Effect of photodynamic therapy mediated by hematoporphyrin derivatives on small cell lung cancer H446 cells and bronchial epithelial BEAS-2B cells.

To investigate the effects of photodynamic therapy (PDT) mediated by hematoporphyrin derivatives (HPD) on the proliferation of small cell lung cancer H446 cells and bronchial epithelial BEAS-2B cells. H446 cells and BEAS-2B cells were cultured in vitro with different concentrations of HPD(0, 5, 10, 12, 15, 20 µg/mL) for 4 h, and then irradiated with 630 nm laser with different energy densities (0, 25, 50, 75, 100 mW/cm2). Cell viability of H446 cells and BEAS-2B cells were detected by CCK8 assay. The cell apoptosis was observed with Annexin V-FTTC/PI double staining and Hoechst 33258. The RT-PCR examination was applied to detect the transcriptional changes of the mRNA of Bax、Bcl-2, and Caspase-9. The results of CCK8 showed that when the HPD was 15 µg/mL and the laser power density reached 50 mW/cm2, the cell viability was significantly decreased compared with the black control group. Hoechst 33258 staining showed that with the increase of HPD concentration, the cell density was reduced, and apoptotic cells increased. Flow cytometry assay revealed that the apoptotic rates of the HPD-PDT group of H446 cells and BEAS-2B cells were significantly different from those of the blank control group. The RT-PCR examination showed that the expression levels of Bax and Caspase-9 mRNA in the HPD-PDT group were up-regulated, while the expression levels of Bcl-2 mRNA were down-regulated significantly. HPD-PDT can inhibit H446 cells and BEAS-2B cells growth. The mechanism may be related to up-regulating the expression levels of Bax and Caspase-9 mRNA and down-regulating the expression levels of Bcl-2 mRNA.

The upregulation of immune checkpoints after photodynamic therapy reducing immune effect for treating breast cancer.

The immune effect induced by photodynamic therapy (PDT) has a limited effect on breast tumor. This study hypothesized that suppressive immune checkpoints on T cells might upregulate after PDT, which may reduce the antitumor effect of PDT for treating breast tumor. This study explored the alteration of immune checkpoint for the first time. A bilateral subcutaneous transplanted breast tumor mice model was established, and right tumors imitated primary tumors, and left tumors imitated distant tumors. Primary tumors were treated with PDT mediated by hematoporphyrin derivatives (HpD-PDT). Costimulatory molecules (ICOS, OX40, and 4-1BB) and immune checkpoints (PD1, LAG-3, CTLA-4, TIM-3, TIGIT) on tumor infiltrating T cells after HpD-PDT were analyzed by flow cytometry. Antitumor and immune effects were also assessed after HpD-PDT combined with anti-PD1 and LAG-3 antibodies. Primary tumors were suppressed, but distant tumors could not be inhibited after HpD-PDT. The number of T cells was increased, but function did not enhance after HpD-PDT. Additionally, costimulatory molecules (ICOS, OX40, and 4-1BB) were not elevated, but the suppressive immune checkpoints on tumor infiltrating T cells were upregulated after HpD-PDT. Notably, PD1+ LAG-3+ CD4+ T and PD1+ LAG-3+ CD8+ T cells were significantly increased. When PD1 and LAG-3 blockade combined with HpD-PDT, both primary and distant tumors were significantly suppressed, and antitumor immune effects were significantly enhanced. HpD-PDT could upregulate the PD1+ LAG-3+ CD4+ T and PD1+ LAG-3+ CD8+ T cells. Dual blockade of PD1 and LAG-3 immune checkpoints can enhance the antitumor effect of HpD-PDT.

The study of effect and mechanism of 630-nm laser on human lung adenocarcinoma cell xenograft model in nude mice mediated by hematoporphyrin derivatives.

To investigate the effect and mechanism of 630-nm laser on human lung adenocarcinoma cell xenograft model in nude mice mediated by hematoporphyrin derivatives (HPD) and provide theoretical basis for clinical photodynamic therapy (PDT). Human lung adenocarcinoma cell xenograft model in nude mice was established and randomly divided into four groups: control group, pure photosensitizer group, pure irradiation group, and photodynamic treatment group. The tumor volume growth was compared, and the tumor growth inhibition rate was calculated. HE staining was used for routine pathological observation of tumor sections, and gross conditions of cells, interstitium, and blood vessels in several groups of tumor tissues were observed. TUNEL staining was used to observe and compare the apoptosis induced by photodynamic therapy. Real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression level of angiogenesis-related factors VEGF, HIF-1α and apoptosis-related factors Bax and Bcl-2 mRNA in the transplanted tumor tissues. Western blot was employed to detect the expression of angiogenesis-related proteins VEGF, HIF-1α and apoptosis-related proteins Bax, Caspase-3, and Bcl-2. Compared with the other three groups, the tumor growth inhibition rate of the photodynamic treatment group was significantly increased and the difference was statistically significant (P < 0.05). HE staining showed that the animal model of lung adenocarcinoma A549 was successfully established. TUNEL staining revealed that more apoptotic cells were found in the photodynamic treatment group, and the apoptosis index was calculated. Compared with the other three groups, the difference was statistically significant (P < 0.05). RT-PCR results showed that compared with the other three groups, the mRNA expressions of VEGF, HIF-1α, and Bcl-2 in the photodynamic treatment group decreased, while the expression of Bax mRNA increased(P < 0.05), and the differences were statistically significant. Western blot results showed that protein expressions of VEGF, HIF-1α, and Bcl-2 decreased in the photodynamic treatment group, while protein expression level of Bax and Caspase-3 increased (P < 0.05), indicating statistically significant differences. The 630-nm laser mediated by hematoporphyrin derivatives can significantly inhibit the growth of human lung adenocarcinoma xenograft tumor in nude mice, the mechanism of which is related to the inhibition of tumor angiogenesis by down-regulating VEGF and HIF-1α gene expression, and the promotion of tumor apoptosis by up-regulating Bax, Caspase-3, and down-regulating Bcl-2 gene expression.

The study of killing effect and inducing apoptosis of 630-nm laser on lung adenocarcinoma A549 cells mediated by hematoporphyrin derivatives in vitro.

To investigate the killing effect and inducing apoptosis of 630-nm laser mediated by hematoporphyrin derivatives (HPD) on human lung adenocarcinoma A549 cells. The human lung adenocarcinoma A549 cells were incubated at random with different concentrations of HPD (5, 10, 12, 15, 20 µg/ml) for 4 h and then illuminated by 630-nm laser with different energy densities (25, 50, 75, 100 mW/cm2). And, meanwhile, the simple photosensitizer group, laser irradiation group, and blank control group were established. Then, CCK8, Hoechst 33258 staining, RT-PCR, and Western blot were employed. HPD-PDT proved no killing effect on the lung adenocarcinoma A549 cells with photosensitizer or laser irradiation alone. With the combination, the killing effect was obvious. CCK8 showed that the A549 cell viability in 15 µg/ml and 20 µg/ml HPD group as well as 50 mW/cm2, 75 mW/cm2, and 100 mW/cm2 power density group decreased significantly compared with the control group. Hoechst 33258 staining showed that with the increase of HPD concentration, the cells presented chromatin fixation and hyperchromatic nuclei. The Annexin V-FITC/PI double staining was used to detect the apoptosis rate, and the difference was statistically significant. RT-PCR and Western blot showed that the expression of Caspase-3 and Bax were significantly up-regulated. However, the Bcl-2 and Survivin were significantly down-regulated in the HPD-PDT group, while those of the other three groups showed no significant changes. HPD-PDT has a significant effect on A549 cells. The mechanism of action may be related to the upregulation of the expression of Caspase-3, Bax, and downregulation of the expression of Bcl-2 and Survivin.

Identification of the targets of hematoporphyrin derivative in lung adenocarcinoma using integrated network analysis.

BACKGROUND: Hematoporphyrin derivative (HPD) has a sensibilization effect in lung adenocarcinoma. This study was conducted to identify the target genes of HPD in lung adenocarcinoma. METHODS: RNA sequencing was performed using the lung adenocarcinoma cell line A549 after no treatment or treatment with X-ray or X-ray + HPD. The differentially expressed genes (DEGs) were screened using Mfuzz package by noise-robust soft clustering analysis. Enrichment analysis was carried out using "BioCloud" online tool. Protein-protein interaction (PPI) network and module analyses were performed using Cytoscape software. Using WebGestalt tool and integrated transcription factor platform (ITFP), microRNA target and transcription factor (TF) target pairs were separately predicted. An integrated regulatory network was visualized with Cytoscape software. RESULTS: A total of 815 DEGs in the gene set G1 (continuously dysregulated genes along with changes in processing conditions [untreated-treated with X-ray-X-ray + treated with HPD]) and 464 DEGs in the gene set G2 (significantly dysregulated between X-ray + HPD-treated group and untreated/X-ray-treated group) were screened. The significant module identified from the PPI network for gene set G1 showed that ribosomal protein L3 (RPL3) gene could interact with heat shock protein 90 kDa alpha, class A member 1 (HSP90AA1). TFs AAA domain containing 2 (ATAD2) and protein inhibitor of activated STAT 1 (PIAS1) were separately predicted for the genes in gene set G1 and G2, respectively. In the integrated network for gene set G2, ubiquitin-specific peptidase 25 (USP25) was targeted by miR-200b, miR-200c, and miR-429. CONCLUSION: RPL3, HSP90AA1, ATAD2, and PIAS1 as well as USP25, which is targeted by miR-200b, miR-200c, and miR-429, may be the potential targets of HPD in lung adenocarcinoma.

Imbalance of Ca2+ and K+ fluxes in C6 glioma cells after PDT measured with scanning ion-selective electrode technique.

Photodynamic therapy (PDT) possesses the capacity to lead to death of C6 glioma in vitro and in vivo. The purpose of this study was to investigate whether Ca(2+) and K(+) homeostasis of C6 glioma cells were affected by PDT. C6 glioma cells were randomly divided into five groups: control group, Hematoporphyrin derivative (HpD) group (10 mg/l, without irradiation), PDT group (HpD 10 mg/l + irradiation), PDT&6-Cyano-7-nitroquinoxaline-2,3-dione (CNQX) group (HpD 10 mg/l + CNQX 50 mol/l + irradiation), and HpD&CNQX group (HpD 10 mg/l + CNQX 50 mol/l, without irradiation). Glioma cells in PDT and PDT&CNQX group were subjected to PDT. Cells in PDT&CNQX group were administered α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor antagonist CNQX prior to PDT on C6 glioma cells. The changes of Ca(2+) and K(+) fluxes were studied by using a non-invasive scanning ion-selective electrode technique (SIET). Morphology of C6 cells was observed with optical microscopy. PDT induced Ca(2+) influx and K(+) efflux significantly, which resulted in death of C6 cells. When AMPA glutamate receptor antagonist CNQX was applied, Ca(2+) influx and K(+) efflux were partly blocked up and viability of C6 cells increased. These results indicate that Ca(2+) influx and K(+) efflux may correlate with the treatment effects of PDT on C6 glioma cells.

Sequence-dependent effects of hematoporphyrin derivatives (HPD) photodynamic therapy and cisplatin on lung adenocarcinoma cells.

BACKGROUND: Hematoporphyrin derivatives (HPD)-Photodynamic therapy (PDT) in combination with cisplatin (DDP) is an effective anticancer strategy. However, whether the order of combination affects efficacy has not been studied. METHODS: The human lung adenocarcinoma (LUAD) A549 cells were used as the study subjects. After A549 cells were treated with a single medication (PDT/DDP) or a sequential combination (PDT + DDP / DDP + PDT), the cell viability was assayed using the cell counting kit-8 method. Hoechst staining, Annexin-V/propidium iodide (PI) double staining, western blotting, and a real-time quantitative polymerase chain reaction (RT-qPCR) were performed to examine the mechanisms behind the combined effects. RESULTS: A synergistic impact between HPD-PDT and DDP was found. The cell viability in the PDT+DDP group was significantly lower than in the DDP+PDT group. A significant apoptotic profile and a high apoptotic rate were seen in the PDT + DDP group. The western blot showed that the expression levels of Bcl2-associated x(Bax) and cleaved-poly ADP-ribose polymerase (PARP) increased, and those of B-cell lymphoma-2 (Bcl-2) and Caspase-9 decreased in the PDT + DDP group. At the same time, the RT-qPCR revealed the upregulation of Bax and PARP mRNA and the downregulation of Bcl-2 and Caspase-9 mRNA. CONCLUSION: The order of the combination therapy (PDT + DDP / DDP + PDT) was important. The HPD-PDT followed by DDP significantly inhibited LUAD cell viability, which may be related to the mitochondrial apoptotic pathway.

Safety assessment of oral photodynamic therapy in rats.

Photodynamic therapy (PDT) is based on the synergism of a photosensitive drug (a photosensitizer) and visible light to destroy target cells (e.g., malignant, premalignant, or bacterial cells). The aim of this study was to investigate the response of normal rat tongue mucosa to PDT following the topical application of hematoporphyrin derivative (Photogem®), Photodithazine®, methylene blue (MB), and poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with MB. One hundred and thirty three rats were randomly divided in various groups: the PDT groups were treated with the photosensitizers for 10 min followed by exposure to red light. Those in control groups received neither photosensitizer nor light, and they were subjected to light exposure alone or to photosensitizer alone. Fluorescent signals were obtained from tongue tissue immediately after the topical application of photosensitizers and 24 h following PDT. Histological changes were evaluated at baseline and at 1, 3, 7, and 15 days post-PDT treatment. Fluorescence was detected immediately after the application of the photosensitizers, but not 24 h following PDT. Histology revealed intact mucosa in all experimental groups at all evaluation time points. The results suggest that there is a therapeutic window where PDT with Photogem®, Photodithazine®, MB, and MB-loaded PLGA nanoparticles could safely target oral pathogenic bacteria without damaging normal oral tissue.

Photodynamic therapy for the treatment of induced mammary tumor in rats.

The objective of this work was to evaluate photodynamic therapy (PDT) by using a hematoporphyrin derivative as a photosensitizer and light-emitting diodes (LEDs) as light source in induced mammary tumors of Sprague-Dawley (SD) rats. Twenty SD rats with mammary tumors induced by DMBA were used. Animals were divided into four groups: control (G1), PDT only (G2), surgical removal of tumor (G3), and submitted to PDT immediately after surgical removal of tumor (G4). Tumors were measured over 6 weeks. Lesions and surgical were LEDs lighted up (200 J/cm(2) dose). The light distribution in vivo study used two additional animals without mammary tumors. In the control group, the average growth of tumor diameter was approximately 0.40 cm/week. While for PDT group, a growth of less than 0.15 cm/week was observed, suggesting significant delay in tumor growth. Therefore, only partial irradiation of the tumors occurred with a reduction in development, but without elimination. Animals in G4 had no tumor recurrence during the 12 weeks, after chemical induction, when compared with G3 animals that showed 60 % recurrence rate after 12 weeks of chemical induction. PDT used in the experimental model of mammary tumor as a single therapy was effective in reducing tumor development, so the surgery associated with PDT is a safe and efficient destruction of residual tumor, preventing recurrence of the tumor.

Two Molecular Weights Holothurian Glycosaminoglycan and Hematoporphyrin Derivative-Photodynamic Therapy Inhibit Proliferation and Promote Apoptosis of Human Lung Adenocarcinoma Cells.

Holothurian glycosaminoglycan (hGAG) is extracted from the body wall of the sea cucumber, and previous studies have shown many unique bioactivities of hGAG, including antitumor, anti-angiogenesis, anti coagulation, anti thrombosis, anti-inflammation, antidiabetic effect, antivirus, and immune regulation. The effects of 3W and 5W molecular weights hGAG with hematoporphyrin derivative-photodynamic therapy (HPD-PDT) on lung cancer were investigated. Human lung adenocarcinoma A549 cells were divided into 6 groups: control group, 3W molecular weight hGAG group, 5W molecular weight hGAG group, HPD-PDT group, 3W molecular weight hGAG + HPD-PDT group, and 5W molecular weight hGAG + HPD-PDT group. Cell morphology was observed under inverted phase contrast microscope. Cell proliferative activity was detected by CCK8 and cell apoptosis was assayed by Hoechst33258 staining and flow cytometry. The results showed that two different molecular weights hGAG could inhibit proliferation, promote apoptosis rates of A549 cells, and enhance the sensitivity of A549 cells to HPD-PDT. The combined use of hGAG and HPD-PDT has synergistic inhibitory effects on A549 cells, and the effects of 3W molecular weight hGAG are better than that of 5W molecular weight hGAG.

Photodynamic therapy with hematoporphyrin derivative for recurrent plantar cutaneous squamous cell carcinoma: A case report.

Cutaneous squamous cell carcinoma (cSCC) is a prevalent malignant tumor typically treated through surgical removal. However, when the lesion is situated in specific areas like the hands, feet, or lips, particularly if it's sizable, surgical interventions can adversely impact appearance and function. In such cases, non-surgical treatments are preferable to preserve both aesthetics and functionality. We present a case of recurrent cSCC on the plantar region post-surgery. Given the extensive lesion area, deep infiltration, and the patient's reliance on foot function, hematoporphyrin derivative-photodynamic therapy (HpD-PDT) was chosen over traditional surgery. The lesion was successfully treated, and while a minor recurrence was observed after 20 months, it was localized and amenable to non-surgical intervention. We posit that HpD-PDT is a viable treatment for cSCC, especially in unique locations, with extensive lesions, and postoperative recurrence.

Light dose effect of photodynamic therapy on growth inhibition and apoptosis induction in non-small cell lung cancer: A study in nude mouse model.

BACKGROUND: Photodynamic therapy (PDT) is receiving increasing attention in treating non-small cell lung cancer (NSCLC) worldwide, but in clinical practice, the relationship between treatment effect and PDT light dose in NSCLC remains unclear. Therefore, we aimed to determine the optimal light dose for PDT by exploring molecular biomarkers and evaluating tumor growth data. METHODS: We applied bioinformatics to identify promising genes and pathways in NSCLC and PDT. Then, the human lung adenocarcinoma cell line A549-bearing BALB/c nude mice were treated with hematoporphyrin derivative (HPD, 3 mg/kg) that is currently used widely for lung cancer treatment in the world even with photosensitization issues. After 48 h, tumor-bearing mice were irradiated superficially at doses of 100, 200, 300, 400, and 500 J/cm2. The tumor growth data and apoptotic molecules were assessed and calculated. RESULTS: Bioinformatics results indicated that the apoptosis pathway was significantly enriched and caspase 3 was the most promising biomarker on prognosis in NSCLC-PDT. Compared to the untreated group, there was no difference in the relative tumor volume (RTV) of the 100 J/cm2 group, while the RTV of the other treatment groups (200-500 J/cm2) was significantly lower. In the 100 J/cm2 group, there were significant differences in the complete remission (CR, 0 %) and the percentage of tumor growth inhibition rate (TGI%) over 75 % (20 %) compared with the other treatment groups, especially the 300 and 400 J/cm2 groups (CR 70 %; TGI% 90 %). In the 300 and 400 J/cm2 groups, the expression of caspase 3, cleaved-caspase 3, PARP1, and Bax was increased significantly, while Bcl-2 expression was significantly lower. CONCLUSIONS: Moderate doses of PDT (300 or 400 J/cm2) are more effective than low (100 or 200 J/cm2) or high doses (500 J/cm2) in the A549 tumor-bearing mice model. Since the A549 tumor is more akin to human tumors in pathological behavior, these experimental data may contribute to improving HPD-PDT illumination protocols for favorable clinical outcomes.

Efficacy of hematoporphyrin injection (HpD) photodynamic therapy in the treatment of widespread extramammary Paget's disease.

Photodynamic therapy (PDT) utilizing Hematoporphyrin Derivative (HpD) injection has been demonstrated as an efficacious treatment for various conditions, including Bowen's disease, subtypes of basal cell carcinomas, and actinic keratosis. While surgical resection is considered the primary treatment option for extramammary Paget's disease (EMPD), some patients may not be suitable candidates for surgical intervention. ALA-PDT may have some benefits in treating EMPD in select patients, while Hematoporphyrin Derivative-Photodynamic Therapy (HpD-PDT) has demonstrated promising potential as a cancer treatment. We present one case of vulvar extramammary Paget's disease (EMPD), that is a female patient with lesions in the vulva and involving the urethra. Due to advanced age, underlying diseases, the extensive affected area, and the specific location of the vulvar lesion, the patients were unable to undergo surgical treatment. Therefore, the patient declined traditional wide local excision and instead opted for hematoporphyrin photodynamic therapy. Treatment eliminated the tumor, but it recurred locally after 1.5 years of follow-up. Localized small-scale recurrence at the affected site can be treated with surgical resection or photodynamic therapy to achieve complete clearance of the lesion. However, the patient refuses further examination and treatment. EMPD has a high recurrence rate, but we propose that hematoporphyrin photodynamic therapy is an effective alternative to conventional surgery for treating this condition, even in case of recurrence.

[Research progress of the anti-tumor effect of sonodynamic and photodynamic therapy].

Cancer, as a serious threat to human health, is one of the major killers. The treatment of cancer has attracted more and more attention. Currently, the means of treating cancer is also increasing, but there is no emergence of a fully satisfactory treatment. A combination of sonodynamic therapy (SDT) and photodynamic therapy (PDT), named sono-photodynamic therapy (S-PDT), is a new composite cancer therapy. Because the therapy can significantly improve the tumor curing effect, it has good application prospects in cancer prevention and treatment. The present article reviewed the progress of the anti-tumor mechanisms and influencing factors of S-PDT.

Vacata- and divacataporphyrin: new photosensitizers for application in photodynamic therapy-an in vitro study.

BACKGROUND AND OBJECTIVE: The photodynamic therapy is a well-known method of treatment of both malignant tumors and non-tumor lesions in human patients. In the present study, we aimed at evaluating the in vitro efficacy of the new photosensitizing agents, vacataporphyrin (VP), and divacataporphyrin (DVP). MATERIALS AND METHODS: The effectiveness of VP and DVP was compared to well-known photosensitizers, that is, hematoporphyrin derivative (HPD) and chlorin e6 (Ce6) in identical in vitro conditions. The experiment was performed on a well-established breast cancer cell line, MCF-7 and compared to HCV 29T11-2-D1 cell line. Cells were incubated in standard conditions and they were exposed to different concentrations of VP, DVP, HPD, and Ce6, that is, 180, 90, 45, 22.5, and 10 µg/ml. After incubation with photosensitizers, the cells were washed, medium was exchanged and the cells were subjected to irradiation at the proper wavelengths, light intensity (100 mW/sq cm), and total light doses 4.5 and 9 J/sq cm. RESULTS: Our results showed that the VP and DVP are potent photosensitizers and the photocytotoxic effect after the incubation with DVP was much better than that of VP. The cytotoxic effects of VP and DVP were less intensive than these of HPD and Ce6. VP and DVP also accumulated well in the tumor cells. Our results also indicated that the VP and DVP effectiveness on MCF-7 cells was photosensitizer dose and light dose dependent. CONCLUSION: The overall properties revealed by both new porphyrins and particularly a possibility for excitation at a higher wavelength and thus a deeper tissue penetration, make them promising candidates for further in vivo experiments.

The influence of electroporation on in vitro photodynamic therapy of human breast carcinoma cells.

Phototoxicity of drugs used in cancer photodynamic therapy could be augmented by increased accumulation of a photosensitizer in target cells. The intracellular delivery mode that enhances drug transportation could facilitate therapy by reducing the exposure time. Doses of the administered drug and related side effects could be lowered, whilst maintaining the same therapeutic efficiency. Electroporation supports transport of many drugs by creating electric field-induced transient nanopores in the plasma membrane. In this study, the electroporation- assisted transport of a photosensitizer was tested in vitro in human breast carcinoma cell lines: wild-type (MCF-7/WT) and doxorubicin-resistant (MCF-7/DOX). The efficacy of photodynamic therapy alone and in combination with electroporation was evaluated by cell viability with MTT test, using a haematoporphyrin derivative as a model. The data presented show up to 10-fold greater efficacy of the combined method, with very significantly reduced drug exposure times.

Effect of a newly synthesized Zn sulfophthalocyanine derivative on cell morphology, viability, proliferation, and cytotoxicity in a human lung cancer cell line (A549).

Photodynamic therapy (PDT) is a photochemotherapeutic process that is used for the treatment of cancer. Photofrin is the most widely used photosensitizer, however, the chemical composition of Photofrin is unclear and it has a low absorption in the therapeutic wavelength (600-900 nm). This factor has stimulated research in synthesis and testing of new photosensitizers. This in vitro study evaluated the effectiveness of a Zn sulfophthalocyanine (ZnPcS(mix)) as a potential photosensitizer in the treatment of human lung cancer. Lung cancer cells (A549) were divided into four groups: group 1 was control cells receiving neither light nor drug; group 2 was light control for cells exposed to laser irradiation at a fluence of 4.98 J/cm(2); group 3 was drug control for cells incubated with 15.8 µM photosensitizer and not exposed to laser irradiation, while group 4 was cells receiving the experimental treatment with 15.8 µM photosensitizer and irradiation with 4.98 J/cm(2). Laser irradiations were performed using a 636-nm diode laser with an output power of 110 mW at 4.98 J/cm(2). Changes in cellular responses were evaluated by cell morphology, viability, proliferation, and cytotoxicity. While control groups 1, 2, and 3 showed no changes in cell morphology, viability, proliferation, or cytotoxicity, group 4 receiving both photosensitizer and irradiation showed changes in cell morphology, a decrease in cell viability and proliferation, and an increase in cytotoxicity, cell death, and cell membrane damage. Irradiation or photosensitizer alone had no effect on the lung cancer cells since the cells remained viable and showed no evidence of damage. However, irradiation in the presence of a photosensitizer induced cell death.

Active oxygen intermediates in the degradation of hematoporphyrin derivative in tumor cells subjected to photodynamic therapy.

Hematoporphyrin derivative (HPD), a sensitizer used in photodynamic therapy (PDT) of malignancies, is progressively destroyed during the treatment. Prior studies suggested that upon PDT the photobleaching of HPD in tumor tissues is largely mediated by self-sensitized singlet oxygen. However, little is known about the role of other reactive oxygen species (ROS). The main aim of this work was to clarify the significance of H2O2, superoxide (O2.(-)) and hydroxyl (OH.) radicals in bleaching of HPD in tumor cells subjected to PDT. Experiments were performed on Ehrlich ascites carcinoma (EAC) cells, which were loaded with HPD in PBS and then irradiated with red light at 630 nm in the same buffer. Studies showed that photosensitization of EAC cells by HPD led to the formation of significant amounts of H2O2, O2.(-) and OH., and that these ROS could be involved in the photobleaching of HPD during PDT. In fact, we found that addition of catalase (CAT, a scavenger H2O2), Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and Tiron (scavengers of O2.(-)), Na-benzoate, mannitol and deferoxamine (scavengers of OH.) caused a substantial decrease in the rate of HPD photobleaching in EAC cells. In these cells, the inhibitory effects of Na-benzoate, mannitol and deferoxamine on the photodegradation of HPD correlated well with suppression of the OH. generation, a highly active oxidizer. In EAC cells, the glutathione redox cycle and CAT (scavengers of H2O2) as well as Cu/Zn-SOD was found to suppress the photoinduced degradation of HPD. It was also established that HPD can directly scavenge H2O2 and oxygen free radicals; in a phosphate buffer its second-order rate constants were measured as 5.51+/-0.32 x 10(3)M(-1)s(-1) (for the reaction with O2.(-)), 5.08+/-0.31 x 10(4)M(-1)s(-1) (for H2O2), and 3.44+/-0.08 x 10(10)M(-1)s(-1) (for OH.). Thus, our data suggest that OH. could be one of the main oxidants mediating the photobleaching behavior of HPD in malignancies. Studies showed that photoexcited moieties of HPD can oxidize cell proteins with the formation of protein peroxides (PPO), which currently are regarded as a new form of ROS. Model experiments suggest that PPO could also participate in bleaching of HPD in tumors treated with PDT. It was found that HPD may destroy in tumor cells after cessation of photoirradiation and that this event is largely mediated by the presence of H2O2, a precursor of OH(.).

Early diagnosis of cancer by detecting the chemiluminescence of hematoporphyrins in peripheral blood lymphocytes.

Early detection and optimal treatment are the most effective means to improve cancer mortality. Mass screening for cancer has yielded a marked reduction of cancer mortality in the United States. Simple and effective methods are expected for screening of malignancy. Hematoporphyrin derivatives (HPDs) are known to accumulate in cancer cells; thus, HPD has been used for local diagnosis and photodynamic therapy of cancer. The lymphocytes of cancer patients also demonstrate the active uptake of HPD and this phenomenon has been applied for the diagnosis of cancer. In the present study, we have developed a novel method for measurement of the chemiluminescence of HPD in peripheral blood lymphocytes. HPD is composed of hematoporphyrin and its oligomers. Seven cancer patients and seven controls were recruited for this study. The primary cancers included two prostate cancers (one without metastasis and the other with lung metastasis), a renal cancer, a lung adenocarcinoma with systemic metastasis, two gallbladder cancers with lung metastasis, and a colon cancer with liver metastasis. HPD in lymphocytes was measured using a highly sensitive chemiluminescence analyzer with laser light irradiation to detect photoemission by (1)O(2) from HPD. The intensity of chemiluminescence exhibited a linear correlation with the concentrations of HPD. In addition, the level of HPD in lymphocytes was significantly higher in cancer patients than that in healthy volunteers (p < 0.05). These results suggest that detection of the chemiluminescence of HPD in lymphocytes could be a sensitive and simple method for cancer diagnosis and screening.

Identification of porphyrin modified photosensitizer porfimer sodium and its precursors by high performance liquid chromatography and mass spectrometry.

Photodit (porfimer sodium) is a complex mixture of porphyrin-modified oligomers that has demonstrated high photoactivity during photodynamic therapy of malignant tumors. Hematoporphyrin derivative monomer precursors of Photodit and its oligomers were analyzed using liquid chromatography and mass spectrometry to determine their chemical composition and structures. Hematoporphyrin (M-3), O,O'-diacetylhematoporphyrin (M-6), and isomers of 8(-3)-hydroxyethyl-3(-8)-vinyldeuteroporphyrin (M-2), 8(-3)-(1-acetoxyethyl)-3(-8)-vinyldeuteroporphyrin (M-4), and O-acetylhematoporphyrin (M-5), in ratio 0.59:0.94:0.21:0.34:1.00, were identified as hematoporphyrin derivative monomer precursors. The main compounds of Photodit as a porfimer sodium salt were dimers: D-1 [di-[8(-3)-hydroxyethyl-3(-8)-vinyldeuteroporphyrin] ether], D-2 [[Hematoporphyrin-8(-3)-hydroxyethyl-3(-8)-vinyldeutroporphyrin] ether], and D-3 [Dihematoporphyrin ether] in ratio 0.51:1.00:0.50, and trimers: T-1 [(M-2)-(D-2) ether], T-2 [(D-2)-(M-3) ether], and T-3 [(D-3)-(M-3) ether] in ratio 0.98:1.00:0.44, respectively. An average oligomer length of 2.23 porphyrin units was determined.