Predictive value of an exosomal microRNA-based signature for tumor immunity in cervical cancer patients treated with chemoradiotherapy.

Resistance of cervical cancer to radiotherapy with concurrent chemotherapy (CCRT) results in a poor prognosis. To identify new biomarkers for predicting the treatment response and prognosis, we explored exosomal microRNA (miRNA) expression signatures associated with the outcome of cervical cancer patients treated with CCRT. Exosomes were isolated from the plasma of 45 patients prior to CCRT during 2014-2020, and miRNA analysis was performed by next-generation sequencing. At a median follow-up of 38 months, 26 patients were recurrence free, 15 patients had died of the disease, and 4 patients received salvage chemotherapy due to distant metastasis. Of the 2522 miRNAs detected, 9 (miR-148a-5p, 1915-3p, 3960, 183-5p, 196b-5p, 200c-3p, 182-5p, 374a-5p, and 431-5p) showed differential expression between the recurrence-free and recurrence groups. Patients were divided into high- and low-risk groups according to the cutoff of the miRNAs-based risk score calculated from respective expression levels. The high-risk group had significantly worse disease-specific survival than the low-risk group (p < 0.001). In addition, miR-374a-5p and miR-431-5p expression showed a weak inverse correlation with tumor-infiltrating CD8+ and FOXP3+ T cells, suggesting a potential inhibitory effect on CCRT by suppressing tumor immunity. This miRNA signature could improve non-invasive monitoring and personalized treatment for cervical cancer.

Immunohistological evaluation of patients treated with intra-arterial chemoradiotherapy and surgery for oral cancer.

Preoperative intra-arterial chemoradiotherapy (IACRT) can improve the outcome and reduce the extent of surgery in patients with advanced oral cancer. However, the response to this regimen varies among patients, which may be related to the immune status of the tumor. We investigated the effects of proteins involved in tumor immunity on the outcomes of combined IACRT and surgery for oral cancer. We examined CD8 + and FoxP3 + tumor-infiltrating lymphocytes (TILs) and programmed death ligand 1 (PD-L1) expression on immune cells and tumor cells in pretreatment biopsy samples from 69 patients diagnosed with oral cancer treated with IACRT at our institution during 2000-2020. Patients with abundant CD8 + TILs had significantly better 5-year disease-specific survival (DSS) compared to that of patients with less infiltration of these cells (P = 0.016). Patients with higher FoxP3 + T-cells invasion had significantly better DSS compared to that of less FoxP3 (P = 0.005). Patients with high PD-L1 expression in tumor cells and immune cells had significantly better DSS than that of patients with low PD-L1 expression in these cells (P = 0.009 and P = 0.025, respectively). Collectively, these results suggest that the tumor immune microenvironment could affect outcomes of IACRT treatment in oral cancer.

Combined chemoradiotherapy and programmed cell death-ligand 1 blockade leads to changes in the circulating T-cell receptor repertoire of patients with non-small-cell lung cancer.

Combined chemoradiotherapy (CRT) and programmed cell death-ligand 1 (PD-L1) blockade is a new care standard for unresectable stage III non-small-cell lung cancer (NSCLC). Although this consolidation therapy has improved the overall survival of patients with NSCLC, the synergistic action mechanisms of CRT and immunotherapy on T cells remain unclear. In addition, there is a paucity of reliable biomarkers to predict clinical responses to therapy. In this study, we analyzed T-cell receptor (TCR) sequences in the peripheral blood of five patients with NSCLC. T-cell receptor analysis was undertaken before treatment, after CRT, and after PD-L1 blockade. Notably, we observed the expansion and alteration of the dominant T-cell clonotypes in all cases with a complete response. In contrast, neither expansion nor alteration of the TCR repertoire was observed in cases with progressive disease. T cell expansion was initiated after CRT and was further enhanced after PD-L1 blockade. Our findings suggest the systemic effect of CRT on circulating T cells in addition to the curative effect on limited tumor sites. Dynamic changes in circulating T-cell clonotypes could have a prognostic significance for combined CRT and PD-L1 blockade.

Prediction of treatment response from the microenvironment of tumor immunity in cervical cancer patients treated with chemoradiotherapy.

To supplement clinical decision-making in the management of cervical cancer, various prognostic factors, including tumor immune microenvironments, were examined in patients with cervical cancer treated with definitive chemoradiotherapy. We retrospectively analyzed the expression of CD8, FoxP3, HLA-1, PD-L1, and XRCC4 in 100 cases of cervical cancer. The observed tumor immune microenvironments were also classified into three types: inflamed, excluded, and cold type. Less FoxP3+ T cells and cold-type tumor were found to be poor prognostic factors in addition to non-SCC, large pre-treatment tumor volume, and three or less cycles of concurrent chemotherapy based on multivariate analysis. Cold-type tumors had significantly worse prognoses than the other two types, whereas inflamed- and excluded-type tumors showed similar 5-year disease-specific survival (P < 0.001; 0% vs. 60.3% vs. 72.3%). Radiotherapy could overcome the inhibitory immune microenvironment that occurs in excluded type. Individualized combination therapy adapted to pre-treatment tumor immunity may be necessary to improve radiotherapy outcomes in cervical cancer.

Prediction of late adverse events in pelvic cancer patients receiving definitive radiotherapy using radiation-induced gamma-H2AX foci assay.

Radiation can induce DNA double-stranded breaks, which are typically detected by the fluorescence of phosphorylated histone H2AX. In this study, we examined the usefulness of the dynamics of radiation-induced gamma-H2AX foci of peripheral blood lymphocytes (PBLs), as a marker of DNA repair ability, in predicting late adverse events from radiotherapy. A total of 46 patients with cervical, vaginal and anal canal cancers treated with radical radiotherapy between 2014 and 2019 were included in this analysis. Concurrent chemotherapy was administered in 36 cases (78.3%). Peripheral blood was obtained before treatment, and then irradiated ex vivo with 1 Gy X-ray. The ratio of radiation-induced gamma-H2AX foci in PBLs measured at 30 min and at 4 h was defined as the foci decay ratio (FDR). With a median follow-up of 54 months, 9 patients (19.6%) were observed to have late genitourinary or gastrointestinal (GU/GI) toxicity. The FDR ranged from 0.51 to 0.74 (median 0.59), with a significantly higher incidence of Grade 1 or higher late adverse events in the FDR ≥ 0.59 group. In multivariate analysis, FDR ≥ 0.59 and hypertension also emerged as significant factors associated with the development of late toxicities. Overall, our results suggest that measurement of radiation-induced gamma-H2AX foci in PBLs may predict the risk of late GU/GI toxicities from chemoradiotherapy, which can enable tailoring the radiation dose to minimize adverse effects.

Radiotherapy for HPV-related cancers: prediction of therapeutic effects based on the mechanism of tumor immunity and the application of immunoradiotherapy.

Human papillomavirus (HPV)-related cancer is one of the diseases entities for which the applications of radiotherapy have been increasing. Recently, the process of carcinogenesis from HPV infection and the mechanism of tumor immunity that develops during disease progression have been elucidated. In this review, we will describe the mechanism of tumor immunity and how chemoradiotherapy may overcome and improve the efficacy of tumor immunity. We will also discuss the usefulness of proteins involved with tumor immunity as a predictive marker of radiotherapy response, and present an overview of ongoing clinical trials of combinations of immune checkpoint inhibitors and radiotherapy to demonstrate the promising combination therapy that has been currently emerging.