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1.
Br J Dermatol ; 164(1): 62-7, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20846310

ABSTRACT

BACKGROUND: Captopril, an angiotensin I-converting enzyme inhibitor, is a commonly prescribed antihypertensive drug. Its cutaneous side-effects include pemphigus vulgaris acantholysis and bullous pemphigoid-like cell-matrix detachment. This medication also triggers apoptosis in human keratinocytes. Calcitriol, the hormonally active vitamin D metabolite, protects keratinocytes from programmed cell death induced by various noxious stimuli. OBJECTIVES: To examine if calcitriol protects proliferating keratinocytes from the damage inflicted by captopril. METHODS: Autonomously proliferating HaCaT keratinocytes, used as a model for basal layer keratinocytes, were exposed to captopril. Cell detachment was examined visually by light microscopy. Cytotoxicity was assessed by Hoechst 33342 staining and lactate dehydrogenase release. Apoptotic death was assessed by monitoring caspase 3-like activity. RESULTS: Cells exposed to captopril detached and became round. This process was accompanied by programmed cell death. From time-dependent monitoring of cell detachment and apoptosis, and examination of pan-caspase inhibitor effects on cell detachment we concluded that cell death is the consequence of cell detachment from the culture plate and not vice versa. Pretreatment with calcitriol significantly attenuated these events. The effects of calcitriol were already evident at 1 nmol L(-1) concentration of the hormone. CONCLUSIONS: The results of this study show that calcitriol protects keratinocytes from captopril-induced cell detachment and apoptosis.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors , Antihypertensive Agents/antagonists & inhibitors , Apoptosis/drug effects , Captopril/antagonists & inhibitors , Keratinocytes/drug effects , Vitamin D/pharmacology , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Antihypertensive Agents/pharmacology , Apoptosis/physiology , Captopril/pharmacology , Caspase 3/analysis , Humans , Keratinocytes/cytology , Keratinocytes/enzymology , L-Lactate Dehydrogenase/analysis
2.
J Cell Physiol ; 222(3): 729-37, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20020446

ABSTRACT

MMP-9, a member of the matrix metalloproteinase family that degrades collagen IV and processes chemokines and cytokines, participates in epidermal remodeling in response to stress and injury. Limited activity of MMP-9 is essential while excessive activity is deleterious to the healing process. Tumor necrosis factor (TNFalpha), a key mediator of cutaneous inflammation, is a powerful inducer of MMP-9. Calcitriol, the hormonally active vitamin D metabolite, and its analogs are known to attenuate epidermal inflammation. We aimed to examine the modulation of MMP-9 by calcitriol in TNFalpha-treated keratinocytes. The immortalized HaCaT keratinocytes were treated with TNFalpha in the absence of exogenous growth factors or active ingredients. MMP-9 production was quantified by gelatin zymography and real-time RT-PCR. Activation of signaling cascades was assessed by western blot analysis and DNA-binding activity of transcription factors was determined by EMSA. Exposure to TNFalpha markedly increased the protein and mRNA levels of MMP-9, while pretreatment with calcitriol dose dependently reduced this effect. Employing specific inhibitors we established that the induction of MMP-9 by TNFalpha was dependent on the activity of the epidermal growth factor receptor, c-Jun-N-terminal kinase (JNK), NFkappaB and extracellular signal-regulated kinase-1/2. The effect of calcitriol was associated with inhibition of JNK activation and reduction of DNA-binding activities of the transcription factors activator protein-1 (AP-1) and NFkappaB following treatment with TNFalpha. By down-regulating MMP-9 levels active vitamin D derivatives may attenuate deleterious effects due to excessive TNFalpha-induced proteolytic activity associated with cutaneous inflammation.


Subject(s)
Calcitriol/metabolism , Keratinocytes/enzymology , Matrix Metalloproteinase 9/metabolism , Tumor Necrosis Factor-alpha/metabolism , Blotting, Western , Cell Line , Electrophoretic Mobility Shift Assay , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/metabolism , Humans , JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , JNK Mitogen-Activated Protein Kinases/metabolism , Keratinocytes/drug effects , Matrix Metalloproteinase 9/genetics , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/antagonists & inhibitors , Mitogen-Activated Protein Kinase 3/metabolism , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Protein Kinase Inhibitors/pharmacology , RNA, Messenger/metabolism , Recombinant Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Time Factors , Transcription Factor AP-1/metabolism , Up-Regulation , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/metabolism
3.
Br J Dermatol ; 160(1): 151-61, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18717671

ABSTRACT

BACKGROUND: Radiotherapy can induce severe skin responses that may limit the clinically acceptable radiation dose. The responses include erythema, dry and moist desquamation, erosions and dermal-epidermal blister formation. These effects reflect injury to, and reproductive failure of, epidermal cells and may also be due to dysregulation of the tissue remodelling process caused by excessive proteolytic activity. Calcitriol, the hormonally active vitamin D metabolite, protects keratinocytes from programmed cell death induced by various noxious stimuli. OBJECTIVE: To examine whether calcitriol protects proliferating keratinocytes from the damage inflicted by ionizing radiation under conditions similar to those employed during radiotherapy. METHODS: Autonomously proliferating HaCaT keratinocytes, used as a model for basal layer keratinocytes, were irradiated using a linear accelerator. Cell death was monitored by vital staining, executioner caspase activation, lactic dehydrogenase release and colony formation assay. Induction of matrix metalloproteinase-9 was assessed by gelatinase activity assay and mRNA determination. Levels of specific proteins were determined by immunoblotting. RESULTS: Treatment with calcitriol inhibited both caspase-dependent and -independent programmed cell death occurring within 48 h of irradiation and increased the colony formation capacity of irradiated cells. These effects may be attributable to inhibition of the c-Jun NH(2)-terminal kinase cascade and to upregulation of the truncated antiapoptotic isoform of p63. Treatment with the hormone also attenuated radiation-induced increase in matrix metalloproteinase-9 protein and mRNA levels. CONCLUSIONS: The results of this study suggest that active vitamin D derivatives may attenuate cell death and excessive proteolytic activity in the epidermis due to exposure to ionizing radiation in the course of radiotherapy.


Subject(s)
Cell Proliferation/radiation effects , Keratinocytes , Radiation Injuries/prevention & control , Vitamin D/pharmacology , Vitamins/pharmacology , Caspase 3/metabolism , Cell Death , Cells, Cultured , Epithelial Cells/metabolism , Epithelial Cells/radiation effects , Humans , In Vitro Techniques , Keratinocytes/drug effects , Keratinocytes/metabolism , Keratinocytes/radiation effects , Matrix Metalloproteinase 9/metabolism , Matrix Metalloproteinase 9/radiation effects , RNA, Messenger , Radiation, Ionizing , Reverse Transcriptase Polymerase Chain Reaction , Vitamin D/metabolism
4.
Apoptosis ; 11(4): 519-34, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16532377

ABSTRACT

The epidermis is confronted with multiple environmental and pathophysiological stresses. This study shows that TNFalpha, oxidative stress, hyperosmotic and heat shock induced both caspase-dependent and independent cell death in human HaCaT keratinocytes. The hormonal form of vitamin D, 1,25(OH)2D3, which is an autocrine hormone in the epidermis, protected the cells from all the examined stresses and pathways leading to cell death. We aimed to define the signaling pathways that determine the life-death balance of stressed keratinocytes and participate in their protection by 1,25(OH)2D3. As assessed by employing specific inhibitors, the survival pathways mediated by the EGF receptor, ERK, PI-3K or Src kinase, or basal transcriptional activity are important for unstressed cell survival. However, only the EGF receptor, PI-3K and the Src kinase pathways mediate the survival of stressed cells in a stimulus-specific manner. Inhibition of the p38 and/or the JNK death pathways reduced caspase activation induced by oxidative stress, hyperosmotic shock and TNFalpha. The protective effect of 1,25(OH)2D3 was not mediated by the examined survival pathways. 1,25(OH)2D3 inhibited the stress-induced activation of p38 and JNK. Since mimicking this effect by pharmacological inhibition resulted in the attenuation of caspase activation, we infer that these pathways are involved in keratinocyte protection by 1,25(OH)2D3.


Subject(s)
Apoptosis , Calcitriol/pharmacology , Keratinocytes/enzymology , Signal Transduction , Apoptosis/drug effects , Caspases/metabolism , Cell Line , Cell Proliferation , Cell Survival , Enzyme Inhibitors/pharmacology , Humans , JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , JNK Mitogen-Activated Protein Kinases/physiology , Keratinocytes/cytology , Keratinocytes/drug effects , MAP Kinase Signaling System/drug effects , Osmotic Pressure , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/physiology
5.
Colorectal Dis ; 5(3): 228-32, 2003 May.
Article in English | MEDLINE | ID: mdl-12780883

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate functional outcome and quality of life (QOL) in patients undergoing proctocolectomy ileal pouch anal anastomosis (IPAA), to assess the correlation between functional outcome and QOL, and to identify factors influencing functional outcome and QOL in these patients. BACKGROUND: IPAA is now considered the procedure of choice for ulcerative colitis. Functional outcome and QOL are important factors in evaluating operative outcome. METHODS: All patients with UC who had undergone IPAA at our institute during the period 1990-2001 were included. QOL and functional outcome were evaluated by mailed questionnaires. QOL was scored using the Short Form 36 (SF-36). Global Assessment of Function Scale was used to evaluate functional outcome. RESULTS: Data were obtained in 77 of 99 patients (78%), with the median age of 38 years. Median follow up time was 4.25 years. The QOL in patients after pelvic pouch procedure was excellent, with scores equal to published norms for the Israeli general population in most scales. Functional outcome and QOL scores correlated strongly (r > 0.5; P < 0.0001) in all dimensions. Older age was associated with lower scores in both functional outcome and QOL scales (P < 0.0001). CONCLUSIONS: This study demonstrates a strong association between functional outcome and QOL in patients after IPAA. These patients, however, have a QOL that is comparable with the general population. Age at time of surgery strongly influences both functional outcome and QOL. This finding has to be taken into consideration in pre-operative counseling.


Subject(s)
Anal Canal/physiopathology , Anal Canal/surgery , Anastomosis, Surgical/adverse effects , Colitis, Ulcerative/physiopathology , Colitis, Ulcerative/surgery , Colonic Pouches/adverse effects , Outcome Assessment, Health Care , Postoperative Complications , Proctocolectomy, Restorative/adverse effects , Quality of Life , Recovery of Function/physiology , Adolescent , Adult , Aged , Child , Female , Follow-Up Studies , Humans , Male , Middle Aged , Risk Factors , Time Factors
7.
Ann N Y Acad Sci ; 1010: 437-40, 2003 Dec.
Article in English | MEDLINE | ID: mdl-15033766

ABSTRACT

Calcitriol, the hormonal form of vitamin D, enhanced TNF-induced cytotoxicity in MCF-7 breast cancer cells. It increased the induction of caspase-3-like activity and TNF-induced caspase-independent cytotoxicity in the presence of a pan-caspase inhibitor. The antioxidants N-acetylcysteine, glutathione, lipoic acid, and ascorbic acid markedly reduced the effect of the hormone on TNF-induced caspase activation, attesting to the involvement of reactive oxygen species (ROS) in the cross-talk between the hormone and the cytokine. Calcitriol augmented the drop in mitochondrial membrane potential induced by TNF as assessed by the fluorescent probe JC-1. We postulate that the interaction of TNF and calcitriol on the level of the mitochondria underlies the enhancement of TNF-induced, ROS-mediated caspase-dependent and -independent cell death.


Subject(s)
Apoptosis/drug effects , Breast Neoplasms/pathology , Calcitriol/pharmacology , Caspases/metabolism , Tumor Necrosis Factor-alpha/toxicity , Antioxidants/pharmacology , Cell Death , Cell Line, Tumor , Cell Survival/drug effects , Enzyme Activation , Female , Humans , Reactive Oxygen Species/metabolism
8.
Dis Colon Rectum ; 45(10): 1283-8, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12394423

ABSTRACT

PURPOSE: This study was designed to evaluate the pregnancies, method of delivery, and functional results of females with chronic ulcerative colitis who have an ileal pouch-anal anastomosis. METHODS: A mailed questionnaire was sent to all females with an ileal pouch-anal anastomosis for chronic ulcerative colitis. Information on the pregnancy, method of delivery, and outcome was collected. Those females who had a successful pregnancy and delivery were contacted by telephone to clarify results and determine pouch functional results. Other clinical information was obtained from the Mount Sinai Hospital Inflammatory Bowel Disease database. RESULTS: Thirty-eight subjects had 67 pregnancies. Of these, 29 subjects had 49 deliveries. There were 25 vaginal deliveries and 24 cesarean sections. There were two pouch-related complications during the pregnancies and four pouch-related complications postpartum. All were treated nonoperatively. Stool frequency and day and night incontinence were increased during pregnancy in most subjects, but after delivery, prepregnancy function was restored in 24 (83 percent) of them. Five subjects (17 percent) had some degree of permanent deterioration in pouch function. Of these, three had vaginal deliveries, and two had cesarean sections. Multiple births and birth weight were not found to adversely affect subsequent pouch function. CONCLUSION: Pregnancy is safe in females with ileal pouch-anal anastomosis. Functional results are altered almost exclusively during the third trimester, but pouch function promptly returns to prepregnancy status in most females. A small proportion of females have long-term disturbances in function, but these are not related to the method of delivery. Thus, the method of delivery should be dictated by obstetric considerations.


Subject(s)
Colitis, Ulcerative/surgery , Colonic Pouches , Delivery, Obstetric , Pregnancy Outcome , Adult , Defecation , Fecal Incontinence , Female , Humans , Middle Aged , Pregnancy , Retrospective Studies
9.
J Endocrinol ; 173(3): 525-32, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12065242

ABSTRACT

In addition to its known effects on keratinocyte proliferation and differentiation, the hormonal form of vitamin D, 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), has been shown to protect keratinocytes from UV- and chemotherapy-induced damage. Epidermal keratinocytes contain both the machinery needed to produce 1,25(OH)(2)D(3) and vitamin D receptors. The activation of the stress-activated protein kinases (SAPKs), such as c-Jun N-terminal kinase (JNK) and p38, is an early cellular response to stress signals and an important determinant of cell fate. This study examines whether modulation of these SAPKs is associated with the effects of 1,25(OH)(2)D(3) on keratinocytes under stress. HaCaT keratinocytes were exposed to heat shock, hyperosmotic concentrations of sorbitol, the epidermal growth factor receptor tyrosine kinase inhibitor AG1487, the pro-inflammatory cytokine tumor necrosis factor alpha, and H(2)O(2). These stresses activated both SAPKs. Pretreatment with 1,25(OH)(2)D(3) inhibited the activation of JNK by all stresses and the activation of p38 by heat shock, AG1478 and tumor necrosis factor alpha. Under the same conditions, treatment with 1,25(OH)(2)D(3) protected HaCaT keratinocytes from cytotoxicity induced by exposure to H(2)O(2) and hyperosmotic shock. The effect of 1,25(OH)(2)D(3) was dose-dependent, already apparent at nanomolar concentrations, and time-dependent, maximal after a 24-h pre-incubation. We suggest that inhibition of SAPK activation may account for some of the well-documented protective effects of 1,25(OH)(2)D(3) on epidermal cells during exposure to UV or chemotherapy and may also be related to the anti-inflammatory actions of the hormone in skin.


Subject(s)
Calcitriol/pharmacology , Enzyme Activation/drug effects , Keratinocytes/drug effects , Oxidative Stress , Protein Kinases/metabolism , Cell Line , Depression, Chemical , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , ErbB Receptors/antagonists & inhibitors , Hot Temperature , Humans , Hydrogen Peroxide/pharmacology , JNK Mitogen-Activated Protein Kinases , Keratinocytes/enzymology , Mitogen-Activated Protein Kinases/metabolism , Osmotic Pressure , Quinazolines , Sorbitol/pharmacology , Time Factors , Tumor Necrosis Factor-alpha/pharmacology , Tyrphostins/pharmacology , p38 Mitogen-Activated Protein Kinases
11.
Lasers Surg Med ; 29(3): 265-73, 2001.
Article in English | MEDLINE | ID: mdl-11573230

ABSTRACT

BACKGROUND AND OBJECTIVE: Laser soldering of tissues is based on the application of a biological solder on the approximated edges of a cut. Our goal was to use laser soldering for sealing cuts in skin under temperature feedback control and compare the results with ones obtained using standard sutures. STUDY DESIGN/MATERIALS AND METHODS: Albumin solder was applied onto the approximated edges of cuts created in rat skin. A fiberoptic system was used to deliver the radiation of a CO(2) laser, to heat a spot near the cut edges, and to control the temperature. Laser soldering was carried out, spot by spot, where the temperature at each spot was kept at 65-70 degrees C for 10 sec. RESULTS: The tensile strength of laser-soldered cuts was measured after 3-28 days postoperatively and was found comparable to that of sutured cuts. Histopathological studies showed no thermal damage and less inflammatory reaction than that caused by standard sutures (P = 0.04). CONCLUSIONS: Temperature controlled laser soldering of cuts in rat skin gave strong bonding. The cosmetic and histological results were very good, in comparison to those of standard sutures.


Subject(s)
Fiber Optic Technology , Laser Therapy/instrumentation , Laser Therapy/methods , Suture Techniques/instrumentation , Temperature , Wounds and Injuries/surgery , Albumins , Analysis of Variance , Animals , Biocompatible Materials , Dermis/pathology , Dermis/radiation effects , Dermis/surgery , Epidermis/pathology , Epidermis/radiation effects , Epidermis/surgery , Fibroblasts/pathology , Fibroblasts/radiation effects , Granulation Tissue/pathology , Granulation Tissue/radiation effects , Granulation Tissue/surgery , Male , Radiometry , Rats , Rats, Sprague-Dawley , Sutures , Tensile Strength/radiation effects , Wounds and Injuries/pathology
12.
Otolaryngol Head Neck Surg ; 125(3): 157-60, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11555747

ABSTRACT

OBJECTIVE: This study evaluates the effectiveness and safety of fiberoptic carbon dioxide (CO2) laser welding for graft closure of tympanic membrane perforations in an animal model. STUDY DESIGN AND SETTING: Tympanic membrane perforation was surgically induced in 11 eardrums of 7 given pigs. A lumbar facial graft was placed over the wound, and albumin drops served as a biologic solder. CO2 laser energy, transmitted through silver halide infrared transmitting fibers, was used for "spot-welding" along the circumference of the graft. The welded sites were evaluated by using a surgical microscope as well as by evaluating the sites histologically. RESULTS: Healing started 3 to 4 days after surgery and was completed within 3 weeks with the formation of a neotympanum. Some inflammation with granulation tissue was noted in 5 eardrums. CONCLUSIONS AND SIGNIFICANCE: These preliminary results indicate that CO2 laser tympanoplasty with a fiberoptic delivery system may be a promising new technique for the clinical setting.


Subject(s)
Laser Therapy , Models, Animal , Myringoplasty/methods , Tympanic Membrane Perforation/surgery , Animals , Carbon Dioxide , Feasibility Studies , Fiber Optic Technology , Guinea Pigs , Laser Therapy/methods , Wound Healing
13.
Cancer Res ; 61(4): 1439-44, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11245448

ABSTRACT

The anticancer activity of the hormonal form of vitamin D, 1,25-dihydroxyvitamin D [1,25(OH)2D], is associated with inhibition of cell cycle progression, induction of differentiation, and apoptosis. In addition, 1,25(OH)2D3 augments the activity of anticancer agents that induce excessive reactive oxygen species generation in their target cells. This study aimed to find out whether 1,25(OH)2D3, acting as a single agent, is a prooxidant in cancer cells. The ratio between oxidized and reduced glulathione and the oxidation-dependent inactivation of glyceraldehyde-3phosphate dehydrogenase (GAPDH) are considered independent markers of cellular reactive oxygen species homeostasis and redox state. Treatment of MCF-7 breast cancer cells with 1,25(OH)2D3 (10-100 nM for 24-48 h) brought about a maximal increase of 41+/-13% (mean +/- SE) in the oxidized/reduced glutathione ratio without affecting total glutathione levels. The in situ activity of glutathione peroxidase and catalase were not affected by 1,25(OH)2D3, as assessed by the rate of H2O2 degradation by MCF-7 cell cultures. Neither did treatment with 1,25(OH)2D3 affect the levels of glutathione reductase or glutathione S-transferase as assayed in cell extracts. The hormone did not affect overall glutathione consumption and efflux as reflected in the rate of decline of total cellular glutathione after inhibition of its synthesis by buthionine sulfoximine. The extent of reversible oxidation-dependent inactivation of GAPDH in situ was determined by comparing the enzyme activity before and after reduction of cell extracts with DTT. The oxidized fraction was 0.13+/-0.02 of total GAPDH in control cultures and increased by 56+/-5.3% after treatment with 1,25(OH)2D3, which did not affect the total reduced enzyme activity. Treatment with 1,25(OH)2D3 resulted in a approximately 40% increase in glucose-6-phosphate dehydrogenase, the rate-limiting enzyme in the generation of NADPH. This enzyme is induced in response to various modes of oxidative challenge in mammalian cells. Taken together, these findings indicate that 1,25(OH)2D3 causes an increase in the overall cellular redox potential that could translate into modulation of redox-sensitive enzymes and transcription factors that regulate cell cycle progression, differentiation, and apoptosis.


Subject(s)
Breast Neoplasms/metabolism , Calcitriol/pharmacology , Oxidants/pharmacology , Antimetabolites/pharmacology , Buthionine Sulfoximine/pharmacology , Glutathione/metabolism , Glutathione Disulfide/metabolism , Glutathione Peroxidase/metabolism , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Homeostasis/drug effects , Humans , Oxidation-Reduction/drug effects , Reactive Oxygen Species/metabolism , Tumor Cells, Cultured
14.
J Steroid Biochem Mol Biol ; 73(3-4): 105-12, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10925209

ABSTRACT

It was previously shown that 1,25-dihydroxyvitamin D(3) (1, 25(OH)(2)D(3)) enhances the cytotoxic activity of tumor necrosis factor alpha (TNFalpha), doxorubicin and menadione. A feature shared by these anticancer agents is the involvement of reactive oxygen species (ROS) in their action. In this work we found that 1, 25(OH)(2)D(3) acted synergistically with interleukin 1 beta (IL-1beta) or interleukin 6 (IL-6) to inhibit the proliferation of MCF-7 breast cancer cells. The extent of the synergism was maximal at 1 nM, a concentration at which 1,25(OH)(2)D(3), acting singly, only marginally reduced the cell number. The thiol antioxidant, N-acetylcysteine (NAC) abolished the synergism between IL-1beta or IL-6 and 1,25(OH)(2)D(3), but had only a small protective effect when the cytokines acted alone. NAC and reduced glutathione (GSH) protected MCF-7 cells from cytotoxicity induced both by TNFalpha alone and by TNFalpha and 1,25(OH)(2)D(3). A two-day exposure to TNFalpha caused a 27.7+/-3.1% (mean +/- SEM) reduction in GSH content. This effect increased to 46.4+/-5.5% by co-treatment with 1, 25(OH)(2)D(3) which did not affect GSH levels on it own. We conclude that 1,25(OH)(2)D(3) can act synergistically with anticancer cytokines present in the tumor milieu and that ROS plays a mediatory role in this interaction.


Subject(s)
Antineoplastic Agents/pharmacology , Calcitriol/pharmacology , Interleukin-1/pharmacology , Interleukin-6/pharmacology , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Acetylcysteine/pharmacology , Cell Division/drug effects , Drug Synergism , Glutathione/pharmacology , Humans
15.
Eur J Cancer ; 36(9): 1120-4, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10854945

ABSTRACT

A single germ line mutation in BRCA1, (185delAG) is detected in a substantial portion of Jewish Israeli patients with ovarian cancer. Whether disease phenotypes differ in BRCA1 mutation carriers and sporadic cases is presently a subject for debate. To gain insight into this issue, we analysed tumours from 65 Jewish women with ovarian cancer, 29 (45%) were 185delAG BRCA1 mutation carriers, and 36 (55%) were non-carriers of any of the predominant Jewish mutations in BRCA1 or BRCA2 (sporadic). In 19/29 mutation carriers (66%) diagnosis was made prior to age 60 years, compared with 14/36 (39%) of the non-carriers (P=0.03; Yates corrected P=0.06). Low malignant potential ('borderline') tumours were detected less frequently among carriers (2/29; 7%) than non-carriers (9/36; 25%) (P=0.03; one tail P=0.05). Immunohistochemical analysis in invasive carcinoma (n=54) showed that 17/27 carriers (63%) and 18/27 non-carriers (67%) had positive nuclear staining with a p53 antibody. In 4/27 carriers (15%) and 3/25 non-carriers (12%), 25% or more of the tumour cells stained positive for Ki-67, an insignificant difference. Results were not altered by including borderline tumours (n=11) in these analyses. We conclude that the rate of TP53 inactivation and proliferative index in ovarian cancer, are similar for 185delAG BRCA1 mutation carriers and sporadic cases.


Subject(s)
Jews/genetics , Neoplasm Proteins/genetics , Ovarian Neoplasms/genetics , Transcription Factors/genetics , Aged , BRCA2 Protein , Female , Genes, BRCA1 , Germ-Line Mutation/genetics , Heterozygote , Humans , Immunohistochemistry , Ki-67 Antigen/analysis , Middle Aged , Pedigree , Prognosis , Tumor Suppressor Protein p53/metabolism
16.
J Urol ; 161(5): 1662-5, 1999 May.
Article in English | MEDLINE | ID: mdl-10210435

ABSTRACT

PURPOSE: Laser tissue welding has potential advantages over conventional suture closure of surgical wounds. It is a noncontact technique that introduces no foreign body and limits the possibility of infections and complications. The closure could be immediately watertight and the procedure may be less traumatic, faster and easier. In spite of these positives laser welding has not yet been approved for wide use. The problem in the clinical implementation of this technique arises from the difficulty in defining the conditions under which a highly reliable weld is formed. We have assumed that the successful welding of tissues depends on the ability to monitor and control the surface temperature during the procedure, thereby avoiding underheating or overheating. The purpose of this work was to develop a laser system for reliable welding of urinary tract tissues under good temperature control. MATERIALS AND METHODS: We have developed a "smart" laser system that is capable of a dual role: transmitting CO2 laser power for tissue heating, and noncontact (radiometric) temperature monitoring and control. Bladder opening (cystotomy) was performed in 38 rats. Thirty-three animals underwent laser welding. In 5 rats (control group) the bladder wound was closed with one layer of continuous 6-0 dexon sutures. Reliable welding was obtained when the surface temperature was kept at 71 + 5C. Quality of weld was controlled immediately after operation. The rats were sacrificed on days 2, 10 and 30 for histological study. RESULTS: Bladder closure using the laser welding system was successful in 31/33 (94%) animals. Histological examination revealed an excellent welding and healing of the tissue. CONCLUSIONS: Efficiency of laser welding of urinary bladder in rats was confirmed by high survival rate and quality of scar that was demonstrated by clinical and histological examinations. In the future, optimal laser welding conditions will be studied in larger animals, using CO2 lasers and other lasers, with deeper radiation penetration into tissues.


Subject(s)
Hot Temperature , Laser Therapy , Suture Techniques , Urinary Bladder/surgery , Animals , Evaluation Studies as Topic , Female , Rats , Rats, Sprague-Dawley
17.
Endocrinology ; 140(2): 713-21, 1999 Feb.
Article in English | MEDLINE | ID: mdl-9927298

ABSTRACT

Topical treatment of normal skin with 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] or its synthetic analogs results in enhanced keratinocyte proliferation. Autocrine growth factors belonging to the epidermal growth factor (EGF) family play a major role in controlling keratinocyte proliferation. 1,25-(OH)2D3 enhanced the autonomous proliferation of HaCaT human keratinocytes in the absence of exogenous growth factors. Autonomous and 1,25-(OH)2D3-stimulated proliferations were inhibited by a specific inhibitor of EGF receptor (EGFR) tyrosine kinase, an EGFR-neutralizing antibody, heparin, the heparin antagonist hexadimethrine, and the proteoglycan sulfation inhibitor chlorate. These results indicate the involvement of proteoglycan-dependent EGFR ligands. The initial events in EGFR (i.e. ErbB1) mitogenic signal transduction are dimer formation with another ErbB protein and tyrosine cross-phosphorylation. By immunoprecipitation followed by Western blotting we showed that ErbB1/ErbB3 heterodimers are the major mitogenic signaling entity in 1,25-(OH)2D3-stimulated cells. 1,25-(OH)2D3 did not affect the levels of the proteoglycan-dependent EGFR ligands amphiregulin and heparin-binding EGF nor the synthesis of proteoglycans, as assessed by 35S labeling and ion exchange chromatography. 1,25-(OH)2D3 caused a marked increase in the cellular contents of ErbB1, ErbB2, and ErbB3 proteins. The increase in ErbB proteins that mediates signal transduction by EGFR ligands can account for the stimulatory effect of 1,25-(OH)2D3 on autonomous keratinocyte proliferation.


Subject(s)
Autocrine Communication/physiology , Calcitriol/pharmacology , ErbB Receptors/physiology , Keratinocytes/cytology , Autocrine Communication/drug effects , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Cell Division/drug effects , Cell Division/physiology , Cell Line , Enzyme Activation/drug effects , ErbB Receptors/metabolism , Growth Substances/physiology , Humans , Keratinocytes/metabolism , Ligands , Phosphorylation , Proteoglycans/metabolism , Proteoglycans/physiology , Receptors, Growth Factor/metabolism , Sulfates/metabolism
18.
Cancer Res ; 59(4): 862-7, 1999 Feb 15.
Article in English | MEDLINE | ID: mdl-10029076

ABSTRACT

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the hormonal form of vitamin D, has anticancer activity in vivo and in vitro. Doxorubicin exerts its cytotoxic effect on tumor cells mainly by two mechanisms: (a) generation of reactive oxygen species (ROS); and (b) inhibition of topoisomerase II. We studied the combined cytotoxic action of 1,25(OH)2D3 and doxorubicin on MCF-7 breast cancer cells. Pretreatement with 1,25(OH)2D3 resulted in enhanced cytotoxicity of doxorubicin. The average enhancing effect after a 72-h pretreatment with 1,25(OH)2D3 (10 nM) followed by a 24-h treatment with 1 microg/ml doxorubicin was 74+/-9% (mean +/- SE). Under these experimental conditions, 1,25(OH)2D3 on its own did not affect cell number or viability. 1,25(OH)2D3 also enhanced the cytotoxic activity of another ROS generating quinone, menadione, but did not affect cytotoxicity induced by the topoisomerase inhibitor etoposide. The antioxidant N-acetylcysteine slightly reduced the cytotoxic activity of doxorubicin but had a marked protective effect against the combined action of 1,25(OH)2D3 and doxorubicin. These results indicate that ROS are involved in the interaction between 1,25(OH)2D3 and doxorubicin. 1,25(OH)2D3 also increased doxorubicin cytotoxicity in primary cultures of rat cardiomyocytes. Treatment of MCF-7 cells with 1,25(OH)2D3 alone markedly reduced the activity, protein, and mRNA levels of the cytoplasmic antioxidant enzyme Cu/Zn superoxide dismutase, which indicated that the hormone inhibits its biosynthesis. This reduction in the antioxidant capacity of the cells could account for the synergistic interaction between 1,25(OH)2D3 and doxorubicin and may also suggest increased efficacy of 1,25(OH)2D3 or its analogues in combination with other ROS-generating anticancer therapeutic modalities.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Calcitriol/pharmacology , Doxorubicin/pharmacology , Breast Neoplasms/metabolism , Dose-Response Relationship, Drug , Drug Synergism , Etoposide/pharmacology , Female , Humans , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolism , Topoisomerase II Inhibitors , Tumor Cells, Cultured , Vitamin K/pharmacology
19.
J Clin Gastroenterol ; 28(1): 81-2, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9916677

ABSTRACT

We present case reports of 2 patients who were admitted to our ward for complications of Morgagni hernias. Both patients were elderly. Morgagni hernia is a rare condition. Its unique and late presentation are presented and discussed.


Subject(s)
Hernia, Diaphragmatic/complications , Aged , Aged, 80 and over , Female , Hernia, Diaphragmatic/surgery , Hernias, Diaphragmatic, Congenital , Humans , Male , Pneumonia, Aspiration/etiology , Respiratory Insufficiency/etiology
20.
Harefuah ; 136(5): 366-8, 418, 1999 Mar 01.
Article in Hebrew | MEDLINE | ID: mdl-10914241

ABSTRACT

We describe a 26-year-old woman with thrombocytopenia discovered during gestation. On admission for evaluation of abdominal pain, torsion of an ectopic spleen was found. The spleen was removed and the thrombocytopenia resolved.


Subject(s)
Choristoma/diagnosis , Pregnancy Complications/diagnosis , Spleen , Stomach Diseases/surgery , Thrombocytopenia/diagnosis , Abdominal Pain , Adult , Choristoma/diagnostic imaging , Choristoma/surgery , Female , Humans , Pregnancy , Pregnancy Complications, Hematologic/diagnosis , Radiography , Splenectomy , Stomach Diseases/diagnostic imaging , Torsion Abnormality
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