phytochlorin and Adenocarcinoma

To develop a photosensitizer, chlorin e6 (Ce6)-based amphiphilic polymer, DP-Ce6, where DOPE and PEG are conjugated to Ce6, which would self-assemble to form polymeric micelles (DP-Ce6-M) in aqueous environment.. DP-Ce6-M were characterized for particle size, zeta potential, and singlet oxygen (. DP-Ce6-M formed stable micelles with particles size of 58.2 ± 1.6 nm. Solubility of Ce6 was improved. Photoactivity of DP-Ce6-M was sustained in regard to

Topics: Adenocarcinoma; Cell Line, Tumor; Chlorophyllides; Female; Humans; Lipids; Micelles; Nanoparticles; Particle Size; Phosphatidylethanolamines; Photochemotherapy; Photosensitizing Agents; Polyethylene Glycols; Polymers; Porphyrins; Uterine Neoplasms

Sonodynamic therapy (SDT) is a promising new approach for cancer therapy. The aim of this study was to investigate the tumor affinity of chlorin e6, a photosensitizer, and its sonodynamic effects on NSCLC.. Human lung adenocarcinoma cells SPCA-1 and mice bearing SPCA-1 tumor xenograft were exposed to ultrasound in the presence or absence of chlorin e6. Chlorin e6 distribution was detected by laser scan confocal microscope. Cell apoptosis and necrosis were studied by flow cytometry analysis. Tumor size and weight were measured after different treatments.. The concentration of chlorin e6 in tumor tissue was remarkably higher than that in normal muscle near tumor, and the difference was greatest at 18h (the fluorescence intensity was 5.38-fold higher in tumor than in muscle, P<0.05). In vivo, ultrasound (0.4-1.6W/cm(2)) or chlorin e6 (10-40mg/kg) alone had no remarkable anti-tumor effects, but the combination of ultrasound (1.6W/cm(2)) with chlorin e6 (SDT) hampered tumor growth significantly (P<0.05). Intraperitoneal injection of 40mg/kg chlorin e6 exerted no notable side effect on blood, liver and kidney function. Flow cytometry analysis showed that chlorin e6-mediated sonodynamic effect was mainly through the induction of cell necrosis.. Chlorin e6 is a promising sonosensitizer and chlorin e6-mediated SDT may provide a new approach for NSCLC therapy.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Chlorophyllides; Female; Flow Cytometry; Humans; Lung Neoplasms; Mice; Porphyrins; Ultrasonic Therapy; Xenograft Model Antitumor Assays

Sonodynamic therapy (SDT) is a promising new approach for cancer therapy. The purpose of this study is to detect the effects of SDT on the cell proliferation of human lung adenocarcinoma cell SPCA-1, using Chlorin e6 as a sonosensitizing agent activated by ultrasound.. SPCA-1 and normal peripheral mononuclear cell (PMNC) were treated with ultrasound or Chlorin e6 alone and combined. Cell proliferation was determined by MTT assay, and cell morphology was studied by inverted microscope after 6 h treated.. 1.0 MHz ultrasound (1.0 W/ cm(2)-2.0 W/cm2 x 60 s) and Chlorin e6 (0.4 mg/mL-3.2 mg/mL) inhibited the cell proliferation of both SPCA-1 and PMNC cells in a intensity- and a dose-dependent manner respectively. Compared with the ultrasound (1.0 W/cm2 x 60 s) or Chlorin e6 (0.05 mg/mL-0.2 mg/mL) alone, the inhibitory effect on the cell proliferation was remarkably increased by the combination of ultrasound and chlorin e6 in SPCA-1 cells (P < 0.05), but no same effect was observed in PMNC cells (P > 0.05). Compared with the ultrasound (1.0 W/cm2 x 60 s) or chlorin e6 (0.2 mg/mL) alone, the combination treatment of ultrasound with Chlorin e6 induced more necrotic cells in SPCA-1 cells (P < 0.05).. There was a significant selectively inhibitory effect of sonodynamic effect with Chlorin e6 on the SPCA-1 cell growth. Chlorin e6 may be a promising sonosensitizing agent for the treatment of non-small cell lung cancer.

Topics: Adenocarcinoma; Cell Line, Tumor; Chlorophyllides; Humans; Lung Neoplasms; Porphyrins; Radiation-Sensitizing Agents; Ultrasonic Therapy

The transferrin receptor is often highly expressed in tumor cells whereas it is usually present at low levels in surrounding normal adult tissue. Here, a potential anti-cancer agent is described, which is directed at this receptor and consists of a toxin-modified transferrin, which is activated via photodynamic therapy. The porphyrin chlorin e6 was conjugated to transferrin using a procedure, which involved the preliminary binding of the protein to quaternary amino ethyl-sephadex. This maintained the natural activity of the transferrin, and the un-activated conjugate exhibited no in vitro cellular toxicity. The conjugate's singlet oxygen yield was estimated by assessment of its light-dependent oxidation of tetramethylbenzidine, where it displayed approximately 70% of the efficiency of native chlorin e6. When chlorin e6-transferrin treated human MCF7 and rat MTLn3 mammary adenocarcinoma cells were exposed to toxin-activating visible light, a tumor cell killing effect was achieved in normal (medium plus 10% FBS) culture conditions with an ED50 of approximately 10-20 microg/ml. A method for the synthesis of chlorin e6-transferrin was developed, and the conjugate was shown to exhibit a light-dependent killing of mammary adenocarcinoma cells in culture. The conjugate demonstrated potential as an anti-cancer agent.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Breast Neoplasms; Chlorophyllides; Drug Screening Assays, Antitumor; Female; Humans; Immunotoxins; Photochemotherapy; Porphyrins; Radiation-Sensitizing Agents; Rats; Receptors, Transferrin; Transferrin; Tumor Cells, Cultured

Certain tumor cells, such as squamous carcinoma cells, express an increased number of epidermal growth factor (EGF) receptors. Therefore, we studied the targeted delivery of the photocytotoxic compound Sn-(IV)chlorin e6 monoethylenediamine [SnCe6(ED)] to tumors that overexpress the EGF receptor. EGF was conjugated to SnCe6(ED) through a carrier, such as dextran (Dex) and human serum albumin (HSA), and the photocytotoxicity on the EGF receptor-overexpressing MDA-MB-468 breast adenocarcinoma cell line was evaluated. The photobiological activities of these EGF conjugates, of the conjugates of the photosensitizer to HSA or Dex, or of the photosensitizer alone were compared. The affinity of EGF for its receptor was substantially impaired when conjugated in EGF-Dex-SnCe6(ED), in contrast to EGF-HSA-SnCe6(ED). In corresponding results, EGF-HSA-SnCe6(ED) displayed a high photocytotoxicity (IC50, 63 nM) on MDA-MB-468 cells at a light dose of 27 kJ/m2, whereas EGF-Dex-SnCe6(ED) showed very limited photocytotoxicity. EGF-HSA-SnCe6(ED) was no longer photocytotoxic in the presence of a competing EGF concentration. The high photocytotoxicity of EGF-HSA-SnCe6(ED) was shown to be the result of a high intracellular concentration in MDA-MB-468 cells, which could be lowered dramatically by incubating the conjugate with a competing EGF concentration. In contrast, EGF-Dex-SnCe6(ED) accumulated poorly in MDA-MB-468 cells, in agreement with its low EGF receptor affinity and photocytotoxicity. EGF-HSA-SnCe6(ED) produced much more intracellular reactive oxygen species on light irradiation than EGF-Dex-SnCe6(ED). It is concluded that the photodynamic activity of the EGF-HSA conjugate of SnCe6(ED) on MDA-MB-468 breast adenocarcinoma cells is EGF specific and is much more potent than EGF-Dex-SnCe6(ED) or free SnCe6.

Topics: Adenocarcinoma; Binding, Competitive; Biological Transport; Breast Neoplasms; Cell Division; Chlorophyllides; Dextrans; Drug Synergism; Epidermal Growth Factor; ErbB Receptors; Humans; Inhibitory Concentration 50; Photochemotherapy; Porphyrins; Radiation-Sensitizing Agents; Reactive Oxygen Species; Recombinant Fusion Proteins; Serum Albumin; Substrate Specificity; Transfection; Tumor Cells, Cultured

Certain tumor cells, such as squamous carcinoma cells, express an increased number of epidermal growth factor (EGF) receptors. The goal of this study was the targeted delivery of the photocytotoxic compound Sn(IV)chlorine e6 monoethylenediamine++ (SnCe6(ED)) to tumors that overexpress the EGF receptor. Therefore EGF was conjugated to SnCe6(ED) through a carrier, such as dextran (Dex) and human serum albumin (HSA), followed by the evaluation of the photocytotoxicity on the EGF receptor overexpressing MDA-MB-468 cell line. The photobiologic activity of these conjugates was then compared to a conjugate of the photosensitizer to HSA or dextran, or to the photosensitizer alone. In contrast to EGF-HSA-SnCe6(ED), the affinity of EGF for its receptor was substantially impaired upon conjugation in EGF-Dex-SnCe6(ED). In correlation with these results, EGF-HSA-SnCe6(ED) displayed a high cytotoxicity (IC50, 63 nM) on MDA-MB-468 cells at a light dose of 27 kJ/m2, whereas EGF-Dex-SnCe6(ED) showed very limited photocytotoxicity. In the presence of a competing EGF concentration (10 microM), EGF-HSA-SnCe6(ED) was not cytotoxic anymore. The high photocytoxicity of EGF-HSA-SnCe6(ED) was shown to be a result of a high intracellular concentration in MDA-MB-468 cells, which could be lowered dramatically by incubating the conjugate with a competing EGF concentration. In contrast, EGF-Dex-SnCe6(ED) displayed very poor accumulation in MDA-MB-468 cells, in agreement with its low EGF receptor affinity and photocytoxicity. Besides, it could be demonstrated that EGF-HSA-SnCe6(ED) produced intracellularly ROS (reactive oxygen species) upon light irradiation, more than EGF-Dex-SnCe6(ED) did. It was concluded that, in contrast to EGF-Dex-SnCe6(ED) the photodynamic activity of the EGF-HSA conjugate of SnCe6(ED) on MDA-MB-468 breast adenocarcinoma cells is EGF-specific and more potent than free SnCe6(ED).

Topics: Adenocarcinoma; Animals; Binding, Competitive; Breast Neoplasms; Chlorophyllides; Dextrans; Epidermal Growth Factor; ErbB Receptors; Humans; Male; Mice; Photochemotherapy; Porphyrins; Radiation-Sensitizing Agents; Serum Albumin; Tumor Cells, Cultured

Optimizing photodynamic therapy involves attempting to increase both the absolute tumour content of photosensitizer and the selectivity between tumour and surrounding normal tissue. One reason why photodynamic therapy has not been considered suitable for treatment of metastatic tumours in the liver, is the poor selectivity of conventional photosensitizers for tumour compared to normal liver. This report details an alternative approach to increasing this selectivity by the use of antibody-targeted photosensitizers (or photoimmunoconjugates) to target intrahepatic tumours caused by human colorectal cancer cells in the nude mouse, and explores the role of molecular charge on the tumour-targeting efficiency of macromolecules. The murine monoclonal antibody 17.1A (which recognizes an antigen expressed on HT 29 cells) was used to prepare site-specific photoimmunoconjugates with the photosensitizer chlorine6. The conjugates had either a predominant cationic or anionic charge and were injected i.v. into tumour-bearing mice. Biodistribution 3 or 24 h later was measured by extraction of tissue samples and quantitation of chlorine6 content by fluorescence spectroscopy. The photoimmunoconjugates were compared to the polylysine conjugates in an attempt to define the effect of molecular charge as well as antibody targeting. The anionic 17.1A conjugate delivered more than twice as much photosensitizer to the tumour at 3 h than other species (5 times more than the cationic 17. 1A conjugate) and had a tumour:normal liver ratio of 2.5. Tumour-to-liver ratios were greater than one for most compounds at 3 h but declined at 24 h. Tumour-to-skin ratios were high (> 38) for all conjugates but not for free chlorine6. Cationic species had a high uptake in the lungs compared to anionic species. The photoimmunoconjugates show an advantage over literature reports of other photosensitizers, which can result in tumour:normal liver ratios of less than 1.

Topics: Adenocarcinoma; Animals; Anions; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Cations; Chlorophyllides; Colorectal Neoplasms; Female; HT29 Cells; Humans; Immunoconjugates; Liver Neoplasms, Experimental; Mice; Porphyrins; Radiation-Sensitizing Agents; Tissue Distribution; Xenograft Model Antitumor Assays