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E Reed

Publications and source records attributed to E Reed.

At least 19 recordsLinked to original sources

ERCC1 and ERCC2 expression in malignant tissues from ovarian cancer patients.

BACKGROUND: ERCC1 and ERCC2 are human DNA repair genes that are associated with in vitro resistance to selected DNA-damaging agents. PURPOSE: Fresh tumor tissues from 26 patients with ovarian cancer were analyzed for the RNA levels of expression of these genes to determine possible clinical relevance. METHODS: Tumor tissues were harvested from patients immediately before they entered a cisplatin- or carboplatin-based treatment protocol. Clinical response was assessed by standard criteria. Gene expression level was assessed by slot blot analysis, using beta-actin as a control. Relative expression levels were determined by comparing each tumor sample with a Chinese hamster ovary cell line that had a stable transfection of the human ERCC1 gene. RESULTS: Patients who were clinically resistant to platinum-based therapy had a 2.6-fold higher expression level of ERCC1 in their tumor tissue than did patients who responded to that therapy (P = .015). Results obtained by slot blot analysis were qualitatively confirmed by polymerase chain reaction analysis. Relative levels of expression of ERCC2 did not differ significantly between responders and nonresponders. CONCLUSION: We conclude that ERCC1 expression levels in human tumor tissue may have a role in clinical resistance to platinum compounds. These data appear to be consistent with the assertion that ERCC1 serves as an excision nuclease, whereas ERCC2 serves as a helicase.

Blotting, Southern

Multiple biological markers in germ cell tumor patients treated with platinum-based chemotherapy.

Blood samples from 36 germ cell tumor patients receiving chemotherapy with either cisplatin or carboplatin in combination with other drugs [etoposide or vinblastine, cyclophosphamide, dactinomycin, and bleomycin (VAB-6)] were analyzed for the presence of 7 different biological markers. The biomarkers included platinum-protein adducts, platinum-DNA adducts, sister chromatid exchange (SCE), micronuclei (MN), and somatic gene mutation at the hypoxanthine phosphoribosyl transferase (HPRT) locus and the glycophorin A (GPA) loci (NO and NN). Patients were asked to donate 9 serial blood samples: a pretreatment sample followed by another drawn 12-24 h after each of four cycles of treatment and a final sample provided 3-6 months after the last cycle. Most individuals gave 7-8 samples; 7 individuals donated all 9. Because of limited amounts of cells in some cases, it was not possible to carry out all 7 assays on every sample. Pt-protein adducts, Pt-DNA adducts, and SCE showed a direct and consistent effect of treatment and were very highly correlated. A significant correlation was also seen between both Pt-protein and Pt-DNA adducts and HPRT mutation. All of the posttreatment samples were significantly elevated compared to the baseline sample. These markers also remained elevated 3-6 months after the end of treatment. By contrast, MN, HPRT mutation, and GPA mutation (both NO and NN variants) showed varying patterns of dose response, probably reflective of the differing biology of these markers scored in lymphocytes (MN and HPRT) and erythrocytes (GPA). MN were significantly elevated in the posttreatment samples drawn at cycles 2 and 3. Although induction of HPRT mutation was only of marginal significance, results here are for the mutant frequency determination assay only. In progress is the potentially more informative analysis of the type of mutations by Southern blot and the sequencing of mutations to look for characteristic mutational spectra. The GPA assay showed a significant increase over baseline in samples drawn after cycles 3 and 4 (NO variants) and after cycles 2, 3, and 4 (NN variants). The level of GPA mutation (both NO and NN variants) was clearly elevated even 3-6 months after the last cycle of chemotherapy. Correlations were seen between HPRT and MN as well as between GPA NO and GPA NN variants. Analysis of biomarkers by treatment group does not reveal a consistent pattern or trend across all cycles.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent

Host cell reactivation of cisplatin-damaged plasmid DNA in human non-T leukocyte cell lines.

Host-cell reactivation of cisplatin-damaged pRSVcat was assessed in three B cell lines (SKW 6.4, WIL2-NS, RPMI 1788), the monocytic cell line THP-1, and promyelocytic HL-60 cells. IC50 values following a 3-day exposure of the five leukocyte cell lines to cisplatin ranged from 0.45 to 1.92 microM. Transfer of pRSVcat into all cell lines was effected by electroporation and the resultant CAT activity was measured 24 h later by a rapid single vial CAT assay. CAT activity corresponding to an average of 0.06 units of purified CAT enzyme was expressed by WIL2-NS cells. Very low to no expression of the CAT vector was observed in all other cell lines studied, despite the presence of intracellular levels of 3H-labelled pRSVcat comparable to WIL2-NS. Epstein-Barr virus transformed B cells (SKW 6.4 and RPMI 1788) did not successfully perform host cell reactivation. In WIL2-NS cells, platination of pRSVcat to defined levels of 5-40 platinum molecules per plasmid led to a graded reduction in CAT activity expressed following transfection. Platination levels of 20 and 40 platinum molecules per plasmid did not alter the efficiency of transfer of pRSVcat into these cells by electroporation. Data obtained in this study suggests that EBV transformation may possibly be a negative influence on host cell-reactivation assays for cisplatin-DNA damaged plasmid in non-T human leukocytes.

B-Lymphocytes

Persistence of platinum-ammine-DNA adducts in gonads and kidneys of rats and multiple tissues from cancer patients.

The persistence of platinum-DNA adducts was investigated using normal rats as well as tissues from cancer patients receiving either cisdiamminedichloroplatinum(II) (cisplatin) or diamminecyclobutanedicarboxylatoplatinum(II) (carboplatin) for cancer chemotherapy. These studies used an enzyme-linked immunosorbent assay, established with a rabbit anti-cisplatin-DNA that is specific for intrastrand platinum-DNA adducts. The gonads and kidneys of male and female rats, sites for antitumor activity and toxicity, respectively, were monitored for cisplatin-DNA adduct formation after a single dose of drug and during multiple-dose exposures (once a wk for 3 wk). DNA adducts were measured by enzyme-linked immunosorbent assay 4 h and 2, 4, 7, and 14 days after administering a single i.v. injection of 8 mg/kg of cisplatin. Adduct profiles in renal tissues were similar in both males and females with adduct levels increasing between 4 h and 2 days, decreasing between Days 2 and 7, and stable between Days 7 and 14. In both sexes, levels of kidney DNA adduct measured 7 to 14 days after cisplatin injection comprised about 30% of the highest (Day 2) value. In testes and ovaries, adduct removal was complete by 4 days, and 40 to 50% of adducts present at Day 2 persisted until Days 7 and 14. A study of multiple dosing showed that adducts in renal and testicular DNA from rats given three weekly doses of 5 mg/kg of cisplatin had different accumulation profiles. In the testis there was a 2-fold accumulation of adduct after the third dose, while in the kidney adducts dropped with repeated dosing. In humans, the persistence of platinum-DNA adducts was studied in tissues from eight cancer patients who received their last dose of cisplatin or carboplatin chemotherapy between 1 day and 15 mo before autopsy. The patients had either ovarian cancer, breast cancer, or lymphoma, and the tissues studied included ovarian tumor, bone marrow, kidney, liver, spleen, lymph node, peripheral nerve, and brain. When samples were available from tumor tissues and from bone marrow within the same patient, adduct levels were similar in the two tissues. In addition, adducts were persistent for many months, since half of the individuals received their most recent platinum-drug therapy 7 to 15 mo before death. Overall, these studies demonstrate a widespread distribution and high degree of platinum-DNA adduct persistence in both animal and human tissues subsequent to cisplatin or carboplatin treatment.

Adult

5-Fluorouracil (5-FU) and leucovorin in platinum-refractory advanced stage ovarian carcinoma.

Twenty-nine patients with recurrent advanced stage ovarian cancer were treated with 5-fluorouracil (5-FU) and leucovorin by intravenous bolus on 5 consecutive days, repeated every 3 weeks. Twenty-one of these patients had experienced disease progression while receiving a cisplatin- or carboplatin-based regimen. There were 2 clinical complete responders and 1 partial responder to therapy (10% response rate; 95% confidence interval, 2 to 27%) and 11 individuals who experienced stable disease for periods ranging from 5 to 27 months. Of 204 cycles of therapy administered, 9 cycles were associated with hospitalization. These occurred in the more heavily pretreated members of the cohort. 5-FU and leucovorin appear to have activity in platinum-refractory ovarian cancer and form a well-tolerated regimen in most patients.

Adult

Determinants of cisplatin sensitivity in non-malignant non-drug-selected human T cell lines.

We have studied molecular mechanisms of cisplatin sensitivity and resistance in 3 non-malignant, non-drug-selected human T lymphocyte cell lines. HuT 78, H9, and MOLT-4 cells were assessed for sensitivity to cisplatin, DNA damage levels following defined drug exposures, drug accumulation, and DNA repair efficiency as measured by adduct removal from cellular DNA and by host-cell reactivation of cisplatin-modified plasmid DNA. Based on 3-day continuous drug exposures, the IC50 values for the cell lines were: HuT 78, 0.83 microM; H9, 0.45 microM; and MOLT-4, 0.33 microM. These cells retained this order with respect to DNA repair capability, whether measured by platinum-DNA adduct removal from cellular DNA or by host-cell reactivation assays. DNA repair values measured by these two assays were directly related to one another with a linear correlation coefficient of 0.993. At sublethal cisplatin doses the more resistant cells showed the highest levels of drug uptake. When drug uptake levels were 'corrected' for drug-induced cell kill, there were equal levels of DNA repair efficiency for a given level of drug uptake. Absolute levels of cisplatin-DNA adduct repair increased with increasing drug dose. However, at supralethal doses of drug, efficient DNA repair could be overcome in all 3 cell lines with percentage-adduct-removal dropping from a 60-80% range to a less than 30% range. We conclude that in non-malignant non-drug-selected human T cells, DNA repair appears to be the primary determinant of cisplatin sensitivity/resistance and that enhanced DNA repair may be a biologic compensatory mechanism for cells that cannot prevent cellular uptake of DNA-damaging agents.

Cell Line

Suramin in advanced platinum-resistant ovarian cancer.

10 patients with ovarian cancer, whose disease had progressed while receiving platinum-based therapy, were entered onto a phase II clinical trial of the antiproliferative agent suramin. Suramin was administered in a fashion that is associated with durable objective disease response in patients with hormonally resistant metastatic prostate cancer. No individual had an objective response to therapy in this study, but 3 of 9 evaluable patients (33%) experienced disease stabilisation and subjective clinical improvement for periods ranging from 2 to 5 months. Disease stabilisation was associated with prolonged periods of comparatively high plasma levels of drug, which appeared to be determined primarily by reduced drug clearance. We conclude that suramin has potential activity in platinum-resistant ovarian cancer, and we have initiated a second clinical trial using pharmacological information derived from this study.

Adult

Therapy of patients with metastatic breast cancer with 5-fluorouracil, leucovorin and carboplatin.

Thirty-four women with metastatic breast cancer were treated at the National Cancer Institute of the National Institutes of Health, with a regimen of leucovorin (L), 500 mg/m2 i.v. over 30 min, followed in 1 h by 5-fluorouracil (5-FU), 375 mg/m2 i.v. bolus on days 1-5, and carboplatin (CBDCA), 50-100 mg/m2 i.v. bolus on days 2-4, every 28 days. All patients had received previous combination chemotherapy with at least one regimen (29 patients with 5-FU-containing regimens). CBDCA, 100 mg/m2 on days 2-4, resulted in grade 4 neutropenia in 10 out of 11 patients associated with sepsis in all 10 patients. CBDCA, 75 mg/m2 (seven patients) and 50 mg/m2 (15 patients), resulted in grade 4 neutropenia in six and eight patients, and neutropenic sepsis in five and two cases, respectively. Grade 4 thrombocytopenia occurred in 10, five and two patients receiving 100, 75 and 50 mg/m2 of CBDCA, respectively. Other toxicities included grade 3/4 mucositis in 18 patients and grade 3/4 diarrhea in 10 patients. Twenty nine patients were evaluable for response, with one pathologic complete response (3%), two partial responses (6%), 18 stable disease (53%) and eight (24%) progressive disease. Sites of response included bone, viscera and soft tissue. The median time from entry on study to progression, for responders, was 15 months. When platinum-DNA adduct formation in peripheral white blood cells was analyzed in 27 patients at 24 h after drug administration, a significant correlation between adduct level and CBDCA cumulative dose was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Population and family studies of HLA-DR4 by use of oligonucleotide typing.

Using PCR and DR4 group-specific primers and SSO's we have examined DRB1*04 nucleotide polymorphisms in a population of 123 DR4-positive individuals (86 NAC, 27 Hispanics and 10 African Americans) from New York carrying a total of 134 DR4 haplotypes. We found that the distribution of DRB1*04 alleles on DR4 haplotypes differs in these three ethnic groups. In this relatively small population, certain alleles such as DRB1*0406 and 0411 were encountered only in Hispanics, while others such as DRB1*0403, 0408 and 0409 were found only in NAC (North American Caucasians). Such differences may be important in studies of HLA-DR4 and disease associations. Evidence from MLC and PLT studies of an HLA-B/DR crossover family, which was informative for the segregation of HLA-DRB1*0406 and DRB1*0407, supports the concept that subtypes of HLA-DR4 and/or associated HLA-DP alleles elicit T-cell alloreactivity, and may thus play a role in transplantation.

Amino Acid Sequence

Polymorphism of HLA in the Romanian population.

We have investigated the HLA-class I and class II polymorphism in a population of 83 Romanians using conventional serology together with PCR amplification and oligonucleotide typing of HLA-class II genes. Romanians show a higher frequency of HLA-A11, B13, B18, B37, B39, B51 and DR2 than other European populations. HLA-DRB1*1501 and 1601 account for the high frequency of the serologic specificity DR2. In Romanians, HLA-DR2 is in linkage disequilibrium with HLA-B18 and HLA-Bw52 rather than with HLA-B7 as in the case in other Europeans. Unexpected HLA-DR2 haplotypes include HLA-DRB1*1502, DQA1*0102, DQB1*0601; HLA-DRB1*1602, DQA1*0102, DQB1*0502. Other unusual haplotypes include HLA-DRB1*0405, DQA1*03, DQB1*0302; HLA-DRB1*1305, DQA1*0103, DQB1*0603; and HLA-DRB1*1405, DQA1*0101, DQB1*05032. Analysis of the genetic distance between Romanians and other Europeans who have been studied serologically are consistent with the hypothesis that Romanians descend from Roman ancestors who colonized Dacia between the 1st century B.C. and 1st century A.D.

Base Sequence

Increased gene-specific repair of cisplatin interstrand cross-links in cisplatin-resistant human ovarian cancer cell lines.

We have studied several aspects of DNA damage formation and repair in human ovarian cancer cell lines which have become resistant to cisplatin through continued exposure to the anticancer drug. The resistant cell lines A2780/cp70 and 2008/c13*5.25 were compared with their respective parental cell lines, A2780 and 2008. Cells in culture were treated with cisplatin, and the two main DNA lesions formed, intrastrand adducts and interstrand cross-links, were quantitated before and after repair incubation. This quantitation was done for total genomic lesions and at the level of individual genes. In the overall genome, the initial frequency of both cisplatin lesions assayed was higher in the parental than in the derivative resistant cell lines. Nonetheless, the total genomic repair of each of these lesions was not increased in the resistant cells. These differences in initial lesion frequency between parental and resistant cell lines were not observed at the gene level. Resistant and parental cells had similar initial frequencies of intrastrand adducts and interstrand cross-links in the dihydrofolate reductase (DHFR) gene and in several other genes after cisplatin treatment of the cells. There was no increase in the repair efficiency of intrastrand adducts in the DHFR gene in resistant cell lines compared with the parental partners. However, a marked and consistent repair difference between parental and resistant cells was observed for the gene-specific repair of cisplatin interstrand cross-links. DNA interstrand cross-links were removed from three genes, the DHFR, multidrug resistance (MDR1), and delta-globin genes, much more efficiently in the resistant cell lines than in the parental cell lines. Our findings suggest that acquired cellular resistance to cisplatin may be associated with increased gene-specific DNA repair efficiency of a specific lesion, the interstrand cross-link.

Blotting, Southern

Dose-intensive induction therapy with cyclophosphamide, cisplatin, and consolidative abdominal radiation in advanced-stage epithelial ovarian cancer.

PURPOSE: The primary goal of this trial was to evaluate the clinical activity of a high-dose cisplatin-based induction regimen for women with advanced-stage ovarian cancer. A secondary goal was to assess the use of whole-abdominal radiation as consolidative therapy in the subset of women left with less than 5 mm residual disease after completion of chemotherapy. PATIENTS AND METHODS: Fifty consecutive patients with newly diagnosed, advanced-stage ovarian cancer received cisplatin 40 mg/m2/d and cyclophosphamide 200 mg/m2/d intravenously (IV) for 5 days, every 4 to 6 weeks. After three to four cycles of chemotherapy, patients who still had residual disease less than 5 mm in greatest diameter at second-look surgery were given whole-abdominal radiotherapy. RESULTS: The overall response rate in 49 patients assessable for response was 61.3% (24.5% pathologic complete responses [pCRs], 32.7% pathologic partial responses [pPRs], and 4.1% clinical partial responses [cPRs]). Median survival for all patients was 23.4 months, and actuarial 4-year survival was 33.7% (95% confidence interval [CI], 21.8% to 48.1%). Multivariate analysis showed stage III and serous histology as independent favorable prognostic factors for survival. Median survival for stage III patients was 36.5 months, with an actuarial 4-year survival of 41.6% (95% CI, 25.5% to 59.6%). Median survival for stage IV patients was 12.0 months, with actuarial 4-year survival of 22.9% (95% CI, 9.5% to 45.5%). The major acute toxicities encountered were myelosuppression and peripheral neuropathy. Patients who received consolidative radiotherapy were at increased risk of developing late-onset enteropathy. CONCLUSIONS: This regimen is active against advanced-stage ovarian cancer, but the associated toxicity is severe. Consolidative whole-abdominal radiation did not appear to prolong survival in the subset of women left with less than 5 mm residual disease after chemotherapy.

Adolescent

Phase I study of taxol and granulocyte colony-stimulating factor in patients with refractory ovarian cancer.

PURPOSE: To increase the taxol dose beyond the current standard dose intensity of 175 mg/m2 per 21 days in patients with refractory ovarian cancer. PATIENTS AND METHODS: Fifteen patients who had platinum-refractory or recurrent advanced-stage ovarian cancer were treated with taxol in a phase I trial and were given granulocyte-colony stimulating factor (G-CSF). Taxol was administered at doses of 170, 200, 250, and 300 mg/m2 every 3 weeks. G-CSF was given as a daily subcutaneous injection that started 24 hours after the completion of the taxol infusion. RESULTS: Four patients required either taxol dose reduction or delay. The dose-limiting toxicity (DLT) was peripheral neuropathy, and it occurred at 300 mg/m2. This toxicity was manifested clinically as a stocking-and-glove sensory disturbance that primarily affected proprioception, and was associated with objective changes on nerve conduction studies in affected individuals. Mucositis was rarely observed. Substantial myelosuppression was observed, but was not dose-limiting. Five of 14 assessable patients experienced an objective response to therapy, with another five individuals who experienced a 30% to 45% reduction in tumor mass. CONCLUSION: Taxol can be safely administered in doses up to 250 mg/m2 with G-CSF support, which may make it possible to study taxol dose intensification.

Adult

Cisplatin-DNA damage and repair in peripheral blood leukocytes in vivo and in vitro.

We have extended our studies on the relationship between cisplatin/carboplatin-induced DNA damage in readily accessible tissue(s) and clinical response to therapy. Such an approach may assist in the study of cancer drug resistance and in establishing parameters for assessing human populations for sensitivity to DNA damaging agents in the environment. Platinum-DNA adduct levels were measured by atomic absorbance spectrometry. DNA repair capacity was assessed in human T-lymphocytes by the ability to repair cisplatin lesions in cellular DNA or in transfected plasmid DNA. In a "blinded" study of 21 patients receiving combination cisplatin/carboplatin drug therapy, there was a direct relationship between DNA damage in leukocytes and disease response (summary two-sided p = 0.00011). The cohort of patients had 15 different tumor types, suggesting that blood tissue and tumor tissue of an individual may process platinum-DNA damage similarly regardless of the tissue of origin of the tumor. In leukocytes in vivo, persistence and accumulation were prominent features of the cisplatin-DNA adduct profile. Functional DNA repair capacity has been studied in eight human leukocyte cell lines in vitro (three, T-cells; three, B-cells; one, monocytic; one, promyelocytic), using a host cell reactivation assay with cisplatin-damaged pRSVcat. In the three T cell lines studied, host cell reactivation efficiency was directly related to the cells' abilities to repair cisplatin-damaged cellular DNA (correlation coefficient = 0.993).(ABSTRACT TRUNCATED AT 250 WORDS)

Carboplatin

Cisplatin.

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Animals

Effect of anti-HLA and anti-idiotypic antibodies on the long-term survival of heart and kidney allografts.

Long-term survival of heart and kidney allografts is threatened by the development of chronic rejection. Analysis of the relationship between reversible acute rejection episodes and actuarial survival at 5 years showed an inverse correlation suggesting that early cellular events may trigger antibody-mediated chronic rejection. In both heart and kidney allograft recipients producing anti-HLA antibodies we found a significant decrease in the 5-year graft survival rate. However, there was heterogeneity among anti-HLA antibody producers with respect to the development of anti-idiotypic antibodies. The actuarial 5-year graft survival was significantly higher in patients with Ab2 compared to patients without.

Actuarial Analysis

Effect of recipient gender and race on heart and kidney allograft survival.

Study of long-term survival of heart allografts shows that AA males and females have lower graft survival rates than those observed in NAC recipients. Primary kidney allografts in AA males, but not females, also display lower 5-year survival rates compared to those observed in the corresponding populations of NAC. Comparison of graft survival in the overall population of male and female recipients of kidney allografts shows that females have higher graft survival rates, probably as a result of better HLA matching. The level of alloantibody activity in posttransplantation sera is similar in the two populations, suggesting that factors other than HLA mismatching may contribute to the higher degree of graft failure in AA recipients.

Actuarial Analysis