DNA damage repair and survival outcomes in advanced gastric cancer patients treated with first-line chemotherapy

Abstract

The DNA damage response (DDR) network is exploited by cancer cells to withstand chemotherapy. Gastric cancer (GC) carries deregulation of the DDR and harbors genetic defects that fuel its activation. The ATM-Chk2 and ATR-Chk1-Wee1 axes are deputed to initiate DNA repair. Overactivation of these pathways in cancer cells may represent an adaptive response for compensating genetic defects deregulating G 1 -S transition (e.g., TP53) and ATM/ATR-initiated DNA repair (e.g., ARID1A). We hypothesized that DDR-linked biomarkers may predict clinical outcomes in GC patients treated with chemotherapy. Immunohistochemical assessment of DDR kinases (pATM, pChk2, pChk1 and pWee1) and DNA damage markers (c-H2AX and pRPA32) was performed in biological samples from 110 advanced GC patients treated with first-line chemotherapy, either in phase II trials or in routine clinical practice. In 90 patients, this characterization was integrated with targeted ultra-deep sequencing for evaluating the mutational status of TP53 and ARID1A. We recorded a positive association between the investigated biomarkers. The combination of two biomarkers (c-H2AX high /pATM high ) was an adverse factor for both progression-free survival (multivariate Cox: HR 2.23, 95%CI: 1.47-3.40) and overall survival (multivariate Cox: HR: 2.07, 95%CI: 1.20-3.58). The relationship between the c-H2AX high /pATM high model and progression-free survival was consistent across the different TP53 backgrounds and was maintained in the ARID1A wild-type setting. Conversely, this association was no longer observed in an ARID1A-mutated subgroup. The c-H2AX high /pATM high model negatively impacted survival outcomes in GC patients treated with chemotherapy. The mutational status of ARID1A, but apparently not TP53 mutations, affects its predictive significance.Key words: DNA damage repair, g-H2AX, pATM, TP53, ARID1A Abbreviations: ATM: ataxia-telangiectasia mutated; ATR: ataxia telangiectasia and rad3-related protein; Chk1: checkpoint kinase 1; Chk2: checkpoint Kinase 2; DDR: DNA damage and repair; DNA DSBs: DNA double-strand breaks; DNA SSBs: DNA single-strand breaks; OS: overall survival; g-H2AX: phosphorylated H2A histone family member X; PFS: progression-free survival; pRPA32: phosphorylated replication protein A2; Wee1: Wee1-like protein kinase Additional Supporting Information may be found in the online version of this article. Livia Ronchetti, Elisa Melucci, Francesca De Nicola and Frauke Goeman contributed equally to this work. Ruggero De Maria and Marcello Maugeri-Sacc a share senior authorship MM-S and RDM conceived and designed the study. LR, EM, BC, CAA, EG, EP, MGD, SB and MM were involved in molecular pathology analysis. FDN, FG and MF carried out targeted DNA deep sequencing. FS, MP, IT and MB performed bioinformatic and statistical analyses. LP, PV, DS and LDL acquired the data related to clinical features, treatment administered and therapeutic outcomes. IV was involved in study design and provided critical revision of the manuscript for important intellectual con...

Coexisting YAP expression and TP53 missense mutations delineates a molecular scenario unexpectedly associated with better survival outcomes in advanced gastric cancer

“…This is consistent with a mutational pattern necessary to encode a protein able to interact with YAP. It is worth mentioning that in a molecularly-focused multivariate Cox regression analysis, the YAP+/ TP53 mut(mv) model was associated with a decreased risk of disease progression independently from the two other signatures we had previously identified [1, 9]. The observation that the three signatures retained their predictive value enables us to exclude potential confounding factors.…”

“…Taking into account the multi-level interaction between the Hippo signaling cascade and p53 family members [8], in our opinion a deeper molecular characterization is needed to fully appreciate the clinical implications of such cooperation. To address this issue, we designed a prospective study with biomarker validation purposes on the basis of our previous results [1, 9]. The trial envisions an extensive genomic and transcriptomic analysis that will enable us to carry out an integrated pathway-focused analysis.…”

“…Samples had been already characterized for the expression of a battery of protein- and gene-level biomarkers, also including YAP assessed by immunohistochemistry (IHC) and TP53 mutations evaluated through targeted DNA next-generation sequencing (NGS) [1, 9]. A detailed description of reagents, procedures and statistical analyses was provided elsewhere [1, 9], whereas baseline characteristics of GC included in this analysis are detailed in the Additional file 1.…”

“…The protective significance of the YAP+/TP53 mut(mv) model was retained in a multivariate Cox regression analysis built by adjusting for other plausible predictors of PFS (HR 0.53, 95% CI 0.30–0.91, p = 0.022) (Table 1). We have previously described two other signatures associated with adverse survival outcomes, the first denoting the TAZ/Wnt pathway crosstalk (TAZ pos /WNT mut) and the second indicating the activation of the DNA damage response (DDR) network (γ-H2AX pos /pATM pos ) [1, 9]. Thus, we verified whether the protective role of the YAP+/TP53 mut(mv) model was maintained also when taking into account the two aforementioned molecular backgrounds.…”

FBLIM1 enhances oral cancer malignancy via modulation of the epidermal growth factor receptor pathway

“…The intensity of the stained cells was classified into four levels, with 0+ indicating negative; 1+, low positive; 2+, positive; and 3+, high positive. FBLIM1 was classified as positive and negative using the median score of all tumors as the cut‐off points . Cases with a score over 118.03 were considered FBLIM1‐positive.…”