Demystified...tissue microarray technology

Targeting abundant survivin expression in liposarcoma: subtype dependent therapy responses to YM155 treatment

Purpose

Liposarcoma (LPS) represent the largest group of malignant soft tissue tumours comprising a heterogeneous group of subtypes in which the degrees of chemoresistance and radiosensitivity strongly vary. Consequently, it is of utmost interest to establish novel therapeutic regimens based on molecular targets.

Methods

Immunohistochemical staining of survivin was performed in tissue microarrays comprising 49 primary LPS specimens. LPS cell lines were treated with survivin antagonist YM155 and doxorubicin or etoposide alone as well as in combination. Changes in cell viability were investigated and the synergistic effect of a combined therapy analysed.

Results

Immunohistochemistry revealed an abundant expression of survivin in LPS that significantly concurred with less-differentiated tumour subtypes and grading. In vitro, we demonstrated the impact of the survivin inhibitor YM155 on dedifferentiated LPS (DDLPS) and, even more imposing, pleomorphic LPS (PLS) tumour cell viability with a strong induction of apoptosis. A combined treatment of doxorubicin or etoposide with YM155 augmented the cytotoxic effects on DDLPS and PLS cells.

Conclusion

These findings support the significant role of survivin in the oncogenesis and progression of LPS subtypes providing a rationale to target survivin in eligible in-vivo models and to pioneer clinical applications of survivin-specific substances unfolding their therapeutic potential in LPS patients prospectively.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03871-5.

Tissue microarrays - brief history, techniques and clinical future

Introduction and Aim: There is a growing need for better, cheaper and faster histopathological diagnostic. The authors reviewed the main steps of the efforts towards the improvement of the pre-analytical phase of tissue processing for histological examination. Results: Since their introduction decades ago tissue microarrays (TMAs) proved their value by increasing efficiency, standardization and accuracy of many histological techniques, such as histochemistry, histoenzymology, immunohistochemistry, in situ hybridization, etc. By allowing the simultaneous analysis and comparison of multiple different tissues on a single histology slide (up to 1000 individual samples), TMAs are also having a significant economic advantage (consumables and labor). From its first description until recent years, the TMA techniques have evolved steadily but slowly despite many attempts to adapt it for clinical diagnostics. In this paper, we are reviewing the main techniques of obtaining TMA blocks from the beginning to the present day, as well as recent developments that are expanding their scope into high accuracy/efficiency clinical diagnostics. Conclusions: Considering recent developments, we believe that the prospect of high-throughput histology might be achievable in the not-so-distant future.

Preparation, construction and high-throughput automated analysis of human brain tissue microarrays for neurodegenerative disease drug development

A major challenge in the treatment of neurodegenerative disorders is the translation of effective therapies from the lab to the clinic. One approach to improve this process is the use of human brain tissue microarray (HBTMA) technology to aid in the discovery and validation of drug targets for brain disorders. In this protocol we describe a platform for the production of high-quality HBTMAs that can be used for drug target discovery and validation. We provide examples of the use of this platform and describe detailed protocols for HBTMA design, construction and use for both protein and mRNA detection. This platform requires less tissue and reagents than single-slide approaches, greatly increasing throughput and capacity, enabling samples to be compared in a more consistent way. It takes 4 d to construct a 60 core HBTMA. Immunohistochemistry and in situ hybridization take a further 2 d. Imaging of each HBTMA slide takes 15 min, with subsequent high-content analysis taking 30 min-2 h.

Establishment of an Academic Tissue Microarray Platform as a Tool for Soft Tissue Sarcoma Research

Soft tissue sarcoma (STS) is a heterogeneous family of rare mesenchymal tumors, characterized by histopathological and molecular diversity. Tissue microarray (TMA) is a tool that allows performing research in orphan diseases in a more efficient and cost-effective way. TMAs are paraffin blocks consisting of multiple small representative tissue cores from biological samples, for example, from multiple donors, diverse sites of disease, or multiple different diseases. In 2015, we began constructing TMAs using archival tumor material from STS patients. Specimens were well annotated in terms of histopathological diagnosis, treatment, and clinical follow-up of the tissue donors. Each TMA block contains duplicate or triplicate 1.0–1.5 mm tissue cores from representative tumor areas selected by sarcoma pathologists. The construction of TMAs was performed with TMA Grand Master (3DHistech). So far, we have established disease-specific TMAs from 7 STS subtypes: gastrointestinal stromal tumor (72 cases included in the array), alveolar soft part sarcoma (n = 12 + 47), clear cell sarcoma (n = 22 + 32), leiomyosarcoma (n = 55), liposarcoma (n = 42), inflammatory myofibroblastic tumor (n = 12 + 21), and alveolar rhabdomyosarcoma (n = 24). We also constructed a multisarcoma TMA covering a representative number of important histopathological subtypes on arrays for screening purposes, namely, angiosarcoma, dedifferentiated liposarcoma, pleomorphic liposarcoma, and myxoid liposarcoma, leiomyosarcoma, malignant peripheral nerve sheath tumor, myxofibrosarcoma, rhabdomyosarcoma, synovial sarcoma, and undifferentiated pleomorphic sarcoma, with 7–11 individual cases per subtype. We are currently expanding the list of TMAs with additional sarcoma entities, considering the heterogeneity of this family of tumors. Our extensive STS TMA platform is suitable for rapid and cost-effective morphological, immunohistochemical, and molecular characterization of the tumor as well as for the identification of potential novel diagnostic markers and drug targets. It is readily available for collaborative projects with research partners.

Recommendations for Tissue Microarray Construction and Quality Assurance

Tissue microarrays (TMAs) are important tools to conserve precious tissue resources from increasingly smaller biopsies and to control experimental costs and variation across sample sets. The quality assurance assessment of TMA materials created at centralized biobanks has not been standardized. Herein, we outline 2 processes for the construction of TMAs ("recipient block" and "tape" methods) and the associated preconstruction quality control measures (pathology review, protein and RNA assessment, map creation, and storage conditions) developed by the AIDS Cancer Specimen Resource (ACSR) Network's Science and Technology Core. These steps provide a suggested framework for quality assessment that allows end-users, receiving materials from tissue banks, confidence in their experimental results.

Site-specific gene expression patterns in oral cancer

BACKGROUND

Squamous cell carcinomas (SCCs) are the most prevalent malignant tumours within the head and neck. Evidence exists that distinct genes are differentially regulated in SCCs of the oral cavity compared to other head and neck regions. Given this background, the aim of this study was to investigate whether such tumour site-specific gene expression can also be observed in different localizations within the oral cavity.

METHODS

Using tissue microarrays (TMAs), we investigated 76 SCCs of the floor of the mouth, 49 SCCs of the tongue and 68 SCCs of other anatomic regions within the oral cavity. The expression of 17 genes involved in cell cycle and growth control (p16, p21, p27, p53, cyclin D1, EGFR, c-kit, bcl-6), cell adhesion (alpha-, beta-, and gamma-catenin), and apoptosis/stress response genes (Hif-1-alpha, Glut 1, CA IX, caspase, hsp70, XIAP) were investigated by means of immunohistochemistry. The data were subjected to chi², interdependency and Kaplan-Meier analysis.

RESULTS

Our study suggests a remote difference in the site-specific gene expression patterns of oral cancer. X-linked inhibitor of apoptosis (XIAP) showed a significantly higher expression (p <0.05) in SCCs of the floor of the mouth compared to SCCs of the tongue and other locations within the oral cavity. The increased XIAP expression was further associated with significantly decreased overall survival in all cases of SCCs of the oral cavity (p <0.05). Expression levels of p53, CA IX, beta-catenin, Hif-1-alpha, and c-kit were also observed to be inversely related between SCCs of the floor of the mouth and those of the tongue respectively, although these differences did not reach statistical significance. Overall and event-free survival did not differ in patients with T1/T2/N0 SCCs according to tumour localization.

CONCLUSION

In summary, the protein expression patterns of SCCs of the oral cavity suggest the existence of a molecular and morphological spectrum of SCCs in the oral cavity. In particular the expression pattern of XIAP indicates distinct gene expression patterns between carcinomas of the floor of the mouth and oral tongue cancer. Further studies are needed to identify possible tumour site-specific factors that influence patient prognosis and management.

Cytokeratin and protein expression patterns in squamous cell carcinoma of the oral cavity provide evidence for two distinct pathogenetic pathways

Squamous cell carcinoma (SCC) of the oral cavity is a morphological heterogeneous disease. Various cytokeratin (CK) expression patterns with different prognostic values have been described, but little is known concerning the underlying biological cell mechanisms. Therefore, the present study investigated 193 cases of oral SCCs using immunohistochemistry for α/β/γ-catenin, glucose transporter 1, caspase-3, X-linked inhibitor of apoptosis protein, hypoxia inducible factor-1α, carbonic anhydrase 9, heat shock protein (hsp) 70, mast/stem cell growth factor receptor, p21, p27, p16, p53, B-cell lymphoma 6, epidermal growth factor receptor, cyclin D1 and CK1, 5/6, 8/18, 10, 14 and 19. Expression patterns were analyzed with biomathematical permutation analysis. The present results revealed a significant association between the expression of low-molecular weight CK8/18 and 19 and a high-tumor grade, β and γ-catenin expression, deregulated cell cycle proteins and a predominant localization of the tumor on the floor of the mouth. By contrast, expression of high-molecular weight CK1, 5/6, 10 and 14 was significantly associated with the expression of p21 and hsp70. In conclusion, the current study presents evidence for the existence of two parallel pathogenetic pathways in oral SCCs, characterized by the expression of low- and high-molecular weight CKs. Additional studies are required to demonstrate the extent that these results may be used to improve therapeutic regimens.

Ki67--An unsuitable marker of gastric cancer prognosis unmasks intratumoral heterogeneity

Background and Objectives

Due to contradictious findings of previous studies regarding Ki67's value in gastric cancer (GC), we reevaluated the expression of Ki67 in whole tissue sections (WTS) and tissue microarrays (TMAs) of GC testing the following hypotheses: does Ki67 show intratumoral heterogeneity; are TMAs representative in the determination of the Ki67 proliferation index (PI); is the Ki67 PI subject to an intralaboratory variability; and is the Ki67 PI related to clinico‐pathological patient characteristics and/or prognostically relevant in GC.

Methods

Corresponding WTS and TMAs samples from 315 GCs were stained immunohistochemically. The Ki67 PI evaluated on WTS was correlated with the Ki67 PI evaluated on TMAs, sample age, clinico‐pathological characteristics, and patient survival.

Results

The overall amount of Ki67‐positive tumor cells did not depend on sample age. Three distinct, partly heterogeneous Ki67 expression patterns were observed. The mean Ki67 PI evaluated on TMAs differed on average minus 16.9% from the Ki67 PI evaluated on WTS. Ki67 in WTS correlated significantly with the Laurén phenotype and tumor grade, but not with patient survival.

Conclusion

TMAs carry the risk of a systematic underestimation of the Ki67 PI. Ki67 has no prognostic value in GC but might be a potential indicator of intratumoral heterogeneity. J. Surg. Oncol. 2016;113:46–54. © 2015 The Authors. Journal of Surgical Oncology published by Wiley Periodicals, Inc.

Integrins αvβ3 and αvβ5 as prognostic, diagnostic, and therapeutic targets in gastric cancer

BACKGROUND

We investigated the expression of two αv integrins, αvβ3 and αvβ5, in gastric cancer (GC) by testing the following hypotheses: that these molecules are expressed in GC; that they are implicated in GC biology; that they help to distinguish between the two major histological subtypes of GC, according to Laurén; and that they are prognostically relevant.

METHODS

Formalin-fixed and paraffin-embedded tissue samples from 482 GC samples were stained immunohistochemically using rabbit monoclonal antibodies directed against αvβ3 (EM22703) and αvβ5 (EM09902). Immunostaining of tumor, stroma, and endothelial cells was evaluated separately by the quantity and intensity, generating an immunoreactivity score. The immunoreactivity score of both antibodies was correlated with clinicopathology data and patient survival.

RESULTS

Each integrin was expressed in at least one tumor component in all GCs. Both were expressed significantly more often in the intestinal phenotype according to Laurén. Moreover, patients who grouped as "positive" for expression of αvβ3 on endothelial cells, and patients with an intestinal type GC, grouped as "negative" for expression of αvβ5 on stroma cells, had significantly longer survival. The expression of αvβ5 on stroma cells was confirmed to be an independent prognostic factor of intestinal-type GC.

CONCLUSION

The expression of αvβ3 and αvβ5 in at least one tumor component in all GC samples is an interesting new result that should form a basis for further investigations; for example, regarding selective integrin antagonists and the value of αvβ3 and αvβ5 as putative prognostic biomarkers. Moreover, both markers might be helpful in the routine classification of GC subtypes.

The use of tissue microarrays for semiquantitative evaluation of ATPaseC1 expression is ineffective

We described earlier the possible role of ATPaseC1 expression as a diagnostic and prognostic marker for oral cancer; others have reported its use for tumors of the lung and breast. We assessed ATPaseC1 expression in a sample of oral squamous cell carcinoma (OSCC) using tissue microarrays (TMAs) to analyze the relation between ATPaseC1 expression and clinical, histopathological and prognostic parameters. We performed a retrospective study of 48 cases of OSCC. We constructed TMAs using two different regions of each tumor. V-ATPaseC1 immunohistochemistry was performed and assessed semiquantitatively. ATPaseC1 staining was observed in most of the neoplastic cells in all tumors. Staining was diffusely cytoplasmic and, to a lesser extent, nuclear. The degree of concordance between the measurements performed in tissue microarray 1 (TMA1) and tissue microarray 2 (TMA2), as evaluated using the intra-class correlation coefficient (ICC), was low. We found great variability in the immunohistochemical staining of the different regions of each tumor. We found 16 cases with mild expression (33.3%), 20 with moderate expression (41.7%) and 12 with intense expression (25%). Differences in the clinical-pathological variables studied were not statistically significant. The difficulty of immunohistochemical evaluation, the heterogeneity of the carcinomas and the fact that evaluation of expression requires semiquantitative analysis render the reliability of the results obtained from TMA-based techniques questionable.

Mitochondrial dynamics protein Drp1 is overexpressed in oncocytic thyroid tumors and regulates cancer cell migration

Oncocytic cell tumors are characterized by the accumulation of morphologically abnormal mitochondria in their cells, suggesting a role for abnormal mitochondrial biogenesis in oncocytic cell transformation. Little is known about the reason for the dysmorphology of accumulated mitochondria. The proteins regulating the morphology of mitochondria, the "mitochondria-shaping" proteins, can modulate their size and number; however, nothing is known hitherto about a possible involvement of mitochondrial dynamics in oncocytic cell transformation in tumors. Our aim was to assess the status of the mitochondria morphology and its role in oncocytic cell transformation. We therefore evaluated the expression pattern of the main mitochondrial fusion and fission proteins in a series of thyroid cell tumor samples, as well as in thyroid tumor cell lines, with and without oncocytic cell features. The expression of mitochondrial fusion (Opa1, Mfn1 and Mfn2) and fission (Drp1 and Fis1) proteins were evaluated by immunohistochemistry (IHC) in a series of 88 human thyroid tumors. In vitro studies, for comparative purposes and to deepen the study, were performed using TPC1 - a papillary thyroid carcinoma derived cell line—and XTC.UC1, an oncocytic follicular thyroid carcinoma-derived cell line. Both IHC and in vitro protein analyses showed an overall increase in the levels of "mitochondrial-shaping" proteins in oncocytic thyroid tumors. Furthermore, overexpression of the pro-fission protein Drp1 was found to be associated with malignant oncocytic thyroid tumors. Interestingly, genetic and pharmacological blockage of Drp1 activity was able to influence thyroid cancer cells’ migration/invasion ability, a feature of tumor malignancy. In this study we show that unbalanced mitochondrial dynamics characterize the malignant features of thyroid oncocytic cell tumors, and participate in the acquisition of the migrating phenotype.

Immunoexpression of cyclin D1 in colorectal carcinomas is not correlated with survival outcome

Background

Colon and colorectal cancer (CRC) research has entered a new era with recent updates of molecular events and prognostic markers. Among other prognostic markers, exaggerated expression of nuclear CCND1 has key role in tumour pathogenesis and metastases of CRC and has also been claimed to predict response to treatment.

Objectives

This study was designed to evaluate the prognostic and predictive value of CCND1 in CRC and the correlation of CCND1 expression with the different clinicopathological parameters.

Methods

Paraffin blocks from 117 primary CRC were retrieved from the archives of the Department of Pathology at King Abdulaziz University. Tissue microarrays were designed and constructed. The immunostaining of CCND1 was performed and analysed.

Results

There were more cases with low nuclear immunoexpression of CCND1 in both primary tumours and nodal metastasis (p <0.001). Cyclin D1 did not show association with clinicopathological features except with lymphovascular invasion. Low nuclear immunoexpression of CCND1 was associated with negative lymphovascular invasion (p = 0.046). There was no statistically significant correlation between CCND1 immunoexpression and survival probability (Log Rank = 2.474, p = 0.116).

Conclusion

Our study indicates that CCND1 immunoexpression cannot be used as a predictor of survival in CRC. It also shows no significant correlation with clinicopathological features except with lymphovascular invasion.

MicroRNA-181a promotes tumor growth and liver metastasis in colorectal cancer by targeting the tumor suppressor WIF-1

Background

Given the emerging role of microRNA in tumor disease progression, we investigated the association between microRNA expression, liver metastasis and prognosis of colorectal cancer.

Methods

Colorectal cancer tissues from patients with or without liver metastases were profiled to identify differentially expressed microRNA. Expression profile was further assessed using quantitative reverse transcription PCR and in situ hybridization. Correlation between miR-181a expression, the most differentially expressed microRNA, between patients with and without liver metastasis, and its downstream target genes were investigated using qRT-PCR. Luciferase reporter assay was conducted to establish functional association between miR-181a and its target genes. Manipulation of miR-181a expression and its consequences in tumor growth and metastasis were demonstrated in various in vitro and in vivo models.

Results

miR-181a was revealed being the most elevated in CRC with liver metastases. miR-181a expression correlated with advanced stage, distant metastasis, and served as an independent prognostic factor of poor overall survival. Stable transfection of CRC cell lines with miR-181a promoted cell motility and invasion, as well as tumor growth and liver metastasis,while silencing its expression resulted in reduced migration and invasion. Additionally, we identified WIF-1 as direct and functional targets of miR-181a. Ectopic expression of miR-181a suppressed the epithelial markers E-cadherin and β-catenin, while enhanced the mesenchymal markers vimentin.

Conclusion

Our data demonstrate that miR-181a expression is associated with CRC liver metastasis and survival. miR-181a has strong tumor-promoting effects through inhibiting the expression of WIF-1, and its potential role in promoting epithelial-mesenchymal transition.

Overview on Techniques to Construct Tissue Arrays with Special Emphasis on Tissue Microarrays

With the advent of new histopathological staining techniques (histochemistry, immunohistochemistry, in situ hybridization) and the discovery of thousands of new genes, mRNA, and proteins by molecular biology, the need grew for a technique to compare many different cells or tissues on one slide in a cost effective manner and with the possibility to easily track the identity of each specimen: the tissue array (TA). Basically, a TA consists of at least two different specimens per slide. TAs differ in the kind of specimens, the number of specimens installed, the dimension of the specimens, the arrangement of the specimens, the embedding medium, the technique to prepare the specimens to be installed, and the technique to construct the TA itself. A TA can be constructed by arranging the tissue specimens in a mold and subsequently pouring the mold with the embedding medium of choice. In contrast, preformed so-called recipient blocks consisting of the embedding medium of choice have punched, drilled, or poured holes of different diameters and distances in which the cells or tissue biopsies will be deployed manually, semi-automatically, or automatically. The costs of constructing a TA differ from a few to thousands of Euros depending on the technique/equipment used. Remarkably high quality TAs can be also achieved by low cost techniques.

Identification of New Players in Hepatocarcinogenesis: Limits and Opportunities of Using Tissue Microarray (TMA)

Liver tumours are among the leading causes of cancer-related death worldwide and hepatocellular carcinoma (HCC) accounts for the vast majority of liver tumours. When detected at an early stage of disease, patients might still be eligible for surgical-based curative treatments. However, currently only small portion of HCC affected patients are diagnosed at an early stage. For late stage HCC no treatment option exists beside the multi-tyrosine kinase inhibitor Sorafenib. Thus new molecular targets and treatment options for HCC are urgently needed. Nevertheless, despite some improvements in diagnosis and patient management, the biology of liver tumour remains inadequately understood, mainly because these tumours have shown to harbour a highly complex genomic landscape. In addition, one major obstacle delaying the identification of new molecular targets in biomedical research is the necessity to validate them using a large collection of tissue specimens. Tissue microarray (TMA) technology allows the prompt molecular profiling of multiple tissue specimens and is therefore ideal to analyze presumptive candidate biomarkers in a fast an effective manner. The use of TMA has substantial benefits over standard techniques and represents a significant advancement in molecular pathology. For example, TMA technology reduces laboratory work, offers a high level of experimental uniformity and provides a judicious use of precious tissue. On the other hand, one potential limitation of using TMA is that the small cores sampled may not be representative of whole tumors. This issue is very critical in particularly heterogeneous cancers such as HCC. For liver focused studies, it is ideal to evaluate the staining patters of a determined marker over the structure of an entire acinus and to define staining in as many as possible anatomical regions. In this review we analyze the limits and opportunities offered by the usage of TMA technology in HCC research. In summary, TMA has revolutionized the histopathological analysis and will be of great help to further advance the knowledge in the field of hepatocarcinogenesis research.

A 'waterfall' transfer-based workflow for improved quality of tissue microarray construction and processing in breast cancer research

A major focus in cancer research is the identification of biomarkers for early diagnosis, therapy prediction and prognosis. Hereby, validation of target proteins on clinical samples is of high importance. Tissue microarrays (TMAs) represent an essential advancement for high-throughput analysis by assembling large numbers of tissue cores with high efficacy and comparability. However, limitations along TMA construction and processing exist. In our presented study, we had to overcome several obstacles in the construction and processing of high-density breast cancer TMAs to ensure good quality sections for further research. Exemplarily, 406 breast tissue cores from formalin-fixed and paraffin embedded samples of 245 patients were placed onto three recipient paraffin blocks. Sectioning was performed using a rotary microtome with a "waterfall" automated transfer system. Sections were stained by immunohistochemistry and immunofluorescence for nine proteins. The number and quality of cores after sectioning and staining was counted manually for each marker. In total, 97.1 % of all cores were available after sectioning, while further 96 % of the remaining cores were evaluable after staining. Thereby, normal tissue cores were more often lost compared to tumor tissue cores. Our workflow provides a robust method for manufacturing high-density breast cancer TMAs for subsequent IHC or IF staining without significant sample loss.

Tissue microarrays: fast-tracking protein expression at the cellular level

Tissue microarrays maximize returns in cellular pathology whilst minimizing the use of cells and tissues. They are made by arraying cores of tissue taken from multiple donor blocks into a single recipient block. Accordingly, the histology and pathology of several hundred tissues can be represented in one tissue microarray that, when stained by immunohistochemistry, provides comprehensive topographic information on protein expression. Used with complimentary techniques, such as complementary DNA microarray analysis, tissue microarrays are providing valuable data for the identification of new markers of disease and assisting in the discovery of therapeutic targets. They are also leading a revolution in cellular pathology as high-throughput technology is introduced to maximize the information provided.

Nuclear localization of the transcriptional coactivator YAP is associated with invasive lobular breast cancer

Background

Yes Associated Protein (YAP) has been implicated in the control of organ size by regulating cell proliferation and survival. YAP is a transcriptional coactivator that controls cellular responses through interaction with TEAD transcription factors in the nucleus, while its transcriptional functions are inhibited by phosphorylation-dependent translocation to the cytosol. YAP overexpression has been associated with different types of cancer, such as lung, skin, prostate, ovary and liver cancer. Recently, YAP was linked to E-cadherin-dependent regulation of contact inhibition in breast cancer cells.

Results

In this study we examined YAP protein expression and cellular localization in 237 cases of human invasive breast cancer by immunohistochemistry and related its expression to clinicopathological features and E-cadherin expression. We observed that invasive lobular carcinoma is characterized by higher expression levels of both nuclear and cytosolic YAP (p < 0.001). Nuclear YAP expression did not associate with other variables such as lymph node involvement, tumor grade, tumor size, mitotic activity or the molecular sub-types of invasive breast cancer. We observed that high nuclear and cytosolic YAP expression are associated with the E-cadherin deficient breast cancer subtype ILC (p < 0.001) and cell lines derived from human breast cancers and conditional mouse models of human lobular breast cancer.

Conclusions

Since our data indicate that nuclear YAP localization is more common in breast cancers lacking functional adherens junctions, it suggests that YAP-mediated transcription may be involved in the development and progression of invasive lobular breast cancer.

Electronic supplementary material

The online version of this article (doi:10.1007/s13402-013-0143-7) contains supplementary material, which is available to authorized users.

Developments in the immunophenotypic analysis of haematological malignancies

Immunophenotyping is the method by which antibodies are used to detect cellular antigens in clinical samples. Although the major role is in the diagnosis and classification of haematological malignancies, applications have expanded over the past decade. Immunophenotyping is now used extensively for disease staging and monitoring, to detect surrogate markers of genetic aberrations, to identify potential immuno-therapeutic targets and to aid prognostic prediction. This expansion in applications has resulted from developments in antibodies, methodology, automation and data handling. In this review we describe recent advances in both the technology and applications for the analysis of haematological malignancies. We highlight the importance of the expanding repertoire of testing capability for diagnostic, prognostic and therapeutic applications. The impact and significance of immunophenotyping in the assessment of haematological neoplasms are evident.

CXCR4 expression predicts early liver recurrence and poor survival after resection of pancreatic adenocarcinoma

OBJECTIVES

Liver metastasis develops in 60% of patients after resection of pancreatic adenocarcinoma (PAC) and carries a dismal prognosis, but factors predictive of liver recurrence are poorly understood. Experimental evidence suggests that liver metastasis of PAC is mediated by CXCL12/CXCR4 signaling and can be inhibited by CXCR4 antagonist. We aimed to verify whether CXCR4 expression predicts early liver recurrence and poor survival after resection, and to explore the usefulness of CXCR4 status for prognosis prediction.

METHODS

Ninety-seven consecutive PAC patients undergoing R0 resection were analyzed. CXCR4 expression was analyzed by immunohistochemistry, and its associations with liver recurrence-free survival and overall survival were analyzed by Kaplan-Meier estimates and multivariable Cox and accelerated failure time regression models.

RESULTS

CXCR4-positive patients had a worse prognosis than CXCR4-negative patients, with a shorter liver recurrence-free survival (median: 8.7 vs. 39.7 months; P=0.004) and overall survival (median: 10.2 vs. 22.3 months; P<0.001). Overall survival for CXCR4-positive stage IIa patients was similar to that for stage IIb patients and significantly shorter than that for CXCR4-negative stage IIa patients (median: 9.7 vs. 27.4 months; P=0.002). CXCR4 positivity was significantly associated with liver recurrence (adjusted hazard ratio 2.22, 95% confidence interval (CI) 1.15-4.30; P=0.018) and predicted a 46% (95% CI 9-68%) and 35% (95% CI 7-54%) reduction in liver recurrence-free survival and overall survival, respectively.

CONCLUSIONS

Tumor CXCR4 expression independently predicts early liver recurrence and poor overall survival after resection of PAC. CXCR4 status stratifies stage IIa patients into two groups with a striking difference in prognosis.

Is there 'progression through grade' in ductal invasive breast cancer?

Recent molecular data pointed towards the possibility of a stepwise dedifferentiation in a subgroup of invasive breast cancer (BC) cases. It was hypothesized that oestrogen receptor positive (ER+) grade 3 (G3) ductal invasive BCs are the end stage of a dedifferentiation process of luminal BC. A progression of luminal A towards luminal B BCs associated with a 'progression through grade' and an increased cell proliferation seemed the obvious explanation. In order to verify this hypothesis on a morphological and immunohistochemical level, we investigated 865 invasive BC cases. All cases were reviewed for the presence of intratumoural heterogeneity in grade of the invasive cancer and the presence of associated ductal carcinoma in situ (DCIS). With the use of tissue microarrays, the molecular subtype was determined and correlated with clinico-pathological features. In addition, all cases were stained for p21, p27, Ki-67, Cyclin D1, bcl-2, p53, and p16 and the results subjected to a biomathematical dependency analysis. The frequency of ER-positivity decreased with tumour size. The frequency of luminal A BC decreased as well, whereas the number of luminal B BCs remained constant. A gradual increase of the frequency of basal-like, HER2-driven and non-expressor BCs with tumour size was seen. In only 1 out of 865 BC cases, both a G1 and a G3 invasive cancer component was seen within the same BC. In two cases, a ductal invasive G1 carcinoma was associated with a poorly-differentiated DCIS. The frequency of columnar cell lesions was evenly distributed over ER+ and ER- ductal invasive G3 carcinomas. The biomathematical analysis gave striking hints against an obligate progression of BC trough grade. In conclusion, our results show that a morphological recognizable striking 'progression through grade' at least in its extreme form from G1 towards G3 is a very rare event in the natural course of invasive BC, including luminal BC.

Immunophenotyping invasive breast cancer: paving the road for molecular imaging

Background

Mammographic population screening in The Netherlands has increased the number of breast cancer patients with small and non-palpable breast tumors. Nevertheless, mammography is not ultimately sensitive and specific for distinct subtypes. Molecular imaging with targeted tracers might increase specificity and sensitivity of detection. Because development of new tracers is labor-intensive and costly, we searched for the smallest panel of tumor membrane markers that would allow detection of the wide spectrum of invasive breast cancers.

Methods

Tissue microarrays containing 483 invasive breast cancers were stained by immunohistochemistry for a selected set of membrane proteins known to be expressed in breast cancer.

Results

The combination of highly tumor-specific markers glucose transporter 1 (GLUT1), epidermal growth factor receptor (EGFR), insulin-like growth factor-1 receptor (IGF1-R), human epidermal growth factor receptor 2 (HER2), hepatocyte growth factor receptor (MET), and carbonic anhydrase 9 (CAIX) 'detected' 45.5% of tumors, especially basal/triple negative and HER2-driven ductal cancers. Addition of markers with a 2-fold tumor-to-normal ratio increased the detection rate to 98%. Including only markers with >3 fold tumor-to-normal ratio (CD44v6) resulted in an 80% detection rate. The detection rate of the panel containing both tumor-specific and less tumor-specific markers was not dependent on age, tumor grade, tumor size, or lymph node status.

Conclusions

In search of the minimal panel of targeted probes needed for the highest possible detection rate, we showed that 80% of all breast cancers express at least one of a panel of membrane markers (CD44v6, GLUT1, EGFR, HER2, and IGF1-R) that may therefore be suitable for molecular imaging strategies. This study thereby serves as a starting point for further development of a set of antibody-based optical tracers with a high breast cancer detection rate.

A review of controversies in the management of soft tissue sarcomas

Soft tissue sarcomas (STS) constitute a rare and challenging group of solid tumor in the field of oncology. Unlike other malignancies STS can affect a wide variety of anatomical regions in the body with varied histo-pathological variants and clinical outcomes. There are controversies in the diagnosis and management of STS due to rarity and heterogeneity of the disease entity. Due to dedicated research and advances made in the field of imaging, pathology, surgery, radiotherapy and chemotherapy certain controversies were laid to rest and treatment approach to STS could be standardized to a large extent in the recent past. A review of controversies related to STS was performed in this article and an attempt was made to present a balanced view pertaining to these issues.

Nuclear Kaiso expression is associated with high grade and triple-negative invasive breast cancer

Kaiso is a BTB/POZ transcription factor that is ubiquitously expressed in multiple cell types and functions as a transcriptional repressor and activator. Little is known about Kaiso expression and localization in breast cancer. Here, we have related pathological features and molecular subtypes to Kaiso expression in 477 cases of human invasive breast cancer. Nuclear Kaiso was predominantly found in invasive ductal carcinoma (IDC) (p = 0.007), while cytoplasmic Kaiso expression was linked to invasive lobular carcinoma (ILC) (p = 0.006). Although cytoplasmic Kaiso did not correlate to clinicopathological features, we found a significant correlation between nuclear Kaiso, high histological grade (p = 0.023), ERα negativity (p = 0.001), and the HER2-driven and basal/triple-negative breast cancers (p = 0.018). Interestingly, nuclear Kaiso was also abundant in BRCA1-associated breast cancer (p<0.001) and invasive breast cancer overexpressing EGFR (p = 0.019). We observed a correlation between nuclear Kaiso and membrane-localized E-cadherin and p120-catenin (p120) (p<0.01). In contrast, cytoplasmic p120 strongly correlated with loss of E-cadherin and low nuclear Kaiso (p = 0.005). We could confirm these findings in human ILC cells and cell lines derived from conditional mouse models of ILC. Moreover, we present functional data that substantiate a mechanism whereby E-cadherin controls p120-mediated relief of Kaiso-dependent gene repression. In conclusion, our data indicate that nuclear Kaiso is common in clinically aggressive ductal breast cancer, while cytoplasmic Kaiso and a p120-mediated relief of Kaiso-dependent transcriptional repression characterize ILC.

Prognostic factors and staging for soft tissue sarcomas: an update

Soft tissue sarcoma (STS) staging is a constantly evolving process. Grading is still of utmost importance and has been adapted into a three-tier system. The STS most difficult to categorize are those with uncertain malignant potential, such as solitary fibrous tumors, gastrointestinal stromal tumors, and glomus tumors, some of which have developed completely separate staging systems and may not even be considered sarcomas. Beyond the current TNM staging system, a multitude of prognostic factors for STS will continue to be discovered and ultimately incorporated into future revisions of the staging system.

A tissue microarray study of osteosarcoma: histopathologic and immunohistochemical validation of xenotransplanted tumors as preclinical models

BACKGROUND

Osteosarcomas (OS) are aggressive neoplasms with a wide range of morphologic patterns.

MATERIALS AND METHODS

OS cases (primary and xenotransplanted) with paraffin blocks available were collected and included in tissue microarrays (TMAs). A morphologic evaluation including the different passages in mice was carried out according to the new WHO criteria. In addition, TMAs were analyzed with a wide panel of immunohistochemical (IHC) markers (osteonectin, osteocalcin,cytokeratin, S100, Sox-9, Ki-67, Bcl-2, p53, p16, survivin, CD99, and caveolin-1).

RESULTS

A total of 61 cases were collected. The distribution of the cases according to the histopathologic pattern was: 38 osteogenic OS, 8 primary chondrogenic OS, 2 primary telangiectatic OS, 6 parosteal OS, 2 primary small cell OS, 2 primary poorly differentiated OS, 1 primary dedifferentiated OS, and 3 primary pleomorphic MFH-like OS. The tumor morphology in xenotransplants was similar to the primary or metastatic tumor of origin and was generally maintained over the passages. The IHC results were heterogeneous and osteonectin and osteocalcin were the most expressed in original tumor and xenografts. S100 and Sox-9 were expressed in chondrogenic areas. Caveolin and survivin showed significant IHC variation between the subsequent passages. p16 displayed heterogenic expression. p53 expression increased over the passages, and Ki-67 expression was not associated with a more undifferentiated pattern, but increased over the passages.

CONCLUSIONS

An accurate morphologic evaluation using TMAs in original tumor is essential for the OS diagnosis; hence there is no IHC marker that alone distinguishes the OS subtypes. Xenografts in OS allow the study of tumor progression in this type of aggressive neoplasm.

Minichromosome maintenance (MCM) and AgNOR proteins expression in desmoid tumours: a tissue microarray analysis

In the present study, nuclear proliferative proteins: MCM2, MCM5, MCM7, Ki-67 and AgNORs expression was assessed in paraffin sections from sporadic desmoid tumours using a tissue microarray (TMA)-based immuno- and histochemistry, respectively. Nuclear expression of MCM7, where the percentage of positive cells was 0.87% (± 1.64) (range 0-5%), was found in 4/20 (20.0%) cases. In 32/32 (100%) of the examined desmoid cases no expression of nuclear proteins MCM2 and MCM5 was detected. Nuclear expression of Ki-67 was observed in 4/21 (19%) cases. Paraffin sections from 30 cases of desmoid tumours were silver-stained to visualize AgNORs. The following AgNOR parameters were calculated: mean AgNOR number per nucleus (N), mean AgNOR area per nucleus, mean AgNOR dot area per nucleus (A), and mean AgNOR content (C = N/A). In the investigated group the mean values of AgNOR parameters were the following number: 4.34 (± 0.11); area: 0.74 μm2 (± 0.19); dot area: 0.18 m2 (± 0.01), and AgNOR content: 23.73 (± 1.85). The mean AgNOR number per nucleus and mean AgNOR content in desmoid tumours were statistically significantly higher as compared to the controls (tonsil tissue) (p<0.001). This study observed low level of MCM7 and Ki-67 and lack of MCM2, MCM5 proteins expression which may explain commonly known low mitotic activity of desmoid tumour cells. The morphology of dots related to AgNORs (number, area) and their morphometric parameters point to elevated transcriptional activity of desmoid cells.

Design, construction, and analysis of cell line arrays and tissue microarrays for gene expression analysis

Cell line array (CMA) and tissue microarray (TMA) technologies are high-throughput methods for analysing both the abundance and distribution of gene expression in a panel of cell lines or multiple tissue specimens in an efficient and cost-effective manner. The process is based on Kononen's method of extracting a cylindrical core of paraffin-embedded donor tissue and inserting it into a recipient paraffin block. Donor tissue from surgically resected paraffin-embedded tissue blocks, frozen needle biopsies or cell line pellets can all be arrayed in the recipient block. The representative area of interest is identified and circled on a haematoxylin and eosin (H&E)-stained section of the donor block. Using a predesigned map showing a precise spacing pattern, a high density array of up to 1,000 cores of cell pellets and/or donor tissue can be embedded into the recipient block using a tissue arrayer from Beecher Instruments. Depending on the depth of the cell line/tissue removed from the donor block 100-300 consecutive sections can be cut from each CMA/TMA block. Sections can be stained for in situ detection of protein, DNA or RNA targets using immunohistochemistry (IHC), fluorescent in situ hybridisation (FISH) or mRNA in situ hybridisation (RNA-ISH), respectively. This chapter provides detailed methods for CMA/TMA design, construction and analysis with in-depth notes on all technical aspects including tips to deal with common pitfalls the user may encounter.

Molecular analysis of oral squamous cell carcinoma: a tissue microarray study

BACKGROUND

An intriguing aspect of Oral Squamous Cell Carcinomas (OSCC) is its behavioral disparity. Among patients who present with the similar clinicopathological features, some have a better prognosis than others. Identification of molecular alterations responsible for this may contribute to a greater understanding of tumor behavior. Tissue microarray (TMA) approach is a high throughput technology that enables analysis of multiple molecular targets simultaneously without causing any morphological alteration to tissue specimens.

AIM AND OBJECTIVE

To assess the tumor behavior based on the expression of p53, Bcl-2 and E-cadherin using TMA technology.

SETTINGS AND DESIGN

This was a case series analysis using tissue microarray technology.

MATERIALS AND METHODS

Formalin-fixed Paraffin-embedded (FFPE) tissue blocks of histological proven cases of OSCC (n = 30) were retrieved from the department archives. Tissue microarray blocks were constructed; 4 mum thick sections were cut and immunostained for p53, Bcl-2 and E-cadherin.

STATISTICAL ANALYSIS

Mean (SD) was used to summarize age, frequencies with percentages was used to summarize categorical variable and Chi-square test was used to find association between histopathology evaluation and expression of Bcl-2, p53, E-cadherin.

RESULTS AND CONCLUSION

Bcl-2 was the most frequently expressed biomarker. The expression of Bcl-2 was inversely related to the degree of differentiation (P = 0.005). The follow-up data showed that 63.6% of the cases that were positive for both Bcl-2 and E-cadherin were disease-free following treatment. Tissue microarray technology is a promising way to analyse multiple biomarkers simultaneously. The molecular data obtained from TMA will enhance diagnosis, provide better prognostication and will improve cancer treatment for individual patients.

Expression of FANCD2 in sporadic breast cancer and clinicopathological analysis

FANCD2 is involved in DNA damage repair and maintenance of chromosome stability. The purpose of this study was to investigate the expression of FANCD2 in sporadic breast cancer tissues and its association with clinicopathological features. A total of 162 Chinese women with invasive breast carcinoma who had no family history in first-degree relatives and 12 normal breast tissues were examined. The expression of FANCD2 was detected by immunohistochemical staining based on a tissue microarray technique. SAS system was used to analyze the data. Twenty-one out of the 162 invasive breast cancers (13%) were negative for FANCD2. The mean percentage of FANCD2 positive cells was significantly lower in breast cancers than in controls (P<0.05). FANCD2 expression was significantly inversely associated with histological grade and TNM stage (P<0.05), but not with axillary lymph node status or other conventional prognostic markers such as ER, PR, Her-2 and PCNA (P>0.05). It was suggested that FANCD2 may play a critical role in breast carcinogenesis. It may become a valuable and independent marker for identifying women with sporadic breast cancer and evaluating the prognosis.

Datamining approach for automation of diagnosis of breast cancer in immunohistochemically stained tissue microarray images

Cancer of the breast is the second most common human neoplasm, accounting for approximately one quarter of all cancers in females after cervical carcinoma. Estrogen receptor (ER), Progesteron receptor and human epidermal growth factor receptor (HER-2/neu) expressions play an important role in diagnosis and prognosis of breast carcinoma. Tissue microarray (TMA) technique is a high throughput technique which provides a standardized set of images which are uniformly stained, facilitating effective automation of the evaluation of the specimen images. TMA technique is widely used to evaluate hormone expression for diagnosis of breast cancer. If one considers the time taken for each of the steps in the tissue microarray process workflow, it can be observed that the maximum amount of time is taken by the analysis step. Hence, automated analysis will significantly reduce the overall time required to complete the study. Many tools are available for automated digital acquisition of images of the spots from the microarray slide. Each of these images needs to be evaluated by a pathologist to assign a score based on the staining intensity to represent the hormone expression, to classify them into negative or positive cases. Our work aims to develop a system for automated evaluation of sets of images generated through tissue microarray technique, representing the ER expression images and HER-2/neu expression images. Our study is based on the Tissue Microarray Database portal of Stanford university at http://tma.stanford.edu/cgi-bin/cx?n=her1, which has made huge number of images available to researchers. We used 171 images corresponding to ER expression and 214 images corresponding to HER-2/neu expression of breast carcinoma. Out of the 171 images corresponding to ER expression, 104 were negative and 67 were representing positive cases. Out of the 214 images corresponding to HER-2/neu expression, 112 were negative and 102 were representing positive cases. Our method has 92.31% sensitivity and 93.18% specificity for ER expression image classification and 96.67% sensitivity and 88.24% specificity for HER-2/neu expression image classification.

Simultaneous detection of TOP2A and HER2 gene amplification by multiplex ligation-dependent probe amplification in breast cancer

HER-2/neu gene amplification, found in certain subtypes of (breast-) cancers, is an independent prognostic factor of poor outcome and determines eligibility for systemic treatment with trastuzumab. TopoII alpha (TOP2A) gene amplification seems to be predictive of response to a class of cytostatic agents called TopoII inhibitors, which include the anthracyclines. The observed increased efficacy of anthracyclines in HER2-positive tumors is thought to arise from the close proximity of both genes on chromosome 17, where the TopoII amplification status will determine the anthracycline sensitivity. This study aimed to validate a new polymerase chain reaction-based test, called multiplex ligation-dependent probe amplification (MLPA), as a simple and quick method to simultaneously assess HER-2/neu and TopoII alpha gene amplification status in paraffin-embedded breast cancer samples. To this end, MLPA results were compared with TopoII alpha, HER2 chromogenic in situ hybridization (CISH). We also assessed TopoII alpha protein expression by immunohistochemistry. Of 353 patients, 9% showed TopoII alpha amplification by MLPA and 13% of patients were HER2 amplified. TopoII alpha amplification was seen in 42% of HER2-amplified cases and showed no high level amplification without HER2 amplification. Eleven patients displayed TopoI alpha loss (3%). Concordance between MLPA and CISH was 91% for TopoII alpha and 96% for HER2. Correlation between amplification and overexpression of TopoII alpha was significant (P=0.035), but amplification did not always predict protein overexpression. Loss of the TopoII alpha gene was almost never associated with loss of its protein. In conclusion, MLPA is an easy and accurate method to simultaneously detect breast cancer HER-2/neu and TopoII alpha copy number status in paraffin-embedded tissue, and thus an attractive supplement or alternative to CISH.

Tissue microarray: An effective high-throughput method to study the placenta for clinical and research purposes

OBJECTIVE

Tissue microarray (TMA) technology allows simultaneous examination of the expression of many molecular markers (protein, mRNA, DNA, etc.) with high-throughput. The application of this technology, to date, has been largely confined to the study of cancer. Placental pathology poses unique challenges because of the size of the organ, its complex anatomy, as well as its histological heterogeneity. The objective of this study was to assess the feasibility and efficiency of TMAs for immunohistochemistry and in situ hybridization of placental tissues.

STUDY DESIGN

TMAs were constructed using an automated tissue arrayer. Standard 0.6-mm or 1-mm microarray needles were used. Villous parenchyma, basal plate, and chorioamniotic membranes were targeted in each block. Five mum-thick TMA sections underwent immunohistochemical analysis of both cytoplasmic and nuclear antigens using a panel of antibodies against a variety of cytoplasmic [cytokeratin-7, vascular endothelial growth factor (VEGF), and protein Z], membranous (endoglin), and nuclear (c-fos and c-jun) antigens. mRNA in situ hybridization for surfactant protein A (SP-A) and chromogenic in situ hybridization for the Y chromosome (DYZ1) were also performed.

RESULTS

Validation of TMA immunoreactivity demonstrated comparable results with corresponding whole sections. When a two-tiered scoring system (positive/negative) was employed, there was agreement between two and three cores and whole tissue sections (kappa>0.7). When a three-tiered scoring system (negative, weak-positive, or strong-positive) was used, the data from three cores showed the highest agreement with whole tissue sections (kappa >0.7). In situ hybridization experiments for mRNA and DNA were also successful in that the signals were readily detectable. Successful transfer from the donor block to the recipient block differed according to the anatomical compartment. The transfer efficiency of villous parenchyma, basal plate, and chorioamniotic membranes were 96.9% (875/903), 76.7% (115/150), and 75.4% (224/297), respectively.

CONCLUSION

TMA is a practical and effective tool for high-throughput molecular analysis of the human placenta. Duplicate and triplicate cores offer agreement with whole tissue sections for two-category distinction immunostaining. TMA also affords relevant results from in situ hybridization experiments for mRNA and DNA. The major advantages are the conservation of tissues and reagents, simultaneous comparison of molecular markers in different anatomical compartments of the placenta, and reduction of experimental error.

Expression of apoptotic tumour necrosis factor receptor-associated factor, caspase recruitment domain and cell death-inducing DFF-45 effector genes in therapy-treated renal cell carcinoma

AIM

Dysfunction in apoptosis plays a role in development of renal cell carcinoma (RCC). This investigation aimed to identify expression of apoptosis-related genes not previously characterized in human RCC.

METHODS

The RCC ACHN cell line was treated with radiation plus interferon-alpha to induce significant apoptosis. Apoptosis RNA microarrays were used to compare control and treated RCC for apoptosis-regulatory genes with significantly altered expression (>or= twofold). Translational correlates were analysed using western blot. Immunohistochemistry of human RCC and non-cancerous kidney in tissue microarrays was also completed.

RESULTS

Several gene families, not well characterized in RCC, were significantly upregulated in RNA microarray. These were the tumour necrosis factor receptor-associated factors (TRAF1, 3 and 4), caspase recruitment domain (NOL3 and PYCARD), and cell death-inducing DFF-45 effector domain (ICAD/CAD) genes. The protein expression patterns did not always increase similarly, perhaps indicating some post-transcriptional controls needing further investigation. TRAF1 had significantly increased expression for RNA and protein (P<0.01). NOL3 had significantly decreased whole-cell protein expression (P<0.05), but had strongly localized nuclear positivity in RCC in the immunohistochemistry.

CONCLUSION

These newly identified RCC apoptosis genes have shown potential for improving outcome in other cancers and may prove to have the same potential in RCC with further study.

Creation, validation, and quantitative analysis of protein expression in vascular tissue microarrays

BACKGROUND

Tissue microarrays (TMAs) are collections of multiple tissue cores placed in parallel in a single acceptor block and traditionally used to investigate protein expression in neoplastic tissues. We validated the use of TMAs to investigate protein expression in vascular segments.

METHODS

Vascular tissues were collected from 100 adult subjects undergoing autopsy. A diverse set of vessels were harvested and arrayed over 17 TMAs. A total of 1377 unique tissues, each with a 1.5-mm feature size, were analyzed using histochemical and immunohistochemical (IHC) diaminobenzidine (DAB) methods.

RESULTS

Histomorphometric analysis of vascular disease demonstrated the TMA features captured the majority of the vascular alterations (intimal hyperplasia and atherosclerosis) seen in the original blood vessel section. Measurements of IHC staining intensity based on color deconvolution were used to quantify antigen abundance in defined regions of interest (ROI). Validation was performed using antibodies to connective tissue growth factor (CTGF), receptor for advanced glycation end products (AGER/RAGE), and matrix metalloproteinase 3 (MMP-3). IHC staining was highly correlated between duplicate features from the same vascular site over these three proteins.

CONCLUSION

This study validates the use of TMA technology to investigate the vascular wall utilizing staining intensity data.

Nuclear Receptor Interaction Protein (NRIP) expression assay using human tissue microarray and immunohistochemistry technology confirming nuclear localization

Background

A novel human nuclear receptor interaction protein (NRIP) has recently been discovered by Chen SL et al, which may play a role in enhancing the transcriptional activity of steroid nuclear receptors in prostate (LNCaP) and cervical (C33A) cancer cell lines. However, knowledge about the biological functions and clinical implications of NRIP, is still incomplete. Our aim was to determine the distribution of NRIP expression and to delineate the cell types that express NRIP in various malignant tumors and healthy non-pathological tissues. This information will significantly affect the exploration of its physiological roles in healthy and tumor cells.

Methods

By using tissue microarray (TMA) technology and an anti-NRIP monoclonal antibody immunohistochemical (IHC) survey, NRIP expression was examined in 48 types of tumors and in a control group of 48 matched or unmatched healthy non-neoplastic tissues.

Results

Our survey results showed that ten cases were revealed to express the NRIP in six malignancies (esophageal, colon, breast, ovarian, skin, and pancreatic cancers), but not all of these specific tumor types consistently showed positive NRIP expression. Moreover, malignant tumors of the stomach, prostate, liver, lung, kidney, uterine cervix, urinary bladder, lymph node, testis, and tongue revealed no NRIP expression. Among the control group of 48 matched and unmatched non-neoplastic tissues, all of them demonstrated IHC scores less than the cut-off threshold of 3. In addition, ten cores out of thirty-six carcinomatous tissues revealed positive NRIP expression, which indicated that NRIP expression increases significantly in carcinoma tissue cores, comparing to the matched controlled healthy tissues.

Conclusion

This is the first study to use a human TMA and IHC to validate the nuclear localization for this newly identified NRIP expression. In considering the use of NRIP as a potential diagnostic tool for human malignancies survey, it is important to note that NRIP expression carries a sensitivity of only 23%, but has a specificity of 100%. There is also a significant difference in positive NRIP expression between primary carcinomatous tissues and matched controlled healthy tissues. Although further large-scale studies will merit to be conducted to evaluate its role as a potential adjunct for cancer diagnosis, data from this study provides valuable references for the future investigation of the biological functions of NRIP in humans.

Banking human tissue for research: vision to reality

Advances in scientific understanding of disease together with introduction of new high throughput technologies have led to increased demand for human tissue in research. In general, patients are willing to donate for research, particularly samples that are surplus to diagnostic or therapeutic requirements. New tissue-specific regulations in the UK are intended to facilitate the use of human tissue in research. Despite this positive environment there are challenges to researcher access. Coordinated, systematic collection and storage, via a biobank can provide easier access. However translating a vision for a biobank into reality whether in the public or private sector, has never been simple. But it can be done.