Various vaccine treatments against metastatic colorectal cancer have been developed and applied. However, to improve the efficacy of immunotherapy, biomarkers that can predict the effects are needed. ...It has been reported that various microRNAs (miRNAs) in peripheral blood may be useful as non-invasive biomarkers. In this study, miRNAs influencing the efficacy of vaccine treatment were screened for in a microarray analysis of 13 plasma samples that were obtained from patients prior to vaccine treatment. To validate the screening results, real-time RT-PCR was performed using 93 plasma samples obtained from patients prior to vaccine treatment. Four candidate miRNAs were selected according to the results of the comprehensive analysis of miRNA expression, which were ranked using the Fisher criterion and the absolute value of the log2 ratio in the screening analysis. The validation analysis showed that in the HLA-A*2402-matched patient group (vaccine-treated group), patients with a high expression of plasma miR-6826 had a poorer prognosis than those with a low expression (P=0.048). In contrast, in the HLA-A*2402-unmatched patient group (control group), there was no difference between the patients with high or low plasma miR-6826 expression (P=0.168). Similar results were obtained in the analysis of miR-6875 (P=0.029 and P=0.754, respectively). Moreover, multivariate analysis of the Cox regression model indicated that the expression of miR-6826 was the most significant predictor for overall survival (P=0.003, hazard ratio, 3.670). In conclusion, plasma miR-6826 and miR-6875 may be predictive biomarkers for a poor response to vaccine treatment. Although further clarification is needed regarding the functions of miR-6826 and miR-6875 and their relationship to immune-related molecules, plasma miR-6826 and miR-6875 may be useful negative biomarkers for predicting the efficacy of vaccine treatment.
The cancer stroma is important in cancer development, however, whether the aberrant expression of microRNAs (miRNAs) in the cancer stroma is associated with cancer progression remains to be fully ...elucidated. The aim of the present study was to identify the miRNAs associated with liver metastasis in the cancer stroma of human colorectal cancer (CRC). Using laser capture microdissection, cancer stroma was obtained from the primary lesion of six patients with CRC with liver metastasis (CRCwLM) and six patients with CRC without liver metastasis (CRCwoLM), and miRNA microarray analysis was performed. Candidate miRNA expression status in the stroma was validated by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis in 40 CRC cases (wLM, n=20; woLM, n=20), and the association between miRNA expression and clinicopathological factors was assessed in 101 advanced CRC samples. The localization of candidate miRNAs in CRCs was analyzed using in situ hybridization analysis (ISH). The microarray analysis identified six miRNAs with expression differing between the CRCwLM and CRCwoLM cancer stroma. Validation using RT‑qPCR analysis of the stroma showed that the expression levels of miR‑221 and miR‑222 in the cancer stroma were significantly higher in CRCwLM than in CRCwoLM. The RT‑qPCR analysis of 101 CRC samples showed that a high expression level of miR‑221 or miR‑222 in the cancer stroma was associated with liver metastasis, distant metastasis, and shorter overall survival rate of patients with CRC (P<0.05). Increased levels of miR‑221 and miR‑222 were observed in cancer cells and in fibroblasts in the stromal tissue in the ISH analysis. The results suggested that the overexpression of miR‑221 and miR‑222 in the cancer stroma is associated with the metastatic activity and malignant potential in patients with CRC.
We previously conducted a phase I trial for advanced colorectal cancer (CRC) using five HLA-A*2402-restricted peptides, three derived from oncoantigens and two from vascular endothelial growth factor ...(VEGF) receptors, and confirmed safety and immunological responses. To evaluate clinical benefits of cancer vaccination treatment, we conducted a phase II trial using the same peptides in combination with oxaliplatin-based chemotherapy as a first-line therapy.
The primary objective of the study was the response rates (RR). Progression free survival (PFS), overall survival (OS), and immunological parameters were evaluated as secondary objective. The planned sample size was more than 40 patients for both HLA2402-matched and -unmatched groups. All patients received a cocktail of five peptides (3 mg each) mixed with 1.5 ml of IFA which was subcutaneously administered weekly for the first 12 weeks followed by biweekly administration. Presence or absence of the HLA-A*2402 genotype were used for classification of patients into two groups.
Between February 2009 and November 2012, ninety-six chemotherapy naïve CRC patients were enrolled under the masking of their HLA-A status. Ninety-three patients received mFOLFOX6 and three received XELOX. Bevacizumab was added in five patients. RR was 62.0% and 60.9% in the HLA-A*2402-matched and -unmatched groups, respectively (p=0.910). The median OS was 20.7 months in the HLA-A*2402-matched group and 24.0 months in the unmatched group (log-rank, p=0.489). In subgroup with a neutrophil/lymphocyte ratio (NLR) of <3.0, patients in the HLA-matched group did not survive significantly longer than those in the unmatched group (log-rank, p=0.289) but showed a delayed response.
Although no significance was observed for planned statistical efficacy endpoints, a delayed response was observed in subgroup with a NLR of <3.0. Biomarkers such as NLR might be useful for selecting patients with a better treatment outcome by the vaccination.
Trial registration: UMIN000001791.
The aim of the present study was to characterize infiltrated T cell clones that define the tumor immune environment and are important in the response to treatment in patients with advanced colorectal ...cancer (CRC). In order to explore predictive biomarkers for the efficacy of immunochemotherapies, T cell receptor (TCR) repertoire analysis was performed using blood samples and tumor tissues obtained from patients with advanced CRC that had been treated with a combination of five-cancer peptide vaccines and oxaliplatin-based chemotherapy. The TCR-α/β complementary DNAs (cDNAs), prepared from the messenger RNAs (mRNAs) obtained from 17 tumor tissues and 39 peripheral blood mononuclear cells of 9 CRC patients at various time points, were sequenced. The oligoclonal enrichment of certain TCR sequences was identified in tumor tissues and blood samples; however, only a few TCR sequences with a frequency of >0.1% were commonly detected in pre- and post-treatment tumor tissues, or in post-treatment blood and tissue samples. The average correlation coefficients of the TCR-α and TCR-β clonotype frequencies between the post-treatment tumor tissues and blood samples were 0.023 and 0.035, respectively, and were much lower compared with the correlation coefficients of the TCR-α and TCR-β clonotype frequencies between pre- and post-treatment blood samples (0.430 and 0.370, respectively), suggesting that T cell populations in tumor tissues vary from those in blood. Although the sample size was small, a tendency for the TCR diversity in tumor tissues to drastically decrease during the treatment was indicated in two patients, who exhibited a longer progression-free survival time. The results of the present study suggest that TCR diversity scores in tissues may be a useful predictive biomarker for the therapeutic effect of immunochemotherapy for patients with advanced CRC.
Cancer vaccines have been developed as a new therapeutic approach, however, their clinical benefit remains limited. We previously performed a phase II study for advanced colorectal cancer (CRC) using ...five human leukocyte antigen (HLA-A*24:02)-restricted peptides derived from kinase of the outer chloroplast membrane 1, translocase of outer mitochondrial membrane 34 (TOMM34), ring finger protein 43 (RNF43), vascular endothelial growth factor receptor 1 (VEGFR1) and VEGFR2. In the present study the relationship between overall survival (OS) and several biomarkers, including cytotoxic T lymphocyte (CTL) and immunoglobulin G (IgG) responses to these five peptides, was investigated. In 89 advanced CRC patients treated with a combination therapy consisting of these five peptides and oxaliplatin-based chemotherapy, plasma was collected before and after 3 months of vaccine administration. IgGs reactive to each of the five peptides were assessed using the multiplex bead suspension Luminex system. Antigen-specific T-cell responses were estimated by enzyme-linked immunoSpot assay. Plasma levels of TOMM34 IgG (P<0.001), RNF43 IgG (P<0.001) and VEGFR2 IgG (P<0.001) were significantly increased after vaccination and stronger VEGFR2 IgG responses correlated significantly with OS in HLA-matched patients (P=0.034). CTL responses to VEGFR1 and VEGFR2 were also significantly increased in the HLA-matched group (P=0.049 and P<0.001, respectively). However, increased CTL response did not correlate with OS. Multivariate analysis indicated that IgG responses to VEGFR2 were the most significant predictor for OS in the HLA-A*24:02-matched group (P=0.04). Our findings indicated that VEGFR2 IgG responses may be an important immunological biomarker in the early course of treatment for CRC patients treated with therapeutic epitope peptides.
We previously reported a phase I study of a cancer vaccine using five novel HLA-A*2402-restricted peptides, and demonstrated the safety and the promising potential of our five-peptide cocktail for ...advanced colorectal cancer. The objective of this analysis was to investigate predictive biomarkers for the prior selection of patients who are likely to have clinical benefit from such therapy.
Seventeen patients with colorectal cancer who were treated with the five peptides underwent a complete blood count, serum chemistry tests and enzyme-linked ImmunoSpot assay before the treatment as predictive markers of high reactivity to the peptides.
Interleukin-6 level was a significant predictor for overall survival of patients treated with the peptide cocktail (p=0.017). A high neutrophil/lymphocyte ratio was likely to have some association with the poor induction of peptide-specific immune reaction.
Interleukin-6 level might be a good predictive biomarker for clinical benefit of patients treated with this peptide vaccine.
Doc number: 108 Abstract Background: We previously conducted a phase I trial for advanced colorectal cancer (CRC) using five HLA-A*2402-restricted peptides, three derived from oncoantigens and two ...from vascular endothelial growth factor (VEGF) receptors, and confirmed safety and immunological responses. To evaluate clinical benefits of cancer vaccination treatment, we conducted a phase II trial using the same peptides in combination with oxaliplatin-based chemotherapy as a first-line therapy. Methods: The primary objective of the study was the response rates (RR). Progression free survival (PFS), overall survival (OS), and immunological parameters were evaluated as secondary objective. The planned sample size was more than 40 patients for both HLA2402-matched and -unmatched groups. All patients received a cocktail of five peptides (3 mg each) mixed with 1.5 ml of IFA which was subcutaneously administered weekly for the first 12 weeks followed by biweekly administration. Presence or absence of the HLA-A*2402 genotype were used for classification of patients into two groups. Results: Between February 2009 and November 2012, ninety-six chemotherapy naïve CRC patients were enrolled under the masking of their HLA-A status. Ninety-three patients received mFOLFOX6 and three received XELOX. Bevacizumab was added in five patients. RR was 62.0% and 60.9% in the HLA-A*2402-matched and -unmatched groups, respectively (p = 0.910). The median OS was 20.7 months in the HLA-A*2402-matched group and 24.0 months in the unmatched group (log-rank, p = 0.489). In subgroup with a neutrophil/lymphocyte ratio (NLR) of < 3.0, patients in the HLA-matched group did not survive significantly longer than those in the unmatched group (log-rank, p = 0.289) but showed a delayed response. Conclusions: Although no significance was observed for planned statistical efficacy endpoints, a delayed response was observed in subgroup with a NLR of < 3.0. Biomarkers such as NLR might be useful for selecting patients with a better treatment outcome by the vaccination. Trial registration: Trial registration: UMIN000001791.
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