Potential use of drug carried-liposomes for cancer therapy via direct intratumoral injection.
Liposomes have recognized advantages as nano-particle drug carriers for tumor therapy. In this study, the pharmacokinetics and distribution of intratumorally administered liposomes were investigated as drug carriers for treating solid tumors via direct intratumoral administration. 99mTc-liposomes were administered intratumorally to nude rats bearing human head and neck squamous cell carcinoma xenografts. Planar gamma camera images were analyzed to evaluate the local retention of the intratumorally administered liposomes. Co-registered pinhole micro-single photon emission computed tomography (SPECT)/computed tomography (CT) images were acquired of the whole animal as well as the dissected tumors to determine intratumoral distribution of the 99mTc-liposomes. For 99mTc-liposomes, there was an initial retention of 47.4 +/- 11.0% (n = 4) in tumors and surrounding tissues. At 20 h, 39.2 +/- 10.6% (n = 4) of 99mTc-activity still remained in the tumor. In contrast, only 18.7 +/- 3.3% (n = 3) of the intratumoral 99mTc-activity remained for unencapsulated 99mTc-complex at 20 h. Pinhole micro-SPECT images demonstrated that 99mTc-liposomes also have a superior intratumoral 99mTc-activity diffusion compared with unencapsulated 99mTc-complex. Higher intratumoral retention of 99mTc-liposomes accompanied by an improved intratumoral diffusion suggests that intratumorally administered liposomal drugs are potentially promising agents for solid tumor local therapy.
Department of Otolaryngology - Head and Neck Surgery, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA. bao@uthscsa.edu
Ande
A
Bao
William T
WT
Phillips
Beth
B
Goins
Xiangpeng
X
Zheng
Sarmad
S
Sabour
Mohan
M
Natarajan
F
F
Ross Woolley
Cristina
C
Zavaleta
Randal A
RA
Otto
D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D015552:Injections, Intralesional; D008081:Liposomes; D008297:Male; D049329:Nanostructures; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism; D051381:Rats; D011923:Rats, Nude; D013667:Technetium; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon; D023041:Xenograft Model Antitumor Assays
D000970:Antineoplastic Agents; D008081:Liposomes; D013667:Technetium