title: Efficacy of combined therapy with paclitaxel and low-level ultrasound in human chronic myelogenous leukemia cell line K562.
abstract: BACKGROUND
  Sonochemotherapy, which applies ultrasound in cancer chemotherapy, has been proven to be a promising therapeutic modality by some previous researches.
  
  
  OBJECTIVE
  To investigate the interaction between an antineoplastic agent - paclitaxel (PTX) and low-level ultrasound in human chronic myelogenous leukemia cell line K562, their combined efficacy, and the potential mechanisms in sonochemotherapy.
  
  
  METHODS
  3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) analysis and Guava Viacount assay were adopted to examine cell viability. Apoptosis was analyzed using Annexin V-PE/7-amino-actinomycin D staining. Changes in plasma membrane permeability were monitored by FD500-uptake and lactate dehydrogenase (LDH) release assays. Additionally, the ultrastructure changes were evaluated under scanning electron microscope (SEM).
  
  
  RESULTS
  When 5 ng/ml PTX was combined with sonication at Load Power (LP) = 2 W, the expected synergistic effects on cell viability loss (p < 0.05) and apoptosis enhancement could be significantly detected, the plasma membrane permeability showed the best response, and relatively serious cell damages were observed under SEM.
  
  
  CONCLUSIONS
  The interaction between these two therapies depended on specific parameter settings, such as PTX dose and ultrasound intensity. Under synergistic conditions, ultrasound significantly potentiated the efficacies of PTX, including cytotoxicity, apoptosis and cell damage induction, which may be due to the enhanced membrane permeability and the increased intracellular PTX level.
authors: Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, Ministry of Education, National Engineering Laboratory for Resource Developing of Endangered Chinese Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University , Xi'an, Shaanxi , China.
authors: Shuang
authors: S
authors: Yang
authors: Pan
authors: P
authors: Wang
authors: Xiaobing
authors: X
authors: Wang
authors: Kun
authors: K
authors: Zhang
authors: Xing
authors: X
authors: Zhang
authors: Quanhong
authors: Q
authors: Liu
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D018929:Cell Culture Techniques; D002462:Cell Membrane / Q000187:drug effects / Q000528:radiation effects / Q000648:ultrastructure; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D003131:Combined Modality Therapy; D005434:Flow Cytometry; D006801:Humans; D020014:K562 Cells; D064347:Microscopy, Electrochemical, Scanning; D008855:Microscopy, Electron, Scanning; D017239:Paclitaxel / Q000008:administration & dosage / Q000494:pharmacology*; D013016:Sound; D014464:Ultrasonic Therapy
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D017239:Paclitaxel