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Breast Cancer Metastases (breast + cancer_metastase)
Selected AbstractsIdentification of prospective factors promoting osteotropism in breast cancer: a potential role for CITED2INTERNATIONAL JOURNAL OF CANCER, Issue 4 2010Wen Min Lau Abstract Breast cancer metastases develop in the bone more frequently than any other site and are a common cause of morbidity in the form of bone pain, pathological fractures, nerve compression and life-threatening hypercalcemia. Despite ongoing research efforts, the molecular and cellular mechanisms that regulate breast cancer cell homing to and colonization of the bone as well as resultant pathological bone alteration remain poorly understood. To identify key mediators promoting breast cancer metastasis to bone, we utilized an immunocompetent, syngeneic murine model of breast cancer metastasis employing the mammary tumor cell line NT2.5. Following intracardiac injection of NT2.5 cells in neu-N mice, metastases developed in the bone, liver and lung, closely mimicking the anatomical distribution of metastases in patients with breast cancer. Using an in vivo selection process, we established NT2.5 sublines demonstrating an enhanced ability to colonize the bone and liver. Genome-wide cDNA microarray analysis comparing gene expression between parental NT2.5 cells and established sublines revealed both known and novel mediators of bone metastasis and osteolysis, including the transcriptional co-activator CITED2. In further studies, we found that expression of CITED2 was elevated in human primary breast tumors and bone metastasis compared to normal mammary epithelium and was highest in breast cancer cell lines that cause osteolytic bone metastasis in animal models. In addition, reducing CITED2 expression in NT2.5 cells inhibited the establishment of bone metastasis and osteolysis in vivo, suggesting a potential role for CITED2 in promoting breast cancer bone metastasis. [source] Breast cancer-derived Dickkopf1 inhibits osteoblast differentiation and osteoprotegerin expression: Implication for breast cancer osteolytic bone metastasesINTERNATIONAL JOURNAL OF CANCER, Issue 5 2008Guojun Bu Abstract Most breast cancer metastases in bone form osteolytic lesions, but the mechanisms of tumor-induced bone resorption and destruction are not fully understood. Although it is well recognized that Wnt/,-catenin signaling is important for breast cancer tumorigenesis, the role of this pathway in breast cancer bone metastasis is unclear. Dickkopf1 (Dkk1) is a secreted Wnt/,-catenin antagonist. In the present study, we demonstrated that activation of Wnt/,-catenin signaling enhanced Dkk1 expression in breast cancer cells and that Dkk1 overexpression is a frequent event in breast cancer. We also found that human breast cancer cell lines that preferentially form osteolytic bone metastases exhibited increased levels of Wnt/,-catenin signaling and Dkk1 expression. Moreover, we showed that breast cancer cell-produced Dkk1 blocked Wnt3A-induced osteoblastic differentiation and osteoprotegerin (OPG) expression of osteoblast precursor C2C12 cells and that these effects could be neutralized by a specific anti-Dkk1 antibody. In addition, we found that breast cancer cell conditioned media were able to block Wnt3A-induced NF-kappaB ligand reduction in C2C12 cells. Finally, we demonstrated that conditioned media from breast cancer cells in which Dkk1 expression had been silenced via RNAi were unable to block Wnt3A-induced C2C12 osteoblastic differentiation and OPG expression. Taken together, these results suggest that breast cancer-produced Dkk1 may be an important mechanistic link between primary breast tumors and secondary osteolytic bone metastases. © 2008 Wiley-Liss, Inc. [source] The role of cytokeratins 20 and 7 and estrogen receptor analysis in separation of metastatic lobular carcinoma of the breast and metastatic signet ring cell carcinoma of the gastrointestinal tractAPMIS, Issue 7-8 2000TIBOR Tot Metastatic signet ring cell carcinomas of unknown primary site can represent a clinical problem. Gastrointestinal signet ring cell carcinomas and invasive lobular carcinomas of the breast are the most common sources of these metastases. Immunohistochemical algorithms have been successfully used in the search for the unknown primary adenocarcinomas. In the present study a series of primary invasive lobular breast carcinomas (79 cases) and their metastases and a series of gastrointestinal signet ring cell carcinomas (22 primary and 13 metastases) were stained with monoclonal antibodies for cytokeratin (CK) 20 and CK7 and for estrogen receptors (ER). The staining was evaluated as negative (no staining), focally (less than 10% of the tumor cells stained) or diffusely positive. All the primary and metastatic gastrointestinal signet ring cell carcinomas proved to be CK20 positive, while only 2/79 (3%) of the primary and 1/21 metastatic lobulr carcinomas (5%) stained positively for this CK. None of the gastrointestinal carcinomas and the majority of the lobular carcinomas expressed ER. The majority of the tumors were CK7+. Using CK20 alone, 33 of 34 metastases could be properly classified as gastrointestinal (CK20+) or mammary (CK20-). ER identified 31/34 of breast cancer metastases. By combining the results of CK20 and ER staining all the metastases could be properly classified as the CK20+/ER- pattern identified all the gastrointestinal tumors. [source] The role of chemoattraction in cancer metastasesBIOESSAYS, Issue 8 2001Malcolm A.S. Moore It has long been unclear as to why particular cancers preferentially metastasize to certain sites. The possibilities usually discussed involve differential survival and proliferation at these sites, or selective trapping with or without preferential homing. A recent report by Muller et al.(1) provides evidence for preferential homing of breast cancer to metastatic sites. The findings indicate that the chemokine receptors CXCR4 and CCR7 are found on breast cancer cells and their ligands are highly expressed at sites associated with breast cancer metastases. This results in chemotaxis, or directed migration of tumor cells from their primary site via the circulation to the preferential sites of metastases. The evidence for this model and its significance are reviewed here. BioEssays 23:674,676, 2001. © 2001 John Wiley & Sons, Inc. [source] Detection of micrometastases in lymph nodes from patients with breast cancerBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 1 2002G. Branagan Background: Sentinel node biopsy affords the opportunity of focused examination of lymph nodes, including the use of the reverse transcriptase,polymerase chain reaction (RT-PCR). The mammaglobin gene is expressed by breast cancers but has not been detected in histologically normal lymph nodes. This study compared mammaglobin RT-PCR with routine histology in the sentinel and non-sentinel nodes of patients with breast cancer. Methods: Patients with breast cancer underwent tumour excision, sentinel node biopsy and axillary dissection. All nodes were bisected and half of each node was sent for routine histological examination. The other half underwent RNA extraction and mammaglobin RT-PCR. Results: Sentinel node biopsy was successful in 50 (96 per cent) of 52 patients. Mammaglobin expression was detected in nine (8 per cent) of 119 histologically negative sentinel nodes (Clopper,Pearson 95 per cent confidence interval (c.i.) 4 to 14 per cent) and in 13 (5 per cent) of 247 histologically negative non-sentinel nodes (95 per cent c.i. 3 to 9 per cent). Mammaglobin expression was detected in four (13 per cent) of 31 patients with histologically negative sentinel nodes (95 per cent c.i. 4 to 30 per cent) and in six (14 per cent) of 44 patients with histologically negative non-sentinel nodes (95 per cent c.i. 5 to 27 per cent). The false-negative rate for sentinel node biopsy was zero using histology results and 10 per cent using RT-PCR. Conclusion: RT-PCR screening of axillary nodes for mammaglobin expression increased the detection of breast cancer metastases compared with routine histology. © 2002 British Journal of Surgery Society Ltd [source] A prospective pilot study of curative-intent stereotactic body radiation therapy in patients with 5 or fewer oligometastatic lesions,CANCER, Issue 3 2008Michael T. Milano MD Abstract BACKGROUND. It is hypothesized that oligometastatic disease represents a state of potentially curable, limited metastases. Stereotactic body radiation therapy (SBRT) is an option for patients who are not amenable to or do not want resection. METHODS. From 2001 to 2006, 121 patients with ,5 detectable metastases were enrolled in 2 prospective studies that used curative-intent SBRT. Most patients were treated with 10 fractions of 5 Gray. Stereotactic radiosurgery was offered to patients with brain metastases. RESULTS. The 2-year overall survival (OS), progression-free survival (PFS), local control (LC), and distant control (DC) rates were 50%, 26%, 67%, and 34%, respectively; and the respective 4-year rates values were 28%, 20%, 60%, and 25%. A greater net tumor volume predicted significantly worse OS, PFS, LC, and DC. Patients with breast cancer fared significantly better with respect to OS, PFS, LC, and DC; and patients with adrenal metastases had significantly worse OS, PFS, and DC despite the small number of such patients enrolled. Neither the number of metastatic lesions nor the number of organs involved was a significant predictor of outcome. Among 45 patients who remained alive at the last follow-up, 29 patients had no evidence of disease, including 23 patients with ,2 years of follow-up. CONCLUSIONS. Oligometastatic disease is a potentially curable state of distant cancer spread. In this hypothesis-generating analysis, patients with less volume burden of their metastatic disease and those with primary breast cancer fared better. SBRT delivered with curative intent in patients with limited metastases should be investigated further. The Southwest Oncology Group is developing a prospective protocol to treat women who have limited breast cancer metastases with SBRT. Cancer 2008. © 2007 American Cancer Society. [source] |