Survinin expression in patients with breast cancer during chemotherapy

Identification of prognostic significance of BIRC5 in breast cancer using integrative bioinformatics analysis

Aims: Baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5) plays vital roles in carcinogenesis by influencing cell division and proliferation and by inhibiting apoptosis. However, the prognostic significance of BIRC5 remains unclear in breast cancer.

Methods:BIRC5 expression and methylation status were evaluated using the Oncomine and The Cancer Genome Atlas (TCGA) databases. The relevance between BIRC5 and different clinicopathological features as well as survival information was analyzed using the bc-GenExMiner database and Kaplan–Meier Plotter. BIRC5–drug interaction network was obtained using the Comparative Toxicogenomics Database.

Results: Based on the results from databases and own hospital data, BIRC5 was higher expressed in different breast cancer subtypes compared with the matched normal individuals. Hormone receptors were negatively correlated with BIRC5 expression, whereas the Scarff–Bloom–Richardson (SBR) grade, Nottingham Prognostic Index (NPI), human epidermal growth factor receptor-2 (HER-2) status, basal-like status, and triple-negative status were positively related to BIRC5 level in breast cancer samples with respect to normal tissues. High BIRC5 expression was responsible for shorter relapse-free survival, worse overall survival, reduced distant metastasis free survival, and increased risk of metastatic relapse event. BIRC5–drug interaction network indicated that several common drugs could modulate BIRC5 expression. Furthermore, a positive correlation between BIRC5 andcell-division cycle protein 20 (CDC20) gene was confirmed.

Conclusion:BIRC5 may be adopted as a promising predictive marker and potential therapeutic target in breast cancer. Further large-scale studies are needed to more precisely confirm the value of BIRC5 in treatment of breast cancer.

BIRC5/Survivin Expression as a Non-Invasive Biomarker of Endometriosis

The etiology of endometriosis is highly complex, and although it is a benign disease, it has several biological behaviors similar to malignant lesions, including cell invasion, neo-angiogenesis, and decreased apoptosis. Survivin is a protein encoded by the BIRC5 gene that plays a role in cell division by inhibiting apoptosis and regulating the process of mitosis in embryonic and cancer cells. Therefore, we aimed to evaluate the expression of BIRC5 in samples of peripheral blood of women with and without endometriosis. This study comprised of 40 women with endometriosis and 10 healthy women as controls. Peripheral blood samples were collected in the three phases of the menstrual cycle (follicular, ovulatory, and luteal). The expression of the BIRC5 gene was evaluated by RT-qPCR using the TaqMan methodology. The BIRC5 expression was significantly higher in all phases of the menstrual cycle in women with endometriosis, regardless of the disease stage. The accuracy of BIRC5 expression in the peripheral blood for the diagnosis endometriosis presented AUC of 0.887 (p < 0.001), with 97.2% of sensitivity and specificity of 65.5% considering the overall endometriosis group. Regarding the minimal/mild endometriosis group, the AUC presented a value of 0.925 (p < 0.001), with 100% of sensitivity and 79.3% of specificity, whereas in the moderate/severe endometriosis group the AUC was 0.868 (p < 0.001), with a sensitivity of 95.8% and specificity of 65.5%. These findings suggest that the expression of BIRC5 may be a potential noninvasive biomarker for the diagnosis of endometriosis.

The role of survivin in the pathogenesis of endometriosis

INTRODUCTION

Endometriosis is a common, estrogen-dependent condition, defined as the presence of endometrial-like tissue outside of the uterus, associated with often chronic and inflammatory reaction. The association of endometriosis with cancer is unclear, although endometriosis and cancer present some molecular similarities. Survinin, encoded by the BIRC5 gene, is a protein that controls cell division, inhibits apoptosis and promotes angiogenesis. Here we aimed to summarize and to discuss the main findings of studies that addressed the involvement of survivin in the pathogenesis of endometriosis.

EVIDENCE ACQUISITION

We conducted a comprehensive retrieval from electronic databases, included the MEDLINE, EMBASE, with no restrictions to time span. We used the search terms endometriosis and survivin or BIRC5 and collected all relevant studies to explore the association between endometriosis and surviving expression.

EVIDENCE SYNTHESIS

A total of 21 studies included in the systematic review, comprising sample collected from 1263 women with endometriosis. Results showed the involvement of more than 60 genes and proteins evaluated in eutopic, ectopic, endometrial and ovarian endometriosis, as well as in several gynecological conditions compared to healthy controls.

CONCLUSIONS

The studies provided the basis for the involvement of survivin in the pathogenesis of the disease by several and independent pathways.

Polymorphisms in Survivin (BIRC5 Gene) Are Associated with Age of Onset in Breast Cancer Patients

Survivin, encoded by BIRC5 gene (baculoviral IAP repeat containing 5), belongs to the family of inhibitors of apoptosis proteins (IAPs). In mammalian cells it participates in the control of mitosis, apoptosis regulation, and cellular stress response. Its expression is increased in almost all types of cancers. The aim of this study was to investigate the role of BIRC5 polymorphisms in breast cancer (BC) and to connect survivin expression with various clinicopathological characteristics of BC patients. Blood and archival tumour tissue samples were collected from 26 BC patients from Croatia. Survivin expression was determined immunohistochemically. BIRC5 promoter, coding region, and 3'UTR were genotyped. DNA from 74 healthy women was used as control. BIRC5 polymorphisms and survivin expression were tested against age of onset, histological grade, tumour type and size, lymph node status, oestrogen, progesterone, Her2, and Ki67 status. Numbers of samples with weak, moderate, and strong survivin expression were 9 (33.3%), 11 (40.7%), and 7 (25.9%), respectively. Most patients had nuclear survivin staining (92.6%). High survivin expression was significantly associated with negative oestrogen receptor status (p=0.007) and positive Ki67 expression (p=0.032). Ki67 expression was also positively correlated with histological grade (p=0.0009). Fourteen polymorphisms were found in BC samples, located mostly in promoter and 3'UTR of BIRC5. There was no significant difference in the distribution of polymorphisms between BC and control samples. Among clinicopathological characteristics of BC patients, alleles of five BIRC5 polymorphisms were associated with younger age of onset: c.-644T>C (55.8 years [y] vs. 48.1 y; p=0.006), c.-241C>T (54.2 y vs. 45.0; p=0.029), c.9809T>C (55.8 y vs. 48.1 y; p=0.006), c.-1547C>T (58.3 y vs. 50.9 y; p=0.011), and c.9386T>C (50.8 y vs. 59.5 y; p=0.004). To assess the significance of BIRC5 polymorphisms and survivin expression as predictive and prognostic biomarkers for BC further research with a larger sample size is needed.

The landscape of chromosomal aberrations in breast cancer mouse models reveals driver-specific routes to tumorigenesis

Aneuploidy and copy-number alterations (CNAs) are a hallmark of human cancer. Although genetically engineered mouse models (GEMMs) are commonly used to model human cancer, their chromosomal landscapes remain underexplored. Here we use gene expression profiles to infer CNAs in 3,108 samples from 45 mouse models, providing the first comprehensive catalogue of chromosomal aberrations in cancer GEMMs. Mining this resource, we find that most chromosomal aberrations accumulate late during breast tumorigenesis, and observe marked differences in CNA prevalence between mouse mammary tumours initiated with distinct drivers. Some aberrations are recurrent and unique to specific GEMMs, suggesting distinct driver-dependent routes to tumorigenesis. Synteny-based comparison of mouse and human tumours narrows critical regions in CNAs, thereby identifying candidate driver genes. We experimentally validate that loss of Stratifin (SFN) promotes HER2-induced tumorigenesis in human cells. These results demonstrate the power of GEMM CNA analysis to inform the pathogenesis of human cancer.

Genetically engineered mouse models of cancer are useful in identifying oncogenes and tumour suppressors. Here, the authors use gene expression profiles to generate a catalogue of copy number aberrations in 45 mouse models, and compare mouse and human tumours to identify additional drivers of tumorigenesis.