Carcinoma Samples (carcinoma + sample)

Distribution by Scientific Domains


Selected Abstracts


Oral lichen planus has a high rate of TP53 mutations.

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2002
A study of oral mucosa in Iceland
Oral squamous cell carcinoma (OSCC) is a world-wide health problem. In addition to external exposure (smoking and alcohol), certain oral lesions may increase the risk of oral cancer (e.g. leukoplakia, erythroplakia, and oral lichen planus). TP53 has been implicated in OSCC, but there are limited studies of mutations in premalignant oral lesions. In this study, 55 samples from OSCC, 47 from hyperkeratotic (HK) oral mucosa, clinically diagnosed as white patches, 48 samples from oral lichen planus (OLP), and 12 biopsies from normal oral mucosa were studied immunohistochemically for expression of TP53 protein. From all the carcinoma samples and selected non-malignant samples showing moderate or strong TP53 protein expression, malignant cells or TP53-positive nuclei were microdissected and screened for mutations in exons 5,8 by constant denaturation gel electrophoresis. Moderate to strong TP53 protein staining was seen in 56% of OSCC, 32% of OLP but only in 13% of HK. All OLP samples showed a characteristic pattern of positive nuclei confined to the basal layer, whereas TP53 staining was seen in suprabasal nuclei in HK. Mutation rate was 11 out of 52 for OSCC, three out of 20 tested for HK and, remarkably, nine out 27 tested for OLP. There was no correlation between TP53 protein staining and TP53 mutations. No associations were found with anatomical sites or disease progression. The unexpectedly high mutation rate of OLP might explain the premalignant potential of this lesion. [source]


HMGA2 overexpression in non-small cell lung cancer

MOLECULAR CARCINOGENESIS, Issue 7 2007
Britta Meyer
Abstract Lung cancer is still the leading cause of death from cancer worldwide primarily because of the fact that most lung cancers are diagnosed at advanced stages. Overexpression of the high mobility group protein HMGA2 has been observed in a variety of malignant tumors and often correlates with poor prognosis. Herein, HMGA2 expression levels were analyzed in matching cancerous and non-cancerous lung samples of 17 patients with adenocarcinoma (AC) and 17 patients with squamous cell carcinoma (SCC) with real-time quantitative RT-PCR (qRT-PCR). Transcript levels were compared to results obtained by immunohistochemistry (IHC). HMGA2 expression was detectable by qRT-PCR in all samples tested and varied from 5422 to 16,991,545 copies per 250 ng total RNA in the carcinoma samples and from 289 to 525,947 copies in the non-cancerous tissue samples. In 33/34 non-small cell lung cancer (NSCLC) samples tested, an overexpression of HMGA2 was revealed with statistically highly significant differences between non-neoplastic and tumor samples for both AC (P,<,0.0001) as well as for SCC (P,<,0.0001). Expression varies strongly and is increased up to 911-fold for AC and up to 2504-fold for SCC, respectively, with statistically significant higher increase in SCC (P,<,0.05). The results presented herein indicate that HMGA2 overexpression is a common event in NSCLC and could serve as molecular marker for lung cancer. © 2007 Wiley-Liss, Inc. [source]


Integrative analysis of cancer pathway progression and coherence

PROTEOMICS - CLINICAL APPLICATIONS, Issue 4 2009
Ertugrul Dalkic
Abstract We analyzed the cancer pathways in the KEGG (Kyoto Encyclopedia of Genes and Genomes) database. The database provides a collective of signaling pathway members involved in cancer progression. However, the KEGG cancer pathways, unlike signaling pathways, have not been analyzed extensively with gene expression and mutation data. We transformed the colorectal cancer pathway into discrete X and Y scales and analyzed the relative expression levels of adenoma and carcinoma samples as well as the distribution of mutation targets. The X scale corresponds to the downstream location in a pathway, whereas the Y scale corresponds to the stage of the tumor. The gene expression values of the early stage pathway members are significantly higher than of the rest of the pathway members in colorectal adenoma tissues. The colorectal cancer pathway shows some degree of coherence in the carcinoma samples. The correlated gene pairs responsible for the coherence of the colorectal cancer pathway in the carcinoma samples are supported, in part, by the literature and may suggest novel regulatory associations. Finally, there are more mutation targets in the nucleus as well as the late tumor stages of the KEGG colorectal cancer pathway. [source]


Immunohistochemical expression of tumor antigens MAGE-A1, MAGE-A3/4, and NY-ESO-1 in cancerous and benign prostatic tissue

THE PROSTATE, Issue 1 2006
Tvrtko Hudolin
Abstract OBJECTIVE To investigate immunohistochemical expression of MAGE-A and NY-ESO-1/LAGE-1, cancer testis antigens in prostate tissues showing evidence of malignant transformation or benign hyperplasia. METHODS 112 prostate samples from patients undergoing surgery at the Urology Clinic at the Zagreb Clinical Hospital Center from 1995 to 2003 were investigated in this study. Of these, 92 carcinoma samples were obtained by radical prostatectomy, and 20 benign prostatic hyperplasia samples by transvesical prostatectomy. Three monoclonal antibodies were used for immunohistochemical staining: 77B for MAGE-A1, 57B for multi-MAGE-A and D8.38 for NY-ESO-1 expression. RESULTS Expression of MAGE-A1 was observed in 10.8% of carcinoma samples, whereas multi-MAGE-A and NY-ESO-1/LAGE-1 stained 85.9% and 84.8% of samples. Immunohistochemical staining was only detectable in the cytoplasm. A significant heterogeneity could be observed within a same tissue sample where areas with strong positivities coexisted with cancer testis antigens negative areas. Interestingly, a majority of 57B positive cases were also found to be D8.38 positive (correlation coefficient r,=,0.727 (P,<,0.01)). Cancer testis antigens expression was neither significantly correlated with PSA values nor with Gleason score. In benign prostatic hyperplasia tissues MAGE-A1 expression was detected in 5%, while 57B and D8.38 staining was observed in 15% samples, and in all cases percentages of positive cells were always <10%. CONCLUSION Our data underline the peculiar relevance of cancer testis antigens expression in prostate cancers, with potential implications regarding both diagnosis and therapy. © 2005 Wiley-Liss, Inc. [source]


Wilms tumor gene protein 1 is associated with ovarian cancer metastasis and modulates cell invasion

CANCER, Issue 7 2008
Maria V. Barbolina PhD
Abstract BACKGROUND Although metastatic disease is the primary cause of death from epithelial ovarian carcinoma, to the authors' knowledge the cellular mechanisms that regulate intraperitoneal metastasis are largely unknown. Metastasizing ovarian carcinoma cells encounter a collagen-rich microenvironment because the submesothelial matrix is comprised mainly of interstitial collagens Types I and III. METHODS Immunohistochemistry using primary and metastatic ovarian carcinoma samples was employed to detect expression of Wilms tumor gene protein 1 (WT1). Three-dimensional (3D) collagen culture, real-time reverse transcriptase-polymerase chain reaction, and immunofluorescent staining were used to evaluate changes in WT1 RNA and protein expression in response to 3D collagen culture. Boyden chamber invasion assay, scratch-wound motility assay, and Western blot analysis were used to establish the function of WT1 in ovarian carcinoma cells. RESULTS To model intraperitoneal invasion in vitro, ovarian cancer cells were cultured in a 3D collagen microenvironment. 3D collagen culture resulted in robust induction of WT1 at the mRNA and protein levels. WT1 expression was prevalent in primary ovarian tumors and was retained in paired peritoneal metastases. Functional studies supported a role for WT1 in intraperitoneal invasion, because siRNA knockdown of WT1 expression reduced the ability of ovarian cancer cells to invade 3D collagen gels. CONCLUSIONS The data from the current study identify a novel regulatory mechanism for the control of WT1 expression and provide evidence for a functional role of WT1 protein in the control of cellular invasive activity. Cancer 2008. ©2008 American Cancer Society. [source]


The expression of Bcl-2 family proteins differs between nonsmall cell lung carcinoma subtypes

CANCER, Issue 7 2005
Helen K. Berrieman Ph.D.
Abstract BACKGROUND Proteins of the Bcl-2 family play a key role in the control of apoptosis and carry out both proapoptotic and antiapoptotic functions. However, with the exception of Bcl-2 itself, little is known about the expression of these potentially critical proteins in nonsmall cell lung carcinoma. METHODS Immunohistochemistry was used to study the expression of Bcl-2 and 6 other Bcl-2 family proteins in a pilot series of 41 archival nonsmall cell lung carcinoma specimens (19 adenocarcinomas and 22 squamous cell carcinomas). RESULTS Overexpression of the apoptosis inhibitors Bcl-2 and Bcl-XL was observed in 10 of 41 samples (24%) and in 11 of 41 samples (27%), respectively. Loss of expression of proapoptotic proteins was observed as follows: Bak, 24 of 41 samples (59%); Bad, 21 of 41 samples (51%); Bid, 20 of 41 samples (49%); Bax, 14 of 41 samples (34%); and Bim/Bod, 2 of 41 samples (5%). Statistically significant differences in expression between adenocarcinoma samples and squamous cell carcinoma samples were observed for Bcl-XL (overexpression in 11 of 19 adenocarcinomas [58%] vs. 0 of 22 squamous cell carcinomas [0%]; P < 0.001) and for Bad (loss of expression in 5 of 19 adenocarcinomas [26%] vs. 16 of 22 squamous cell carcinomas [73%]; P = 0.004). CONCLUSIONS Although this was only a pilot study, the results revealed significant differences in the expression of apoptosis-related proteins both between individual samples of nonsmall cell lung carcinoma and between the two main histologic subtypes. Such differences may play a role in the development of lung tumors; and, if it is found that these differences are of clinical importance, then it may be required to regard nonsmall cell lung carcinoma subtypes as separate entities rather than as one disease. Cancer 2005. © 2005 American Cancer Society. [source]


Immunohistochemical analysis of CYP2A13 in various types of human lung cancers

CANCER SCIENCE, Issue 4 2010
Tatsuki Fukami
Human CYP2A13, which is expressed in the respiratory tract, is the most efficient enzyme for the metabolic activation of tobacco-specific nitrosamines such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The relevance of CYP2A13 in carcinogenicity and toxicity in the respiratory tract has been suggested, but the expression of CYP2A13 protein in lung cancer tissues remains to be determined. We first prepared a mouse monoclonal antibody against human CYP2A13. The antibody showed no cross reactivity with the other CYP isoforms including CYP2A6. Using the specific antibody, we performed immunohistochemical analysis for human lung carcinomas. In adenocarcinomas (n = 15), all specimens were positive for the staining and five samples showed strong staining. In squamous cell carcinomas (n = 15) and large cell carcinomas (n = 15), each 14 samples were positive for the staining and two and three samples showed strong staining, respectively. In small cell carcinoma samples (n = 15), eight samples were negative for the staining and five samples showed weak or moderate staining. In conclusion, we first found that the expression of CYP2A13 was markedly increased in non-small cell lung carcinomas. The high expression might be associated with the tumor development and progression in non-small cell lung carcinomas. (Cancer Sci 2010; 101: 1024,1028) [source]


Differential expression of p53, p63 and p73 proteins in human buccal squamous-cell carcinomas

CLINICAL OTOLARYNGOLOGY, Issue 5 2003
Y.K. Chen
Abnormalities in the p53 gene are regarded as the most consistent of the genetic abnormalities in oral squamous-cell carcinoma. Two new members of the p53 gene family, p73 and p63, have recently been identified, with the three sharing considerable sequence homology at the acidic N-terminal transactivation, central DNA-binding and C-terminal oligomerization domains, indicating possible functional and biological interactions. The differential expression of p73, p63 and p53 genes in human oral squamous-cell carcinoma does not yet appear to be completely understood, however. In this study, therefore, immunohistochemical analysis of protein expression was performed for 40 samples of well-differentiated human buccal squamous-cell carcinomas, with 10 specimens of normal buccal mucosa employed as controls. Differential expressions of p63, p73 and p53 proteins in the carcinoma samples were: p63+/p73+/p53 + (n = 28; 70%); p63+/p73+/p53, (n = 4; 10%); p63+/p73,/p53, (n = 8; 20%), respectively; and p63+/p73+/p53, for normal mucosa (n = 10; 100%). A significant correlation between p53, p63 and p73 immunoexpression was demonstrated for the buccal squamous-cell carcinoma samples (P < 0.0001; Fisher's exact test). Significance was not achieved for the correlation between p73 and p53 immunoexpression and clinicopathological parameters for buccal carcinomas (P > 0.05; Fisher's exact test). Our results indicate that both p73 and p63 may be involved in the development of human buccal squamous-cell carcinoma, perhaps in concert with p53. [source]