title: Paclitaxel loading in PLGA nanospheres affected the in vitro drug cell accumulation and antiproliferative activity.
abstract: BACKGROUND
  PTX is one of the most widely used drug in oncology due to its high efficacy against solid tumors and several hematological cancers. PTX is administered in a formulation containing 1:1 Cremophor EL (polyethoxylated castor oil) and ethanol, often responsible for toxic effects. Its encapsulation in colloidal delivery systems would gain an improved targeting to cancer cells, reducing the dose and frequency of administration.
  
  
  METHODS
  In this paper PTX was loaded in PLGA NS. The activity of PTX-NS was assessed in vitro against thyroid, breast and bladder cancer cell lines in cultures. Cell growth was evaluated by MTS assay, intracellular NS uptake was performed using coumarin-6 labelled NS and the amount of intracellular PTX was measured by HPLC.
  
  
  RESULTS
  NS loaded with 3% PTX (w/w) had a mean size < 250 nm and a polydispersity index of 0.4 after freeze-drying with 0.5% HP-Cyd as cryoprotector. PTX encapsulation efficiency was 30% and NS showed a prolonged drug release in vitro. An increase of the cytotoxic effect of PTX-NS was observed with respect to free PTX in all cell lines tested.
  
  
  CONCLUSIONS
  These findings suggest that the greater biological effect of PTX-NS could be due to higher uptake of the drug inside the cells as shown by intracellular NS uptake and cell accumulation studies.
authors.affiliation: Dipartimento di Oncologia Sperimentale, Istituto Oncologico del Mediterraneo, Viagrande (CT), Italy. l.vicari@iomricerca.it
authors.forename: Luisa
authors.initials: L
authors.lastname: Vicari
authors.forename: Teresa
authors.initials: T
authors.lastname: Musumeci
authors.forename: Ignazio
authors.initials: I
authors.lastname: Giannone
authors.forename: Luana
authors.initials: L
authors.lastname: Adamo
authors.forename: Concetta
authors.initials: C
authors.lastname: Conticello
authors.forename: Ruggero
authors.initials: R
authors.lastname: De Maria
authors.forename: Rosario
authors.initials: R
authors.lastname: Pignatello
authors.forename: Giovanni
authors.initials: G
authors.lastname: Puglisi
authors.forename: Massimo
authors.initials: M
authors.lastname: Gulisano
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002470:Cell Survival; D002851:Chromatography, High Pressure Liquid; D003102:Colloids / Q000737:chemistry; D003374:Coumarins / Q000737:chemistry / Q000378:metabolism; D004337:Drug Carriers / Q000493:pharmacokinetics; D019337:Hematologic Neoplasms / Q000188:drug therapy / Q000473:pathology; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods; D009369:Neoplasms / Q000188:drug therapy*; D017239:Paclitaxel / Q000008:administration & dosage*; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D003102:Colloids; D003374:Coumarins; D004337:Drug Carriers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C030123:coumarin; D017239:Paclitaxel