High IGF-IR Activity in Triple-Negative Breast Cancer Cell Lines Correlates with Sensitivity to IGF-IR Inhibitor BMS-754807 in This Subtype of Human Breast Cancer

BACKGROUND: Evidence implicates insulin-like growth factor-I (IGF-I) signaling in the development and progression of breast cancer. Within the last few years several drugs targeting IGF-I receptor (IGF-IR) have entered clinical trials and are showing promising early results. BMS-754807 is a new small molecule inhibitor of IGF-IR in Phase 1 clinical trials.METHODS: Minimal and maximal IC50 to BMS-754807 for monolayer proliferation was determined for a panel of 30 breast cancer cell lines. Comparative gene expression analysis was performed using publicly available gene expression among the most resistant and sensitive cell lines. Q-RT-PCR was used to validate gene expression differences. Using the IGF gene signature, we scored each expression profile in a panel of cell lines and tumorgrafts, for correlation with the IGF-induced patterns. IGF-IR and pY-IGF-IR levels were determined in human tumorgrafts by immunohistochemistry.RESULTS: Among the different tumor cell lines, sensitivity to BMS-754807 varied widely from 0.1µM to 25µM. When defining cell lines as sensitive or resistant based on the median IC50, there was a strong enrichment for triple negative (TN; ERa-/PR-/HER2-) breast cancer cell lines in the sensitive group (11/15), while luminal breast cancer cell lines were generally resistant (11/15). We identified 136 differentially expressed genes between sensitive and resistance cell lines. Sensitive breast cancer cell lines preferentially express genes such as CAV1, and CAV2 while resistant cell lines were associated with high expression of ErbB3, and SPDEF. As luminal breast cancer cell lines were generally resistant to BMS-754807, we examined the role of estrogen and ERa on the sensitivity to BMS-754807. ERa mRNA levels strongly correlated with resistance to BMS-754807. Consistent with this, estrogen-withdrawal sensitized luminal breast cancer cells to BMS-754807. Previously, we developed an IGF-I gene signature that was derived from breast cancer cells stimulated with IGF-I, and reported that the signature strongly correlated with the TN subtype of human breast cancer. Consistent with this observation, we found that the IGF-I signature was high in TN breast cancer cell lines, and the IGF-I signature correlated with sensitivity to BMS-754807. To examine this further, we measured IGF-IR and pY-IGF-IR levels in four recently developed tumorgraft models of TN human breast cancer and found strong reactivity in half of the models. Interestingly, the tumorgraft (MC1) with the highest IGF-IR levels and activity showed the strongest enrichment for the IGF-I gene signature.CONCLUSIONS: In summary, our data indicates that the IGF-I pathway is highly active in TN breast cancer and this study provides the preclinical rationale for targeting IGF-IR in this subtype of human breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1132.

Complete IGF Signaling Blockade by the Dual-Kinase Inhibitor, BMS-754807, Is Sufficient To Overcome Tamoxifen and Letrozole Resistance In Vitro and In Vivo

Resistance to hormonal therapy is a clinically unmet need in breast cancer. IGF signaling has been identified as a major mechanism of resistance to hormonal therapy in breast cancer. As components of the IGF signaling pathway are expressed in most breast cancers, the development of IGF-1R monoclonal antibody (mAb) and tyrosine kinase inhibitors (TKI) are active areas of clinical investigations. A key distinction between the mAb and TKIs are their differences in their ability to inhibit the Insulin Receptor (InsR). While targeting the InsR with TKIs may have a theoretical liability of hyperglycemia, targeting only the IGF-1R may have the theoretical liability of incompletely blocking IGF signaling. As InsR isoform A expression, which can transduce IGF-II-mediated proliferation, is higher in breast cancers compared to normal breast tissue, we investigated whether IGF-1R or IGF-1R/InsR inhibition was sufficient for overcoming resistance to hormonal therapy. To determine the optimal combination strategies for clinical investigations, we tested the hypothesis that IGF signaling inhibition could overcome primary (or de novo/intrinsic) and secondary (or acquired/selected) resistance to hormonal therapy. For these studies, we used either hormone therapy-naïve or hormone therapy-resistant variants of the breast cancer model, MCF-7/AC-1, which has been engineered to stably express full-length human aromatase. We employed and compared a novel, potent dual kinase inhibitor of the IGF-1R and InsR, BMS-754807, which is currently in early clinical investigations, with the IGF-1R antibody mAb391. BMS-754807 has been shown to induce apoptosis more potently than mAb391 in Rh41 human rhabdomyosarcoma cells. In vitro, BMS-754807 demonstrated profound synergy in combination with tamoxifen and letrozole (median effect combination index <0.1). In vivo, BMS-754807 enhanced the anti-tumor activity of tamoxifen and letrozole in hormone-naïve tumors and induced regression of tumors resistant to tamoxifen or letrozole when combined with letrozole. This activity was not observed with mAb therapy, which resulted in greater up-regulation of InsR-A and erbB receptor expression and activation. This suggested a greater susceptibility to resistance pathways with mAb therapy. Dual IGF-1R/InsR blockade alone or in combination was tolerated by the animals and has no significant change in glucose homeostasis. Gene expression profiling experiments to compare the difference between the effects of tamoxifen in combination with BMS-754807 and with mAb revealed alternative pathway signaling is one of the potential mechanisms of resistance.In summary, combined hormonal therapy with BMS-754807 overcomes primary and secondary resistance to tamoxifen and letrozole and was well tolerated. IGF-1R blockade with a mAb alone is insufficient to overcome resistance and induces InsR over-expression. Thus, IGF signaling through either InsR or IGF-1R may be a major mechanism of resistance to hormonal therapy. These data suggest that blockade of IGF-1 and IGF-II from activation of IGF-1R and InsR, with agents such as BMS-754807 have promise in extending the benefits of hormonal therapy in breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 402.

Vergleich einer standardisierten Ernährungslösung (ZPE-Glukose/Elektrolyte^®) mit einer üblichen Ernährung im Intensivbereich

<i>Ziel:</i> Vergleich einer standardisierten Ernährungslösung mit einer selbst-gemischten Infusionstherapie bei Intensivpatienten einer chirurgischen Intensivstation; Untersuchung der standardisierten Ernährungstherapie auf Praktikabilität und Effizienz. <i>Design:</i> Prospektive randomisierte Studie. <i>Rahmen:</i> Chirurgisch-traumatologische Intensivstation einer Universitätsklinik. <i>Patienten:</i> Chirurgisch-traumatologische Patienten, die länger als 6 Tage auf der Intensivstation lagen. <i>Interventionen:</i> Gabe einer standardisierten Ernährungslösung im Ein-Liter-System (ZPE-GE) bzw. Gabe einer herkömmlichen, selbstgemischten Infusionslösung (hER). Bestim-mung von Stoffwechselparametern und Serum- bzw. Harnelektrolyten, zusätzlich Bestimmung von Blut- und Harnglukose, Harnstoffproduktionsrate, Triglyzeriden. <i>Ergebnisse:</i> Die beiden Patientengruppen waren sowohl in ihren physiologischen Daten als auch in der Schwere der Erkrankung miteinander vergleichbar, Komplikationen und Unverträglichkeiten konnten unter den angegebenen Regimen nicht beobachtet werden. Die Energie- (durchschnittlich 1202 kcal/Tag in der Gruppe hER versus 1331 kcal/Tag in der Gruppe ZPE-GE) und Substratzufuhren (Glukose: 228 versus 252 g/Tag; Aminosäuren: 56 versus 64 g/Tag) sind als ausge-glichen zu betrachten, es konnten keine Stoffwechselentgleisungen beobachtet werden. Die Elektrolytzufuhr (Natrium: 56 mmol/Tag in der Gruppe hER versus 92 mmol/Tag in der Gruppe ZPE-GE; Kalium: 65 versus 68 mmol/Tag; Phosphat: 15 versus 19 mmol/Tag) scheint in der Vollperiode nicht ganz optimal zu sein. <i>Schlussfolgerungen:</i> Die standardisierte Lösung scheint gegenüber den herkömmlichen Mischungen Vorteile zu haben: Sie erleichtert das Handling im Intensiv- und Postoperativbereich und verbessert Genauigkeit, Zeitersparnis und hygienische Bedingungen beim Umgang mit diesen Lösungen. Eine Infusionsmenge von 2000 ml (300 g Glukose und 100 g Aminosäuren) dieser Lösung erscheint als ausreichend, bei höherer Zufuhr könnte die Kohlenhydrat- und Aminosäurenzufuhr zu hoch liegen. Auch bei der Elektrolytzufuhr ist eine Begrenzung auf 2000 ml (120 mmol Natrium) angezeigt. Der Natriumanteil könnte auf 50 mmol/l reduziert werden, um ein entsprechendes Natriumloading zu verhindern, bei der Phosphatzufuhr ware eine Erhöhung auf 12 mmol/l empfehlenswert. Die Lösung kann zur standardisierten parenteralen Ernährung bei einem Großteil (ca. 80%) der postoperativen und posttraumatischen Patienten herangezogen werden, nur bei Extremsituationen müssen weiterhin die Einzelkomponenten (Glukose, Aminosäuren, Fette und Elektrolyte) speziell zusammengemischt werden, um metabolische Komplikationen zu verhindern.

[Lipid infusion in multiple trauma intensive care patients in the early phase of treatment]

OBJECTIVES

To study the metabolic effects of a high-dose fat infusion application in the early phase of total parenteral nutrition (TPN) after major trauma.

DESIGN

Prospective study in male patients after major trauma.

SETTING

Intensive care unit of the University Clinic.

PATIENTS

21 male, mechanically ventilated patients after major trauma.

INTERVENTIONS

Infusion of Elolipid 20% (Fa. Leopold, Graz, Austria), starting on the 3rd day after ICU admission (0.075 g/kg body weight/h) in 8 h. The dose was increased on the 5th day (0.125 g/kg BW/h) and on the 7th day (0.15 g/kg BW/h).

RESULTS

There was a pathologic rise in serum triglycerides on days 3, 5 and 7 during the infusion period. A serious diabetic metabolic state was shown on the 3rd day. No significant changes in urea production rate could be demonstrated after the high-dose fat infusion.

CONCLUSIONS

The reason for the decreased fat elimination in patients after major trauma after high-dose fat infusion (8 h) remains unclear (fat clearance or fat oxidation failure). Therefore the fat infusion should be started after normalization of the blood glucose level. Thus the fat infusion should be given continuously over 24 h to avoid serious metabolic complications.

Are hypotension and rash after atracurium really caused by histamine release?

A prospective, randomized, double-blind study was performed in 40 patients (ASA class I-III) treated with atracurium to ascertain whether histamine release caused hemodynamic or cutaneous changes. The treated group of 20 patients was premedicated with the H1 antagonist dimetindene (0.2 mg/kg) and the H2 antagonist ranitidine (1.25 mg/kg); the control group of 20 patients received saline. Six minutes after the induction of anesthesia with thiopental/fentanyl, patients received atracurium 0.5 mg/kg over 5 s. Plasma histamine levels were measured fluorometrically 5 min after administration of thiopental/fentanyl and 2 and 5 min after atracurium. Arterial blood pressure and heart rate were recorded every 2 min. Histamine levels (0.24 ng/mL) did not change significantly after thiopental/fentanyl. In the control group, 2 min after injection of atracurium, plasma histamine levels were 0.76 +/- 0.76 ng/mL, and in the antihistamine-treated group, 0.39 +/- 0.24 ng/mL (P < 0.05 control versus treated), suggesting that pretreatment with antihistamines may attenuate atracurium-induced histamine release. Systolic and diastolic blood pressure decreased significantly in both groups after thiopental (P < 0.05), but did not decrease further after the administration of atracurium. There were cutaneous manifestations in 7 of 20 patients in the control group and in none of the 20 patients treated with H1 and H2 antagonists (P < 0.0005). We conclude that atracurium caused modest histamine release in our patients but that the decrease in arterial blood pressure may have been due, in part, to thiopental. Cutaneous manifestations of histamine release did not correlate with hemodynamic events or with plasma histamine levels, but were prevented with antihistamine pretreatment.

Response of cerebrospinal fluid pressure to continuous positive airway pressure in volunteers

The effect of a 10-min period of continuous positive airway pressure (CPAP) of 12 cm H2O on lumbar cerebrospinal fluid pressure (CSFP), cerebral perfusion pressure (CPP), central venous pressure (CVP), mean arterial pressure (MAP), heart rate (HR), and end-tidal carbon dioxide (ETCO2) was studied in eight volunteers. CSFP increased (7 +/- 4 control vs 11 +/- 4 mm Hg; P < 0.001; mean +/- SD) and CVP increased (2 +/- 2 control vs 5 +/- 3 mm Hg; P < 0.001; mean +/- SD) when CPAP of 12 cm H2O was applied. CPP decreased slightly during CPAP (79 +/- 13 vs 74 +/- 19 mm Hg; P < 0.05; mean +/- SD), whereas MAP, HR, and ETCO2 remained unchanged. The findings of our study suggest that changes in CSFP and CPP due to moderate levels of CPAP, although statistically significant, are probably of only minor clinical importance.

Fettinfusion bei polytraumatisierten Intensivpatienten in der Frühphase der Behandlung

<i>Ziel:</i> Untersuchung der metabolischen Auswirkung einer Fettinfusion in steigender Dosierung in der frühen Phase der totalen parenteralen Ernährung (TPN). <i>Design</i>: Offene, prospektive Untersuchung an männlichen Patienten nach multiplem Trauma. <i>Rahmen</i>: Intensivstation einer Universitätsklinik. <i>Patienten</i>: 21 männliche, maschinell beatmete Patienten nach einem schweren Trauma. <i>Interventionen:</i> Fettinfusion (Elolipid 20%, Fa. Leopold, Graz, Osterreich) vom 3. Aufnahmetag an in steigender Dosierung: 0,075 g/kg Körpergewicht/h am 3. Tag; 0,125 g/kg KG am 5. Tag und 0,15 g/kg KG am 7. Tag i. v. über jeweils 8 h. <i>Ergebnisse</i>: Die Triglyzeridwerte stiegen am 3. Behandlungstag während und nach der Infusion signifikant an, während der prozentuale Anstieg (gewichtet auf 1 g/kg KG) am 5. Behandlungstag nur unter laufender Fettzufuhr signifikant war. Die Werte nach Beendigung der Fettzufuhr lagen in alien Fallen niedriger als unter laufender Fettzufuhr. Eine Hyperglykämie konnte besonders am 3. Tag beobachtet werden. Es konnte keine Senkung der Harnstoff-Produktionsrate nach hochdosierter Fettgabe beobachtet werden. <i>Schlußfolgerungen</i>: Unter der vorgegebenen Fettzufuhr dürfte es zu einer Überschreitung der Fettelimination gekommen sein, wobei nicht geklärt ist, ob die Clearance oder die Oxidation vermindert war. Das gestörte Verhalten im Glukose-stoffwechsel scheint diese Annahme zu unterstützen. Daraus ergibt sich unseres Erachtens die Notwendigkeit einer entsprechenden Dosisanpassung und einer kontinuierlichen Applikation von Fett über 24 h, wenn die Kohlenhydratzufuhr bedarfsdeckend erfolgt und die Glukosewerte sich im Normbereich befinden, um bei schwer traumatisierten Patienten metabolische Störungen zu vermeiden.

Laminin adhesion-selected primary human colon-cancer cells are more tumorigenic than the parenteral and nonadherent cells

Laminin has been shown to promote the malignant phenotype and the level of the 32/67 Kd laminin receptor has been found to correlate with Dukes' staging of colon cancer. A biopsy of a Dukes' stage B2 human colon carcinoma formed a tumor in a nude mouse after coinjection with Matrigel. The parental tumor and the murine tumor appeared identical at the histological level. A cell line LCC-C1 was established from the murine tumor. The cell line appeared moderately differentiated although it did not produce mucin in vitro; however, the xenograft in vivo did produce low levels of mucin. Laminin adherent and non-adherent cell lines were selected. The parental and the laminin-selected cell subclones adhered equally well to plastic and to fibronectin and showed similar growth rates on plastic. When injected subcutaneously into nude mice, the laminin-adherent cells formed relatively undifferentiated tumors that were twice as large as the parental cell tumors whereas the laminin non adherent cells formed very small, but highly differentiated tumors. These data demonstrate that subpopulations of tumor cells which differ in their tumorigenic properties can be selected based on their adhesion to laminin and thus provide models for studying the mechanisms of tumor growth.

Spirometry, blood gas analysis and ultrasonography of the diaphragm after Winnie's interscalene brachial plexus block

Ten patients with healthy lungs were subjected to radiology, sonography, spirometry and blood gas analysis before and after an interscalene brachial plexus block prior to shoulder surgery. Winnie's interscalene block induced ipsilateral hemidiaphragmatic paresis that was confirmed by radiology and sonography. Changes in forced expiratory vital capacity (FVC), forced expiratory volume (FEV1) and peak expiratory flow rate (PEFR) were significant and PaO2 declined by an average of 1.3 kPa. These changes should not cause further clinical symptoms in sitting patients with unaffected lungs. In patients with pulmonary disease, this method of nerve block should be limited to cases for which there is a clear indication.

Expression of transforming growth factor alpha antisense mRNA inhibits the estrogen-induced production of TGF alpha and estrogen-induced proliferation of estrogen-responsive human breast cancer cells

To ascertain if 17 beta-estradiol (E2)-induced proliferation could be attenuated by blocking the expression of endogenous transforming growth factor alpha (TGF alpha), estrogen receptor (ER)-positive, estrogen-responsive MCF-7 or ZR-75-1 cells and ER-negative, estrogen-nonresponsive MDA-MB-468 or HS-578T cells were infected with a recombinant amphotropic, replication-defective retroviral expression vector containing a 435 base pair (bp) Apa1-Eco R1 coding fragment of the human TGF alpha cDNA oriented in the 3' to 5' direction and under the transcriptional control of an internal heavy metal-inducible mouse metallothionein (MT-1) promoter and containing the neomycin (neo) resistance gene. E2-stimulated expression of endogenous TGF alpha mRNA was inhibited by 4-5-fold, and the production of TGF alpha protein was inhibited by 50-80% when M-1 mass-infected MCF-7 or MZ-1 mass-infected ZR-75-1 cells were treated with 0.75-1 microM CdCl2, whereas in comparably treated parental MCF-7 or ZR-75-1 cells there was no significant effect upon these parameters. E2-stimulated anchorage-dependent growth (ADG) and anchorage-independent growth (AIG) of the M-1 or MZ-1 cells was inhibited by 60-90% following CdCl2 treatment. In contrast, neither the ADG nor AIG of the parental noninfected MCF-7 or ZR-75-1 cells that were maintained in the absence or presence of E2 was affected by comparable concentrations of CdCl2. The ADG and AIG of TGF alpha antisense MD-1 mass-infected MDA-MB-468 cells that express high levels of endogenous TGF alpha mRNA were also inhibited by 1 microM CdCl2, whereas the ADG and AIG of MH-1 mass-infected HS-578T cells, a TGF alpha-negative cell line, were unaffected by CdCl2 treatment. These results suggest that TGF alpha may be one important autocrine intermediary in regulating estrogen-induced cell proliferation.

[Effects of short-term application of recombinant human growth hormone on urea production rate in patients in the early postoperative phase]

OBJECTIVE

To determine the effect of short-term recombinant human growth hormone (rhGH) administration on urea production rate (UPR), N balance and aminograms.

DESIGN

Prospective, double-blind placebo-controlled study.

SETTING

Intensive care unit of a University Hospital.

PATIENTS

20 adult patients after major abdominal surgery.

INTERVENTIONS

Postoperative substitution of rhGH (Saizen, Serono, Aubonne, CH) in a dose of 0.15 IE/kg BW for 3 days. The serum levels of hGH, insulin-like growth factor-1 (IGF-1), ACTH and cortisol were measured as well as the amino acids in plasma. The degree of catabolism was calculated according to Woolfson's formula, which is based on the UPR, and by calculation of the cumulative N balance.

RESULTS

With exception of proline, the plasma amino acids between the groups receiving active substance and total parenteral nutrition (TPN) and those receiving placebo and TPN did not differ significantly. Neither was there a significant difference between the groups for any other parameter measured. The UPR and IGF-1 levels showed only a tendency towards higher values as compared with the placebo group (UPR verum group, values in g/day: 1st measurement, 29.8 +/- 16.7; 2nd measurement, 28.3 +/- 17.7; 3rd measurement, 32.1 +/- 19.1; 4th measurement, 33.1 +/- 21.2. UPR placebo, values in g/day; 1st measurement, 32.6 +/- 23.9; 2nd measurement, 30.8 +/- 17.9; 3rd measurement 41.6 +/- 28.7; 4th measurement, 47.3 +/- 29.5. IGF-1 verum group, values in nmol/l; 1st measurement, 25.7 +/- 19.2; 2nd measurement, 44.8 +/- 23; 3rd measurement, 52.4 +/- 30; 4th measurement, 54.3 +/- 20. IGF-1 placebo, values in nmol/l; 1st measurement: 22.9 +/- 11.7; 2nd measurement, 37.0 +/- 19.4; 3rd measurement, 38.4 +/- 21.4; 4th measurement, 40.0 +/- 23.0). The ACTH-cortisol axis was only slightly depressed in the group receiving active substance.

CONCLUSIONS

We conclude that short-term rhGH administration over 3 days is not capable of significantly reducing the UPR in postoperative patients, but we cannot exclude a significant difference between rhGH group and placebo after a longer administration period.

Effekte einer kurzzeitigen Applikation von rekombinantem humanem Wachstumshormon auf die Harnstoffproduktionsrate von Patienten in der frühen postoperativen Phase

<i>Ziel:</i> Das Ziel dieser Studie war es, die Wirkung einer kurzzeitigen adjuvanten Therapie mit rekombinantem humanem Wachstumshormon (rhGH) auf die Harnstoffproduktionsrate (HPR) und die kumulative N-Bilanz bei Patienten im Post-aggressionsstoffwechsel nach großen chirurgischen Eingriffen zu untersuchen. Design: Prospektive randomisierte Doppelblindstudie. Rahmen: Intensivstation einer Universitätsklinik. Patienten: 20 Patienten nach großen abdominellen Eingriffen. <i>Interventionen:</i> Postoperative Substitution mit rhGH (Saizen^®, Fa. Serono, Aubonne, CH) in einer Dosierung von 0,15 IE/kg KG über 3 Tage. Gemessen wurden die Serumkonzentrationen von hGH, IGF-1, ACTH, Cortisol und die Plasmaamino-gramme. Der Grad der Katabolie wurde mittels der HPR, nach der Formel von Woolfson, und der kumulativen N-Bilanz errechnet. <i>Ergebnisse:</i> Die Plasmaaminosäuren blieben bis auf das Prolin zwischen Plazebo und Verumgruppe ohne statistisch signifikanten Unterschied. Die IGF-1-Serumspiegel waren gegenüber der Plazebogruppe nur im Trend erhöht (IGF-1-Verumgruppe, Werte in nmol/l: 1. Messung 25,7 ± 19,2; 2. Messung 44,8 ± 23; 3. Messung 52,4 ± 30; 4. Messung 54,3 + 20. IGF-1-Plazebogruppe, Werte in nmol/l: 1. Messung 22,9 ± 11,7; Messung 37,0 ± 19,4; 3. Messung 38,4 ± 21,4; 4. Messung: 40,0+23,0), bei gleichzeiti-ger leichter Erniedrigung der HPR (HPR-Verumgruppe, Werte in g/Tag: 1. Messung 29,8 ± 16,7; 2. Messung 28,3 + 17,7; 3. Messung 32,1 ± 19,1; 4. Messung 33,1 + 21,2. HPR-Plazebogruppe, Werte in g/Tag: 1. Messung 32,6 ± 23,9; 2. Messung 30,8+17,9; Messung 41,6 ± 28,7; 4. Messung 47,3 + 29,5). Die ACTH-Cortisol-Achse war in der Verumgruppe nur gering gedämpft. <i>Schlußfolgerungen:</i> Die kurzzeitige Applikation von rhGH über 3 Tage ist nicht in der Lage, die HPR bei chirurgischen Patienten in der unmittelbar postoperativen Periode signifikant zu reduzieren. Ein positiver Effekt bei längerem Applikations-zeitraum kann jedoch durch die vorliegenden Daten nicht ausgeschlossen werden.

Fentanyl increases cerebrospinal fluid pressure in normocapnic volunteers

In a double blind randomized study, the effect of fentanyl 1 microgram kg-1 i.v. or placebo on mean lumbar cerebrospinal fluid pressure (CSFP), mean arterial pressure, cerebral perfusion pressure, transcutaneous PCO2 and heart rate was studied in 10 spontaneously breathing volunteers in the lateral decubitus position via a 22-gauge spinal needle inserted into the subarachnoidal space at level L3/L4. Fentanyl increased mean CSFP (+/- SD) from 12.4 +/- 2.7 mmHg to 16.0 +/- 2.3 mmHg (P < 0.05) without significant changes in the other variables. No significant changes in any of the measured variables were seen after administration of placebo. Cerebral perfusion pressure decreased significantly after fentanyl (P < 0.05).

Additive effects of c-erbB-2, c-Ha-ras, and transforming growth factor-alpha genes on in vitro transformation of human mammary epithelial cells

MCF-10A cells are a spontaneously immortalized untransformed human mammary epithelial cell line. We have previously shown that overexpression of a human point-mutated c-Ha-ras proto-oncogene, the rat c-neu (c-erbB-2) proto-oncogene, or the human transforming growth factor-alpha (TGF-alpha) gene in MCF-10A cells leads to in vitro transformation of such cells. To ascertain whether the introduction of two of these genes into MCF-10A human mammary epithelial cells induces a completely tumorigenic phenotype, we infected MCF-10A Ha-ras and MCF-10A TGF-alpha cells with a recombinant retroviral vector containing the human c-erbB-2 proto-oncogene and the hygromycin-resistance gene. Ten MCF-10A TGF-alpha/c-erbB-2 (MCF-10A TE) and 10 MCF-10A Ha-ras/c-erbB-2 (MCF-10A HE) hygromycin-resistant clones were randomly selected and expanded into cell lines. MCF-10A TE and MCF-10A HE clones expressed a 10-fold to 40-fold increase in p185 erbB-2 protein levels compared with parental uninfected cells. These cells exhibited a fourfold increase in their growth rate in serum-free medium and showed a strongly reduced mitogenic response to exogenous epidermal growth factor or TGF-alpha compared with MCF-10A cells. Moreover, both MCF-10A TE and MCF-10A HE clones exhibited a fivefold to 20-fold higher cloning efficiency in soft agar than MCF-10A Ha-ras, MCF-10A c-erbB-2, or MCF-10A TGF-alpha clones. However, neither MCF-10A TE nor MCF-10A HE cells were able to grow as tumors in vivo when they were injected into nude mice. These results suggest that c-Ha-ras, c-erbB-2, and TGF-alpha genes have an additive effect on the in vitro transformation of an immortalized human mammary epithelial cell line, but that additional genetic changes such as activation of other proto-oncogenes or inactivation of a tumor suppressor gene may be necessary to elicit a fully tumorigenic phenotype.

Atrial natriuretic peptide (ANP), aldosterone, angiotensin II and renin in the 'low T3 syndrome' in organ donors

The present prospective study was conducted in order to investigate the effect of an acute decrease in serum T3 levels on ANP, aldosterone, angiotensin II, renin and ADH. All patients showed a pathologic TRH stimulation test prior to organ harvesting. Our patients developed secondary T3 hypothyroidism of different severity dependent on intensive care unit (ICU) stay. T3 values in group 1 (ICU stay > or = 77 h) were smaller than 70 ng/dl, those of group 2 (ICU stay < or = 53 h) were greater than 70 ng/dl. In both groups a severe elevation of plasma renin activity was measured, with almost high-normal values for ANP in group 1 and slightly elevated values in group 2 [not significant (n.s.)]. Results demonstrate that, contrary to patients who are not critically ill, brain-dead patients develop a dissociation of the renin-angiotensin-aldosterone mechanism. No statistical significant difference was found between the groups in serum levels of ADH and aldosterone. This endocrine dissociation, however, seems to have no clinical significance with regard to organ function after transplantation in kidney recipients.

Endocrine abnormalities in severe traumatic brain injury--a cue to prognosis in severe craniocerebral trauma?

Patients with severe craniocerebral trauma (sCCT) display metabolic and endocrine changes. The question is raised whether hormonal patterns give cues to the prognosis of outcome or not. In 21 patients the function of the adrenocortical, gonadal, thyroid and human growth hormone (hGH)-insulin system was assessed. LH, FSH, TSH, prolactin and hGH were stimulated. 3 groups of patients were formed. Group I: patients in acute phase with a Glasgow Coma Score (GCS) more than 6 (group Ia) and less than 6 (group Ib). Group II: patients in transition to traumatic apallic syndrome (TAS). Group III: patients with full-blown or resolving TAS. The values of group Ia comprised low T3, T4 and testosterone, elevated insulin, normal hGH. Group Ib had hypothyroid T3 and T4 and an attenuated response of LH, TSH, prolactin and hGH to stimulation. Group III: there was seen an endocrine normalisation with elevated T4 and TBG and an altered response of hGH and prolactin to stimulation. Endocrine abnormalities were not helpful in predicting which course, either to better or to worse, a given patient would follow.

[The automated determination of the dibucaine number using the Greiner G450 selective analyzer. A routine parameter of significance?]

Patients who are homozygous for an atypical pseudocholinesterase enzyme (PCHE) suffer a prolonged neuromuscular block after succinylcholine application. In order to determine which patients have atypical PCHE preoperatively, an automated method using the Greiner G450 analyzer was developed.

PATIENTS AND METHODS

The contribution of blocked and unblocked PCHE by dibucaine hydrochloride (optimal concentration 10(-4) mol/l;) was determined in 113 patients (ASA groups 1-2) and the dibucaine number (DN) was evaluated.

RESULTS

According to the DN, the patients were subdivided into three groups: group A (PCHE 5.01 +/- 1.64 kU/l, DN 74.47 +/- 0.87); group B (PCHE 4.28 +/- 3.41 kU/l, DN 64.95 +/- 3.41); group C (PCHE 1.33 +/- 0.54 kU/l, DN 13.08 +/- 2.19;). PCHE and DN of group A corresponded with normal standard values, whereas the patients in groups B and C could be considered to be patients with heterozygous and homozygous atypical PCHE, respectively.

CONCLUSIONS

Our data indicate that an automated analysis of blocked and unblocked PCHE with the Greiner G450 can be easily done in a routine laboratory. By interpreting the DN, the possible risks of delayed succinylcholine degradation can probably be prevented.

High-frequency pulsation (HFP) in a patient with Guillain-Barré syndrome

A patient with Guillain-Barré syndrome (GBS) developed a respiratory crisis despite recurrent treatment with plasma exchange. Thus mechanical ventilatory support became necessary. As an alternative to conventional ventilatory techniques high-frequency pulsation (HFP), a modified high-frequency jet-ventilation technique was used. According to the observations HFP may be a valuable technique for the continuous adaptation to the patient's individual respiratory demands in GBS.

The secretion of human growth hormone stimulated by human growth hormone releasing factor following severe cranio-cerebral trauma

Patients suffering from severe cranio-cerebral trauma show alterations of the secretory patterns of thyroid stimulating hormone (TSH) and human growth hormone (HGH) which may be of prognostic significance. We studied 10 patients following severe brain injury and prospectively compared a new synthetic human growth hormone releasing factor (HGHRF) test with the thyrotropin releasing hormone (TRH) test. On admission, all patients had a Glasgow Coma Scale score of 3 or 4. All patients had a low T3 syndrome. In the patients who died the TSH response after stimulation with TRH was also absent. In the patients who survived a significant TSH increase was observed (p less than 0.05). In comparison to the patients who died those who survived showed a significant (p less than 0.001) HGH increase after HGHRF stimulation. This test might be useful as an additional tool in establishing early prognosis in patients with severe brain injury.

[The behavior of hGH (human growth hormone) and somatomedin C following anesthesia induction with propofol in comparison with diazepam and thiopental]

It was the aim of present study to examine possible interactions between human growth hormone (hGH) and Somatomedin C (SmC), when inducting anaesthesia with propofol in healthy patients. Moreover these effects of propofol should be compared with that of diazepam and thiopentone. 30 patients scheduled for elective plastic-surgery were divided randomly into 3 groups. Induction of anaesthesia was performed in group 1 with diazepam, in group 2 with thiopentone and in group 3 with propofol. Measurements of hGH, SmC as well as blood glucose were performed at 4 different given times: (1.) preoperatively, (2.) 15 minutes, (3.) 30 minutes, (4.) 60 minutes after inducting anaesthesia. Diazepam and thiopentone lead to increases in hGH secretion already in a very early phase after induction of anesthesia (15 minutes) and remained on elevated level. Concentrations of Somatomedin C, as well as of blood glucose, however, remained unchanged during the whole observation period. In comparison to that findings propofol did not show any influence on hGH and consecutively on Somatomedin C activity at any time. Based on our results we can conclude that propofol should be the induction-agent of choice predominantly when anaesthetizing patients with unknown hormonal state (outpatients scheduled for operation).

Effect of prolonged sedation with propofol on serum triglyceride and cholesterol concentrations

We compared changes in serum lipid concentrations in ICU patients receiving a 3-day continuous infusion of propofol with those in patients receiving conventional sedation. No adverse effects were observed and the serum lipid concentrations were not significantly influenced by propofol. It is concluded that propofol might be a suitable agent for long-term sedation in the ICU, although serum lipid concentrations should be monitored throughout its administration.

[Response of human growth hormone to anesthesia induction with propofol]

Although there are distinct differences in both pharmacokinetics and chemical structure, propofol has sedative effects similar to those of benzodiazepines. Both diazepam and thiopental, commonly used agents for inducing anaesthesia, show some typical neuroendocrine effects such as liberation of human growth hormone (hGH) in addition to their well-known influences on the cardiovascular system. It was our aim to examine the endocrine response of hGH after induction of anaesthesia with propofol and to compare any possible effects with those of diazepam and thiopental. The study was performed on 30 non-premedicated patients, who underwent plastic-surgery (mean age: x = 35 +/- 8.3 years, mean body weight: x = 68.9 +/- 23.2 kg). No signs of endocrine disturbances were found in the patients prior to the study. Patients were divided in a random fashion into 3 groups of 10 persons each: In group 1 propofol was given in a bolus injection (2 mg/kg) and then by infusion for a period of 10 min (0.2 mg/kg/min). In group 2 diazepam (0.3 mg/kg) and in group 3 thiopental (5 mg/kg) were administered as a bolus to induce anesthesia. All patients were intubated immediately after induction of anesthesia and then relaxed using vecuronium (1 mg/kg). Ventilation was performed mechanically during the entire operative period (N2O/O2 - FiO2:0.33, tidal volume 10 ml/kg, respiratory rate: 14/min). To maintain anesthesia halothane (0.5-1.0 vol.-%) and meperidine (0.75 mg/kg) were added 15 min after induction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Modification of catabolic metabolism in patients with sepsis and cranio-cerebral injuries by administration of human growth hormone]

Patients with hyperdynamic symptoms of a severe sepsis and patients after severe head injury show remarkable metabolic disturbances, which become apparent in a persistent catabolic stage. This was found in 17 septic patients (group I) and in 20 patients after severe head injury (group II), who were studied for a period of 10 days. During this time the urea production rate (UPR) and the catabolic index (CI) were measured. After a preliminary period of 5 days a stimulation test of hGH secretion using arginine was carried out to estimate the secretion of hGH, insulin and blood glucose. After this stimulation test a substitution therapy using 0.05 IU/kg B.W. i.m. hGH (Crescormon, Kabi Vitrum, München) was applied to 11 patients in group I (group Ia) and in 8 patients in group II (group IIa) who were then compared with patients without substitution therapy. The mean values of hGH basic secretion were the same in all groups and were within the normal range. 30 min after stimulation it was possible to identify a distinct response pattern; 90 min after stimulation there was no significant response. All groups showed significantly elevated levels of insulin; no further elevation after stimulation was observed. The blood glucose levels in all groups remained within the normal range at all times. All the groups were similar regarding behavior of the investigated parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

[The behavior of free thyroxine and triiodothyronine concentrations after short-term balanced inhalation anesthesia]

Acute changes involving the hormones thyroxine (T4) and triiodothyronine (T3) followed by hyper -or hypothyroid crises will lead to both cardiovascular and metabolic disorders. Due to highly sensitive mechanisms controlling central hormonal production and peripheral enzymatic conversion (c.g. T4 to T3), numerous pharmacologically effective substances will influence the kinetics of these hormones. Thus, agents routinely used in anesthetic practice and their metabolites may disturb hormonal regulation in particular due to their central effectiveness [1, 2,5-7]. Based on this premise, it was our goal to search for anesthetic-induced hormonal changes in euthyroid patients living in a goiter-endemic area scheduled for short, elective orthopedic operations. Investigations were done in 21 outpatients (mean age: 24 years, mean body wt.: 64 kg) undergoing minor surgical procedures of the extremities. No clinical signs of thyroid disturbances could be observed preoperatively in the patients. Immediately after intravenous premedication (meperidine HCl 0.75 mg/kg and atropine 0.25 mg), anesthesia was induced (thiopentone 5 mg/kg) and continued by inhalation via face; mask using volatile agents: halothane, isoflurane, or enflurane (O2: N2O; FiO2 = 0.33). According to the anesthetic agent administered (halothane, isoflurane, enflurane), patients were divided into three groups of 7 patients each as listed in Table 1. Blood samples to determine free serum T4 (fT4) and T3 (fT3) as an expression of biologically available T4/T3, unconjugated to transport globulins, were drawn twice: immediately before premedication; and postoperatively after the patient had regained consciousness.(ABSTRACT TRUNCATED AT 250 WORDS)

Interactions between estrogens, prolactin, and growth hormone on the growth of N-nitrosomethylurea-induced rat mammary tumors

Rats bearing N-nitrosomethylurea-induced mammary tumors regressing after ovariectomy were assigned to control or treatment groups. All control tumors continued to regress, while the serum prolactin levels were subnormal. Estrogen replacement stimulated tumor regrowth, and increased the serum prolactin. Pergolide further suppressed the postovariectomy serum prolactin, and all tumors continued to regress. When estrogen and pergolide were given together, 32% of tumors progressed despite low serum prolactins. Ovine prolactin, delivered to ovariectomized rats at a rate of 40 micrograms/hr, caused 3 of 10 tumors to progress, 3 to become static, and 4 to continue regression. Prolactin also maintained the growth of 4 of 8 tumors after hypophysectomy, and arrested regression of 3 others. Posthypophysectomy regression was also prevented and growth maintained by the simultaneous administration of estrogen and growth hormone.

Effects of progesterone administration on N-nitrosomethylurea-induced rat mammary carcinogenesis

N-Nitrosomethylurea (NMU), 4 mg/100 g body wt, was given to female Sprague-Dawley rats by i.v. injection on 2 occasions, 4 weeks apart. One group of 20 animals also received 5 mg of progesterone s.c. on the morning before, of and after each NMU dose (acute progesterone treatment). A second group of 21 rats was given progesterone 2.5 mg twice a day throughout the experiment commencing 7 days before the first dose of NMU (chronic progesterone treatment). The third group of 20 animals comprised the NMU-exposed controls. The latent period for mammary tumor development was reduced and the number of tumors per rat was increased by the acute progesterone treatment. The final mammary tumor incidence for the chronic progesterone treatment group (62%) was lower than that of the controls (85%) and the acute progesterone-treated rats (80%), and tumor multiplicity was less. Estrogen receptor levels were significantly higher in tumors from the chronic progesterone group than in those from the acute progesterone-treated animals (P less than 0.01), and progesterone receptor levels were lower in comparison to either of the other 2 groups. Serum progesterone concentrations were subnormal in the NMU-exposed controls but the estrogens were unaffected. The acute progesterone-treated rats also had reduced serum progesterone levels when compared with normal animals, although they were significantly higher than those of the NMU-exposed controls (P less than 0.01). Extremely high serum progesterone levels in rats treated chronically with progesterone were accompanied by reduced estrogen concentrations. Serum prolactin levels were elevated in the NMU-exposed controls and chronic progesterone-treated groups compared with non-NMU-exposed normal rats, while growth hormone concentrations were reduced by progesterone administration. All 3 NMU-exposed groups had elevated serum TSH levels.

Rat mammary carcinoma regressions during suppression of serum growth hormone and prolactin

Female rats bearing N-nitrosomethylurea-induced mammary carcinomas were treated with pergolide mesylate to suppress serum prolactin. The drug was given alone, or with somatostatin, 20 micrograms/hr delivered by osmotic minipump for 7 days to suppress serum growth hormone. Tumour regressions did not occur with pergolide alone, but did so promptly in all of 5 rats when growth hormone levels were also suppressed by somatostatin. A potent long-acting agonistic analogue of somatostatin, L362,823 produced similar tumour regressions at a dose of 5 micrograms/hr when given with pergolide, but was ineffective alone. This dose completely prevented the episodic release of pituitary growth hormone.