title: Efficacy of multiple low-dose photodynamic TMPYP4 therapy on cervical cancer tumour growth in nude mice.
abstract: OBJECTIVE
  Photodynamic therapy (PDT) is an emerging therapeutic procedure suitable for the treatment of cervical cancer. However, the side effects of PDT are severe, including skin ulceration, so we designed an experiment to examine the effects of multiple low- dose photodynamic therapy of 5, 10, 15, 20-tetrakis(1- methylpyridinium-4-yl) porphyrin (Tmpyp4) on tumour growth by utilizing a model in nude mice implanted with Hela cervical cancer cells.
  
  
  METHODS
  Female BALB/c nude mice (aged 5-6 weeks, weighing 18-20 g) were used. Hela cervical cancer cells were injected subcutaneously (1 x 10(7) cells/200 μL). Ten days after injection, the mice were divided into three groups (n=6), the A group of controls without any treatment, the B group receiving a single-treatment with Tmpyp4 (10 mg/kg, intratumor injection) and irradiation (blue laser, 108 J/cm(2)), and the C group given three-treatments with Tmpyp4 (10 mg/ kg, intratumor injection) and irradiation at intervals of two days. After starting treatment, tumours were measured every two days, to assess growth. At 2 weeks after the last treatment of C group, tumour tissue and organs were collected from each mouse to evaluate tumor histology and organ damage.
  
  
  RESULTS
  Tumour growth in C group was significantly inhibited compared with A and B groups (P <0.05), without any injury to the skin and internal organs.
  
  
  CONCLUSIONS
  Our novel findings demonstrated that multiple low-dose photodynamic therapy of Tmpyp4 could inhibit cervical cancer growth significantly with no apparent side effects.
authors.affiliation: Department of Gynecology and Obstetrics, Qilu Hospital of Shandong Univeristy, Jinan, China E-mail : zhangyouzhong0810@126.com.
authors.forename: Ai-Hong
authors.initials: AH
authors.lastname: Liu
authors.forename: Xuan
authors.initials: X
authors.lastname: Sun
authors.forename: Xiao-Qiang
authors.initials: XQ
authors.lastname: Wei
authors.forename: You-Zhong
authors.initials: YZ
authors.lastname: Zhang
mesh_terms: D000818:Animals; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011166:Porphyrins / Q000627:therapeutic use*; D047368:Tumor Burden; D014407:Tumor Cells, Cultured; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy* / Q000473:pathology
chemical_list: D017319:Photosensitizing Agents; D011166:Porphyrins; C021096:tetra(4-N-methylpyridyl)porphine