GANT61

Mantle cell lymphoma (MCL) is a rare and aggressive form of non‐Hodgkin lymphoma. Challenges in its treatment include relapse, drug resistance, and a short survival period. The Hedgehog/GLI1 (Hh/GLI1) and Wnt/β‐catenin pathways are crucial in cancer cell proliferation, survival, and drug resistance, making them significant targets for anticancer research. This study aimed to assess the effectiveness of combining inhibitors for both pathways against MCL and investigate the underlying molecular mechanisms. The co‐expression of key proteins from the Hh/GLI1 and Wnt/β‐catenin pathways was observed in MCL. Targeting the Hh/GLI1 pathway with the GLI1 inhibitor GANT61 and the Wnt/β‐catenin pathway with the CBP/β‐catenin transcription inhibitor ICG‐001, dual‐target therapy was demonstrated to synergistically suppressed the activity of MCL cells. This approach promoted MCL cell apoptosis, induced G0/G1 phase blockade, decreased the percentage of S‐phase cells, and enhanced the sensitivity of MCL cells to the drugs adriamycin and ibrutinib. Both GANT61 and ICG‐001 downregulated GLI1 and β‐catenin while upregulating GSK‐3β expression. The interaction between Hh/GLI1 and Wnt/β‐catenin pathways was mediated by GANT61‐dependent Hh/GLI1 inhibition. Moreover, GLI1 knockdown combined with ICG‐001 synergistically induced apoptosis and increased drug sensitivity of MCL cells to doxorubicin and ibrutinib. GANT61 attenuated the overexpression of β‐catenin and decreased the inhibition of GSK‐3β in MCL cells. Overall, the combined targeting of both the Hh/GLI1 and Wnt/β‐catenin pathways was more effective in suppressing proliferation, inducing G0/G1 cycle retardation, promoting apoptosis, and increasing drug sensitivity of MCL cells than mono treatments. These findings emphasize the potential of combinatorial therapy for treating MCL patients.

Glioblastoma (GBM) aggressiveness is partly driven by the reactivation of signaling pathways such as Sonic hedgehog (SHH) and the interaction with its microenvironment. SHH pathway activation is one of the phenomena behind the glial transformation in response to tumor growth. The reactivation of the SHH signaling cascade during GBM–astrocyte interaction is highly relevant to understanding the mechanisms used by the tumor to modulate the adjacent stroma. The role of reactive astrocytes considering SHH signaling during GBM progression is investigated using a 3D in vitro model. T98G GBM spheroids displayed significant downregulation of SHH (61.4 ± 9.3%), GLI‐1 (6.5 ± 3.7%), Ki‐67 (33.7 ± 8.1%), and mutant MTp53 (21.3 ± 10.6%) compared to the CONTROL group when incubated with conditioned medium of reactive astrocytes (CM‐AST). The SHH pathway inhibitor, GANT‐61, significantly reduced previous markers (SHH = 43.0 ± 12.1%; GLI‐1 = 9.5 ± 3.4%; Ki‐67 = 31.9 ± 4.6%; MTp53 = 6.5 ± 7.5%) compared to the CONTROL, and a synergistic effect could be observed between GANT‐61 and CM‐AST. The volume (2.0 ± 0.2 × 107 µm³), cell viability (80.4 ± 3.2%), and migration (41 ± 10%) of GBM spheroids were significantly reduced in the presence of GANT‐61 and CM‐AST when compared to CM‐AST after 72 h (volume = 2.3 ± 0.4 × 107 µm³; viability = 92.2 ± 6.5%; migration = 102.5 ± 14.6%). Results demonstrated that factors released by reactive astrocytes promoted a neuroprotective effect preventing GBM progression using a 3D in vitro model potentiated by SHH pathway inhibition.