Palbociclib sensitizes ER-positive breast cancer cells to fulvestrant by promoting the ubiquitin-mediated degradation of ER-α via SNHG17/Hippo-YAP axis.

PURPOSE: Endocrine therapy is the anti-tumor therapy for human breast cancer but endocrine resistance was a major burden. It has been reported that Palbociclib and fulvestrant can be used in combination for the treatment of patients who are experiencing endocrine resistance. However, the underlying mechanism is unclear. In this study, we aimed to investigate the mechanism by which Palbocicilib affected ER-positive breast cancer, combined with fulvestrant. METHODS: We first detected the effect of palbociclib on cell survival, growth and cycle distribution separately by MTT, colony formation and flow cytometry. Then SNHG17 was screened as palbociclib-targeted LncRNA by LncRNA-seq, and the SNHG17-targeted mRNAs were selected by mRNA-seq for further determination. Subsequently, the underlying mechanism by which palbociclib promoted the cytotoxicity of fulvestrant was confirmed by qRT-PCR, western blot, and immunoprecipitation. Eventually, the xenograft model and immunohistochemistry experiments were used to validate the sensitization effect of palbociclib on fulvestrant and its mechanism in vivo. RESULTS: Palbociclib significantly enhanced the cytotoxicity of fulvestrant in fulvestrant-resistant breast cancer cell lines. Interestingly, this might be related to the lncRNA SNHG17 and the Hippo signaling pathway. And our subsequent western blotting experiments confirmed that overexpressing SNHG17 induced the down-regulation of LATS1 and up-regulated YAP expression. Furthermore, we found that the increased sensitivity of breast cancer cells was closely associated with the LATS1-mediated degradation of ER-α. The following animal experiments also indicated that overexpressing SNHG17 obviously impaired the anti-cancer effect of co-treatment of palbociclib and fulvestrant accompanied by decreased LATS1 and increased ER-α levels. CONCLUSION: Palbociclib might sensitize the cytotoxicity of fulvestrant in ER-positive breast cancer cells by down-regulating SNHG17 expression, and then resulted in the LATS1-inactivated oncogene YAP and LATS1-mediated degradation of ER-α.

Drug-resistant HER2-positive breast cancer: Molecular mechanisms and overcoming strategies.

Breast cancer is one of the most common malignancies and the leading cause of cancer-related death in women. HER2 overexpression is a factor for poor prognosis in breast cancer, and anti-HER2 therapy improves survival in these patients. A dual-targeted combination of pertuzumab and trastuzumab, alongside cytotoxic chemotherapy, constitutes the primary treatment option for individuals with early-stage, HER2-positive breast cancer. Antibody-drug conjugate (ADC) and tyrosine kinase inhibitors (TKI) also increase the prognosis for patients with metastatic breast cancer. However, resistance to targeted therapy eventually occurs. Therefore, it is critical to investigate how HER2-positive breast cancer is resistant to targeted therapy and to develop novel drugs or strategies to overcome the resistance simultaneously. This review aims to provide a comprehensive discussion of the HER2-targeted agents currently in clinical practice, the molecular mechanisms of resistance to these drugs, and the potential strategies for overcoming resistance.

Curcuma zedoaria petroleum ether extract reverses the resistance of triple-negative breast cancer to docetaxel via pregnane X receptor.

BACKGROUND: Triple-negative breast cancer (TNBC) is characterized by its aggressiveness and poor prognosis. Docetaxel is the common chemotherapeutic drug used in the treatment of TNBC. However, resistance to docetaxel has limited the effectiveness of TNBC treatment. Petroleum ether extracts of Curcuma zedoaria (PECZ) can inhibit the proliferation of MDA-MB-231 cells. However, the effect of PECZ on docetaxel resistance is not clear. METHODS: A docetaxel-resistant MDA-MB-231 (MDA-MB-231/docetaxel) cell line was established, and Cell Counting Kit-8 (CCK-8), quantitative real-time PCR (qRT-PCR), and western blotting assays were used to evaluate the effect of docetaxel resistance in MDA-MB-231 cells. Next, CCK-8 was also performed to detect the effect of docetaxel or the combination treatment of docetaxel and PECZ on the proliferation of MDA-MB-231/docetaxel cells. Thereafter, MDA-MB-231/docetaxel cells were subcutaneously injected into nude mice to induce a TNBC xenograft model, and the mice were divided into a model group, docetaxel group, PECZ group, and combination of docetaxel and PECZ group. Subsequently, hematoxylin and eosin (HE) staining, immunohistochemical, qRT-PCR, and western blotting were used to estimate the effect of pre-treatment with PECZ on docetaxel tolerance reversal. RESULTS: PECZ significantly inhibited the expression of pregnane X receptor (PXR), multidrug resistance 1 (MDR1), breast cancer resistance protein (BCRP), and cytochrome P-450 (CYP3A4) in MDA-MB-231/docetaxel cells. Only higher concentrations of docetaxel could inhibit the viability of MDA-MB-231/docetaxel cells. When pre-treated with PECZ, lower concentrations of docetaxel could significantly inhibit cell viability. Meanwhile, combination treatment also reduced the tumor volume, ameliorated the pathological change of tumor tissues, and down-regulated the expressions of PXR, MDR1, BCRP, and CYP3A4 (according to HE staining, immunohistochemical, qRT-PCR and western blotting results in vivo). CONCLUSIONS: Our research showed that PECZ reversed docetaxel resistance in TNBC by PXR both in vitro and in vivo, which provides the basis for further investigations into the potential therapeutic impact of docetaxel resistance in TNBC.

Preoperative Systemic Therapy Versus Upfront Surgery in HER2-Positive Breast Cancer in the Real World.

PURPOSE: To compare survival in different strategies, preoperative systemic treatment versus upfront surgery, in HER2-positive early breast cancer patients in the real world. METHODS: According to the actual upfront treatment, eligible patients from 2012 to 2015 were classified as preoperative systemic treatment or upfront surgery group prospectively. The primary endpoint is disease-free survival; the second endpoint is overall survival. All the outcomes were examined in the propensity score matching model and inverse probability of treatment weighting model. RESULTS: Included in the analysis were 1,067 patients (215 in the preoperative systemic treatment group, 852 in the upfront surgery group). In the propensity score matching model (matching at 1:1 ratio), the disease-free survival of the preoperative systemic treatment group was significantly higher than that of the upfront surgery group (hazard ratio, 0.572, 95%CI, 0.371-0.881, P, 0.012). In the inverse probability of treatment weighting model, there was no significant difference in disease-free survival between the two groups (hazard ratio, 0.946, 95%CI, 0.763-1.172, P, 0.609). For overall survival, there was no significant difference between the two groups. CONCLUSION: The HER2-positive patients who accepted preoperative systemic treatment had better disease-free survival than those who underwent upfront surgery by real-world statistic methods. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, identifier NCT04249440.

Impact on survival of estrogen receptor, progesterone receptor and Ki-67 expression discordance pre- and post-neoadjuvant chemotherapy in breast cancer.

PURPOSE: To investigate whether estrogen receptor (ER), progesterone receptor (PR) and Ki-67 expression discordance before and after neoadjuvant chemotherapy (NAC) correlates with prognosis and treatment of breast cancer patients. METHODS: The study cohort included 482 breast cancer patients at the Zhejiang Cancer Hospital from January 1, 2008, to December 31, 2018. Core needle biopsies and excised tissue biopsies pre- and post-NAC were obtained. Immunohistochemistry was used to determine ER, PR and Ki-67 status. The relationship between biomarker discordance before and after NAC and clinicopathological features was compared retrospectively. RESULTS: ER (n = 482), PR (n = 482) and Ki-67 (n = 448) expression was assessed in the same lesion pre- and post-NAC. Discordance in the three markers pre- and post-NAC was observed in 50 (10.4%), 82 (17.0%) and 373 (77.4%) cases, respectively. Positive-to-negative PR expression changes were the most common type of discordance observed. The risk of death in patients with a PR positive-to-negative conversion was 6.58 times greater than for patients with stable PR expression. The risk of death in patients with increased Ki-67 expression following NAC treatment was 2.05 times greater than for patients with stable Ki-67 expression. CONCLUSION: Breast cancer patients showed changes in ER, PR and/or Ki-67 status throughout NAC, and these changes possibly influenced disease-free survival and overall survival. A switch to negative hormone receptor expression with increased Ki-67 expression following NAC could be indicators of a worse prognosis. Biomarker expression investigations following NAC may potentially improve patient management and survival.

A Prospective Validation Cohort Study of a Prediction Model on Non-sentinel Lymph Node Involvement in Early Breast Cancer.

BACKGROUND: Early breast cancer with one or two sentinel lymph nodes (SLNs) may omit axillary lymph node dissection (ALND) if followed by radiotherapy. However, only less than one-third of the patients have positive non-SLNs and can truly benefit from radiotherapy. Before any regional treatment decision, the risk of non-SLN metastasis must be identified. The authors previously developed a predictive model for non-SLN involvement using CK19 mRNA and contrast-enhanced ultrasound (CEUS) score in a training set. They designed a further study to evaluate the predictive effect using the model prospectively in a validation set of one or two involved SLNs. METHODS: This study identified early breast cancer patients at Zhejiang Cancer Hospital from July 2017 to June 2018. The CK19 mRNA tested by quantitative real-time polymerase chain reaction and CEUS scores were collected before surgery. Patients with one or two involved SLNs were enrolled and underwent ALND. The estimated percentage of non-SLN involvement was calculated by the authors' model formula and the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram. The false-negative rates, predictive accuracy, and area under curve (AUC) were compared between two predictive models. RESULTS: The study enrolled 235 patients, and 35.36% (83/235) of them had non-SLN involvement. The authors' model had a false-negative rate of 6% and an accuracy of 94.9%. The AUC was 0.952 (95% confidence interval [CI] 0.922-0.982), which was significantly higher than that of the MSKCC model at all three cutoff value levels. CONCLUSION: The authors' model, using CK19 mRNA and the CEUS score, showed the potential predictive value of non-SLNs before surgery for early breast cancer patients. CLINICALTRIALS REGISTRY: NCT02992067, NCT03280134.

Prognosis and endocrine therapy selection for patients with low hormone receptor-positive breast cancer following neoadjuvant chemotherapy: A retrospective study of 570 patients in China.

The 2010 American Society of Clinical Oncology guidelines have reduced the immunohistochemistry cut-off value for determining estrogen receptor b positivity from 10 to 1% of stained cells in breast cancer. In clinical practice, low-hormone receptor positive (low HR+) tumors are classified in the luminal subtype, although they exhibit aggressive features and poor prognosis. Information regarding the prognosis of patients with breast cancer following treatment with optimal endocrine therapy and neoadjuvant chemotherapy (NAC) is currently lacking. In the present study, the differences in clinical characteristics and survival of patients with breast cancer were compared among those with low and high HR+ breast cancer who received NAC. Furthermore, the effects of different types of endocrine therapies on the prognosis of patients with breast cancer were compared. The study population comprised patients with primary breast cancer who were treated at the Zhejiang Cancer Hospital between January, 2007 and December, 2017. Patients were divided into three groups based on the results of immunohistochemistry: HR+ (positive staining >10%), HR- (positive staining <1%) and low HR+ (positive staining 1-10%). The low HR+ group was further divided into three subgroups according to the different endocrine therapies administered: Tamoxifen, aromatase inhibitor or no treatment. Among the 570 patients included in the present study, 60 (10.53%) patients had low HR+ tumors. With a median follow-up of 48.98 months, patients with low HR+ tumors had reduced survival rates compared with those with HR+ tumors. Furthermore, the pathologic complete response rate (pCR) of patients with low HR+ was comprised between pCR from patients with HR+ and pCR from patients with HR- following NAC treatment. In addition, no significant difference in the overall prognosis was observed among patients with low HR+ following treatment with different endocrine therapies. Subsequently, patients in the low HR+ group were more likely to benefit from NAC compared with patients in the HR+ group. Intensive endocrine therapy may therefore improve the prognosis of patients with breast cancer and low HR+; however, further investigation is required.

Effect of cimicifuga racemosa on menopausal syndrome caused by LHRH-a in breast cancer.

ETHNOPHARMACOLOGICAL RELEVANCE: Cimicifuga racemose is previously proved effective on nature menopausal syndrome (MPS). However, its clinical value in treating with MPS induced by luteinizing-hormone releasing hormone analogue (LHRH-a) therapy of pre-/peri-menopausal breast cancer patients is still unknown. AIM OF STUDY: This perspective randomised-design study is to investigate the effect and safety of cimicifuga racemosa on MPS induced by LHRH-a in breast cancer (clinical trial registered: NCT03339882). MATERIALS AND METHODS: Breast cancer patients planning for LHRH-a treatment were randomly divided into 2 groups. The control group which was being treated with the standard treatment of LHRH-a. The other group was being treated with Remifemin, the commercialized product of cimicifuga racemose extract, combined with LHRH-a, called Remifemin group. Our main endpoint was Kupperman menopause index (KMI). Hormone levels in peripheral blood and gynecological complications were also evaluated. RESULTS: Totally, 85 patients (42 in Remifemin group and 43 in control group) were enrolled in Zhejiang Cancer Hospital. At the 4th, 8th and 12th week after using LHRH-a, the KMI were all significantly lower in Remifemin group than in control group (P < 0.01), while the hormone levels, including estradiol (E2), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were similar in the two groups. In addition, the incidence of cervical cyst in Remifemin group was higher than that in control group (P = 0.02), and there was no significant difference in the other gynecological complications, including endometrial thickening, ovarian cyst or uterine fibroid (P > 0.05). CONCLUSIONS: Cimicifuga racemose is effective, oncological safe and reliable for treatment of MPS caused by LHRH-a in breast cancer.

Long noncoding RNA TALNEC2 plays an oncogenic role in breast cancer by binding to EZH2 to target p57KIP2 and involving in p-p38 MAPK and NF-κB pathways.

We aimed to investigate the potential role and regulatory mechanism of long noncoding RNA tumor-associated lncRNA expressed in chromosome 2 (TALNEC2) in breast cancer. The expression of TALNEC2 in breast cancer tissues and cells were investigated. MCF-7 and MDA-MB-231 cells were transfected with small interfering RNA (siRNA) duplexes for targeting TALNEC2 (si-TALNEC2), enhancer of zeste homolog 2 (EZH2; si-EZH2) and p57KIP2 (si-p57 KIP2 ), and their corresponding controls (si-NC). The viability, colony forming ability, cell cycle, apoptosis, and autophagy of transfected cells were assessed. The expressions of p-p38 mitogen-activated protein kinase (MAPK) and nuclear factor κB (NF-κB) pathway-related proteins were investigated. The results showed that TALNEC2 was highly expressed in breast cancer tissues and cells. Knockdown of TALNEC2 significantly inhibited the malignant behaviors of MCF-7 and MDA-MB-231 cells, including inhibiting cell viability and colony forming, arresting cell cycle at G0/G1 phase, inducing cell apoptosis, and promoting cell autophagy. EZH2 was a TALNEC2 binding protein, which was upregulated in breast cancer tissues and cells and could negatively regulate p57 KIP2 . Effects of TALNEC2 knockdown on malignant behaviors of MCF-7 cells were reversed by p57 KIP2 knockdown. The expressions of p-p38, RelA, and RelB in MCF-7 cells were decreased after knockdown of TALNEC2 or EZH2, which were reversed by knockdown of p57 KIP2 concurrently. In conclusion, TALNEC2 may play an oncogenic role in breast cancer by binding to EZH2 to target p57 KIP2 . Activation of p-p38 MAPK and NF-κB pathways may be key mechanisms mediating the oncogenic role of TALNEC2 in breast cancer. TALNEC2 may serve as a promising target in the therapy of breast cancer.

The Dysregulated Expression of KCNQ1OT1 and Its Interaction with Downstream Factors miR-145/CCNE2 in Breast Cancer Cells.

BACKGROUND/AIMS: Next-generation sequencing (NGS) has revealed abundant long noncoding RNAs (lncRNAs) that have been characterized as critical components of cancer biology in humans. The present study aims to investigate the role of the lncRNA KCNQ1OT1 in breast cancer (BRCA) as well as the underlying molecular mechanisms and functions of KCNQ1OT1 involved in the progression of BRCA. METHODS: The Cancer Genome Atlas (TCGA) and StarBase v2.0 were used to obtain the required gene data. Dual luciferase reporter gene assays were conducted to verify the relevant intermolecular target relationships. QRT-PCR and Western blot were performed to measure the expression levels of different molecules. Cell proliferation was detected by using the MTT and colony formation assays, while cell migration and invasion were examined by transwell assay. Variations in cell apoptosis and cell cycle were determined through flow cytometry. A tumor xenograft model was applied to assess tumor growth in vivo. RESULTS: KCNQ1OT1 was found to be remarkably highly expressed in BRCA tissues and cells. KCNQ1OT1 modulated CCNE2 through sponging miR-145 in BRCA. KCNQ1OT1 promoted tumor growth in vivo by regulating miR-145/CCNE2. CONCLUSION: The KCNQ1OT1/miR-145/CCNE2 axis plays a critical regulatory role in BRCA, potentially giving rise to BRCA tumorigenesis and progression. These findings provide valuable evidence for improving the diagnosis and treatment of BRCA in the future.

Knockdown of ribosomal protein S15A inhibits proliferation of breast cancer cells through induction of apoptosis in vitro.

To explore the role of ribosomal protein S15A (RPS15A) in breast cancer. The Oncomine database was used to compare the expression of RPS15A in human breast cancer tissues and normal tissues. RPS15A in breast cancer cell line ZR-75-30 and BT474 was specifically knocked down using lentivirus-mediated short hairpin RNAs (shRNAs). RPS15A knockdown efficiency was validated by quantitative polymerase chain reaction and western blot analysis. Subsequently, the functional effects of RPS15A on proliferation of breast cancer cells were investigated by MTT, colony formation and flow cytometry assays. Functional analysis indicated that RPS15A knockdown could inhibit cell proliferation, induced cell cycle arrest and apoptosis. Mechanism analysis revealed RPS15A mediated apoptosis via activating of caspase-3 and PARP cleavage, upregulating of Bad and BAX and downregulating of Bcl-2. Our preliminary study highlighted the importance of RPS15A in breast cancer growth. The inhibition of RPS15A may be a promising therapeutic target for breast cancer treatment.

The protective effects of gonadotropin-releasing hormone agonist on ovarian functions in breast Cancer patients receiving chemotherapy.

In recent decades, the incidence rate of breast cancer has increased dramatically worldwide and has become one of the most prevalent cancers in women. According to the global data provided by the WHO, there were more than 1.7 million new cases of breast cancer in 2012, accounting for 25% of all reported cancer cases and 15% of all reported deaths among females. To most young patients, especially those younger than 40 years of age, chemotherapy should be taken into consideration as a treatment modality, even if the tumor size is small or without lymphatic metastasis. A significant portion of the patients will suffer from the side effects that result from long-term chemotherapy regimens, such as myelosuppression, heart failure, and development of a second primary malignancy. Ovarian suppression and premature ovarian failure (POF) are the most common side effects reported as they have notable clinical symptoms; the incidence rates have been reported to be in a range of 10-90%. Gonadotropin-releasing hormone agonists (GnRH-a), also termed luteinizing hormone release hormone agonists (LHRH-a), may very well offer a solution to treating these side effects. This article aims to summarize advanced studies concerning protective effects of GnRH-a on ovarian functions in the setting of breast cancer under chemotherapy.

The effect of adjuvant chemotherapy in male breast cancer: 134 cases from a retrospective study.

BACKGROUND: Male breast cancer (BC) is a kind of rare tumour. There were few researches concerning the effect of chemotherapy for it. The purpose of this study is to estimate the value of chemotherapy on prognosis in male BC. PATIENTS AND METHODS: Complete clinical and pathological information of male BC were collected from January 1990 to January 2008 in Zhejiang Cancer Hospital in China. 134 cases of male BC were included for analysis and separated into two groups based on receiving chemotherapy or not receiving chemotherapy. The disease-free survival (DFS) and overall survival (OS) between chemotherapy group and non-chemotherapy group were compared with Kaplan-Meier survival curve. Stratified analysis was used to evaluate the strength of the association between chemotherapy and each risk factor. Multivariate analysis was conducted by using COX proportional hazard regression model. RESULTS: There were 58.21% (78/134) cases who underwent chemotherapy and 41.79% (56/134) cases without chemotherapy. There were 20 cases (25.64%) with recurrence/metastasis in patients with chemotherapy and six cases (10.71%) in patients without chemotherapy. The mean DFS time of male BC with chemotherapy and non-chemotherapy is 150.87 and 154.13 months, respectively (χ2=3.825, p=0.050). The mean OS time of male BC with chemotherapy and non-chemotherapy is 155.33 and 154.26 months, respectively (χ2=2.542, p=0.111). COX proportional hazard regression model showed that the two groups had similar DFS (HR=0.386, p=0.165), while chemotherapy might be a protective fact on OS (HR=0.140, p=0.026). CONCLUSION: The utility of chemotherapy should be considered in the high risk level of recurrence/metastasis in male BC.

Clinicopathological Characteristics of Mucinous Breast Cancer: A Retrospective Analysis of a 10-Year Study.

BACKGROUND: Mucinous breast carcinoma (MC) is a special type of breast cancer that presents with a large amount of extracellular mucin. MC comprises approximately 4% of all invasive breast cancers. This type of tumor has a better prognosis and higher incidence in peri- and post-menopausal patients. Pathologically, there are two main subtypes of MC: pure and mixed. In this study, we describe 10 years of experience with MC at the Zhejiang Cancer Hospital in China, specifically, clinical data, histological findings and immunohistochemical features. METHODS: We identified MC patients who were diagnosed as operable and completed clinical treatment from January 2001 to January 2011. The clinicopathological data included the age at diagnosis, tumor size, TNM stage, presence and number of lymph node (LN) metastases, estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) status and p53 expression. If the tumor was defined as mixed mucinous carcinoma (MMC), IHC was performed on a non-mucinous part, such as invasive ductal and lobular cancer. We evaluated the clinical characteristics of all MC patients using chi-square, one-way ANOVA and LSD tests. We also studied the correlations between all of the clinical parameters and LN metastasis in a binary logistic regression analysis. We used ten consecutive years of data that were collected at Zhejiang Cancer Hospital. RESULTS: We identified 48 cases of pure mucinous carcinoma (PMC) and 77 cases of MMC. The 48 PMC cases consisted of 38 PMC-A and 10 PMC-B subtypes. The MMCs were divided into two groups, those with partial mixed mucinous breast carcinoma (pMMC, 58 cases) and those with main mixed mucinous breast carcinoma (mMMC, 19 cases). pMMC was defined by tumors with less than 50% mucinous components, while mMMC was defined by tumors where the mucinous component accounted for 50% to 90% of the tumor. No significant differences in the clinicopathological characteristics were noted between the patients with PMC-A and those with PMC-B. The tumor size was larger in the mMMC than PMC cases (44.84 mm vs. 30.06 mm, p = 0.021). The number of positive LN metastases was greater in pMMC than PMC patients (p = 0.024). The clinical stages were significantly different among the three groups, with the pMMC group having more stage III-IV patients than the other two groups (p = 0.005). The incidence of LN metastasis was also higher in the pMMC cases (pMMC vs. mMMC and PMC, 50% vs. 31.58% and 18.75%, p = 0.003). The PMC patients had much lower p53 expression than the other two groups (PMC vs. pMMC and mMMC, 27.08% vs. 55.17% and 57.89%, p = 0.007). The tumor size (>30mm), p53 expression and less proportion of the mucinous component are associated with risk of LN metastasis. CONCLUSION: Based on the results of this study, we conclude that the tumor size, status of LN metastasis, clinical stage, and p53 mutation rate may differ between MMC and PMC patients. The tumor size (>30mm), p53 mutation and less proportion of the mucinous component should be considered risk factors of LN metastasis in MC patients.

CK19 mRNA in blood can predict non-sentinel lymph node metastasis in breast cancer.

Reverse-transcription polymerase chain reaction (RT-PCR) is used to detect CK19 mRNA in sentinel lymph node biopsy (SLNB) tissues from breast cancer patients. We examined whether CK19 mRNA in peripheral blood is predictive of non-sentinel lymph node (nSLN) metastasis. Breast cancer cases diagnosed with clinical stage cT1-3cN0 and registered in our medical biobank were identified retrospectively. This study then included 120 breast cancer cases treated at Zhejiang Cancer Hospital from Aug 2014 to Aug 2015, including 60 SLN-positive and 60 SLN-negative cases. CK19 mRNA levels in peripheral blood samples were assessed using RT-PCR prior to tumor removal. During surgery, if SLNB tissue showed evidence of metastasis, axillary lymph node dissection (ALND) was performed. No ALND was performed if SLNB and nSLN tissues were both negative for metastasis. CK19 expression was higher in nSLN-positive patients than in nSLN-negative patients (p < 0.05). Logistic regression indicated that lymphatic vessel invasion and CK19 levels were predictive of nSLN status (p < 0.05). The area under the ROC curve for CK19 was 0.878 (p < 0.05). We conclude that high CK19 levels in peripheral blood may independently predict nSLN metastasis in breast cancer patients.

PAX6 overexpression is associated with the poor prognosis of invasive ductal breast cancer.

Paired box 6 (PAX6) plays a significant role in the development of human neuroectodermal epithelial tissues. Previous studies have suggested that the PAX6 promoter is hypermethylated in breast cancer and that it is involved in breast cancer cell proliferation. The present study aimed to investigate the expression of PAX6 in invasive breast cancer tissues, and to evaluate its prognostic significance. Immunohistochemistry (IHC) was used to detect PAX6 expression on a breast cancer tissue microarray containing tissues from 111 patients. Associations of PAX6 expression with staging and prognosis were analyzed. PAX6 was mainly expressed in the nucleus. The PAX6 staining intensity was not associated with age, histological grade, lymph node status, tumor size, or progesterone receptor and human epidermal growth factor receptor 2 expression (all P>0.05). A high level of PAX6 staining was more frequent in estrogen receptor (ER)-negative cases compared with ER-positive cases (43.9 vs. 25.7%; P=0.049). After a median follow-up time of 110 months, the patients with low PAX6 expression exhibited an improved survival rate compared with the patients with high PAX6 expression (P<0.001). Cox analysis showed a worse survival rate in the patients with high PAX6 staining (hazard ratio, 3.458; 95% confidence interval, 1.575-7.593; P=0.002). In conclusion, high tumor PAX6 staining intensity by IHC was associated with a poor prognosis in breast cancer patients.

A Prognostic Analysis of Male Breast Cancer (MBC) Compared with Post-Menopausal Female Breast Cancer (FBC).

BACKGROUND: Male breast cancer (MBC) is known to be rare compared with female breast cancer (FBC) and to account for only 1% of all breast cancers. To date, male patients diagnosed with breast cancer are normally treated based on the guidelines for FBC. Specifically, studies have found that diagnosing and treating MBC patients under the guidelines for the treatment of post-menopausal FBC are more favorable than are those of pre/peri-menopausal FBC from a physiological perspective because MBC and post-menopausal FBC patients show high estrogen receptor (ER) expression in the tumor and low estrogen expression in the body. In this medical study, we aimed to examine whether MBC actually has the same prognosis as post-menopausal FBC. METHOD: We identified MBC patients who were diagnosed as operable and who completed clinical treatment and we used follow-up data that were collected from January 2001 to January 2011. Each MBC patient was paired with four FBC patients who were diagnosed within the same period (two were pre/peri-menopausal, and two were post-menopausal). We compared disease-free survival (DFS) and overall survival (OS) among three groups, i.e., pre/peri-menopausal FBC (group A), post-menopausal FBC (group B) and MBC (group M), using the Kaplan-Meier method and a Cox proportional hazards regression model. We also evaluated the clinical characteristics of breast cancer patients using t-tests and chi-square tests. We used ten consecutive years of data that were collected at Zhejiang Provincial Cancer Hospital. RESULTS: We identified 91 MBC cases for group M, 182 FBC cases for group A and 182 FBC cases for group B. The median follow-up period was 112 months. MBC cases were much more frequently ER positive than those of group A and group B (p<0.01); a similar trend was also found for progesterone (PR)-positive cases (p<0.01). The MBC group showed much lower human epidermal growth factor receptor-2 (HER2) expression than did the other groups (p<0.01). The 10-year OS rates were 79.1% for group M (72/91), 79.1% (144/182) for group A, and 87.9% (160/182) for group B, log-rank test indicated that group M had similar mean OS time as group A and group B (GourpM vs group A: p = 0.709; group M vs group B: p = 0.042). The Cox proportional hazards regression model indicated that pre/peri-menopausal FBC had similar DFS (hazard ratio (HR) = 0.706, p = 0.262) and OS (HR = 1.029, p = 0.941) values compared with MBC, whereas post-menopausal FBC had higher DFS (HR = 0.454, p = 0.004) and OS (HR = 0.353, p = 0.003) values than did MBC. CONCLUSION: Based on this study, we can conclude that MBC displayed higher ER- and PR-positive expression and lower HER2-positive expression than both post-menopausal and pre/peri-menopausal FBC. However, the DFS and OS values of MBC were similar to those of pre/peri-menopausal FBC and were worse than were those of post-menopausal FBC.

Down-regulation of asparagine synthetase induces cell cycle arrest and inhibits cell proliferation of breast cancer.

Asparagine synthetase (ASNS) is deemed to be a promising therapeutic target for the treatment of several cancers, but its functional role in human breast cancer is still unknown. In this study, we employed RNA interference as an efficient tool to silence endogenous ASNS expression in breast cancer cell lines. The relationship between ASNS expression and breast cancer cell growth was investigated, and the therapeutic value of ASNS in breast cancer was further evaluated. Depletion of ASNS remarkably inhibited the proliferation and colony formation capacity of breast cancer cells and arrested cell cycle in the S phase. Our findings suggest that ASNS may contribute to breast cancer tumorigenesis and could be a potential therapeutic target in human breast cancer.

shRNA-mediated silencing of ZFX attenuated the proliferation of breast cancer cells.

PURPOSE: Breast cancer is the cause for highest number of cancer-related death among women worldwide. This study was focused on investigating the role of zinc-finger protein X-linked (ZFX) in human breast cancer. METHODS: Expression levels of ZFX were analyzed in 99 patients and four breast cancer cell lines. Lentivirus-mediated RNA interference was applied to silence ZFX expression, and the effects of ZFX knockdown on the growth of breast cancer cells were investigated. RESULTS: The immunohistochemical expression of ZFX was higher in more advanced tumor tissues. ZFX was also overexpressed in multiple breast cancer cell lines. Knockdown of ZFX inhibited cell proliferation and colony formation of MCF-7 and MDA-MB-231 cells. Moreover, ZFX silencing resulted in cell cycle arrest at G0/G1 phase. Depletion of ZFX decreased the phosphorylation level of AKT and increased the phosphorylation level of ERK2 and the expression of cyclin D1, which is involved in cell survival and cell cycle regulation. CONCLUSIONS: These findings suggest that ZFX plays an important role in breast cancer development and could be a potential therapeutic target for breast cancer.