Effects of adoptive T-cell immunotherapy on immune cell profiles and prognosis of patients with unresectable or recurrent cholangiocarcinoma.

The identification of immune cell profiles (ICP) involved in anti-tumor immunity is crucial for immunotherapy. Therefore, we herein investigated cholangiocarcinoma patients (CCA) who received adoptive T-cell immunotherapy (ATI). Eighteen unresectable or recurrent CCA received ATI of αß T cells alone or combined with chemotherapy. ICP were evaluated by flow cytometry. There were 14 patients with intrahepatic cholangiocarcinoma (iCCA) and four with distal cholangiocarcinoma (dCCA). After one course of treatment, nine iCCA and four dCCA had progressive disease (PD), while five iCCA had stable disease (SD). Median overall survival (OS) was prolonged to 21.9 months. No significant differences were observed in OS between the PD and SD groups of iCCA. The frequency of helper T cells (HT) in iCCA decreased from 70.3% to 65.5% (P = .008), while that of killer T cells (KT) increased from 27.0% to 30.6% (P = .005). dCCA showed no significant changes of immune cells. OS was prolonged in iCCA with increased frequencies of CD3+ T cells (CD3) (P = .039) and αß T cells (αß) (P = .039). dCCA showed no immune cells associated with OS. The frequencies of CD3+ T cells and αß T cells in the PD group for iCCA decreased from 63.5% to 53% (P = .038) and from 61.6% to 52.2% (P = .028), respectively. In the SD group, the frequency of HT decreased from 65.8% to 56.9% (P = .043), whereas that of KT increased from 30.1% to 38.3% (P = .043). In conclusions, ATI affected ICP and prolonged OS. Immune cells involved in treatment effects differed according to the site of cholangiocarcinoma.

Safety evaluation of immune-cell therapy for malignant tumor in the Cancer Immune-cell Therapy Evaluation Group (CITEG).

BACKGROUND AIMS: With the aim of strengthening the scientific evidence of immune-cell therapy for cancer and further examining its safety, in October 2015, our hospital jointly established the Cancer Immune-Cell Therapy Evaluation Group (CITEG) with 39 medical facilities nationwide. METHODS: Medical information, such as patients' background characteristics, clinical efficacy and therapeutic cell types obtained from each facility, has been accumulated, analyzed and evaluated by CITEG. In this prospective study, we analyzed the adverse events associated with immune-cell therapy until the end of September 2022, and we presented our interim safety evaluation. RESULTS: A total of 3839 patients with malignant tumor were treated with immune-cell therapy, with a median age of 64 years (range, 13-97 years) and a male-to-female ratio of 1:1.08 (1846:1993). Most patients' performance status was 0 or 1 (86.8%) at the first visit, and 3234 cases (84.2%) were advanced or recurrent cases, which accounted for the majority. The total number of administrations reported in CITEG was 31890, of which 960 (3.0%) showed adverse events. The numbers of adverse events caused by treatment were 363 (1.8%) of 19661 administrations of αßT cell therapy, 9 of 845 administrations of γδT-cell therapy (1.1%) and 10 of 626 administrations of natural killer cell therapy (1.6%). The number of adverse events caused by dendritic cell (DC) vaccine therapy was 578 of 10748 administrations (5.4%), which was significantly larger than those for other treatments. Multivariate analysis revealed that αßT cell therapy had a significantly greater risk of adverse events at performance status 1 or higher, and patients younger than 64 years, women or adjuvant immune-cell therapy had a greater risk of adverse events in DC vaccine therapy. Injection-site reactions were the most frequently reported adverse events, with 449 events, the majority of which were associated with DC vaccine therapy. Among all other adverse events, fever (228 events), fatigue (141 events) and itching (131 events) were frequently reported. In contrast, three patients had adverse events (fever, abdominal pain and interstitial pneumonia) that required hospitalization, although they were weakly related to this therapy; rather, it was considered to be the effect of treatment for the primary disease. CONCLUSIONS: Immune-cell therapy for cancer was considered to be a safe treatment without serious adverse events.

Effect of adoptive T-cell immunotherapy on immunological parameters and prognosis in patients with advanced pancreatic cancer.

BACKGROUND AIMS: Immunotherapy is effective for many types of cancer, but its benefits in advanced pancreatic cancer, which has a poor prognosis, are not well established. In this study, the authors examined the effects of adoptive T-cell immunotherapy (ATI) on immune cell profiles and prognosis in patients with unresectable advanced pancreatic cancer. METHODS: Seventy-seven patients with unresectable advanced pancreatic cancer were treated with six cycles of αß T cells alone or in combination with chemotherapy or chemoradiation. Immune cell profiles in peripheral blood samples obtained before and after treatment were comprehensively evaluated by flow cytometry. Furthermore, associations between changes in immune cell frequencies and prognosis were determined. RESULTS: ATI prolonged survival to 18.7 months compared with previous estimates of 6.2-11.1 months for patients treated with chemotherapy alone. ATI decreased CD3+CD4+CD8- T cell frequency in peripheral blood and increased CD3+CD4-CD8+ T cell frequency. An increase in CD3+ T cells and CD3+TCRγδ- T cells in peripheral blood after treatment was associated with a good prognosis. CONCLUSIONS: ATI altered the immune profile in peripheral blood, including CD3+CD4-CD8+ T cells, and improved prognosis in pancreatic cancer.

Identification of prognostic factors for γδT cell immunotherapy in patients with solid tumor.

BACKGROUND AIMS: Activated γδT cells have been shown to exhibit cytotoxicity against tumor cells. However, the efficacy of γδT cell immunotherapy for a large number of patients with solid tumors remains unclear. In this study, we examined the efficacy of γδT cell immunotherapy using in vitro-activated γδT lymphocytes in combination with standard therapies in terms of the survival of patients with solid tumors, and determined prognostic factor for γδT cell immunotherapy. METHODS: 131 patients enrolled in this study received γδT cell immunotherapy with or without standard therapies. Their overall survival was analyzed by the Kaplan-Meier with log-rank test and Cox regression methods. Immunological analysis was performed by flow cytometry (FCM) before and after six cycles of γδT cell immunotherapy. RESULTS: Multivariable analysis revealed that patients who showed stable disease (SD) and partial response (PR) to γδT cell immunotherapy showed better prognosis than those with a progressive disease (PD) (P = 0.0269, hazard ratio [HR], 0.410, 95% confidence interval [CI], 0.190-0.901). Furthermore, when immunological parameters were examined by FCM, the high Vγ9/γδT ratio (i.e., the high purity of the Vγ9 cells within the adoptively transferred γδT cells) before treatment was found to be a good prognostic factor for γδT cell immunotherapy (P = 0.0142, HR, 0.328, 95% CI, 0.125-0.801). No serious adverse events were reported during γδT cell immunotherapy. CONCLUSION: Thus, γδT cell immunotherapy might extend the survival of patients with solid tumors.

Dendritic cell vaccines loaded with autologous tumor lysates for solid tumors.

Recently, immunotherapy has been utilized as a novel option for the treatment of various malignancies, however, it is necessary to develop immune cell therapy on the basis of the blockade of immune checkpoints, antigen presentation on dendritic cell (DC) vaccines and the high avidity tumor reactive T cells. Autologous tumor lysate-loaded DC vaccines could have a potency to elicit T cells immune response with both epitopes of neoantigen and com- mon antigen; however the innate immunity should be essential for the cross-presentation process. Furthermore, DC vaccines loaded with tumor lysates by electroporation system eli- cited both antigen-specific CD8 and CD4 T cells. In order to break the immunosuppression, the combined therapy of the tumor lysate-loaded DC vaccines and immune checkpoint inhib- itors should be investigated in the future.

A pilot study on the safety and efficacy of neoadjuvant chemo­adoptive immunotherapy for locally advanced rectal cancer.

The safety and efficacy of combination therapy of immune cell therapy and chemotherapy [chemo-adoptive immunotherapy (CAIT)] for patients with stage IV or recurrent colorectal cancer have been reported. In the present study, the safety and efficacy of neoadjuvant CAIT were investigated for preoperative therapy of locally advanced rectal cancer. The study included patients with cT3/T4 or cN (+) rectal adenocarcinoma scheduled for curative surgery. Six patients who consented to participate in the current study were selected as subjects. Neoadjuvant CAIT involves administration of activated autologous lymphocytes, αß T cells, and mFOLFOX6 every 2 weeks for six courses, followed by surgery 4-6 weeks thereafter. Common Terminology Criteria for Adverse Events grade 3 neutropenia was observed in one patient. Neoadjuvant CAIT and curative surgery were performed on all the patients. The confirmed response rate was 67%. Downstaging was confirmed in five patients (83%). Regarding histological effects, two patients were grade 1a and four were grade 2. Regarding immunological reactions, both CD4+ and CD8+ T cell infiltration rates increased after treatment in three patients on tumor-infiltrating lymphocyte (TIL) analysis. In peripheral blood analysis, the total lymphocyte count was maintained in all patients, and the CD8+ T cell count increased by ≥3 times on the pretreatment count in two patients but may not be associated with changes in TILs. During the median postoperative follow-up duration of 24 months, liver and lung metastases occurred in one patient, but all patients survived. In conclusion, neoadjuvant CAIT (αß T cells + mFOLFOX6) can be safely administered for the treatment of advanced rectal cancer. Verification of the efficacy of comprehensive immune cell therapy, especially the induction of antitumor immunity for the prevention of recurrence, will be maintained. The current study is registered with the Japan Registry of Clinical Trials (jRCT; ID, jRCTc030190248; January 21, 2019).

Rab27a negatively regulates phagocytosis by prolongation of the actin-coating stage around phagosomes.

Rab27a, a Rab family small GTPase, is involved in the exocytosis of secretory granules in melanocytes and cytotoxic T-cells. Rab27a mutations cause type 2 Griscelli syndrome, which is characterized by immunodeficiency, including uncontrolled macrophage activation known as hemophagocytic syndrome. However, the role of Rab27a in phagocytosis remains elusive. Here, using macrophage-like differentiated HL-60 cells and C3bi-opsonized zymosan as a pathogen-phagocyte model, we show that Rab27a negatively regulates complement-mediated phagocytic activity in association with F-actin remodeling. We found that transfection of Rab27a shRNA into HL-60 cells enhances complement-mediated phagocytosis. To clarify the mechanisms underlying the elevated phagocytosis in Rab27a knockdown cells, we analyzed the process of phagosome formation focusing on F-actin dynamics: F-actin assembly, followed by F-actin extension around the particles and the subsequent degradation of F-actin, leading to internalization of the particles enclosed in phagosomes. Microscopic analysis revealed that these actin-related processes, including F-actin coating and F-actin degradation, proceed more rapidly in Rab27a knockdown cells than in control HL-60 cells. Both elevated phagocytosis and accelerated F-actin remodeling were restored by expression of rescue-Rab27a and Rab27a-Q78L (GTP-bound form), but not by Rab27a-T23N (GDP-bound form). Furthermore, an increased accumulation of Coronin 1A surrounding F-actin coats was observed in Rab27a knockdown cells, suggesting that the function of Coronin 1A is related to the regulation of the F-actin coating. Our findings demonstrate that Rab27a plays a direct regulatory role in the nascent process of phagocytosis by prolongation of the stage of actin coating via suppression of Coronin 1A. This study may contribute to an explanation of the underlying mechanisms of excessive phagocytosis observed in Griscelli syndrome.

Extended survival observed in adoptive activated T lymphocyte immunotherapy for advanced lung cancer: results of a multicenter historical cohort study.

PURPOSE: To clarify the long-term effect of immunotherapy, the effect of adoptive activated T lymphocyte immunotherapy on advanced lung cancer was evaluated in terms of survival time. In addition, the performance status of cancer patients under immunotherapy was examined. EXPERIMENTAL DESIGN: Over 5 × 10(9) alpha-beta T lymphocytes cultured ex vivo with an immobilized anti-CD3 antibody and interleukin-2 were injected intravenously into patients, once every 2 weeks for 3 months or longer. Follow-up of these patients was carried out using clinical records and by telephone interview questionnaire. Patients undergoing immunotherapy in immunotherapy clinics and those undergoing other anticancer therapies without immunotherapy in seven hospitals in Tokyo were enrolled in this study. Data were analyzed by a third-party statistician. Performance status was studied on another series of various cancer patients who underwent immunotherapy. RESULTS: The overall median survival time of the patients with the best supportive care, which was obtained using Kaplan-Meier's model, was 5.6 months, and those with immunotherapy alone, chemotherapy alone, and immuno-chemotherapy were 12.5, 15.7, and 20.8 months, respectively. Using Cox' proportional hazard model, we examined the possible factors on survival time by univariate analysis. Then, the patients were stratified by gender and histological type for multivariate analysis. Significantly low hazard ratios were observed for immunotherapy and radiotherapy in males with squamous cancer; for chemotherapy and radiotherapy in male with adenocarcinoma; and for immunotherapy in females with adenocarcinoma. Addition of immunotherapy to chemotherapy resulted in a statistically significant decrease in hazard ratio in females with adenocarcinoma. Studies on the performance status (PS), determined according to the European Cooperative Oncology Group criteria, revealed a continuous high level of PS under immunotherapy until around 2 months before death, in contrast to the gradual increase of tumor marker level. CONCLUSIONS: The effectiveness of immunotherapy on advanced lung cancer is limited but may extend life span under certain conditions. Immunotherapy itself provided no clinical benefit by itself as compared with chemotherapy, but a significant additive effect of immunotherapy on chemotherapy was observed in females with adenocarcinoma. Moreover, immunotherapy can maintain good quality of life of the patients until near the time of death.

Efficacy of Adjuvant Immune-cell Therapy Combined With Systemic Therapy for Solid Tumors.

BACKGROUND/AIM: The efficacy of adjuvant systemic therapy after surgical resection remains unsatisfactory; therefore, a new treatment strategy is required. We aimed to examine the efficacy of adjuvant immune-cell therapy using activated T lymphocytes with or without dendritic cell vaccination in combination with standard adjuvant systemic therapies in terms of the survival of patients with solid tumors, such as lung, gastric, pancreatic, colorectal, and breast cancers. PATIENTS AND METHODS: A total of 141 patients with solid tumors were enrolled in this study. The correlation of overall survival and disease-free survival with various clinical factors such as age, sex, performance status score, clinical stage, treatment strategies, and vital status was investigated by univariate and multivariate analyses. RESULTS: Multivariate analysis revealed that a performance status score of 0 was a favorable prognostic factor in the full analysis set of solid tumors (HR=0.209, 95%CI=0.065-0.676, p=0.0089) and might be the indication for immune-cell therapy in the adjuvant setting. CONCLUSION: Adjuvant immune-cell therapy combined with other systemic therapies would potentially provide a survival benefit in patients with solid tumors.

Zoledronate-activated Vγ9γδ T cell-based immunotherapy is feasible and restores the impairment of γδ T cells in patients with solid tumors.

Gamma/delta (γδ) T cells play a role in innate immunity and exhibit cytotoxicity toward a large range of tumor types. Recent studies have shown that aminobisphosphonates may be applied to a culture in which a large number of γδ T cells are proliferated ex vivo. We carried out a clinical study of 25 patients with various solid tumors to determine further the safety, immunologic effect and feasibility of zoledronate-activated Vγ9γδ T cell-based immunotherapy. No severe toxicity was observed. In the cells used for the first treatment, the total cell number, frequency and number of CD3(+) Vγ9(+) γδ T cells were 409 ± 284 × 10(7) cells, 56 ± 33% and 255 ± 242 × 10(7) cells, respectively. Aminobisphosphonate therapy or chemotherapy resulted in the suppression of CD3(+) Vγ9(+) γδ T-cell proliferation. The numbers of CD3(+) T cells, CD3(+) Vγ9(+) γδ T cells and CD27(-) CD45RA(-) Vγ9(+) subsets in peripheral blood were significantly lower in patients than in healthy subjects (P < 0.05). From such an impaired immunologic condition, the numbers and frequencies of CD3(+) Vγ9(+) γδ T cells and CD27(-) CD45RA(-) subsets significantly increased in patients treated with this immunotherapy. Zoledronate-activated Vγ9γδ T cell-based immunotherapy that restores the number of Vγ9γδ T cells in cancer patients may provide another mode of adoptive immunotherapy.

Prognostic Factors for Advanced/Recurrent Breast Cancer Treated With Immune-cell Therapy.

BACKGROUND/AIM: Advanced/recurrent breast cancer (ARBC) still has a poor prognosis; therefore, new treatment strategies are required. In this retrospective study, we aimed to investigate the efficacy of immune-cell therapy using T lymphocytes activated in vitro with or without dendritic cell vaccination in combination with standard therapies in terms of the survival of patients with ARBC. PATIENTS AND METHODS: A total of 127 patients with ARBC were enrolled in this study. The correlation between overall survival and various clinical factors of each ARBC subset was examined by univariate and multivariate analyses. RESULTS: Multivariate analysis demonstrated that performance status (PS) 0, the absence of prior chemotherapy, liver/pleural metastasis, and the presence of combined surgery in ARBC and PS 0 or the absence of liver metastasis in the HR+/HER- subset are indications for immune-cell therapy. CONCLUSION: A survival benefit could be potentially obtained by a combination of immune-cell therapy with other therapies in ARBC patients.

Esophageal cancer responsive to the combination of immune cell therapy and low-dose nivolumab: two case reports.

BACKGROUND: Blocking the programmed death 1 pathway by immune checkpoint inhibitors induces dramatic antitumor activity in patients with malignant tumors. However, the clinical response to immune checkpoint inhibitors remains limited owing to the patients' immunological status, such as the number of lymphocytes, programmed death ligand 1 expression, and tumor mutation burden. In this study, we successfully treated two patients with advanced esophageal cancer who responded to the combination of adoptive immune cell therapy and a low-dose immune checkpoint inhibitor, nivolumab. CASE PRESENTATION: Two Asian (Japanese) patients with advanced esophageal cancer who were resistant to conventional chemoradiation therapy were referred to our hospital for immune therapy. Case 1 was a 66-year-old woman who was diagnosed as having esophageal cancer. She received concurrent chemoradiation therapy and then underwent subtotal esophagectomy, after which she became cancer free. However, she relapsed, and cancer cells were found in the lung and lymph nodes 6 months later. She enrolled in a clinical trial at our institution (clinical trial number UMIN000028756). She received adoptive immune cell therapy twice at a 2-week interval followed by low-dose nivolumab with adoptive immune cell therapy four times at 2-week intervals. A follow-up computed tomography scan showed partial response, with mass reduction of the metastatic lung and mediastinal lesions. Case 2 was a 77-year-old man. He received concurrent chemoradiation therapy with fluoropyrimidine/platinum, and gastroscopy revealed complete remission of esophageal cancer. He was disease free for 5 months, but routine computed tomography revealed multiple metastases in his lungs and lymph nodes. He visited our clinic to receive adoptive immune cell therapy and immune checkpoint inhibitor combination therapy. Radiographic evidence showed continuous improvement of lesions. There was no evidence of severe adverse events during the combination therapy. CONCLUSION: The combination of adoptive immune cell therapy and an immune checkpoint inhibitor might be a possible treatment strategy for advanced esophageal cancer. Trial registration UMIN000028756. Registered 14 September 2017.

[A case of rectal carcinoid with multiple liver, lymph nodes and bone metastases that responded to an octreotide therapy].

A 45-year-old man was admitted to our hospital with a chief complaint of anal bleeding. Colonoscopy revealed a lower rectal tumor diagnosed as rectal carcinoid on biopsy. Multiple metastatic liver tumors were found on abdominal CT scan. We performed an abdomino-perineal resection, a partial hepatectomy, and TACE. There seemed to be no apparent residues of a carcinoid tumor on abdominal CT. About one year after the first therapy, CT scan had revealed multiple metastases to the liver, lymph nodes and bones. Therefore, we started an octreotide LAR, which remarkably reduced the size of metastatic tumors. The treatment of an octreotide LAR had controlled the progression of metastatic tumors for two and half years. In this case, the effect of an octreotide LAR for recurrence of rectal carcinoid after local therapies brought good controls of symptoms and an inhibition of tumor growth for long-term.

Prognostic Factors for Endometrial and Cervical Cancers of Uterus Treated With Immune-cell Therapy: A Retrospective Study.

BACKGROUND/AIM: In this retrospective study, we aimed to investigate the efficacy of immune-cell therapy using T lymphocytes activated in vitro with or without dendritic cell vaccination in combination with standard therapies in terms of the survival of patients with advanced or recurrent endometrial and cervical cancers of the uterus. PATIENTS AND METHODS: A total of 187 patients with advanced or recurrent uterine cancer were enrolled in this study. The correlation between overall survival and various clinical factors was examined by univariate and multivariate analyses. RESULTS: Univariate analysis revealed that the prognosis was improved in uterine cancer patients who received immune-cell therapy without prior chemotherapy or without distant metastasis. Multivariate analysis demonstrated that the absence of prior chemotherapy for endometrial cancer and liver/lung metastasis of cervical cancer are indications for immune-cell therapy. CONCLUSION: Survival benefit in uterine cancer patients could be potentially obtained by a combination of immune-cell therapy with other therapies.

Adoptive Immune-Cell Therapy for the Treatment of Neuroendocrine Carcinoma of the Uterine Cervix.

BACKGROUND/AIM: We aimed to investigate the efficacy of immune-cell therapy in terms of the survival of patients with neuroendocrine carcinoma of the uterine cervix (NECC), which lacks standardized therapeutic approaches. PATIENTS AND METHODS: We identified 17 patients who were diagnosed as having NECC and treated with immune-cell therapy. The clinical characteristics of these patients were extracted from their records and their overall survival was measured. RESULTS: Of the 17 patients, two patients with early-stage NECC without recurrence and three patients with less than four treatments were excluded. The median survival times from the time of diagnosis and from the initial administration of immune-cell therapy were 49.7 and 24.4 months, respectively. The overall survival rates at 1, 2, and 5 years were 63.6%, 38.2%, and 25.5%, respectively. Long-term survival was observed in the patients with distant metastases. CONCLUSION: The preliminary results of this retrospective study suggested the potential efficacy of immune-cell therapy for NECC.

Effects of adaptive immune cell therapy on the immune cell profile in patients with advanced gastric cancer.

BACKGROUND: Immunotherapy for cancer patients has been the subject of attention in recent years. In this study, we investigated whether αßT-cell therapy causes changes in the host's immune cell profile, and if so, the effect of these changes on prognosis. METHODS: Peripheral blood mononuclear cells (PBMCs) from 30 gastric cancer patients who had completed one course of αßT-cell therapy were analyzed. The peripheral blood immune cell profile was established using PBMCs by counting the frequency of CD4+ helper T cells, CD8+ killer T cells, regulatory T cells (Tregs), and myeloid-derived suppressor cells and measuring the expression of their surface markers. The changes after treatment and their association with response to treatment were investigated. RESULTS: Immune cell profiles changed greatly after treatment. The frequency of CD4+ helper T cells decreased, but that of CD8+ killer T cells increased. The frequency of programmed cell death 1 (PD-1)+ effector Tregs increased significantly, but only in the non-progressive disease (non-PD) group, in which it was significantly higher compared with the PD group. Patients in whom the frequency of PD-1+ effector Tregs increased had a significantly better prognosis than those in whom it decreased. CONCLUSION: Our results suggested that αßT-cell therapy changes the host's immune cell profile, and an increase in PD-1+ effector Tregs may help improve prognosis.

Changes in Immunological Status in Patients With Metastatic Colorectal Cancer Treated With First-line Chemoimmunotherapy.

BACKGROUND/AIM: Chemoimmunotherapy is a promising treatment for various malignant diseases. In this study, we examined whether first-line chemoimmunotherapy using adoptive immune-cell therapy was effective for metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: The therapeutic efficacy and safety of the standard first-line chemoimmunotherapy with adoptive αß T cell therapy and bevacizumab were assessed using thirty-two patients with mCRC in our hospital. Immunological status after this chemoimmunotherapy was also evaluated. RESULTS: The response and disease control rates were 68.8% and 87.5%, respectively. Further, median progression-free and overall survival were 14.2 and 35.3 months. Immunotherapy-associated toxicity was minimal. Significant decrease in the change of monocyte number (p=0.006) and increase in the change of rate of lymphocyte-to-monocyte ratio (p=0.039) were seen in the complete response group. CONCLUSION: First-line chemoimmunotherapy with adoptive αß T cell therapy may be useful for mCRC.

Enhancement of anti-tumor immunity by high levels of Th1 and Th17 with a combination of dendritic cell fusion hybrids and regulatory T cell depletion in pancreatic cancer.

Regulatory T cells (Tregs) play an important role in immunological self-tolerance and protect the host from autoimmune disease. However, in cancer immunity, Tregs might block anti-tumor immune responses. Therefore, the depletion of Tregs using a specific agent that suppresses its function or population, such as an anti-CD25 antibody, could promote anti-tumor immune responses. In the present study, a cytotoxicity assay, enzyme-linked immunosorbent spot (ELISPOT) assay and measuring cytokine secretion, were used to study the efficacy of Treg depletion by anti-CD25 antibody added to a dendritic cell/tumor cell (DC/TC) fusion hybrid vaccine in a murine pancreatic cancer model. All the mice treated with the combined therapy of fusion hybrid vaccine and Treg depletion rejected tumor growth in a challenging test, although the rejection rate was 20% both for mice that received the fusion hybrids alone or Treg depletion alone. In addition, combined therapy showed a significantly improved survival in comparison to other treatment or control groups. The NK cell activity for DC/TC fusion + Treg depletion was significantly higher than that for the other treatment groups. Cytotoxic T lymphocyte (CTL) activity for DC/TC could potentially be enhanced by the addition of Treg depletion therapy. The treatments including DC/TC fusion induced IFN-gamma secreting effector cells in ELISPOT assays. Furthermore, a cytometric beads array assay used to measure cytokine secretion showed that DC/TC fusion + Treg depletion stimulated the highest levels of IFN-gamma Th1/Th2 ratios and Th17. These results demonstrate that Treg depletion combined with DC/TC fusion hybrid vaccine enhanced the efficacy of immunotherapy in pancreatic cancer by activating CTLs and NK cells.

Experimental comparison of the stapled intestinal anastomotic techniques.

Various techniques of stapled intestinal anastomoses are performed in gastroenterological surgery. Little is known about which technique is optimal. The intestines of a domestic pig were used in this study. Stapled intestinal anastomoses of three types-functional end-to-end anastomosis (FETEA), stapled side-to-end anastomosis (STEA), and stapled end-to-end anastomosis (EEA)-were constructed using pig intestines. The times for constructing anastomoses, length of the completed anastomosed intestine, strength of anastomoses, and bursting locations were measured and recorded on each group. The times required to construct FETEAs (60 S.D. 1.4 sec) were significantly less than those required for STEAs (191.5 S.D. 46.4 sec) and EEAs (274.5 S.D. 54.5 sec). The mean lengths of the completed anastomosed intestine were significantly different for FETEAs (89 S.D. 8.2 mm), STEAs (135 S.D. 6.1 mm), and EEAs (156 S.D. 6.5 mm). The bursting pressures were not significantly different among the three groups. FETEAs are superior in terms of requiring less surgical time. EEAs are superior in terms of the length of anastomosed intestines. In conclusion, anastomotic techniques should be selected properly in consideration of these features.

[Preoperative chemoradiotherapy for resectable lower rectal cancer].

To suppress local recurrence and preserve sphincter function, we performed preoperative chemoradiotherapy( CRT) of rectal cancer. Sixteen patients with lower advanced rectal cancer received tegafur/uracil/calcium folinate+RT followed by curative resection with lateral lymph node dissection 2-8 weeks later. The male/female ratio was found to be 11:5 (41-75 years old) and the CRT was feasible for all patients. There were 11-PR and 5-SD according to RECIST criteria, and lower isotope accumulation was observed for all primary tumors in FDG-PET study. After CRT, all patients received R0 curative resection (11 APR, 2 LAR, 1 Hartmann and 1 ISR). On pathological study, 3 patients showed complete response. Surgical complications including pelvic infection, delayed a wound healing and deep venous thrombosis, etc. In conclusion, preoperative CRT of advanced rectal cancer could potentially be useful for local control and sphincter saving, however, it is necessary to manage specific surgical complications due to radiation.