Mammalian bombesin-like peptides: neuromodulators of gastric function and autocrine regulators of lung cancer growth

Peptides corresponding closely in structure to the biologically active carboxyl terminal region of the amphibian peptide bombesin have now been isolated from several mammalian species, including man. Two principal forms have been found: one contains 27 amino acids and exhibits variations in amino acid sequence in the amino terminal region; the other is the carboxyl terminal decapeptide and probably does not vary among mammals. These peptides exhibit full immunoreactivity with most bombesin antisera and account for "bombesin-like immunoreactivity" that has been described in mammalian brain, sympathetic ganglia, and nerve fibers in the gut as well as in fetal lung endocrine cells and certain lung tumors, especially small cell lung carcinoma. The name gastrin releasing peptide (GRP) was given to the porcine and avian heptacosapeptides by McDonald and Mutt. The larger and smaller mammalian peptides now often are called GRP27 and GRP10. Both forms exhibit the full spectrum of activity shown by bombesin. Evidence has been obtained that neural release of mammalian bombesin-like peptides is physiologically important in regulation of gastrin release from the stomach. Lung tumors that produce bombesin-like peptides also have receptors for bombesin. These receptors appear to be involved in the autocrine regulation of tumor cell proliferation.

Paraneoplastic syndromes and constitutional symptoms in prediction of metastatic behavior of small cell carcinoma of the lung

Small cell carcinoma of the lung is frequently associated with a paraneoplastic syndrome or constitutional symptoms. To examine correlations between paraneoplastic syndromes or constitutional symptoms and tumor behavior, the clinical and pathologic features were reviewed in 85 patients with small cell carcinoma of the lung who underwent complete autopsy at The Johns Hopkins Hospital between 1962 and 1983. The 28 (33 percent) subjects with a paraneoplastic syndrome survived significantly longer (10.5 +/- 1.5 months) than those without a paraneoplastic syndrome (7.4 +/- 0.7 months) (p less than 0.05), and they had significantly higher frequencies of tumor invasion into major bronchi (p less than 0.01) and more extensive metastases to bone marrow (p less than 0.05), but significantly lower frequencies of and less extensive metastases to the central nervous system (p less than 0.005). The 35 (41 percent) subjects with constitutional symptoms had markedly increased tumor burdens (p less than 0.005) with significantly more extensive metastases to bone marrow, liver, and lungs (all p less than 0.05). The findings suggest that subjects with small cell carcinoma of the lung associated with a paraneoplastic syndrome tend to have a more benign clinical course with prolonged survival; in addition, the significantly lower frequency of central nervous system metastases in these patients may be due to a paucity of the subpopulations of tumor cells that have the propensity to metastasize to the brain. In contrast, it appears that constitutional symptoms develop in patients with small cell carcinoma of the lung because of rapid tumor growth, coupled with impairment of synthetic activity in the liver due to extensive infiltration of tumor into hepatic parenchyma.

Long-term survival and toxicity in small cell lung cancer. Southwest Oncology Group study

In the first study of combined chemotherapy and radiation therapy for small cell lung cancer by the Southwest Oncology Group, 17 patients survived more than five years after treatment was initiated (4.6 percent). Late relapse, or a second primary malignancy three to six years after diagnosis, accounted for death in five of these patients. Late recurrences involved the chest, bone, and liver; none occurred in the central nervous system. Disease-free survival continues in 10 patients (6 percent of those with limited disease and 1 percent of those with extensive-stage diseases) at a minimal follow-up in excess of six years. One definite case of chronic treatment-related toxicity occurred: congestive cardiomyopathy after 450 mg/m2 of doxorubicin, successfully managed with digitalis and diuretics. One severe neurologic problem (orthostatic hypotension with preterminal dementia) and two less severe neurologic complications (occasional falling episodes without documented cause and cerebrovascular accident) may be treatment-related. Progressive pulmonary disability, post-herpetic pain syndromes, organic brain syndrome, and hematologic abnormalities have not been observed to date. Nitrosourea administration and/or co-administration of a nitrosourea or methotrexate during the induction phase of treatment with radiotherapy to the brain may account for the higher incidence of complications observed by others in long-term survivors.

Changes in body composition in patients with small-cell lung cancer. The effect of total parenteral nutrition as an adjunct to chemotherapy

y composition was studied in 31 patients receiving chemotherapy for small-cell lung cancer. Patients were randomly assigned to receive either 4 weeks of total parenteral nutrition (study group) or to continue a self-regulated oral diet (control group). The relationship between height and total body nitrogen was altered initially for patients who had lost more than 5% of body weight. During the 4 weeks of parenteral nutrition, body weight, total body fat, and total body potassium, but not total body nitrogen, increased significantly in the study group (p less than 0.001). However, after parenteral nutrition was stopped, body weight and potassium levels in the study group fell significantly and to the same extent as in the control group. Nitrogen levels showed an overall fall in the 32 weeks of observation for both groups. After the period of parenteral nutrition, the decrease in body fat was significantly greater in the control group than in the study group (p less than 0.05). Thus, parenteral nutrition increased body fat and total body potassium, but not total body nitrogen.

Orthostatic hypotension with brainstem tumors

Three patients with brainstem tumors had orthostatic hypotension as the major presenting manifestation. Two patients had primary tumors that involved the dorsal medulla, pons, and rostral spinal cord; one was a malignant astrocytoma and the other a hemangioblastoma. The third patient had an oat cell carcinoma of the lung with subependymal spread to the medulla, pons, hypothalamus, and thalamus. Evaluation of baroreceptor function in the patient with the malignant astrocytoma showed a defect in the efferent sympathetic limb of the baroreceptor reflex arc.

Serum-dependent "cannibalism" and autodestruction in cultures of human small cell carcinoma of the lung

In cell lines of human small cell carcinoma of the lung (SCCL) and in all subclones of one of the cell lines, cells were observed which completely interiorized other cells, leading to death of the interiorized cells and sometimes to complete autodestruction of the cultures. This phenomenon, which we have called "cannibalism," is also observed in fresh tumor biopsies from SCCL patients. Cannibalistic cells appeared to be of SCCL origin. "Cannibalism" is never observed in serum-free cultures but can be reinduced by serum exposure. It is likely that "cannibalism" may contribute to the frequent failure to establish SCCL cell lines in serum-containing medium. The potential to induce autodestruction of tumor cells in SCCL patients by as yet unknown serum factor(s) may be of therapeutic value.

Small cell bronchogenic carcinoma: factors associated with pneumonia during chemotherapy

Sixty-five patients with small cell bronchogenic carcinoma were treated with intensive induction chemotherapy and supportive treatment. The clinical course of 43 patients who had pretreatment spirometry and arterial blood gases was studied. Thirteen patients developed pneumonia. Moderate hypoxemia, advanced age, and a low forced expiratory flow 25%-75% were associated with the development of pneumonia. Endobronchial obstruction and neutropenia, other factors associated with infection in cancer patients, appeared to be less important in this patient population.

Ventilation/perfusion relations in patients with small cell anaplastic carcinoma of the lung, obtaining complete remission during combination chemotherapy

81mKr ventilation lung scans, 99mTc perfusion lung scans and lung function tests were performed in 25 patients with small cell lung cancer during combination chemotherapy in order to characterize the physiological changes in responding patients. After 3 months of chemotherapy 12 patients had obtained complete remission (CR), with total disappearance of all visible tumor tissue at the chest X-ray, 5 had obtained partial remission, 2 had progressive disease and 6 had died. Prior to treatment a mixed pattern of restrictive and obstructive lung function decrease was observed. The patients had a significant decrease in both ventilation and perfusion (P less than 0.01) of the affected lung and a ventilation perfusion mismatch was seen. Three months after initiation of treatment the patients who obtained CR had a statistical improvement (P less than 0.01) of TLC, VC and FEV in 1 sec, rendering them statistically inseparable from a healthy control group. The ventilation of the affected lung in patients obtaining CR increased statistically (P less than 0.01), but only a minor increase in perfusion (P less than 0.1) was seen so that the ventilation-perfusion ratio remained distorted. It is concluded that even though an increase of static and dynamic lung function parameters, including the ventilation of the affected lung, are seen in patients with small cell lung cancer obtaining complete remission during combination chemotherapy, a marked functional decrease of the perfusion and a ventilation-perfusion mismatch remain.

[Lambert-Eaton syndrome and myasthenia. Nosologic discussion]

The Eaton-Lambert syndrome is a presynaptic neuromuscular blockade with well-defined electrical characteristics. It contrasts with the postsynaptic neuromuscular blockade which typifies myasthenia gravis. A review of the literature shows that cases do not always perfectly fit the description by Eaton and Lambert and that both kinds of blockade may be associated as in the observation reported here. Since its first description in 1956, there have been many publications on the Eaton-Lambert syndrome. However, there are cases in which both types of blockade; i.e. myasthenic and pseudo-myasthenic, are associated and the following case-report has seemed to us worthy of interest.

Regional lung function in patients with a complete radiographic regression of small cell bronchogenic carcinoma

Regional lung function was studied in 21 patients with small cell bronchogenic carcinoma who demonstrated a complete radiographic regression of intrathoracic tumour after 3 months of combination chemotherapy. Spirometry was performed in 20 patients. VC and FEV1 were, on average, 89 and 88% of predicted normal values. Impairment of ventilation and/or perfusion at the site of previous tumour was documented in 13 patients, while no such abnormalities were observed in 8 cases. Reduction of blood flow was generally more severe than impairment of ventilation. Neither median survival nor disease-free 2-yr survival was improved in patients with normal regional lung function compared to patients with functional impairment. This lack of survival advantage suggests that factors other than persistent tumour, such as scar formation, may contribute to reduction of regional lung function after chemotherapy for small cell bronchogenic carcinoma.

Cellular origin of the chemokinetic inhibitor of polymorphononuclear leucocytes found in sera from patients with chronic lymphocytic leukaemia

In a previous study, we demonstrated the existence in serum from patients with chronic lymphocytic leukaemia (CLL) of a cell-directed, heat-labile chemokinetic inhibitor of polymorphonuclear leucocytes (PMN). The aim of this investigation was to study the cellular origin of this inhibitor. Supernatants from short term cultured lymphocytes from 3 healthy persons and 5 patients with CLL, and from 16 different established human non-haematopoietic and haematopoietic cell lines were analyzed. Only the leukaemic B-lymphocytes from the CLL patients produced the inhibitor. The presence of the inhibitor was also demonstrated in supernatants from the fresh CLL cells from one CLL patient and a leukaemic cell line established from these cells using Epstein-Barr virus as the immortalizing agent. A lymphoblastoid cell line derived from the normal B-cells of the same CLL patient did not produce the chemokinetic inhibitor. We therefore conclude that the cellular origin of the heat-labile, cell-directed chemokinetic inhibitor of PMN migration is the CLL cell.

Effects of intensive chemotherapy on respiratory function in patients with small cell carcinoma of the lung

The lung function of 30 consecutive patients with small cell carcinoma of the lung was evaluated before and 3 months after initiation of intensive chemotherapy. Radiological evaluation of the therapeutic effect on the lung tumor was possible in 19 patients after 3 months. Six patients achieved complete normalization of the chest X-ray, 10 patients achieved more than 50% reduction of the tumor and no or minimal changes in the radiological image were observed in 3 patients. Before treatment a mixed pattern of obstructive and restrictive lung disease was observed in all patients. In the 16 patients who achieved partial or complete remission of the tumor normalization of the total lung capacity (P less than 0.02), vital capacity (P less than 0.02), FEV1 (P less than 0.02) and PEF (P less than 0.05) was observed independently of the degree of shrinkage of the tumor on chest roentgenogram, thus suggesting that the tumor was the major cause of the lung function impairment in these patients. The diffusion capacity and parameters reflecting the function of the small airways (RV/TLC% and MEF50) remained abnormal after treatment. Improvement of the lung function did not predict the individual duration of survival. However, the study proved that roentgenological normalization is paralleled by physiological normalization with the current treatment of this disease.

Effects of dibutyryl cyclic adenosine 3':5'-monophosphate on the growth of cultured human small-cell lung carcinoma and the specific cellular activity of L-dopa decarboxylase

High activity of L-dopa decarboxylase separates small (oat)-cell from non-small-cell lung cancer in cell culture. The present study investigates relationships between the specific cellular activity of this enzyme and: (a) cell growth kinetics of an established line (O-H-1) of human small cell lung carcinoma, and (b) responses of these cells to treatment with cyclic adenosine 3':5'-monophosphate and sodium butyrate. The O-H-1 cells, as for most other established small-cell lines, grow as suspended cell aggregates. During growth, the specific cellular activity of L-dopa decarboxylase parallels levels for [3H]thymidine labeling index and the ratio of cells in G2-M to those in G1-G0 phases of the cell cycle. Each of these parameters is 2- to 3-fold higher during exponential versus stationary growth. Continuous treatment with dibutyryl cyclic adenosine 3':5'-monophosphate (dcAMP; 0.1 or 1 mM) and 1 mM theophylline produces simultaneous cessation of cell growth and an increase in cellular L-dopa decarboxylase activity. During this period, analyses of DNA histograms reveal an increase in the number of cells in the G2-M phase; the rate of increase in the ratio of G2-M to G1-Go cells paralleled the rate of increase in specific activity of the enzyme. The effects of the dcAMP were promptly reversible; release of the apparent G2-M block preceded regrowth of the cells and was accompanied by a return of L-dopa decarboxylase activity to base-line levels. The changes in enzyme activity were specific for cyclic adenosine 3':5'-monophosphate; another cyclic adenosine 3':5'-monophosphate analogue, 8-bromo adenosine cyclic 3':5'-monophosphate yielded similar increases in L-dopa decarboxylase to those seen with dcAMP, while 0.01 to 1 mM butyrate alone produced the inhibition of cell growth but no changes in specific activity of L-dopa decarboxylase or percentage of cells in the different phases of the cell cycle. We conclude that the specific activity of L-dopa decarboxylase, a key neuroendocrine marker for cultured small-cell lung carcinoma, is highest during proliferative growth and/or when these cells are in the G2M phase of the cell cycle. The differential effects of dcAMP and sodium butyrate offer potential for exploring neuroendocrine differentiation in this important lung cancer and related endocrine neoplasms.

Induction of cytoskeleton-associated proteins during differentiation of human myeloid leukemic cell lines

Alterations in the expression of proteins associated with the cytoskeletal framework during differentiation of two human myeloid leukemia cell lines were analyzed by two-dimensional gel electrophoresis of Triton-insoluble cellular framework fractions. During in vitro differentiation of HL60 (human promyelocytic leukemia line) and U937 (human monocytoid leukemia line), several new cytoskeleton-associated (CSK) proteins are induced. All of these CSK proteins are also present in freshly isolated normal granulocytes and macrophages. One of these differentiation-induced proteins comigrates with vimentin. There are several differentiation-sensitive proteins, i.e., those that are no longer synthesized upon differentiation. The changes in CSK protein synthesis during differentiation of HL60 and U937 cells do not seem to be related to drug treatment per se since exposure to conditioned medium from phytohemagglutinin-stimulated lymphocytes as well as to dimethyl sulfoxide and 12-O-tetradecanoylphorbol-13-acetate results in the production of many similar proteins. In vitro conditions that do not result in differentiation of HL60 and U937, such as cultivation in serum-free medium, do not induce the CSK proteins that we describe. A notable finding in this study is that all of the qualitative changes in the proteins synthesized during differentiation are detected in the cytoskeletal (Triton-insoluble) fraction, whereas only minor quantitative alterations are observed in the Triton-insoluble extract. The changes in CSK protein components occur in an orderly fashion. Vimentin, an intermediate-filament protein, is synthesized in large amounts prior to changes in cellular morphology and the induction or loss of other CSK proteins. Vimentin may play an important role in the reorganization of the cytoskeleton to support the process of differentiation. The other CSK proteins are synthesized sequentially along with the morphological and functional changes during differentiation. These model systems, therefore, present an opportunity to investigate the role of specific cytoskeletal components in cellular differentiation.

Measurement of surface temperature in lung cancer

We measured the surface temperature of the tumors in 27 patients with primary lung cancer, using a flexible bronchofiberscope and a thermometer made from chromel-constantan. The thermometer was inserted into the aspiration channel of the bronchofiberscope, and temperature was studied under bronchofiberscopic located in the central portion of the lung were higher than those of the carina of the trachea (P less than 0.01), truncus superior (P less than 0.01), or truncus inferior (P less than 0.05), and almost equal to those of the peripheral lung. Thus, lung cancer showed a significantly higher surface temperature. When 67Ga scintigraphy was performed in 22 patients with lung cancer, the temperature of the high-uptake group was higher than that of the low-uptake group.

Evaluation of blood-brain barrier permeability changes in rhesus monkeys and man using 82Rb and positron emission tomography

Dynamic positron tomography of the brain with 82 Rb, obtained from a portable generator [82Sr (25 days) - 82 Rb (76 sec)], provides a means of studying blood-brain barrier (BBB) permeability in physiological and clinical investigations. The BBB in rhesus monkeys was opened unilaterally be intracarotid infusion of 3 M urea. This osmotic barrier opening allowed entry into the brain of intravenously administered rubidium chloride. The BBB opening was demonstrated noninvasively using 82Rb and positron emission tomography and corroborated by the accumulation of 86Rb in tissue samples. Positron emission tomography studies can be repeated every 5 min and indicate that dynamic tomography or static imaging can be used to study BBB permeability changes induced by a wide variety of noxious stimuli. Brain tumors in human subjects are readily detected because of the usual BBB permeability disruption in and around the tumors.

Posttetanic potentiation in a patient with myasthenia gravis

We studied a patient with clinically typical myasthenia gravis (MG) and high serum titer of antibodies to acetylcholine receptor. Unlike the usual response in MG, there was an increment in the amplitude of the electrical response (308% of control) after 10 seconds of voluntary tetanus. Posttetanic facilitation is usually less than 200% in MG and over 200% in Eaton-Lambert syndrome. However, there have been several other cases of typical MG with increments over 200%. Facilitation of this magnitude has also been seen with curare administration in animals and man. However, in myasthenia, as opposed to curare poisoning, competitive blocking is not thought to exist.

Calcium spike electrogenesis and other electrical activity in continuously cultured small cell carcinoma of the lung

Spike electrogenesis, local depolarizing and hyperpolarizing responses, spontaneous rhythmic firing, and alternating resting potentials were measured in cells from a continuously cultured small cell carcinoma of the lung. Spike generation was blocked by MnCl2. In view of this evidence for calcium-spike electrogenesis and previous evidence of secretory activity in these cells, this cell line (DMS 53) can provide a model for the study of excitation-secretion behavior in human neoplastic cells.

Selective growth in serum-free hormone-supplemented medium of tumor cells obtained by biopsy from patients with small cell carcinoma of the lung

Fifteen tumor-containing specimens were obtained directly from patients with small cell carcinoma of the lung and tested for their ability to grow in serum-supplemented medium and in serum-free medium supplemented with hydrocortisone, insulin, transferrin, estrogen, and selenium (HITES). The tumor cells replicated in 14 of 15 cases (93%) in the HITES medium and in 10 of 15 cases (67%) in the serum-supplemented medium. The neoplastic origin of the cells growing in the HITES medium was confirmed by standard cytologic criteria, by DNA content analysis using flow cytometry, and by their ability to form colonies in agarose and tumors in athymic nude mice. While the tumor cells had very similar morphologies in both media, the serum-free medium did not support the growth of nonmalignant stromal cells, and essentially pure cultures of replicating tumor cells were obtained 7-10 days after plating. The selectivity of the HITES medium was demonstrated by the failure of cells to grow in 20 specimens cytologically negative for small cell carcinoma and in 9 of 10 specimens containing other tumor types (including other types of lung cancer). The results demonstrate that a chemically defined medium, determined by work on tissue culture-adapted human tumor lines, can support the selective growth of tumor specimens obtained directly from patients. Such selective formulas are probably specific for different tumor types and thus could be used for diagnosis, drug sensitivity testing in vitro, and identification of factors regulating tumor growth. All of these have direct application to patient treatment.

Adrenocortical function compared with computed tomography of the adrenals in small cell carcinoma of the lung

Autopsy in patients with pulmonary small cell carcinoma frequently reveals metastases to the adrenal glands. In order to test the hypothesis that CT scanning might demonstrate such metastases at the time of clinical diagnosis of the pulmonary disease, the results of adrenal CT in 15 patients were correlated to adrenocortical function tests. No statistically significant relationship was found. It is concluded that no reliable non-invasive method exists to diagnose adrenal metastases in patients with pulmonary small cell carcinoma.

Phagocytic tumor cell activity in oat cell carcinoma of the lung

Biopsy specimens from 14 patients with oat cell carcinoma of the lung metastatic to bone marrow and from one patient with a localized tumor were examined for evidence of phagocytic activity by tumor cells. Phagocytic activity was observed in tumor cells in 90 per cent of the bone marrow biopsy specimens, 90 per cent of the cytology specimens, and 70 per cent of the biopsy specimens of other tissues. The cell most often phagocytosed was the leukocyte. Seventeen other tumors metastatic to bone marrow were studied and only one evidenced phagocytic activity.

Ectopic hormone production by tumours. Clinical aspects

The ectopic production of hormones by tumours is important to appreciate as relevant endocrine features may antedate the appearance of other evidence of the tumour. This possibility should be borne in mind particularly when considering Cushing's syndrome, excessive ADH production or hypercalcaemia and could result in many instances in a quite different approach to further investigation and management. Carcinoma of lung is the commonest underlying neoplasm in several such situations but there are some, such as the hypoglycaemic syndromes, in which the tumour may even be benign.