Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Microdissection”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 505 records · Page 28Linked to original sources
PubMed2000

PCR artifacts in LOH and MSI analysis of microdissected tumor cells.

Polymerase chain reaction (PCR) analysis to study loss of heterozygosity (LOH) and microsatellite instability (MSI) in tumors is widely used. Microdissection techniques are applied to obtain tumor-specific tissue cells. By microdissection, however, the amount of template DNA extracted may vary considerably and interfere with optimal PCR amplification. To circumvent LOH and MSI misinterpretations due to low DNA input, we have assessed the critical level of DNA input for reliable PCR analysis. PCR analysis was performed by using 18 polymorphic markers (mono-, di-, tri-, and tetranucleotide) on DNA derived from both paraffin-embedded, formalin-fixed, and fresh frozen tumor specimens at template input levels ranging from 0.05 to 25.0 ng. We show a highly significant relation between DNA input and the occurrence of LOH and MSI artifacts. Furthermore, for DNA extracted from paraffin-embedded material, the percentage of LOH artifacts is significantly higher compared with DNA extracted from frozen tissue. For reliable PCR analyses using a mono-, di-, tri-, or tetranucleotide marker, a minimum of 10.0 ng DNA is required when DNA is isolated from formalin-fixed, paraffin-embedded tissue and 5.0 ng when isolated from fresh frozen tissue. HUM PATHOL 31:1414-1419.

Alleles↗
PubMed2001

The detection of p53 gene mutation using a microdissection technique in primary intracranial germ cell tumors.

Using a microdissection technique, the contribution of the p53 mutation to tumorigenesis and prognosis in each histological subtype of the intracranial germ cell tumors (GCTs) was evaluated. Nineteen patients had primary intracranial GCTs, including 4 germinomas (GEs), 4 teratomas (TEs), 1 mixed tumor of GE and TE, and 10 mixed GCTs containing non-germinomatous malignant germ cell tumors (NG-MGCTs). After microdissection of specific subtypes, genomic DNA was screened for mutations in exons 5-8 of the p53 gene, using the dideoxyfingerprinting (ddF) followed by direct DNA sequencing. The direct sequencing revealed a total of six mutations in PCR products derived from the five cases (26%) which showed mobility shifts in ddF. Among the six mutations detected, four were missense mutations and two were silent. Missense mutations of the p53 gene tended to occur more frequently in the NG-MGCT component than in the GE or TE components (3/15 vs. 1/12 vs. 0/13). The incidence of missense mutations was not different between the survivors (3/13) and the deceased (1/6). This study suggests the possible role of the p53 gene in the tumori-genesis of NG-MGCT. However, p53 gene mutation did not correlate with the prognosis of NG-MGCT.

Adult↗
PubMed1996

Acute effects of morphine on Substance P concentrations in microdissected regions of guinea-pig brain.

The present study investigated the effects of acute morphine treatment and of naloxone-induced morphine withdrawal on Substance P (SP) concentrations in microdissected regions of the guinea-pig brain. Guinea-pigs, which were treated with a single dose of morphine sulphate (15mg/kg s.c.), received naloxone hydrochloride (15mg/kg s.c.) after 2h. Control animals received injections of saline, saline and naloxone, or morphine and saline. Locomotor and behavioural activities were measured throughout the experiments. Animals were killed 0.5h after naloxone administration, brains were removed and SP-like immunoreactivity (SP-LI) was measured in microdissected regions using radioimmunoassay. Morphine significantly increased the concentration of SP-LI in the central nucleus of the amygdala, but reduced SP-LI overall in the mesencephalon. Guinea-pigs pretreated with morphine and then given naloxone to precipitate withdrawal showed no change in SP-LI concentrations in any brain region, compared with control animals, despite an increase in locomotor activity and other behaviours characteristic of opioid withdrawal in guinea-pigs.

Journal Article↗
PubMedDate not supplied

The role of tissue microdissection in cancer research.

Tissue microdissection is a laboratory method that is used to procure specific cells or cell populations from a histology slide under direct microscopic visualization. The recovered cells can be studied with a variety of DNA, messenger RNA, and protein analysis methods, including new high-throughput gene expression and proteomics technologies. This approach is permitting investigators to comprehensivelyexamine the molecular anatomy of cells in tissue sections forthe first time. This article reviews the development and evolution of tissue microdissection techniques, summarizes examples of research studies, and discusses related challenges that the research community must address. Additional information and complete laboratory protocols are available on a website at http://cgap-mf.nih.gov/.

DNA, Neoplasm↗
PubMed2001

Identification and validation of P311 as a glioblastoma invasion gene using laser capture microdissection.

The mRNA expression profiles from glioblastoma cells residing at the tumor core and invasive rim of a human tumor resection were compared. From a single tumor specimen, 20,000 single cells from each region were collected by laser capture microdissection. Differential expression of 50-60 cDNA bands was detected. One of the sequences overexpressed by the invasive cells showed 99% homology to the P311 gene, the protein product of which is reported to localize at focal adhesions. Relative overexpression of P311 by invading glioblastoma cells compared with tumor core was confirmed by quantitative reverse transcription-PCR of six glioblastoma specimens after laser capture microdissection collection of rim and core cells. In vitro studies using antisense oligodeoxynucleotides and integrin activation confirmed the role of P311 in supporting migration of malignant glioma cells. Immunochemistry studies confirmed the presence of the P311 protein in tumor cells, particularly at the invasive edge of human glioblastoma specimens.

Amino Acid Sequence↗
PubMed2002

Analysis of microdissected prostate tissue with ProteinChip arrays--a way to new insights into carcinogenesis and to diagnostic tools.

Prostate carcinomas are one of the most common malignancies in western societies. The pathogenesis of this tumor is still poorly understood. These tumors present with two characteristic features: epithelial-mesenchymal interactions, which play a pivotal role for tumor development and most of clinically manifest cancers arise in prostate proper compared to a minority of tumors which develop in the transitional zone. Deciphering the epithelial-mesenchymal cross talk and identification of molecular pecularities of the sub-populations of cells in different zones can therefore help understanding carcinogenesis and development of new, non-invasive tools for the diagnosis and prognosis of prostate carcinomas which has remained a challenge until today. A ProteinChip array technology (SELDI = surface enhanced laser desorption ionization) has been developed recently by Ciphergen Biosystems enabling analysis and profiling of complex protein mixtures from a few cells. This study describes the analysis of approximately 500-1000 freshly obtained prostate cells by SELDI-TOF-MS (surface enhanced laser desorption ionization time-of-flight mass spectrometry). Pure cell populations of stroma, epithelium and tumor cells were selected by laser assisted microdissection. Multiple specific protein patterns were reproducibly detected in the range from 1.5 to 30 kDa in 28 sub-populations of 4 tumorous prostates and 1 control. A specific 4.3 kDa peak was increased in the prostate tumor stroma compared to normal prostate proper and transitional zone stroma and increased in prostate tumor glands compared to normal prostate proper and transitional zone glands. Coupling laser assisted microdissection with SELDI provides tremendous opportunities to identify cell and tumor specific proteins to understand molecular events underlying prostate carcinoma development. It underlines the vast potential of this technology to better understand pathogenesis and identify potential candidates for new specific biomarkers in general which could help to screen for and distinguish disease entities, i.e. between clinically significant and insignificant carcinomas of the prostate.

Aged↗
PubMed2002

Identification of cyclin D1 mRNA overexpression in B-cell neoplasias by real-time reverse transcription-PCR of microdissected paraffin sections.

PURPOSE: Overexpression of cyclin D1 mRNA and protein as a result of the chromosomal translocation t(11;14)(q13;q32) is a highly specific molecular marker of mantle cell lymphoma, but cyclin D1 dysregulation can also be found in other B-cell neoplasias. The aim of the study was to develop a precise and reliable tool for quantitation of cyclin D1 mRNA suitable for archival clinical specimens. EXPERIMENTAL DESIGN: A real-time reverse transcription-PCR (RT-PCR) assay was used to quantitate cyclin D1 mRNA copy numbers. Using 2000 microdissected cells as template, 104 formalin-fixed, paraffin-embedded lymph node, spleen, and decalcified bone marrow biopsies from a panel of 95 cases of B-cell non-Hodgkin's lymphomas (B-NHLs) were analyzed. In addition, cyclin D1 protein expression was assessed by immunohistochemistry. RESULTS: Strong cyclin D1 mRNA overexpression was detected in mantle cell lymphomas (23 of 23), hairy cell leukemias (5 of 19), and multiple myelomas (7 of 23) with particularly high levels in 2 of the latter cases. Intermediate transcript levels were found in 5 of 23 multiple myelomas and 7 of 19 hairy cell leukemias. B-cell chronic lymphocytic leukemias (10 of 10), follicular lymphomas (9 of 9), mucosa-associated lymphoid tissue lymphomas (5 of 5) and reactive lymphoid tissues with the exception of normal spleen had no or very low cyclin D1 expression. In comparison with real-time RT-PCR, immunohistochemistry showed a lower level of sensitivity, more variability, and did not allow accurate quantitation. CONCLUSIONS: Real-time RT-PCR for cyclin D1 mRNA is an excellent tool for the differential diagnosis of B-NHLs and, in combination with microdissection, a powerful approach for retrospective trials using archival clinical specimens as tissue source. Furthermore, real-time RT-PCR may help to identify subgroups of B-NHLs according to cyclin D1 mRNA copy numbers and to investigate the possible influence of different chromosomal breakpoints on cyclin D1 expression.

Chromosomes, Human, Pair 11↗
PubMed2002

[Sharper diagnostic tool the future promise of laser-assisted microdissection].

The paper describes the use of laser-assisted microdissection to retrieve microscopically defined cell populations including single cells from tissue sections for subsequent analysis of genomic DNA and mRNA. A general background is given on the techniques available and requirements for PCR based on minute templates. Different pre-PCR approaches are briefly described and possibilities and limitations of using archival material compared to fresh frozen tissue are discussed. In the article we give one example on how we have used the PALM laser microscopy system in combination with a nested, multiplex PCR system to analyze single normal keratinocytes as well as tumor cells from a case of basal cell cancer. We found that p53 mutations are common in normal, chronically sun-exposed skin. Widespread yet common mutations in the p53 gene that were unrelated to immunoreactivity for the p53 antibody were found in tumor cells. In addition there were rare mutations in occasional tumor cells that apparently did not result in selective growth advantage. Perspectives for the future are presented and the potential of laser assisted microdissection is highlighted within the fields of cancer research, developmental studies as well as studies of inflammatory and degenerative diseases. The combination of a method that allows careful selection of defined cells with powerful micro array based techniques, provides a setting with potential to uncover pathogenic mechanisms for large variety of human diseases.

Cytological Techniques↗
PubMed2002

Loss of heterozygosity at microsatellite markers from region p11-21 of chromosome 8 in microdissected breast tumor but not in peritumoral cells.

Alterations of chromosomal region 8p11-21 are very frequent in human cancers, and especially in breast cancer; yet, most of the genes involved have not been identified. We performed laser capture microdissection in a series of 52 consecutive breast tumor samples to obtain pure tumor cells without surrounding normal breast. To determine genomic subregions in which some of the cancer genes may be located, we conducted a search for loss of heterozygosity (LOH) at 13 microsatellite markers from this region. Two-thirds of the tumors showed LOH at least at one marker. Microdissection of pure tumor samples was helpful to precisely define four LOH subregions. No LOH was observed in the corresponding peritumoral tissues. We studied by immunohistochemistry (IHC) on tissue-microarrays the expression in the same tumors, of the protein product of three potential tumor genes lying close to or within the subregions of LOH. In most samples, the TACC1 gene product was downregulated in tumor cells as compared to normal cells. Our results show that the centromeric portion of chromosome arm 8p is frequently altered in breast tumor cells.

Breast Neoplasms↗
PubMed2002

[Microdissection and PCR-SSCP detected mutation and expression of p53 and K-ras gene in carcinogenesis and development of induced rat lung carcinoma].

OBJECTIVE: To investigate the roles of p53 and K-ras gene in carcinogenesis and development of the lung carcinoma induced by 3-methylcholanthrene (MCA) and diethylinitrosamine (DEN) in Wistar rats, and to elucidate the relationships between the protein expression and gene mutation of p53 and K-ras. METHODS: Microdissection was used to obtain pure cell populations of each phase in the carcinogenesis and development of lung carcinoma induced by MCA and DEN. DNA of the microdissected cell populations was extracted and used to analyze the mutations of p53 exons 5 approximately 8 and K-ras exons 1 approximately 2 by PCR-SSCP. The expressions of p53 and K-ras protein in each phase were detected by immunohistochemistry. RESULTS: No mutation and protein expression of p53 and K-ras was found in the 30 cases with normal bronchial epithelium. Mutation of p53 was detected in 3.1% of 18 hyperplasia and 14 squamous metaplasia cases, 28.6% of 21 dysplasia, 30.0% of 12 carcinomas in situ, 51.2% of 43 infiltration carcinomas, 52.9% of 17 metastases. The positive immunostaining rate of p53 protein was 0, 42.9%, 50.0%, 60.5% and 64.7% respectively. K-ras mutation rate was 0, 4.8%, 8.3%, 9.3%, 11.8% respectively, while the overexpression rate of K-ras protein was 15.6%, 19.0%, 25.0%, 41.9%, 52.9% respectively. p53 protein expression was closely related with p53 mutation (P < 0.005, Pearson's R = 0.599 6). There was no relationship between the protein expression and gene mutation of K-ras (P > 0.500). CONCLUSIONS: p53 gene mutation and K-ras overexpression were early events in the carcinogenesis and development of rat lung carcinoma induced by MCA and DEN, while K-ras mutation does not play any important role.

Animals↗
PubMed1999

[Microdissection of M chromosome in Vicia faba and its library construction].

Microdissection and microcloning technique was employed to construct the library of M chromosome in Vicia faba. The M chromosomes were microdissected with a micromanipulator and were put into a 0.5 ml Eppendorf tube, then digested with Sau3A. Sau3A linker adaptors were ligated to the end of chromosome DNA fragments, and two rounds of PCR were carried out with one chain of linker adaptor as the primer. The PCR products ranged in size from 300 base pair (bp) to 3000 bp with predominant fragments from 500 bp to 1500 bp. Southern hybridization analysis confirmed that PCR products originated from Vicia faba genome. The second round PCR products were cloned and about 102,000 recombinants were obtained. 118 recombinants were selected randomly for analysis. The inserts ranged in size from 150 bp to 3000 bp with an average of 690 bp. Dot blot was carried out for 100 clones with DIG labeled Vicia faba genome DNA as probes. The result revealed that 51% were low and unique copy sequences, 49% were repetitive sequences. M chromosome DNA library has not been reported before.

Chromosome Mapping↗
PubMed2003

Loss of cellular retinol-binding protein 1 gene expression in microdissected human ovarian cancer.

PURPOSE: We have previously found that cellular retinol-binding protein 1 (CRBP1),involved in retinol transport and metabolism, is down-regulated in an in vitro rat model of ovarian cancer and in several human ovarian cancer cell lines. The aim of this study was to determine the clinical relevance of this change to human ovarian cancer. EXPERIMENTAL DESIGN: A cohort of 48 frozen human serous ovarian carcinomas was evaluated for CRBP1 gene expression. Malignant ovarian epithelial cells were selectively procured by laser capture microdissection, and their CRBP1 expression was determined by real-time PCR. Immunohistochemistry for CRBP1 was performed on paraffin sections of ovarian tumors using polyclonal affinity-purified rabbit anti-CRBP1 antibody. RESULTS: In 35% of ovarian cancer patient samples, there was no detectable CRBP1 expression by real-time PCR. The expression of CRBP1 in microdissected serous ovarian carcinomas was not related to either tumor stage (P = 0.6839) or grade (P = 0.9599). Quantitative PCR results were confirmed by immunohistochemistry using an antibody against CRBP1. CONCLUSIONS: The loss of CRBP1 expression in clinical ovarian tumor specimens is consistent with our previous findings in the rat model and human ovarian cancer cell lines. It appears to be an early event in ovarian carcinogenesis because there was no statistically significant difference in its frequency between tumor stages and grades. Our findings suggest that the loss of CRBP1 expression contributes to the ovarian cancer oncogenesis via altered vitamin A metabolism.

Activating Transcription Factor 2↗
PubMed1992

Frequency and significance of cervicomediastinal lymph node metastases in medullary thyroid carcinoma: results of a compartment-oriented microdissection method.

The frequency and significance of cervicomediastinal lymph node metastases have been investigated in 82 medullary thyroid carcinoma (MTC) patients retrospectively comparing two surgical techniques of lymph node dissection: selective lymphadenectomy (n = 63) versus compartment-oriented microdissection (n = 35). No positive correlation was observed between primary tumor size and the number of lymph node metastases. In patients with lymph node metastases proven histologically, 42% showed only cervical involvement (35% unilateral--type A, 7% bilateral--type B) and 22% cervicomediastinal lymph node involvement (15% cervico-unilateral and mediastinal--type C, 7% cervicobilateral and mediastinal--type D). Biochemical cure was 83% in node-negative patients but only 21% in node-positive patients. In node-positive MTC, calcitonin normalization was achieved in none with bilateral lymph node involvement but only in those unilateral lymph node metastases (31% in type A, 17% in type C). Survival and biochemical cure are significantly improved by application of the compartment-oriented microdissection method more so at primary surgery than at reoperation.

Carcinoma↗
PubMedDate not supplied

ProteinChip Array analysis of microdissected colorectal carcinoma and associated tumor stroma shows specific protein bands in the 3.4 to 3.6 kDa range.

Multiple pathways of carcinogenesis have been associated with colorectal carcinomas, including the adenoma-carcinoma sequence. The non polyposis coli gene has also been implicated in the pathogenesis of these tumors. Identification of the epithelial-mesenchymal interaction may help in understanding the pathways of invasion and may lead to the development of new, non-invasive tools for the diagnosis and prognosis of colon carcinomas. A ProteinChip Array technology (SELDI=Surface Enhanced Laser Desorption Ionization) has been developed enabling analysis and profiling of complex protein mixtures from a few cells. This study describes the protein analysis of approximately 500-1000 freshly obtained cells from normal and malignant colonic epithelium and its associated stroma by SELDI-TOF-MS (Surface Enhanced Laser Desorption Ionization Time-of-Flight Mass Spectrometry). Pure cell populations of normal and malignant epithelium as well as stroma (without tumor cells) were selected by microdissection from 9 patients. A pattern of 3 peptides of 3.48, 3.55 and 3.6 kDa, which were increased in the colon tumor epithelium and stroma compared to associated normal colon and stroma in all 9 patients, was observed. Coupling microdissection with SELDI represents a powerful tool to identify cell and tumor specific proteins and to understand molecular events underlying the invasive event in colorectal carcinomas. The presence of certain proteins in invasive carcinomas may lead to the development of non invasive biomarkers for the identification or detection of recurrence of colorectal malignancies.

Adenocarcinoma↗
PubMed2005

Optimal molecular profiling of tissue and tissue components: defining the best processing and microdissection methods for biomedical applications.

Isolation of well-preserved pure cell populations is a prerequisite for sound studies of the molecular basis of pancreatic malignancy and other biological phenomena. This chapter reviews current methods for obtaining anatomically specific signals from molecules isolated from tissues, a basic requirement for productive linking of phenotype and genotype. The quality of samples isolated from tissue and used for molecular analysis is often glossed-over or omitted from publications, making interpretation and replication of data difficult or impossible. Fortunately, recently developed techniques allow life scientists to better document and control the quality of samples used for a given assay, creating a foundation for improvement in this area. Tissue processing for molecular studies usually involves some or all of the following steps: tissue collection, gross dissection/identification, fixation, processing/embedding, storage/archiving, sectioning, staining, microdissection/annotation, and pure analyte labeling/identification. High-quality tissue microdissection does not necessarily mean high-quality samples to analyze. The quality of biomaterials obtained for analysis is highly dependent on steps upstream and downstream from tissue microdissection. We provide protocols for each of these steps, and encourage you to improve upon these. It is worth the effort of every laboratory to optimize and document its technique at each stage of the process, and we provide a starting point for those willing to spend the time to optimize. In our view, poor documentation of tissue and cell type of origin and the use of nonoptimized protocols is a source of inefficiency in current life science research. Even incremental improvement in this area will increase productivity significantly.

Coloring Agents↗
PubMed2005

Distinct chromosomal aberrations of ampulla of Vater and pancreatic head cancers detected by laser capture microdissection and comparative genomic hybridization.

Despite the continuous progress in molecular methodology, the genetic events involved in the carcinogenesis of pancreatic head ductal carcinomas (PHDCs) and ampulla of Vater cancer (AVC) remain largely unknown. Their proximity within the confined region lends them to very similar clinical presentations and operative approaches. However, it is unclear why AVC has a significantly better outcome than PHDCs. The drastic difference may arise from the distinct tumor origins. Therefore, the study of genetic alterations within these two neighboring tumors may elucidate their mechanisms. However, previous genetic analysis of PHDCs may have been influenced by contamination of excessive stromal and inflammatory cells in the background. To date, most comparative genomic hybridization (CGH) studies of pancreatic cancer are based in cell lines or specimens that were not microdissected. Even AVC has a paucity of data. To determine the differences of the genetic alterations of PHDCs and AVC, we used laser capture microdissection combined with degenerated oligonucleotide polymerase chain reaction and CGH to identify the chromosomal aberrations. Frequent gains were found on 5p, 13q, 3q, 8q, 1p, 2p, 2q, 3q, 7p, 8p, 9p, 13q, and 21q, while frequent losses were located on 7p, 18q, 1p, 11q, 16q, 19q, 1q, 2q, 3p, 19p, and 17p in PHDCs. In AVC, chromosomal gains occurred frequently in 7p, 8q, 1q, 2q, 3p, 4p, 7p, 3q, 5p, 20p, 20q, 4q, 5q, 7q, 11p, 12p, 13q, 14q, 18p, 18q, 21q, 9p, 10p, and 15q, and losses frequently in 17q, 1p, 18q, 19p, 5q, 10p, and 10q. This is the first report on the CGH profiles of AVC. These data provide evidence that chromosomal gains/amplifications of AVC differ from those of PHDCs. Among them, chromosomal gains on 1q25, 7p15, 8q23, and 3p21, and losses on 17q24, were statistically higher in AVC than PHDCs (P<0.05). The gains and losses suggest possible putative tumor suppressors and oncogenes that may be involved in the different carcinogenic pathways of AVC.

Adult↗
PubMed1991

[Technique for the microdissection of human high resolution chromosome subsequent polymerase chain reaction and microcloning].

In this paper is reported a simple technique for the microdissection of specific regions of human high resolution chromosome subsequent PCR and microcloning. This technique was successfully used to microdissect 4 chromosomal pieces from the distal one third from band 11.2 to the terminal of the short arm of Y chromosome where the testis determining factor located, PCR 30 cycles, and obtained 3.6 x 10(4) clones. This technique the highlight to establish a gene library of many specific regions of human chromosome hereafter.

Cloning, Molecular↗
PubMed1991

Microdissection of human high resolution banded chromosome, polymerase chain reaction and microcloning.

A simple technique for microdissection of specific region of human high resolution banded chromosome, followed by polymerase chain reaction (PCR), and microcloning was successfully used to microdissect 4 chromosomal pieces from the distal one third from band 11.2 to the terminal of the short arm of Y chromosome where the testis determining factor is located; 3.6 x 10(4) clones were obtained after 30 cycles of PCR. We analysed 41 clones with insert. The size of insert ranges from 140 to 350 bp (average 250 bp). A Southern blot analysis was done for one of them, and a 2.5 kb Hind III fragment was detected.

Cloning, Molecular↗