Cancer tissue

The development of so-called photodynamic therapy uses lasers for treatment of cancer. The patient is injected with a substance called hematoporphyrin derivative [68335-15-9] which is preferentially localized in cancerous tissues. The patient is later irradiated with laser light, often with a dye laser at a wavelength around 630 nm. The light energy catalyticaHy photooxidizes the hematoporphyrin derivative, releasing materials which kill the nearby cancerous tissue. Normal tissue which did not retain the chemical is not harmed. Photodynamic therapy offers promise as a new form of cancer treatment. 

The recoiling a-particle ( He) and lithium nucleus (]U) between them carry 2.4 MeV of energy and this is shed within just a few m, the a-particle travelling about 9fim and the Li nucleus about S.S im in the opposite direction. The radiation damage is thus confined within the cancerous tissue alone. 

Erebs-behandlung, /. treatment of cancer, -gewebe, n. cancerous tissue. 

ALG-2 is the fust calcium-binding protein of the EF-hand family found to be directly involved in apoptosis. ALG-2 is a 22 kDa protein and like the other members of the penta EF-hand family, contains five EF-hands, with only two of them functional. ALG-2 protein is expressed in the brain and eye and was found to be upregulated in various cancer tissues. Several targets have been found, such as proteins AEP, Alix, preflin, and annexins, suggesting a putative role of ALG-2 in apoptosis. 

Technetium isotopes also help tremendously in the diagnosis of breast cancer. A technetium complex preferentially binds to cancer cells, so if a patient has cancer, radioactivity imaging will reveal high levels of radioactivity from the cancerous tissues. The red spot in the image below marks the location of cancerous cells. 

Keshavarzian, A., Zapeda, D., List, T. and Mobarhan, S. (1992d). High levels of reactive oxygen metabolites in colon cancer tissues analysis by chemiluminescence probe. Nutr. Cancer 17, 243-249. 

Olinski, R., Zastawny, T., Budzbon, J., Skokowski, J., Zegarski, W. and Dizdaroglu, M. (1992). DNA base modifications in chromatin of human cancerous tissues. FEBS Lett. 309, 193-198. 

Cervical cancer tissue characterized by high-resolution magic angle spinning MR spectroscopy, MAGMA), Magn. Re-son. Mater. Phys., Biol. Med. 16, 174-181. 

The beauty of MRI in medical imaging is its sensitivity to different chemical or physical properties that give useful contrasts between volumes having different properties, for example, cancerous tissue versus normal tissue, both having similar density. This greatly reduces the need for accurate density measurements because it shifts the burden of image contrast to a parameter that is more sensitive than density. 

First, a limited study was performed using breast cancer tissue to establish an optimal protocol of DNA extraction for a-CGH analysis that would allow comparison of a-CGH results after boiling in different solutions three pH values of 7, 9, and 12 of Britton and Robinson buffer solution, and a 0.1 M sodium hydroxide solution. DNA samples extracted from frozen and from FFPE tissue sections by a nonheating protocol were employed, and the results were compared a protocol of boiling samples in 0.1 M sodium hydroxide gave optimal results. 

Specht et al.60 Microdissected cancer tissues RNA lysis buffer containing SDS and proteinase K Real time, for seven cancerrelevant genes Reproducible quantitation of specific mRNAs can be achieved... 

Compound (Miles Laboratories, Elkhart, IN), snap-frozen, and cut into sections for comparison with paraffin-embedded cell sections (3) FFPE Cell Blocks Six cell pellets were fixed in 10% neutral buffered formalin immediately after harvest, at room temperature for 6,12,24h, 3,7, and 30 days, respectively. For further comparison with the cell model system, recently collected sample of human breast cancer tissues were processed by OCT-embedding and snap-freezing the corresponding routine FFPE block that was obtained from the Norris Cancer Hospital and Research Institute at the University of Southern California Keck School of Medicine (USC). This tissue block was processed routinely (formalin-fixed 24h and processed by automatic equipment). 

Daigo Y, Chin S-F, Gorringe KL, et al. Degenerate oligonucleotide primed-polymerase chain reaction-based array comparative genomic hybridization for extensive Amplicon profiling of breast cancers. A new approach for the molecular analysis of paraffin-embedded cancer tissue. Am. J. Pathol. 2001 158 1623-1631. 

Figure 5.2 Comparison of immunohistochemical staining results among variable periods, 6 h to 30 days, of formalin-fixed, paraffin-embedded human breast cancer tissue (A-N), and cell line MCF-7 sections (O-Bl). All four markers, estrogen receptor (ER) (A-G), CK (cytokeratin cocktail, H-N), Her2/neu (O-U), and MIB-1 (V-Bl), showed comparable positive immunostaining results at +++ level after antigen retrieval. Original magnification x 200. Bar = 50 tm. Reproduced with permission from Shi et al., I Histochem. Cytochem. 2007 55 105-109. See color insert.

At Leica Biosystems Newcastle Ltd., invasive breast cancer tissue controls, demonstrating HER2 expression levels at 3+, 2+, 1+, and 0, are incorporated into all Oracle HER2 Bond IHC System cell line quality control runs. This ensures that control cell lines are validated as a viable assay control. The evaluation of control cell lines should always be performed within the context of appropriate tolerance limits. Subtle changes from batch to batch may occur, and it is the correct evaluation of the cell line staining patterns within appropriate tolerance limits that enables control cell lines to be utilized both in a commercial setting and as an EQA monitoring device. 

Hood BL, Darfler MM, Guiel TG, et al. Proteomic analysis of formalin-fixed prostate cancer tissue. Mol. Cell. Proteomics 2005 4 1741-1753. 

Hwang SI, Thumar J, Lundgren DH, et al. Direct cancer tissue proteomics a method to identify candidate cancer biomarkers from formalin-fixed paraffin-embedded archival tissues. Oncogene 2006 26 65-76. 

Figure 5.2 Comparison of immunohistochemical staining results among variable periods, 6 h to 30 days, of formalin-fixed, paraffin-embedded human breast cancer tissue (A-N), and cell line MCF-7 sections (O-Bl). (See text for full caption).

Nanosized objects perform various functions in the biomedical field. In the human body, nanosized particulate substances behave very differently from larger particles. In 1986, Maeda et al. found that the stained albumin, having a size of several nanometers, naturally accumulates in the region of cancerous tissues, which is now well known as the enhanced permeability and retention (EPR) effect. Many studies in the field of nanoparticles are based on this finding. Another application of nanoparticles is the delivery system using various polyplexes that are composed of carrier molecules and plasmid DNA or nucleic acid drugs such as antisenses and siRNA. In addition, nanofibers are mainly used for biodegradable scaffolds in tissue... 

In 1965 1967 a great interest has been attached to the possible role of free radicals in cancer after studies by Emanuel and his coworkers who reported the excessive production of free radicals in tumor cells (see, for example, Ref. [145]). On these grounds the authors suggested to apply antioxidant therapy for the treatment of cancer patients. Unfortunately, experimental proofs of overproduction of free radicals in cancer tissue turn out to be erroneous [146], A new interest in the role of free radicals in cancer development emerged after the discovery of superoxide and superoxide dismutases. 

To date, 16 GST isozymes have been found in humans [48]. Studies of several cancer tissues have revealed the overexpression of different GST isozymes, with GST Pl-1 (GST Pi, GST ji) being the most predominant. For this reason, GST Pl-1 is regarded as a potential tumor marker [5,49-53]. The high expression levels of GST Pl-1 (up to 2.7% of the total cytosolic protein [52]), combined with its detoxification role against xenobiotics, make GST Pl-1 a major player responsible for drug resistance in patients undergoing anticancer chemotherapy [49]. 

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