Project description:Stromal cell senescence plays a crucial role in activating cancer-associated fibroblasts (CAFs). The Androgen receptor (AR) function oversees cellular senescence and CAF activation. Here, we identify the mesenchymal-specific transcriptional coregulator ANKRD1 as a key driver of CAF conversion. ANKRD1 is strongly upregulated in CAFs and under direct negative control of AR, and its loss impairs the pro-tumorigenic potential of CAFs. ANKRD1 controls a CAF-specific gene expression program and is associated with poorer survival of HNSCC, lung, and cervical SCC patients. Mechanistically, ANKRD1 binds to the chromatin on CAF gene regulatory regions in a complex with the AP1 transcription factor family. We show that ANKRD1 enhances the AP1 DNA binding activity to CAF gene promoters. Targeting ANKRD1 with the FANA antisense oligonucleotides reverts CAFs into a normal fibroblast, disrupts AP1 complex formation, and blocks CAF’s pro-tumorigenic potential in an orthotopic model of SCC, thus representing an exciting target for stroma-oriented cancer therapy.
Project description:Stromal cell senescence plays a crucial role in activating cancer-associated fibroblasts (CAFs). The Androgen receptor (AR) function oversees cellular senescence and CAF activation. Here, we identify the mesenchymal-specific transcriptional coregulator ANKRD1 as a key driver of CAF conversion. ANKRD1 is strongly upregulated in CAFs and under direct negative control of AR, and its loss impairs the pro-tumorigenic potential of CAFs. ANKRD1 controls a CAF-specific gene expression program and is associated with poorer survival of HNSCC, lung, and cervical SCC patients. Mechanistically, ANKRD1 binds to the chromatin on CAF gene regulatory regions in a complex with the AP1 transcription factor family. We show that ANKRD1 enhances the AP1 DNA binding activity to CAF gene promoters. Targeting ANKRD1 with the FANA antisense oligonucleotides reverts CAFs into a normal fibroblast, disrupts AP1 complex formation, and blocks CAF’s pro-tumorigenic potential in an orthotopic model of SCC, thus representing an exciting target for stroma-oriented cancer therapy.
Project description:Stromal cell senescence plays a crucial role in activating cancer-associated fibroblasts (CAFs). The Androgen receptor (AR) function oversees cellular senescence and CAF activation. Here, we identify the mesenchymal-specific transcriptional coregulator ANKRD1 as a key driver of CAF conversion. ANKRD1 is strongly upregulated in CAFs and under direct negative control of AR, and its loss impairs the pro-tumorigenic potential of CAFs. ANKRD1 controls a CAF-specific gene expression program and is associated with poorer survival of HNSCC, lung, and cervical SCC patients. Mechanistically, ANKRD1 binds to the chromatin on CAF gene regulatory regions in a complex with the AP1 transcription factor family. We show that ANKRD1 enhances the AP1 DNA binding activity to CAF gene promoters. Targeting ANKRD1 with the FANA antisense oligonucleotides reverts CAFs into a normal fibroblast, disrupts AP1 complex formation, and blocks CAF’s pro-tumorigenic potential in an orthotopic model of SCC, thus representing an exciting target for stroma-oriented cancer therapy.
Project description:The tumor microenvironment is essential for cancer progression, yet the nuclear mechanisms that reprogram stromal fibroblasts into cancer-associated fibroblasts (CAFs) remain to be defined. Here, we identify a telomere-derived RNA–protein signaling axis that links genome integrity and fibroblast plasticity. We show that the long non-coding RNA TERRA, transcribed from telomeres, is upregulated in CAFs across multiple human skin cancers following loss of androgen receptor (AR) expression. Elevated TERRA enhances telomeric DNA damage and activates a CAF-specific transcriptional program. Through proteomic profiling, we identify the RNA-binding protein NONO as a critical TERRA effector. TERRA and NONO form nuclear complexes selectively in CAFs, while in normal fibroblasts NONO associates with AR. Disruption of the TERRA-NONO complex, either by genetic silencing or a small-molecule inhibitor of NONO, reverses CAF activation and suppresses tumor-stroma cells expansion in vitro and in vivo. These findings uncover a telomere-encoded mechanism of stromal reprogramming and identify the TERRA–NONO complex as a targetable point of vulnerability in the tumor microenvironment.
Project description:The tumor microenvironment is essential for cancer progression, yet the nuclear mechanisms that reprogram stromal fibroblasts into cancer-associated fibroblasts (CAFs) remain to be defined. Here, we identify a telomere-derived RNA–protein signaling axis that links genome integrity and fibroblast plasticity. We show that the long non-coding RNA TERRA, transcribed from telomeres, is upregulated in CAFs across multiple human skin cancers following loss of androgen receptor (AR) expression. Elevated TERRA enhances telomeric DNA damage and activates a CAF-specific transcriptional program. Through proteomic profiling, we identify the RNA-binding protein NONO as a critical TERRA effector. TERRA and NONO form nuclear complexes selectively in CAFs, while in normal fibroblasts NONO associates with AR. Disruption of the TERRA-NONO complex, either by genetic silencing or a small-molecule inhibitor of NONO, reverses CAF activation and suppresses tumor-stroma cells expansion in vitro and in vivo. These findings uncover a telomere-encoded mechanism of stromal reprogramming and identify the TERRA–NONO complex as a targetable point of vulnerability in the tumor microenvironment.
Project description:Cellular senescence is a complex biological process that contributes to wound healing, carcinogenesis, and age-related disease. Although the molecular mechanisms whereby senescence promotes wound repair are not well understood, the protein ANKRD1, which promoted wound healing in mice, was found to increase in senescent cells. We hypothesized that ANKRD1 may play a role in senescence-mediated wound healing. Conditioned medium (CM) from senescent WI-38 human diploid fibroblasts hastened cell migration of human HaCaT keratinocytes. Interestingly, silencing ANKRD1 in WI-38 cells reduced the effect of CM on cell migration, while overexpressing ANKRD1 accelerated it. Further proteomic analysis revealed that ANKRD1 associates with YBOX1, a multifunctional protein that modulates transcription of the ELN gene and reduces ELN mRNA production. The product of the ELN gene, the protein ELN or tropoelastin (a subunit of elastin), is a secreted factor that reduces motility. Thus, we propose that a rise in ANKRD1 during early senescence transiently limits the YBOX1-dependent transcriptional increase in ELN production, and thereby enables cell motility in early phases of senescence.