Lipid metabolism in human platelets. I. Evidence for a complete fatty acid synthesizing system.

Extracts from human platelets contain the enzymes of de novo fatty acid biosynthesis. The pattern of incorporation of acetate-1-(14)C into fatty acids by intact platelets indicates that these enzymes function in platelets. The level of acetyl-coenzyme A (CoA) carboxylase activity in extracts of platelets from normal subjects is 0.036 +/-0.01 mmumole of malonyl-CoA formed per min per mg of protein and that of fatty acid synthetase is 0.075 +/-0.016 mmumole of malonyl-CoA utilized per min per mg of protein. Thus, platelets are the only formed elements of the blood capable of de novo fatty acid synthesis. The capacity of platelets to synthesize fatty acids is similar to human liver based on enzyme activity per milligram of soluble protein.Acetyl-CoA carboxylase was purified 16-fold from platelet extracts, and this partially purified enzyme was compared to enzyme from rat liver. The two enzymes were similar with respect to requirements, substrate affinities, pH profile of activity, inhibition by malonyl-CoA, and aggregation in the presence of citrate. Thus, while fatty acid synthesis may serve a different function in platelets than in liver, the properties of acetyl-CoA carboxylase from these tissues are alike. The levels of the enzymes of fatty acid synthesis were significantly higher in platelets from splenectomized subjects than in controls. Acetyl-CoA carboxylase levels were 0.086 +/-0.027 mmumole of malonyl-CoA formed per min per mg of protein, and fatty acid synthetase levels were 0.151 +/-0.039 mmumole of malonyl-CoA utilized per min per mg of protein. These changes in the enzymes of fatty acid synthesis occurred promptly after splenectomy with peak values being reached within 7-10 days.

Cellular retinoic acid-binding protein in human lung carcinomas.

Cellular retinoic acid-binding protein (CRABP) was detected in the cytosol of 11 human non-small-cell lung cancer specimens. Neither normal lung nor a small-cell lung cancer specimen contained this binding protein. The quality of CRABP per milligram of cytosol protein ranged from 48.3 to 426.5 fmol.

Interleukin-2 activity in patients with extensive small-cell lung cancer: a phase II trial of Cancer and Leukemia Group B.

BACKGROUND: Chemotherapy may induce overall (complete plus partial) response rates of more than 50% and complete response rates up to 25% in extensive small-cell lung cancer (stage IIIB or IV), but survival is generally limited to 8-12 months. Interleukin-2 (IL-2) has demonstrated activity against this disease in vitro and has produced regression in melanoma and renal cell carcinoma. PURPOSE: The purpose of this study was to determine in a prospective, nonblinded, phase II trial the activity of IL-2 in patients with extensive small-cell lung cancer who had not achieved complete remission with chemotherapy. METHODS: The 68 patients eligible for the study were initially treated with at least one dose of combination chemotherapy with cisplatin, doxorubicin, cyclophosphamide, and etoposide (PACE). Of the 50 who did not obtain complete remission with PACE, 24 who had measurable or evaluable disease and whose medical condition allowed further therapy were treated with IL-2. Beginning 3 weeks after the last dose of PACE, IL-2 was administered intravenously at 4.5 million Nutley units/m2 per day as a continuous infusion for 96 hours, followed by a 3-day rest. The planned duration of therapy was 8 weeks. RESULTS: Of the 24 patients eligible to receive IL-2, four (17%) with measurable disease or evaluable but not measurable disease obtained a complete response after IL-2 therapy; one (4%) patient had a partial response. The overall response rate was 21%. Complete responses continued for 8, 9, and more than 11 months in three patients; the remaining patient developed acute myelomonocytic leukemia while in complete remission approximately 8 months after the start of IL-2 therapy. Only five of the 24 patients were able to complete the planned 8 weeks of IL-2 therapy. Therapy was discontinued in 11 patients because of life-threatening side effects, in six because of disease progression, and in two who withdrew from the study, probably related to IL-2 toxicity. CONCLUSIONS: These results indicate that IL-2 has some activity in extensive small-cell lung cancer and suggest that IL-2 is not cross-resistant with PACE therapy. IMPLICATIONS: Further studies are needed to define the optimum timing, dose, and schedule of IL-2 and to determine whether the agent has a role in the therapy of small-cell lung cancer.

Phase I study and pharmacokinetics of weekly high-dose 13-cis-retinoic acid.

In an attempt to increase the peak plasma levels of 13-cis-retinoic acid (13-cis-RA) and its efficacy in vivo, a Phase I study and pharmacokinetics of weekly high-dose, oral 13-cis-RA was conducted in 23 cancer patients who were refractory to conventional treatments. At 200 mg/sq m, the mean peak plasma level of 13-cis-RA was 1.5 +/- 0.1 (SE) micrograms/ml; at 400 mg/sq m, the mean peak plasma level increased to 3.8 +/- 0.7 micrograms/ml. Further increases of the 13-cis-RA dose up to 1800 mg/sq m did not lead to proportional increases in either the mean peak plasma levels or area under the curve, indicating a saturable absorption phenomenon. The terminal half-life was highly variable (range, 2.8 to 101.3 h) and was not related to the dose given. A secondary peak plasma concentration was seen in five patients, suggesting enterohepatic circulation. The toxicities such as headache, cheilitis, dry skin, and dry eyes were frequent on the weekly schedule but were not dose-limiting. One patient had an elevation of the triglycerides of 2 to 5 times the upper limit of normal; five patients had an elevation of 1.1 to 2 times normal. No objective responses were observed to treatment with 13-cis-RA. Of 20 patients receiving an adequate trial of the drug, 18 showed progression of their cancer, and two had stable disease.

Establishment and characterization of four new human non-small cell lung cancer cell lines.

Four new human non-small cell lung cancer cell lines have been established in vitro. These cell lines have been characterized by (a) growth of a tumor in nude mice with histopathology similar to that of the primary, (b) isoenzyme patterns phenotypically human and distinct from each other, (c) distinguishing karyotypic findings, (d) growth rate determinations, and (e) presence of epidermal growth factor receptors. Each of the cell lines will form colonies when directly seeded into a flask without soft agar. The development and availability of the four cell lines may facilitate in vitro studies of the biology of this common cancer. Their clonogenic potential may be of value in the study of sensitivity to antineoplastic agents. Their low passage level may mean that their antigens still resemble those of the primary tumor.

Limited impact of total parenteral nutrition on nutritional status during treatment for small cell lung cancer.

During a randomized trial of total parenteral nutrition (TPN) in patients with small cell lung cancer, we evaluated the short- and long-term effects of 4 weeks of TPN on nutritional assessment parameters. All 119 patients who were accrued to the study received the same chemotherapy and radiotherapy protocol which extended over a 1-year period: 57 patients received TPN; and 62 served as controls. At base line, patients with greater than 5% pretreatment weight loss had significantly lower levels of serum albumin, total iron-binding capacity, and creatinine/height index. TPN administration led to a significant increase in mean caloric intake and weight compared with controls (P less than 0.0001). In the short-term study, body fat, as measured by triceps skinfold thickness, was maintained, and there was a small increase in arm muscle circumference. Serum albumin and hematocrit decreased but promptly returned to pretreatment levels when TPN was stopped. There were no long-term differences in any of the nutritional assessment parameters between the two groups.

Radiosensitization with carboplatin for patients with unresectable stage III non-small-cell lung cancer: a phase III trial of the Cancer and Leukemia Group B and the Eastern Cooperative Oncology Group.

PURPOSE: To determine whether the administration of carboplatin concurrently with radiation treatment improves survival in patients with inoperable stage III non-small-cell lung cancer. PATIENTS AND METHODS: Two hundred eighty-three patients with inoperable stage III non-small-cell lung cancer were entered onto a randomized trial by the Cancer and Leukemia Group B and the Eastern Cooperative Oncology Group. Randomization was performed before initiation of any therapy. All patients received an induction chemotherapy program with vinblastine and cisplatin for 5 weeks, followed by 6,000 cGy of radiation therapy over 6 weeks. One hundred thirty-seven patients were randomized to this therapy regimen alone; 146 patients were randomized to receive carboplatin at 100 mg/m2/wk concurrent with the radiation therapy. RESULTS: The complete response was 18% with concurrent carboplatin versus 10% with radiotherapy alone (P = .101). There was no difference with respect to failure-free survival (10% with carboplatin and 9% with radiotherapy alone) or overall survival (13% with carboplatin and 10% with radiotherapy alone) at 4 years. In patients not receiving carboplatin, the relapse rate was 69% within the field of radiation and 53% in the boost volume. In patients receiving carboplatin, the relapse rate was 59% within the field of radiation and 43% in the boost volume. Patients with cancers more than 70 cm2 in size had significantly poorer survival (P = .01). CONCLUSION: Carboplatin at the dose and schedule used did not significantly impact on disease control or survival. The relapse rate within the chest remained more than 50%. More effective regimens will be required to impact on local disease control and survival.

Effects of intravenous hyperalimentation during treatment in patients with small-cell lung cancer.

One hundred nineteen patients were entered onto a randomized trial of the role of intravenous hyperalimentation (IVH) in patients with small-cell lung cancer. IVH was given during the first 30 days of induction chemotherapy to 54 patients. IVH did not effect any improvement in response or survival from therapy. In view of the lack of benefits from IVH, an analysis was made of the toxicities suffered by the 54 patients receiving IVH as well as any effects IVH might have made on chemotherapy-induced toxicity. Toxicities observed included mechanical difficulties with the catheter leading to temporary or permanent discontinuation of the IVH (11 patients), subclavian vein thrombosis (one patient), sepsis in nine patients v none of the 62 control patients, fluid overload (27 patients), hyponatremia (25 patients), and hyperglycemia requiring insulin (13 patients). Patients receiving IVH had higher granulocyte counts on days 14 and 21 of the first cycle of chemotherapy. Analysis shows that this difference is likely caused by fever and infection associated with IVH rather than any nutritional effect on granulopoiesis. In this population of patients, IVH had significant complications but did not ameliorate chemotherapy-induced toxicity and it did not effect any clinical benefit. Future studies of adjunctive nutritional therapy must consider the significant risk in this older population and must limit IVH volume or exclude patients with even mild compromise in cardiovascular functions. Further, any new trial must have a significant rationale for adjunctive use to justify the potential risks.

Randomized trial of vinorelbine compared with fluorouracil plus leucovorin in patients with stage IV non-small-cell lung cancer.

PURPOSE: This prospective randomized trial was performed to compare the effectiveness of intravenous vinorelbine tartrate with intravenous fluorouracil and leucovorin (5-FU/LV) on the primary end points of survival, quality of life (QOL), and relief of cancer-related symptoms in patients with advanced non-small-cell lung cancer (NSCLC). Secondary end points included tumor response rates and time to treatment failure. In addition, the safety of both treatment regimens was evaluated in this multicenter study. PATIENTS AND METHODS: Two hundred sixteen patients with stage IV NSCLC were enrolled onto this study from 18 centers. Vinorelbine was administered at a dose of 30 mg/m2/wk. 5-FU/LV was administered at a dose of 425 mg/m2 and 20 mg/m2, respectively, for 5 consecutive days every 4 weeks. Patients with progressive disease or toxicity were removed from study while responding and stable patients were continued on therapy. RESULTS: The median survival time of patients who received vinorelbine was 30 weeks, with 25% of patients alive at 1 year, compared with a median survival time of 22 weeks and 16% of patients alive at 1 year for those treated with 5-FU/LV (P = .03, log-rank test). This improvement in survival was associated with a higher objective response rate (12% v 3%) and time to treatment failure (10 weeks v 8 weeks) for vinorelbine versus 5-FU/LV. The dose-limiting toxicity of vinorelbine was granulocytopenia, with 54% of patients experiencing grade 3/4 granulocytopenia. Nonhematologic toxicity of vinorelbine was generally grade 1 or 2. The most common grade 3 toxicities were related to injection-site reactions. CONCLUSION: This trial confirms the efficacy of vinorelbine in patients with advanced NSCLC. The clinical activity and relatively favorable toxicity profile of this agent make it a reasonable and useful treatment option in the management of patients with this disease.

Phase I clinical study of fish oil fatty acid capsules for patients with cancer cachexia: cancer and leukemia group B study 9473.

The purpose of this study was to determine the maximum tolerated dose and dose-limiting toxicities of fish oil fatty acid capsules containing omega-3 fatty acid ethyl esters. Twenty-two patients with neoplastic disease not amenable to curative therapy who had lost 2% of body weight over a previous 1 month time period were given an escalating dose of fish oil fatty acids. The maximum tolerated dose was found to be 0.3 g/kg per day of this preparation. This means that a 70-kg patient can generally tolerate up to 21 1-g capsules/day containing 13.1 g of eicosapentaenoic acid + docosahexaenoic acid, the two major omega-3 fatty acids. Dose-limiting toxicity was gastrointestinal, mainly diarrhea, and a poorly described toxicity designated as "unable to tolerate in esophagus or stomach." A patient with chronic lymphocytic leukemia taking the fish oil provided an unusual opportunity to perform a detailed biochemical study of the effect of fish oil capsules on the lipids of malignant cells at several sequential time points in treatment. Studies of the malignant lymphocytes, serum, and whole blood of this one patient revealed an increase in eicosapentaenoic acid, the major component of the fish oil capsules, during fish oil capsule treatment. This study provides a scientific basis for the selection of omega-3 fatty acid doses for future studies in cancer. The maximum tolerated dose found is considerably higher than anticipated from published studies of many human diseases. The observation of a modification of the lipids of leukemic cells, serum, and blood in a patient with chronic leukemia provides a biochemical basis for a possible effect of fish oil supplements on cancer cachexia and tumor growth.

Myasthenic syndrome and small cell cancer of the lung. Variable response to antineoplastic therapy.

Myasthenic syndrome secondary to small cell lung cancer has been studied in five patients who achieved complete remission with chemotherapy. The relationship between response or relapse of the neoplasm to therapy and the activity of the myasthenic syndrome is variable. This inconsistent clinical correlation between the cancer and its paraneoplastic syndrome is examined in view of current data on the immunologic basis of myasthenic syndrome.

Diagnosis of major depression in cancer patients according to four sets of criteria.

Diagnoses of major depression in 152 cancer patients differed as much as 13% depending on the diagnostic system used. The Beck Depression Inventory and the Hamilton Rating Scale for Depression were useful tools for screening patients with depressive symptoms but frequently misclassified those who had no major depression according to one or more of the criteria-based diagnostic systems.

A phase II study evaluating the efficacy of carboplatin, etoposide, and paclitaxel with granulocyte colony-stimulating factor in patients with stage IIIB and IV non-small cell lung cancer and extensive small cell lung cancer.

We initiated a phase II pilot study to determine whether adding paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) to combination carboplatin/etoposide is tolerable and active in patients with advanced non-small cell lung cancer and extensive small cell lung cancer. Patients were given carboplatin (area under the concentration-time curve of 6) followed by etoposide 80 to 100 mg/m2 intravenously on days 1 through 3 followed by paclitaxel 200 mg/m2 intravenously over 3 hours on day 3. On days 4 through 18, granulocyte colony-stimulating factor 5 microg/kg was administered subcutaneously. Each cycle was repeated every 21 days. Fourteen patients have been accrued to the study and 12 were evaluated for toxicity, the first 10 of whom were treated with 80 mg/m2 etoposide. Among the first 10 evaluable patients, significant grade 4 neutropenia occurred in one patient, grade 4 thrombocytopenia in three patients, grade 2 neuropathy in two patients, and grade 3 neurotoxicity in two patients. None of the four patients with non-small cell lung cancer responded to treatment, while six of seven small cell lung cancer patients have obtained major responses to therapy. We have increased the etoposide dose to 100 mg/m2 in subsequent patients. The combination chemotherapy regimen of carboplatin, etoposide, and paclitaxel is tolerable and active in patients with small cell lung cancer.

Nonoperative management of non-small cell lung cancer: the current cancer and leukemia group B experience.

The Cancer and Leukemia Group B (CALGB) is studying nonoperative management in two subgroups of patients with advanced non-small cell lung cancer. In patients with regional disease, primarily those with bulky N2 or T4 disease or those with contralateral mediastinal involvement (N3), a phase III trial is under way to explore concurrent carboplatin as intensification of local therapy and additional systemic treatment. This builds on prior CALGB work demonstrating the benefits of induction chemotherapy prior to radiation for selected patients with stage III disease. For patients with still more advanced disease, a trial evaluating efficacy and cost of two supportive care modalities during intensive chemotherapy is about to begin accrual. Following its completion, the CALGB plans to evaluate new chemotherapy combinations based on one or more of the exciting new agents now being tested for the nonoperative management of non-small cell lung cancer.

Carboplatin in non-small cell lung cancer: an update on the Cancer and Leukemia Group B experience.

Since 1984, the Respiratory Committee of the Cancer and Leukemia Group B (CALGB) has evaluated carboplatin, either alone or in combination, in five separate phase II studies for patients with inoperable non-small cell lung cancer (NSCLC). All patients had an Eastern Cooperative Oncology Group performance status of 0 to 2 and had not received previous treatment with chemotherapy. In 70 patients with stage IIIB or IV disease, carboplatin 400 mg/m2 administered intravenously once every 4 weeks produced a 16% overall response rate and an acceptable toxicity profile. Subsequently, combinations of carboplatin/cisplatin, carboplatin/etoposide, and carboplatin/vinblastine have been evaluated in similar patient groups. Response rates of 11%, 12%, and 20%, respectively, were obtained. Myelosuppressive toxicity was substantially greater with carboplatin/etoposide and carboplatin/vinblastine than with carboplatin alone. Carboplatin/vinblastine demonstrated efficacy similar to that of the cisplatin/vinblastine combination previously evaluated by CALGB for treatment of similar patients with advanced NSCLC; ease of administration and lack of significant nephrotoxicity also compared favorably with cisplatin-based therapy. In regional NSCLC patients, carboplatin 100 mg/m2/wk can be administered intravenously concurrently with 60 Gy thoracic radiotherapy given over 6 weeks. The impact of concurrent carboplatin added to a sequential chemotherapy-radiotherapy program for patients with regional NSCLC is currently under study by the CALGB Respiratory Committee.

Management of primary mediastinal seminoma.

Radiation therapy has been the usual initial treatment for mediastinal seminoma in the past. However, 25 to 40 percent of patients are not cured by this therapy, and other therapy is needed. Review of case reports show that vinblastine, bleomycin, and cis-platinum are effective therapy for metastatic disease, advanced disease within the chest, or mixed germ cell tumors with nonseminomatous elements. The use of tumor markers and chemotherapy must be integrated into the staging of and therapy for primary mediastinal seminoma.

Subcutaneous interleukin-2 as initial therapy for patients with extensive small cell lung cancer: a phase II trial of Cancer and Leukemia Group B.

In a prior Cancer and Leukemia Group B (CALGB), 16% of a small cohort of patients with extensive small call lung cancer who had failed to obtain a complete remission with chemotherapy did obtain a complete remission after therapy with interleukin-2 (IL-2). In this current trial, 10 patients with extensive small cell lung cancer who had had no prior therapy were treated with subcutaneous IL-2 as induction therapy and then standard chemotherapy with etoposide/cisplatin. Only one patient experienced an objective response to the IL-2 administered prior to chemotherapy. The factors governing response to IL-2 in the first trial but not in this trial are discussed.

A randomized phase II study of ifosfamide/mesna/cisplatin plus G-CSF or etoposide/cisplatin plus G-CSF in advanced non-small cell lung cancer: a Cancer and Leukemia Group B study.

This Phase II study was designed to determine the efficacy of two chemotherapy regimens with G-CSF support for patients with advanced non-small cell lung cancer (NSCLC). One-hundred and one patients with Stage IIIB or IV NSCLC and performance status 0-1 were randomized to receive ifosfamide 2.0 g/m2 days 1-3, mesna 400 mg/m2 at 0, 4, 6 h days 1-3, cisplatin 33 mg/m2 days 1-3 or etoposide 200 mg/m2 days 1-3, cisplatin 35 mg/m2 days 1-3. Both groups received G-CSF 5 micrograms/kg SQ day 4 to the post day 11 absolute neutrophil count > 10 000. For the 47 eligible patients receiving ifosfamide/mesna/cisplatin, the response rate was 26% (95% confidence interval: 14-40%) and the median survival 7.5 months (95% confidence interval: 5.8-11.0 months). Grade 3 or worse toxicities were: neutropenia 75%, thrombocytopenia 70%, infection 21%. There were two treatment-related deaths due to infection. For course 1, the median absolute neutrophil count nadir was 1.3, platelet nadir 96 000 and incidence of febrile neutropenia 16%. For the 48 eligible patients receiving etoposide/cisplatin, the response rate was 21% (95% confidence interval: 11-35%) and median survival 5.8 months (95% confidence interval: 4.5-9.7 months). Grade 3 or worse toxicities were: neutropenia 90%, thrombocytopenia 58%, infection 29%. There were three treatment-related deaths due to infection. For course 1, the median absolute neutrophil count was 0.2, platelet nadir 80 000 and incidence of febrile neutropenia 33%. For both ifosfamide/mesna/cisplatin and etoposide/cisplatin, median duration of Grade IV neutropenia was short (< or = 4 days), time to subsequent courses 21 days and dose delivered > 95% of planned dose. Although G-CSF allowed full doses of drugs to be delivered on schedule, both ifosfamide/mesna/cisplatin and etoposide/cisplatin produced response rates and survival similar to other cisplatin-based regimens. In view of the significant cost of G-CSF and no obvious improvement in response rate, survival or toxicity profile, G-CSF cannot be recommended with these chemotherapy regimens for patients with advanced NSCLC.

Etoposide (VP-16) and cisplatin at maximum tolerated dose in non-small cell lung carcinoma: a Cancer and Leukemia Group B study.

A multi-institutional cooperative group trial was undertaken by the Cancer and Leukemia Group B (CALGB) to evaluate the efficacy of the combination of cisplatin and intravenous etoposide for the treatment of metastatic or recurrent non-small cell lung cancer (NSCLC). The doses used were those previously determined to be the maximally tolerated dose of this drug combination. Forty patients were entered into the trial, 37 of whom were eligible for evaluation. Cisplatin (35 mg/M2/day for 3 days) and etoposide (200 mg/M2/day for 3 days) were administered every 28 days for a planned 6 cycles of therapy. Sixteen of 37 evaluable patients (43%) responded to therapy. Myelosuppression was the dominant toxicity, with 89% of the patients experiencing grade 4 neutropenia, and nearly half grade 3 or 4 thrombocytopenia. Median survival was 8.5 months, with 30% of the patients alive at 1 year and 10% alive at 2 years. Malaise, fatigue, and peripheral neuropathy were the other major toxicities. The combination of etoposide at the dose of 200 mg/M2/day for 3 days and cisplatin at 35 mg/M2/day for 3 days is a highly potent combination against metastatic non-small cell carcinoma.

A phase I/II trial of etoposide and cisplatin in extensive small cell lung cancer: a cancer and leukemia group B study.

Patients with untreated extensive small cell lung cancer (SCLC) with CALGB performance scores 0-2 were treated with etoposide 200 mg/m2/day on days 1-3 and cisplatin doses of 20, 30, or 35 mg/m2/day days 1-3 in a Phase I/II format. Of the nine patients treated at the 35 mg/m2/day cisplatin dose in the Phase I portion of the study, Grade 4 leukopenia occurred in five patients and Grade 4 thrombocytopenia in four. There were two deaths due to myelosuppression and sepsis. This dose was thus considered the maximum tolerated dose (MTD), and a Phase II trial was then conducted using this treatment program. In the Phase II trial of 39 patients, the objective response rate was 67% (95% confidence interval, 50-81%) with 21% complete responses (CI 9-36%). Median survival was 10.5 months. Grade 4-5 leukopenia was seen in 57% and Grade 4-5 thrombocytopenia in 56%. The MTD defined by this Phase I trial represents a 67-100% increase in etoposide and a 32-42% increase in cisplatin dosage compared to prior studies. The observed objective response rates with this regimen are comparable to studies using conventional doses, but hematological toxicity was higher.