You Ichinose

Cyclophosphamide given after active specific immunization augments antitumor immunity by modulation of Th1 commitment of CD4+ T cells.

Background and Objectives: In order to evaluate the regulatory effect of cyclophosphamide (CPA) on active specific immunization (ASI)‐induced antitumor immunity, we examined the timing of CPA (100 mg/kg) with ASI, and focused on whether CPA given after ASI augments antitumor immunity by modulation of Th1 commitment of CD4+ T cells.

Relationship between immunological parameters and survival of patients with liver metastases from breast cancer given immuno-chemotherapy

SummaryWe treated 33 patients with liver metastases from breast cancer by immuno-chemotherapy including adoptive cell transfer between 1987 and 1992. In this study, we examined the change of immunological parameters in the peripheral blood lymphocytes and interleukin-2 (IL-2)-cultured lymphocytes, in primary vs. metastatic breast cancer patients and before vs. after treatment. Moreover, we examined their correlation with therapeutic response and survival after treatment. The immunological parameters used werein vitro natural killer cell activity (% lysis of K562),in vitro autologous tumor-killing activity (% lysis against autologous freshly isolated tumor cells), and proliferation of lymphocytes stimulated with IL-2 and autologous sonicated tumor extract antigen in mixed culture (IL-2-enhanced MLTR). When compared with primary breast cancer patients, patients with liver metastases showed a significant decrease in % lysis of K562 and autologous tumor cells. After treatment, the stimulation index in IL-2-enhanced MLTR increased significantly from the pretreatment level and correlated with survival after treatment. Moreover, non-specific immunological parameters (performance status, lymphocyte count, and transferred cell count and proliferation rate of cultured lymphocytes) were significantly associated with response and prognosis.

The Induction of Specific Antitumor Immunity by In Vivo Treatment with Interleukin-1 and Sonicated Tumor Extract in a Murine Model

BALB/c mice were pretreated intraperitoneally with interleukin-1 (IL-1) and sonicated tumor extract (SE) from plasmacytoma MOPC104E, 10, 7, and 4 days prior to the intraperitoneal or subcutaneous inoculation of MOPC104E cells, following which significant suppression was observed. The mean survival time and tumor diameter on day 21 were 46.7 days and 0 mm, respectively, in contrast to the 20.9 days and 20.4 mm of control mice. Mice pretreated with IL-1 and SE from MOPC104E (MOPC-SE) were not suppressed following fibrosarcoma MethA inoculation, which indicates the tumor specificity of immunity in this model. This systemically operating antitumor immunity was also achieved by the intramuscular administration of IL-1, or when tumor challenge was performed on day 7 or 14. Moreover, MOPC104E-specific delayed-type hypersensitivity was detected in these mice. The results of this study suggest the possibilities of a new type of active specific immunotherapy, which could prove useful as postsurgical adjuvant therapy for cancer patients.

A new model of active specific immunotherapy using interleukin-1 and sonicated tumor supernatant in murine tumor system

The possibility of active specific immunotherapy using interleukin‐1 (IL‐1) plus sonicated tumor supernatant (SS) was examined in a murine tumor model. The growth of intraperitoneally or subcutaneously inoculated plasmacytoma MOPC104E, which is syngeneic to BALB/c mice, was significantly suppressed by intraperitoneal pretreatment with IL‐1 and SS from MOPC104E cells (MOPC‐SS), on days 10, 7, and 4 before tumor inoculation. Pretreatment with IL‐1 plus MOPC‐SS or MethA‐SS (SS from MethA cells) suppressed the growth of subcutaneous tumor of only the corresponding tumor cells, indicating the development of tumor‐specific immunity in vivo. The splenic cells of immunized mice with IL‐1 and MOPC‐SS showed tumor neutralizing activity. However, their tumor neutralizing activity was abrogated when they were treated in vitro with anti‐Thy1.2 or anti‐L3T4 plus complement. Moreover, when combined with indomethacin per oral, IL‐1 plus MOPC‐SS significantly suppressed the growth of established subcutaneous tumor and prolonged survival of postoperative mice. These results suggest that this new type of active specific immunotherapy could be a useful method for cancer immunotherapy, especially when combined with oral indomethacin.

Laparoscopic total gastrectomy for multiple sporadic gastric gastrointestinal stromal tumors: report of a case

A 64-year-old man was admitted to our hospital with hematemesis. Emergency upper gastrointestinal endoscopy revealed bleeding from a submucosal tumor (SMT) in the antrum of the stomach, with two other SMTs at different sites. Based on his family history, we diagnosed familial multiple gastric gastrointestinal stromal tumors (GISTs) and performed laparoscopic total gastrectomy. Three distinct tumors were found: one in the fornix, one in the lesser curvature of the angle, and one in the antrum of the stomach. Microscopic examination of the resected specimens revealed different cytomorphologies, of the spindle and epithelioid type, as well as immunophenotypes in the tumors. Mutation analysis revealed different sites of mutation in c-kit and PDGFRA. No mutation was detected in the normal tissue of the stomach. These findings confirmed a diagnosis of multiple sporadic gastric GISTs. Thus, investigating germline mutation might assist in the preoperative diagnosis of multiple gastric GISTs.

Cellular interaction against autologous tumor cells between IL-2-cultured lymphocytes and fresh peripheral blood lymphocytes in patients with breast cancer given immuno-chemotherapy

In patients with Stage II or III breast cancer and in patients with liver metastases from breast cancer, we examined cellular interaction in the cytotoxicity against autologous tumor cells by interleukin-2(IL-2)-cultured lymphocytes (CL) and fresh peripheral blood lymphocytes (FPBL) treated with immunochemotherapy including OK-432 and cyclophosphamide. In flow cytometric analysis, CD8 + CD11b+ and CD16+ cells significantly decreased after immuno-chemotherapy in both groups of patients. A protocol study in Stage II or III breast cancer patients showed suppressive activity of FPBL on the cytotoxic activity of CL in 3/9 of the non-treatment group but no suppressive activity and enhancing activity in 3/7 in the immuno-chemotherapy group. Moreover, in 19 patients with liver metastases from breast cancer treated with immuno-chemotherapy including adoptive immunotherapy, FPBL in 6/19 showed enhancing activity, and in 8/19 suppressive activity in the lysis of autologous tumor cells. In assaysin vitro using autologous and allogeneic tumor cells, FPBL showed a partial specificity in cellular interaction against autologous tumor cells. CD4-depleted FPBL inhibited cytotoxicity of CL, while CD8-depleted FPBL enhanced cytotoxicity of CL in patients with liver metastases. These results suggest that immuno-chemotherapy eliminates the suppressive population in FPBL and may induce tumor regression if combined with adoptive immunotherapy using CL.

OK-432-combined adoptive immunotherapy as a prognostic factor in peritoneal metastasis from gastric cancer

Prognostic factors, such as preoperative status, intraoperative findings, and postoperative treatments, were evaluated in 61 patients with peritoneal metastasis from gastric cancer treated in our facility between 1979 and 1991. Since 1986, 23 patients have been treated with OK-432-combined adoptive immunotherapy (AIT). OK-432-combined AIT is a sequential treatment via a catheter inserted into the abdominal cavity, using a streptococcal preparation, OK-432, followed by the transfer of lymphocytes cultured with T cell growth factor and sonicated tumor extract. A univariate analysis showed that six factors consisting of: (1) age, (2) resection of primary lesion, (3) grade of peritoneal metastasis or serosal invasion, (4) chemotherapy, (5) OK-432, and (6) OK-432-combined AIT influenced survival. The survival of the patients given OK-432-combined AIT (median survival time; MST = 7.5 months) was significantly (P = 0.0267) longer than that of those not receiving OK-432-combined AIT (MST = 4.3 months). A multivariate analysis showed that the most significant factors associated with survival were chemotherapy, resection of the primary lesion, and OK-432-combined AIT. Since these three factors are all therapeutic procedures, the use of combination therapy including OK-432-combined AIT is thus expected to prolong the survival of gastric cancer patients with peritoneal metastasis.

Analysis of effector cells in tumor-bearing mice pre-treated with active specific immunization followed by cyclophosphamide

In order to analyse the effector population in an immunization model, we treated BALB/c mice with intraperitoneal (i.p.) active specific immunization (ASI), which consists of interleukin (IL)-1-β and sonicated tumor supernatant (SS) of a plasmacytoma MOPC-104E followed by i.p. injection of cyclophosphamide (CY). This ASI-CY treatment provoked a protective immunity against i.p. tumor inoculation more strongly than that of ASI alone. The main effector cells in tumor neutralizing assay were CD4+ T cells at this pont. The number of spleen cells of the ASI-CY treated mice were significantly lower than that of ASI alone treated mice but it increased significantly 6 days thereafter while this increase was not observed on the mice treated with ASI alone. The spleen cells of the ASI-CY treated mice responded to SS in vitro in the presence of IL-2, more profoundly in CD4 enriched population which produced high amount of TNF-α. In vivo tumor-neutralizing activity at a later stage was dependent on CD8+ T cells in addition to CD4+ T cells. These results suggest that antitumor activity by ASI and CY is transduced by sequential population shift from CD4 alone to both of CD4 and CD8.

Reduction of tumorigenicity by an interferon-gamma-gene-transduced tumor on another syngeneic tumor in a murine model

To evaluate the effect of interferon-γ-genetransduced cells, DS mice were inoculated into their footpads with syngeneic mammary adenocarcinoma SC42 admixed with interferon-γ producing mammary adenocarcinoma SC115Kγ, which had been established by an interferon-γ-gene transduction in another syngeneic mammary adenocarcinoma SC115 using retroviral vectors. These mice rejected both tumor cells and developed resistance to subsequent challenges with either SC115 or SC42 cells inoculated into their opposite posterior footpads. These results thus indicate that systemic immunological memory to each of the independent tumor cell lines developed in these mice. Although the SC42 cells admixed with irradiated SC115Kγ cells were rejected by these mice, the SC42 cells admixed with irradiated SC115neoR, in which the neo-gene had been transduced, were observed to proliferate. Tumor rejection was reversed by an in vivo administration of anti-interferon-γ antibody, thus suggesting that locally produced interferon-γ plays an important role in tumor elimination and immunological memory induction. In conclusion, interferon-γ-gene-transduced tumor cells are therefore considered to have a therapeutic potential for other types of malignant tumor cell lines.

The effectiveness of active specific immunotherapy using interferon-γ-gene-transduced tumor cells in a murine tumor model

Active specific immunotherapy was examined in BALB/c mice using sonicated tumor extract(SE) from plasmacytoma MOPC104E or interferon-γ-(IFN-γ)-genetransduced MOPC104E (Muγ), employing interleukin-1 (IL-1) as an adjuvant. Subcutaneous(s.c.) MOPC104E tumor growth was significantly suppressed in mice given a single preimmunization of IL-1 plus Muγ-SE, 9 days prior to inoculation, whereas the tumor growth in mice similarly pretreated with IL-1 alone or IL-1 plus MOPC104E-SE(MOPC-SE) was not affected; the mean tumor diameters on day 21 being 6.8mm, 15.3mm, and 13.2mm, respectively. Two-dose preimmunization with Muγ-SE alone or IL-1 alone given 10 and 7 days prior to s.c. inoculation also resulted in profound suppression of tumor growth compared to the control. As postsurgical immunization, MOPC104E cells were injected into the foot pads of mice, followed by amputation of the tumor-bearing foot 20 days later, then treatment with IL-1 plus MOPC-SE or IL-1 plus Muγ-SE on days 4, 7, and 10 after the amputation. The mean survival of the mice treated with IL-1 plus Muγ-SE was significantly prolonged compared to that of the mice treated with IL-1 plus MOPC-SE, at 90.3 daysvs 40.9 days, respectively (P<0.05 by the Cox-Mantel test). These results suggest that SE prepared from IFN-γ-genetransduced MOPC104E is more effective for active specific immunotherapy than SE prepared from MOPC104E.