Kjell Grankvist

Depletion of intracellular potassium ions (K+) is necessary for cells to shrink, induce DNA fragmentation and activate caspases, events which are features of apoptosis. We used 86Rb+ as a K+ analogue to evaluate the possibility of pharmacologically depleting human pulmonary mesothelioma (P31) and small cell lung cancer (U1690) cells of K+, for future use in studies of apoptosis induction. The Na+, K+, 2CI(-)-cotransport inhibitor bumetanide transiently inhibited 86Rb+ influx, but when combined with the Na+, K+, ATPase pump inhibitor ouabain there was a marked and lasting (up to 6 h) 86Rb+ influx inhibition. Cellular K+ efflux was augmented by amphotericin B, digitonin and nigericin. Amphotericin B was an effective 86Rb+ efflux stimulator with low cytotoxicity, whereas digitonin caused cell detachment and nigericin increased LDH release in the U1690 cell line, indicating considerable toxicity of the drugs. It is possible to efficiently reduce intracellular K+ by persistent K+ influx ...

Depletion of intracellular potassium ions (K+) is necessary for cells to shrink, activate caspases and induce DNA fragmentation, events which are features of apoptosis. Here we describe a 96-well plate method using the cell permeable form of K+ binding benzofuran isophtalate (PBFI-AM) to measure intracellular K+ content in relation to untreated control. Cultured human pulmonary mesothelioma cells (P31) and small-cell lung cancer cells (U1690) were treated with K+ flux modulators in order to deprive the cells of intracellular K+. The combination of K+ influx inhibition with 10 micromol/L bumetanide plus 10 micromol/L ouabain and K+ efflux stimulation with 3 mg/L amphotericin B or 5 micromol/L nigericin efficiently reduced the intracellular K+ content after 3 h. Manipulation of K+ fluxes with subsequent intracellular K+ depletion induced apoptosis of lung cancer cells, as detected by caspase-3 activity after 3 h K+ depletion followed by 24 h proliferation and TUNEL positive staining a...

Pregnancy, parity, and circulating steroid hormone levels are associated with risk of breast cancer, but little is known about hormone concentrations during pregnancy and subsequent breast cancer risk. We evaluated early pregnancy (<140 days gestation) serum estradiol, estrone, progesterone, and testosterone and breast cancer risk in a nested case-control study in the Finnish Maternity Cohort. The cohort includes 98% of pregnancies registered in Finland since 1983. Individuals with samples collected in the first pregnancy leading to a live birth were eligible. Breast cancer cases (n = 1,199) were identified through linkage with the Finnish Cancer Registry; 2,281 matched controls were selected using incidence density sampling. ORs were calculated using conditional logistic regression. Hormone concentrations were not associated with breast cancer overall. Estradiol was positively associated with risk of breast cancer diagnosed age <40 [4th vs. 1st quartile OR 1.60 (1.07-2.39); P...

Intraventricular haemorrhage (IVH) is a major problem in premature infants. Our objective is to assess the early predictive value of vascular endothelial growth factor (VEGF) for development of IVH and management of its squeal in preterm neonates. We prospectively studied 150 preterm neonates (PT) less than 34 weeks gestation. Fifty of them completed the study. 30/50 developed IVH during follow up, and 20 did not. First 24 hours, and 3(rd) day serum samples were collected. Cerebrospinal fluid (CSF) samples were withdrawn for 10 IVH patients. Serum VEGF; both samples were increased in IVH compared to non-IVH group (P=0.001). PHVD-group (n=10) had higher VEGF in both samples than resolved IVH (P=0.004), (P=0.005). While, VEGF increased in the IVH group 2(nd) sample compared to 1(st) (P=0.000), it decreased in non-IVH group, P=0.033). Each 1 unit increase in 1(ST) VEGF increased the risk of occurrence of IVH by 1.6%. 3(rd) day VEGF at a cut-off value of 135 pg/ml is 96% sensitive and 100% specific to predict PHVD. Serum VEGF inversely correlated with TLC, pH, PO(2) and HCO(3), and positively correlated with PCo(2) and FiO(2). Serum VEGF predicts development of IVH and PHVD in PT neonates. Also, high CSF level of VEGF could predict the need for permanent shunt placement.

Intracranial meningiomas are often complicated by peritumoral vasogenic cerebral edema, which appears to result from increased microvascular permeability and extravasation of proteinaceous and plasma fluid into the adjacent peritumoral space. The source of such edema has long been mysterious. The contents of this paper support the concept that vascular endothelial growth factor (VEGF) production plays a significant role in edema formation. Vascular endothelial growth factor messenger RNA expression has been found in a wide range of intracranial neoplasms, including malignant gliomas, metastatic melanomas, meningiomas, and other benign tumors. Several studies have confirmed the importance of VEGF in tumorigenesis, neovascularization, and edema production. This study tests the hypothesis that the presence of peritumoral edema in meningiomas is positively correlated with increased expression of VEGF mRNA. To investigate this hypothesis, 31 meningioma specimens were subjected to Northern blot analysis, hybridization with a complementary DNA VEGF probe, and laser densitometry to determine the relative levels of VEGF mRNA expression. Magnetic resonance imaging was then used in a double-blind fashion to correlate the neuropathological tissue samples with the presence of preoperative peritumoral edema. Of 31 patients studied, 14 exhibited no edema and 17 exhibited some level of peritumoral fluid accumulation. There was a marked increase in VEGF expression in patients with edema (p = 0.0004, Wilcoxon-Mann-Whitney rank-sum test). Meningiomas with peritumoral edema exhibited 3.4 times the level of VEGF mRNA as those without edema. These data demonstrate a strong link between VEGF mRNA expression and peritumoral edema and indicate that VEGF expression is an important factor in the etiology of edema around meningiomas.

To determine whether glycemic control of patients with diabetic retinopathy (DR) due to type 2 diabetes was related to VEGF plasma levels. The prospective study included 30 patients with DR due to type 2 diabetes. Retinopathy was classified according to the international clinical DR disease severity scale. The concentrations of VEGF in the blood plasma were measured by ELISA. Glycosylated hemoglobin (HbA1c) was assessed all patients. Results were reported as DCCT/NGSP-HbA1c (%) values. The median plasma level of VEGF was 34.5 (range 15-217) pg/ml. Median HbA1c was 7.5 (range 5.3-10.6). The highest individual plasma VEGF measurements were found in patients with severe non-proliferative DR. HbA1c levels revealed a significant correlation with plasma VEGF concentrations (r = 0.573, p = 0.001). Age (r = 0.097, p = 0.611), gender (r = -0.315, p = 0.09) and severity of DR (r = 0.256, p = 0.172) were with no significant relationship to the VEGF measurements. Poor glycemic control is positively correlated with increased levels of plasma VEGF in patients with type 2 diabetes. As normalization of HbA1c is one of the most effective ways to prevent progression of DR and VEGF has been to shown to be clearly implicated in the development of DR, it affirms the importance of glycemic control in patients with DR.

Acquired resistance to cisplatin treatment is a caveat when treating patients with non-small cell lung cancer (NSCLC) and malignant pleural mesothelioma (MPM). Ceramide increases in response to chemotherapy, leading to proliferation arrest and apoptosis. However, a tumour stress activation of glucosylceramide synthase (GCS) follows to eliminate ceramide by formation of glycosphingolipids (GSLs) such as globotriaosylceramide (Gb3), the functional receptor of verotoxin-1. Ceramide elimination enhances cell proliferation and apoptosis blockade, thus stimulating tumor progression. GSLs transactivate multidrug resistance 1/P-glycoprotein (MDR1) and multidrug resistance-associated protein 1 (MRP1) expression which further prevents ceramide accumulation and stimulates drug efflux. We investigated the expression of Gb3, MDR1 and MRP1 in NSCLC and MPM cells with acquired cisplatin resistance, and if GCS activity or MDR1 pump inhibitors would reduce their expression and reverse cisplatin-resi...

The aim of this study was to determine the association of vascular endothelial growth factor (VEGF) content in 302 consecutive node-negative breast cancer (NNBC) patients treated with only locoregional radiotherapy to relapse free- (RFS) and overall survival (OS). VEGF content in tumour cytosols was measured by an enzymatic immunoassay for the major isoform VEGF165. The median age was 56 years, the median follow-up time 56 months. A wide range (0.01-144.79 pg microg(-1) DNA) of VEGF content was found (median 1.92). Significant associations were found between VEGF and oestrogen receptor (ER) content, progesterone receptor (PR) and tumour size (P = 0.005). Univariate analysis displayed significant reduced RFS and OS for patients with higher VEGF content (P = 0.0113 and P = 0.0075 respectively). A total of 43 recurrences have been found (ten local relapses within the breast, five in the axillary or supraclavicular lymph nodes and 28 distant metastasis). There was no significant correla...

A single injection of alloxan1, or alloxan-like derivatives of uric acid2,3, kills the insulin-producing islet beta-cells and causes diabetes mellitus in animals. This effect is probably mediated by a sequence of redox reactions involving the production of superoxide anion radicals in or near the beta-cells4-8. Superoxide anions may also arise in inflammation9-15, and islet inflammation often accompanies the outbreak of