Effects of anlotinib combined with camrelizumab and chemotherapy as first-line treatment for advanced esophageal squamous cell carcinoma on tumor immune microenvironment

Mingfang Xu; Yingda Liu; Xunjie Kuang; Xiuyong Liao; Xiaodong Zhao

doi:10.21037/jgo-2025-30

Effects of anlotinib combined with camrelizumab and chemotherapy as first-line treatment for advanced esophageal squamous cell carcinoma on tumor immune microenvironment

J Gastrointest Oncol. 2025 Aug 30;16(4):1366-1379. doi: 10.21037/jgo-2025-30. Epub 2025 Aug 16.

Authors

Mingfang Xu^{1

2}, Yingda Liu^{2

3}, Xunjie Kuang², Xiuyong Liao⁴, Xiaodong Zhao^{1

5}

Affiliations

¹ The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
² Department of Cancer Center, Daping Hospital, Army Medical University, Chongqing, China.
³ Department of Oncology, The 983rd Hospital of the Chinese People's Liberation Army Joint Logistic Support Force, Tianjin, China.
⁴ Department of Cancer Center, Qianjiang Central Hospital of Chongqing, Chongqing, China.
⁵ Department of Rheumatology & Immunology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Child Rare Diseases in Infection and Immunity, Chongqing, China.

Abstract

Background: Esophageal squamous cell carcinoma (ESCC) presents significant therapeutic challenges due to limited treatment options. While immune checkpoint inhibitors (ICIs) combined with chemotherapy have demonstrated efficacy, variable response rates underscore the necessity for enhanced therapeutic approaches. Anlotinib, a multi-target tyrosine kinase inhibitor, has shown synergistic effects with ICIs in clinical practice. However, its influence on the tumor immune microenvironment (TIME) in ESCC requires further elucidation. This study aimed to investigate anlotinib's effects on the TIME.

Methods: In our phase II trial (NCT04471480), we analyzed 8 advanced ESCC patients who achieved operability following treatment with anlotinib, camrelizumab, and chemotherapy (TCAC group). A control group (TCC group) comprised 8 patients from a separate neoadjuvant trial who received identical treatment, excluding anlotinib. Tumor-infiltrating immune cell populations (CD4⁺, CD8⁺, CD20⁺, CD68⁺, FOXP3⁺) were evaluated using multiplex immunofluorescence. Additional mechanistic insights were obtained through RNA sequencing (RNA-seq) and enzyme-linked immunosorbent assay (ELISA).

Results: Baseline immune cell profiles showed no significant intergroup differences. Post-treatment analysis revealed the TCAC group had significantly elevated CD8⁺ cell proportions and reduced FOXP3⁺ cell proportions compared to controls (P<0.05). Within the TCAC cohort, pretreatment immune cell distributions were comparable between pathological complete response (pCR) and non-pCR patients. However, post-treatment pCR patients demonstrated significantly higher CD8⁺ and lower FOXP3⁺ cell levels versus non-pCR cases (P<0.05). RNA-seq and ELISA analyses suggested anlotinib's potential to enhance the immune microenvironment through C-C motif chemokine ligand 5 (CCL5) upregulation.

Conclusions: The combination of anlotinib with camrelizumab and chemotherapy appears to modify the ESCC immune microenvironment by promoting cytotoxic CD8⁺ T cell infiltration while suppressing FOXP3⁺ regulatory T cells, possibly mediated through CCL5 induction. These results warrant further investigation of anlotinib's immunomodulatory potential in ESCC combination therapies.

Keywords: C-C motif chemokine ligand 5 (CCL5); Esophageal squamous cell carcinoma (ESCC); anlotinib; tumor immune microenvironment (TIME); tumor-infiltrating immune cells (TIICs).