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1.
Breast Cancer Res Treat ; 165(3): 473-475, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28681172

ABSTRACT

PURPOSE: The Kennedy report into the actions of the disgraced Breast Surgeon, Paterson focussed on issues of informed consent for mastectomy, management of surgical margins and raised concerns about local recurrence rates and the increasing emphasis on cosmesis after mastectomy for breast cancer. This article assesses whether Kennedy's recommendations apply to the UK as a whole and how to address these issues. New GMC advice on consent and newer nonevidenced innovations in immediate reconstruction have altered the level of informed consent required. Patients deserve a better understanding of the issues of oncological versus cosmetic outcomes on which to base their decisions. Involvement of the whole multidisciplinary team including Oncologists is necessary in surgical planning. Failure to obtain clear microscopic margins at mastectomy leads to an increased local recurrence, yet has received little attention in the UK. Whereas, other countries have used surgical quality assurance audits to reduce local recurrence; local recurrence rates are not available and the extent of variation across the UK in margin involvement after surgery, its management and relationship to local recurrence needs auditing prospectively to reduce unnecessary morbidity. To reassure public, patients and the NHS management, an accreditation system with more rigour than NHSBSP QA and peer review is now required. Resource and efforts to support its introduction will be necessary from the Royal College of Surgeons and the Association of Breast Surgeons. New innovations require careful evaluation before their backdoor introduction to the NHS. Private Hospitals need to have the same standards imposed.


Subject(s)
Breast Neoplasms/surgery , Malpractice , Margins of Excision , Mastectomy/ethics , Mastectomy/standards , Quality Assurance, Health Care , Breast Neoplasms/pathology , Female , Humans
2.
Br J Surg ; 103(1): 81-7, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26768099

ABSTRACT

BACKGROUND: The aim was to determine long-term overall, breast cancer-specific and metastasis-free survival as well as axillary relapse rate from a pooled analysis of two randomized trials in women with operable breast cancer. These trials compared axillary node sampling (ANS), combined with axillary radiotherapy (AXRT) if the sampled nodes were involved, with axillary node clearance (ANC). METHODS: Data from two clinical trials at the Edinburgh Breast Unit that randomized patients between 1980 and 1995 were pooled. Long-term survival was analysed using Kaplan-Meier curves and Cox regression, with separate analyses for patients with node-positive (ANS + AXRT versus ANC) and node-negative (ANS versus ANC) disease. RESULTS: Of 855 women randomized, 799 were included in the present analysis after a median follow-up of 19·4 years. Some 301 patients (37·7 per cent) had node-positive disease. There was no evidence of a breast cancer survival advantage for ANS versus ANC in patients with node-negative disease (hazard ratio (HR) 0·88, 95 per cent c.i. 0·58 to 1·34; P = 0·557), or for ANS + AXRT versus ANC in those with node-positive breast cancer (HR 1·07, 0·77 to 1·50; P = 0·688). There was no metastasis-free survival advantage for ANS versus ANC in patients with node-negative tumours (HR 1·03, 0·70 to 1·51; P = 0·877), or ANS + AXRT versus ANC in those with node-positive disease (HR 1·03, 0·75 to 1·43; P = 0·847). Node-negative patients who underwent ANS had a higher risk of axillary recurrence than those who had ANC (HR 3·53, 1·29 to 9·63; P = 0·014). Similarly, among women with node-positive tumours, the risk of axillary recurrence was greater after ANS + AXRT than ANC (HR 2·64, 1·00 to 6·95; P = 0·049). CONCLUSION: Despite a higher rate of axillary recurrence with ANS combined with radiotherapy to the axilla, ANC did not improve overall, breast cancer-specific or metastasis-free survival. Axillary recurrence is thus not a satisfactory endpoint when comparing axillary treatments.


Subject(s)
Breast Neoplasms/radiotherapy , Carcinoma, Ductal, Breast/radiotherapy , Lymph Nodes/pathology , Mastectomy , Adult , Aged , Aged, 80 and over , Axilla , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Carcinoma, Ductal, Breast/mortality , Carcinoma, Ductal, Breast/pathology , Carcinoma, Ductal, Breast/surgery , Female , Follow-Up Studies , Humans , Mastectomy, Segmental , Middle Aged , Neoplasm Recurrence, Local , Radiotherapy, Adjuvant , Survival Analysis , Treatment Outcome
3.
Br J Surg ; 103(7): 830-8, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27171027

ABSTRACT

BACKGROUND: Completeness of excision is the most important factor influencing local recurrence after breast-conserving surgery (BCS). The aim of this case-control study was to determine factors influencing incomplete excision in patients undergoing BCS. METHODS: Women with invasive breast cancer treated by BCS between 1 June 2008 and 31 December 2009 were identified from a prospectively collected database in the Edinburgh Breast Unit. The maximum size of the tumour, measured microscopically, was compared with the size estimated before operation by mammography and ultrasound imaging. A multivariable analysis was performed to investigate factors associated with incomplete excision. RESULTS: The cohort comprised 311 women, of whom 193 (62·1 per cent) had a complete (CE group) and 118 (40·7 per cent) an incomplete (IE group) excision. Mammography underestimated tumour size in 75·0 per cent of the IE group compared with 40·7 per cent of the CE group (P < 0·001). Ultrasound imaging underestimated tumour size in 82·5 per cent of the IE group compared with 56·5 per cent of the CE group (P < 0·001). The risk of an incomplete excision was greater when mammography or ultrasonography underestimated pathological size: odds ratio (OR) 4·38 (95 per cent c.i. 2·59 to 7·41; P < 0·001) for mammography, and OR 3·64 (2·03 to 6·54; P < 0·001) for ultrasound imaging. For every 1-mm underestimation of size by mammography and ultrasonography, the relative odds of incomplete excision rose by 10 and 14 per cent respectively. CONCLUSION: Underestimation of tumour size by current imaging techniques is a major factor associated with incomplete excision in women undergoing BCS.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/surgery , Mastectomy, Segmental , Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/diagnostic imaging , Carcinoma, Intraductal, Noninfiltrating/pathology , Carcinoma, Intraductal, Noninfiltrating/surgery , Case-Control Studies , Female , Humans , Mammography , Margins of Excision , Middle Aged , Multivariate Analysis , Neoplasm, Residual , Ultrasonography, Mammary
4.
Ann Oncol ; 26(7): 1280-91, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26019189

ABSTRACT

Neoadjuvant systemic therapy (NAST) provides the unique opportunity to assess response to treatment after months rather than years of follow-up. However, significant variability exists in methods of pathologic assessment of response to NAST, and thus its interpretation for subsequent clinical decisions. Our international multidisciplinary working group was convened by the Breast International Group-North American Breast Cancer Group (BIG-NABCG) collaboration and tasked to recommend practical methods for standardized evaluation of the post-NAST surgical breast cancer specimen for clinical trials that promote accurate and reliable designation of pathologic complete response (pCR) and meaningful characterization of residual disease. Recommendations include multidisciplinary communication; clinical marking of the tumor site (clips); and radiologic, photographic, or pictorial imaging of the sliced specimen, to map the tissue sections and reconcile macroscopic and microscopic findings. The information required to define pCR (ypT0/is ypN0 or ypT0 yp N0), residual ypT and ypN stage using the current AJCC/UICC system, and the Residual Cancer Burden system were recommended for quantification of residual disease in clinical trials.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/pathology , Clinical Trials as Topic/standards , Neoadjuvant Therapy/standards , Neoplasm, Residual/pathology , Practice Guidelines as Topic , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant , Female , Humans , Neoplasm Staging , Neoplasm, Residual/drug therapy , Prognosis
5.
J Clin Microbiol ; 53(10): 3247-55, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26224846

ABSTRACT

Actinomycosis is a chronic infection caused by Actinomyces species characterized by abscess formation, tissue fibrosis, and draining sinuses. The spectrum of infections caused by Actinomyces species ranges from classical invasive actinomycosis to a less invasive form of superficial skin and soft tissue infection. We present a review detailing all Actinomyces species isolated from breast infections in NHS Lothian between 2005 and 2013, Actinomyces species isolated from breast infections referred to the United Kingdom Anaerobe Reference Unit between 1988 and 2014, and cases describing Actinomyces breast infections published in the medical literature since 1994. Actinomyces species are fastidious organisms which can be difficult to identify and are likely to be underascertained as a cause of breast infections. Due to improved diagnostic methods, they are increasingly associated with chronic, recurrent breast infections and may play a more significant role in these infections than has previously been appreciated.


Subject(s)
Actinomyces/classification , Actinomyces/isolation & purification , Actinomycosis/microbiology , Mastitis/microbiology , Actinomycosis/epidemiology , Adult , Female , Humans , Mastitis/epidemiology , Middle Aged , United Kingdom/epidemiology , Young Adult
6.
Br J Surg ; 102(8): 883-93, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25919321

ABSTRACT

BACKGROUND: MRI has been used increasingly in the diagnosis and management of women with invasive breast cancer. However, its usefulness in the preoperative assessment of ductal carcinoma in situ (DCIS) remains questionable. A meta-analysis was conducted to examine the effects of MRI on surgical treatment of DCIS by analysing studies comparing preoperative MRI with conventional preoperative assessment. METHODS: Using random-effects modelling, the proportion of women with various outcomes in the MRI versus no-MRI groups was estimated, and the odds ratio (OR) and adjusted OR (adjusted for study-level median age) for each model were calculated. RESULTS: Nine eligible studies were identified that included 1077 women with DCIS who had preoperative MRI and 2175 who did not. MRI significantly increased the odds of having initial mastectomy (OR 1·72, P = 0·012; adjusted OR 1·76, P = 0·010). There were no significant differences in the proportion of women with positive margins following breast-conserving surgery (BCS) in the MRI and no-MRI groups (OR 0·80, P = 0·059; adjusted OR 1·10, P = 0·716), nor in the necessity of reoperation for positive margins after BCS (OR 1·06, P = 0·759; adjusted OR 1·04, P = 0·844). Overall mastectomy rates did not differ significantly according to whether or not MRI was performed (OR 1·23, P = 0·340; adjusted OR 0·97, P = 0·881). CONCLUSION: Preoperative MRI in women with DCIS is not associated with improvement in surgical outcomes.


Subject(s)
Breast Neoplasms/surgery , Carcinoma, Ductal, Breast/surgery , Carcinoma, Intraductal, Noninfiltrating/surgery , Magnetic Resonance Imaging , Preoperative Care , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Female , Humans , Mastectomy , Mastectomy, Segmental
7.
Breast Cancer Res Treat ; 147(1): 211-9, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25104442

ABSTRACT

The phosphatidylinositol-3-kinase pathway plays an important role in proliferation, migration and survival in breast cancer and may play a role in resistance to endocrine therapy. Pathway activation occurs as a result of mutations in PIK3CA or loss of functional PTEN. Matched primary and recurrent samples from 120 breast cancer patients treated with endocrine therapy were profiled with a qPCR-based mutation assay covering eight mutational hotspots in PIK3CA. PTEN was assayed by immunohistochemistry. Samples were well characterized with respect to anatomic location of recurrence (metastatic nodal or local recurrence as opposed to contralateral or ipsilateral new primary cancers). In total, 43 % of patients had at least one PIK3CA mutation at diagnosis, and 41 % had a mutation at the time of recurrence. Only 8 % of patients with local recurrence, metastatic disease or progression on primary endocrine treatment changed their PIK3CA mutation status (four gains, two losses, total 76). The most common changes in PIK3CA mutation status were seen in patients who developed a new cancer either in the treated or contralateral breast (64 %, three gains, four losses, total 11). PIK3CA mutation status does not change in the majority of patients with breast cancer and the acquisition of mutations in PIK3CA is not responsible for the development of endocrine resistance. PTEN loss at diagnosis is associated with a significantly shorter time to progression compared with tumours in which PTEN was retained. These are the most comprehensive data currently available correlating PIK3CA status, site of recurrence and endocrine resistance.


Subject(s)
Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/genetics , Mutation/genetics , Neoplasm Recurrence, Local/genetics , Neoplasms, Hormone-Dependent/genetics , Phosphatidylinositol 3-Kinases/genetics , Adenocarcinoma/drug therapy , Adenocarcinoma/genetics , Adenocarcinoma/mortality , Adenocarcinoma/secondary , Adult , Aged , Aged, 80 and over , Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/drug therapy , Carcinoma, Ductal, Breast/genetics , Carcinoma, Ductal, Breast/mortality , Carcinoma, Ductal, Breast/secondary , Carcinoma, Intraductal, Noninfiltrating/drug therapy , Carcinoma, Intraductal, Noninfiltrating/genetics , Carcinoma, Intraductal, Noninfiltrating/mortality , Carcinoma, Intraductal, Noninfiltrating/secondary , Carcinoma, Lobular/drug therapy , Carcinoma, Lobular/genetics , Carcinoma, Lobular/mortality , Carcinoma, Lobular/secondary , Class I Phosphatidylinositol 3-Kinases , Cohort Studies , Disease Progression , Female , Follow-Up Studies , Humans , Middle Aged , Neoplasm Invasiveness , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Neoplasms, Hormone-Dependent/drug therapy , Neoplasms, Hormone-Dependent/mortality , Neoplasms, Hormone-Dependent/secondary , Neoplasms, Second Primary/drug therapy , Neoplasms, Second Primary/genetics , Neoplasms, Second Primary/mortality , Neoplasms, Second Primary/secondary , PTEN Phosphohydrolase/genetics , Phosphatidylinositol 3-Kinase/genetics , Prognosis , Survival Rate
8.
Breast Cancer Res Treat ; 165(3): 783-784, 2017 10.
Article in English | MEDLINE | ID: mdl-28698972
9.
Breast Cancer Res Treat ; 136(1): 161-8, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22976805

ABSTRACT

Glycogen synthase kinase 3ß (GSK3ß) is phosphorylated and inactivated by the phosphoinositide 3 kinase PI3K/Akt pathway. Activation of Akt phosphorylates GSK3ß preventing phosphorylation of cyclin D1 which leads to accumulation and nuclear localisation of cyclin D1, activation of CDK4/6 and cell cycle progression. The CCND1 gene found at chromosome 11q13 has been shown to be amplified in approximately 15 % of breast cancers. Cyclin D1, the product of the CCND1 gene, is one of the most commonly overexpressed proteins in breast cancer. Protein expression for GSK3ß, phosphorylated-GSK3ß (p-GSK3ß), cyclin D1 and gene expression of CCND1 were examined in tissue microarrays of 1,686 patients from the Edinburgh Breast Conservation Series. High GSK3ß expression was associated with reduced distant relapse-free survival (DRFS), while no association between p-GSK3ß and breast cancer-specific survival was seen. CCND1 amplification is also associated with poor DRFS. On the contrary, cyclin D1 overexpression is associated with an increase in DRFS. Multivariate analysis was performed. We suggest that analysis of both GSK3ß and cyclin D1 expressions can be considered as a marker of good prognosis in early breast cancer.


Subject(s)
Breast Neoplasms , Cyclin D1 , Gene Expression Regulation, Neoplastic , Glycogen Synthase Kinase 3 , Aged , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/therapy , Cyclin D1/genetics , Cyclin D1/metabolism , Disease-Free Survival , Female , Glycogen Synthase Kinase 3/genetics , Glycogen Synthase Kinase 3/metabolism , Glycogen Synthase Kinase 3 beta , Humans , Middle Aged , Phosphatidylinositol 3-Kinases/metabolism , Prognosis , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Tamoxifen/administration & dosage , Tissue Array Analysis , Treatment Outcome
10.
Pharmacogenomics J ; 12(1): 10-21, 2012 Feb.
Article in English | MEDLINE | ID: mdl-20697427

ABSTRACT

The study aim was to identify early (within 14 days) and late changes (by 3 months) in breast cancer gene expression profiles associated with neoadjuvant therapy with letrozole. RNA from sequential tumour biopsies in 54 patients was analyzed on microarrays; changes were determined by frequency, magnitude and significance analyses. Substantially more genes were changed at 3 months (1503) than at 14 days (237). Early changed genes were associated with cell cycle (downregulation), blood vessel development and extracellular matrix (upregulation); late changes included 'cellular metabolic process', 'generation of precursor metabolites and energy' (decreased) and 'cell adhesion' 'biological adhesion' (increased). A striking difference between the early and late changes was the general location of downregulated genes-nuclear structures at 14 days and mitochondria after 3 months. These changes in gene expression profiles provide a new and important database by which to understand molecular mechanisms of letrozole in breast cancers.


Subject(s)
Aromatase Inhibitors/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Nitriles/therapeutic use , Transcriptome , Triazoles/therapeutic use , Aromatase Inhibitors/pharmacology , Cluster Analysis , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Humans , Letrozole , Nitriles/pharmacology , Prospective Studies , Time Factors , Treatment Outcome , Triazoles/pharmacology
11.
Breast Cancer Res Treat ; 128(3): 725-34, 2011 Aug.
Article in English | MEDLINE | ID: mdl-20941539

ABSTRACT

mTOR plays a key role in tumor cell cycle control, proliferation, and survival. RAD001 (everolimus) is a novel macrolide that inhibits mTOR and thus downstream signaling pathways. 31 post-menopausal women with early breast cancer were given 5 mg RAD001 once daily for 14 days prior to surgery. Biopsies were taken at diagnosis and at surgery (post 14 days of treatment) and assessed for immunohistochemical changes in proliferation (Ki67), apoptosis (active caspase-3), p-AKT (s473), p-S6 (s235/236 and s240/244), p-mTOR (s2448), ER, and PR. Five patients did not complete the 2-week treatment period due to adverse events. All adverse events were grade 1 or 2 (NCIC-CTC scale). RAD001 treatment significantly decreased proliferation (geometric mean reduction 74% from baseline (p = 0.019)), particularly in HER-2 positive tumors. High Ki67 pre-treatment correlated with reduction in Ki67, an increase in apoptosis, a reduction in p-AKT (cytoplasmic) and reduction in p-mTOR following treatment. Nuclear expression of p-AKT was significantly reduced with treatment. Tumors that had a reduction in Ki67 with treatment exhibited a significant reduction in cytoplasmic p-AKT. p-S6 staining was significantly reduced independently of Ki67 (p < 0.001 for two sites of phosphorylation). RAD001 5 mg/daily is safe and tolerable in postmenopausal early breast cancer patients and inhibits the mTOR pathway and its downstream effectors, significantly reducing tumor cell proliferation. Tumors with high Ki67, high p-AKT, and HER-2 positivity may be more responsive to mTOR inhibition with RAD001. This is the first study to report results of RAD001 5 mg as a single agent in early breast cancer.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms , Sirolimus/analogs & derivatives , TOR Serine-Threonine Kinases/antagonists & inhibitors , Aged , Aged, 80 and over , Antineoplastic Agents/adverse effects , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Everolimus , Female , Humans , Ki-67 Antigen/metabolism , Middle Aged , Neoplasm Staging , Proto-Oncogene Proteins c-akt/metabolism , Receptor, ErbB-2/metabolism , Ribosomal Protein S6 Kinases/metabolism , Sirolimus/adverse effects , Sirolimus/therapeutic use
12.
Eur J Appl Physiol ; 111(11): 2763-73, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21409400

ABSTRACT

Duchenne muscular dystrophy (DMD) is caused by the absence of a functional dystrophin protein and is modeled by the mdx mouse. The mdx mouse suffers an early necrotic bout in the hind limb muscles lasting from approximately 4 to 7 weeks. The purpose of this investigation was to determine the extent to which dystrophin deficiency changed the proteome very early in the disease process. In order to accomplish this, proteins from gastrocnemius from 6-week-old C57 (n = 6) and mdx (n = 6) mice were labeled with fluorescent dye and subjected to two-dimensional differential in-gel electrophoresis (2D-DIGE). Resulting differentially expressed spots were excised and protein identity determined via MALDI-TOF followed by database searching using MASCOT. Proteins of the immediate energy system and glycolysis were generally down-regulated in mdx mice compared to C57 mice. Conversely, expression of proteins involved in the Kreb's cycle and electron transport chain were increased in dystrophin-deficient muscle compared to control. Expression of cytoskeletal components, including tubulins, vimentin, and collagen, were increased in mdx mice compared to C57 mice. Importantly, these changes are occurring at only 6 weeks of age and are caused by acute dystrophin deficiency rather than more chronic injury. These data may provide insight regarding early pathologic changes occurring in dystrophin-deficient skeletal muscle.


Subject(s)
Acute-Phase Proteins/metabolism , Acute-Phase Reaction/metabolism , Dystrophin/deficiency , Muscular Dystrophy, Duchenne/metabolism , Proteomics , Acute-Phase Proteins/analysis , Animals , Energy Metabolism/physiology , Glycolysis/physiology , Metabolic Detoxication, Phase I/physiology , Metabolic Networks and Pathways/physiology , Mice , Mice, Inbred C57BL , Mice, Inbred mdx , Muscle Proteins/analysis , Muscle Proteins/metabolism , Muscle, Skeletal/chemistry , Muscle, Skeletal/metabolism , Muscular Dystrophy, Duchenne/pathology , Muscular Dystrophy, Duchenne/physiopathology
13.
Lancet Oncol ; 16(3): e105, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25752559
14.
Eur J Surg Oncol ; 47(10): 2515-2520, 2021 10.
Article in English | MEDLINE | ID: mdl-34238642

ABSTRACT

Postmastectomy radiotherapy (PMRT) is accepted as the standard of care for women with early breast cancer with 4 or more involved axillary nodes. However the role of PMRT in women with 1-3 involved nodes remains controversial and guidelines vary. We present the arguments against advocating postmastectomy radiotherapy for all women with node positive breast cancer.


Subject(s)
Breast Neoplasms/pathology , Breast Neoplasms/radiotherapy , Neoplasm Recurrence, Local , Antineoplastic Agents/therapeutic use , Axilla , Breast Neoplasms/therapy , Chemotherapy, Adjuvant , Female , Humans , Lymphatic Metastasis , Mastectomy , Neoadjuvant Therapy , Neoplasm Micrometastasis , Neoplasm Recurrence, Local/prevention & control , Patient Selection , Postoperative Period , Practice Guidelines as Topic , Radiotherapy, Adjuvant/adverse effects , Survival Rate
15.
Eur Phys J E Soft Matter ; 31(2): 215-27, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20221665

ABSTRACT

This paper develops a rigorous analysis of the microtubule elastic deformations in terms of the torsional degrees of freedom using the helix-based cylindrical structure of this biopolymer. Methods of differential geometry and the theory of elasticity are employed in our analysis. We find equilibrium conditions and constitutive equations in the linear regime. We estimate the value of torsional rigidity for microtubules based on their structure and some experimentally known elastic properties. The paper concludes with the derivation of a bulk modulus formula for a microtubule in solution. Both the entropy change and the fluctuation of the twist angle are obtained.


Subject(s)
Microtubules/chemistry , Microtubules/ultrastructure , Models, Chemical , Models, Molecular , Computer Simulation , Elastic Modulus , Protein Conformation
16.
Br J Cancer ; 101(8): 1253-60, 2009 Oct 20.
Article in English | MEDLINE | ID: mdl-19755984

ABSTRACT

BACKGROUND: Acquired resistance to endocrine therapy in breast cancer is poorly understood. Characterisation of the molecular response to aromatase inhibitors in breast cancer tissue may provide important information regarding development of oestrogen hypersensitivity. METHODS: We examined the expression levels of nuclear receptor co-regulators, the orphan nuclear receptor liver receptor homologue-1 and HER-2/neu growth factor receptor using real-time RT-PCR before and after 13-16 weeks of primary medical treatment with the aromatase inhibitors anastrozole or letrozole. RESULTS: mRNA expression of the steroid receptor co-activator 1 (SRC-1) and peroxisome-proliferator-activated receptor gamma co-activator-1alpha (PGC-1alpha) was correlated (P=0.002), and both co-activators increased during treatment in the patient group as a whole (P=0.008 and P=0.032, respectively), as well as in the subgroup of patients achieving an objective treatment response (P=0.002 and P=0.006). Although we recorded no significant change in SRC-3/amplified in breast cancer 1 level, the expression correlated positively to the change of SRC-1 (P=0.002). Notably, we recorded an increase in HER-2/neu levels during therapy in the total patient group (18 out of 26; P=0.016), but in particular among responders (15 out of 21; P=0.008). CONCLUSION: Our results show an upregulation of co-activator mRNA and HER-2/neu during treatment with aromatase inhibitors. These mechanisms may represent an early adaption of the breast cancer cells to oestrogen deprivation in vivo.


Subject(s)
Aromatase Inhibitors/therapeutic use , Breast Neoplasms/drug therapy , Heat-Shock Proteins/genetics , Histone Acetyltransferases/genetics , Receptor, ErbB-2/genetics , Transcription Factors/genetics , Breast Neoplasms/metabolism , Female , Gene Expression Regulation, Neoplastic , Humans , Neoadjuvant Therapy , Nuclear Receptor Coactivator 1 , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , RNA, Messenger/analysis , Receptors, Cytoplasmic and Nuclear/genetics , Receptors, Estrogen/analysis
17.
Ann Oncol ; 20(5): 816-27, 2009 May.
Article in English | MEDLINE | ID: mdl-19153118

ABSTRACT

Anthracyclines are considered to be among the most active agents for the treatment of breast cancer. However, their use is limited by cumulative, dose-related cardiotoxicity. Such cardiotoxicity results in a permanent loss of cardiac myocytes and a progressive reduction in cardiac function following each subsequent dose of anthracycline. Initially, damage to the heart is subclinical; however, increasingly impaired cardiac function can result in cardiovascular symptoms, with serious cardiac injury resulting in chronic heart failure. Since the early detection and treatment of cardiotoxicity can reduce its clinical effects, it is important that oncologists are aware of these adverse effects and manage them appropriately. This review examines the risk factors for anthracycline-associated cardiotoxicity and offers recommendations on strategies to reduce the cardiotoxicity of anthracyclines in the management of patients with advanced breast cancer.


Subject(s)
Anthracyclines/adverse effects , Antibiotics, Antineoplastic/adverse effects , Breast Neoplasms/drug therapy , Heart Diseases/chemically induced , Breast Neoplasms/pathology , Dose-Response Relationship, Drug , Drug Monitoring , Female , Heart Diseases/pathology , Heart Diseases/prevention & control , Humans , Patient Selection , Practice Guidelines as Topic , Risk Assessment , Risk Factors
18.
Breast Cancer Res Treat ; 114(2): 211-21, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18409068

ABSTRACT

Early clinical trials of anticancer agents may be enriched by robust biomarkers of activity. Surrogate measures used in trials of cytotoxic agents, such as tumor size regression, may not be informative when investigating targeted agents that act principally to inhibit invasion or proliferation. This study aimed to determine the validity of invasion-related biomarkers of activity for AZD0530, a potent Src inhibitor currently in clinical development. Focal adhesion kinase (FAK) and paxillin are downstream phosphorylation substrates of Src and mediate tumor cell adhesion and invasiveness. These were therefore selected as biologically relevant markers of Src inhibition. Early breast cancer was chosen as a model as multiple samples can be collected during standard treatment and there is an intervening period in which experimental intervention can be applied. Tumor tissue was collected from diagnostic core biopsies and subsequent surgical tumor excision samples in 29 women with early breast cancer attending a single center. Protein levels were assessed quantitatively by Luminex and qualitatively by immunohistochemistry. AZD0530 inhibited tumor growth in a manner independent of dose and inhibited phosphorylation of FAK and paxillin in a dose-dependent manner in a Calu-6 xenograft model. In the clinical study, agreement of within-visit and also of between-visit measurements was high and the estimated number of patients required to detect a drug effect would be low enough to allow use of these markers as endpoints in future dose selection studies.


Subject(s)
Benzodioxoles/pharmacology , Breast Neoplasms/drug therapy , Focal Adhesion Kinase 1/metabolism , Lung Neoplasms/drug therapy , Paxillin/metabolism , Protein-Tyrosine Kinases/antagonists & inhibitors , Quinazolines/pharmacology , Xenograft Model Antitumor Assays , Animals , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , CSK Tyrosine-Protein Kinase , Feasibility Studies , Female , Humans , Immunoenzyme Techniques , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Phosphorylation/drug effects , Rats , Rats, Nude , Tumor Cells, Cultured , src-Family Kinases
19.
Breast Cancer Res Treat ; 114(3): 495-501, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18438705

ABSTRACT

INTRODUCTION: Changes in proliferation as measured by Ki67 occur within 14 days of starting treatment with an aromatase inhibitor and these changes have been shown to be predictors of long term outcome. This study aimed to compare changes in proliferation following 14 days of treatment with anastrozole and letrozole. METHODS: Two hundred and six women with 209 estrogen receptor (ER) positive operable breast cancers (three bilateral) were randomly allocated to receive either 14 days treatment with 2.5 mg of letrozole or 1 mg of anastrozole prior to surgery. Changes in expression of estrogen (ER) and progesterone receptors (PgR) as assessed by ALLRED scores and proliferation as assessed by Ki67 were analysed. The HER2 status of each tumour was also assessed using a combination of the Hercept test and FISH. RESULTS: Both letrozole and anastrozole reduced ER expression (ALLRED score) by a mean of 0.32 (0.20-0.44), P<0.001 and PgR fell by a mean of 2.54 (2.20-2.89) P<0.0001. Letrozole reduced proliferation from a geometric mean of 6.37% to 0.81%, P<0.0001 and anastrozole reduced proliferation from 5.81% to 0.77%, P<0.0001. There was no differences between drugs in the fall in ER, PgR or proliferation. Both letrozole and anastrozole produced significant falls in proliferation in both HER2 positive and HER2 negative cancers, all P<0.001. DISCUSSION: 14 days of both letrozole and anastrozole reduces proliferation, ER and PgR expression. No significant difference between these two drugs was identified.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Estrogen Receptor alpha/biosynthesis , Nitriles/therapeutic use , Triazoles/therapeutic use , Adult , Aged , Aged, 80 and over , Anastrozole , Antineoplastic Agents, Hormonal/therapeutic use , Aromatase Inhibitors/therapeutic use , Female , Gene Expression Regulation, Neoplastic , Humans , Ki-67 Antigen/biosynthesis , Letrozole , Middle Aged , Postmenopause , Receptors, Progesterone/biosynthesis , Treatment Outcome
20.
Eur J Cancer ; 44(3): 391-9, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18083023

ABSTRACT

Fulvestrant (Faslodex) is a pure anti-oestrogen that reduces markers of hormone sensitivity and proliferation in postmenopausal women with oestrogen-receptor (ER)-positive breast cancer. This randomised trial compared the effects on the tumours of a single dose of 750mg fulvestrant to those of daily tamoxifen (20mg) taken 14-16 days prior to surgery in 60 premenopausal women with ER-positive primary breast cancer. There were statistically significant falls in the expression of ER and Ki67 levels compared to the baseline with both drugs. Both drugs caused a decrease in PgR expression from baseline but this was only statistically significant with fulvestrant. No statistically significant differences were seen between the two treatment groups. Fulvestrant caused an increase in circulating levels of oestradiol, irrespective of the stage of the menstrual cycle at which patients commenced treatment. No major changes were seen in LH, FSH and progesterone levels with either drug. The most common adverse events with fulvestrant were headaches, hot flushes, nausea and disturbance of menses. Contrary to previous studies with fulvestrant 250mg, these findings suggest that at a dose of 750mg fulvestrant is effective at reducing the effects of oestrogen on ER-positive breast cancer in premenopausal women.


Subject(s)
Antineoplastic Agents, Hormonal/administration & dosage , Breast Neoplasms/drug therapy , Estradiol/analogs & derivatives , Neoplasms, Hormone-Dependent/drug therapy , Receptors, Estrogen/metabolism , Tamoxifen/administration & dosage , Adult , Antineoplastic Agents, Hormonal/adverse effects , Antineoplastic Agents, Hormonal/blood , Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Estradiol/administration & dosage , Estradiol/adverse effects , Estradiol/blood , Female , Fulvestrant , Humans , Injections, Intramuscular , Ki-67 Antigen/metabolism , Middle Aged , Neoplasms, Hormone-Dependent/metabolism , Premenopause/drug effects , Premenopause/metabolism , Receptors, Progesterone/metabolism , Tamoxifen/adverse effects , Tamoxifen/blood , Treatment Outcome
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