hCG beta expression by cervical squamous carcinoma--in vivo histological association with tumour invasion and apoptosis.

AIMS: To investigate the correlation of beta-subunit of human chorionic gonadotrophin (hCG beta) expression by cervical carcinomas with measures of tumour apoptosis. METHODS AND RESULTS: Eighty-nine cervical carcinoma patients' samples were subject to hCG beta immunohistochemistry and scored with respect to intensity of immunopositivity and percentage of positive cells. Apoptosis was evaluated by three independent parameters: morphological characteristics [haematoxylin and eosin (H&E)], terminal deoxynucleotidyl transferase biotin-dUTP nick end labelling (TUNEL) and poly (ADP-ribose) polymerase (PARP) immunopositivity. Of the 12 adenocarcinomas, only one (8%) was hCG beta+. However, 87% (61/70) of the squamous cell and 100% (7/7) of adenosquamous cell carcinomas were hCG beta+. hCG beta reactivity and intensity was predominantly confined to peripheral tumour cells at the stromal-epithelial interface. Correlation analysis showed that H&E and PARP apoptotic immunopositivity negatively correlated with hCG beta expression (P < 0.001 and P = 0.028 respectively), whereas TUNEL did not (P = 0.12). However, immunopositivity for apoptotic cells by TUNEL was significantly less in tumours where hCG beta expression was greater (scoring >or= 6) and vice versa. hCG beta immunopositivity was also observed in newly formed blood vessels, as well as tumour cells within lymphatic vessels. When tumour vascularization was taken into account, samples with noted vascularization positively correlated with hCG beta scoring. CONCLUSIONS: hCG beta expression correlates with reduced tumour cell apoptosis and may be involved in tumour vascularization and dissemination.

Granulosa cell survival and proliferation are altered in polycystic ovary syndrome.

CONTEXT: Polycystic ovary syndrome (PCOS) represents the most common endocrine abnormality in women of reproductive age. The cause of PCOS remains largely unknown, but studies suggest an intrinsic ovarian abnormality. OBJECTIVE: The objective of the study was to test our hypothesis that differences in granulosa cell proliferation and apoptosis may underlie abnormalities that affect follicular development. DESIGN: Granulosa cells were prepared from follicular fluid aspirated from 4- to 8-mm follicles of unstimulated ovaries during routine laparoscopy or laparotomy from women with anovulatory PCOS and those with regular ovulatory cycles. SETTING: The study was conducted at a university hospital. PATIENTS: Fourteen women with anovulatory PCOS and nine women with regular ovulatory cycles participated in the study. MAIN OUTCOME MEASURES: Immunocytochemistry on granulosa cells to investigate apoptotic and proliferation rates, together with real-time RT-PCR to analyze gene expression profiles of apoptotic regulators, was measured. RESULTS: Significantly lower apoptotic rates were found in granulosa cells from patients with PCOS, compared with women with regular ovulatory cycles (P=0.004). Lower apoptotic rates were associated with decreased levels of the apoptotic effector caspase-3 (P=0.001) and increased levels of the anti-apoptotic survival factor cellular inhibitor of apoptosis proteins-2 in the PCOS group that were coupled to higher proliferation rates (P=0.032). Gene expression profiling confirmed the immunocytochemical findings. CONCLUSIONS: Our findings indicate that there are significant differences in the rate of cell death and proliferation in granulosa cell populations in PCOS patients. These are associated with decreased expression of apoptotic effectors and increased expression of a cell survival factor. These results provide new insights that may be useful in developing specific therapeutic intervention strategies in PCOS.

Longitudinal muscle shows abnormal relaxation responses to nitric oxide and contains altered levels of NOS1 and elastin in uncomplicated diverticular disease.

OBJECTIVE: Recent evidence challenges the 'low-fibre/high-colonic intraluminal pressure' hypothesis of diverticular disease (DD) and raises the possibility that other mechanisms are involved. Although bowel wall smooth muscle is known to be hypercontractile in DD, the nature of its relaxation is unknown. The present study investigated colonic smooth muscle responses to nitric oxide, as well as the smooth muscle contents of neural nitric oxide and elastin associated with the disease. METHOD: Immunohistochemical/image analysis of antibodies to nitric oxide synthase (NOS1), co-localized with protein gene product (PGP) and to elastin, was performed on three histological sections of sigmoid colons from 20 patients (10 DD, 10 controls) following resections for rectal tumours. Organ bath experiments examined smooth muscle responsiveness to nitroprusside, a nitric oxide donor. RESULTS: Uncomplicated diverticular longitudinal muscle showed lower nitric oxide immunoreactivity compared with controls: median percentage surface area of NOS1 over PGP was 26.0% (range 0.5-58.3), controls 45.0% (35.0-70.1; P = 0.018). Median percentage surface area of elastin was elevated, 21.3% (10.6-45.6), controls 8.2% (1.7-13.5; P = 0.0002), together with a low sensitivity to nitroprusside [mean - log EC(50) 5.3 (SD 0.5), controls 6.6 (SD 0.5), difference 1.3, 95% CI 0.8-1.7; P < 0.0001] and there were lower maximum relaxation responses to nitroprusside compared with controls: median percentage (relaxation induced by nitroprussside/contraction induced by bethanecol) was 52.0%, range (20.0-92.0), controls 100.0% (71.0-125.0), P < 0.0001. No statistically significant differences were found in circular muscle, at the sample size studied. CONCLUSION: This study established, for the first time, specific abnormalities in longitudinal muscle relaxation and contents of neural nitric oxide and elastin in uncomplicated DD. These findings may have important implications for both colon structure and function in the disease.

Overexpression of the Axl tyrosine kinase receptor in cutaneous SCC-derived cell lines and tumours.

The molecular mechanisms that underlie the development of squamous cell skin cancers (SSC) are poorly understood. We have used oligonucleotide microarrays to compare the differences in cellular gene expression between a series of keratinocyte cell that mimic disease progression with the aim of identifying genes that may potentially contribute towards squamous cell carcinoma (SCC) progression in vivo, and in particular to identify markers that may serve as potential therapeutic targets for SCC treatment. Gene expression differences were corroborated by polymerase chain reaction and Western blotting. We identified Axl, a receptor tyrosine kinase with transforming potential that has also been shown to have a role in cell survival, adhesion and chemotaxis, was upregulated in vitro in SCC-derived cells compared to premalignant cells. Extending the investigation to tumour biopsies showed that the Axl protein was overexpressed in vivo in a series of SCCs.

LEKTI demonstrable by immunohistochemistry of the skin: a potential diagnostic skin test for Netherton syndrome.

BACKGROUND: Netherton syndrome (NS) is a rare autosomal recessive condition characterized by ichthyosiform erythroderma, trichorrhexis invaginata and atopic manifestations. Confirming the diagnosis may be difficult in the early stages. Mutations in the SPINK5 gene which encodes for the serine protease inhibitor LEKTI are associated with NS. These mutations create premature termination codons which result in absent or abnormal expression of LEKTI in patients with NS. OBJECTIVES: To investigate the expression of LEKTI in the skin of patients with NS in comparison with normal controls and patients with other skin conditions, namely atopic dermatitis, psoriasis and nonbullous ichthyosiform erythroderma. METHODS: Immunohistochemistry was performed on skin sections from four patients with NS, four normal controls, four with atopic dermatitis, two with psoriasis and two with nonbullous ichthyosiform erythroderma, using a primary rabbit polyclonal antibody against LEKTI. RESULTS: LEKTI was localized to the stratum granulosum in normal skin. All four skin sections from patients with NS showed absent or very reduced staining for LEKTI. Staining in the other disorders showed positive LEKTI expression in varying patterns. CONCLUSIONS: NS can be difficult to diagnose especially in the early stage, which can lead to inappropriate treatments particularly if it is misdiagnosed as atopic dermatitis. Immunohistochemistry of skin with an antibody against LEKTI is a potentially useful diagnostic test for NS.

Reduced apoptotic levels in squamous but not basal cell carcinomas correlates with detection of cutaneous human papillomavirus.

We have investigated the apoptotic levels and expression of the apoptotic inducer Bak in non-melanoma skin cancers. Squamous cell carcinomas of known human papillomavirus status from immunocompetent patients were analysed for the expression of the Bak protein, and the expression profile was compared both to the presence of apoptotic cells and the proliferation marker Ki-67. We demonstrate an inverse correlation between human papillomavirus positivity and Bak expression in squamous cell carcinomas, with concomitantly fewer apoptoic cells being detected in the human papillomavirus positive tumours. Bak expression was not observed in basal cell carcinomas irrespective of human papillomavirus status, suggesting that Bak only plays a role in signalling apoptosis in squamous, but not basal, cell cancers. No differences were observed in the proliferation rates between papillomavirus positive and negative squamous cell tumours. However, a significant decrease in the number of apoptotic cells was observed in human papillomavirus-positive squamous cell carcinomas which suggests that the virus may have significantly altered the relationship between proliferation and apoptosis in a proportion of these tumours.

Human beta defensin-1 and -2 expression in human pilosebaceous units: upregulation in acne vulgaris lesions.

A rich residential microflora is harboured by the distal outer root sheath of the hair follicle and the hair canal - normally without causing skin diseases. Although the basic mechanisms involved in the development of inflammation during acne vulgaris remain unclear, microbial agents might play an important role in this process. In this study we have analyzed by in situ hybridization and immunohistochemistry the expression patterns of two antimicrobial peptides, human beta defensin-1 and human beta defensin-2, in healthy human hair follicles as well as in perilesional and intralesional skin of acne vulgaris lesions such as comedones, papules, and pustules. Strong defensin-1 and defensin-2 immunoreactivity was found in all suprabasal layers of the epidermis, the distal outer root sheath of the hair follicle, and the pilosebaceous duct. Marked defensin-1 and defensin-2 immunoreactivity was also found in the sebaceous gland and in the basal layer of the central outer root sheath including the bulge region. The majority of acne biopsies displayed a marked upregulation of defensin-2 immunoreactivity in the lesional and perilesional epithelium - in particular in pustules - and a less marked upregulation of defensin-1 immunoreactivity. The upregulation of beta-defensin expression in acne vulgaris lesions compared to controls suggests that beta-defensins may be involved in the pathogenesis of acne vulgaris.

An association between sebaceous carcinoma and microsatellite instability in immunosuppressed organ transplant recipients.

Sebaceous carcinomas are rare cutaneous appendageal tumors that may occur sporadically or in association with an internal malignancy in Muir-Torre syndrome. In Muir-Torre syndrome microsatellite instability can often be demonstrated in tumor DNA as a result of an inherited mutation in one of several known mismatch repair genes; however, the role of microsatellite instability in sporadic sebaceous carcinomas has not been previously studied. In this report we describe the clinicopathologic characteristics of a series of unselected sebaceous carcinomas and examine them for the presence of microsatellite instability. Of 10 consecutive tumors identified over a 10 y period, only one was from a patient known to have Muir-Torre syndrome. Of the nine presumed sporadic cases, five were from four renal transplant recipients and four from otherwise healthy individuals. Microsatellite instability was demonstrable in three cases: in the Muir-Torre syndrome-associated tumor and in two tumors from transplant patients. Microsatellite instability was subsequently also found in a sebaceous carcinoma from a further transplant patient prospectively sought from another institution. The presence of microsatellite instability in post-transplant sebaceous carcinomas was associated with loss of expression of the mismatch repair protein hMSH2. In summary, sebaceous gland carcinomas, while characteristic of Muir-Torre syndrome, are commonly found outside this context. Among presumed sporadic cases, our data suggest they may be over-represented in immunosuppressed renal transplant recipients. The presence of microsatellite instability in transplant-associated lesions, together with loss of hMSH2 expression suggests that immunosuppression might unmask a previously silent Muir-Torre syndrome phenotype in some cases. Alternatively, there is experimental evidence to suggest that immunosuppressive drugs, most plausibly azathioprine, could select for the emergence of a mutator phenotype and thus predispose to the development of sebaceous carcinomas. The role of mismatch repair defects in other post-transplant skin malignancies remains to be established.

Laser modulation of angiogenic factor production by T-lymphocytes.

BACKGROUND AND OBJECTIVE: In previous investigations, small variations in the energy densities of low level light therapy (LLLT) were found to produce significant differences in the proliferation of resting T-lymphocytes in vitro. Pulsing these cells with mitogen in addition to laser therapy produced inhibitory effects regardless of the amplitude of the energy density used. In the current study, the effect of LLLT on the production of angiogenic factor(s) by T-lymphocytes was investigated in vitro. STUDY DESIGN/MATERIALS AND METHODS: Human T-cells isolated from peripheral blood were prepared in suspension either with or without addition of mitogen. Cell suspensions were irradiated with laser by using the following energy densities: 1.2, 3.6, 6.0, and 8.4 J/cm(2). Wavelength, pulsing frequency, and power output were kept constant at 820 nm, 5,000 Hz, and 50 mW, respectively. After either 3 or 5 days of incubation, lymphocyte supernatants were collected and added as conditioned media to cultured endothelial cells (ECs). The effect on the proliferation of these ECs was assessed over a 72-hour period by using a methylene blue assay. RESULTS: Endothelial cell proliferation increased significantly when incubated with conditioned media collected from resting T-cells exposed to 1.2 and 3.6 J/cm(2). Day 5 conditioned media produced similar patterns of EC proliferation to that of day 3 but at lower magnitude. Pulsing of T-lymphocytes with mitogen in addition to laser irradiation significantly lessened their angiogenic capability. Conditioned media from 3.6 J/cm(2) laser-treated T-cells induced the maximal EC proliferation in all groups studied. CONCLUSION: It would seem that laser therapy stimulates lymphocytes to produce factor(s) that can modulate EC proliferation in vitro; this effect on the lymphocytes is influenced by (1) the amplitude of energy density used for T-cell irradiation, (2) exposing T-cells to both mitogen and laser, and (3) the duration of T-cell incubation in culture.

Gli1 protein is expressed in basal cell carcinomas, outer root sheath keratinocytes and a subpopulation of mesenchymal cells in normal human skin.

Genetic studies of patients with the nevoid basal cell carcinoma syndrome have led to the recognition of the importance of the hedgehog signaling pathway in the development of basal cell carcinomas of the skin. Although hedgehog signaling is known to be important in hair follicle development, the function of this pathway in adult skin and the mechanism by which activation of this pathway leads to basal cell carcinoma development remain to be established. The Gli1 family of transcription factors mediates hedgehog signaling in mammalian cells and we have shown in previous studies that Gli1 mRNA is differentially expressed in basal cell carcinomas. Using antibodies to epitopes on the N and C terminal regions of Gli1 we show now that Gli1 protein is present in basal cell carcinomas and that the protein is mainly localized to the cytoplasmic compartment. Focal nuclear staining was seen in a small number of basal cell carcinomas with the C terminal antibody which suggest that nuclear localization is not dependent on loss of the C terminus of Gli1 due to proteolysis. Strong Gli1 immunostaining was seen in the outer root sheath keratinocytes of some hair follicles, a subpopulation of mesenchymal cells in the vicinity of the bulge region of adult hair follicles and the dermal sheath cells of developing hair follicles. Quantitation of Gli1 mRNA in basal cell carcinomas using northern blot analysis indicates that Gli1 is highly expressed in basal cell carcinomas. This suggests that the lower intensity of Gli1 immunostaining in basal cell carcinoma islands relative to outer root sheath keratinocytes is not simply a reflection of differences in gene expression. The continued expression of Gli1 in adult hair follicles and in the mesenchyme of adult human skin suggest that Hh signaling may play a part in hair cycling and in epidermal mesenchymal interactions important in normal skin maintenance.

[Prevalence of hemoglobin abnormalities in Kebili (Tunisian South)]. / Prévalence des anomalies de l'hémoglobine à Kebili (sud Tunisien).

BACKGROUND: Hemoglobin abnormalities constitute a public health problem in many countries in the world. In Tunisia, these disorders were thought to affect only the North-western population. However, the existence of hemoglobinosis concentration in Kebily in south Tunisia has been suggested by previous work. In order to estimate their frequencies, we performed a screening of hemoglobin abnormalities in the North-Kebili region, to establish a prevention program of the homozygous forms. METHODS: This screening concerned all 1st and 2nd grade primary school pupils in North Kebily. After a questionnaire, a blood sample was drawn from every child. Hemogram, sickling test, and hemoglobin electrophoresis at alkaline pH were performed for all children. Hemoglobin electrophoresis at acid pH and a specific hemoglobin A2 titration were performed for some children. RESULTS: The study concerned 1,400 children, aged between 5 and 12 years, the mean age was 7 years and 7 months +/- 10 months. Consanguinity rate and coefficient were respectively 44% and 2249 x 10(5). Endogamy was very high. The global rate of hemoglobin abnormalities was 9.4%. Drepanocytosis with a rate of 4.9% was the most frequent, followed by beta thalassemia (3.1%) and C hemoglobinosis (1.6%). These abnormalities were unequally distributed; very frequent in some localities, they were quite absent in others. CONCLUSIONS: This study revealed a hemoglobinosis concentration in Tunisia, which can be classified second after that of Beja in North-western Tunisia. The heterogeneous distribution of the hemoglobin abnormalities in North-Kebili region and the high consanguinity and endogamy rates constitute factors that promote homozygous and double heterozygous forms to arise and justify the elaboration of a preventive strategy.

[Hemoglobin beta S haplotype in the Kebili region (southern Tunisia)]. / Etude de l'haplotype beta S de l'hémoglobine dans la région de Kebili (Sud tunisien).

Sickle cell anemia is a monogenic hereditary disease characterized by a mutation in the beta globin gene. Five major haplotypes associated with the beta S mutation have been defined: Benin, Bantu, Senegalian, Camerounian, and Arabo-Indian. Previous studies in northern Tunisia showed that sickle cell anemia was of Benin origin in this region. Patients from the south of Tunisia, mainly from the Kebili region, were not previously concerned. In this study, we have determined the beta S haplotype and evaluated phenotypical expression of the disease in 14 patients from this latter region. The use of four restriction endonucleases having polymorphic sites in the beta globin gene showed that all patients had the Benin haplotype, confirming the Benin origin of sickle cell anemia in Tunisia. This haplotype is associated with an heterogeneous expression of fetal hemoglobin (HbF) with extremes varying from 2.4 to 16.3% and a mean expression rate of 8.16%, which is in accordance with literature data. In spite of the haplotype homogeneity in our patients, clinical heterogeneity was noted. A unique case of alpha-thalassemia could not explain this heterogeneity. In contrast, we found a certain correlation between fetal hemoglobin expression and clinical severity.

The direct effect of light therapy on endothelial cell proliferation in vitro.

During repair, new blood vessels are formed by the process of angiogenesis. The prerequisite to blood vessel formation is the proliferation of endothelial cells. The purpose of this study was to find out if light therapy is capable of affecting endothelial cell proliferation in vitro. The direct effect of light at wavelengths of either 660 or 820 nm was studied on primary cultures of bovine aortic endothelial cells using varying energy densities, of either 1, 2, 4, or 8 J/cm2. The proliferation of the endothelial cells was assessed over a period of five days after a single irradiation.

Visibility distance of highway signs among young, middle-aged, and older observers: icons are better than text.

The visibility distances for young, middle-aged, and elderly observers of text and icon versions of four different highway signs were compared under day and dusk lighting conditions. No age differences were observed. Icon signs, however, were visible at much greater distances than were text signs for all three age groups, a difference that was more pronounced under dusk conditions. There were no age differences in the comprehension of icon signs, but there was considerable variability from one icon sign to another in the degree to which they were comprehended. Acuity was found to be a better predictor of the visibility distance of text signs in both day and dusk conditions than it was of icon signs. To the degree that they are comprehended, icon signs appear to offer drivers of all ages almost twice as much time in which to respond to them.