Journal: Frontiers in Oncology
Article Title: Inhibition of ATM or ATR in combination with hypo-fractionated radiotherapy leads to a different immunophenotype on transcript and protein level in HNSCC
doi: 10.3389/fonc.2024.1460150
Figure Lengend Snippet: Flow cytometric analysis of immune checkpoint surface marker on HNSCC after ATMi or ATRi w/o 2x5Gy RT. Combining RT with ATRi leads to the upregulation of immunostimulatory ICOS-L and CD137-L on HNSCC cells, irrespective of the HPV status. 48 hours after the last treatment, the HNSCC cells were harvested and the expression of immunostimulatory ICMs ICOS-L and CD137-L was examined by flow cytometry. The gating strategy is presented in (A) ICM expression is presented as ΔMFI (delta of mean fluorescence intensity of stained samples – background fluorescence) (B, C) . The combined treatment of RT and ATRi increased ICOS-L expression in all four cell lines compared to ATRi or RT alone, as well as in comparison to RT combined with ATMi (B) . Dual treatment with RT and ATMi tended to even decrease ICOS-L surface expression compared to RT or RT with ATRi (B) . RT and ATRi led to enhanced expression of immunostimulatory CD137-L in HPV-negative HSC4 cells compared to ATRi or RT alone, or the combined treatment of RT and ATMi (C) . In HPV-positive UM-SCC-47 and UD-SCC-2 cells, the combination of RT and ATRi also demonstrated higher surface expression of CD137-L compared to RT alone or treatment with RT and ATMi, respectively (C) . A one-tailed Mann-Whitney U test was performed to compare the different treatment approaches within one cell line: *p ≤ 0.05, n=4.
Article Snippet: Two HPV-negative HSC4 (RRID: CVCL_1289), Cal-33 (RRID: CVCL_1108) and two HPV-positive UM-SCC-47 (RRID: CVCL_7759), UD-SCC-2 (RRID: CVCL_E325) HNSCC cell lines were generously provided by Dr. Thorsten Rieckmann at the University Medical Center Hamburg-Eppendorf.
Techniques: Marker, Expressing, Flow Cytometry, Fluorescence, Staining, Comparison, One-tailed Test, MANN-WHITNEY