclude that mRNA levels of ERCC1 and XPB tend to be higher in clear cell tumors as opposed to other types of epithelial ovarian cancer. This is consistent with the long-standing observation that clear cell tumors are more likely to show de novo drug resistance against DNA damaging agents in the clinic.

Adenocarcinoma, Clear Cell↗
PubMed2003

A phase I/II study of high-dose tamoxifen in combination with vinblastine in patients with androgen-independent prostate cancer.

In this phase I/II clinical trial the antitumor activity of high-dose tamoxifen when administered in combination with vinblastine was assessed and the toxicity profile of this combination characterized. All 25 patients enrolled in this study were required to have androgen-independent prostate cancer and to maintain androgen ablation during treatment. Vinblastine was given by continuous infusion over 5 days. Doses were increased from 0.9 mg/m2/day to 1.5 mg/m2/day in successive cohorts of at least 3 patients, with no further escalation even in the absence of dose-limiting toxicity. Intra-patient dose escalation was permitted. Tamoxifen was administered at a dose of 200 mg/kg on day 1, then 120 mg/kg/day on day 2. Standard response criteria were utilized to assess antitumor activity and CTC toxicity criteria were used. Quality of life (QOL) pain assessments were evaluated at each visit to the clinic. Most patients tolerated the highest dose of vinblastine at 1.5 mg/m2/day by continuous infusion over 5 days with 200 mg/kg/day of tamoxifen on day 1 and day 2. One patient had a greater than 50% decline in prostate-specific antigen that lasted for 170 days. Two patients received dose reductions because of toxicity. The most common serious toxicities included neutropenia, and fatigue. Reversible neurosensory, neuromotor, neurocortical and neurocerebellar toxicities were reported. Six of the 25 patients enrolled in the study (24%) experienced reversible neurologic toxicity of at least grade III. No statistically significant differences between precycle assessment of QOL and subsequent cycles were observed. It is concluded that vinblastine at 1.5 mg/m2/day continuous i.v. infusion combined with tamoxifen 200 mg/kg/day on day 1 and day 2 is inactive, and not without toxicity in the treatment of advanced metastatic androgen-independent prostate cancer.

Aged↗
PubMed2003

Factors involved in the pharmacokinetics of COL-3, a matrix metalloproteinase inhibitor, in patients with refractory metastatic cancer: clinical and experimental studies.

COL-3 is an oral, lipophilic, tetracycline analog that has been administered to patients with metastatic cancer. Preliminary assessment of COL-3 in 35 patients with refractory metastatic carcinoma demonstrated apparent nonlinear pharmacokinetics with highly variable oral clearance (63.9% coefficient of variance [CV]). To elucidate possible sources of variability of COL-3 pharmacokinetics in vivo, in vitro plasma protein binding and in vitro metabolism were explored along with in vivo pharmacokinetics using compartmental modeling. The variability in the overall clearance and urinary excretion of COL-3 was also assessed. COL-3 had a long terminal half-life (median = 59.8 h), large apparent volume of distribution (median = 50.2 L), and low apparent clearance (median = 9.93 mL/min). Only adjusted ideal body weight decreased the variability in total apparent clearance. There was nonsaturable plasma protein binding of COL-3 (fu = 5.5%), with the majority of binding to albumin. The renal route of elimination is negligible, with 0.06% of unchanged COL-3 and 3.31% COL-3 glucuronide excreted in the first 6 days. COL-3 is not metabolized by phase I metabolism but does undergo glucuronidation in vitro by UGT1A1, UGT1A3, UGT1A9, and UGT2B7 and in vivo, as evidenced by COL-3 glucuronides in the urine (median = 13.6% of the total dose). COL-3 exhibits nonlinear pharmacokinetics, possibly due to dissolution rate-limited absorption.

Administration, Oral↗
PubMed2003

Effects of thalidomide on the expression of angiogenesis growth factors in human A549 lung adenocarcinoma cells.

Angiogenesis is a critical step for the growth and metastasis of solid tumors, and it is a major therapeutic target for the development of anti-angiogenics for cancer treatment. Thalidomide is reported to be an anti-angiogenic agent, which is currently in phase II clinical trials for the treatment of advanced malignancies. However, the mechanism of thalidomide in angiogenesis is not completely understood. This study was undertaken to investigate the effect of thalidomide on the expression of angiogenesis growth factors in human lung cancer cells. In this report, we show that thalidomide downregulated the mRNA and protein expression of basic fibroblast growth factor (bFGF) in the human lung adenocarcinoma cell line A549, and that the effect of thalidomide was time and concentration-dependent. In contrast, the expression of vascular endothelial growth factor (VEGF) by thalidomide in these cells was in two phases. The mRNA and protein expression of VEGF was increased in the lung cancer cells treated with 0.6-6 microg/ml thalidomide, while higher concentrations of thalidomide decreased VEGF levels significantly in these cells. These data suggest that the anti-angiogenic or antitumor activity of thalidomide may be partly mediated through the regulation of the levels of angiogenesis growth factors.

Adenocarcinoma↗
PubMed2003

Effects of Kupffer cell inhibition on liver function and hepatocellular activity in mice.

Kupffer cells are the tissue macrophages in the liver and play an important role in the defense mechanisms of the body. However, their role in liver function and hepatocellular activity remains unclear. This study was therefore undertaken to investigate the effect of gadolinium chloride-induced Kupffer cell dysfunction on liver function and hepatocellular signaling activity in mice and to establish an animal model for studying the role of Kupffer cells in vivo. Kunming mice were intraperitoneally injected with different doses of gadolinium chloride (GdCl3), a selective inhibitor of Kupffer cells, and the mice were sacrificed at different time periods following the drug administration. Hepatotoxicity and Kupffer cell function, as well as the levels of signaling molecules and inflammatory mediators in liver tissue, were measured. We demonstrated that the administration of 10-20 mg/kg GdCl3 caused apoptosis of Kupffer cells and blocked the Kupffer cell effector function, as shown by a decrease in CD68 expression and phagocytic activity. In addition, the NO, PGE2 and cAMP levels in the liver were also reduced significantly. Furthermore, 20 mg/kg GdCl3 decreased the levels of cNOS, PKC and NF-kappaB p65 expression by 26.6, 68 and 64%, respectively. In contrast, hepatotoxicity was not observed when the same doses of GdCl3 were used. Moreover, we found that Kupffer cell function and the NO, PGE2 and cAMP contents, as well as PKC and NF-kappaB p65 levels in the liver were only partially, but not fully recovered in up to six days following 20 mg/kg GdCl3 injection. However, the administration of higher doses of GdCl3 (40 mg/kg) caused both hepatotoxicity and Kupffer cell necrosis, as well as an increased release of TNF, NO, and PGE2 in the liver. These results indicate that administration of suitable doses of GdCl3 blocked the effector function of Kupffer cells selectively, but did not cause liver parenchymal cell toxicity, and provide a frame-work for the establishment of an animal model for studying the role of Kupffer cells in signaling in the liver. Lastly, the present study also provides evidence that shows there is a positive association between the expression of cAMP, PKC, or NF-kappaB and the levels of NO, PGE2 and TNF in the liver of Kupffer-cell-blocked mice, and suggests that Kupffer cells may play a part in mediating liver function and hepatocellular activity.

Adenosine Triphosphatases↗
PubMed2002

Suramin's development: what did we learn?

Suramin, a polysulphonated napthylurea, has been extensively evaluated over the past 10 years as an anticancer agent, with the most interest in the treatment of prostate cancer. Early clinical results were promising with response rates of up to 70% being reported. However, a recent double-blind study showed only modest palliative effect in patients with androgen independent prostate cancer. In retrospect, it appears those initial reports failed to control for confounding variables such as antiandrogen withdrawal and hydrocortisone. Suramin causes numerous reversible toxicities (lethargy, rash, fatigue, anemia, hyperglycemia, hypocalcemia, coagulopathies, neutropenia, renal and hepatic complications). Neurotoxicity has been the most significant complication and appears to be related to the intensity of the dosing regimen. An optimal therapeutic dose has not been determined, but it is clear that adaptive controls add little benefit. Aside from moderate toxicities and the low therapeutic index in patients with prostate cancer, suramin's development has taught us some valuable lessons (i.e., anti-androgen withdrawal was noted during suramin's development, the use of PSA as an indicator of tumor burden was initiated during the evaluation of suramin). These lessons can be applied to all clinical trials in hormone refractory prostate cancer. Suramin has significantly enhanced the evolution of our knowledge in several areas of prostate cancer biology and treatment.

Antineoplastic Agents↗
PubMed2002

Adenoviral delivery of A-FOS, an AP-1 dominant negative, selectively inhibits drug resistance in two human cancer cell lines.

Activator protein-1 (AP-1) transcription factor has been linked to chemotherapeutic resistance. To assess the clinical efficacy of AP-1 inhibition toward reversing drug resistance, we have developed an adenovirus expressing a dominant negative that inhibits AP-1 DNA binding, namedAdA-FOS. We examined the consequence of AdA-FOS infection on two paired human cancer cell lines, each pair consisting of a parental cell and the drug- resistant derivative. The first pair of cells is the parental human ovarian cancer cell line A2780 and the cisplatin-resistant A2780/CP70 cell line. The second pair of cells is the parental epidermal carcinoma cell line KB8 and the multidrug-resistant (mdr) KB85 cell line. Because of an association of up-regulated AP-1 activity with their drug resistance, these cell lines were considered good targets of AdA-FOS therapy. Following infection of the drug-sensitive and drug-resistant cells, we observed a significant decrease in cell viability of KB85 and A2780/CP70 cells at drug doses normally not lethal to the cell. The parental cell lines, A2780 and KB8 cells, were not similarly affected by AdA-FOS. This decrease in viability was specific to AdA-FOS as an adenovirus control (Advector) did not reverse drug resistance. Although the efficiency of AdA- FOS in therapy would need to be further analyzed with other cisplatin-resistant and mdr cell lines, these results suggest that AP-1 is a therapeutic molecular target and that inhibition of AP-1 DNA binding may be of clinical value in treating chemotherapeutic resistance.

Adenoviridae↗
PubMed2002

The role of an androgen receptor polymorphism in the clinical outcome of patients with metastatic prostate cancer.

The androgen receptor plays a major role in the development and function of normal and malignant prostate cells. Due to the relationship of the androgen receptor and prostatic growth, it has been proposed that polymorphisms within the androgen receptor may play a role in an individual's susceptibility to developing prostate cancer. An inverse relationship has been established between a highly polymorphic trinucleotide repeat located in the first exon of the androgen receptor and the transactivaton function of the receptor. Serum samples were collected from 131 patients with histologically confirmed adenocarcinoma of the prostate, DNA was isolated, and the polymorphic CAG repeat was amplified by PCR and sequenced. The CAG repeat lengths were then compared with age at diagnosis, age at time of study, baseline log(10) PSA, Gleason score, time from diagnosis to initiation of hormonal therapy, time to progression after androgen ablation, and overall survival time. No correlation was found between CAG length and time to progression or overall survival time, but a significant correlation was found between Gleason score and CAG length suggesting that shorter CAG lengths may predict a higher histological grade of prostate cancer.

Adenocarcinoma↗
PubMed2002

Epothilones: a novel class of non-taxane microtubule-stabilizing agents.

The epothilones are a novel class of non-taxane microtubule-stabilizing agents obtained from the fermentation of the cellulose degrading myxobacteria, Sorangium cellulosum. Preclinical studies have shown that the epothilones are more potent than the taxanes and active in some taxane-resistant models. Similar to paclitaxel and other taxanes, the epothilones block cells in mitosis, resulting in cell death. The chief components of the fermentation process are epothilones A and B, with epothilones C and D found in smaller amounts. Trace amounts of other epothilones have also been detected. Pre-clinical studies have shown that epothilone B is the most active form, exhibiting significantly higher antitumor activity than paclitaxel and docetaxel. Several phase I and phase II clinical trials are ongoing with epothilone B and BMS 247550, an epothilone B analog. Preliminary reports indicate these agents are active against human cancers in heavily pre-treated patients. The epothilones appear to be well tolerated, with a side effect profile that is similar to that reported with the taxanes. This article will review some basic aspects of epothilone chemistry and biology, and pre-clinical and preliminary clinical experience with epothilone B and its analog, BMS 247550.

Antineoplastic Agents↗
PubMedDate not supplied

Pharmacogenetic associations of CYP2C19 genotype with in vivo metabolisms and pharmacological effects of thalidomide.

Thalidomide requires cytochrome P450 (CYP)-catalyzed biotransformation for its antiangiogenic property, and CYP2C19 is responsible for 5-hydroxylation and 5'-hydroxylation of thalidomide in human. This study explored a hypothesis that patients with poor metabolizing phenotype of CYP2C19 receive little benefit from thalidomide treatment and that the poor metabolizer genotype is associated with lower ability to form the metabolites. A case-control study was conducted with 63 patients with prostate cancer who had been enrolled in a randomized phase II trial of thalidomide monotherapy (200 to 1,200 mg/day). CYP2C19 polymorphism (CYP2C19(*)2, CYP2C19(*)3, CYP2C19(*)4) was compared with clinical events (prostate-specific antigen (PSA) decline) and formations of the hydroxylated metabolites. Two patients were homozygous for the variant CYP2C19(*)2 allele (poor metabolizing phenotype). Both of these were included in the 25 patients whose PSA failed to demonstrate a decline. While 32% and 48% of the patients had quantifiable levels of 5-hydroxythalidomide and cis-5'-hydroxythalidomide, respectively, these metabolite were below quantification in both poor metabolizing patients. None had CYP2C19(*)3 or CYP2C19(*)4 alleles. Although this study had no power to detect the statistical significance of the CYP2C19 genotype, the findings were consistent with our hypothesis. The role of CYP2C19 polymorphism in thalidomide treatments remains to be elucidated.

Alleles↗
PubMedDate not supplied

Thalidomide down-regulates the expression of VEGF and bFGF in cisplatin-resistant human lung carcinoma cells.

Anti-angiogenic therapy represents one of the most promising treatment modalities for human cancer. Thalidomide (alpha-N-phthalimidoglutarimide) is a potent inhibitor of angiogenesis, and it is reported to overcome classical drug resistance in human multiple myeloma cells. However, the effect of this agent on the expression of angiogenic growth factors in cisplatin-resistant tumors is largely unknown. In the current study, we showed that thalidomide suppressed the expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in cisplatin-resistant human A549DDP lung carcinoma cells. The mRNA levels of VEGF and bFGF were markedly decreased in the A549DDP cells treated with the therapeutic concentrations of thalidomide (0.6-6 micrograms/ml), as determined by RT-PCR analysis. Consistent with these results, thalidomide also significantly reduced the protein levels of VEGF and bFGF in these cells in a dose- and time-dependent manner. This study provided evidence to support the potential therapeutic applications of thalidomide in cisplatin-resistant human lung cancer and other tumors.

Adenocarcinoma↗
PubMedDate not supplied

Breast and ovarian cancer genetics and prevention.

Inherited breast and ovarian cancers account for 10% of all breast and ovarian cancers. Relative to sporadic breast and ovarian cancers, these cancers tend to occur at an earlier age and grow more aggressively. Women with BRCA1 and BRCA2 mutations (BRCA1/2 mutation) have a 65% to 85% cumulative lifetime risk of developing invasive breast cancer and a 15% to 65% cumulative lifetime risk of developing invasive ovarian cancer. Identification of patients with the mutation is therefore crucial, because preventive measures such as prophylactic bilateral mastectomy, prophylactic bilateral salpingpo-oophorectomy and chemoprevention with Tamoxifen can prevent breast and ovarian cancer. Likewise, genetic counseling prior to testing is important, considering the major impact of the test results on an individual's life.

Ataxia Telangiectasia↗
PubMedDate not supplied

Correlation of serum VEGF levels with clinical stage, therapy efficacy, tumor metastasis and patient survival in ovarian cancer.

Vascular endothelial growth factor (VEGF) has been shown to play an important role in tumor growth and progression. However, the clinical implications of VEGF expression in ovarian tumors are not fully understood. We therefore investigated the serum level of VEGF in patients with ovarian tumors and explored the potential use of VEGF as a tumor marker for diagnosis, treatment and prognosis of human ovarian cancer. The serum VEGF (sVEGF) levels in 120 patients with ovarian carcinoma, 25 patients with benign ovarian tumor and 90 healthy female blood donors were measured by an enzyme-linked immunosorbent assay in this study. We also determined the levels of sVEGF in patients with epithelial ovarian cancer before and after surgery. Our results showed that: (i) ovarian cancer patients had significantly higher levels of sVEGF compared to those of patients with benign ovarian tumor or those of healthy individuals. As a cut-off at 100 pg/ml, the sensitivity and specificity of sVEGF levels for diagnosing ovarian carcinoma were 77.1% and 87%, respectively. (ii) sVEGF levels were markedly elevated in patients with advanced stage or poorly-differentiated ovarian cancer, as well as in those with more ascites (>500 ml), as compared to patients with early stage and well-differentiated ovarian cancer, or those with less ascites (<500 ml). However, there was no significant difference in sVEGF levels among different pathological subtypes of ovarian carcinoma. (iii) The post-operative sVEGF levels were significantly lower than the pre-operative sVEGF levels. (iv) We measured significantly higher levels of sVEGF in patients with metastasis as compared to patients lacking metastasis. Lastly (v) the average survival-time in patients with higher levels of sVEGF (>100 pg/ml) was 28 months, while the average survival-time in patients with lower levels of sVEGF (<100 pg/ml) was 35 months, indicating that the elevations in sVEGF level are correlated with patient survival and tumor metastasis in ovarian carcinoma. These data suggest that VEGF may be a useful serological biomarker for clinical diagnosis and prognosis of ovarian cancer, for follow-up of ovarian tumor metastasis and for monitoring the efficacy of therapy in patients with ovarian carcinomas.

Adult↗
PubMedDate not supplied

Down-regulation of cyclin E expression by caffeine promotes cancer cell entry into the S-phase of the cell cycle.

Expression of cyclin E is believed to be a critical factor promoting cell entry into the S-phase and cell proliferation. Indeed, normal proliferating cells and most tumor cell lines are characterized by the existence of a minimal cyclin E threshold level in the G1-phase, and only those cells expressing cyclin E over this threshold enter into the S-phase of the cell cycle. However, through studying clinical tumor tissue specimens, we recently observed that some cancer cells can enter into the S-phase with minimal levels of cyclin E expression. In an effort to establish an in vitro cell model system for studying the mechanisms underlying this phenomenon, we treated MOLT-4 lymphocyte leukemia cells with 50 mM caffeine and found that the levels of cyclin E expression were decreased markedly in these cells following 2 to 4-h exposure to caffeine. Quite unexpectedly, we observed that the percentage of the cells progressing through the S-phase increased despite the reduced levels of cyclin E, as analyzed for the cellular DNA contents, expression of nuclear-bound PCNA, immunolabelling with Ki-67 antibody and incorporation of BrdU. In fact, these cells entered into the S-phase with a level of cyclin E well below the threshold level for untreated cells, thus suggesting that lower levels of cyclin E expression are associated with cell proliferation under certain circumstances. We speculate that caffeine may enhance MOLT-4 cell entrance into the S-phase through activation of Cdc25, which in turn activates cyclin-dependent protein kinases (CDKs) including CDK2 and drives the cell cycle progression; while degradation of cyclin E by the ubiquitin/proteasome pathway may account for the decreased levels of cyclin E in these cells. Our findings from both the MOLT-4 cell line and patients' cancer tissues may help decipher the mystery of the deregulation of cell cycle progression and carcinogenesis in some malignant tumors.

Caffeine↗