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PubMed2004

Chimerism of metanephric adenoma but not of carcinoma in kidney transplants.

Recipient-derived cells integrate into renal allografts inducing organ-specific microchimerism. Circulating pluripotent progenitor cells with high plasticity for differentiation were suggested as a potential source of allograft chimerism. Whether or not these cells also contribute to tumor formation in renal transplants is unknown. We analyzed six histologically different tumors in renal allografts for the presence of recipient-derived cells. To circumvent dependency on gender mismatch, a polymerase chain reaction assay for highly polymorphic short tandem repeat marker (DNA fingerprinting) in combination with laser microdissection was applied. Pure tumor cell populations were harvested by laser microdissection after immunohistochemical (CD45/CD68) marking of contaminating leukocytes. In cases of gender mismatch (n = 2), results were confirmed by sex chromosome in situ hybridization. Two metanephric adenomas demonstrated microchimerism comprising both donor- and recipient-derived tumor cells. Two clear cell carcinomas, one transitional cell carcinoma, and one renal cortical adenoma were all of donor origin without chimerism. We conclude that except for metanephric adenomas, tumors arising in renal transplants originate completely from graft cells. The mixed derivation of metanephric adenomas indicates an incorporation of recipient-derived progenitor cells. This finding suggests that adult stem cells can assume neoplastic phenotypes.

Adenocarcinoma, Clear Cell↗

PubMed2004

Vascular endothelial growth factor-A is expressed both on lymphoma cells and endothelial cells in angioimmunoblastic T-cell lymphoma and related to lymphoma progression.

Vascular endothelial growth factor-A (VEGF-A), a main stimulator of endothelial cell proliferation, plays an important role on tumor angiogenesis. Angioimmunoblastic T-cell lymphoma (AITL) show the most prominent vascular component among lymphomas and their prognosis is difficult to predict. To assess the clinical significance of VEGF-A in AITL, VEGF-A gene expression was studied in the tumoral lymph nodes of 24 patients using laser microdissection and quantitative polymerase chain reaction. VEGF-A gene was overexpressed in both microdissected lymphoma and endothelial cells. Increased levels of VEGF-A gene expression in lymphoma cells, as in endothelial cells, were related to extranodal involvement and to short survival time. Accordingly, VEGF-A protein expression was also found in both types of cells in lymph nodes and bone marrows with lymphomatous involvement. Triple immunofluorescent labeling on lymph node sections showed that VEGF-A protein and its receptor VEGF-R1 were coexpressed on endothelial cells of microvessels in the areas of lymphoma invasion. In these areas, ultrastructural study showed dystrophic microvessels. Taken together, the value of VEGF-A gene expression as an adverse prognostic marker in AITL should thus be considered. In addition to lymphoma cells themselves, the vascular component, a critical pathologic characteristic in AITL, also contributes to lymphoma progression.

Adult↗

PubMed2007

Evaluation of Phi29-based whole-genome amplification for microarray-based comparative genomic hybridisation.

For the optimal performance of high throughput genomic technologies sufficient yields of high-quality DNA are crucial. Following microdissection, most samples fail to produce sufficient quantities of DNA for genome-wide experiments. Various PCR-based amplification methods have been used, but these usually produce nonuniform representations of the genome. Bacteriophage Phi29 DNA polymerase random-primed DNA amplification is based on isothermal multiple displacement amplification. We sought to define the genome representation of this method in a bacterial artificial chromosome microarray comparative genomic hybridisation (aCGH) platform. Test genomic female DNA was amplified using Phi29 amplification at four different starting concentrations (0.5, 5, 10 and 50 ng). These products were combined with unamplified and amplified genomic female DNA as reference. In addition, 50 ng of DNA from five microdissected breast cancer frozen samples, were amplified using the same method. Three combinations were performed: unamplified test with unamplified reference, amplified test with unamplified reference and both amplified tumour and reference DNA. aCGH was performed with an in-house 16 K BAC platform (a resolution of approximately 100 Kb). Pearson's correlation tests and hierarchical clustering were performed to compare the profiles obtained. aCGH profiles obtained with amplified test and unamplified reference female genomic DNA showed copy number biases throughout the genome. These biases were more conspicuous with smaller amounts of starting material and mapped to regions of known copy number polymorphisms. When similar concentrations of test and reference DNA were amplified, the biases were significantly reduced, rendering accurate profiles. For the tumours, representative profiles were obtained when both test and reference DNA were amplified. Phi29 amplification induces copy number biases and unamplified material remains the gold standard for copy number analysis. For accurate results using Phi29 amplification, samples subjected to aCGH analysis should be combined with reference DNA amplified with the same method, using similar amounts of starting template.

Breast Neoplasms↗

PubMed2006

Determination of sequential mutation accumulation in pancreas and bile duct brushing cytology.

Neoplastic progression is characterized by clonal expansion of tumor cells associated with accumulation of mutational damage. The timing of mutation acquisition could be of value in distinguishing preneoplastic conditions from early and advanced cancer as well as characterizing tumor aggressiveness and treatment response. Using quantitative methods applied to microdissected cell clusters selected according to cytomorphologic features, we sought to demonstrate the feasibility and efficacy for determining the time and course of mutation accumulation in pancreatobiliary cytology specimens. In all, 40 pancreatic duct and 21 biliary brushing cytology specimens were retrieved from the cytology database. Xylene-resistant markings were placed on the slide underside and coverslips removed. Clusters of benign, atypical and malignant cells were manually microdissected and DNA extracted. Mutations (allelic imbalance) (loss of heterozygosity) were quantitatively determined for a broad panel of 15 markers (1p, 3p, 5q, 9p, 10q, 17p, 17q, 21q, 22q) as well as point mutation in K-ras-2 using PCR/capillary electrophoresis. Time course was based on earlier mutations having a higher proportion of mutant DNA for a particular marker. The descending frequency of detectable mutational involvement in pancreatic cytology was K-ras-2 point mutation (58%), 3p25-26 and 17q21 (35%), 5q23 (33%), 1p36 (28%), followed by the remaining molecular markers. The descending frequency of mutational content in bile duct cytology was 17p13, 1p36, 3p25-26, and 5q23 followed by remaining molecular markers. K-ras-2 point mutation was not seen in bile duct specimens. While there was overlap in the spectrum of mutational markers in pancreatic duct and biliary brushing cytology, the temporal profile was significantly different (P<0.001). Pancreatic and biliary neoplasia progression involves distinct subset of accumulated defined mutations. Determination of timing of the mutational damage in cytologic material could be incorporated in the work-up and help in making a more definitive diagnosis of malignancy in pancreatobiliary cytology specimens.

Biliary Tract Neoplasms↗

PubMed2026

DeepPlaque: a scalable multimodal platform for Aβ pathology and cell analysis in Alzheimer's disease.

Histological analysis is essential for understanding disease pathology and the microenvironment, particularly in Alzheimer's disease (AD), characterized by beta-amyloid (Aβ) plaques that exist as diffuse, fibrillar, and core species, with distinct toxicity levels. However, accurate classification of Aβ plaque types in postmortem brain tissues and profiling of surrounding cells present significant challenges. To address these challenges, we developed "DeepPlaque", an integrated system featuring "PlaqueNet", a deep learning model for automated classification of Aβ plaque species from diverse imaging platforms. DeepPlaque includes automated workflows for cellular phenotyping and proteomic profiling through targeted laser microdissection. PlaqueNet achieves expert-level accuracy (AUC > 90%) in classifying the 3 major Aβ plaque species, supporting consistent and large-scale annotation. By integrating spatial cellular phenotyping with laser microdissection, DeepPlaque enables high-throughput proteomic analysis of Aβ plaque niches, revealing that microglia are more abundant around core and fibrillar Aβ plaques, with increased expression of apolipoprotein E and amyloid precursor protein in core Aβ plaques. This customizable platform enhances the molecular and cellular characterization of Aβ plaque-associated environments, providing critical insights into AD pathology.

Alzheimer Disease↗

PubMed2006

Heterogeneity of T-cell clones infiltrating primary malignant melanomas.

It is established that primary malignant melanomas (pMM) can be infiltrated by T-cell populations with predominantly one T-cell clone. As pMM generally express multiple tumor-associated antigens (TAA), here we used laser-capture microdissection (LCM) to isolate different tumor-infiltrating lymphocyte (TIL) clusters in order to determine whether pMM are infiltrated only by one single clone or whether the TAA may attract various T-cell populations. As T-cell receptor (TCR) clonality is a useful tool for the demonstration of specific T-cell clones, we analyzed 56 pMM, three cutaneous melanoma metastases, and 15 pairs of pMM with a sentinel lymph node (SLN) for clonal rearrangements of the (TCR) gamma chain gene. We detected the clonality of TCR gamma chain gene in 25 of 56 pMM, and in 10 of 17 SLN studied. In four of the 15 pairs of primary tumor and SLN, we found clonal TCR gamma in both the melanoma and the SLN, with two pairs harboring the identical clone. As we detected different clones in pMM and the corresponding SLN, we subsequently performed LCM in 21 malignant melanomas with multiple lymphocytic clusters for the presence of focal clonal T cells in different regions of the melanoma. In seven melanomas, both clusters of TILs showed the same rearranged TCR gamma chain gene and in five of the seven biopsies the clonal rearrangement occurred in different variable (V) regions of the TCR gamma chain gene. These tumors showed infiltration by more than one clone. In 10 biopsies TCR clonality was restricted to one cluster, while the second microdissected sample of the infiltrate was polyclonal. In conclusion, within one primary malignant melanoma several T-cell clones with different rearrangements may occur. The balance between these clones may decide on the progress of melanoma.

Clone Cells↗

PubMed2006

Mitochondrial neurogastrointestinal encephalomyopathy: evidence of mitochondrial DNA depletion in the small intestine.

BACKGROUND & AIMS: Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease clinically defined by gastrointestinal dysmotility, cachexia, ptosis, ophthalmoparesis, peripheral neuropathy, white-matter changes in brain magnetic resonance imaging, and mitochondrial abnormalities. Loss-of-function mutations in thymidine phosphorylase gene induce pathologic accumulations of thymidine and deoxyuridine that in turn cause mitochondrial DNA (mtDNA) defects (depletion, multiple deletions, and point mutations). Our study is aimed to define the molecular basis of gastrointestinal dysmotility in a case of MNGIE. METHODS: By using laser capture microdissection techniques, we correlated histologic features with mtDNA abnormalities in different tissue components of the gastrointestinal wall in a MNGIE patient and ten controls. RESULTS: The patient's small intestine showed marked atrophy and mitochondrial proliferation of the external layer of muscularis propria. Genetic analysis revealed selective depletion of mtDNA in the small intestine compared with esophagus, stomach, and colon, and microdissection analysis revealed that mtDNA depletion was confined to the external layer of muscularis propria. Multiple deletions were detected in the upper esophagus and skeletal muscle. Site-specific somatic point mutations were detected only at low abundance both in the muscle and nervous tissue of the gastrointestinal tract. Analysis of the gastrointestinal tract from 10 controls revealed a non-homogeneous distribution of mtDNA content; the small intestine had the lowest levels of mtDNA. CONCLUSION: Atrophy, mitochondrial proliferation, and mtDNA depletion in the external layer of muscularis propria of small intestine indicate that visceral myopathy is responsible for gastrointestinal dysmotility in this MNGIE patient.

Adult↗

PubMed2005

Accurate genotyping from paraffin-embedded normal tissue adjacent to breast cancer.

Genetic polymorphism analysis for disease risk is widely used in epidemiology studies; blood or oral cavity cells are the most widely used source of DNA. However, these types of samples are not always available, particularly for studies that were conducted years ago. An alternative potential source of patient DNA exists in the form of paraffin-embedded normal tissue adjacent to tumor samples, which are collected and stored routinely for clinical use. The use of such samples can be conceptually problematic, however, due to the presence of field cancerization in the surrounding normal tissue, with the possible presence of chromosomal loss. Specifically, loss of heterozygosity (LOH) might bias the genotyping results and cause genotype misclassification. However, field cancerization and LOH might not be an issue because LOH is not easily found unless there is careful microdissection of only tumor cells (leaving stromal, inflammatory and fat cells), for example, laser-capture microdissection. In this study, we set out to determine the degree of genotype misclassification from normal tissues adjacent to tumors, if any, by comparing these results with blood genotyping. We examined samples from 106 subjects with breast cancer, analyzing five different genotypes selected from regions commonly known to have LOH in breast cancer. These genotypes were methylenetetrahydrofolate reductase (MTHFR), oxoguanosine glycosylase 1 (hOGG1), dopamine beta-hydroxylase (DBH), dopamine receptor D2 (DRD2) and NAD(P)H dehydrogenase quinone 1 (NQO1), conducted by using real-time PCR and TaqMan genotyping analyses. We found that among these five genotypes and 106 comparisons, there was a 100% concordance for genotyping from normal tissue adjacent to tumor and from blood. Our findings indicate that the use of adjacent normal tissues provides accurate genotyping results with high specificity. Although this study only used breast tumor samples, and may be applicable only to breast cancer studies, we expect the results to be applicable to other types of cancers also.

Biopsy↗

PubMed2006

Gene promoter methylation in prostate tumor-associated stromal cells.

BACKGROUND: Gene expression can be silenced through the methylation of specific sites in the promoter region. This mechanism of gene silencing has an important role in the carcinogenesis of prostate and other cancers. Although tumor-associated stromal cells also exhibit changes in gene expression, promoter methylation has not been described in these cells. METHODS: Tumor epithelia, tumor-associated stroma and normal epithelia, and stroma adjacent to tumor tissues were isolated from whole-mount prostatectomy specimens (two per patient) of patients (n = 5) with localized prostate cancer and from normal epithelia and stroma from benign prostate hyperplasia specimens (two per patient) from men (n = 5) without prostate cancer by using laser capture microdissection or expression microdissection. The methylation status of three genes important in prostate carcinogenesis, GSTP1, RARbeta2, and CD44, were evaluated using quantitative methylation-sensitive polymerase chain reaction. RESULTS: GSTP1 and RARbeta2 were methylated in the tumor epithelium of all five prostate cancer patients and in the tumor-associated stroma in four of the five patients. CD44 was methylated in the tumor epithelium from four of the five patients but not in the tumor stroma. GSTP1 and RARbeta2 were methylated in normal epithelium of two and four patients, respectively, and in normal stroma of one and two patients, respectively, that were isolated from regions adjacent to the tumors and may have resulted from a tumor-field effect; CD44 methylation was not observed in normal epithelium or stroma. In contrast, normal epithelia and stroma from benign prostate hyperplasia specimens showed no promoter methylation in GSTP1, RARbeta2, or CD44. CONCLUSIONS: The observation of promoter methylation in the non-neoplastic cells of the prostate tumor microenvironment may advance our understanding of prostate cancer development and progression and lead to new diagnostic and prognostic markers and therapeutic targets.

Aged↗

PubMed2005

Embryonic stem cells in predictive cardiotoxicity: laser capture microscopy enables assay development.

Embryonic stem (ES) cells offer unprecedented opportunities for in vitro drug discovery and safety assessment of compounds. Cardiomyocytes derived from ES cells enable development of predictive cardiotoxicity models to increase the safety of novel drugs. Heterogeneity of differentiated ES cells limits the development of reliable in vitro models for compound screening. We report an innovative and robust approach to isolate ES-derived cardiomyocytes using laser microdissection and pressure catapulting (LMPC). LMPC cells were readily applied onto 96-well format in vitro pharmacology assays. The expression of developmental and functional cardiac markers, Nkx 2.5, MLC2V, GATA-4, Connexin 43, Connexin 45, Serca-2a, cardiac alpha actin, and phospholamban, among others, was confirmed in LMPC ES-derived cardiomyocytes. Functional assays exhibited cardiac-like response to increased extracellular calcium (5.4 mM extracellular Ca2+) and L-type calcium channel antagonist (1 microM nifedipine). In conclusion, laser microdissection and pressure catapulting is a robust technology to isolate homogeneous ES-derived cell types from heterogeneous populations applicable to assay development.

Animals↗

PubMed2005

Postnatal expression of aquaporins in epithelial cells of the rat epididymis.

The mammalian aquaporins (AQPs) are a family of 13 transmembrane channel proteins that are involved in the transport of water in numerous organs. In the male excurrent duct, the movement of fluid and solutes across the epithelium is essential for establishing the proper luminal environment in which sperm mature and are stored. AQP9 is abundantly expressed in the efferent ducts, the epididymis, and the vas deferens, where it could represent an important apical pathway for transmembrane water and solute movement. However, other organs in which water transport is critical, including the kidney, the lung, or the eye, express several different AQPs with a cell-specific pattern. To undertake a systematic analysis of the expression of known AQPs in the postnatal and adult rat epididymis, we examined the expression of their respective mRNAs in epithelial cells isolated by laser capture microdissection (LCM), and we determined their corresponding protein expression pattern by immunofluorescence and Western blotting. Our data show that, whereas AQP9 is the main AQP of the epididymis, the mRNA specific for Aqp2, 5, 7, and 11 are also expressed in epididymal epithelial cells. AQP5 protein colocalizes with AQP9 in the apical membrane of a subpopulation of principal cells in the corpus and cauda regions. Aqp2 mRNA was detected in epithelial cells after the second postnatal week and the amount significantly increased up to adulthood. However, AQP2 protein was detected only in the distal cauda of young rats (between the second and fourth postnatal week). No AQP2 protein was detected in the adult epididymis, indicating that posttranscriptional mechanisms are involved in the regulation of AQP2 expression. In addition, epididymal epithelial cells express significant amounts of the mRNAs coding for AQP7 and 11. No mRNA or protein for AQPs 0, 4, 6, and 8 were detectable in epithelial cells, and Aqp1 was detected in whole epididymal samples, but not in epithelial cells. Thanks to the recent development of microdissection technologies, our observations suggest that epididymal epithelial cells express several members of the AQP family with a region-specific pattern. AQPs may be involved not only in the transepithelial transport of water in the epididymis but also in the postnatal development of this organ, as suggested by the differential expression of AQP2.

Age Factors↗

PubMed2003

BRAF mutation: a frequent event in benign, atypical, and malignant melanocytic lesions of the skin.

BRAF mutations have recently been detected with a high frequency (66%) in cutaneous melanoma. All those mutations are activating, with a single substitution (T1796A) at codon 599 (V599E) accounting for over 90%. To investigate the stage in which those mutations occur in the currently proposed sequential malignant transformation of melanocytes, 22 benign melanocytic nevi, 23 melanocytic atypical nevi, and 25 primary cutaneous melanoma from 63 different patients were examined for BRAF mutations using DNA extracted from microdissected formalin-fixed and paraffin-embedded tissues, and a two-round PCR-RFLP-based strategy. A subset of samples was sequenced for mutation confirmation. Sixteen benign (73%) and eleven atypical (52%) melanocytic nevi, and thirteen melanoma (56%) demonstrated BRAF mutations at codon 599, and no statistically significant differences were detected among all three types of lesions. No mutations were demonstrated in microdissected epidermal keratinocytes adjacent to melanocytic lesions having BRAF mutations. No correlation was detected between BRAF mutational status and age, sun exposure, and Clark's level in malignant melanoma. However, comparing only atypical nevi and melanoma lesions the frequency of BRAF mutation is significantly greater in male (78%) than female (35%) patients (P = 0.0194). The previously described T1796A point mutation was detected in 17 of 18 mutated samples, and a novel mutation consisting of a substitution of valine for lysine (GT1795-96AA) was detected in one melanoma case. Our findings of a high frequency of BRAF mutations at codon 599 in benign melanocytic lesions of the skin indicate that this mutation is not sufficient by itself for malignant transformation.

DNA, Neoplasm↗

PubMed2006

Survivin expression in pancreatic intraepithelial neoplasia (PanIN): steady increase along the developmental stages of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDA) is one of the most aggressive gastrointestinal cancers and is thought to arise from noninvasive precursors-pancreatic intraepithelial neoplasia (PanIN). Aberrantly prolonged cell survival due to apoptosis suppression is likely to contribute to carcinogenesis and carcinoma progression where the inhibitor of apoptosis proteins (IAPs) may play an important role. IAPs specifically inhibit caspases 3, 7, and 9 and prevent apoptosis. Survivin is a unique member of the IAPs family that is expressed in most human cancers including PDA but is not expressed in most normal adult tissues. To measure survivin transcript levels in normal pancreatic ducts, PanINs, and PDA, we used laser capture microdissection and real-time polymerase chain reaction. Survivin protein expression in normal pancreatic ducts, PanINs, PDA, and its metastases to lymph nodes were evaluated by immunohistochemistry. In microdissected tissues, we found a steady and close to exponential increase in survivin transcript levels from low-grade lesions (PanINs-1) to high-grade lesions (PanINs-2 and 3) and further to PDA. This observation was strictly mirrored by survivin protein expression. In addition, survivin was localized to the nucleus in high-grade lesions (starting at PanIN-2 stage), PDA, and nodal metastases, suggesting that nuclear translocation of survivin may be an early event in transformation to malignancy.

Biomarkers, Tumor↗

PubMed2005

Histology-based expression profiling yields novel prognostic markers in human glioblastoma.

Although the prognosis for patients with glioblastoma is poor, survival is variable, with some patients surviving longer than others. For this reason, there has been longstanding interest in the identification of prognostic markers for glioblastoma. We hypothesized that specific histologic features known to correlate with malignancy most likely express molecules that are directly related to the aggressive behavior of these tumors. We further hypothesized that such molecules could be used as biomarkers to predict behavior in a manner that might add prognostic power to sole histologic observation of the feature. We reasoned that perinecrotic tumor cell palisading, which denotes the most aggressive forms of malignant gliomas, would be a striking histologic feature on which to test this hypothesis. We therefore used laser capture microdissection and oligonucleotide arrays to detect molecules differentially expressed in perinecrotic palisades. A set of RNAs (including POFUT2, PTDSR, PLOD2, ATF5, and HK2) that were differentially expressed in 3 initially studied, microdissected glioblastomas also provided prognostic information in an independent set of 28 glioblastomas that did not all have perinecrotic palisades. On validation in a second, larger independent series, this approach could be applied to other human glioma types to derive tissue biomarkers that could offer ancillary prognostic and predictive information alongside standard histopathologic examination.

Biomarkers, Tumor↗

PubMed2005

Keratinocyte growth factor-1 expression in healthy and diseased human periodontal tissues.

OBJECTIVES: Keratinocyte growth factor-1 (KGF-1) is up-regulated in chronic inflammation and specifically stimulates epithelial cell proliferation by signaling through the epithelial-specific keratinocyte growth factor receptor (KGFR). We examined KGF-1 and KGFR protein and gene expression in healthy and diseased periodontal tissues. METHODS: Tissues were collected from patients with periodontal health or disease, immediately frozen and stained for KGF-1 and KGFR protein expression. Laser capture microdissection of epithelial and connective tissue cells with reverse transcription-polymerase chain reaction (RT-PCR) examined KGF-1 and KGFR gene expression profiles and enzymatic digestion with heparitinase, chondroitinase ABC or pre-treatment with suramin examined epithelial surface molecule interactions with KGF-1. RESULTS: In tissues collected from healthy patients, KGF-1 protein localized to areas of junctional and basal oral epithelial cells and was significantly increased in periodontal pocket epithelium (p<0.01) and in the oral epithelium (p<0.05) of disease-associated tissues. KGFR localized to the junctional and the parabasal cells of oral epithelium, with the relative staining intensity being increased in disease-associated pocket epithelium (p<0.05). Laser capture microdissection with RT-PCR confirmed KGF-1 and KGFR were specifically expressed by connective tissue and epithelium, respectively. KGF-1 localization to epithelial cells was largely eliminated by suramin pre-treatment, indicating interaction with the KGFR. CONCLUSIONS: KGF-1 and KGFR proteins are expressed in healthy periodontal tissues but significantly increased in diseased periodontal tissues. We hypothesize up-regulation of KGF-1 and KGFR protein associated with disease regulates epithelial cell behavior associated with onset and progression of periodontal pocket formation.

Fibroblast Growth Factor 7↗

PubMed2006

Corticotropin-releasing hormone receptor expression on normal and tumorous human adrenocortical cells.

Corticotropin-releasing hormone (CRH) is not only the principal regulator of the central hypothalamic-pituitary-adrenal (HPA) axis but also exerts direct actions on peripheral tissues. We analyzed the expression of CRH receptors in microdissected preparations of normal human adrenal glands and in adrenocortical and adrenomedullary tumors, employing immunohistochemistry, quantitative RT-PCR of microdissected adrenal tissues, and in situ hybridization. The effect of CRH on adrenal steroidogenesis was tested in adrenal cells. Immunoreactive CRH1R was found primarily within the zona reticularis. In addition, we found a higher expression of CRH type-1 and 2 receptors mRNAs in preparations of adrenal cortices as compared to pheochromocytomas, a 6-fold increase in preparations of clinically unapparent adrenocortical adenomas, and a 10- to 60-fold increase in cortisol-producing adrenal adenomas. Stimulation of the adrenal tumor cell line NCI-H295R with CRH elicited a 1.4-fold increase in DHEA secretion. This result could be reproduced in a culture of primary human adrenocortical cells. We conclude that adrenocortical cells exhibit a higher expression of functional CRH receptors than chromaffin cells and that CRH acts on adrenal DHEA production. The data support the assertion of a direct action of CRH on human adrenocortical cells in addition to an intra-adrenal CRH receptor/adrenocorticotropin system. Enhanced CRH1R expression may be involved in adrenocortical tumorigenesis.

Adrenal Cortex↗

PubMed2004

Endometrial glandular dysplasia: a putative precursor lesion of uterine papillary serous carcinoma. Part II: molecular features.

Endometrial glandular dysplasia (EmGD) may be a newly defined precursor lesion of uterine papillary serous carcinoma (UPSC) by morphology. In this report, we studied molecular changes present in EmGD by the loss of heterozygosity (LOH) approach using laser capture microdissected tissue samples. Nineteen uteri showing at least 1 focus of EmGD by morphology were selected. These cases were 12 UPSC, 2 clear cell carcinomas, 1 mixed uterine papillary serous and endometrioid carcinoma, 1 uterine carcinosarcoma, 1 serous endometrial intraepithelial carcinoma (EIC), and 2 EmGD involving endometrial polyps. Seven microsatellite polymorphic DNA markers (TP53 at 17p, D1S211, and D1S162 at 1p32, D17S1323 at 17q21, D17S1330 at 17q25, D5S346 at 5q, and D2S123 at 2p) were utilized. A total of 123 laser-captured microdissection samples from 19 cases was studied with LOH method. The frequencies and patterns of LOH were analyzed and compared among benign resting endometrium (RE), EmGD, serous EIC, and UPSC. LOH was observed for at least 1 of the 7 markers in all categories of lesions, EmGD, serous EIC, and UPSC. The frequency of LOH for EmGD ranged from 4.2% to 31.3%; the range for serous EIC was 5.9% to 78.6%; and that for UPSC was 7.7% to 62.5%. The most frequent LOH in the 3 above-cited categories of lesions was identified at 17p (TP53) and 1p (D1S162). The frequency of LOH in EmGD with markers of TP53 and D1S162 was significantly higher than in RE (p < 0.05). With markers of D1S211 and D2S123, LOH in EmGD was higher than RE, approaching to a statistically significant level. Compared with foci of serous EIC and UPSC, however, the rate of LOH in EmGD was significantly lower only with TP53 locus (31.3% vs more than 60%, p < 0.05). The difference of LOH frequency with other chromosomal markers between EmGD and serous EIC/UPSC did not reach a statistically significant level. A significantly high concordant LOH pattern was found between foci of EmGD and serous EIC/UPSC (p = 0.05). We conclude that EmGD frequently shows LOH at multiple chromosomal loci, particularly at 17p and 1p. Significantly high concordant LOH frequency between EmGD and paired serous EIC or UPSC strongly suggests that EmGD is a noncancerous precursor lesion of UPSC, probably also of serous EIC. The clinical significance of EmGD needs further studies.

Aged↗

PubMed2005

Loss of heterozygosity on chromosome 1 and 9 and hormone receptor analysis of metastatic malignant melanoma presenting in breast.

Malignant melanoma (MM), the most common metastatic solid tumor to involve the breast, may present as a diagnostic problem, frequently requiring the use of ancillary studies for accurate diagnosis. The implication of hormonal interplay is strong since metastatic MM to the breast is seen nearly always in women. However, the role of hormonal status as a predisposing factor in the development of this entity is largely unresolved. A number of chromosomal loci, including 1p36 and 9p21-22, appear to harbor critical genes important to melanoma tumorigenesis, and additionally chromosome 9q22.3-31. We wanted to know if metastatic MM in breast showed chromosome 1p and 9p genetic alterations (loss of heterozygosity) similar to those that occur in primary cutaneous MM, and whether additional 9q LOH changes are present. Hormonal receptor status of the metastatic MM was also determined. We identified 20 patients with known MM metastatic to the breast, which we analyzed with the following genetic markers: D9S12 (9q22.3), D9S171 (9p21), IFNA (9p22), and D1S450 (1p). Visually directed microdissection was performed on archival histologic slides containing both tumor and adjacent normal breast epithelium, followed by single-step DNA extraction and polymerase chain reaction (PCR) amplification for evaluation of loss of heterozygosity (LOH) for the above-listed markers. Immunohistochemical (IHC) stains for estrogen receptor (ER) and progesterone receptor (PR) was performed on 10 of the cases. Twelve of the 20 cases contained DNA suitable for PCR amplification following direct visualization microdissection. Four of 8 (50%) informative cases showed LOH at 9p21 with D9S171. Ten cases were heterozygous for IFNA, with 2 cases (20%) showing LOH at this locus. These particular cases also showed LOH at 9p21. One of 9 (11%) informative cases showed LOH for D1S450 (1p36). Five cases were heterozygous for D9S12, and 2 (40%) showed LOH in the tumor at 9q22.3. IHC stains for ER and PR were negative in the 10 tumors studied. Metastatic MM presenting as a breast mass is an interesting entity often requiring IHC studies for diagnosis, particularly when the histologic features simulate breast carcinoma or when no primary tumor is known. These tumors are ER and PR negative. Metastatic MM involving the breast shows similar genetic allelic losses on chromosome 9p21-22 (50%) and 1p36 (11%), as previously described in primary cutaneous MM. Additional LOH was observed at the 9q22.3-31 locus (40%). We suggest this locus to be investigated for harboring potential genes important in the tumorigenesis of cutaneous MM.

Adult↗