Development of a Stable Peptide-Based PET Tracer for Detecting CD133-Expressing Cancer Cells

Background Boron neutron capture therapy (BNCT) is a molecular radiation therapy approach based on the 10B (n, α) 7Li nuclear reaction in cancer cells. In BNCT, delivery of 10B in the form of 4-borono-phenylalanine conjugated with fructose (BPA-fr) to the cancer cells is important. The PET tracer 4-borono-2-18F-fluoro-phenylalanine (FBPA) has been used to predict the accumulation of BPA-fr before BNCT. Purpose To determine the biodistribution and dosimetric parameters in 18F-BPA PET/CT studies. Material and Methods Human biokinetic data were obtained during clinical 18F-BPA PET studies between February and June 2015 at one institution. Nine consecutive patients were studied prospectively. The internal radiation dose was calculated on the basis of radioactivity data from blood, urine, and normal tissue of the heart, liver, spleen, kidney, and other parts of the body at each time point using OLINDA/EXM1.1 program. We compared our calculations with published 18F-FDG data. Results Adult patients (3 men, 3 women; age range, 28–68 years) had significantly smaller absorbed doses than pediatric patients (3 patients; age range, 5–12 years) ( P = 0.003). The mean effective dose was 57% lower in adult patients compared with pediatric patients. Mean effective doses for 18F-BPA were 25% lower than those for 18F-FDG presented in International Commission of Radiation Protection (ICRP) publication 106. Conclusion We found significant differences in organ absorbed doses for 18F-BPA against those for 18F-FDG presented in ICRP publication 106. Mean effective doses for 18F-BPA were smaller than those for 18F-FDG in the publication by 0.5–38% (mean difference, 25%).

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Ultrastructural modification of cellular interactions in cancer tumor

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082455 ◽

1978 ◽

Vol 36 (2) ◽

pp. 318-319

Author(s):

N. P. Dmitrieva

Keyword(s):

Cancer Cells ◽

Human Thyroid ◽

Adjacent Cell ◽

Main Role ◽

Cellular Interactions ◽

Electron Microscopic ◽

Cancer Tumor ◽

Normal Human ◽

Characteristic Features

One of the most characteristic features of cancer cells is their ability to metastasia. It is suggested that the modifications of the structure and properties of cancer cells surfaces play the main role in this process. The present work was aimed at finding out what ultrastructural features apear in tumor in vivo which removal of individual cancer cells from the cell population can provide. For this purpose the cellular interactions in the normal human thyroid and cancer tumor of this gland electron microscopic were studied. The tissues were fixed in osmium tetroxide and were embedded in Araldite-Epon.In normal human thyroid the most common type of intercellular contacts was represented by simple junction formed by the parallelalignment of adjacent cell membranees leaving in between an intermembranes space 15-20 nm filled with electronlucid material (Fig. 1a). Sometimes in the basal part of cells dilatations of the intercellular space 40-50 nm wide were found (Fig. 1a). Here the cell surfaces may form single short microvilli.

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Ultrastructural Localization Study of Carcinoembryonic Antigen (CEA) in Gastric Cancer: Immunoelectron Microscopic Observation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158807 ◽

1990 ◽

Vol 48 (3) ◽

pp. 252-253

Author(s):

Dong Yuming ◽

Yang Guanglin ◽

Wu Jifeng ◽

Chen Xiaolin

Keyword(s):

Gastric Cancer ◽

Intestinal Metaplasia ◽

Cancer Cells ◽

Microscopic Observation ◽

Biological Significance ◽

Ultrastructural Localization ◽

Mucinous Carcinoma ◽

Surface Glycoprotein ◽

Tubular Adenocarcinoma ◽

Pap Method

On the basis of light microscopic observation, the ultrastructural localization of CEA in gastric cancer was studied by immunoelectron microscopic technique. The distribution of CEA in gastric cancer and its biological significance and the mechanism of abnormal distribution of CEA were further discussed.Among 104 surgically resected specimens of gastric cancer with PAP method at light microscopic level, the incidence of CEA(+) was 85.58%. All of mucinous carcinoma exhibited CEA(+). In tubular adenocarcinoma the incidence of CEA(+) showed a tendency to rising with the increase of degree of differentiation. In normal epithelia and intestinal metaplasia CEA was faintly present and was found only in the luminal surface. The CEA staining patterns in cancer cells were of three types--- cytoplasmic, membranous and weak reactive type. The ultrastructural localization of CEA in 14 cases of gastric cancer was studied by immunoelectron microscopic technique.There was a little or no CEA in the microvilli of normal epithelia. In intestinal metaplasia CEA was found on the microvilli of absorptive cells and among the mucus particles of goblet cells. In gastric cancer CEA was also distributed on the lateral and basal surface or even over the entire surface of cancer cells and lost their polarity completely. Many studies had proved that the alterations in surface glycoprotein were characteristic changes of tumor cells. The antigenic determinant of CEA was glycoprotein, so the alterations of tumor-associated surface glycoprotein opened up a new way for the diagnosis of tumors.

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Water-soluble amphiphilic ruthenium(ii) polypyridyl complexes as potential light-activated therapeutic agents

Chemical Communications ◽

10.1039/d0cc04397d ◽

2020 ◽

Vol 56 (65) ◽

pp. 9332-9335

Author(s):

Sandra Estalayo-Adrián ◽

Salvador Blasco ◽

Sandra A. Bright ◽

Gavin J. McManus ◽

Guillermo Orellana ◽

...

Keyword(s):

Cervical Cancer ◽

Cancer Cells ◽

Cellular Uptake ◽

Therapeutic Agents ◽

Water Soluble ◽

Polypyridyl Complexes ◽

Cervical Cancer Cells

Two new water-soluble amphiphilic Ru(ii) polypyridyl complexes were synthesised and their photophysical and photobiological properties evaluated; both complexes showed a rapid cellular uptake and phototoxicity against HeLa cervical cancer cells.

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