Ingunn Holen | The University of Sheffield (original) (raw)

Papers by Ingunn Holen

Research paper thumbnail of Expression pattern of the ADAMTS proteinases in human prostate cancer cell lines

European Urology Supplements, 2003

Research paper thumbnail of Synergistic effects of cytotoxic drugs and antiresorptive agents in vitro and in vivo

Breast Cancer Research, 2006

Research paper thumbnail of Expression and activity of ADAMTS-5 in synovium

European Journal of Biochemistry, 2001

Research paper thumbnail of Antitumor Effects of Doxorubicin Followed by Zoledronic Acid in a Mouse Model of Breast Cancer

JNCI Journal of the National Cancer Institute, 2008

Research paper thumbnail of Differential Effect of Doxorubicin and Zoledronic Acid on Intraosseous versus Extraosseous Breast Tumor Growth In vivo

Clinical Cancer Research, 2008

Purpose: Breast cancer patients with bone metastases are commonly treated with chemotherapeutic a... more Purpose: Breast cancer patients with bone metastases are commonly treated with chemotherapeutic agents such as doxorubicin and zoledronic acid to control their bone disease. Sequential administration of doxorubicin followed by zoledronic acid has been shown to increase tumor cell apoptosis in vitro. We have therefore investigated the antitumor effects of clinically relevant doses of these drugs in a mouse model of breast cancer bone metastasis. Experimental Design: MDA-MB-231/BO2 cells were injected via the tail vein into athymic mice. Tumor-induced osteolytic lesions were detected in all animals following X-ray analysis 18 days after tumor cell inoculation (day 18). Mice were administered saline, 100 μg/kg zoledronic acid, 2 mg/kg doxorubicin, doxorubicin and zoledronic acid simultaneously, or doxorubicin followed 24 h later by zoledronic acid. Doxorubicin-treated animals received a second injection on day 25. Tumor growth in the marrow cavity and on the outside surface of the bone...

Research paper thumbnail of Macrophages as potential targets for zoledronic acid outside the skeleton—evidence from in vitro and in vivo models

Cellular Oncology, 2013

Multiple cell types of the tumour microenvironment, including macrophages, contribute to the resp... more Multiple cell types of the tumour microenvironment, including macrophages, contribute to the response to cancer therapy. The anti-resorptive agent zoledronic acid (ZOL) has anti-tumour effects in vitro and in vivo, but it is not known to what extent macrophages are affected by this agent. We have therefore investigated the effects of ZOL on macrophages using a combination of in vitro and in vivo models. J774 macrophages were treated with ZOL in vitro, alone and in combination with doxorubicin (DOX), and the levels of apoptosis and necrosis determined. Uptake of zoledronic acid was assessed by detection of unprenylated Rap1a in J774 macrophages in vitro, in peritoneal macrophages and in macrophage populations isolated from subcutaneously implanted breast cancer xenografts following ZOL treatment in vivo. Exposure of J774 macrophages to 5 μM ZOL for 24 h caused a significant increase in the levels of uRap1A, and higher doses/longer exposure induced apoptotic cell death. DOX (10 nM/24 h) and ZOL (10 μM/4 h) given in sequence induced significantly increased levels of apoptotic cell death compared to single agents. Peritoneal macrophages and macrophage populations isolated from breast tumour xenografts had detectable levels of uRap1A 24 h following a single, clinically achievable dose of 100 μg/kg ZOL in vivo. We demonstrate that macrophages are sensitive to sequential administration of DOX and ZOL, and that both peritoneal and breast tumour associated macrophages rapidly take up ZOL in vivo. Our data support that macrophages may contribute to the anti-tumour effect of ZOL.

Research paper thumbnail of Evaluation of the molecular mechanisms for the sequence-dependent, synergistic anti-tumour effects of doxorubicin and zoledronic acid in breast cancer

Cancer Research, 2009

#2151 Background: Recent reports suggest that zoledronic acid (Zometa®) may have anti-tumour effe... more #2151 Background: Recent reports suggest that zoledronic acid (Zometa®) may have anti-tumour effects outside the skeleton. We have previously shown that administration of doxorubicin (dox) 24h prior to zoledronic acid (zol) is critical for the inhibition of growth of established breast tumours implanted subcutaneously and intra-osseously. Inhibition of tumour growth was associated with reduced tumour cell proliferation and increased apoptosis in vivo. This is the first report of the potential molecular mechanisms by which doxorubicin and zoledronic acid exert their sequence-specific anti-tumour effects. Materials and methods: MDA-MB-436-GFP cells were inoculated into the flank (n=10/group) or tibia (n=8/group) of female MF1 nude mice. Mice were treated 1x per week for 6 weeks with saline, 2mg/kg dox, 100μg/kg zol, dox and zol simultaneously, dox followed 24h later by zol, or zol followed 24h later by dox. Animals were sacrificed 24h following the final treatment and tumour RNA prep...

Research paper thumbnail of P2-01-20: Reduced Plakoglobin Expression Increases the Metastatic Potential of Breast Cancer Cells

Cancer Research, 2011

The majority of deaths from breast cancer are a result of metastases, however, little is understo... more The majority of deaths from breast cancer are a result of metastases, however, little is understood about the genetic alterations underlying their onset. A recent study of human breast cancer biopsies showed alterations of expression of 9 genes in primary tumours that had metastasized compared to benign tumours. Of these, plakoglobin was the most altered, with metastatic tumours showing a 3x decrease in expression compared to benign. Furthermore, expression of plakoglobin is reduced upon autocrine production of human growth hormone, which is associated with increased breast tumour cell invasion in vivo. Plakoglobin codes for the adhesion protein gamma catenin, an integral part of the cadherin-catenin complex involved in cell-to-cell adhesion. The aim of the current study is to investigate the effects of plakoglobin knockdown on cell proliferation, migration, adhesion and invasion in vitro and in vivo. The non-metastatic human breast cancer cell lines MCF7 and T47D that express high levels of plakoglobin and gamma-catenin were stably transfected with miRNA to two different regions of the plakoglobin gene, or scramble vector, to produce plakoglobin knockdown and controls for each cell line. Plakoglobin gene expression was monitored by qPCR and gamma-catenin expression by Western blot. Cell proliferation was assessed 24, 48, 72 and 96 hours post seeding; cell migration and invasion were measured over 24 and 48 hours using scratch and modified Boyden Chamber assays. Cell-cell adhesion was assessed by spheroid formation in agar matrix. For in vivo experiments, MCF7 plakoglobin knockdown and control cells were inoculated into the 5th and 10th mammary fat pads of 12-week old female balb/c mice (n=10 per group). Tumour growth was monitored by caliper measurements and local invasion was investigated 6 weeks after tumour inoculation on histological sections. Shedding of tumour cells into the blood stream and evidence of metastatic bone lesions was monitored by flow cytometry and μCT, respectively. Plakoglobin and gamma catenin expression were reduced by more than 80% in all knockdown cell lines used but were unaltered following transfection with the scrambled vector. Furthermore, knockdown of plakoglobin did not effect expression of its binding partner, e-cadherin. Reduced expression of plakoglobin resulted in a more than 3-fold increase in MCF7 and T47D cell proliferation in vitro (p in vivo (P plakoglobin knockdown cells showed a 6 - 15 fold increase in invasion through basement membrane (p plakoglobin increases the early pro-metastatic behaviour of cells including increased cell proliferation, migration and invasion. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-01-20.

Research paper thumbnail of Loss of plakoglobin promotes decreased cell-cell contact, increased invasion, and breast cancer cell dissemination in vivo

Breast Cancer Research, 2012

Research paper thumbnail of Zoledronic acid (ZOL) and letrozole (LET) induce synergistic levels of apoptosis in breast cancer cells

Research paper thumbnail of The differential anti-tumour effects of zoledronic acid in breast cancer – evidence for a role of the activin signaling pathway

Research paper thumbnail of Tumour macrophages as potential targets of bisphosphonates

Journal of Translational Medicine, 2011

Research paper thumbnail of Modulating Bone Marrow Hematopoietic Lineage Potential to Prevent Bone Metastasis in Breast Cancer

Cancer research, Jan 15, 2018

The presence of disseminated tumor cells in breast cancer patient bone marrow aspirates predicts ... more The presence of disseminated tumor cells in breast cancer patient bone marrow aspirates predicts decreased recurrence-free survival. Although it is appreciated that physiologic, pathologic, and therapeutic conditions impact hematopoiesis, it remains unclear whether targeting hematopoiesis presents opportunities for limiting bone metastasis. Using preclinical breast cancer models, we discovered that marrow from mice treated with the bisphosphonate zoledronic acid (ZA) are metastasis-suppressive. Specifically, ZA modulated hematopoietic myeloid/osteoclast progenitor cell (M/OCP) lineage potential to activate metastasis-suppressive activity. Granulocyte-colony stimulating factor (G-CSF) promoted ZA resistance by redirecting M/OCP differentiation. We identified M/OCP and bone marrow transcriptional programs associated with metastasis suppression and ZA resistance. Analysis of patient blood samples taken at randomization revealed that women with high-plasma G-CSF experienced significantl...

Research paper thumbnail of Chemotherapy resistance and stemness in mitotically quiescent human breast cancer cells identified by fluorescent dye retention

Clinical & Experimental Metastasis

Research paper thumbnail of Pharmaceutical Uses of Bisphosphonates

Research paper thumbnail of Peripheral tumour re-growth following combination therapy - role of the bone microenvironment

Research paper thumbnail of Blocking IL-1R signalling inhibits breast cancer growth and bone metastases by altering the tumour microenvironment

Research paper thumbnail of Meet Our Editorial Board Member

Current Protein & Peptide Science, 2015

Research paper thumbnail of Prostate Cancer Cells Preferentially Home to Osteoblast-rich Areas in the Early Stages of Bone Metastasis: Evidence From In Vivo Models

Journal of Bone and Mineral Research, 2014

Research paper thumbnail of Combination therapy inhibits development and progression of mammary tumours in immunocompetent mice

Breast Cancer Research and Treatment, 2012

Research paper thumbnail of Expression pattern of the ADAMTS proteinases in human prostate cancer cell lines

European Urology Supplements, 2003

Research paper thumbnail of Synergistic effects of cytotoxic drugs and antiresorptive agents in vitro and in vivo

Breast Cancer Research, 2006

Research paper thumbnail of Expression and activity of ADAMTS-5 in synovium

European Journal of Biochemistry, 2001

Research paper thumbnail of Antitumor Effects of Doxorubicin Followed by Zoledronic Acid in a Mouse Model of Breast Cancer

JNCI Journal of the National Cancer Institute, 2008

Research paper thumbnail of Differential Effect of Doxorubicin and Zoledronic Acid on Intraosseous versus Extraosseous Breast Tumor Growth In vivo

Clinical Cancer Research, 2008

Purpose: Breast cancer patients with bone metastases are commonly treated with chemotherapeutic a... more Purpose: Breast cancer patients with bone metastases are commonly treated with chemotherapeutic agents such as doxorubicin and zoledronic acid to control their bone disease. Sequential administration of doxorubicin followed by zoledronic acid has been shown to increase tumor cell apoptosis in vitro. We have therefore investigated the antitumor effects of clinically relevant doses of these drugs in a mouse model of breast cancer bone metastasis. Experimental Design: MDA-MB-231/BO2 cells were injected via the tail vein into athymic mice. Tumor-induced osteolytic lesions were detected in all animals following X-ray analysis 18 days after tumor cell inoculation (day 18). Mice were administered saline, 100 μg/kg zoledronic acid, 2 mg/kg doxorubicin, doxorubicin and zoledronic acid simultaneously, or doxorubicin followed 24 h later by zoledronic acid. Doxorubicin-treated animals received a second injection on day 25. Tumor growth in the marrow cavity and on the outside surface of the bone...

Research paper thumbnail of Macrophages as potential targets for zoledronic acid outside the skeleton—evidence from in vitro and in vivo models

Cellular Oncology, 2013

Multiple cell types of the tumour microenvironment, including macrophages, contribute to the resp... more Multiple cell types of the tumour microenvironment, including macrophages, contribute to the response to cancer therapy. The anti-resorptive agent zoledronic acid (ZOL) has anti-tumour effects in vitro and in vivo, but it is not known to what extent macrophages are affected by this agent. We have therefore investigated the effects of ZOL on macrophages using a combination of in vitro and in vivo models. J774 macrophages were treated with ZOL in vitro, alone and in combination with doxorubicin (DOX), and the levels of apoptosis and necrosis determined. Uptake of zoledronic acid was assessed by detection of unprenylated Rap1a in J774 macrophages in vitro, in peritoneal macrophages and in macrophage populations isolated from subcutaneously implanted breast cancer xenografts following ZOL treatment in vivo. Exposure of J774 macrophages to 5 μM ZOL for 24 h caused a significant increase in the levels of uRap1A, and higher doses/longer exposure induced apoptotic cell death. DOX (10 nM/24 h) and ZOL (10 μM/4 h) given in sequence induced significantly increased levels of apoptotic cell death compared to single agents. Peritoneal macrophages and macrophage populations isolated from breast tumour xenografts had detectable levels of uRap1A 24 h following a single, clinically achievable dose of 100 μg/kg ZOL in vivo. We demonstrate that macrophages are sensitive to sequential administration of DOX and ZOL, and that both peritoneal and breast tumour associated macrophages rapidly take up ZOL in vivo. Our data support that macrophages may contribute to the anti-tumour effect of ZOL.

Research paper thumbnail of Evaluation of the molecular mechanisms for the sequence-dependent, synergistic anti-tumour effects of doxorubicin and zoledronic acid in breast cancer

Cancer Research, 2009

#2151 Background: Recent reports suggest that zoledronic acid (Zometa®) may have anti-tumour effe... more #2151 Background: Recent reports suggest that zoledronic acid (Zometa®) may have anti-tumour effects outside the skeleton. We have previously shown that administration of doxorubicin (dox) 24h prior to zoledronic acid (zol) is critical for the inhibition of growth of established breast tumours implanted subcutaneously and intra-osseously. Inhibition of tumour growth was associated with reduced tumour cell proliferation and increased apoptosis in vivo. This is the first report of the potential molecular mechanisms by which doxorubicin and zoledronic acid exert their sequence-specific anti-tumour effects. Materials and methods: MDA-MB-436-GFP cells were inoculated into the flank (n=10/group) or tibia (n=8/group) of female MF1 nude mice. Mice were treated 1x per week for 6 weeks with saline, 2mg/kg dox, 100μg/kg zol, dox and zol simultaneously, dox followed 24h later by zol, or zol followed 24h later by dox. Animals were sacrificed 24h following the final treatment and tumour RNA prep...

Research paper thumbnail of P2-01-20: Reduced Plakoglobin Expression Increases the Metastatic Potential of Breast Cancer Cells

Cancer Research, 2011

The majority of deaths from breast cancer are a result of metastases, however, little is understo... more The majority of deaths from breast cancer are a result of metastases, however, little is understood about the genetic alterations underlying their onset. A recent study of human breast cancer biopsies showed alterations of expression of 9 genes in primary tumours that had metastasized compared to benign tumours. Of these, plakoglobin was the most altered, with metastatic tumours showing a 3x decrease in expression compared to benign. Furthermore, expression of plakoglobin is reduced upon autocrine production of human growth hormone, which is associated with increased breast tumour cell invasion in vivo. Plakoglobin codes for the adhesion protein gamma catenin, an integral part of the cadherin-catenin complex involved in cell-to-cell adhesion. The aim of the current study is to investigate the effects of plakoglobin knockdown on cell proliferation, migration, adhesion and invasion in vitro and in vivo. The non-metastatic human breast cancer cell lines MCF7 and T47D that express high levels of plakoglobin and gamma-catenin were stably transfected with miRNA to two different regions of the plakoglobin gene, or scramble vector, to produce plakoglobin knockdown and controls for each cell line. Plakoglobin gene expression was monitored by qPCR and gamma-catenin expression by Western blot. Cell proliferation was assessed 24, 48, 72 and 96 hours post seeding; cell migration and invasion were measured over 24 and 48 hours using scratch and modified Boyden Chamber assays. Cell-cell adhesion was assessed by spheroid formation in agar matrix. For in vivo experiments, MCF7 plakoglobin knockdown and control cells were inoculated into the 5th and 10th mammary fat pads of 12-week old female balb/c mice (n=10 per group). Tumour growth was monitored by caliper measurements and local invasion was investigated 6 weeks after tumour inoculation on histological sections. Shedding of tumour cells into the blood stream and evidence of metastatic bone lesions was monitored by flow cytometry and μCT, respectively. Plakoglobin and gamma catenin expression were reduced by more than 80% in all knockdown cell lines used but were unaltered following transfection with the scrambled vector. Furthermore, knockdown of plakoglobin did not effect expression of its binding partner, e-cadherin. Reduced expression of plakoglobin resulted in a more than 3-fold increase in MCF7 and T47D cell proliferation in vitro (p in vivo (P plakoglobin knockdown cells showed a 6 - 15 fold increase in invasion through basement membrane (p plakoglobin increases the early pro-metastatic behaviour of cells including increased cell proliferation, migration and invasion. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-01-20.

Research paper thumbnail of Loss of plakoglobin promotes decreased cell-cell contact, increased invasion, and breast cancer cell dissemination in vivo

Breast Cancer Research, 2012

Research paper thumbnail of Zoledronic acid (ZOL) and letrozole (LET) induce synergistic levels of apoptosis in breast cancer cells

Research paper thumbnail of The differential anti-tumour effects of zoledronic acid in breast cancer – evidence for a role of the activin signaling pathway

Research paper thumbnail of Tumour macrophages as potential targets of bisphosphonates

Journal of Translational Medicine, 2011

Research paper thumbnail of Modulating Bone Marrow Hematopoietic Lineage Potential to Prevent Bone Metastasis in Breast Cancer

Cancer research, Jan 15, 2018

The presence of disseminated tumor cells in breast cancer patient bone marrow aspirates predicts ... more The presence of disseminated tumor cells in breast cancer patient bone marrow aspirates predicts decreased recurrence-free survival. Although it is appreciated that physiologic, pathologic, and therapeutic conditions impact hematopoiesis, it remains unclear whether targeting hematopoiesis presents opportunities for limiting bone metastasis. Using preclinical breast cancer models, we discovered that marrow from mice treated with the bisphosphonate zoledronic acid (ZA) are metastasis-suppressive. Specifically, ZA modulated hematopoietic myeloid/osteoclast progenitor cell (M/OCP) lineage potential to activate metastasis-suppressive activity. Granulocyte-colony stimulating factor (G-CSF) promoted ZA resistance by redirecting M/OCP differentiation. We identified M/OCP and bone marrow transcriptional programs associated with metastasis suppression and ZA resistance. Analysis of patient blood samples taken at randomization revealed that women with high-plasma G-CSF experienced significantl...

Research paper thumbnail of Chemotherapy resistance and stemness in mitotically quiescent human breast cancer cells identified by fluorescent dye retention

Clinical & Experimental Metastasis

Research paper thumbnail of Pharmaceutical Uses of Bisphosphonates

Research paper thumbnail of Peripheral tumour re-growth following combination therapy - role of the bone microenvironment

Research paper thumbnail of Blocking IL-1R signalling inhibits breast cancer growth and bone metastases by altering the tumour microenvironment

Research paper thumbnail of Meet Our Editorial Board Member

Current Protein & Peptide Science, 2015

Research paper thumbnail of Prostate Cancer Cells Preferentially Home to Osteoblast-rich Areas in the Early Stages of Bone Metastasis: Evidence From In Vivo Models

Journal of Bone and Mineral Research, 2014

Research paper thumbnail of Combination therapy inhibits development and progression of mammary tumours in immunocompetent mice

Breast Cancer Research and Treatment, 2012