Project description:The goal of this study was to evaluate genes that are differentially expressed in the bone stroma when breast cancer metastasis are present. We focused our attention on bone stroma cells to understand how the dissemination and growth of tumor cells can impact on the bone environment. Moreover, we aimed to identify potential targets to inhibit the cross talk between cancer cells and tumor microenvironment in bone metastasis. EO771 breast cancer cell line were engineered to express luciferase and GFP, and injected in C57BL/6 mice by the intracardiac route to obtain bone metastasis. Tumor growth was monitored in-vivo by bioluminescence for 2 weeks. Endothelial cells and osteoblasts were isolated from the long bones of tumor-bearing and tumor-free mice to identify genes differentially expressed.
Project description:The goal of this study was to evaluate genes that are differentially expressed in the bone stroma when breast cancer metastasis are present. We focused our attention on bone stroma cells to understand how the dissemination and growth of tumor cells can impact on the bone environment. Moreover, we aimed to identify potential targets to inhibit the cross talk between cancer cells and tumor microenvironment in bone metastasis. MDA-MB 231 scp1833 breast cancer cell line were engineered to express luciferase and GFP, and injected in NOD-SCID mice by the intracardiac route to obtain bone metastasis. Tumor growth was monitored in-vivo by bioluminescence for 2 weeks. Endothelial cells and osteoblasts were isolated from the long bones of tumor-bearing and tumor-free mice to identify genes differentially expressed.
Project description:The skeleton is the most common metastasis site of breast cancer cells and the molecular underpinning of this process is incompletely understood. The tumor suppressor gene deleted in liver cancer-1 (DLC1) encodes a multi-domain protein including a RhoGTPase activating protein (RhoGAP) domain and has been reported to suppress the lung colonization of breast cancer cells. However, the role of DLC1 in breast cancer bone metastasis and the importance of RhoGAP-dependent and -independent pathways in this process remain unclear. Here, we showed that DLC1 silencing is linked to enhanced bone-tropism of breast cancer cell lines and poor prognosis of clinical samples. In the study presented here, DLC1 was overexpressed in the SCP2 breast cancer cells, and the control SCP2 and overexpression cells were treated with TGFbeta. Microarray profiling of mRNA levels was performed in the control and overexpression cells with or without TGFbeta treatment.
Project description:Bone is the primary site of breast cancer metastasis and complications associated with bone metastases can lead to a significantly decreased quality of life in these patients. 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 micro-dissected trephine biopsies of both breast cancer bone metastases and primary breast tumors that metastasized to bone. Bioinformatics analysis identified genes that are differentially expressed in breast cancer bone metastases compared to primary mammary tumors. Results: ABCC5, an ATP-dependent transporter, was found to be overexpressed in breast cancer osseous metastases relative to primary mammary tumors. In addition, ABCC5 was significantly up-regulated in human and mouse breast cancer cell lines with high bone-metastatic potential. Stable knockdown of ABCC5 significant reduced bone metastatic burden and osteolytic bone destruction in mice. The decrease in osteolysis was further associated with diminished osteoclast numbers. Conclusions: Our data, for the first time, suggests that ABCC5 functions as a mediator of breast cancer skeletal metastasis. ABCC5 expression in breast cancer cells is important for the efficient bone resorption mediated by osteoclasts. Hence, ABCC5 may be a potential therapeutic target for breast cancer bone metastasis. primary breast tumors vs. bone trephine biopsies
Project description:The skeleton is the most common metastasis site of breast cancer cells and the molecular underpinning of this process is incompletely understood. The tumor suppressor gene deleted in liver cancer-1 (DLC1) encodes a multi-domain protein including a RhoGTPase activating protein (RhoGAP) domain and has been reported to suppress the lung colonization of breast cancer cells. However, the role of DLC1 in breast cancer bone metastasis and the importance of RhoGAP-dependent and -independent pathways in this process remain unclear. Here, we showed that DLC1 silencing is linked to enhanced bone-tropism of breast cancer cell lines and poor prognosis of clinical samples.
Project description:Bone is the primary site of breast cancer metastasis and complications associated with bone metastases can lead to a significantly decreased quality of life in these patients. 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 micro-dissected trephine biopsies of both breast cancer bone metastases and primary breast tumors that metastasized to bone. Bioinformatics analysis identified genes that are differentially expressed in breast cancer bone metastases compared to primary mammary tumors. Results: ABCC5, an ATP-dependent transporter, was found to be overexpressed in breast cancer osseous metastases relative to primary mammary tumors. In addition, ABCC5 was significantly up-regulated in human and mouse breast cancer cell lines with high bone-metastatic potential. Stable knockdown of ABCC5 significant reduced bone metastatic burden and osteolytic bone destruction in mice. The decrease in osteolysis was further associated with diminished osteoclast numbers. Conclusions: Our data, for the first time, suggests that ABCC5 functions as a mediator of breast cancer skeletal metastasis. ABCC5 expression in breast cancer cells is important for the efficient bone resorption mediated by osteoclasts. Hence, ABCC5 may be a potential therapeutic target for breast cancer bone metastasis.
Project description:IKB Kinase beta (IKKB), a key component of the NFKB signalling pathway plays an important role in inflammation and cancer. Here we describe a previously unknown role of the IKKβ/FoxO3a axis in bone metastasis. We found that IKKβ was highly expressed in invasive human breast tumours and that levels of expression were elevated in bone metastasis. Overexpression of IKKβ in parental and bone-tropic human breast cancer cell-lines increased tumour volume, worsened cachexia, promoted osteolysis and increased mortality in adult mice whereas pharmacological inhibition and knockdown of IKKβ were inhibitory. Inhibition of IKKβ in breast cancer cell lines and bone cells stimulated bone formation and reduced tumour growth by a mechanism that was mediated in part, by cytoplasmic sequestering of FoxO3a independently of NFKB inhibition. We conclude that IKβ contributes significantly to the regulation of tumour growth and osteolysis in breast cancer by NFKB dependent and independent mechanisms.
Project description:Bone metastasis is an incurable complication of breast cancer. In advanced stages, patients with estrogen-positive tumors experience significantly higher incidence of bone metastasis compared to estrogen-negative patients. To investigate how estrogen-positive breast cancer cells communicate with bone microenvironmental cells, extracellular vesicles from bone metastatic MCF7BoM2 were purified and analyzed. We used GeneChip miRNA 4.1 Array to detail the miRNA expression in the extracellular vesicles from the bone metastatic MCF7BoM2 and its parental cell line MCF7, and identified the dysregulated miRNAs.