In vivo targets of recombinant human tumour necrosis factor-alpha: blood flow, oxygen consumption and growth of isotransplanted rat tumours

The impact of recombinant human tumour necrosis factor-alpha (1 microgram kg-1 to 1 mg kg-1; 6.6 x 10(6) U mg protein-1) on blood flow, oxygen consumption and growth of a moderately TNF-sensitive rat tumour (DS-carcinosarcoma) was studied. Tumour growth was stimulated at low TNF doses (1 and 10 micrograms kg-1) and significantly retarded at higher TNF dose levels (0.1 and 1 mg kg-1). Growth changes were concomitant with variations in oxygen consumption, lactate release and acidification of the metabolic micromilieu. Both single and repeated application of low TNF doses (1-10 micrograms kg-1 i.v.) increased tumour perfusion whereas single administration of high TNF dose levels (0.1-1 mg kg-1 i.v.) reduced tumour blood flow. After repeated application of high TNF doses tumours shrank to such small sizes that perfusion measurements could not be performed within the observation period of two weeks. It is concluded that TNF effects on solid tumours are at least partially mediated by changes in tumour perfusion. Thus, an altered tumour sensitivity towards other treatment modalities, e.g. irradiation, chemotherapy or hyperthermia, can be expected after TNF therapy. A beneficial TNF effect would critically depend on the dose level employed and on the sequence and timing of various combination regimes.

True carcinosarcoma of the maxillary sinus

A case of true carcinosarcoma primarily arising in the right maxillary sinus is reported in a 60-year-old male. His chief complaints were right nasal obstruction and bleeding. Histological findings of the biopsied primary tumor revealed two components of keratinizing squamous cell carcinoma and osteosarcoma which were intricately intermingled. Despite intensive irradiation and chemotherapy, and total maxillectomy, he finally died of rapid tumor recurrence and widely spreading metastases to lungs, pleurae and brain two months later. At autopsy the recurrent and metastatic tumors consisted entirely of the osteosarcoma component, suggesting the efficiency of the radiotherapy and chemotherapy against the carcinomatous component, but not against the sarcomatous one. As for histogenesis, this case was compatible with a combination tumor judging from histologic, immunohistochemical and electron microscopic findings.

Comparative effects of tumour necrosis factor-alpha (cachectin), interleukin-1-beta and tumour growth on amino acid metabolism in the rat in vivo. Absorption and tissue uptake of alpha-amino[1-14C]isobutyrate

The effects of acute administration of either tumour necrosis factor-alpha (cachectin) (TNF) or interleukin-1-beta (IL-1), or of tumour growth (Walker-256 carcinosarcoma), on blood amino acid concentrations and tissue alpha-amino[1-14C]isobutyrate (AIB) uptake in virgin and lactating rats were compared. Both monokines decreased the blood concentrations of those amino acids (serine, glycine, alanine and proline) transported via the A system. Tumour growth decreased the blood concentrations of serine, proline and histidine, whereas the concentrations of glutamine and leucine were increased. IL-1 decreased the intestinal absorption of AIB in all groups studied; TNF or tumour growth had no effect. Tissue AIB uptake was increased (1.5-2.5-fold) in liver, whereas it was decreased in heart and skeletal muscle of the three treatment groups (except skeletal muscle of the IL-1-treated rats). Lactating rats had lower hepatic uptake of AIB compared with livers of virgin rats. IL-1 increased the hepatic uptake of AIB in lactating rats, but not to the values seen in virgin rats treated with IL-1; there was no effect of the cytokine on muscle or mammary-gland uptake. In adrenalectomized rats, the stimulatory effect of IL-1 on hepatic AIB uptake was diminished, whereas that of TNF still persisted. IL-1 caused a marked decrease of AIB uptake in muscle and heart of adrenalectomized rats, which was accompanied by an increase in the blood concentrations of branched-chain amino acids. These effects did not occur with TNF. It is concluded that the effects of the cytokines on tissue amino acid metabolism may depend on a differential endocrine response involving glucagon and/or glucocorticoids.

Characterization and estrogen regulation of growth factor activity from uterus

Acid-stable uterine-derived growth factor activity, extracted from uteri of several species (rat, rabbit and bovine), stimulates DNA synthesis as measured by [3H]thymidine incorporation into hamster uterine carcinosarcoma (UCS) cells. A time course of [3H]thymidine incorporation demonstrates maximum incorporation at 24 h. These extracts also stimulate [3H]thymidine incorporation in a variety of other cell types from 17 beta-estradiol (E2) target tissues and non-target tissues. Uterine extracts from E2-treated ovariectomized rats show a 3-fold increase in growth factor activity above control values. Activity is elevated within 18-24 h after estradiol injection and remains elevated wtih subsequent injections. Growth factor activity is acid-stable, heat-labile, reduced by trypsin but not reduced by treatment with dextran-coated charcoal. Gel filtration shows molecular weight (Mr) heterogeneity with activity eluting at Mr of 10,000-30,000. Since uterine extracts can restore in vitro the estrogen-regulated properties of uterine growth observed previously in vivo, it is possible that the substances found in these extracts may be mediators of E2 actions.

Carcinosarcoma of the urinary bladder. A light, immunohistochemical and electron microscopical case report

A case of urinary bladder carcinosarcoma (UBCS) is reported with light, immunohistochemical and electron microscopical findings. The tumour consisted of a squamous cell carcinoma, variable spindle cell stromal elements compatible with fibrosarcoma, and rhabdomyoblasts. Intermediate filament co-expression of cytokeratin and vimentin was shown by immunohistochemistry. Electron microscopy (EM) confirmed the nature of the three components, and indicated some similarities between the three cell-types present. Comparisons with the previous UBCS in the literature are made.

Growth-related changes of oxygen consumption rates of tumor cells grown in vitro and in vivo

Growth-related changes of oxygen consumption rates of tumor cells, grown in vitro or in vivo, were investigated. For in vitro investigations, L929 and DS-carcinosarcoma cells were cultured in artificial media. For in vivo studies, DS-carcinosarcoma cells were implanted into the abdominal cavity of Sprague-Dawley rats (ascites tumor, containing malignant cells, leukocytes, lymphocytes, and macrophages). Oxygen uptake was measured photometrically. Parameters of the extracellular medium judged to possibly influence the respiratory activity of tumor cells were monitored at different growth stages (glucose, lactate, and amino acid levels, oxygen and carbon dioxide partial pressures, and pH values). The results obtained clearly show that the oxygen uptake of tumor cells grown in vitro decreased as quiescence developed. In contrast, the respiratory activity of in vivo DS-carcinosarcoma ascites cells increased as tumor growth reached plateau phase. The differences observed cannot be attributed solely to changes of the environmental conditions monitored. It is likely that an increased respiration rate of activated host cells might profoundly contribute to the elevation of the respiratory capacity of DS-carcinosarcoma ascites tumors grown in vivo. These data provide evidence that solid tumors in vivo can increase their O2 uptake at an enhanced O2 availability not only due to an enlarged tumor volume with adequate O2 supply but also due to an elevation of the respiratory activity of different cell populations within a tumor.

Carcinosarcoma of the uterine cervix initially interpreted as high grade sarcoma

Carcinosarcoma of the uterine cervix is a rare tumor. A case of carcinosarcoma of uterine cervix initially interpreted as sarcoma, NOS, is presented along with immunohistochemical findings.

[Immunohistological demonstration of the intermediate filaments in a laryngeal carcinosarcoma: considerations on its histogenesis]

A carcinosarcoma of the larynx was analysed by means of a light microscope and by immunohistological staining technique using antibodies against various intermediate filament proteins. Whereas tumour areas of an epithelial character reacted with antibodies against keratin, the spindle cells demonstrated a positive immunofluorescence with vimentin antibodies. Inside some tumour cells a coexpression of keratin and vimentin (intermediate filaments of mesenchymal cells) could be demonstrated. It is likely that these double stained cells represent the primitive stem cell of the carcinosarcoma, differentiating during further development either into epithelial or mesenchymal tumour cells.

L-glutamine: a major substrate for tumor cells in vivo?

From 65 human breast cancer xenografts investigated, a net glutamine uptake was found in 13 tumors (mean +/- SE: 15.7 +/- 4.5 nmol/g per min) whereas a net release (22.5 +/- 3.3 nmol/g per min) was observed in 40 tumors. In 12 tumors neither a significant net uptake nor a net release was obvious. There is experimental evidence that glutamine is taken up by cancer cells only at arterial concentrations greater than 0.5 mM. Another parameter determining glutamine utilization by tumor cells may be the tissue oxygenation. In hypoxic or anoxic tumor areas, glutamine oxidation is unlikely since oxygen is required for the reoxidation of coenzymes which are reduced in the course of this metabolic pathway. The pronounced net release could be due to proteolysis within the tumors investigated. In ascitic fluid (DS-carcinosarcoma), glutamine accumulated during growth, implicating a reduction in the glutamine consumption rate, proposedly also due to a worsening of the oxygen supply to the suspended tumor cells. Thus, the generally held opinion that L-glutamine is a (if not the) major substrate for the energy metabolism of rapidly growing tumor cells should be reconsidered since evidence for this hypothesis has been derived mainly from in vitro systems with abundant oxygen.

Distribution studies of 111In-oxine-labeled peritoneal mononuclear cells in tumor-bearing rats

We studied the distribution of 111In-labeled peritoneal mononuclear cells (PMC) in Sprague-Dawley rats with carcinosarcoma (CS) tumor. We obtained PMC from normal rats and rats pretreated with BCG or irradiated CS cells as antigenic stimulant. PMC were labeled in-vitro with 111In-oxine and transferred by tail-vein injection to rats bearing CS tumor. Twenty-four, 48 and 72 h after PMC transfer, we measured the accumulation of these cells in the CS tumor as a percentage of dose radioactivity per gram of tumor using an external gamma-ray camera. PMC from normal and BCG treated donor rats accumulated 0.4% and 0.46% dose per gram of CS tumor respectively. PMC from donor rats given killed CS cells accumulated significantly greater concentrations of 111In (0.79% dose per gram of CS tumor, P less than 0.025). Thus killed CS cells were able to sensitize the PMC of normal rats. 111In-oxine-labeling is an elegant procedure to study the distribution of mononuclear cells in tumors.

Carcinosarcoma of bladder. Evaluation by electron microscopy and immunohistochemistry

A case of carcinosarcoma of the urinary bladder characterized by electron microscopy and immunohistochemistry is described. The use of these studies in poorly differentiated bladder neoplasms and in suspected cases of carcinosarcoma is encouraged. Increased accuracy in characterizing these tumors will permit a better understanding of their natural history and response to therapy.

Hemodilution in isolated tumor perfusion

Experiments are performed to study the influence of local hemodilution on tumor blood flow, oxygen availability in tumor tissue and O2 consumption of cancer cells. The results obtained clearly show that hemodilution in isolated tumor perfusion can distinctly improve nutritive blood flow through solid tumors. This can be utilized to enhance pharmacokinetics of antitumor drugs. Due to the improved metabolic status, the pharmacodynamics of some antitumor drugs should also be enhanced. To achieve a maximum improvement of the O2 supply to the tumor, hematocrit values should not be decreased below 0.20.

Impact of various thermal doses on the oxygenation and blood flow in malignant tumors upon localized hyperthermia

Upon localized hyperthermia at modest thermal doses an increase in tumor blood flow can be observed in many tumors which is paralleled by an improvement of the oxygenation status of the tissue. At intermediate or high thermal doses a pronounced restriction of the tumor circulation becomes obvious leading to a deterioration of the tumor oxygenation. As a consequence, a further enhancement of the thermal response of tumors relative to normal tissues has to be expected at intermediate or high thermal doses.

Factors associated with humoral hypercalcemia of malignancy stimulate adenylate cyclase in osteoblastic cells

The culture media of three cell lines, a human prostate carcinoma (PC3), a rat Leydig cell tumor (Rice-500), and a rat carcinosarcoma (WRC-256), that were derived from tumors associated with humoral hypercalcemia of malignancy (HHM), were examined for stimulation of adenylate cyclase in ROS 17/2.8 osteoblastic cells and for bone resorptive activity in culture. Cells from a nonhypercalcemic variant of the WRC256 tumor served as control. Extracts from three solid human tumors, a lung adenocarcinoma from a patient with HHM and two adenocarcinoma from normocalcemic patients (lung and colon), were also examined for adenylate cyclase stimulation. We found excellent correlation between stimulation of cyclic AMP accumulation in ROS 17/2.8 cells and bone resorbing activity in culture, or production of HHM in vivo. Stimulation of adenylate cyclase by HHM factors was inhibited by the parathyroid hormone competitive inhibitor, [8norleucyl, 18norleucyl, 34tyrosinyl] bovine parathyroid hormone (3-34) amide.

Tumour oxygenation under normobaric and hyperbaric conditions

Tumour oxygenation during exposure to normobaric and hyperbaric oxygen was assessed by means of a cryophotometric micromethod and a specially constructed pressure chamber. The tumours investigated were DS-carcinosarcomas implanted subcutaneously into the thigh of Sprague-Dawley rats. The animals were anaesthetised and put on a heating pad. Mean arterial blood pressure was monitored throughout the entire time of pressurisation. Cryobiopsies were removed from the tumours after exposure to O2 for 30 min at 1 bar (atmospheric pressure), 2, 3, or 4 bar. Oxyhaemoglobin saturation (HbO2) values of single red blood cells in tumour microvessels were determined photometrically in the frozen tissue samples as a quantitative measure for tumour oxygenation. Frequency distribution curves of HbO2 showed that there was a marked improvement of the O2 supply to tumour tissue in O2 atmospheres at 1 bar compared with exposure to air at 1 bar. Pressurisation in O2 atmospheres up to 2 and 3 bar did not substantially alter the distribution curve of the HbO2 values in comparison with the data sampled at 1 bar O2 exposure, yet led to a significant drop in the occurrence of HbO2 values below 5% saturation. Thus, pressurisation particularly raises those tissue O2 partial pressures (pO2) that are in a range where the radiosensitivity is critically influenced by the pO2. Pressurisation up to 4 bar caused a shift of the HbO2 distribution curve to values significantly higher than those from tumours exposed to O2 at 1 bar, with no values below 35% saturation. Using these data and a previously published model for computing tissue pO2 values it can be shown that radiobiological hypoxia is unlikely to occur in DS-carcinosarcomas exposed to an O2 atmosphere at 4 bar under the conditions chosen. Hyperbaric oxygenation is recommended as an efficient adjuvant of X irradiation, particularly in superficial tumours.

Non-bicarbonate buffering of ascites tumor cells in the rat as titrated by strong acids

Buffer equations originally derived for blood were applied to the in vitro system "ascites tumor cells and ascitic fluid'. Non-bicarbonate buffer values beta(mmol x pH(-1) x 1(-1)) were determined experimentally by titration of ascites, cell free ascitic fluid and cell homogenates with NaOH in the absence of CO2. beta in ascitic fluid, in native ascites and in cell homogenate were beta (F) = 5.9, beta (A) = 16.4 and beta (H) = 24.9, respectively. Intracellular beta value beta (C) calculated from buffer equations depended on the ratio delta pHi/delta pHe. With delta pHi/delta pHe = 1, beta (C) was 38.8. The difference between beta (C) and beta (H) could be partly accounted for by differences in the cellular protein content. With delta pHi/delta pHe = 0.62 as in the presence of CO2, beta (C) becomes 62.6. In the presence of CO2 (see Albers et al., 1981), the extracellular buffering was higher and the intracellular buffering lower than the values titrated in the absence of CO2. It is concluded that in the presence of CO2 and/or HCO3- the apparent intracellular buffering of intact tumor cells results from non-bicarbonate buffering by cell proteins as well as from active or passive ionic exchanges with the extracellular fluid.

Effect of CO2 and lactic acid on intracellular pH of ascites tumor cells

The effect of CO2 and of lactic acid (L.A.) on the extracellular (pHe) and intracellular pH (pHi) of ascites tumor cells (DS-carcinosarcoma) in rats was studied by in vitro equilibration of ascites with CO2 and alteration of lactic acid concentration. pHi was determined by the distribution of DMO. The effects of lactic acid and CO2 on pH were additive and could be expressed as pHe = 8.872 - 0.745 logPCO2 - 0.0355 (L.A.) (R = 0.867, n = 201) pHi = 8.218 - 0.436 logPCO2 - 0.0275 (L.A.) (R = 0.812, n = 143) delta pHi/delta pHe was dependent on the way pHe was changed: If the change in pHe was due to lactic acid, delta pHi/delta pHe was 0.91; if it was due to CO2 delta pHi/delta pHe was 0.625. pHi exceeded pHe if either PCO2 and/or the concentration of lactic acid was raised above a critical level. The results render it questionable to predict intracellular pH values within solid tumor from pH measurements within the extracellular fluid.

Circulatory and metabolic responses of malignant tumors during localized hyperthermia

The effect of localized hyperthermia on the circulatory responses and on the oxygen and glucose supply has been evaluated in tissue-isolated rat tumors utilizing an in situ perfusion system. On the average, localized hyperthermia caused a significant increase in total tumor blood flow after raising of the mean tumor temperature from 37 degrees C to 39.5 degrees C. At higher temperatures (42 degrees C) total tumor blood flow decreased to a level somewhat below the flow during normothermia. However, there were great interindividual differences in the response of blood flow to temperature. The changes in blood flow were paralleled by variations of the O2-consumption and of the glucose uptake of the tumor tissue. The alteration of the oxygen and glucose supply seem to be predominantly mediated through changes of tumor blood flow with temperature. Tumor microcirculation appears to be improved at moderate hyperthermic temperatures (39 degrees C -40 degrees C) and deteriorated at higher temperatures. Whereas a vasodilation of tumor vessels seems to be a paramount factor for flow improvements, a reduction of red blood cell flexibility due to severe tissue acidosis, multiple microthromboses as well as occlusions of microvessels should be taken into consideration as factors for flow impairments at higher tumor temperatures.

Oxygen diffusivity in tumor tissue (DS-carcinosarcoma) under temperature conditions within the range of 20--40 degrees C

The O2 diffusion constants D and K of tumor tissue (DS-Carcinosarcoma in the rat kidney) were determined at temperatures of 20, 30, 37, and 40 degrees C. The following mean values were obtained for the conditions of 37 degrees C: D = 1.75-10(-5) cm2/s and K = 1.9-10(-5) mlO2/cm-min-atm. Within the range of 20-40 degrees C, temperature variations in tumor tissue cause changes in the O2 diffusion coefficient D of 2.0-2.5%/C and in the Krogh O2 diffusion constant K of 0.5-1.5%/C. The measured O2 diffusion constants for tumor tissue correspond to values of normal tissue with similar water content. This indicates that the insufficient O2 supply in DS-Carcinosarcoma is due not to unfavorable O2 diffusivity of the tumor tissue but rather to a decreased convective O2 transport and to insufficient capillarization. An analysis of O2 diffusion in DS-Carcinosarcoma tissue using the determined O2 diffusion constants lead to the result that, under the conditions of arterial normoxia and normocapnia, critical O2 supply conditions are to be expected when the intercapillary distance exceeds approximately 120 micrometer.

Two syngeneic cell lines from human breast tissue: the aneuploid mammary epithelial (Hs578T) and the diploid myoepithelial (Hs578Bst) cell lines

We characterized two human cell lines (Hs578T and Hs578Bst), which provide several unique features that should be useful in the study of breast disease. Hs578T, derived from a carcinosarcoma, is epithelial in origin. Hs578Bst, established from normal tissue peripheral to the tumor, is myoepithelial in origin. This is the first report of companion cell lines, one malignant and one normal, established from the same organ.