Joanne Bowen

University of Adelaide · School of Medical Sciences

Research interests

  • Interests
    pre-clinical rat models

Publications

  • 5.30
    Impact points
    Biomarkers of regimen-related mucosal injury.

    Rachel J Gibson, Joanne M Bowen

    Cancer treatment reviews. 06/2011; 37(6):487-93.

    Regimen-related mucosal toxicity is extremely common following cytotoxic chemotherapy and radiotherapy. The alimentary mucosa is particularly susceptible to injury and dysfunction, leading to a constellation of adverse side effects. Currently there is no "one fit" biomarker of such injury.... [more] Regimen-related mucosal toxicity is extremely common following cytotoxic chemotherapy and radiotherapy. The alimentary mucosa is particularly susceptible to injury and dysfunction, leading to a constellation of adverse side effects. Currently there is no "one fit" biomarker of such injury. A number of biomarkers have been investigated in the context of gastrointestinal diseases, which may prove useful in the oncology arena. Two of significant potential include citrulline and calprotectin, however more work is required to define the most appropriate settings for their use. Identification of a biomarker that is easily obtained, measured, and accurately indicates mucosal damage, would allow for improved patient diagnosis of toxicities and prompt appropriate intervention. In this review, we highlight the effectiveness of currently examined biomarkers and discuss future avenues for research in this exciting area.
  • 2.46
    Impact points
    Irinotecan-induced alterations in intestinal cell kinetics and extracellular matrix component expression in the dark agouti rat.

    Noor Al-Dasooqi, Joanne M Bowen, Rachel J Gibson, Richard M Logan, Andrea M Stringer, Dorothy M Keefe

    International journal of experimental pathology. 04/2011; 92(5):357-65.

    Chemotherapy-induced mucositis is characterized by damage of mucous membranes throughout the alimentary tract (AT). Extracellular matrix (ECM) components play a vital role in maintaining mucosal barrier integrity by regulating cellular apoptosis, proliferation and differentiation of overlying epithe... [more] Chemotherapy-induced mucositis is characterized by damage of mucous membranes throughout the alimentary tract (AT). Extracellular matrix (ECM) components play a vital role in maintaining mucosal barrier integrity by regulating cellular apoptosis, proliferation and differentiation of overlying epithelial cells. The aims of this study were to characterize the changes in epithelial cell kinetics and to investigate the expression of the ECM components in the gastrointestinal tract following irinotecan administration. Female dark agouti rats were treated with single 200 mg/kg dose irinotecan and killed at various time points (1, 6, 24, 48, 72, 96 and 14 h) after treatment. Ki67 immunostaining and TUNEL were used to assess proliferation and apoptosis, respectively, in the jejunum and colon. Masson trichrome staining and picro-sirius red staining were used to determine the level of collagen, and immunohistochemistry was used to further assess collagen IV, fibronectin and laminin 1 and 2 expression in these tissues. Irinotecan halved cellular proliferation in the jejunum and colon at 48 and 24 h, respectively, while apoptosis peaked at 6 h (P < 0.05). There was a substantial increase in total collagen deposits around crypts from 24 h in both regions. However, collagen IV expression decreased significantly in the crypt region in a delayed fashion (P < 0.05). Fibronectin expression decreased significantly in jejunum and colon from 6 to 24 h following treatment (P < 0.05). Irinotecan induced a significant alteration in epithelial cell kinetics in both the jejunum and colon, and this correlated with changes in ECM component expression. Changes in ECM expression may have a direct impact on the loss of mucosal layer integrity evident in chemotherapy-induced mucositis.
  • 6.70
    Impact points
    Noncardiac vascular toxicities of vascular endothelial growth factor inhibitors in advanced cancer: a review.

    Dorothy Keefe, Joanne Bowen, Rachel Gibson, Thean Tan, Meena Okera, Andrea Stringer

    The oncologist. 03/2011; 16(4):432-44.

    The introduction of molecularly targeted anticancer therapies has brought the promise of longer survival times for select patients with cancers previously considered untreatable. However, it has also brought new toxicities that require understanding and management, sometimes for long periods of time... [more] The introduction of molecularly targeted anticancer therapies has brought the promise of longer survival times for select patients with cancers previously considered untreatable. However, it has also brought new toxicities that require understanding and management, sometimes for long periods of time. Vascular endothelial growth factor inhibitors are associated with a broad range of adverse effects, with vascular toxicity being particularly serious. This review focuses on the current understanding of the pathophysiology and mechanisms of macrovascular toxicities (hypertension, hemorrhage, and thromboembolism), their incidence and severity, the current clinical management, and implications in the advanced cancer setting. Movement of these agents into the early disease setting will alter the impact of these toxicities. Search Strategy and Selection Criteria. Information for this review was collected by searching PubMed/Medline and American Society of Clinical Oncology abstract databases. The medical subject heading terms used included toxicity, hypertension, thromboembolism, hemorrhage, intestinal perforation, risk factors, pharmacokinetics, and metabolism, combined with free text search terms including, but not limited to, VEGF inhibitor*, bevacizumab, sunitinib, and sorafenib. Articles published in English before March 2010 were included, in addition to information from case reports and pharmaceutical agent package inserts.
  • 2.03
    Impact points
    Selection of housekeeping genes for gene expression studies in a rat model of irinotecan-induced mucositis.

    Noor Al-Dasooqi, Joanne M Bowen, Rachel J Gibson, Richard M Logan, Andrea M Stringer, Dorothy M Keefe

    Chemotherapy. 02/2011; 57(1):43-53.

    Mucositis is the term used to describe damage caused by chemotherapy to mucous membranes of the alimentary tract. RT-PCR has recently been utilised to determine the molecular events that occur in mucositis. As this method relies on the use of a validated endogenous control, this study aims to valida... [more] Mucositis is the term used to describe damage caused by chemotherapy to mucous membranes of the alimentary tract. RT-PCR has recently been utilised to determine the molecular events that occur in mucositis. As this method relies on the use of a validated endogenous control, this study aims to validate commonly used housekeeping genes in an irinotecan-induced mucositis model. Rats were administered irinotecan and sacrificed at different time points, in particular 1, 24, 72 and 144 h following treatment. Histopathological damage was assessed by haematoxylin and eosin staining. RT-PCR was used to evaluate the expression of 11 housekeeping genes. Expression stability was determined by the Normfinder program. Matrix metalloproteinase 2 was used as a target gene to validate the appropriateness of the top-ranking housekeeping gene. For normalisation to multiple housekeeping genes, the most stable combination across all time points in the jejunum was Ywhaz/UBC and in the colon UBC/β-actin. SDHA and GAPDH were the most variable genes in the jejunum and colon where they were 4.4 and 3.2 fold upregulated following irinotecan, respectively. For normalisation of irinotecan-induced mucositis gene expression studies, a combination of Ywhaz/UBC and UBC/β-actin should be used in the jejunum and colon, respectively. UBC is the most favourable if restricted to a single housekeeping gene across all time points.
  • 2.64
    Impact points
    Matrix metalloproteinases are possible mediators for the development of alimentary tract mucositis in the dark agouti rat.

    Noor Al-Dasooqi, Rachel J Gibson, Joanne M Bowen, Richard M Logan, Andrea M Stringer, Dorothy M Keefe

    Experimental biology and medicine (Maywood, N.J.). 10/2010; 235(10):1244-56.

    Alimentary tract (AT) mucositis is a serious and debilitating side-effect of cancer therapy primarily characterized by damage of the mucous membranes throughout the AT. It is well established that this damage is a result of up-regulation of stress response genes and pro-inflammatory cytokines. Matri... [more] Alimentary tract (AT) mucositis is a serious and debilitating side-effect of cancer therapy primarily characterized by damage of the mucous membranes throughout the AT. It is well established that this damage is a result of up-regulation of stress response genes and pro-inflammatory cytokines. Matrix metalloproteinases (MMPs) have been shown to function in several of the pathways known to be up-regulated in mucositis and play a key role in tissue injury and inflammation in many gastrointestinal disorders. This study aims to characterize the expression of multiple MMPs including MMP-1, -2, -3, -9 and -12 and their inhibitors, tissue inhibitor of metalloproteinase (TIMP)-1 and -2, in a rat model of irinotecan-induced mucositis. Dark agouti rats were administered a single 200 mg/kg intraperitoneal dose of irinotecan and killed at 1, 6, 24, 48, 72, 96 and 144 h following treatment. Hematoxylin and eosin staining, immunohistochemistry and realtime polymerase chain reaction were used to assess histopathological damage and MMP expression in the jejunum and colon. Marked histopathological evidence of mucositis was observed in the jejunum and colon as early as six hours following irinotecan treatment. A significant alteration in both gene expression and tissue levels of MMPs and TIMPs was noted following irinotecan. The increase in MMP-2, -3, -9 and -12 levels was associated with inflammatory infiltrate and maximum tissue damage. In contrast, MMP-1 expression correlated with tissue restitution. TIMP-1 and -2 levels were significantly altered in the jejunum following irinotecan. The augmentation in the expression profiles of MMPs and their inhibitors correlated with histopathological alterations observed in the tissue following irinotecan. This prompts the consideration of MMPs as possible mediators of chemotherapy-induced mucositis.
  • 2.53
    Impact points
    Pro-inflammatory cytokines play a key role in the development of radiotherapy-induced gastrointestinal mucositis.

    Zhi Yi Ong, Rachel J Gibson, Joanne M Bowen, Andrea M Stringer, Jocelyn M Darby, Richard M Logan, Ann Sj Yeoh, Dorothy M Keefe

    Radiation oncology (London, England). 03/2010; 5:22.

    Mucositis is a toxic side effect of anti-cancer treatments and is a major focus in cancer research. Pro-inflammatory cytokines have previously been implicated in the pathophysiology of chemotherapy-induced gastrointestinal mucositis. However, whether they play a key role in the development of radiot... [more] Mucositis is a toxic side effect of anti-cancer treatments and is a major focus in cancer research. Pro-inflammatory cytokines have previously been implicated in the pathophysiology of chemotherapy-induced gastrointestinal mucositis. However, whether they play a key role in the development of radiotherapy-induced gastrointestinal mucositis is still unknown. Therefore, the aim of the present study was to characterise the expression of pro-inflammatory cytokines in the gastrointestinal tract using a rat model of fractionated radiotherapy-induced toxicity. Thirty six female Dark Agouti rats were randomly assigned into groups and received 2.5 Gys abdominal radiotherapy three times a week over six weeks. Real time PCR was conducted to determine the relative change in mRNA expression of pro-inflammatory cytokines IL-1beta, IL-6 and TNF in the jejunum and colon. Protein expression of IL-1beta, IL-6 and TNF in the intestinal epithelium was investigated using qualitative immunohistochemistry. Radiotherapy-induced sub-acute damage was associated with significantly upregulated IL-1beta, IL-6 and TNF mRNA levels in the jejunum and colon. The majority of pro-inflammatory cytokine protein expression in the jejunum and colon exhibited minimal change following fractionated radiotherapy. Pro-inflammatory cytokines play a key role in radiotherapy-induced gastrointestinal mucositis in the sub-acute onset setting.
  • 3.24
    Impact points
    Kinetics and regional specificity of irinotecan-induced gene expression in the gastrointestinal tract.

    Joanne M Bowen, Anna Tsykin, Andrea M Stringer, Richard M Logan, Rachel J Gibson, Dorothy M K Keefe

    Toxicology. 02/2010; 269(1):1-12.

    Gastrointestinal toxicity remains a significant and dose-limiting complication of cancer treatment. While the pathophysiology is becoming clearer, considerable gaps in the knowledge remain surrounding the timing and site-specific gene changes which occur in response to insult. As such, this study ai... [more] Gastrointestinal toxicity remains a significant and dose-limiting complication of cancer treatment. While the pathophysiology is becoming clearer, considerable gaps in the knowledge remain surrounding the timing and site-specific gene changes which occur in response to insult. As such, this study aimed to assess gene expression profiles in a number of regions along the gastrointestinal tract following treatment with the chemotherapy agent, irinotecan, and correlate them with markers of cell death and tissue damage. Data analysis of microarray results found that genes involved in apoptosis, mitogen activated kinase (MAPK) signalling and inflammation were upregulated within 6h, while genes involved in cell proliferation, wound healing and blood vessel formation were upregulated at later time points up to 72 h. Cell death was significantly increased at 6 and 24h, and the stomach showed the lowest severity of overt tissue damage. Real time PCR of MAPK signalling pathway genes found that the jejunum and colon had significantly increased expression in a number of genes at 72 h, where as the stomach was unchanged. These results indicate that overall severity of tissue damage may be determined by precisely timed target gene responses specific to each region. Therapeutic targeting of key gene responses at the appropriate time point may prove to be effective for prevention of chemotherapy-induced gastrointestinal damage.
  • Pro-inflammatory cytokines play a key role in the development of radiotherapy-induced gastrointestinal mucositis

    Zhi Ong, Rachel Gibson, Joanne Bowen, Andrea Stringer, Jocelyn Darby, Richard Logan, Ann Yeoh, Dorothy Keefe

    Radiation Oncology. 01/2010;

    Abstract Background Mucositis is a toxic side effect of anti-cancer treatments and is a major focus in cancer research. Pro-inflammatory cytokines have previously been implicated in the pathophysiology of chemotherapy-induced gastrointestinal mucositis. However, whether they play a key role in the... [more] Abstract Background Mucositis is a toxic side effect of anti-cancer treatments and is a major focus in cancer research. Pro-inflammatory cytokines have previously been implicated in the pathophysiology of chemotherapy-induced gastrointestinal mucositis. However, whether they play a key role in the development of radiotherapy-induced gastrointestinal mucositis is still unknown. Therefore, the aim of the present study was to characterise the expression of pro-inflammatory cytokines in the gastrointestinal tract using a rat model of fractionated radiotherapy-induced toxicity. Methods Thirty six female Dark Agouti rats were randomly assigned into groups and received 2.5 Gys abdominal radiotherapy three times a week over six weeks. Real time PCR was conducted to determine the relative change in mRNA expression of pro-inflammatory cytokines IL-1β, IL-6 and TNF in the jejunum and colon. Protein expression of IL-1β, IL-6 and TNF in the intestinal epithelium was investigated using qualitative immunohistochemistry. Results Radiotherapy-induced sub-acute damage was associated with significantly upregulated IL-1β, IL-6 and TNF mRNA levels in the jejunum and colon. The majority of pro-inflammatory cytokine protein expression in the jejunum and colon exhibited minimal change following fractionated radiotherapy. Conclusions Pro-inflammatory cytokines play a key role in radiotherapy-induced gastrointestinal mucositis in the sub-acute onset setting.
  • 2.46
    Impact points
    Irinotecan-induced mucositis manifesting as diarrhoea corresponds with an amended intestinal flora and mucin profile.

    Andrea M Stringer, Rachel J Gibson, Joanne M Bowen, Richard M Logan, Kimberly Ashton, Ann S J Yeoh, Noor Al-Dasooqi, Dorothy M K Keefe

    International journal of experimental pathology. 10/2009; 90(5):489-99.

    Chemotherapy-induced diarrhoea is a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy. Irinotecan is linked with severe mucositis and diarrhoea, the mechanisms of which remain poorly understood. Bacterial beta-glucuronidase is thought to be involved in the metabolism ... [more] Chemotherapy-induced diarrhoea is a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy. Irinotecan is linked with severe mucositis and diarrhoea, the mechanisms of which remain poorly understood. Bacterial beta-glucuronidase is thought to be involved in the metabolism of irinotecan, implicating the intestinal flora. Intestinal mucins may also be implicated in the development of chemotherapy-induced diarrhoea. Rats were treated with 200 mg/kg of irinotecan and killed at 96, 120 and 144 h. The rats were monitored for diarrhoea. Pathology and immunohistochemical staining was performed. The samples were cultured and faecal DNA was analysed using real-time polymerase chain reaction. Severe diarrhoea was observed from 72 to 96 h. A decrease in body mass was also observed after treatment. Significant changes in goblet cell numbers (both complete and cavitated cells) were observed in the small and large intestines. Changes in MUC gene expression were observed in the small intestine only. Modifications were observed to the intestinal flora profile, especially Escherichia coli, and an increase in the expression of beta-glucuronidase was detected. In conclusion, irinotecan-induced diarrhoea may be caused by an increase in some beta-glucuronidase-producing bacteria, especially E. coli, exacerbating the toxicity of active metabolites. Accelerated mucous secretion and mucin release may also contribute to the delayed onset of diarrhoea.
  • 3.93
    Impact points
    HER2 targeted therapies for cancer and the gastrointestinal tract.

    Noor Al-Dasooqi, Rachel Gibson, Joanne Bowen, Dorothy Keefe

    Current drug targets. 07/2009; 10(6):537-42.

    HER2 (v-erb-b2 erythroblastic leukemia viral oncogene) is a member of the epidermal growth factor (EGF) receptor family of receptor tyrosine kinases. Since the discovery of a role for HER2 and other EGF receptors in the development and progression of cancer, they have become targets for a number of ... [more] HER2 (v-erb-b2 erythroblastic leukemia viral oncogene) is a member of the epidermal growth factor (EGF) receptor family of receptor tyrosine kinases. Since the discovery of a role for HER2 and other EGF receptors in the development and progression of cancer, they have become targets for a number of targeted anti-cancer drugs. These drugs have proven to be effective in treating and managing a range of cancers, however, recent observations in the clinic have suggested that their administration causes many toxicities, including gastrointestinal toxicity. Drugs with HER2 inhibitory activity fall into two categories; the monoclonal antibodies and small molecule tyrosine kinase inhibitors. Both of these drug classes have been shown to induce symptoms consistent with mucositis development; including nausea and vomiting, diarrhoea and abdominal pain. However, to date, limited studies have been carried out to justify the source of these toxicities. This review summarizes our current knowledge of the toxicities associated with commonly used HER2 targeted therapy drugs, the role of HER2 in cancer and the healthy gastrointestinal tract and the possible mechanisms by which drugs with HER2 inhibitory activity can induce gastrointestinal damage and possibly mucositis in patients.
  • 2.65
    Impact points
    Matrix metalloproteinases: key regulators in the pathogenesis of chemotherapy-induced mucositis?

    Noor Al-Dasooqi, Rachel Gibson, Joanne Bowen, Dorothy Keefe

    Cancer chemotherapy and pharmacology. 04/2009;

    Chemotherapy is an effective anticancer treatment; however, it induces mucositis in a wide range of patients. Mucositis is the term used to describe the damage caused by radiation and chemotherapy to mucous membranes of the alimentary tract. This damage causes pain and ulceration, vomiting, bloating... [more] Chemotherapy is an effective anticancer treatment; however, it induces mucositis in a wide range of patients. Mucositis is the term used to describe the damage caused by radiation and chemotherapy to mucous membranes of the alimentary tract. This damage causes pain and ulceration, vomiting, bloating and diarrhoea, depending on the area of the alimentary tract affected. Although treatment is available for a small subset of patients suffering from mucositis, the majority rely on pain relief as their only treatment option. Much progress has been made in recent years into understanding the pathobiology underlying the development of mucositis. It is well established that chemotherapy causes prominent small intestinal and colonic damage as a result of up-regulation of stress response genes and pro-inflammatory cytokines. However, better understanding of the mediators of this damage is still required in order to target appropriate treatment strategies. Possible mediators of mucositis which have not been well researched are the matrix metalloproteinases (MMPs). MMPs have been shown to function in several of the pathways which are known to be up-regulated in mucositis and contribute to tissue injury and inflammation in many pathological conditions. This prompts the consideration of MMPs as possibly being key mediators in mucositis development.
  • 3.99
    Impact points
    Chemotherapy-Induced Modifications to Gastrointestinal Microflora: Evidence and Implications of Change.

    Andrea Stringer, Rachel Gibson, Joanne Bowen, Dorothy Keefe

    Current drug metabolism. 02/2009; 10(1):79-83.

    Mucositis is a common side effect of chemotherapy which remains poorly understood. Despite advances in the understanding of oral and small intestinal mucositis over recent years, large intestinal mucositis, including diarrhoea, has not been well defined and the underlying mechanisms of the condition... [more] Mucositis is a common side effect of chemotherapy which remains poorly understood. Despite advances in the understanding of oral and small intestinal mucositis over recent years, large intestinal mucositis, including diarrhoea, has not been well defined and the underlying mechanisms of the condition are yet to be established. The majority of the literature available concerning large intestinal mucositis is based on clinical observations, with very little basic research existing. However, from the little research conducted, it is likely that the intestinal microflora play a role in the development of chemotherapy-induced mucositis. This review will explore the potentially important relationship between intestinal microflora and the subsequent development of chemotherapy-induced mucositis.
  • 2.64
    Impact points
    Gastrointestinal microflora and mucins may play a critical role in the development of 5-Fluorouracil-induced gastrointestinal mucositis.

    Andrea Stringer, Rachel J Gibson, Richard Logan, Joanne Marie Bowen, Ann SJ Yeoh, Juliette Hamilton, Dorothy Mk Keefe

    Experimental biology and medicine (Maywood, N.J.). 01/2009;

    5-Fluorouracil (5-FU) is a commonly used chemotherapy agent in clinical oncology practice. Two of its major side effects are mucositis and diarrhoea. The structure of mucins offers mucosal protection, and allows maintenance of intestinal flora by providing attachment sites and preventing bacterial o... [more] 5-Fluorouracil (5-FU) is a commonly used chemotherapy agent in clinical oncology practice. Two of its major side effects are mucositis and diarrhoea. The structure of mucins offers mucosal protection, and allows maintenance of intestinal flora by providing attachment sites and preventing bacterial overgrowth and/or penetration. The aim of this study was to investigate changes in mucin secretion and microflora following treatment with 5-FU. Female DA rats were given a single 150 mg/kg ip dose of 5-FU. Rats were killed at various time points after treatment. Control rats received no treatment. Jejunum, colon and faecal samples were collected. Standard microbiological culture techniques were used to identify bacteria, and real time PCR was used to quantify bacteria in faecal samples. Goblet cells and cavitated goblet cells (having undergone mucus exocytosis) were also counted. Statistical analysis was carried out using the Mann Whitney U-test, followed by Bonferroni correction. Following treatment with 5-FU, we showed decreases in Clostridium spp., Lactobacillus spp. and Streptococcus spp., and an increase in Escherichia spp. in the jejunum. In the colon, 5-FU caused decreases in Enterococcus spp., Lactobacillus spp. and Streptococcus spp. Real time PCR of faecal samples showed decreasing trends in Lactobacillus spp. and Bacteroides spp., and an increasing trend in E. coli. Significant increases (p<0.05) were seen in Clostridium spp. and Staphylococcus spp. at 24 h. Goblet cell numbers decreased significantly in the jejunum from 24-72 h, with a significant increase in the percentage of cavitated goblet cells. In conclusion, 5-FU treatment causes significant changes in intestinal flora and mucin secretion in rats. These changes could result in systemic effects, and in particular may contribute to the development of chemotherapy-induced mucositis.
  • 2.71
    Impact points
    Faecal microflora and beta-glucuronidase expression are altered in an irinotecan-induced diarrhoea model in rats.

    Andrea Stringer, Rachel Gibson, Richard Logan, Joanne Bowen, Ann Yeoh, Dorothy Keefe

    Cancer biology & therapy. 01/2009; 7(12).

    Objectives: Chemotherapy-induced diarrhoea (CID) is a well recognised side effect of cancer treatment. However, the pathophysiology behind this debilitating side effect remains unclear. Irinotecan causes cholinergic and delayed onset diarrhoea in patients, in which beta-glucuronidase produced by gut... [more] Objectives: Chemotherapy-induced diarrhoea (CID) is a well recognised side effect of cancer treatment. However, the pathophysiology behind this debilitating side effect remains unclear. Irinotecan causes cholinergic and delayed onset diarrhoea in patients, in which beta-glucuronidase produced by gut bacteria is thought to be involved. Results: Diarrhoea occurred, as expected, following irinotecan treatment. beta-glucuronidase expression increased in the jejunum and colon. Faecal flora changed quantitatively after treatment also, with increases in E. coli, Staphylococcus spp., and Clostridium spp. (all beta-glucuronidase producing), and decreases in Lactobacillus spp., Bifidobacterium spp. (both beneficial bacteria), and Bacteroides spp. (beta-glucuronidase producing, major component of intestinal flora). Methods: Rats were treated with 200 mg/kg irinotecan and killed at various time points up to 72 h. Rats were monitored for diarrhoea. Sections were stained for beta-glucuronidase expression, and faecal DNA was analysed using real time PCR. Conclusions: Irinotecan-induced diarrhoea may be caused by an increase in beta-glucuronidase producing bacteria. However, the increase in bacteria may also be caused by irinotecan, further exaggerating the toxicity of the drug, and emphasising the need for these specific bacteria to be therapeutically targeted for successful treatment regimens to be accomplished.
  • 2.65
    Impact points
    Irinotecan-induced mucositis is associated with changes in intestinal mucins.

    Andrea Stringer, Rachel Gibson, Richard Logan, Joanne Bowen, Ann Yeoh, Jessica Laurence, Dorothy Keefe

    Cancer chemotherapy and pharmacology. 12/2008;

    PURPOSE: Mucositis is a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy and radiotherapy. Irinotecan is used to treat a variety of solid tumours, through the inhibition of DNA topoisomerase I and is linked with severe mucositis and diarrhoea. Mucus production appear... [more] PURPOSE: Mucositis is a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy and radiotherapy. Irinotecan is used to treat a variety of solid tumours, through the inhibition of DNA topoisomerase I and is linked with severe mucositis and diarrhoea. Mucus production appears to be increased, which may contribute to the development of diarrhoea. METHODS: Dark agouti rats were treated with irinotecan, and tissues collected at several time points up to 72 h. Goblet cells and mucin secretion were investigated, as well as mucin expression (Muc2 and Muc4) and kruppel-like factor (Klf) 4 using immunohistochemistry in the gastrointestinal tract. Both goblet cells and cells positive for Muc expression were counted, and analysed statistically using the Mann-Whitney U test with Bonferroni correction. RESULTS: Goblet cells decreased significantly after irinotecan treatment. However, mucin secretion increased. Mucin expression changed significantly after treatment. Muc2 and Muc4 decreased significantly in the villi of the jejunum after treatment, Muc2 and Muc4 decreased significantly in the crypts. Muc2 decreased significantly in the colon. CONCLUSIONS: Irinotecan causes an increase in mucin secretion and a net decrease in mucin-producing goblet cells, and the expression of Muc2 and Muc4 in the gastrointestinal tract is altered following treatment. Increased mucin secretion is likely to be related to altered mucin expression, and may contribute to chemotherapy-induced diarrhoea.
  • 2.41
    Impact points
    Emerging drugs for chemotherapy-induced mucositis.

    Dorothy M Keefe, Stephen T Sonis, Joanne M Bowen

    Expert opinion on emerging drugs. 10/2008; 13(3):511-22.

    BACKGROUND: Chemotherapy-induced mucositis is an increasingly recognized problem in cancer management, preventing full doses of treatment being given, compromising cure rates and reducing quality of life. Symptoms include mouth pain and ulceration, esophagitis, abdominal pain, bloating, and diarrhea... [more] BACKGROUND: Chemotherapy-induced mucositis is an increasingly recognized problem in cancer management, preventing full doses of treatment being given, compromising cure rates and reducing quality of life. Symptoms include mouth pain and ulceration, esophagitis, abdominal pain, bloating, and diarrhea. It is associated with increased infections and occasional mortality, and its palliation is very expensive. The pathobiology of mucositis is complex, and agents that target mechanisms to prevent mucositis or accelerate healing are in high demand. OBJECTIVES: To review existing and potential treatments for chemotherapy-induced mucositis in the context of current knowledge of pathobiology. METHODS: We searched for mucositis of any region of the gastrointestinal tract using Medline, the Pharmaprojects database and listed patents. RESULTS/CONCLUSIONS: There are many agents in varying stages of development for chemotherapy-induced mucositis. The field is complicated by the question of whether treatments should be developed as drugs or as medical foods, and whether the burden of proof of efficacy and safety should be different.
  • 5.30
    Impact points
    Technological advances in mucositis research: New insights and new issues.

    Rachel J Gibson, Joanne M Bowen, Dorothy M K Keefe

    Cancer treatment reviews. 09/2008; 34(5):476-82.

    The last decade has seen a significant acceleration in the introduction of molecular tools used in cancer diagnosis and treatment. Driving factors have been the movement of advanced technologies from the laboratory to the clinic and the shift to a more genetically individualised patient approach. Wi... [more] The last decade has seen a significant acceleration in the introduction of molecular tools used in cancer diagnosis and treatment. Driving factors have been the movement of advanced technologies from the laboratory to the clinic and the shift to a more genetically individualised patient approach. With this has followed an increased ability to study the toxic side effects of cancer treatment, some of which are newly emerging, by utilising many of the same technologies. Mucositis research in particular has reached a golden period of investigation and understanding of the pathobiological mechanisms that contribute to the development of the condition. This paper has selected a few of the emerging technologies that are highly relevant to mucositis research to discuss in detail. These technologies include target therapies, toxicogenomics, nanomedicine, pharmacogenetics and pharmacogenomics, with a particular focus on microarray technology. These technologies are critical to discuss in the context of mucositis research not only because they are widely applicable to cutting edge research, but they also provide opportunities for further advances both in the laboratory and clinical setting. In addition, some of these technologies have the potential to be implemented immediately in the field of mucositis research.
  • 2.65
    Impact points
    Characterisation of mucosal changes in the alimentary tract following administration of irinotecan: implications for the pathobiology of mucositis.

    Richard M Logan, Rachel J Gibson, Joanne M Bowen, Andrea M Stringer, Stephen T Sonis, Dorothy M K Keefe

    Cancer chemotherapy and pharmacology. 07/2008; 62(1):33-41.

    PURPOSE: The pathobiology of alimentary tract (AT) mucositis is complex and there is limited information about the events which lead to the mucosal damage that occurs during cancer treatment. Various transcription factors and proinflammatory cytokines are thought to play important roles in pathogene... [more] PURPOSE: The pathobiology of alimentary tract (AT) mucositis is complex and there is limited information about the events which lead to the mucosal damage that occurs during cancer treatment. Various transcription factors and proinflammatory cytokines are thought to play important roles in pathogenesis of mucositis. The aim of this study was to determine the expression of nuclear factor-kappaB (NF-kappaB), tumor necrosis factor (TNF) and interleukins-1beta (IL-1beta) and -6 (IL-6) in the AT following the administration of the chemotherapeutic agent irinotecan. METHODS: Eighty-one female dark Agouti rats were assigned to either control or experimental groups according to a specific time point. Following administration of irinotecan, rats were monitored for the development of diarrhoea. The rats were killed at times ranging from 30 min to 72 h after administration of irinotecan. Oral mucosa, jejunum and colon were collected and standard immunohistochemical techniques were used to identify NF-kappaB, TNF, IL-1beta and IL-6 within the tissues. Sections were also stained with haematoxylin and eosin for histological examination. RESULTS: Irinotecan caused mild to moderate diarrhoea in a proportion of the rats that received the drug. Altered histological features of all tissues from rats administered irinotecan were observed which included epithelial atrophy in the oral mucosa, reduction of villus height and crypt length in the jejunum and a reduction in crypt length in the colon. Tissue staining for NF-kappaB, TNF and IL-1beta and IL-6 peaked at between 2 and 12 h in the tissues examined. CONCLUSIONS: This is the first study to demonstrate histological and immunohistochemical evidence of changes occurring concurrently in different sites of the AT following chemotherapy. The results of the study provide further evidence for the role of NF-kappaB and associated pro-inflammatory cytokines in the pathobiology of AT mucositis. The presence of these factors in tissues from different sites of the AT also suggests that there may be a common pathway along the entire AT causing mucositis following irinotecan administration.
  • 2.82
    Impact points
    Prevention and treatment of regimen-related mucosal toxicity.

    Joanne M Bowen

    Recent patents on anti-cancer drug discovery. 07/2008; 3(2):68-75.

    Current standard treatments for cancer are associated with major dose-limiting toxic effects on healthy tissue. The mucosal layers of the body are particularly sensitive to regimen-induced damage, with patients suffering many unpleasant and potentially life-threatening side-effects. In recent years,... [more] Current standard treatments for cancer are associated with major dose-limiting toxic effects on healthy tissue. The mucosal layers of the body are particularly sensitive to regimen-induced damage, with patients suffering many unpleasant and potentially life-threatening side-effects. In recent years, there has been an increase in the understanding of the pathobiology of regimen-related mucosal injury which has lead to a number of exciting inventions for its prevention and treatment being recently patented. Agents such as growth factors, cytokines, receptor agonists/antagonists and anti-inflammatory agents are among those in development in this emerging field. The complexity of mucosal injury poses a challenge for researchers, however rational targeting of intervention strategies to critical mechanisms will lead to further progress.
  • 3.07
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    Trastuzumab induces gastrointestinal side effects in HER2-overexpressing breast cancer patients.

    Noor Al-Dasooqi, Joanne Bowen, Rachel Gibson, Thomas Sullivan, Jude Lees, Dorothy Keefe

    Investigational new drugs. 07/2008;

    Purpose: To characterise the gastrointestinal toxicities associated with Trastuzumab administration in HER2-overexpressing breast cancer patients. Methods: All patients (n = 46) who received Trastuzumab as a single agent or in conjunction with conventional anti-cancer treatment within the Royal Adel... [more] Purpose: To characterise the gastrointestinal toxicities associated with Trastuzumab administration in HER2-overexpressing breast cancer patients. Methods: All patients (n = 46) who received Trastuzumab as a single agent or in conjunction with conventional anti-cancer treatment within the Royal Adelaide Hospital Cancer Centre from 2002-2007 were included in this study. A retrospective analysis of case-notes was conducted to investigate the toxicities associated with Trastuzumab. Results: Trastuzumab as a single agent induced toxicities following 22% of administrations. Gastrointestinal toxicities were observed following 12% of administrations and included nausea and vomiting, diarrhoea, abdominal pain and bloating. However, other prominent toxicities that were not related to the gastrointestinal tract were also observed including fatigue and lung symptoms (10.4%). Elderly patients (>/=60 years) and those with metastatic disease experienced the highest frequency of toxicity. Conclusion: Trastuzumab induces a range of gastrointestinal toxicities in HER2-overexpressing breast cancer patients. These toxicities are separate to those caused by concurrent chemotherapy and/or radiotherapy.
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