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N Tung

Publications and source records attributed to N Tung.

5 recordsLinked to original sources
PubMed2000

BRCA1 and BRCA2 mutation analysis of 208 Ashkenazi Jewish women with ovarian cancer.

Ovarian cancer is a component of the autosomal-dominant hereditary breast-ovarian cancer syndrome and may be due to a mutation in either the BRCA1 or BRCA2 genes. Two mutations in BRCA1 (185delAG and 5382insC) and one mutation in BRCA2 (6174delT) are common in the Ashkenazi Jewish population. One of these three mutations is present in approximately 2% of the Jewish population. Each mutation is associated with an increased risk of ovarian cancer, and it is expected that a significant proportion of Jewish women with ovarian cancer will carry one of these mutations. To estimate the proportion of ovarian cancers attributable to founding mutations in BRCA1 and BRCA2 in the Jewish population and the familial cancer risks associated with each, we interviewed 213 Jewish women with ovarian cancer at 11 medical centers in North America and Israel and offered these women genetic testing for the three founder mutations. To establish the presence of nonfounder mutations in this population, we also completed the protein-truncation test on exon 11 of BRCA1 and exons 10 and 11 of BRCA2. We obtained a detailed family history on all women we studied who had cancer and on a control population of 386 Ashkenazi Jewish women without ovarian or breast cancer. A founder mutation was present in 41.3% of the women we studied. The cumulative incidence of ovarian cancer to age 75 years was found to be 6.3% for female first-degree relatives of the patients with ovarian cancer, compared with 2.0% for the female relatives of healthy controls (relative risk 3.2; 95% CI 1.5-6.8; P=.002). The relative risk to age 75 years for breast cancer among the female first-degree relatives was 2.0 (95% CI 1.4-3.0; P=.0001). Only one nonfounder mutation was identified (in this instance, in a woman of mixed ancestry), and the three founding mutations accounted for most of the observed excess risk of ovarian and breast cancer in relatives.

Adult↗
PubMed2000

Phase I trial of carboplatin, paclitaxel, etoposide, and cyclophosphamide with granulocyte colony stimulating factor as first-line therapy for patients with advanced epithelial ovarian cancer.

OBJECTIVES: The goal of this study was to determine the maximally tolerated doses (MTDs) of carboplatin, paclitaxel (Taxol), etoposide, and cyclophosphamide (CTEC) with granulocyte-colony stimulating factor (G-CSF, Filgrastim) support as first-line chemotherapy in women with advanced epithelial ovarian cancer (EOC). METHODS: Newly diagnosed patients with either stage IV EOC, or stage III EOC and any amount of gross residual tumor after surgical debulking were eligible to receive six cycles of CTEC over five different dose levels in this phase I trial (planned 21-day cycle length). Paclitaxel, carboplatin, and cyclophosphamide were administered intravenously on Day 1, and oral etoposide was administered on Days 1, 2, and 3. G-CSF was administered beginning Day 4. RESULTS: Twenty patients received a total of 98 cycles of CTEC over the five dose levels evaluated. Bone marrow suppression was the major toxic effect, with grade 4 neutropenia and thrombocytopenia being observed in 25 and 23% of cycles, respectively. The overall incidence of febrile neutropenia was 10%, and no toxic deaths occurred. No grade IV thrombocytopenia or febrile neutropenia was observed once the carboplatin dose was reduced from AUC of 7 to 5. Nonhematologic toxicity was generally mild (grade 2 or less). Dose-limiting toxicity was not observed at the highest dose level evaluated in this study, preventing assignment of the MTD. The clinical complete response rate was 92%, although 15 of 16 evaluable patients have progressed with a median progression-free interval of 4 months (range, 2-11 months). One patient remains disease-free 9 months from the completion of CTEC. CONCLUSIONS: The CTEC regimen is well tolerated and highly active. Although the MTD was not reached in this study, the short median progression-free interval suggests that this regimen is unlikely to be superior to standard treatment with paclitaxel and carboplatin. Strategies to optimize the development of future combination chemotherapy regimens in the treatment of newly diagnosed ovarian cancer are discussed.

Adult↗
PubMed1993

Large-cell and immunoblastic lymphoma of the mediastinum: prognostic features and treatment outcome in 57 patients.

PURPOSE: A retrospective study was performed to define clinical characteristics and therapeutic outcome for patients with large-cell and immunoblastic lymphoma of the mediastinum. PATIENTS AND METHODS: Fifty-seven patients who presented with primary, mediastinal large-cell and immunoblastic lymphoma were retrospectively studied to determine initial sites of disease, radiologic characteristics, treatment, outcome, and factors that have prognostic significance for progression-free and overall survival. RESULTS: Fifty-six of the 57 patients had disease that was confined to sites above the diaphragm. Bulky disease and extensive intrathoracic infiltration were common in these patients. All patients were treated with intensive chemotherapy regimens, and 44% of patients received chest irradiation. The overall 5-year survival by Kaplan-Meier estimation was 50% with a freedom-from-relapse rate of 45%. Predictors of disease relapse after chemotherapy included the presence of a pleural effusion (P = .015), a number of involved extranodal sites (P < .01), and a lactic dehydrogenase (LDH) ratio > 3.0 (LDH value/upper limit of assay; P = .04) as well as an incomplete treatment response as evidenced by residual mass on chest radiograph (P = .02) or persistent gallium 67 avidity (P = .01) after chemotherapy. Predictors of decreased survival included the presence of pleural effusion (P = .001), the number of involved extranodal sites (P = .022), and a positive posttreatment 67Ga scan (P = .027). CONCLUSION: Patients with primary mediastinal large-cell and immunoblastic lymphoma have an approximate 50% chance of surviving disease-free after initial therapy. The presence of pleural effusion at presentation was associated with an extremely poor outcome. Bulk disease per se was a negative predictive factor only in patients without pleural effusions when compared with patients who did not have bulk disease. In addition, all patients with involvement of two or more extranodal sites relapsed when treated with standard chemotherapy.

Actuarial Analysis↗
PubMed1991

Cellular myosin heavy chain in human leukocytes: isolation of 5' cDNA clones, characterization of the protein, chromosomal localization, and upregulation during myeloid differentiation.

We have isolated 5' cDNA clones encoding a member of the cellular myosin heavy chain gene family from human leukocytes. The predicted amino acid sequence shows 93% identity to a chicken cellular myosin heavy chain, 76% to chicken smooth muscle, and 40% to human sarcomeric myosin heavy chain. The mRNA is expressed as a 7.4- to 7.9-kb doublet in many nonmuscle cells, and is upregulated in myeloid cell lines on induction from a proliferating to a differentiated state. Antisera raised against a peptide made from the predicted amino acid sequence specifically reacts with a 224-Kd polypeptide in leukocyte cell lines, and the protein is also upregulated during the induction of monocytic and granulocytic differentiation in these cells. The gene for this cellular myosin heavy chain maps to chromosome 22, bands q12.3-q13.1, demonstrating that it is not located in the previously described sarcomeric gene clusters on chromosomes 14 and 17. This cellular myosin heavy chain may be a major contractile protein responsible for movement in myeloid cell lines because no mRNA for sarcomeric myosin heavy chain is detected in these cells.

Amino Acid Sequence↗