Probes for INS

Abstract

AIM:

To determine whether it is possible to identify different immune phenotypic subpopulations of cancer-associated fibroblasts (CAFs) in pancreatic cancer (PC).

METHODS:

We defined four different stromal compartments in surgical specimens with PC: The juxtatumoural, peripheral, lobular and septal stroma. Tissue microarrays were produced containing all pre-defined PC compartments, and the expression of 37 fibroblast (FB) and 8 extracellular matrix (ECM) markers was evaluated by immunohistochemistry, immunofluorescence (IF), double-IF, and/or in situ hybridization. The compartment-specific mean labelling score was determined for each marker using a four-tiered scoring system. DOG1 gene expression was examined by quantitative reverse transcription PCR (qPCR).

RESULTS:

CD10, CD271, cytoglobin, DOG1, miR-21, nestin, and tenascin C exhibited significant differences in expression profiles between the juxtatumoural and peripheral compartments. The expression of CD10, cytoglobin, DOG1, nestin, and miR-21 was moderate/strong in juxtatumoural CAFs (j-CAFs) and barely perceptible/weak in peripheral CAFs (p-CAFs). The upregulation of DOG1 gene expression in PC compared to normal pancreas was verified by qPCR. Tenascin C expression was strong in the juxtatumoural ECM and barely perceptible/weak in the peripheral ECM. CD271 expression was barely perceptible in j-CAFs but moderate in the other compartments. Galectin-1 was stronger expressed in j-CAFs vs septal fibroblasts, PDGF-Rβ, tissue transglutaminase 2, and hyaluronic acid were stronger expressed in lobular fibroblasts vs p-CAFs, and plectin-1 was stronger expressed in j-CAFs vs l-FBs. The expression of the remaining 33 markers did not differ significantly when related to the quantity of CAFs/FBs or the amount of ECM in the respective compartments.

CONCLUSION:

Different immune phenotypic CAF subpopulations can be identified in PC, using markers such as cytoglobin, CD271, and miR-21. Future studies should determine whether CAF subpopulations have different functional properties.

Fibroblast growth factor (FGF) signaling is essential for many developmental processes and plays a pivotal role in skeletal homeostasis, regeneration and wound healing. FGF signals through one of five tyrosine kinase receptors: Fgfr1a, -1b, -2, -3, -4. To characterize the expression of zebrafish fgfr3 from the larval stage to adulthood, we used RNAscope in situ hybridization on paraffin sections of the zebrafish head. Our study revealed spatial and temporal distribution of fgfr3 transcript in chondrocytes of the head cartilages, osteoblasts involved in bone formation, ventricular zone of the brain, undifferentiated mesenchymal cells of the skin, and lens epithelium of the eye. In general, the expression pattern of zebrafish fgfr3 is similar to the expression observed in higher vertebrates.

Gastric cancer is the fifth most common cancer and third leading cause of cancer-related death worldwide. Several studies on angiogenic blocking agents in gastric cancer revealing promising results by the use of monoclonal antibodies against VEGFA or its receptor VEGFR2 or against VEGFA activating pathway. The validation of biomarkers useful to better organize the clinical trials involving anti-angiogenic therapies is crucial. Molecular markers such as RNA are increasingly used for cancer diagnosis, prognosis, and therapy guidance as in the case of the targeted therapies concerning the inhibition of angiogenesis. The aim of this study is to set the conditions for evaluating the expression of VEGFA and VEGFR2 in gastric cancer specimens and in healthy gastric mucosa by the use of RNAscope, a novel RNA in situ hybridization (ISH) method that allows the visualization of a specific gene expression in individual cells. We found the increased expression of VEGFA in the tubular glands and VEGFR2 in the endothelium of gastric cancer samples mainly in the T2, T3 and T4 stages of tumor progression as compared to the healthy controls. These results obtained by the application of this highly sensitive method for oligonucleotide detection the role of angiogenesis in gastric cancer progression already highlighted by conventional immunohistochemical methods, and offer significant promise as a new platform for developing and implementing RNA-based molecular diagnostics also in the conditions in which immunohistochemistry is not applicable.

Amplification of vascular endothelial growth factor A (VEGFA) has been recently reported in TFEB-amplified renal cell carcinomas regardless the level of TFEB amplification. We sought to determine VEGFA amplification by fluorescent in situ hybridization (FISH) and VEGFA mRNA expression by in situ hybridization (RNAscope 2.5) in a series of 10 renal cell carcinomas with TFEB gene alterations, either amplification and/or rearrangement (t(6;11) renal cell carcinoma). TFEB gene rearrangement was demonstrated in eight cases, whereas the remaining two cases showed a high level of TFEB (> 10 copies of fluorescent signals) gene amplification without evidence of rearrangement. Among the eight t(6;11) renal cell carcinomas (TFEB-rearranged cases), one case displayed a high level of TFEB gene amplification and two showed increased TFEB gene copy number (3-4 copies of fluorescent signals). Those three cases behaved aggressively. By FISH, VEGFA was amplified in all three cases with TFEB amplification and increased VEGFA gene copy number was observed in the two aggressive cases t(6;11) renal cell carcinomas with an overlapping increased number of TFEB fluorescent signals. Overall, VEGFA mRNA expression was observed in 8 of 10 cases (80%); of these 8 cases, 3 cases showed high-level TFEB amplification, one case showed TFEB rearrangement with increased TFEB gene copy number, whereas four showed TFEB gene rearrangement without increased copy number. In summary, VEGFA amplification/increased gene copy number and VEGFA mRNA expression occur in TFEB-amplified renal cell carcinoma, but also in a subset of t(6;11) renal cell carcinoma demonstrating aggressive behavior, and in unamplified conventional t(6;11) renal cell carcinoma suggesting VEGFA as potential therapeutic target in these neoplasms even in the absence of TFEB amplification. We finally propose that all the renal tumors showing morphological characteristics suggesting t(6;11) renal cell carcinoma and all unclassified renal cell carcinomas, either high grade or low grade, should immunohistochemically be evaluated for cathepsin K and/or Melan-A and if one of them is positive, tested for TFEB gene alteration and VEGFA gene amplification.

Angiostasis mediated by IFNγ is a key mechanism of anti-tumor immunity; however, the effect of IFNγ on host VEGFA-expressing cells during tumor progression is still elusive. Here, we developed transgenic mice with IFNγ receptor (IFNγR) expression under control of the Vegfa promoter (V-γR). In these mice, the IFNγ responsiveness of VEGFA -expressing cells led to a dramatic growth suppression of transplanted lung carcinoma cells. Surprisingly, increased mortality and tumor metastasis were observed in the tumor-bearing V-γR mice, in comparison to the control wild type and IFNγR-deficient mice. Further study showed that perivascular cells were VEGFA-expressing cells and potential IFNγ targets. In vivo, tumor vascular perfusion and pericyte association with blood vessels were massively disrupted in V-γR mice. In vitro, IFNγ inhibited TGF-β-signaling through upregulating SMAD7 and therefore, down-regulated N-cadherin expression in pericytes. Importantly, IFNγ neutralization in vivo using a monoclonal antibody reduced tumor metastasis. Together, the results suggest that IFNγR-mediated dissociation of perivascular cells from blood vessels contributes to the acceleration of tumor metastasis. Thus the inhibition of tumor growth via IFNγ-induced angiostasis might also accelerate tumor metastasis.

The periodontal complex is essential for tooth attachment and function and includes the mineralized tissues, cementum and alveolar bone, separated by the unmineralized periodontal ligament (PDL). To gain insights into factors regulating cementum-PDL and bone-PDL borders and protecting against ectopic calcification within the PDL, we employed a proteomic approach to analyze PDL tissue from progressive ankylosis knock-out (Ank−/−) mice, featuring reduced PPi, rapid cementogenesis, and excessive acellular cementum. Using this approach, we identified the matrix protein osteopontin (Spp1/OPN) as an elevated factor of interest in Ank−/− mouse molar PDL. We studied the role of OPN in dental and periodontal development and function. During tooth development in wild-type (WT) mice, Spp1 mRNA was transiently expressed by cementoblasts and strongly by alveolar bone osteoblasts. Developmental analysis from 14 to 240 days postnatal (dpn) indicated normal histological structures in Spp1−/− comparable to WT control mice. Microcomputed tomography (micro-CT) analysis at 30 and 90 dpn revealed significantly increased volumes and tissue mineral densities of Spp1−/− mouse dentin and alveolar bone, while pulp and PDL volumes were decreased and tissue densities were increased. However, acellular cementum growth was unaltered in Spp1−/− mice. Quantitative PCR of periodontal-derived mRNA failed to identify potential local compensators influencing cementum in Spp1−/− vs. WT mice at 26 dpn. We genetically deleted Spp1 on the Ank−/− mouse background to determine whether increased Spp1/OPN was regulating periodontal tissues when the PDL space is challenged by hypercementosis in Ank−/− mice. Ank−/−; Spp1−/−double deficient mice did not exhibit greater hypercementosis than that in Ank−/− mice. Based on these data, we conclude that OPN has a non-redundant role regulating formation and mineralization of dentin and bone, influences tissue properties of PDL and pulp, but does not control acellular cementum apposition. These findings may inform therapies targeted at controlling soft tissue calcification.