hTERT-immortalized prostate epithelial and stromal-derived cells: an authentic in vitro model for differentiation and carcinogenesis

Prostate cancer is the most commonly diagnosed type of cancer in men, and there is no available cure for patients with advanced disease. In vitro model systems are urgently required to permit the study of human prostate cell differentiation and malignant transformation. Unfortunately, human prostate cells are particularly difficult to convert into continuously growing cultures. We report here the successful immortalization without viral oncogenes of prostate epithelial cells and, for the first time, prostate stromal cells. These cells exhibit a significant pattern of authentic prostate-specific features. In particular, the epithelial cell culture is able to differentiate into glandular buds that closely resemble the structures formed by primary prostate epithelial cells. The stromal cells have typical characteristics of prostate smooth muscle cells. These immortalized cultures may serve as a unique experimental platform to permit several research directions, including the study of cell-cell interactions in an authentic prostate microenvironment, prostate cell differentiation, and most significantly, the complex multistep process leading to prostate cell transformation.     

Late influenza vaccination is associated with reduced effectiveness

BACKGROUND: Extensive research has been carried out to quantify the efficacy and immunologic responses to influenza immunization, however, only little was reported on whether the timing of vaccine administration affects its effectiveness. The study aims were to compare post-immunization hospitalization and mortality rates among high-risk patients who were vaccinated against influenza in different periods of autumn. METHODS: Data for the current population-based historical prospective study were obtained from a large health organization in Israel insuring 1,600,000 members. Study population (n = 68,166) included high-risk patients aged 55 and above, who were immunized against influenza between October and November 2003. RESULTS: Although at baseline, individuals vaccinated in late November (12-25/11/2003) were significantly younger and had lower burden of illness compared to those vaccinated in early October (1-13/10/2003), they had higher hospitalization rates and longer hospital stay during the following winter (December to March). They also had an increased risk for all-cause mortality (RR = 1.78; 95%CI: 1.13-2.80). No such differences were observed during the following summer (April-August). CONCLUSIONS: In countries where influenza generally peaks between December and early March, vaccines administered after mid-November might be less beneficial.     

Caregiving stressors and psychological distress among veteran resident and immigrant family caregivers in Israel

The study compared caregiving stressors and psychological distress between Israeli veteran resident and immigrant family caregivers. It examined whether psychosocial variables (appraisal of caregiving, mastery, social support and coping) mediate the differences in psychological distress between these two groups. A total of 213 veteran resident and 206 immigrant (from the former Soviet Union) caregivers of chronically ill elderly were recruited from health services. The comparisons between the two groups were examined separately for spouse and adult child caregivers. The immigrant spouse and adult child caregivers reported significantly higher levels of caregiving stressors than veteran resident caregivers, but psychological distress was significantly higher only among the immigrant adult child caregivers. In multivariate analyses, the difference in psychological distress disappeared when caregiving stressors and mediating psychosocial variables were included in the regression models. Different caregiving stressors and psychosocial variables were associated with psychological distress among the spouses and among the adult child caregivers. The findings suggest that the caregiving stressors and psychosocial variables explain differences in psychological health outcomes between veteran resident and immigrant caregivers. Social work interventions should address these factors among caregivers, take into account the relationship to the care recipient, be culturally adapted to the immigrant caregivers, and target immigrant adult child caregivers in particular.     

Oncogenic transformation of normal enterocytes by overexpression of cyclin D1

Cyclin D1 plays an important role in the multi-step process of gastrointestinal tumorigenesis. We hypothesize that normal enterocytes over-expressing Cyclin D1 will demonstrate a transformed phenotype. The nontumorigenic intestinal epithelial cell line, IEC-18, was transfected with the vector pMV7-CCND1, encoding Cyclin D1. Three clones, with cyclin D1 levels similar to those seen in colon cancer cell lines, were further evaluated in comparison to the vector control cells. They proliferated faster and demonstrated anchorage-independent growth in soft agar, higher saturation density, and higher plating efficiency. When injected into nude mice, tumors were generated after 6–8 weeks. On the other hand these cells were more sensitive to induction of apoptosis. There was no change in the level of -catenin protein. In conclusion, Cyclin D1 can act as an oncogene in vitro and in vivo, when produced in immortalized normal intestinal epithelial cells. This model may be useful for understanding the role and interrelationships of Cyclin D1 in colorectal tumorigenesis.     

Retinal voltage-dependent anion channel: characterization and cellular localization

PURPOSE: To characterize and localize retinal voltage-dependent anion channel (VDAC) and to understand its possible contribution to mitochondrial function and dysfunction. METHODS: VDAC was characterized by a method involving purification from isolated mitochondria and reconstitution into a planar lipid bilayer (PLB). The permeability transition pore (PTP) was monitored by Ca(2+) accumulation in isolated mitochondria and swelling of mitochondria. Localization was studied by immunocytochemistry and in situ hybridization. RESULTS: Retinal VDACs exhibited the electrophysiological fingerprint of the VDAC superfamily. It had a maximal chord conductance of 3.7 +/- 0.1 nanosiemens (nS) in 1 M NaCl, and a voltage-dependent conductance that was highest at transmembrane potential close to zero. It was modulated by glutamate, which decreased the channel's open probability, and by La(3+) and ruthenium amine binuclear complex (Ru360), which closed the channel. Energized and freshly prepared retinal mitochondria accumulated Ca(2+) that is inhibited by La(3+) ruthenium red and Ru360. Subsequent to Ca(2+) accumulation, mitochondria released the accumulated Ca(2+), probably through activation of the PTP. Ru360 inhibited Ca(2+) release and mitochondrial swelling. VDAC was present in mitochondria of all retinal cell types: photoreceptor, bipolar, horizontal, amacrine, and ganglion cells. Most cells primarily expressed VDAC-1, but they also expressed VDAC-2 and -3. CONCLUSIONS: These results suggest that VDAC is involved in PTP activity and/or regulation and thus is an important player in retinal degeneration associated with PTP-mediated mitochondrial dysfunction.     

Myokine levels after resistance exercise in young adults with Prader–Willi syndrome (PWS)

Individuals with PWS require marked caloric restriction and daily exercise to prevent morbid obesity. Lower energy expenditure, hypotonia, decreased muscle mass, and cognitive impairment make exercise challenging for this population. Exercise guidelines include resistance training as an important component. Myokine responses to resistance exercise may mediate beneficial metabolic effects. We aimed to determine if young PWS adults can perform a resistance exercise program and to measure myokine responses in PWS versus age‐ and BMI‐matched controls. Each group included 11 participants (7M/4F). Ages and BMI for PWS and controls were 30.7 ± 4.6 versus 30.1 ± 4.3 years and 28.3 ± 4.3 versus 28.2 ± 4.2 kg/m², respectively. Glucose, creatine kinase (CK), lactate, and myokines were measured before, after, 30, and 60 min after completing eight resistance exercises. Myokines were assayed using a multiplex myokine panel (Merck Millipore). CK was lower in PWS versus controls (62 ± 16 vs.322 ± 100 U/L, p < .04). Peak lactate was 3.7 ± 0.7 in PWS versus 7.3 ± 0.7 mmol/Lin controls (p < .001). The increase in interleukin‐6 was similar in PWS and controls (41 ± 16% and 35 ± 10%, respectively). Pre‐ and post‐exercise levels of the six myokines assayed showed no consistent differences between the PWS and control participants. PWS young adults are capable of performing resistance/strength‐building exercise. The lower CK and peak lactate levels in PWS may reflect decreased muscle mass in this population. Further studies are needed to determine optimal exercise regimens and assess the role of myokines incontributing to the metabolic phenotype of PWS.