Abstract P5-18-02: A quantitative centrosomal amplification score (CAS) predicts local recurrence in ductal carcinoma in situ

Background: About 60-80% of ductal carcinoma in situ (DCIS) cases are high-grade (HG) DCIS with an elevated risk of local recurrence (LR) even after a lumpectomy. Patients are often under or over treated due to the lack of accurate recurrence risk prediction models. Current prognostic models such as OncotypeDX and Van Nuys Prognostic Index (VNPI) lack consistency and are limited to a specific subset of patients. Here in this study, we show that the extent of centrosome amplification (CA) in a DCIS lesion can predict the risk of LR after lumpectomy. CA refers to presence of supernumerary or large centrosomes and is a characteristic of pre-invasive lesions, and breast tumors, and promotes erroneous mitoses and chromosomal instability.

Methods: We have pioneered a semi-automated pipeline that integrates immunofluorescence confocal microscopy with digital image analysis and yields a quantitative Centrosomal Amplification Score (CAS) for each patients' tumor sample by evaluating severity and frequency of centrosomal aberrations therein. To this end, we first immunofluorescently stained centrosomes in formalin fixed paraffin embedded resection samples from DCIS patients (discovery cohort n=133 and a validation cohort n=119) using an antibody against γ-tubulin, and co-stained nuclei with DAPI. Next, we imaged the slides and processed the raw 3D image data using IMARIS Biplane 8.2 3D volume rendering software. Finally, we calculated centrosome numbers and volume in ˜250 cells from each patient sample. Using a mathematical algorithm, we generated a composite CAS score for each patient sample by integrating the numerical (CASi) and structural (CASm) aberrations.

Results: We found that DCIS patients with recurrence exhibited higher CAS. Intriguingly, higher CAS was also associated with greater risk of developing ipsilateral breast events [Hazard ratio (HR) =7.58 for discovery cohort and HR=5.8 for validation cohort, p<0.0001] which remained significant (HR=8.5 for discovery and HR=3.39, p<0.0001) after accounting for the confounding factors like age, tumor size, comedo necrosis and radiotherapy. Kaplan Meir survival analysis indicated that high CAS was associated with poor recurrence-free survival (RFS) (p<0.001). For the high and low CAS groups, the 5-year risk of recurrence was 87.5% and 12.5% respectively (p<0.001). In our discovery cohort, a head-to-head comparison of the ability of VNPI and CAS to predict recurrence illuminated that CAS was able to stratify the DCIS group in recurrence and recurrence-free group with much higher significance (p<0.0001) than the Van Nuys Prognostic Index (VNPI) (HRs for CAS- 8.8 vs. VNPI 0.959). Finally, the Harrell's concordance index using SAS PROC PHREG tests yielded that the probability of a patient with poorer/lower RFS to be in the high CAS group is 76.2%.

Conclusion: Our data compellingly show that CAS quantifies the risk of recurrence in DCIS patients with the highest concordance and provides a novel and innovative tool to tailor their treatment based on their risk profile.

Citation Format: Mittal K, Kaur J, Wei G, Toss MS, Osan RM, Janssen EA, Søiland H, Rakha EA, Rida PC, Aneja R. A quantitative centrosomal amplification score (CAS) predicts local recurrence in ductal carcinoma in situ [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-18-02.

Association between androgen receptor polymorphic CAG and GGC repeat lengths and cryptorchidism: A meta-analysis of case-control studies

INTRODUCTION

Previous studies have revealed the relationship between androgen receptor (AR) CAG and/or GGC polymorphisms and risk of cryptorchidism, yet the results have been elusive and controversial.

AIM

To determine whether AR polymorphic CAG and/or GGC repeats are related to cryptorchidism.

STUDY DESIGN

The relevant studies were obtained from PubMed, Embase, China National Knowledge Infrastructure, and Wanfang. The pooled odds ratios with 95% confidence intervals (CIs) were used to assess the strength of associations. Subgroup analyses were performed based on ethnicity and source of controls. Moreover, Begg's funnel plots and Egger's linear regression test were conducted to determine publication bias.

RESULTS

Eight case-control studies containing 321 patients and 784 normal controls were included. There was a significant association between longer CAG repeats and cryptorchidism risk (weighted mean difference (WMD) = 0.62; 95% CIs 0.06, 1.18; P = 0.031). Moreover, there was a significant association between the longer GGC repeats and cryptorchidism risk (WMD = 0.87; 95% CIs 0.04, 1.74; P = 0.040). There was significant association between the longer CAG repeats and bilateral cryptorchidism (WMD = 0.88; 95% CIs -0.18, 1.94; P = 0.011), while there was no significant association between the longer CAG repeats and unilateral cryptorchidism (WMD = -0.09; 95% CIs -0.50, 0.31; P = 0.554). There were significant associations between the longer GGC repeats and unilateral cryptorchidism (WMD = 0.88; 95% CIs -0.30, 2.05; P = 0.005) and bilateral cryptorchidism (WMD = 1.35; 95% CIs -0.52, 3.21; P = 0.000). Stratifying analysis revealed an association between longer CAG/GGC repeats and cryptorchidism in Caucasian populations from Europe (WMD = 0.73; 95% CIs 0.00, 1.46; P = 0.017), while there was no association with Asian populations.

DISCUSSION

This meta-analysis found that CAG/GGC repeats in the AR gene were longer in cryptorchidism patients compared to controls. Both the longer CAG repeats and GGC repeats in the AR gene were associated with cryptorchidism risk. The longer CAG repeats were associated with bilateral cryptorchidism, whereas the longer GGC repeats were associated with unilateral and bilateral cryptorchidism. Stratifying analysis revealed an association between longer CAG/GGC repeats and cryptorchidism in Caucasian populations from Europe, while there was no association between longer CAG/GGC repeats and cryptorchidism in Asian populations.

CONCLUSION

The CAG/GGC repeats in the AR gene were longer in cryptorchidism than in controls. Longer CAG repeats may play a role in determining bilateral cryptorchidism, and longer GGC repeats may play a role in determining unilateral and bilateral cryptorchidism. These observations were more applicable to Caucasian populations.

Mechanism of Nucleoside Triphosphate Diphosphohydrolase-1-Associated Imbalance in Adenosine Diphosphate Degradation, B-Cell Activation, and Related Injury During Acute Antibody-Mediated Rejection

OBJECTIVE

The objective of this study was to investigate the effect of nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) during acute antibody-mediated rejection (AMR).

METHODS

NTPDase1 overexpression, NTPDase1 knockout, and wild-type nude mice skin graft models were used to induce acute AMR. NTPDase1 expression in B cells, NTPDase1 messenger RNA expression in skin grafts, extracellular adenosine diphosphate (ADP) concentration, B-cell volume and surface antigens expression, average platelet transport rate, and ultrastructure and apoptosis of skin graft cells were investigated.

RESULTS

During acute AMR in nude mice, higher NTPDase1 expression caused lower extracellular ADP concentration, smaller increase in B-cell volume, and major histocompatibility complex II surface antigen expression, suggesting a negative correlation between them; higher NTPDase1 expression also caused slower average platelet transport rate and less severe skin graft injury, suggesting a negative correlation between them. Pretreatment with high-dose exogenous NTPDase1 inhibited platelet activation and protected skin grafts, but it resulted in prolonged bleeding time (by 51.4%) and prolonged coagulation time (by 44.1%).

CONCLUSION

An NTPDase1-associated imbalance in extracellular ADP degradation may contribute to B-cell activation, platelet activation, and more severe skin graft injury in nude mice. Pretreatment with high-dose exogenous NTPDase1 effectively protected skin grafts in nude mice at 1 week, but it increased the risk of bleeding.

A novel splice site mutation of the PRKAR1A gene, C.440+5 G>C, in a Chinese family with Carney complex

BACKGROUND

Carney complex (CNC) is an extremely rare, multiple endocrine neoplasia syndrome that occurs in an autosomal dominant manner. Mutations in PRKAR1A have been reported to be a common genetic cause of CNC.

METHODS

In this study, we reported a Chinese pedigree of CNC that manifests mainly as spotty skin pigmentation and primary pigmented nodular adrenocortical disease. Whole blood samples of this pedigree were collected for DNA/RNA analysis. Polymerase chain reaction (PCR) and reverse-transcription polymerase chain reaction analyses were performed to amplify the 11 exons and adjacent introns of PRKAR1A. Direct sequencing was used to detect the mutation, and DNA from 70 Han Chinese people was extracted and sequenced as a control to estimate the frequency of the identified mutation.

RESULTS

Within the pedigree, ten patients with CNC were identified, and a novel heterozygous mutation (c.440+5 G>C in intron 4a) was identified in the PRKAR1A gene. PCR amplification of cDNA from the control subjects and patients was performed. Agarose gel electrophoresis showed only one wild-type band in the cDNA corresponding to the former group, whereas an extra band was present in samples from the latter group corresponding to the skipping of exon 4a; this confirms that the variant affects PRKAR1A splicing.

CONCLUSION

In conclusion, the c.440+5 G>C mutation is a new splice site mutation that has not been reported and has the potential to broaden the mutational spectrum of PRKAR1A that is associated with CNC, which would facilitate genetic diagnosis and counseling for CNC.

Comparative symbiotic plasmid analysis indicates that symbiosis gene ancestor type affects plasmid genetic evolution

Rhizobial symbiotic plasmids play vital roles in mutualistic symbiosis with legume plants by executing the functions of nodulation and nitrogen fixation. To explore the gene composition and genetic constitution of rhizobial symbiotic plasmids, comparison analyses of 24 rhizobial symbiotic plasmids derived from four rhizobial genera was carried out. Results illustrated that rhizobial symbiotic plasmids had higher proportion of functional genes participating in amino acid transport and metabolism, replication; recombination and repair; carbohydrate transport and metabolism; energy production and conversion and transcription. Mesorhizobium amorphae CCNWGS0123 symbiotic plasmid - pM0123d had similar gene composition with pR899b and pSNGR234a. All symbiotic plasmids shared 13 orthologous genes, including five nod and eight nif/fix genes which participate in the rhizobia-legume symbiosis process. These plasmids contained nod genes from four ancestors and fix genes from six ancestors. The ancestral type of pM0123d nod genes was similar with that of Rhizobium etli plasmids, while the ancestral type of pM0123d fix genes was same as that of pM7653Rb. The phylogenetic trees constructed based on nodCIJ and fixABC displayed different topological structures mainly due to nodCIJ and fixABC ancestral type discordance. The study presents valuable insights into mosaic structures and the evolution of rhizobial symbiotic plasmids.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study compared 24 rhizobial symbiotic plasmids that included four genera and 11 species, illuminating the functional gene composition and symbiosis gene ancestor types of symbiotic plasmids from higher taxonomy. It provides valuable insights into mosaic structures and the evolution of symbiotic plasmids.

Effect of renal sympathetic denervation on ventricular and neural remodeling

Background

This study assessed the therapeutic effects of renal sympathetic denervation (RDN) on post-myocardial infarction (MI) ventricular remodeling and sympathetic neural remodeling in dogs. The possible mechanisms and optimal time for treatment are discussed.

Methods

We randomly assigned 30 dogs to five groups: RDN 1 week before MI (RDN1w + MI; n = 6), RDN 1 week after MI (MI1w + RDN; n = 6), RDN 2 weeks after MI (MI2w + RDN; n = 6), control (N; n = 6), and MI (n = 6). A canine model of myocardial infarction was established by interventional occlusion with a gelatin sponge via the femoral artery. Brain natriuretic peptide (BNP) and endothelin-1 (ET-1) levels were measured and echocardiography was performed to assess cardiac function and heart size. All dogs were killed at the end of the experiment and samples of cardiac and renal arteries were obtained. The expression of matrix metalloproteinase (MMP)-2 and MMP-9 in cardiac and of tyrosine hydroxylase (TH) in renal arteries was assessed by immunohistochemistry. Sympathetic innervations in the infarction border zone were investigated via Western blotting and real-time PCR.

Results

Left ventricular function in the MI group decreased significantly, while plasma BNP and ET-1 levels as well as MMP-2 and MMP-9 expression increased. Compared with the MI group, the RD groups showed significantly reduced MMP‑2, MMP‑9, TH, and growth-associated protein (GAP) 43 expression in the RDN1w + MI, MI1w + RDN, and MI2w + RDN groups was significantly improved. Additionally, the expression of TH in renal arteries decreased after RDN.

Conclusion

RDN has preventive and therapeutic effects on post-MI ventricular remodeling and sympathetic neural remodeling. The mechanism of RDN is likely mediated through restraint of renal sympathetic nerve activity.

Photonic ring resonator filters for astronomical OH suppression

Ring resonators provide a means of filtering specific wavelengths from a waveguide, and optionally dropping the filtered wavelengths into a second waveguide. Both of these features are potentially useful for astronomical instruments. In this paper we focus on their use as notch filters to remove the signal from atmospheric OH emission lines from astronomical spectra. We derive the design requirements for ring resonators for OH suppression from theory and finite difference time domain simulations. We find that rings with small radii (< 10 μm) are required to provide an adequate free spectral range, leading to high index contrast materials such as Si and Si₃N₄. Critically coupled rings with high self-coupling coefficients should provide the necessary Q factors, suppression depth, and throughput for efficient OH suppression, but will require post-inscription tuning of the coupling and the resonant wavelengths. The overall prospects for the use of ring resonators in astronomical instruments is promising, provided efficient fibre-chip coupling can be achieved.

Expression and characterization of a lipase-related protein in the malpighian tubules of the Chinese oak silkworm, Antheraea pernyi

Lipases are ubiquitous enzymes in nature, which play a crucial role in fat metabolism by catalyzing the hydrolysis of triacylglycerol to free fatty acids and glycerol. However, reports concerning insect lipase are rare. In this study, we studied the expression and activity of a lipase-related protein from Antheraea pernyi (ApLRP). Recombinant ApLRP was expressed in Escherichia coli cells and used to raise rabbit anti-ApLRP polyclonal antibodies. ApLRP mRNA and protein expression were abundant in the midgut and malpighian tubules, respectively. After challenge with four different microorganisms (E. coli, Beauveria bassiana, Micrococcus luteus and nuclear polyhedrosis virus), the expression levels of ApLRP mRNA in midgut were inducted significantly compared with the control. The different pathogens induced different ApLRP gene expression patterns. The optimum temperature and pH for the enzyme's activity were 35°C and 7.0, respectively. ApLRP activity was stimulated in the presence of Mg2+, Na+, Ca2+ and b-mercaptoethanol; while Zn2+, Cu2+ and Fe3+ inhibited its activity. Detergents such as SDS, glycerol and Tween-20 increased the lipase activity by 20-30%. Our results indicated that ApLRP might play an important role in the innate immunity of insects.

Sea-level haemoglobin concentration is associated with greater exercise capacity in Tibetan males at 4200 m

NEW FINDINGS

What is the topic of this review? Recent developments link relatively lower hemoglobin concentration in Tibetans at high altitude to exercise capacity and components of oxygen transport. What advances does it highlight? Haemoglobin concentration (ranging from 15.2 to 22.9 g dl(-1) ) in Tibetan males was negatively associated with peak oxygen (O2 ) uptake per kilogram, cardiac output and muscle O2 diffusion conductance. Most variance in the peak O2 uptake per kilogram of Tibetan males was attributed to cardiac output, muscle diffusional conductance and arterial partial pressure of CO2 . The mechanisms underlying these differences in oxygen transport in Tibetans require additional analyses. Despite residence at >4000 m above sea level, many Tibetan highlanders, unlike Andean counterparts and lowlanders at altitude, exhibit haemoglobin concentration ([Hb]) within the typical sea-level range. Genetic adaptations in Tibetans are associated with this relatively low [Hb], yet the functional relevance of the lower [Hb] remains unknown. To address this, we examined each major step of the oxygen transport cascade [ventilation (VE), cardiac output (QT) and diffusional conductance in lung (DL) and muscle (DM)] in Tibetan males at maximal exercise on a cycle ergometer. Ranging from 15.2 to 22.9 g dl(-1) , [Hb] was negatively associated with peak O2 uptake per kilogram (r = -0.45, P < 0.05) and both cardiac output (QT/kg: r = -0.54, P < 0.02) and muscle O2 diffusion conductance (DM/kg: r = -0.44, P < 0.05) but not ventilation, arterial partial pressure of O2 or pulmonary diffusing capacity. Most variance in peak O2 uptake per kilogram was attributed to QT, DM and arterial partial pressure of CO2 (r(2)  = 0.90). In summary, lack of polycythaemia in Tibetans is associated with increased exercise capacity, which is explained by elevated cardiac, muscle and, to a small extent, ventilatory responses rather than pulmonary gas exchange. Whether lower [Hb] is the cause or result of these changes in O2 transport or is causally unrelated will require additional study.

What hides behind the MASC: clinical response and acquired resistance to entrectinib after ETV6-NTRK3 identification in a mammary analogue secretory carcinoma (MASC)

Here, we describe the dramatic response of a patient with an ETV6-NTRK3-driven mammary analogue secretory carcinoma to treatment with a pan-Trk inhibitor, and the development of acquired resistance linked to a novel NTRK3 mutation that interferes with drug binding. This case emphasizes how molecular profiling can identify therapies for rare diseases and dissect mechanisms of drug resistance.

Background

Mammary analogue secretory carcinoma (MASC) is a recently described pathologic entity. We report the case of a patient with an initial diagnosis of salivary acinic cell carcinoma later reclassified as MASC after next-generation sequencing revealed an ETV6-NTRK3 fusion.

Patients and methods

This alteration was targeted with the pan-Trk inhibitor entrectinib (Ignyta), which possesses potent in vitro activity against cell lines containing various NTRK1/2/3 fusions.

Results

A dramatic and durable response was achieved with entrectinib in this patient, followed by acquired resistance that correlated with the appearance of a novel NTRK3 G623R mutation. Structural modeling predicts that this alteration sterically interferes with drug binding, correlating to decreased sensitivity to drug inhibition observed in cell-based assays.

Conclusions

This first report of clinical activity with TrkC inhibition and the development of acquired resistance in an NTRK3-rearranged cancer emphasize the utility of comprehensive molecular profiling and targeted therapy for rare malignancies (NCT02097810).

Isolation and characterisation of cDNA encoding a wheat heavy metal-associated isoprenylated protein involved in stress responses

In cells, metallochaperones are important proteins that safely transport metal ions. Heavy metal-associated isoprenylated plant proteins (HIPPs) are metallochaperones that contain a metal binding domain and a CaaX isoprenylation motif at the carboxy-terminal end. To investigate the roles of wheat heavy metal-associated isoprenylated plant protein (TaHIPP) genes in plant development and in stress responses, we isolated cDNA encoding the wheat TaHIPP1 gene, which contains a heavy metal-associated domain, nuclear localisation signals and an isoprenylation motif (CaaX motif). Quantitative real-time PCR analysis indicated that the TaHIPP1 gene was differentially expressed under biotic and abiotic stresses. Specifically, TaHIPP1 expression was up-regulated by ABA exposure or wounding. Additionally, TaHIPP1 over-expression in yeast (Schizosaccharomyces pombe) significantly increased the cell growth rate under Cu(2+) and high salinity stresses. The nuclear localisation of the protein was confirmed with confocal laser scanning microscopy of epidermal onion cells after particle bombardment with chimeric TaHIPP1-GFP constructs. In addition, TaHIPP1 was shown to enhance the susceptibility of wheat to Pst as determined by virus-induced gene silencing. These data indicate that TaHIPP1 is an important component in defence signalling pathways and may play a crucial role in the defence response of wheat to biotic and certain abiotic stresses.

Detection of Citrus leprosis virus C using specific primers and TaqMan probe in one-step real-time reverse-transcription polymerase chain reaction assays

Citrus leprosis virus C (CiLV-C), a causal agent of the leprosis disease in citrus, is mostly present in the South and Central America and spreading toward the North America. To enable better diagnosis and inhibit the further spread of this re-emerging virus a quantitative (q) real-time reverse transcription polymerase chain reaction (qRT-PCR) assay is needed for early detection of CiLV-C when the virus is present in low titer in citrus leprosis samples. Using the genomic sequence of CiLV-C, specific primers and probe were designed and synthesized to amplify a 73 nt amplicon from the movement protein (MP) gene. A standard curve of the 73 nt amplicon MP gene was developed using known 10(10)-10(1) copies of in vitro synthesized RNA transcript to estimate the copy number of RNA transcript in the citrus leprosis samples. The one-step qRT-PCR detection assays for CiLV-C were determined to be 1000 times more sensitive when compared to the one-step conventional reverse transcription polymerase chain reaction (RT-PCR) CiLV-C detection method. To evaluate the quality of the total RNA extracts, NADH dehydrogenase gene specific primers (nad5) and probe were included in reactions as an internal control. The one-step qRT-PCR specificity was successfully validated by testing for the presence of CiLV-C in the total RNA extracts of the citrus leprosis samples collected from Belize, Costa Rica, Mexico and Panama. Implementation of the one-step qRT-PCR assays for CiLV-C diagnosis should assist regulatory agencies in surveillance activities to monitor the distribution pattern of CiLV-C in countries where it is present and to prevent further dissemination into citrus growing countries where there is no report of CiLV-C presence.

Low haemoglobin concentration in Tibetan males is associated with greater high-altitude exercise capacity

Tibetans living at high altitude have adapted genetically such that many display a low erythropoietic response, resulting in near sea-level haemoglobin (Hb) concentration. We hypothesized that absence of the erythropoietic response would be associated with greater exercise capacity compared to those with high [Hb] as a result of beneficial changes in oxygen transport. We measured, in 21 Tibetan males with [Hb] ranging from 15.2 g dl(-1) to 22.9 g dl(-1) (9.4 mmol l(-1) to 14.2 mmol l(-1) ), [Hb], ventilation, volumes of O2 and CO2 utilized at peak exercise (V̇O2 and V̇CO2), heart rate, cardiac output and arterial blood gas variables at peak exercise on a cycle ergometer at ∼4200 m. Lung and muscle O2 diffusional conductances were computed from these measurements. [Hb] was related (negatively) to V̇O2 kg(-1) (r = -0.45, P< 0.05), cardiac output kg(-1) (QT kg(-1) , r = -0.54, P < 0.02), and O2 diffusion capacity in muscle (DM kg(-1) , r = -0.44, P<0.05), but was unrelated to ventilation, arterial partial pressure of O2 (PaO2) or pulmonary diffusing capacity. Using multiple linear regression, variance in peak V̇O2 kg(-1) was primarily attributed to QT, DM, and PCO2 (R(2) = 0.88). However, variance in pulmonary gas exchange played essentially no role in determining peak V̇O2. These results (1) show higher exercise capacity in Tibetans without the erythropoietic response, supported mostly by cardiac and muscle O2 transport capacity and ventilation rather than pulmonary adaptations, and (2) support the emerging hypothesis that the polycythaemia of altitude, normally a beneficial response to low cellular PO2, may become maladaptive if excessively elevated under chronic hypoxia. The cause and effect relationships among [Hb], QT, DM, and PCO2 remain to be elucidated.

XBP1 mitigates aminoglycoside-induced endoplasmic reticulum stress and neuronal cell death

Here we study links between aminoglycoside-induced mistranslation, protein misfolding and neuropathy. We demonstrate that aminoglycosides induce misreading in mammalian cells and assess endoplasmic reticulum (ER) stress and unfolded protein response (UPR) pathways. Genome-wide transcriptome and proteome analyses revealed upregulation of genes related to protein folding and degradation. Quantitative PCR confirmed induction of UPR markers including C/EBP homologous protein, glucose-regulated protein 94, binding immunoglobulin protein and X-box binding protein-1 (XBP1) mRNA splicing, which is crucial for UPR activation. We studied the effect of a compromised UPR on aminoglycoside ototoxicity in haploinsufficient XBP1 (XBP1^+/−) mice. Intra-tympanic aminoglycoside treatment caused high-frequency hearing loss in XBP1^+/− mice but not in wild-type littermates. Densities of spiral ganglion cells and synaptic ribbons were decreased in gentamicin-treated XBP1^+/− mice, while sensory cells were preserved. Co-injection of the chemical chaperone tauroursodeoxycholic acid attenuated hearing loss. These results suggest that aminoglycoside-induced ER stress and cell death in spiral ganglion neurons is mitigated by XBP1, masking aminoglycoside neurotoxicity at the organismal level.