scholarly journals The Enhanced Permeability and Retention (EPR) Effect: The Significance of the Concept and Methods to Enhance Its Application

2021 ◽  
Vol 11 (8) ◽  
pp. 771
Author(s):  
Jun Wu
Keyword(s):  
Clinical Practice ◽  
Solid Tumor ◽  
Tumor Tissue ◽  
Fundamental Problem ◽  
Anticancer Compounds ◽  
Epr Effect ◽  
Enhanced Permeability And Retention ◽  
Satisfactory Outcome ◽  
Targeting Delivery ◽  
Solid Tumor Tissue

Chemotherapy for human solid tumors in clinical practice is far from satisfactory. Despite the discovery and synthesis of hundreds of thousands of anticancer compounds targeting various crucial units in cancer cell proliferation and metabolism, the fundamental problem is the lack of targeting delivery of these compounds selectively into solid tumor tissue to maintain an effective concentration level for a certain length of time for drug-tumor interaction to execute anticancer activities. The enhanced permeability and retention effect (EPR effect) describes a universal pathophysiological phenomenon and mechanism in which macromolecular compounds such as albumin and other polymer-conjugated drugs beyond certain sizes (above 40 kDa) can progressively accumulate in the tumor vascularized area and thus achieve targeting delivery and retention of anticancer compounds into solid tumor tissue. Targeting therapy via the EPR effect in clinical practice is not always successful since the strength of the EPR effect varies depending on the type and location of tumors, status of blood perfusion in tumors, and the physical-chemical properties of macromolecular anticancer agents. This review highlights the significance of the concept and mechanism of the EPR effect and discusses methods for better utilizing the EPR effect in developing smarter macromolecular nanomedicine to achieve a satisfactory outcome in clinical applications.

Direct measurement of the extravasation of polyethyleneglycol-coated liposomes into solid tumor tissue by in vivo fluorescence microscopy

1996 ◽  
Vol 144 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Sakae Unezaki ◽  
Kazuo Maruyama ◽  
Jun-Ichi Hosoda ◽  
Itsuro Nagae ◽  
Yasuhisa Koyanagi ◽  
...  
Keyword(s):  
Fluorescence Microscopy ◽  
Direct Measurement ◽  
Solid Tumor ◽  
Tumor Tissue ◽  
In Vivo Fluorescence ◽  
Solid Tumor Tissue

scholarly journals Representative Sequencing: Unbiased Sampling of Solid Tumor Tissue

2019 ◽  
Author(s):  
Dr Kevin Litchfield ◽  
Stacey Stanislaw ◽  
Lavinia Spain ◽  
Lisa Gallegos ◽  
Andrew Rowan ◽  
...  
Keyword(s):  
Solid Tumor ◽  
Tumor Tissue ◽  
Solid Tumor Tissue

Using intraoperative dynamic contrast-enhanced T1-weighted MRI to identify residual tumor in glioblastoma surgery

2014 ◽  
Vol 120 (1) ◽  
pp. 60-66 ◽  
Author(s):  
Koray Özduman ◽  
Erdem Yıldız ◽  
Alp Dinçer ◽  
Aydın Sav ◽  
M. Necmettin Pamir
Keyword(s):  
Solid Tumor ◽  
Tumor Tissue ◽  
Residual Tumor ◽  
Dynamic Contrast Enhanced Mri ◽  
Dynamic Contrast Enhanced ◽  
Enhanced Mri ◽  
Contrast Enhanced ◽  
Solid Tumor Tissue ◽  
Surgically Induced ◽  
Contrast Enhanced Mri

Object The goal of surgery in high-grade gliomas is to maximize the resection of contrast-enhancing tumor without causing additional neurological deficits. Intraoperative MRI improves surgical results. However, when using contrast material intraoperatively, it may be difficult to differentiate between surgically induced enhancement and residual tumor. The purpose of this study was to assess the usefulness of intraoperative dynamic contrast-enhanced T1-weighted MRI to guide this differential diagnosis and test it against tissue histopathology. Methods Preoperative and intraoperative dynamic contrast-enhanced MRI was performed in 21 patients with histopathologically confirmed WHO Grade IV gliomas using intraoperative 3-T MRI. Standardized regions of interest (ROIs) were placed manually at 2 separate contrast-enhancing areas at the resection border for each patient. Time-intensity curves (TICs) were generated for each ROI. All ROIs were biopsied and the TIC types were compared with histopathological results. Pharmacokinetic modeling was performed in the last 10 patients to confirm nonparametric TIC analysis findings. Results Of the 42 manually selected ROIs in 21 patients, 25 (59.5%) contained solid tumor tissue and 17 (40.5%) retained the brain parenchymal architecture but contained infiltrating tumor cells. Time-intensity curves generated from residual contrast-enhancing tumor and their preoperative counterparts were comparable and showed a quick and persistently increasing slope (“climbing type”). All 17 TICs obtained from regions that did not contain solid tumor tissue were undulating and low in amplitude, compared with those obtained from residual tumors (“low-amplitude type”). Pharmacokinetic findings using the transfer constant, extravascular extracellular volume fraction, rate constant, and initial area under the curve parameters were significantly different for the tumor mass, nontumoral regions, and surgically induced contrast-enhancing areas. Conclusions Intraoperative dynamic contrast-enhanced MRI provides quick, reproducible, high-quality, and simply interpreted dynamic MR images in the intraoperative setting and can aid in differentiating surgically induced enhancement from residual tumor.

scholarly journals The Way that PEGyl-DSPC Liposomal Doxorubicin Particles Penetrate into Solid Tumor Tissue

2006 ◽  
Vol 1 ◽  
pp. 117739280600100 ◽  
Author(s):  
Xing Qing Pan ◽  
Susie Jones ◽  
Karen Cox
Keyword(s):  
Solid Tumor ◽  
Liposomal Doxorubicin ◽  
Tumor Tissue ◽  
Solid Tumor Tissue ◽  
The Way

RNA Isolation from Solid Tumor Tissue

1995 ◽  
Vol 228 (1) ◽  
pp. 170-172 ◽  
Author(s):  
J. Kitlinska ◽  
J. Wojcierowski
Keyword(s):  
Solid Tumor ◽  
Tumor Tissue ◽  
Rna Isolation ◽  
Solid Tumor Tissue

scholarly journals THE INTRA-ASSAY PRECISION AND TIME STABILITY OF QUANTITATIVE βIII-TUBULIN EXPRESSION ASSESSMENT IN SOLID TUMOR TISSUE

2020 ◽  
Vol 19 (3) ◽  
pp. 52-56
Author(s):  
A. A. Basharina ◽  
T. A. Bogush ◽  
E. A. Rukavishnikova ◽  
E. A. Bogush ◽  
S. A. Kaliuzhny ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Solid Tumors ◽  
Solid Tumor ◽  
Tumor Tissue ◽  
Quantitative Estimation ◽  
Flow Cytometer ◽  
Time Stability ◽  
Analytical Validation ◽  
Assay Precision ◽  
Solid Tumor Tissue

Introduction. The introducing of tumor molecular profiling into clinical practice has revealed the need for development of new analytical methods for estimating marker expression in solid tumors, as routinely used method of immunohistochemistry has a number of significant drawbacks.Objective. Analytical validation of immunofluorescence staining and flow cytometry method developed by the authors for the examination of tumor protein markers in the solid tumors tissue.Materials and methods. Method validation was carried out by quantitative estimation of βIII-tubulin (TUBB3) expression in single-cell suspensions of non-small-cell lung cancer obtained from surgical tumor samples. Primary antibodies to TUBB3 (ab7751) and secondary DyLight 650-conjugated antibodies (ab98729) were used for immunofluorescent staining. The «Navios» flow cytometer (Beckman Coulter) was used to measure the fluorescence. The validation parameters were assessed by the coefficient of variation calculated as the ratio of standard deviation of TUBB3 level to its mean value.Results. Two parameters were analyzed: intra-assay precision and time stability of the results of the TUBB3 expression assessment. It was demonstrated that the mean coefficients of variation of the marker expression level in the tumor tissue did not exceed 20 % for both parameters. According to recommendations on the analytical validation of methods based on flow cytometry, it proves the validity of the method for these parameters.Conclusions. The intra-assay precision and time stability were demonstrated for the results of a quantitative estimation of TUBB3 expression in solid tumor tissue using immunofluorescence staining and flow cytometry method developed by the authors. The practical value of the time stability of immunofluorescence stain during 24 h storage of a stained cells suspension in the dark at 4 °C was highlighted. It shows the possibility of adjusting the time interval between completion of the analytical study part and flow cytometer measurement.

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