Magic™ Anti-BRCA1 (Phospho S1524) polyclonal Antibody

Objective: Neoadjuvant concurrent chemoradiotherapy (CCRT) followed by surgery is now the standard care for patients with advanced rectal cancer. Because a certain proportion of these patients have poor response to CCRT, the risk stratification of survival outcomes needs to be investigated. DNA repair responses in tumor cells can regulate malignant potential and therapy resistance. In this study, we analyzed the clinical significance of principal DNA repair effectors in patients with rectal cancer. Methods: We applied data mining for DNA repair pathways in a published transcriptome for rectal cancer cases, and identified that tumors with BRCA2 downregulation correlated with poor response to CCRT. We next examined BRCA2 expression by using immunohistochemistry staining in tumor tissues of 172 patients with rectal cancer. The correlation between BRCA2 expression levels and clinical variables was further analyzed in this rectal cancer cohort. Results: Among clinical and pathological factors, low BRCA2-expression was significantly correlated with higher pre-treatment (Tx) tumor status (P = .013), post-Tx tumor (P < .001) and nodal status (P = .044), vascular invasion (P = .008), and poor tumor regression grades (P < .001). In analyses of survival outcomes, patients with low BRCA2-expression were associated with shorter local recurrence-free survival (LRFS; P = .0005) and disease-specific survival (P = .0269). Multivariate analyses confirmed the independent prognostic value of low BRCA2-expression for shorter LRFS (P = .045, hazard ratio = 4.695). Conclusion: Low BRCA2-expression is a significant predictor for tumors in advanced stages, poor response to CCRT, and shorter survivals in patients with rectal cancer. Poly (adenosine diphosphate-ribose) polymerase inhibitors targeting DNA repair response in cells have demonstrated clinical efficacy in BRCA2-mutated patients with cancer. Further studies evaluating the efficacy of CCRT combined with these inhibitors in low BRCA2-expressing rectal cancers are encouraged.

Importance The value of platinum-based adjuvant chemotherapy in patients with triple-negative breast cancer (TNBC) remains controversial, as does whether BRCA1 and BRCA2 (BRCA1/2) germline variants are associated with platinum treatment sensitivity. Objective To compare 6 cycles of paclitaxel plus carboplatin (PCb) with a standard-dose regimen of 3 cycles of cyclophosphamide, epirubicin, and fluorouracil followed by 3 cycles of docetaxel (CEF-T). Design, Setting, and Participants This phase 3 randomized clinical trial was conducted at 9 cancer centers and hospitals in China. Between July 1, 2011, and April 30, 2016, women aged 18 to 70 years with operable TNBC after definitive surgery (having pathologically confirmed regional node-positive disease or node-negative disease with tumor diameter >10 mm) were screened and enrolled. Exclusion criteria included having metastatic or locally advanced disease, having non-TNBC, or receiving preoperative anticancer therapy. Data were analyzed from December 1, 2019, to January 31, 2020, from the intent-to-treat population as prespecified in the protocol. Interventions Participants were randomized to receive PCb (paclitaxel 80 mg/m(2)and carboplatin [area under the curve = 2] on days 1, 8, and 15 every 28 days for 6 cycles) or CEF-T (cyclophosphamide 500 mg/m(2), epirubicin 100 mg/m(2), and fluorouracil 500 mg/m(2)every 3 weeks for 3 cycles followed by docetaxel 100 mg/m(2)every 3 weeks for 3 cycles). Main Outcomes and Measures The primary end point was disease-free survival (DFS). Secondary end points included overall survival, distant DFS, relapse-free survival, DFS in patients with germline variants in BRCA1/2 or homologous recombination repair (HRR)-related genes, and toxicity. Results A total of 647 patients (mean [SD] age, 51 [44-57] years) with operable TNBC were randomized to receive CEF-T (n = 322) or PCb (n = 325). At a median follow-up of 62 months, DFS time was longer in those assigned to PCb compared with CEF-T (5-year DFS, 86.5% vs 80.3%, hazard ratio [HR] = 0.65; 95% CI, 0.44-0.96; P = .03). Similar outcomes were observed for distant DFS and relapse-free survival. There was no statistically significant difference in overall survival between the groups (HR = 0.71; 95% CI, 0.42-1.22, P = .22). In the exploratory and hypothesis-generating subgroup analyses of PCb vs CEF-T, the HR for DFS was 0.44 (95% CI, 0.15-1.31; P = .14) in patients with the BRCA1/2 variant and 0.39 (95% CI, 0.15-0.99; P = .04) in those with the HRR variant. Safety data were consistent with the known safety profiles of relevant drugs. Conclusions and Relevance These findings suggest that a paclitaxel-plus-carboplatin regimen is an effective alternative adjuvant chemotherapy choice for patients with operable TNBC. In the era of molecular classification, subsets of TNBC sensitive to PCb should be further investigated.