Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0684249 (lung carcinoma)
 23,830 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum amyloid P component (SAP) is known as a prototypic acute phase reactant in the mouse and the protein that binds to dying cells securing their swift disposal by phagocytes. Treatment of solid tumors by photodynamic therapy (PDT) triggers SAP production in the liver of host mice, its release in the circulation and accumulation in PDT-targeted lesions. In the present study, mouse Lewis lung carcinoma (LLC) cells treated in vitro by PDT are shown to upregulate their gene encoding SAP. This effect was manifested following PDT treatment mediated by various types of photosensitizers (Photofrin, BPD, mTHPC, ALA). Generated SAP protein was not detected in tissue supernatants but remained localized to producing PDT-treated cells. The upregulation of SAP gene was observed also in untreated IC-21 macrophages after they were co-incubated for 4 h with PDT-treated LLC cells. Based on these findings, SAP that accumulates in PDT-treated tumors may originate from both systemic sources (released from the liver as acute phase reactant) and local sources; the latter could include tumor cells directly sustaining PDT injury and macrophages invading the tumor that become stimulated by signals from these affected tumor cells. Since SAP gene upregulation in LLC cells increased with the lethality of PDT dose used for their treatment, we propose that cells sensing they are inflicted with mortal injury can turn on molecular programs insuring not only that they die an innocuous form of death (apoptosis) but also that once they are dead their elimination is (facilitated by SAP) swift and efficient.
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PMID:Dying cells program their expedient disposal: serum amyloid P component upregulation in vivo and in vitro induced by photodynamic therapy of cancer. 1804 83

In this study we proved the efficiency of the fluorimetric detection of a minimum number of malignant cells ex vivo. The goal of this work was to investigate whether the combination of photodynamic diagnosis (PDD) with oral brush biopsy might become a suitable chair-side tool to detect early oral carcinoma. Small numbers (100-500) of established human tumour cells-small cell lung carcinoma (OAT 75), transitional cell carcinoma of the bladder (SW1710) and human embryonic kidney cells (HEK293)-were incubated with 2 mM 5-aminolaevulinic acid (5-ALA). In addition, 50 brush biopsies from volunteers were prepared. After 2 h and 3 h of incubation, all samples were investigated by spectrofluorometry. Measurements were performed in capillaries. For excitation (405 nm) and detection of fluorescence spectra, a fibre microprobe-spectrofluorometer system (fibre 400 microm) was used. A minimum of 100 malignant cells and 3 h of incubation with ALA were needed to detect a typical spectrum for protoporphyrin IX (PPIX). Some epithelial samples from brush biopsy showed strong (bacteria related) PPIX autofluorescence, which increased after the addition of 5-ALA. From the testing of various antibiotics and antiseptics it emerged that 0.4 mM chlorhexidine strongly reduced fluorescence in brush biopsies from healthy volunteers, whereas the fluorescence signal of established cancer cell lines decreased only a little. The experiments revealed that, by means of an optical microprobe, very few cancer cells (100) can be detected. The addition of chlorhexidine before the incubation of brush biopsies with 5-ALA increases the reliability of the test by largely reducing the autofluorescence signal due to the presence of bacteria. Chair-side diagnostics of epithelial carcinoma seem feasible.
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PMID:Ex vivo photodynamic diagnosis to detect malignant cells in oral brush biopsies. 1966 85

5-aminolevulinc acid (5-ALA)-based photodynamic therapy (PDT) and photodiagnosis (PD) present many advantages over treatments with conventional photosensitizers (PS). It offers great tumor specificity, reduced photosensitivity reactions caused by PS accumulation in non-targeted tissues and also inherent PS metabolism into endogenous non-fluorescent heme. However, chemical instability, low bioavailability and poor pharmacokinetic profile limit systemic efficacy of 5-ALA. Here, we present a comprehensive in vitro evaluation of novel phosphatase-sensitive prodrugs of 5-ALA. These prodrugs are designed to be activated by ubiquitously expressed phosphatases with much improved chemical stability and reduced acute toxicity profile. PpIX kinetic measurements and flow cytometry show accumulation of PpIX upon incubation with phosphatase-sensitive prodrugs in PC3 human prostate cell cancer, MCF7 breast adenocarcinoma, U87MG glioblastoma, T24 bladder cancer and A549 lung carcinoma cells. They revealed a different fluorescence kinetics and dose-response curves for the different types of 5-ALA prodrugs. These experiments have allowed us to identify the most promising cancer cell types for phospho- 5-ALA prodrugs. Confocal fluorescence microscopy provided further evidence of fluorescent protoporphyrin IX accumulation and sub-cellular localisation. These findings, together with the low toxicity profile of phosphatase-sensitive prodrugs of 5-ALA and good response to PDT provide solid basis for future translational development in PC3, MCF7 and U87MG cancer types.
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PMID:Activity of phosphatase-sensitive 5-aminolevulinic acid prodrugs in cancer cell lines. 2847 23