TP53 mutations detected in circulating tumor cells present in the blood of metastatic triple negative breast cancer patients

Introduction

Circulating tumor cells (CTCs) are tumor cells shed from either primary tumors or its metastases that circulate in the peripheral blood of patients with metastatic cancers. The molecular characterization of the CTCs is critical to identifying the key drivers of cancer metastasis and devising therapeutic approaches. However, the molecular characterization of CTCs is difficult to achieve because their isolation is a major technological challenge.

Methods

CTCs from two triple negative breast cancer patients were enriched using CellSearch and single cells selected by DEPArray™. A TP53 R110 fs*13 mutation identified by next generation sequencing in the breast and chest skin biopsies of both patients was studied in single CTCs.

Results

From 6 single CTC isolated from one patient, 1 CTC had TP53 R110 delC, 1 CTC showed the TP53 R110 delG mutation, and the remaining 4 single CTCs showed the wild type p53 sequence; a pool of 14 CTCs isolated from the same patient also showed TP53 R110 delC mutation. In the tumor breast tissue of this patient, only the TP53 R110 delG mutation was detected. In the second patient a TP53 R110 delC mutation was detected in the chest wall skin biopsy; from the peripheral blood of this patient, 5 single CTC and 6 clusters of 2 to 6 CTCs were isolated; 3 of the 5 single CTCs showed the TP53 R110 delC mutation and 2 CTCs showed the wild type TP53 allele; from the clusters, 5 showed the TP53 R110 delC mutation, and 1 cluster the wild type TP53 allele. Single white blood cells isolated as controls from both patients only showed the wild type TP53 allele.

Conclusions

We are able to isolate uncontaminated CTCs and achieve single cell molecular analysis. Our studies showed the presence of different CTC sub-clones in patients with metastatic breast cancer. Some CTCs had the same TP53 mutation as their matching tumor samples although others showed either a different TP53 mutation or the wild type allele. Our results indicate that CTCs could represent a non-invasive source of cancer cells from which to determine genetic markers of the disease progression and potential therapeutic targets.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-014-0445-3) contains supplementary material, which is available to authorized users.

Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension Gμ below 10(-8) in some regions of the cosmic string parameter space.

An autoradiographic study of the flow of protein and RNA along peripheral nerve

Both chicken spinal cord and the posterior chamber of the rat eye have been injected with either [3H]leucine or [3H]orotic acid. The movement of newly synthesized protein and RNA down the sciatic and optic nerves was followed by means of autoradiography. Protein moved down both nerves by axoplasmic flow, the protein being confined to intra-axonal spaces. RNA appeared to move at about the same rate as protein, but much of the newly formed RNA appeared in structures outside the axons, particularly in Schwann and glial cells. There was, however a considerable proportion of the RNA inside the axons. This RNA may be involved in the direction of protein synthesis at sites along the axonal processes.

Auditory neuropathy: a potentially under-recognized neonatal intensive care unit sequela

Auditory neuropathy (AN) is a hearing disorder that affects newborns. Those with high-risk neonatal histories, family history of childhood hearing loss, and hyperbilirubinemia are at greatest risk. Current neonatal intensive care unit (NICU) hearing screening methods that rely only on otoacoustic emissions will fail to detect this disorder. Auditory neuropathy differs from conductive hearing loss and sensorineural hearing loss; a specific constellation of findings on audiologic evaluation are diagnostic of this disorder. The pathophysiology of AN is unclear; however, it may be caused by demyelinization or degeneration at points along the auditory pathway. The actual incidence of AN is unknown; it is more prevalent in high-risk infants. The course of AN varies widely among patients. Current management ranges from close monitoring of the child's development to cochlear implantation. Neonatal intensive care unit nurses need to be aware of this disorder to help support and educate at-risk families and to alert them of the need to monitor hearing and language development in their infants.

Short-term beta-amyloid vaccinations do not improve cognitive performance in cognitively impaired APP + PS1 mice

Prior work demonstrated that beta-amyloid (A beta) immunotherapy for 8 months prevented cognitive impairment in 16-month-old APP + PS1 transgenic mice. In the present study, 4 immunizations administered biweekly to cognitively impaired 16-month-old transgenic mice could not reverse deficits in working memory or reference memory in the radial arm water maze or in visual platform recognition, possibly because of inadequate antibody exposure. Nontransgenic mice showed cognitive savings between the 16- and 18-month test periods, but the transgenic groups did not. These results suggest that a longer period of active immunotherapy, or passive immunization, may be required to provide sufficient antibody titers to improve cognition in older transgenic mice. A beta-based immunotherapy for Alzheimer's disease will likely be more successful prophylactically than therapeutically.

A survey of tissue viability nurses' role and background in one region

The shift in NHS service provision towards primary care has made investigation of clinical nurse specialists' role in this setting an important issue. This article reports the findings of a preliminary survey of tissue viability nurses in one region

Presymptomatic motor neuron loss and reactive astrocytosis in the SOD1 mouse model of amyotrophic lateral sclerosis

In familial amyotrophic lateral sclerosis (fALS), there is a need to establish more precisely the progression of the disease, particularly whether there is gradual presymptomatic neuronal loss or an abrupt loss coinciding with the symptomatic stage. To elucidate this, we investigated the progression of motor neuron loss through morphological techniques, reactive astrocytosis, and expression of ubiquitin and neurofilament proteins, by immunohistochemistry, in SOD1 G93A mice with a protracted disease course and control mice. Loss of motor neurons in SOD1 G93A mice followed a biphasic progression, with an initial loss at 126 days of age, followed by a gradual loss from onset of symptoms through to end-stage disease. Reactive astrocytosis was first observed at 70 days of age and showed a gradual increase through to end-stage disease. This suggests that there is a need for early detection of fALS cases, and potential therapeutic treatments may be more beneficial if administered at an early stage.

The role of physicians in mammography referral for older Caribbean women in Canada

BACKGROUND

Despite the fact that the proportion of immigrant and minority women who consult a general practitioner about their health is similar to that of their Canadian-born counterparts, studies suggest that they are less likely to be screened for breast cancer. This study examines physician characteristics associated with mammography referral and perceived barriers to mammography among family physicians serving the Caribbean community of Toronto.

METHODS

The study consisted of a mail-back family physician survey.

RESULTS

Among the 64 physicians who responded to the survey, over half reported that they were "very likely" to refer women for mammography during a regular preventive check-up. Among physician variables, only the amount of time spent on patient education was significantly associated with the likelihood of referral. Regarding perceived barriers, for male physicians, patient refusal and intervention causing patient discomfort were significantly associated with referral. For female physicians, only forgetting to provide service was identified as a significant barrier to referral.

INTERPRETATION

An increased emphasis on patient education may help to increase screening referral among all physicians. Gender differences in perceived barriers to referral suggest that the gender of the physician is of major importance to the Caribbean community.

Leukemia inhibitory factor enhances regeneration in skeletal muscles after myoblast transplantation

Cell-based therapies, such as myoblast transfer therapy, are likely to become an integral part of any approach to treat myopathies such as Duchenne muscular dystrophy. Previous studies have shown that an increased level of regeneration in the host muscle enhances incorporation of donor myoblasts. Leukemia inhibitory factor (LIF) increases the number of dystrophic fibers expressing dystrophin after myoblast transplantation and enhances regeneration in injured and diseased muscle. Morphometric analysis was used to investigate whether an increased level of regeneration is induced by LIF after myoblast transplantation. We found that, in muscles treated with LIF, the number of fibers undergoing regeneration was increased. The increased incorporation of donor myoblasts and thus dystrophin expression induced by LIF may be due, at least in part, to an increased level of regeneration of dystrophic muscle.

In vivo and in vitro correction of the mdx dystrophin gene nonsense mutation by short-fragment homologous replacement

Targeted genetic correction of mutations in cells is a potential strategy for treating human conditions that involve nonsense, missense, and transcriptional splice junction mutations. One method of targeted gene repair, single-stranded short-fragment homologous replacement (ssSFHR), has been successful in repairing the common deltaF508 3-bp microdeletion at the cystic fibrosis transmembrane conductance regulator (CFTR) locus in 1% of airway epithelial cells in culture. This study investigates in vitro and in vivo application of a double-stranded method variant of SFHR gene repair to the mdx mouse model of Duchenne muscular dystrophy (DMD). A 603-bp wild-type PCR product was used to repair the exon 23 C-to-T mdx nonsense transition at the Xp21.1 dys locus in cultured myoblasts and in tibialis anterior (TA) from male mdx mice. Multiple transfection and variation of lipofection reagent both improved in vitro SFHR efficiency, with successful conversion of mdx to wild-type nucleotide at the dys locus achieved in 15 to 20% of cultured loci and in 0.0005 to 0.1% of TA. The genetic correction of mdx myoblasts was shown to persist for up to 28 days in culture and for at least 3 weeks in TA. While a high frequency of in vitro gene repair was observed, the lipofection used here appeared to have adverse effects on subsequent cell viability and corrected cells did not express dystrophin transcript. With further improvements to in vitro and in vivo gene repair efficiencies, SFHR may find some application in DMD and other genetic neuromuscular disorders in humans.

Leukemia inhibitory factor ameliorates muscle fiber degeneration in the mdx mouse

Although the muscles of the mdx mouse lack dystrophin, the protein absent in muscles of humans affected with Duchenne muscular dystrophy (DMD), the only mdx muscle to degenerate in a manner similar to those of DMD boys is the diaphragm. We have previously shown that leukemia inhibitory factor (LIF) is a trauma factor that enhances muscle repair in vivo and, when applied exogenously, increases the fiber size of mdx skeletal muscle. Furthermore, we developed a controlled release device for LIF based on a calcium alginate rod (release rate about 0.5% per day). These rods were sutured to the abdominal surface of the hemidiaphragm of mdx mice 3 months old. At age 6 months the mice were killed and the diaphragm muscles fixed and sectioned. The sections showed obvious muscle degeneration at 3 months of age in mdx mouse diaphragms and further degeneration at 6 months in saline-perfused muscle. Hemidiaphragm muscles continuously exposed to LIF over the same period contained more normal myofibers, larger regenerated fibers, and less adipose tissue and other non-contractile tissue. Morphometric analysis of the diaphragm sections was carried out. The LIF-treated animals showed a significant increase in fiber number and size compared to saline rod controls. The amount of nonmuscle (connective tissue and adipose tissue) was significantly reduced and the maximum force-producing capacity of isolated diaphragm muscle strips was higher in LIF-treated mice. The results demonstrate that LIF treatment ameliorates the dystrophic abnormalities in mdx mouse diaphragm.

Palliative care: community nurses' perceptions of quality

OBJECTIVES

To identify community nurses' perceptions of quality care provision for patients requiring palliative care.

DESIGN

Semi-structured interviews were conducted with community nurses working within the district nursing service. An adaptation of Flanagan's critical incident technique was employed to elicit factors associated with high or poor quality palliative care. Interviews were tape recorded and transcribed. Data were analysed using thematic content analysis, recurrent themes being agreed by the research team.

SETTING

One community healthcare trust.

SUBJECTS

62 members of the district nursing team (grades B-H).

RESULTS

Respondents recounted the context in which high quality palliative care could be provided, the actions required, and the indicators that suggested the desired level of care had been achieved. Key factors identified were: the early referral of patients to the district nursing service, family circumstances, the availability of time, the accessibility of services and equipment, and the relationship with other healthcare professionals and informal carers. There was a general view that a positive outcome had been achieved when patients retained control over their circumstances and died a peaceful death, in the place of their choice, supported by their family.

CONCLUSIONS

Community nurses were able to articulate clearly the essential components of high quality care. Whilst these factors do not represent a comprehensive list, they are put forward as a useful starting point for standard setting and subsequent audit.

Community nurses' perceptions of patient 'compliance' in wound care: a discourse analysis

As part of an interview study of community nurses' perceptions of their work, 62 staff working within the district nursing service in one English National Health Service Trust (grades B-H) were asked to recount occasions when they had been involved in wound care and to discuss the ways in which working with patients who required such care could be either enhanced or made difficult. A large number of respondents expressed the view that non-compliance could pose serious problems for the management of wounds. Data relating to compliance are presented here and are interpreted in the light of discourse analysis, an approach which permits the researcher to focus on the meanings underlying the communications of research participants and to interpret those meanings in the light of social and cultural mores and influences. The authors found that non-compliance could be explained by nurses in a number of different ways. These ranged from passive resistance, which could be due to ignorance or lack of motivation, through overt refusal, to deliberate interference in order to prolong treatment. It also seeks to outline some of the factors that appear to motivate the nurses' desire to achieve compliance.

Increased levels of leukemia inhibitory factor mRNA in muscular dystrophy and human muscle trauma

Leukemia inhibitory factor (LIF) is an important muscle trauma factor both after crush injury and in the mdx mouse dystrophy model. It is important to establish which growth factors have a role in human muscle regeneration due to potential clinical therapeutic applications. As there is limited information concerning LIF expression in human muscle, we investigated the relative levels of LIF messenger ribonucleic acid (mRNA) in human muscle injury. Semiquantitative reverse transcriptase followed by polymerase chain reaction was used to amplify LIF message. We found that although LIF mRNA is expressed in low levels in control muscle, a sevenfold increase occurred after orthopedic muscle trauma and a marked 19-fold increase in dystrophic muscle (P < 0.002). These results indicate that LIF mRNA is upregulated in surgical and especially medical muscle injury with repeated myonecrosis. Muscle growth factors such as LIF may assist in future muscle rehabilitation after injury.

An evaluation of information cards as a means of improving communication between hospital and primary care for women with breast cancer

This paper describes an intervention study aimed at improving communication between hospital services and the primary health care team. A series of information cards were developed by breast specialist secondary care professionals for members of the primary health care team. Women with breast cancer were involved in the communication pathway and were asked to take the information cards to their own general practitioner (GP) practice. It was envisaged that women would be more likely to utilize the primary health care team for information if they were aware that the primary health care team was in receipt of information specific to the treatment they had received. Women newly diagnosed with breast cancer were allocated to either an intervention (n=38) or non-intervention (n=38) group. Patient interviews were carried out around the time of diagnosis and at 4 months from diagnosis. Interviews were also carried out with 31 GPs to ascertain their views on the provision of information for women with breast cancer, and on the information cards if relevant. The study findings were interesting although not significant in terms of the direction anticipated. The cards did not impact on the utilization of the primary health care team and women in the intervention group were no more likely to utilize primary care sources of information than women in the non-intervention group. Factors such as the long-standing relationship women had with their GP, the perceived lack of specialist knowledge on the part of GPs and district nurses, and the women's perception that information seeking was not a tangible reason for primary care contact had an impact on information-seeking behaviour.