Benyao Lin

p53 Codon 72 Polymorphism Predicts the Pathologic Response to Neoadjuvant Chemotherapy in Patients with Breast Cancer

Purpose: Recent studies have highlighted that the p53 codon 72 polymorphism plays a crucial role in modulating wild-type p53 apoptotic capacity, and as such may influence the response to chemotherapy. Thus, the purpose of this study was to investigate whether the p53 codon 72 polymorphism might influence pathologic response to neoadjuvant chemotherapy in primary breast cancer. Experimental Design: One hundred and ten operable breast cancer patients received anthracycline-based neoadjuvant chemotherapy and p53 codon 72 polymorphism status was analyzed by PCR-RFLP. Results: The distribution of initial clinical stage, tumor size, estrogen receptor or progesterone receptor status, menopausal status, or erbB2 expression was not significantly different among the polymorphic variants. However, we found that only 13% (3 of 23) of patients with the Pro/Pro variant had a good pathologic response, defined as a complete pathologic response or minimal residual disease. In comparison, 40% (22 of 55) or 37.5% (12 of 32) of patients with the Pro/Arg or Arg/Arg variant had a good pathologic response (P = 0.019). Moreover, patients with the Pro/Pro variant were more likely to have a positive axillary lymph node status than those with the Pro/Arg or Arg/Arg variant (P = 0.007). Furthermore, in multivariate analysis, p53 codon 72 polymorphism was found to be a strong predictor of pathologic response (odds ratio 6.7, 95% confidence interval, 1.4-31.2; P = 0.016). Conclusion: Our study indicates that breast cancer patients with the Pro/Pro variant may be less sensitive to anthracycline-based treatment than those with the Pro/Arg or Arg/Arg variant and suggests that analysis of p53 codon 72 polymorphism may provide a simple predictive marker for selecting the right breast cancer patients to anthracycline-based neoadjuvant chemotherapy in clinical setting.

Mutations in RECQL Gene Are Associated with Predisposition to Breast Cancer.

The genetic cause for approximately 80% of familial breast cancer patients is unknown. Here, by sequencing the entire exomes of nine early-onset familial breast cancer patients without BRCA1/2 mutations (diagnosed with breast cancer at or before the age of 35) we found that two index cases carried a potentially deleterious mutation in the RECQL gene (RecQ helicase-like; chr12p12). Recent studies suggested that RECQL is involved in DNA double-strand break repair and it plays an important role in the maintenance of genomic stability. Therefore, we further screened the RECQL gene in an additional 439 unrelated familial breast cancer patients. In total, we found three nonsense mutations leading to a truncated protein of RECQL (p.L128X, p.W172X, and p.Q266X), one mutation affecting mRNA splicing (c.395-2A>G), and five missense mutations disrupting the helicase activity of RECQL (p.A195S, p.R215Q, p.R455C, p.M458K, and p.T562I), as evaluated through an in vitro helicase assay. Taken together, 9 out of 448 BRCA-negative familial breast cancer patients carried a pathogenic mutation of the RECQL gene compared with one of the 1,588 controls (P = 9.14×10-6). Our findings suggest that RECQL is a potential breast cancer susceptibility gene and that mutations in this gene contribute to familial breast cancer development.

RAD51C germline mutations in Chinese women with familial breast cancer

To the Editor,Germline mutations in high penetrance breast cancer sus-ceptibility genes, BRCA1 and BRCA2, account for onlyapproximately 10% of Chinese familial breast cancers [1],indicating other susceptibility genes related to Chinesefamilial breast cancer may exist. RAD51C gene (Ras-related associated with diabetes) is located on chromosome17q23, a region that was found to be frequently amplifiedin breast tumors [2, 3]. RAD51C gene is a member of theRAD51 family and plays an essential role in homologousrecombination, DNA damage sensitivity, genomic integ-rity, embryonic development, activation of cell cyclecheckpoint kinase 2 (CHK2), and cell cycle arrest inresponse to DNA damage [4–8].Recently, a biallelic missense mutation in the RAD51Cgene was found in a family from Pakistan with Fanconianemia-like disorder [9]. In an accompanying article, sixmonoallelic deleterious mutations in the RAD51C genewere found in 480 BRCA1/2-negative breast/ovarian cancerfamilies from Germany [10]. This study provides the firstevidence to show that the RAD51C is a breast cancersusceptibility gene. Thus, the RAD51C gene may deserveto be comprehensively screened as a breast cancer sus-ceptibility gene in other populations.In this study, we screened the entire coding regions andexon–intron boundaries of the RAD51C gene in 273 Chi-nese women with familial breast cancer who do not carrymutations in BRCA1 and BRCA2 genes by polymerasechain reaction (PCR)-sequencing. Familial breast cancercases were from the Breast Center, Peking UniversityCancer Hospital from July 2006 to May 2010. The criteriaof familial breast cancer are (1) patients have at least one ormore first- or second-degree relatives affected with breastcancer and/or ovarian cancer regardless of age and (2)bilateral breast cancer regardless of age. Four hundredsseventy-five healthy Chinese women serve as controls.Both of the cases and controls are Han Chinese women andreside in the north of China. The whole coding sequencesof RAD51C were amplified using nine sets of primersdescribed elsewhere with a minor modification [10]. Allfragments were sequenced using BigDye Terminator CycleSequencing Kit and ABI 3730 automated sequencer(Applied Biosystems, Foster City, CA). Each mutation wasconfirmed by duplicate.In total, we detected eight germline sequence variants inthe RAD51C gene in the 273 BRCA1/2-negative familialbreast cancer cases. Among them, three were non-codingvariants and five were coding variants (Table 1). None ofthem were previously reported. Of the coding variants, onewas synomenous and four were non-synomenous. Amongthe four amino-acid substitution variants, 4C[G (R2G) waslocated in exon 1, 635G[A (R212H) and 644A[G(D215G) in exon 4, and 882G[C (Q294H) in exon 6. Themissense variants R2G, D215G, and Q294H were detectedin one index case, whereas R212H was detected in twounrelated cases. We then screened the four missense vari-ants in 475 healthy controls. The variant R212H was foundin two healthy individuals, indicating this variant wasunlikely to be pathogenic. In contrast, none of the

A recurrent CHEK2 p.H371Y mutation is associated with breast cancer risk in Chinese women.

The association between the CHEK2 and breast cancer risk in Chinese women is unknown. Here, we screened the full CHEK2 coding sequence in 118 Chinese familial breast cancer cases who are negative for mutations in BRCA1 and BRCA2, one recurrent mutation, CHEK2 c.1111C>T (p.H371Y), was identified in five index cases in this cohort. Functional analysis suggested that CHEK2 p.H371Y was a pathogenic mutation that resulted in decreased kinase activity. We further screened the CHEK2 p.H371Y mutation in 909 unselected breast cancer cases and 1,228 healthy individuals. The frequencies of the CHEK2 p.H371Y in familial and unselected breast cancer cases and controls were 4.24% (5/118), 1.76% (16/909), and 0.73% (9/1228), respectively. The p.H371Y mutation was significantly associated with increased breast cancer risk in unselected breast cancer (odds ratio [OR] 2.43, 95% confidence interval [CI] 1.07–5.52, P = 0.034). Our results indicate that the recurrent mutation, p.H371Y, confers a moderate risk of breast cancer in Chinese women. Hum Mutat 32:1–4, 2011.

Current Status of Diagnosis And Treatment of Primary Breast Cancer in Beijing, 2008

ObjectiveTo investigate the status of diagnosis and treatment of primary breast cancer in Beijing, 2008.MethodsAll the patients who were diagnosed as primary breast cancer in Beijing in 2008 were enrolled in this study. Information of these patients, including the features of tumors, clinical diagnosis and treatment was collected, and filled in the well-designed questionnaire forms by trained surveyors. The missing data were partly complemented through telephone interviews.ResultsA total of 3473 Beijing citizens were diagnosed as primary breast cancer (25 patients with synchronal bilateral breast cancer) in Beijing, 2008. Of them 82.09% were symptomatic. 19.02% and 34.11% were diagnosed using fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB), respectively. 15.92% received sentinel lymph node biopsy (SLNB) and 24.27% received breast conserving surgery (BCS). Among 476 cases with Her-2 positive, only 96 received anti-Her-2 therapy. We found that the standardization level varied in hospitals of different grades, with higher level in Grade-III hospitals. Of note, some breast cancer patients received non-standard primary tumor therapy: 65.63% of the patients with ductal carcinoma in situ (DCIS) received axillary lymph node dissection and 36.88% received chemotherapy; 25.89% of the patients underwent breast conserving surgery without margin status; 12.10% of the patients received chemotherapy less than 4 cycles.ConclusionAlthough most breast cancer patients received basic medical care, the mode of diagnosis and treatment should be improved and should be standardized in the future in Beijing.

Germline Mutations in Cancer Susceptibility Genes in a Large Series of Unselected Breast Cancer Patients

Purpose: The prevalence of mutations in cancer susceptibility genes such as BRCA1 and BRCA2 and other cancer susceptibility genes and their clinical relevance are largely unknown among a large series of unselected breast cancer patients in the Chinese population. Experimental Design: A total of 8,085 consecutive unselected Chinese breast cancer patients were enrolled. Germline mutations in 46 cancer susceptibility genes were detected using a 62-gene panel. Results: Pathogenic mutations were identified in 9.2% of patients among the 8,085 unselected breast cancer patients. Of these, 5.3% of patients carried a BRCA1 or BRCA2 mutation (1.8% in BRCA1 and 3.5% in BRCA2), 2.9% carried other breast cancer susceptibility genes (BOCG) and 1.0% carried another cancer susceptibility genes. Triple-negative breast cancers had the highest prevalence of BRCA1/2 mutations (11.2%) and other BOCG mutations (3.8%) among the four molecular subgroups, whereas ER−/PR−HER2+ breast cancers had the lowest mutations in BRCA1/2 (1.8%) and BOCG (1.6%). In addition, BRCA1 mutation carriers had a significant worse disease-free survival [unadjusted hazard ratio (HR) 1.60; 95% confidence interval (CI) 1.10–2.34; P = 0.014] and disease-specific survival (unadjusted HR 1.96; 95% CI, 1.03–3.65; P = 0.040) than did non-carriers, whereas no significant difference in survival was found between BRCA2 mutation carriers and non-carriers. Conclusions: 9.2% of breast cancer patients carry a pathogenic mutation in cancer susceptibility genes in this large unselected series. Triple-negative breast cancers have the highest prevalence of mutations in BRCA1 /2 and other breast cancer susceptibility genes among the four molecular subgroups, whereas ER−/PR−HER2+ breast cancers had the lowest mutations in these genes. Clin Cancer Res; 23(20); 6113–9. ©2017 AACR.

Association of SIPA1 545 C > T polymorphism with survival in Chinese women with metastatic breast cancer

It has been demonstrated that single nucleotide polymorphisms (SNPs) of SIPA1 (signal-induced proliferation associated gene 1) are associated with metastatic efficiency in both human and rodents. The purpose of this study was to determine whether SIPA1 545 C > T polymorphism was associated with overall survival in patients with metastatic breast cancer. In this study, SIPA1 545 C > T polymorphism was detected in 185 metastatic breast cancer patients using polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). Survival curves for patients with SIPA1 545 C > T polymorphism was compared using the Kaplan-Meier method with log-rank tests. We found that SIPA1 545 C > T polymorphism was significantly associated with survival in 185 patients with metastatic breast cancer. Patients with SIPA1 545 T/T genotype had a significantly worse overall survival (OS) than did patients with C/T or C/C genotype (50.0% vs. 62.9%, P = 0.042). Moreover, in multivariate analysis, as compared with the C/C or C/T genotype, the T/T genotype remained an independent unfavorable prognostic marker of OS in this cohort (hazard ratio [HR] = 2.16; 95% CI = 1.12–4.15; P = 0.022). Our findings indicate that metastatic breast cancer patients with SIPA1 545 T/T genotype have a poorer survival compared to patients with C/C or C/T genotype.

TP53 mutations are associated with higher rates of pathologic complete response to anthracycline/cyclophosphamide-based neoadjuvant chemotherapy in operable primary breast cancer.

The role of TP53 mutations in predicting response to neoadjuvant chemotherapy in breast cancer remains controversial. The aims of this study were to investigate whether TP53 mutations were associated with response and survival in breast cancer patients who received neoadjuvant chemotherapy. Therefore, we identified TP53 mutations in the core‐needle biopsy tumor samples obtained before the neoadjuvant chemotherapy from 351 operable primary breast cancer patients who either received anthracycline/cyclophosphamide‐based (n = 252) or paclitaxel (n = 99) neoadjuvant chemotherapy. We found that 41.0% (144 of 351) of patients harbored TP53 mutations, and 14.8% of patients achieved a pCR (pathologic complete response) after neoadjuvant chemotherapy. Among patients treated with anthracycline/cyclophosphamide (n = 252), patients with TP53 mutations had a significantly higher pCR rate than those with wild‐type (28.6 vs.7.1%; p < 0.001), and TP53 mutation was an independent favorable predictor of pCR [odds ratio (OR) = 3.41; 95% confidence interval (CI) 1.50–7.77; p = 0.003] in this group; moreover, patients with TP53 mutation had a better distant recurrence‐free survival (DRFS) than those with wild‐type [unadjusted hazard ratio (HR) = 0.43; 95% CI 0.20–0.94; p = 0.030] in this group. Among patients treated with paclitaxel (n = 99), no significant difference in pCR rates was observed between patients with or without TP53 mutations (15.2 vs. 11.3%; p = 0.57). Our results suggested that patients with TP53 mutations are more likely to respond to anthracycline/ cyclophosphamide‐based neoadjuvant chemotherapy and have a favorable survival.

Association of PIK3CA Mutation Status Before and After Neoadjuvant Chemotherapy with Response to Chemotherapy in Women with Breast Cancer

Purpose: The association between PIK3CA mutations and response to neoadjuvant chemotherapy in women with primary breast cancer is not fully elucidated. Experimental Design: PIK3CA mutations in breast cancer tissues that were taken prior to the initiation of neoadjuvant chemotherapy were identified in 729 operable primary breast cancer patients who received neoadjuvant chemotherapy. Among these, the PIK3CA mutations were also reassessed in tumor tissues procured following operation in 102 patients after completion of neoadjuvant chemotherapy. Results: A total of 206 out of 729 (28.3%) patients had PIK3CA mutations, and 19.5% of patients (142/729) in this cohort achieved a pathologic complete response (pCR) after neoadjuvant chemotherapy. Patients with PIK3CA mutations exhibited a lower pCR rate than did those with wild-type (14.6% vs. 21.4%, P = 0.035). No significant differences in disease-free survival (DFS) or distant disease-free survival (DDFS) were observed between PIK3CA mutant and wild-type in the entire study population. Among the 102 patients with PIK3CA mutation statuses available before and after neoadjuvant chemotherapy, 24 patients (23.5%) had PIK3CA mutations before neoadjuvant chemotherapy. Of these 24 patients, 15 patients retained their initial PIK3CA mutations and 9 patients lost their initial mutations after neoadjuvant chemotherapy. Patients who retained the initial mutations after neoadjuvant chemotherapy (n = 15) had a worse DDFS than the remaining patients (n = 87) in this subgroup [unadjusted HR, 2.34; 95% confidence interval (CI), 0.98–5.62; P = 0.050]. Conclusions: Patients with PIK3CA mutations are less likely to respond to neoadjuvant chemotherapy. Patients who retain their initial PIK3CA mutations after neoadjuvant chemotherapy have an unfavorable survival. Clin Cancer Res; 21(19); 4365–72. ©2015 AACR.

Somatic mutations in the BRCA1 gene in Chinese women with sporadic breast cancer

Recent studies suggested that breast cancer patients who carry a BRCA1 germline mutation benefit from poly (ADP-ribose) polymerase (PARP) inhibitors; therefore, it would be of great interest to detect BRCA1 somatic mutations in sporadic breast cancers. In this study, we detected BRCA1 somatic mutations in tumor cDNA from 144 Chinese women with sporadic breast cancer by using polymerase chain reaction (PCR)-direct sequencing assay. In total, eight BRCA1 alterations (three nonsense mutations and five missense mutations) were identified in this cohort of 144 sporadic breast cancers. We further confirmed that 5 out of 144(3.5%) sporadic breast cancer cases carried a BRCA1 somatic mutation, including two novel nonsense mutations (c.191_212del22 and c.2963C>G) resulting in a truncated protein and three missense mutations (c.114G>T, c.925A>C, and c.824G>A). The two cases with BRCA1 somatic truncating mutations also contained a TP53 somatic mutation in the tumors. Our study suggested that a small subset of sporadic breast cancers do harbor BRCA1 somatic mutations; these patients who carry a BRCA1 somatic mutation may be potential candidates for treatment with PARP inhibitors.