Fig. 3: L412F polymorphism prevents TLR3-induced cell death.
From: The TLR3 L412F polymorphism prevents TLR3-mediated tumor cell death induction in pediatric sarcomas
A Treatment with Poly(I:C) does not trigger RD cell death in vitro. Viability of RD rhabdomyosarcoma (RMS) cells treated or not with IFN-1 and/or Poly(I:C) for 72 h was analyzed by cytometry (DAPI/Acridine Orange). Mean values ± s.t.d are represented (n = 3, p-value = 0.35). B Homozygous status for the L412F variant of TLR3 correlates with Poly(I:C) insensitivity in pediatric Osteosarcoma (SaOS-2, MNNG/HOS), Rhabdomyosarcoma (RD, RH30, RMS-CLB1) and Neuroblastoma (SK-N-AS) cell lines. C, D Expression of one TLR3 L412 allele is sufficient to restore sensitivity of RD cells to Poly(I:C). L412 allele was inserted in two RD clones using a CRISPR-Cas9 Knock-In strategy, respectively termed RD-KI-L412F-Clone1 (C) and RD-KI-L412F-Clone2 (D). Cells were treated with IFN-1 and/or Poly(I:C) for 72 h, using DAPI/Acridine Orange. Mean values ± s.t.d are represented (RD-KI-L412F-Clone1, n = 4, *p-value = 0.0143; RD-KI-L412F-Clone2, n = 3, *p-value = 0.05). E Percentage of homozygous individuals is higher in a cohort of children and AYA with RMS than in the general population. TLR3 L412 variant status was defined in the St Jude RMS cohort relative to the GnomAD v3.1.2 cohort of healthy individuals (*p-value = 0.0289, two-tailed Fisher’s exact test).
