[Obesity as a risk factor for prostate cancer: role for adipocytokines and involvement of tyrosine kinase pathway]

PURPOSE

Obesity is considered to be a risk factor for prostate cancer. Mitogenic actions of leptin, an adipocyte-derived hormone in a variety of cancer cell types have been identified. We have investigated the proliferative effects of leptin on human prostate cancer cells and assessed the role of tyrosine kinase signalling in mediating these actions.

MATERIALS AND METHODS

Two human androgen-resistant prostate cancer cell lines and one androgen-sensitive human prostate adenocarcinoma cell line were treated with leptin (5-100 ng / mL) for up to 48 hours. Under serum-free conditions, cell proliferation was measured using an enzyme-linked colorimetric assay. Furthermore, phosphorylation of a downstream component of MAPK (ERK1 / 2) was detected by Western blotting and a specific inhibitor of MAPK (PD98059; 40 microM) was used to evaluate the role of this signalling pathway.

RESULTS

Leptin dose-dependently increased the cell number in both androgen-resistant cell lines after 24 h and 48 h of incubation (percent of control: DU145 = 194.6 +/- 5.9 %, PC-3 = 177.9 +/- 6.8 %; 100 ng / mL leptin; 48 h; p < 0.001). Conversely, leptin's proliferative effect on the androgen-sensitive cell line was less pronounced (percent of control: LNCaP = 112.3 +/- 6.1 %; 100 ng / mL leptin; 48 h). Leptin also caused dose-dependent ERK1 / 2 phosphorylation in both androgen-resistant cell lines. In addition, pre-treatment with PD98059 inhibited these responses and attenuated leptin's mitogenic action.

CONCLUSIONS

Data from this in vitro study suggest an association between obesity-associated hyperleptinemia and an increased risk for prostate cancer. Further investigations are necessary to clarify whether these data have clinical relevance regarding the use as a prognostic marker for predicting the timing of the occurrence of androgen resistency.

Organ recipients suffering from undifferentiated neuroendocrine small-cell carcinoma of donor origin: a case report

BACKGROUND

Transmission of donor-derived cancer by organ transplantation is rare, but the risk has been increasing due to the aging donor pool. Undifferentiated neuroendocrine small-cell carcinoma is an aggressive tumor with the tendency to spread. Herein we have demonstrated different approaches to treat organ recipients with transmitted tumors.

METHODS AND RESULTS

Grafts were retrieved from a decreased donor without any history of previous diseases. Autopsy was not performed after donation. The recipient of the liver graft presented with suspected nodules on routine abdominal ultrasound. After computed tomography (CT) scan, biopsy confirmed the diagnosis of a small-cell carcinoma. Donor origin was unequivocally identified by DNA fingerprinting. Despite chemotherapy the patient died 7 months after orthotopic liver transplantation (OLT). All involved transplantation centers were informed immediately following diagnosis. The male kidney recipient underwent detailed diagnostic work-up to exclude tumor transmission. One year after transplantation, liver metastases caused by a histologically proven small-cell carcinoma from the same donor were apparent. Chemotherapy was immediately started and the graft was removed. Despite continued treatment the tumor progressed and the patient died after repeated intestinal complications. The pathological examination of the explanted second kidney graft did not show any tumor infiltration.

CONCLUSION

Therapeutic regimens in recipients suffering from donor-derived carcinoma differ depending on the transplanted organ. Graft removal of non-life-sustaining organs and discontinuation of immunosuppressive medication should result in complete tumor rejection. Minimizing the risk of tumor transmission, a CT scan might be advisable in donors of more advanced age.

Utility of a simplified molecular classification of tumors for predicting survival of patients with invasive ductal breast carcinoma

BACKGROUND

In a recent report it was shown that molecular subgroups of early (pT1) breast tumors belonging exclusively to the most common histological variant, ductal-infiltrating carcinoma, showed significantly different clinical and biological features.

OBJECTIVE

To test in a series of patients with ductal-infiltrating carcinoma encompassing all stages of the disease if the above-mentioned biological differences already detected at the earliest stage are ultimately reflected in survival differences.

PATIENTS AND METHODS

All patients with ductal infiltrating carcinoma operated upon at Hospital de Móstoles, Madrid, Spain, between 1997 and 2002 were included into the study, to allow for at least five years of follow-up for survivors. Of 242 studied patients, according to the International Federation of Gynecology and Obstetrics (FIGO) classification, 37.6% were in stage I, 47.2% in stage II, 11.0% in stage III, and 4.2% in stage IV. According to the simplified molecular classification of Carey et al., 116 tumors (47.9%) expressed estrogen receptors, and did not express c-erb-B2 (Luminal A), 67 (27.7%) coexpressed hormone receptors (either estrogen receptors, progesterone receptors or both) and c-erb-B2 (Luminal B), 33 (13.3%) expressed c-erb-B2 in the absence of hormone receptors (HER-2), and 26 (10.7%) neither expressed hormone receptors, nor c-erb-B2 (triple-negative, basal).

RESULTS

In a univariate model, both disease-free survival and overall survival of the patients were significantly associated with stage (p=0.0003; p<0.0001), histological grade (p<0.0001; p<0.0001), lymphatic vascular space invasion (p=0005; p=0.0044), menopausal status (p=0.04; p=0.034) and molecular subgrouping (p=0.037: p=0.01). In a multivariate model, only stage (p=0.013), grade (p<0.0001), and menopausal status (p=0.007) retained their prognostic power for predicting disease-free survival, and just stage (p<0.0001) and grade (p<0.0001) for predicting overall survival. The molecular classification of the tumors almost reached statistical significance for predicting overall survival (p=0.06).

Phase transitions in solid solution series bismutocolumbite – stibiocolumbite (Bi-Sb)(Nb0.79Ta0.21)O4

The crystal structure of bismutocolumbite, Bi(Nb0.79Ta0.21)O4 with orthorhombic (sp. gr. Pnna) stibio-tantalite structure type at ambient conditions has been de-termined at 2.59 and 9.56 GPa, and 23oC. Crystal data and results of structure refinement using powder X-ray diffrac-tion and Rietveld analysis for Bi-rich stibiocolumbite, (Sb0.52Bi0.48)(Nb0.71Ta0.29)O4, are reported. At the pressure ~2.9 GPa bismutocolumbite exhibits phase transition which is accompanied by the change of its symmetry: sp. gr. Pnna is replaced by the sp. gr. Pn21 a. This kind of transformation is anticipated at ambient pressure in bismutocolumbite- stibiocolumbite solid solution series in the compounds with Sb/(Bi+Sb) ratio higher than 0.52 which characterises the studied crystals of stibiotantalite. Similarly with scheelite-like BiVO4, in bismutocolumbite the reduction of the unit cell volume under HP is mainly a result of Bi-O polyhedral compression, which is accompanied by a rearrangement of (Nb,Ta)O6 octahedra within octahedral sheets parallel to (010). (Nb,Ta)O6 octahedra remain rigid with smaller change in size at high pressure.

Powder Rietveld refinement of armstrongite, CaZr[Si6O15]·3H2O

Crystal data and results of structure refinement using powder X-ray diffraction and Rietveld analysis for armstrongite, CaZr[Si6O15]·3H2O, are reported. Experimental data were collected using MoKα1 radiation over the range 2° - 51.98° 2θ. Armstrongite is monoclinic (space group C2, Z = 4), with a = 14.018(1) Å, b = 14.133(1) Å, c = 7.840(1) Å, β = 109.40(1)°. The crystal structure, reported by Kashaev and Sapozhnikov (1978) has been refined by Rietveld analysis, resulting in Rwp = 2.75. The structure is based on a heterogeneous octahedra-tetrahedra framework (ZrSi6O15) built by corrugated silicate sheets connected by ZrO6 octahedra. The seven-fold Ca polyhedron contains 2 H2O molecules. Two new sites for H2O molecules on the 2-fold axis in the voids of the zeolite like framework allowed to achieve the complete correspondence between chemical and structural data.

Polymorph stability and phase transitions of trigonal Al1- x Ga x PO4 mixed crystals

Single crystals of Al1- x Ga x PO4 of various mole fractions x were grown from phosphoric acid solutions under hydrothermal conditions using the slow-heating method. In order to relate the parameters of this low-quartz structure analogue and the observed phase transitions to the respective mole fraction, the crystals were investigated by means of electron probe microanalysis, X-ray powder diffraction and differential thermal analysis. The results are discussed in terms of the segregation effects occuring during growth. The limiting geometrical parameters for the existence of the high-quartz phase are compared to the values given in the literature.

A powder diffraction study of the phase transition in LaAlO3

The structure of LaAlO3 has been investigated around the phase transition at Tc ≈ 800 K by neutron powder diffraction in vacuum and by X-ray powder diffraction under nitrogen atmosphere as well as by a very high resolution synchrotron experiment in air. The results were analysed in frame of the Landau theory using the fluctuation-dissipation theorem to relate the susceptibility to the atomic displacement parameters. The room temperature structure is a rhombohedrally distorted perovskite structure, space group R-3c , which undergoes a transition to the ideal perovskite structure, space group Pm-3m , at high temperatures. The order parameter is a rotation of the O6-octahedron described by one x(O)-parameter. This parameter and the spontaneous strain (c/a-√6), as well as the relevant atomic displacement parameter Uop 11(O) in the order parameter system, show a critical behaviour in agreement with a second order phase transition. Although the critical exponents of the order parameter and strain show the expected coupling behaviour, there is a striking difference of the transition temperature: the metric becomes cubic roughly 30 K below the proper Tc. This is related to spontaneous formation of domains imposing the average cubic symmetry via internal stresses.

Comparative effects of chlormadinone acetate and its 3alpha- and 3beta-hydroxy metabolites on progesterone, androgen and glucocorticoid receptors

AIM/METHODS

In vitro binding tests to human receptors and in vivo functional activities in animals were used to compare the effects of the progestin chlormadinone acetate (CMA) and its 3alpha- and 3beta-hydroxy metabolites (3alpha-OH-CMA and 3beta-OH-CMA) on progesterone, androgen and glucocorticoid receptors.

RESULTS

CMA, 3alpha-OH-CMA, 3beta-OH-CMA and the reference progestin R5020 bound to human progesterone receptor with Ki values of 2.5 nm, 13 nm, 6.0 nm and 4.3 nm, respectively. Binding affinities to the human androgen receptor were characterized by Ki values of 3.8 nM for CMA, 83 nM for 3alpha-OH-CMA, 20 nM for 3beta-OH-CMA and 2.9 nM for the reference androgen methyltrienolone. The Ki values for binding to the human glucocorticoid receptor were 16 nM for CMA, 69 nM for 3alpha-OH-CMA, 21 nM for 3beta-OH-CMA and 1.2 nM for the glucocorticoid dexamethasone. In the rabbit endometrial proliferation test CMA, 3alpha-OH-CMA and 3beta-OH-CMA (5 and 45 microg/kg p.o. for 5 days) had similar progestomimetic activities. CMA, 3alpha-OH-CMA and, to a lesser extent, 3beta-OH-CMA (4.64 and 21.5 mg/kg p.o. for 7 days) inhibited testosterone-stimulated growth of prostate and seminal vesicles in castrated rats showing antiandrogenic activities. Glucocorticoid properties were demonstrated for CMA and 3alpha-OH-CMA (21.5 and 100 mg/kg p.o. for 6 days) but not for 3beta-OH-CMA as reduction in thymus and adrenal gland weights in immature rats.

CONCLUSION

Binding assays at human receptors showed similarly high affinities of CMA with the progesterone and androgen receptors and a 5 times lower affinity with the glucocorticoid receptor. At all receptor types, CMA had the highest, 3alpha-OH-CMA the lowest and 3beta-OH-CMA an intermediate affinity. Animal studies revealed progestomimetic and antiandrogenic activities of CMA, 3alpha-OH-CMA and 3beta-OH-CMA and glucocorticoid activities of CMA and 3alpha-OH-CMA.

Influence of fatty acid diets on gene expression in rat mammary epithelial cells

BACKGROUND

This study examines the impact of dietary fatty acids on regulation of gene expression in mammary epithelial cells before and during puberty.

METHODS

Diets primarily consisted of n-9 monounsaturated fatty acids (olive oil), n-6 polyunsaturated fatty acids (safflower), saturated acids (butter), and the reference AIN-93G diet (soy oil). The dietary regimen mimics the repetitive nature of fatty acid exposure in Western diets. Diet-induced changes in gene expression were examined in laser capture microdissected mammary ductal epithelial cells at day of weaning and end of puberty. PCNA immunohistochemistry analysis compared proliferation rates between diets.

RESULTS

Genes differentially expressed between each test diets and the reference diet were significantly enriched by cell cycle genes. Some of these genes were involved in activation of the cell cycle pathway or the G2/M check point pathway. Although there were some differences in the level of differential expression, all diets showed qualitatively the same pattern of differential expression compared to the reference diet. Cluster analysis identified an expanded set of cell cycle as well as immunity and sterol metabolism related clusters of differentially expressed genes.

CONCLUSION

Fatty acid-enriched diets significantly upregulated proliferation above normal physiological levels during puberty. Higher cellular proliferation during puberty caused by enriched fatty acid diets poses a potential increase risk of mammary cancer in later life. The human homologs of 27 of 62 cell cycle rat genes are included in a human breast cancer cluster of 45 cell cycle genes, further emphasizing the importance of our findings in the rat model.

Impacts of Wireless Power on Medical Device Design Safety

Wireless power holds great promise for solving many power distribution problems. Medical device designers will need to understand the impact of the electromagnetic coupling used for wireless power systems to design safe electromagnetic environments and safe medical devices. One question for designers will be whether or not current standards and requirements used for testing the electromagnetic compatibility (EMC) of medical devices and human exposure go far enough to insure safe environments and safe and reliable medical devices in the presence of wireless power. Electromagnetic energy can be transferred in three ways: through induction, radio frequency waves, or resonant evanescent coupling. Nonradiative inductive coupling uses the magnetic fields created when current is passed through one coil to create a current in a second coil that is located very near the first coil. These systems usually operate in the 50 KHz to 10 MHz range. Radio frequency energy can be transferred through radiating electromagnetic waves over great distances at frequencies from the upper KHz to many GHz. Most recently, work has been done on resonant evanescent coupling which transfers power between resonant objects over a distance of a couple of meters at frequencies from 1–10 MHz. Safety and reliability of medical devices is confirmed by testing EMC emissions and susceptibility to IEC60601-1-2 and supporting standards. For example, one of the supporting standards, CISPR 11 calls for measuring the electric field of radiated emissions over 30 MHz and the magnetic field below 30 MHz at distances of 3–10 meters. Many of the effects of wireless power systems are in the near field and are not covered in the current test standards. The AAMI PC69 series of standards have some near field requirements but these standards tend to be industry specific – such as drug pumps or pacemakers. EMC immunity standards used to test EMC susceptibility barely mention magnetic immunity. The only test for magnetic fields recommends testing fields at the power frequencies of 50 and 60 Hz. There are few standards detailing safe limits for human exposure to the near field effects of wireless power as well. Historically human exposure standards have been based on time average thermal effects on tissue and not medical devices. IEEE's C95.1b has requirements for specific absorption rate limits averaged over a 6 minute period. A pulsed wireless power system could meet these requirements and be safe for exposed tissue, but if a patient has an implanted device, or is wearing an external medical device, the pulsed EM energy could affect it during the pulse. The German BGV B11 standard lists human exposure limits for electric and magnetic fields based on a time average and limits exposure based on which portion of the body is exposed. However, it is meant as a workplace standard not a medical device standard. Currently the FDA does not require meeting either of these standards. It is necessary to determine the appropriate limits and tests to ensure that medical devices safely use wireless power and continue to operate safely in the presence of wireless power.

Harnessing stakeholder perspectives to improve the care of osteoporosis after a fracture

This study used in-depth interviews and focus groups to evaluate osteoporosis care after a fracture. Patients (eligible women aged 67 who sustained a clinical fracture(s)), clinicians, and staff stated that an outreach program facilitated osteoporosis care management, but more-tailored education and support and increased participation of orthopedic specialists appear necessary.

INTRODUCTION

Osteoporosis treatment reduces fracture risk, but screening and treatment are underutilized, even after a fracture has occurred. This study evaluated key stakeholder perspectives about the care of osteoporosis after a fracture.

METHODS

Participants were from a nonprofit health maintenance organization in the United States: eligible women members aged 67 or older who sustained a clinical fracture(s) (n = 10), quality and other health care managers (n = 20), primary care providers (n = 9), and orthopedic clinicians and staff (n = 28); total n = 67. In-depth interviews and focus groups elicited participant perspectives on an outreach program to patients and clinicians and other facilitators and barriers to care. Interviews and focus group sessions were transcribed and content-analyzed.

RESULTS

Patients, clinicians, and staff stated that outreach facilitated osteoporosis care management, but important patient barriers remained. Patient knowledge gaps and fatalism were common. Providers stated that management needed to begin earlier, and longer-term patient support was necessary to address adherence. Orthopedic clinicians and staff expressed lack of confidence in their osteoporosis management but willingness to encourage treatment.

CONCLUSIONS

Although an outreach program assisted with the management of osteoporosis after a fracture, more-tailored education and support and increased participation of orthopedic specialists appear necessary to maximize osteoporosis management.

Rosiglitazone reduces angiotensin II and advanced glycation end product-dependent sustained nuclear factor-kappaB activation in cultured human proximal tubular epithelial cells

Tubular damage is a major feature in the development of diabetic nephropathy. This study investigates the effects of the thiazolidindione rosiglitazone on angiotensin II and advanced glycation end product-induced tubular activation in human proximal tubular epithelial cells IN VITRO. Angiotensin II and advanced glycation end products, both induced a dose-dependent sustained activation of the redox-sensitive transcription factor, Nuclear Factor KAPPA B (NF-kappaB). Nuclear translocation of NF-kappaB was evident already after one hour and persistent for more than four days. Co-incubation of proximal tubular epithelial cells with rosiglitazone significantly reduced angiotensin II and advanced glycation end product-mediated generation of reactive oxygen species, angiotensin II-dependent advanced glycation end product formation, NF-kappaB activation, and NF-kappaB-dependent pro inflammatory gene expression. Most importantly, rosiglitazone effects on NFkappaB activation were maximal at later time points, indicating that rosiglitazone treatment confers long lasting renoprotective effects.

[Sinonasal basaloid squamous cell carcinoma in biopsies of inverted papilloma]

Basaloid squamous cell carcinoma (BSCC) is a rare tumor representing an aggressive variant of squamous cell carcinoma (SCC) and arising from a common precursor cell. BSCC rarely originates from the sinonasal tract. We report on an 83-year-old woman with BSCC after multiple resections of an inverted papilloma (IP) of the left sinonasal tract. The tumor filled the nasal cavity completely and was infiltrating the ipsilateral frontal skull base and periorbita. Because of the tumor's expansion, the patient's age, and comorbidity, surgery was not performed, but primary radiotherapy was initiated. A possible association between sinonasal BSCC and IP, as implicated by the current case, must be further investigated. In any case, IP requires consequent endoscopic and, if necessary, radiological follow-up in order to detect recurrent disease or malignant transformation.

Bax expression in untreated breast cancer: an immunocytometric study of 255 cases

BACKGROUND

Bax is one of the main effectors of apoptosis in breast cancer. However, in contrast with the antiapoptotic protein Bcl-2, which has been extensively studied in this tumor, there are relatively few clinical studies on the biological role of Bax in breast cancer.

MATERIALS AND METHODS

The expression of the apoptosis-related Bax gene was studied in a series of 255 previously untreated breast cancers by means of immuno-flow cytometry. Additionally, and by the same method, the expression of the Bcl-2, VEGF and Nup88 genes were also studied. As variables of the study for the final statistical analysis, the histological variety of the tumors, histological and nuclear grade, the expression of hormone receptors, p53, Ki-67 or c-erb-B2, axillary node invasion, tumor size and DNA-ploidy were also included.

RESULTS

The expression of the proapoptotic Bax protein was significantly associated with the expression of Nup88 (p<0.0001), VEGF (p=0.0014) and Bcl-2 (p=0.0063), all measured by the same method. An inverse correlation with c-erb-B2 expression, which almost attained statistical significance (p=0.058) was also registered.

CONCLUSION

This study adds evidence to the little explored link between apoptosis and angiogenesis. Furthermore, it discloses a previously unreported relationship between Bax and Nup88 expression.

Dynamic active telepathology over National Health Laboratory service network, South Africa: feasibility study using Nikon Coolscope

Telepathology recently entered a new era with the introduction of digital microscopes combined with Internet technology. The microscope allows viewing real time of whole slide (macro) as well as different chosen fields in four different magnifications. Three Nikon Coolscope were installed in NHLS laboratories in Mthatha, East London and Port Elizabeth. All these microscopes are connected to NHLS server allowing real time viewing of the full slide at any time of the day using Internet browser. Viewing is possible from any PC connected to NHLS Intranet. The challenge was to be able to view slides from other than NHLS computers due to NHLS IT Department network security measures. This was solved by installing NHLS Virtual Private Network server. About 60 cases were viewed by pathologists in Cape Town (Stellenbosh University) and Pretoria (MEDUNSA). All users assessed the system as a helpful tool allowing easy access to cases needing consultation or second opinion. The quality of images was very good. Our experience with Nikon Coolscope is positive. It is an excellent tool for remote small histopathology departments lacking specialists in such areas as dermatopathology, oncology, and haematopathology. Further studies are needed especially in the scope of full utilization of the microscopes installed and impact on laboratory services.

The small variant of the apoptosis-associated X-chromosome RBM10 gene is co-expressed with caspase-3 in breast cancer

BACKGROUND

There are very few studies on the final triggers of apoptosis, the caspases, in breast cancer.

MATERIALS AND METHODS

Caspase-3 expression was studied by means of reverse transcript polymerase chain reaction (RT-PCR) in a series of 108 previously untreated patients with breast cancer. Expression levels were correlated with those obtained using the same technique of the apoptosis-associated X-chromosome genes RBMX, RBM3, RBM10 small and RBM10 large variant; Bcl-2 and Bax; the angiogenesis-associated genes VEGF and CD105 (endoglin); hMAM and Nup88. The correlation with the expression of hormone receptors, c-erb-B2, mutant p53 and Ki-67, all measured by means of immunohistochemistry, was also studied, as well as that with standard clinical parameters such as histological type, tumor size, axillary metastasis and DNA-ploidy.

RESULTS

The only statistically significant correlations observed between caspase-3 mRNA expression and the parameters tested were a direct one with both the Bax (p = 0.007) and the small variant of the X-chromosome RBM10 gene (p = 0.018), and an inverse one with the angiogenesis-associated CD105 (endoglin) gene (p = 0.044).

CONCLUSION

These results indicate that very few genes are involved in the last steps of the apoptotic cascade in breast cancer, among them one of the X-chromosome RBM family. They also support the relatively unexplored link between apoptosis and angiogenesis.