Yifeng Hou

Identification of a comprehensive spectrum of genetic factors for hereditary breast cancer in a Chinese population by next-generation sequencing

The genetic etiology of hereditary breast cancer has not been fully elucidated. Although germline mutations of high-penetrance genes such as BRCA1/2 are implicated in development of hereditary breast cancers, at least half of all breast cancer families are not linked to these genes. To identify a comprehensive spectrum of genetic factors for hereditary breast cancer in a Chinese population, we performed an analysis of germline mutations in 2,165 coding exons of 152 genes associated with hereditary cancer using next-generation sequencing (NGS) in 99 breast cancer patients from families of cancer patients regardless of cancer types. Forty-two deleterious germline mutations were identified in 21 genes of 34 patients, including 18 (18.2%) BRCA1 or BRCA2 mutations, 3 (3%) TP53 mutations, 5 (5.1%) DNA mismatch repair gene mutations, 1 (1%) CDH1 mutation, 6 (6.1%) Fanconi anemia pathway gene mutations, and 9 (9.1%) mutations in other genes. Of seven patients who carried mutations in more than one gene, 4 were BRCA1/2 mutation carriers, and their average onset age was much younger than patients with only BRCA1/2 mutations. Almost all identified high-penetrance gene mutations in those families fulfill the typical phenotypes of hereditary cancer syndromes listed in the National Comprehensive Cancer Network (NCCN) guidelines, except two TP53 and three mismatch repair gene mutations. Furthermore, functional studies of MSH3 germline mutations confirmed the association between MSH3 mutation and tumorigenesis, and segregation analysis suggested antagonism between BRCA1 and MSH3. We also identified a lot of low-penetrance gene mutations. Although the clinical significance of those newly identified low-penetrance gene mutations has not been fully appreciated yet, these new findings do provide valuable epidemiological information for the future studies. Together, these findings highlight the importance of genetic testing based on NCCN guidelines and a multi-gene analysis using NGS may be a supplement to traditional genetic counseling.

Positive expression of miR-361-5p indicates better prognosis for breast cancer patients

BACKGROUND MicroRNA-361-5p (miR-361-5p) has been reported to be tumor suppressor in colorectal, gastric and prostate cancer, but as an oncogene in cervical cancer. No previous research has focused on the expression of miR-361-5p and its exact prognostic role in breast cancer (BC). METHODS In this study, a tissue microarray (TMA)-based miRNA detection in situ hybridization (ISH) with LNA probe was used to detect miR-361-5p expression in 375 BC tissue. The expression level of miR-361-5p in BC and its potential prognostic value was investigated. RESULTS Positive miR-361-5p staining was observed in 78.7% (N=295; 78.7% positive, 21.3% negative) in the 375 cases. The clinical outcome of patients with positive miR-361-5p expression [median disease-free survival (DFS) time 95.52 months] was significantly better than that of patients (median DFS time 82.33 months) with negative miR-361-5p expression (P=0.002). Moreover, the prognostic value of miR-361-5p was most significant among patients with triple-negative breast cancer (TNBC) for DFS (P=0.004). CONCLUSIONS These results indicated that miR-361-5p expression is an independent predictive factor for better prognosis in BC.

Abstract P1-12-02: Effect of using LHRH analog during chemotherapy (CT) on premature ovarian failure and prognosis in premenopausal patients with early-stage, hormone receptor-positive breast cancer: The primary analysis of a randomized controlled phase III trial

Background: Whether administration of LHRH analog during CT in premenopausal patients with early-stage, hormone receptor-positive disease would reduce CT-induced premature ovarian failure (POF) is still controversial. Moreover, whether LHRH analog would influence the prognosis of patients is unknown yet. This randomized study is to evaluate whether administration of LHRH analog during CT would reduce POF and effect the prognosis of breast cancer. Methods: This is arandomized, controlled phase III clinical trial. Premenopausal patients age Results: Between 2/09 and 5/13, the trial has finished enrollment, 216 patients were enrolled. The median age were 37.5 in combined arm (n=108) and 39 in sequential arm (n=108), respectively. The median follow-up time was 27.4 months and 25.7 months, respectively. 15 patients and 21 patients received neoadjuvant CT, respectively. There were no significant difference in age, tumor stage and CT regimens (p>.05). The median cycles of GN were 25, respectively. 47% had complete primary endpoint data. POF rate were 5/42 (11.9%) in the combined arm and 16/60 (26.7%) in the sequential arm. POF rate (and post-menopausal FSH) rate were 1/42 (2.4%) in the combined arm and 8/60 (13.3%) in the sequential arm. In neoadjuvant CT subgroup, each has 1 patient achieved pathological complete remission, and there was no significant difference in objective clinical response. There were 9 patients in the combined arm and 3 patients in the sequential arm had occured RFS events (including 2 and 0 deaths, respectively, OR=3.18, 95%CI:0.84-12.09, P=.075). Conclusions:LHRH analog administration with CT might be associated with less POF and did not affect the efficacy of neoadjuvant CT, however, had no RFS benefit, it may need longer follow-up. We will conduct an interim analysis in November 2014. Clinicaltrials.gov Registry Number: NCT01712893. Citation Format: Jian-Wei Li, Guang-yu Liu, Ke-Da Yu, Ya-jie Ji, Miao Mo, Li Lei, Jiong Wu, Gen-hong Di, Yi-feng Hou, Zhen Hu, Can-ming Chen, Zhen-Zhou Shen, Zhi-Ming Shao. Effect of using LHRH analog during chemotherapy (CT) on premature ovarian failure and prognosis in premenopausal patients with early-stage, hormone receptor-positive breast cancer: The primary analysis of a randomized controlled phase III trial [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P1-12-02.

Quality of Life and Psychological State in Chinese Breast Cancer Patients Who Received BRCA1/2 Genetic Testing.

Background This study aims to understand the quality of life (QOL) and psychological state (PS) of Chinese breast cancer patients who received BRCA1/2 genetic testing; to examine the psychological changes between BRCA1/2 mutation carriers and non-carriers; and to further explore the psychological experience of BRCA1/2 mutation carriers. Methods This study was combined with quantitative and qualitative designs. First, we performed a quantitative investigation using FACT-B (Chinese version) and Irritability, Depression and Anxiety scale (IDA) to assess the QOL and PS in breast cancer patients who received BRCA1/2 genetic testing. Then semi-structured in-depth qualitative interviews among 13 mutation carriers were conducted in hospital. Results Results from the quantitative study showed QOL scores were relatively high and the IDA scores were relatively low among the patients, and there was no significant difference in the QOL or IDA scores between non-carriers and carriers. Based on the qualitative analysis, four main themes emerged: (1) Finding the reason for having breast cancer; (2) Negative emotions; (3) Behavioral changes; (4) Lack of information. Conclusions The present study showed that QOL and PS are good among the breast cancer patients who received genetic testing. Genetic testing itself does not cause long psychosocial effects. BRCA1/2 mutation carriers may have certain negative emotions at the first stage they knew the testing results and may initiate behavioral and lifestyle changes. The patients with a BRCA1/2 mutation desire knowledge with regard to genetic aspects in mainland China. Professional information and advice can be provided to relieve the patients’ negative emotions when they were informed of gene defect.

Germline mutations of TP53 gene among Chinese families with high risk for breast cancer

OBJECTIVE To evaluate the role of germline mutations of TP53 gene among a Chinese population with high risk for breast cancer. METHODS A total of 81 BRCA-negative breast cancer probands from cancer families were analyzed using targeted capture and next-generation sequencing. Candidate mutations were verified with Sanger sequencing. Co-segregation analyses were carried out to explore the likely pathogenicity of the mutation. RESULTS Of the 81 BRCA-negative patients, 3 exonic mutations in the TP53 gene were identified in 3 breast cancer patients. Of these, 2 mutations were previously reported and 1 was novel. One family with TP53 mutation has met the criteria for Li-Fraumeni syndrome (LFS) and accounted for 9.1% of all families who fulfilled the diagnostic criteria for LFS. Two of the carriers were diagnosed with breast cancer under the age of 30, and have accounted for 11.8% (2/17) of all very young (≤30 years) breast cancer patients in our study. CONCLUSION The TP53 germline mutation is more common in Chinese population with a high risk for breast cancer than previously thought. TP53 gene mutation screening should be considered particularly for patients with a family history of LFS and very young age of onset.

Correction to: Identification of the functional role of peroxiredoxin 6 in the progression of breast cancer

After the publication of this work [1] an error in Fig. 1c was brought to our attention: the Western blots for PRDX6 and β-actin were similar to those shown in lanes 5-6 of Fig. 4g. To verify these findings, we have repeated this experiment and the results are shown in a new Fig. 1c below. The repeated experimental results are consistent with the previously reported findings in the original study [1] and the functional role for PRDX6 in malignant progression of human cancer including breast cancer has been widely documented and recognized in numerous other studies [2]. We apologize for the error. However, this correction does not affect the conclusions of the article.

P3-17-08: Macroautophagy Protects Breast Cancer MCF-7 Cells from TAM-Induced Apoptosis Via Mitogen-Activated Protein Kinase (MAPK) Pathway.

Tamoxifen (TAM) has been used ubiquitously for endocrine therapy for the hormone-sensitive breast cancer. Several studies have revealed that tamoxifen treatment induced apoptosis and at the same time tamoxifen increased autophagic levels in MCF-7 cells. The previous studies attempt to elaborate the significance and mechanism of autophagy induced by TAM in breast cancer cells, however, there are contradictions among their conclusions, it is still not clear that autophagy protects MCF-7 from apoptosis or promotes apoptosis. Better understanding of the effect of autophagy induced by TAM in breast cancer cells on apoptosis will be of the important clinical significance in endocrine therapy for breast cancer. The present study shows that tamoxifen treatment significantly increased autophagic levels by inducing autophagic vacuoles formation in MCF-7 cells observed by means of transmission electron microscopy and enhancing the expression of autophagy marker, icrotubule-associated protein light chain 3 measured by Western blot. Our research shows tamoxifen enhanced the phosphorylation of MAPKs when inducing autophagy and autophagy decreased significantly when kinase inhibitors were separately used to inhibit the phosphorylation of ERK, JNK, p38 MAPK. MAPK signal transduction pathway was involved in the process of autophagy in MCF-7 cells. To investigate whether Estrogen receptor-α participated in autophagy caused by tamoxifen, we constructed Estrogen receptor-α gene ESR/1 shRNA expression vector and it could effectively inhibit the expression of ER-α in MCF-7 cells. Our research shows that autophagy was decreased with the downregulation of ER-α, so we conclude that Estrogen receptor-a also involved in autophagy induced by tamoxifen in MCF-7 cells. To find out the specifical role of autophagy in tamoxifen treated breast cancer cell MCF-7, we inhibited autophagy producing after tamoxifen treatment by pretreating the cells with chloroquine and 3-methyladenine, both commonly used as autophagy inhibitors. Another method for autophagy inhibition was Becline-1 siRNA transfection into MCF-7 cells. Than we stained MCF-7 cells with anti-Annexin V FITC and PI and examinated apoptotic rate by flow cytometer and we also detected activity of caspase7 in MCF-7 cells. The results indicate that inhibition of autophagy by the methods mentioned induced higher apoptotic level, therefore, autophagy protected MCF-7 from apoptosis and inhibiting autophagy may be a new strategy to augment the theraputic effect of tamoxifen treatment. In our study, we induced breast cancer cell MCF-7 resistant to TAM in vitro and we found much higher autophagic level in TAM resisitant cells compared with TAM not resisitant MCF-7 cells. We draw the conclusion that inhibition of autophagy induced by tamoxifen may be a new therapy for tamoxifen resisitant breast cancer. Key words : tamoxifen, breast cancer, autophagy, MCF-7 cells, MAPKs, estrogen receptor, inhibition, apoptosis Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-17-08.