Metaplastic Squamous Epithelium Research Articles

Congenital Solitary Liver Cysts

The aim of the study was to describe clinical and pathological findings in children with rare congenital solitary liver cyst. Six children with congenital liver cyst were treated at the authors' institution from 1995 to 2002. Clinical records and operative findings of these patients were reviewed retrospectively. Age at presentation ranged from neonatal to 14 years, and there were four girls and two boys. Hepatomegaly was the most common symptom in neonates while the older children presented with abdominal pain. Ultrasound was conclusive for diagnosis in all children, prenatal ultrasound in three. Intrahepatic cyst was found in five children. Partially extrahepatic cyst in the porta hepatis was found in one. The cyst diameters varied from 8 to 10 cm. Cysts were excised via an open abdominal approach in all patients. Histological findings confirmed the diagnosis of congenital liver cyst. Columnar epithelium was found in newborns while atrophic changes of epithelial lining were seen in older children. In a case of a 13-year-old girl the cyst was lined by metaplastic squamous epithelium with foci of slight dysplasia. Immunohistochemical studies were available in three recent children with positive findings in all of them. The postoperative course was uneventful in all patients. The follow-up period ranged from 36-120 months and no recurrence was observed. With appropriate selection of symptomatic patients, total excision of a congenital liver cyst is a safe procedure with excellent long-term results. Given the possibility of malignant degeneration of a congenital liver cyst we recommend its surgical excision in most cases.

Diminished expression of multidrug resistance-associated protein 1 (MRP1) in bronchial epithelium of COPD patients

Cigarette smoke is the principal risk factor for chronic obstructive pulmonary disease (COPD). Multidrug resistance proteins, such as multidrug resistance-associated protein-1 (MRP1), P-glycoprotein (P-gp), and lung resistance-related protein (LRP), may protect against oxidative stress and toxic compounds generated by cigarette smoking. Expression of MRP1, P-gp, and LRP was evaluated in bronchial epithelium of two study groups of COPD patients and their controls and was associated with disease status and smoking history. In study group 1, MRP1, but not P-gp and LRP expression, was lower (p=0.029) in normal bronchial epithelium of COPD patients (n=11) compared to healthy controls (n=8). MRP1 expression was high in squamous metaplastic epithelium. When including expression in squamous metaplastic cells, MRP1 was still lower in total bronchial epithelium in the COPD group (p=0.038). In study group 2, expression of MRP1, but not of P-gp and LRP, was lower (p=0.047) in lung tissue of (very) severe COPD (n=10) vs mild to moderate COPD (n=9) patients. In conclusion, MRP1 expression was lower in bronchial biopsies of COPD patients than of healthy controls and was also lower in patients with severe COPD than with mild/moderate COPD. Our findings indicate that diminished MRP1 expression in normal bronchial epithelium is associated with COPD. The exact role in COPD pathogenesis is to be revealed by further functional studies.

Light and Electron Microscopic Study of Primary Atrophic Rhinitis Mucosa

This study examined the light and the electron microscopic changes in the mucosa of primary atrophic rhinitis and compared them with the normal nasal mucosa to establish the changes in the surfactant system. A prospective original study was performed. Twenty cases of primary atrophic rhinitis were randomly selected in the outpatient clinic of Sohag University Ear, Nose, and Throat Department. Ten volunteers with no history of chronic nasal disease and with normal rhinopharyngeal picture were selected as control cases. A small punch biopsy was performed with a small forceps under local anesthesia from the medial edge of the inferior turbinate. After histological laboratory preparations, semithin sections (0.5-1 microm) were prepared by using an LKB ultramicrotome. The sections were stained by toluidine blue, examined by light microscope, and photographed. Ultrathin sections (500-800) from selected areas of the trimmed blocks were made and collected on copper grids. The ultrathin sections were then contrasted in uranyl acetate for 10 minutes and examined by electron microscope Jeol JEM-1010. Light microscopy of primary atrophic epithelium revealed typical nonkeratinized stratified squamous epithelium to keratinized squamous epithelium with a thin layer of keratin on the surface. Well-developed desmosomes appeared between the epithelial cells. In the lamina propria, no submucosal glands could be seen. Electron microscopy of it revealed that the stratification of the epithelium increased. Sloughing of the superficial cells was observed in some regions of the proliferating epithelium. Epithelial penetration with neutrophils (mainly) and lymphocytes (some) could be seen. No numerous multilamellar bodies (MLBs) could be detected in these cases. An increased amount of collagenous fibers was observed in the basement membrane. In primary atrophic rhinitis, the epithelial cells revealed that desmosomes are characteristic of the metaplastic squamous epithelium and had no MLB in their cytoplasm, and cells in which occasional MLBs had been established showed interdigitations between them and the surrounding cells, suggesting an association between the surfactant deficiency and the development of desmosomes.

Cytokeratin18, 13 and their gene expression in post-operative maxillary cyst linings with metaplastic epithelium

To study the cytokeratin 18 and 13 and their gene (CK) expression in post-operation maxillary cyst linings with metaplastic epithelium. CK expressions were examined with immunohistochemistry in 46 post-operative maxillary cyst (POMC) which were lined with pseudostriated columnar cells only (13 cases), both kinds of columnar and squamous cells (30 cases) and squamous cells only (3 cases). The expressions of CK8, CK13 and CK18 were observed in 39, 9 and all of the 43 columnar epithelial linings, respectively. Metaplastic squamous epithelia expressed more CK13 and less CK18 and CK8. Of the 33 metaplastic linings, 24 expressed CK8, 23 CK13 and 26 linings expressed CK18. The expression of CK13- and CK18-mRNA was generally correlated with the protein expression level. By in situ hybridization, CK18-mRNA expression was observed not only in 26 metaplastic linings which were positive for CK18 protein but also in five of the seven metaplastic linings which did not express CK18 protein. In addition, RT-PCR revealed an expression of CK18-mRNA in all metaplastic squamous linings although the expression level was weaker than that in the columnar epithelial linings. The CK13-mRNA was expressed in a fashion inverse to the CK18-mRNA. These results indicate that CK18-mRNA is preserved through metaplasia although the protein expression decreases and metaplastic squamous cells differentiate with a decrease of CK18 and an increase of CK13 expression.

Histological changes in rat nasal epithelia after unilateral neonatal naris occlusion

The authors studied the extent of the different epithelia lining the nasal fossae of the albino rat after neonatal closure of one naris. Newborn pups were anesthetized by hypothermia and the external opening of their right naris cauterized, while littermates served as controls. Animals were sacrificed at 3 months, and the occluded (OCF) and nonoccluded (NOF) fossae of experimental animals as well as both fossae of control animals (CTF) were histologically studied. In both control and experimental animals, nasal fossae were lined by five different types of epithelia: squamous stratified, transitional, metaplastic, respiratory, and olfactory epithelia. It was found that closure of one naris provokes reorganization of the epithelial lining in both the occluded and nonoccluded side. In CTF airflow, physical conditions as well as pollutants and biological agents irritate the epithelial lining, causing squamous metaplasia as well as metaplastic epithelium showing inflammation in rostral levels. In CTF caudal levels, the metaplastic epithelium appears to a lesser degree and the respiratory epithelium prevails, except for the most caudal level where the olfactory epithelium is prevalent. In OCF, the protected environment created prevents the occurrence of metaplastic epithelium, the transitional, respiratory, and olfactory epithelia developing in the corresponding area instead. In NOF, where the airflow is double, the same pattern occurs as in CTF, although metaplastic epithelium values are approximately double, suggesting a clear linear effect. An outstanding feature observed was the increased extent of the olfactory epithelium in OCF regarding NOF, although changes in its morphological structure were not found. Airflow properties, including pressure, coldness, velocity, and turbulence, as well as biological and chemical hazards present in inflow, cause histological reorganization of the nasal epithelium lining during postnatal development. Results prove the need to consider airflow changes in nasal fossae surgery and point to the protective value of naris closure in ENT clinics, supporting it as a treatment of atrophic rhinitis.

Immunohistochemical detection of GLUT1, p63 and phosphorylated histone H1 in head and neck squamous intraepithelial neoplasia: evidence for aberrations in hypoxia‐related, cell cycle‐ and stem‐cell‐regulatory pathways

Most epithelial malignancies are characterized by multistep progression from preinvasive/intraepithelial neoplasia to invasive malignancy. Detection and grading of early squamous intraepithelial neoplasia may at times be problematic. The aim of this study was to examine the ability of immunomarkers GLUT1, phospho-histone H1 and p63 to detect such early lesions. Sections of formalin-fixed paraffin-embedded tissue from 27 cases of squamous intraepithelial neoplasia, 26 associated with invasive carcinoma, were immunostained with anti-p63 (4A4; Santa Cruz), anti-GLUT1 (Chemicon) and anti-phospho-histone H1 (monoclonal 12D11) and compared with normal, hyperplastic and immature squamous metaplastic epithelium. Normal epithelium displayed phospho-histone H1 in scattered parabasal cells; p63 in the basal one-quarter to one-half of epithelium; and GLUT1 negativity or weak/equivocal mid-epithelial GLUT1+ foci. In hyperplasia phospho-histone H1+ cells were also limited to the parabasal layer; p63 positivity was essentially identical to that in normal epithelium; GLUT1 characteristically stained basal cells in rete-like areas. p63 staining in squamous intraepithelial neoplasia (grade 1) was indistinguishable from normal epithelial staining; in contrast, squamous intraepithelial neoplasia (grade 3) was readily apparent, with up to full-thickness p63 positivity. Squamous intraepithelial neoplasia (grade 1) was readily distinguishable from normal epithelium with both phospho-histone H1 and GLUT1 immunostaining; both markers were detected in cell layers above the parabasal layer. With both, progressively higher cell layers stained in proportion to the severity of the intraepithelial neoplasia, up to full thickness positivity in grade 3 squamous intraepithelial neoplasia. Squamous metaplasia and grade 3 squamous intraepithelial neoplasia were not distinguishable with p63 (both showed full-thickness staining) but were readily distinguishable with GLUT1 and phospho-histone H1 stains. GLUT1 appeared to be the most sensitive marker for all grades of intraepithelial neoplasia. Altered expression of all three markers was a common finding in squamous intraepithelial neoplasia, hence, dysregulation of cell cycle-promoting cyclin-dependent kinases (phospho-histone H1), altered stem cell regulatory pathways (p63) and enhancement of hypoxia-sensing pathways (GLUT1) are all early alterations in the progression of squamous malignancy of head and neck origin. A panel of all three may be a useful means of detecting squamous intraepithelial neoplasia.

Hyper-elevated prostate-specific antigen levels are not always carcinoma

An 81-year-old man with a past history of diabetes, hypertension, ischaemic heart disease and cerebrovascular disease was admitted to hospital with hypotension and bradycardic collapse. Owing to persistent hypotension and a low urine output, an indwelling catheter (IDC) was inserted per urethra and a cardiac pacemaker was placed the following day. A serum prostate-specific antigen (PSA) level was back-ordered on initial bloods taken before IDC insertion, as passing the catheter was difficult and he was noted to have an enlarged prostate. A trial of void without catheter was successful 24 hours after initial insertion, leading to discharge that evening He represented to the emergency department in acute urinary retention the day following discharge and gave no past history of significant lower urinary tract symptoms. An IDC was again inserted draining 700 ml and notes were obtained from his previous admission indicating that he had a PSA of 933 ng/ml (Immulite 2000, Diagnostic Products Corporation, Los Angeles, USA) on admission. The plan was for staging of prostate cancer and needle biopsy in the future to confirm the diagnosis. On examination, his prostate was enlarged and firm with no obvious nodular change. A bone scan was negative for metastatic prostate cancer. Prostatic needle biopsies (18 gauge) were undertaken revealing benign glands and also the edge of coagulative necrosis (Figure 1). The necrosis involved both stroma and glands, and was surrounded by a zone of immature fibrous tissue containing nests of metaplastic squamous epithelium (Figure 2). Findings were consistent with prostatic infarction and there was no evidence of malignancy. A repeat serum PSA demonstrated a rapid descent to 9.3 ng/ml. The patient was discharged after a successful trial of void and is now catheter free.

Expression of Epidermal Growth Factors and Their Receptors in the Bronchial Epithelium of Subjects With Chronic Obstructive Pulmonary Disease

Smoking may affect epithelial repair and differentiation differentially in smokers with and without chronic obstructive pulmonary disease (COPD). We hypothesized that epithelial repair is disturbed in patients with COPD owing to higher expression of epidermal growth factor (EGF)-like factors and/or receptors. We studied epithelial expression of EGF, transforming growth factor a, amphiregulin, heregulin (HRG), betacellulin (BTC), and their receptors, EGFR, HER-2, and HER-3, by immunohistochemical analysis in resected bronchial tissue from 20 subjects with (forced expiratory volume in 1 second [FEV(1)] <75% of predicted value) and 18 without (FEV(1) >85% predicted value) COPD. All subjects underwent surgery for lung cancer. The proportion of intact, damaged, goblet, or squamous metaplastic epithelium was similar in subjects with and without COPD. Regardless of smoking status, HRG expression was higher in intact epithelium of patients with COPD than in those without. Subgroup analysis showed higher EGFR expression in intact epithelium (1.4 times; P pound .04) and higher EGF, BTC, and HRG expression in damaged epithelium (1.4-1.8 times; P<or=.05) of ex-smokers with COPD compared with ex-smokers without COPD. These data support our hypothesis and suggest that current smoking obscures intrinsically higher expression in COPD.

P16 Expression in the Female Genital Tract and Its Value in Diagnosis

p16 is a cyclin-dependent kinase-4 inhibitor that is expressed in a limited range of normal tissues and tumors. In recent years, immunohistochemistry with p16 antibodies has been used as a diagnostic aid in various scenarios in gynecologic pathology. Diffuse (as opposed to focal) positivity with p16 in the cervix can be regarded as a surrogate marker of the presence of high-risk human papillomavirus (HPV). In cervical squamous lesions, p16 is positive in most high-grade cervical intraepithelial neoplasia (CIN) and in some cases of low-grade CIN, usually those associated with high-risk HPV. p16 may be useful to identify small focal high-grade CIN lesions, to distinguish some cases of CIN involving immature metaplastic squamous epithelium from immature metaplastic squamous epithelium not involved by CIN and to distinguish high-grade CIN from benign mimics. Most cervical carcinomas of squamous, glandular, and small cell type are p16-positive. In cervical glandular lesions, p16 is useful, as part of a panel, in the distinction between adenocarcinoma in situ (diffusely positive) and benign mimics, including tuboendometrial metaplasia and endometriosis, which are usually p16-negative or focally positive. p16 may be used, in combination with other markers, to distinguish between a cervical adenocarcinoma (diffuse positivity) and an endometrioid-type endometrial adenocarcinoma (negative or focally positive). Some uterine serous carcinomas are diffusely positive. In the vulva, p16 is positive in HPV-associated vulval intraepithelial neoplasia (VIN) but negative in VIN not associated with HPV. Similarly, HPV-associated invasive squamous carcinomas are p16-positive, whereas the more common non-HPV-associated neoplasms are largely negative or focally positive. In the uterus, p16 positivity is more common and widespread in leiomyosarcomas than leiomyomas, and this may be a useful aid to diagnosis, although problematic uterine smooth muscle neoplasms have not been extensively studied. Metastatic cervical adenocarcinomas in the ovary are usually diffusely p16-positive, and because these may closely mimic a primary ovarian endometrioid or mucinous adenocarcinoma, this may be a valuable diagnostic aid, although p16 expression in primary ovarian adenocarcinomas of these morphologic subtypes has not been widely investigated. Some ovarian serous carcinomas, similar to their uterine counterparts, are p16-positive.

Should All Asymptomatic Endocervical Polyps Be Removed: Two Case Reports

Endocervical polyps are benign, pedunculated growths from the cervix. They are usually an incidental finding on examination of the cervix, though sometimes they can cause intermenstrual or postcoital bleeding. We present two case reports of asymptomatic endocervical polyps. In the first case, the endocervical polyp was noted in the colposcopy clinic. The woman had been referred with a mild dyskaryotic smear. Histology of the polyp showed CIN 2 and 3. In the second case, the polyp showed severe dysplasia. Hysteroscopy was performed to rule out endometrial carcinoma. CIN 3 can progress to invasive cancer in 12 % of cases. Atypical endometrial hyperplasia is an ominous finding on histology. 10-20% of all cases with atypia will have an underlying carcinoma. Invasive cancer develops in up to 50% of cases. As far as we are aware, these are the first case reports of CIN 3 and severe dysplasia reported in endocervical polyps. We recommend that all asymptomatic endocervical polyps be removed and sent for histological examination. CASE REPORT 1 A 46 year old, P0+0, was referred to the colposcopy clinic with a mildly dyskaryotic smear. She had no intermenstrual or postcoital bleeding or any other symptoms. She had regular menstrual cycles. She was on the combined contraceptive pill. She had no significant past medical or surgical history and was a non-smoker. On colposcopy, the entire squamocolumnar junction was seen. Colposcopy was complete with a type 1, small transformation zone. There were no acetowhite or iodine negative areas. There was a small 1 cm by 1 cm long endocervical polyp, which was removed and sent for histology. Histology of the polyp showed extensive squamous metaplasia. Squamous epithelium on the surface and the lining crypts showed cytological atypia indicating CIN 2 and focal CIN 3. The patient was recalled to the colposcopy clinic. She had a large loop excision of the transformation zone (LLETZ) under local anaesthetic. The histology of the loop specimen showed CIN 3 with complete excision. CASE REPORT 2 A 57-year-old woman, P2+0, was referred by to the gynaecology clinic with an endocervical polyp. The polyp had been noted by her GP while taking a routine cervical smear. She had no symptoms. She was postmenopausal with no significant past medical or surgical history. She was not on HRT. The polyp was removed in the gynaecology outpatient clinic and sent for histological examination. Histology reported the polyp as an endometrial polyp in which a few glands showed severe dysplasia with severe cytological atypia. The patient was recalled to the clinic. She had a hysteroscopy examination, which showed multiple endometrial polyps. The polyps were removed. Histology showed benign endometrial polyps. DISCUSSION Endocervical polyps are small, pedunculated growths of the endocervix. It is the most common cervical growth especially in the multigravids. It is usually asymptomatic and found incidentally. Occasionally the polyp may cause Should All Asymptomatic Endocervical Polyps Be Removed: Two Case Reports 2 of 3 intermenstrual, postcoital or postmenopausal bleeding. On histology, the polyp is characterised by overgrowth of benign stroma covered by epithelium. Endocervical polyps are covered by endocervical, squamocolumnar or squamous metaplastic epithelium. The clinical behaviour is essentially benign. In the first case, the histology of the endocervical polyp showed CIN 2 to CIN 3. The colposcopy was normal and did not show any acetowhite changes. The UK guidelines for colposcopy suggest a colposcopy and punch biopsy for mild dyskaryosis but a ‘see and treat' policy for higher-grade abnormal cervical smears.1 CIN 3 can progress to invasive cancer in 12 % of cases. Regression rates without treatment are only 32% and persistence rates about 56%.2 The CIN 3 would have been missed had the polyp not been removed. In the second case, histology of the endocervical polyp was reported as an endometrial polyp with severe dysplasia with atypia. Atypical endometrial hyperplasia is an ominous finding on histology. 10-20% of all cases with atypia will have an underlying carcinoma. Invasive cancer develops in up to 50% of cases.3 Hysteroscopy was performed to rule out adenocarcinoma. Hysteroscopy showed presence of multiple, benign endometrial polyps. We recommend that all asymptomatic endocervical polyps should be removed and sent for histological examination.

Study of Epstein-Barr Virus infection in Nasopharyngeal Morphological Carcinogenesis

目的 探讨EB病毒在鼻咽癌形态发生学的哪一阶段进入鼻咽上皮细胞.方法从3212例鼻咽癌活检组织切片中筛选并收集到具有各种癌旁上皮病变的鼻咽癌标本85例,用核酸原位杂交法检测癌旁上皮病变中EB病毒编码的小RNAs(EBERs)感染,其中31例具有癌旁鳞状化生病变的鼻咽癌组织进一步用核酸原位杂交法检测EB病毒溶解期产物EA-D(earlyantigen-diffuse)mRNA.结果85例鼻咽癌标本共观察到154个癌旁上皮病变病灶:39个柱状上皮单纯增生灶、43个化生鳞状上皮增生灶、41个上皮异型性变(轻度、中度和重度)灶、17个原位癌灶及14个微小浸润癌灶.所有癌旁正常或单纯增生的柱状上皮、化生鳞状上皮均显示EBERs阴性.一部分(11/41,26.83%)癌旁异型性变上皮中的少数细胞表达EBERs,大部分原位癌(12/17,70.59%)及全部微小浸润癌都显示相当数量的EBERs阳性癌细胞.31例可见癌旁鳞状化生上皮病变的鼻咽癌中有10例癌旁上皮角化细胞的细胞核上显示出EA-DmRNA阳性信号.结论EB病毒可以首先感染异型性变的上皮细胞,然后可能与其他致癌产物协同对鼻咽癌变过程起了重要的作用.此外,从鼻咽癌细胞中释出的EB病毒可以重复感染癌旁鳞状化生上皮内的角化细胞,这种溶解性感染不具有重要的病理学意义。

P63 expression in assessment of bronchioloalveolar proliferations of the lung

Discrimination of well-differentiated pulmonary adenocarcinoma from reactive bronchioloalveolar epithelium can be difficult on routine histology, especially with small biopsies. Ancillary studies to help in this distinction are desirable. p63, a p53-homologous nuclear protein, is a marker of reserve cells of the bronchus and terminal lobular unit. In this study, 33 cases of adenocarcinoma (20 open lung and 13 transbronchial/percutaneous biopsies) and 43 cases of benign lungs with fibrosis and metaplasia (22 open lung and 21 transbronchial/percutaneous biopsies) were studied for nuclear p63 expression by immunohistochemistry (Dako, Carpinteria, CA, USA). Five additional cases each of atypical adenomatous hyperplasia and adenosquamous carcinoma and three cases of squamous carcinoma (all open lung biopsies) were also stained. The diagnostic categories of benign lung conditions were usual interstitial pneumonia, parenchymal scar, cryptogenic organizing pneumonia and diffuse alveolar damage. In neoplastic cases, p63 positivity was calculated as percentage of all tumor cells examined. In areas of normal lung, p63 decorated the reserve cells of large and small airways and occasional cells of the distal lobular unit. In fibrotic reactive processes, an interrupted but distinct pattern of nuclear staining was present in all cases, with staining of basal cells of the airways as well as bronchiolar- and squamous-metaplastic epithelium (43/43, 100%). p63 immunoreactivity was less uniform in areas of acute lung injury within these cases. One adenocarcinoma and two cases of atypical adenomatous hyperplasia showed strong immunoreactivity (>80%), while three adenocarcinomas highlighted only rare tumor nuclei (<5% of tumor cells). Morphologic areas where p63 immunostaining was not helpful included the junction of normal lung and lepidic growth of adenocarcinoma, and retrograde spread of adenocarcinoma into small airways. Our results highlight the differential expression of p63 across various bronchioloalveolar lesions. Moreover, p63 may be helpful in distinguishing reactive from neoplastic glandular proliferations in the lung.

Human neutrophil defensins and secretory leukocyte proteinase inhibitor in squamous metaplastic epithelium of bronchial airways.

The aim of this study was to analyze a possible contribution of human neutrophil defensins and secretory leukocyte proteinase inhibitor (SLPI) to the induction of airway epithelial changes such as squamous cell metaplasia. The presence of these molecules and the number of proliferating (Ki-67-positive) epithelial cells was analyzed by immunohistochemistry in bronchial epithelium from subjects with (n = 15) or without (n = 14) chronic obstructive pulmonary disease (COPD). Our data demonstrate higher numbers of defensin-positive (p = 0.0001), elastase-positive (p = 0.0001) and Ki-67-positive (p = 0.0001) cells in areas with squamous cell metaplasia as compared to areas with intact or damaged epithelium, while the reverse was observed for SLPI expression (p = 0.002). No differences were observed between subjects with or without COPD, nor between current smokers and those that had stopped smoking. These data are in line with a role of defensins in the hyperproliferative phenotype of squamous metaplastic lesions in the airways. This role does not seem to be restricted to patients with COPD.

Expression of CD44 protein in bilharzial and non-bilharzial bladder cancers.

To investigate the expression of CD44 protein in bilharzial and non-bilharzial bladder carcinomas, and to relate the results of immunohistochemistry to the established prognostic factors, as studies clearly show that altered adhesive function of tumour cells is important in the metastatic process and CD44 is assumed to be critical in the malignant progression of many human tumours. The study included 55 patients with bladder carcinoma confirmed by cystoscopy and biopsy. Of the 33 patients with transitional cell carcinoma (TCC), 19 were bilharzial and 14 non-bilharzial, and of 22 with squamous cell carcinoma (SCC), 12 were bilharzial and 10 non-bilharzial. CD44 expression was measured by immunohistochemical analysis of paraffin-embedded tissue obtained from these patients after appropriate treatment (transurethral resection, partial or radical cystectomy). There was significantly less CD44 expression in invasive TCC than in normal urothelium and pre-invasive TCC (P = 0.05). The expression of CD44 was inversely related to the tumour grade and depth of invasion (P = 0.05). However, there was no such relation for SCC; there was no significant difference between CD44 expression in metaplastic squamous epithelium, pre-invasive and invasive SCC. The presence or absence of bilharzial ova had no apparent effect on the expression of CD44, with no significant difference between CD44 expression in bilharzial and non-bilharzial bladder carcinomas. These data confirm that there is a reduction in CD44 expression with increasing tumour grade and stage of TCC, and may provide an additional aid in predicting the progression of this tumour. There was no such relationship with SCC, and no difference between CD44 expression in bilharzial and non-bilharzial bladder carcinomas.

Microscopic analysis of chromium accumulation in the bronchi and lung of chromate workers.

It is known that chromium is an inhaled carcinogen and an important risk factor in the development of lung carcinoma. The authors used a microscopic X-ray fluorescence analyzer with transmitted X-ray mapping imaging (Horiba, Kyoto, Japan) to measure the accumulation of chromium in 10 resected lung tissue specimens and 90 biopsy specimens from chromate workers. The maximum chromium accumulation (mean +/- standard deviation) in 10 resected lung tissue specimens was 197 +/- 238 counts per second (cps)/mili ampere (mA) (range, 4-649 cps/mA). Chromium accumulation was scattered in six tissue specimens and diffuse in one specimen. Chromium accumulation in the proximal bronchi was less than in the bronchioles or subpleural regions of the lung. Chromium accumulation was detectable in 63 (70%) of 90 biopsy specimens, and the mean accumulation was 6.5 +/- 9.2 cps/mA (range, 0-46.5 cps/mA). Chromium detected in bronchial tissue specimens was deposited in the bronchial stroma but not in the epithelium. The maximum chromium accumulations in dysplasic (n = 3), squamous metaplastic (n = 10), and normal bronchial epithelia (n = 9) in chromate workers and in normal bronchial epithelia (n = 3) in non-chromate workers were 20.2 +/- 5.4, 18.3 +/- 12.2, 13.2 +/- 13.4, and 3.0 +/- 1.8 cps/mA, respectively. The amount of chromium accumulation significantly increased according to the progression of malignant change of the bronchial epithelium (P = 0.003). Previous studies found that lung carcinoma with chromate exposure exhibited a variety of genetic abnormalities. Considering genetic aberrations and chromium accumulation in these premalignant lesions is useful for elucidating the process of carcinogenesis in chromium-induced lung carcinoma.

Differential regulation of nonsteroidal anti-inflammatory drug-activated gene in normal human tracheobronchial epithelial and lung carcinoma cells by retinoids.

In this study, we analyze the effect of several retinoids on the expression of nonsteroidal anti-inflammatory drug-activated gene (NAG-1) in normal human tracheobronchial epithelial (HTBE) cells and several lung carcinoma cell lines. The retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (AHPN) greatly enhances the expression of NAG-1 mRNA and protein in a time- and dose-dependent manner in human lung adenocarcinoma H460 cells and several other carcinoma cell lines. This induction was specific for AHPN because retinoic acid, a retinoic acid receptor-, and a retinoid X receptor pan-agonist were unable to induce NAG-1, suggesting that this induction is not mediated through activation of retinoid receptors. Although NAG-1 is a p53-responsive gene, AHPN-induced NAG-1 expression does not require p53. The induction of NAG-1 expression by AHPN is caused at least in part by an 8-fold increase in the stability of NAG-1 mRNA. In contrast to carcinoma cells, NAG-1 expression is effectively induced by retinoic acid and the RAR-selective pan-agonist in normal HTBE cells and accompanies the inhibition of squamous differentiation and the initiation of normal differentiation. In vivo, NAG-1 expression was observed in the normal tracheobronchial epithelium, whereas no expression was found in either squamous metaplastic tracheal epithelium or in sections of human lung tumors. Our results suggest that the induction of NAG-1 expression by retinoids in normal HTBE and lung carcinoma cells is regulated by distinct mechanisms and is associated with different biological processes. The linkage between AHPN treatment and NAG-1 expression revealed in this study provides a new mechanism for the antitumorigenic activity of AHPN.

P63 In pulmonary epithelium, pulmonary squamous neoplasms, and other pulmonary tumors

p63 is a p53-homologous nuclear protein that appears to play a crucial role in regulation of stem cell commitment in squamous and other epithelia. In this study, p63 expression was examined in benign lung and in neoplasms of pulmonary origin. Eighty sections from routinely fixed and processed archival bronchoscopic biopsy or lobectomy specimens were pretreated with citric acid (pH 6.0) for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained using a streptavidin-biotin kit and diaminobenzidine as chromagen, and were counterstained with hematoxylin. In normal lung, p63 intensely stained nuclei of bronchial reserve cells but did not stain ciliated cells, alveolar epithelial cells, or nonepithelial cells. The lower strata of squamous metaplastic bronchial epithelium stained positively. All squamous-cell carcinomas stained positively (n = 30). In some well-differentiated carcinomas, staining was found at the periphery of tumor nests but was negative in central zones showing squamous maturation. Poorly differentiated carcinomas showed very high proportions (80% to 100%) of p63-positive nuclei. All small-cell carcinomas were p63 negative (n = 9). Staining of bronchioloalveolar carcinomas (n = 7) and adenocarcinomas (n = 23) was variable: some tumors showed no detectable staining, others showed heterogeneously positive staining. Adenosquamous carcinomas (n = 5) displayed a unique basalar staining pattern. Carcinoid tumors were almost entirely negative (n = 5). We conclude that p63 is expressed in benign bronchial stem cells, in neoplastic cells with either squamous differentiation or squamous differentiating potential, and in a subpopulation of adenocarcinomas. p63 immunostaining may also aid in some histopathologic distinctions, such as in small biopsies where the differential diagnosis is poorly differentiated squamous carcinoma versus small-cell carcinoma. A stem cell biology–based classification system for squamous carcinomas is proposed. (HUM PATHOL 33:921-926. Copyright 2002, Elsevier Science (USA). All rights reserved.

Cytokeratin expression patterns in jaw cyst linings with metaplastic epithelium.

Cytokeratin (CK) expression patterns have been studied in numerous intact and diseased oral tissues. However, CK expression in metaplastic squamous cells has not been explored in depth and the origin of metaplastic epithelial linings of the jaw cysts has not been sufficiently investigated. We examined CK expression in 46 postoperative maxillary cysts (POMCs) which were lined with pseudostratified columnar cells only, columnar and squamous cells, and squamous cells only, in 13, 30 and 3 cases, respectively. The expression of CK8, CK13 and CK18 were observed in 39, 9 and all 43 of the columnar epithelial linings, respectively. Metaplastic squamous epithelia expressed more CK13, and less CK18 and CK8. Of the 33 metaplastic linings, 24 expressed CK8, 23 CK13 and 26 linings expressed CK18. The patterns of expression of CK13 and CK18 observed were CK18(+)-CK13(-) in 10 metaplastic linings, CK18(+)-CK13(+) in 16, and CK18(-)-CK13(+) in 7. The expression of CK13- and CK18-mRNA was generally correlated with level of protein expressed. CK18-mRNA expression was observed by in situ hybridization, not only in the 26 metaplastic linings which were positive for CK18 protein, but also in five of the seven metaplastic linings which did not express CK18 protein. In addition, RT-PCR revealed an expression of CK18-mRNA in all metaplastic squamous linings, although the expression level was weaker than that in the columnar epithelial linings. The CK13-mRNA was expressed inversely to the CK18-mRNA. These results indicate that CK18-mRNA is preserved through metaplasia, although the protein expression decreased. Metaplastic squamous cells differentiate with a decrease of CK18 and an increase of CK13 expression.

Ber‐EP4 immunoreactivity depends on the germ layer origin and maturity of the squamous epithelium

To map the expression of Ber-EP4 in well-differentiated squamous epithelia, metaplastic squamous epithelia and dysplastic squamous epithelia of different origins. Squamous epithelium of different origin was stained using a standard immunohistochemistry method applied to paraffin sections. We found that normal squamous epithelium of the oral cavity, oesophagus, uterine cervix, vagina, anal canal, and branchial cysts are Ber-Ep4-negative, as are the mature squamous metaplasia of bronchial mucosa, urinary bladder mucosa and uterine cervical mucosa. In contrast, immature squamous metaplasia of bronchial mucosa, or uterine cervical mucosa, and squamous dysplasia of oral mucosa of endodermal origin, or uterine cervical mucosa in most cases expressed Ber-EP4. Squamous epithelia of ectodermal origin never express Ber-EP4, whether normal, hyperplastic, dysplastic or neoplastic. In contrast, squamous epithelium of endodermal origin sometimes contains the target glycoproteins of Ber-EP4 when immature, metaplastic, dysplastic or neoplastic. The results indicate that the differences in expression of Ber-EP4 in squamous epithelium depend primarily on germ layer origin, and on the maturity of the epithelium.

Ki-67, cyclin E, and p16INK4 are complimentary surrogate biomarkers for human papilloma virus-related cervical neoplasia.

Prior studies of Ki-67, cyclin E, and p16 expression have suggested that these biomarkers may be preferentially expressed in cervical neoplasia. This study examined and compared the distribution of staining for these three antigens in 1) normal and reactive epithelial changes, 2) diagnostically challenging cases (atypical metaplasia and atypical atrophy), 3) squamous intraepithelial lesions (SIL), and 4) high-and low-risk human papilloma virus (HPV) type-specific SIL. One hundred four epithelial foci from 99 biopsies were studied, including low-grade squamous intraepithelial lesions (LSIL; 24), high-grade squamous intraepithelial lesions (HSIL; 36), mature or immature (metaplastic) squamous epithelium (29), and atrophic or metaplastic epithelium with atypia (15). Cases were scored positive for Ki-67 expression if expression extended above the basal one third of the epithelium, for cyclin E if moderate to strong staining was present, and for p16 if moderate to strong diffuse or focal staining was present. HPV status was scored by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of extracted DNA. Immunohistochemical findings were correlated with histologic and viral data. Overall, a histologic diagnosis of SIL correlated strongly with all of the biomarkers used (p <0.001). Positive scores for Ki-67, cyclin E, and p16 were seen in 68.4%, 96.7%, and 100% of LSILs and 94.7%, 91.6%, and 100% of HSILs, respectively. Positive predictive values of these three biomarkers for HPV were 82.4%, 89.5%, and 91.4%, respectively. The positive predictive value for HPV of either cyclin E or p16 was 88.7%. Strong diffuse staining for p16 was significantly associated with high-risk HPV-associated lesions. Normal or reactive epithelial changes scored positive for the three biomarkers in 7.7%, 8.0%, and 12%, respectively. Limitations in specificity included minimal or no suprabasal staining for Ki-67 in immature condylomas and occasional suprabasal staining of reactive epithelial changes (10%), diffuse weak nuclear cyclin E staining in some normal or metaplastic epithelia, and diffuse weak basal p16 staining and occasional stronger focal positivity in normal epithelia. Ki-67, cyclin E, and p16 are complementary surrogate biomarkers for HPV-related preinvasive squamous cervical disease. (Because cyclin E and p16 are most sensitive for LSIL and HSIL [including high-risk HPV], respectively, use of these biomarkers in combination for resolving diagnostic problems, with an appreciation of potential background staining, is recommended.)