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1.
Ann Oncol ; 30(2): 317-324, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30428063

ABSTRACT

BACKGROUND: Advanced melanoma treatments often rely on immunotherapy or targeting mutations, with few treatment options for wild-type BRAF (BRAF-wt) melanoma. However, the mitogen-activated protein kinase pathway is activated in most melanoma, including BRAF-wt. We assessed whether inhibiting this pathway by adding kinase inhibitors trametinib or pazopanib to paclitaxel chemotherapy improved outcomes in patients with advanced BRAF-wt melanoma in a phase II, randomised and open-label trial. PATIENTS AND METHODS: Patients were randomised (1 : 1 : 1) to paclitaxel alone or with trametinib or pazopanib. Paclitaxel was given for a maximum of six cycles, while 2 mg trametinib and 800 mg pazopanib were administered orally once daily until disease progression or unacceptable toxicity. Participants and investigators were unblinded. The primary end point was progression-free survival (PFS). Key secondary end points included overall survival (OS) and objective response rate (ORR). RESULTS: Participants were randomised to paclitaxel alone (n = 38), paclitaxel and trametinib (n = 36), or paclitaxel and pazopanib (n = 37). Adding trametinib significantly improved 6-month PFS [time ratio (TR), 1.47; 90% confidence interval (CI) 1.08-2.01, P = 0.04] and ORR (42% versus 13%; P = 0.01) but had no effect on OS (P = 0.25). Adding pazopanib did not benefit 6-month PFS; (TR 1.36; 90% CI 0.96-1.93; P = 0.14), ORR, or OS. Toxicity increased in both combination arms. CONCLUSION: In this phase II trial, adding trametinib to paclitaxel chemotherapy for BRAF-wt melanoma improved PFS and substantially increased ORR but did not impact OS.This study was registered with the EU Clinical Trials Register, EudraCT number 2011-002545-35, and with the ISRCTN registry, number 43327231.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Melanoma/drug therapy , Mutation , Proto-Oncogene Proteins B-raf/genetics , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Indazoles , Male , Melanoma/genetics , Melanoma/pathology , Middle Aged , Paclitaxel/administration & dosage , Prognosis , Pyridones/administration & dosage , Pyrimidines/administration & dosage , Pyrimidinones/administration & dosage , Sulfonamides/administration & dosage , Survival Rate
2.
Ann Oncol ; 26(9): 1865-1870, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26037797

ABSTRACT

BACKGROUND: Following inguinal orchidectomy, management options for patients with stage I seminoma include initial surveillance or treatment with adjuvant radiotherapy or chemotherapy. The anticipated relapse rate for patients followed by surveillance alone is ∼15%, with adjuvant treatment this risk is reduced to ∼4%-5% at 5 years. After carboplatin treatment, follow-up strategies vary and there are no validated, predictive markers of relapse. PATIENTS AND METHODS: We conducted a retrospective analysis of all patients presenting with stage I seminoma who received a single cycle of adjuvant carboplatin in South Central England between 1996 and 2013. We report on outcome and the results of univariate and multivariate analysis evaluating possible risk factors for post carboplatin relapse. RESULTS: A total of 517 eligible patients were identified. All underwent nuclear medicine estimation of glomerular filtration rate before treatment with carboplatin (dosed at area under the curve × 7). With a median follow-up of 47.2 months (range 0.4-214 months), 21/517 patients have relapsed resulting in a 5-year estimated relapse-free survival of 95.0% (95% confidence interval 92.8% to 97.3%). Median time to relapse was 22.7 months (range 12.5-109.5 months). Relapse beyond 3 years was rare (4/517; 0.8%). Twenty of 21 (95%) relapsed patients had retroperitoneal lymph node metastases. The majority (16/21; 76%) of patients had elevated tumour markers at relapse. Twenty of 517 (3.9%) patients developed a new contralateral testicular germ-cell cancer. There were no seminoma-related deaths. Tumour size was the only variable significantly associated with an increased risk of relapse. CONCLUSIONS: Overall results for this large cohort of patients confirm an excellent prognosis for these patients with outcomes equivalent to those seen in prospective clinical trials. Increasing tumour size alone appears to be associated with an increased risk of post chemotherapy relapse.


Subject(s)
Antineoplastic Agents/therapeutic use , Carboplatin/therapeutic use , Neoplasm Recurrence, Local/pathology , Neoplasms, Germ Cell and Embryonal/drug therapy , Seminoma/drug therapy , Testicular Neoplasms/drug therapy , Adolescent , Adult , Aged , Chemotherapy, Adjuvant , Combined Modality Therapy , Disease-Free Survival , Humans , Lymphatic Metastasis/pathology , Male , Middle Aged , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Staging , Neoplasms, Germ Cell and Embryonal/surgery , Orchiectomy , Retrospective Studies , Seminoma/surgery , Testicular Neoplasms/surgery , Treatment Outcome , Young Adult
3.
Eur J Cancer Care (Engl) ; 24(2): 155-62, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25620269

ABSTRACT

Bladder cancer is a disease of the elderly. Older patients might potentially be undertreated due to assumptions about benefit versus risk. Our objective was to determine outcomes in older patients receiving neoadjuvant chemotherapy for muscle-invasive bladder cancer (MIBC). We hypothesised that appropriately selected elderly patients (≥70 years) with MIBC could have similar clinical outcomes, and be safely treated, with standard neoadjuvant chemotherapy prior to definitive cystectomy or radiotherapy. We utilised a single institution case series analysis of patients with T2-4a N0 M0 transitional cell carcinoma of the bladder treated with cisplatin-based neoadjuvant chemotherapy between 2005 and 2011. Eighty-three patients were eligible. Median age was 68 (range 48-80), 33 patients (40%) were ≥70 years. Overall survival at 3 years was 65.8% (≥70) and 63.2% (<70) (P = 0.653), relapse-free survival at 3 years was 61.6% and 54.8% respectively (P = 0.471). The rates going forward to definitive local therapy (87.9% ≥ 70 and 84.0% < 70) and the pathological complete response rate (31.3% ≥ 70 and 40% < 70) were similar. Disease relapse rate was also similar (63.6% ≥ 70 vs. 60% < 70, P = 0.906). Elderly patients with good functional status and limited comorbidities diagnosed with MIBC receiving standard neoadjuvant chemotherapy followed by cystectomy or radiotherapy can have similar clinical outcomes as their younger counterparts. Prospective studies evaluating the optimum curative management in this elderly population are warranted.


Subject(s)
Antineoplastic Agents/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Transitional Cell/drug therapy , Cisplatin/administration & dosage , Neoadjuvant Therapy/methods , Urinary Bladder Neoplasms/drug therapy , Age Factors , Aged , Aged, 80 and over , Chemotherapy, Adjuvant , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Disease-Free Survival , Female , Humans , Male , Middle Aged , Patient Selection , Retrospective Studies , Survival Analysis , Gemcitabine
4.
Ann Oncol ; 25(8): 1591-7, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24669017

ABSTRACT

BACKGROUND: Seminoma stage I is the most frequent testis cancer and single-dose carboplatin (AUC7) is an effective and widely used adjuvant treatment. Underdosing of carboplatin by 10% has been shown to almost double the rate of relapse and hence correct dosing based on accurate GFR measurement is crucial. The gold standard of GFR measurement with a radiolabelled isotope is expensive and not readily available. In many institutions, it is replaced by GFR estimation with the Cockcroft-Gault formula, which might lead to significant carboplatin underdosing and potentially inferior clinical outcome. METHODS: Retrospective analysis of all patients with stage I seminoma treated with adjuvant carboplatin between 1999 and 2012. All patients had serum creatinine measured and underwent GFR measurement with a radioisotope ((51)Cr EDTA or (99m)Tc DTPA), which was compared with seven standard GFR estimation formulae (Cockcroft-Gault, CKD-EPI, Jelliffe, Martin, Mayo, MDRD, Wright) and a flat dosing strategy. Bias, precision, rates of under- and overdosing of GFR estimates were compared with measured GFR. Bland-Altman plots were done. RESULTS: A total of 426 consecutive Caucasian male patients were included: median age 39 years (range 19-60 years), median measured GFR 118 ml/min (51-209), median administered carboplatin dose 1000 mg (532-1638). In comparison to isotopic GFR measurement, a relevant proportion of patients would have received ≤ 90% of carboplatin dose through the use of GFR estimation formulae: 4% using Mayo, 9% Martin, 18% Cockcroft-Gault, 24% Wright, 63% Jelliffe, 49% MDRD and 41% using CKD-EPI. The flat dosing strategy, Wright and Cockcroft-Gault formulae, showed the smallest bias with mean percentage error of +1.9, +0.4 and +2.1, respectively. CONCLUSIONS: Using Cockcroft-Gault or any other formula for GFR estimation leads to underdosing of adjuvant carboplatin in a relevant number of patients with Seminoma stage I and should not be regarded as standard of care.


Subject(s)
Antineoplastic Agents/administration & dosage , Carboplatin/administration & dosage , Glomerular Filtration Rate/drug effects , Kidney/drug effects , Seminoma/drug therapy , Testicular Neoplasms/drug therapy , Adolescent , Adult , Cohort Studies , Dose-Response Relationship, Drug , Humans , Kidney/physiology , Kidney Function Tests , Male , Middle Aged , Neoplasm Recurrence, Local/etiology , Neoplasm Staging , Retrospective Studies , Risk , Seminoma/pathology , Seminoma/physiopathology , Testicular Neoplasms/pathology , Testicular Neoplasms/physiopathology , Young Adult
5.
Br J Cancer ; 110(7): 1759-66, 2014 Apr 02.
Article in English | MEDLINE | ID: mdl-24556622

ABSTRACT

BACKGROUND: Serum total human chorionic gonadotrophin ß subunit (hCGß) level might have prognostic value in urothelial transitional cell carcinoma (TCC) but has not been investigated for independence from other prognostic variables. METHODS: We utilised a clinical database of patients receiving chemotherapy between 2005 and 2011 for urothelial TCC and an independent cohort of radical cystectomy patients for validation purposes. Prognostic variables were tested by univariate Kaplan-Meier analyses and log-rank tests. Statistically significant variables were then assessed by multivariate Cox regression. Total hCGß level was dichotomised at < vs ≥2 IU l(-1). RESULTS: A total of 235 chemotherapy patients were eligible. For neoadjuvant chemotherapy, established prognostic factors including low ECOG performance status, normal haemoglobin, lower T stage and suitability for cisplatin-based chemotherapy were associated with favourable survival in univariate analyses. In addition, low hCGß level was favourable when assessed either before (median survival not reached vs 1.86 years, P=0.001) or on completion of chemotherapy (4.27 vs 0.42 years, P=0.000002). This was confirmed in multivariate analyses and in patients receiving first- and second-line palliative chemotherapy, and in a radical cystectomy validation set. CONCLUSIONS: Serum total hCGß level is an independent prognostic factor in patients receiving chemotherapy for urothelial TCC in both curative and palliative settings.


Subject(s)
Biomarkers, Tumor/blood , Carcinoma, Transitional Cell/blood , Carcinoma, Transitional Cell/drug therapy , Chorionic Gonadotropin, beta Subunit, Human/blood , Urinary Bladder Neoplasms/blood , Urinary Bladder Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Carcinoma, Transitional Cell/mortality , Female , Humans , Male , Middle Aged , Prognosis , Survival Analysis , Urinary Bladder Neoplasms/mortality , Urothelium/metabolism , Urothelium/pathology
6.
Int Endod J ; 45(11): 989-95, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22519883

ABSTRACT

AIM: To determine whether cells pre-stressed by known cytotoxic or inflammatory agents are more susceptible to the deleterious effects of a calcium hydroxide formulation used in pulp capping. METHODOLOGY: Adult human dermal fibroblasts were treated for 48 h with 0.001% chlorhexidine, 0.2% ethanol, 5 µg mL(-1) Escherichia coli lipopolysaccharide (LPS) or 0.05 mmol L(-1) nicotine. Cells were subsequently treated with the soluble materials extracted from Dycal pellets for an additional 24 h. Controls included cells cultured in medium only and cells exposed to Dycal only. Cytotoxicity was measured using colorimetric MTT, WST and secreted lactate dehydrogenase assays. In addition, mitotic activity was evaluated using a colorimetric histone H3 phosphorylation assay. Data were statistically analysed using anova with Tukey's multiple comparison post-test and significance at P ≤ 0.05. RESULTS: For all assays, measured values for cells treated with chlorhexidine, ethanol, LPS or nicotine plus the soluble materials extracted from Dycal pellets were significantly lower compared to control (P < 0.05) for all comparisons between experimental conditions. However, between treatments and for comparisons of treatments with Dycal, there were no differences observed for any assay. CONCLUSIONS: Calcium hydroxide in a formulation used in dental clinical procedures is highly cytotoxic to cultured cells, as evidenced by several cellular assays. However, other known toxic agents, including chlorhexidine, ethanol, bacterial LPS and nicotine, do not appear to function synergistically to increase the deleterious cellular effects of the calcium hydroxide in an in vitro model of cytotoxicity.


Subject(s)
Calcium Hydroxide/toxicity , Minerals/toxicity , Pulp Capping and Pulpectomy Agents/toxicity , Adult , Analysis of Variance , Antimitotic Agents/pharmacology , Cells, Cultured , Chlorhexidine/pharmacology , Drug Interactions , Escherichia coli/chemistry , Ethanol/pharmacology , Fibroblasts/drug effects , Humans , L-Lactate Dehydrogenase/pharmacology , Lipopolysaccharides/pharmacology , Materials Testing , Models, Chemical , Nicotine/pharmacology , Statistics, Nonparametric , Toxicity Tests
7.
Cell Prolif ; 37(2): 161-75, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15030550

ABSTRACT

Laminin-2 (LN-2, alpha2beta1gamma1) is a basement membrane-associated laminin isoform usually considered in the context of muscle and nerve tissues. To test the hypothesis that LN-2 can additionally modulate epithelial cell biology, an analysis of the role of LN-2 in cell adhesion, activation of signalling intermediates and proliferation was undertaken. A virally transformed human conjunctival epithelial cell line (HC0597) was utilized in this study. Adhesion assays using function-inhibiting antibodies demonstrated that alpha3beta1 integrin is essential for the rapid attachment of conjunctival epithelial cells to LN-2. Bromodeoxyuridine (BrdU) incorporation analyses revealed that, compared with LN-1 or LN-10, LN-2 significantly promotes epithelial proliferation. Phosphorylation of the signalling intermediates Erk1/2 and Akt-1 was observed within 15 min of cell adhesion to LN-2. Inhibiting alpha3beta1 integrin function decreased total cellular phosphotyrosine levels, specifically inhibited phosphorylation of Erk1/2 and Akt-1, and dampened the proliferation response of epithelial cells adherent to LN-2. Inhibition of Erk or Akt activation inhibited cell proliferation in a dose-dependent manner. However, the inhibition of Erk resulted in a stronger suppression of proliferation compared with Akt inhibition. From these results, it is concluded that human conjunctival epithelial cells adhere to immobilized LN-2 using alpha3beta1 integrin. alpha3beta1 integrin/LN-2 signalling, transduced primarily through an Erk pathway, enhances epithelial cell proliferation. These results demonstrate that LN-2 can impact on epithelial cell biology in addition to nerve and muscle, and provide information regarding the role of this isoform in ocular surface epithelial cells.


Subject(s)
Cell Communication/physiology , Conjunctiva/metabolism , Epithelial Cells/metabolism , Laminin/metabolism , Proto-Oncogene Proteins , Signal Transduction/physiology , Cell Adhesion/drug effects , Cell Adhesion/physiology , Cell Communication/drug effects , Cell Division/drug effects , Cell Division/physiology , Cell Line , Conjunctiva/cytology , Conjunctiva/drug effects , Enzyme Inhibitors/pharmacology , Epithelial Cells/cytology , Epithelial Cells/drug effects , Humans , Integrin alpha3beta1/antagonists & inhibitors , Integrin alpha3beta1/metabolism , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/metabolism , Phosphorylation/drug effects , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-akt , Signal Transduction/drug effects
8.
Apoptosis ; 8(6): 681-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14739614

ABSTRACT

The purpose of this study was to determine the effect of hypoxia on caspase-8 and -9 gene and protein expression and activity in corneal epithelium. Non-transformed human corneal epithelial cells (HCEC) were cultured in 2% oxygen. A cDNA expression array coupled with densitometric analysis was used to compare relative mRNA expression levels of 96 apoptosis-related genes in hypoxic and normoxic HCEC. Caspase-8, caspase-9, FLIP, Fas, FasL, and TNFalpha protein expression was assessed further using Western blot analysis and ELISA. Caspase-8 and -9 activities were measured using a fluorometric activity assay. Hypoxia did not affect caspase-8 or -9 gene or protein expression in HCEC, however caspase-9 activity was significantly increased. Hypoxia significantly suppressed the activity of caspase-8. FLIP and Fas gene and protein expression were not significantly altered in hypoxic cells compared to normoxic controls. mRNA and protein levels of TNFalpha and TNFR-1 were significantly decreased, while FasL mRNA and proteins levels were significantly increased in hypoxic HCEC. In corneal epithelium stressed by hypoxia caspase-9 activity is upregulated, suggesting that apoptosis proceeds via the mitochondrial pathway. Caspase-8 activity may be suppressed because the loss of TNFalpha and TNFR-1 gene and protein expression inhibits the initial formation of a death signaling complex.


Subject(s)
Caspases/metabolism , Cornea/metabolism , Epithelial Cells/metabolism , Hypoxia/metabolism , Apoptosis/physiology , Caspase 8 , Caspase 9 , Caspases/genetics , Humans
9.
J Cell Sci ; 114(Pt 22): 4033-40, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11739635

ABSTRACT

Laminin 5 functions to promote cell-matrix adhesion and therefore is hypothesized to abrogate apoptosis initiated through the loss of epithelial cell contact with extracellular matrix. Laminin 5 levels are decreased in epithelial cells cultured in a hypoxic environment. Exposure of epithelial cells to hypoxia may induce apoptotic pathways transmitted through changes in mitochondrial membrane potential. Using an apoptosis assay based on mitochondrial membrane integrity, the effect of hypoxia (2% oxygen) on human corneal epithelial cell viability was determined. Both a virally transformed corneal epithelial cell line and third passage corneal epithelial cells were resistant to hypoxia-mediated apoptosis for up to 5 days in culture. However, at 7 days in culture, a statistically significant increase in apoptosis was noted in hypoxic corneal epithelial cells compared to normoxic (20% oxygen) controls. Increased apoptosis in hypoxic epithelium at 7 days in culture correlated with decreased deposition of laminin 5 into the extracellular matrix, as determined by western blot analysis and immunofluorescence microscopy. Additionally, the extracellular processing of the alpha3 and gamma2 chains of laminin 5 was negatively impacted by corneal epithelial cell exposure to hypoxia for 7 days. Treatment of human corneal epithelial cells cultured in 20% oxygen with function-inhibiting antibodies to laminin 5 for 2 or 3 days resulted in a statistically significant decrease in proliferation, and concomitant increase in apoptosis, compared with untreated normoxic controls. Based on these results, it appears that mechanisms of hypoxia-mediated apoptosis in human corneal epithelial cells may be initiated by the loss of processed laminin 5 in the extracellular matrix or by the loss of laminin 5-epithelial cell communication and transmitted through mitochondria.


Subject(s)
Apoptosis/physiology , Cell Hypoxia/physiology , Epithelium, Corneal/metabolism , Laminin/metabolism , Cell Survival , Cells, Cultured , Epithelium, Corneal/cytology , Humans , Microscopy, Fluorescence , Oxygen/metabolism , Poly(ADP-ribose) Polymerases/metabolism
10.
Prog Histochem Cytochem ; 36(3): 185-259, 2001.
Article in English | MEDLINE | ID: mdl-11593936

ABSTRACT

The anterior surface of the eye is composed of the cornea, conjunctiva, and the zone between the two called the limbus. The cornea must maintain optical clarity to retain good vision. However, the ocular surface is vulnerable to trauma, microbial infection, and exposure to environmental toxins. This places the cornea, especially, at risk for disruptions of the epithelial barrier and subsequent immunopathological events. Cell-cell and cell-matrix attachment junctions incorporating adhesion molecules ensure that the epithelial barrier remains intact. Protein components of the basement membrane, including laminins, are vital to the adhesion of corneal epithelial cells to the underlying stroma and function to enhance the strength of the bond between epithelium and connective tissue. Epithelial cells also play an early and crucial role in the initiation of ocular surface responses should a potentially antigenic molecule enter into deeper corneal tissues. For example, epithelial cells may produce and release cytokines such as interleukin-1 (IL-1). The delicate balance between the matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are central to mechanisms regulating dissolution of the extracellular matrix that may be a consequence of infection or wound healing. Adhesion molecules, cytokines and chemokines, and MMPs and TIMPs thus participate in the corneal response to immunologic challenge or wounding. They may also be involved in corneal pathologies associated with genetic diseases, diabetes, and vitamin A deficiency. In addition these molecules are components of cellular pathways underlying the clinical complications often observed with contact lens wear and refractive surgeries used to improve visual acuity.


Subject(s)
Cornea/anatomy & histology , Cornea/physiology , Animals , Cornea/metabolism , Cornea/ultrastructure , Corneal Diseases/etiology , Corneal Diseases/pathology , Corneal Diseases/physiopathology , Corneal Diseases/therapy , Corneal Injuries , Humans
11.
Curr Eye Res ; 22(5): 353-7, 2001 May.
Article in English | MEDLINE | ID: mdl-11600936

ABSTRACT

PURPOSE: To determine if laminin-5 is retained in the matrix of cryopreserved human amniotic membrane tissue prepared for ocular surgeries. METHODS: Amniotic membrane was solubilized in urea/SDS buffer. Constituent proteins were resolved by SDS-PAGE and laminin-5 content was determined by Western blot analysis using a panel of antibodies directed against the alpha3, beta3 or gamma2 chains of the molecule. Human corneal epithelial cells were seeded on amniotic membrane and cultured in the presence or absence of EGF. The cell-membrane construct was examined for laminin-5 content using Western blot analysis and immunofluorescence microscopy. RESULTS: In preserved amniotic membrane the laminin-5 alpha3 chain is present in both the unprocessed (190-kDa) and processed (160-kDa) forms. The beta3 chain is found in the 145-kDa form. The gamma2 chain appears to be predominantly in the processed (105-kDa) form. Very little of the unprocessed form of the gamma2 chain (155-kDa) could be detected using immunoblot analysis. A similar distribution of laminin-5 was also present in extracts of corneal epithelial cells cultured on amniotic membrane. Immunofluorescence analysis of cells cultured on the membrane demonstrated polarization of laminin-5 at the cell-membrane interface. CONCLUSIONS: The presence of both the unprocessed and processed forms of laminin-5 alpha3 and gamma2 chains in preserved human amniotic membrane suggests that when used as a substrate in ocular surgeries, this membrane may be capable of promoting corneal epithelial cell motility and adhesion. Regulation of the motile or adhesive function may lie with factors secreted by the corneal epithelium that populates the membrane following surgery.


Subject(s)
Amnion/chemistry , Cryopreservation , Laminin/analysis , Tissue Preservation , Antibodies, Monoclonal , Blotting, Western , Cells, Cultured , Coculture Techniques , Cornea/chemistry , Cornea/cytology , Electrophoresis, Polyacrylamide Gel , Epithelial Cells/chemistry , Epithelial Cells/cytology , Fluorescent Antibody Technique, Indirect , Humans , Microscopy, Fluorescence
12.
Exp Eye Res ; 70(4): 537-46, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10866002

ABSTRACT

Both the laminin composition of the basement membrane and the keratin intermediate filament composition of the epithelial cell differs between cornea and conjunctiva, suggesting that at least some aspects of ocular surface epithelial cell differentiation may be regulated by extracellular matrix. The purpose of this study was to analyse the role of beta1 integrin in intracellular signaling pathways in human conjunctival epithelial cells adherent to laminin. In addition, the purpose was to compare the phosphorylation kinetics of signaling intermediates in cells adherent to different laminin isoforms. Cell adhesion assays, integrin clustering experiments, and integrin function blocking experiments demonstrated that beta1 but not beta4 integrin mediated human conjunctival epithelial cell adhesion to placental laminin isoforms (laminin-10/11) and induced focal adhesion kinase (FAK) tyrosine phosphorylation. Western blot analysis of cell lysates adherent to placental laminin showed that the tyrosine phosphorylation of p130Cas and FAK was maximally above constitutive levels after 60 min. In cells adherent to EHS laminin (laminin-1), the tyrosine phosphorylation kinetics of tensin, p130Cas, FAK and unknown proteins of 138 kDa and 110 kDa were similar, and peaked above constitutive levels after 30 min. Tyrosine phosphorylation of a 70 kDa protein was induced by cell adhesion to EHS laminin after 5 min, and phosphorylation peaked at 15 min. In contrast, the tyrosine phosphorylation of the 70 kDa protein was undetected in cells adherent to placental laminin. Erk-1 phosphorylation and activation was not differentially modulated by conjunctival epithelial cell adhesion to laminins. However, phosphorylation and activation kinetics of Erk-2 in cells adherent to placental laminin was similar to that observed for FAK and p130Cas. Erk-2 phosphorylation and activation was essentially undetectable in cells adherent to EHS laminin. These observations suggest that human conjunctival epithelial cell adhesion to different laminin isoforms activates different intracellular signaling pathways, and provides support for the hypothesis that extracellular matrix molecules can modulate ocular surface epithelial cell differentiation via alternate signaling pathways.


Subject(s)
Cell Communication/physiology , Conjunctiva/cytology , Epithelial Cells/physiology , Laminin/physiology , Antibodies, Monoclonal , Blotting, Western , Cell Adhesion , Cells, Cultured , Humans , Integrin beta1/physiology , Laminin/analogs & derivatives , Laminin/analysis , Phosphorylation , Placenta/chemistry , Time Factors , Tyrosine/physiology
13.
Dev Med Child Neurol ; 42(6): 364-7, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10875520

ABSTRACT

Sixty-nine very-low-birthweight infants out of a population of 923 had cerebral palsy (CP) at an 18-month follow-up. Thirty-nine of these had cranial ultrasound abnormalities in the neonatal period and 30 had normal cranial ultrasounds. The distribution of subtypes of CP differed markedly between the two groups, with hemiplegia predominating in those with abnormal cranial ultrasounds and diplegia in those with normal cranial ultrasounds. Regardless of ultrasound appearance, the relative risk of CP increased approximately fourfold with a neonatal history of sepsis.


Subject(s)
Cerebral Palsy/epidemiology , Infant, Premature, Diseases/epidemiology , Infant, Very Low Birth Weight , Sepsis/epidemiology , Brain Injuries/diagnostic imaging , Brain Injuries/epidemiology , Cerebral Hemorrhage/diagnostic imaging , Cerebral Palsy/diagnostic imaging , Comorbidity , Confidence Intervals , Developmental Disabilities/diagnostic imaging , Developmental Disabilities/epidemiology , Enterocolitis/epidemiology , Follow-Up Studies , Humans , Infant , Infant, Newborn , Infant, Premature, Diseases/diagnostic imaging , Meningitis/epidemiology , Odds Ratio , Paralysis/epidemiology , Retrospective Studies , Risk Factors , Sepsis/diagnostic imaging , Skull/diagnostic imaging , Skull/pathology , Twins/statistics & numerical data , Ultrasonography , United Kingdom/epidemiology
14.
Curr Eye Res ; 19(4): 293-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10520224

ABSTRACT

PURPOSE: To examine the ability of bovine corneal and conjunctival epithelial cells to adhere to different types of exogenous laminin preparations. METHODS: The ability of bovine corneal and conjunctival epithelial cells in primary culture to attach to laminin isolated from human placenta or from mouse EHS tumor was measured using a short-term colorimetric adhesion assay. Focal adhesion formation in response to interaction with laminins was determined by immunofluorescence microscopy using antibodies to vinculin and morphometric analysis. The influence of laminin on the secretion of adhesion complex proteins by bovine corneal epithelial cells in culture was analyzed using immunofluorescence microscopy. RESULTS: In short-term assays, primary bovine corneal epithelial cells demonstrate rapid and efficient adhesion to placental laminin, and significantly more cells contain focal adhesions, compared to those incubated on EHS laminin. In contrast, primary bovine conjunctival epithelial cells adhere equally well to placental and EHS laminin over a range of substrate concentrations. Additionally, the percentage of cells containing focal adhesions is not significantly different. In primary bovine corneal epithelium, the deposition of collagen type IV and collagen type VII into extracellular network-like structures is inhibited in cells cultured on placental laminin compared to cells cultured on EHS laminin. CONCLUSIONS: In vitro, bovine corneal epithelial cells attach more rapidly and efficiently to exogenous placental laminin compared to EHS laminin. However, this isoform inhibits the ready formation of adhesion complex-like structures in culture. The laminin isoform found in human placental preparations may therefore modulate corneal epithelial cell motility as opposed to permanent adhesion.


Subject(s)
Cell Adhesion , Conjunctiva/physiology , Cornea/physiology , Epithelial Cells/physiology , Laminin/metabolism , Animals , Cattle , Cells, Cultured , Conjunctiva/cytology , Cornea/cytology , Fluorescent Antibody Technique, Indirect , Microscopy, Fluorescence , Protein Isoforms , Vinculin/metabolism
15.
Biotech Histochem ; 74(3): 146-59, 1999 May.
Article in English | MEDLINE | ID: mdl-10416788

ABSTRACT

The cornea is a transparent and avascular tissue that functions as the major refractive structure for the eye. A wide variety of growth factors, chemokines, cytokines and their receptors are synthesized by corneal epithelial and stromal cells, and are found in tears. These molecules function in corneal wound healing and in inflammatory responses. Proteoglycans and glycoproteins are essential for normal corneal function, both at the air-epithelial interface and within the extracellular matrix. The ocular MUC mucins may play roles in forming the mucus layer of the tear film, in regulating tear film spread, and in inhibiting the adhesion of pathogens to the ocular surface. Lumican, keratocan and mimecan are the major keratan sulfate proteoglycans of the corneal stroma. They are essential, along with other proteoglycans and interfibrillar proteins, including collagens type VI and XII, for the maintenance of corneal transparency. Corneal epithelial cells interact with a specialized extracellular matrix structure, the basement membrane, composed of a specific subset of collagen type IV and laminin isoforms in addition to ubiquitous extracellular matrix molecules. Matrix metalloprotein-ases have been identified in normal corneal tissue and cells and may play a role in the development of ulcerative corneal diseases. Changes in extracellular matrix molecule localization and synthesis have been noted in other types of corneal diseases as well, including bullous keratopathy and keratoconus.


Subject(s)
Cornea/metabolism , Eye Proteins/physiology , Eye/pathology , Animals , Chemokines/metabolism , Chemokines/physiology , Cornea/cytology , Cytokines/metabolism , Cytokines/physiology , Extracellular Matrix/metabolism , Eye Proteins/metabolism , Glycoproteins/metabolism , Growth Substances/metabolism , Growth Substances/physiology , Humans , Proteoglycans/metabolism
16.
Eur J Pediatr ; 155(7): 576-9, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8831081

ABSTRACT

UNLABELLED: Antenatal steroid administration reduces mortality in preterm infants. We used logistic regression analysis to explore the influence of various factors on intact survival in a population of 798 very low birth weight infants admitted between 1985 and 1992. Antenatal steroid administration (n = 87) was associated with an improved chance of normal survival with an odds ratio of 3.0 (95% confidence intervals from 1.5 to 5.9). Other factors associated with improved outcome were a normal cranial ultrasound image or one showing subependymal haemorrhage, female sex, a 5 min Apgar score above 5, low inspired oxygen concentration and higher birth weight. Year of birth was not associated with a consistent trend to improve outcome over this period and surfactant administration rates were constant throughout. These results endorse the current recommendations to increase the use of antenatal steroid therapy. CONCLUSION: Antenatal steroid administration was associated with a threefold improvement in the chance of normal survival for very low birth weight infants as assessed at 18 months. These results suggest that the reduction in periventricular haemorrhage after antenatal steroid use is translated into a better longterm outcome.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Betamethasone/therapeutic use , Infant Mortality , Infant, Very Low Birth Weight , Prenatal Care , Female , Follow-Up Studies , Humans , Infant, Newborn , Logistic Models , Male , Odds Ratio , Pregnancy , Risk Factors , Survival Rate
17.
Arch Dis Child Fetal Neonatal Ed ; 71(3): F210-1, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7820719

ABSTRACT

Of 47 babies mechanically ventilated for more than 27 days for bronchopulmonary dysplasia 20 eventually died. There were no neurodevelopmentally intact survivors among those who were ventilated for more than 50 days. Days of ventilation more powerfully predicted outcome than ultrasound evidence of brain injury.


Subject(s)
Bronchopulmonary Dysplasia/therapy , Respiration, Artificial , Bronchopulmonary Dysplasia/mortality , Female , Humans , Infant , Infant, Low Birth Weight , Infant, Newborn , Male , Prognosis , Prospective Studies , Time Factors , Treatment Outcome
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