Biomedical subjects

Graeme I Murray

Publications and source records attributed to Graeme I Murray.

At least 19 recordsLinked to original sources

PubMed2006

Raf kinase inhibitor protein expression in a survival analysis of colorectal cancer patients.

PURPOSE: Raf kinase inhibitor protein (RKIP) inhibits the Raf and nuclear factor kappa B signaling pathways, and suppresses metastasis in animal models. We examined whether RKIP expression in primary colorectal cancers (CRCs) correlates with the risk of metastasis and overall survival. PATIENTS AND METHODS: RKIP expression was examined immunohistochemically in three separate cohorts: a tissue microarray containing 276 samples from human tumors and normal tissues, and retrospective studies of 268 CRC patients and 65 early-stage CRCs. Overall and metastasis-free survival rates were measured. RESULTS: RKIP was expressed in normal epithelia but was reduced in metastatic tumors. RKIP expression in primary CRC was an independent prognostic marker for survival using multivariate Cox regression analysis (hazard ratio, 2.808; 95% CI, 1.58 to 4.96; P = .0002), independent of Dukes' stage. Patients with Dukes' C RKIP-positive tumors had similar 5-year survival rates as early-stage patients if tumors had equivalent RKIP expression levels. An independent study of early-stage CRCs confirmed that reduced RKIP expression predicted metastatic recurrence and reduced disease-free survival (hazard ratio, 4.5; 95% CI, 1.7 to 12.3; P = .003). RKIP expression was independent of sex, age, mitotic index, lymphatic and vascular invasion, depth of invasion, and tumor site, but correlated positively with apoptotic index (P = .024). Weak or loss of RKIP expression was the most significant and independent prognostic marker using a multivariate regression equation (hazard ratio, 4.5; 95% CI, 1.7 to 12.3; P = .003). CONCLUSION: RKIP expression in primary CRCs correlates with overall and disease-free survival, and can be useful for identifying early-stage CRC patients at risk of relapse.

Adult↗

PubMed2006

Tumor transcriptome reveals the predictive and prognostic impact of lysosomal protease inhibitors in non-small-cell lung cancer.

PURPOSE: Insight into clinical response to platinum-based chemotherapy (PBC) in non-small-cell lung cancer (NSCLC). METHODS: Matched tumor and nontumor lung tissues from PBC-treated NSCLC patients (four nonresponders and four responders) and tumor tissue from an independent test set (four nonresponders and four responders), were profiled using microarrays. Lysosomal protease inhibitors SerpinB3 and cystatin C were highly correlated with clinical response and were further evaluated by immunohistochemistry in PBC-treated patients (36 prechemotherapy and 13 postchemotherapy). Investigation of the pathogenic and prognostic significance of SerpinB3 was performed in 251 primary tumors, with 64 regional lymph node pairs, from chemotherapy-naïve NSCLC patients using immunohistochemistry. RESULTS: Bioinformatic analyses of gene expression in the training set identified a gene set (n = 17) that separated all patients in the training and test sets (n = 16) according to response in hierarchical clustering. Transcriptome profiling revealed that SerpinB3 mRNA was highly correlated with degree of response (r = -0.978; P < .0001) and was a clear outlier (nonresponders:responders > 50-fold). SerpinB3 protein expression was correlated with clinical response in PBC-treated NSCLC patients (P = .045). Expression of SerpinB3 and cystatin C, relative to the target, protease cathepsin B, was independently predictive of response (odds ratio, 17.8; 95% CI, 2.0 to 162.4; P = .01), with an accuracy of 72%. High SerpinB3 expression levels, invariably associated with chemoresistance, had contrasting prognostic impact in untreated squamous cell carcinomas (hazard ratio [HR], 0.43; 95% CI, 0.18 to 0.93) or adenocarcinomas (HR, 2.09; 95% CI, 1.03 to 4.72). CONCLUSION: This provides the first comprehensive molecular characterization of clinical responsiveness to PBC in NSCLC and reveals the predictive and prognostic impact of two lysosomal protease inhibitors, potentially representing novel targets for NSCLC therapeutics.

Aged↗

PubMed2006

Profiling markers of prognosis in colorectal cancer.

PURPOSE: Colorectal cancer is one of the most common forms of cancer in developed nations and the incidence of this disease is increasing. There is a need to further stratify prognostically distinct groups of colorectal cancer, and the purpose of this study was to identify prognostically significant immunohistochemical marker profiles in colorectal cancer. EXPERIMENTAL DESIGN: In this study, a range (n = 23) of markers [pRb, p16, p21, p27, p53, proliferating cell nuclear antigen, cyclin D1, bcl-2, epidermal growth factor receptor, C-erb-B2, topoisomerase-I, liver fatty acid-binding protein, matrix metalloproteinases (MMP) 1-3, 7, 9, and 13, MT1-MMP, MT2-MMP, and tissue inhibitors of MMP 1-3] of putative prognostic significance have been investigated by immunohistochemistry on formalin-fixed, wax-embedded sections in a series (n = 90) of stage III (Dukes C) colorectal cancers. An immunohistochemical score based on the intensity of immunoreactivity and, where relevant, the proportion of immunoreactive cells was established for each marker. RESULTS: Unsupervised two-dimensional hierarchical cluster analysis identified three distinct cluster groups (designated groups 1-3) with different marker profiles. There were significant survival differences between groups 1 and 2 (log rank = 11.48; P = 0.0007) and between groups 1 and 3 (log rank = 8.32; P = 0.0039). Multivariate analysis showed that the complete marker profile was independently the most significant prognostic factor (hazard ratio, 2.27; 95% confidence interval, 1.15-4.48; P = 0.004). CONCLUSIONS: This study has identified an immunohistochemical marker profile of colorectal cancer and showed that it is an independent indicator of prognosis in this type of cancer.

Adult↗

PubMed2005

The roles of heterogeneous nuclear ribonucleoproteins in tumour development and progression.

The heterogeneous nuclear ribonucleoproteins (hnRNP) are a family of proteins which share common structural domains, and extensive research has shown that they have central roles in DNA repair, telomere biogenesis, cell signaling and in regulating gene expression at both transcriptional and translational levels. Through these key cellular functions, individual hnRNPs have a variety of potential roles in tumour development and progression including the inhibition of apoptosis, angiogenesis and cell invasion. The aims of this review are to provide an overview of the multi functional roles of the hnRNPs, and how such roles implicate this family as regulators of tumour development. The different stages of tumour development that are potentially regulated by the hnRNPs along with their aberrant expression profiles in tumour tissues will also be discussed.

Animals↗

PubMed2005

Profiling cytochrome P450 expression in ovarian cancer: identification of prognostic markers.

PURPOSE: The cytochromes P450 are a multigene family of enzymes with a central role in the oxidative metabolism of a wide range of xenobiotics, including anticancer drugs and biologically active endogenous compounds. The purpose of this study was to define the cytochrome P450 profile of ovarian cancer and identify novel therapeutic targets and establish the prognostic significance of expression of individual cytochrome P450s in this type of cancer. EXPERIMENTAL DESIGN: Immunohistochemistry for a panel of 23 cytochrome P450s and cytochrome P450 reductase was done on an ovarian cancer tissue microarray consisting of 99 primary epithelial ovarian cancers, 22 peritoneal metastasis, and 13 normal ovarian samples. The intensity of immunoreactivity in each sample was established by light microscopy. RESULTS: In primary ovarian cancer, several P450s (CYP1B1, CYP2A/2B, CYP2F1, CYP2R1, CYP2U1, CYP3A5, CYP3A7, CYP3A43, CYP4Z1, CYP26A1, and CYP51) were present at a significantly higher level of intensity compared with normal ovary. P450 expression was also detected in ovarian cancer metastasis and CYP2S1 and P450 reductase both showed significantly increased expression in metastasis compared with primary ovarian cancer. The presence of low/negative CYP2A/2B (log rank = 7.06, P = 0.008) or positive CYP4Z1 (log rank = 6.19, P = 0.01) immunoreactivity in primary ovarian cancer were each associated with poor prognosis. Both CYP2A/2B and CYP4Z1 were also independent markers of prognosis. CONCLUSIONS: The expression profile of individual P450s has been established in ovarian cancer. Several P450s show increased expression in ovarian cancer and this provides the basis for developing P450-based therapeutics in ovarian cancer. Expression of CYP2A/2B or CYP4Z1 in primary ovarian cancer were independent markers of prognosis.

Adult↗

PubMed2005

Cytochrome p450 profile of colorectal cancer: identification of markers of prognosis.

PURPOSE: The cytochromes P450 (P450) are a multigene family of enzymes with a central role in the oxidative metabolism of a wide range of xenobiotics, including anticancer drugs, carcinogens, and endogenous compounds. The purpose of this study was to define the P450 profile of colorectal cancer and establish the prognostic significance of expression of individual P450s in colorectal cancer. EXPERIMENTAL DESIGN: Immunohistochemistry for a panel of 23 P450s was done on a colorectal cancer tissue microarray consisting of 264 primary colorectal cancers, 91 lymph node metastasis, and 10 normal colorectal samples. The intensity of immunoreactivity in each sample was established by light microscopy. RESULTS: The most frequently expressed form of P450 in normal colon was CYP3A4. In primary colorectal cancer, several P450s (CYP1B1, CYP2S1, CYP2U1, CYP3A5, and CYP51) were present at a significantly higher level of intensity compared with normal colon. P450 expression was also detected in lymph node metastasis and the presence of several P450s (CYP1B1, CYP2A/2B, CYP2F1, CYP4V2, and CYP39) in the lymph node metastasis strongly correlated with their presence in corresponding primary tumors. The presence of strong CYP51 (log-rank = 12.11, P = 0.0005) or strong CYP2S1 (log-rank = 6.72, P = 0.0095) immunoreactivity were associated with poor prognosis. CYP51 was also an independent marker of prognosis (P = 0.009). CONCLUSIONS: The expression of individual P450s has been established in colorectal cancer. Several P450s show increased expression in colorectal cancer. High expression of CYP51 or CYP2S1 were associated with poor prognosis and CYP51 is an independent marker of prognosis.

Aged↗

PubMed2005

Pregnenolone-16alpha-carbonitrile inhibits rodent liver fibrogenesis via PXR (pregnane X receptor)-dependent and PXR-independent mechanisms.

The effect of liver growth stimulation [using the rodent PXR (pregnane X receptor) activator PCN (pregnenolone-16alpha-carbonitrile)] in rats chronically treated with carbon tetrachloride to cause repeated hepatocyte necrosis and liver fibrogenesis was examined. PCN did not inhibit the hepatotoxicity of carbon tetrachloride. However, transdifferentiation of hepatic stellate cells and the extent of fibrosis caused by carbon tetrachloride treatment was significantly inhibited by PCN in vivo. In vitro, PCN directly inhibited hepatic stellate cell transdifferentiation to a profibrogenic phenotype, although the cells did not express the PXR (in contrast with hepatocytes), suggesting that PCN acts independently of the PXR. Mice with a functionally disrupted PXR gene (PXR-/-) did not respond to the antifibrogenic effects of PCN, in contrast with wild-type (PXR+/+) mice, demonstrating an antifibrogenic role for the PXR in vivo. However, PCN inhibited the transdifferentiation of PXR-/--derived mouse hepatic stellate cells in vitro, confirming that there is also a PXR-independent antifibrogenic effect of PCN through a direct interaction with hepatic stellate cells. These data suggest that the PXR is antifibrogenic in rodents in vivo and that a PXR-independent target for PXR activators exists in hepatic stellate cells that also functions to inhibit fibrosis.

Animals↗

PubMed2005

Mortalin is over-expressed by colorectal adenocarcinomas and correlates with poor survival.

Using comparative proteomic analysis we have identified over-expression of mortalin in colorectal adenocarcinomas. Mortalin, also known as mitochondrial heat-shock protein 70 (mhsp 70), is involved in cell cycle regulation with important roles in cellular senescence and immortalization pathways. It is known to bind to and inactivate wild-type tumour suppressor protein p53 and influences the Ras-Raf-MAPK pathway. By immunostaining a colorectal cancer tissue microarray linked to a patient database, we further found that mortalin over-expression correlates with poor patient survival and, in multivariate analysis, is independent of standard prognostic variables (p = 0.04). Our findings demonstrate that mortalin over-expression may predict outcome in colorectal cancer and suggest that this protein is involved in colorectal neoplasia. Our experimental approach emphasises the analytical power of combining proteomics with tissue microarray analysis in the context of a well-defined tumour database.

Adenocarcinoma↗

PubMed2005

An introduction to laser-based tissue microdissection techniques.

The development and application of laser-based tissue microdissection techniques has provided a major impetus to the sensitive and specific molecular analysis of solid tissues and tumors. This chapter provides an overview of the different laser-based microdissection systems and an introduction to the principles involved in the function and applications of these individual systems.

Animals↗

PubMed2005

Laser capture microdissection and PCR for analysis of human papilloma virus infection.

Human papilloma virus (HPV) infection is considered one of the main factors involved in the pathogenesis of endocervical adenocarcinoma. However, the cellular location of HPV in this type of tumor is controversial. We have developed a method to determine the presence of HPV type 16 in endocervical cancer cells using laser capture microdissection followed by DNA extraction and qualitative polymerase chain reaction. Our results show that HPV type 16 is present in endocervical adenocarcinoma cells.

Adenocarcinoma↗

PubMed2005

Cytochrome P450 1B1: a novel anticancer therapeutic target.

Cytochrome P450 (CYP)1B1 is overexpressed in tumor cells and is also recognized as a biomarker of the tumor phenotype. This review highlights the tremendous potential of this enzyme as a novel cancer therapeutic target. The range of therapeutic strategies including immunotherapeutics, CYP1B1-activated prodrugs and CYP1B1 inhibitors, that are currently being developed to exploit the presence and activity of CYP1B1 in tumor cells is outlined. The therapeutic strategy, which is at the most advanced stage of development, is a CYP1B1-based vaccine which has already successfully completed a Phase I clinical trial.

Antineoplastic Agents↗

PubMed2004

Matrix metalloproteinase/tissue inhibitors of matrix metalloproteinase phenotype identifies poor prognosis colorectal cancers.

PURPOSE: The matrix metalloproteinases (MMPs) are a family of proteolytic enzymes involved in tumor invasion; several individual members of which have been implicated in tumor prognosis. These enzymes and their physiologic inhibitors, the tissue inhibitors of matrix metalloproteinases (TIMPs), act in a coordinated manner to form an integrated system. Therefore, to understand their role in tumor invasion, it is necessary to evaluate them collectively. EXPERIMENTAL DESIGN: In this study all of the major members of the matrix metalloproteinase (MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, MMP-13, MT1-MMP and MT2-MMP)/tissue inhibitor of matrix metalloproteinase (TIMP-1, TIMP-2, and TIMP-3) system have been investigated by immunohistochemistry in a series (n = 90) of stage III (Dukes' C) colorectal cancers. An immunohistochemical score based on the intensity of immunoreactivity and proportion of immunoreactive cells was established for each MMP and TIMP. RESULTS: The MMP/TIMP profile defined by hierarchical cluster analysis of the immunohistochemical score identifies a distinct group of colorectal cancers with poor prognosis (log-rank test, 12.22, P = 0.0005). The median survival time of patients in this survival group was 18 months compared with a median survival of 49 months in the "good" survival group. Multivariate analysis showed that this profile was independently the most significant prognostic factor (P = 0.001). CONCLUSIONS: This study has identified that the MMP/TIMP profile is an independent indicator of poor prognosis in colorectal cancer.

Adenocarcinoma↗

PubMed2004

Gene expression profiling in non-small cell lung cancer: from molecular mechanisms to clinical application.

Non-small cell lung cancer (NSCLC) is the most common cause of premature death from malignant disease in western countries. A better understanding of the molecular mechanisms underlying NSCLC etiology, pathogenesis, and therapeutics will lead to improved clinical outcomes. Recent technological advances in gene expression profiling (in particular, with cDNA and oligonucleotide microarrays) allow the simultaneous analysis of the expression of thousands of genes. In this review, the technology of global gene expression profiling is discussed, and the progress made thus far with it in NSCLC is reviewed. A new molecular classification of NSCLC has been developed, which has provided important insights into etiology and pathogenesis. Other studies have found potential biomarkers for NSCLC that may be of use in diagnosis, screening, and assessing the effectiveness of therapy. Finally, advances have been made in the understanding of the molecular mechanisms of NSCLC progression and the molecular mechanisms of action of currently used cytotoxic drugs. This may facilitate the improvement of current therapeutics and the identification of novel targets. Taken together, these advances hold the promise of an improved understanding of the molecular biology of NSCLC and its treatment, which in turn will lead to improved outcomes for this deadly disease.

Biomarkers, Tumor↗

PubMed2004

Target validation of cytochrome P450 CYP1B1 in prostate carcinoma with protein expression in associated hyperplastic and premalignant tissue.

PURPOSE: To investigate the localization and distribution of cytochrome P450 CYP1B1 protein expression in patients diagnosed with prostate carcinoma compared to those with bladder carcinoma. To validate CYP1B1 as a molecular target for the development of selective cancer therapeutics for use in combination with radiation. METHODS AND MATERIALS: Prostatectomy specimens (n = 33) of moderate Gleason grade (3 + 3 and 3 + 4) were analyzed immunohistochemically for CYP1B1 protein expression using a specific monoclonal antibody for the enzyme. The intensity of CYP1B1 staining was assessed both semiquantitatively using visual scoring and quantitatively by spectral imaging microscopy using reference spectra and compared with bladder carcinoma (n = 22). RESULTS: CYP1B1 protein expression was present in 75% of prostate carcinomas (n = 27) compared to 100% of bladder carcinomas (n = 22). In both cases, CYP1B1 protein expression was heterogeneous and localized in the cytoplasm of the tumor cells but absent from the surrounding stromal tissue. CYP1B1 was also detected in premalignant prostatic intraepithelial neoplasia (n = 2, 100%), as well as noncancerous tissues, including benign prostatic hyperplasia (n = 27, 82%), metaplastic prostatic urothelium (n = 8, 100%), and hyperplastic prostatic urothelium (n = 14, 100%). Higher CYP1B1 protein expression in bladder vs. prostate carcinoma was confirmed by their corresponding average normalized absorbances (+/- standard deviation), measured as 1.40 +/- 0.44 and 0.55 +/- 0.09, respectively. Overall CYP1B1 staining intensity in prostate carcinoma was similar to that in prostatic intraepithelial neoplasia, benign prostatic hyperplasia, and hyper-/metaplastic urothelial tissue. No CYP1B1 was detected in normal prostate tissue. CONCLUSIONS: CYP1B1 is overexpressed in prostate carcinoma at a high frequency and is also detectable in the associated premalignant and hyperplastic tissue, implicating a possible link with malignant progression and CYP1B1 as a suitable target for therapy. Spectral imaging microscopy has highlighted differences in CYP1B1 protein expression between different cancers.

Aged↗

PubMed2004

Expression of Fhit, cell adhesion molecules and matrix metalloproteinases in atypical adenomatous hyperplasia and pulmonary adenocarcinoma.

Invasive parenchymal-type lung adenocarcinoma develops from atypical adenomatous hyperplasia (AAH), through an intermediate in situ stage of bronchioloalveolar carcinoma (BAC). We examined the expression of the putative tumour suppressor gene product Fhit, cell adhesion molecules CD44v6, E-cadherin and beta-catenin, and matrix metalloproteinase 2 and its inhibitor, TIMP-2, in a range of AAH lesions, BACs and invasive adenocarcinomas, to determine the changes in molecular expression associated with this form of neoplastic progression. Sections of formalin-fixed wax-embedded archival tissue were stained by standard Immunohistochemical techniques and scored semi-quantitatively, resulting in a grading of negative/low- or high-level staining. Fhit protein was retained at high levels in over 90% of AAH and 83% of BAC, but was found in only 6% of stromally invasive tumours (p < 0.0001). CD44v6 staining was high-level in 64% of AAH but fell to 26% in stromally invasive tumour (p = 0.007). E-cadherin and beta-catenin showed the opposite, with more high-level staining as adenocarcinoma developed (p < 0.001). High-level MMP-2 and TIMP-2 expression was relatively infrequent in AAH (32% and 40% respectively), rose in BAC (89% each) but fell in stromally invasive tumour (31% and 17% respectively) (p < 0.01). Unlike in central bronchial carcinogenesis, loss of Fhit expression is a relatively late event in this putative progression of lung adenocarcinogenesis, and has potential as a surrogate marker of invasion, which could be of value in screening patients for lung cancer. Loss of CD44v6 expression follows the convention of falling adhesion molecule expression as malignancy develops. Increased expression of E-cadherin and beta-catenin may reflect increased cell-cell contact as tissue architecture changes in the transition from AAH to adenocarcinoma. Loss of MMP-2 and TIMP-2 in stromally invasive tumour may reflect a particular role for MMP-2 at the BAC stage, with later down-regulation of this particular enzyme.

Acid Anhydride Hydrolases↗

PubMed2004

The candidate oncogene ZNF217 is frequently amplified in colon cancer.

In this study we have defined the changes in gene copy number of the candidate oncogene ZNF217 during colon cancer development and progression. This gene is mapped to chromosome 20q and lies within 20q13.2, a region which we have previously shown to be highly amplified in colorectal cancer by comparative genomic hybridization. The gene copy number of ZNF217 was assessed in 100 colon carcinomas (19 Dukes' A, 42 Dukes' B and 39 Dukes' C), 13 colonic adenomas and 10 normal colon samples. DNA extracted from laser microdissected cells was amplified by multiplex real-time PCR at two distinct gene loci--ZNF217 and beta-globin (control gene)--on an ABI7700 sequence detection system. Of the 100 colon cancers studied, 61 showed some level of amplification of ZNF217, 15 had loss of ZNF217, while 24 were diploid. All the adenomas except one were diploid. In this study we have found that ZNF217 amplification is a frequent event in colon cancer and that the extent of its amplification varies markedly between tumours (range 3-13 copies). There was a trend toward poorer survival in patients whose cancers had either gain or loss of ZNF217.

Adenoma↗

PubMed2004

Cytochrome P450 enzymes: novel options for cancer therapeutics.

The concept of overexpression of individual forms of cytochrome P450 enzymes in tumor cells is now becoming well recognized. Indeed, a growing body of research highlights the overexpression of P450s, particularly CYP1B1, in tumor cells as representing novel targets for anticancer therapy. The purpose of this review is to outline the novel therapeutic options and opportunities arising from both enhanced endogenous expression of cytochrome P450 in tumors and cytochrome P450-mediated gene therapy.

Antineoplastic Agents↗

PubMed2004

Vitamin D receptor, HER-2 polymorphisms and risk of prostate cancer in men with benign prostate hyperplasia.

OBJECTIVE: Prostate cancer (PRCa) is one of the most common causes of cancer death in men and determinants of PRCa risk remain largely unidentified. Benign prostatic hyperplasia (BPH) is found in the majority of ageing men and has been associated with PRCa. Many candidate genes have been suggested to be involved in PRCa, such as those that are central to cellular growth and differentiation in the prostate gland. The vitamin D receptor (VDR) and HER-2 protooncogene have been shown to be involved in the regulation of cell proliferation and differentiation in prostate cells. Genetic variations of these genes could be useful to detect BPH patients that have a higher risk of developing PRCa. This study used a case-control design to assess the predictive value of 3 polymorphisms in VDR (TaqI and FokI) and HER-2 (Val655Ile) to determine the risk of developing PRCa in patients with BPH. METHODS: Polymorphisms were detected by RFLP analysis. The study evaluated 28 patients who presented with PRCa at least 6 years after the diagnosis of BPH and 56 matched patients with BPH who did not progress to PRCa over a comparable period. The study was carried out in University of Aberdeen, Foresterhill, Aberdeen, United Kingdom in the year 2002. RESULTS: Among the case group, 89% had a TT TaqI genotype, whereas 57% of control had this genotype (odds ratio [OR] = 5.16, 95% confidence interval [CI] = 1.46-18.22). A similar pattern was seen for the FokI genotype, although this was not statistically significant (OR = 2.33, 95% CI = 0.86-6.29). The frequency of the HER-2 Ile/Ile genotype was higher in cases (79%) compared to control subjects (66%), although this was not statistically significant (OR = 1.94, 95% CI = 0.67-5.63). CONCLUSION: This study shows that the VDR TaqI polymorphism is associated with a group of men with BPH who are at an increase risk of PRCa, providing a potential tool to assist prediction strategies for this important disease.

Case-Control Studies↗