merocyanine-dye and Neoplasms

The reactive nature of species derived from oxygen, such as singlet oxygen and hydrogen peroxide, has been exploited in the clinical setting for targeting bacteria, viruses, and tumor cells by photodynamic excitation of a variety of chromophores. This modality, termed photodynamic therapy (PDT), is currently being used to treat some forms of cancer. However, the applicability of conventional PDT is limited due to the absolute dependence on simultaneous exposure of the target to the photoactive compound and light. In 1990, we demonstrated that the need for simultaneous exposure of the biological target to light and photosensitizer could be circumvented by prior exposure (activation) of the sensitizer molecule to light and its subsequent use as any other anti-cancer or anti-viral drug. By dint of the nature of the protocol, this process was termed preactivation. Since then, the generation of biologically active molecules in vitro by preactivation has been validated using a variety of chromophores, such as merocyanine 540, Photofrin II, and naphthalimide. Here we briefly review the role of reactive oxygen species in the photodynamic effect, and provide an explanation for the mechanism of preactivation. We propose that photo-oxidation not only provides a novel means for the generation of biologically active molecules, but could also explain, at least in part the mechanism of conventional PDT. It is likely that the light-dependent breakdown of the chromophore to generate novel active compounds, in addition to reactive oxygen species, also contributes to the photodynamic damage observed on simultaneous exposure of the chromophore and target tissue to light during PDT.-Pervaiz, S. Reactive oxygen-dependent production of novel photochemotherapeutic agents.

Topics: Animals; Caspases; Humans; Neoplasms; Oxidation-Reduction; Photochemotherapy; Photosensitizing Agents; Pyrimidinones; Reactive Oxygen Species

The pros and cons of purging of either bone marrow or peripheral blood stem cell preparations for autologous transplantation for cancer has been debated strongly over the past decade. Recent data implicating the role of minimal residual disease in autografted marrow in cancer relapse have renewed interest in this question. There is a considerable body of literature supporting the possibility that photosensitizer molecules in combination with light might provide a therapeutic window permitting selective elimination of malignant stem cells while sparing those of normal lineage. Molecules of this class are known to be taken up more actively by most malignant cells, and intracellular concentrations are critical in their cytotoxic effect when they are activated by light at an appropriate wavelength. The present paper reviews the observations made over the past decade on a variety of photosensitizers and their effects on hemopoietic progenitors.

Topics: Bone Marrow Purging; Bone Marrow Transplantation; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Hematoporphyrin Derivative; Humans; Indoles; Light; Neoplasms; Neoplastic Stem Cells; Organometallic Compounds; Photosensitizing Agents; Porphyrins; Pyrimidinones

Recent preclinical and clinical investigations indicate that phototherapy and photochemotherapy may have applications that go far beyond their "traditional" roles in the treatment of skin disorders, selected solid tumors, and neonatal hyperbilirubinemia. Bone marrow transplantation is one area that may benefit substantially from these new developments. This review focuses on new applications of phototherapy and photochemotherapy that pertain to the inactivation of tumor cells in autologous bone marrow grafts, the prevention and treatment of acute and chronic graft-versus-host disease, the prevention of transfusion-induced allosensitization and graft rejection, and the inactivation of pathogenic viruses and parasites in bone marrow grafts and blood products.

Topics: Animals; Antiviral Agents; Blood; Bone Marrow Purging; Bone Marrow Transplantation; Graft Rejection; Graft vs Host Disease; Humans; Immunization; Infection Control; Mice; Neoplasms; Neoplastic Stem Cells; Photochemotherapy; Photosensitizing Agents; Phototherapy; Pyrimidinones; Radiation-Sensitizing Agents; Transfusion Reaction

Topics: Animals; Cells; Coloring Agents; Humans; Leukemia; Neoplasms; Photolysis; Pyrimidinones; Radiation-Sensitizing Agents

Recent preclinical and clinical investigations indicate that phototherapy and photochemotherapy may have applications that go far beyond their "traditional" roles in the treatment of skin disorders, selected solid tumors, and neonatal hyperbilirubinemia. Bone marrow transplantation is one area that may benefit substantially from these new developments. This review focuses on new applications of phototherapy and photochemotherapy that pertain to the inactivation of tumor cells in autologous bone marrow grafts, the prevention and treatment of acute and chronic graft-versus-host disease, the prevention of transfusion-induced allosensitization and graft rejection, and the inactivation of pathogenic viruses and parasites in bone marrow grafts and blood products.

Topics: Animals; Antiviral Agents; Blood; Bone Marrow Purging; Bone Marrow Transplantation; Graft Rejection; Graft vs Host Disease; Humans; Immunization; Infection Control; Mice; Neoplasms; Neoplastic Stem Cells; Photochemotherapy; Photosensitizing Agents; Phototherapy; Pyrimidinones; Radiation-Sensitizing Agents; Transfusion Reaction

Multifunctional probes with high utilization rates have great value in practical applications in various fields such as cancer diagnosis and therapy. Here we have synthesized two organic molecules based on merocyanine. They can self-assemble in water to form ∼1.5 nm nanoparticles. Both of them have good application potential in fluorescent anticounterfeit printing ink and pH detection. More importantly, they have excellent mitochondrial targeting ability, intracellular red light and near-infrared dual-channel imaging ability, strong antiphotobleaching ability, and

Topics: Animals; Antineoplastic Agents; Apoptosis; Benzopyrans; Cell Line, Tumor; Fraud; Humans; Hydrogen-Ion Concentration; Indicators and Reagents; Indoles; Ink; Membrane Potential, Mitochondrial; Mice; Mitochondria; Nanoparticles; Neoplasms; Reactive Oxygen Species

γ-Glutamyl transpeptidase (GGT) is a cell-membrane-bound enzyme that is involved in various physiological and pathological processes and is regarded as a potential biomarker for many malignant tumors, precise detection of which is useful for early cancer diagnosis. Herein, a new GGT-activatable near-infrared (NIR) fluorescence imaging probe (GANP) by linking of a GGT-recognitive substrate γ-glutamate (γ-Glu) and a NIR merocyanine fluorophore (mCy-Cl) with a self-immolative linker p-aminobenzyl alcohol (PABA) is reported. GANP was stable under physiological conditions, but could be efficiently activated by GGT to generate ≈100-fold enhanced fluorescence, enabling high sensitivity (detection limit of ≈3.6 mU L

Topics: Animals; Benzopyrans; Benzyl Alcohols; Cell Line, Tumor; Female; Fluorescent Dyes; gamma-Glutamyltransferase; HCT116 Cells; Humans; Indoles; Mice; Mice, Nude; Microscopy, Fluorescence; Neoplasms; Spectroscopy, Near-Infrared; Transplantation, Heterologous

In clinic, the application of photodynamic therapy (PDT) in deep tissue is severely constrained by the limited penetration depth of visible light needed for activating the photosensitizer (PS). In this Article, a merocyanine 540 (MC540) and upconverting nanoparticle (UCN) coloaded functional polymeric liposome nanocarrier, (MC540 + UCN)/FPL, was designed and constructed successfully for solving this problem in PDT. Compared with the conventional approaches using UCNs absorbing PSs directly, the combination of UCN and polymeric liposome has unique advantages. The UCN core as a transducer can convert deep-penetrating near-infrared light to visible light for activating MC540. The functional polymeric liposome shell decorated with folate as a nanoshield can keep the UCN and MC540 stable, protect them from being attacked, and help them get into cells. The results show that (MC540 + UCN)/FPL is an individual nanosphere with an average size of 26 nm. MC540 can be activated to produce singlet oxygen successfully by upconverting fluorescence emitted from UCNs. After (MC540 + UCN)/FPL was modified with folate, the cell uptake efficiency increased obviously. More interestingly, in the PDT effect test, the (MC540 + UCN)/FPL nanocarrier further improved the inhibition effect on tumor cells by anchoring targeting folate and transactivating transduction peptide. Our data suggest that the (MC540 + UCN)/FPL nanocarrier may be a useful nanoplatform for future PDT treatment in deep-cancer therapy based on upconversion mechanism.

Topics: Cell Line, Tumor; Cells; Humans; Infrared Rays; Liposomes; Nanoparticles; Neoplasms; Photochemotherapy; Photosensitizing Agents; Polymers; Pyrimidinones

Both photoswitchable fluorescent nanoparticles and photoactivatable fluorescent proteins have been used for super-resolution far-field imaging on the nanometer scale, but the photoactivating wavelength for such photochemical events generally falls in the near-UV (NUV) region (<420 nm), which is not preferred in cellular imaging. However, using two near-IR (NIR) photons that are lower in energy, we can circumvent such problems and replace NUV single-photon excitations (e.g., 390 nm) with NIR two-photon excitations (e.g., 780 nm). Thus, we have demonstrated that alternating 780 nm NIR two-photon and 488 nm single-photon excitations induces reversible on-off fluorescence switching of immunotargeted nanoparticles in the human breast cancer cell line SK-BR-3. Herein, two-photon absorption not only caused spiropyran-merocyanine photoisomerization within the particles but also imparted red fluorescence. In comparison with single-photon NUV excitations, two-photon NIR laser excitations can potentially reduce absorption-related photodamage to living systems because cellular systems absorb much more weakly in the NIR.

Topics: Benzopyrans; Cell Line, Tumor; Fluorescence; Humans; Indoles; Nanoparticles; Neoplasms; Nitro Compounds; Photochemical Processes; Photons

The mechanism of resistance of cancer cells to the anticancer drug cisplatin is not fully understood. Using cisplatin-sensitive KB-3-1 and -resistant KCP-20 cells, we found that the resistant cells have higher membrane potential, as determined by membrane potential sensing oxonol dye. Electron spin resonance and fluorescence polarization studies revealed that the resistant cells have more "fluid" plasma membranes than the sensitive cells. Because of this observed difference in membrane "fluidity," we attempted modification of the plasma membrane fluidity by the incorporation of heptadecanoic acid into KB-3-1 and KCP-20 cell membranes. We found that such treatment resulted in increased heptadecanoic acid content and increased fluidity in the plasma membranes of both cell types, and also resulted in increased cisplatin resistance in the KCP-20 cells. This finding is in accord with our results, which showed that the cisplatin-resistant KCP-20 cells have more fluid membranes than the cisplatin-sensitive KB-3-1 cells. It remains to be determined whether the observed differences in biophysical status and/or fatty acid composition alone, or the secondary effect of these differences on the structure or function of some transmembrane protein(s), is the reason for increased cisplatin resistance.

Topics: Carcinoma; Cell Division; Cell Line, Tumor; Cell Membrane; Cisplatin; Clone Cells; Cyclic N-Oxides; Drug Resistance, Neoplasm; Fatty Acids; HeLa Cells; Humans; Isoxazoles; Membrane Fluidity; Membrane Lipids; Membrane Potentials; Membrane Proteins; Neoplasms; Potassium Channels; Pyrimidinones

The purpose of this study was to determine in a preclinical purging model, how effective crystal violet-mediated photodynamic therapy (CV-PDT) is against solid tumor and drug-resistant mutant tumor cells, and if certain limitations of CV-PDT can be overcome by using crystal violet (CV) in combination with the membrane-active photosensitizer, Merocyanine 540 (MC540). When used under conditions that preserved an adequate fraction of normal human granulocyte/macrophage progenitors (CFU-GM), CV-PDT failed to achieve meaningful reductions of DU145 prostate, H69 small cell lung cancer, and MDA-MB-435S breast cancer cells. Melphalan-resistant L1210/L-PAM1, adriamycin-resistant P388/ADR, and adriamycin-resistant HL-60/ADR leukemia cells were markedly less sensitive to CV-PDT than their wild-type counterparts, whereas cisplatin-resistant H69/CDDP cells were more sensitive than wild-type H69 cells. Sequential exposure to MC540- and CV-PDT under conditions that preserved an adequate fraction (73% and 29%, respectively) of normal CD34-positive hematopoietic stem cells and granulocyte/macrophage progenitors was highly effective against H69 (99.997% reduction) and H69/CDDP (99.999% reduction) cells, but ineffective against HL-60/ADR, MDA-MB-435S, and DU145 cells. CV thus shows only limited promise as a single-modality purging agent. However, in certain situations, clinically meaningful tumor cell depletions can be obtained by using CV in combination with a second photosensitizer such as MC540.

Topics: Animals; Bone Marrow Purging; Caspases; Cell Line, Tumor; Cell Survival; Drug Resistance, Neoplasm; Gentian Violet; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Humans; Mice; Molecular Structure; Necrosis; Neoplasms; Photochemotherapy; Photosensitizing Agents; Pyrimidinones; Receptors, Peptide

Topics: Animals; Binding Sites; Bone Marrow Purging; Bone Marrow Transplantation; Hematopoietic Stem Cells; Humans; Neoplasms; Neoplastic Stem Cells; Photochemotherapy; Photosensitizing Agents; Pyrimidinones; Transplantation, Autologous

Salicylate and several structurally analogous compounds enhance merocyanine 540 (MC540)-photosensitized killing of leukemia cells (M. A. Anderson, B. Kalyanaraman, and J. B. Feix, Cancer Res., 53: 806-809, 1993). In this work, we show that salicylic acid enhances the binding of MC540 prior to illumination, as well as the light-stimulated uptake of MC540 by target L1210 murine and K562 human leukemia cells. Acetylsalicylic acid, 2,3- and 2,5-dihydroxybenzoic acids, and sodium benzoate also enhance MC540 uptake. The irradiation dose responses for loss of cell survival and enhanced MC540 uptake are well correlated, both being shifted to earlier time points in the presence of salicylate. Salicylic acid also enhanced photodynamic cell killing of A549 lung carcinoma and NIH:OVCAR-3 ovarian carcinoma cells, two cell types which are relatively resistant to MC540-mediated photosensitization. Cellular uptake of the anionic, potential-sensitive oxonol dye, bis-(1,3-dibutylbarbituric acid)-trimethine oxonol, is also increased by salicylate in a dose-dependent fashion. In contrast, cellular uptake of the cationic cyanine dye, 3,3'-dihexyloxacarbocyanine, is unaffected by salicylate. These studies suggest that increased uptake of MC540 is the basis of salicylate enhancement and that changes in plasma membrane potentials may play a mechanistic role in the potentiation of MC540 binding and cell killing.

Topics: Animals; Benzoates; Benzoic Acid; Cell Survival; Drug Screening Assays, Antitumor; Drug Synergism; Fluorescence; Humans; Leukemia; Leukemia L1210; Mice; Neoplasms; Photochemotherapy; Photosensitizing Agents; Pyrimidinones; Salicylates; Salicylic Acid

Many new photosensitizers and laser wavelengths are being tested to improve photodynamic therapy by enhancing specific tumor uptake and/or retention, lowering systemic toxicity, and increasing laser tissue penetration. In this study the potential synergistic effects of rhodamine-123 (Rh-123) and merocyanine-540 (MC-540) sensitization of human tumor cell lines after laser exposure were explored. In a first series of experiments, the kinetics of uptake of Rh-123 and M-540 were tested on three human leukemia cell lines (K562, RAJI, 729HF2), P3 squamous carcinoma, and M26 melanoma. Our results demonstrate a clear difference in the rate and amount of uptake of MC-540 (K562 > P3 > RAJI > 729HF2 > M26) and Rh-123 (P3 > RAJI > 729HF2 > K562 > M26) by these cell lines. In a second series of experiments, M26 tumor cells were sensitized with either Rh-123 (1 microgram/ml) or with MC-540 (20 micrograms/ml) alone or with a combination of the two dyes for 60 minutes, then exposed to the argon (514.5 nm) laser at nonthermal energy levels. Our results demonstrate a significant enhancement of the tumoricidal effects of the laser on M26 carcinoma cells after sensitization with both dyes together (MC-540 and Rh-123) when compared to each dye alone. As with combination antibiotherapy, the synergistic effects of two laser dyes that have different intracellular targeting sites appear to enhance tumoricidal effects significantly after exposure to a matching laser wavelength. The data provide evidence for effective laser phototherapy by dye synergy.

Topics: Antimetabolites, Antineoplastic; Burkitt Lymphoma; Carcinoma, Squamous Cell; Cell Survival; Drug Synergism; Fluorescent Dyes; Hot Temperature; Humans; Laser Therapy; Leukemia, B-Cell; Leukemia, Erythroblastic, Acute; Lung Neoplasms; Melanoma; Neoplasms; Photochemotherapy; Photosensitizing Agents; Pyrimidinones; Radiation Dosage; Rhodamine 123; Rhodamines; Tumor Cells, Cultured

Merocyanine 540 (MC 540) is a photosensitizing dye that has been used in a phase I clinical trial for the purging of leukemia and lymphoma cells from autologous bone marrow grafts. In this paper we examine the role of plasma membrane negative charge, plasma membrane fluidity, and plasma membrane hydrophobicity in the regulation of a cell's susceptibility to MC 540-sensitized photoirradiation. Among solid tumor cells, we found an inverse correlation between surface electronegativity, affinity for dye molecules, and susceptibility to MC 540-sensitized photoinactivation. That is, the least electronegative cells bound the highest amount of dye and were the most susceptible to dye-sensitized photoirradiation. By contrast, no such correlations were found among leukemia/lymphoma cells. This suggested that dye binding and susceptibility to MC 540-mediated photodynamic damages are regulated differently in hematopoietic/lymphopoietic and solid tumor cells.

Topics: Bone Marrow; Bone Marrow Cells; Cell Membrane; Cell Separation; Humans; Leukemia; Light; Lymphoma; Membrane Fluidity; Neoplasms; Neuraminidase; Pyrimidinones; Radiation-Sensitizing Agents; Solubility; Surface Properties; Trypsin; Tumor Cells, Cultured

MC540-mediated photolysis has several features that make it potentially attractive as a clinical purging procedure. (1) The experience with experimental tumors suggests that MC540-mediated photolysis is effective against a broad range of leukemias and solid tumors, including drug-resistant tumors (Sieber et al., 1984b). Drug-resistant tumor cells are likely to occur in heavily pretreated patients. (2) MC540-mediated photolysis is not cell-cycle dependent (Manna and Sieber, 1985). It kills both resting and cycling cells. In this regard, MC540-mediated photolysis is a valuable complement to cell-cycle specific cytotoxic drugs. (3) There is a large differential in sensitivity between normal pluripotent hematopoietic stem cells and leukemia and neuroblastoma cells. (4) The mechanism of action of MC540-mediated photolysis is different from that of lectins, antibodies and most cytotoxic drugs. MC540 binds to the lipid portion of the plasma membrane and membrane lipids are probably a primary target of the toxic photoproducts. Antibodies and lectins react with proteins and carbohydrates and most drugs have intracellular targets (e.g., nuclear DNA). We would therefore expect little cross-resistance if MC540-mediated photolysis were used in combination with other purging procedures.(5) The small amounts of dye that remain associated with the marrow graft and are infused into the patient are approximately 100,000-fold less than the LD(10) (in mice) and therefore unlikely to cause any harm. The outcome of the first clinical application of the technique supports this view (Sieber et al., 1986c). A better understanding of the underlying molecular mechanisms will undoubtedly lead to more effective applications of the technique and perhaps to the identification of more potent analogs of MC540.

Topics: Bone Marrow; Bone Marrow Transplantation; Humans; Neoplasms; Photolysis; Pyrimidinones; Radiation-Sensitizing Agents; Transplantation, Autologous

Topics: Animals; Bone Marrow Transplantation; Graft vs Host Disease; Hematopoietic Stem Cells; Humans; Leukemia; Light; Neoplasms; Pyrimidinones; Transplantation, Autologous