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Screening technologies for target identification in pancreatic cancer.

Michl P, Ripka S, Gress T, Buchholz M - Cancers (Basel) (2010)

Bottom Line: More than a decade ago, microarray technology was introduced to identify differentially expressed genes in pancreatic cancer as compared to normal pancreas, chronic pancreatitis and other cancer types located in close proximity to the pancreas.In addition, proteomic screens have facilitated the identification of differentially secreted proteins in body fluids of pancreatic cancer patients, serving as possible biomarkers.Recently, RNA interference-based loss-of-function screens have been used to identify functionally relevant genes, whose knock-down has impact on pancreatic cancer cell viability, thereby representing potential new targets for therapeutic intervention.

View Article: PubMed Central - PubMed

Affiliation: Department of Gastroenterology and Endocrinology, University Hospital, Philipps-University Marburg, Baldinger Strasse, D-35043 Marburg, Germany. michlp@med.uni-marburg.de.

ABSTRACT
Pancreatic cancer exhibits an extraordinarily high level of resistance to almost any kind of systemic therapy evaluated in clinical trials so far. Therefore, the identification of novel therapeutic targets is urgently required. High-throughput screens have emerged as an important tool to identify putative targets for diagnosis and therapy in an unbiased manner. More than a decade ago, microarray technology was introduced to identify differentially expressed genes in pancreatic cancer as compared to normal pancreas, chronic pancreatitis and other cancer types located in close proximity to the pancreas. In addition, proteomic screens have facilitated the identification of differentially secreted proteins in body fluids of pancreatic cancer patients, serving as possible biomarkers. Recently, RNA interference-based loss-of-function screens have been used to identify functionally relevant genes, whose knock-down has impact on pancreatic cancer cell viability, thereby representing potential new targets for therapeutic intervention. This review summarizes recent results of transcriptional, proteomic and functional screens in pancreatic cancer and discusses potentials and limitations of the respective technologies as well as their impact on future therapeutic developments.

No MeSH data available.


Related in: MedlinePlus

Overview on the use of RNAi libraries in different screening approaches for tumor-relevant read-outs.
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f1-cancers-03-00079: Overview on the use of RNAi libraries in different screening approaches for tumor-relevant read-outs.

Mentions: RNA interference can be introduced into mammalian cells either by transfection of double-stranded small-interfering RNAs (siRNA) or by transfection or transduction of short-hairpin RNA containing plasmids (shRNA) which are transcribed and subsequently cleaved intracellularly into effective siRNA oligonucleotides by the enzyme Dicer [47]. For screening approaches, RNA interference collections for parallel knock-down of multiple genes are utilized, which may range from gene families of interest (e.g., “Kinome library”) up to genome-wide libraries [50]. These collections contain libraries of siRNA oligonucleotides or shRNA plasmids. Both variants offer distinct advantages and disadvantages, which have to be considered when considering a screen set-up: siRNA libraries allow only transient suppression of the gene of interest, whereas shRNA plasmids containing selection markers can be transfected or transduced stably to allow permanent gene suppression, making long-term assays feasible. In contrast, knock-down efficiency of the gene of interest is frequently more pronounced after siRNA transfection compared to shRNA [51]. Screens may be performed as arrays in 96- or 384-well plate formats with one gene being silenced per well. After introduction of the siRNAs, these plates can be evaluated for many cellular features such as viability, apoptosis, motility, transcriptional activation of distinct pathways using luciferase-based read-outs or cell morphology using high-throughput microscopy (Figure 1). Alternatively, screens may also be performed by transfecting or transducing pooled shRNA-plasmids with selection markers. After selecting transfected cells, enrichment or depletion of distinct shRNAs can be analyzed by high-throughput sequencing.


Screening technologies for target identification in pancreatic cancer.

Michl P, Ripka S, Gress T, Buchholz M - Cancers (Basel) (2010)

Overview on the use of RNAi libraries in different screening approaches for tumor-relevant read-outs.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3756350&req=5

f1-cancers-03-00079: Overview on the use of RNAi libraries in different screening approaches for tumor-relevant read-outs.
Mentions: RNA interference can be introduced into mammalian cells either by transfection of double-stranded small-interfering RNAs (siRNA) or by transfection or transduction of short-hairpin RNA containing plasmids (shRNA) which are transcribed and subsequently cleaved intracellularly into effective siRNA oligonucleotides by the enzyme Dicer [47]. For screening approaches, RNA interference collections for parallel knock-down of multiple genes are utilized, which may range from gene families of interest (e.g., “Kinome library”) up to genome-wide libraries [50]. These collections contain libraries of siRNA oligonucleotides or shRNA plasmids. Both variants offer distinct advantages and disadvantages, which have to be considered when considering a screen set-up: siRNA libraries allow only transient suppression of the gene of interest, whereas shRNA plasmids containing selection markers can be transfected or transduced stably to allow permanent gene suppression, making long-term assays feasible. In contrast, knock-down efficiency of the gene of interest is frequently more pronounced after siRNA transfection compared to shRNA [51]. Screens may be performed as arrays in 96- or 384-well plate formats with one gene being silenced per well. After introduction of the siRNAs, these plates can be evaluated for many cellular features such as viability, apoptosis, motility, transcriptional activation of distinct pathways using luciferase-based read-outs or cell morphology using high-throughput microscopy (Figure 1). Alternatively, screens may also be performed by transfecting or transducing pooled shRNA-plasmids with selection markers. After selecting transfected cells, enrichment or depletion of distinct shRNAs can be analyzed by high-throughput sequencing.

Bottom Line: More than a decade ago, microarray technology was introduced to identify differentially expressed genes in pancreatic cancer as compared to normal pancreas, chronic pancreatitis and other cancer types located in close proximity to the pancreas.In addition, proteomic screens have facilitated the identification of differentially secreted proteins in body fluids of pancreatic cancer patients, serving as possible biomarkers.Recently, RNA interference-based loss-of-function screens have been used to identify functionally relevant genes, whose knock-down has impact on pancreatic cancer cell viability, thereby representing potential new targets for therapeutic intervention.

View Article: PubMed Central - PubMed

Affiliation: Department of Gastroenterology and Endocrinology, University Hospital, Philipps-University Marburg, Baldinger Strasse, D-35043 Marburg, Germany. michlp@med.uni-marburg.de.

ABSTRACT
Pancreatic cancer exhibits an extraordinarily high level of resistance to almost any kind of systemic therapy evaluated in clinical trials so far. Therefore, the identification of novel therapeutic targets is urgently required. High-throughput screens have emerged as an important tool to identify putative targets for diagnosis and therapy in an unbiased manner. More than a decade ago, microarray technology was introduced to identify differentially expressed genes in pancreatic cancer as compared to normal pancreas, chronic pancreatitis and other cancer types located in close proximity to the pancreas. In addition, proteomic screens have facilitated the identification of differentially secreted proteins in body fluids of pancreatic cancer patients, serving as possible biomarkers. Recently, RNA interference-based loss-of-function screens have been used to identify functionally relevant genes, whose knock-down has impact on pancreatic cancer cell viability, thereby representing potential new targets for therapeutic intervention. This review summarizes recent results of transcriptional, proteomic and functional screens in pancreatic cancer and discusses potentials and limitations of the respective technologies as well as their impact on future therapeutic developments.

No MeSH data available.


Related in: MedlinePlus