F SMO [147]. Similarly, ASPP2 depletionBiomedicines 2021, 9,27 ofin gallbladder cancer cell lines was shown to boost the expression and binding of aPKC with GLI1. Consequently, aPKC phosphorylated GLI1 Ser84, which, in turn, promoted its nuclear translocation to activate cytokine genes (CCL2, CCL5, and TNF) involved inside the recruitment of tumorassociated macrophages (TAMs). Consequently, elevated TAMs recruitment promoted EMTlike adjustments in gallbladder cancer tissues and enhanced their tumor lung metastases in vivo. In addition, coculture of gallbladder cancer cells with macrophages or a macrophagederived conditioned medium enhanced cell migration with a concomitant increase in mesenchymal Ncadherin and vimentin and a reduce in epithelial marker Ecadherin. Interestingly, GLI1 also can regulate PRKCI (gene encoding aPKC) by straight binding to its promoter region, implying the existence of a constructive feedback loop. Of note, SMO inhibition by both cyclopamine and siRNAmediated knockdown had no substantial impact on GLI1 expression in gallbladder cancer cells, suggesting SMOindependent, aPKCmediated GLI1 activation [126]. Transcription factor SOX9, a novel cancer stem cell marker, expression was shown to be regulated by GLI1 to promote CSC options in PDAC PANC1 cells. The CSC spheroids were enriched for GLI1 regulatory genes (GLI1, GLI2, SOX9, and SNAI1) and pancreatic CSC markers (CD24, CD44, ESA, CD133 and CXCR4, OCT4, and KLF4). The suppression of either SOX9 or GLI1 impaired CSC markers’ expression with incredibly equivalent profiles. In addition, SOX9 suppression considerably impaired spheroid formation and side population cells. SOX9 suppression also substantially attenuated PDAC cell proliferation, anchorage independence, and survival. Conversely, restoring GLI1 expression by siRNAmediated knockdown of TrCP, a negative regulator of GLI1, rescued cell death induced by SOX9 deficiency. Conversely, cosuppression of GLI1 and SOX9 additional enhanced cell death [115]. Mechanistically, SOX9 inhibited the function of TrCP, a negative regulator of GLI, by binding to certain protein motifs (Fbox area) present within the TrCP subunit, Thalidomide D4 Epigenetics thereby disrupting its interaction with GLI protein. On top of that, SOX9 interfered with the TrCP function by blocking its interaction with SKP1, an essential subunit in the SCFTrCP complex, and tethering it inside the nucleus of PDAC cells to protect nuclear GLI1 from degradation. Notably, a good feedback loop among SOX9 and GLI1 has been reported. To provide higher clinical relevance to human physiology, the authors assessed the expression of SOX9 and TrCP expression in key human PDAC specimens by utilizing Oncomine microarray data, and as noticed in their research, SOX9 mRNA upregulation was accompanied by downregulation of BTRC (encodes for TrCP), suggesting a potential for SOX9mediated GLI1 upregulation by means of downregulation of TrCP [115]. Transcription element forkhead box C1 (FOXC1), a recognized inducer of oncogenesis in breast cancer, has been reported to be overexpressed in basallike breast cancer (BLBC) to promote CSC traits. Notably, improved levels of FOXC1 have been connected using the upregulation of GLI2 protein accompanied by an increased BLBC stemlike phenotype. FOXC1mediated upregulation of ALDH1 activity and mammosphere formation capacity was significantly attenuated by GLI2 knockdown in Bopindolol Neuronal Signaling MDAMB231 cells. Interestingly, the ectopic expression of mouse GLI2, whose expression was not affected by GLI2 shRNA, c.