Biomedical subjects

Vivi Ann Flørenes

Publications and source records attributed to Vivi Ann Flørenes.

At least 19 recordsLinked to original sources

PubMed2007

Nuclear expression of survivin is associated with improved survival in metastatic ovarian carcinoma.

BACKGROUND: Inhibitor of apoptosis proteins (IAPs) mediate cancer cell survival and chemoresistance. The expression of XIAP, Survivin, and Livin in ovarian carcinoma was analyzed. METHODS: Effusions (106) were analyzed for XIAP, Survivin, and Livin expression using immunoblotting. Effusions (220), corresponding primary tumors (60), and solid metastases (103) were further immunohistochemically analyzed for XIAP and Survivin expression. The results were analyzed for association with anatomic site, clinicopathologic parameters, and survival. RESULTS: Immunoblotting showed frequent expression of XIAP and Survivin, and no expression of Livin. Immunohistochemistry showed cytoplasmic XIAP expression in 208 of 220 (94%) effusions, 50 of 60 (83%) primary tumors, and 87 of 103 (84%) solid metastases, with a significantly higher staining extent in effusions (P < .001). Cytoplasmic Survivin was found in 194 of 220 (88%) effusions, 55 of 60 (92%) primary tumors, and 102 of 103 (99%) solid metastases, with a significantly higher cytoplasmic staining extent in solid metastases (P = .018 and P = .006 compared with primary tumors and effusions, respectively). Nuclear Survivin was expressed in 159 of 220 (72%) effusions, 54 of 60 (90%) primary carcinomas, and 96 of 103 (93%) solid metastases (P > .05). For patients with prechemotherapy effusions, higher nuclear Survivin expression correlated with better progression-free (P = .0003) and overall (P = .002) survival in univariate survival analysis. Nuclear Survivin expression was found to be an independent predictor of progression-free survival (P = .004). CONCLUSIONS: XIAP and Survivin, but not Livin, are frequently expressed in ovarian carcinoma. XIAP and cytoplasmic Survivin are up-regulated in effusions and solid metastases, respectively, possibly mediating survival at these sites. Nuclear Survivin expression predicts better outcome in prechemotherapy patients.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Gene expression signatures differentiate ovarian/peritoneal serous carcinoma from diffuse malignant peritoneal mesothelioma.

PURPOSE: Ovarian/primary peritoneal serous carcinoma (OC/PPC) and diffuse peritoneal malignant mesothelioma (DMPM) are highly aggressive tumors that are closely related morphologically and histogenetically. It remains unclear whether both tumors are molecularly distinct neoplasms. The current study compared global gene expression patterns in OC/PPC and DMPM. EXPERIMENTAL DESIGN: Ten OC/PPC and five DMPM effusions were analyzed for gene expression profiles using the Affymetrix U133 Plus 2 arrays and the dCHIP analysis program. Differentially expressed candidate genes were validated using quantitative real-time PCR and immunohistochemistry. RESULTS: Unsupervised hierarchical clustering using all 54,675 genes in the array classified the samples into two groups: DMPM specimens versus OC/PPC specimens. A total of 189 genes that were differentially expressed in these two groups were selected based on statistical significance. Genes overexpressed in DMPM (n = 68) included calretinin, vitronectin, claudin 15, alpha4 laminin, hyaluronan synthase 1, cadherin 11, RAB7, v-maf, and the epidermal growth factor-containing fibulin-like extracellular matrix protein 1. Genes overexpressed in OC/PPC (n = 121) included insulin-like growth factor II (IGF-II); IGF-II binding protein 3; cyclin E1; folate receptors 1 and 3; RAB25; MUC4; endothelin-1; CD24; kallikreins 6, 7, and 8; claudins 3, 4, and 6; Notch3; and MMP-7. Quantitative real-time PCR validated the differential expression of 13 genes, and immunohistochemistry confirmed the differences for four gene products. CONCLUSIONS: Expression profiling separates OC/PPC from DMPM and identifies a number of genes that are differentially expressed in these tumors. The molecular signatures unique to OC/PPC and DMPM should provide a molecular basis to study both tumors and new potential markers for facilitating their differential diagnosis.

Carcinoma↗

PubMed2006

Expression of HLA-G in malignant mesothelioma and clinically aggressive breast carcinoma.

The aim of the present study was to evaluate HLA-G expression in breast carcinoma and malignant mesothelioma (MM). Malignant breast carcinoma effusions (46) and corresponding solid tumors (39) and 104 MM (26 effusions, 78 solid tumors) were analyzed using immunohistochemistry (IHC). HLA-G protein and mRNA expression were further studied using immunoblotting (IB) and RT-PCR. HLA-ABC expression was analyzed using flow cytometry (FCM). IHC showed predominantly focal HLA-G expression in 12 of 46 (26%) breast carcinoma effusions and 16 of 39 (41%) solid lesions. In MM, 20 of 78 (26%) solid lesions and 14 of 26 (54%) effusions were focally HLA-G positive. Expression in MM was higher in effusions (p=0.008). IB showed more frequent HLA-G expression in MM compared with breast carcinoma effusions, while RT-PCR showed HLA-G mRNA expression in both tumors. FCM showed conserved HLA-ABC expression in 15 of 15 effusions. Breast cancer patients with HLA-G-positive tumor cells had shorter disease-free survival (mean 37 vs 85, median 25 vs 31 months), though not significantly (p=0.14). In conclusion, HLA-G is focally expressed in MM and breast carcinoma, while HLA-ABC expression is conserved. However, the up-regulated expression of HLA-G in MM effusions and its possible association with shorter disease-free survival in advanced stage of breast carcinoma suggest a possible role in immune response evasion in some tumors.

Adenocarcinoma↗

PubMed2006

Proteomic analysis of malignant ovarian cancer effusions as a tool for biologic and prognostic profiling.

PURPOSE: Malignant epithelial ovarian cancer effusions are important in disease dissemination and clinical outcome. The identification of biochemical events active in effusions may improve our identification and application of targeted therapeutics. EXPERIMENTAL DESIGN: Archival effusion samples for which outcome information was known were studied. Clinical variables were comparable between these groups. Two cohorts of patients with malignant effusion were assessed: those with effusion at presentation (Tap1) or at first recurrence (Tap2). Expression and activated fraction of selected signaling proteins were quantitated on serial protein microarrays using validated antibodies. Proteomic results and clinical variables were analyzed by univariate analysis followed by Cox proportional hazards model analysis. RESULTS: Malignant effusions (>80% malignant cells) were distinguished from benign effusions by higher expression of AKT, activated extracellular signal-regulated kinase, activated (P < or = 0.001) and total cAMP-responsive element binding protein (P = 0.01), and JNK (P = 0.03). Malignant pleural effusions could not be differentiated from ascites by signaling profiles. Both had signal expression clusters for survival, proliferation and metastasis, and injury pathways. Cox proportional hazards model analysis revealed high p38 and pEGFR/EGFR ratio as jointly associated with poor survival in Tap1 cases (both P < or = 0.002). Phospho-JNK quantity was associated with worse outcome in Tap2 patients (P = 0.004), when taking other factors into consideration. CONCLUSIONS: Proliferation, survival, and apoptosis signaling dysregulation can be identified in ovarian cancer effusion samples. Biochemical characterization of clinical effusions may provide either predictive and/or correlative information on patient outcome from which to further understand the mechanisms of effusion development and target clinical intervention.

Apoptosis↗

PubMed2006

Pax-5 expression in nonhematopoietic tissues.

We evaluated 123 formalin-fixed, paraffin-embedded samples, including neuroendocrine tumors, adult brain, mesonephric tissues, and from various other sites. A pre-B lymphoma cell line, Daudi, and a small cell carcinoma cell line, NCL-H128, were evaluated by Western blot. All tissues were immunostained by mouse monoclonal anti-Pax-5 antibody by using standard, synthetic polymer-based detection methods. Our study describes for the first time distribution of Pax-5 in adult brain tissue, including periaqueductal gray matter of the midbrain, area postrema of the medulla oblongata, and occasional cells of the spinal trigeminal nucleus (caudal nucleus). We confirm that Pax-5 is expressed regularly in poorly differentiated neuroendocrine tumors but never in well-differentiated classic carcinoid tumors. Pax-5 expression also was found readily in benign and malignant mesonephric tissues and focally in müllerian duct-derived tissues and tumors. Expression of Pax-5 in the Daudi and NCL-H128 cell lines was confirmed by Western blot. Together, these results are important for correct interpretation of results in immunophenotyping of undifferentiated tumors, for diagnosis of mesonephric carcinoma, and, potentially, for correct classification of neuroendocrine tumors in small biopsy samples.

Adult↗

PubMed2005

The AP-2gamma transcription factor is upregulated in advanced-stage ovarian carcinoma.

OBJECTIVE: To analyze the expression of the AP-2gamma transcription factor in ovarian borderline tumors, early-stage ovarian carcinoma and advanced-stage ovarian carcinoma, and to evaluate its prognostic role in advanced-stage tumors. METHODS: Sections from 14 normal ovaries, 75 borderline tumors, 22 FIGO stage I invasive ovarian carcinomas, and 306 advanced-stage (FIGO stages II-IV) ovarian carcinomas (42 primary tumors, 62 solid metastases, 202 effusions) were evaluated for expression of the transcription factor AP-2gamma using immunohistochemistry. Sixty-three effusions and two cell lines (SKOV-3 and OVCAR-3) were additionally studied using immunoblotting. The prognostic role of AP-2gamma in advanced-stage carcinomas was analyzed. RESULTS: AP-2gamma was detected in the nucleus of tumor cells in 28/75 (37%) borderline tumors, 13/22 (59%) FIGO stage I carcinomas, and 255/306 (83%) advanced-stage carcinomas (P < 0.001, Chi-square test). Benign ovaries were uniformly negative. Expression was largely limited to carcinoma cells in effusions. Solid lesions and effusions from advanced-stage carcinomas showed comparable expression. Immunoblotting showed AP-2gamma expression in 59/61 effusions and both cell lines. AP-2gamma expression did not correlate with survival. CONCLUSIONS: AP-2gamma expression is upregulated in advanced-stage ovarian carcinoma compared to early-stage carcinomas, borderline tumors, and the ovarian surface epithelium, and AP-2gamma is specifically localized to cancer cells in effusions, suggesting a role in tumor progression. The lack of predictive value for this transcription factor in advanced-stage disease may be related to its frequent expression.

Adult↗

PubMed2005

Variation in gene expression patterns in effusions and primary tumors from serous ovarian cancer patients.

BACKGROUND: While numerous studies have characterized primary ovarian tumors, little information is available regarding expression patterns of metastatic sites of this cancer. To define sets of genes that distinguish primary and metastatic ovarian tumors, we used cDNA microarrays to characterize global gene expression patterns in 38 effusions (28 peritoneal, 10 pleural) and 8 corresponding primary ovarian tumors, and searched for associations between expression patterns and clinical parameters. RESULTS: We observed multidimensional variation in expression patterns among the cancers. Coordinate variation in expression of genes from two chromosomal regions, 8q and 19q, was seen in subsets of the cancers indicating possible amplifications in these regions. A set of 112 unique genes of known function was differentially expressed between primary tumors and effusions using supervised analysis. Relatively few differences were seen between effusions isolated from the pleural and peritoneal cavities or between effusions from patients diagnosed with stage III and stage IV cancers. A set of 84 unique genes was identified that distinguished high from lower grade ovarian cancers. The results were corroborated using immunocytochemistry, mRNA in situ hybridization, and immunoblotting. CONCLUSION: The extensive variation in expression patterns observed underscores the molecular heterogeneity of ovarian cancer, but suggests a similar molecular profile for ovarian carcinoma cells in serosal cavities.

Adult↗

PubMed2005

Phorbol ester phorbol-12-myristate-13-acetate promotes anchorage-independent growth and survival of melanomas through MEK-independent activation of ERK1/2.

The phorbol ester, phorbol-12-myristate-13-acetate (PMA), an activator of PKCs, is known to stimulate the in vitro growth of monolayer cultures of normal human melanocytes whereas it inhibits the growth of most malignant melanoma cell lines. We examined the effect of PMA on proliferation and survival of melanoma cells grown as multicellular aggregates in suspension (spheroids), and aimed to elucidate downstream targets of PKC signaling. In contrast to monolayer cultures, PMA increased cell proliferation as well as protected melanoma cells from suspension-mediated apoptosis (anoikis). Supporting the importance of PKC in anchorage-independent growth, treatment of anoikis-resistant melanoma cell lines with antisense oligonucleotides against PKC-alpha, or the PKC inhibitor Gö6976, strongly induced anoikis. PMA induced activation of ERK1/2, but this effect was not prevented by the MEK inhibitors PD98059 or by U0126. Whereas PD98059 treatment alone led to marked activation of the pro-apoptotic Bim and Bad proteins and significantly increased anoikis, these effects were clearly reversed by PMA. In conclusion, our results indicate that the protective effect of PMA on anchorage-independent survival of melanoma cells at least partly is mediated by MEK-independent activation of ERK1/2 and inactivation of downstream pro-apoptotic effector proteins.

Anoikis↗

PubMed2005

Expression patterns of cell cycle components in sporadic and neurofibromatosis type 1-related malignant peripheral nerve sheath tumors.

The molecular biology underlying the development of highly malignant peripheral nerve sheath tumors (MPNSTs) remains mostly unknown. In the present study, the expression pattern of 10 selected cell cycle components is investigated in a series of 15 MPNSTs from patients with (n = 9) or without (n = 5) neurofibromatosis type 1 (NF1). Thirteen tumors did not express the cyclin-dependent kinase inhibitor, p16(INK4A), an observation that was related to homozygote gene deletions in three tumors, heterozygote deletions in five, and gross gene rearrangements in five. The absence of protein expression in the tumors with one seemingly intact allele was not caused by promoter hypermethylation of p16(INK4A) or p14(ARF). All tumor samples expressed normal sized RB1, cyclin D3, CDK2, CDK4, p21(CIP1), and p27(KlP1) proteins, and only a single tumor showed an aberrant protein band for one of these proteins, p21(CIP1). Cyclin D1 was absent in four tumors; all except one tumor showed expression of TP53 protein, and three of nine MPNSTs had expression of normal-sized MDM2. In conclusion, this study shows that the vast majority of MPNSTs had gross rearrangements of the p16(INK4A) gene, explaining the absence of the encoded protein in the same tumors. The level of expression was equally distributed between the familial (NF1) and sporadic cases, although it should be noted that the 2 cases with p16(INK4A) expression were sporadic. The data imply that the complete absence of p16(INK4A) is sufficient for activation of the cell cycle in most MPNSTs; thus, it is not necessary for tumor proliferation to further stimulate the cycle through alteration of other central components.

Adult↗

PubMed2005

Expression of activated Akt and PTEN in malignant melanomas: relationship with clinical outcome.

Our purpose was to analyze, by immunohisto-chemistry, the expression of activated serine-threonine protein kinase B (p-Akt) and phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in benign nevi and primary and metastatic melanomas and to correlate the expression level with clinical variables. We observed cytoplasmic and/or nuclear expression of p-Akt in 22 (54%) of 41 benign nevi, 112 (71.3%) of 157 primary tumors, and 50 (71%) of 70 metastases. Cytoplasmic PTEN staining was observed in 0 (0%), 152 (87.7%), and 64 (90%) of 41 nevi, 162 primary tumors, and 71 metastases, respectively. A significant positive correlation was seen between PTEN and p-Akt cytoplasmic expression (P < .001) in primary melanomas. Cytoplasmic p-Akt expression showed a positive association with cyclin A in superficial spreading (P = .038) but not in nodular (P = .22) melanomas. Cytoplasmic p-Akt and PTEN expression did not have an impact on disease-free and overall survival, but complete lack of nuclear p-Akt expression was a predictor of shorter disease-free survival (P = .025) for patients with superficial spreading melanoma.

Adult↗

PubMed2004

Granulin-epithelin precursor is a novel prognostic marker in epithelial ovarian carcinoma.

BACKGROUND: The granulin-epithelin precursor (GEP) was preferentially expressed in invasive ovarian tumor epithelium specimens compared with specimens of borderline ovarian tumors. The objective of the current study was to evaluate the anatomic site-related and cellular expression of GEP and its association with clinicopathologic parameters and survival in patients with advanced-stage ovarian carcinoma. METHODS: Effusions (n = 190), corresponding primary tumor specimens (n = 64), and specimens of metastatic lesions (n = 125) were analyzed using immunohistochemistry with a specific polyclonal antipeptide antibody. In addition, 36 effusions were analyzed using immunoblotting. RESULTS: GEP was detected in tumor cells in 171 of 190 (90%) effusions and demonstrated both focal membrane and cytoplasmic localization. Mesothelial cells were often GEP positive (81%). GEP was found in carcinoma cells in 180 of 189 (95%) tumor biopsy specimens, with stromal and endothelial cell expression in 93 of 180 (52%) and 124 of 185 (67%) specimens, respectively. Lower GEP expression in stromal cells was observed in metastases sampled during or after chemotherapy (P = 0.034). The presence of GEP-positive stromal cells in untreated primary tumor specimens correlated with worse overall survival (P = 0.014). Significantly more frequent GEP expression was observed in tumor cells of both primary (P = 0.002) and metastatic (P < 0.001) tissue specimens compared with malignant effusions. CONCLUSIONS: GEP expression was observed in primary and metastatic epithelial ovarian carcinoma specimens, with down-regulated expression in tumor cells of malignant effusions. The poor outcome associated with stromal GEP expression suggests a prognostic role for this growth factor in ovarian carcinoma.

Adenocarcinoma, Clear Cell↗

PubMed2004

Expression of the nerve growth factor receptors TrkA and p75 in malignant mesothelioma.

The objective of the present report was to study the expression of the low affinity nerve growth factor (NGF) receptor p75 and of the activated high-affinity NGF receptor TrkA in malignant mesothelioma (MM). In addition, to analyze whether expression of these receptors is site-related (pleural versus peritoneal MM, solid lesions versus effusions). Sections from 81 MM (57 biopsies, 24 effusions) were analyzed. Sixty-one mesotheliomas were of pleural origin, while the remaining 20 were peritoneal. Effusion specimens consisted of 6 peritoneal and 18 pleural effusions, while biopsies consisted of 14 peritoneal and 43 pleural lesions. Specimens were immunohistochemically stained using antibodies against p75 and phospho-TrkA (p-TrkA). Six effusions were additionally analyzed for p-TrkA expression using immunoblotting (IB). p-TrkA membrane expression (66/81 specimens; 81%) was by far more frequent than that of p75 (26/81 specimens; 32%). In addition, p-TrkA expression was significantly higher in peritoneal MM compared to their pleural counterparts (20/20 versus 46/61 positive tumors; P = 0.014). p-TrkA membrane expression was marginally higher in effusions (P = 0.058), while the opposite was true for p75 membrane expression (P = 0.008) and p-TrkA cytoplasmic expression (P = 0.003). In conclusion, our results document for the first time frequent expression of p-TrkA and lower expression of p75 in MM, in agreement with the biological aggressiveness of this tumor. The enhanced expression of p-TrkA in peritoneal MM, tumors that appear in younger patients, and in effusions as compared to solid tumors, suggest that p-TrkA plays a significant role in the biology of this disease and may aid in defining tumor progression in this setting.

Adult↗

PubMed2004

Altered expression and activation of the nerve growth factor receptors TrkA and p75 provide the first evidence of tumor progression to effusion in breast carcinoma.

The aim of this study was to characterize phenotypic alterations along the progression of breast carcinoma from primary tumor to pleural effusion through analysis of the expression of nerve growth factor (NGF) and its receptors phospho-TrkA (p-TrkA activated receptor) and p75. Sections from 42 malignant pleural effusions from breast cancer patients and 65 corresponding solid tumors (34 primary, 31 metastatic) were evaluated for protein expression of the activated p-TrkA receptor. The majority of lesions were additionally studied for NGF and p75 expression. Six effusions and four breast carcinoma cell lines were studied for expression of p-TrkA using immunoblotting (IB). Membrane expression of p-TrkA was high in carcinoma cells in effusions (39/42, 93%) and locoregional recurrences (12/13, 92%), with significantly lower expression in both primary tumors (14/34, 41%) and lymph node metastases (8/18, 44%), respectively (p < 0.001 for effusions vs. primary tumors; p = 0.001 for effusions vs. lymph nodes). In contrast, p75 expression was less frequent in effusions compared to both primary tumors and lymph node metastases, significantly so for the latter (p = 0.019). NGF expression was comparable at all sites, but its expression in tumor cells in effusions (7/21 cases) was limited to cases in which time to progression (TTP) to effusion occurred within 5 years or less from primary operation. In univariate analysis of survival, mean and median TTP were 6.3 and 6 years for NGF-negative effusions, compared to 3 and 4 years for NGF-positive cases (p = 0.013). IB confirmed expression of p-TrkA in five of six effusions, while all four breast cancer cell lines were p-TrkA-negative. Our data provide the first documented evidence of molecular events that occur along tumor progression of breast carcinoma from primary tumors to effusion. The almost universal expression of p-TrkA in cancer cells in effusions and late recurrences is in full agreement with our recent report linking this factor with poor prognosis in ovarian cancer. Furthermore, the rapid progression to effusion in cases showing NGF expression in tumor cells underscores the aggressive clinical behavior of tumors that are able to utilize this pathway in an autocrine manner.

Adult↗

PubMed2004

Deacetylase inhibition in malignant melanomas: impact on cell cycle regulation and survival.

In the present study the deacetylase inhibitor trichostatin A (TSA) was used to elucidate the effect of protein acetylation on cell cycle progression and survival in seven human malignant melanoma cell lines. It was shown that TSA treatment led to a transient G(2)/M phase delay and accumulation of unphosphorylated retinoblastoma protein (pRB) in all cases. TSA significantly induced protein expression of the cyclin-dependent kinase inhibitor p21(WAF1/CIP1) in a dose-dependent manner in all cell lines including those not expressing p21(WAF1/CIP1) constitutively, whereas the levels of both wild-type and mutated p53 protein were reduced. The effect on p53 was not a direct result of inhibition of extracellular signal-regulated kinase-1/2 (ERK1/2) activation by TSA, as treatment of the cells with the mitogen-activated protein kinase/extracellular signal-regulated kinase kinase-1 (MEK1) inhibitor PD98059 did not result in decreased p53 protein level. Furthermore, TSA treatment led to reduction in cyclin D1 whereas cyclin D3 accumulated, the latter due to increased protein stability. Similarly, cyclin A protein was reduced whereas cyclin E level was elevated. The effect on p27(Kip1), CDK4 and CDK2 was only marginal. In all the examined cell lines, TSA treatment resulted in a profound induction of apoptosis and cleavage of poly-(ADP-ribose)-polymerase (PARP) indicative of caspase activity. Similarly, TSA-mediated apoptosis was reversed by the caspase-inhibitor z-vad-fmk. Altogether, these results suggest that p21(WAF1/CIP1) in melanomas is silenced by deacetylation, and furthermore that inhibition of deacetylation may have potential in anticancer therapy of melanoma patients.

Apoptosis↗

PubMed2004

Expression of activated TrkA protein in melanocytic tumors: relationship to cell proliferation and clinical outcome.

We evaluated expression of activated nerve growth factor receptor tyrosine kinase (p-TrkA) by immunohistochemical analysis in 152 primary and 64 metastatic human melanoma biopsy specimens and 8 nevi. Membranous, cytoplasmic, and/or nuclear expression of p-TrkA was seen in 54.6% of primary melanomas and 30% of metastases. Membranous p-TrkA was detected in 21.7% of primary and 14% of metastatic melanomas and cytoplasmic immunoreactivity in 28.9% of primary tumors and in 22% of metastases. Significantly fewer metastases than primary tumors expressed nuclear p-TrkA (16% vs 39.5%; P = .006). A significantly higher percentage of nodular than superficial spreading melanomas expressed membranous (40% vs 11%; P < .0001) p-TrkA. Nevi expressed no membranous or cytoplasmic p-TrkA; 63% showed nuclear reactivity. p-TrkA expression varied significantly with thickness of primary tumors (lower expression in thinner lesions: membranous, P = .004; cytoplasmic, P = .001; nuclear, P = .031). An association between ulceration and membranous (P = .054), cytoplasmic (P < .0001), and nuclear (P = .022) p-TrkA expression was found. Membranous p-TrkA significantly predicted decreased overall survival (P = .002). A significant association between membranous p-TrkA and cyclin A (P = .004) and Ki-67 (P < .0001) and between cytoplasmic p-TrkA and cyclin A (P < .0001), Ki-67 (P = .004), and cyclin D3 (P = .027) was found. p-TrkA had no effect on MAPK(ERK1/2) activation. A significant inverse association between cytoplasmic beta-catenin and cytoplasmic p-TrkA levels (P = .006) and between nuclear p-TrkA and cytoplasmic E-cadherin (P = .022) was seen. We present the first evidence of a role for TrkA activation in a subset of melanomas as a predictor of an aggressive phenotype and poor outcome.

Adult↗

PubMed2003

Expression of activated extracellular signal-regulated kinases 1/2 in malignant melanomas: relationship with clinical outcome.

PURPOSE: The purpose of the present work was to analyze the protein expression of activated extracellular signal-regulated kinases 1 and 2 (ERK1/2) in a panel of superficial spreading (SSM) and nodular (NM) primary and metastatic melanomas, and to correlate the expression level with clinicopathological parameters. EXPERIMENTAL DESIGN: Expression of activated ERK1/2 was examined by immunohistochemistry in 172 primary melanomas (108 SSM and 64 NMs), 67 metastatic lesions, and in 41 benign nevi. RESULTS: Fifty four percent of primary and 33% of metastatic melanomas expressed variable levels of activated ERK1/2. No immunoreactivity was detected in benign nevi. In 21% of the primaries only cytoplasmic expression was detected, whereas 3% and 30% showed positive immunoreactivity in either nucleus or cytoplasm and nucleus, respectively. Activated ERK1/2 expression varied significantly with the thickness of superficial spreading melanomas, with lower expression in thinner lesions (P = 0.016). A significant correlation between activated ERK1/2 and cyclin D1 (P = 0.031) in nodular, as well as between activated ERK1/2 and cyclin D3 (P = 0.030) in SSMs were observed. The protein level of p27(Kip1) correlated with activated ERK1/2 (P = 0.048) in the nucleus. Furthermore, a strong inverse correlation between activated ERK1/2 and membrane-bound beta-catenin (P = 0.004) in nodular melanomas was revealed. Activation of ERK1/2 did not have any impact on relapse-free or overall survival. CONCLUSION: Our results suggest that activation of ERK1/2 may be involved in cell cycle regulation in SSMs. Moreover, the inverse association between membrane-bound beta-catenin and ERK1/2 in NMs suggest that ERK1/2 activation may play a role in decreasing homotypic interactions through destabilization of beta-catenin.

Cell Cycle Proteins↗

PubMed2003

Reduced beta-catenin expression in the cytoplasm of advanced-stage superficial spreading malignant melanoma.

PURPOSE: The purpose of the present work was to analyze the expression of beta-catenin in a panel of superficial and nodular spreading primary and metastatic melanomas, and to correlate the level of immunohistochemical staining to clinicopathological parameters. EXPERIMENTAL DESIGN: Expression of beta-catenin was examined by immunohistochemistry in 106 superficial and 58 nodular spreading primary melanomas, as well as in 66 metastatic lesions. RESULTS: Membrane-associated staining was detected in nearly all of the cases, and no association to clinical parameters could be revealed. When cytoplasmic localization of the protein was recorded, a significant higher fraction of the superficial than the nodular spreading primary lesions expressed the protein in the majority of the cells (P < 0.0001). Interestingly, metastatic lesions from superficial melanomas demonstrated down-regulated expression of the protein, and in agreement with this a significant inverse correlation between protein expression and the vertical thickness of the primary lesion was detected (P = 0.012). Furthermore, a significant correlation between cytoplasmic localization and disease-free survival (P = 0.0006) was revealed, but beta-catenin did not have any significant impact on overall survival for this group of patients (P = 0.0824). No association was detected between beta-catenin expression and clinicopathological parameters in the nodular subgroup of melanomas, indicating that the protein may play different roles in the malignant progression of the two main types of melanomas. CONCLUSION: In summary, we hypothesize that cytoplasmic beta-catenin has a protective role in early melanoma development.

Adult↗

PubMed2003

Expression and activation of the nerve growth factor receptor TrkA in serous ovarian carcinoma.

PURPOSE: The purpose is to analyze the possible correlation between expression and activation of the high-affinity nerve growth factor (NGF) receptor TrkA, cell cycle protein expression, and disease outcome in serous ovarian carcinoma. In addition, we wished to study the possible link between expression of NGF, a novel angiogenic factor and its receptor TrkA, and the expression of factors involved in angiogenesis in effusions and solid tumors. EXPERIMENTAL DESIGN: Sections from 80 malignant effusions and 65 corresponding solid tumors were evaluated for protein expression of NGF, TrkA, and phospho-TrkA (p-TrkA). Effusions were additionally studied for expression of p53, p21(WAF1/CIP1), Ki-67, and the M(r) 85,000-cleaved fragment of poly(ADP-ribose) polymerase (p85-PARP) using immunohistochemistry (IHC). Thirty-two effusions were studied for TrkA, p-TrkA, p53, and p21(WAF1/CIP1) expression using immunoblotting. mRNA expression of basic fibroblast growth factor (bFGF), interleukin 8, and vascular endothelial growth factor (VEGF) was studied in 63 effusions and all solid tumors using in situ hybridization. Protein expression of bFGF, interleukin 8, and VEGF was additionally studied in 30 effusions using IHC. RESULTS: NGF, TrkA, and p-TrkA were expressed in carcinoma cells in effusions in 60 of 80 (75%), 64 of 80 (80%), and 15 of 80 (19%) specimens, respectively. In solid tumors, p-TrkA expression was more frequent (52 of 65 tumors; 80%) and was accompanied by p-TrkA expression in endothelial cells. NGF colocalized with bFGF protein (P = 0.016) and mRNA (P = 0.032) in effusions, and with VEGF (P < 0.001) and bFGF (P = 0.008) in solid tumors. In survival analysis, expression of p85-PARP (P = 0.017) and cytoplasmic TrkA (P < 0.001) in effusions predicted better outcome, whereas membrane expression of p-TrkA in solid tumors correlated with poor survival (P = 0.004). Diffuse expression of p53 and Ki-67 was often seen using IHC, whereas p21(WAF1/CIP1) and p85-PARP expression was infrequent and focal. None of these correlated with NGF or TrkA expression or activity. CONCLUSIONS: Coexpression of NGF with molecules involved in angiogenesis and p-TrkA expression in endothelial cells suggest that the proangiogenic role attributed to NGF in vitro and in vivo may be relevant in clinical cancer. Expression of p85-PARP as a marker of apoptosis and cytoplasmic expression of TrkA (probably representing nonglycosylated receptor) predict better outcome, whereas p-TrkA activation correlates with poor outcome in advanced stage serous ovarian carcinoma.

Adult↗