ABCC5 supports osteoclast formation and promotes breast cancer metastasis to bone

Introduction

Bone is the most common site of breast cancer metastasis, and complications associated with bone metastases can lead to a significantly decreased patient quality of life. Thus, it is essential to gain a better understanding of the molecular mechanisms that underlie the emergence and growth of breast cancer skeletal metastases.

Methods

To search for novel molecular mediators that influence breast cancer bone metastasis, we generated gene-expression profiles from laser-capture microdissected trephine biopsies of both breast cancer bone metastases and independent primary breast tumors that metastasized to bone. Bioinformatics analysis identified genes that are differentially expressed in breast cancer bone metastases compared with primary, bone-metastatic breast tumors.

Results

ABCC5, an ATP-dependent transporter, was found to be overexpressed in breast cancer osseous metastases relative to primary breast tumors. In addition, ABCC5 was significantly upregulated in human and mouse breast cancer cell lines with high bone-metastatic potential. Stable knockdown of ABCC5 substantially reduced bone metastatic burden and osteolytic bone destruction in mice. The decrease in osteolysis was further associated with diminished osteoclast numbers in vivo. Finally, conditioned media from breast cancer cells with reduced ABCC5 expression failed to induce in vitro osteoclastogenesis to the same extent as conditioned media from breast cancer cells expressing ABCC5.

Conclusions

Our data suggest that ABCC5 functions as a mediator of breast cancer skeletal metastasis. ABCC5 expression in breast cancer cells is important for efficient osteoclast-mediated bone resorption. Hence, ABCC5 may be a potential therapeutic target for breast cancer bone metastasis.     

Primary breast cancer stem-like cells metastasise to bone,switch phenotype and acquire a bone tropism signature

Background:

Bone metastases represent a common and severe complication in breast cancer, and the involvement of cancer stem cells (CSCs) in the promotion of bone metastasis is currently under discussion. Here, we used a human-in-mice model to study bone metastasis formation due to primary breast CSCs-like colonisation.

Methods:

Primary CD44⁺CD24⁻ breast CSCs-like were transduced by a luciferase-lentiviral vector and injected through subcutaneous and intracardiac (IC) routes in non-obese/severe-combined immunodeficient (NOD/SCID) mice carrying subcutaneous human bone implants. The CSCs-like localisation was monitored by in vivo luciferase imaging. Bone metastatic CSCs-like were analysed through immunohistochemistry and flow cytometry, and gene expression analyses were performed by microarray techniques.

Results:

Breast CSCs-like colonised the human-implanted bone, resulting in bone remodelling. Bone metastatic lesions were histologically apparent by tumour cell expression of epithelial markers and vimentin. The bone-isolated CSCs-like were CD44⁻CD24⁺ and showed tumorigenic abilities after injection in secondary mice. CD44⁻CD24⁺ CSCs-like displayed a distinct bone tropism signature that was enriched in genes that discriminate bone metastases of breast cancer from metastases at other organs.

Conclusion:

Breast CSCs-like promote bone metastasis and display a CSCs-like bone tropism signature. This signature has clinical prognostic relevance, because it efficiently discriminates osteotropic breast cancers from tumour metastases at other sites.     

骨转换标志物在非小细胞肺癌骨转移临床应用价值的研究

Objective  

The purpose of this study was to assess the clinical application value of bone turnover markers in non-small-cell lung cancer (NSCLC) patients with bone metastases. Including diagnosing bone metastases, detecting bone metastatic spread.     

Benefits of using the cell block method to determine the discordance of the HR/HER2 expression in patients with metastatic breast cancer

Background

The discordance of the hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) expressions between primary cancer and metastatic lesions is an important issue when selecting the optimal treatments for patients with metastatic breast cancer. A rebiopsy for the metastatic cancer is recommended before selecting the treatment; however, it is not easy to take a tissue sample for all metastatic lesions. Fine needle aspiration cytology (FNA) for regional lymph nodes and aspiration for pleural effusions or ascites are less invasive procedures to obtain the necessary samples to examine the HR/HER2 expression. These cytologic materials are able to be stained as a tissue sample using the cell block method.

Patients

We examined the HR/HER2 expression of 20 patients with breast cancer (8 with synchronous metastases and 12 with metachronous metastases) using the cell block method. Among 8 patients with synchronous metastases, 7 patients with axillary lymph node (LN) metastasis were examined by fine needle aspiration (FNA), and one patient with pleural metastases was analyzed for the aspirated fluid. While in 12 patients with metachronous metastases, 7 patients were examined for their pleural effusion, 3 patients were examined for regional lymph node metastases, and 1 patient were examined for aspirated ascites. We compared the HR/HER expression between primary cancer and metastatic lesion in 17 patients (5 cases of 8 synchronous metastases, and all of 12 metachronous metastases).

Results

Discordance of HR was seen in 4 of 17 patients (24 %). Three cases with axillary LN metastasis (2 cases with synchronous metastases and one with metachronous metastasis) showed negative change of ER. Negative change of HER2 expression was seen in one patient with ascites caused by peritoneal dissemination.

Conclusions

Cytology materials are easily obtained by FNA for LN metastases and aspiration for malignant effusions and analyzed for HR/HER2 expression using cell block method. We should take advantage of cell block analysis to determine the discordance of the HR/HER2 expression to select the optimal treatment for metastatic breast cancer.

     

Breast Osteoblast-like Cells: A Reliable Early Marker for Bone Metastases From Breast Cancer

Background

The development of bone metastasis from breast cancer results from a functional interaction between tumor cells and osteoclasts or osteoblasts. The main aim of this study was therefore to test the hypothesis that the appearance of breast osteoblast-like cells (BOLCs) in primary mammary lesions is a precursor (and hence an early predictor) of the formation of breast cancer metastases to bone.

Liver metastases from breast cancer: Surgical resection or not? A case-matched control study in highly selected patients

Aim

To determine whether, in a highly selected patient population, medical treatment combined with surgical resection of liver metastases from breast cancer is associated with improved survival compared with medical treatment alone.

Patients and methods

Between 1988 and 2007, 100 liver resections for metastatic breast cancer were performed at Institut Curie, 51 of which met the criteria for inclusion in this case-control study. With the exception of bone metastases, patients with other distant metastasis sites were excluded. Surgery was only performed in patients with stable disease or disease responding to medical treatment evaluated by imaging evaluation. Surgical cases were individually matched with 51 patients receiving medical treatment only. All patients had 4 or fewer resectable liver metastases. The study group was matched with the control group for age, year of breast cancer diagnosis, time to metastasis, TNM stage, hormone receptor status and breast cancer tumour pathology.

Results

Univariate analysis confirmed a survival advantage for patients lacking bone metastases and axillary lymphadenopathy at the time of breast cancer diagnosis and for surgically treated patients. Multivariate analysis indicated that surgery and the absence of bone metastases were associated with a better prognosis. A multivariate Cox model adapted for paired data showed a RR = 3.04 (CI: 1.87–4.92) (p < 0.0001) in favour of surgical treatment.

Conclusion

Surgical resection of liver metastases from primary breast cancer appears to provide a survival benefit for highly selected patients.     

Post-operative breast cancer patients diagnosed with skeletal metastasis without bone pain had fewer skeletal-related events and deaths than those with bone pain

Background  

Skeletal metastases are often accompanied by bone pain. To investigate the clinical meaning of bone pain associated with skeletal metastasis in breast cancer patients after surgery, we explored whether the presence of bone pain was due to skeletal-related events (SREs) or survival (cause specific death, CSD), retrospectively.     

Incidence of bone metastases and skeletal-related events in breast cancer patients: A population-based cohort study in Denmark

Background  

Breast cancer (BrCa) is the most commonly diagnosed cancer among women in the industrialized world. More than half of women presenting with metastatic BrCa develop bone metastases. Bone metastases increase the risk of skeletal-related events (SREs), defined as pathological fractures, spinal cord compression, bone pain requiring palliative radiotherapy, and orthopaedic surgery. Both bone metastases and SREs are associated with unfavorable prognosis and greatly affect quality of life. Few epidemiological data exist on SREs after primary diagnosis of BrCa and subsequent bone metastasis. We therefore estimated the incidence of bone metastases and SREs in newly-diagnosed BrCa patients in Denmark from 1999 through 2007.     

Pain control with zoledronic acid in patients with breast cancer and metastatic bone disease

Background

Effective management of pain associated with metastatic bone disease is paramount in the care of cancer patients. Bisphosphonates are recommended in treating skeletal complications and there is evidence that they also control pain.

Objective

To investigate the effects of zoledronic acid, a potent nitrogen-containing bisphosphonate, in reducing pain in patients with advanced breast cancer and bone metastases.

Patients and methods

Thirty-two patients (age range 37–79 years, median 56 years) with histologically proven breast cancer and bone metastases received a 15-minute infusion of zoledronic acid 4mg every 4 weeks for a mean of eight cycles (range 1–13) in a phase II pilot study. The primary efficacy endpoint was the control of pain as determined by changes in pain and analgesic scores.

Results

Zoledronic acid substantially reduced pain scores compared with baseline, with over 80% of patients reporting mild or no pain at the end of the trial (82% had moderate to very severe pain on entry). The percentage of patients requiring no analgesics increased from 9% to 35% following zoledronic acid treatment. At baseline, 47% of patients required opioids to control pain, whereas 27% required opioids at the end of the trial. Zoledronic acid appeared to be well tolerated, with no patients reporting serious adverse events.

Conclusion

These results support previous data indicating that zoledronic acid is effective in patients with breast cancer and painful bone metastases. Follow-up controlled trials are required to further investigate the role of zoledronic acid in the management of cancer patients with metastatic disease.     

Breast cancer primary tumor ER expression pattern predicts its expression concordance in matched synchronous lymph node metastases

Background

Estrogen receptor (ER) expression is important for treatment selection and prognostication of breast cancer patients. Although the metastases are the main targets of endocrine therapy, ER status is often based on the primary tumor. However, ER expression in breast cancer primary lesion may not match with its synchronous metastatic lesions in some cases. In this study, we analyzed ER expression concordance between breast cancer primary tumor and metastatic lesions.

Methods

Paraffin blocks of 100 primary breast invasive ductal carcinoma cases with axillary lymph node metastases were collected. Five tissue cores were punched out from individual primary breast cancer, and one tissue core from each lymph node metastases to assemble tissue microarrays for ER staining. Samples were then scored as 0, 1+, 2+, and 3+ according to the number and intensity of ER stained tumor cells.

Results

For cases with ER 3+ (strong expression) in all cores of primary lesions (n?=?38), ER expression in metastatic lymph node was found in 94.7% of the patients. 91.0% of the metastatic lymph nodes were ER positive, and 84.3% of them to be 3+. Among the 46 cases of ER negative expression in all cores of primary lesions, 39 of them had all the metastatic nodes being ER negative, and ER negative nodes were seen in 95.7% of the metastases. As for 16 cases of ER inconsistent expression in primary lesions, 4 cases showed negative ER expression in all metastatic nodes, 2 cases displayed diffuse consistent ER 3+ expression, and 10 cases displayed variant ER expression.

Conclusions

The findings suggest that ER expression concordance between breast cancer primary lesion and its matched metastatic lesions could be estimated by primary tumor ER expression pattern.

     

Incidence and prognostic significance of receptor discordance between primary breast cancer and paired bone metastases

ER, PgR and HER-2 status are the cornerstones of choosing systemic therapy for breast cancer, but can change during the disease course. Guidelines recommended the biopsy of the metastatic tumor to reassess receptor status. Bone is the most frequent metastatic site of breast cancer but remained technically difficult to biopsy. Our study aimed to evaluate the incidence and prognostic significance of receptor discordance between primary breast cancer and paired bone metastases. One hundred and fifty-five breast cancer patients were diagnosed with pathology-confirmed bone metastasis at Fudan University Shanghai Cancer Center. Ninety-three patients with receptor status available on both primary tumor and bone metastases were included in our study. ER, PgR and HER-2 status converted from positive to negative in 10.8% (10/93), 28.0% (26/93) and 8.6% (8/93) of the patients, while ER, PgR and HER-2 status converted from negative to positive in 3.2% (3/93), 4.3% (4/93) and 1.1% (1/93) of the patients, respectively. 40.4% (17/42) of the HER2-0 tumors converted to HER2-low, which enabled them to receive the treatment of new antibody-drug conjugates (ADCs). Prior endocrine and anti-HER2 therapy were the independent risk factors for receptor conversion. Loss of HR expression in bone metastases was significantly associated with worse first-line PFS (adjusted hazard ratio = 3.271, P-value = .039) and OS (adjusted hazard ratio = 6.09, P-value = .011). In conclusion, our study confirmed that patients may experience receptor conversion between primary breast cancer and bone metastases, possibly influenced by prior treatments, which significantly influenced prognosis. The rebiopsy of bone metastases in patients with primary HER2-0 tumors may benefit from the new ADC drugs.     

Role of HYAL1 expression in primary breast cancer in the formation of brain metastases

Background

The incidence of brain metastases in breast cancer patients has increased in the last years. However, the knowledge about tumor cell invasion in the brain is still very limited. Based on our recent study on cDNA microarray data of breast cancer patients, we hypothesized that two enzymes involved in the hyaluronan metabolism, namely, hyaluronan synthase 2 (HAS2) and hyaluronidase 1 (HYAL1) are associated with brain metastases formation.

Methods

Protein expression levels of hyaluronan, HAS2, and HYAL1 were analyzed in primary breast cancer, and metastatic tissue samples from different localizations (brain, bone, skin, liver, and lung) were included in four different cohorts by immunohistochemistry. Correlations of expression levels with clinical and pathological parameters were performed within the individual cohorts.

Results

Higher HYAL1 expression was detected among primary tumors from patients with subsequent brain metastases compared with those without brain metastases (p = 0.011). Interestingly, brain metastatic tissue showed a significantly reduced HYAL1 expression compared with the corresponding primary tumor (p = 0.003). HYAL1 expression in brain metastases was also significantly lower than in skin, liver, and lung metastases. Further, hyaluronan staining in brain metastases was mainly located on the surface of the tumor cells, whereas in all other metastatic sites hyaluronan was only detected in the extracellular matrix. We could not show an association of HAS2 with the formation of brain metastases.

Conclusions

In conclusion, our results suggest that the enzyme HYAL1 plays a role in tumor dissemination and brain-specific colonization, rather than in subsequent metastatic out-growth.

     

Increased tartrate-resistant acid phosphatase (TRAP) expression in malignant breast, ovarian and melanoma tissue: an investigational study

Background  

Tartrate-resistant acid phosphatase (TRAP) is a metalloprotein enzyme that belongs to the acid phosphatases and is known to be expressed by osteoclasts. It has already been investigated as a marker of bone metastases in cancer patients. In this study, which examined the value of serum TRAP concentrations as a marker of bone disease in breast cancer patients, we observed high concentrations of TRAP even in patients without bone metastases. To elucidate this phenomenon, we examined the expression of TRAP in breast cancer cells and the cells of several other malignancies.     

Potential antitumor effects of nitrogen-containing bisphosphonate in hormone receptor negative breast cancer patients with bone metastases

Background  

This retrospective study evaluated, according to hormone receptor status, the antitumor effects of bisphosphonate especially on survival and disease progression in breast cancer patients with metastatic bone disease.     

Tumor-specific expression of αvβ3 integrin promotes spontaneous metastasis of breast cancer to bone

Introduction  

Studies in xenograft models and experimental models of metastasis have implicated several β3 integrin-expressing cell populations, including endothelium, platelets and osteoclasts, in breast tumor progression. Since orthotopic human xenograft models of breast cancer are poorly metastatic to bone and experimental models bypass the formation of a primary tumor, however, the precise contribution of tumor-specific αvβ3 to the spontaneous metastasis of breast tumors from the mammary gland to bone remains unclear.     

Quantitation of sentinel node metastatic burden and Her-2/neu over-expression accurately predicts residual axillary nodal involvement and extranodal disease in breast cancer

Background data

Recent literature has suggested that completion axillary lymph node dissection (ALND) in breast carcinoma patients with positive SLN may not be necessary. However, a method for determining the risk of non-SLN or extranodal disease remains to be established.

Aims

To determine if pathological variables from primary tumors and sentinel lymph node (SLN) metastases could predict the probability of non-sentinel lymph node (NSLN) metastases and extranodal disease in patients with breast carcinoma and SLN metastases.

Methods

84 women with T1-3 breast cancer and clinically-negative axillae underwent completion ALND. Maximum diameter and width of SLN metastases were measured to calculate metastatic area. When multiple SLNs contained metastases, areas were summed to calculate the Total Metastatic Area (TMA). Multiple linear regression models were used to identify predictive factors.

Results

Her-2/neu over-expression increased the odds of NSLN metastases (OR 4.3, p = 0.01) and extranodal disease (OR 7.9, p < 0.001). Independent SLN predictors were ≥1 positive SLN (OR, 7.35), maximum diameter and area of SLN metastases (OR 2.26, 1.85 respectively) and TMA (OR, 2.12). Maximum metastatic diameter/SLN diameter (OR 3.71, p = 0.04) and the area of metastases/SLN area (OR 3.4, p = 0.04) were predictive. For every 1 mm increase in diameter of SLN metastases, the odds of NSLN extranodal disease increased by 8.5% (p = 0.02). TMA >0.40 cm² was an independent predictor for NSLN metastases and extranodal disease.

Conclusion

Her-2/neu over-expression and parameters assessing metastatic burden in the SLN, particularly TMA, predicted the presence of NSLN involvement and extranodal disease in patients with breast carcinoma and SLN metastases.     

E-cadherin expression in primary carcinomas of the breast and its distant metastases

Introduction  

Aberrant expression of E-cadherin has been associated with the development of metastases in patients with breast cancer. Even though the expression of E-cadherin has been studied in primary breast tumors, little is known about its expression at the distant metastatic sites. We investigate the relationship between E-cadherin expression in primary breast carcinoma and their distant, non-nodal metastases.     

A prospective, randomized, placebo-controlled trial of zoledronic acid in bony metastatic bladder cancer

Background  

Zoledronic acid treatment reduces the incidence of skeletal-related events (SREs) in patients with bone metastases from breast, lung, and urologic cancers including prostate and renal cancer. The aim of this study was to evaluate the effect of zoledronic acid on SREs in patients with bone metastases from bladder cancer.