Immunocytochemical studies on the nuclear ubiquitous casein and cyclin-dependent kinases substrate following 5-aminolevulinicacid-mediated photodynamic therapy on MCF-7 cells.

BACKGROUND: Recent data indicates that nuclear ubiquitous casein and cyclin-dependent kinases substrate (NUCKS) may play role in tumor growth. In present study authors examined whether photodynamic therapy with 5-aminolevulinic acid (5-ALA) induces NUCKS expression in breast cancer cell line, MCF-7. METHODS: In the experiment concentration of 5-ALA was 6.5mM. Excitation wavelength was 630 ± 20 nm, total light dose of light 5 or 10 J/cm(2) and irradiance 60 mW/cm(2) was used. Cells were collected at established time points and Western blot and immunocytochemical studies were performed using antibody against NUCKS. RESULTS: Studies proved strong cytotoxic effects in cells following PDT with 6.5mM of precursor and 10 J/cm(2). Western blot analysis revealed the strongest expression of NUCKS at 7h after PDT. At next time points, 18 and 24h, expression of NUCKS decreased and became similar to that of control group. Further immunocytochemical studies showed very strong expression of NUCKS following PDT with 5-ALA and light irradiation of 5 J/cm(2). Early, at 0 h, that expression was predominantly seen in nuclei, while at 7h expression of NUCKS was observed in disseminated manner within entire cells in both nuclei and cytoplasm, with prevalence of cytoplasmic staining. CONCLUSIONS: Authors suggest that NUCKS is involved in cellular responses following PDT, and since parallel induction of NUCKS and proapoptotic marker Bax and inhibition of anti-apoptotic Bcl-2 was observed, this protein might also be involved in induction of apoptosis following PDT.

In vitro and in vivo matrix metalloproteinase expression after photodynamic therapy with a liposomal formulation of aminolevulinic acid and its methyl ester.

Photodynamic therapy (PDT) is a well-known method for the treatment of malignant tumors, and its principles have been well established over the past 30 years. This therapy involves the application of a chemical called a photosensitizer and its subsequent excitation with light at the appropriate wavelength and energy. Topical photodynamic therapy with aminolevulinic acid (5-ALA) is an alternative therapy for many malignant processes, including nonmelanoma skin cancers such as basal-cell carcinoma (BCC). Our novel approach for this study was to use a liposomal formulation of 5-ALA and its methyl ester (commercially available as metvix) both in vitro and in vivo, and to check whether the liposome-entrapped precursors of photosensitizers can induce the expression of metalloproteinases (MMPs) in animal tumor cells and in other tissues from tumor-bearing rats and in selected cell lines in vitro. We also checked whether the application of tissue inhibitors of matrix metalloproteinases (TIMPs) has any effect on MMPs in the above-mentioned experimental models, and if they can cause complete inhibition of MMP expression. Immunohistochemical studies revealed that after the PDT, the intensity of expression of MMPs in healthy animals was very low and seen in single cells only. After the PDT in tumor-bearing rats, MMP-3 was expressed in the tumor cells with the highest intensity of staining in the tissues directly adjacent to the tumors, while MMP-2 and -9 were not found. In the control groups, there was no observed expression of MMPs. In vitro studies showed that MMP-3 was expressed in MCF-7 cells after PDT, but MMP-9 was not observed and MMP-2 was only seen in single cases. Our studies confirmed that the application of an MMP-3 inhibitor may block an induction of MMP-3 expression which had previously been initiated by PDT. The preliminary data obtained from cancer patients revealed that new precursors are effective in terms of PDT, and that using MMP inhibitors should be considered as a potential enhancing factor in clinical PDT.

A brief history of photodynamic therapy in Wroclaw.

A brief history of photodynamic therapy in Wroclaw was presented in this paper.

Pretreatment of plantar warts with azone enhances the effect of 5-aminolevulinic acid photodynamic therapy.

5-Aminolevulinic acid (5-ALA) is a well characterized precursor in the synthesis of various endogenous porphyrins used in photodynamic therapy (PDT). It is most often administered topically into a tumor which is then irradiated with visible light at established wavelength to sensitize porphyrins accumulated therein. Our main aim in the present study was to increase the penetration of 5-ALA through the altered skin by application of 3% azone (1-dodecyl-azepan-2-one) before the application of 20% 5-ALA in patients with plantar warts: mosaic warts (MW) and myrmecia (MY). We also used 20% 5-ALA only to treat warts in other patients. We compared the therapeutic and cosmetic effects of the two treatment modalities. The lesions treated with modification of 5-ALA-PDT by pretreatment with azone responded with better effectiveness. In 18 patients subjected to 5-ALA-PDT plus 3% azone, we observed 66.7% complete response of MW and 100% of MY following PDT repeated two or three times; whereas in other 18 patients treated with 5-ALA-PDT alone, we observed only 37.5% complete response of MW and 70% of MY. These results provide evidence that the pretreatment with azone should be considered as the step that enhances 5-ALA penetration in tissues and thus increases the effectiveness of applied PDT.

Enhancement of photodynamic therapy by use of aminolevulinic acid/glycolic acid drug mixture.

5-aminolevulinic acid (5-ALA) is a precursor in synthesis of endogenous porphyrins used to sensitize tumor tissues in photodynamic therapy (PDT). It is administered topically into a tumor which after the certain time, required for porphyrins to accumulate, is irradiated with visible light from the proper source at established wavelength. Our main aim in the present study was to increase the penetration of 5-ALA through the skin and other tissues by addition of glycolic acid (GA) to 5-ALA on cell lines in vitro and on animals. We also applied 5-ALA ointment with glycolic acid to patients suffering from squamous cell carcinoma (SCC). In our study, we used 5-ALA, dimethyl sulfoxide (DMSO), ethylenediaminetetraacetic acid, disodium salt (EDTA) and GA together in one formulation (5-ALA-GA) on eucerin support. We compared both therapeutic and cosmetic effects in 5-ALA-GA-PDT and in control group of patients. Our results showed that modification of 5-ALA ointment by addition of 5% GA caused that the treated lesions responded with rapid regression. In 12 patients with single lesions of SCC type subjected to 5-ALA-GA-PDT, we observed 100% regression of tumors following single or repeated two-three times PDT. In vitro and in vivo in animals total porphyrin levels after addition of 5% GA increased significantly (P<0.01). These results provide evidence that addition of glycolic acid should be considered as the agent which enhances 5-ALA penetration in tissues and thus increases the effectiveness of photodynamic therapy.