Synthesis and evaluation of novel fluorinated hematoporphyrin ether derivatives for photodynamic therapy.

A photosensitizer with high phototoxicity, suitable amphipathy and low dark toxicity could play a pivotal role in photodynamic therapy (PDT). In this study, a facile and versatile approach was adopted to synthesize a series of novel fluorinated hematoporphyrin ether derivatives (I1-I5 and II1-II4), and the photodynamic activities of these compounds were studied. Compared to hematoporphyrin monomethyl ether (HMME), all PSs showed preferable photodynamic activity against A549 lung tumor cells. The longest visible absorption wavelength of these compounds was approximately 622 nm. Among them, II3 revealed the highest singlet oxygen yield (0.0957 min-1), the strongest phototoxicity (IC50 = 1.24 µM), the lowest dark toxicity in vitro, and exhibited excellent anti-tumor effects in vivo. So compound II3 could act as new drug candidate for photodynamic therapy.

The photodynamic activity of 131-[2'-(2-pyridyl)ethylamine] chlorin e6 photosensitizer in human esophageal cancer.

A novel 131-pyridine substituted chlorin e6 derivative (Chlorin A) was synthesized. It has characteristic long wavelength absorption at 664 nm and the emission wavelength at 667 nm. The generation rate of singlet oxygen of this compound is higher than Temoporfin. In vitro, Chlorin A showed higher phototoxicity against the human esophageal cancer cells than Temoporfin while with lower dark-toxicity. Its accumulation effect in mitochondria, lysosomes and endoplasmic reticulum was traced in subcellular localization tests. In flow cytometry obvious apoptosis cells were observed after 2 h irradiation. Significant in vivo photodynamic anti-tumor efficacy was also exhibited on mice bearing esophageal cancer. So Chlorin A could be suggested as a promising anti-tumor drug candidate in photodynamic therapy.

Synthesis and biological evaluation of 173-dicarboxylethyl-pyropheophorbide-a amide derivatives for photodynamic therapy.

Three novel 173-dicarboxylethyl-pyropheophorbide-a amide derivatives as photosensitizers for photodynamic therapy (PDT) were synthesized from pyropheophorbide-a (Ppa). Their photophysical and photochemical properties, intracellular localization, photocytotoxicity in vitro and in vivo were investigated. All target compounds exhibited low cytotoxicity in the dark and remarkable photocytotoxicity against human esophageal cancer cells. Among them, 1a showed highest singlet oxygen quantum yield. Upon light activation, 1a exhibited significant photocytotoxicity. After PDT treatment, the growth of Eca-109 tumor in nude mice was significantly inhibited. Therefore, 1a is a powerful and promising antitumor photosensitizer for PDT.

Synthesis and evaluation of new 5-aminolevulinic acid derivatives as prodrugs of protoporphyrin for photodynamic therapy.

Protoporphyrin IX (PpIX) is used as a photosensitizer in the photodynamic diagnosis (PDD) and photodynamic therapy (PDT) of cancer and is synthesized intracellularly from 5-aminolevulinic acid (5-ALA) precursors. Thirteen novel 5-ALA derivatives were designed and synthesized appropriately with tailored hydrophilicity and lipophilicity. The generation of PpIX was detected and their antitumor activity in vitro and in vivo was also investigated. It was shown that compounds 9b-c, 11b-c and 13a displayed a characteristic long wavelength absorption peak at 593 nm after 5 h incubation in mice fibrosarcoma S180 cells. After being exposed to 600 nm laser light irradiation, these compounds can inhibit cell proliferation in S180 cells in vitro. The growth of S180 cell tumors in Kunming mice was significantly inhibited by these compounds in vivo. Among these compounds, 13a has low dark toxicity and high phototoxicity, which makes it an effective and promising prodrug for PDT.

Synthesis of 2-morpholinetetraphenylporphyrins and their photodynamic activities.

A series of 2-morpholinetetraphenylporphyrins functionalized with various substituents (Cl, Me, MeO group) at 4-phenyl position were prepared via nucleophilic substitution of 2-nitroporphyrin copper derivatives with morpholine by refluxing under a nitrogen atmosphere and then demetalization. Their basic photophysical properties, intracellular localization, cytotoxicities in vitro and in vivo were also investigated. All synthesized photosensitizers exhibited longer maxima absorption wavelengths than Hematoporphyrin monomethyl ether (HMME). They showed low dark cytotoxicity compared with that of HMME and were more phototoxic than HMME against Eca-109 cells in vitro. M3 also exhibited better photodynamic antitumor efficacy on BALB/c nude mice at a lower concentration. Therefore, M3 is a promising antitumor photosensitizer in photodynamic therapy application.

Synthesis, photophysical properties and biological evaluation of ß-alkylaminoporphyrin for photodynamic therapy.

A series of ß-alkylaminoporphyrins conjugated with different amines at ß position (D1-D3) or with electron-donating and electron-withdrawing substituents at phenyl position (D4-D6) were synthesized. Their photophysical and photochemical properties, intracellular localization, photocytotoxicities in vitro and vivo were also investigated. All target compounds exhibited no cytotoxicities in the dark and excellent photocytotoxicities against HeLa cells. Among them, D6 showed the highest phototoxicity and the lowest dark toxicity, which was more phototoxic than Hematoporphyrin monomethyl ether (HMME). In addition, D6 exhibited best photodynamic antitumor efficacy on BALB/c nude mice bearing HeLa tumor. Therefore, D6 is a powerful and promising antitumor photosensitizer for photodynamic therapy.

Glomangiomatosis - immunohistochemical study: A case report.

BACKGROUND: Glomangiomatosis (also known as diffuse glomus tumor) is extremely rare, accounting for only 5% of glomus tumors. The prevalence of glomus tumors is only 2% of soft tissue tumors. Lesions can recur after resection. Although growth may be diffuse or infiltrating and invasive, definitive identifying standards for malignant glomus tumors are lacking. This article describes a case of glomangiomatosis with many nodular masses in the soft tissues of the right foot and calf. A review of the Chinese and English-language literature is included. CASE SUMMARY: A case of glomangiomatosis in a 55-year-old Chinese woman who presented clinically with many nodular masses in the soft tissues of the right foot and calf. The tumor was examined histologically and immunostaining was performed. CONCLUSION: Glomangiomatosis occurs most often in young people, in the distal extremities, but is rare. Multiple nodules are even rarer. Only 15 clinicopathological analyses of glomangiomatosis have been reported in the combined Chinese- and English-language literature. In the present case, microscopically, nested vascular globular cells were observed around the blood vessel wall. Immunohistochemistry revealed diffuse immunoreactivity for smooth muscle actin, vimentin, type IV collagen, and Bcl-2. Caldesmon, CD34, and calponin were weakly, partially, and slightly positive, respectively. There was no recurrence 1 year after resection.

Synthesis and pharmacological evaluation of chlorin derivatives for photodynamic therapy of cholangiocarcinoma.

Photodynamic therapy (PDT) has been developed as a promising therapeutic method in cancer treatment. The discovery of effective photosensitizer, which is the key factor of PDT, is highly desired. This paper reports the synthesis of novel chlorin derivatives, 5,10,15,20-tetraphenyl-[2:3]-[(methoxycarbonyl, carboxy)methano] chlorin I and 5,10,15,20-tetraphenyl-[2:3]- {[methoxycarbonyl, (2-hydroxyethyl)amide]methano}chlorin II. Their structures were characterized with UV-vis, 1HNMR, 13CNMR and HRMS spectroscopies. Photophysical and photochemical experiments results showed that compound I and II had an absorption maximum around 650 nm, with molar extinction coefficients of 1 × 104 M-1 cm-1. They had strong fluorescence emission in 650-660 nm upon excitation with 419-422 nm light. ESR showed that singlet oxygen was produced upon irradiation of compounds with 650 nm light in the presence of molecular oxygen. The photo-bleaching test indicated that the structure of compounds was stable. These new compounds exhibit excellent anti-tumor effects and lower toxicity compared to m-THPC in vitro and in vivo. Compound I and II had high tumor selectivity, which could induced tumor cells shrinkage and necrosis under 650 nm laser irradiation. Flow cytometry revealed that the compounds might mediate PDT effect at late apoptotic phase. These results make these compound I and II promising candidates for future study in photo-diagnosis and photodynamic therapy of cholangiocarcinoma.

Synthesis and evaluation of novel chlorophyll a derivatives as potent photosensitizers for photodynamic therapy.

Chlorophyll a exhibits excellent photosensitive activity in photosynthesis. The unstability limited its application as photoensitizer drug in photodynamic therapy. Here a series of novel chlorophyll a degradation products pyropheophorbide-a derivatives were synthesized and evaluated for lung cancer in PDT. These compounds have strong absorption in 660-670 nm with high molar extinction coefficient, and fluorescence emission in 660-675 nm upon excitation with 410-415 nm light. They all have much higher ROS yields than pyropheophorbide-a, and compound 10 was even higher than [3-(1-hexyloxyethyl)]-pyrophoeophorbide a (HPPH). Distinctive phototoxicity was observed in vitro and the inhibition effect was in light dose-dependent and drug dose-dependent style. They can effectively inhibit the growth of lung tumor in vivo. Among them, compound 8 and 11 have outstanding photodynamic anti-tumor effects without obvious skin photo-toxicity, so they can act as new drug candidates for photodynamic therapy.

The photodynamic activities of dimethyl 131-[2-(guanidinyl)ethylamino] chlorin e6 photosensitizers in A549 tumor.

Effective photosensitizers are particularly important factor in clinical photodynamic therapy (PDT). However, there is a scarcity of photosensitizers for simultaneous cancer photo-diagnosis and targeted PDT. Herein, two novel dimethyl 2-(guanidinyl)ethylamino chlorin e6 photosensitizers were synthesized and their efficacy in PDT in A549 tumor was investigated. It was shown that compounds 3 and 4 have a long absorption wavelength in the near infrared region and strong fluorescence emission with slow photo-bleaching rate and markedly strong ability of 1O2 generation. They exhibited lower cytotoxicity and higher photo-cytotoxicity in vitro compared to the known anticancer drug m-THPC in MTT assay in A549 lung cancer cell lines. Compound 4 exhibit better inhibition effect than compound 3 and the IC50 value of compound 4 was 0.197 µM/L under 2 J/cm2 laser irradiation, while compound 3 showed better anti-tumor effects compared to compound 4 in vivo. Intracellular ROS generation was found to be responsible for apoptotic cell death in DCFDA assay. Subcellular localization confirmed the damage site of compounds 3 and 4 in PDT. These findings suggest that the two novel photosensitizers might serve as potential photosensitizers for improved therapeutic efficiency of PDT.

Comparison between porphin, chlorin and bacteriochlorin derivatives for photodynamic therapy: Synthesis, photophysical properties, and biological activity.

The development of novel photosensitizers is a challenging task for photodynamic therapy (PDT). Twelve novel photosensitizers (PSs), including porphins (P1-4), chlorins (C1-4) and bacteriochlorins (B1-4) were synthesized. The bacteriochlorins exhibited the longest absorption wavelength (λmax = 736 nm), which is higher than that of porphins (λmax = 630 nm) and chlorins (λmax = 644 nm). In vitro photodynamic activities on Eca-109 human esophageal carcinoma cells were evaluated by standard assays and all PSs showed photodynamic activity. Among them, B2 displayed the highest phototoxicity and the lowest dark toxicity. In addition, B2 exhibited best photodynamic antitumor efficacy on BALB/c nude mice bearing Eca-109 cells tumor. Therefore, B2 is a powerful and promising antitumor photosensitizer for PDT.

Preparation of a chlorophyll derivative and investigation of its photodynamic activities against cholangiocarcinoma.

Photodynamic therapy (PDT) is emerging as a promising method for the treatment of various cancer diseases. However, the clinical application of PDT is limited due to the lack of effective photosensitizers. In this study, a novel chlorophyll derivative, N,N-bis(2-carboxyethyl)pyropheophorbide a (BPPA), had been synthesized and characterized. BPPA had a characteristic long wavelength absorption peak at 669nm and a singlet oxygen quantum yield of 0.54. To investigate the photodynamic ability of BPPA against cholangiocarcinoma (CCA), cellular uptake, subcellular location and bio-distribution, in vitro and in vivo PDT efficacy of BPPA were studied. The results showed that BPPA could rapidly accumulate in QBC-939 cells and localize in the cytoplasm. BPPA- PDT was effective in reducing the cell viability in a drug dose- and light dose-dependent manner in vitro. In CCA xenograft nude mouse model, the concentration of BPPA in the plasma lowered rapidly, and the fluorescence signal peaked at 0.5h and 2h after injection in the skin and tumor, respectively. Significant quantities could be observed in the tumor. BPPA followed by irradiation could significantly inhibit growth of tumors, and histological examination revealed necrotic damage in PDT-treated tumors. These results suggested that BPPA could be a promising drug candidate for photodynamic therapy in cholangiocarcinoma.

Tetraphenylporphyrin derivatives possessing piperidine group as potential agents for photodynamic therapy.

Photodynamic therapy (PDT) is a noninvasive therapeutic and promising procedure in cancer treatment and has attracted considerable attention in recent years. In the present paper, 2-piperidinetetraphenylporphyrin derivatives (P1-P3) conjugated with different substituents (Cl, Me, MeO group) at phenyl position were synthesized via nucleophilic substitution of 2-nitroporphyrin copper derivatives with piperidine by refluxing under a nitrogen atmosphere and then demetalization. The combination of 1H NMR, 13C NMR and HR-MS was used to elucidate the identities of them. Their photophysical and photochemical properties, intracellular localization, cytotoxicity in vitro and in vivo against QBC-939 cells were investigated. They have absorption at wavelength about 650nm. All synthesized photosensitizers showed low dark cytotoxicity and comparable with that of hematoporphyrin monomethyl ether (HMME). And they were more phototoxic than HMME to QBC-939 cells in vitro. In bearing QBC-939 tumor BALB/c nude mice, when it treated with 5mg/kg dose of PS and laser light (650nm, 100J/cm2, 180mW/cm2), the growth of tumor was inhibited compared to the control group. Among them, P3 exhibited better photodynamic antitumor efficacy on BALB/c nude mice at lower concentration. These results indicate that P3 is a new potential antitumor photosensitizer in photodynamic therapy and deserves further investigation.