Control of cervicovaginal HPV-16 E7-expressing tumors by the combination of therapeutic HPV vaccination and vascular disrupting agents.
Abstract Antigen-specific immunotherapy and vascular disrupting agents, such as 5,6-dimethylxanthenone-4-acetic acid (DMXAA), have emerged as attractive approaches for the treatment of cancers. In the current study, we tested the combination of DMXAA treatment with therapeutic human papillomavirus type 16 (HPV-16) E7 peptide-based vaccination for their ability to generate E7-specific CD8+ T-cell immune responses, as well as their ability to control E7-expressing tumors in a subcutaneous and a cervicovaginal tumor model. We found that the combination of DMXAA treatment with E7 long peptide (amino acids 43-62) vaccination mixed with polyriboinosinic:polyribocytidylic generated significantly stronger E7-specific CD8+ T-cell immune responses and antitumor effects compared with treatment with DMXAA alone or HPV peptide vaccination alone in the subcutaneous model. Additionally, we found that the DMXAA-mediated enhancement of E7-specific CD8+ T-cell immune responses generated by the therapeutic HPV peptide-based vaccine was dependent on the timing of administration of DMXAA. Treatment with DMXAA in tumor-bearing mice was also shown to lead to increased dendritic cell maturation and increased production of inflammatory cytokines in the tumor. Furthermore, we observed that the combination of DMXAA with HPV-16 E7 peptide vaccination generated a significant enhancement in the antitumor effects in the cervicovaginal TC-1 tumor growth model, which closely resembles the tumor microenvironment of cervical cancer. Taken together, our data demonstrated that administration of the vascular disrupting agent, DMXAA, enhances therapeutic HPV vaccine-induced cytotoxic T-lymphocyte responses and antitumor effects against E7-expressing tumors in two different locations. Our study has significant implications for future clinical translation.
Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China 200433.
Qi
Q
Zeng
Shiwen
S
Peng
Archana
A
Monie
Ming
M
Yang
Xiaowu
X
Pang
Chien-Fu
CF
Hung
T-C
TC
Wu
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D052162:Human papillomavirus 16 / Q000235:genetics / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D050725:Papillomavirus E7 Proteins / Q000235:genetics* / Q000276:immunology; D053918:Papillomavirus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D059016:Tumor Microenvironment; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D044004:Xanthones / Q000627:therapeutic use
D000970:Antineoplastic Agents; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines; D044004:Xanthones; C059731:oncogene protein E7, Human papillomavirus type 16; C066668:vadimezan