Biomedical subjects

R Henriksson

Publications and source records attributed to R Henriksson.

At least 37 records · Page 2Linked to original sources

PubMed2001

Bumetanide annihilation of amphotericin B-induced apoptosis and cytotoxicity is due to its effect on cellular K+ flux.

The antifungal antibiotic amphotericin B causes considerable toxic effects during clinical therapy. We have shown previously that amphotericin B-induced cytotoxicity and apoptosis were eradicated by the Na+, K+, 2Cl- cotransport inhibitor bumetanide. To elucidate the role of K+ flux and the activity of Na+, K+ ATPase and Na+, K+, 2Cl- cotransport in apoptosis and cytotoxicity induced by amphotericin B alone and combined with bumetanide, we quantified the influx and efflux of K+ of mesothelioma cells (P31) using the K+ analogue 86Rb+ with ouabain (100 micromol/L) as the K+ influx probe. To determine the susceptibility of Candida albicans to amphotericin B when combined with bumetanide we used a plate diffusion method. Amphotericin B or bumetanide alone significantly stimulated 86Rb+ efflux during the first 15 min. However, when added simultaneously, the cellular 86Rb+ efflux was markedly decreased. Amphotericin B (3 mg/L) had no effect on immediate (15 min) total 86Rb+ influx. When bumetanide (100 micromol/L) was added, the total 86Rb+ influx was markedly reduced due to inhibition of augmented Na+, K+, 2Cl- cotransport and low Na+, K+ ATPase activity. Bumetanide did not affect the susceptibility of C. albicans to amphotericin B, which suggests that bumetanide or related drugs could be used in antifungal therapy to increase amphotericin B effectiveness without increasing its adverse effects. We suggest that bumetanide hampering of amphotericin B-induced cytotoxicity and apoptosis could be due to an immediate reduction of cellular K+ efflux as well as disordered K+ influx.

Amphotericin B↗

PubMed2000

Response in shape and size of individual p31 cancer cells to cisplatin and ouabain: a computerized image analysis of cell halo characteristics during continuous perfusion.

BACKGROUND: Volume regulation is essential for cellular functions, including cell death, such as apoptosis. Flow cytometry is standard for nonadherent cells, such as blood cells. Our aim was to explore image analysis methods to study adherent cancer cells of a solid tumor. METHODS: P31 mesothelioma cells were perifused (40 min) and studied by phase-contrast microscopy. A noise reduction of the cell contour was tested to more accurately yield the cell shape factor (SF). The optical halo around the cell was analyzed for information about membrane blebbing. RESULTS: The projected cell area (PCA) slowly increased under control perfusion, the halo outside more than the halo inside. Cisplatin (apoptosis) caused an immediate increase in the PCA-halo outside (5.9 +/- 1.2 %, P < 0.01, 1-5 min) and the SF indicated decreased roundness (P < 0.05). The SF-halo inside became more irregular than the outside, which was different from the control cells. The morphology reflected instant blebbing, and the cell bodies showed fragmentation after about 20 min. Ouabain resulted in only small changes in PCA and SF, significantly different from both control and cisplatin conditions. CONCLUSIONS: Image analysis (PCA and SF) on perifused adherent cancer cells may serve as a tool to follow the sensitivity of cancer chemotherapy and to study cell death patterns.

Cell Size↗

PubMed2000

Pronounced substance P innervation in irradiation-induced enteropathy--a study on human colon.

The immunohistochemical expression of various neuropeptides, including substance P (SP), and the substance P receptor (SPR), was examined in irradiation-induced enteropathy in man. Samples from irradiated and non-irradiated patients operated on for rectal carcinoma were examined. The samples were from the sigmoid and corresponded macroscopically to non-cancerous sigmoid colon. There was a marked atrophy, ulcerations and inflammatory reactions in the irradiation-influenced mucosa. In this mucosa, there was a very pronounced innervation of varicose nerve fibers showing SP-like immunoreactivity (LI). The degree of SP-LI in the ganglionic cells of the submucous plexus was increased as compared to non-irradiated patients. There were only few or no nerve fibers showing immunoreaction for other neuropeptides examined (CGRP, enkephalin, NPY) in the irradiation-influenced mucosa. A marked SPR immunoreaction was detected in cells in the lamina propria which were interpreted as representing polymorphonuclear leukocytes. The marked expression of SP in the irradiation-damaged mucosa and the presence of SPR immunoreactive leukocytes suggest that SP is highly involved in the inflammatory reactions that occur in response to radiotherapy. The observations also suggest that SP, but not NPY, CGRP and enkephalin, has an important role in the reorganisation processes that take place in the mucosa in irradiation-induced enteropathy.

Calcitonin Gene-Related Peptide↗

PubMed2000

Effects of tobacco smoke on tumor growth and radiation response of dunning R3327 prostate adenocarcinoma in rats.

BACKGROUND: The influence of tobacco smoke has been investigated on the growth rate and histology of prostate cancer, both in untreated tumors and in those subjected to fractionated irradiation. METHODS: Twenty-five rats were implanted bilaterally with Dunning R3327 tumor fragments at 10 weeks of age. Approximately 3 months later, they were randomly allocated to two groups, one of which was exposed to tobacco smoke for an hour each day, 5 days a week. Three weeks later the groups were further subdivided into two groups which acted as controls or were subjected to 5 daily doses of 6 Gy. The tumors were measured weekly to construct growth curves. At a fixed time, 9 weeks or 20 weeks later, the animals were sacrificed and the tumors were removed for histological evaluation of the tissue composition. Sections from each tumor were scored in a morphometric analysis of the fraction of the area of tumor that was occupied by (epithelial) tumor cells, by stroma, or by luminal spaces. In addition, the density of mast cells was assessed in adjacent sections stained with toluidine blue. RESULTS: Smoking caused only minor changes in the growth rates of both the control and the irradiated tumors. At the cellular level, smoking caused a small but significant increase in the fraction of tumor cells relative to controls. Irradiation also caused a small but significant decrease in tumor cell fraction compared to controls, even after 20 weeks of regrowth. This difference was reduced in the smoking and irradiation group. The main difference observed was in the mast cell numbers. Smoking caused a 4-fold increase in mast-cell density. Irradiation caused an even greater increase (25-fold). The combination of smoking and irradiation resulted in an intermediate increase (10-fold). CONCLUSIONS: Long-term smoke exposure can slightly alter the growth rate and morphology of Dunning R3327 rat prostatic adenocarcinoma, but our study does not show a negative effect on the outcome of radiation treatment of this tumor model. We have also demonstrated a highly elevated number of mast cells in the irradiated group, and have shown that smoke exposure significantly depressed the radiation-induced enhancement of the number of mast cells.

Adenocarcinoma↗

PubMed2000

p53 and vascular-endothelial-growth-factor (VEGF) expression predicts outcome in 833 patients with primary breast carcinoma.

The angiogenic factor vascular endothelial growth factor (VEGF) predicts outcome in primary breast carcinoma. Alteration of the p53 gene causes down-regulation of the expression of thrombospondin-1, a natural inhibitor of angiogenesis. This study was conducted to investigate the association between mutant p53 protein and VEGF expression, and the prognostic value of these factors. VEGF165 and p53 protein were measured in tumour cytosols by enzyme immunoassays. Recurrence-free survival (RFS) and overall survival (OS) were estimated in 833 consecutive patients, 485 node-negative (NNBC) and 348 node-positive (NPBC) with primary invasive breast cancer. A significant association was found between mutant p53 protein and VEGF expression. Univariate analysis showed both p53 and VEGF to be significant predictors of survival. Similar correlation was seen when p53 was combined with VEGF. Univariate analysis of NNBC showed significant prognostic value of p53 for OS, also when combined with VEGF expression; for NPBC, significant reductions in RFS and OS were seen for p53-positive patients, and these findings were enhanced when combined with VEGF, also in the sub-group receiving adjuvant endocrine treatment. Multivariate analysis showed both p53 and VEGF as independent predictors of OS in all groups. When the 2 factors were combined, an increased relative risk of 2.7 was seen for OS in the group with both p53 positivity and high VEGF content, as compared with 1.7 in the group with one risk factor. The results suggest an association between loss of wt-p53 and increased VEGF expression, indicating that angiogenic activity may depend, at least partly, on altered p53-protein function. Combination of these 2 biological markers appears to give additional predictive information of survival. A high-risk group of patients was associated with p53 positivity and higher VEGF content.

Breast Neoplasms↗

PubMed2000

Primary brain tumours as second primary: a novel association between meningioma and colorectal cancer.

In a previous study, a decreased risk for first degree relatives of patients with astrocytoma has been observed for breast and colorectal cancer. The aim of this study was to examine the associations between breast and colorectal cancer as first primary cancer and the risk of developing astrocytoma and meningioma as a second primary cancer. Two cohorts were constructed, one from all cases with breast cancer (1,036,466 person-years) and one from all cases of colorectal cancer (572,422 person-years) in Sweden during the period 1958-1994. The risk of developing astrocytoma and meningioma after breast or colorectal cancer was calculated. A significant increased risk for developing meningioma was seen after colorectal cancer, standardized incidence ratio (SIR) 1.60 confidence interval (CI; 1.32-1.94) and after breast cancer, SIR 1. 57 CI (1.36-1.81). The previously observed decreased risk for astrocytoma could not be verified in this study. A novel association between meningioma and colorectal cancer, particularly in females, was observed, which justifies further studies to evaluate common aetiological factors.

Aged↗

PubMed2000

Amphotericin B-induced apoptosis and cytotoxicity is prevented by the Na+, K+, 2Cl(-)-cotransport blocker bumetanide.

Amphotericin B is the most commonly used antifungal drug although it exhibits poor effectiveness and considerable toxicity during treatment. It acts as a ionophore inducing cellular potassium efflux. The efflux of potassium, which is necessary for cell shrinkage during apoptosis, is counteracted by increased inward pumping of potassium ions. Modulation of potassium pump activity could therefore interact with programmed cell death depending on the nature of the disruption of cellular potassium homeostasis and subsequently affect the cytotoxicity of various drugs. We explored the role of apoptosis in amphotericin B-induced cytotoxicity in a mesothelioma cell line (P31) and investigated the role of K+ influx inhibitors of Na+, K+, ATPase and Na+, K+, 2Cl(-)-cotransport in these processes. Clone formation was used to determine the cytotoxicity of amphotericin B, ouabain (Na+, K+, ATPase blocker), and bumetanide (Na+, K+, 2Cl(-)-cotransport blocker), alone or in combination. Apoptosis was estimated by quantifying free nucleosomes. Amphotericin B (3.2 micromol/L, 3 mg/L) per se reduced the percentage of surviving clones to 64% and increased the number of nucleosomes by 31% compared to untreated control. When ouabain (100 micromol/L) was added to amphotericin B a less than additive effect on clone formation was seen but no reduction of nucleosomes was noted. Bumetanide (100 micromol/L) per se was not cytotoxic but increased cellular nucleosome expression. Bumetanide eradicated amphotericin B-induced reduction of formed clones and generated nucleosomes. In conclusion, the induction of apoptosis seems to be of significant importance in amphotericin B-induced cytotoxicity. Amphotericin B-induced cytotoxicity and apoptosis was eradicated by the Na+, K+, 2Cl(-)-cotransport inhibitor bumetanide. The changes of cellular K+ fluxes induced by bumetanide combined with amphotericin B needs further elucidation. Bumetanide could possibly be used in antifungal therapy to increase amphotericin B effectiveness doses without increasing its adverse effects.

Amphotericin B↗

PubMed2000

How was life after treatment of a malignant brain tumour?

The malignant glioma is a severe disease with an unfavourable prognosis. Aside from a few case studies, the knowledge of the victimised patients' lives from diagnosis to death is mainly restricted to studies assessing functional status and rating quality of life by means of questionnaires. From a clinician's perspective this knowledge is not sufficient. By introducing the concepts 'time of everyday life' and 'time of disease', the purpose of this paper is to supplement with descriptive knowledge of clinical value. Twenty-eight patients with malignant gliomas and their spouses were followed during the course of the disease by repeated interviews. The time after treatment was then judged as representing, 'time of everyday life' or 'time of disease'. Life after treatment turned out to be quite varied. To slightly more than a third of the patients', life-continuity was lost, experiencing only 'time of disease'. Among the others who were judged to experience 'time of everyday life' and who were of working age, nearly two-thirds were able to resume work or studies on a part-time basis. In the total sample, the mean 'time of everyday life' turned out to be nearly equal to 'time of disease', 6.1 and 5.4 months, respectively. The findings are illustrated by case descriptions and the conceptualisation of time into 'everyday life' and 'disease' is proposed as meriting further study.

Adult↗

PubMed2000

Estramustine-binding protein in malignant glioma in rat.

Estramustine is a chemotherapeutic drug, used in the treatment of prostatic carcinoma. In the prostate, it binds specifically to a 46 kDa glycoprotein called estramustine-binding protein (EMBP), which consists of three polypeptide components; C1, C2, and C3, each coded for by a specific gene. Expression of EMBP and binding of estramustine has also been detected in malignant glioma in both rats and humans. Elevated levels of this protein in astrocytoma have proved to correlate with poor prognosis. In the present work, expression of all three polypeptide components of EMBP was confirmed in an orthotopic rat glioma model with nested reverse transcriptase PCR and Western blot (molecular weights of 8, 10, and 12 kDa). Specific binding of estramustine with a Kd of 40 for male and 50 for female rats, and a total number of binding sites of 0.7 and 0.4 pmol/mg proteins for male and female rats respectively, was demonstrated with Scatchard plot analysis. These binding characteristics are similar to those of prostatic EMBP. Further studies to elucidate how EMBP expression affects the effect of estramustine treatment, and its putative prognostic value is of special clinical interest. The confirmation of BMBP expression in BT4C rat glioma demonstrates its suitability as a model system for such studies.

Animals↗

PubMed2000

Interleukin-2 and histamine in combination inhibit tumour growth and angiogenesis in malignant glioma.

Biotherapy including interleukin-2 (IL-2) treatment seems to be more effective outside the central nervous system when compared to the effects obtained when the same tumour is located intracerebrally. Recently published studies suggest that reduced activity of NK cells in tumour tissue can be increased by histamine. The present study was designed to determine whether IL-2 and histamine, alone or in combination, can induce anti-tumour effects in an orthotopic rat glioma model. One group of rats was treated with histamine alone (4 mg kg(-1)s.c. as daily injections from day 6 after intracranial tumour implantation), another group with IL-2 alone as a continuous subcutaneous infusion and a third group with both histamine and IL-2. The animals were sacrificed at day 24 after tumour implantation. IL-2 and histamine in combination significantly reduced tumour growth. The microvessel density was significantly reduced, an effect mainly affecting the small vessels. No obvious alteration in the pattern of VEGF mRNA expression was evident and no significant changes in apoptosis were observed. Neither IL-2 nor histamine alone caused any detectable effects on tumour growth. Histamine caused an early and pronounced decline in tumour blood flow compared to normal brain. The results indicate that the novel combination of IL-2 and histamine can be of value in reducing intracerebral tumour growth and, thus, it might be of interest to re-evaluate the therapeutic potential of biotherapy in malignant glioma.

Animals↗

PubMed2000

Analysis of VIP and CGRP plasma levels after radiotherapy for treatment of metastasis from prostatic carcinoma.

It has previously been shown that radiotherapy leads to an increased level of neuropeptides in various organs. In the study we report here, we examined whether the plasma levels of two neuropeptides, vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP), are influenced by radiotherapy. Blood was collected at four time intervals after radiotherapy; 1-12 days after treatment for skeletal metastasis from prostatic carcinoma. The VIP- and CGRP-plasma levels, as analyzed by radioimmunoassay, were not statistically different between the different time points analyzed.

Bone Neoplasms↗

PubMed2000

Correlation of vascular endothelial growth factor content with recurrences, survival, and first relapse site in primary node-positive breast carcinoma after adjuvant treatment.

PURPOSE: To determine the predictive value of vascular endothelial growth factor (VEGF) for relapse-free survival (RFS) and overall survival (OS) in primary node-positive breast cancer (NPBC) after adjuvant endocrine treatment or adjuvant chemotherapy. MATERIALS AND METHODS: VEGF was quantitatively measured in tumor cytosols from 362 consecutive patients with primary NPBC using an enzyme immunoassay for human VEGF(165). Adjuvant treatment was given to all patients, either as endocrine therapy (n = 250) or chemotherapy (n = 112). The median follow-up time was 56 months. RESULTS: Univariate analysis showed VEGF to be a significant predictor of RFS (P =.0289) and OS (P =.0004) in the total patient population and in patients who received adjuvant endocrine treatment (RFS, P =.0238; OS, P =.0121). In the group of patients who received adjuvant chemotherapy, no significant difference was seen in RFS, but a difference was seen in OS (P =.0235). Patients with bone recurrences tended to have lower VEGF expression (median, 2.17 pg/microg DNA) than patients with visceral metastasis (4.41 pg/microg), brain metastasis (8.29 pg/microg), or soft tissue recurrences (3.16 pg/microg). Multivariate analysis showed nodal status (P =.0004), estrogen receptor (ER) status (P <.0001), and tumor size (P =.0085) to be independent predictors of RFS. VEGF was found to be an independent predictor of OS (P =.0170; relative risk [RR] = 1.82), as were ER (P <.0001; RR = 5.19) and nodal status (P =.0002; RR = 2.58). For patients receiving adjuvant endocrine treatment, multivariate analysis showed VEGF content to be an independent predictor of OS (P =.0420; RR = 1.90) but not of RFS. CONCLUSION: The results suggest that VEGF(165) content in tumor cytosols is a predictor of RFS and OS in primary NPBC. VEGF content might also predict outcome after adjuvant endocrine treatment, but further studies in a prospective setting with homologous treatments are required.

Aged↗

PubMed1999

Increase in doxorubicin cytotoxicity by carvedilol inhibition of P-glycoprotein activity.

Acquired resistance to chemotherapy is a major problem during cancer treatment. One mechanism for drug resistance is overexpression of the MDR1 (multidrug resistance) gene encoding for the transmembrane efflux pump, P-glycoprotein (P-gp). The calcium channel blocker verapamil has been shown to reverse cellular drug resistance by inhibiting P-gp drug efflux. This study evaluated whether the new antihypertensive drug carvedilol influenced doxorubicin (Dox) cytotoxicity and P-gp activity in a P-gp-expressing cell line compared to a non-expressing subline. Verapamil (10 micromol/L), and even more markedly, carvedilol (10 micromol/L) increased cellular uptake of P-gp-transported calcein of a P-gp-expressing breast cancer cell line (Hs578T-Dox). In the subline (Hs578T) not expressing P-gp, no effects of carvedilol or verapamil on calcein uptake were seen. Carvedilol and verapamil (10 micromol/L) reduced the LD50 (dose which results in the death of half the number of cells) of the Hs578T-Dox subline from 200 mg/L to approx. 10 mg/L Dox, whereas the LD50 of the Hs578T subline was only marginally affected. Carvedilol (10 micromol/L) reduced P-gp activity approximately twice as effectively as verapamil at an equimolar concentration. Carvedilol did not affect pyrogallol cytotoxicity and pyrogallol was without effect on calcein accumulation of the Hs578T-Dox cell line, indicating the lack of antioxidative properties affecting P-gp activity and associated toxicity of the drug. The results suggest that carvedilol has the clinical potential to reverse tumour MDR involving the efflux protein P-gp.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1999

[Modified cost-benefit analysis takes equity into consideration. Treatment of brain tumors is more cost-effective than hip replacement].

As health care resources are held to be insufficient to permit free choice of available treatment options, prioritizing is necessary. A precondition of careful prioritizing is comprehensive knowledge of the consequences, both for the patient and the community, of adopting each of the available options in a given case. A tool used in setting priorities is cost-benefit analysis, based on the utilitarian principle of health maximisation. However, it is evident from findings in recent studies that equity is widely considered a factor which ought to be included in the analysis. The article presents a method for correcting the variable, quality-adjusted life years (QALY), by introducing an equity factor, yielding a new variable, equity-adjusted QALY (EQALY). Use of the method is illustrated by comparison of the cost-effectiveness of two procedures, hip replacement and the treatment of malignant glioma, and showing how priority ranking of the two procedures is reversed if the EQALY variable is used instead of QALY.

Adult↗

PubMed1999

Familial aggregation of astrocytoma in northern Sweden: an epidemiological cohort study.

This population-based cohort study investigated the occurrence of familial astrocytoma among first-degree relatives of patients with astrocytoma diagnosed between 1985 and 1993 in the northern region of Sweden. The 432 cases received a questionnaire. They were asked to provide names and cancer diagnoses of first-degree relatives. Of the 297 answering, a cohort was constructed of their 1,890 first-degree relatives (FDR). A significantly increased risk [standardized incidence ratio, SIR = 2.12, 95% confidence interval (CI) = 1.18-3.49] was shown for developing primary brain tumors (PBT). In 4.7% (14/297) of the families, a PBT was found. Interestingly, the increased risk was for astrocytoma only (SIR = 3.12, 95% CI 1.42-5.92), and not for other PBT (SIR 0.90, 95% CI 0.18-2.64). When the cohort was divided according to the median age of proband, most of the increased risk was restricted to the younger cohort (SIR = 4.71, 95% CI 1.52-10.99). Surprisingly, a significantly decreased risk for breast cancer and colon cancer was shown. The finding that the increased risk is restricted to astrocytoma only is a novel one. This study implies that familial aggregation of astrocytoma exists; the familial clustering occurs in a small fraction of astrocytoma, and might be explained by inherited factors.

Adult↗

PubMed1999

[Surprising ability to handle bad news. A study of how cancer patients create hope].

The article discusses findings in a study where malignant glioma patients were serially interviewed to determine how they constructed new perceptions of reality when confronted with the diagnosis. Although most of the patients were aware that the tumour posed a grave threat, they were also able to find refuge and hope by using various cognitive strategies. The process, that draws on various resources (the body, supportive relationships, cognitive schemata, and information processing), is discussed in relation to adjacent psychoanalytic theory, and is regarded as an expression of the 'intermediate area' of mental life, which is proposed as theoretical point of reference in discussing How to tell cancer patients.

Adaptation, Psychological↗

PubMed1999

Estramustine-binding protein in meningioma.

The presence of estramustine-binding protein has been suggested to positively correlate with the effect of the cytotoxic drug estramustine, a combination of estradiol and nornitrogen mustard used in the treatment of prostatic carcinoma. This study demonstrates expression of estramustine-binding protein in a series of meningioma using different ligand-based and immunological techniques. Scatchard plot analysis showed specific binding sites for [3H]lestramustine in meningioma tissue with a dissociation constant of 22-26 nM. Immunohistochemistry revealed an immunoreactivity in meningioma comparable to that demonstrated in prostatic carcinoma. The mean concentration (n = 6) of estramustine-binding protein in meningioma, as determined by radioimmunoassay was 159 ng/g tissue (range 18-274 ng/g). Moreover, partial characterization using size exclusion chromatography of [3H]estramustine-labeled tumor extracts and Western blot analysis of immunoprecipitated samples indicated that the structure of the estramustine-binding protein in meningioma is similar to that in rat prostate, with three polypeptide components of 10, 14, and 16 kDa, as compared to 8, 10-11, and 12 kDa in rat prostate. In conclusion, the novel observation of estramustine-binding protein and specific binding of estramustine in meningioma justify further evaluation regarding the role of estramustine-binding protein in the growth behavior of meningioma and the potential for estramustine and similar hormone-related drugs in the treatment of relapsing meningioma.

Blotting, Western↗

PubMed1999

Serotoninergic modulation of cell volume response to estramustine: an image-analysis study on perifused individual glioma cells.

A technique of microscopy with computerised detection of early morphological changes during continuous perifusion was used to monitor the geometry changes of cultured glioma cells (MG-251) when exposed to 40 mg/L estramustine phosphate (EMP) alone or in combination with granisetron (0.1 mumol/L), ondansetron (0.1 mumol/L), or serotonin (1 mumol/L). When the cells were exposed to EMP, cell volume measured as projected cell area (PCA) rapidly increased. Serotonin and ondansetron, but not granisetron, prevented the acute EMP response (PCA). Serotonin, but none of the 5-HT3 receptor antagonists, protected against the cytotoxicity of EMP to the glioma cells as measured by a fluorometric microculture assay. Our results demonstrate hitherto unknown differences between selective 5-HT3 receptor antagonist on the cellular response to EMP and shows the necessity to study the receptor antagonists from viewpoint of interference with the antitumour drug effects on malignant cells. The perifusion technique could be used to study the effects of serotoninergic agonists and antagonists on cell volume regulation of cells exposed to anticancer drugs.

Cell Size↗