Guizhi-Fuling Wan suppresses carcinoma-associated mesenchymal stem cells-induced ovarian cancer progression via STAT3 inhibition.
Ovarian cancer (OC) is the most lethal gynecological malignancy. While carcinoma-associated mesenchymal stem cells (CA-MSCs) in tumor microenvironment are known to facilitate OC progression, the underlying mechanisms remain incompletely understood. The classical herbal formula Guizhi-Fuling Wan (GZFL) has demonstrated significant clinical efficacy in OC maintenance therapy, however, its therapeutic mechanisms require further exploration for precision clinical applications. Immunohistochemical analysis of 45 ovarian tumor specimens revealed the clinical significance of p-STAT3 expression and CA-MSCs filtration patterns. Mechanistic studies employed STAT3 knockout (KO) cell lines. To evaluate the tumor-promoting effects of CA-MSCs and the therapeutic potential of GZFL, cancer cells were co-cultured with CA-MSCs and assessed using anti-proliferation, 3D spheroid formation, transwell invasion assays, and in vivo xenograft models. EMT-related protein expression was assessed in co-culture systems to further validate the biological activity of GZFL. Clinically, STAT3 activation strongly correlated with CA-MSCs infiltration as well as with OC progression. We found that CA-MSCs promote OC proliferation and metastasis through a mechanism mediated by STAT3, as STAT3 KO cells showed markedly reduced responsiveness. GZFL effectively blocked CA-MSCs-induced proliferation and metastasis both in vitro and in mice. Further molecular analyses revealed that GZFL disrupted the tumor-stromal crosstalk by suppressing the STAT3-EMT signaling axis. Our study identifies STAT3 as a key regulator of CA-MSCs-induced OC progression and highlights the therapeutic potential of GZFL, which targets the STAT3-mediated tumor-stromal crosstalk. Our findings provide crucial mechanistic basis for advancing the clinical application of GZFL for the treatment of metastatic OC.