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D S Alberts

Publications and source records attributed to D S Alberts.

At least 55 records · Page 3Linked to original sources
PubMed1999

Progress report: the Arizona phase III study of the effect of wheat bran fiber on recurrence of adenomatous colon polyps.

A double-blind, placebo-controlled Phase III cancer prevention trial in subjects with previous resection of adenomatous colon polyps is nearing completion. The study's primary objective is to evaluate the effects of daily dietary supplementation with large (13.5 g/day) versus small (2.0 g/day) doses of wheat bran fiber for 3 years. A summary of the study design and a progress report are presented.

Adenomatous Polyposis Coli↗
PubMed1999

Phase II trial of oral etoposide in recurrent or refractory endometrial adenocarcinoma: a southwest oncology group study.

Oral etoposide has activity in a wide variety of tumors and is well tolerated. Therefore, the efficacy of oral etoposide was assessed as a treatment of metastatic endometrial cancer. To be eligible for this group-wide Southwest Oncology Group trial, patients had to have histologically proven metastatic or recurrent endometrial carcinoma; no previous cytotoxic therapy; and adequate renal, hepatic, and hematologic function, and they had to have given informed consent. Therapy consisted of oral etoposide, 50 mg daily on days 1-21 on a 28-day schedule. Therapy was continued in the absence of toxicity or disease progression. Forty-four eligible women, with a median age of 68 years (range 38-84 years) were treated. Radiotherapy had been delivered to 33 and hormomal therapy to 21. The median duration of therapy was 69 days (range 7-510 days). The treatment was well tolerated. Only one patient had grade 4 neutropenia, and a second had grade 4 anemia. Three patients had grade 3 nausea. One complete and five partial responses (14%) were observed. An additional four patients had unconfirmed responses. Tumor regressions were noted in nodes, bone, and visceral organs. While oral etoposide has only a modest level of activity when used in chemonaive patients, the minimal toxicity of this drug makes it a candidate for use in combination chemotherapy.

Adenocarcinoma↗
PubMed1999

Pharmacokinetics of the green tea derivative, EGCG, by the topical route of administration in mouse and human skin.

PURPOSE: (-)-Epigallocatechin gallate (EGCG), the main physiologically active polyphenol of green tea, is associated with antitumor and antimutagenic activities. The goal of this study was to determine the stability and pharmacokinetic parameters of pure EGCG administered topically to human and mouse skin. METHODS: EGCG was investigated by measuring drug levels of a 10% ointment formulation stored under different conditions over a period of 6 months. To determine pharmacokinetic parameters of EGCG following topical application. EGCG was applied as 10% EGCG in hydrophilic ointment USP to full-thickness mouse or human skin in vitro. The transdermal and intradermal. Penetration of EGCG was measured by reverse phase HPLC assays at different time-points. RESULTS: The stability of EGCG in hydrophilic ointment USP was dependent on time, temperature and the degree of oxidation. For example, 10% EGCG was lost after 2 days at 37 degrees C, but the same formulation supplemented with 0.1% butylated hydroxytoluene (BHT) had significantly longer stability with > or =90% EGCG remaining after 130 days at 37 degrees C. Topical application of EGCG in hydrophilic ointment USP to human or mouse skin resulted in substantial intradermal uptake of up to 1-20% of the applied dose. However, transdermal penetration was observed only in mouse skin. CONCLUSION: The present study showed that topical application of EGCG in hydrophilic ointment USP achieved high concentrations in skin but negligible systemic availability. The drug was susceptible to oxidation, but if supplemented with BHT, the hydrophilic ointment formulation could potentially be used in clinical trials of skin cancer prevention.

Administration, Topical↗
PubMed1999

Topical DMSO treatment for pegylated liposomal doxorubicin-induced palmar-plantar erythrodysesthesia.

PURPOSE: Chemotherapeutic regimens that utilize fluorouracil, cytarabine, and doxorubicin have been shown to cause a dermatologic syndrome known as hand-foot syndrome, or palmar-plantar erythrodysesthesia syndrome (PPES). Pegylated liposomal doxorubicin has proven effective in the treatment of AIDS-related Kaposi's sarcoma, ovarian cancer refractory to platinum and paclitaxel therapies, and metastatic breast cancer. In a study of the treatment of refractory epithelial cell ovarian cancers with lipozomal doxorubicin utilizing intravenous doses of 50 mg/m(2) every 3 weeks, grade 3 PPES was observed in 29% of patients (10/35) and required dose reductions and/or dose delay after a median of three therapy cycles. METHODS: Current methods to prevent pegylated liposomal doxorubicin-induced PPES include dose reduction, lengthening of the drug administration interval and ultimately, drug withdrawal. Topical 99% dimethylsulfoxide (DMSO) also has shown strong activity in treating tissue extravasation reactions during intravenous administration of doxorubicin. RESULTS: Two patients undergoing chemotherapy with pegylated liposomal doxorubicin, 50 mg/m(2) every 4 weeks, developed grade 3 PPE after three cycles. Their PPES resolved over a period of 1 to 3 weeks while receiving topical 99% DMSO four times daily for 14 days. CONCLUSIONS: While these results are promising, patients must be treated in a prospective study of this topical DMSO formulation to definitively document its therapeutic efficacy.

Administration, Topical↗
PubMed1999

A convenient synthesis of dinorbile acids: oxidative hydrolysis of norbile acid nitriles.

We report a convenient method for the synthesis of dinorbile acids (23,24-dinor-5beta-cholan-22-oic acids, pregnane-20-carboxylic acids) in fair to good yields from norbile acid nitriles in one step by oxidative hydrolysis with oxygen in the presence of potassium-t-butoxide. The method results in stepwise overall removal of two carbon atoms in bile acid side chains in two steps. Dinorbile acids corresponding to several common bile acids have been prepared and their structures confirmed by spectroscopic methods. This simple method for synthesis of dinorbile acids may facilitate their study metabolically.

Bile Acids and Salts↗
PubMed1999

Relationship of p53 mutations to epidermal cell proliferation and apoptosis in human UV-induced skin carcinogenesis.

Human skin is continually subjected to UV-irradiation with the p53 gene playing a pivotal role in repair of UV-induced DNA damage and apoptosis. Consequently, p53 alterations are early events in human UV-induced skin carcinogenesis. We studied 13 squamous cell carcinomas (SCC), 16 actinic keratoses (AK), 13 samples adjacent to an AK (chronically sun-damaged), and 14 normal-appearing skin samples for p53 mutation, p53 immunostaining (IHC), apoptosis (in situ TUNEL and morphology), and proliferation (PCNA). The frequency of p53 mutation increased from 14% in normal skin, to 38.5% in sun-damaged skin, 63% in AK, and 54% in SCC. p53 IHC increased similarly. Apoptosis (TUNEL) increased from 0.06 +/- 0.02%, to 0.1 +/- 0.2, 0.3 +/- 0.3, and 0.4 +/- 0.3 in normal skin, sun-damaged skin, AK, and SCC, respectively. Apoptosis was strongly correlated with proliferation (i.e., TUNEL and PCNA, r = 0.7, P < 0.0001), and proliferation was significantly increased in the progression from normal skin to SCC. Bax was significantly increased in SCC compared to AK. These data imply that apoptosis in samples with a high frequency of p53 mutation may not necessarily be p53-dependent. We suggest that there is a mechanism for apoptosis in response to increased cellular proliferation that is p53-independent.

Aged↗
PubMed1999

Treatment of refractory and recurrent ovarian cancer.

Patients with recurrent ovarian cancer can be divided into two groups: those who have recurrence more than 6 months after primary therapy with paclitaxel/platinum (ie, platinum-sensitive) and those with tumor progression or recurrence within 6 months of primary therapy (ie, platinum-resistant). In patients with platinum-sensitive tumors and good performance status, re-treatment with paclitaxel/platinum combination therapy is usually the most appropriate choice. For patients with minimum residual disease, the greatest promise for long-term disease-free survival is associated with intensive intraperitoneal therapy with combinations of cisplatin and intravenous/intraperitoneal paclitaxel. Alternatively, patients with platinum-sensitive disease can receive intravenous carboplatin or paclitaxel. Patients with platinum-resistant ovarian cancer can benefit from single-agent therapy with altretamine, topotecan, oral etoposide, ifosfamide, liposomal doxorubicin, or other standard or investigational regimens. (Of these drugs, only altretamine and topotecan are approved by the US Food and Drug Administration for persistent or recurrent ovarian cancer.) Since the response rates achieved with these drugs are similar, patient convenience, side effects, and cost may play a significant role in drug selection.

Algorithms↗
PubMed1999

Protection by amifostine of cyclophosphamide-induced myelosuppression.

The dose and schedule of administration of chemotherapeutic agents are often dictated by their bone marrow toxicity. Cumulative bone marrow damage may be associated with chronic exposure to chemotherapeutic agents such as alkylating agents. Amifostine (Ethyol; Alza Pharmaceuticals, Palo Alto, CA/US Bioscience, West Conshohocken, PA), a cytoprotective agent, protects bone marrow from this type of cumulative toxicity. Three well-controlled clinical trials have shown that amifostine can ameliorate cumulative bone marrow toxicity and the acute and chronic neutropenic and/or thrombocytopenic effects of cyclophosphamide. In a pivotal phase III study of cisplatin/cyclophosphamide with or without amifostine, amifostine treatment reduced course-by-course cumulative bone marrow damage when compared with the course-by-course cumulative myelosuppression experienced by those treated with cisplatin/cyclophosphamide alone. Despite this clinically significant cytoprotection, amifostine treatment did not adversely affect pathologically proven complete response, overall objective response rates, or survival duration associated with cisplatin/cyclophosphamide chemotherapy.

Amifostine↗
PubMed1999

Future directions in gynecologic cancer.

Cisplatin is one of the most commonly used chemotherapeutic agents to treat gynecologic cancers. However, many patients treated with platinum therapy experience significant toxicities, including neurotoxicity, ototoxicity, and/or nephrotoxicity. Clinical trials have documented the role of amifostine as a cytoprotectant against cisplatin-induced toxicities in patients with advanced ovarian cancer. In these trials, the incidence and severity of many dose-limiting toxicities was reduced significantly by the concomitant administration of amifostine. The management of advanced ovarian, cervical, and endometrial cancers provides many opportunities for future applications of amifostine. Several studies that are being initiated in the United States involve maintaining platinum dose intensity, reducing toxicities, and developing chemotherapeutic combinations that would otherwise have to be avoided without the use of a cytoprotective agent such as amifostine.

Amifostine↗
PubMed1999

Chromosome abnormalities in ovarian adenocarcinoma: I. Nonrandom chromosome abnormalities from 244 cases.

Cytogenetics provides important insights into the molecular pathogenesis of human cancers. Although extensive data exist on recurring cytogenetic abnormalities in hematologic cancers, data on individual solid tumor types remain limited. Previous studies of ovarian carcinoma indicated the presence of multiple, complex clonal chromosome abnormalities. Cytogenetics remains one of a few techniques capable of detecting these multiple, simultaneously occurring genetic abnormalities. We describe cytogenetic abnormalities from a series of 244 primary ovarian cancer specimens referred to a single institution. A total of 201/244 cases had fully characterized clonal chromosome abnormalities, of which 134 showed clonal chromosome breakpoints. We used a novel statistical technique to detect nonrandom chromosome breakpoints at the level of chromosome regions. Nonrandom occurrence of chromosome breakpoints was detected at regions 1p1*, 1q1*, 1p2*, 1q2*, 1p3*, 1q3, 3p1*, 1q4*, 6q1*, 6p2, 6q2, 7p1*, 7q1, 7p2*, 11p1*, 11q1, 11q2*, 12p1, 12q2*, 13p1, and 19q1. Simultaneous occurrence of multiple abnormalities was common. However, 120/134 cases had breakpoints at one or more of 13 commonly involved regions (*), suggesting a hierarchy of genetic abnormalities. Among clinical and tumor variables that predict patient survival, tumor grade was significantly associated with the presence of chromosome breakpoints. In additional studies, we show that nonrandom chromosome abnormalities are associated with impaired survival in ovarian cancer and that specific, nonrandomly involved chromosome regions retain significant effects on survival when analyses are controlled for important clinical variables. Additional specific chromosome abnormalities in this series are described, including chromosome gains and losses in near-diploid cases and homogeneously staining regions. These results suggest that recurring, nonrandom chromosome abnormalities are important in the pathogenesis and/or progression of ovarian cancers, and target areas of the genome for molecular genetic studies.

Adenocarcinoma↗
PubMed1999

Expression in normal human tissues of five nucleotide excision repair genes measured simultaneously by multiplex reverse transcription-polymerase chain reaction.

DNA repair is central to the integrity of the human genome. Reduced DNA repair capacity has been linked to genetic susceptibility to cancer. An adequate expression level of DNA repair genes is essential for normal DNA repair activities. Although there is tissue specificity in the expression, searching for a surrogate tissue is needed for molecular epidemiological studies. In this study, the relative expression levels of five selected human nucleotide excision repair (NER) genes (ERCC1, XPB/ERCC3, XPG/ERCC5, CSB/ERCC6, and XPC) in 20 different types of human normal tissue were simultaneously measured by a new multiplex reverse transcription (RT)-PCR assay using the expression level of the beta-actin gene as an internal control. Transcripts of each of the five NER genes were detectable, but the levels varied in these normal tissues. Both mitogen (phytohemagglutinin)-stimulated and unstimulated human peripheral lymphocytes showed similar expression patterns for the five NER genes. In general, the expression levels of stimulated lymphocytes were also similar to most of the rapidly proliferating tissues, such as the skin, breast, intestine, liver, testis, ovary, placenta, or prostate, but was relatively higher than that of the slowly proliferating or nonproliferating tissues such as adipose, brain, hippocampus, muscle, spleen, or lung. The data suggested that although the five NER genes were expressed at different levels in the normal tissues examined, PHA-stimulated peripheral lymphocytes may be used as a surrogate tissue for estimating expression levels of these genes in proliferating tissues. This new multiplex RT-PCR assay may help detect aberrant expression of these NER genes in both normal and tumor tissues.

Cell Line↗
PubMed1999

Reliability and validity of a self-administered food frequency questionnaire in a chemoprevention trial of adenoma recurrence.

Various chemoprevention trials have assessed dietary intake by means of food frequency questionnaires. However, it is important to assess the degree to which such questionnaires can measure diet. We conducted reproducibility and validity analyses of our Arizona Food Frequency Questionnaire (AFFQ) in our recently completed, randomized, Phase III chemoprevention trial testing the effects of a wheat bran fiber supplement on colorectal adenoma recurrence. A total of 139 individuals provided a baseline and year 1 AFFQ and a set of 4-day dietary records collected over a period of 1 month. The reproducibility analyses of the AFFQ administered 1 year apart showed a mean intraclass correlation of 0.54 for unadjusted nutrients and 0.48 for energy-adjusted nutrients. The relative validity of the AFFQ, as compared with the average of the 4-day diet records, showed a mean deattenuated correlation of 0.49 (range, 0.22-0.65) for the baseline AFFQ and 0.49 (range, 0.25-0.67) for the year 1 AFFQ. When data from both AFFQs were combined and compared with the diet records, there was a slight improvement in the overall deattenuated correlations (mean, 0.56; range, 0.33-0.71). The correlations we observed for macro- and micronutrient intake were within the overall range of those reported in the literature. Reliability and validity studies of dietary instruments are feasible in the setting of a chemoprevention trial and should be conducted when the instrument's performance has not been previously assessed in the target population.

Adenomatous Polyps↗
PubMed1998

In vitro phase II comparison of the cytotoxicity of a novel platinum analog, nedaplatin (254-S), with that of cisplatin and carboplatin against fresh, human cervical cancers.

OBJECTIVE: To compare the in vitro cytotoxicity of nedaplatin, an investigational platinum analog, with that of cisplatin and carboplatin against fresh cervical cancers from untreated patients. METHODS: Specimens were obtained prior to irradiation or radical surgery from 20 patients with locally invasive cervical carcinoma. Cytotoxicity was measured after single cell suspensions were grown in agar using colony counts and incorporation of [3H]thymidine. Nedaplatin and cisplatin were tested at 1 and 10 micrograms/ml dose levels while carboplatin was tested at 10 and 100 micrograms/ml dose levels continuously. When single hour exposures were used, drug doses were increased by 10-fold. RESULTS: The median drug concentrations associated with a 50% inhibition of growth (IC50) for nedaplatin, cisplatin, and carboplatin were 0.435, 0.73, and 18.6 micrograms/ml, respectively. At 10 micrograms/ml for both cisplatin and nedaplatin and 100 micrograms/ml for carboplatin, cisplatin was the most active drug with 70% of tumors sensitive (</=50% survival relative to control plates) to cisplatin and 45 and 50% sensitive to nedaplatin and carboplatin, respectively (P = 0.015, P = 0.074). Six of 20 (30%) tumors resistant to cisplatin were also resistant to nedaplatin and carboplatin. CONCLUSION: At doses approximating clinically achievable drug concentrations as defined by the mean plasma concentration time product, cisplatin appears more cytotoxic in vitro than either carboplatin or nedaplatin among chemotherapy-naive cervical cancers. However, nedaplatin and carboplatin are also active agents with similar activity. Since differences in drug sensitivity may be related to subtle differences in dose and schedule and the pharmacokinetics and safety profile of nedaplatin are favorable, clinical trials of nedaplatin are indicated.

Antineoplastic Agents↗
PubMed1998

13-cis-retinoic acid or all-trans-retinoic acid plus interferon-alpha in recurrent cervical cancer: a Southwest Oncology Group phase II randomized trial.

PURPOSE: Preclinical and clinical data support the study of retinoids and interferon-alpha (IFN-alpha) in advanced squamous cell carcinoma of the uterine cervix (SCC). This phase II randomized trial of the Southwest Oncology Group sought to estimate the response rate for IFN-alpha plus either 13-cis-retinoic acid (13cRA) or all-trans-retinoic acid (ATRA) in women with recurrent cervical SCC. PATIENTS AND METHODS: Eligibility for this trial required bidimensionally measurable locally recurrent or metastatic squamous or adenosquamous carcinoma of the uterine cervix; SWOG performance status of </=2; no prior interferon, retinoids, or chemotherapy (except as radiation sensitization). All but two patients were previously treated with surgery, radiation therapy, or both. After randomization, patients received IFN-alpha-2A (subcutaneous injection; 3 x 10(6) units/m2/day) plus either 13cRA (1 mg/kg/day orally) or ATRA (150 mg/m2/day orally) in two equally divided doses. RESULTS: Total enrollment was 63 patients, 21 in the ATRA arm, 42 in the 13cRA arm. Three patients were ineligible, 1 in the ATRA arm, 2 in the 13cRA arm. Each arm had 1 patient who received no assigned treatment and was not evaluated for response or toxicity. The ATRA/IFN-alpha response rate was 5% (1/19; 95% confidence interval = 0.1-26%), consisting of 1 partial response lasting 4 weeks. The 13cRA/IFN-alpha response rate was 8% (3/39; 95% confidence interval = 2-21%), consisting of 3 partial responses lasting 17, 22, and 24 weeks, respectively. All confirmed responses were partial. One additional unconfirmed partial response occurred in the 13cRA arm. Both regimens were generally well-tolerated and produced toxicities (principally malaise and fatigue) associated with each constituent agent's known single-agent side effects. CONCLUSION: Based upon the results of this study, neither regimen can be recommended for further study in patients previously treated with radiation therapy.

Adult↗
PubMed1998

Chemotherapy in advanced ovarian cancer: four systematic meta-analyses of individual patient data from 37 randomized trials. Advanced Ovarian Cancer Trialists' Group.

The purpose of this systematic study was to provide an up to date and reliable quantitative summary of the relative benefits of various types of chemotherapy (non-platinum vs platinum, single-agent vs combination and carboplatin vs cisplatin) in the treatment of advanced ovarian cancer. Also, to investigate whether well-defined patient subgroups benefit more or less from cisplatin- or carboplatin-based therapy. Meta-analyses were based on updated individual patient data from all available randomized controlled trials (published and unpublished), including 37 trials, 5667 patients and 4664 deaths. The results suggest that platinum-based chemotherapy is better than non-platinum therapy, show a trend in favour of platinum combinations over single-agent platinum, and suggest that cisplatin and carboplatin are equally effective. There is no good evidence that cisplatin is more or less effective than carboplatin in any particular subgroup of patients.

Antineoplastic Agents↗
PubMed1998

Nuclear morphometry in solar keratosis.

OBJECTIVE: To carry out a feasibility study for the development of procedures for the objective characterization and grading of solar keratotic skin lesions. STUDY DESIGN: Imagery from sections of skin shave biopsies from 12 light-skinned individuals were digitized. A minimum of 25 nuclei from a solar keratotic lesion and 25 nuclei from a location in histologically normal appearing skin adjacent to the lesion were recorded for each case. Values of karyometric features were computed, and a discriminant function distinguishing normal nuclei from nuclei exhibiting solar irradiation damage was derived. RESULTS: Approximately 50% of nuclei in solar keratotic lesions were markedly affected by solar irradiation, but even in biopsies from histologically normal appearing skin, 3-30% of nuclei showed signs of such damage. Nuclei from solar keratotic lesions exhibiting such damage had numerous morphometric and karyometric features commonly found in malignant cells. The state of progression of a solar keratotic lesion can be graded by a plot of proportion of nuclei exhibiting solar damage versus the average discriminant function score of the most affected nuclei. This plot provides a monotonically rising progression curve and a numeric grading score. CONCLUSION: Karyometry of nuclei from skin biopsies allows objective assessment of the progression of solar keratotic lesions. Similarity of feature values in nuclei from solar keratotic lesions to those in malignant lesions was noted. The progression curve derived in this study could serve to measure the efficacy of chemopreventive or therapeutic intervention.

Biopsy↗
PubMed1998

Design and baseline characteristics of study participants in the Wheat Bran Fiber trial.

The Wheat Bran Fiber (WBF) trial is a Phase III clinical trial designed to assess the effect of a WBF intervention for 3 years on the recurrence of adenomatous polyps. Men and women, 40-80 years of age, who had removal of one or more colorectal adenoma(s) 3 mm or larger within 3 months prior to study entry were recruited from three sites in the Phoenix metropolitan area. After meeting eligibility criteria, 1509 individuals entered a 6-week run-in period, consisting of a low WBF (2 g/day) intervention. Participants (n = 1429) successfully completed this phase and were randomized to a high (13.5 g/day) or low (2 g/day) WBF intervention. Various data and specimens were collected at baseline and throughout the intervention phase, which included dietary intake, physical activity, other risk factor information, blood specimens, rectal biopsies, and polyp tissues. The study design called for a colonoscopy at approximately 1 year after the qualifying colonoscopy; thus, the period between the first year and the final colonoscopy will be used to assess the effect of the intervention, which is expected to be completed in the latter part of 1998.

Adenomatous Polyps↗