Isolation of membrane attack complex of complement from myelin membranes treated with serum complement.

The interaction between complement and myelin membranes and its possible role in myelin damage and in the disposal of damaged myelin in vivo is of interest because activation of complement generates both opsonin(s) and membrane attack complex of complement. In our studies on the role of complement in demyelination, we have shown that isolated myelin activates serum complement in the absence of myelin-specific antibody and that membrane attack complex of complement is the required factor in antibody-mediated demyelination of mouse cerebellar explant cultures. In the present study, we examined whether activation of serum complement by myelin is associated with the formation of membrane attack complex of complement in myelin membranes.

Small cell lung cancer 1973-1983: early progress and recent obstacles.

The recognition that the vast majority of patients with small cell lung cancer have distant metastatic disease at the time of diagnosis led to the use of systemic chemotherapy and consequent major improvements in survival in the early to mid-1970's. In the past five years, however, the pace of therapeutic advances has slowed. Recently evaluated treatment strategies, including more intensive induction chemotherapy, "late intensive" therapy of responding patients, alternation of chemotherapeutic regimens, integration of chest irradiation with drug therapy, large field irradiation, and reappraisal of the value of surgical resection, are discussed in this review.

Heterogeneity among microtubules of the cytoplasmic microtubule complex detected by a monoclonal antibody to alpha tubulin.

Three monoclonal antibodies specific for tubulin were tested by indirect immunofluorescence for their ability to stain cytoplasmic microtubules of mouse and human fibroblastic cells. We used double label immunofluorescence to compare the staining patterns of these antibodies with the total microtubule complex in the same cells that were stained with a polyclonal rabbit antitubulin reagent. Two of the monoclonal antitubulin antibodies bound to all of the cytoplasmic microtubules but Ab 1-6.

Initiation of proliferative events by human alpha-thrombin requires both receptor binding and enzymic activity.

To determine the role of thrombin high-affinity receptor occupancy and enzymic activity in thrombin initiation of cell proliferation, we have utilized thrombin derivatives which separate these functions. We previously showed that enzymically active gamma-thrombin stimulates ion fluxes without binding to high-affinity sites, whereas proteolytically inhibited DIP-alpha-thrombin which binds to high-affinity receptors does not. Since neither derivative initiates DNA synthesis by itself, this suggested that two separate sequences of events might be necessary for a complete initiation signal.

Immunofluorescent visualization of specifically bound thrombin reveals cellular heterogeneity in number and density of preclustered receptors.

Thrombin binding to formaldehyde-fixed mouse embryo (ME) cells was visualized by indirect immunofluorescence as a dot-like pattern with dots of approximately 500 nm diameter located over the entire cell surface. Experiments comparing the binding of 125I-thrombin and dot appearance on parallel cultures indicate that the immunofluorescent pattern is specific for thrombin-binding to high-affinity receptors. Similar patterns were observed on cells fixed in ethanol or glutaraldehyde prior to thrombin binding and on cells maintained at 4 degrees C.

Treatment of extensive stage small cell bronchogenic carcinoma. Effects of variation in intensity of induction chemotherapy.

Forty-nine consecutive previously untreated patients with extensive stage small cell bronchogenic carcinoma were treated with cyclophosphamide 1,000 mg/m2, doxorubicin 50 mg/m2, etoposide (VP-16-213) 125 mg/m2, and vincristine 1.4 mg/m2 (maximum 2 mg) as induction chemotherapy. Thirty-four patients were given high-intensity therapy, receiving these drugs on both Days 1 and 8 of two or three 21-day induction courses.

High-dose methotrexate with leucovorin rescue in patients with unresectable non-small cell carcinoma of the lung.

Thirty-one patients with unresectable non-small cell carcinoma of the lung (19 adenocarcinoma, 7 large cell carcinoma, 4 squamous cell carcinoma, 1 mixed histology) were treated with one of two intravenous infusion schedules of high dose methotrexate with leucovorin rescue. First, 14 patients received methotrexate in escalating doses from 1.5 to 12 g/m2 over 6 hours followed immediately with leucovorin 15 mg/m2 for 12 doses every 6 hours; there were no complete or partial responses among these 14 patients.

Amplification and expression of the c-myc oncogene in human lung cancer cell lines.

Genetic changes involving the c-myc oncogene have been observed in human tumours. In particular, the c-myc gene is translocated in Burkitt's lymphoma and is amplified in the human promyelocytic leukaemia cell line, HL-60, which contains double minute chromosomes (DMs). More recently, an amplified c-myc gene has been positioned on a chromosomal homogeneous staining region (HSR) in a human colon cancer cell line, COLO 320, with neuroendocrine properties.

Demonstration of a late amiloride-sensitive event as a necessary step in initiation of DNA synthesis by thrombin.

Amiloride, a Na+ influx inhibitor, has been shown to inhibit initiation of DNA synthesis by thrombin in mouse embryo fibroblast-like cells. Long exposures (24 hr) to high concentrations of amiloride inhibited incorporation of thymidine into the DNA of both thrombin-stimulated and nonstimulated cells, suggesting that this inhibition might not be specific for thrombin-initiated DNA synthesis. Fluorescence microscopy and spectrofluorimetry showed that amiloride was internalized with an apparent mitochondrial association and that the internalized amiloride was readily released from the cells after removing amiloride from the medium.

Hormone supplemented media for cloning human breast cancer: increased colony formation without alteration of chemosensitivity.

We tested the ability of hormones and growth factors to enhance the colony formation in soft agarose of breast carcinoma using two human breast carcinoma cell lines, MCF-7 and MDA-MB231, MCF-7 could clone in a basal medium supplemented only by insulin, transferrin, prostaglandin F2 alpha, and fibronectin. Combining oestradiol, dexamethasone, insulin, transferrin, and triiodothyronine with a basal medium supplemented with 5% (v/v) foetal bovine serum (FBS) increased colony forming efficiency (CFE) two-to three-fold over the best obtained in serum supplemented medium without hormones. While optimal CFE was seen in the hormonally supplemented medium plus 5% FBS, clonal anchorage independent growth could also be obtained without serum for both cell lines by substituting 0.

Diagnostic and biological implications of flow cytometric DNA content analysis in lung cancer.

Flow cytometric DNA content analysis, performed on clinical specimens from patients with lung cancer, was compared with clinical features, histological and/or cytological examination of the same specimen and, in some instances, to chromosome analysis and repeat DNA content analysis of short-term cultures. Tumors from 85% of non-small cell and 83% of small cell lung cancer patients had aneuploid DNA content; multiple aneuploid stem lines were present in 11% of patients. Comparisons with microscopic examination showed that aneuploid cells were detected in 122 of 167 clinical samples containing tumor cells and in 3 of 177 samples microscopically free of tumor.

Evidence for multidrug-resistant cells in human tumor cell populations.

Data are presented from two cell culture systems which support the notion that a multi-drug-resistant phenotype occurs in human tumor cell populations. Human small cell lung cancer cell lines derived from patients in relapse following intensive combination chemotherapy demonstrate broad cross-resistance to nine standard drugs in vitro. However, analysis of [14C]glucosamine-labeled glycoproteins in the small cell lung cancer cell lines failed to identify any consistent association between a specific glycoprotein marker and the drug-resistant phenotype.

Bombesin-like peptides and receptors in human tumor cell lines.

Human cancer cell lines were assayed for bombesin-like peptides and receptors. Acid extracts derived from small cell lung cancer, but not other types of cancer had high levels of immunoreactive bombesin. Regardless of patient treatment, site of tumor origin (bone marrow, lymph node, or pleural effusion) or culture conditions, small cell lung cancer cell lines had high levels of bombesin-like peptides.

Monoclonal antibodies that distinguish non-small cell from small cell lung cancer.

Two murine IgG2Ak monoclonal antibodies (703D4, 704A 1) were produced and characterized after immunization with a human large cell lung cancer line (NCI-H 157). These antibodies detect different epitopes on 31 kilodalton [35S]methionine incorporating protein(s). Radiobinding and immunohistochemical studies show these antibodies bind to most (11/13) human non-small cell lung cancer (adenocarcinoma, epidermoid, and large cell), but not to small cell lung cancer (0/11) tumors tested.

In vitro radiation and chemotherapy sensitivity of established cell lines of human small cell lung cancer and its large cell morphological variants.

The in vitro response to radiation and chemotherapeutic drugs of cell lines established from 7 patients with small cell (SC) lung cancer were tested using a soft agarose clonogenic assay. Five cell lines retained the typical morphological and biochemical amine precursor uptake decarboxylation characteristics of SC, while two cell lines had undergone "transformation" to large cell (LC) morphological variants with loss of amine precursor uptake decarboxylation cell characteristics of SC. The radiation survival curves for the SC lines were characterized by D0 values ranging from 51 to 140 rads and extrapolation values (n) ranging from 1.

Small-cell carcinoma of lung: reinduction therapy after late relapse.

Some patients with small-cell carcinoma of lung can be expected to achieve long-term disease-free survival. However, relapses may occur even after 2 years. Information on the treatment of these patients is sparse, although response rates to "salvage" therapy in patients with progressive disease while receiving treatment are poor.

Phase II trial of aziridinylbenzoquinone (AZQ) in patients with refractory small cell carcinoma of the lung.

Sixteen previously treated patients received AZQ in a phase II study to test therapeutic efficacy in refractory small cell lung cancer. The dose and schedule of AZQ was 20 mg/m2 day 1 and 8, with treatments repeated every 28 days. No objective responses were noted among 16 evaluable patients.

Calcitonin secretion by continuous cultures of small cell carcinoma of the lung: incidence and immunoheterogeneity studies.

A study was made of immunoreactive calcitonin (iCT) secretion by continuous cultures of small cell carcinoma of the lung (SCCL). Using an antiserum region specific for the midportion of the molecule, 9/12 cultures were found to secrete iCT. Gel filtration studies were performed on both supernatant fluid (SF) and cell pellet (CP) extract from a culture secreting high levels of iCT.

Fatal hypereosinophilia with chromosome 15q- in a patient with multiple primary and familial neoplasms.

A man with large-cell carcinoma of the lung, cerebral meningioma, occult adenocarcinoma of the prostate, and follicular adenoma of the thyroid developed symptomatic, rapidly progressive hypereosinophilia with abnormalities of eosinophil ultrastructure and bone marrow karyotype (45,X,15q22-). Although the patient's eosinophilia defied strict classification as idiopathic hypereosinophilic syndrome (HES), simple tumor-associated eosinophilia, or eosinophilic leukemia, it appeared to be incited by the lung cancer and quickly acquired malignant independence. The family had an excess of prostate cancer and lymphoproliferative neoplasms.

The clinical behavior of "mixed" small cell/large cell bronchogenic carcinoma compared to "pure" small cell subtypes.

Biopsy specimens from 19 previously untreated lung cancer patients were prospectively diagnosed as small cell carcinoma with a large cell component. The patients were thoroughly staged and received intensive combination chemotherapy. They represented 12% of all small cell carcinoma cases eligible for aggressive chemotherapy protocols during a 5.