Bi-allelic Mutations in TTC21A Induce Asthenoteratospermia in Humans and Mice

Male infertility is a major concern affecting human reproductive health. Asthenoteratospermia can cause male infertility through reduced motility and abnormal morphology of spermatozoa. Several genes, including DNAH1 and some CFAP family members, are involved in multiple morphological abnormalities of the sperm flagella (MMAF). However, these known genes only account for approximately 60% of human MMAF cases. Here, we conducted further genetic analyses by using whole-exome sequencing in a cohort of 65 Han Chinese men with MMAF. Intriguingly, bi-allelic mutations of TTC21A (tetratricopeptide repeat domain 21A) were identified in three (5%) unrelated, MMAF-affected men, including two with homozygous stop-gain mutations and one with compound heterozygous mutations of TTC21A. Notably, these men consistently presented with MMAF and additional abnormalities of sperm head-tail conjunction. Furthermore, a homozygous TTC21A splicing mutation was identified in two Tunisian cases from an independent MMAF cohort. TTC21A is preferentially expressed in the testis and encodes an intraflagellar transport (IFT)-associated protein that possesses several tetratricopeptide repeat domains that perform functions crucial for ciliary function. To further investigate the potential roles of TTC21A in spermatogenesis, we generated Ttc21a mutant mice by using CRISPR-Cas9 technology and revealed sperm structural defects of the flagella and the connecting piece. Our consistent observations across human populations and in the mouse model strongly support the notion that bi-allelic mutations in TTC21A can induce asthenoteratospermia with defects of the sperm flagella and head-tail conjunction.

Do repeat ultrasounds affect orchiectomy rate in patients with testicular torsion treated at a pediatric institution?

INTRODUCTION

Testicular torsion is a urological emergency; as the testicular salvage rate decreases with time, prompt intervention is required to restore the blood flow. Interhospital transfers and ultrasound examinations, while clinically essential to proper treatment and diagnosis, may adversely affect outcomes by delaying surgical intervention. Patients transferred to another institution for treatment of testicular torsion may experience a further time delay by undergoing two ultrasound examinations: one at the initial admitting institution and one at the receiving institution. To the knowledge of the authors, no study has yet explored the time delays and outcomes associated with these repeat ultrasounds.

OBJECTIVE

The objective was to investigate the impact of repeat ultrasound imaging on time to treatment and patient outcomes in patients with testicular torsion.

STUDY DESIGN

A retrospective chart review of 133 patients, aged 0-20 years, treated at the authors' institution for testicular torsion was conducted. Neonate patients and patients who did not receive ultrasound were excluded. Demographic and clinical variables were collected from the electronic medical record. Pearson Chi-squared and t-tests were used for univariate comparisons, and multivariate logistic regression analysis was performed to measure the relationships between variables.

RESULTS

Forty-nine percent of patients were primary patients, and 51% were transfer patients. Fifty-two percent of transfer patients received repeat ultrasounds. In comparison to salvaged patients, those who underwent orchiectomy experienced a greater delay between presentation at the institution and surgical intervention (229 min vs 177 min, p = 0.048). The transfer status does not appear to be related to the outcome, i.e. orchiectomy versus salvage. Patients who underwent orchiectomy were more likely than salvaged patients to have received repeat ultrasounds (p = 0.008). Repeat ultrasound patients had three times the likelihood of orchiectomy of single ultrasound patients. In a subset analysis of transfer patients, repeat ultrasound patients were more likely than single ultrasound patients to receive an orchiectomy (p = 0.03).

DISCUSSION

In agreement with previous studies, patients who underwent orchiectomy were found to experience greater treatment delays and trend toward transfer. Specifically, repeat ultrasound and time between presentation and intervention appear to influence patient outcomes. The effect of repeat ultrasound on outcomes appears to be independent of the transfer status. The study was limited by its retrospective nature and small sample size.

CONCLUSION

The analysis suggests that efforts to prevent repeat ultrasounds and minimize the time between presentation and intervention would improve patient outcomes. It is proposed that standardized clinical decision-making procedures, such as the TWIST scoring system, be incorporated into hospital protocols.

Novel homozygous nonsense mutations in LHCGR lead to empty follicle syndrome and 46, XY disorder of sex development

Empty follicle syndrome (EFS) is a disorder associated with female infertility and presents as a complete failure to retrieve oocytes during ART cycles despite normal follicle development and careful aspiration. To date, only two EFS cases have been reported with homozygous missense mutations in the luteinizing hormone/chorionic gonadotropin receptor (LHCGR) gene, and both cases showed normal estradiol (E2) production during ovulation induction. The molecular genetic mechanisms of EFS remain unknown. Herein, we report two novel homozygous inactivating LHCGR mutations, c.736 C>T (p.Q246*) and c.846dupT (p.R283*), in two female EFS patients from unrelated consanguineous families. The probands had impaired E2 production during the ART process, which differs from previously reported EFS cases. The inactivating mutations not only led to EFS in the two female probands, but also resulted in 46, XY disorder of sex development (46, XY DSD) in their male siblings. As far as we know, this is the first report of LHCGR mutations leading to both EFS and 46, XY DSD within the same pedigree. Our findings provide researchers and clinicians with a better understanding of phenotype-genotype correlations between EFS and 46, XY DSD and the LHCGR gene.

Intervals between bone mineral density testing with dual-energy X-ray absorptiometry scans in clinical practice

Intervals between dual-energy X-ray absorptiometry (DXA) scans were evaluated in a large cohort of typical clinical practice. Intensive DXA scanning (intervals < 23 months) decreased substantially, from 16.7% in 2006 to 6.7% in 2015.

INTRODUCTION

Serial dual-energy X-ray absorptiometry (DXA) measurements are suggested for patients at high risk of fractures. However, little is known about how often DXA testing occurs in clinical practice.

METHODS

We examined time intervals between DXA testing for monitoring purpose at two academic medical centers in the US between 2004 and 2017. The primary outcome was the presence of testing intervals < 23 months (termed "intensive DXA testing"). A generalized linear mixed model was used to evaluate the association between selected patient-level clinical factors and intensive DXA testing.

RESULTS

Forty-nine thousand four hundred ninety-four DXA tests from 20,200 patients were analyzed. The mean time interval between scans was 36 ± 21 months. Only 11.1% of the repeated DXA testing met the criterion for intensive testing. The percentage of intensive DXA testing dropped from 16.7% in 2006 to 6.7% in 2015 (p for trend < 0.001). After adjusting for age, gender, number of outpatient visits, and calendar year, correlates of intensive DXA testing included a baseline T-score < -2.5 at any anatomic site (OR, 4.8; 95%CI, 4.0-5.7), active use of drugs for osteoporosis (OR, 1.6; 95%CI, 1.3-1.9), and active use of glucocorticoids (OR, 1.3; 95%CI, 1.2-1.4).

CONCLUSIONS

The predictors of intensive DXA testing suggest that this practice is used preferentially in patients with multiple risk factors and to monitor the response to pharmacotherapy. However, intensive DXA testing has become less common in real-world clinical practice over the last decade. Further studies are required to better define the optimal use of bone mineral density testing in this vulnerable population.

[Effect of umbilical cord mesenchymal stem cells on biological characteristics of esophageal cancer EC1 cells]

Objective: To investigate the effects of human umbilical cord mesenchymal stem cells (MSCs) on the proliferation, apoptosis, migration, invasion and stemness of esophageal cancer EC1 cells. Methods: Human umbilical cord mesenchymal stem cells were isolated and cultured in vitro, and cell phenotype was identified by flow cytometry. MSCs or their conditioned medium were co-cultured with esophageal cancer EC1 cells. The effects on the proliferation, apoptosis, migration, invasion and stemness of EC1 cells were examined by cell counting kit-8 (CCK-8), flow cytometry, Transwell, quantitative real-time polymerase chain reaction (RT-qPCR) and spheroid formation assays. Results: MSCs inhibited the proliferation of EC1 cells in a concentration dependent manner. When the ratio of MSCs to EC1 cells was 0∶1, 1∶1, 2∶1, 5∶1, the apoptotic rates of EC1 cells were (4.07±0.34)%, (8.90±0.36)%, (10.80±0.50)% and (15.23±1.06)%, respectively, suggesting that MSCs promoted the apoptosis of EC1 cells in a concentration dependent manner (all P<0.05). The expression levels of OCT2, SOX2, KLF4, CXCR4 and CXCR7 in EC1 cells cultured in 80% conditioned medium were 0.53±0.03, 0.49±0.02, 0.73±0.09, 0.57±0.05 and 0.24±0.02, respectively, which were lower than those in the regular medium group (all P<0.05). The numbers of migrated cells in regular medium as well as 10%, 40%, and 80% conditioned medium were 287.3±21.6, 280.7±15.5, 264.3±16.8, and 257.7±8.0, respectively. Meanwhile, the numbers of invasive cells were 194.3±16.6, 213.7±24.3, 221.0±16.0, (252.0±20.4), respectively. There was no significant difference between the groups (all P>0.05). Conclusion: Human umbilical cord mesenchymal stem cells can inhibit the proliferation, promote apoptosis and reduce the stemness, and have no significant effect on the migration and invasion of EC1 cells.

Humanin levels in human seminal plasma and spermatozoa are related to sperm quality

BACKGROUND

Humanin has reportedly been expressed in testis and spermatozoa, but no study has yet reported its presence in human seminal plasma (SP).

OBJECTIVE

The aim of this study was to investigate the presence of humanin in human SP and to determine the correlation between humanin levels in SP/spermatozoa and sperm quality.

MATERIALS AND METHODS

Semen samples for SP/sperm humanin level measurement were collected from 164 patients who attended our andrology clinic for fertility evaluation. The localization of humanin in spermatozoa was evaluated using an immunofluorescence method, and SP/sperm humanin levels were measured with ELISA. Correlations between SP/sperm humanin levels and sperm parameters were analyzed.

RESULTS

Humanin was expressed in the midpiece of the spermatozoa. Humanin concentrations in the SP ranged from 24.4 to 285.1 pg/mL, with a median of 89.7 pg/mL. The SP humanin concentrations in patients with normospermia were significantly higher than those in patients with oligospermia (p < 0.001), asthenospermia (p = 0.002), and oligoasthenospermia (p < 0.001). Spearman analysis showed a positive and significant correlation between SP humanin concentration and sperm concentration (r = 0.75, p < 0.001), and progressive sperm motility (r = 0.29, p < 0.001). Sperm humanin level was significantly and positively associated with progressive sperm motility (r = 0.70, p < 0.001). In addition, a significantly higher level of humanin was found in swim-up spermatozoa than in non-swim-up spermatozoa (p = 0.03).

CONCLUSIONS

Seminal plasma and sperm humanin levels were significantly and positively correlated with sperm quality, especially sperm motility. Further studies of the origin of SP humanin and its role in spermatogenesis should be conducted.

Low levels of pyruvate induced by a positive feedback loop protects cholangiocarcinoma cells from apoptosis

BACKGROUND

Cancer cells avidly consume glucose and convert it to lactate, resulting in a low pyruvate level. This phenomenon is known as the Warburg effect, and is important for cell proliferation. Although cMyc has often been described as an oncoprotein that preferentially contributes to the Warburg effect and tumor proliferation, mechanisms of action remain unclear. Histone deacetylase 3 (HDAC3) regulates gene expression by removing acetyl groups from lysine residues, as well as has an oncogenic role in apoptosis and contributes to the proliferation of many cancer cells including cholangiocarcinoma (CCA). HDAC inhibitors display antitumor activity in many cancer cell lines. Cancer cells maintain low levels of pyruvate to prevent inhibition of HDAC but the mechanisms remain elusive. The purpose of our study was to explore the role of cMyc in regulating pyruvate metabolism, as well as to investigate whether the inhibitory effect of pyruvate on HDAC3 could hold promise in the treatment of cancer cells.

METHODS

We studied pyruvate levels in CCA cell lines using metabolite analysis, and analyzed the relationship of pyruvate levels and cell proliferation with cell viability analysis. We cultivated CCA cell lines with high or low levels of pyruvate, and then analyzed the protein levels of HDAC3 and apoptotic markers via Western Blotting. We then explored the reasons of low levels of pyruvate by using seahorse analysis and 13C6 metabolites tracing analysis, and then confirmed the results using patient tissue protein samples through Western Blotting. Bioinformatics analysis and transfection assay were used to confirm the upstream target of the low levels of pyruvate status in CCA. The regulation of cMyc by HDAC3 was studied through immunoprecipitation and Western Blotting.

RESULTS

We confirmed downregulated pyruvate levels in CCA, and defined that high pyruvate levels correlated with reduced cell proliferation levels. Downregulated pyruvate levels decreased the inhibition to HDAC3 and consequently protected CCA cells from apoptosis. Synergistically upregulated LDHA, PKM2 levels resulted in low levels of pyruvate, as well as poor patient survival. We also found that low levels of pyruvate contributed to proliferation of CCA cells and confirmed that the upstream target is cMyc. Conversely, high activity of HDAC3 stabilized cMyc protein by preferential deacetylating cMyc at K323 site, which further contributed to the low pyruvate levels. Finally, this creates a positive feedback loop that maintained the low levels of pyruvate and promoted CCA proliferation.

CONCLUSIONS

Collectively, our findings identify a role for promoting the low pyruvate levels regulated by c-Myc, and its dynamic acetylation in cancer cell proliferation. These targets, as markers for predicting tumor proliferation in patients undergoing clinical treatments, could pave the way towards personalized therapies.

Structural and electrical characterization of monolithic core-double shell n-GaN/Al/p-AlGaN nanowire heterostructures grown by molecular beam epitaxy

We have studied the epitaxy and structural characterization of monolithic n-GaN/Al/p-AlGaN nanowire heterostructures. It is found that high quality, nearly defect free, full shell epitaxial Al can be grown in situ on Al(Ga)N nanowires and vice versa. Detailed scanning transmission electron microscopy (STEM), high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) suggest that the Al (111) plane maintains an epitaxial relationship with Al(Ga)N (0001) in the nanowire growth direction. Full ultraviolet composition range (340 nm-210 nm) Al/Al(Ga)N core-double shell nanowire backward diode characteristics were investigated. We have demonstrated a monolithic n⁺⁺-GaN/Al/p⁺⁺-Al(Ga)N nanowire backward diode, wherein an epitaxial Al layer serves as the tunnel junction. Such an Al(Ga)N-based n-p-n nanowire backward diode exhibits record low resistivity (<1.5 × 10^-4Ω cm²) and a low turn-on voltage of ∼2.7 V.

[Diagnostic and therapeutic values of interphase fluorescence in situ hybridization in B-cell lymphomas: a clinicopathologic analysis of 604 cases]

Objective: To investigate the feasibility and value of interphase fluorescence in situ hybridization (FISH) in the pathological diagnosis, differential diagnosis and therapeutic assessment of B-cell lymphomas. Methods: The cohort included 604 cases of B-cell lymphoma which were collected at West China Hospital from May 2010 to December 2016.And all were subjected to interphase FISH using 11 break apart or fusion probes (MYC, bcl-2, bcl-6, IRF4, MYC/IgH, bcl-2/IgH, CCND1/IgH, IgH, API2/MALT1, p53/ATM, and D13S319/CEP12). Results: The median age of the 604 B-cell lymphoma patients was 47.7 (aged 2-90) years including 372 men and 232 women. All the cases was divided into 463 large B cell lymphomas(LBL) and 141 small B cell lymphomas, and the total interphase FISH positive rate was 59.8% (361/604). Among the 463 LBL, 12.5% (58/463), 9.5% (44/463) and 2.2% (10/463) of cases showed MYC, bcl-6 and bcl-2 gene rearrangements respectively; and 363 diffuse large B cell lymphoma (DLBCLs) were reclassified as germinal center B-cell (GCB) subtype (38.6%, 140/363) and non-GCB subtype (61.4%, 223/363) by Hans algorithm. The rearrangement rates in GCB and non-GCB DLBCL were 45.7%(64/140)and 21.5%(48/223; P=0.001), respectively. Compared to the non-GCB DLBCL, GCB DLBCL showed higher MYC and bcl-2 gene rearrangements (P=0.001). Eleven (2.4%, 11/463) cases had MYC and bcl-6 or bcl-2 gene rearrangement (double-hit lymphoma); one (0.2%, 1/463) case had MYC, bcl-6 and bcl-2 gene rearrangements (triple-hit lymphoma); two (0.4%, 2/463) cases had bcl-2 and bcl-6 gene rearrangements. MYC translocation and MYC/IgH fusion were detected in 94.2%(81/86) and 83.7%(72/86) cases of Burkitt lymphomas. IRF4 rearrangement was detected in two cases of IRF4+ LBCL. Genetic abnormalities were detected in 9/19, 100%(29/29), 30.8%(12/39) and 68.5%(37/54) cases of follicular lymphoma, mantle cell lymphoma, MALT lymphoma and chronic lymphocytic leukemia, respectively. Conclusions: Interphase FISH can rapidly and accurately detect the genetic changes in B-cell lymphomas. Different genetic changes are specifically valuable to the diagnosis, differential diagnosis, prognosis evaluation and treatment guidance of various B-cell lymphomas.

An electrically injected AlGaN nanowire defect-free photonic crystal ultraviolet laser

We report on the demonstration of an electrically injected AlGaN nanowire photonic crystal laser that can operate in the ultraviolet spectral range. The nanowire heterostructures were grown on sapphire substrate using a site-controlled selective area growth process. By exploiting the topological high-Q resonance of a defect-free nanowire photonic crystal, we have demonstrated electrically pumped lasers that can operate at 369.5 nm with a relatively low threshold current density of ~2.1 kA/cm² under continuous wave operation at room-temperature. This work provides a promising approach for achieving low threshold semiconductor laser diodes operating in the UV spectral range that were previously difficult.

Abstract P3-08-11: Multi-omics profiling reveals distinct molecular features in young and elderly triple negative breast cancer

Purpose

Age at breast cancer diagnosis not only predicts clinical outcome, but also indicates distinct molecular features thus we can choose the most appropriate treatment strategies. Yet little is known about the molecular profile of young and elderly triple negative breast cancers (TNBCs).

Methods

Clinical, genomic and transcriptome features of young (&lt;40 year-olds) and elderly (≥65 year-olds) TNBC patients were studied in a cohort of 473 TNBCs from Fudan University Shanghai Cancer Center.

Results

In this study, 50, 354 and 69 patients were &lt;40, 40–64 and ≥65 years of age, respectively. Young TNBCs had more relapse or metastasis within the first 2 years after surgery (P=0.036) which was also significant in the basal-like subgroup (P=0.004), while elderly TNBCs were more likely to be luminal androgen receptor (LAR) subtype (46%) harboring frequent PIK3CA and KMT2C/KMT2D somatic mutations, with more fibrosis or mesenchymal-like (MES) subtype (in the basal-like subgroup) and featured by significantly lower Ki-67 index. Gene set enrichment analyses revealed that young TNBCs showed elevated expression of genes involved in cell cycle, nucleotide metabolism and DNA damage repair. In further discussion on nucleotide metabolism, TYMS, a crucial gene encoding thymidylate synthase while is also the target of fluorouracil and capecitabine, were identified to be enriched in young TNBCs independent of molecular subtype in both our cohort (adjusted P&lt;0.001) and METABRIC (adjusted P=0.027). We next studied DNA damage features and found that while TNBCs of different age groups had comparable somatic mutation load, their mutations had distinct generation mechanism that homologous recombination deficiency (HRD) related signature and Aging related signature tend to be enriched in younger and elder patients, respectively. We also observed higher germline BRCA1 mutation rate in young TNBCs (23%). Interestingly, while germline BRCA2 mutation rate was comparable among the groups, copy number (CN) loss of Chr13q13 (with BRCA2 in the 'peak') was almost exclusively found in young patients (adjusted P&lt;0.05). We also found enriched CN loss at Chr15q13 (with FAN1 in the 'peak') and CN amplification at Chr1p34 (with KDM4A in the 'peak') in young patients. These two events significantly affected the expression levels of FAN1 and KDM4A, respectively, and were both corrected with genomic based HRD indexes.

Conclusions

TNBCs of different age had distinct clinical and molecular features. We should pay attention to that nearly half of the TNBCs diagnosed at 65 years-old or later were not basal-like cancers but a special group with positive AR staining. Taking together with the higher fibrosis/MES proportion in elderly TNBC, we should reconsider the benefit of specific treatment strategies (like neoadjuvant chemotherapy) in these patients. The young TNBCs were characterized by activated cell cycle, elevated nucleotide metabolism (especially TYMS expression and corresponding pyrimidine metabolism) and enhanced DNA damage (especially HRD). These molecular features supported the aggressive phenotypes of young TNBC, while also provide us with potential therapeutic strategies.

Citation Format: Ma D, Jiang Y-Z, Xie M-D, Xiao Y, Zhao S, Shao Z-M. Multi-omics profiling reveals distinct molecular features in young and elderly triple negative breast cancer [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 P3-08-11.

Abstract P4-06-24: Microenvironment heterogeneity of triple-negative breast cancer reveals distinct immune escape mechanisms and potential driver events

Background The microenvironment phenotypes strongly affect the immunotherapeutic strategies for triple-negative breast cancer (TNBC). Although the multi-omics profile of TNBC has been comprehensively characterized, few studies have focused on the microenvironment phenotypes of TNBC.

Methods With multi-omics data for the largest single-center TNBC cohort (n=386), we first established a TNBC-specific microenvironment cell signature. We further used single sample gene set enrichment analysis to calculate the relative number of microenvironment cell subsets in each sample. Then, we performed k-means clustering to classify the TNBC microenvironment phenotypes into heterogeneous clusters. Furthermore, we systematically analyzed the extrinsic and intrinsic immune escape mechanisms of different TNBC microenvironment clusters. In addition, we explored genomic alterations that might decrease immune infiltration in certain TNBC microenvironment clusters.

Results We classified the TNBC microenvironment phenotypes into three heterogeneous clusters. Cluster 1 (type 1 “cold tumor”) had low microenvironment cells infiltration. Cluster 2 (type 2 “cold tumor”) was characterized by resting innate immune cells, fibroblasts and endothelial cells infiltration. Cluster 3 (“hot tumor”) was featured by adaptive immune cells infiltration. Analysis of immune escape mechanism revealed that an incapability to attract innate immune cells (resulting in failure of adaptive immunity) led to immune escape of cluster 1. The chemotaxis but inactivation of innate immunity (also leading to failure of adaptive immunity) and low tumor antigen burden resulted in immune escape of cluster 2. High expression of immune checkpoint molecules contributed to immune escape of cluster 3. In addition, we found that tumor infiltrating lymphocytes (TILs) were positively correlated with immune checkpoint molecules expression, while mutation load was negatively correlated with those indicators in triple-negative breast cancer. Analysis of enrichment pathways, mutations and somatic copy number variations between the “cold tumor” and “hot tumor” clusters revealed that amplification of MYC and activation of MYC-related pathways might decrease the immune infiltration of cluster 1. Mutations in PI3K-AKT pathway members and activation of fibroblasts-related pathways might decrease the immune infiltration of cluster 2.

Conclusion Utilizing the largest single-center TNBC cohort with multi-omics data, our study first revealed the heterogeneity of the TNBC microenvironment, with translational significance both clinically and biologically. First, we identified a subtype of “hot tumor” in TNBC (cluster 3), for which immune checkpoint blockers (ICBs) might be effective. TILs and immune checkpoint molecules expression but not mutation load might predict the efficacy of ICBs. Second, we presumed some genomic alterations that might drive “cold tumor” formation in TNBC. Our study represents a step toward personalized immunotherapy for TNBC patients.

Key Words triple-negative breast cancer, multi-omics, microenvironment heterogeneity, immune escape

Citation Format: Xiao Y, Ma D, Zhao S, Jiang Y-Z, Shao Z-M. Microenvironment heterogeneity of triple-negative breast cancer reveals distinct immune escape mechanisms and potential driver events [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 P4-06-24.

Abstract P3-07-12: Identification of luminal A-like subgroup among ER+/PR+/HER2+ breast cancers and its clinical implications

Background Triple positive breast cancers (TPBCs), i.e. estrogen receptor-positive (ER+)/ progesterone receptor-positive (PR+)/ human epidermal growth factor receptor 2-positive (HER2+) breast cancers, constitute a therapeutic challenge due to the functional crosstalk between the hormone receptors and HER2 pathways. The intrinsic molecular subtyping of TPBCs has rarely been studied and may have implications for the prognostic evaluation and therapeutic decision-making.

Methods Our study included four cohorts of patients with TPBC. The first one consisted of 82 patients from The Cancer Genome Atlas (TCGA). The second and third ones were from two publicly available microarray datasets (GSE2603 and GSE2109) and included 37 and 30 patients respectively. The forth one comprised 165 patients from Fudan University Shanghai Cancer Center. First, we examined the PAM50 intrinsic subtypes of TPBCs in the first three cohorts. Then, we tried to find several differentially expressed genes (DEGs) between luminal A and the other subtypes. In cohort 1, we identified DEGs using LIMMA. In cohort 2 and 3, we further filtered and validated them using Wilcoxon's rank sum test. We also performed Receiver operating characteristic analyses to evaluate the accuracy of candidate DEGs in identifying TPBCs of luminal A subtype and determined the top 3 DEGs according to the area under the curve. Finally, in cohort 4, we detected the expression of these 3 genes by immunohistochemical (IHC) staining of tissue sections, defined a group of luminal A-like TPBCs and examined the prognosis and effect of adjuvant trastuzumab for them.

Results The distribution of PAM50 intrinsic subtypes of TPBCs was shown as follows. The three genes that exhibited the highest accuracy in identifying TPBCs of luminal A subtype were STC2, BCL2 (highly expressed in luminal A subtype) and MKI67 (lowly expressed in luminal A subtype). In cohort 4, we defined a group of luminal A-like TPBCs as TPBCs with low expression of MKI67 as well as high expression of STC2 and/or BCL2. Compared with patients with non-luminal A-like TPBC (n = 110), those with luminal A-like TPBC (n = 55) had better disease-free survival (DFS) in both univariate (Log-rank P = 0.029) and multivariate analyses (hazard ratio = 0.25, P = 0.025). In the group with non-luminal A-like TPBCs, patients treated with trastuzumab (n = 67) showed better DFS than those not treated with it (n = 43) (Log-rank P = 0.019), while in the group with luminal A-like TPBCs, there is no difference in DFS between patients treated with trastuzumab (n = 22) and those not treated with it (n = 33) (Log-rank P = 0.993).

PAM50 intrinsic subtypes of TPBCsPAM50 intrinsic subtypeCohort 1Cohort 2Cohort 3 N (%)N (%)N (%)Luminal A43 (52.4)15 (40.5)13 (43.3)Luminal B28 (34.1)17 (45.9)12 (40.0)HER2-enriched9 (11.0)2 (5.4)3 (10.0)Normal-like1 (1.2)2 (5.4)1 (3.3)Basal-like1 (1.2)1 (2.7)1 (3.3)

Conclusions TPBCs are heterogeneous in terms of intrinsic molecular subtype. Evaluating the expression of STC2, BCL2 and MKI67 by IHC staining can help us to conveniently identify a group of luminal A-like TPBCs. Patients with this group of TPBCs have relatively good prognosis and may only gain limited benefit from adjuvant trastuzumab.

Citation Format: Zhao S, Jin X, Jiang Y-Z, Shao Z-M. Identification of luminal A-like subgroup among ER+/PR+/HER2+ breast cancers and its clinical implications [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 P3-07-12.

Phosphoproteome profiling revealed abnormally phosphorylated AMPK and ATF2 involved in glucose metabolism and tumorigenesis of GH-PAs

PURPOSE

Protein phosphorylation plays a key role in tumorigenesis and progression. However, little is known about the phosphoproteome profiles of growth hormone-secreting pituitary adenomas (GH-PAs). The aim of this study was to identify critical biomarkers and signaling pathways that might play important roles in GH-PAs and may, therefore, represent potential therapeutic targets.

METHODS

The differential phosphoprotein expression patterns involved in GH-PAs were investigated by nano-LC-MS/MS in a group of samples. The phosphoprotein expression data were analyzed by bioinformatics. The expression levels of the candidate phosphorylated AMPK (ser496) and ATF2 (ser112) were validated by Western blot analysis in another group of samples.

RESULTS

A total of 1213 phosphorylated protein sites corresponding to 667 proteins were significantly different between GH-PAs and healthy pituitary glands. Among these phosphorylated sites, 871 exhibited lower levels of phosphorylation in GH-PAs. Moreover, 140 novel phosphosites corresponding to 93 proteins were differentially phosphorylated between GH-PAs and healthy pituitary glands, 101 of which showed decreased phosphorylation in GH-PAs. The majority of differentially expressed phosphorylated proteins were significantly enriched in glycolysis and the AMPK signaling pathway in GH-PAs. The AMPK signaling pathway was demonstrated to be inhibited in GH-PAs by pathway activity analysis (z score = - 2.324). Notably, the phosphorylated levels of AMPK (ser496) and ATF2 (ser112) were significantly lower in GH-PAs than in healthy pituitary glands.

CONCLUSION

These findings suggest that decreased phosphorylation of the AMPK/ATF2 pathway may be critical for glucose metabolism and tumorigenesis in GH-PAs.

Berberine promotes glucose uptake and inhibits gluconeogenesis by inhibiting deacetylase SIRT3

OBJECTIVE

Many studies have confirmed the glucose-lowering effect of berberine in type 2 diabetes patients. Although the mechanism of action of berberine involves the improvement of insulin sensitivity, its hypoglycemic mechanism remains elusive. Here we show a new mechanism by which berberine antagonizes glucagon signaling and find that SIRT3 is involved in the hypoglycemic effect of berberine.

METHODS

Gene knockout and overexpression were used to assess the inhibitory effect of berberine on SIRT3. Downstream signaling pathways and the hypoglycemic effect of SIRT3 were evaluated by immunoblotting and metabolic monitoring.

RESULTS

We found that berberine led to mitochondrial dysfunction and AMP accumulation by inhibiting deacetylase SIRT3. We confirmed that AMP accumulation activated the AMPK signaling pathway and further promoted glucose uptake. Simultaneously, AMP accumulation reduced cyclic AMP (cAMP) levels and abrogated the phosphorylation of critical protein targets of protein kinase A (PKA). Furthermore, we found that phosphoenolpyruvate carboxykinase 1 (PEPCK1) is a key gluconeogenesis enzyme that can be stabilized by glucagon. Berberine caused significant PEPCK1 ubiquitination and degradation by antagonizing glucagon and was accompanied by high levels of PEPCK1 acetylation. Interestingly, berberine-induced glucagon inhibition is independent of AMPK activation. The in vivo data from sirt3 knockout mice were further confirmed by the in vitro experiments.

CONCLUSIONS

Berberine promotes glucose uptake and inhibits gluconeogenesis by inhibiting SIRT3, and regulating mitochondria-related pathways may provide a novel approach to the development of antidiabetic drugs.

Molecular characterization, expression pattern and metabolic activity of flavin-dependent monooxygenases in Spodoptera exigua

Enhanced detoxification is one of the important mechanisms for insecticide resistance. Most research in this field to date has focused on the role of cytochrome P450s. Our previous work revealed that flavin-dependent monooxygenases (FMOs) were involved in metabolic resistance of Spodoptera exigua. In the present study we investigated the molecular characteristics, expression patterns and oxidative activities of SeFMO on insecticides. Three FMO genes, which encode proteins with the typical FMO motifs, were cloned from S. exigua. The oxidative activities of eukaryotically expressed SeFMO enzymes were verified with the model substrate of FMO. Importantly, the SeFMOs had significantly higher oxidative activities on metaflumizone and lambda-cyhalothrin than on model substrates and other insecticides tested. The three SeFMOs were mainly expressed in the midgut, fat body and Malpighian tubules. The tissues responsible for xenobiotic metabolism and their expression characteristics were similar to those of P450s acting as detoxification genes. The study also revealed that the expression of SeFMOs could be induced by insecticide exposure, and that SeFMOs were over-expressed in a metaflumizone-resistant strain of S. exigua. These results suggest that SeFMOs are important insecticide detoxifying enzymes, and that over-expression of FMO genes may be one of the mechanisms for metabolic resistance in S. exigua.

Standardizing compression testing for measuring the stiffness of human bone

Objectives

The ability to determine human bone stiffness is of clinical relevance in many fields, including bone quality assessment and orthopaedic prosthesis design. Stiffness can be measured using compression testing, an experimental technique commonly used to test bone specimens in vitro. This systematic review aims to determine how best to perform compression testing of human bone.

Methods

A keyword search of all English language articles up until December 2017 of compression testing of bone was undertaken in Medline, Embase, PubMed, and Scopus databases. Studies using bulk tissue, animal tissue, whole bone, or testing techniques other than compression testing were excluded.

Results

A total of 4712 abstracts were retrieved, with 177 papers included in the analysis; 20 studies directly analyzed the compression testing technique to improve the accuracy of testing. Several influencing factors should be considered when testing bone samples in compression. These include the method of data analysis, specimen storage, specimen preparation, testing configuration, and loading protocol.

Conclusion

Compression testing is a widely used technique for measuring the stiffness of bone but there is a great deal of inter-study variation in experimental techniques across the literature. Based on best evidence from the literature, suggestions for bone compression testing are made in this review, although further studies are needed to establish standardized bone testing techniques in order to increase the comparability and reliability of bone stiffness studies.

Cite this article: S. Zhao, M. Arnold, S. Ma, R. L. Abel, J. P. Cobb, U. Hansen, O. Boughton. Standardizing compression testing for measuring the stiffness of human bone. Bone Joint Res 2018;7:524–538. DOI: 10.1302/2046-3758.78.BJR-2018-0025.R1.

Analysis of evolution and genetic diversity of sweetpotato and its related different polyploidy wild species I. trifida using RAD-seq

BACKGROUND

Sweetpotato (Ipomoea batatas (L.) Lam.) is one of the most important crops from the family of Convolvulaceae. It is widely reported that cultivated sweetpotato was originated from Ipomoea trifida. However, diploid, tetraploid and hexaploid I. trifida were found in nature. The relationship, between them, and among them and sweetpotato, is remaining unclear.

RESULTS

In the present study, we detected the genome diversity and relationship of sweetpotato and different polyploidy types I. trifida using Restriction-site Associated DNA Sequencing (RAD-seq). A total of 38,605 RAD-tags containing 832,204 SNPs had been identified. These tags were annotated using five public databases, about 11,519 tags were aligned to functional genes in various pathways. Based on SNP genotype, phylogenetic relation analysis results confirmed that cultivated sweetpotato has a closer relationship with I. trifida 6× than with I. trifida 4X and I. trifida 2×. Besides, 5042 SSRs were detected in I. trifida 6×, and 3202 pairs of high-quality SSR primers were developed. A total of 68 primers were randomly selected and synthesized, of which 61 were successfully amplified.

CONCLUSION

These results provided new evidence that cultivated sweetpotato originated from I. trifida 6×, and that I. trifida 6× evolved from I. trifida 4X and I. trifida 2×. Therefore, using I. trifida 6× as the model plant of sweetpotato research should be more practical than using I. trifida 2× in the future. Meanwhile, sequence information and markers from the present study will be helpful for sweetpotato and I. trifida studies in the future.

Molecular characterization of Babesia microti seroreactive antigen 5-1-1 and development of rapid detection methods for anti-B. microti antibodies in serum

Babesiosis has become a new global threat impacting human health, and most human babesiosis cases are caused by Babesia microti. Until now few antigens of B. microti have been described which can be used for the diagnosis of human babesiosis. In the present study, we report on the bioinformatic analysis, cloning and expression of the sequence encoding the B. microti seroreactive antigen 5-1-1 to investigate its potential incorporation in serologic diagnostic tools for babesiosis. Bioinformatic analysis and recombinant gene expression were performed to molecularly characterize seroreactive antigen 5-1-1. Enhanced chemiluminescence (ECL)-Western blot methods were used to detect specific antibodies in infected mice. Immunofluorescence antibody assays (IFA) were performed to detect the localization of BmSA5-1-1 in B. microti parasites. ELISA and immunochromatographic (ICT) tests were developed using recombinant BmSA5-1-1 to evaluate its potential use in rapid detection methods for B. microti antibodies and for the diagnosis of babesiosis. A recombinant expression plasmid was constructed by inserting the target gene fragment in the pET28a vector after double digestion with BamHI and XhoI restriction enzymes. The recombinant BmSA5-1-1 protein was expressed in Escherichia coli (rBmSA5-1-1) and purified by means of Ni-nitrilotriacetic acid (NTA) agarose columns. Polyclonal antibodies were generated against rBmSA5-1-1. Based on indirect immunofluorescence assay results, BmSA5-1-1 appeared to localize on the surface of B. microti. ELISA tests using the rBmSA5-1-1 antigen detected specific antibodies from infected mice as early as 4 days post-infection. Our results indicate that the two methods we developed can detect specific antibodies in mice at different stages of infection with sensitivities of 100% (rBmSA5-1-1 ELISA) and 90% (ICT). The specificity of the two methods was 100%. Sera of patients suffering from other closely related parasitic diseases, such as malaria and toxoplasmosis, produced negative results. In conclusion, seroreactive antigen 5-1-1, a member of the BMN1 protein family, is expressed on the outer surface of B. microti and is a promising candidate antigen for the early diagnosis of babesiosis. rBmSA5-1-1 ELISA and ICT methods show good potential for detecting specific antibodies in mice at different stages of infection.