Abstract:

Microchimerism， as a unique phenomenon of cellular coexistence， can be classified into fetal， maternal， and iatrogenic types. It plays a complex role in the occurrence and progression of malignant tumors. Studies indicate that microchimerism exerts bidirectional effects in tumors， functioning either as tumor-suppressive or tumor-promoting depending on factors such as cellular origin， host immune status， and tumor type. To date， the research focus is mainly on fetal microchimerism， while evidence regarding maternal and iatrogenic microchimerism remains limited， and their biological significance requires further clarification. Moreover， most existing studies rely on peripheral blood detection， with a lack of systematic investigation at the tissue level regarding lineage composition and causal mechanisms. Future studies should integrate multi-omics approaches and in vivo models to elucidate the dynamic roles of microchimerism within the tumor microenvironment and to evaluate its potential value in tumor diagnosis， prognosis， and immunotherapy.

Key words: Chimera, Neoplasms, Immunomodulation