Microbubble therapy enhances anti-tumor properties of cisplatin and cetuximab in vitro and in vivo.
OBJECTIVE
To determine if microbubble-mediated ultrasound therapy (MB-UST) can improve cisplatin or cetuximab cytotoxicity of head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo by increasing tumor-specific drug delivery by disruption of tumor cell membranes and enhancing vascular permeability.


METHODS
In vitro and in vivo study.


METHODS
University medical center.


METHODS
Immunodeficient mice (6 weeks old) and 4 HNSCC cell lines.


METHODS
Changes to cell permeability were assessed in vitro after MB-UST. Cellular apoptosis resulting from adjuvant MB-UST with subtherapeutic doses of cisplatin or cetuximab was assessed by cell survival assays in vitro. The in vivo effect of adjuvant MB-UST in flank tumors was assessed in vivo with histological analysis and diffusion-weighted magnetic resonance imaging (DW-MRI).


RESULTS
In vitro results revealed that MB-UST can increase cell permeability and enhance drug uptake and apoptosis in 4 HNSCC cell lines. In vivo adjuvant MB-UST with cetuximab or cisplatin showed a statistically significant reduction in tumor size when compared with untreated controls. TUNEL analysis yielded a larger number of cells undergoing apoptosis in tumors treated with cetuximab and adjuvant MB-UST than did cetuximab alone but was not significantly greater in tumors treated with cisplatin and adjuvant MB-UST compared with cisplatin alone. DW-MRI analysis showed more free water, which corresponds to increased cell membrane disruption, in tumors treated with MB-UST.


CONCLUSIONS
MB-UST promotes disruption of cell membranes in tumor cells in vitro, which may be leveraged to selectively improve the uptake of conventional and targeted therapeutics in vivo.
Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Cara H
CH
Heath
Anna
A
Sorace
Joseph
J
Knowles
Eben
E
Rosenthal
Kenneth
K
Hoyt
D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000628:therapy*; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D000068818:Cetuximab; D002945:Cisplatin / Q000008:administration & dosage*; D005260:Female; D006258:Head and Neck Neoplasms / Q000473:pathology / Q000628:therapy*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D045423:Microbubbles; D010539:Permeability / Q000187:drug effects; D000077195:Squamous Cell Carcinoma of Head and Neck; D014464:Ultrasonic Therapy
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000068818:Cetuximab; D002945:Cisplatin