CELL INTELLIGENCE · 肿瘤细胞治疗研究

Clinicopathological features and the status of microenvironment fibrosis (MF) around tumor masses were evaluated in 20 MCC patient and tissue sections. Alpha-smooth muscle actin ( -SMA)-positive CAFs ( -SMA + CAFs), interleukin-6-positive CAFs (IL6 + CAFs), CD4-positive TILs (CD4 + TILs), and CD8-positive TILs (CD8 + TILs) in MCC tissue samples were investigated using immunohistochemistry.

In a total of 20 MCC patients, high-MF was detected in 12 (60%) patients which was significantly associated with worse progression-free survival (p=0.048), but not with overall survival. CD4 + /CD8 + TILs were frequently detected in MCC tissues. High-intra-tumoral CD8 + TIL was significantly associated with better overall and progression-free survival (p=0.04 and p=0.015) in our cohort. High- SMA + CAFs were detected in 11 (55.0%) patients and high-IL6 + CAFs in 10 (50.0%) patients. A negative association was found between high-IL6 + CAF and high-intra-tumoral CD8 + TILs (p=0.005). Patients with high IL6 + CAFs showed worse overall/progression-free survival than patients with low-IL6 + CAFs (p=0.022 and p=0.035).

IL6 + CAFs may largely influence the tumor immune microenvironment of MCC by modulating distinct T-cell populations and functions. This study provides a possible therapeutic target to overcome resistance to immune therapies in MCC.