Tctp, a unique Ing5-binding partner, inhibits the chromatin binding of Enok in Drosophila.

The MOZ/MORF histone acetyltransferase complex is highly conserved in eukaryotes and controls transcription, development, and tumorigenesis. However, little is known about how its chromatin localization is regulated. Inhibitor of growth 5 (ING5) tumor suppressor is a subunit of the MOZ/MORF complex. Nevertheless, the in vivo function of ING5 remains unclear. Here, we report an antagonistic interaction between Drosophila Translationally controlled tumor protein (TCTP) (Tctp) and ING5 (Ing5) required for chromatin localization of the MOZ/MORF (Enok) complex and H3K23 acetylation. Yeast two-hybrid screening using Tctp identified Ing5 as a unique binding partner. In vivo, Ing5 controlled differentiation and down-regulated epidermal growth factor receptor signaling, whereas it is required in the Yorkie (Yki) pathway to determine organ size. Ing5 and Enok mutants promoted tumor-like tissue overgrowth when combined with uncontrolled Yki activity. Tctp depletion rescued the abnormal phenotypes of the Ing5 mutation and increased the nuclear translocation of Ing5 and chromatin binding of Enok. Nonfunctional Enok promoted the nuclear translocation of Ing5 by reducing Tctp, indicating a feedback mechanism between Tctp, Ing5, and Enok to regulate histone acetylation. Therefore, Tctp is essential for H3K23 acetylation by controlling the nuclear translocation of Ing5 and chromatin localization of Enok, providing insights into the roles of human TCTP and ING5-MOZ/MORF in tumorigenesis.

Proteomics reveals NNMT as a master metabolic regulator of cancer-associated fibroblasts.

High-grade serous carcinoma has a poor prognosis, owing primarily to its early dissemination throughout the abdominal cavity. Genomic and proteomic approaches have provided snapshots of the proteogenomics of ovarian cancer1,2, but a systematic examination of both the tumour and stromal compartments is critical in understanding ovarian cancer metastasis. Here we develop a label-free proteomic workflow to analyse as few as 5,000 formalin-fixed, paraffin-embedded cells microdissected from each compartment. The tumour proteome was stable during progression from in situ lesions to metastatic disease; however, the metastasis-associated stroma was characterized by a highly conserved proteomic signature, prominently including the methyltransferase nicotinamide N-methyltransferase (NNMT) and several of the proteins that it regulates. Stromal NNMT expression was necessary and sufficient for functional aspects of the cancer-associated fibroblast (CAF) phenotype, including the expression of CAF markers and the secretion of cytokines and oncogenic extracellular matrix. Stromal NNMT expression supported ovarian cancer migration, proliferation and in vivo growth and metastasis. Expression of NNMT in CAFs led to depletion of S-adenosyl methionine and reduction in histone methylation associated with widespread gene expression changes in the tumour stroma. This work supports the use of ultra-low-input proteomics to identify candidate drivers of disease phenotypes. NNMT is a central, metabolic regulator of CAF differentiation and cancer progression in the stroma that may be therapeutically targeted.

A metabolite-derived protein modification integrates glycolysis with KEAP1-NRF2 signalling.

Mechanisms that integrate the metabolic state of a cell with regulatory pathways are necessary to maintain cellular homeostasis. Endogenous, intrinsically reactive metabolites can form functional, covalent modifications on proteins without the aid of enzymes1,2, and regulate cellular functions such as metabolism3-5 and transcription6. An important 'sensor' protein that captures specific metabolic information and transforms it into an appropriate response is KEAP1, which contains reactive cysteine residues that collectively act as an electrophile sensor tuned to respond to reactive species resulting from endogenous and xenobiotic molecules. Covalent modification of KEAP1 results in reduced ubiquitination and the accumulation of NRF27,8, which then initiates the transcription of cytoprotective genes at antioxidant-response element loci. Here we identify a small-molecule inhibitor of the glycolytic enzyme PGK1, and reveal a direct link between glycolysis and NRF2 signalling. Inhibition of PGK1 results in accumulation of the reactive metabolite methylglyoxal, which selectively modifies KEAP1 to form a methylimidazole crosslink between proximal cysteine and arginine residues (MICA). This posttranslational modification results in the dimerization of KEAP1, the accumulation of NRF2 and activation of the NRF2 transcriptional program. These results demonstrate the existence of direct inter-pathway communication between glycolysis and the KEAP1-NRF2 transcriptional axis, provide insight into the metabolic regulation of the cellular stress response, and suggest a therapeutic strategy for controlling the cytoprotective antioxidant response in several human diseases.

Development of a Dual-Factor Activatable Covalent Targeted Photoacoustic Imaging Probe for Tumor Imaging.

Photoacoustic imaging (PAI) is an emerging modality in biomedical imaging with superior imaging depth and specificity. However, PAI still has significant limitations, such as the background noise from endogenous chromophores. To overcome these limitations, we developed a covalent activity-based PAI probe, NOx-JS013, targeting NCEH1. NCEH1, a highly expressed and activated serine hydrolase in aggressive cancers, has the potential to be employed for the diagnosis of cancers. We show that NOx-JS013 labels active NCEH1 in live cells with high selectivity relative to other serine hydrolases. NOx-JS013 also presents its efficacy as a hypoxia-responsive imaging probe in live cells. Finally, NOx-JS013 successfully visualizes aggressive prostate cancer tumors in mouse models of PC3, while being negligibly detected in tumors of non-aggressive LNCaP mouse models. These findings show that NOx-JS013 has the potential to be used to develop precision PAI reagents for detecting metastatic progression in various cancers.

Age-Dependent Clinicopathological Characteristics of Patients with T1b Papillary Thyroid Carcinoma: Implications for the Possibility of Active Surveillance.

BACKGROUND: Active surveillance (AS) of low-risk T1a papillary thyroid carcinoma (PTC) is generally accepted as an alternative to immediate surgery. The cut-off in the size criterion for AS has recently been extended in select individuals, especially older patients. We evaluated the clinicopathological differences of T1b PTC according to age to investigate the possibility of AS in older patients. PATIENTS AND METHODS: From a cohort study of 1269 patients undergoing lobectomy for PTC, 1223 PTC patients with T1 stage disease (tumor ≤ 2 cm) were enrolled. The clinicopathological characteristics between T1a and T1b patients according to age were analyzed. RESULTS: Among the 1223 T1 cases, 918 (75.1%) were T1a (≤ 1 cm) and 305 (34.9%) T1b (> 1 and ≤ 2 cm). T1b PTC was associated with male sex, minimal extrathyroidal extension, lymphovascular invasion, occult central lymph node (LN) metastasis, and a higher number of metastatic LNs than T1a. However, in patients over 55 years of age, the clinicopathological features of the patients with T1a and T1b PTC were not significantly different except for minimal extrathyroidal extension, although many clinicopathological differences were observed in patients under 55 years of age. CONCLUSION: The clinicopathological features of patients with T1b PTC over 55 years of age are similar to those with T1a PTC and less aggressive than those with T1b PTC under 55 years of age. These findings suggest that AS may be possible in patients with T1b PTC over 55 years of age without high-risk features on preoperative examinations.

Patterns of Occult Metastasis to Level Va and Vb in Clinically Lateral Node-Positive Papillary Thyroid Carcinoma.

BACKGROUND: The optimal extent of therapeutic lateral neck dissection (ND) in papillary thyroid carcinoma (PTC) continues to be debated. We analyzed the frequency, patterns, and predictive factors of occult level Va and Vb metastasis in clinically lateral node-positive PTC patients. METHODS: We reviewed the data of PTC patients who underwent thyroidectomy and therapeutic lateral ND from level II to V between May 2008 and August 2020. In our study, 46 patients without clinically positive metastatic lymph nodes (LNs) at level V on the preoperative evaluation were included to analyze occult metastasis at level Va and Vb, respectively. Patient demographics, including age, sex, distribution of pathologic LNs, and characteristics of the primary tumors, were reviewed. In addition, clinicopathologic factors associated with occult level Va and Vb metastasis were analyzed. RESULTS: Of the 46 patients, 14 (30.4%) patients had occult metastases at level Vb. No occult metastases were found at level Va. Clinically positive level II metastasis (p = 0.015) and simultaneous level II, III, and IV metastases (p = 0.010) in the preoperative evaluation were significantly associated with occult level Vb metastasis. Patients without LN metastasis at level IV or with three or fewer metastatic LNs in the lateral neck never had occult LN metastases at level Vb. CONCLUSIONS: Occult metastasis at level Va is rare in PTC with lateral LN metastasis. Occult metastasis at level Vb may occur in PTC patients with multilevel involvement, including level II and/or four or more lateral LN metastases.

Ultrasensitive, multiplexed chemoproteomic profiling with soluble activity-dependent proximity ligation.

Chemoproteomic methods can report directly on endogenous, active enzyme populations, which can differ greatly from measures of transcripts or protein abundance alone. Detection and quantification of family-wide probe engagement generally requires LC-MS/MS or gel-based detection methods, which suffer from low resolution, significant input proteome requirements, laborious sample preparation, and expensive equipment. Therefore, methods that can capitalize on the broad target profiling capacity of family-wide chemical probes but that enable specific, rapid, and ultrasensitive quantitation of protein activity in native samples would be useful for basic, translational, and clinical proteomic applications. Here we develop and apply a method that we call soluble activity-dependent proximity ligation (sADPL), which harnesses family-wide chemical probes to convert active enzyme levels into amplifiable barcoded oligonucleotide signals. We demonstrate that sADPL coupled to quantitative PCR signal detection enables multiplexed "writing" and "reading" of active enzyme levels across multiple protein families directly at picogram levels of whole, unfractionated proteome. sADPL profiling in a competitive format allows for highly sensitive detection of drug-protein interaction profiling, which allows for direct quantitative measurements of in vitro and in vivo on- and off-target drug engagement. Finally, we demonstrate that comparative sADPL profiling can be applied for high-throughput molecular phenotyping of primary human tumor samples, leading to the discovery of new connections between metabolic and proteolytic enzyme activity in specific tumor compartments and patient outcomes. We expect that this modular and multiplexed chemoproteomic platform will be a general approach for drug target engagement, as well as comparative enzyme activity profiling for basic and clinical applications.

SHMT2 Induces Stemness and Progression of Head and Neck Cancer.

Various enzymes in the one-carbon metabolic pathway are closely related to the development of tumors, and they can all be potential targets for cancer therapy. Serine hydroxymethyltransferase2 (SHMT2), a key metabolic enzyme, is very important for the proliferation and growth of cancer cells. However, the function and mechanism of SHMT2 in head and neck cancer (HNC) are not clear. An analysis of The Cancer Genome Atlas (TCGA) data showed that the expression of SHMT2 was higher in tumor tissue than in normal tissue, and its expression was significantly associated with male sex, aggressive histological grade, lymph node metastasis, distant metastasis, advanced TNM stage, and lymphovascular invasion in HNC. SHMT2 knockdown in FADU and SNU1041 cell lines significantly inhibited cell proliferation, colony formation, migration, and invasion. Additionally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses using TCGA data revealed that SHMT2 was closely related to cancer stem cell regulation and maintenance. Furthermore, we found that silencing SHMT2 inhibited the expression of stemness markers and tumor spheroid formation compared with a control group. On the contrary, stemness markers were significantly increased after SHMT2 overexpression in HEP-2 cells. Interestingly, we found that knocking down SHMT2 reduced the expression of genes related to the Notch and Wnt pathways. Finally, silencing SHMT2 significantly reduced tumor growth and decreased stemness markers in a xenograft model. Taken together, our study suggests that targeting SHMT2 may play an important role in inhibiting HNC progression.

Transcriptional Regulation of GDF15 by EGR1 Promotes Head and Neck Cancer Progression through a Positive Feedback Loop.

Growth and differentiation factor 15 (GDF15), a divergent member of the transforming growth factor-ß (TGF-ß) superfamily, has been reported to be overexpressed in different kinds of cancer types. However, the function and mechanism of GDF15 in head and neck cancer (HNC) remains unclear. The Cancer Genome Atlas (TCGA) data show that the expression of GDF15 is significantly associated with tumor AJCC stage, lymph vascular invasion and tumor grade in HNC. In this study, we confirmed that knockdown of GDF15 attenuated: cell proliferation, migration and invasion via regulation of EMT through a canonical pathway; SMAD2/3 and noncanonical pathways; PI3K/AKT and MEK/ERK in HNC cell lines. Furthermore, we found that early growth response 1 (EGR1) was a transcription factor of GDF15. Interestingly, we also demonstrated that GDF15 could regulate the expression of EGR1, which meant a positive feedback loop occurred between these two factors. Moreover, combined inhibition of both GDF15 and EGR1 in a HNC mouse xenograft model showed significantly decreased tumor volume compared to inhibition of EGR1 or GDF15 alone. Our study showed that the GDF15-EGR1 signaling axis may be a good target in HNC patients.

Is an Ultrasonic and Bipolar Integrated Energy Device More Useful Than a Conventional Electric Device in Head and Neck Free Flap Reconstruction? A Prospective Comparison.

PURPOSE: Thunderbeat (TB) is an integrated energy device incorporating ultrasonic and bipolar technology that provides rapid cut and precision dissection and reliable vessel sealing compared with conventional electrosurgery (ES). The present study compared the surgical outcomes of TB and ES for harvesting the anterolateral thigh free flap (ALTFF). PATIENTS AND METHODS: The present prospective cohort study compared TB and ES in patients who had undergone head and neck reconstruction using ALTFFs. The baseline characteristics, including age, gender, body mass index, primary tumor site (recipient site), and T stage, were measured. Patients who had undergone reconstruction after previous unsuccessful head and neck cancer treatment using radiation were included in the salvage surgery group. The primary outcome variables were the harvesting time, blood loss, and flap failure. The interval until the start of an oral diet and the percutaneous endoscopic gastrostomy (PEG) insertion rate were analyzed to compare the functional outcomes. After identifying the confounding variables, multivariate approaches were used to adjust for the confounding variables. RESULTS: No significant differences were found in the demographics and disease-related factors such as age, gender, body mass index, anatomic distribution, and T stage of the primary disease, between the 2 groups. The operation time and bleeding volume were reduced by 32.4 and 33.1%, respectively, in the TB group compared with those in the control group. The postoperative drainage volume, duration, flap failure rate, and intensive care unit and total hospital stays were nearly identical between the 2 groups. No statistically significant differences were found in the functional outcomes (PEG insertion and oral diet start day) between the 2 groups. CONCLUSIONS: The results of the present study have shown that TB is a useful supportive tool for head and neck reconstruction surgery because it decreases the operation time with surgical outcomes comparable to those with conventional ES.

The most reliable time point for intact parathyroid hormone measurement to predict hypoparathyroidism after total thyroidectomy with central neck dissection to treat papillary thyroid carcinoma: a prospective cohort study.

PURPOSE: We assessed the optimal time for intact parathyroid hormone (iPTH) measurement for early detection of post-total thyroidectomy (TT) hypocalcemia in patients with papillary thyroid carcinoma (PTC). METHODS: In this single-center prospective cohort study, 143 patients who underwent TT with central neck dissection with or without lateral neck dissection for PTC were included. Biochemical profiles including iPTH, corrected total calcium, and ionized calcium within 24 h after surgery were analyzed. RESULTS: The 4-h postoperative iPTH was the most reliable predictor of post-TT transient or permanent hypoparathyroidism (cutoff for hypocalcemia was 3.75 pg/mL, AUC = 0.885, P < 0.001, sensitivity 81.6%, specificity 86.0%; cutoff for permanent hypocalcemia was 2.48 pg/mL, AUC = 0.819, P < 0.001, sensitivity 100%, specificity 57.8% calculated using ROC curves). CONCLUSIONS: The 4-h postoperative iPTH can most accurately predict hypoparathyroidism after TT with central neck dissection to treat PTC and facilitate the early discharge of low-risk postoperative hypoparathyroidism patients and decrease unnecessary overnight observation and calcium supplementation.

Effect of Urban Particulate Matter on Vocal Fold Fibrosis through the MAPK/NF-κB Signaling Pathway.

Particulate matter (PM) is an environmental exposure factor that adversely affects human health. PM is a risk factor for various diseases. However, the mechanism by which PM affects the vocal folds (VF) has not yet been evaluated. Thus, we investigated the cytotoxic effects of PM on human vocal fold fibroblasts (hVFF) and the underlying signaling pathways. hVFF were isolated from human VF. The effect of PM on hVFF, and the underlying mechanism, were analyzed using Western blot, quantitative real-time polymerase chain reaction, and flow cytometry. In addition, a histological evaluation was performed in animal experiments. Cell proliferation decreased after the PM treatment. PM increased the expression of interleukin (IL)-6 and IL-1ß. The generation of reactive oxygen species (ROS) in PM-treated hVFF and subsequent activation of the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways were confirmed. Furthermore, PM increased the expression of fibrosis-related markers and induced the accumulation of collagen in the extracellular matrix. As a result, PM exposure significantly enhances the inflammatory response on VF through the ROS-mediated activation of the MAPK and NF-κB signaling pathways. In addition, PM promotes differentiation into myofibroblasts and induces fibrosis. These results suggest that PM triggers an inflammatory reaction through ROS production and causes VF fibrosis.

In†Vivo Imaging of the Tumor-Associated Enzyme NCEH1 with a Covalent PET Probe.

Herein, we report the development of an 18 F-labeled, activity-based small-molecule probe targeting the cancer-associated serine hydrolase NCEH1. We undertook a focused medicinal chemistry campaign to simultaneously preserve potent and specific NCEH1 labeling in live cells and animals, while permitting facile 18 F radionuclide incorporation required for PET imaging. The resulting molecule, [18 F]JW199, labels active NCEH1 in live cells at nanomolar concentrations and greater than 1000-fold selectivity relative to other serine hydrolases. [18 F]JW199 displays rapid, NCEH1-dependent accumulation in mouse tissues. Finally, we demonstrate that [18 F]JW199 labels aggressive cancer tumor cells in vivo, which uncovered localized NCEH1 activity at the leading edge of triple-negative breast cancer tumors, suggesting roles for NCEH1 in tumor aggressiveness and metastasis.

Parathyroid carcinoma arising from auto-transplanted parathyroid tissue after Total Parathyroidectomy in chronic kidney disease patient: a case report.

BACKGROUND: Secondary hyperparathyroidism is a common complication in patients with chronic kidney disease that requires vigilant treatment due to its high mortality rate. Pharmacologic therapy is recommended as an initial treatment; if there is no response, a total parathyroidectomy is performed. In some cases, surgery is accompanied by auto-transplantation of parathyroid tissue. CASE PRESENTATION: The patient was diagnosed with chronic kidney disease and received a kidney transplant. However, due to rejection of the transplanted kidney, medical nephrectomy was carried out and routine hemodialysis was initiated and observed. At this time, secondary hyperparathyroidism with elevated parathyroid hormone and hyperphosphatemia developed and pharmacologic treatment was applied. However, there was no response to pharmacologic treatment; therefore, total parathyroidectomy with auto-transplantation was performed. Eight years after surgery, a growing mass was observed in the transplantation site, accompanied by an elevation of parathyroid hormone. A complete resection of the mass was performed, and the patient was diagnosed with parathyroid carcinoma. Additional adjuvant radiation therapy was ordered, and the patient is being monitored. CONCLUSIONS: This is a rare but remarkable case of parathyroid carcinoma arising from auto-transplanted parathyroid tissue after total parathyroidectomy in a patient with secondary hyperparathyroidism. We suggest caution should be taken when choosing to auto- transplant parathyroid tissue and that careful postoperative observation should be performed.

Diacylglycerol lipase disinhibits VTA dopamine neurons during chronic nicotine exposure.

Chronic nicotine exposure (CNE) alters synaptic transmission in the ventral tegmental area (VTA) in a manner that enhances dopaminergic signaling and promotes nicotine use. The present experiments identify a correlation between enhanced production of the endogenous cannabinoid 2-arachidonoylglycerol (2-AG) and diminished release of the inhibitory neurotransmitter GABA in the VTA following CNE. To study the functional role of on-demand 2-AG signaling in GABAergic synapses, we used 1,2,3-triazole urea compounds to selectively inhibit 2-AG biosynthesis by diacylglycerol lipase (DAGL). The potency and selectivity of these inhibitors were established in rats in vitro (rat brain proteome), ex vivo (brain slices), and in vivo (intracerebroventricular administration) using activity-based protein profiling and targeted metabolomics analyses. Inhibition of DAGL (2-AG biosynthesis) rescues nicotine-induced VTA GABA signaling following CNE. Conversely, enhancement of 2-AG signaling in naïve rats by inhibiting 2-AG degradation recapitulates the loss of nicotine-induced GABA signaling evident following CNE. DAGL inhibition reduces nicotine self-administration without disrupting operant responding for a nondrug reinforcer or motor activity. Collectively, these findings provide a detailed characterization of selective inhibitors of rat brain DAGL and demonstrate that excessive 2-AG signaling contributes to a loss of inhibitory GABAergic constraint of VTA excitability following CNE.

Efficacy of three proton-pump inhibitor therapeutic strategies on laryngopharyngeal reflux disease; a prospective randomized double-blind study.

OBJECTIVES: Proton-pump inhibitor (PPI) prescribing practices in laryngopharyngeal reflux disease (LPR) differ among physicians. We assessed the improvement in reflux symptom index (RSI) and reflux finding score (RFS) after treating LPR with three different regimens. DESIGN: A prospective, double-blind, randomized clinical trial. SETTING: Chungnam national university hospital in Korea. PARTICIPANTS: From July 2015 to July 2017, 100 patients with LPR included in the study. The patients were prescribed one of the following regimens for 3 months: group A, ilaprazole 10 mg, once a day (QD), n = 29; group B, ilaprazole 10 mg, twice a day (BID), n = 27; and group C, ilaprazole 10 mg BID plus mosapride citrate 5 mg three times a day (TID), n = 44. MAIN OUTCOME MEASURES: The total RSI and RFS scores and each subitems in RSI and FRS of the patients were evaluated. RESULTS: Total RFS and RSI scores improved significantly at the 3-month follow-up in all groups, and the improvements were of similar magnitudes. Regarding the RFS, the degrees of improvement in vocal cord oedema (P = 0.002) and diffuse laryngeal oedema (P = 0.003) scores differed significantly among the three groups. Moreover, overweight or obese patients in group C showed the greatest improvement in RFS. However, age had no effect on treatment efficacy. CONCLUSION: Three PPI therapeutic strategies showed similar efficacies against LPR according to total RFS and RSI scores. The addition of a prokinetic resulted in improvements in specific endoscopic findings, such as vocal cord oedema and diffuse laryngeal oedema. Furthermore, the addition of a prokinetic to PPI therapy was particularly beneficial for overweight or obese patients.

Systematic identification of genomic markers of drug sensitivity in cancer cells.

Clinical responses to anticancer therapies are often restricted to a subset of patients. In some cases, mutated cancer genes are potent biomarkers for responses to targeted agents. Here, to uncover new biomarkers of sensitivity and resistance to cancer therapeutics, we screened a panel of several hundred cancer cell lines--which represent much of the tissue-type and genetic diversity of human cancers--with 130 drugs under clinical and preclinical investigation. In aggregate, we found that mutated cancer genes were associated with cellular response to most currently available cancer drugs. Classic oncogene addiction paradigms were modified by additional tissue-specific or expression biomarkers, and some frequently mutated genes were associated with sensitivity to a broad range of therapeutic agents. Unexpected relationships were revealed, including the marked sensitivity of Ewing's sarcoma cells harbouring the EWS (also known as EWSR1)-FLI1 gene translocation to poly(ADP-ribose) polymerase (PARP) inhibitors. By linking drug activity to the functional complexity of cancer genomes, systematic pharmacogenomic profiling in cancer cell lines provides a powerful biomarker discovery platform to guide rational cancer therapeutic strategies.

Relationship Between 18F-fluorodeoxyglucose Accumulation and the BRAF V600E Mutation in Papillary Thyroid Cancer.

BACKGROUND: To determine whether 18F-fluoro-2-deoxyglucose (18F-FDG)-PET/CT is useful for predicting the BRAF V600E mutation status of a primary papillary thyroid carcinoma (PTC). METHODS: A retrospective analysis was performed in 108 patients who underwent 18F-FDG positron emission tomography-computed tomography (PET/CT) for staging before thyroidectomy and BRAF analysis in biopsy-confirmed PTC. The maximum standardized uptake value (SUVmax) of the primary tumor was calculated according to FDG accumulation. Univariate and multivariate analyses were performed to assess the association between the SUVmax and clinicopathological variables. RESULTS: The BRAF V600E mutation was detected in 71 of 108 (65.7%) patients. In all subjects, the tumor size and BRAF V600E mutation were independently related to the SUVmax according to multivariate analyses (P = 0.002 and 0.007, respectively). The SUVmax was significantly higher in tumors with the BRAF V600E mutation than in tumors with wild-type BRAF (10.24 ± 11.89 versus 4.02 ± 3.86; P = 0.007). In the tumor size >1 cm subgroup, the BRAF V600E mutation was the only factor significantly associated with the SUVmax (P = 0.016). A SUVmax cutoff level of 4.9 was determined to be significant for predicting the BRAF V600E mutation status (sensitivity 77.4%, specificity 100.0%, area under the curve 0.929; P < 0.0001) according to ROC curve analysis. CONCLUSIONS: The BRAF V600E mutation is independently associated with high 18F-FDG uptake in PTC, especially in those with a tumor size >1 cm.

Chemoproteomic Profiling of Phosphoaspartate Modifications in Prokaryotes.

Phosphorylation at aspartic acid residues represents an abundant and critical post-translational modification (PTM) in prokaryotes. In contrast to most characterized PTMs, such as phosphorylation at serine or threonine, the phosphoaspartate moiety is intrinsically labile, and therefore incompatible with common proteomic profiling methods. Herein, we report a nucleophilic, desthiobiotin-containing hydroxylamine (DBHA) chemical probe that covalently labels modified aspartic acid residues in native proteomes. DBHA treatment coupled with LC-MS/MS analysis enabled detection of known phosphoaspartate modifications, as well as novel aspartic acid sites in the E. coli proteome. Coupled with isotopic labelling, DBHA-dependent proteomic profiling also permitted global quantification of changes in endogenous protein modification status, as demonstrated with the detection of increased E. coli OmpR phosphorylation, but not abundance, in response to changes in osmolarity.