A Population of M2 Macrophages Associated With Bone Formation

We previously identified transient brown adipocyte-like cells associated with heterotopic ossification (HO). These ancillary cells support new vessel synthesis essential to bone formation. Recent studies have shown that the M2 macrophage contributes to tissue regeneration in a similar way. To further define the phenotype of these brown adipocyte-like cells they were isolated and characterized by single-cell RNAseq (scRNAseq). Analysis of the transcriptome and the presence of surface markers specific for macrophages suggest that these cells are M2 macrophages. To validate these findings, clodronate liposomes were delivered to the tissues during HO, and the results showed both a significant reduction in these macrophages as well as bone formation. These cells were isolated and shown in culture to polarize towards either M1 or M2 similar to other macrophages. To confirm that these are M2 macrophages, mice received lipopolysacheride (LPS), which induces proinflammation and M1 macrophages. The results showed a significant decrease in this specific population and bone formation, suggesting an essential role for M2 macrophages in the production of bone. To determine if these macrophages are specific to HO, we isolated these cells using fluorescence-activated cell sorting (FACS) from a bone defect model and subjected them to scRNAseq. Surprisingly, the macrophage populations overlapped between the two groups (HO-derived versus callus) suggesting that they may be essential ancillary cells for bone formation in general and not selective to HO. Of further note, their unique metabolism and lipogenic properties suggest the potential for unique cross talk between these cells and the newly forming bone.

A replicating stem-like cell that contributes to bone morphogenetic protein 2-induced heterotopic bone formation

Bone morphogenetic protein 2 (BMP2)‐induced heterotopic bone formation (HBF) starts synchronously from zero upon BMP2 induction, which is advantageous for lineage tracking. The studies reported here in GLAST‐Cre^Ert2:tdTomato red (TR)^floxSTOPflox mice during BMP2‐induced HBF show 78.8 ± 11.6% of chondrocytes and 86.5 ± 1.9% of osteoblasts are TR⁺ after approximately 1 week. Clustering after single‐cell RNAseq resulted in nine cell types, and analysis revealed one as a highly replicating stem‐like cell (RSC). Pseudotiming suggested that the RSC transitions to a mesenchymal stem‐like cell that simultaneously expresses multiple osteoblast and chondrocyte transcripts (chondro‐osseous progenitor [COP]). RSCs and COPs were isolated using flow cytometry for unique surface markers. Isolated RSCs (GLAST‐TR⁺ Hmmr⁺ Cd200⁻) and COPs (GLAST‐TR⁺ Cd200⁺ Hmmr⁻) were injected into the muscle of mice undergoing HBF. Approximately 9% of the cells in heterotopic bone (HB) in mice receiving RSCs were GLAST‐TR⁺, compared with less than 0.5% of the cells in mice receiving COPs, suggesting that RSCs are many times more potent than COPs. Analysis of donor‐derived TR⁺ RSCs isolated from the engrafted HB showed approximately 50% were COPs and 45% were other cells, presumably mature bone cells, confirming the early nature of the RSCs. We next isolated RSCs from these mice (approximately 300) and injected them into a second animal, with similar findings upon analysis of HBF. Unlike other methodology, single cell RNAseq has the ability to detect rare cell populations such as RSCs. The fact that RSCs can be injected into mice and differentiate suggests their potential utility for tissue regeneration.

Using behaviour change and implementation science to address low referral rates in oncology

Background

Patients undergoing surgery for bowel cancer now have a routine screening test to assess their genetic predisposition to this and other cancers (Lynch syndrome). A result indicating a high risk should trigger referral to a genetic clinic for diagnostic testing, information, and management. Appropriate management of Lynch syndrome lowers morbidity and mortality from cancer for patients and their family, but referral rates are low. The aim of this project was to increase referral rates for patients at high risk of Lynch syndrome at two Australian hospitals, using the Theoretical Domains Framework (TDF) Implementation approach.

Methods

Multidisciplinary teams at each hospital mapped the referral process and discussed barriers to referral. A 12-month retrospective audit measured baseline referral rates. The validated Influences on Patient Safety Behaviours Questionnaire was administered to evaluate barriers using the TDF. Results were discussed in focus groups and interviews, and interventions co-designed, guided by theory. Continuous monitoring audits assessed change in referral rates.

Results

Teams (n = 8, 11) at each hospital mapped referral processes. Baseline referral rates were 80% (4/5) from 71 screened patients and 8% (1/14) from 113 patients respectively. The questionnaire response rate was 51% (36/71). Most significant barrier domains were: ‘environmental context;’ ‘memory and decision making;’ ‘skills;’ and ‘beliefs about capabilities.’ Focus groups and interviews with 19 healthcare professionals confirmed these domains as significant. Fifteen interventions were proposed considering both emerging and theory-based results. Interventions included: clarification of pathology reports, education, introduction of e-referrals, and inclusion of genetic status in documentation.

Audits continued to December 2016 showing a change in pathology processes which increased the accuracy of screening. The referral rate remained low: 46% at Hospital A and 9% Hospital B. Results suggest patients who have their referral deferred for some reason are not referred later.

Conclusion

Lynch syndrome is typical of low incidence problems likely to overwhelm the system as genomic testing becomes mainstream. It is crucial for health researchers to test methods and define generalizable solutions to address this problem. Whilst our approach did not improve referrals, we have deepened our understanding of barriers to referral and approaches to low frequency conditions.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3653-1) contains supplementary material, which is available to authorized users.

Management of papillary lesions without atypia of the breast diagnosed on needle biopsy

BACKGROUND

Current surgical practice often leads to excision of all papillary lesions of the breast diagnosed on percutaneous biopsy. This study aims to identify a subset of patients with papillary lesions who may be able to avoid surgery.

METHODS

Between January 2000 and December 2015, 157 cases of papillary lesions with complete surgical excision pathology results were reviewed retrospectively to compare the clinical, imaging and pathology features. Of these, 50 patients with benign papillary lesions without atypia and 19 patients with benign papillary lesions with atypia on needle biopsy were analysed to determine the rate of upgrade to malignancy after surgery.

RESULTS

Of the 50 patients with benign papillary lesions without atypia on biopsy, two (4%) were upgraded to low grade ductal carcinoma in situ after surgical excision. Both these patients had suspicious features on imaging. Of the 19 patients with papillary lesions with atypia diagnosed on needle biopsy, eight (42%) were upgraded to malignancy after surgery. The differences between benign, atypical and malignant papillary lesions were further compared. Malignant lesions were more suspicious radiologically (P = 0.001), more likely to have architectural distortion (P = 0.001), more peripherally located (P = 0.001) and were larger in size (P = 0.01). Patients diagnosed with malignant lesions were also older (P = 0.001).

CONCLUSION

Younger patients diagnosed with small central benign papillary lesions without atypia on needle biopsy, and without suspicious imaging, may be managed conservatively with surveillance.

Histological analysis of surgical samples and a proposed scoring system for infections in intervertebral discs

Back pain remains one the most prevalent types of pain and disability worldwide. Infection is estimated to be the underlying cause in approximately 0.01% of patients. Despite recent evidence demonstrating prominent infection rates, a standardised algorithm for diagnosis of disc infection is lacking. Histopathological evaluation can aid in confirming inflammatory changes and also in identifying degenerative changes. Hence, standardising practice through a clear scoring system with regards to inflammation and degeneration may have some utility in the clinical setting. To our knowledge no such systems exist specifically for intervertebral disc infection. A literature review of current methods of scoring inflammation and degeneration in spine surgery and orthopaedic surgery was performed. Based on the current evidence, a scoring system for disc inflammatory and degenerative changes was proposed. We propose four domains for consideration: (1) granulation tissue, (2) dense fibrosis, (3) chronic inflammatory cells, and (4) neutrophil count. The non-standardised nature of diagnosing infections and degeneration in the spinal surgery literature means that this scoring system is currently of particular value. Based on a literature review, our proposed method for diagnosis incorporates a combination of histopathological criteria expected to increase diagnostic sensitivity in the setting of disc infection. Overall, scoring can be applied to surgically obtained material and integrated directly into routine pathological practice.

Achieving behaviour change for detection of Lynch syndrome using the Theoretical Domains Framework Implementation (TDFI) approach: a study protocol

BACKGROUND

Lynch syndrome is an inherited disorder associated with a range of cancers, and found in 2-5 % of colorectal cancers. Lynch syndrome is diagnosed through a combination of significant family and clinical history and pathology. The definitive diagnostic germline test requires formal patient consent after genetic counselling. If diagnosed early, carriers of Lynch syndrome can undergo increased surveillance for cancers, which in turn can prevent late stage cancers, optimise treatment and decrease mortality for themselves and their relatives. However, over the past decade, international studies have reported that only a small proportion of individuals with suspected Lynch syndrome were referred for genetic consultation and possible genetic testing. The aim of this project is to use behaviour change theory and implementation science approaches to increase the number and speed of healthcare professional referrals of colorectal cancer patients with a high-likelihood risk of Lynch syndrome to appropriate genetic counselling services.

METHODS

The six-step Theoretical Domains Framework Implementation (TDFI) approach will be used at two large, metropolitan hospitals treating colorectal cancer patients. Steps are: 1) form local multidisciplinary teams to map current referral processes; 2) identify target behaviours that may lead to increased referrals using discussion supported by a retrospective audit; 3) identify barriers to those behaviours using the validated Influences on Patient Safety Behaviours Questionnaire and TDFI guided focus groups; 4) co-design interventions to address barriers using focus groups; 5) co-implement interventions; and 6) evaluate intervention impact. Chi square analysis will be used to test the difference in the proportion of high-likelihood risk Lynch syndrome patients being referred for genetic testing before and after intervention implementation. A paired t-test will be used to assess the mean time from the pathology test results to referral for high-likelihood Lynch syndrome patients pre-post intervention. Run charts will be used to continuously monitor change in referrals over time, based on scheduled monthly audits.

DISCUSSION

This project is based on a tested and refined implementation strategy (TDFI approach). Enhancing the process of identifying and referring people at high-likelihood risk of Lynch syndrome for genetic counselling will improve outcomes for patients and their relatives, and potentially save public money.

Sensory nerve induced inflammation contributes to heterotopic ossification

Heterotopic ossification (HO), or bone formation in soft tissues, is often the result of traumatic injury. Much evidence has linked the release of BMPs (bone morphogenetic proteins) upon injury to this process. HO was once thought to be a rare occurrence, but recent statistics from the military suggest that as many as 60% of traumatic injuries, resulting from bomb blasts, have associated HO. In this study, we attempt to define the role of peripheral nerves in this process. Since BMP2 has been shown previously to induce release of the neuroinflammatory molecules, substance P (SP) and calcitonin gene related peptide (CGRP), from peripheral, sensory neurons, we examined this process in vivo. SP and CGRP are rapidly expressed upon delivery of BMP2 and remain elevated throughout bone formation. In animals lacking functional sensory neurons (TRPV1(-/-) ), BMP2-mediated increases in SP and CGRP were suppressed as compared to the normal animals, and HO was dramatically inhibited in these deficient mice, suggesting that neuroinflammation plays a functional role. Mast cells, known to be recruited by SP and CGRP, were elevated after BMP2 induction. These mast cells were localized to the nerve structures and underwent degranulation. When degranulation was inhibited using cromolyn, HO was again reduced significantly. Immunohistochemical analysis revealed nerves expressing the stem cell markers nanog and Klf4, as well as the osteoblast marker osterix, after BMP2 induction, in mice treated with cromolyn. The data collectively suggest that BMP2 can act directly on sensory neurons to induce neurogenic inflammation, resulting in nerve remodeling and the migration/release of osteogenic and other stem cells from the nerve. Further, blocking this process significantly reduces HO, suggesting that the stem cell population contributes to bone formation.

Heterotopic ossification has some nerve

Heterotopic ossification, defined as the formation of bone in abnormal anatomic locations, can be clinically insignificant or devastating and debilitating, depending on the site and duration of new bone formation. There are many causes of heterotopic ossification (HO), including soft tissue trauma, central nervous system injury, vasculopathies, arthropathies, and inheritance. One of the least understood components of HO is the interaction of the peripheral nervous system with the induction of this process. Recent work has shown that, upon traumatic injury, a cascade of events termed neurogenic inflammation is initiated, which involves the release of neuropeptides, such as substance P and calcitonin gene related peptide. Release of these peptides ultimately leads to the recruitment of activated platelets, mast cells, and neutrophils to the injury site. These cells appear to be involved with both remodeling of the nerve, as well as potentially recruiting additional cells from the bone marrow to the injury site. Further, sensory neurons stimulated at the injury site relay local information to the brain, which can then redirect neuroendocrine signaling in the hypothalamus towards repair of the injured site. While numerous studies have highlighted the important role of nerve-derived signals, both central and peripheral, in the regulation of normal bone remodeling of the skeleton,1 this review focuses on the role of the local, peripheral nerves in the formation of heterotopic bone. We concentrate on the manner in which local changes in bone morphogenetic protein (BMP) expression contribute to a cascade of events within the peripheral nerves, both sensory and sympathetic, in the immediate area of HO formation.

GSK3beta-cyclin D3-CUGBP1-eIF2 pathway in aging and in myotonic dystrophy

Epigenetic silencing of the cell cycle proteins is one of the major pathways of the inhibition of liver proliferation in old mice. We recently identified glycogen synthase 3beta, GSK3beta, as an enzyme which controls the epigenetic regulation of the liver proliferation via reduction of cyclin D3-cdk4. The elevation of cyclin D3 in livers of old mice leads to the accumulation of a transcriptional C/EBPalpha-HDAC1-Brm complex and translational CUGBP1-eIF2 complex. The accumulation of the CUGBP1-eIF2 increases translation of HDAC1 and C/EBPbeta in livers of old mice leading to formation of C/EBPbeta-HDAC1 complex which represses C/EBPbeta-dependent genes by interacting with their promoters. The translational CUGBP1-eIF2 complex also plays critical role in the regulation of biological processes in young livers and needs to be tightly regulated. Our recent paper showed that this complex is un-appropriately upregulated in skeletal muscle precursors of patients affected with multisystemic disease, Myotonic Dystrophy 2 (DM2) leading to translational elevation of several proteins. These data suggest that the age-specific translational dysfunctions might be involved in DM2 pathogenesis. Our data also suggest that the regulation of translation is conserved in liver and skeletal muscle. In this review, we discuss biological consequences of the age-associated alterations of translation in the liver and a possible role of the elevation of the CUGBP1-eIF2 complex in development of DM2 pathology.

Expression of RNA CCUG repeats dysregulates translation and degradation of proteins in myotonic dystrophy 2 patients

Myotonic dystrophy 2 (DM2) is a multisystem skeletal muscle disease caused by an expansion of tetranucleotide CCTG repeats, the transcription of which results in the accumulation of untranslated CCUG RNA. In this study, we report that CCUG repeats both bind to and misregulate the biological functions of cytoplasmic multiprotein complexes. Two CCUG-interacting complexes were subsequently purified and analyzed. A major component of one of the complexes was found to be the 20S catalytic core complex of the proteasome. The second complex was found to contain CUG triplet repeat RNA-binding protein 1 (CUGBP1) and the translation initiation factor eIF2. Consistent with the biological functions of the 20S proteasome and the CUGBP1-eIF2 complexes, the stability of short-lived proteins and the levels of the translational targets of CUGBP1 were shown to be elevated in DM2 myoblasts. We found that the overexpression of CCUG repeats in human myoblasts from unaffected patients, in C2C12 myoblasts, and in a DM2 mouse model alters protein translation and degradation, similar to the alterations observed in DM2 patients. Taken together, these findings show that RNA CCUG repeats misregulate protein turnover on both the levels of translation and proteasome-mediated protein degradation.

HDAC1 promotes liver proliferation in young mice via interactions with C/EBPbeta

HDAC1 (histone deacetylase 1) regulates a number of biological processes in cells. Our previous studies revealed that HDAC1 inhibits proliferation of the livers in old mice. We have surprisingly observed that HDAC1 is also increased in young livers proliferating after partial hepatectomy (PH) and in human liver tumors. Increased levels of HDAC1 after PH lead to its interaction with a member of the C/EBP family, C/EBPbeta, which is also elevated after PH. At early time points after PH, the HDAC1-C/EBPbeta complex binds to the C/EBPalpha promoter and represses expression of C/EBPalpha. A detailed analysis of the role of HDAC1 and C/EBPbeta proteins in the regulation of C/EBPalpha promoter showed that, whereas C/EBPbeta alone activates the promoter, HDAC1 represses the promoter in a C/EBPbeta-dependent manner. The inhibition of HDAC1 in the livers of young mice inhibits liver proliferation after PH, which is associated with high levels of C/EBPalpha. Consistent with the positive role of HDAC1-C/EBPbeta complexes in liver proliferation, we have found that the CUGBP1-HDAC1-C/EBPbeta pathway is activated in human tumor liver samples, suggesting that HDAC1-C/EBPbeta complexes are involved in the development of liver tumors. The causal role of the CUGBP1-HDAC1 pathway in liver proliferation was examined in CUGBP1 transgenic mice, which display high levels of the CUGBP1-eIF2 complex. We have demonstrated that elevation of the HDAC1-C/EBPbeta complexes in CUGBP1 transgenic mice reduces expression of C/EBPalpha and increases the rate of liver proliferation. Thus, these studies have identified a new pathway that promotes liver proliferation in young mice and might contribute to the malignant transformations in the liver.

HDAC1 cooperates with C/EBPalpha in the inhibition of liver proliferation in old mice

Epigenetic control of liver proliferation involves cooperation between transcription factors and chromatin-remodeling proteins. In this work, we found that the levels of HDAC1 (histone deacetylase 1) are increased in quiescent livers of old mice. The elevation of HDAC1 in liver is mediated by the RNA-binding protein CUGBP1. We found that the age-associated CUGBP1-eIF2 complex binds to the 5' region of HDAC1 mRNA and increases translation of HDAC1 in the liver. Further analyses showed that CUGBP1 also increases expression of HDAC1 in cultured cells, in the livers of CUGBP1 transgenic mice, and in the livers of mice injected with cyclin D3, which enhances the formation of the CUGBP1-eIF2 complex. In livers of old mice, HDAC1 interacts with the transcription factor C/EBPalpha and is recruited by this protein to E2F-dependent promoters as a component of high M(r) C/EBPalpha-Brm complexes. The recruitment of HDAC1 to c-Myc and FoxM1B promoters leads to deacetylation of histone H3 at Lys-9 on these E2F-dependent promoters. We show that HDAC1 is an important mediator of growth-inhibitory activity of C/EBPalpha and that small interfering RNA-mediated inhibition of HDAC1 reduces the ability of C/EBPalpha to inhibit cell proliferation. In addition, we have found that both elevation of HDAC1 and interaction of C/EBPalpha with HDAC1 are controlled by cyclin D3-dependent mechanisms. Treatment of old mice with growth hormone, which reduces cyclin D3 levels, leads to the reduction of the CUGBP1-eIF2 complex, normalization of HDAC1 levels, and inhibition of interactions of HDAC1 with C/EBPalpha-Brm complexes. Thus, our data demonstrate that translational elevation of HDAC1 in livers of old mice is involved in the assembly of high M(r) protein-protein complexes that inhibit liver proliferation.

Regulation of apoptotic and growth inhibitory activities of C/EBPalpha in different cell lines

C/EBPalpha is expressed in many tissues and inhibits cell growth. In this paper, we have examined mechanisms which regulate activities of C/EBPalpha in cell lines derived from different tissues. We found that C/EBPalpha possesses strong pro-apoptotic activity in NIH3T3 cells, while this activity is not detected in 3T3-L1, Hep3B2 and HEK293 cells. Micro-array data show that C/EBPalpha activates many genes of apoptosis signaling in NIH3T3 cells. One of these genes, ARL6IP5, is a direct target of C/EBPalpha and is a key mediator of the apoptosis. Using C/EBPalpha mutants which do not cause cell death; we have found that C/EBPalpha does not arrest proliferation of NIH3T3 cells. The lack of growth arrest in NIH3T3 cells correlates with the inhibition of p16INK4 and with low levels of cyclin D3. The limited growth inhibitory activity of C/EBPalpha is also observed in Hep3B2 cells which express low levels of cyclin D3. Elevation of cyclin D3 restores growth inhibitory activity of C/EBPalpha in NIH3T3 and in Hep3B2 cells. These data show that apoptotic and growth inhibitory activities of C/EBPalpha are differentially regulated in different cells and that cooperation of cyclin D3 and C/EBPalpha is required for the inhibition of proliferation.

Growth hormone corrects proliferation and transcription of phosphoenolpyruvate carboxykinase in livers of old mice via elimination of CCAAT/enhancer-binding protein alpha-Brm complex

Growth hormone (GH), which is reduced with age, corrects the impaired proliferative capacity of livers of old animals. In this paper, we present a mechanism by which GH eliminates age-dependent negative control of proliferation and increases transcription of liver-specific genes in livers of old mice. The reduced proliferative capacities of the liver of old animals are associated with the CCAAT/enhancer-binding protein alpha (C/EBPalpha)-Brm complex, which inhibits E2F-dependent promoters. We found that a sequestration of C/EBPalpha into complexes with Brm leads to a weak interaction of C/EBPalpha with promoters of liver-specific genes, expression of which is reduced in old animals. Injection of either GH or the regulator of the amplitude of endogenous GH release, ghrelin, reduces the C/EBPalpha-Brm complex in livers of old mice, leading to a derepression of E2F targets, to increased interactions of C/EBPalpha with promoters of liver-specific genes, and to correction of their expression. GH-dependent elimination of the complex is mediated by the inhibition of cyclin D3-CDK4 activity and by elevation of a phosphatase, protein phosphatase 2A, which dephosphorylates C/EBPalpha and dissociates the complex.

Intraoperative imprint cytology of sentinel lymph nodes in breast cancer: initial experience and lessons learnt in establishing a new practice

AIMS

The initial 18 months experience of performing intraoperative imprint cytology for patients with breast cancer undergoing sentinel lymph node biopsy is described for a single institution. The learning process is compared with published results from institutions with many years of experience in order to assess progress in reaching those ideal results, and the methodology used by these institutions is reviewed.

METHODS

A retrospective review was undertaken of the intraoperative imprint cytology results from 103 patients with breast cancer (yielding a total of 170 lymph nodes) who underwent imprint cytology of their sentinel lymph node. The intraoperative imprint cytology results were compared with the final histopathological results. Details regarding the primary tumour characteristics and metastatic deposit size were recorded.

RESULTS

The sensitivity for imprint cytology was 31.1%, with a specificity of 100% and overall accuracy of 77.8%. The sensitivity for detecting macrometastases (>2 mm diameter) was 61.9% and the sensitivity for micrometastases (<2 mm diameter) and including isolated tumour cells was 4.2%.

CONCLUSIONS

The differences in sensitivity in comparison with many studies in the literature are multifactorial, and include technical aspects, such as the methodology used in the final histopathological and intraoperative evaluation of the sentinel lymph nodes, interpretative difficulties, and much lower case numbers. Furthermore, these numbers represent early experience and methods to improve sensitivity and overall accuracy are detailed in this paper.

Histiocytoid change in breast carcinoma: a report of 3 cases with an unusual cytomorphologic pattern of apocrine change

BACKGROUND

Breast carcinomas composed predominantly or exclusively of cells with foamy and/or granular cytoplasm have been termed histiocytoid breast carcinoma.

CASES

Three cases of HBC had fine needle aspirates that were moderately cellular and composed of cells with abundant foamy and/or granular cytoplasm, arranged in loosely cohesive groups and dispersed singly. The cells showed subtle cytologic atypia, including nuclear hyperchromasia and slightly irregular nuclear outlines. Definitive cytologic diagnosis was not possible in the 3 cases, and they were reported as "suspicious for malignancy." Core biopsies of 2 cases showed a typical Indian file pattern of invasive lobular carcinoma, while the third case was composed of sheets of discohesive histiocytoid cells admixed with a prominent lymphoid infiltrate. All 3 cases were E-cadherin negative, confirming their lobular nature.

CONCLUSION

HBC represents an unusual morphologic pattern of apocrine change that may be seen in lobular and ductal breast carcinomas. Recognition of these lesions is vital in that they may be mistaken for a variety of other entities composed of foamy/granular cells; some of those entities have vastly different implications for treatment and prognosis.

Age-specific CUGBP1-eIF2 complex increases translation of CCAAT/enhancer-binding protein beta in old liver

The RNA-binding protein CUGBP1 regulates translation of proteins in a variety of biological processes. In this study, we show that aging liver increases CUGBP1 translational activities by induction of a high molecular weight protein-protein complex of CUGBP1. The complex contains CUGBP1, subunits alpha, beta, and gamma of the initiation translation factor eIF2, and four proteins of the endoplasmic reticulum, eR90, CRT, eR60, and Grp78. The induction of the CUGBP1-eIF2 complex in old livers is associated with the elevation of protein levels of CUGBP1 and with the hyper-phosphorylation of CUGBP1 by a cyclin D3-cdk4 kinase, activity of which is increased with age. We have examined the role of the elevation of CUGBP1 and the role of cyclin D3-cdk4-mediated phosphorylation of CUGBP1 in the formation of the CUGBP1-eIF2 complex by using CUGBP1 transgenic mice and young animals expressing high levels of cyclin D3 after injection with cyclin D3 plasmid. These studies showed that both the increased levels of CUGBP1 and cdk4-mediated hyper-phosphorylation of CUGBP1 are involved in the age-associated induction of the CUGBP1-eIF2 complex. The CUGBP1-eIF2 complex is bound to C/EBPbeta mRNA in the liver of old animals, and this binding correlates with the increased amounts of liver-enriched activator protein and liver-enriched inhibitory protein. Consistent with these observations, the purified CUGBP1-eIF2 complex binds to the 5' region of C/EBPbeta mRNA and significantly increases translation of the three isoforms of C/EBPbeta in a cell-free translation system, in cultured cells, and in the liver. Thus, these studies demonstrated that age-mediated induction of the CUGBP1-eIF2 complex changes translation of C/EBPbeta in old livers.

A risk index for early node-negative breast cancer

BACKGROUND

This study compared the application of the St Gallen 2001 classification with a risk index developed at the New South Wales Breast Cancer Institute (BCI Index) for women with node-negative breast cancer treated without adjuvant systemic therapy.

METHODS

The BCI risk categories were constructed by identifying combinations of prognostic indicators that produced homogeneous low-, intermediate- and high-risk groups using the same variables as in the St Gallen classification.

RESULTS

The BCI low-risk category consisted of women aged 35 years or more with a grade 1 oestrogen receptor (ER)-positive tumour 20 mm or less in diameter, or with a grade 2 ER-positive tumour of 15 mm or less. This category constituted 40.1 per cent of patients, with a 10-year distant relapse-free survival (DRFS) rate of 97.2 per cent. The BCI intermediate-risk category included women aged 35 years or more with a grade 2 ER-positive tumour of diameter 16-20 mm, or a grade 1 or 2 ER-negative tumour measuring 15 mm or less, and comprised 12.1 per cent of the women, with a 10-year DRFS rate of 88 per cent. The high-risk category comprised 47.7 per cent of women, with a 10-year DRFS rate of 68.4 per cent.

CONCLUSION

If confirmed in other data sets, the BCI Index may be used to identify women at low risk of distant relapse (2.8 per cent at 10 years) who are unlikely to benefit from adjuvant systemic therapy, and women at intermediate risk of distant relapse (12 per cent at 10 years) in whom the benefit of adjuvant systemic therapy is small.

Cyclin D3 maintains growth-inhibitory activity of C/EBPalpha by stabilizing C/EBPalpha-cdk2 and C/EBPalpha-Brm complexes

C/EBPalpha arrests proliferation of young livers by inhibition of cdk2. In old mice, C/EBPalpha inhibits growth by repression of E2F-dependent promoters through the C/EBPalpha-Brm complex. In this paper, we show that cyclin D3-cdk4/cdk6 supports the ability of C/EBPalpha to inhibit liver proliferation in both age groups. Although cyclin D3-cdk4/cdk6 kinases are involved in the promotion of growth, they are expressed in terminally differentiated cells, suggesting that they have additional functions in these settings. We demonstrate that C/EBPalpha represents a target for phosphorylation by cyclin D3-cdk4/cdk6 complexes in differentiated liver cells and in differentiated adipocytes. Cyclin D3-cdk4/cdk6 specifically phosphorylate C/EBPalpha at Ser193 in vitro and in the liver and support growth-inhibitory C/EBPalpha-cdk2 and C/EBPalpha-Brm complexes. We found that cyclin D3 is increased in old livers and activates cdk4/cdk6, resulting in stabilization of the C/EBPalpha-Brm complex. Old livers fail to reduce the activity of cyclin D3-cdk4/cdk6 after partial hepatectomy, leading to high levels of C/EBPalpha-Brm complexes after partial hepatectomy, which correlate with weak proliferation. We examined the role of cyclin D3 in the stabilization of C/EBPalpha-cdk2 and C/EBPalpha-Brm by using 3T3-L1 differentiated cells. In these cells, cyclin D3 is increased during differentiation and phosphorylates C/EBPalpha at Ser193, leading to the formation of growth-inhibitory C/EBPalpha-cdk2 and C/EBPalpha-Brm complexes. The inhibition of cyclin D3 blocks the formation of these complexes. Thus, these studies provide a new function of cyclin D3, which is to support the growth-inhibitory activity of C/EBPalpha.

Nipple aspiration and ductal lavage in women with a germline BRCA1 or BRCA2 mutation

Introduction

The aim of this study was to collect serial samples of nipple aspirate (NA) and ductal lavage (DL) fluid from women with germline BRCA1/2 mutations in order to create a biorepository for use in identifying biomarkers of breast cancer risk.

Methods

Between March 2003 and February 2005, 52 women with germline BRCA1 or BRCA2 mutations (median age 43 years, range 27 to 65 years) were scheduled for six-monthly NA, DL and venesection. DL was attempted for all NA fluid-yielding (FY) and any non-FY ducts that could be located at each visit.

Results

Twenty-seven (52%) women were postmenopausal, predominantly (19/27) from risk reducing bilateral salpingo-oophorectomy (BSO). FY ducts were identified in 60% of all women, 76% of premenopausal women versus 44% of postmenopausal (P = 0.026). Eighty-five percent of women had successful DL. Success was most likely in women with FY ducts (FY 94% versus non-FY 71% (P = 0.049). DL samples were more likely to be cellular if collected from FY ducts (FY 68% versus non-FY 43%; P = 0.037). Total cell counts were associated with FY status (FY median cell count 30,996, range 0 to >1,000,000 versus non-FY median cell count 0, range 0 to 173,577; P = 0.002). Four women (8%) had ducts with severe atypia with or without additional ducts with mild epithelial atypia; seven others had ducts with mild atypia alone (11/52 (21%) in total). Median total cell count was greater from ducts with atypia (105,870, range 1920 to >1,000,000) than those with no atypia (174, 0 to >1,000,000; P ≤ 0.001).

Conclusion

It is feasible to collect serial NA and DL samples from women at high genetic risk of breast cancer, and we are creating a unique, prospective collection of ductal samples that have the potential to be used for discovery of biomarkers of breast cancer risk and evaluate the ongoing effects of risk reducing BSO. DL cellular atypia was not predictive of a current breast cancer and longer follow up is needed to determine whether atypia is an additional marker of future breast cancer risk in this population already at high genetic risk of breast cancer.

A thermochromic dispersive electrode can measure the underlying skin temperature and prevent burns during radiofrequency ablation

Evaluation of a thermochromic dispersive electrode.

INTRODUCTION

Burns at the dispersive electrode are serious complications of diathermy and radiofrequency (RF) ablation procedures. We aimed to create a new methodology to reduce the incidence of dispersive electrode related skin burns. We hypothesized that a dispersive electrode incorporating a thermochromic liquid crystal (TLC) layer could accurately measure underlying skin temperatures and help prevent burns.

METHODS AND RESULTS

The TLC electrode was compared with a standard dispersive electrode in 12 male sheep. RF current was delivered with the dispersive electrode fully applied or partially detached to simulate different clinical scenarios. The temperature of the TLC layer, calculated from the hue (color) every 15 seconds, was compared with fluoroptic skin temperature probes. TLC electrodes with a temperature range of 45-58 degrees C were used in six sheep to assess the correlation of TLC temperature distribution with skin temperature and burns. TLC electrodes with a temperature range of 40-50 degrees C were used in another 6 sheep to simulate clinical conditions in which the ablation was stopped if the TLC temperature was >42 degrees C. The TLC measured temperatures correlated well with fluoroptic probes at the skin surface (r=0.94+/-0.05, mean of the absolute difference in temperature difference 0.9+/-0.58 degrees C). Ablations with partial application of standard dispersive electrodes consistently caused skin burns. There were no burns under the TLC electrode when ablations were ceased for temperatures>42 degrees C.

CONCLUSIONS

TLC-equipped dispersive electrodes were able to accurately measure skin temperature under the electrode. This technology is likely to prevent dispersive electrode related burns.

Effect of margins on ipsilateral breast tumor recurrence after breast conservation therapy for lymph node-negative breast carcinoma

BACKGROUND

Breast conservative surgery (CS) with radiotherapy (RT) is the most commonly used treatment for early-stage breast carcinoma. However, there is controversy regarding the importance of the pathologic margin status on the risk of ipsilateral breast tumor recurrence (IBTR). The current study evaluated the effect of the pathologic margin status on IBTR rates in a cohort of women with lymph node-negative breast carcinoma treated with CS and RT.

METHODS

Between August 1980 and December 1994, 452 women with pathologically lymph node-negative breast carcinoma were treated with CS and RT at Westmead Hospital (Westmead, Australia). Central pathology review was performed for all women. The final margins were negative for 352 women (77.9%), positive (invasive and/or in situ) for 42 women (9.3%), and indeterminate for 58 women (12.8%). Information regarding an extensive intraductal component (EIC), lymphovascular invasion, pathologic tumor size, histologic grade, and nuclear grade was available for most women. After macroscopic total excision of the tumor, all women received whole-breast irradiation (usually 45-50.4 grays [Gy]) and the majority of women also received a local tumor bed boost (range, 8-30 Gy).

RESULTS

After a median follow-up of 80 months, 34 women (7.5%) developed an IBTR. The crude 5-year rates of IBTR for women with negative margins, positive margins, and indeterminate margins were 3.1%, 11.9%, and 6.9%, respectively. For women with negative margins, the 5-year and 10-year actuarial rates of freedom from IBTR were 96% and 92%, respectively, compared with 88% and 75%, respectively, for women with positive margins (P = 0.003). Univariate analysis demonstrated that the only factors associated with a significantly higher risk of IBTR were age at diagnosis (P < 0.050) and margin status (P = 0.005). Multivariate analysis showed that both age and margin status were independent predictors of IBTR. None of 24 patients with an EIC and negative margins were found to have developed an IBTR.

CONCLUSIONS

The results of the current study were comparable to other published reports and supported the association of higher IBTR rates with positive or indeterminate margins compared with negative, pathologic margins. Furthermore, young age (age < 35 years at diagnosis) was associated with the highest risk of IBTR regardless of margin status.

Use of the St Gallen classification for patients with node-negative breast cancer may lead to overuse of adjuvant chemotherapy

BACKGROUND

The 1998 St Gallen classification was devised to guide clinicians in the use of adjuvant systemic therapy for women with early breast cancer. In this study, the classification was applied to a historical group of patients with node-negative breast cancer who were treated without adjuvant therapy.

METHODS

The St Gallen classification was applied to 421 women with breast cancer treated with conservative surgery and radiotherapy alone between 1979 and 1994. Primary tumour characteristics were reviewed centrally.

RESULTS

When the most stringent version of the St Gallen classification was applied (grade 2 or 3 tumours classified as "high risk"), only 10 per cent of patients were "low risk", with a 10-year distant relapse-free survival (DRFS) rate of 100 per cent, and 15 per cent were at "intermediate risk" (10-year DRFS rate of 94 per cent). The high-risk group (75 per cent of women) had a 10-year DRFS rate of 77 per cent (P < 0.01). If the St Gallen classification had been applied to all patients in this series who were aged less than 70 years, up to 91 per cent would have been recommended to have chemotherapy.

CONCLUSION

The St Gallen classification is an inaccurate measure of prognosis for patients with node-negative breast cancer and should be used with caution.

Treatment implications of a positive sentinel lymph node biopsy for patients with early-stage breast carcinoma

BACKGROUND

Sentinel lymph node (SLN) mapping and biopsy is emerging as an alternative to axillary lymph node dissection (ALND) in determining the lymph node status of patients with early-stage breast carcinoma. The hypothesis of the technique is that the SLN is the first lymph node in the regional lymphatic basin that drains the primary tumor. Non-SLN (NSLN) metastasis in the axilla is unlikely if the axillary SLN shows no tumor involvement, and, thus, further axillary interference may be avoided. However, the optimal treatment of the axilla in which an SLN metastasis is found requires ongoing evaluation. The objectives of this study were to evaluate the predictors for NSLN metastasis in the presence of a tumor-involved axillary SLN and to examine the treatment implications for patients with early-stage breast carcinoma.

METHODS

Between June 1998 and May 2000, 167 patients participated in the pilot study of SLN mapping and biopsy at Westmead Hospital. SLNs were identified successfully and biopsied in 140 axillae. All study patients also underwent ALND. The incidence of NSLN metastasis in the 51 patients with a SLN metastasis was correlated with clinical and pathologic characteristics.

RESULTS

Of 51 patients with a positive SLN, 24 patients (47%) had NSLN metastases. The primary tumor size was the only significant predictor for NSLN involvement. NSLN metastasis occurred in 25% of patients (95% confidence interval [95%CI], 10-47%) with a primary tumor size </= 20 mm and in 67% of patients (95%CI, 46-83%) with a primary tumor size > 20 mm (P = 0.005). The size of the SLN metastasis was not associated significantly with NSLN involvement. Three of 7 patients (43%) with an SLN micrometastasis (< 1 mm) had NSLN involvement compared with 38 of 44 patients (48%) with an SLN macrometastasis (> or = 1 mm).

CONCLUSIONS

The current study did not identify a subgroup of SLN positive patients in whom the incidence of NSLN involvement was low enough to warrant no further axillary interference. At present, a full axillary dissection should be performed in patients with a positive SLN.

Recent developments in stereotactic breast biopsy methodologies: an update for the surgical pathologist

Recently, there have been a number of new devices introduced for stereotactic biopsy of nonpalpable, mammographically detected lesions. The vacuum-assisted core biopsy (VACB) (Minimal Invasive Breast Biopsy (MIBB), U.S. Surgical, Norwalk, CT; Mammotome, Biopsys Medical, Cincinnati, OH) obtains multiple tissue cores (11-gauge) in a circumferential manner around the biopsy probe, inserted under stereotactic guidance. It provides more complete sampling of mammographic lesions than the conventional 14-gauge stereotactic core biopsy, reducing the number of unsatisfactory biopsies. The advanced breast biopsy instrumentation (ABBI) (United States Surgical Corporation, Norwalk, CT) system utilizes stereotactic technique and an oscillating blade-cutting mechanism to obtain a single large diameter (5 mm to 20 mm) tissue core, with the aim of obtaining an intact lesion in its entirety for histologic assessment. Its potential as a treatment option is still under investigation. Suggested protocols for specimen handling are presented together with a review of the recent literature. Close liaison with radiologists and surgeons performing these biopsies will allow the collection of further outcome data to evaluate the strengths and weaknesses of each technique.