EXPRESSION OF THE LAMININ γ2 CHAIN IN PANCREATIC ADENOCARCINOMA

Forty-two pancreatic adenocarcinomas were investigated immunohistochemically and by in situ hybridization for the expression of the laminin γ 2 chain. In 41 cases, intracytoplasmic immunoreactivity for the γ2 chain was seen. Positive tumour cells were located especially at the epithelial–stromal interface of the tumour cell islands. In 22 cases, diffuse laminin γ2 chain immunoreactivity could also be seen in stroma and in seven cases, occasional positivity was detected in the neoplastic basement membranes. Signals for laminin γ2 chain mRNA in tumour cells displayed a distribution similar to that observed on immunohistochemistry. There were significantly more cases with less than 20 per cent of laminin γ2 chain-positive tumour cells in tumours extending to peripancreatic tissues and/or tumours with regional or distant metastases ( P =0·029). A corresponding statistical significance could also be noted in the mRNA level ( P =0·025). The results show that pancreatic adenocarcinomas display a high activity of laminin γ 2 chain synthesis. Tumours with a strong laminin γ2 chain synthesis show a lower invasive and metastatic potential than tumours with a weak or moderate laminin γ2 chain expression.     

Laminin alpha2 chain (merosin M chain) distribution and VEGF, FGF(2), and TGFbeta1 gene expression in angiogenesis of supraglottic, lung, and breast carcinomas

The prognostic significance of vessel quantification in human solid tumours is still debated, due to the presence of multiple factors modulating neoangiogenesis and the invasiveness of neoplastic cells. This study examined ten supraglottic squamous carcinomas, ten non-small cell lung carcinomas (three squamous, five bronchioloalveolar, two adenocarcinomas), and nine classic (NOS) invasive ductal breast carcinomas. The properties studied in these tumours were vascularity; the immunohistochemical distribution of adhesion molecules such as alpha2beta1, alpha3beta1, alpha4beta1, alpha5beta1, alpha6beta4, and ICAM-1 in endothelial cells; extracellular matrix proteins (ECMPs) and laminin alpha2 chain (merosin M chain) in basal membranes of vessels; and gene expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF2), and transforming growth factor beta1 (TGFbeta1), by in situ hybridization. Independently of tumour type and vascularity, laminin alpha2 chain expression was observed in the basal membranes of a limited proportion of vessels. In vitro experiments demonstrated laminin alpha2 chain expression mainly in early endothelial cell cultures, suggesting that laminin alpha2 chain expression in vivo can be considered a marker of early angiogenesis. Stromal and parenchymal vascularity was associated with laminin alpha2 chain expression in supraglottic carcinomas, whereas in the other tumours, laminin alpha2 chain-positive vessels were observed only in the stroma. In supraglottic carcinomas, VEGF-positive cells were mainly represented by neoplastic cells, whereas in the other tumours, the great majority of VEGF-positive cells were macrophages and fibroblasts. FGF2- and TGFbeta1-positive cells were macrophages and fibroblasts in all tumours. These observations suggest that in addition to the quantification and distribution of vessels, evaluation of their maturation may contribute to a better understanding of the role of angiogenesis in the growth and spread potential of solid tumours. In this regard, in supraglottic carcinomas, parenchymal angiogenesis seems to be regulated mainly by neoplastic cells, which may help to explain their high metastatic potential; in solid tumours of different histogenesis, different cells might be responsible for modulating tumour angiogenesis.     

Lowp53 protein expression in salivary gland tumours compared with lung carcinomas

Summary Fifty-one salivary gland tumours (23 pleomorphic adenomas, 5 Warthin's tumours, 12 mucoepidermoid carcinomas, 7 adenoid cystic carcinomas, 3 undifferentiated carcinomas and 1 acinic cell tumour) and 27 lung carcinomas (18 squamous cell carcinomas, 6 adenocarcinomas and 3 small cell carcinomas) were analysed immunohistochemically for the expression ofp53 nuclear phosphoprotein. Eight out of 51 (16%) salivary gland tumours werep53 positive. Three of these were benign and 5 malignant. All 3 benign salivary gland tumours were pleomorphic adenomas and expressed only occasional nuclear positivity with less than 1% of tumour cells positive. Of the 5p53-positive malignant tumours, 3 were mucoepidermoid carcinomas and 2 undifferentiated carcinomas. The malignant salivary gland tumours expressed more than 1% of positive nuclei in every case. Seventeen lung carcinomas werep53 positive (63%). Thirteen of these were squamous cell carcinomas, 3 were adenocarcinomas and 1 small cell lung carcinoma. The results show that mutations of thep53 gene may be infrequent in salivary gland tumours when compared with lung carcinomas. The relatively indolent course of some histological types of malignant salivary gland tumours could be associated with the preservation of the non-mutatedp53 gene in most of these tumours. The presence ofp53 positivity in some pleomorphic adenomas might, on one hand, suggest thatp53 gene alterations are also present in these tumours; on the other hand, the accumulation of thep53 protein in these tumours might also be due to some unknown mechanism, not necessarily related top53 gene mutation.     

Differential expression of neural-cadherin in pulmonary epithelial tumours

Aims:  Neural (N)-cadherin belongs to a group of transmembrane molecules with a crucial role in tissue morphogenesis and maintenance of an epithelioid phenotype and increased N-cadherin expression is implicated in tumour progression and dedifferentiation. The aim was to determine whether evaluation of N-cadherin in pulmonary tumours might assist in identifying lesions with more aggressive potential.
Methods and results:  One hundred and fifty-five pulmonary lesions were analysed for N-cadherin expression using immunohistochemistry, including neuroendocrine hyperplasia ( n  = 3), typical carcinoid ( n  = 59), atypical carcinoid ( n  = 12), small cell lung carcinoma ( n  = 11), large cell neuroendocrine carcinoma ( n  = 12), adenocarcinoma ( n  = 35) and squamous cell carcinoma ( n  = 23). Lymph node status was correlated with immunohistochemical expression. N-cadherin expression was demonstrated in all cases of neuroendocrine hyperplasia, 96% of typical carcinoids, 83% of atypical carcinoids, 63% of the small cell lung carcinomas and 32% of large cell neuroendocrine carcinomas. Over 90% of the adenocarcinomas and 100% of the squamous cell carcinomas were negative. Increased N-cadherin expression in typical carcinoids was associated with negative lymph node status ( P  < 0.001).
Discussion:  N-cadherin is differentially expressed in pulmonary tumours and is predominantly observed in neuroendocrine lung lesions with high expression in typical and atypical pulmonary carcinoids. The level of expression of N-cadherin between types of lung tumours does not appear to indicate malignant potential or aggressive behaviour.     

Expression of aquaporin3 in human neoplastic tissues

Niu D, Kondo T, Nakazawa T, Yamane T, Mochizuki K, Kawasaki T, Matsuzaki T, Takata K & Katoh R
(2012) Histopathology  61, 543–551 Expression of aquaporin3 in human neoplastic tissues Aims: Aquaporin3 (AQP3) is distributed widely in mammalian tissues and plays an important role in fluid homeostasis. The aim of this study was to investigate the pattern of expression of AQP3 in a variety of human neoplastic tissues and to explore its diagnostic implications. Methods and results: We studied 798 neoplastic tissues using immunohistochemistry with anti‐AQP3 antibody. We demonstrated a high positive frequency of AQP3 immunoreactivity in pituitary adenomas, salivary gland tumours, thymic tumours, adenocarcinoma of the lung and prostate, squamous cell carcinomas of the skin, oesophagus and uterine cervix, apocrine carcinoma of the breast, germinal cell tumours of the ovary and testis and urothelial carcinoma of the bladder. None of the sarcomas or central nervous system tumours showed AQP3 immunoreactivity. Most tumours with a high frequency of AQP3 positivity had corresponding or surrounding normal cells that also expressed AQP3. AQP3 was not a specific marker for benign or malignant epithelial neoplasms. Conclusion: AQP3 protein is expressed in a variety of epithelial tumours limiting its use as a diagnostic marker. Furthermore, AQP3 expression in tumour cells reflected the expression status of AQP3 in the corresponding normal cells. Our data suggest that water metabolism through AQP3 is maintained during neoplastic transformation in most human tissues.     

Gain of 1q25-32, 12q23-24.3, and 17q12-22 facilitates tumorigenesis and progression of human squamous cell lung cancer

To explore the genetic changes involved in the stepwise development of lung cancer, we have determined the genetic events associated with the histological progression from normal bronchial epithelium to squamous cell carcinoma. Comparative genomic hybridization was used to identify chromosomal imbalances in 54 microdissected samples, including squamous metaplasia, dysplasia, carcinoma in situ, and invasive tumour derived from 23 patients with squamous cell carcinoma of the lung. Histopathological progression was accompanied by an increased number of chromosomal abnormalities. Gains of 1q25-32, 12q23-24.3, and 17q12-22, in particular, were detected at high frequencies in both carcinoma in situ and invasive tumours and were found more often in the cases with lymph node metastases than in those without. Our previous expression profiling of squamous cell carcinomas had identified overexpression of laminin5 gamma2, a gene located at 1q25-31. Therefore, this was investigated at the protein level by immunohistochemical analysis in 336 samples of squamous cell carcinoma of the lung. Consistent with the genomic data for this region, the expression level of laminin5 gamma2 was higher in the primary tumours with lymph node metastases than in tumours without metastases (p = 0.012). These data suggest that gains of genes from 1q25-32, 12q23-24.3, and 17q12-22 facilitate tumorigenesis and progression of squamous cell carcinoma of the lung, and may serve as potential predictors for this disease.     

Expression of extracellular matrix proteins in cervical squamous cell carcinoma--a clinicopathological study

AIM: To evaluate the intracellular and peritumoral expression of matrix proteins in squamous cell carcinoma of the uterine cervix using immunohistochemistry. METHODS: 71 squamous cell carcinomas and 10 controls were stained for laminin, fibronectin, and collagen IV. Cytoplasmic staining in tumour cells and peritumoral deposition of matrix proteins were evaluated. The association between staining results and patient age, tumour stage, histological grade, and survival was studied. RESULTS: Positive cytoplasmic staining for laminin, fibronectin, and collagen IV was observed in 17 (23.9%), 27 (38%), and 10 (14.1%) cases, respectively. Staining for laminin was most pronounced in the invasive front of tumour islands, while for fibronectin and collagen IV it appeared to be diffuse. Peritumoral staining for laminin and collagen IV was detected in 12 cases (16.9%). Early stage (Ia1-Ia2) tumours were uniformly negative for all three proteins. Cytoplasmic staining for laminin correlated with positive staining for fibronectin and collagen IV, and with the presence of a peritumoral deposition of collagen IV and laminin. There was no correlation with any of the three markers between staining results and patient age, stage, grade, or survival. CONCLUSIONS: Expression of extracellular matrix proteins in some cervical squamous cell carcinomas might reflect the enhanced ability of these tumours to modify the peritumoral stroma. This ability seems to be absent in early stage tumours. The correlation between intracytoplasmic and peritumoral expression of matrix proteins supports the evidence of their synthesis by tumour cells. However, this property did not correlate with disease outcome in this study.     

Langerhans cells in human lung tumours: an immunohistological study

In an immunocytochemical study of 41 human lung tumours we have shown that Langerhans cells can be reliably identified using the anti-CD1 monoclonal antibody NA1/34. Langerhans cells are present in all the main varieties of human lung tumour although they are infrequent in both small cell carcinoma and carcinoid tumour. There is considerable variation in numbers of Langerhans cells in both adenocarcinomas and squamous cell carcinomas. In this study tumours were divided into those with high numbers of Langerhans cells (greater than 2 per high power field) and those with low numbers (less than 2 per high power field). Analysing these results against patient survival showed a markedly worse survival in those tumours with a high number of Langerhans cells for all the tumours as a single group and for squamous cell carcinoma as a single entity.     

Immunohistochemical examination of lung cancers using monoclonal antibodies reacting with sialosylated Lewisx and sialosylated Lewisa

Summary In order to explore the relationship between the expression of cancer-associated glycolipids such as sialylated Le^x (SLEX) and sialylated Le^a (SLEA) and the histological subtypes of lung cancers, 30 cases of small cell carcinoma (SCC) and 47 cases of non-small cell carcinoma (non-SCC) were examined immunohistochemically using monoclonal antibodies reacting with SLEX and SLEA. The forty-seven cases of non-SCC included 20 cases of adenocarcinoma, 20 of squamous cell carcinoma and 7 of large cell carcinoma. Tumour cells of most non-SCCs expressed SLEX and SLEA. In adenocarcinomas, the number of tumour cells having SLEX and SLEA was more than that of squamous cell carcinomas, large cell carcinomas and SCC. In SCC, 14 of the 30 cases were found to be positive for both antigens. Although the cancer cells of 11 cases of 17 intermediate cell type SCC had both antigens, the cells of only 3 of 13 oat cell tumours expressed SLEX and SLEA. The present study shows that SLEX and SLEA are useful markers for lung adenocarcinomas, that most cases of intermediate cell type of SCCs have characteristics similar to non-SCC but that many oat cell tumours lack them.     

Protein 1 and Clara cell 10-kDa protein distribution in normal and neoplastic tissues with emphasis on the respiratory system

Thirty-six different normal tissues and 13 different malignant epithelial tumours, were examined immunohistochemically for the presence of protein 1 (P1) and Clara cell 10-kDa protein (CC10). Adenocarcinomas of the lung were also examined for the expression of pulmonary surfactant apoprotein using a monoclonal antibody (PE-10). The staining results of P1 and CC10 were almost identical both in normal tissues and in malignant tumours. In normal lung, Clara cells were strongly positive for both P1 and CC10. In addition, some goblet cells and non-ciliated non-mucus cells in the upper airways were moderately positive for both proteins. In the malignant tumours, some lung cancers were positive for P1 and CC10, both of which were positive in the same tumour cells on sequential sections. In 117 lung cancers, P1 and CC10 were positive in 10.2% of adenocarcinomas, 20.5% of squamous cell carcinomas, and 12.5% of large cell carcinomas. PE-10 stained positively in 65.3% of adenocarcinomas, a frequency significantly higher than that of P1 and CC10 (P<0.01). These results suggest that P1 and CC10 are nearly identical proteins, that both are useful markers of Clara cells, and that many pulmonary adenocarcinomas express surfactant apoprotein rather than Clara cell proteins.     

Human papillomavirus infection and invasive cervical neoplasia: a study of prevalence and morphology

The prevalence of human papillomavirus (HPV) DNA sequences in 45 cervical cancer biopsies was examined with the hot-start polymerase chain reaction (PCR), employing HPV consensus primers from the L1 region. The cases comprised 38 squamous cell carcinomas, three adenosquamous carcinomas, and four adenocarcinomas. PCR products were typed with single-strand conformation polymorphism (SSCP) and the HPV types detected were correlated with tumour type. Forty-three biopsies were HPV-positive, HPV16 being the most prevalent type. HPV18/33/45/58 were also detected, but no low-risk or multiple types. Keratinizing squamous cell carcinoma was invariably associated with HPV16 and adenosquamous carcinoma and adenocarcinoma with HPVs 18/45. Non-keratinizing squamous cell carcinomas harboured all five detected types. Our data corroborate the view that malignant cervical tumours are almost invariably associated with high-risk HPV and that certain malignant cervical tumour phenotypes correlate with specific HPV types. © 1997 John Wiley & Sons, Ltd.     

Laminin and type VII collagen distribution in different types of human lung carcinoma: correlation with expression of keratins 14, 16, 17 and 18

The expression patterns of basement membrane components and keratin intermediate filament proteins were studied in normal human bronchial epithelium and 56 lung carcinomas using monoclonal antibodies to laminin, type VII collagen and the individual keratins 14, 16, 17 and 18. In normal lung, laminin and type VII collagen were present between the epithelium and the lamina propria of bronchi and bronchioles. Keratin 14 was expressed in the basal cells, keratin 17 in the basal and some suprabasal cells and keratin 18 in the columnar cells of the bronchi and bronchioles. Keratin 16 was not present in normal bronchial epithelium. Laminin was found in all subtypes of lung carcinoma, but type VII collagen was present only in squamous cell carcinomas, where it showed a reduction in expression with decreasing differentiation. Type VII collagen was not identified in adenocarcinomas, small cell carcinomas or carcinoids. Antibodies to basal cell keratins 14 and 17 also displayed positivity only in squamous cell carcinomas, although no correlation with the degree of differentiation could be observed. Keratin 16 appeared to be a marker of the squamous phenotype, rather than of hyperproliferation. The keratin 18 marker for columnar epithelial cells showed a reaction pattern opposite to that of the basal cell keratins, being extensively present in adenocarcinomas, small cell carcinomas and carcinoids, with less expression in squamous cell carcinomas. This study shows a correlation between the presence of type VII collagen and the basal cell keratins 14 and 17, and a negative correlation between these components and keratin 18. These findings are likely to be useful in identifying lung cancer subtypes.     

Expression of c-erbB-2 oncoprotein in salivary gland tumours: an immunohistochemical study.

Sections of formalin-fixed, paraffin-embedded primary salivary gland tumours were stained with a monoclonal antibody to the c-erbB-2 oncoprotein to determine the incidence and significance of expression of this protein. The series of 131 tumours comprised 33 cases of pleomorphic adenoma, 2 of malignant mixed tumour, 1 oxyphil adenoma, 31 Warthin's tumours, 4 basal cell adenomas, 6 mucoepidermoid carcinomas, 14 acinic cell carcinomas, 19 adenoid cystic carcinomas, 3 squamous carcinomas, and 18 poorly differentiated adenocarcinomas. Positive staining, as defined in previous studies, was present in five tumours (three cases of poorly differentiated adenocarcinoma, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma). A review of the medical records of all patients did not disclose any clear difference between the clinical behaviour of positive and negative cases over a period of follow-up that ranged from 18 to 120 months. The findings of this study indicate that the protein product of the c-erbB-2 proto-oncogene is infrequently expressed in salivary gland tumours, and when it is localized on the tumour cell surface membrane, there is no clear evidence that this determines the biological behaviour of the tumour.     

Laminin 5 beta3 and gamma2 chains are frequently coexpressed in cancer cells

Laminin 5 plays an important role in cell migration during tumor invasion and tissue remodeling. However, previous studies have not clarified whether laminin 5 beta3 chain is coexpressed with laminin 5 gamma 2 chain in cancer cells. The present immunohistochemical study investigated the distribution of the laminin 5 beta3 and gamma2 chains in 20 cases of squamous cell carcinoma of the tongue and 17 cases of colorectal carcinoma. Laminin 5 beta3 and gamma2 chains were expressed in the cytoplasm of tumor cells. Tumor cells at the cancer-stromal interface and at the invasive front frequently showed immunopositivity for laminin 5 beta3 and gamma2 chains in both squamous cell carcinoma of the tongue and colorectal carcinoma. Furthermore, strong expressions of these two proteins were observed in cancer cells invading in a scattered manner. Laminin 5 beta3 expression correlated significantly with laminin 5 gamma2 expression in 20 cases of squamous cell carcinoma of the tongue (P = 0.0002) and 17 cases of colorectal carcinoma (P < 0.0001). These results suggest that in squamous cell carcinoma of the tongue and colorectal carcinoma, laminin 5 gamma2 chain and beta3 chain are both important in the invasiveness of cancer cells.     

Detection of the Epstein-Barr virus in primary adenocarcinoma of the lung with Signet-ring cells

The Epstein-Barr virus (EBV) is directly implicated in the pathogenesis of a variety of undifferentiated carcinomas and has also been identified in conventional adenocarcinomas of the stomach. To date, the association of EBV with non-small cell lung carcinoma is restricted to Asian patients. To evaluate the presence of EBV in lung cancers from Europeans, we investigated primary lung adenocarcinomas with a similar morphological tumour pattern to those of the stomach, specifically rare tumours with components of signet-ring cells. Three tumours of signet-ring cell type were examined by means of polymerase chain reaction (PCR). To localise the virus to the neoplastic cells, in situ hybridisation (ISH) was performed using an antisense Epstein-Barr virus encoded RNA probe. Immunohistochemistry was performed to evaluate the expression of latent membrane protein-1 (LMP-1) and EBV nuclear antigen 2 (EBNA-2). PCR investigation confirmed the presence of EBV in one case. Positive signals confined to tumour cells were present on ISH. None of the tumours showed expression of LMP-1 and EBNA-2. To our knowledge, this is the first report on the presence of EBV in primary adenocarcinoma of the lung in a Caucasian patient. The present study indicates that EBV may infect some lung cancers with a specific tumour pattern.     

Detection of endothelin immunoreactivity and mRNA in pulmonary tumours

Paraffin sections of 66 surgically resected lung tumours were immunostained with antisera to human endothelin-1 and to the C-terminal peptide of big endothelin. With both antisera, strong immunoreactivity was demonstrated in 11 of 15 squamous cell carcinomas and 11 of 16 adenocarcinomas. Focal immunoreactivity was seen in small cell carcinoma (2/12), large cell carcinoma (2/5), and carcinoid tumours (2/11). Four lymphomas and three sarcomas did not show endothelin immunoreactivity. Cryostat sections of 22 of the 66 tumours were hybridized with radiolabelled complementary RNA probes prepared from the 3' non-coding region of endothelin-1 cDNA, and the chromosomal genes encoding endothelin-2 and -3. In situ hybridization demonstrated the presence of endothelin mRNAs in 4 of 7 squamous cell carcinomas and in 5 of 8 adenocarcinomas, in a pattern similar to that shown by immunocytochemistry. No hybridization signals were obtained from the other types of tumours. In lung tissue adjacent to the tumours, endothelin-like immunoreactivity and mRNA were detected in pulmonary endocrine cells and, in some cases, other epithelial cells, and in alveolar capillary endothelial cells. This study demonstrates the expression of endothelin in a number of pulmonary tumours and suggests a possible role for this peptide in the growth and/or differentiation of these tumours.