Immunohistochemistry (IHC), also referred to as immunocytochemistry in cytology literature, has revolutionized the practice of cytopathology. Because of the complexity of cytology preparation and limited diagnostic material, performing IHC remains a challenge. Formalin-fixed paraffin-embedded (FFPE) cell block (CB) is the optimal choice for IHC.
View Article and Find Full Text PDFJ Histochem Cytochem
January 2023
Appl Immunohistochem Mol Morphol
July 2020
This review article summarized recent advances in the heat-induced antigen retrieval technique with numerous scientific fields in addition to immunohistochemistry. Particularly, proteomics including imaging mass spectrometry, extraction of proteins from formalin-fixed, paraffin-embedded (FFPE) tissues. Some novel approaches such as FFPE tissue-based renal immunopathology based on modified double heating protocols are also introduced in this review for further development.
View Article and Find Full Text PDFBackground: Traditional single-marker and multimarker molecular profiling approaches in bladder cancer do not account for major risk factors and their influence on clinical outcome. This study examined the prognostic value of molecular alterations across all disease stages after accounting for clinicopathological factors and smoking, the most common risk factor for bladder cancer in the developed world, in a population-based cohort.
Methods: Primary bladder tumors from 212 cancer registry patients (median follow-up, 13.
Introduction: Retrospective studies suggest that p53 alteration is prognostic for recurrence in patients with urothelial bladder cancer and predictive for benefit from combination methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) adjuvant chemotherapy.
Patients And Methods: Patients with pT1/T2N0M0 disease whose tumors demonstrated ≥ 10% nuclear reactivity on centrally performed immunohistochemistry for p53 were offered random assignment to three cycles of adjuvant MVAC versus observation; p53-negative patients were observed. By using a log-rank test with one-sided α = .
As a review for the 20th anniversary of publishing the antigen retrieval (AR) technique in this journal, the authors intend briefly to summarize developments in AR-immunohistochemistry (IHC)-based research and diagnostics, with particular emphasis on current challenges and future research directions. Over the past 20 years, the efforts of many different investigators have coalesced in extending the AR approach to all areas of anatomic pathology diagnosis and research and further have led to AR-based protein extraction techniques and tissue-based proteomics. As a result, formalin-fixed paraffin-embedded (FFPE) archival tissue collections are now seen as a literal treasure of materials for clinical and translational research to an extent unimaginable just two decades ago.
View Article and Find Full Text PDFTo examine the use of acetone- or ethanol-fixed frozen tissue sections as the "gold standard" for immunohistochemical analysis, we evaluated frozen sections with various conditions of fixation and antigen retrieval (AR). Fresh human tissues were frozen in OCT. An adjacent tissue block was fixed in 10% neutral buffered formalin (NBF) and paraffin embedded (FFPE).
View Article and Find Full Text PDFFormalin-fixed and paraffin-embedded tissues represent the vast majority of archived tissue. Access to such tissue specimens via shotgun-based proteomic analyses may open new avenues for both prospective and retrospective translational research. In this study, we evaluate the effects of fixation time on antigen retrieval for the purposes of shotgun proteomics.
View Article and Find Full Text PDFZhonghua Bing Li Xue Za Zhi
January 2007
Background: Induction of molecular chaperone Grp78 (78-kDa glucose-regulated protein) occurs in stress conditions that often characterize tumor microenvironments. We investigated the role of Grp78 in prostate cancer progression and the development of castration resistance, where cancer cells continue to survive despite the stress of an androgen-starved environment.
Experimental Design: Immunohistochemistry was done to examine Grp78 expression in 219 prostate cancers from patients with pathologic stage T3N0M0 disease [androgen ablation naive (untreated) and androgen ablation exposed (treated)] and castration-resistant prostate cancer.
From a practical point of view, one of the most difficult issues in the standardization of IHC for FFPE tissue is the adverse influence of formalin upon antigenicity, as well as the great variation in fixation/processing procedures. Based on previous study, an additional study using four markers demonstrated the potential for obtaining equivalent IHC staining among FFPE tissue sections with periods of formalin fixation ranging from 6 hr to 30 days. On this basis, the following hypothesis is proposed.
View Article and Find Full Text PDFA satisfactory protocol of protein extraction has been established based on the heat-induced antigen retrieval (AR) technique widely applied in immunohistochemistry for archival formalin-fixed, paraffin-embedded (FFPE) tissue sections. Based on AR, an initial serial experiment to identify an optimal protocol of heat-induced protein extraction was carried out using FFPE mouse tissues. The optimal protocol for extraction of proteins was then performed on an archival FFPE tissue of human renal carcinoma.
View Article and Find Full Text PDFObjective: To investigate the role of potential downstream targets of HER-2/neu, including the cell-cycle regulator p27, proliferation-associated protein Ki-67, apoptosis inhibitor Bcl-2, and signal-transduction molecule Akt (which is associated with cell survival), as the development of androgen-independent prostate cancer (AIPC) in patients who are initially responsive to androgen-ablation therapy (AAT) is a significant clinical problem.
Patients And Methods: Earlier studies showed that high levels of HER-2/neu tyrosine kinase receptor expression as assessed by immunohistochemistry were significantly associated with the development of AIPC, and we hypothesised that HER-2/neu overexpression provides an alternative proliferative stimulus upon androgen depletion. We established a unique clinical model system, comprising patients who received no AAT, or who had preoperative AAT, or those with advanced tumours resistant to AAT.
A serial study was performed to develop a protein-embedding technique for standardization of immunohistochemistry (IHC) on formalin-fixed, paraffin-embedded (FFPE) tissue sections. A protein carrier matrix must have two phases, a liquid phase to allow uniform mixing of a protein and a solid phase forming a 'block' that can be fixed and processed in the same manner as human tissue. This standardized protein block would serve as a source of thin sections for control of IHC and therefore must also withstand the boiling conditions of antigen retrieval (AR).
View Article and Find Full Text PDFBased on the antigen retrieval principle, our previous study has demonstrated that heating archival formalin-fixed, paraffin-embedded (FFPE) tissues at a higher temperature and at higher pH value of the retrieval solution may achieve higher efficiency of extracted DNA, when compared to the traditional enzyme digestion method. Along this line of heat-induced retrieval, this further study is focused on development of a simpler and more effective heat-induced DNA retrieval technique by testing various retrieval solutions. Three major experiments using a high temperature heating method to extract DNA from FFPE human lymphoid and other tissue sections were performed to compare: (1) different concentrations of alkaline solution (NaOH or KOH, pH 11.
View Article and Find Full Text PDFLoss of heterozygosity, mutations or deletions of the RB1 gene usually result in loss of pRb expression, which has been regarded as an indicator of loss of pRb function in human tumours. It has previously been shown that in addition to loss of pRb expression, aberrantly high (pRb2+) pRb expression also indicates loss of pRb function in bladder tumours compared with moderate (normal, pRb1+) pRb expression. The aim of this study was to elucidate the mechanism by which pRb is functionally inactivated in bladder tumours expressing aberrantly high levels of pRb.
View Article and Find Full Text PDFPurpose: To determine the combined effects of p53, p21, and pRb alterations in predicting the progression of bladder transitional cell carcinoma.
Patients And Methods: p53, p21, and pRb expression was examined immunohistochemically on archival radical cystectomy samples from 164 patients with invasive or high-grade recurrent superficial transitional cell carcinoma (TCC; lymph node-negative, 117 patients; lymph node-positive, 47 patients). Median follow-up was 8.
Appl Immunohistochem Mol Morphol
December 2002
Antigen retrieval is now a standard procedure in immunohistochemical studies of tissues for diagnosis and research. While the most commonly used protocol (20 minutes at 100 degrees C in citrate buffer pH 6.0) is effective for many antibody/antigen combinations, experience has shown that in some instances, this standard approach fails.
View Article and Find Full Text PDFDuring the course of diagnostic surgical pathology, pathologists have established a large collection of formalin-fixed, paraffin-embedded tissues that form invaluable resources for translational studies of cancer and a variety of other diseases. Accessibility of macromolecules in the fixed tissue specimens is a critical issue as exemplified by heat-induced antigen retrieval (AR) immunohistochemical (IHC) staining. On the basis of observations that heating may also enhance in situ hybridization (ISH) and the similarity of formalin-induced chemical modifications that occur in protein and in DNA, we designed a study to examine the efficiency of DNA extraction from archival formalin-fixed, paraffin-embedded tissues using an adaptation of the basic principles of the AR technique, i.
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