Palladium-Catalyzed gem-Difluoroallylation Reaction between Aryltributyltin and Bromodifluoromethylated Alkenes.

A robust Stille gem-difluoroallylation of arylstannanes with 3-bromo-3,3-difluoropropenes has been established. The catalyst was found to exert critical effect on the reaction chemoselectivity. By using Pd(OH)2/C as the catalyst, a series of 3-(hetero)aryl/vinyl-3,3-difluoropropenes were obtained in high efficiency with α-substitution regioselectivity. The reaction has a broad substrate scope, and various substitution patterns were well tolerated in both substrates. Notably, the reaction can be easily extended to late-stage gem-difluoroallylation of many bioactive molecules with good chemoselectivity.

Visible Light-Promoted Phosphine-Catalyzed Difluoroalkylation of Arenes and Heterocycles.

A visible light-promoted difluoroalkylation reaction of arenes or heterocycles, using triaryl phosphine as the catalyst and difluoroalkyl iodide as the alkylating agent, is presented. The strategy is highlighted by photocatalyst-free, mild reaction conditions and a broad substrate scope. Mechanistic experiments indicate that this reaction involves a radical-chain process that is initiated by an electron donor-acceptor complex formed from difluoroalkyl iodide and phosphine.

A subgroup of microRNAs defines PTEN-deficient, triple-negative breast cancer patients with poorest prognosis and alterations in RB1, MYC, and Wnt signaling.

BACKGROUND: Triple-negative breast cancer (TNBC) represents a heterogeneous group of ER- and HER2-negative tumors with poor clinical outcome. We recently reported that Pten-loss cooperates with low expression of microRNA-145 to induce aggressive TNBC-like lesions in mice. To systematically identify microRNAs that cooperate with PTEN-loss to induce aggressive human BC, we screened for miRNAs whose expression correlated with PTEN mRNA levels and determined the prognostic power of each PTEN-miRNA pair alone and in combination with other miRs. METHODS: Publically available data sets with mRNA, microRNA, genomics, and clinical outcome were interrogated to identify miRs that correlate with PTEN expression and predict poor clinical outcome. Alterations in genomic landscape and signaling pathways were identified in most aggressive TNBC subgroups. Connectivity mapping was used to predict response to therapy. RESULTS: In TNBC, PTEN loss cooperated with reduced expression of hsa-miR-4324, hsa-miR-125b, hsa-miR-381, hsa-miR-145, and has-miR136, all previously implicated in metastasis, to predict poor prognosis. A subgroup of TNBC patients with PTEN-low and reduced expression of four or five of these miRs exhibited the worst clinical outcome relative to other TNBCs (hazard ratio (HR) = 3.91; P < 0.0001), and this was validated on an independent cohort (HR = 4.42; P = 0.0003). The PTEN-low/miR-low subgroup showed distinct oncogenic alterations as well as TP53 mutation, high RB1-loss signature and high MYC, PI3K, and ß-catenin signaling. This lethal subgroup almost completely overlapped with TNBC patients selected on the basis of Pten-low and RB1 signature loss or ß-catenin signaling-high. Connectivity mapping predicted response to inhibitors of the PI3K pathway. CONCLUSIONS: This analysis identified microRNAs that define a subclass of highly lethal TNBCs that should be prioritized for aggressive therapy.

From Anilines to Aryl Ethers: A Facile, Efficient, and Versatile Synthetic Method Employing Mild Conditions.

We have developed a simple and direct method for the synthesis of aryl ethers by reacting alcohols/phenols (ROH) with aryl ammonium salts (ArNMe3+ ), which are readily prepared from anilines (ArNR'2 , R'=H or Me). This reaction proceeds smoothly and rapidly (within a few hours) at room temperature in the presence of a commercially available base, such as KOt Bu or KHMDS, and has a broad substrate scope with respect to both ROH and ArNR'2 . It is scalable and compatible with a wide range of functional groups.

Cross-Coupling of Organolithium with Ethers or Aryl Ammonium Salts by C-O or C-N Bond Cleavage.

Various aryl-, alkenyl-, and/or alkyllithium species reacted smoothly with aryl and/or benzyl ethers with cleavage of the inert C-O bond to afford cross-coupled products, catalyzed by commercially available [Ni(cod)2 ] (cod=1,5-cyclooctadiene) catalysts with N-heterocyclic carbene (NHC) ligands. Furthermore, the coupling reaction between the aryllithium compounds and aryl ammonium salts proceeded under mild conditions with C-N bond cleavage in the presence of a [Pd(PPh3 )2 Cl2 ] catalyst. These methods enable selective sequential functionalizations of arenes having both C-N and C-O bonds in one pot.

Stannyl-Lithium: A Facile and Efficient Synthesis Facilitating Further Applications.

We have developed a highly efficient, practical, polycyclic aromatic hydrocarbon (PAH)-catalyzed synthesis of stannyl lithium (Sn-Li), in which the tin resource (stannyl chloride or distannyl) is rapidly and quantitatively transformed into Sn-Li reagent at room temperature without formation of any (toxic) byproducts. The resulting Sn-Li reagent can be stored at ambient temperature for months and shows high reactivity toward various substrates, with quantitative atom efficiency.

Validation of the prognostic gene portfolio, ClinicoMolecular Triad Classification, using an independent prospective breast cancer cohort and external patient populations.

INTRODUCTION: Using genome-wide expression profiles of a prospective training cohort of breast cancer patients, ClinicoMolecular Triad Classification (CMTC) was recently developed to classify breast cancers into three clinically relevant groups to aid treatment decisions. CMTC was found to be both prognostic and predictive in a large external breast cancer cohort in that study. This study serves to validate the reproducibility of CMTC and its prognostic value using independent patient cohorts. METHODS: An independent internal cohort (n = 284) and a new external cohort (n = 2,181) were used to validate the association of CMTC between clinicopathological factors, 12 known gene signatures, two molecular subtype classifiers, and 19 oncogenic signalling pathway activities, and to reproduce the abilities of CMTC to predict clinical outcomes of breast cancer. In addition, we also updated the outcome data of the original training cohort (n = 147). RESULTS: The original training cohort reached a statistically significant difference (p < 0.05) in disease-free survivals between the three CMTC groups after an additional two years of follow-up (median = 55 months). The prognostic value of the triad classification was reproduced in the second independent internal cohort and the new external validation cohort. CMTC achieved even higher prognostic significance when all available patients were analyzed (n = 4,851). Oncogenic pathways Myc, E2F1, Ras and ß-catenin were again implicated in the high-risk groups. CONCLUSIONS: Both prospective internal cohorts and the independent external cohorts reproduced the triad classification of CMTC and its prognostic significance. CMTC is an independent prognostic predictor, and it outperformed 12 other known prognostic gene signatures, molecular subtype classifications, and all other standard prognostic clinicopathological factors. Our results support further development of CMTC portfolio into a guide for personalized breast cancer treatments.

CDK4/6 inhibitors and the pRB-E2F1 axis suppress PVR and PD-L1 expression in triple-negative breast cancer.

Immune-checkpoint (IC) modulators like the poliovirus receptor (PVR) and programmed death ligand 1 (PD-L1) attenuate innate and adaptive immune responses and are potential therapeutic targets for diverse malignancies, including triple-negative breast cancer (TNBC). The retinoblastoma tumor suppressor, pRB, controls cell growth through E2F1-3 transcription factors, and its inactivation drives metastatic cancer, yet its effect on IC modulators is contentious. Here, we show that RB-loss and high E2F1/E2F2 signatures correlate with expression of PVR, CD274 (PD-L1 gene) and other IC modulators and that pRB represses whereas RB depletion and E2F1 induce PVR and CD274 in TNBC cells. Accordingly, the CDK4/6 inhibitor, palbociclib, suppresses both PVR and PD-L1 expression. Palbociclib also counteracts the effect of CDK4 on SPOP, leading to its depletion, but the overall effect of palbociclib is a net reduction in PD-L1 level. Hydrochloric acid, commonly used to solubilize palbociclib, counteracts its effect and induces PD-L1 expression. Remarkably, lactic acid, a by-product of glycolysis, also induces PD-L1 as well as PVR. Our results suggest a model in which CDK4/6 regulates PD-L1 turnover by promoting its transcription via pRB-E2F1 and degradation via SPOP and that the CDK4/6-pRB-E2F pathway couples cell proliferation with the induction of multiple innate and adaptive immunomodulators, with direct implications for cancer progression, anti-CDK4/6- and IC-therapies.

Thinking (Metastasis) outside the (Primary Tumor) Box.

The metastasis of tumor cells into vital organs is a major cause of death from diverse types of malignancies [...].

Distinct shared and compartment-enriched oncogenic networks drive primary versus metastatic breast cancer.

Metastatic breast-cancer is a major cause of death in women worldwide, yet the relationship between oncogenic drivers that promote metastatic versus primary cancer is still contentious. To elucidate this relationship in treatment-naive animals, we hereby describe mammary-specific transposon-mutagenesis screens in female mice together with loss-of-function Rb, which is frequently inactivated in breast-cancer. We report gene-centric common insertion-sites (gCIS) that are enriched in primary-tumors, in metastases or shared by both compartments. Shared-gCIS comprise a major MET-RAS network, whereas metastasis-gCIS form three additional hubs: Rho-signaling, Ubiquitination and RNA-processing. Pathway analysis of four clinical cohorts with paired primary-tumors and metastases reveals similar organization in human breast-cancer with subtype-specific shared-drivers (e.g. RB1-loss, TP53-loss, high MET, RAS, ER), primary-enriched (EGFR, TGFß and STAT3) and metastasis-enriched (RHO, PI3K) oncogenic signaling. Inhibitors of RB1-deficiency or MET plus RHO-signaling cooperate to block cell migration and drive tumor cell-death. Thus, targeting shared- and metastasis- but not primary-enriched derivers offers a rational avenue to prevent metastatic breast-cancer.

[Serum changes of adiponectin, insulin resistance and their correlation in endometrial cancer patients].

OBJECTIVE: To explore changes of serum adiponectin and insulin resistance in patients with endometrial cancer and to evaluate the clinical significance and correlation. METHODS: The serum levels of adiponectin and fasting insulin were determined by ELISA, electro-chemilluminometry and radioimmunoassay in 35 patients with endometrial cancer [all patients divided into two groups, A1 group belonged to without postmenopausal when first visiting (n = 20), A2 group belonged to postmenopausal when first visiting (n = 15)] and 30 cases of health control. The result of homeostasis model assessment-insulin resistance (HOMA-IR) index was calculated. RESULTS: The levels of adiponectin in A1 group was lower than that of health control group [(6.7 ± 1.1) versus (10.0 ± 1.4) ng/L, P < 0.05], and HOMA-IR was higher than that of health control group (3.5 ± 1.8 versus 1.1 ± 0.7, P < 0.05). While there were not significant difference between A2 group and health control group (P > 0.05). Adiponectin and insulin resistance was negatively correlated (r = -0.389, P < 0.05). CONCLUSION: Adiponectin reducing and insulin resistance in reproductive age patients may be the independent factors to promote endometrial cancers.

Conjugation of the glutelin hydrolysates-glucosamine by transglutaminase and functional properties and antioxidant activity of the products.

A novel mixture of glycopeptides was prepared from corn glutelin and glucosamine (GlcN). The functional properties and antioxidative activities of this mixture were investigated. Corn glutelin was limited hydrolyzed by Alcalase, and then its hydrolysates were glycosylated with GlcN by transglutaminase (TGase) to modify its main and side chain, respectively. Under the optimized conditions, the content of GlcN conjugated to peptides was 81.98 ± 1.98 mg/g glutelin peptides. According to electrospray ionization mass spectrometry (ESI-MS) analysis, there are two types of glycopeptides in the mixture, TGase and non-enzymatic glycated counterparts. Compared with original glutelin, the glycosylated glutelin hydrolysates exhibited better solubility in the pH range of 2-11 and other functional properties except foaming stability. Meanwhile, it is more easily digested by pepsin and trypsin, and possessed excellent antioxidative activities. It also exhibited cytoprotective effects and intracellular ROS scavenging activities in LO2 cells subjected to oxidative stress by oxidation with ethanol solution.

A new gene expression signature, the ClinicoMolecular Triad Classification, may improve prediction and prognostication of breast cancer at the time of diagnosis.

INTRODUCTION: When making treatment decisions, oncologists often stratify breast cancer (BC) into a low-risk group (low-grade estrogen receptor-positive (ER+)), an intermediate-risk group (high-grade ER+) and a high-risk group that includes Her2+ and triple-negative (TN) tumors (ER-/PR-/Her2-). None of the currently available gene signatures correlates to this clinical classification. In this study, we aimed to develop a test that is practical for oncologists and offers both molecular characterization of BC and improved prediction of prognosis and treatment response. METHODS: We investigated the molecular basis of such clinical practice by grouping Her2+ and TN BC together during clustering analyses of the genome-wide gene expression profiles of our training cohort, mostly derived from fine-needle aspiration biopsies (FNABs) of 149 consecutive evaluable BC. The analyses consistently divided these tumors into a three-cluster pattern, similarly to clinical risk stratification groups, that was reproducible in published microarray databases (n = 2,487) annotated with clinical outcomes. The clinicopathological parameters of each of these three molecular groups were also similar to clinical classification. RESULTS: The low-risk group had good outcomes and benefited from endocrine therapy. Both the intermediate- and high-risk groups had poor outcomes, and their BC was resistant to endocrine therapy. The latter group demonstrated the highest rate of complete pathological response to neoadjuvant chemotherapy; the highest activities in Myc, E2F1, Ras, ß-catenin and IFN-γ pathways; and poor prognosis predicted by 14 independent prognostic signatures. On the basis of multivariate analysis, we found that this new gene signature, termed the "ClinicoMolecular Triad Classification" (CMTC), predicted recurrence and treatment response better than all pathological parameters and other prognostic signatures. CONCLUSIONS: CMTC correlates well with current clinical classifications of BC and has the potential to be easily integrated into routine clinical practice. Using FNABs, CMTC can be determined at the time of diagnostic needle biopsies for tumors of all sizes. On the basis of using public databases as the validation cohort in our analyses, CMTC appeared to enable accurate treatment guidance, could be made available in preoperative settings and was applicable to all BC types independently of tumor size and receptor and nodal status. The unique oncogenic signaling pathway pattern of each CMTC group may provide guidance in the development of new treatment strategies. Further validation of CMTC requires prospective, randomized, controlled trials.

Expression of Abl interactor 1 and its prognostic significance in breast cancer: a tissue-array-based investigation.

Abl interactor 1 (Abi1) is an adaptor protein involved in cell migration. Previous in vitro work suggested that Abi1 is a regulator of breast cancer proliferation, migration, and invasion. In the present study, we explore the expression of Abi1 and its downstream effector phospho-Akt (p-Akt) in a series of breast cancers and correlate their expression with clinicopathological and survival data. Using tissue microarrays, 988 patients with invasive breast carcinoma were evaluated by immunohistochemistry. Statistical correlation was performed to determine associations between Abi1 and p-Akt expression and standard breast clinicopathological factors. The prognostic value of Abi1 and p-Akt for disease-free (DFS) and overall survival (OS) was also evaluated. Abi1 expression was demonstrated in 33.7% (314/933) of invasive carcinomas, while p-Akt was expressed in 46.7% (441/944). There was a significant association between Abi1 and p-Akt expression (P=0.001). Abi1 expression showed significant positive correlation with older age at diagnosis and the Ki67 index. Most importantly, it was demonstrated to be an independent predictor of both DFS and OS (HR = 1.6 and 1.5, P<0.001, respectively). There was no association between p-Akt expression and survival. To the best of our knowledge, this is the first study evaluating Abi1 expression in a large group of breast cancers. Our analysis demonstrated that tumors expressing high levels of Abi1 are significantly associated with early recurrence and worse survival on multivariate analysis. This suggests that Abi1 expression has potential as a molecular marker to refine outcome prediction in breast cancer patients.

Clinical relevance of DNA microarray analyses using archival formalin-fixed paraffin-embedded breast cancer specimens.

BACKGROUND: The ability of gene profiling to predict treatment response and prognosis in breast cancers has been demonstrated in many studies using DNA microarray analyses on RNA from fresh frozen tumor specimens. In certain clinical and research situations, performing such analyses on archival formalin fixed paraffin-embedded (FFPE) surgical specimens would be advantageous as large libraries of such specimens with long-term follow-up data are widely available. However, FFPE tissue processing can cause fragmentation and chemical modifications of the RNA. A number of recent technical advances have been reported to overcome these issues. Our current study evaluates whether or not the technology is ready for clinical applications. METHODS: A modified RNA extraction method and a recent DNA microarray technique, cDNA-mediated annealing, selection, extension and ligation (DASL, Illumina Inc) were evaluated. The gene profiles generated from FFPE specimens were compared to those obtained from paired fresh fine needle aspiration biopsies (FNAB) of 25 breast cancers of different clinical subtypes (based on ER and Her2/neu status). Selected RNA levels were validated using RT-qPCR, and two public databases were used to demonstrate the prognostic significance of the gene profiles generated from FFPE specimens. RESULTS: Compared to FNAB, RNA isolated from FFPE samples was relatively more degraded, nonetheless, over 80% of the RNA samples were deemed suitable for subsequent DASL assay. Despite a higher noise level, a set of genes from FFPE specimens correlated very well with the gene profiles obtained from FNAB, and could differentiate breast cancer subtypes. Expression levels of these genes were validated using RT-qPCR. Finally, for the first time we correlated gene expression profiles from FFPE samples to survival using two independent microarray databases. Specifically, over-expression of ANLN and KIF2C, and under-expression of MAPT strongly correlated with poor outcomes in breast cancer patients. CONCLUSION: We demonstrated that FFPE specimens retained important prognostic information that could be identified using a recent gene profiling technology. Our study supports the use of FFPE specimens for the development and refinement of prognostic gene signatures for breast cancer. Clinical applications of such prognostic gene profiles await future large-scale validation studies.

Preparation of Sulfamates and Sulfamides Using a Selective Sulfamoylation Agent.

Sulfamates and sulfamides are prevalent in biological molecules, but their universal synthetic methods are limited. We herein report a sulfamoylation agent with high solubility and shelf stability. Various sulfamates and sulfamides can be synthesized directly from alcohols or amines by employing this agent with high selectivity and high yields. This protocol was also successfully used for late-stage sulfamoylation of pharmaceuticals containing a hydroxyl or amino group.

Up-regulation of apoptosis by gonadotrophin-releasing hormone agonist in cultures of endometrial cells from women with symptomatic myomas.

BACKGROUND: The aim of the present study was to evaluate the effect of gonadotrophin-releasing hormone agonist (GnRH-a), which is widely used in the medical treatment of symptomatic myomas, on the rate of endometrial cell apoptosis in cultures from women with symptomatic myomas. METHODS: The study included 36 women with symptomatic myomas without endometrial hyperplasia or endometrial carcinoma, and 22 controls. Endometrial biopsy specimens were obtained from all subjects. Levels of apoptosis were examined in epithelial endometrial cell cultures before and after incubation with GnRH-a (triptorelin). The percentage of apoptotic cells was evaluated using the terminal deoxynucleotidyl transferase-mediated d-UTP nick end labeling assay and flow cytometry was used to evaluate Annexin V levels. RESULTS: Levels of spontaneous apoptosis were significantly lower in endometrial cultures from patients with symptomatic myomas than in those from control subjects (P < 0.01). Concentrations as low as 10(-7) M GnRH-a enhanced apoptosis in endometrial cultures from patients with symptomatic myomas (3.48% +/- 0.27% apoptotic cells in untreated samples and 25.45 +/- 0.95% in cells treated with 10(-7) M GnRH-a; P <0.01). The percentage of apoptotic cells also increased when cultures from control women were treated with GnRH-a (8.10 +/- 0.18% in untreated samples and 15.29 +/- 2.30% in treated samples; P <0.01). Levels of apoptosis were dependent on both dose of GnRH-a and time of treatment. CONCLUSIONS: GnRH-a stimulates apoptosis in endometrial cells from patients with symptomatic myomas and this could, at least in part, account for the therapeutic action of GnRH-a.

Troglitazone suppresses telomerase activity independently of PPARgamma in estrogen-receptor negative breast cancer cells.

BACKGROUND: Breast cancer is one the highest causes of female cancer death worldwide. Many standard chemotherapeutic agents currently used to treat breast cancer are relatively non-specific and act on all rapidly dividing cells. In recent years, more specific targeted therapies have been introduced. It is known that telomerase is active in over 90% of breast cancer tumors but inactive in adjacent normal tissues. The prevalence of active telomerase in breast cancer patients makes telomerase an attractive therapeutic target. Recent evidence suggests that telomerase activity can be suppressed by peroxisome proliferator activated receptor gamma (PPARgamma). However, its effect on telomerase regulation in breast cancer has not been investigated. METHODS: In this study, we investigated the effect of the PPARgamma ligand, troglitazone, on telomerase activity in the MDA-MB-231 breast cancer cell line. Real time RT-PCR and telomerase activity assays were used to evaluate the effect of troglitazone. MDA-MB-231 cells had PPARgamma expression silenced using shRNA interference. RESULTS: We demonstrated that troglitazone reduced the mRNA expression of hTERT and telomerase activity in the MDA-MB-231 breast cancer cell line. Troglitazone reduced telomerase activity even in the absence of PPARgamma. In agreement with this result, we found no correlation between PPARgamma and hTERT mRNA transcript levels in breast cancer patients. Statistical significance was determined using Pearson correlation and the paired Student's t test. CONCLUSIONS: To our knowledge, this is the first time that the effect of troglitazone on telomerase activity in breast cancer cells has been investigated. Our data suggest that troglitazone may be used as an anti-telomerase agent; however, the mechanism underlying this inhibitory effect remains to be determined.

N-Phenyl-cyclo-hexa-necarboxamide.

In the title compound, C(13)H(17)NO, the cyclo-hexane ring adopts a chair conformation and the amide C(=O)-N moiety is almost coplanar with the phenyl ring [C-N-C-O = 4.1 (2)°]. In the crystal, mol-ecules are linked to form a C(4) infinite [001] chain via N-H⋯O hydrogen bonds, unlike the cyclic motif seen in related structures.

Modeling germline mutations in pineoblastoma uncovers lysosome disruption-based therapy.

Pineoblastoma is a rare pediatric cancer induced by germline mutations in the tumor suppressors RB1 or DICER1. Presence of leptomeningeal metastases is indicative of poor prognosis. Here we report that inactivation of Rb plus p53 via a WAP-Cre transgene, commonly used to target the mammary gland during pregnancy, induces metastatic pineoblastoma resembling the human disease with 100% penetrance. A stabilizing mutation rather than deletion of p53 accelerates metastatic dissemination. Deletion of Dicer1 plus p53 via WAP-Cre also predisposes to pineoblastoma, albeit with lower penetrance. In silico analysis predicts tricyclic antidepressants such as nortriptyline as potential therapeutics for both pineoblastoma models. Nortriptyline disrupts the lysosome, leading to accumulation of non-functional autophagosome, cathepsin B release and pineoblastoma cell death. Nortriptyline further synergizes with the antineoplastic drug gemcitabine to effectively suppress pineoblastoma in our preclinical models, offering new modality for this lethal childhood malignancy.