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1.
Ir Med J ; 110(7): 605, 2017 Aug 08.
Article in English | MEDLINE | ID: mdl-29341517

ABSTRACT

We describe the case of a 20-year-old rower presenting with an uncommon condition of Proliferative Myositis (PM) affecting the Latissimus Dorsi (LD). PM is a rare, benign tumour infrequently developing in the upper back. Its rapid growth and firm consistency may mistake it for sarcoma at presentation. Therefore, careful multidisciplinary work-up is crucial, and should involve appropriate radiological and histopathological investigations. Here, we propose the aetiology of LD PM to be persistent myotrauma induced by repetitive rowing motions. Symptoms and rate of progression ultimately determine the management which includes surveillance and/or conservative resection. There have been no documented cases of recurrence or malignant transformation.


Subject(s)
Cumulative Trauma Disorders/complications , Myositis/etiology , Superficial Back Muscles/injuries , Water Sports/injuries , Humans , Male , Young Adult
2.
Breast ; 30: 125-129, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27718416

ABSTRACT

BACKGROUND: The diagnosis and management of lobular neoplasia (LN) including lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH) remains controversial. Current management options after a core needle biopsy (CNB) with lobular neoplasia (LN) incorporating both ALH and LCIS include excision biopsy or careful clinical and radiologic follow up. METHODS: A retrospective analysis of the surgical database at Cork University Hospital was performed to identify all core needle biopsies from January 1st 2010 to 31st December 2013 with a diagnosis of FA who subsequently underwent surgical excision biopsy. All cases with associated LN including ALH and classical LCIS were selected. We excluded cases with coexistent ductal carcinoma in situ (DCIS), invasive carcinoma, LN associated with necrosis, pleomorphic lobular carcinoma in situ (PLCIS) or lesions which would require excision in their own right (papilloma, radial scar, atypical ductal hyperplasia (ADH) or flat epithelial atypia (FEA)). Cases in which the radiologic targeted mass was discordant with a diagnosis of FA were also excluded. RESULTS: 2878 consecutive CNB with a diagnosis of FA were identified. 25 cases had a diagnosis of concomitant ALH or classical LCIS. Our study cohort consisted of 21 women with a mean age 53 years (age range 41-70 years). The core biopsy diagnosis was of LCIS and FA in 16 cases and ALH and FA in 5 cases. On excision biopsy, a FA was confirmed in all 21 cases. In addition to the FA, residual LCIS was present in 14 cases with residual ALH in 2 cases. One of the twenty-one cases (4.8%) was upgraded to invasive ductal carcinoma on excision.


Subject(s)
Breast Carcinoma In Situ/therapy , Breast Neoplasms/therapy , Fibroadenoma/therapy , Mastectomy, Segmental , Watchful Waiting , Adult , Aftercare , Aged , Biopsy, Large-Core Needle , Breast Carcinoma In Situ/complications , Breast Carcinoma In Situ/diagnostic imaging , Breast Carcinoma In Situ/pathology , Breast Neoplasms/complications , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Cohort Studies , Disease Management , Female , Fibroadenoma/complications , Fibroadenoma/diagnostic imaging , Fibroadenoma/pathology , Humans , Hyperplasia , Mammography , Middle Aged , Retrospective Studies
3.
Breast ; 30: 54-58, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27611236

ABSTRACT

OBJECTIVES: The information needs of cancer patients are highly variable. Literature suggests an improved ability to modulate personalised stress, increased patient involvement with decision making, greater satisfaction with treatment choices and reduced anxiety levels in cancer patients who have access to information. The aim of this project was to evaluate the effects of a mobile information application on anxiety levels of patients undergoing surgery for breast cancer. MATERIALS AND METHODS: An application was developed for use with Apple iPad containing information on basic breast cancer biology, different treatments used and surgical techniques. Content and face validity studies were performed. A randomized control trial was designed, with a 1:2 allocation. Data collected include basic demographics and type of surgery. Questionnaires used included: the HADS, Mini-MAC, information technology familiarity and information satisfaction. RESULTS: A total of 39 women participated. 13 women had access to an iPad containing additional information and 26 women acted as controls. The mean age was 54 and technology familiarity was similar among both groups. Anxiety and depression scores at seven days were significantly lower in control patients without access to the additional information provided by the mobile application (p = 0.022 and 0.029 respectively). CONCLUSION: Anxiety and depression in breast cancer patients is both multifactorial and significant, with anxiety levels directly correlating with reduced quality of life. Intuitively, information should improve anxiety levels, however, we have demonstrated that surgical patients with less information reported significantly lower anxiety. We advise the thorough testing and auditing of information initiatives before deployment.


Subject(s)
Access to Information/psychology , Adaptation, Psychological , Anxiety/psychology , Breast Neoplasms/surgery , Depression/psychology , Mobile Applications , Patient Education as Topic/methods , Preoperative Care/methods , Stress, Psychological/psychology , Breast Neoplasms/psychology , Computers, Handheld , Female , Humans , Middle Aged , Patient Satisfaction , Pilot Projects , Quality of Life , Surveys and Questionnaires
4.
Ann Surg Oncol ; 22 Suppl 3: S385-90, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26240010

ABSTRACT

BACKGROUND: Papillary lesions of the breast are a relatively rare, but heterogeneous group ranging from benign to atypical and malignant. Debate exists regarding the optimal management of these lesions. In the absence of more accurate risk-stratification models, traditional management guidelines recommend surgical excision, despite the majority of lesions proving benign. This study sought to determine the rate of malignancy in excised breast papillomas and to elucidate whether there exists a population in which surgical excision may be unnecessary. METHODS: A multicenter international retrospective review of core biopsy diagnosed breast papillomas and papillary lesions was performed between 2009 and 2013, following institutional ethical approval. Patient demographics, histopathological, and radiological findings were recorded. All data was tabulated, and statistical analysis performed using Stata. RESULTS: A total of 238 patients were included in the final analysis. The age profile of those with benign pathology was significantly younger than those with malignant pathology (p < 0.001). Atypia on core needle biopsy was significantly associated with a final pathological diagnosis of malignancy (OR = 2.73). The upgrade rate from benign core needle biopsy to malignancy on the final pathological sample was 14.4 %; however, only 3.7 % had invasive cancer. CONCLUSIONS: This international dataset is one of the largest in the published literature relating to breast papillomas. The overall risk of malignancy is significantly associated with older age and the presence of atypia on core needle biopsy. It may be possible to stratify higher-risk patients according to age and core needle biopsy findings, thereby avoiding surgery on low-risk patients.


Subject(s)
Breast Neoplasms/pathology , Carcinoma, Papillary/pathology , Papilloma/pathology , Adult , Aged , Breast Neoplasms/surgery , Carcinoma, Papillary/surgery , Female , Follow-Up Studies , Humans , International Agencies , Middle Aged , Neoplasm Staging , Papilloma/surgery , Prognosis , Retrospective Studies
6.
J Anim Sci ; 88(8): 2604-10, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20382876

ABSTRACT

The physiological role of cumulus cells (CC) surrounding oocytes is particularly important for normal cytoplasmic maturation of oocytes. However, removal of CC from oocytes is inevitable for some embryo manipulation techniques, such as germinal vesicle (GV) transfer, somatic cell haploidization, and oocyte cryopreservation. The present study was designed to determine an optimal method to culture porcine denuded oocytes (DO). The results indicated CC from cumulus-oocyte complexes at the GV stage (GVCC) or at the metaphase II stage, and mural granulosa cells could not improve the maturation of DO. However, GVCC could enhance the development of matured porcine DO after fertilization; the percentage of blastocysts was increased from 1.1 to 17.2% (P < 0.05), and the relative value of the x-axis and y-axis of spindles was also increased (P < 0.05). Coculture with GVCC had no effect on the distribution of mitochondria and cortical granules. The results contribute to our understanding of the mechanisms by which CC promote oocyte maturation and contribute to optimization of protocols for in vitro maturation of DO.


Subject(s)
Blastocyst/physiology , Cumulus Cells/physiology , Oocytes/growth & development , Animals , Coculture Techniques/methods , Female , Fertilization in Vitro/veterinary , Granulosa Cells/physiology , Metaphase/physiology , Microscopy, Fluorescence/veterinary , Mitochondria/physiology , Oocytes/physiology , Oocytes/ultrastructure , Spindle Apparatus/physiology
7.
Clin Rheumatol ; 25(6): 789-93, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16572289

ABSTRACT

To examine the expression of the apoptosis regulatory protein, Bcl-x(L), in the synovium of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). Immunohistochemistry for Bcl-x(L) was carried out on synovial samples from patients with RA and OA. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis were performed to qualitatively examine the expression of Bcl-x(L). Bcl-x(L) expression was detected in the lining, endothelium and inflammatory cells of both RA (n=20) and OA (n=10) samples. However, there was significantly more expression in the lining of RA synovium compared to OA (77 vs 61%, p<0.05). Many of the positive cells in the RA subsynovium were noted to be plasma cells. There was a significant correlation between Bcl-x(L) expression and the number of inflammatory cells in the subsynovium of RA and OA patients (r (s)=0.376, p<0.05, n=30). Age and disease duration did not correlate with Bcl-x(L) expression in rheumatoid patients. Bcl-x(L) may play a role in the extended survival of synoviocytes and inflammatory cells in rheumatoid synovium.


Subject(s)
Arthritis, Rheumatoid/metabolism , Synovial Membrane/metabolism , bcl-X Protein/metabolism , Aged , Aging/metabolism , Arthritis, Rheumatoid/pathology , Blotting, Western , Endothelial Cells/metabolism , Female , Humans , Immunohistochemistry , Male , Middle Aged , Osteoarthritis/metabolism , Osteoarthritis/pathology , Plasma Cells/metabolism , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Staining and Labeling , Synovial Membrane/pathology , Time Factors , bcl-X Protein/genetics
9.
Gut ; 53(5): 694-700, 2004 May.
Article in English | MEDLINE | ID: mdl-15082588

ABSTRACT

BACKGROUND: We and others have reported the prophylactic efficacy of oral consumption of probiotic lactobacilli in the interleukin 10 knockout (IL-10 KO) model of colitis. It has not been demonstrated that the oral route is essential for probiotic efficacy. AIMS: (i) To determine the effect of parenteral administration (subcutaneous) of Lactobacillus salivarius 118 on colitis of IL-10 KO mice; and (ii) to determine if observed responses are disease specific. METHODS: (i) IL-10 KO mice were injected subcutaneously with L salivarius 118 or saline over 19 weeks. At sacrifice, the bowels were histologically scored. Isolated splenocytes were cultured in vitro and cytokine levels measured. (ii) In the collagen induced arthritis model, DBA/1 mice were injected subcutaneously with the probiotic or saline. At sacrifice, paw thickness was measured and joints were histologically scored. RESULTS: (i) Colonic inflammatory scores were significantly decreased in IL-10 KO mice injected with L salivarius 118 compared with controls (p<0.05). Proinflammatory cytokine production from stimulated splenocytes was significantly lower for the probiotic group whereas stimulated transforming growth factor beta (TGF-beta) levels were significantly increased (p<0.05). (ii) Scoring of arthritis and paw thickness were significantly improved in the group of mice injected with L salivarius 118 compared with controls. CONCLUSIONS: (1) Subcutaneous administration of L salivarius 118 significantly attenuated colitis in the IL-10 KO model and suppressed collagen induced arthritis, suggesting that the oral route may not be essential for probiotic anti-inflammatory effects and that responses are not disease specific. (2) The probiotic effect was associated with reduced production of proinflammatory (T helper 1) cytokines and maintained production of anti-TGF-beta.


Subject(s)
Arthritis, Experimental/prevention & control , Colitis/therapy , Probiotics/administration & dosage , Animals , Arthritis, Experimental/pathology , Cells, Cultured , Colitis/immunology , Colitis/pathology , Cytokines/biosynthesis , Female , Injections, Subcutaneous , Lactobacillus , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Probiotics/therapeutic use , Random Allocation , Spleen/immunology
11.
Br J Cancer ; 89(7): 1345-51, 2003 Oct 06.
Article in English | MEDLINE | ID: mdl-14520470

ABSTRACT

Many cancers express Fas ligand (FasL/CD95L) in vivo, and can kill lymphoid cells by Fas-mediated apoptosis in vitro. However, overexpression of recombinant FasL in murine tumour allografts revealed a potential antitumour effect of FasL, via recruitment of neutrophils. Transforming growth factor-beta1 (TGF-beta1) could inhibit these neutrophil-stimulatory effects of FasL. In the present study, we sought to determine directly whether FasL contributes to immune privilege or tumour rejection in human colon cancers in vivo, and whether TGF-beta1 regulates FasL function. Serial tumour sections were immunostained for FasL and TGF-beta1. Neutrophils and tumour infiltrating lymphocytes (TILs) were detected by immunohistochemistry for lactoferrin and CD45, respectively. Apoptotic TIL were identified by dual staining for TUNEL/CD45. FasL expression by nests of tumour cells was associated with a mean four-fold depletion of TILs (range 1.8-33-fold, n=16, P<0.001), together with a two-fold increase in TIL apoptosis (range 1.6-2.5-fold, n=14, P<0.001), relative to FasL-negative nests within the same tumours. The overall level of neutrophils present in all tumours examined was low (mean 0.3%, n=16), with FasL expression by tumour nests associated with a mean two-fold decrease in neutrophils, irrespective of TGF-beta1 expression. Together, our results suggest that tumour-expressed FasL is inhibitory rather than stimulatory towards antitumour immune responses.


Subject(s)
Colonic Neoplasms/immunology , Membrane Glycoproteins/physiology , Transforming Growth Factor beta/metabolism , Colonic Neoplasms/pathology , Fas Ligand Protein , Humans , Immunity, Cellular , Immunoenzyme Techniques , In Situ Nick-End Labeling , Lactoferrin/metabolism , Leukocyte Common Antigens/metabolism , Ligands , Lymphocyte Depletion , Lymphocytes, Tumor-Infiltrating/immunology , Neutrophils/immunology , Paraffin Embedding , Transforming Growth Factor beta1
12.
Gut ; 51(5): 665-70, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12377804

ABSTRACT

BACKGROUND AND AIMS: The uncertainty surrounding the role of Mycobacterium avium subsp paratuberculosis (Map) in Crohn's disease has been compounded by possible contamination from Map present in the lumen microflora. This study used laser capture microdissection (LCM) and polymerase chain reaction (PCR) to detect Map DNA in subepithelial granulomas, isolated from 15 surgically resected, formalin fixed specimens of granulomatous Crohn's disease and from 12 granulomatous disease controls (10 bowel, 2 non-bowel). METHODS: The effect of amplicon size on reliability of PCR from formalin fixed samples was examined by amplifying 435 bp and 133 bp sequences of the human APC gene. After this, nested primers were designed to detect a small fragment (155 bp) of the Map specific IS900 gene in Crohn's granulomas. LCM isolated granulomas from Map culture positive bovine intestine was used as positive control. PCR product specificity was confirmed by direct DNA sequencing. RESULTS: The smaller, but not the larger, fragment of the APC gene amplified reliably in all samples. Amplification of the 155 bp fragment of the IS900 gene detected Map DNA in microdissected Crohn's granulomas in 6 of 15 cases, and in 0 of 12 disease control granulomas. CONCLUSIONS: LCM can be used to detect Map DNA in granulomas in a proportion of patients with Crohn's disease. However, formalin fixation requires that comparatively short DNA fragments of the Map specific IS900 gene be targeted, to permit consistent detection. Detection of Map DNA within granulomas might suggest an infectious aetiology in a subset of patients; alternatively, a transmissible agent may not be involved but mycobacterial DNA may influence pathogenesis by modifying the local cytokine responses.


Subject(s)
Crohn Disease/microbiology , Granuloma/microbiology , Intestines/microbiology , Mycobacterium avium subsp. paratuberculosis/genetics , RNA, Messenger/analysis , Case-Control Studies , Crohn Disease/surgery , DNA Primers , Dissection/methods , Humans , Intestines/surgery , Lasers , Polymerase Chain Reaction/methods , Sensitivity and Specificity
13.
Biochem Biophys Res Commun ; 290(4): 1308-14, 2002 Feb 01.
Article in English | MEDLINE | ID: mdl-11812006

ABSTRACT

Various members of the tumor necrosis factor receptor superfamily are implicated in the regulation of enterocyte apoptosis. Previously, we observed that human intestinal epithelial cells are rather unsusceptible to Fas-induced apoptosis. In the present study we analyzed these protective mechanisms in the human intestinal epithelial cell line HIEC, focusing on antiapoptotic molecules of the IAP family which block apoptosis at the level of the caspase cascade. HIEC expressed all key molecules required to trigger Fas-induced apoptosis. However, no apoptosis occurred after activation of Fas, whereas an upregulation of antiapoptotic cIAP1 and 2 was observed. Suppression of this upregulation with the proteasome inhibitor MG132 or the protein synthesis inhibitor cycloheximide highly sensitized HIEC toward Fas-induced apoptosis. Western blot analyses revealed that both inhibitors potently suppressed endogenously produced cIAP1 and 2. No effect was observed on XIAP expression. These data indicate that enterocytes are particularly protected against Fas-induced apoptosis on the level of executionary caspases.


Subject(s)
Adaptor Proteins, Signal Transducing , Apoptosis/physiology , Enterocytes/cytology , Enterocytes/metabolism , Intracellular Signaling Peptides and Proteins , Proteins/metabolism , fas Receptor/metabolism , Apoptosis/drug effects , Apoptosis/genetics , CASP8 and FADD-Like Apoptosis Regulating Protein , Carrier Proteins/genetics , Carrier Proteins/metabolism , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/genetics , Caspases/metabolism , Cell Line , Cycloheximide/pharmacology , Down-Regulation , Fas-Associated Death Domain Protein , Humans , Inhibitor of Apoptosis Proteins , Leupeptins/pharmacology , NF-kappa B/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Ubiquitin-Protein Ligases , Up-Regulation , fas Receptor/genetics
14.
J Clin Pathol ; 54(8): 598-604, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11477113

ABSTRACT

BACKGROUND/AIMS: Fas ligand (FasL) is a mediator of apoptosis via the Fas receptor (Fas/CD95/APO-1). Normal colonic epithelium expresses Fas, and appears to be relatively sensitive to Fas mediated apoptosis. Colonic adenocarcinomas coexpress FasL and Fas without undergoing widespread apoptosis. This study investigates the expression of FasL in colonic carcinogenesis from the earliest stages of the adenoma-carcinoma sequence. METHODS: FasL expression was determined in colonic adenomas (n = 38) of varying degrees of dysplasia and histological type by immunohistochemistry. Adenomas that contained areas of carcinomatous change were included (n = 12 of 38). Normal colonic epithelium (n = 10), hyperplastic polyps (n = 8), and serrated adenomas (n = 3) from patients without colonic adenocarcinomas were used for comparison. Cell death was detected in situ in adenomas using TUNEL (terminal transferase mediated dUTP nick end labelling). RESULTS: In normal colonic epithelium and hyperplastic polyps, FasL expression was restricted to the luminal surface of the crypts, where Fas-FasL coexpression was coincident with a high frequency of TUNEL positive epithelial cells. All adenomas (n = 38) had an altered distribution of positive FasL staining; FasL expression was found in most cells (> 70% of neoplastic cells). Expression of Fas was also detected throughout the adenomas, but coexpression of FasL and Fas was not associated with TUNEL positivity in most cells. CONCLUSIONS: FasL upregulation occurs early in the adenoma-carcinoma sequence of colon carcinogenesis, and is evident at the level of mild dysplasia. The lack of pronounced apoptosis in areas of adenomas coexpressing Fas and FasL suggests that colonocytes acquire resistance to Fas mediated apoptosis early in the transformation process.


Subject(s)
Adenoma/metabolism , Carcinoma/metabolism , Colonic Neoplasms/metabolism , Membrane Glycoproteins/metabolism , Neoplasm Proteins/metabolism , Up-Regulation , fas Receptor/metabolism , Adenoma/pathology , Apoptosis , Carcinoma/pathology , Colon/metabolism , Colonic Neoplasms/pathology , Colonic Polyps/metabolism , Colonic Polyps/pathology , Fas Ligand Protein , Humans , Immunohistochemistry/methods , In Situ Nick-End Labeling , Membrane Glycoproteins/analysis
15.
J Surg Res ; 98(1): 27-32, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11368534

ABSTRACT

INTRODUCTION: Ileal pouch-anal anastomosis (IPAA) remains the gold standard for patients with refractory ulcerative colitis. Pouchitis causes considerable morbidity in 40% of patients with IPAA. This study examined the role of increased epithelial apoptosis in the etiology of pouchitis. METHODS: Following ethical approval pouch biopsies taken from patients with a history of pouchitis were compared with age-matched controls from patients who were pouchitis free. Apoptosis was detected immunohistochemically using a monoclonal antibody (M30) and terminal deoxyribonucleotidyl transferase (TDT)-mediated dUTP-digoxigenin end labeling (TUNEL). Villous atrophy was assessed histologically and correlated with levels of apoptosis. Epithelial Fas-ligand (L) was also assessed immunohistochemically. RESULTS: A significant increase in TUNEL staining was seen at the epithelial but not at the lamina propria level for known pouchitis patients versus controls (0.091 vs 0.035; P < 0.01). Similarly, epithelial M30 immunoreactivity (0.225 vs 0.082; P < 0.05) and villous atrophy (0.035 vs 0.10; P < 0.05) were significantly increased in pouches with previous pouchitis when compared with normal pouches. Upregulation of Fas-L expression was characteristic of this epithelium. Mononuclear cells were strongly positive for Fas-L. Increased epithelial levels of apoptosis correlated with increased levels of villous atrophy. CONCLUSIONS: Our data suggest a role for elevated Fas-Fas-L (CD95-CD95L)-mediated epithelial apoptosis in the etiology of pouchitis. Increased levels of villous atrophy may result from increased apoptosis and thereby predispose to infection by otherwise apathogenic organisms.


Subject(s)
Apoptosis/physiology , Ileum/physiopathology , Intestinal Mucosa/physiopathology , Membrane Glycoproteins/physiology , Pouchitis/physiopathology , fas Receptor/physiology , Adolescent , Adult , Antibodies, Monoclonal , Atrophy , Child , Fas Ligand Protein , Humans , Ileum/pathology , Immunohistochemistry , In Situ Nick-End Labeling , Intestinal Mucosa/pathology , Membrane Glycoproteins/metabolism , Microvilli/pathology , Middle Aged , Pouchitis/pathology , Up-Regulation
16.
Nat Med ; 7(3): 271-4, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11231613

ABSTRACT

Fas ligand (FasL) has become an enigmatic molecule: some evidence indicates that it contributes to immune privilege in tissues and tumors, whereas other data demonstrates that FasL can elicit inflammation. New findings may begin to reconcile the paradoxical effects of FasL.


Subject(s)
Inflammation/immunology , Membrane Glycoproteins/immunology , Fas Ligand Protein , Humans , Membrane Glycoproteins/genetics , Neoplasms/immunology , RNA, Messenger/genetics
17.
J Cell Physiol ; 185(3): 331-8, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11056003

ABSTRACT

Homeostasis in the colonic epithelium is achieved by a continuous cycle of proliferation and apoptosis, in which imbalances are associated with disease. Inflammatory bowel disease (IBD) and colon cancer are associated with either excessive or insufficient apoptosis of colonic epithelial cells, respectively. By using two colonic epithelial cell lines, HT29 and SW620, we investigated how the epithelial cell's sensitivity to apoptosis was regulated by the proinflammatory cytokine interferon-gamma (IFN-gamma). We found that IFN-gamma sensitized HT29 cells, and to a lesser extent SW620, to diverse inducers of apoptosis of physiologic or therapeutic relevance to the colon. These apoptosis inducers included Fas (CD95/APO-1) ligand (FasL), short-chain fatty acids, and chemotherapeutic drugs. The extent of IFN-gamma-mediated apoptosis sensitization in these two cell lines correlated well with the degree of IFN-gamma-mediated upregulation of the proapoptotic protease caspase-1. Although IFN-gamma alone effectively sensitized HT29 cells to apoptosis, inclusion of the protein synthesis inhibitor cyclohexamide (CHX) during apoptotic challenge was necessary for maximal sensitization of SW620. The requirement of CHX to sensitize SW620 cells to apoptosis implies a need to inhibit translation of antiapoptotic proteins absent from HT29. In particular, the antiapoptotic protein Bcl-2 was strongly expressed in SW620 cells but absent from HT29. Our results indicate that IFN-gamma increases the sensitivity of colonic epithelial cells to diverse apoptotic stimuli in concert, via upregulation of caspase-1. Our findings implicate caspase-1 and Bcl-2 as important central points of control determining the general sensitivity of colonic epithelial cells to apoptosis.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Colon/pathology , Interferon-gamma/pharmacology , Intestinal Mucosa/pathology , Cell Line , Colon/drug effects , Drug Synergism , Fas Ligand Protein , Fatty Acids, Volatile/pharmacology , Humans , Intestinal Mucosa/drug effects , Membrane Glycoproteins/pharmacology
18.
Ann N Y Acad Sci ; 910: 178-92; discussion 193-5, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10911913

ABSTRACT

Fas (CD95/APO-1) is a cell surface "death receptor" that mediates apoptosis upon engagement by its ligand, FasL. Fas-mediated apoptosis of lymphocytes normally serves immunoregulatory roles, including tolerance acquisition, immune response termination, and maintenance of immune privilege in certain organs. Colon tumors can exploit this lymphocyte death program by expressing FasL. This may enable colon tumors to mount a "Fas counterattack" against antitumor lymphocytes, impairing antitumor immune responses. FasL-expressing colon tumor-derived cell lines can trigger Fas-mediated apoptosis of cocultured T cells in vitro. FasL expressed in esophageal cancer has been significantly associated with apoptosis and depletion of tumor-infiltrating lymphocytes (TIL) in vivo. FasL may also facilitate metastatic colonization of Fas-sensitive organs such as the liver, by inducing apoptosis of target organ cells. Normal colonic epithelial cells express Fas and are relatively sensitive to Fas-mediated apoptosis. By contrast, colon tumor-derived cell lines are usually resistant to induction of Fas-mediated apoptosis, and colon cancer cells frequently coexpress Fas and FasL. The mechanisms allowing resistance to Fas-mediated apoptosis are complex, and defects have been identified at several levels of Fas signal transduction. The "Bcl-2 rheostat" may be pitched against apoptosis in colon cancer, inasmuch as overexpression of Bcl-2, downregulation of Bak, and mutation of Bax are common defects in colon tumors. Caspase-1 is also downregulated in colon cancer. The high frequency of p53 mutations in late-stage cancers may also inhibit Fas signaling. Fundamental defects in apoptosis signaling may contribute to both immuno- and chemoresistance in colon cancer and allow expression of FasL to counterattack antitumor lymphocytes.


Subject(s)
Apoptosis/immunology , Colonic Neoplasms/immunology , Colonic Neoplasms/pathology , Membrane Glycoproteins/immunology , fas Receptor/immunology , Cell Survival/immunology , Fas Ligand Protein , Humans , Signal Transduction/immunology
19.
Dis Esophagus ; 12(2): 83-9, 1999.
Article in English | MEDLINE | ID: mdl-10466039

ABSTRACT

The mechanisms by which esophageal tumors escape immunologic recognition and clearance are only partly understood at the molecular level. Esophageal cancers have been shown to evade host recognition by down-regulation of antigen presentation and production of immunosuppressive factors. Recently, two independent reports have shown that esophageal tumor cells abundantly express Fas ligand (FasL) in vivo. As the triggering agonist for Fas receptor (Fas or APO-1/CD95)-mediated apoptosis of lymphocytes, FasL normally plays immune down-regulatory roles, including activation-induced cell death of T and B cells, as well as maintaining immune privilege in certain organs. Fas ligand expressed by esophageal cell lines has been shown to induce apoptosis of cocultured Fas-sensitive lymphoid cells in vitro. FasL expression by esophageal carcinomas in vivo has been associated with significantly reduced tumor-infiltrating lymphocytes (TILs) in FasL-positive tumor nests, concomitant with significantly increased TIL apoptosis in these nests. These studies support a 'Fas counterattack' mechanism of immune escape in esophageal cancer. By expressing functional Fas ligand, esophageal cancer cells can deplete antitumor lymphocytes by inducing apoptosis. To express functional FasL, esophageal carcinomas also acquire molecular mechanisms to resist autocrine Fas-mediated apoptosis of tumor cells.


Subject(s)
Apoptosis , Esophageal Neoplasms/immunology , Membrane Glycoproteins/immunology , Receptors, Tumor Necrosis Factor/immunology , fas Receptor/immunology , Esophageal Neoplasms/pathology , Fas Ligand Protein , Humans , Lymphocyte Subsets/immunology , Lymphocytes, Tumor-Infiltrating/immunology
20.
Dis Esophagus ; 12(2): 90-8, 1999.
Article in English | MEDLINE | ID: mdl-10466040

ABSTRACT

Fas (CD95/Apo-1) receptor (FasR) is a cell-surface receptor that mediates apoptotic cell death upon triggering by Fas ligand (FasL). We sought to determine whether normal human esophageal epithelial cells express FasL and/or FasR and whether their localization is consistent with a role in the turnover of normal esophageal epithelium. Normal esophageal epithelium was immunohistochemically positive for FasL in upper prickle cell layers and in mature squamous cells, but the proliferative basal layer was negative. FasL mRNA was detected in the same epithelial cell layers by in situ hybridization. Co-localization of FasL mRNA and protein therefore confirmed that FasL expression is induced in esophageal epithelial cells as they reach terminal differentiation. FasR was immunohistochemically detected throughout the esophageal epithelium. Positive TUNEL (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling) staining confirmed cell death of the FasL and FasR coexpressing mature epithelial cells. CD45-positive immunocytes were notably absent from FasL-expressing upper epithelial layers. The findings are consistent with a contributory role for Fas-mediated autocrine suicide or paracrine fratricide in the apoptotic turnover of normal esophageal epithelium.


Subject(s)
Apoptosis , Esophageal Neoplasms/chemistry , Esophagus/chemistry , Membrane Glycoproteins/analysis , Receptors, Tumor Necrosis Factor/analysis , fas Receptor/analysis , Epithelial Cells/chemistry , Epithelial Cells/pathology , Esophageal Neoplasms/pathology , Esophagus/pathology , Fas Ligand Protein , Humans , Immunoenzyme Techniques , In Situ Hybridization , Leukocyte Common Antigens/analysis , RNA, Messenger/genetics
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