Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis-0

Ucts from normal pancreas in PDAC (Dt), or ducts from non-PDAC (D). Array position is designated using x-y coordinates (A-J, 1–8), and specimens derived from the same case have identical nomenclature (T coordinates/Dt coordinates). Protein distribution is cytoplasmic unless designated as nuclear (N-). Common branches show expression similarities in specimens and proteins using an unsupervised hierarchical clustering analysis. The two largest branches contain specimens of tumor (a) and histologically normal ducts (b).<p><b>Copyright information:</b></p><p>Taken from "Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis"</p><p>http://www.biomedcentral.com/1471-2407/8/43</p><p>BMC Cancer 2008;8():43-43.</p><p>Published online 6 Feb 2008</p><p>PMCID:PMC2270852.</p><p></p

Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis-2

Cimens and proteins from an unsupervised hierarchical clustering analysis.<p><b>Copyright information:</b></p><p>Taken from "Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis"</p><p>http://www.biomedcentral.com/1471-2407/8/43</p><p>BMC Cancer 2008;8():43-43.</p><p>Published online 6 Feb 2008</p><p>PMCID:PMC2270852.</p><p></p

Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis-3

DAC: PKBβ (p = 0.03), nuclear (N-) p-GSK3β (p = 0.008), EGFR (p = 0.055), N-p-ERK (p = 0.04), N-p-p38 (p = 0.03) and p-S6 (p = 0.03). (B) A representative image of centroacinar cells (arrows) and larger ducts (arrowheads) shows positive staining for p-mTOR. (C) A subset of the signaling proteins shows differential staining among the cellular components of the pancreas.<p><b>Copyright information:</b></p><p>Taken from "Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis"</p><p>http://www.biomedcentral.com/1471-2407/8/43</p><p>BMC Cancer 2008;8():43-43.</p><p>Published online 6 Feb 2008</p><p>PMCID:PMC2270852.</p><p></p

Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis-4

Ucts from normal pancreas in PDAC (Dt), or ducts from non-PDAC (D). Array position is designated using x-y coordinates (A-J, 1–8), and specimens derived from the same case have identical nomenclature (T coordinates/Dt coordinates). Protein distribution is cytoplasmic unless designated as nuclear (N-). Common branches show expression similarities in specimens and proteins using an unsupervised hierarchical clustering analysis. The two largest branches contain specimens of tumor (a) and histologically normal ducts (b).<p><b>Copyright information:</b></p><p>Taken from "Immunohistochemical analysis of changes in signaling pathway activation downstream of growth factor receptors in pancreatic duct cell carcinogenesis"</p><p>http://www.biomedcentral.com/1471-2407/8/43</p><p>BMC Cancer 2008;8():43-43.</p><p>Published online 6 Feb 2008</p><p>PMCID:PMC2270852.</p><p></p

Hedgehog inhibition mediates radiation sensitivity in mouse xenograft models of human esophageal adenocarcinoma

<div><p>Background</p><p>The Hedgehog (Hh) signaling pathway is active in esophageal adenocarcinoma (EAC). We used a patient-derived murine xenograft (PDX) model of EAC to evaluate tumour response to conventional treatment with radiation/chemoradiation with or without Hh inhibition. Our goal was to determine the potential radioresistance effects of Hh signaling and radiosensitization by Hh inhibitors.</p><p>Methods</p><p>PDX models were treated with radiation, chemotherapy or combined chemoradiation. Tumour response was measured by growth delay. Hh transcript levels (qRT-PCR) were compared among frozen tumours from treated and control mice. 5E1, a monoclonal SHH antibody, or LDE225, a clinical SMO inhibitor (Novartis®) inhibited Hh signaling.</p><p>Results</p><p>Precision irradiation significantly delayed xenograft tumour growth in all 7 PDX models. Combined chemoradiation further delayed growth relative to either modality alone in three of six PDX models. Following irradiation, two of three PDX models demonstrated sustained up-regulation of Hh transcripts. Combined LDE225 and radiation, and 5E1 alone delayed growth relative to either treatment alone in a Hh-responsive PDX model, but not in a non-responsive model.</p><p>Conclusion</p><p>Hh signaling mediates the radiation response in some EAC PDX models, and inhibition of this pathway may augment the efficacy of radiation in tumours that are Hh dependent.</p></div

Hedgehog inhibition increases growth delay in some PDX models.

<p>Arrows indicate day of irradiation. <b>(A)</b> 5E1 used on a Hh-nonresponsive model. <b>(B)</b> 5E1 used on a Hh-responsive model. <b>(C)</b> LDE225 used on the same Hh-responsive model.</p

Chemoradiation growth delays vary across PDX models.

<p>Arrows indicate time of irradiation. Growth delays that are significant versus chemotherapy alone and versus radiation alone are marked with an asterisk and circle, respectively.</p

Xenograft experimental design.

<p>A radiation experiment is shown as an example. Similar protocols were used for chemoradiation and for hedgehog inhibitor experiments, albeit with larger numbers of mice and without RT-PCR. *Up to 90 mice were used for large hedgehog inhibitor experiments to ensure sufficient numbers remained at the conclusion of the experiment.</p

Baseline expression of Hedgehog transcripts in untreated EAC tumours from six PDX models.

<p>“Human” represents the patient-derived epithelium. “Mouse” represents the host stroma. Transcript levels are normalized to the highest expressed gene per species per model.</p

Radiation up-regulates Hedgehog transcription in some EAC tumours relative to controls.

<p>Significant (p<0.05) fold changes are underlined. Fold changes that are both ≥1.5 and statistically significant are shaded in grey. A lemniscate indicates that transcripts were undetectable in controls but detectable in treated tumours (infinite fold change). N/A indicates undetectable transcripts in treated tumours. (A-C) Fold changes in transcript levels in models 8, 6 and 7.</p