Anterior gradient-2 （AGR2） promotes tumor growth, cell migration and cellular transformation and its enhanced expression is almost completely restricted to malignant tissues, thus making AGR2 an interesting target f...Anterior gradient-2 （AGR2） promotes tumor growth, cell migration and cellular transformation and its enhanced expression is almost completely restricted to malignant tissues, thus making AGR2 an interesting target for the development of immunotherapeutic strategies. We investigated whether the AGR2 molecule comprises human leukocyte antigen （HLA）-A 0201-binding epitopes recognized by human cytotoxic T lymphocytes （CTLs）, which could be targeted in dendritic cell （DC）-based cancer immunotherapy against colorectal cancer （CRC）. We reviewed the sequence of AGR2 for peptides that could potentially bind to HLA-A 0201 with the aid of a computer-based program. Five candidate peptides with different binding scores were synthesized and tested. These peptides were then assessed for their immunogenicity to elicit specific immune responses mediated by CTLs in vitro by means of enzyme-linked immunospot assays and CTL assays. AGR2 was highly expressed in several CRC cell lines, including DK01, DLD1, KM 12C, HCT-8 and HT-29. DCs pulsed with AGR2-P2 （aa 11-19; LLVALSYTL） or AGR2-P4 （aa 127-135; RIMFVDPSL） generated potent CTLs that could lyse T2 cells pulsed with AGR2-P2 or AGR2-P4 and HLA-A0201＋ AGR2-positive CRC cell lines in a strong dose-dependent and HLA-A 0201-restricted manner. In conclusion, these novel epitopes derived from AGR2 protein may be attractive candidates for DC-based immunotherapy for CRC.展开更多
While ovarian cancer （OvCa） responds well to surgery and conventional chemotherapy, a high recurrence rate of advanced OvCa is observed. In this phase Ⅰ/Ⅱ study, 10 OvCa patients with minimal residual disease were...While ovarian cancer （OvCa） responds well to surgery and conventional chemotherapy, a high recurrence rate of advanced OvCa is observed. In this phase Ⅰ/Ⅱ study, 10 OvCa patients with minimal residual disease were treated with autologous dendritic cells （DCs） and IL-2 to evaluate the safety and feasibility of this therapeutic strategy and to characterize the antigen-specific immune alterations induced through this treatment. Approximately 4 months after initial debulking and chemotherapy, patients received two subcutaneous doses of autologous monocyte-derived DCs pulsed with autologous tumor lysate and keyhole limpet hemocyanin （KLH） at 4-week intervals. After each DC inoculation, low-dose （200 mlU） IL-2 was introduced for 14 consecutive days as an immune adjuvant. The vaccination was well tolerated. In three out of 10 patients, the inclusion status after the initial therapy showed the maintenance of complete remission （CR） after DC vaccination for 83, 80.9 and 38.2 months without disease relapse. One patient with stable disease （SD） experienced the complete disappearance of tumor after DC vaccination, and this status was maintained for 50.8 months until tumor recurrence. In two patients with partial response （PR） was not responding to DC vaccination and their disease recurred. In the three patients with disease free long-term survival, significant immune alterations were observed, including increased natural killer （NK） activity, IFN-γ-secreting T cells, immune-stimulatory cytokine secretion and reduced immune-suppressive factor secretion after DC vaccination. Thus, in patients with NED status and increased overall survival, DC vaccination induced tumor-related immunity, potentially associated with long-term clinical responses against OvCa.展开更多
文摘Anterior gradient-2 （AGR2） promotes tumor growth, cell migration and cellular transformation and its enhanced expression is almost completely restricted to malignant tissues, thus making AGR2 an interesting target for the development of immunotherapeutic strategies. We investigated whether the AGR2 molecule comprises human leukocyte antigen （HLA）-A 0201-binding epitopes recognized by human cytotoxic T lymphocytes （CTLs）, which could be targeted in dendritic cell （DC）-based cancer immunotherapy against colorectal cancer （CRC）. We reviewed the sequence of AGR2 for peptides that could potentially bind to HLA-A 0201 with the aid of a computer-based program. Five candidate peptides with different binding scores were synthesized and tested. These peptides were then assessed for their immunogenicity to elicit specific immune responses mediated by CTLs in vitro by means of enzyme-linked immunospot assays and CTL assays. AGR2 was highly expressed in several CRC cell lines, including DK01, DLD1, KM 12C, HCT-8 and HT-29. DCs pulsed with AGR2-P2 （aa 11-19; LLVALSYTL） or AGR2-P4 （aa 127-135; RIMFVDPSL） generated potent CTLs that could lyse T2 cells pulsed with AGR2-P2 or AGR2-P4 and HLA-A0201＋ AGR2-positive CRC cell lines in a strong dose-dependent and HLA-A 0201-restricted manner. In conclusion, these novel epitopes derived from AGR2 protein may be attractive candidates for DC-based immunotherapy for CRC.
文摘While ovarian cancer （OvCa） responds well to surgery and conventional chemotherapy, a high recurrence rate of advanced OvCa is observed. In this phase Ⅰ/Ⅱ study, 10 OvCa patients with minimal residual disease were treated with autologous dendritic cells （DCs） and IL-2 to evaluate the safety and feasibility of this therapeutic strategy and to characterize the antigen-specific immune alterations induced through this treatment. Approximately 4 months after initial debulking and chemotherapy, patients received two subcutaneous doses of autologous monocyte-derived DCs pulsed with autologous tumor lysate and keyhole limpet hemocyanin （KLH） at 4-week intervals. After each DC inoculation, low-dose （200 mlU） IL-2 was introduced for 14 consecutive days as an immune adjuvant. The vaccination was well tolerated. In three out of 10 patients, the inclusion status after the initial therapy showed the maintenance of complete remission （CR） after DC vaccination for 83, 80.9 and 38.2 months without disease relapse. One patient with stable disease （SD） experienced the complete disappearance of tumor after DC vaccination, and this status was maintained for 50.8 months until tumor recurrence. In two patients with partial response （PR） was not responding to DC vaccination and their disease recurred. In the three patients with disease free long-term survival, significant immune alterations were observed, including increased natural killer （NK） activity, IFN-γ-secreting T cells, immune-stimulatory cytokine secretion and reduced immune-suppressive factor secretion after DC vaccination. Thus, in patients with NED status and increased overall survival, DC vaccination induced tumor-related immunity, potentially associated with long-term clinical responses against OvCa.
