Neutrophil-to-Lymphocyte Ratio and Intratumoral CD45RO-Positive T Cells as Predictive Factors for Longer Survival of Patients with Colorectal Liver Metastasis after Hepatectomy.

Colorectal cancer is the fourth most common malignancy across the world, and over 50% of patients had colorectal liver metastases (CLM). Activated neutrophils and tumor-infiltrating lymphocytes (TILs) are considered to interrupt progression of primary colorectal cancer; however, immunological host reactions to CLM have not been fully elucidated. We thus aimed to explore the prognostic implication of neutrophil-to-lymphocyte ratio (NLR) in peripheral blood and TILs in resected metastatic cancer tissues of 29 patients with CLM who underwent hepatectomy. To evaluate local immunological responses in CLM, we examined the infiltration of CD66b+ neutrophils and TILs, such as CD8+ T cells, CD45RO+ T cells, and forkhead box P3+ (FOXP3+) T cells. The presence of fewer than 4 tumors (p = 0.0005), the absence of distant metastasis (p = 0.018), adjuvant anti-cancer chemotherapy (p = 0.0013), and elevated NLR over 4.1 (p = 0.026) were found to be significant parameters related to longer survival after hepatectomy. Further, high numbers of infiltrated CD45RO+ T cells in CLM were significantly associated with longer patient survival (p = 0.020). The numbers of CD45RO+ T cells were correlated with those of CD8+ T cells (p = 0.008). The numbers of peripheral blood neutrophils were negatively correlated with those of CD45RO+ T cells (p = 0.038) and of CD66b+ neutrophils (p = 0.008) in CLM. The present data indicate that elevated peripheral blood NLR and high numbers of intratumoral CD45RO+ T cells are predictive of longer CLM patient survival after hepatectomy among current biomarkers.

High expression of olfactomedin-4 is correlated with chemoresistance and poor prognosis in pancreatic cancer.

Pancreatic cancer has an extremely poor prognosis, and identification of novel predictors of therapeutic efficacy and prognosis is urgently needed. Chemoresistance-related molecules are correlated with poor prognosis and may be effective targets for cancer treatment. Here, we aimed to identify novel molecules correlated with chemoresistance and poor prognosis in pancreatic cancer. We established 10 patient-derived xenograft (PDX) lines from patients with pancreatic cancer and performed next-generation sequencing (NGS) of tumor tissues from PDXs after treatment with standard drugs. We established a gene-transferred tumor cell line to express chemoresistance-related molecules and analyzed the chemoresistance of the established cell line against standard drugs. Finally, we performed immunohistochemical (IHC) analysis of chemoresistance-related molecules using 80 pancreatic cancer tissues. From NGS analysis, we identified olfactomedin-4 (OLFM4) as having high expression in the PDX group treated with anticancer drugs. In IHC analysis, OLFM4 expression was also high in PDXs administered anticancer drugs compared with that in untreated PDXs. Chemoresistance was observed by in vitro analysis of tumor cell lines with forced expression of OLFM4. In an assessment of tissue specimens from 80 patients with pancreatic cancer, Kaplan-Meier analysis showed that patients in the low OLFM4 expression group had a better survival rate than patients in the high OLFM4 expression group. Additionally, multivariate analysis showed that high expression of OLFM4 was an independent prognostic factor predicting poor outcomes. Overall, our study revealed that high expression of OLFM4 was involved in chemoresistance and was an independent prognostic factor in pancreatic cancer. OLFM4 may be a candidate therapeutic target in pancreatic cancer.

Frequency of CD4+CD161+ T Cell and Interleukin-10 Expression in Inflammatory Bowel Diseases.

Mucosal immune dysregulation associated with T cells plays a critical role in the development of inflammatory bowel diseases (IBD). However, the definite significances of these cells in IBD still remain unclear. Therefore, we investigated the population and expression of CD4+CD161+ T cells in the colonic lamina propria mononuclear cells (LPMCs) in patients with IBD by analyses using flow cytometry and immunohistochemistry. Interleukin-10 (IL-10) mRNA levels in both LPMCs and CD4+ T cells in lamina propria (LP-CD4+ T cells) were measured using a real-time quantitative reverse transcription-polymerase chain reaction. IL-10 production was investigated with immunohistochemistry. The results revealed that the population of CD4+CD161+ T cells was significantly decreased in active ulcerative colitis (UC) compared with inactive UC (P < 0.05). The CD4+CD161+ T cell population was inversely correlated with disease activity in patients with UC (r = -0.6326, P = 0.0055), but there was no significant correlation in those with Crohn's disease. Over-expression of IL-10 mRNA in both LPMCs and LP-CD4+ T cells were detected in active UC. Immunohistochemistry revealed decreased frequency of CD161+ cells and increased IL-10 positive cells in active UC. The frequency of CD4+CD161+ T cells and IL-10 expression was supposed to be associated with the pathological status of mucosal immunoregulation in IBD.

Predictive biomarkers for the efficacy of peptide vaccine treatment: based on the results of a phase II study on advanced pancreatic cancer.

BACKGROUND: The purpose of the present study was to explore novel biomarkers that can predict the clinical outcome of patients before treatment or during vaccination. These would be useful for the selection of appropriate patients who would be expected to exhibit better treatment outcomes from vaccination, and for facilitating the development of cancer vaccine treatments. METHODS: From a single-arm, non-randomized, human leukocyte antigen (HLA)-A-status-blind phase II trial of a vaccine treatment using three HLA-A*2402-restricted peptides for advanced pancreatic cancer (PC), we obtained peripheral blood samples from 36 patients of an HLA-A*2402-matched group and 27 patients of an HLA-A*2402-unmatched group. RESULTS: Multivariate analysis (HR = 2.546; 95% CI = 1.138 to 5.765; p = 0.0231) and log-rank test (p = 0.0036) showed that a high expression level of programmed death-1 (PD-1) on CD4+ T cells was a negative predictive biomarker of overall survival in the HLA-A*2402-matched group . Moreover, a high expression level of PD-1 on CD4+ T cells was a negative predictor for the induction of cytotoxic T lymphocytes (p = 0.0007). After treatment, we found that the upregulation of PD-1 and T cell immunoglobulin mucin-3 (Tim-3) expression on CD4+ and CD8+ T cells was significantly associated with a poor clinical outcome in the HLA-A*2402-matched group (p = 0.0330, 0.0282, 0.0046, and 0.0068, respectively). In contrast, there was no significant difference for these factors in the HLA-A*2402-unmatched group. CONCLUSIONS: Our results indicate that the upregulation of PD-1 and Tim-3 expression on CD4+ and CD8+ T cells may restrict T cell responses in advanced PC patients; therefore, combination immunotherapy with blockade of PD-1 and Tim-3 to restore T cell responses may be a potential therapeutic approach for advanced PC patients. TRIAL REGISTRATION: Clinical-Trail-Registration: UMIN000008082 .

Phase II clinical trial of peptide cocktail therapy for patients with advanced pancreatic cancer: VENUS-PC study.

We previously conducted a phase I clinical trial combining the HLA-A*2402-restricted KIF20A-derived peptide vaccine with gemcitabine for advanced pancreatic cancer (PC) and confirmed its safety and immunogenicity in cancer patients. In this study, we conducted a multicenter, single-armed, phase II trial using two antiangiogenic cancer vaccines targeting VEGFR1 and VEGFR2 in addition to the KIF20A peptide. We attempted to evaluate the clinical benefit of the cancer vaccination in combination with gemcitabine. Chemotherapy naïve PC patients were enrolled to evaluate primarily the 1-year survival rate, and secondarily overall survival (OS), progression free survival (PFS), response rate (RR), disease control rate (DCR) and the peptide-specific immune responses. All enrolled patients received therapy without the HLA-A information, and the HLA genotypes were used for classification of the patients. Between June 2012 and May 2013, a total of 68 patients were enrolled. No severe systemic adverse effects of Grade 3 or higher related to these three peptides were observed. The 1-year survival rates between the HLA-A*2402-matched and -unmatched groups were not significantly different. In the HLA-A*2402 matched group, patients showing peptide-specific CTL induction for KIF20A or VEGFR1 showed a better prognosis compared to those without such induction (P = 0.023, P = 0.009, respectively). In the HLA-A*2402-matched group, the patients who showed a strong injection site reaction had a better survival rate (P = 0.017) compared to those with a weak or no injection site reaction. This phase II study demonstrated that this therapeutic peptide cocktail might be effective in patients who demonstrate peptide-specific immune reactions although predictive biomarkers are needed for patient selection in its further clinical application.

Laparoscopic anterior pelvic exenteration for locoregionally advanced rectal cancer directly invading the urinary bladder: A case report of low anterior resection with en bloc cystectomy for sphincter preservation.

Laparoscopic multi-visceral resection in patients with T4 colorectal cancer remains controversial. A 73-year-old man was admitted to the hospital for rectosigmoid cancer directly invading the urinary bladder trigone without distant metastasis. We successfully performed complete resection by laparoscopic anterior pelvic exenteration while preserving the anus. After laparoscopic mobilization of the rectum, urinary bladder, and prostate, the urethra and urethral catheter were dissected to reveal the lower rectum. By pulling the urethral catheter toward the head, the prostate was excised retrogradely from the lower rectum anterior wall. The lower rectum was resected and anastomosed by the double stapling technique with a safe distal margin from the tumor. Pathological findings of the resected specimen indicated no residual tumor in the surgical margin. There was no evidence of recurrence 34 months after surgery. En bloc, R0, laparoscopic anterior pelvic exenteration for T4 rectal cancer is feasible. However, further studies with long-term follow-up are required to resolve oncological outcomes.

Clinicopathological features, postoperative survival and prognostic variables for cancer-related survival in patients with mucinous colorectal carcinoma.

PURPOSE: To investigate the clinicopathological features and postoperative survival of patients with mucinous colorectal carcinoma (MC) and to identify the factors related to long-term survival. METHODS: Twenty-three patients who had undergone resection for MC at Miyazaki University Hospital from 1991 to 2006 were followed up for at least 5 years or until death. The effects of the clinicopathological variables on the 5-year cancer-specific survival were assessed by the univariate analyses. These patients' clinicopathological data were compared with those of 403 non-mucinous carcinoma (NMC) patients (102 well-differentiated adenocarcinomas, 301 moderately differentiated adenocarcinomas). RESULTS: The 5-year cancer-specific survival rate was significantly worse in MC (56.2 %) than in NMC (73.8 %; p = 0.008) cases. Univariate analyses showed the T factor, lymph node metastases, liver metastases, metastases to the distant peritoneum, remote metastases and curative resection to be significant factors predicting the survival. However, there were no significant differences in the postoperative survival in patients with stage II-IV disease. The rates of metastases to the distant peritoneum, M1, T4, a tumor size ≥5 cm and non-curative resection were higher in MC than in NMC patients. CONCLUSIONS: Patients with MC had advanced stage cancer, especially with metastases to the distant peritoneum, more frequently than did the patients with NMC. To improve the survival of these patients, it is therefore important to detect MC at an early stage and to perform curative resection.

Recombinant modified vaccinia virus ankara (MVA) expressing wild-type human p53 induces specific antitumor CTL expansion.

The p53 gene product is an attractive target for tumor immunotherapy. The present study aims to understand the potential of MVAp53 vaccine to induce expansion of p53-specific cytotoxic T lymphocyte ex vivo in cancer patients. The result indicated that 14 of 23 cancer patients demonstrated p53-specific IFN-γ production, degranulation, cell proliferation, and lysis of p53 overexpressed human tumor cell lines. These experiments show that MVAp53 stimulation has the potential to induce the expansion of p53-specific cytotoxic T lymphocyte from the memory T cell repertoire. The data suggest that MVAp53 vaccine is an ideal candidate for cancer immunotherapy.

Enhancement of cancer vaccine therapy by systemic delivery of a tumor-targeting Salmonella-based STAT3 shRNA suppresses the growth of established melanoma tumors.

Cancer vaccine therapies have only achieved limited success when focusing on effector immunity with the goal of eliciting robust tumor-specific T-cell responses. More recently, there is an emerging understanding that effective immunity can only be achieved by coordinate disruption of tumor-derived immunosuppression. Toward that goal, we have developed a potent Salmonella-based vaccine expressing codon-optimized survivin (CO-SVN), referred to as 3342Max. When used alone as a therapeutic vaccine, 3342Max can attenuate growth of aggressive murine melanomas overexpressing SVN. However, under more immunosuppressive conditions, such as those associated with larger tumor volumes, we found that the vaccine was ineffective. Vaccine efficacy could be rescued if tumor-bearing mice were treated initially with Salmonella encoding a short hairpin RNA (shRNA) targeting the tolerogenic molecule STAT3 (YS1646-shSTAT3). In vaccinated mice, silencing STAT3 increased the proliferation and granzyme B levels of intratumoral CD4(+) and CD8(+) T cells. The combined strategy also increased apoptosis in tumors of treated mice, enhancing tumor-specific killing of tumor targets. Interestingly, mice treated with YS1646-shSTAT3 or 3342Max alone were similarly unsuccessful in rejecting established tumors, whereas the combined regimen was highly potent. Our findings establish that a combined strategy of silencing immunosuppressive molecules followed by vaccination can act synergistically to attenuate tumor growth, and they offer a novel translational direction to improve tumor immunotherapy.

Modified vaccinia Ankara expressing survivin combined with gemcitabine generates specific antitumor effects in a murine pancreatic carcinoma model.

Survivin is overexpressed by 70-80% of pancreatic cancers, and is associated with resistance to chemotherapy and a poor prognosis. Gemcitabine has been a standard treatment for patients with advanced pancreatic cancer for a decade. Recent reports have demonstrated that gemcitabine treatment attenuates the tumor-suppressive environment by eliminating CD11b(+)/Gr-1(+) myeloid-derived suppressor cells (MDSCs). We hypothesize that a cancer vaccine targeting survivin can achieve enhanced efficacy when combined with gemcitabine. In this study, we tested this hypothesis using modified vaccinia Ankara (MVA) expressing full-length murine survivin. The poorly immunogenic mouse pancreas adenocarcinoma cell line, Pan02, which expresses murine survivin and is syngeneic to C57BL/6, was used for this study. Immunization with MVA-survivin resulted in a modest therapeutic antitumor effect on established Pan02 tumors. When administered with gemcitabine, MVA-survivin immunization resulted in significant tumor regression and prolonged survival. The enhanced vaccine efficacy was associated with decreased CD11b(+)/Gr-1(+) MDSCs. To analyze the survivin-specific immune response to MVA-survivin immunization, we utilized a peptide library of 15mers with 11 residues overlapping from full-length murine survivin. Splenocytes from mice immunized with MVA-survivin produced intracellular γ-interferon in response to in vitro stimulation with the overlapping peptide library. Increased survivin-specific CD8(+) T cells that specifically recognized the Pan02 tumor line were seen in mice treated with MVA-survivin and gemcitabine. These data suggest that vaccination with MVA-survivin in combination with gemcitabine represents an attractive strategy to overcome tumor-induced peripheral immune tolerance, and this effect has potential for clinical benefit in pancreatic cancer.

Heterologous prime/boost immunization with p53-based vaccines combined with toll-like receptor stimulation enhances tumor regression.

The p53 gene product is overexpressed in approximately 50% of cancers, making it an ideal target for cancer immunotherapy. We previously demonstrated that a modified vaccinia Ankara (MVA) vaccine expressing human p53 (MVA-p53) was moderately active when given as a homologous prime/boost in a human p53 knock in (Hupki) mouse model. We needed to improve upon the inefficient homologous boosting approach, because development of neutralizing immunity to the vaccine viral vector backbone suppresses its immunogenicity. To enhance specificity, we examined the combination of 2 different vaccine vectors provided in sequence as a heterologous prime/boost. Hupki mice were evaluated as a human p53 tolerant model to explore the capacity of heterologous p53 immunization to reject human p53-expressing tumors. We employed attenuated recombinant Listeria monocytogenes expressing human p53 (LmddA-LLO-p53) in addition to MVA-p53. Heterologous p53 immunization resulted in a significant increase in p53-specific CD8 and CD4 T cells compared with homologous single vector p53 immunization. Heterologous p53 immunization induced protection against tumor growth but had only a modest effect on established tumors. To enhance the immune response we used synthetic double-strand RNA (polyinsosinic:polycytidylic acid) and unmethylated CpG-containing oligodeoxynucleotide to activate the innate immune system via Toll-like receptors. Treatment of established tumor-bearing Hupki mice with polyinsosinic:polycytidylic acid and CpG-oligodeoxynucleotide in combination with heterologous p53 immunization resulted in enhanced tumor rejection relative to treatment with either agent alone. These results suggest that heterologous prime/boost immunization and Toll-like receptor stimulation increases the efficacy of a cancer vaccine, targeting a tolerized tumor antigen.

Suppression of choroidal neovascularization by vaccination with epitope peptide derived from human VEGF receptor 2 in an animal model.

PURPOSE: It has been shown that vaccination with peptides derived from human vascular endothelial growth factor receptor 2 (VEGFR2) induces cytotoxic T lymphocytes (CTLs) with potent cytotoxicity against endothelial cells expressing VEGFR2 in a A2/Kb transgenic mice system expressing human HLA-A*0201. The present study examined the efficacy of this immunotherapy against age-related macular degeneration (AMD) using a choroidal neovascularization (CNV) model. METHODS: Seven- to 10-week-old A2/Kb transgenic mice expressing human HLA-A*0201 were used. The mice were divided into three groups of 15 animals each: phosphate-buffered saline (PBS) treatment (control); immunity adjuvant (incomplete Freund adjuvant [IFA]); and antigen peptide of human VEGFR 2 and IFA (peptide vaccination group). Immunization was given on days 0 and 11. On day 20, six CNVs were induced in both eyes of each animal using a semiconductor laser set to 75 mum, 200 mW, and 0.05 seconds. Leakage from the CNV was measured by fluorescein angiography 7 days after laser treatment. CNV volume was measured using a choroidal flatmount after perfusing the mice with fluorescein conjugate lectin. RESULTS: There were no significant differences in the leakage or the area of CNV in the IFA-treated group compared with controls. In contrast, the fluorescent leakage index in the peptide vaccination group was reduced to 80% and the CNV area to 18% compared with the control group (P < 0.0001 and P < 0.05, respectively). CONCLUSIONS: This model provides a rationale for immunotherapy using the epitope peptides derived from VEGFR2 for the treatment of CNV.

Inhibition of tumor growth with antiangiogenic cancer vaccine using epitope peptides derived from human vascular endothelial growth factor receptor 1.

PURPOSE: Antiangiogenic therapy is now considered to be one of promising approaches to treat various types of cancer. In this study, we examined the possibility of developing antiangiogenic cancer vaccine targeting vascular endothelial growth factor receptor 1 (VEGFR1) overexpressed on endothelial cells of newly formed vessels in the tumor. EXPERIMENTAL DESIGN: Epitope-candidate peptides were predicted from the amino acid sequence of VEGFR1 based on their theoretical binding affinities to the corresponding HLAs. The A2/Kb transgenic mice, which express the alpha1 and alpha2 domains of human HLA-A*0201, were immunized with the epitope candidates to examine their effects. We also examined whether these peptides could induce human CTLs specific to the target cells in vitro. RESULTS: The CTL responses in A2/Kb transgenic mice were induced with vaccination using identified epitope peptides restricted to HLA-A*0201. Peptide-specific CTL clones were also induced in vitro with these identified epitope peptides from peripheral blood mononuclear cells donated by healthy volunteers with HLA-A*0201. We established CTL clones in vitro from human peripheral blood mononuclear cells with HLA-A*2402 as well. These CTL clones were shown to have potent cytotoxicities in a HLA class I-restricted manner not only against peptide-pulsed target cells but also against target cells endogenously expressing VEGFR1. Furthermore, immunization of A2/Kb transgenic mice with identified epitope peptides restricted to HLA-A*0201 was associated with significant suppression of tumor-induced angiogenesis and tumor growth without showing apparent adverse effects. CONCLUSIONS: These results strongly suggest that VEGFR1 is a promising target for antiangiogenic cancer vaccine and warrants further clinical development of this strategy.