mTOR-dependent loss of PON1 secretion and antiphospholipid autoantibody production underlie autoimmunity-mediated cirrhosis in transaldolase deficiency

Transaldolase deficiency predisposes to chronic liver disease progressing from cirrhosis to hepatocellular carcinoma (HCC). Transition from cirrhosis to hepatocarcinogenesis depends on mitochondrial oxidative stress, as controlled by cytosolic aldose metabolism through the pentose phosphate pathway (PPP). Progression to HCC is critically dependent on NADPH depletion and polyol buildup by aldose reductase (AR), while this enzyme protects from carbon trapping in the PPP and growth restriction in TAL deficiency. Although AR inactivation blocked susceptibility to hepatocarcinogenesis, it enhanced growth restriction, carbon trapping in the non-oxidative branch of the PPP and failed to reverse the depletion of glucose 6-phosphate (G6P) and liver cirrhosis. Here, we show that inactivation of the TAL-AR axis results in metabolic stress characterized by reduced mitophagy, enhanced overall autophagy, activation of the mechanistic target of rapamycin (mTOR), diminished glycosylation and secretion of paraoxonase 1 (PON1), production of antiphospholipid autoantibodies (aPL), loss of CD161+ NK cells, and expansion of CD38+ Ito cells, which are responsive to treatment with rapamycin in vivo. The present study thus identifies glycosylation and secretion of PON1 and aPL production as mTOR-dependent regulatory checkpoints of autoimmunity underlying liver cirrhosis in TAL deficiency.

Upregulated circ_0002141 facilitates oral squamous cell carcinoma progression via the miR-1231/EGFR axis

OBJECTIVES

The dysregulation of circular RNAs (circRNAs) is implicated in the progression of various cancers. This study was aimed at expounding the role and mechanism of hsa_circ_0002141 in the OSCC progression.

MATERIALS AND METHODS

Circ_0002141 expression was examined in 52 pairs of OSCC tissues and matched adjacent tissue samples by quantitative real-time polymerase chain reaction (qRT-PCR) assay. After circ_0002141 was overexpressed or knocked down in OSCC cell lines, cell counting kit-8 (CCK-8) assay, Transwell assay, flow cytometry, and Western blotting were conducted to detect the changes in the growth, migration, invasion and apoptosis of OSCC cells. Western blot assay, qRT-PCR and dual-luciferase reporter assay were performed to clarify the interplay among circ_0002141, miR-1231, and epidermal growth factor receptor (EGFR).

RESULTS

Circ_0002141 expression was significantly upregulated in OSCC tissues and cell lines. Circ_0002141 overexpression markedly promoted the proliferation, migration, and invasion of OSCC cells whereas reduced the apoptotic of OSCC cells. Also, circ_0002141 knockdown suppressed the malignant characteristics of OSCC cells. EGFR was validated as the target of miR-1231. Besides, circ_0002141 could sponge miR-1231 and upregulate EGFR expression in OSCC cells.

CONCLUSION

Circ_0002141/miR-1231/EGFR axis is involved in the progression of OSCC.

microRNA-17 is a tumor suppressor in oral squamous cell carcinoma and is repressed by LSD1

OBJECTIVE

The effects of epigenetic modifiers have been uncovered on cellular reprogramming and, specifically, on sustaining characteristics of cancer stem cells. We here aim to investigate whether lysine-specific demethylase 1 (LSD1) affects the development of oral squamous cell carcinoma (OSCC) by sustaining the cancer stem cells from OSCC (OSCSCs).

METHODS

RT-qPCR detection was firstly conducted to screen out research gene by determining differential expression of histone demethylases and methylases in identified OSCSCs. Then, microarray analysis was carried out in cells with poor expression of LSD1.

RESULTS

OSCSCs expressed high levels of LSD1, and LSD1 inhibition reduced cell viability, migration, invasion, and sphere formation of OSCSCs. Later mechanistic studies suggested that LSD1 inhibited microRNA (miR)-17 expression through histone demethylation. miR-17 bound to KPNA2, and LSD1 downstream genes were mainly enriched in the PI3K/AKT pathway. Importantly, miR-17 inhibitor reversed the inhibitory effect of si-LSD1 on cell activity, while si-KPNA2 abolished the promotive effect of miR-17 inhibitor on cell activity both in vitro and in vivo.

CONCLUSION

Overall, LSD1 functions as a cancer stem cell supporter in OSCC by catalyzing demethylation of miR-17 and activating the downstream KPNA2/PI3K/AKT pathway, which contributes to understanding of the mechanisms associated with epigenetic regulation in OSCC.

Identification of Two Isoforms of Canine Tetherin in Domestic Dogs and Characterization of Their Antiviral Activity against Canine Influenza Virus

Canine influenza virus (CIV) significantly threatens the canine population and public health. Tetherin, an innate immune factor, plays an important role in the defense against pathogen invasion and has been discovered to restrict the release of various enveloped viruses. Two isoforms of canine tetherin (tetherin-X1 and tetherin-X2) were identified in peripheral blood leukocytes of mixed-breed dogs using reverse transcription polymerase chain reaction (RT-PCR). Amino acid alignment revealed that relative to full-length tetherin (tetherin-X1) and truncated canine tetherin (tetherin-X2) exhibited deletion of 34 amino acids. The deletion occurred at the C-terminus of the coiled-coiled ectodomain and the N-terminus of the glycosylphosphatidylinositol (GPI)-anchor domain. Tetherin-X2 was localized subcellularly at the cell membrane, which was consistent with the localization of tetherin-X1. In addition, canine tetherin-X1 and tetherin-X2 restricted the release of H3N2 CIV. However, canine tetherin-X1 had higher antiviral activity than canine tetherin-X2, indicating that the C-terminus of the coiled-coiled ectodomain and the N-terminus of the GPI-anchor domain of canine tetherin (containing the amino acids deleted in tetherin-X2) are critical for its ability to restrict H3N2 CIV release. This study provides insights for understanding the key functional domains of tetherin that restrict CIV release.

Swine Interferon-Inducible Transmembrane Proteins Potently Inhibit African Swine Fever Virus Replication

African swine fever virus (ASFV) causes an acute, hemorrhagic, and highly contagious disease in domestic swine, leading to significant economic losses to the global porcine industry. Restriction factors of innate immunity play a critical in host antiviral action. However, function of swine restriction factors of innate immunity on ASFV has been seldomly investigated. In this study, we determined five homologues of swine interferon-induced transmembrane proteins (SwIFITM [named SwIFITM1a, -1b, -2, -3, and -5]), and we found that they all exhibit potent antiviral activity against ASFV. Expression profile analysis indicated that these SwIFITMs are constitutively expressed in most porcine tissues. Whether infected with ASFV or treated with swine interferon, the expression levels of SwIFITMs were induced in vitro. The subcellular localization of SwIFITMs was similar to that of their human homologues. SwIFITM1a and -1b localized to the plasma membrane, SwIFITM2 and -3 focused on the cytoplasm and the perinuclear region, while SwIFITM5 accumulated in the cell surface and cytoplasm. The overexpression of SwIFITM1a, -1b, -2, -3, or -5 could significantly inhibit ASFV replication in Vero cells, whereas knockdown of these genes could enhance ASFV replication in PAMs. We blocked the constitutive expression of endogenous IFITMs in Vero cells using a CRISPR-Cas9 system and then infected them with ASFV. The results indicated that the knockout of endogenous IFITMs could enhance ASFV replication. Finally, we expressed five SwIFITMs in knockout Vero cell lines and then challenged them with ASFV. The results showed that all of the SwIFITMs had a strong antiviral effect on ASFV. This research will further expand the understanding of the anti-ASFV activity of porcine IFITMs.

Canine Interferon-Inducible Transmembrane Protein Is a Host Restriction Factor That Potently Inhibits Replication of Emerging Canine Influenza Virus

Canine influenza virus (CIV) is an emerging virus that is associated with major hidden hazards to the canine population and public health. Until now, how canine uses its innate immunity to restrict CIV replication is seldomly investigated. Recently, studies on interferon-inducible transmembrane (IFITM) of several major hosts of influenza virus (human, chicken, duck, pig) indicated it can potently restrict the viral replication. Here, the gene locus of five previously annotated canine IFITM (caIFITM) genes was determined on chromosome 18 using multiple bioinformatics strategies, provisionally designated as caIFITM1, caIFITM2a, caIFITM2b, caIFITM3, and caIFITM5. An analysis on protein sequences between caIFITM and its homologs indicated they shared the same conserved amino acids important for the antiviral activity. Expression profile analysis showed that caIFITM was constitutively expressed in tissues and MDCK cell line. After treatment with interferon or infection with influenza virus, the expression level of caIFITM increased with different degrees in vitro. An animal challenge study demonstrated CIV infection resulted in upregulation of caIFITM in beagles. caIFITMs had a similar subcellular localization to their human homologs. caIFITM1 was present at the cell surface and caIFITM3 was present perinuclearly and colocalized with LAMP1-containing compartments. Finally, we generated A549 cell lines stably expressing caIFITM and challenged them with influenza virus. The result demonstrated caIFITM1, caIFITM2a, caIFITM2b, and caIFITM3 had a potent antiviral activity against influenza virus. Our study will help better understand the evolutional pattern of IFITM and its role in the host’s defense against virus infection.

First identification and genomic characterization of equine hepacivirus subtype 2 in China

Equine hepacivirus (EqHV) is a newly discovered hepatitis C virus-like virus that can infect equines. EqHV strains circulating worldwide have been classified into subtypes 1-3. In previous studies, we detected the presence of EqHV strains of subtype 1 and 3 in China. To determine whether EqHV strains of subtype 2 are prevalent in China, serum samples were collected from 133 racehorses in Guangdong province in 2021 and were tested for EqHV RNA by RT-PCR, and the positive rate was 9% (12/133). Sequencing of the NS3 gene revealed that one field strain (GD2021) had a high degree of genetic similarity to EqHV strains of subtype 2. Subsequent genome sequencing and analysis demonstrated that strain GD2021 belongs to subtype 2. The present study enriches our knowledge about the genetic diversity of EqHV in China.

Analysis of mutation status and homologous recombination deficiency in tumors of patients with germline BRCA1 or BRCA2 mutations and metastatic breast cancer: OlympiAD

BACKGROUND

Presence of a germline BRCA1 and/or BRCA2 mutation (gBRCAm) may sensitize tumors to poly(ADP-ribose) polymerase (PARP) inhibition via inactivation of the second allele, resulting in gene-specific loss of heterozygosity (gsLOH) and homologous recombination deficiency (HRD). Here we explore whether tissue sample testing provides an additional route to germline testing to inform treatment selection for PARP inhibition.

PATIENTS AND METHODS

In this prespecified exploratory analysis, BRCA1 and/or BRCA2 mutations in blood samples (gBRCAm) and tumor tissue (tBRCAm) were analyzed from patients with human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer and known gBRCAm, enrolled in the phase III OlympiAD trial. The frequency and nature of tBRCAm, HRD score status [HRD-positive (score ≥42) versus HRD-negative (score <42) using the Myriad myChoice® CDx test] and rates of gsLOH were determined, and their impact on clinical efficacy (objective response rate and progression-free survival) was explored.

RESULTS

Tissue samples from 161/302 patients yielded tBRCAm, HRD and gsLOH data for 143 (47%), 129 (43%) and 125 (41%) patients, respectively. Concordance between gBRCAm and tBRCAm was 99%. gsLOH was observed in 118/125 (94%) patients [BRCA1m, 73/76 (96%); BRCA2m, 45/49 (92%)]. A second mutation event was recorded for two of the three BRCA1m patients without gsLOH. The incidence of HRD-negative was 16% (21/129) and was more common for BRCA2m (versus BRCA1m) and/or for hormone receptor-positive (versus triple-negative) disease. Olaparib antitumor activity was observed irrespective of HRD score.

CONCLUSIONS

gBRCAm identified in patients with HER2-negative metastatic breast cancer by germline testing in blood was also identified by tumor tissue testing. gsLOH was common, indicating a high rate of biallelic inactivation in metastatic breast cancer. Olaparib activity was seen regardless of gsLOH status or HRD score. Thus, additional tumor testing to inform PARP inhibitor treatment selection may not be supported for these patients.

Novel parvovirus in cats, China

Parvovirus is a common element of the feline virus group and usually causes gastroenteritis and leukopenia in cats. In this study, we identified a novel protoparvovirus from the Chinese domestic cats, which is genetically similar to canine bufavirus (98.0%-99.8%), but sharing low amino acid identities in the viral structural proteins 2 (VP2) (36.1-37.2%) to the well-known canine parvovirus type 2 and feline panleukopenia virus. This virus was provisionally designated as feline bufavirus (FBuV). Screening of fecal samples revealed a prevalence of 7.4% (19/257) in domestic cats. Diarrhea was present in 52.6% (10/19) of cats positive for FBuV. However, statistical analysis showed no association between FBuV and clinical signs. VP2 gene of the 19 field FBuV was sequenced and phylogenetic analysis demonstrated that FBuV determined from China had a genetic diversity. This study will strengthen the understanding of the epidemiology and genetic diversity of bufavirus and provide a foundation for further studies.

Tongxin formula protects H9c2 cardiomyocytes from cobalt chloride-induced hypoxic injury via inhibition of apoptosis

In this study, the effect of the Tongxin formula (TXF) on the apoptosis of H9c2 cardiomyocytes induced by cobalt chloride (CoCl₂) was investigated, and the potential mechanism was explored. A hypoxic injury model of H9c2 cardiomyocytes was established using CoCl₂. The cell viability was measured using a Cell Counting Kit-8 assay. The lactate dehydrogenase (LDH) release and caspase-3 activity were measured using spectrophotometry. The apoptosis was measured via Annexin V-FITC/PI staining and flow cytometry. The changes in the mitochondrial membrane potential were examined using immunofluorescence microscopy following the loading of JC-1 probes. The expressions of apoptosis-related proteins and key proteins in the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathway were examined via immunoblotting. The different TXF concentrations studied significantly improved the percentage of viability of cardiomyocytes with hypoxic injury, and the LDH release, apoptotic rate, caspase-3 activity, and levels of cleaved caspase-3 protein were reduced in the injured cells. Additionally, the TXF group had increased mitochondrial membrane potential, upregulated expression of Bcl-2 and p-Akt proteins, and significantly reduced expression of cleaved caspase-3 protein in the cells with hypoxic injury. Moreover, in the TXF group, the treatment significantly reduced the BAX protein expression, but the difference was not statistically significant compared with the CoCl2 group. In this study, TXF regulated the expression of apoptosis-related proteins, inhibited apoptosis, increased the mitochondrial membrane potential, and alleviated damage to the mitochondrial membrane, thereby protecting the cardiomyocytes from hypoxic injury. The underlying mechanism could be related to activation of the PI3K/Akt signaling pathway and upregulation of the Bcl-2 protein.

MiR-143-3p Inhibits Osteogenic Differentiation of Human Periodontal Ligament Cells by Targeting KLF5 and Inactivating the Wnt/β-Catenin Pathway

Human periodontal ligament cells (hPDLCs) play a vital role in cell regeneration and tissue repair with multi-directional differentiation potential. microRNAs (miRs) are implicated in the osteogenesis of hPDLCs. This study explored the mechanism of miR-143-3p in osteogenesis of hPDLCs. Osteogenic differentiation of isolated hPDLCs was induced. KLF5 expression during osteogenic differentiation of hPDLCs was detected and then silenced in hPDLCs. Binding relationship between KLF5 and miR-143-3p was predicted and verified. hPDLCs were treated with miR-143-3p mimic or overexpressing KLF5, and then osteogenic specific markers and mineralized nodules were measured. The key factors of the Wnt/β-catenin pathway during osteogenesis of hPDLCs were measured. KLF5 expression was upregulated during osteogenesis of hPDLCs. KLF5 silencing or miR-143-3p mimic reduced osteogenic specific markers and mineralized nodules. Overexpression of KLF5 could reverse the inhibitory effect of miR-143-3p on osteogenic differentiation. miR-143-3p mimic and KLF5 silencing inactivated the Wnt/β-catenin pathway. Activation of the Wnt/β-catenin pathway reversed the repression effect of miR-143-3p mimic on osteogenesis of hPDLCs. In conclusion, miR-143-3p inhibited osteogenic differentiation of hPDLCs by targeting KLF5 and inactivating the Wnt/β-catenin pathway.

Androgen deprivation-induced elevated nuclear SIRT1 promotes prostate tumor cell survival by reactivation of AR signaling

The NAD⁺-dependent deacetylase, Sirtuin 1 (SIRT1) is involved in prostate cancer pathogenesis. However, the actual contribution is unclear as some reports propose a protective role while others suggest it is harmful. We provide evidence for a contextual role for SIRT1 in prostate cancer. Our data show that (i) mice orthotopically implanted with SIRT1-silenced LNCaP cells produced smaller tumors; (ii) SIRT1 suppression mimicked AR inhibitory effects in hormone responsive LNCaP cells; and (iii) caused significant reduction in gene signatures associated with E2F and MYC targets in AR-null PC-3 and E2F and mTORC1 signaling in castrate-resistant ARv7 positive 22Rv1 cells. Our findings further show increased nuclear SIRT1 (nSIRT1) protein under androgen-depleted relative to androgen-replete conditions in prostate cancer cell lines. Silencing SIRT1 resulted in decreased recruitment of AR to PSA enhancer selectively under androgen-deprivation conditions. Prostate cancer outcome data show that patients with higher levels of nSIRT1 progress to advanced disease relative to patients with low nSIRT1 levels. Collectively, we demonstrate that lowering SIRT1 levels potentially provides new avenues to effectively prevent prostate cancer recurrence.

Technical validation of a new microfluidic device for enrichment of CTCs from large volumes of blood by using buffy coats to mimic diagnostic leukapheresis products

Diagnostic leukapheresis (DLA) enables to sample larger blood volumes and increases the detection of circulating tumor cells (CTC) significantly. Nevertheless, the high excess of white blood cells (WBC) of DLA products remains a major challenge for further downstream CTC enrichment and detection. To address this problem, we tested the performance of two label-free CTC technologies for processing DLA products. For the testing purposes, we established ficollized buffy coats (BC) with a WBC composition similar to patient-derived DLA products. The mimicking-DLA samples (with up to 400 × 106 WBCs) were spiked with three different tumor cell lines and processed with two versions of a spiral microfluidic chip for label-free CTC enrichment: the commercially available ClearCell FR1 biochip and a customized DLA biochip based on a similar enrichment principle, but designed for higher throughput of cells. While the samples processed with FR1 chip displayed with increasing cell load significantly higher WBC backgrounds and decreasing cell recovery, the recovery rates of the customized DLA chip were stable, even if challenged with up to 400 × 106 WBCs (corresponding to around 120 mL peripheral blood or 10% of a DLA product). These results indicate that the further up-scalable DLA biochip has potential to process complete DLA products from 2.5 L of peripheral blood in an affordable way to enable high-volume CTC-based liquid biopsies.

LncRNA MAFG-AS1 regulates human periodontal ligament stem cell proliferation and Toll-like receptor 4 expression

LncRNA MAFG-AS1 is predicted to interact with miR-146a, which can target Toll-like receptor 4 (TLR4), a key player in periodontitis. This study aimed to investigate the roles of MAFG-AS1 in periodontitis. It was observed that MAFG-AS1 was downregulated in the human periodontal ligament stem cells (PDLSCs) derived from periodontitis-affected teeth. Dual-luciferase assay revealed that co-transfection of MAFG-AS1 expression vector and miR-146a mimic showed significantly lower relative luciferase activity comparing to co-transfection of MAFG-AS1 expression vector and negative control (NC) miRNA. However, MAFG-AS1 and miR-146a failed to affect each other. Interestingly, MAFG-AS1 overexpression led to the upregulated TLR4. In addition, MAFG-AS1 overexpression also led to the inhibited proliferation of PDLSCs. Therefore, MAFG-AS1 may regulate the proliferation of PDLSCs and the expression of TLR4 to participate in periodontitis.

Circular RNA ITCH Suppresses Cell Proliferation but Induces Apoptosis in Oral Squamous Cell Carcinoma by Regulating miR-421/PDCD4 Axis

Background

Circular RNAs (circRNAs), a group of covalently closed non-coding RNAs, serve critical regulatory roles in many human cancers, including oral squamous cell carcinoma (OSCC). The purpose of this study was to investigate the functional role of circular RNA ITCH (circ-ITCH) in OSCC and the underlying mechanisms.

Methods

RT-qPCR analysis was applied to detect the expression levels of circ-ITCH in OSCC tissues and cell lines. MTT assay and flow cytometer analysis were used to evaluate the effects of circ-ITCH overexpression on the proliferation and apoptosis of OSCC cells. Bioinformatics analysis and dual-luciferase reporter assay were applied to determine the binding relation between circ-ITCH and miR-421 as well as PDCD4 mRNA and miR-421.

Results

Our results showed that circ-ITCH expression was remarkably decreased in OSCC tissues and cell lines. Low circ-ITCH expression was strongly associated with adverse clinicopathological characteristics of OSCC patients. Moreover, functional assays demonstrated that circ-ITCH overexpression significantly inhibited OSCC cell proliferation and induced cell apoptosis. Our data further uncovered that circ-ITCH could bind directly to miR-421 and block its repression on PDCD4 in OSCC. MiR-421 expression was significantly increased in OSCC tissues and was inversely correlated with circ-ITCH expression. Notably, miR-421 restoration blocked the tumor-suppressive role of circ-ITCH in OSCC cells.

Conclusion

In conclusion, our study reveals that circ-ITCH serves as a tumor suppressor in OSCC partly by regulating miR-421/PDCD4 axis.

Single-site laparoscopic percutaneous extraperitoneal closure (SLPEC) of hernia sac high ligation using an ordinary taper needle: a novel technique for pediatric inguinal hernia

PURPOSE

Laparoscopic high ligation of the internal inguinal ring is an alternative procedure for treatment of pediatric inguinal hernia (PIH), with a major trend toward increasing use of extracorporeal knotting and decreasing use of working ports. We have utilized this laparoscopic technique to treat the entire spectrum of PIH (including incarcerated cases) for more than 17 years, and the technique continues to evolve and improve. We herein report our latest modification of this minimally invasive technique, namely single-site laparoscopic percutaneous extraperitoneal closure (SLPEC) of hernia sac high ligation using an ordinary taper needle, and evaluate its safety and efficacy.

METHODS

From July 2016 to July 2019, 790 children with indirect PIH were treated by laparoscopic surgery. All patients underwent high ligation surgery with a modified single-site laparoscopic technique mainly performed by extracorporeal suturing with an ordinary closed-eye taper needle (1/2 arc 11 × 34). The clinical data were retrospectively analyzed.

RESULTS

All surgeries were successful without serious complications. A contralateral patent processus vaginalis (CPPV) was found intraoperatively and subsequently repaired in 190 patients (25.4%). The mean operative time was 15 min (8-25 min) for 557 unilateral hernias and 21 min (14-36 min) for 233 bilateral hernias. The mean postoperative stay was 20 h. Minor complications occurred in five patients (0.63%) and were managed properly, with no major impact on the final outcomes. No recurrence was noted in the patients who were followed up for 6-42 months. No obvious scar was present postoperatively.

CONCLUSION

Modified SLPEC of hernia sac high ligation using an ordinary taper needle for repair of indirect PIH is a safe, reliable, and minimally invasive procedure with satisfactory outcome, with no special device being needed. It is easy to learn and perform and is worthy of popularization in the clinical setting.

RAD51 foci as a functional biomarker of homologous recombination repair and PARP inhibitor resistance in germline BRCA-mutated breast cancer

Background

BRCA1 and BRCA2 (BRCA1/2)-deficient tumors display impaired homologous recombination repair (HRR) and enhanced sensitivity to DNA damaging agents or to poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi). Their efficacy in germline BRCA1/2 (gBRCA1/2)-mutated metastatic breast cancers has been recently confirmed in clinical trials. Numerous mechanisms of PARPi resistance have been described, whose clinical relevance in gBRCA-mutated breast cancer is unknown. This highlights the need to identify functional biomarkers to better predict PARPi sensitivity.

Patients and methods

We investigated the in vivo mechanisms of PARPi resistance in gBRCA1 patient-derived tumor xenografts (PDXs) exhibiting differential response to PARPi. Analysis included exome sequencing and immunostaining of DNA damage response proteins to functionally evaluate HRR. Findings were validated in a retrospective sample set from gBRCA1/2-cancer patients treated with PARPi.

Results

RAD51 nuclear foci, a surrogate marker of HRR functionality, were the only common feature in PDX and patient samples with primary or acquired PARPi resistance. Consistently, low RAD51 was associated with objective response to PARPi. Evaluation of the RAD51 biomarker in untreated tumors was feasible due to endogenous DNA damage. In PARPi-resistant gBRCA1 PDXs, genetic analysis found no in-frame secondary mutations, but BRCA1 hypomorphic proteins in 60% of the models, TP53BP1-loss in 20% and RAD51-amplification in one sample, none mutually exclusive. Conversely, one of three PARPi-resistant gBRCA2 tumors displayed BRCA2 restoration by exome sequencing. In PDXs, PARPi resistance could be reverted upon combination of a PARPi with an ataxia-telangiectasia mutated (ATM) inhibitor.

Conclusion

Detection of RAD51 foci in gBRCA tumors correlates with PARPi resistance regardless of the underlying mechanism restoring HRR function. This is a promising biomarker to be used in the clinic to better select patients for PARPi therapy. Our study also supports the clinical development of PARPi combinations such as those with ATM inhibitors.

Thyroid abnormalities following the use of cytotoxic T-lymphocyte antigen-4 and programmed death receptor protein-1 inhibitors in the treatment of melanoma

CONTEXT

Checkpoint inhibitors are emerging as important cancer therapies but are associated with a high rate of immune side effects, including endocrinopathy.

OBJECTIVE

To determine the burden of thyroid dysfunction in patients with melanoma treated with immune checkpoint inhibitors and describe the clinical course.

DESIGN AND PATIENTS

Consecutive patients with melanoma treated with either ipilimumab, nivolumab, pembrolizumab or the combination of ipilimumab and nivolumab were identified. Baseline thyroid function tests were used to exclude those with pre-existing thyroid abnormalities, and thyroid function tests during treatment used to identify those with thyroid dysfunction.

RESULTS

Rates of overt thyroid dysfunction were in keeping with the published phase 3 trials. Hypothyroidism occurred in 13·0% treated with a programmed death receptor-1 (PD-1) inhibitor and 22·2% with a combination of PD-1 inhibitor and ipilimumab. Transient subclinical hyperthyroidism was observed in 13·0% treated with a PD-1 inhibitor, 15·9% following a PD-1 inhibitor, and 22·2% following combination treatment with investigations suggesting a thyroiditic mechanism rather than Graves' disease, and a high frequency of subsequent hypothyroidism. Any thyroid abnormality occurred in 23·0% following ipilimumab, 39·1% following a PD-1 inhibitor and 50% following combination treatment. Abnormal thyroid function was more common in female patients.

CONCLUSION

Thyroid dysfunction occurs commonly in patients with melanoma treated with immune checkpoint inhibitors, with rates, including subclinical dysfunction, occurring in up to 50%.

Validation of daily increment deposition and early growth of mud carp Cirrhinus molitorella

In this study, laboratory reared Cirrhinus molitorella from hatching through to the juvenile stage were used to validate daily increment deposition. Lapilli were suitable for ageing C. molitorella. The slope of the linear relationships between increment counts and age was not significantly different from 1 (n = 258, P > 0·05), indicating that growth increments are deposited daily. The first increment following the first-feeding check formed 3 days post hatch (dph). One hundred and twenty-three juveniles, ranging from 36·4 to 84·7 mm in body length (L_B ), were collected in the Pear River estuary from July to January in both 2014 and 2015 and used to estimate growth rate. The core in the lapillus, consisting of a single primordium, a diffuse area and the first-feeding band, was followed by 20 narrow and poorly contrasted daily increments. Thereafter, increments were wide and well-defined, and, finally became less distinct, but still homogenous after c. 53 dph. The mean increment width increased to the 29th increment and stayed relatively constant up to the 35th increment and then, gradually declined to the edge of the otolith. Wild juveniles were aged from 69 to 178 dph and hatched from the 15 February to 2 September. Growth rate was estimated from the adjusted linear regression of L_B on age: L_B = 4·37 + 0·44A (r² = 0·60), where A = age. The radius of the core and the regularity and resolution of the increments showed some differences between reared and wild fish. These results are of value for the further study of early life traits and recruitment of C. molitorella.

Study on female breast cancer imaging screening consultation network in Guangdong Province, China

OBJECTIVE

This study aimed to construct breast cancer image screening consultation network (BISCN) that connects all levels of medical institutions in Guangdong Province.

MATERIALS AND METHODS

Fourteen hospitals in different cities and counties (districts) of Guang-dong were selected for breast cancer screening with imaging (breast X-ray, ultrasound, and MRI). "Breast Imaging Reporting and Data System (BI-RADS)" was taken as reference to build up image data base of breast cancer screening and BISCN that is an internet-based network platform. BISCN quality control was performed to improve the diagnostic accuracy and collaboration of members. In 2011, the BISCN members underwent breast imaging diagnosis training and conducted a questionnaire survey.

RESULTS

BISCN allowed quick, synchronous, and accurate communication and feedback of diagnostic imaging in breast cancer among all levels of medical institutions and improved the ability of breast cancer screening in the province, as well as the detection rate of early breast cancer throughout the province, especially in the grassroot units. The survey results showed that the trainees' understanding situation of the training contents before training was 2.02 ± 1.75 points. Through the study, the participants considered that the teaching contents could solve the daily diagnose problems (2.91 ± 0.70 points), the post-training scores were improved (2.88 ± 1.23 points), and highly satisfactory with the teaching contents (2.81 ± 0.53 points). All students passed the examination and were qualified for the future.

CONCLUSIONS

BISCN is of good feasibility in construction and applicability in management by raising diagnosis level of breast cancer in Guangdong Province.

Proliferation inhibition and CD4/CD8 thymocyte subset skewing by in vivo exposure of C57BL/6 mice to Ah receptor-binding 3,3',4,4'-tetrachlorobiphenyl

3,3',4,4'-Tetrachlorobiphenyl (TCB) and other Ah receptor-binding xenobiotics lead to thymus atrophy and immunosuppression, the former possibly causing the latter. In order to better understand the TCB-induced events in the murine thymus, we analyzed the effects of TCB on the proliferation capacity and maturation kinetics of different thymocyte subsets in 2-week-old C57BL/6 mice (i.e. of the Ahb-1 'dioxin-sensitive' genotype). Mice were injected with a single dose of TCB, and the development of thymocytes was followed up for 10 days using flow cytometric surface marker analysis combined with measurement of DNA content by 7-amino-actinomycin D staining. Already 2 days after exposure to TCB, fewer of the more immature thymocytes (CD4-CD8-, CD4-CD8+ alpha beta TCR-) were proliferating than in thymi from control animals. Eventually this led to a severe decrease in thymus cellularity. Moreover, a shift towards the CD4-CD8+ mature subpopulation was observed. The effects were reversible, and proliferation and CD4/CD8 subset distribution returned to normal levels within the observation period. The results are in good agreement with the data obtained previously in vitro with fetal thymus organ cultures.

A region of barley chromosome 6H harbors multiple major genes associated with net type net blotch resistance

Net type net blotch (NTNB), caused by Pyrenophora teres f. teres Drechs., is prevalent in barley growing regions worldwide. A population of 118 doubled haploid (DH) lines developed from a cross between barley cultivars 'Rika' and 'Kombar' were used to evaluate resistance to NTNB due to their differential reaction to various isolates of P. teres f. teres. Rika was resistant to P. teres f. teres isolate 15A and susceptible to isolate 6A. Conversely, Kombar was resistant to 6A, but susceptible to 15A. A progeny isolate of a 15A x 6A cross identified as 15A x 6A#4 was virulent on both parental lines. The Rika/Kombar (RK) DH population was evaluated for disease reactions to the three isolates. Isolate 15A induced a resistant:susceptible ratio of 78:40 (R:S) whereas isolate 6A induced a resistant:susceptible ratio of 40:78. All but two lines had opposite disease reactions indicating two major resistance genes linked in repulsion. Progeny isolate 15A x 6A#4 showed a resistant:susceptible ratio of 1:117 with the one resistant line also being the single line that was resistant to both 15A and 6A. An RK F(2) population segregated in a 1:3 (R:S) ratio for both 15A and 6A indicating that resistance is recessive. Molecular markers were used to identify a region on chromosome 6H that harbors the two NTNB resistance genes. This work shows that multiple NTNB resistance genes exist at the locus on chromosome 6H, and the recombinant DH line harboring the resistance alleles from both parents will be useful for the development of NTNB-resistant barley germplasm.

Chromosomal microarray mapping suggests a role for BSX and Neurogranin in neurocognitive and behavioral defects in the 11q terminal deletion disorder (Jacobsen syndrome)

We performed a prospective analysis on 14 11q- patients to determine the relationship between the degree of cognitive impairment and relative deletion size. Seventeen measures of cognitive function were assessed. All nine patients with a deletion of at least 12.1 Mb had severe global cognitive impairment, with full-scale IQ <50, whereas all five patients with smaller deletions, <or=11.8 Mb, demonstrated mild cognitive impairment, with a full-scale IQ of 63 or higher (p < 0.001). Among these five patients, the two patients with the larger deletions (11.4, 11.8 Mb) had a selective impairment in freedom from distractability compared to the three patients with smaller deletions (<or=9.1 Mb). We propose the presence of a proximal critical region that contains a gene for global cognitive function and a distal critical region that contains a gene essential for auditory attention, which may be necessary for optimizing intellectual function. The proximal critical region is 300 kb and contains three annotated genes. One of these genes, BSX, encodes a brain-specific homeobox protein that in gene-targeted mice has been shown previously to have a role in regulating locomotory behavior via BSX-expressing neurons in the hypothalamus. The distal critical region, approximately 2.2 Mb, contains 18 annotated genes. One gene in this region, Neurogranin, has been demonstrated previously in mice to be critical for synapse plasticity and long-term potentiation. Taken together, our results implicate the presence of at least two loci in distal 11q that when deleted, cause global and selective deficits in neurocognitive function. These findings have important implications for genetic counseling and potential gene-specific therapies.

In vitro and in vivo evidence for lack of endovascular remodeling by third trimester trophoblasts

The placental-decidual interaction through invading trophoblasts determines whether a physiological transformation of the uterine spiral arteries is established or not. Trophoblast-orchestrated artery remodeling is central to normal placentation. Dysregulated uteroplacental interaction and vascular remodeling are thought to be associated with the molecular events underlying the pathology of late pregnancy anomalies including preeclampsia. Although the exact gestational age at which trophoblast invasion ceases is not known, it remains unclear whether late pregnancy trophoblasts retain the ability to transform the uterine arteries. Here, we have developed a dual cell, in vitro culture system that mimics the vascular remodeling events during normal pregnancy. We demonstrate that first and third trimester trophoblasts respond differentially to interactive signals from endothelial cells when cultured on matrigel. Term primary trophoblasts or immortalized third trimester extravillous TCL1 trophoblasts not only fail to respond to signals from endothelial cells but also inhibit endothelial cell tube formation. In contrast, HTR8 cells, representing a first trimester trophoblast cell line with invasive properties, undergo spontaneous migration and synchronize with the endothelial cells in a capillary network. This disparity in behavior was confirmed in vivo using a matrigel plug assay. Poor expression of VEGF C and VEGF receptors coupled with high E-cadherin expression by term primary trophoblasts and TCL1 cells contributed to their restricted interactive and migratory properties. We further show that the kinase activity of VEGF R2 is essential for proactive crosstalk by HTR8 cells. This unique behavior of first trimester trophoblasts in the presence of endothelial cells offers a potential approach to study cell-cell interactions and to decipher modulatory components in the serum samples from adverse pregnancy outcomes.

FAP mutations destabilize transthyretin facilitating conformational changes required for amyloid formation

Functional transthyretin (TTR) can be transformed into amyloid by partial acid denaturation yielding a monomeric amyloidogenic intermediate which self-associates. The amyloidogenic intermediate has substantial beta-sheet structure with non-native but defined tertiary structure. pH-dependent proteolysis sensitivity studies have identified portions of TTR which become disordered and solvent-exposed in the amyloidogenic intermediate. These include the C-strand-loop D-strand portion of TTR which moves away from the core of the beta-sandwich fold. Mutations that are associated with early onset-amyloid disease (familial amyloidotic polyneuropathy; FAP) function by destabilizing tetrameric TTR in favour of the monomeric amyloidogenic intermediate which has a rearranged C-strand-loop D-strand region. In most cases the FAP mutations do not significantly alter the native folded structure, but instead act on the denaturation pathway by a mechanism that is not completely understood. Interestingly, mutations have also been characterized which strongly stabilize tetrameric TTR and make amyloid formation very difficult at pHs accessible in vivo.

Identification and chromosomal location of major genes for resistance to Pyrenophora teres in a doubled-haploid barley population

Net blotch, caused by Pyrenophora teres, is one of the most economically important diseases of barley worldwide. Here, we used a barley doubled-haploid population derived from the lines SM89010 and Q21861 to identify major quantitative trait loci (QTLs) associated with seedling resistance to P. teres f. teres (net-type net blotch (NTNB)) and P. teres f. maculata (spot-type net blotch (STNB)). A map consisting of simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers was used to identify chromosome locations of resistance loci. Major QTLs for NTNB and STNB resistance were located on chromosomes 6H and 4H, respectively. The 6H locus (NTNB) accounted for as much as 89% of the disease variation, whereas the 4H locus (STNB resistance) accounted for 64%. The markers closely linked to the resistance gene loci will be useful for marker-assisted selection.

Identification and mapping of SNPs from ESTs in sunflower

More than 67,000 expressed sequence tags (ESTs) have recently been generated for sunflower (Helianthus), including 44,000 from cultivated confectionery (RHA280) and oilseed (RHA801) lines of Helianthus annuus and 23,000 from drought- and salt-tolerant wild sunflowers, H. argophyllus and H. paradoxus, respectively. To create a transcript map for sunflower, we identified 605 ESTs that displayed small insertion-deletion polymorphism (SNP) variation in silico, had apparent tissue-specific expression patterns, and/or were ESTs with candidate functions in traits such as development, cell transport, metabolism, plant defense, and tolerance to abiotic stress. Primer pairs for 535 of the loci were designed from the ESTs and screened for polymorphism in recombinant inbred lines derived from a cross between the same cultivars (RHA280 x RHA801) employed for sequencing. In total, 273 of the loci amplified polymorphic products, of which 243 mapped to the 17 linkage groups previously identified for sunflower. Comparisons with previously mapped QTL revealed some cases where ESTs with putatively related functions mapped near QTLs identified in other crosses for salt tolerance and for domestication traits such as stem diameter, shattering, flowering time, and achene size.