[Texture analysis of diffusion-weighted magnetic resonance imaging to identify atypically enhanced small hepatocellular carcinoma and dysplastic nodules under the background of cirrhosis]

Objective: To investigate the value of texture analysis based on diffusion-weighted magnetic resonance imaging (DWI) in the differential diagnosis of atypically enhanced small hepatocellular carcinoma (sHCC) and dysplastic nodules (DNs) in liver cirrhosis. Methods: Data of 59 cases with atypical enhancement and solitary cirrhotic nodule (≤2 cm) confirmed by dynamic contrast enhanced MRI and surgical pathology specimen were analyzed retrospectively. Among them, 37 cases were of atypically enhanced sHCC and 22 cases of DNS. The DWI signal characteristics of the lesions were analyzed to measure the average apparent diffusion coefficient (ADC) value of the lesions, and the ADC ratio of the lesion to the liver parenchyma. MaZda software was used to manually draw the region of interest to extract the texture parameters of DWI lesions. The three sets (combination of Fisher coefficient, classification of error probability combined with average correlation coefficient and interactive information) were used to select the thirty optimal texture parameters. Raw data analysis (RDA), principal component analysis (PCA), linear discriminant analysis (LDA) and non-linear discriminant analysis (NDA) were performed for texture classification. The difference of ADC value and ADC ratio between sHCC and DNS group was compared by independent sample t-test, and χ2 test was used to compare the count data (or rate). ROC curve analysis was used to evaluate the diagnostic efficiency. Results: The sensitivity, specificity and accuracy of DWI high-signal in the identification of atypically enhanced sHCC and DNs were 94.6% (35/37), 68.2% (15/22), and 84.7% (50/59), respectively. The ADC ratio of atypically enhanced sHCC was significantly lower than DNs, and the difference was statistically significant (t = 2.99, P = 0.002). The sensitivity, specificity, and accuracy for the diagnosis of atypically enhanced sHCC were 73.0% (27/37), 72.7% (16/22) and 72.9% (43/59), respectively. The sensitivity, specificity and accuracy of DWI texture analysis in diagnosing atypically enhanced sHCC were 94.6% (35/37), 95.5% (21/22) and 94.9% (56/59).The diagnostic efficiency of DWI texture analysis (AUC = 0.94) was significantly higher than DWI high-signal (AUC = 0.81) and ADC ratio (AUC = 0.72). Conclusion: The texture analysis based on DWI can identify atypically enhanced sHCC and dysplastic nodules under the background of cirrhosis, and its efficacy is better than qualitative and quantitative DWI.

Structure-function relationships of the soluble form of the antiaging protein Klotho have therapeutic implications for managing kidney disease

The fortuitously discovered antiaging membrane protein αKlotho (Klotho) is highly expressed in the kidney, and deletion of the Klotho gene in mice causes a phenotype strikingly similar to that of chronic kidney disease (CKD). Klotho functions as a co-receptor for fibroblast growth factor 23 (FGF23) signaling, whereas its shed extracellular domain, soluble Klotho (sKlotho), carrying glycosidase activity, is a humoral factor that regulates renal health. Low sKlotho in CKD is associated with disease progression, and sKlotho supplementation has emerged as a potential therapeutic strategy for managing CKD. Here, we explored the structure-function relationship and post-translational modifications of sKlotho variants to guide the future design of sKlotho-based therapeutics. Chinese hamster ovary (CHO)- and human embryonic kidney (HEK)-derived WT sKlotho proteins had varied activities in FGF23 co-receptor and β-glucuronidase assays in vitro and distinct properties in vivo Sialidase treatment of heavily sialylated CHO-sKlotho increased its co-receptor activity 3-fold, yet it remained less active than hyposialylated HEK-sKlotho. MS and glycopeptide-mapping analyses revealed that HEK-sKlotho is uniquely modified with an unusual N-glycan structure consisting of N,N'-di-N-acetyllactose diamine at multiple N-linked sites, one of which at Asn-126 was adjacent to a putative GalNAc transfer motif. Site-directed mutagenesis and structural modeling analyses directly implicated N-glycans in Klotho's protein folding and function. Moreover, the introduction of two catalytic glutamate residues conserved across glycosidases into sKlotho enhanced its glucuronidase activity but decreased its FGF23 co-receptor activity, suggesting that these two functions might be structurally divergent. These findings open up opportunities for rational engineering of pharmacologically enhanced sKlotho therapeutics for managing kidney disease.

Liraglutide increases bone formation and inhibits bone resorption in rats with glucocorticoid-induced osteoporosis

OBJECTIVE

This study aimed to investigate the effects of liraglutide on bone metabolism markers in rat models with glucocorticoid-induced osteoporosis (GIOP), including the effects on bone mass, bone tissue microstructure, bone biomechanics, and bone turnover markers.

METHOD

Thirty male Sprague-Dawley rats aged 8 weeks were randomly divided into three groups: the control group (n = 10) was intramuscularly injected with an equal volume of 0.9% sodium chloride, the dexamethasone group (n = 10) was intramuscularly injected with dexamethasone at 1 mg/kg (twice a week) to induce GIOP, the dexamethasone plus liraglutide group (n = 10) was subcutaneously injected with liraglutide at 200 μg/kg daily, simultaneously. The bilateral femurs and the fifth lumbar vertebrae were collected after 12 weeks to perform micro-computed tomography and bone biomechanical examinations. Also, tartrate-resistant acid phosphatase (TRACP), cross-linked carboxy-terminal telopeptide of type I collagen (CTX-I), alkaline phosphatase (ALP), and osteocalcin (OC) were tested.

RESULTS

The bone mineral density (BMD), bone microstructure, and bone biomechanical markers reduced significantly in the dexamethasone group compared with the control group. The bone resorption indicators (TRACP and CTX-I) increased, while the bone formation indicators (ALP and OC) decreased. After liraglutide treatment, BMD, bone microstructure, and bone biomechanical markers improved significantly. Moreover, TRACP and CTX-I decreased significantly, while ALP and OC increased compared with the dexamethasone group.

CONCLUSIONS

Liraglutide improved BMD, bone microstructure, and bone strength and reversed GIOP, primarily through the reduction of bone resorption and promotion of bone formation.

Surgical management and outcomes of duodenal gastrointestinal stromal tumors

BACKGROUND AND STUDY AIMS

This retrospective study purports to examine these characteristics and compare the surgical procedures available and appropriate for the treatment of patients affected by duodenal GISTs.

PATIENTS AND METHODS

A retrospective examination of reports and studies carried out between May 2012 and March 2017, and covering patients with primary GISTs of the duodenum was performed using modules from the SPSS package. Comparisons of treatment effects resulting from the administration of two differential methods of surgical treatment namely pancreaticoduodenectomy (PD), and limited resection (LR), were effected on the reports of the GIST patients thus selected.

RESULTS

Out of these 62 patients who had undergone resection of duodenal GISTs, 47 (76%) had limited resection (LR) and 15 (24%) underwent pancreaticoduodenectomy (PD). In Multivariate analyses, tumor size was an independent predictive factor for recurrence (p=0.008). ASA, tumor size, and PD were independent and significant prognostic factors on OS (p=0.021, p=0.024, and p=0.030, respectively). In the very low and low risk group, and high-risk group, there were no significant differences in the RFS (recurrence-free survival) and OS (overall survival) between the LR and PD groups.

CONCLUSIONS

When technically feasible, LR should be given due consideration as a reliable and curative option for duodenal GISTs achieving satisfactory RFS and OS.

Pre-surgical trial of the AKT inhibitor MK-2206 in patients with operable invasive breast cancer: a New York Cancer Consortium trial

INTRODUCTION

The PI3K/AKT/mTOR pathway is an oncogenic driver in breast cancer (BC). In this multi-center, pre-surgical study, we evaluated the tissue effects of the AKT inhibitor MK-2206 in women with stage I-III BC.

MATERIALS AND METHODS

Two doses of weekly oral MK2206 were administered at days - 9 and - 2 before surgery. The primary endpoint was reduction of pAktSer473 in breast tumor tissue from diagnostic biopsy to surgery. Secondary endpoints included changes in PI3K/AKT pathway tumor markers, tumor proliferation (ki-67), insulin growth factor pathway blood markers, pharmacokinetics (PK), genomics, and MK-2206 tolerability. Paired t tests were used to compare biomarker changes in pre- and post-MK-2206, and two-sample t tests to compare with prospectively accrued untreated controls.

RESULTS

Despite dose reductions, the trial was discontinued after 12 patients due to grade III rash, mucositis, and pruritus. While there was a trend to reduction in pAKT after MK-2206 (p = 0.06), there was no significant change compared to controls (n = 5, p = 0.65). After MK-2206, no significant changes in ki-67, pS6, PTEN, or stathmin were observed. There was no significant association between dose level and PK (p = 0.11). Compared to controls, MK-2206 significantly increased serum glucose (p = 0.02), insulin (p < 0.01), C-peptide (p < 0.01), and a trend in IGFBP-3 (p = 0.06).

CONCLUSION

While a trend to pAKT reduction after MK-2206 was observed, there was no significant change compared to controls. However, the accrued population was limited, due to toxicity being greater than expected. Pre-surgical trials can identify in vivo activity in the early drug development, but side effects must be considered in this healthy population.

Transient CHO expression platform for robust antibody production and its enhanced N-glycan sialylation on therapeutic glycoproteins

Large-scale transient expression in mammalian cells is a rapid protein production technology often used to shorten overall timelines for biotherapeutics drug discovery. In this study we demonstrate transient expression in a Chinese hamster ovary (CHO) host (ExpiCHO-S™) cell line capable of achieving high recombinant antibody expression titers, comparable to levels obtained using human embryonic kidney (HEK) 293 cells. For some antibodies, ExpiCHO-S™ cells generated protein materials with better titers and improved protein quality characteristics (i.e., less aggregation) than those from HEK293. Green fluorescent protein imaging data indicated that ExpiCHO-S™ displayed a delayed but prolonged transient protein expression process compared to HEK293. When therapeutic glycoproteins containing non-Fc N-linked glycans were expressed in transient ExpiCHO-S™, the glycan pattern was unexpectedly found to have few sialylated N-glycans, in contrast to glycans produced within a stable CHO expression system. To improve N-glycan sialylation in transient ExpiCHO-S™, we co-transfected galactosyltransferase and sialyltransferase genes along with the target genes, as well as supplemented the culture medium with glycan precursors. The authors have demonstrated that co-transfection of glycosyltransferases combined with medium addition of galactose and uridine led to increased sialylation content of N-glycans during transient ExpiCHO-S™ expression. These results have provided a scientific basis for developing a future transient CHO system with N-glycan compositions that are similar to those profiles obtained from stable CHO protein production systems. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2724, 2019.

Multiregion whole-exome sequencing of matched primary and metastatic tumors revealed genomic heterogeneity and suggested polyclonal seeding in colorectal cancer metastasis

Background

Distant metastasis accounts for 90% of deaths from colorectal cancer (CRC). Genomic heterogeneity has been reported in various solid malignancies, but remains largely under-explored in metastatic CRC tumors, especially in primary to metastatic tumor evolution.

Patients and methods

We conducted high-depth whole-exome sequencing in multiple regions of matched primary and metastatic CRC tumors. Using a total of 28 tumor, normal, and lymph node tissues, we analyzed inter- and intra-individual heterogeneity, inferred the tumor subclonal architectures, and depicted the subclonal evolutionary routes from primary to metastatic tumors.

Results

CRC has significant inter-individual but relatively limited intra-individual heterogeneity. Genomic landscapes were more similar within primary, metastatic, or lymph node tumors than across these types. Metastatic tumors exhibited less intratumor heterogeneity than primary tumors, indicating that single-region sequencing may be adequate to identify important metastasis mutations to guide treatment. Remarkably, all metastatic tumors inherited multiple genetically distinct subclones from primary tumors, supporting a possible polyclonal seeding mechanism for metastasis. Analysis of one patient with the trio samples of primary, metastatic, and lymph node tumors supported a mechanism of synchronous parallel dissemination from the primary to metastatic tumors that was not mediated through lymph nodes.

Conclusions

In CRC, metastatic tumors have different but less heterogeneous genomic landscapes than primary tumors. It is possible that CRC metastasis is, at least partly, mediated through a polyclonal seeding mechanism. These findings demonstrated the rationale and feasibility for identifying and targeting primary tumor-derived metastasis-potent subclones for the prediction, prevention, and treatment of CRC metastasis.

Abstract P4-11-05: Improving neoadjuvant breast cancer therapy rates uptake with education and technology

Background: Recent studies show that treating aggressive subtypes of breast cancer (BC) with neoadjuvant chemotherapy (NAC) improves clinical outcomes in addition to breast conservation therapy (BCT) rates. Yet a large multi-site population-level analysis shows that only 5.5% of NCCN-guideline eligible patients receive NAC (Ontilo et al, 2013). Multi-level interventions are needed to improve concordance with NCCN guidelines for NAC consideration in women who meet criteria for BCT (clinical stage IIA, IIB, and IIIA BC). Methods: A 2-part intervention was undertaken to improve adherence to NAC guidelines. Certified medical education (CME) was first provided on BC diagnostics and treatment (Tx), including NAC. Next patients were recruited to a point of care technology-based intervention. Eligibility included a new diagnosis of invasive BC, clinical stage T1c and/or N1 or greater, and no prior Tx. Patients interact with an electronic care planning system (CPS) at the time of surgical consultation to report preferences for decision-making and concerns, such as distress over losing a breast. The CPS displays these findings along with a draft care plan (CP) that suggests guideline based referrals and provides patient education about BC diagnosis and Tx options. After editing, surgeons finalize and deliver CPs at the visit. The goal is to describe referral rates to medical oncology for discussion of and receipt of NAC. Outcomes from chart abstraction are compared to historical rates in the literature and where available, the institution. Results: Data on 39 of 75 women are mature (remaining to be presented at meeting). Median age is 60 years (range 37-92) and clinical stage is IA=41% (N=16), IIA= 41% (N=16), IIB=8% (N=3), and III=10% (N=4). Of 39 patients, 44% were HR+HER2+, 10% were HR+HER2-, 13% had triple negative BC, and 33% had incomplete data. Per NCCN stage, 59% (N =23) were eligible for NAC evaluation. 96% (N=22) of those eligible were referred to MO. Follow up 2 months post-surgical appointment revealed 91% (N=21) of referred patients had completed a MO consultation. 39% (N=9) of those referred for evaluation (N=23) had a prescription for NAC and all prescriptions were guideline adherent, including regimens combining chemotherapy with trastuzumab and pertuzumab for HER2+ disease. Overall, 30.4% of women eligible for referral went on to receive NAC. Distress related to loss of breast was moderate (0-10 scale, M=4.83) and was significantly related to whether patients received a referral for NAC (B= -.304, Wald's=4.61, p=.03). Most of participating providers (80%, N=5) felt the CP was valuable to help with Tx decision-making. Conclusions: Preliminary results show CME and an electronic CPS may improve NAC uptake. Rates of prescription were clearly higher in this analysis than in a 4-center population database study, both overall (23.1% vs. 3.8%) and by NCCN eligibility (30.4% vs. 5.5%), and compared to baseline in 1 (of 3 planned) centers in the study who had a baseline rate of overall NAC prescription of 8.7% in the year prior to the study. The higher the distress over the loss of a breast, the more likely the patient received a referral for NAC. These data provide preliminary support for improving NAC uptake and warrant investigation in a RCT.

Citation Format: Gary M, Keeler V, Rush S, Parsons P, Zhong X, Stricker CT, Wujcik D, DiGiovanni L, Davis A, Han LK. Improving neoadjuvant breast cancer therapy rates uptake with education and technology [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-11-05.

Noninvasive Assessment of Intracranial Pressure Status in Idiopathic Intracranial Hypertension Using Displacement Encoding with Stimulated Echoes (DENSE) MRI: A Prospective Patient Study with Contemporaneous CSF Pressure Correlation

BACKGROUND AND PURPOSE

Intracranial pressure is estimated invasively by using lumbar puncture with CSF opening pressure measurement. This study evaluated displacement encoding with stimulated echoes (DENSE), an MR imaging technique highly sensitive to brain motion, as a noninvasive means of assessing intracranial pressure status.

MATERIALS AND METHODS

Nine patients with suspected elevated intracranial pressure and 9 healthy control subjects were included in this prospective study. Controls underwent DENSE MR imaging through the midsagittal brain. Patients underwent DENSE MR imaging followed immediately by lumbar puncture with opening pressure measurement, CSF removal, closing pressure measurement, and immediate repeat DENSE MR imaging. Phase-reconstructed images were processed producing displacement maps, and pontine displacement was calculated. Patient data were analyzed to determine the effects of measured pressure on pontine displacement. Patient and control data were analyzed to assess the effects of clinical status (pre-lumbar puncture, post-lumbar puncture, or control) on pontine displacement.

RESULTS

Patients demonstrated imaging findings suggesting chronically elevated intracranial pressure, whereas healthy control volunteers demonstrated no imaging abnormalities. All patients had elevated opening pressure (median, 36.0 cm water), decreased by the removal of CSF to a median closing pressure of 17.0 cm water. Patients pre-lumbar puncture had significantly smaller pontine displacement than they did post-lumbar puncture after CSF pressure reduction (P = .001) and compared with controls (P = .01). Post-lumbar puncture patients had statistically similar pontine displacements to controls. Measured CSF pressure in patients pre- and post-lumbar puncture correlated significantly with pontine displacement (r = 0.49; P = .04).

CONCLUSIONS

This study establishes a relationship between pontine displacement from DENSE MR imaging and measured pressure obtained contemporaneously by lumbar puncture, providing a method to noninvasively assess intracranial pressure status in idiopathic intracranial hypertension.

Role of levothyroxine and vitamin E supplementation in the treatment of oxidative stress-induced injury and apoptosis of myocardial cells in hypothyroid rats

OBJECTIVE

To explore the underlying mechanism and treatment of myocardial injury caused by hypothyroidism, we evaluated oxidative stress in serum and myocardial tissue of hypothyroid rats. The effect of levothyroxine (LT4) replacement therapy and vitamin E (VitE) supplementation on oxidative stress-induced injury and apoptosis of myocardial tissue is examined.

METHODS

Male Sprague-Dawley rats were divided into five groups: normal control group, propylthiouracil group (PTU group), LT4 treatment group (PTU + LT4 group), vitamin E treatment group (PTU + VitE group), and combined treatment group (PTU + LT4 + VitE group). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) expression in serum and myocardium were determined. Myocardial apoptosis index (AI) in each group was determined by TUNEL assay.

RESULTS

SOD levels in serum were significantly increased in PTU + VitE and PTU + LT4 + Vit E groups, as compared to that in PTU and PTU + LT4 groups (P < 0.05). MDA levels in serum and myocardial tissue were significantly lower in PTU + LT4, PTU + VitE, and PTU + LT4 + VitE groups, as compared to that in the PTU group (P < 0.05). Myocardial apoptosis was significantly increased in PTU and PTU + VitE groups as compared to that in the normal control group (P < 0.05), while it was significantly lower in PTU + LT4 and PTU + LT4 + VitE groups, as compared to that in the PTU group (P < 0.05).

CONCLUSION

In this study, levothyroxine replacement therapy and vitamin E supplementation appeared to ameliorate myocardial apoptosis in hypothyroid rats, the mechanism of which appears to be related to improved thyroid function and reduced oxidative stress.

Mechanistic understanding of the cysteine capping modifications of antibodies enables selective chemical engineering in live mammalian cells

Protein modifications by intricate cellular machineries often redesign the structure and function of existing proteins to impact biological networks. Disulfide bond formation between cysteine (Cys) pairs is one of the most common modifications found in extracellularly-destined proteins, key to maintaining protein structure. Unpaired surface cysteines on secreted mammalian proteins are also frequently found disulfide-bonded with free Cys or glutathione (GSH) in circulation or culture, the mechanism for which remains unknown. Here we report that these so-called Cys-capping modifications take place outside mammalian cells, not in the endoplasmic reticulum (ER) where oxidoreductase-mediated protein disulfide formation occurs. Unpaired surface cysteines of extracellularly-arrived proteins such as antibodies are uncapped upon secretion before undergoing disulfide exchange with cystine or oxidized GSH in culture medium. This observation has led to a feasible way to selectively modify the nucleophilic thiol side-chain of cell-surface or extracellular proteins in live mammalian cells, by applying electrophiles with a chemical handle directly into culture medium. These findings provide potentially an effective approach for improving therapeutic conjugates and probing biological systems.

Development of Fluorophore-Labeled Thailanstatin Antibody-Drug Conjugates for Cellular Trafficking Studies

As the antibody-drug conjugate (ADC) field grows increasingly important for cancer treatment, it is vital for researchers to establish a firm understanding of how ADCs function at the molecular level. To gain insight into ADC uptake, trafficking, and catabolism-processes that are critical to ADC efficacy and toxicity-imaging studies have been performed with fluorophore-labeled conjugates. However, such labels may alter the properties and behavior of the ADC under investigation. As an alternative approach, we present here the development of a "clickable" ADC bearing an azide-functionalized linker-payload (LP) poised for "click" reaction with alkyne fluorophores; the azide group represents a significantly smaller structural perturbation to the LP than most fluorophores. Notably, the clickable ADC shows excellent potency in target-expressing cells, whereas the fluorophore-labeled product ADC suffers from a significant loss of activity, underscoring the impact of the label itself on the payload. Live-cell confocal microscopy reveals robust uptake of the clickable ADC, which reacts selectively in situ with a derivatized fluorescent label. Time-course trafficking studies show greater and more rapid net internalization of the ADCs than the parent antibody. More generally, the application of chemical biology tools to the study of ADCs should improve our understanding of how ADCs are processed in biological systems.

Abstract P4-01-06: Diffuse optical tomography can predict pathologic complete response in patients with HER2+ or triple negative breast cancer undergoing neoadjuvant chemotherapy

Background

Pathologic complete response (pCR) predicts clinical outcome in women who receive neoadjuvant chemotherapy (NACT) for breast cancer. Identifying who will have a pCR early during NACT has the potential to save patients months of ineffective chemotherapy and limit unnecessary toxicity; however, no method currently is standardly used. Diffuse optical tomography (DOT) uses near-infrared light to measure concentrations of oxyhemoglobin [HbO2], deoxyhemoglobin [Hb], total hemoglobin [HbT], and oxygen saturation [SO2%], and can assess tissue structure and vascularity. As it is inexpensive, fast, and does not require radiation or intravenous contrast no radiation nor IV contrast, DOT has the potential to become an integral part of NACT to predict responses to NACT. Given the particular significance for pCR in HER2+ and triple negative breast cancer (TNBC), we prospectively evaluated whether a 2 week change in DOT parameters could predict pCR after 5 months of NACT in these subtypes.

Methods

We conducted a prospective cohort study of women with stage II-IIIC breast cancer scheduled to receive NACT with 12 weeks of weekly taxol and four cycles of doxorubicin with cyclophosphamide (AC). We evaluated the associations between residual cancer burden (RCB: 0-3; pCR= RCB 0) and changes in DOT measures. Optical imaging was performed at baseline and before the following: Taxol #3, Taxol #5, AC #1, AC #2, and surgery. Correlation and t-testing were used to evaluate the relationship between 2-week DOT changes and pathologic response.

Results

In a prospectively accrued, longitudinal clinical study with DOT, at least 20 patients with HER2+ or TNBC were enrolled. For patients with these tumor subtypes, there was a significant association between pCR after 5 months of NACT (i.e. RCB 0) and change in the following DOT parameters comparing baseline to after 2 weeks of taxol: HBO (p=0.02), HBT (p=0.02), and S02% (p=0.03). No significant association was seen with HB (p=0.20) or water (p=0.85). When looking specifically at patients with TNBC (n=at least 8 patients), these associations were particulars strong between pCR and the following DOT parameters: HBO (p=0.004), HBT (p=0.009), and S02% (p=0.04). Additional patients are anticipated in this study are anticipated to complete NACT and will be reported at SABCS.

Conclusions

Optical imaging can provide imaging biomarkers to monitor breast cancer response to NACT. Early predictions of pathologic response to NACT can be made with high accuracy as early as two weeks after treatment initiation. These findings are specifically strong in TNBC, a group for whom pCR is predictive of clinical outcome.

Citation Format: Kalinsky K, Lee S, Zhong X, Lim EA, Gunther JE, Hibshoosh H, Kim HK, Accordino M, Crew K, Hielscher A, Hershman DL. Diffuse optical tomography can predict pathologic complete response in patients with HER2+ or triple negative breast cancer undergoing neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-01-06.

Protein interaction networks at the host-microbe interface in Diaphorina citri, the insect vector of the citrus greening pathogen

The Asian citrus psyllid (Diaphorina citri) is the insect vector responsible for the worldwide spread of 'Candidatus Liberibacter asiaticus' (CLas), the bacterial pathogen associated with citrus greening disease. Developmental changes in the insect vector impact pathogen transmission, such that D. citri transmission of CLas is more efficient when bacteria are acquired by nymphs when compared with adults. We hypothesize that expression changes in the D. citri immune system and commensal microbiota occur during development and regulate vector competency. In support of this hypothesis, more proteins, with greater fold changes, were differentially expressed in response to CLas in adults when compared with nymphs, including insect proteins involved in bacterial adhesion and immunity. Compared with nymphs, adult insects had a higher titre of CLas and the bacterial endosymbionts Wolbachia, Profftella and Carsonella. All Wolbachia and Profftella proteins differentially expressed between nymphs and adults are upregulated in adults, while most differentially expressed Carsonella proteins are upregulated in nymphs. Discovery of protein interaction networks has broad applicability to the study of host-microbe relationships. Using protein interaction reporter technology, a D. citri haemocyanin protein highly upregulated in response to CLas was found to physically interact with the CLas coenzyme A (CoA) biosynthesis enzyme phosphopantothenoylcysteine synthetase/decarboxylase. CLas pantothenate kinase, which catalyses the rate-limiting step of CoA biosynthesis, was found to interact with a D. citri myosin protein. Two Carsonella enzymes involved in histidine and tryptophan biosynthesis were found to physically interact with D. citri proteins. These co-evolved protein interaction networks at the host-microbe interface are highly specific targets for controlling the insect vector responsible for the spread of citrus greening.

Human parvovirus B19 infection induced pure red cell aplasia in liver transplant recipients

AIM

Th aim of this study was to explore the diagnosis and treatment of pure red cell aplasia (PRCA) induced by human parvovirus B19 (HPV B19) infection in liver transplant recipients.

METHODS

We described and analysed the clinical manifestation, diagnosis, treatment and prognosis of the 13 liver transplant recipients confirmed to have PRCA induced by HPV B19.

RESULTS

In the past 3 years, 13 liver transplant recipients out of a cohort of 570 recipients were confirmed to have PRCA induced by HPV B19. Some experienced fever (eight patients) but all of the patients had a gradual decline of haemoglobin levels within 2 months posttransplantation. The diagnosis was confirmed by several tests including bone marrow aspiration and polymerase chain reaction (PCR) assays. All recipients achieved remission using symptomatic treatment that included intravenous immunoglobulins (IVIG), immunosuppressive regimen switch and blood transfusion.

CONCLUSION

Pure red cell aplasia induced by HPV B19 infection is a disease with a favourable prognosis after symptomatic and supportive treatment. (i) Pure red cell aplasia anaemia is a prominent clinical sign of HPV B19 infection in liver transplant recipients. (ii) PCR technology combined with bone marrow aspiration and other laboratory examinations will meet the requirement for the diagnosis and suggests that the differential diagnosis includes PRCA and graft versus host disease (GVHD). (iii) IVIG is recommended as the first regimen for the treatment of PRCA induced by HPV B19 infection in liver transplant recipients. IVIG can be repeated if the patient has a relapse. (iv) A switch of the baseline immunosuppressive regimen may achieve a favourable curative effect.

[The correlation between cerebral MRI characteristics of posterior reversible encephalopathy syndrome and serum levels of PlGF, sEng in patients with pre-eclampsia]

Objective: To investigate the MRI characteristics of posterior reversible encephalopathy syndrome (PRES) in patients with pre-eclampsia(PE) and its correlation with serum placental growth factor (PlGF), soluble endoglin (sEng) and sEng/PlGF ratio. Methods: 34 patients with PE who were admitted to Guangdong Women and Children Hospital from September 2013 to March 2014 were studied retrospectively.13 cases had PRES and 21 cases had normal cerebral MRI. All patients underwent conventional MRI and DWI scanning. The score of brain edema (SBE) were calculated. PlGF, sEng concentrations were measured with ELISA. The levels of PlGF, sEng and sEng/PlGF were compared between the PRES group and the normal MRI groups. The correlation of sEng/PIGF ratio and SBE were studied as well. Results: The PlGF in the PRSE group was (231.4±66.8) ng/L, and in normal cerebral MRI group was (333.6±37.5) ng/L (t= 5.61, P<0.05). The sEng in the PRSE group was (5 256.2±879.6) ng/L, in normal cerebral MRI group was (3 955.6±537.7) ng/L (t=6.53, P<0.01).The sEng/PlGF in the PRSE group was (26.0±10.0) , and in normal cerebral MRI group was (11.9±1.6; t=8.41, P<0.01) , with the cut-off value of 20.0. The sensitivity was 81.8% and the specificity was 85.0%.There was no statistically significant correlation between PlGF, sEng and SBE (P>0.05).There was a positive correlation between the sEng/PlGF ratio and SBE (P>0.05). Conclusion: The value of sEng/PlGF ratio was correlated with brain edema score in PE. The serum sEng/PlGF ratio may be used as a reference for prediction of PRES.

A meta-analysis of reflectance confocal microscopy for the diagnosis of malignant skin tumours

Early diagnosis is extremely important for treatment and prognosis of skin cancer. Reflectance confocal microscopy (RCM) is a recently developed technique used to diagnose skin cancer. This meta-analysis was carried out to assess the accuracy of RCM for the diagnosis of malignant skin tumours. We conducted a systematic literature search of EMBASE, PubMed, the Cochrane Library and Web of Science database for relevant articles in English published up to 24 December 2015. The quality of the included studies was assessed using the QUADAS-2 tool. Statistical analyses were conducted using the software Meta-Disc version 1.4 and STATA version 12.0. A total of 21 studies involving 3108 patients with a total of 3602 lesions were included in the per-lesion analysis. The corresponding pooled results for sensitivity and specificity were 93.6% (95% CI: 0.92-0.95) and 82.7% (95% CI: 0.81-0.84) respectively. Positive likelihood ratio and negative likelihood ratio were 5.84 (95% CI: 4.27-7.98) and 0.08 (95% CI: 0.07-0.10) respectively. Subgroup analysis showed that RCM had a sensitivity of 92.7% (95% CI: 0.90-0.95) and a specificity of 78.3% (95% CI: 0.76-0.81) for detecting melanoma. The pooled sensitivity and specificity of RCM for detecting basal cell carcinoma were 91.7% (95% CI: 0.87-0.95) and 91.3% (95% CI: 0.94-0.96) respectively. RCM is a valid method of identifying malignant skin tumours accurately.