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Molecular profiling of exhaled breath condensate in respiratory diseases.

BACKGROUND: Respiratory disorders, , continue to pose a major global health burden. Their complexity and heterogeneity challenge accurate diagnosis, effective monitoring, and therapeutic decision-making. Exhaled breath condensate (EBC) provides a reliable, non-invasive means of sampling the molecular environment of the airways. AIM: This review presents the state-of-the-art in EBC-based omics approaches-particularly metabolomics and proteomics-to characterize molecular signatures associated with chronic respiratory (e.g. asthma, chronic obstructive pulmonary disease, and rhinitis) and infectious diseases (e.g. COVID-19). RESULTS: We critically examine findings from studies applying nuclear magnetic resonance (NMR), mass spectrometry (MS), and sensor-based technologies to analyze EBC across various respiratory conditions. NMR, valued for its reproducibility and minimal sample preparation, consistently discriminates among disease phenotypes, identifies distinct metabotypes, and monitors treatment response over time. MS-based approaches afford enhanced sensitivity and specificity, enabling detailed profiling of inflammatory mediators, such as lipid-derived eicosanoids and amino acid derivatives. Proteomic studies reveal protein-level alterations associated with inflammation and tissue remodeling. In COVID-19 and long COVID, metabolomic and volatile compound profiling distinguishes affected individuals from healthy controls suggesting clinical potential. However, inconsistent sample processing and lack of analytical standardization remain limiting factors. CONCLUSIONS: EBC profiling shows clear promise for improving diagnosis, monitoring, and stratification in respiratory medicine. Yet, translation into clinical practice is hindered by limited standardization and validation. Broader, longitudinal studies will be essential to establish robust molecular signatures across disease states. This review underscores the timely need to implement breathomics investigations to gain mechanistic insight into the underlying biology of respiratory diseases.

Humans↗

Molecular profiling of early stage liver fibrosis in patients with chronic hepatitis C virus infection.

The molecular mechanisms of acute hepatitis C virus (HCV) infection, end-stage hepatitis (cirrhosis), and hepatocellular carcinoma have been extensively studied, but little is known of the changes in liver gene expression during the early stages of liver fibrosis associated with chronic HCV infection, that is, the transition from normal liver (NL) of uninfected patients to the first stage of liver fibrosis (F1-CH-C). To obtain insight into the molecular pathogenesis of F1-CH-C, we used real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to study the mRNA expression of 240 selected genes in liver tissue with F1-CH-C, in comparison with NL. The expression of 54 (22.5%) of the 240 genes was significantly different between F1-CH-C and NL; 46 genes were upregulated and 8 were downregulated in F1-CH-C. The most noteworthy changes in gene expression mainly affected the transcriptional network regulated by interferons (IFNs), including both IFN-alpha/beta-inducible genes (STAT1, STAT2, ISGF3G/IRF9, IFI27, G1P3, G1P2, OAS2, MX1) and IFN-gamma-inducible genes (CXCL9, CXCL10, CXCL11). Interesting, upregulation of IFN-alpha/beta-inducible genes (but not IFN-gamma-inducible genes) was independent of histological scores (grade and stage of fibrosis) and HCV characteristics (hepatic HCV mRNA levels and the HCV genotype), and was specific to HCV (as compared to hepatitis B virus (HBV)). Other genes dysregulated in F1-CH-C, albeit less markedly than IFN-alpha/beta- and IFN-gamma-inducible genes, were mainly involved in the activation of lymphocytes infiltrating the liver (IFNG, TNF, CXCL6, IL6, CCL8, CXCR3, CXCR4, CCR2), cell proliferation (p16/CDKN2A, MKI67, p14/ARF), extracellular matrix remodeling (MMP9, ITGA2), lymphangiogenesis (XLKD1/LYVE), oxidative stress (CYP2E1), and cytoskeleton microtubule organization (STMN2/SCG10). Thus, a limited number of signaling pathways, and particularly the transcriptional network regulated by interferons, are dysregulated in the first stage of HCV-induced liver fibrosis. Some of the genes identified here could form the basis for new approaches aimed at refining IFN-based therapies for chronic HCV infection.

Gene Expression↗

Flow cytometry: a new approach for the molecular profiling of breast cancer.

The established method in prognosis of breast cancer includes detection of molecular markers, such as the estrogen receptor (ER), progesterone receptor (PR), and HER-2/neu. These markers are routinely checked via immunohistochemistry (IHC). HER-2/neu is also detected by fluorescent in situ hybridization (FISH). Flow cytometric analysis has not yet been used for detection of such markers. Flow cytometry was performed on four established breast cancer cell lines: MCF7, T47D, BT474, MDA-MB-231, and on one normal breast epithelial cell line: MCF10A. Flow cytometric analysis was used for the detection of ER, PR, HER-2/neu, epidermal growth factor receptor (EGFR), and E-cadherin. Currently, EGFR and E-cadherin are not standard predictive factors in determining survival of breast cancer patients, but both may be beneficial to prognosis. Cells undergoing flow cytometric analysis lost marker expression with increasing passage number. The highest expression was found at cells passaged 0-1 times. MCF7, T47D, and BT474 all had similar marker expression patterns. E-cadherin demonstrated a strongly positive pattern with marker expression of 85-92% among the three cell lines. ER, PR, and HER-2/neu demonstrated a weakly positive expression pattern when compared with E-cadherin. Marker expression ranged from 15 to 61%. These three cell lines were almost negative for expression of EGFR where expression ranged from 0 to 6%. MDA-MB-231 had almost no expression of all 5 markers, with positive values ranging from 0 to 5%. MCF10A had weak positive to almost negative expression values of ER, PR, HER-2/neu, and E-cadherin, which ranged from 3 to 13%. EGFR, both surface and cytoplasmic markers, again were not expressed in MCF10A cells with an expression value of <1%. We found that ER, PR, and HER-2/neu marker expressions in 5 out of 5 cell lines were consistent with established expression patterns. EGFR and E-cadherin expression in 4 out of 5 cell lines were also consistent with established expression patterns. We have shown that flow cytometry provides quantitative data on expression patterns of important prognostic markers in breast cancer.

Biomarkers, Tumor↗

Molecular profiles of the mouse postnatal development of the esophageal epithelium showing delayed growth start.

Studies on molecular mechanisms of self-renewal in normal stem cells are required for understanding the cancer stem cell. Self-renewal in many kinds of normal stem cells might be accelerated in the growth of a young organism and in the repair of damaged tissue. This study examined whether the esophagus in growing neonates provides an experimental system for studies on epithelial stem cell renewal. The esophageal epithelium consists of 3 layers, from the luminal side to the bottom: the differentiated, epibasal and basal cell layers. The basal cell layer is known to contain the stem cells for the esophageal epithelium. This basic architecture is observed both in mice and humans. We investigated the basal cells in the mouse neonate by immunostaining with a basal cell marker, nerve growth factor receptor (Ngfr), and compared the basal cell content in the esophageal epithelium between mice and humans. A mouse esophageal epithelial cell primary culture system was developed for studies on the basal cell growth and keratinocyte differentiation, and microarray analysis was conducted for obtaining expression profiles of the basal cells. It was revealed that the growth of the esophageal epithelium begins from postnatal day 3, and that the timing is consistent with membrane localization of Ngfr in the basal cell. An increase in the basal cell number by Ngf treatment is observed in in vitro mouse esophageal epithelium cultures. Furthermore, mRNA overexpression of Pdgfrb encoding platelet derived growth factor receptor beta and Egfr encoding epidermal growth factor receptor is associated with the timing of the growth of the esophageal epithelium in the neonatal mice. This study provides a new experimental model for studies on the growth of the basal cells, which are considered to include the stem cells, and on the enlargement of the body size in young organisms.

Animals↗

New facets of the neuropathology and molecular profile of human temporal lobe epilepsy.

This review summarizes the salient features of the anatomical and molecular neuropathology of the hippocampus from patients with intractable temporal lobe epilepsy (TLE). It argues that sclerotic hippocampus is essential for seizure expression and that sclerosis is not a consequence of seizures, but is related to the epileptogenicity of the seizure focus. While neurons in sclerotic hippocampus may contribute to hippocampal hyperexcitability, this role is perhaps less important than that of the astrocytes. The astrocytes in sclerotic hippocampus may directly influence excitability through altered water homeostasis and K+ buffering by redistribution of AQP4 transporters on their plasma membrane. It is proposed that they contribute to a high extracellular glutamate level through reduced glutamine synthetase, and activation through pro-inflammatory factors that release chemokines and cytokines, which enhance calcium-dependent glutamate release. Such a focal pool of glutamate may diffuse to surrounding neuron-rich areas to generate seizure activity in TLE.

Animals↗

Molecular profiling of signalling proteins for effects induced by the anti-cancer compound GSAO with 400 antibodies.

BACKGROUND: GSAO (4-[N-[S-glutathionylacetyl]amino] phenylarsenoxide) is a hydrophilic derivative of the protein tyrosine phosphatase inhibitor phenylarsine oxide (PAO). It inhibits angiogenesis and tumour growth in mouse models and may be evaluated in a phase I clinical trial in the near future. Initial experiments have implicated GSAO in perturbing mitochondrial function. Other molecular effects of GSAO in human cells, for example on the phosphorylation of proteins, are still largely unknown. METHODS: Peripheral white blood cells (PWBC) from healthy volunteers were isolated and used to profile effects of GSAO vs. a control compound, GSCA. Changes in site-specific phosphorylations, other protein modifications and expression levels of many signalling proteins were analysed using more than 400 different antibodies in Western blots. RESULTS: PWBC were initially cultured in low serum conditions, with the aim to reduce basal protein phosphorylation and to increase detection sensitivity. Under these conditions pleiotropic intracellular signalling protein changes were induced by GSAO. Subsequently, PWBC were cultured in 100% donor serum to reflect more closely in vivo conditions. This eliminated detectable GSAO effects on most, but not all signalling proteins analysed. Activation of the MAP kinase Erk2 was still observed and the paxillin homologue Hic-5 still displayed a major shift in protein mobility upon GSAO-treatment. A GSAO induced change in Hic-5 mobility was also found in endothelial cells, which are thought to be the primary target of GSAO in vivo. CONCLUSION: Serum conditions greatly influence the molecular activity profile of GSAO in vitro. Low serum culture, which is typically used in experiments analysing protein phosphorylation, is not suitable to study GSAO activity in cells. The signalling proteins affected by GSAO under high serum conditions are candidate surrogate markers for GSAO bioactivity in vivo and can be analysed in future clinical trials. GSAO effects on Hic-5 in endothelial cells may point to a new intracellular GSAO target.

Adult↗

Molecular profile of human immunodeficiency virus type 1 infection in symptomless patients and in patients with AIDS.

Recent molecular evidence indicates that active human immunodeficiency virus type 1 (HIV-1) infection is detectable in both symptomless and symptomatic infected patients. For this main reason, it has been pointed out that precise quantitative analysis of viral activity in vivo is necessary, firstly, for the pathogenetic investigation of the steps relevant to infection progression and, secondly, for better clinical management of HIV-1-infected patients. In this study, the presence of HIV-1 genomic RNA in plasma samples, specific HIV-1 transcripts in peripheral blood mononuclear cells, and proviral DNA sequences were assayed for 33 HIV-1-infected patients (including symptomless and symptomatic subjects) by using a competitive polymerase chain reaction method that allows quantitation of the RNA/DNA target sequences. The quantitative results obtained confirm that transcription of HIV-1 structural genes and complete viral replication occur in all the HIV-1-infected patients independently of the clinical stage. However, although sharp individual differences were detected, a high degree of correlation of the molecular parameters studied with both disease progression and a decrease in the number of CD4+ T lymphocytes was documented. Interestingly, despite the increasing viremia level associated with infection progression, the mean transcriptional activity of individual infected cells was found to be only moderately greater in AIDS patients than in asymptomatic infected subjects. In addition, it was noted that quantitation of HIV-1 genomic RNA in plasma samples and quantitation of specific HIV-1 transcripts in peripheral blood mononuclear cells appear to be more reliable and sensitive markers of viral activity than quantitative analysis of proviral HIV-1 sequences in peripheral lymphocytes.

Acquired Immunodeficiency Syndrome↗

Molecular profiling of human hepatocellular carcinoma defines mutually exclusive interferon regulation and insulin-like growth factor II overexpression.

Molecular subtyping of human hepatocellular carcinoma (HCC) with potential mechanistic and therapeutic impact has not been achieved thus far. We have analyzed the mRNA expression patterns of 43 different human HCC samples and 3 HCC cell lines in comparison with normal adult liver using high-density cDNA microarrays. Two main groups of HCC, designated group A (65%) and group B (35%), were distinguished based on clustering of the most highly varying genes. Group A HCCs were characterized by induction of a number of interferon (IFN)-regulated genes, whereas group B was characterized mainly by down-regulation of several apoptosis-relevant and IFN-regulated genes. The number of apoptotic tumor cells and tumor-infiltrating lymphocytes was significantly higher in tumors of group A as compared with those of group B. Based on the expression pattern, group B was further subdivided into two subgroups, designated subgroup B1 (6 of 43 tumors, 14%) and subgroup B2 (9 of 43 tumors, 21%). A prominent characteristic of subgroup B1 was high overexpression of insulin-like growth factor (IGF)-II. All tested HCC cell lines expressed equally high concentrations of IGF-II transcripts and co-segregated with group B1 in clustering. IGF-II overexpression and induction of IFN-related genes were mutually exclusive, even when analysis was extended to other cancer expression profile studies. Moreover, IFN-gamma treatment substantially reduced IGF-II expression in HCC cells. In conclusion, cDNA microarray analyses provided subtyping of HCCs that is related to intratumor inflammation and tumor cell apoptosis. This profiling may be of mechanistic and therapeutic impact because IGF-II overexpression has been linked to reduced apoptosis and increased proliferation and may be accessible to therapeutic intervention.

Carcinoma, Hepatocellular↗

DNA microarray allows molecular profiling of rheumatoid arthritis and identification of pathophysiological targets.

This study was undertaken to evaluate the possibility to obtain a molecular signature of rheumatoid arthritis (RA) comparatively osteoarthritis (OA), and to lay the bases to develop new diagnostic tools and identify new targets. Microarray technology was used for such an analysis. The gene expression profiles of synovial tissues from patients with confirmed RA, and patients with OA were established and compared. A set of 63 genes was selected, based, more specifically, on their overexpression or underexpression in RA samples compared to OA. Results for six of these genes have been verified by quantitative PCR using both samples identical to those used in the microarray experiments and entirely separate samples. Expression profile of the 48 known genes allowed the correct classification of additional RA and OA patients. Furthermore, the distinct expression of three of the selected genes was also studied by quantitative RT-PCR in cultured synovial cells. Detailed analysis of the expression profile of the selected genes provided evidence for dysregulated biological pathways, pointed out to chromosomal location and revealed novel genes potentially involved in RA. It is proposed that such an approach allows valuable diagnosis/prognostics tools in RA to be established and potential targets for combating the disease to be identified.

Adult↗

Molecular profiling of antipsychotic drug function: convergent mechanisms in the pathology and treatment of psychiatric disorders.

Despite great progress in antipsychotic drug research, the molecular mechanisms by which these drugs work have remained elusive. High-throughput gene profiling methods have advanced this field by allowing the simultaneous investigation of hundreds to thousands of genes. However, different methodologies, choice of brain region, and drugs studied have made comparisons across different studies difficult. Because of the complexity of gene expression changes caused by drugs, teasing out the most relevant expression differences is a challenging task. One approach is to focus on gene expression changes that converge on the same systems that were previously deemed important to the pathology of psychiatric disorders. From the microarray studies performed on human postmortem brain samples from schizophrenics, the systems most implicated to be dysfunctional are synaptic machinery, oligodendrocyte/myelin function, and mitochondrial/ubiquitin metabolism. Drugs may act directly or indirectly to compensate for underlying pathological deficits in schizophrenia or via other mechanisms that converge on these pathways. Side effects, consisting of motor and metabolic dysfunction (which occur with typical and atypical drugs, respectively), also may be mediated by gene expression changes that have been reported in these studies. This article surveys both the convergent antipsychotic mechanisms and the genes that may be responsible for other effects elicited by antipsychotic drugs.

Animals↗

Tissue microarrays for miniaturized high-throughput molecular profiling of tumors.

New high-throughput screening technologies such as complementary (cDNA) microarrays allow identification of hundreds of candidate genes in one experiment. To prioritize the leads obtained in such studies, it is necessary to analyze a large number of tissues for candidate gene expression. Tissue microarray (TMA) technology greatly facilitates such analyses. In this method, hundreds of minute tissue samples (0.6-mm diameter) can be placed on one microscope glass slide. The TMA approach allows simultaneous analysis of all tissues with in situ methods (immunohistochemistry, fluorescence in situ hybridization, RNA in situ hybridization) of all tumors in one experiment under highly standardized conditions. TMAs are not restricted to solid tumors but can be manufactured from a variety of other sources, including cell lines, xenografts, and hematologic tissues. In addition to tumor type-specific applications that comprise large numbers of one particular tumor type with extensive histopathologic and clinical data, TMAs are well suited for large-scale molecular epidemiologic studies. For example, genes of interest can be analyzed in multitissue TMAs containing a variety of different human normal tissues and tumor entities. Once tumor types are identified, where a given molecular alteration plays a role, the clinical significance of this molecular alteration can be investigated on tumor-specific TMAs. Thus, TMA technology allows miniaturized high-throughput molecular epidemiologic studies. The TMA technique will markedly accelerate the transition from basic research to clinical applications.

Gene Expression Profiling↗

Molecular profiling of anemia in acute renal allograft rejection using DNA microarrays.

Compromised renal function after renal allograft transplantation often results in anemia in the recipient. Molecular mechanisms leading to anemia during acute rejection are not fully understood; inadequate erythropoietin production and iron deficiency have been reported to be the main contributors. To increase our understanding of the molecular events underlying anemia in acute rejection, we analyzed the gene expression profiles of peripheral blood lymphocytes (PBL) from four pediatric renal allograft recipients with acute rejection and concurrent anemia, using DNA microarrays containing 9000 human cDNA clones (representing 7469 unique genes). In these anemic rejecting patients, an 'erythropoiesis cluster' of 11 down-regulated genes was identified, involved in hemoglobin transcription and synthesis, iron and folate binding and transport. Additionally, some alloimmune response genes were simultaneously down-regulated. An independent data set of 36 PBL samples, some with acute rejection and some with concurrence of acute rejection and anemia, were analyzed to support a possible association between acute rejection and anemia. In conclusion, analysis using DNA microarrays has identified a cluster of genes related to hemoglobin synthesis and/or erythropoeisis that was altered in kidneys with renal allograft rejection compared with normal kidneys. The possible relationship between alterations in the expression of this cluster, reduced renal function, the alloimmune process itself, and other influences on the renal transplant awaits further analysis.

5-Aminolevulinate Synthetase↗

Molecular profiling of bladder tumors based on the detection of FGFR3 and TP53 mutations.

PURPOSE: On a routine basis we performed systematic molecular screening for FGFR3 and TP53 mutations in 121 bladder tumors. We then specifically analyzed the predictive value of the recurrence of FGFR3 and TP53 genotypes in superficial lesions. MATERIALS AND METHODS: The FGFR3 gene was analyzed by direct sequencing of exons 7, 10 and 15, whereas TP53 status was determined using the p53 functional assay in yeast. RESULTS: We identified a missense FGFR3 mutation in 66% of pTa, 26% of pT1 and 12% of pT2 tumors. Of activating FGFR3 mutations 54% and 85% were found in low G1 and intermediate G2 grade tumors, respectively, but in only 20% of high grade G3 tumors. We detected inactivating TP53 mutations in 10% of pTa, 42% of pT1 and 58% of pT2 tumors. Moreover, TP53 mutations were found only in 23% of grade G1 and 3% of grade G2 tumors but in 44% of high grade G3 tumors. When the 2 genotypes were combined, we observed that 58% of pTa tumors had the (mutant FGFR3, WT TP53) genotype, whereas 58% of invasive lesions harbored the inverse genotype (WT FGFR3, mutant TP53). The (mutant FGFR3, WT TP53) genotype and the (WT FGFR3, mutant TP53) genotype were detected in 23% and 38% of pT1G3 tumors, respectively. In the subgroup of 92 patients with superficial pTa-T1 bladder tumors we did not find that the TP53 or FGFR3 genotype alone or combined had a predictive value for tumor recurrence. CONCLUSIONS: Our data again represent solid proof for the pivotal role of FGFR3 and TP53 mutations in superficial and invasive bladder tumors, respectively. However, other molecular markers should be identified for borderline pT1G3 bladder tumors, which are probably at the crossroads of these 2 distinct molecular pathways.

Aged↗

Molecular profiling of genes up-regulated during promotion by phenobarbital treatment in a medium-term rat liver bioassay.

In search of genes that are steadily up-regulated during the promotion stage in carcinogenesis, suppression PCR subtractive hybridization and following northern blot screening were performed using a phenobarbital (PB)-promotion model based on a medium-term liver bioassay. Two weeks after a single injection of diethylnitrosamine (DEN; 200 mg/kg body wt, i.p.), rats were given 600 p.p.m. PB in the drinking water for up to 64 weeks. For comparison, animals fed 1 p.p.m. ethinylestradiol (EE) or 3000 p.p.m. butylated hydroxytoluene (BHT) in the diet at promotion stage were also included. Rats were subjected to partial hepatectomy (PH) at week 3. In addition, dose-dependence of PB at week 8 of promotion and responsiveness to representative non-genotoxic carcinogens without DEN initiation were examined. Fragments of a total of 67 different genes were isolated from the up-regulated gene population in the liver at day 10 of PB treatment by subtracting from basal expression of DEN + PH alone. Using northern blot screening for signal-detectable 48 genes, 16 genes showed up-regulation in the livers at week 8 of promotion, common to the PB and EE treatments with the levels being three times or more than the basal expression of unpromoted liver. The majority of these genes were also up-regulated at week 8 by BHT treatment, and were also constitutively expressed in the DEN(-), PH(-) untreated rat livers. Among the up-regulated genes common to the PB and EE promotion, and not responding to the non-genotoxic carcinogens in uninitiated liver, the following six genes showed overexpression in PB-promoted hepatocellular carcinomas at week 64, with the levels three times or more than untreated rat liver: ubiquitously expressed mammalian ABC half transporter, apolipoprotein A4, nuclear receptor binding factor-2, CD81, hypothetical protein (HSPC014) and one unidentified gene. These genes might be candidates for biomarkers in screening of non-genotoxic hepatocarcinogens by analysis in two-stage carcinogenesis models.

Animals↗

Molecular profiling and weight determination of heparins and depolymerized heparins.

The recently proposed calibrant LHN-1 (lot F537; henceforth designated F537), for the molecular weight (MW) determination by high-performance size-exclusion chromatography of heparins, is shown here to have a range too narrow to allow for the accurate MW determination of all low molecular weight heparins (LMWHs). We have recently demonstrated, by this same methodology, that a chemically degraded benzyl ester of unfractionated heparin, heparin mass calibrator (HMC), is a better calibrant. Weight-average MW, number-average MW, peak MW, and dispersity values were calculated with F537, HMC, and by a reference narrow-range-calibration method for various LMWHs and unfractionated heparins. Values for these parameters determined with HMC were not significantly different from those determined by the reference method until the MW of the substance exceeded 15.0 kDa. In contrast, the MW profile obtained with F537 was appreciably different from that obtained by the reference method for samples with MWs > 7.5 kDa. The range exhibited by HMC should allow this calibrant to be used for both LMWHs and unfractionated heparins.

Heparin↗

Molecular profiling of laser-microdissected matched tumor and normal breast tissue identifies karyopherin alpha2 as a potential novel prognostic marker in breast cancer.

PURPOSE: The aim of the present study was to identify human genes that might prove useful in the diagnosis and therapy of primary breast cancer. EXPERIMENTAL DESIGN: Twenty-four matched pairs of invasive ductal breast cancer and corresponding benign breast tissue were investigated by a combination of laser microdissection and gene expression profiling. Differential expression of candidate genes was validated by dot blot analysis of cDNA in 50 pairs of matching benign and malignant breast tissue. Cellular expression of candidate genes was further validated by RNA in situ hybridization, quantitative reverse transcription-PCR, and immunohistochemistry using tissue microarray analysis of 272 nonselected breast cancers. Multivariate analysis of factors on overall survival and recurrence-free survival was done. RESULTS: Fifty-four genes were found to be up-regulated and 78 genes were found to be down-regulated. Dot blot analysis reduced the number of up-regulated genes to 15 candidate genes that showed at least a 2-fold overexpression in >15 of 50 (30%) tumor/normal pairs. We selected phosphatidic acid phosphatase type 2 domain containing 1A (PPAPDC1A) and karyopherin alpha2 (KPNA2) for further validation. PPAPDC1A and KPNA2 RNA was up-regulated (fold change >2) in 84% and 32% of analyzed tumor/normal pairs, respectively. Nuclear protein expression of KPNA2 was significantly associated with shorter overall survival and recurrence-free survival. Testing various multivariate Cox regression models, KPNA2 expression remained a highly significant, independent and adverse risk factor for overall survival. CONCLUSIONS: Gene expression profiling of laser-microdissected breast cancer tissue revealed novel genes that may represent potential molecular targets for breast cancer therapy and prediction of outcome.

Biomarkers, Tumor↗

Giant cell tumors of the bone: molecular profiling and expression analysis of Ephrin A1 receptor, Claudin 7, CD52, FGFR3 and AMFR.

Giant cell tumors (GCTs) of the bone are osteolytic neoplasms with variable degrees of aggressiveness. The aim of this study was the molecular characterization of GCT tissue. We established gene expression profiles and discovered a number of genes that have not been described in GCTs before. RNA was prepared from 7 cryopreserved GCTs (primary tumors n = 5, relapses n = 2) and was hybridized to Affymetrix HG U133A microarrays. Paraffin-embedded samples were used for immunohistochemical validation (primary tumors n = 16, relapses n = 6). Gene ontology revealed that the majority of genes, found to be differentially expressed between primary and recurrent GCTs, were associated with receptor tyrosine kinase activity. We selected one upregulated gene (Claudin 7) and four downregulated genes (CD52, Ephrin A1 receptor, autocrine motility factor receptor [AMFR] and fibroblast growth factor receptor 3 [FGFR3] for further analysis using immunohistochemistry. Immunohistochemical analysis of CD52, AMFR, and Ephrin A1 receptor revealed expression profiles concordant with the microarray data, also with regard to differences between primary tumors and relapses.

Adult↗

Expression microdissection: operator-independent retrieval of cells for molecular profiling.

Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting. Expression microdissection (xMD) offers significant advantages over available methods, including an increase in dissection speed of several orders of magnitude. xMD may become a valuable tool for investigators studying cancer or other disease states in patient specimens and animal models.

Animals↗