Photodynamic therapy (PDT) was first used for the treatment of esophageal cancer in early 1980s, Since then, numerous applications have been reported for its use in gastrointestinal tract including Barrett's esophagus, gastric, duodenal, biliary, pancreatic and colorectal lesions. PDT in gastroenterology has made tremendous progress over the last decade but its clear role is yet to be proved. Now, there is an increasing need for less invasive methods of treatment in patients with pre-malignant disease, early cancer or those who are unfit for surgery. It is one of a number of ablative techniques currently under investigation and appears to have a number of potential advantages over other forms of treatment in the alimentary tract. The development of newer potent, highly efficient photosensitizers, as well as endoscopic imaging techniques and light delivery systems, are continuing to expand the clinical uses of PDT. As data from additional clinical trials become available, we will gain a clearer perspective of where PDT fits in the treatment of cancers.
Digestive System Diseases/*drug therapy ; English Abstract ; Humans ; *Photochemotherapy ; Photosensitizing Agents/administration & dosage

OBJECTIVE: To observe the effect of the three stages of 5-aminolevulinic acid-photodynamic therapy (ALA-PDT) on condyloma acuminatum of external urethral meatus. METHODS: A total of 56 patients with condyloma acuminatum of external urethral meatus presenting at the Department of Dermatology of Xiangya Hospital from Janunary 2009 to September 2009 were randomly treated by the three stages of ALA-PDT. The topical ALA followed by PDT was carried out once a week for 3 weeks. Rates of cure, ineffectiveness, adverse effects and complications were observed. The follow-up time was 6 months and the recurrence rates were documented. RESULTS: After treatment of three stages of ALA-PDT, complete remission was achieved in 48 out of the 56 patients (85.7%). The recurrence rate was 14.3% (8 cases), and 2 patients had no responses (3.6%). Only 1 patient had serious pain during the treatment, and the rate of adverse effect was 1.8%. No complications were observed. CONCLUSION The three stages of ALA-PDT are safe, effective and tolerant treatment for condyloma acuminatum of external urethral meatus.
Adult ; Aminolevulinic Acid ; administration & dosage ; Condylomata Acuminata ; drug therapy ; Humans ; Male ; Photochemotherapy ; Photosensitizing Agents ; administration & dosage ; Urethral Diseases ; drug 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.
Animals ; Antineoplastic Agents ; administration & dosage ; Combined Modality Therapy ; Hematoporphyrin Derivative ; administration & dosage ; Hematoporphyrin Photoradiation ; Humans ; Neoplasms ; drug therapy ; therapy ; Photochemotherapy ; methods ; Photosensitizing Agents ; administration & dosage ; Ultrasonic Therapy ; methods

Photodynamic therapy is a promising modality for the palliation of advanced upper gastrointestinal cancer and for the eradication of early neoplastic and pre-neoplastic lesions. It is based on the combination of a photosensitizer that is selectively localized in the target tissue and illumination of the lesion with visible light, resulting in photodamage and subsequent cell death. For early esophageal cancer, esophagectomy has been a standard modality of curative intent. However, accumulated data supports the possibility of PDT replacing surgery as a curative modality. We experienced a case of early esophageal cancer that recurred after esophagectomy. The patient was successfully treated with photodynamic therapy using porfimer sodium as a photosensitizer.
Endoscopy, Gastrointestinal ; Esophageal Neoplasms/*drug therapy/pathology/surgery ; *Esophagectomy ; Humans ; Male ; Middle Aged ; *Photochemotherapy ; Photosensitizing Agents/administration & dosage/*therapeutic use

Photodynamic therapy (PDT) has been used to treat several types of cancer, and comprises intravascular administration of photosensitizer, uptake by cancer cells, and followed by irradiation of light of appropriate wavelength. Although PDT takes advantage of relative retention of photosensitizer by cancer cells, effective delivery of photosensitizing drugs is of great concern. Several delivery strategies have been employed in PDT. Photosensitizers can be delivered either by passive carriers such as liposomes, micelles, and polymeric particles, or by active targeting using cancer cell-directed ligands or antibodies. Although well-studied colloidal carriers effectively deliver photosensitizer to tumor cells, they are taken up by mononuclear phagocytic system. Delivery system using polymers is an attractive alternative to colloidal carriers, in which hydrophobic drugs are chemically or physically loaded to polymers. Though there are several steps to be solved, targeted delivery system utilizing receptors or antigens abundantly expressed on cancer cell theoretically provides a great deal of advantages over passive system. Selective uptake of photosensitizers by cancer cells may greatly enhance therapeutic efficacy as well as minimizing adverse effects resulting from accumulation in normal tissue. This review discusses various strategies for photosensitizer delivery that have been investigated to date.
Drug Delivery Systems ; Humans ; Liposomes/chemistry ; Micelles ; Neoplasms/*drug therapy ; *Photochemotherapy ; Photosensitizing Agents/*administration & dosage ; Polymers/chemistry/therapeutic use

With recent developments in photosensitizers and light delivery systems, topical 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) has become the fourth alternative therapeutic approach in the management of oral leucoplakia (OLK) due to its minimally invasive nature, efficacy, and low risk of systemic side effects and disfigurement. This report presents step-by-step guidelines for applying topical ALA-PDT in the management of OLK based on both the clinical experience of the authors and a systematic review of the current literature. Studies using protocols with standardized parameters and randomized clinical trials at multiple centres with adequate sample sizes and both interim and long-term follow-ups are needed before universally applicable guidelines can be produced in this field.
Aminolevulinic Acid ; administration & dosage ; therapeutic use ; Humans ; Leukoplakia, Oral ; therapy ; Photochemotherapy ; methods ; Photosensitizing Agents ; administration & dosage ; therapeutic use ; Practice Guidelines as Topic

Targeted drug delivery can significantly increase the concentration of the drug in treatment site, and decrease the dosage of drugs, cost of treatment and the drug's adverse effects on the body. So targeted drug delivery is the hotspot of recent studies. This paper reviews the development of targeted drug delivery research in recent years, including three areas: passive targeting, active targeting, and physical and chemical targeting.
Animals ; Antibodies ; metabolism ; Drug Carriers ; Drug Delivery Systems ; methods ; trends ; Emulsions ; Humans ; Liposomes ; Magnetics ; Microspheres ; Nanoparticles ; Pharmaceutical Preparations ; administration & dosage ; Photosensitizing Agents ; pharmacology ; Prodrugs ; Receptors, Cell Surface ; metabolism

OBJECTIVETo explore the possible mechanism of apoptosis induced by photodynamic therapy (PDT) in human pancreatic cancer cells Capan-1 with 2-butylamino-2-demethoxy-hypocrellin B (BAHB) as photosensitizer.

METHODSThe localization of BAHB in Capan-1 cells was studied, apoptosis was determined by DNA gel electrophoresis after PDT. The mitochondria membrane potential (DYm) and cytochrome C release were observed by laser scan confocal microscopy and Western blotting.

RESULTSThe low concentration photosensitizer was mainly localized in mitochondria and also in lysosomes when the concentration is high. DNA ladder analysis showed characteristic of apoptosis. The mitochondria membrane potential (DYm) showed a loss of 30% around, after 6 hours by PDT under laser scan confocal microscopy, which is caused by a sudden increase in the permeability of mitochondria membrane accompanied with apoptosis. In Western blotting, cytochrome C release was observed from the mitochondria into the cytoplasm during BAHB-induced apoptosis.

CONCLUSIONThe research suggests that BAHB-induced apoptosis is related to photosensitization of mitochondria.

Apoptosis ; drug effects ; Dose-Response Relationship, Drug ; Humans ; Membrane Potentials ; drug effects ; Mitochondria ; drug effects ; physiology ; Pancreatic Neoplasms ; drug therapy ; pathology ; Perylene ; administration & dosage ; analogs & derivatives ; pharmacology ; Photochemotherapy ; Photosensitizing Agents ; administration & dosage ; pharmacology ; Quinones ; administration & dosage ; pharmacology ; Tumor Cells, Cultured

AIMTo investigate the penetration kinetics of xanthotoxin in human skin and stratum corneum.

METHODSThe penetration experiments were accomplished by the deposit of ethanolic xanthotoxin solution onto human skin and stratum corneum mounted on Franz cells. The diffused xanthotoxin in the receptor solution (1.4% human serum albumin) and the retained amount in the skin and in the stratum corneum after 24 h exposure were quantified by using high performance liquid chromatography.

RESULTSXanthotoxin flux was increased with the concentration deposited onto the human skin, and when the concentration is above 2.5 mg x mL(-1), there is no influence on the xanthotoxin flux. Similar results were obtained from the stratum corneum. And the peak time for the flux in the stratum corneum was preceded about 6 h earlier than that of the whole human skin. The retained xanthotoxin amount after 24 h exposure in the skin and in the stratum corneum increased according to the concentration deposited and has the tendency to saturate. The lag time of ethanolic xanthotoxin solution in the whole human skin is significantly higher than that in the stratum corneum (P < 0.05).

CONCLUSIONThe characteristics of penetration kinetics of xanthotoxin will provide the information for concentration choice of topical formulation and give a reference for ultra violet A (UVA) irradiation time confirmation.

Administration, Cutaneous ; Dose-Response Relationship, Drug ; Epidermis ; metabolism ; Female ; Humans ; In Vitro Techniques ; Methoxsalen ; administration & dosage ; pharmacokinetics ; Middle Aged ; Photosensitizing Agents ; administration & dosage ; pharmacokinetics ; Skin ; metabolism ; Skin Absorption ; Time Factors

This investigation was made with regard to the influences of ultrasound combined with hematoporphyrin on the activities of antioxidative enzyme in ascites hepatoma 22 (H-22) tumor cells, and to a better understanding of the potential biological mechanism of sonodynamic therapy which involved the damage to cells. Combined with 100 microg/ml hematoporphyrin, high intensity focused ultrasound sonication at a frequency of 1.43 MHz and an intensity level of 2.0 W/cm2 was delivered to H-22 tumor cells for 1 min. The viability of cells was evaluated by typan-blue blue exclusion test. The intracellular reactive oxygen species (ROS) levels were determined by 2',7'-dichlorofluorescein diacetata (DCFH-DA). Enzymatic chemical methods were used to measure the activities of key antioxidative enzymes. The results indicated that the cell damage rate of ultrasound combined with hematoporphyrin was significantly higher than that of the treatment with ultrasound alone, and hematoporphyrin alone had no killing effect on H-22 cells. The level of ROS in cell suspension was significantly increased, and the key antioxidative enzyme activities were obviously decreased after treatment with the combined use of ultrasound and hematoporphyrin. We speculated that the decreased activities of key antioxidative enzymes in cells might be involved in mediating the killing effect on H22 cells in sonodynamic therapy.
Animals ; Female ; Glutathione Peroxidase ; metabolism ; Hematoporphyrins ; administration & dosage ; radiation effects ; Liver Neoplasms, Experimental ; enzymology ; therapy ; Mice ; Mice, Inbred ICR ; Photochemotherapy ; methods ; Photosensitizing Agents ; administration & dosage ; radiation effects ; Superoxide Dismutase ; metabolism ; Ultrasonics