Investigative analysis of blood-brain barrier penetrating potential of electronic nicotine delivery systems (e-cigarettes) chemicals using predictive computational models.

INTRODUCTION: Seizures are known potential side effects of nicotine toxicity and have been reported in electronic nicotine delivery systems (ENDS, e-cigarettes) users, with the majority involving youth or young adults. AREAS COVERED: Using chemoinformatic computational models, chemicals (including flavors) documented to be present in ENDS were compared to known neuroactive compounds to predict the blood-brain barrier (BBB) penetration potential, central nervous system (CNS) activity, and their structural similarities. The literature search used PubMed/Google Scholar, through September 2023, to identify individual chemicals in ENDS and neuroactive compounds.The results show that ENDS chemicals in this study contain >60% structural similarity to neuroactive compounds based on chemical fingerprint similarity analyses. The majority of ENDS chemicals we studied were predicted to cross the BBB, with approximately 60% confidence, and were also predicted to have CNS activity; those not predicted to passively diffuse through the BBB may be actively transported through the BBB to elicit CNS impacts, although it is currently unknown. EXPERT OPINION: In lieu of in vitro and in vivo testing, this study screens ENDS chemicals for potential CNS activity and predicts BBB penetration potential using computer-based models, allowing for prioritization for further study and potential early identification of CNS toxicity.

Clonal hematopoiesis-derived therapy-related myeloid neoplasms after autologous hematopoietic stem cell transplant for lymphoid and non-lymphoid disorders.

Therapy-related myeloid neoplasms (tMN) are complications of cytotoxic therapies. Risk of tMN is high in recipients of autologous hematopoietic stem cell transplantation (aHSCT). Acquisition of genomic mutations represents a key pathogenic driver but the origins, timing and dynamics, particularly in the context of preexisting or emergent clonal hematopoiesis (CH), have not been sufficiently clarified. We studied a cohort of 1507 patients undergoing aHSCT and a cohort of 263 patients who developed tMN without aHSCT to determine clinico-molecular features unique to post-aHSCT tMN. We show that tMN occurs in up to 2.3% of patients at median of 2.6 years post-AHSCT. Age ≥ 60 years, male sex, radiotherapy, high treatment burden ( ≥ 3 lines of chemotherapy), and graft cellularity increased the risk of tMN. Time to evolution and overall survival were shorter in post-aHSCT tMN vs. other tMN, and the earlier group's mutational pattern was enriched in PPM1D and TP53 lesions. Preexisting CH increased the risk of adverse outcomes including post-aHSCT tMN. Particularly, antecedent lesions affecting PPM1D and TP53 predicted tMN evolution post-transplant. Notably, CH-derived tMN had worse outcomes than non CH-derived tMN. As such, screening for CH before aHSCT may inform individual patients' prognostic outcomes and influence their prospective treatment plans. Presented in part as an oral abstract at the 2022 American Society of Hematology Annual Meeting, New Orleans, LA, 2022.

A 3D "sandwich" co-culture system with vascular niche supports mouse embryo development from E3.5 to E7.5 in vitro.

BACKGROUND: Various methods for ex utero culture systems have been explored. However, limitations remain regarding the in vitro culture platforms used before implanting mouse embryos and the normal development of mouse blastocysts in vitro. Furthermore, vascular niche support during mouse embryo development from embryonic day (E) 3.5 to E7.5 is unknown in vitro. METHODS: This study established a three-dimensional (3D) "sandwich" vascular niche culture system with in vitro culture medium (IVCM) using human placenta perivascular stem cells (hPPSCs) and human umbilical vein endothelial cells (hUVECs) as supportive cells (which were seeded into the bottom layer of Matrigel) to test mouse embryos from E3.5 to E7.5 in vitro. The development rates and greatest diameters of mouse embryos from E3.5 to E7.5 were quantitatively determined using SPSS software statistics. Pluripotent markers and embryo transplantation were used to monitor mouse embryo quality and function in vivo. RESULTS: Embryos in the IVCM + Cells (hPPSCs + hUVECs) group showed higher development rates and greater diameters at each stage than those in the IVCM group. Embryos in the IVCM + Cells group cultured to E5.5 morphologically resembled natural egg cylinders and expressed specific embryonic cell markers, including Oct4 and Nanog. These features were similar to those of embryos developed in vivo. After transplantation, the embryos were re-implanted in the internal uterus and continued to develop to a particular stage. CONCLUSIONS: The 3D in vitro culture system enabled embryo development from E3.5 to E7.5, and the vascularization microenvironment constructed by Matrigel, hPPSCs, and hUVECs significantly promoted the development of implanted embryos. This system allowed us to further study the physical and molecular mechanisms of embryo implantation in vitro.

Novel spirooxindole alkaloid derivatives from the medicinal insect Blaps japanensis and their biological evaluation.

Blapspirooxindoles A-C (1-3), three novel spirooxindole alkaloids with a unique spiro[chromane-4,3'-indoline]-2,2'-dione motif, blapcumaranons A and B (4 and 5), two new 2-cumaranon derivatives, blapoxindoles A-J (6-15), ten new oxindole alkaloid derivatives, along with one known compound (16), were isolated from the whole bodies of Blaps japanensis. Their structures including absolute configurations were determined by using spectroscopic, X-ray crystallographic, and computational methods. Compounds 1-11 and 13 exist as racemic mixtures in nature, and their (-)- and (+)-antipodes were separated by chiral HPLC. Biological evaluations of these compounds were determined with multiple assays including anti-tumor, anti-inflammatory, and renal protection activities in vitro. Several compounds displayed effective activity in one or more assays.

Identification and interpretation of TET2 noncanonical splicing site intronic variants in myeloid neoplasm patients.

Background: DNA hypermethylation and instability due to inactivation mutations in Ten-eleven translocation 2 (TET2) is a key biomarker of hematological malignancies. This study aims at characterizing two intronic noncanonical splice-site variants, c.3954+5_3954+8delGTTT and c.3954+5G>A. Methods: We used in silico prediction tools, reverse transcription (RT)-PCR, and Sanger sequencing on blood/bone marrow-derived RNA specimens to determine the aberrant splicing. Results: In silico prediction of both variants exhibited reduced splicing strength at the TET2 intron 7 splicing donor site. RT-PCR and Sanger sequencing identified a 62-bp deletion at the exon 7, producing a frameshift mutation, p.Cys1298*. Conclusion: This study provides functional evidence for two intronic TET2 variants that cause alternative splicing and frameshift mutation.

Routine EWS Fusion Analysis in the Oncology Clinic to Identify Cancer-Specific Peptide Sequence Patterns That Span Breakpoints in Ewing Sarcoma and DSRCT.

(1) Background: EWS fusion genes are associated with Ewing sarcoma and other Ewing family tumors including desmoplastic small round tumor, DSRCT. We utilize a clinical genomics workflow to reveal real-world frequencies of EWS fusion events, cataloging events that are similar, or divergent at the EWS breakpoint. (2) Methods: EWS fusion events from our next-generation sequencing panel (NGS) samples were first sorted by breakpoint or fusion junctions to map out the frequency of breakpoints. Fusion results were illustrated as in-frame fusion peptides involving EWS and a partner gene. (3) Results: From 2471 patient pool samples for fusion analysis at the Cleveland Clinic Molecular Pathology Laboratory, we identified 182 fusion samples evolved with the EWS gene. They are clustered in several breakpoints: chr22:29683123 (65.9%), and chr22:29688595 (2.7%). About 3/4 of Ewing sarcoma and DSRCT tumors have an identical EWS breakpoint motif at Exon 7 (SQQSSSYGQQ-) fused to a specific part of FLI1 (NPSYDSVRRG or-SSLLAYNTSS), ERG (NLPYEPPRRS), FEV (NPVGDGLFKD) or WT1 (SEKPYQCDFK). Our method also worked with Caris transcriptome data, too. Our primary clinical utility is to use this information to identify neoantigens for therapeutic purposes. (4) Conclusions and future perspectives: our method allows interpretation of what peptides result from the in-frame translation of EWS fusion junctions. These sequences, coupled with HLA-peptide binding data, are used to identify potential sequences of cancer-specific immunogenic peptides for Ewing sarcoma or DSRCT patients. This information may also be useful for immune monitoring (e.g., circulating T-cells with fusion-peptide specificity) to detect vaccine candidates, responses, or residual disease.

Highly Sensitive Blocker Displacement Amplification for Detection of Low-Level JAK2V617F Variant.

BACKGROUND: Key criteria in the diagnostic workup and risk stratification for myeloproliferative neoplasms (MPN) include molecular testing for JAK2V617F and other mutant alleles. Multiple methods for quantitatively detecting nucleotide sequence changes exist, but the lower limit of detection can limit identification of the low-level allele fraction of a variant. We evaluated a recently developed blocker displacement amplification (BDA)-based quantitative PCR platform for detection and quantitation of JAK2V617F variant allele fraction (VAF). METHODS: Clinical samples were tested using BDA, next-generation sequencing (NGS), and droplet digital PCR (ddPCR) in a head-to-head comparison of sensitivity and specificity in detecting the JAK2V617F variant. In total, 112 human genomic DNA specimens previously tested for JAK2V617F gene mutation status with NGS were analyzed, including 12 samples with low-level variants with VAF ≤2%, 6 samples with VAF >2%, and 94 samples with no variant previously identified by NGS. RESULTS: BDA and ddPCR results correlated well across a range of VAFs, with both methods identifying the JAK2V617F variant down to at least 0.05% VAF. NGS of routine sequencing depth was less sensitive, identifying JAK2V617F only at 0.6% VAF. CONCLUSIONS: BDA can provide a cost-effective alternative means to identify low-level variants using instrumentation commonly found in laboratories.

Discovery of AXL Degraders with Improved Potencies in Triple-Negative Breast Cancer (TNBC) Cells.

AXL kinase is heavily involved in tumorigenesis, metastasis, and drug resistance of many cancers, and several AXL inhibitors are in clinical investigations. Recent studies demonstrated that the N-terminal distal region of AXL plays more important roles in cell invasiveness than its C-terminal kinase domain. Therefore, degradation of AXL may present a novel superior therapeutic approach than the kinase inhibitor therapy. Herein, we report the discovery of a series of new AXL PROTAC degraders. One representative compound 6n potently depletes AXL with a DC50 value of 5 nM in MDA-MB-231 TNBC cells. It also demonstrates significantly improved potencies against the AXL signaling activation, cell proliferation, migration and invasion of TNBC cells comparing with the corresponding kinase inhibitor. Moreover, the compound exhibits promising therapeutic potential both in patient-derived organoids and a xenograft mouse model of MDA-MB-231 cells.

1-Methyl-3-((4-(quinolin-4-yloxy)phenyl)amino)-1H-pyrazole-4-carboxamide derivatives as new rearranged during Transfection (RET) kinase inhibitors capable of suppressing resistant mutants in solvent-front regions.

REarranged during Transfection (RET) is a validated target for anticancer drug discovery and two selective RET inhibitors were approved by US FDA in 2020. However, acquired resistance mediated by secondary mutations in the solvent-front region of the kinase (e.g. G810C/S/R) becomes a major challenge for selective RET inhibitor therapies. Herein, we report a structure-based design of 1-methyl-3-((4-(quinolin-4-yloxy)phenyl)amino)-1H-pyrazole-4-carboxamide derivatives as new RET kinase inhibitors which are capable of suppressing the RETG810 C/R resistant mutants. One of the representative compounds, 8q, potently suppressed wild-type RET kinase with an IC50 value of 13.7 nM. It also strongly inhibited the proliferation of BaF3 cells stably expressing various oncogenic fusions of RET kinase with solvent-front mutations, e.g. CCDC6-RETG810C, CCDC6-RETG810R, KIF5B-RETG810C and KIF5B-RETG810R, with IC50 values of 15.4, 53.2, 54.2 and 120.0 nM, respectively. Furthermore, 8q dose-dependently inhibited the activation of RET and downstream signals and obviously triggered apoptosis in Ba/F3-CCDC6-RETG810 C/R cells. The compound also exhibited significant anti-tumor efficacy with a tumor growth inhibition (TGI) value of 66.9% at 30 mg/kg/day via i. p. in a Ba/F3-CCDC6-RETG810C xenograft mouse model. Compound 8q may be utilized as a lead compound for drug discovery combating acquired resistance against selective RET inhibitor therapies.

Global Screening and Functional Identification of Major HSPs Involved in PVY Infection in Potato.

HSP40 (also known as DnaJ), HSP70, and HSP90 are major heat shock protein (HSP) families that play critical roles in plant growth and development and stress adaption. Recently, several members of the three HSP families were reported to be widely involved in the plant host-virus interactions. However, their global expression profiles and core members recruited by viruses are largely unknown. In this study, a total of 89 StDnaJs were identified from a genome-wide survey, and their classification, phylogenetic relationships, chromosomal locations, and gene duplication events were further analyzed. Together with 20 StHSP70s and 7 StHSP90s previously identified in the potato genome, the global expression patterns of the members in 3 HSP families were investigated in 2 potato cultivars during Potato virus Y (PVY) infection using RNA-seq data. Of them, 16 genes (including 8 StDnaJs, 6 StHSP70s, and 2 StHSP90s) were significantly up- or downregulated. Further analysis using qRT-PCR demonstrated that 7 of the 16 genes (StDnaJ06, StDnaJ17, StDnaJ21, StDnaJ63, StHSP70-6, StHSP70-19, and StHSP90.5) were remarkably upregulated in the potato cultivar 'Eshu 3' after PVY infection, implying their potential roles in the potato-PVY compatible interaction. Subsequent virus-induced gene silencing (VIGS) assays showed that silencing of the homologous genes of StDnaJ17, StDnaJ21, StHSP70-6, and StHSP90.5 in Nicotiana. benthamiana plants dramatically reduced the accumulation of PVY, which indicated the four genes may function as susceptibility factors in PVY infection. This study provides candidate genes for exploring the mechanism of potato-PVY compatible interaction and benefits breeding work aiming to produce new cultivars with the ability to grow healthily under PVY infection.

Design, Synthesis, and Biological Evaluation of 2-Formyl Tetrahydronaphthyridine Urea Derivatives as New Selective Covalently Reversible FGFR4 Inhibitors.

Aberrant FGF19/FGFR4 signaling is an oncogenic driver force for the development of human hepatocellular carcinoma (HCC). A series of 2-formyl tetrahydronaphthyridine urea derivatives were designed and synthesized as new covalently reversible inhibitors of FGFR4. The representative compound 9ka exhibited an IC50 value of 5.4 nM against FGFR4 and demonstrated extraordinary kinome selectivity. Compound 9ka also exhibited good oral pharmacokinetic properties with an AUC(0-t) value of 38 950.06 h·ng/mL, a T1/2 value of 3.06 h, and an oral bioavailability of 50.97%, at an oral dose of 25 mg/kg in Sprague-Dawley (SD) rats. Furthermore, compound 9ka induced significant tumor regressions in a xenograft mouse model of Hep3B2.1-7 HCC cell line without an obvious sign of toxicity upon 30 mg/kg oral administration. Compound 9ka may serve as a promising lead compound for further anticancer drug development.

Investigation of Covalent Warheads in the Design of 2-Aminopyrimidine-based FGFR4 Inhibitors.

Covalent kinase inhibitors are rapidly emerging as a class of therapeutics with clinical benefits. Herein we report a series of selective 2-aminopyrimidine-based fibroblast growth factor receptor 4 (FGFR4) inhibitors exploring different types of cysteine-targeting warheads. The structure-activity relationship study revealed that the chemically tuned warheads α-fluoro acrylamide, vinylsulfonamide, and acetaldehyde amine were suitable as covalent warheads for the design of selective FGFR4 inhibitors. Compounds 6a, 6h, and 6i selectively suppressed FGFR4 enzymatic activity with IC50 values of 53 ± 18, 45 ± 11, and 16 ± 4 nM, respectively, while sparing FGFR1/2/3. X-ray crystal structure and MALDI-TOF studies demonstrated that compound 6h bearing the α-fluoro acrylamide binds to FGFR4 with an irreversible binding mode, whereas compound 6i with an acetaldehyde amine binds to FGFR4 with a reversible covalent mode. 6h and 6i might provide some fundamental structural information for the rational design of new selective FGFR4 inhibitors.

Clinical and Pathologic Spectrum of DDX41-Mutated Hematolymphoid Neoplasms.

OBJECTIVES: This study seeks to further characterize the clinicopathologic spectrum of DDX41-mutated hematolymphoid malignancies. METHODS: We identified DDX41 mutations from a cohort of known or suspected hematologic disorders and reviewed the corresponding clinical, genetic, phenotypic, and morphologic findings. RESULTS: DDX41 mutations were identified in 20 (1.4%) of 1,371 cases, including 8 cases of acute myeloid leukemia (AML), 5 cases of myelodysplastic syndrome (MDS), 2 cases of therapy-related MDS/AML, 1 case of primary myelofibrosis, 1 case of chronic myeloid leukemia, 1 case of clonal cytopenia of uncertain significance (CCUS), 1 case of T-cell large granular lymphocytic leukemia (T-LGL), and 1 case of multiple myeloma. DDX41-mutated neoplasms were morphologically heterogeneous with a median cellularity of 20% (range, 10%-100%). Megakaryocyte dysplasia occurred in 7 (35%) of 20 cases and trilineage dysplasia in 1 (5%). Frequently comutated genes include a second, somatic DDX41 mutation (8/19, 42%) followed by mutations in TET2 (20%), DNMT3A (20%), ASXL1 (20%), and CUX1 (20%). Karyotypes were noncomplex in 17 (89%) of 19. CONCLUSIONS: This report extends the spectrum of DDX41-mutated disorders to include CCUS, T-LGL, and plasma cell disorders. The morphologic features are heterogeneous and nonspecific, highlighting the importance of DDX41 testing during routine workup of hematolymphoid neoplasms.

Smoke Chemistry, In Vitro Cytotoxicity, and Genotoxicity Demonstrates Enhanced Toxicity of Cigarillos Compared With Cigarettes.

There has been limited toxicity testing of cigarillos, including comparison to cigarettes. This study compared the smoke chemistry and the cytotoxic and genotoxic potential of 10 conventional cigarettes and 10 cigarillos based on the greatest market share. Whole smoke and total particulate matter (TPM) were generated using the Canadian Intense and International Organization for Standardization puffing protocols. Tobacco-specific nitrosamines, carbonyls, and polycyclic aromatic hydrocarbons were measured using gas chromatography-mass spectrometry. TPM smoke extracts were used for the in vitro assays. Cytotoxicity was assessed in human bronchial epithelial continuously cultured cell line cells using the neutral red uptake assay. Genotoxic potential was assessed using the micronucleus (human lung adenocarcinoma continuously cultured cell line cells), Ames, and thymidine kinase assays. TPM from all cigarillos tested was more cytotoxic than cigarettes. Micronucleus formation was significantly greater for cigarillos compared with cigarettes at the highest dose of TPM, with or without rat liver S9 fraction. In the Ames test +S9, both tobacco products exhibited significant dose-dependent increases in mutation frequency, indicating metabolic activation is required for genotoxicity. In the thymidine kinase assay +S9, cigarillos showed a significantly enhanced mutation frequency although both tobacco products were positive. The levels of all measured polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines, and carbonyls (except acrolein) were significantly greater in cigarillos than cigarettes. The Canadian Intense puffing protocol demonstrated increased smoke constituent levels compared with International Organization for Standardization. Even though the gas vapor phase was not tested, the results of this study showed that under the tested conditions the investigated cigarillos showed greater toxicity than comparator cigarettes. This study found that there is significantly greater toxicity in the tested U.S. marketed cigarillos than cigarettes for tobacco constituent levels, cytotoxicity, and genotoxicity. These findings are important for understanding the human health toxicity from the use of cigarillos relative to cigarettes and for building upon knowledge regarding harm from cigarillos to inform risk mitigation strategies.

Diagnostic Utility of a Custom 34-Gene Anchored Multiplex PCR-Based Next-Generation Sequencing Fusion Panel for the Diagnosis of Bone and Soft Tissue Neoplasms With Identification of Novel USP6 Fusion Partners in Aneurysmal Bone Cysts.

CONTEXT.­: Bone and soft tissue tumors are heterogeneous, diagnostically challenging, and often defined by gene fusions. OBJECTIVE.­: To present our experience using a custom 34-gene targeted sequencing fusion panel. DESIGN.­: Total nucleic acid extracted from formalin-fixed, paraffin-embedded (FFPE) tumor specimens was subjected to open-ended, nested anchored multiplex polymerase chain reaction and enrichment of 34 gene targets, thus enabling detection of known and novel fusion partners. RESULTS.­: During a 12-month period, 147 patients were tested as part of routine clinical care. Tumor percentage ranged from 10% to 100% and turnaround time ranged from 3 to 15 (median, 7.9) days. The most common diagnostic groups were small round blue cell tumors, tumors of uncertain differentiation, fibroblastic/myofibroblastic tumors, and adipocytic tumors. In-frame fusion transcripts were identified in 64 of 142 cases sequenced (45%): in 62 cases, the detection of a disease-defining fusion confirmed the morphologic impression; in 2 cases, a germline TFG-GPR128 polymorphic fusion variant was detected. Several genes in the panel partnered with multiple fusion partners specific for different diagnoses, for example, EWSR1, NR4A3, FUS, NCOA2, and TFE3. Interesting examples are presented to highlight how fusion detection or lack thereof was instrumental in establishing accurate diagnoses. Novel fusion partners were detected for 2 cases of solid aneurysmal bone cysts (PTBP1-USP6, SLC38A2-USP6). CONCLUSIONS.­: Multiplex detection of fusions in total nucleic acid purified from FFPE specimens facilitates diagnosis of bone and soft tissue tumors. This technology is particularly useful for morphologically challenging entities and in the absence of prior knowledge of fusion partners, and has the potential to discover novel fusion partners.

Neolignans and Norlignans from Insect Medicine Polyphaga plancyi and Their Biological Activities.

Ten neolignans or norlignans (1-10) including eight new compounds were isolated from the whole bodies of Polyphaga plancyi Bolivar. Their structures were identified by spectroscopic data. Compounds 3, 4, 8, and 9 are racemates indicated by chiral HPLC analysis. Chiral separation followed by ECD calculations allowed to clarify the absolute configurations of all the antipodes. All the new compounds were evaluated for their biological properties toward extracellular matrix in rat renal proximal tubular cells, human cancer cells (K562, A549, and Huh7), EV71, ROCK2, JAK3, DDR1, and coagulation.

Design, synthesis, and Structure-Activity Relationships (SAR) of 3-vinylindazole derivatives as new selective tropomyosin receptor kinases (Trk) inhibitors.

Neurotrophic receptor tyrosine kinase (NTRK) fusions are oncogenic drivers for a variety of adult and pediatric tumors, validated by the US FDA approval of small molecular Trk inhibitors Larotrectinib (1, LOXO-101) and Entrectinib (2). However, gene mutation mediated resistance becomes a major challenge for Trk inhibitor therapies. Herein, we report the design, synthesis and Structure-Activity Relationship investigation of a series of 3-vinylindazole derivatives as new Trk inhibitors with low nanomolar potencies. A representative compound, 7mb, binds to TrkA/B/C with Kd values of 1.6, 3.1 and 4.9 nM, and suppresses their kinase functions with IC50 values of 1.6, 2.9 and 2.0 nM, respectively, but is obviously less potent for the majority of a panel of 403 wild-type kinases in a KINOMEscan selectivity investigation. The compound also potently suppresses proliferation of a panel of BaF3 cells stably transformed with NTRK fusions with IC50 values in low nM ranges. Additionally, the compound exhibits strong inhibition against the Larotrectinib-resistant cells with NTRK1-G667C or NTRK3-G696A mutations with IC50 values of 0.031 and 0.018 µM, respectively. Although the relatively poor oral bioavailability of 7mb will limit its further development, this compound may be utilized a lead molecule for further structural optimization.

Sulfur and nitrogen-containing compounds from the whole bodies of Blaps japanensis.

Pipajiains H-J (1-3), three new phenolic derivatives with an unusual sulfone group, pipajiamides A-C (4-6), three new amide derivatives, pipajiaine A (7), one new imidazole analogue, and pipajiaine B (8), a pair of new pyrrolidine derivatives, along with three known compounds were isolated from the insect Blaps japanensis. Their structures were identified by spectroscopic and computational methods. Chiral HPLC was used to separate the (-)- and (+)-antipodes of 4 and 8. Biological activities of all the new compounds against extracellular matrix in rat renal proximal tubular cells, human cancer cells (A549, Huh-7, and K562), COX-2, ROCK1, and JAK3 were evaluated. The results show that compounds 2, (+)-4, and (-)-4 are active against kidney fibrosis, whereas, compound 9 is active toward human cancer cells, inflammation, and JAK3 kinase.

Ansamycin derivatives from the marine-derived Streptomyces sp. SCSGAA 0027 and their cytotoxic and antiviral activities.

Fourteen ansamycin derivatives including seven new herbimycins G-L (1-6) and divergolide O (7), and seven known analogues were isolated from a culture broth of the marine-derived Streptomyces sp. SCSGAA 0027. Their complete structures were determined by detailed analysis of spectroscopic data and quantum chemical calculations. Compounds 1-5 and 7 featured an additional eight-membered O-heterocycle that has rarely been reported for ansamycins, and the Z,Z- and E,E-configurations for Δ2,Δ4 were reported for the first time in geldanamycin analogues. Compound 1 exhibited weak inhibition activity towards Hsp90α with an IC50 value of 96 µM, 2-5 showed mild cytotoxicity against four human cancer cell lines with IC50 values ranging from 13 µM to 86 µM, and 7 had moderate anti-HSV-1 activity with an IC50 value of 19 µM and very weak cytotoxicity towards Vero cell. The possible biosynthetic pathways for 1-5 were proposed. And their structure-bioactivity relationship was also discussed.

Targeted next generation sequencing (NGS) to classify melanocytic neoplasms.

This study piloted a pan-solid-tumor next generation sequence (NGS)-based laboratory developed test as a diagnostic aid in melanocytic tumors. 31 cases (4 "epithelioid" nevi, 5 blue nevi variants, 7 Spitz tumors [3 benign and 4 malignant] and 15 melanomas) were evaluated. All tumors [median diameter 7 mm (range 4-15 mm); median thickness 2.25 mm (range 0.25-12 mm)] yielded satisfactory results. The number of small nucleotide variants/tumor was significantly different between melanoma (median 18/tumor, range 4-71) and all other lesions (median 8/tumor, range 3-17) (P < 0.004) and malignant (median 16/tumor, range 4-71) vs benign lesions (median 7/tumor, range 3-14) (P = 0.01). BRAF, MET, NTRK1, and ROS fusions only occurred in benign Spitz tumors; EML4 fusion, BRAF, MAP2K1 and TERT mutations occurred in malignant Spitz tumors and/or melanoma. Amplifications and NRAS and NF1 mutations only occurred in melanoma. Most melanomas contained >1 pathogenic alteration. Developed NGS-based criteria correctly classified all malignant lesions in this series. 10/12 cases showed concordance with FISH; consensus diagnosis agreed with NGS classification in FISH-non-concordant cases. This pilot study suggests that NGS may be an effective diagnostic adjunct comparable to FISH, but further studies with larger numbers of cases are needed.