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F Kallinowski

Publications and source records attributed to F Kallinowski.

At least 55 records · Page 3Linked to original sources

Blood flow, oxygen consumption and tissue oxygenation of human tumors.

The objective of this article was to summarize current knowledge of blood flow and oxygen supply to human tumors, parameters which go hand in hand, and in turn critically determine the cellular metabolic microenvironment of human malignancies. A compilation of available data on blood flow, oxygen supply, and tissue oxygen distribution in human tumors is presented. Though data on human tumors in situ are scarce and there may be significant errors associated with the techniques used for measurements, experimental evidence is provided for the existence of a compromised and anisotropic blood supply to many tumors. Comparable to rodent tumors, O2-depleted areas develop in human malignancies which coincide with nutrient and energy deprivation, and with a hostile metabolic microenvironment. Significant variations in these relevant parameters have to be expected between different locations within the same tumor, at the same location at different times, and between individual tumors of the same grading and staging.

Erythrocytes↗

Oxygenation of tumors derived from ras transformed cells.

In order to gain insight into mechanisms governing the development of tumor hypoxia, malignancies derived from spontaneously tumorigenic or ras-transformed cell lines were grown in nude mice. As a rule, tumors with ras oncogenes exhibited rapid growth rates and large areas with low pO2 readings even at small tumor sizes. The slow proliferation rate of a spontaneously tumorigenic cell line was consistent with more adequate tissue oxygen levels. In all lines, hypoxia was accentuated at larger tumor sizes. These results demonstrate that ras transformation can lead to accelerated proliferation rates and is then concomitant with the development of pronounced tumor hypoxia.

Animals↗

Tumor tissue oxygenation as evaluated by computerized-pO2-histography.

A computerized pO2 measurement system with a novel electrode motion pattern (Sigma-pO2-histography) was evaluated in vitro and in vivo. The system was found to be reliable in 0.9% saline and 10% hydroxyethylene starch solution and in fresh donor blood. Marked deviations were found in lipid and hemoglobin solutions and in fluorocarbon emulsions. Histograms obtained in rat liver, mouse muscle, and subcutis were similar to previously reported distributions. Direct comparison between Sigma-Eppendorf and self-constructed Whalen-type electrodes in hypoxic tumors gave similar results. A large series of measurements indicated that hypoxic and anoxic tissue areas were frequently found both in isografted rodent and in xenografted human tumors. The extent of oxygen deprivation depended on the cell line studied, tumor size, implantation site, the vascularity, and the actual tissue perfusion. Pentobarbital anesthesia redistributed the tumor oxygenation without affecting the median pO2 value. Tumors growing in a pre-irradiated bed were less oxygenated than those at untreated sites. Hyperthermia at therapeutically relevant temperatures reduced pO2 levels in adequately oxygenated tumors whereas little change was detected in poorly oxygenated tumors. First measurements in tumors in patients revealed marked inter- and intratumor heterogeneity. It is concluded that this novel technique is suitable for routine measurements of tissue oxygenation of solid tumors in situ.

Animals↗

TNF alpha primes polymorphonuclear leukocytes for an enhanced respiratory burst to a similar extent as bacterial lipopolysaccharide.

We examined whether preincubating polymorphonuclear leukocytes (PMN) with TNF alpha would result in an enhanced respiratory burst upon subsequent stimulation by various agents. Bacterial lipopolysaccharide (LPS), a known primer of PMN, was used as control. We found that both LPS (0.01 to 10.0 microgram/ml) and recombinant TNF alpha (0.001 to 1.0 microgram/ml) act as direct stimulants of PMN as measured by chemiluminescence. Sixty minutes of preincubation of PMN with 1 microgram/ml TNF alpha or 10 micrograms/ml LPS resulted in similar priming for the respiratory burst elicited by opsonized zymosan, phorbol myristate acetate, zymosan, zymosan-activated serum, aggregated immunoglobulin, and f-met-leu-phe (FMLP) depending on the method of measurement used, i.e., chemiluminescence, production of O2-, and H2O2. Priming with TNF alpha for an enhanced response to stimulation by FMLP could be abrogated by anti-TNF alpha antibody. Cell-surface receptor numbers and binding-affinity constants for FMLP remained stable under conditions leading to priming. We conclude that TNF alpha is able to prime PMN for an enhanced respiratory burst to a similar extent as with LPS. Because PMN cell-surface receptors for FMLP are unaltered by priming, the enhanced respiratory burst seems to be due to changes in intracellular metabolism.

Antibodies↗

Blood flow, oxygen and nutrient supply, and metabolic microenvironment of human tumors: a review.

The objective of this review article is to summarize current knowledge of blood flow and perfusion-related parameters, which usually go hand in hand and in turn define the cellular metabolic microenvironment of human malignancies. A compilation of available data from the literature on blood flow, oxygen and nutrient supply, and tissue oxygen and pH distribution in human tumors is presented. Whenever possible, data obtained for human tumors are compared with the respective parameters in normal tissues, isotransplanted or spontaneous rodent tumors, and xenografted human tumors. Although data on human tumors in situ are scarce and there may be significant errors associated with the techniques used for measurements, experimental evidence is provided for the existence of a compromised and anisotropic blood supply to many tumors. As a result, O2-depleted areas develop in human malignancies which coincide with nutrient and energy deprivation and with a hostile metabolic microenvironment (e.g., existence of severe tissue acidosis). Significant variations in these relevant parameters must be expected between different locations within the same tumor, at the same location at different times, and between individual tumors of the same grading and staging. Furthermore, this synopsis will attempt to identify relevant pathophysiological parameters and other related areas future research of which might be most beneficial for designing individually tailored treatment protocols with the goal of predicting the acute and/or long-term response of tumors to therapy.

Adenosine Triphosphate↗

Tumor blood flow: the principal modulator of oxidative and glycolytic metabolism, and of the metabolic micromilieu of human tumor xenografts in vivo.

We have investigated therapeutically relevant pathophysiological parameters of human breast and lung cancer xenografts in nude rats. All lung cancers and one breast cancer exhibited rapid growth and high blood flow values paralleled by high metabolic rates. The tissue of these tumors was well oxygenated up to very advanced growth stages. Xenografts from other breast cancer cell lines grew much more slowly, were poorly perfused, and exhibited low metabolic rates. Here, tumor hypoxia and tissue acidosis were evident. These results indicate that significant differences in the metabolic micromilieu can be detected in human tumors; these are due to varying perfusion rates and may be partly responsible for failure to obtain tumor control in individual patients.

Animals↗

Blood flow, metabolism, cellular microenvironment, and growth rate of human tumor xenografts.

Better understanding of the micromilieu of human tumors in situ is mandatory for further improvement of diagnostic and therapeutic interventions. Since investigations of untreated tumors of a wide size range are precluded in humans for ethical reasons, size-dependent changes in the pathophysiology of primary and metastatic human tumors were studied using "tissue-isolated" xenografts in nude rats. Tumor types included lung and breast cancers, ovarian and thyroid carcinomas, uterus tumors, and melanomas. A 10-fold variation in weight-adjusted tumor perfusion indicated large variations in angiogenesis which were unrelated to tumor type. Flow values obtained were consistent with data from clinical observations and were comparable to that in isografted rodent tumors. Using actual consumption and supply rates, maximum oxygen and glucose uptake rates were calculated for each tumor type. The capacity to consume oxygen and glucose varied 9-fold and 4-fold, respectively. However, considering actual consumption rates, blood flow was the principal modulator of substrate supply and tumor metabolism in these human tumor xenografts. Consequently, therapeutically relevant parameters of the metabolic micromilieu largely depended on the efficacy of the tumor circulation. Hereby, high metabolic rates concomitant with high flow values coincided with rapid tumor growth. Thus, in order to design the best individualized therapy, flow-related data should supplement histological classification and clinical staging and grading. Further development of relatively noninvasive technologies (magnetic resonance imaging, magnetic resonance spectroscopy, or positron emission tomography) might permit such monitoring.

Animals↗

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.

Amino Acids↗

Effects of hydralazine on in vivo tumor energy metabolism, hematopoietic radiation sensitivity, and cardiovascular parameters.

Energy metabolism of murine FSaII foot tumors was studied by in vivo 31P-MRS in C3Hf/Sed mice. Spectroscopy was performed following exposure to escalating doses of hydralazine (HYD) ip. At 0.25 mg/kg, HYD caused a 20% increase in PCr/Pi and had no significant effect on mean arterial blood pressure. HYD doses greater than or equal to 2 mg/kg lead to hypotension which was associated with a decrease in PCr, NTP, pH, and an increase in Pi (p less than 0.01 for control vs 10 mg/kg HYD). When mice were given ip injections of HYD (0.25, 1, 2 and 10 mg/kg) 10 min prior to whole body irradiation, spleen stem cell survival after 6 Gy was increased (2.19 colonies in control animals vs 6.74 colonies per spleen in animals treated with greater than or equal to 2 mg/kg HYD), as was the LD50/30 dose (6.49 Gy [control] vs 9.00 Gy [10 mg/kg HYD]). The data provide evidence that PCr/Pi is a useful indicator of perfusion efficiency (and indirectly of hypoxic cell fraction) in FSaII tumors. These observations suggest that HYD may be a useful adjuvant for hyperthermic treatment of tumors and for potentiation of agents specifically toxic to hypoxic or nutrient-deprived cancer cells. HYD should be used with care in patients receiving radiation treatments or other therapies for which hypoxia can unfavorably affect treatment outcome.

Animals↗

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.

Animals↗

Effects of tumor necrosis factor-alpha on tumor blood flow and hyperthermic treatment.

The impact of recombinant human tumor necrosis factor-alpha (rhTNF-alpha), given alone or in combination with local hyperthermia, on perfusion and growth of a moderately rhTNF-alpha-sensitive rat tumor (DS-carcinosarcoma) was investigated. DS-carcinosarcomas were implanted into the hind foot dorsum of Sprague-Dawley rats. Tumor blood flow (TBF) was measured with the krypton-85 clearance technique. Treatment with either tumor necrosis factor-alpha (0.1-1.0 mg/kg) or hyperthermia (43.3 and 44.3 degrees C, 40 min) can decrease the perfusion of malignant tumors. The TBF reduction was fully established 2 h after rhTNF-alpha injection and lasted for at least 4 h. The application of local hyperthermia (T greater than 42 degrees C) 3 h after rhTNF-alpha administration further diminished tumor blood flow. Volume growth of the tumors was monitored during repeated treatment. rhTNF-alpha (0.2 and 1.0 mg/kg i.v.) combined with hyperthermia (43.3 and 44.3 degrees C, 40 min, starting 3 h after rhTNF-alpha injection) were given every third day from the fifth to the 20th day after tumor implantation. Monotherapies retarded tumor growth in a dose-dependent manner. Combined treatment was superior to either monotherapy leading to local tumor control in 40-50% of the animals treated. It is concluded that local hyperthermia can enhance the efficacy of rhTNF-alpha treatment by further reducing tumor perfusion.

Animals↗

Correlations between 31P-NMR spectroscopy and tissue O2 tension measurements in a murine fibrosarcoma.

Size-dependent changes in therapeutically relevant and interrelated metabolic parameters of a murine fibrosarcoma (FSaII) were investigated in vivo using conscious (unanesthetized) animals and tumor sizes less than or equal to 2% of body weight. Tumor pH and bioenergetics were evaluated by 31P nuclear magnetic resonance spectroscopy (31P-MRS), and tumor tissue oxygen tension (pO2) distribution was examined using O2-sensitive needle electrodes. During growth FSaII tumors showed a progressive loss of phosphocreatine (PCr) and nucleoside triphosphate (NTP) with increasing inorganic phosphate (Pi) and phosphomonoester (PME) signals. Ratios for PCr/Pi, PME/Pi, NTP/Pi, and phosphodiester/inorganic phosphate (PDE/Pi) as well as pH determined by 31P-NMR (pHNMR) and the mean tissue pO2 progressively declined as the tumors increased in size. The only relevant ratio increasing with tumor growth was PME/NTP. When the mean tissue pO2 value was plotted against pHNMR, NTP/Pi, PCr/Pi, PME/Pi, and PDE/Pi for tumor groups of similar mean volumes, a highly significant positive correlation was observed. There was a negative correlation between mean tumor tissue pO2 values and PME/NTP. From these results we concluded that 31P-MRS can detect changes in tumor bioenergetics brought about by changes in tumor oxygenation. Furthermore, the close correlation between oxygenation and energy status suggests that the microcirculation in FSaII tumors yields an O2-limited energy metabolism. Finally, a correlation between the proportion of pO2 readings between 0 and 2.5 mmHg and the radiobiologically hypoxic cell fraction in FSaII tumors was observed. The latter finding might be of particular importance for radiation therapy.

Animals↗

[The effect of recombinant human tumor necrosis factor alpha on malignant tumors in vivo. Physiopathologic basis for clinical oncology].

Effects of Recombinant Human Tumor Necrosis Factor-alpha on Malignant Tumors in vivo/Pathophysiological fundamentals for clinical oncology. The impact of recombinant human tumor necrosis factor-alpha (rhTNF-alpha; 6.6.10(6) U/mg protein) on growth, metabolism and perfusion of isotransplanted rat tumors (DS-carcinosarcomas) was investigated. Tumor growth was stimulated at low TNF doses (1 and 10 micrograms/kg), and significantly retarded at higher TNF dose levels (0.1 and 1.0 mg/kg). Growth changes were paralleled by variations in perfusion and metabolism. A reduced tumor blood flow enhanced the efficacy of a subsequent heat treatment. From these results, important implications for the clinical use of rhTNF-alpha are obvious (e.g., possible growth stimulation, timing of a combination therapy with other tumor treatment modalities).

Animals↗

Glucose uptake, lactate release, ketone body turnover, metabolic micromilieu, and pH distributions in human breast cancer xenografts in nude rats.

Glucose uptake, lactate release, ketone body utilization, spatial distribution of glucose, lactate, and ATP concentrations as well as tissue pH distributions were systematically investigated in s.c. and/or "tissue-isolated" human breast cancer xenografts in T-cell-deficient rnu/rnu rats. Large variations in all parameters were detected within and between tumors indicating a very nonuniform substrate turnover. Glucose was taken up by all xenografts. Glucose consumption rates increased with increasing glucose availabilities, implying that the glucose uptake is mainly determined by the efficiency of nutritive tumor blood flow. The average glucose uptake was 0.37 mumol/g/min in medullary and 0.26 mumol/g/min in squamous cell carcinomas of the breast. At wet weights below 5 g, medullary breast cancers consumed more glucose than squamous cell carcinomas (2P less than 0.05). Most tumors (97%) released lactate in an amount linearly related to glucose consumption. The lactate production of medullary (0.33 mumol/g/min) and squamous cell (0.31 mumol/g/min) breast cancers was similar. In general, the xenografts utilized ketone bodies. beta-Hydroxybutyrate was consumed by 82% and acetoacetate by 73% of the tumors, the uptake rates being linearly related to the respective availabilities. The mean uptake of beta-hydroxybutyrate was 3.48 nmol/g/min and that of acetoacetate 2.56 nmol/g/min. No significant differences were seen between medullary and squamous cell breast cancers. The beta-hydroxybutyrate/acetoacetate ratio in the tumor-venous blood rose with decreasing tumor blood flow indicating the development of hypoxia at advanced growth stages. Glucose, lactate, and ATP levels were all very heterogeneously distributed in medullary and squamous cell tumors as compared with normal tissue. No relationship was evident between the spatial distribution of concentrations of these three substrates. The xenografts were acidotic compared with pH values in normal subcutis. The mean tissue pH in medullary breast cancers was 6.81 +/- 0.25 (SD). Compared with these values, the tissue pH distribution in squamous cell breast cancers was shifted to significantly higher values. The mean pH of the latter tumors was 7.04 +/- 0.19 (2P less than 0.001). From the experimental data presented there is clear indication that the metabolism of the xenografts investigated was mainly determined by the efficiency of nutritive blood flow, i.e., by substrate availability, and not by the metabolic demand of the cancer cells.

Animals↗

Metabolic imaging in microregions of tumors and normal tissues with bioluminescence and photon counting.

A method has been developed for metabolic imaging on a microscopic level in tumors, tumor spheroids, and normal tissues. The technique makes it possible to determine the spatial distribution of glucose, lactate, and ATP in absolute terms at similar locations within tissues or cell aggregates. The substrate distributions are registered in serial cryostat sections from tissue cryobiopsies or from frozen spheroids with the use of bioluminescence reactions. The light emission is measured directly by a special imaging photon counting system enabling on-line image analysis. The technique has been applied to human breast cancer xenografts, to spheroids originating from a human colon adenocarcinoma, and to skeletal rat muscle. Preliminary data obtained indicate that heterogeneities in the substrate distributions measured are much more pronounced in tumors than in normal tissue. There was no obvious correlation among the three quantities measured at similar locations within the tissues. The distribution of ATP corresponded well with the histological structure of larger spheroids; values were low in the necrotic center and high in the viable rim of these cell aggregates.

Adenosine Triphosphate↗