Comparison of dynamic changes in the peripheral CD8+ T cells function and differentiation in ESCC patients treated with radiotherapy combined with anti-PD-1 antibody or concurrent chemoradiotherapy

Changes in PD-1 expression on T lymphocyte subsets and related immune indicators before and after definitive chemoradiotherapy for esophageal squamous cell carcinoma

OBJECTIVE

This study aimed to observe the dynamic changes in the expression of T lymphocytes, natural killer (NK) cells, and PD-1 in patients with first-diagnosed esophageal squamous cell carcinoma (ESCC) before and after chemoradiotherapy (CRT) and evaluate the impact of PD-1 expression in peripheral blood on the short-term outcome of patients with ESCC.

PATIENTS AND METHODS

Seventy-three patients with ESCC who were treated with definitive CRT were enrolled. Before and after CRT, flow cytometry was used to detect thePD-1 expression in the peripheral blood and related immune indicators. Peripheral blood from 10 healthy individuals was used as control.

RESULTS

The percentages of CD3+ (p = 0.018), CD4+ (p < 0.001), and CD8+ T cells (p < 0.001); NK cells (p = 0.009); and the CD4+/CD8+ ratio (p < 0.001), as well as PD-1+CD3+ (p < 0.001), PD-1+CD4+ (p < 0.001), and PD-1+CD8+ (p < 0.001) T cells, before CRT significantly differed from those in the post-CRT group. The percentages of PD-1+CD8+ T cells differed significantly between the radiotherapy alone and CRT groups (p < 0.05). PD-1 expression in CD3+, CD4+, and CD8+ T cells significantly decreased in patients achieving overall response rate (all p < 0.05). Compared with those in the incomplete response group, PD-1+CD8+ T cells significantly decreased in the CR group (p < 0.05).

CONCLUSION

CRT aggravated immunosuppression and increased PD-1 expression in T lymphocyte subsets in patients with ESCC, possibly related to the radiation field. PD-1 expression in T lymphocyte subsets can predict short-term outcomes in patients and provide a theoretical basis for the sequential application of PD-1 immunosuppressants after radiotherapy and chemotherapy.

Radiotherapy modulates autophagy to reshape the tumor immune microenvironment to enhance anti-tumor immunity in esophageal cancer

The combination of radiotherapy and immunotherapy exerts synergistic antitumor in a range of human cancers, and also in esophageal cancer. Radiotherapy-induced tumor immune microenvironment (TIME) reprogramming is an essential basis for the synergistic antitumor between radiotherapy and immunotherapy. Radiotherapy can induce autophagy in tumor cells and immune cells of TIME, and autophagy activation is involved in the modification of immunological characteristics of TIME. The TIME landscape of esophageal cancer, especially ESCC, can be affected by radiotherapy or autophagy regulation. In this review, we depicted that local radiotherapy-induced autophagy could promote the maturation, migration, infiltration, and function of immune cells by complicated mechanisms to make TIME from immune "cold" to "hot", resulting in the synergistic antitumor of RT and IO. We argue that unraveling the relevance of radiotherapy-initiated autophagy to driving radiotherapy reprogramming TIME will open new ideas to explore new targets or more efficiently multimodal therapeutic interventions in ESCC.

Factors affecting prognosis in patients with locally advanced and advanced esophageal cancer receiving definitive radiotherapy in plateau regions

Esophageal cancer is one of the most prevalent malignancies. This study aimed to examine the impact of factors such as immunotherapy, altitude, radiotherapy target volume, and radiotherapy dose on the prognosis of patients with locally advanced and advanced esophageal cancer who are receiving definitive radiotherapy and living in high-altitude regions. We retrospectively collected data from all patients with locally advanced and advanced esophageal cancer who completed definitive radiotherapy at Yunnan Cancer Hospital between January 2017 and January 2023. A total of 274 patients were included, with a median follow-up time of 24.5 months. The median overall survival (OS) and progression-free survival (PFS) were 15.0 months and 11.0 months, respectively. Adjuvant therapy (including chemotherapy, immunotherapy, and antiangiogenic targeted therapy, P = 0.004) and gross target volume (GTV, P = 0.015) were independent predictors of overall survival, whereas body mass index (BMI, P = 0.037) was an independent predictor of progression-free survival. Patients with a smaller planning target volume (PTV), clinical target volume (CTV), GTV, and gross tumor volume of metastatic regional lymph nodes (GTVnd), as well as those with a smaller New target volume, had a better prognosis. Treatment efficacy affects patient prognosis, with those showing early therapeutic effectiveness having a better prognosis than those for whom the treatment is ineffective. Patients who experienced disease progression within three months after the end of radiotherapy had a poorer prognosis. The altitude and radiotherapy dose had no significant impact on the prognosis of esophageal cancer patients. The location of the lesion, GTV, and simultaneous integrated boost (SIB) radiotherapy were factors influencing the occurrence of esophageal fistulas.

Neoadjuvant immunotherapy for DNA mismatch repair proficient/microsatellite stable non-metastatic rectal cancer: a systematic review and meta-analysis

Background

Neoadjuvant immunotherapy (NIT) has been endorsed by clinical guidelines for the management of DNA mismatch repair deficiency/microsatellite instability-high (dMMR/MSI-H) locally advanced rectal cancer (LARC). Nonetheless, the therapeutic efficacy of NIT in mismatch repair-proficient/microsatellite stable (pMMR/MSS) non-metastatic rectal cancer (RC) remain pending matters. Therefore, a meta-analysis was carried out to assess the efficacy and safety of NIT in patients with non-metastatic pMMR/MSS RC.

Methods

PubMed, Embase, Web of Science, the Cochrane Library, ClinicalTrials.gov, ASCO and ESMO were searched to obtain related studies up to July 2024. Two reviewers independently screened the included articles and extracted the pertinent data. The risk of publication bias was assessed by Begg or Egger tests and in cases of publication bias, the trim and fill method was applied. Heterogeneity was assessed using I 2 statistics.

Results

Thirteen articles including 582 eligible patients were analyzed. The pooled pCR, MPR, cCR and anus preservation rate were 37%, 57%, 26% and 77% separately and the incidence of irAEs≥3 grades and TRAEs≥3 grades were 3% and 29%, respectively. Non-metastatic pMMR/MSS RC receiving the short-course radiotherapy (SCRT) in neoadjuvant setting exhibited superior pooled pCR and MPR than long-course radiotherapy (LCRT) without upregulating the incidence of adverse effects. Furthermore, patients with MSS RC underwent neoadjuvant treatment with anti-PD-1 inhibitors demonstrated higher pooled pCR, MPR, cCR compared to those receiving PD-L1 inhibitors. Additionally, yielded improved pooled MPR and anal preservation rates compared to sequential immuno-radiotherapy (63.4% vs 51.2% and 88.5% vs 69.9%), without raising the incidence of irAEs≥3 grade. Interestingly, RC patients with lymph node metastasis showed a higher pooled pCR than those without lymph node metastasis (43% vs 35%).

Conclusion

NIT was linked to favorable response rates and anal preservation, alongside an acceptable safety profile. Non-metastatic pMMR/MSS RC patients receiving SCRT, PD-1 inhibitors, or concurrent immuno-radiotherapy in the neoadjuvant setting exhibited enhanced outcomes. This meta-analysis provides evidence for further exploration and application of NIT in non-metastatic pMMR/MSS RC and highlights the potential for organ preservation with this approach. The relatively small sample size and the uneven quality of included studies may have had some impact on the generality of the results. Therefore, further analysis with a higher number of high-quality studies is needed to verify the conclusions.

Systematic review registration

https://inplasy.com/, identifier: INPLASY202470110.

Mediating role of circulating inflammatory proteins in the effect of immune cells on esophageal cancer risk: A Mendelian randomization study

The immune system and inflammatory processes play crucial roles in the development of esophageal cancer (EC). This study aimed to investigate the causal relationships between 731 immune cell phenotypes, 91 circulating inflammatory proteins, and EC, with a particular focus on the mediating role of circulating inflammatory proteins. Utilizing public genetic data, we applied a 2-sample Mendelian Randomization (MR) method to examine the causal relationships between 731 immune cell phenotypes, 91 circulating inflammatory proteins, and EC. Comprehensive sensitivity analyses were conducted to assess the robustness, heterogeneity, and horizontal pleiotropy of the MR results. Additionally, a 2-step MR method was employed to quantify the impact and proportion of immune cell phenotypes mediated by circulating inflammatory proteins on EC. Eleven immune cell phenotypes and 1 inflammatory cytokine were found to have causal relationships with EC, with results stable across all sensitivity analyses. Mediation analyses revealed that only 2 cell phenotypes had causal relationships with EC through interleukin-10: CD3 on human leukocyte antigen-DR (HLA-DR)+ T cells (mediation effect = -0.009; mediation proportion = 12.01%) and monocytic myeloid-derived suppressor cell absolute count (mediation effect = 0.018; mediation proportion = 18.97%). This study enhances the understanding of the causal relationships between immune cells, circulating inflammatory proteins, and EC. The findings highlight the potential mediating role of interleukin-10, providing new insights into the mechanisms by which immune cells may influence esophageal tumorigenesis.

Association of immune cells and the risk of esophageal cancer: A Mendelian randomization study in a East Asian population

Immunotherapy has been used in esophageal cancer (EC), but the causal relationship between EC and immune cells is not clear. Although the cellular phenotype has been reported as a biomarker for immunotherapy, the biomarker studies for immunotherapy in EC still face great challenges. Comprehensive 2-sample Mendelian randomization (MR) analysis was performed to determine the causal association between immune cell signatures and EC in this study. Based on publicly available genetic data, we explored causal associations between 731 immune cell signatures and EC risk. EC had no statistically significant effect on immunophenotypes. Nine immunophenotype types were positively associated with the risk of EC: CD20-%B cell, CD20% lymphocytes, CD25 on IgD- CD27-, CD25 on IgD+ CD24+, CD27 on IgD+ CD24+, CD28+ CD45RA- CD8br AC, CD3 on TD CD8br, IgD-CD38dim%B cells, and Mo MDSC AC. In addition, a total of 15 immunophenotypes were identified as causally associated with EC. IgD+ CD38- %B cell, IgD- CD24- %lymphocyte, CD19 on IgD- CD38dim, CD20 on IgD+ CD24+, CD62L-myeloid DC AC, CD4+ AC, Lymphocyte %leukocyte, CD3 on HLA-DR+ T cell, CD3 on CD45RA- CD4+, HVEM on naive CD4+ AC, HVEM on CD45RA- CD4+, CD4 on TD CD4+, CD4 on CD4 Treg, and CD4 on CD39+ resting Treg, and CD4 on activated & secreting Treg. Our study has demonstrated the close connection between immune cells and EC by genetic means, thus providing guidance for future clinical research.

Mechanisms of radiotherapy resistance and radiosensitization strategies for esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is the sixth most common cause of cancer-related mortality worldwide, with more than half of them occurred in China. Radiotherapy (RT) has been widely used for treating ESCC. However, radiation-induced DNA damage response (DDR) can promote the release of cytokines and chemokines, and triggers inflammatory reactions and changes in the tumor microenvironment (TME), thereby inhibiting the immune function and causing the invasion and metastasis of ESCC. Radioresistance is the major cause of disease progression and mortality in cancer, and it is associated with heterogeneity. Therefore, a better understanding of the radioresistance mechanisms may generate more reversal strategies to improve the cure rates and survival periods of ESCC patients. We mainly summarized the possible mechanisms of radioresistance in order to reveal new targets for ESCC therapy. Then we summarized and compared the current strategies to reverse radioresistance.