Prognostic Value And Efficacy Treated With Platinum-based Chemotherapy Of The Expression Of DNA Repair-related Biomarkers Mediated By Alcohol In Gastric Cancer Patients

Purpose Alcohol consumption is related to gastric cancer(GC)and is thought to induce carcinogenesis through deregulation of RNA polymerase(Pol)III genes and oxidative damage.TFIIB related factor 1(BRF1)regulates RNA Pol III gene transcription,and overexpression of BRF1 alleviates the inhibition of RNA Pol III transcription through breast cancer susceptibility gene 1(BRCA1).Myeloperoxidase(MPO)involvement in cancer is induced by alcohol-mediated oxidative damage.Furthermore,BRCA1/2,Excision repair cross-complementing gene-1(ERCC1)and MPO play key roles in DNA repair.BRCA2 exerts a different role from BRCA1 in homologous recombination repair(HR).BRCA1 primarily acts at proximal steps that signal the presence of these lesions and helps initiate their repair via HR,whereas BRCA2 stabilizes the structure at the replication-associated lesions and works directly to resolve the lesions with HR by controlling the activity and assembly of the essential recombination enzyme RAD51.ERCC1 and MPO are critical enzymes in the nucleotide excision repair(NER)pathway.NER corrects damaged DNA structures induced by the formation of platinum-DNA adducts.It is significant that BRCA1,BRCA2,ERCC1 and MPO are likely to be associated with the efficacy of platinum-based chemotherapy.Meanwhile,BRF1,BRCA1,BRCA2 and MPO protein are involved in the development of GC,which may affect the prognosis of patients with GC.It is remarkable to use peripheral blood lymphocytes instead of tumor tissue to detect expression of ERCC1 to predict efficacy of platinum-based chemotherapy.Methods In this study,77 tumor and 69 para-tumor tissues were isolated from 77 primary gastric adenocarcinoma resections.57 of the patients who underwent radical surgery received platinum-based adjuvant chemotherapy.Among them,peripheral blood specimens were collected from 48 patients.We detected BRF1,BRCA1/2,ERCC1 and MPO in human biopsies of tumor tissues or peripheral blood lymphocytes from GC cases using Immunohistochemistry,Immunocytochemistry and Immunofluorescence.Specifically,we aimed to assess the correlation between protein expression and clinicopathological features,especially alcohol consumption;compare protein expression between GC tumor and para-tumor tissues;examine the correlation and co-localization between related protein expression;evaluate the correlation between protein expression and prognosis;demonstrate the correlation between protein expression and the survival of patients with GC who have received platinum-based adjuvant chemotherapy;and analyze the correlation of ERCC1 expression in peripheral blood lymphocytes with outcomes of patients with GC treated with oxaliplatin-based adjuvant chemotherapy.Results We found that BRF1 and BRCA2 proteins were located in the tumor cell nucleus and cytoplasm.And BRCA1 and ERCC1 proteins were detected in the tumor cell nucleus.Intriguingly,MPO-positive inflammatory cell infiltration was discovered in the GC tissues.BRF1 staining was observed in all 77 GC tissues,and the positive BRCA1/2and ERCC1 expression rates were 62.3%(48/77)and 72.9%(35/48).Expression of ERCC1 was found in 56.3%(27/48)from peripheral blood lymphocytes.MPO-positive inflammatory cell infiltration was discovered in 61.0%(47/77)of GC tissues.Furthermore,the median positive H-scores for BRF1,BRCA1 and BRCA2 were70%(5%-240%),120%(10%-270%)and 100%(20%-240%),respectively.High BRF1 and BRCA1/2 expressions were observed in 46.8%(36/77)and 26.0%(20/77)of GC tissues,respectively.BRF1 expression was significantly associated with tumor stage (p=0.023)and lymph node metastasis(p=0.005).BRCA2 expression was also significantly associated with lymph node metastasis(p=0.004).There were no relationships between BRCA1/ERCC1 and clinicopathological factors.Moreover,BRF1(p=0.010)overexpression and MPO(p=0.015)-positive cell infiltration were more frequent in GC patients with hazardous or harmful alcohol consumption habits.In para-tumor tissues,positive BRF1,BRCA1 and BRCA2 expression rates of 73.9%(51/69),26.1%(18/69)and 30.4%(21/69),respectively,were observed.The MPO-positive cell infiltration rate was 26.1%(18/69).In particular,positive BRCA1 expression in para-tumor tissues was more frequent in GC patients with hazardous or harmful alcohol consumption habits.There were no relationships between BRF1/BRCA2/MPO in para-tumor tissues from GC patients and clinicopathological factors.The H-scores for BRF1(Z=-5.162,p<0.001),BRCA1(Z=-5.120,p<0.001)and BRCA2(Z=-4.164,p<0.001)in GC patient tumor tissues were significantly higher than those in para-tumor tissues.And MPO-positive cell infiltration degrees(Z=-4.083,p<0.001)in GC patient tumor tissues were significantly higher than those in para-tumor tissues.The correlation was statistically significant regarding the expression of BRCA1/2 in GC patient tumor tissues(r=0.696,p<0.001)and para-tumor tissues(r=0.715,p<0.001).Co-localization of BRF1 and BRCA1 in the nucleus was confirmed by immunofluorescence.Patients with low BRF1 expression displayed better DFS(18vs.9 months,p=0.003)and OS(24 vs.16 months,p=0.006)compared to patients with high BRF1 expression.The DFS(BRCA1: 8 vs.15 months,p=0.005 and BRCA2: 8 vs.18 months,p<0.001)and OS(BRCA1: 14 vs.23 months,p<0.001 and BRCA2: 13 vs.24 months,p<0.001)of patients with high BRCA1/2 expression were significantly shorter than patients with low and negative BRCA1/2 expression.Additionally,the presence of MPO-positive cell infiltration was significantly related to poor DFS(9 vs.18 months,p=0.013)and OS(18 vs.27 months,p=0.034)compared to the absence of MPO-positive cell infiltration.Univariate Cox proportional hazard regression analysis showed that BRF1 expression(p=0.021),BRCA2 expression(p<0.001)and MPO-positive inflammatory cell infiltration(p=0.039)were independent prognostic factors in GC patients and were significantly associated with DFS.BRCA1(p=0.005)and BRCA2(p<0.001)expression levels were also independent prognostic factors for OS.On the other hand,patients who had received platinum-based adjuvant chemotherapy and who showed negative or low BRCA1/2 expression had significantly longer DFS(BRCA1: 18 vs.9 months,p=0.010 and BRCA2: 18 vs.8 months,p<0.001)and OS(BRCA1: 26 vs.16 months,p=0.003 and BRCA2: 30 vs.14 months,p<0.001)compared to patients with high BRCA1/2 expression.Moreover,patients who received platinum-based adjuvant chemotherapy and had no MPO-positive inflammatory cell infiltration demonstrated longer DFS(18 vs.10 months,p=0.080)and OS(30 vs.20 months,p=0.137)compared to patients with MPO-positive inflammatory cell infiltration in GC tissues.Unfortunately,this trend did not translate to a significant improvement in survival.Patients with negative expression of ERCC1 in tumor tissues had a significantly longer DFS(18 vs.10 months,P = 0.006)and OS(30 vs 17 months,P = 0.012)compared to patients with positive expression of ERCC1.In peripheral blood lymphocytes,high expression of ERCC1 was associated with decreased DFS(9 vs.18 months,P = 0.032),but not OS(16 vs.24 months,P = 0.057).In the multivariate analysis,BRCA2 was an independent prognostic factor for DFS(p<0.001)and OS(p<0.001)in GC patients who received platinum-based adjuvant chemotherapy.Conclusion BRF1,BRCA1/2 and MPO are DNA repair-related biomarkers induced by alcohol with prognostic value in GC patients.Patients with GC exhibiting negative expression of ERCC1 are more likely to benefit from oxaliplatin-based adjuvant chemotherapy.