RESUMEN
BACKGROUND: The 12-gene Oncotype DX Colon Recurrence Score® result quantifies the recurrence risk in stage II/III colon cancer (CC). This real-world study investigated stage II CC patients whose treatment decisions incorporated the Recurrence Score® (RS) result. MATERIALS AND METHODS: This retrospective analysis of a prospectively designed cohort included all stage II, mismatch repair-proficient CC patients who underwent 12-gene testing through Clalit between January 2011 and December 2016 and had available data with a minimum 3-year follow-up. RESULTS: The analysis included 938 patients {median age 68 [interquartile range (IQR) 60-76] years; 96% T3 tumors}. The median RS was 26 (IQR 19-33) and the three RS categories (0-29, 30-40, 41-100) included 65%, 24%, and 11% of patients, respectively. Chemotherapy (CT) use differed significantly between the three RS categories (14%, 36%, and 60%, respectively; P < 0.001). The CT and observation-only groups were imbalanced with worse clinicopathologic characteristics in the former. Among observation-only patients, Kaplan-Meier (KM) estimates for recurrence-free interval (RFI) and CC-specific survival (CCSS) differed significantly between the three RS categories (P < 0.001). Clinical outcomes by treatment (CT versus observation) within each RS category revealed no differences in RFI and CCSS in the RS 0-29 and 30-40 categories. In contrast, in the RS 41-100 category, the difference in RFI trended toward significance (P = 0.066), and for CCSS, a statistically significant difference was observed, with better outcomes among CT-treated patients (P = 0.035). CONCLUSIONS: RS results are prognostic in stage II CC. Among RS 41-100 patients, outcomes were better in CT-treated versus observation-only patients despite worse clinicopathologic characteristics, suggesting that CT confers clinical benefit in high-risk patients.
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Neoplasias del Colon , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Humanos , Neoplasias del Colon/genética , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Femenino , Masculino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Recurrencia Local de Neoplasia/genética , Resultado del TratamientoRESUMEN
OBJECTIVE: A3 adenosine receptor (A3AR) is overexpressed in the skin and peripheral blood mononuclear cells of psoriasis patients. We investigated the efficacy/safety of piclidenoson (CF101), an orally bioavailable A3AR agonist that inhibits IL-17 and IL-23 production in keratinocytes, in moderate-to-severe plaque psoriasis. METHODS: The randomized, placebo- and active-controlled, double-blind phase 3 COMFORT-1 trial randomized patients (3:3:3:2) to piclidenoson 2 mg BID, piclidenoson 3 mg BID, apremilast 30 mg BID or placebo. At Week 16, patients in the placebo arm were re-randomized (1:1:1) to piclidenoson 2 mg BID, piclidenoson 3 mg BID or apremilast 30 mg BID. The primary end point was the proportion of patients achieving ≥75% improvement in Psoriasis Area and Severity Index (PASI) from baseline (PASI-75) at Week 16 versus placebo. RESULTS: A total of 529 patients were randomized and received ≥1 dose of study medication (safety population). The efficacy analysis population for the primary end point included 426 patients (piclidenoson 2 mg BID, 127; piclidenoson 3 mg BID, 103; apremilast, 118; placebo, 78). Piclidenoson at 2 and 3 mg BID exhibited similar efficacy. The primary end point was met with the 3 mg BID dose: PASI 75 rate of 9.7% versus 2.6% for piclidenoson versus placebo, p = 0.037. The PASI responses with piclidenoson continued to increase throughout the study period in a linear manner. At week 32, analysis in the per-protocol population showed that a greater proportion of patients in the piclidenoson 3 mg BID arm (51/88, 58.0%) achieved improvement from baseline in Psoriasis Disability Index (PDI) compared to apremilast (59/108, 55.1%), and the test for noninferiority trended towards significance (p = 0.072). The safety/tolerability profile of piclidenoson was excellent and superior to apremilast. CONCLUSIONS: Piclidenoson demonstrated efficacy responses that increased over time alongside a favourable safety profile. These findings support its continued clinical development as a psoriasis treatment (ClinicalTrials.gov identifier: NCT03168256).
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Psoriasis , Talidomida , Humanos , Psoriasis/tratamiento farmacológico , Masculino , Método Doble Ciego , Femenino , Persona de Mediana Edad , Adulto , Talidomida/análogos & derivados , Talidomida/uso terapéutico , Talidomida/efectos adversos , Talidomida/administración & dosificación , Índice de Severidad de la Enfermedad , Adenosina/análogos & derivadosRESUMEN
BACKGROUND: Physicians and other health care personnel rely on the peer-reviewed biomedical literature as a key source for making clinical decisions. Thus, ensuring that the nonclinical and clinical findings published in biomedical journals are reported accurately and clearly, without undue influence from commercial interests, is essential. Accordingly, beginning in the mid-1990s and continuing to the present, various organizations, including the International Committee of Medical Journal Editors, the American Medical Association, the Council of Science Editors, the American Medical Writers Association, and the International Society for Medical Publication Professionals, have published guidelines to strengthen and uphold ethical standards in biomedical communications. SCOPE: A task force of staff members from the AXIS group of companies reviewed these and other guidelines to assess the need for a good publication practices (GPP) document specific to medical communications agencies. As this review demonstrated an unmet need, the task force was charged with developing GPP guidelines for the AXIS group of agencies in the United States. FINDINGS: Although such guidelines have been previously published on behalf of medical journal editors and publishers, medical writers, academic centers, and pharmaceutical companies, there has been no prior publication in the peer-reviewed literature of good publication practices for medical communications agencies, which face unique challenges in negotiating a balance among authors, sponsoring companies, and biomedical publishers. CONCLUSION: This article presents and discusses these GPP guidelines. To our knowledge, this is the first publication of guidelines developed from the perspective of a medical communications agency.
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Guías como Asunto , Revisión de la Investigación por Pares/normasRESUMEN
TAP tags and dot blot analysis have been used to measure the amounts of RNA polymerase II transcription proteins in crude yeast extracts. The measurements showed comparable amounts of RNA polymerase II, TFIIE, and TFIIF, lower levels of TBP and TFIIB, and still lower levels of Mediator and TFIIH. These findings are consistent with the presumed roles of the transcription proteins, but do not support the idea of their recruitment in a single large complex to RNA polymerase II promoters. The approach employed here can be readily extended to quantitative analysis of the entire yeast proteome.
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Técnicas Genéticas , ARN Polimerasa II/genética , Saccharomyces cerevisiae/genética , Transcripción Genética , División Celular , Electroforesis en Gel de Poliacrilamida , Glutatión Transferasa/metabolismo , Immunoblotting , Inmunoglobulina G/metabolismo , Unión Proteica , Saccharomyces cerevisiae/metabolismo , Factor de Transcripción TFIIB , Factor de Transcripción TFIID , Factores de Transcripción/biosíntesis , Factores de Transcripción TFII/biosíntesisRESUMEN
The TATA box-binding protein (TBP) recognizes its target sites (TATA boxes) by indirectly reading the DNA sequence through its conformation effects (indirect readout). Here, we explore the molecular mechanisms underlying indirect readout of TATA boxes by TBP by studying the binding of TBP to adenovirus major late promoter (AdMLP) sequence variants, including alterations inside as well as in the sequences flanking the TATA box. We measure here the dissociation kinetics of complexes of TBP with AdMLP targets and, by phase-sensitive assay, the intrinsic bending in the TATA box sequences as well as the bending of the same sequence induced by TBP binding. In these experiments we observe a correlation of the kinetic stability to sequence changes within the TATA recognition elements. Comparison of the kinetic data with structural properties of TATA boxes in known crystalline TBP/TATA box complexes reveals several "signals" for TATA box recognition, which are both on the single base-pair level, as well as larger DNA tracts within the TATA recognition element. The DNA bending induced by TBP on its binding sites is not correlated to the stability of TBP/TATA box complexes. Moreover, we observe a significant influence on the kinetic stability of alteration in the region flanking the TATA box. This effect is limited however to target sites with alternating TA sequences, whereas the AdMLP target, containing an A tract, is not influenced by these changes.
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Proteínas de Unión al ADN/metabolismo , ADN/genética , ADN/metabolismo , TATA Box/genética , Factores de Transcripción/metabolismo , Adenoviridae/genética , Emparejamiento Base/genética , Secuencia de Bases , Sitios de Unión , Secuencia de Consenso/genética , ADN/química , Proteínas de Unión al ADN/química , Semivida , Cinética , Mutación/genética , Conformación de Ácido Nucleico , Docilidad , Unión Proteica , Especificidad por Sustrato , Proteína de Unión a TATA-Box , Termodinámica , Factores de Transcripción/química , LevadurasRESUMEN
Both direct and indirect readouts are utilized when the trp repressor binds to its operators. Here, we use gel-electrophoretic methods to examine the role played by direct and indirect readouts in the interaction of the repressor with a non-canonical binding site, similar to the mtr operator, and named trpGG. The stability and affinity of the 1:1 complexes of the trp repressor with this non-canonical site are lower than those of the 1:1 complexes formed with either the natural consensus sequence or a consensus sequence found in a selection experiment. We attribute this to the inability of the trpGG target to make the same number of water-mediated hydrogen bonds as canonical trp binding sites. On the other hand, the 2:1 complex of the repressor with trpGG has high stability and affinity, similar to that of the 2:1 complex with a consensus sequence found by a selection experiment. The bend angle induced on the trpGG target by the binding of one repressor molecule is 27 degrees, which is similar to that measured in other 1:1 complexes with the repressor. The angle for the 2:1 complex is significantly larger (43 degrees versus 30 degrees in other 2:1 complexes). We present evidence suggesting that the deleterious effect of the sequence substitution in trpGG is compensated by the increased bend angle in the 2:1 complex. These observations demonstrate that indirect readout may complement for direct readout in determining the nature of the interaction between trp repressor and its binding sites.
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Proteínas Bacterianas , Proteínas Represoras/metabolismo , Sitios de Unión/genética , Secuencia de Consenso/genética , Proteínas de Unión al ADN/metabolismo , Enlace de Hidrógeno , Conformación Molecular , Estructura Molecular , Regiones Operadoras Genéticas/genéticaRESUMEN
DNA containing short periodic stretches of adenine residues (known as A-tracts), which are aligned with the helical repeat, exhibit a pronounced macroscopic curvature. This property is thought to arise from the cumulative effects of a distinctive structure of the A-tract. It has also been observed by gel electrophoresis that macroscopic curvature is largely retained when inosine bases are introduced singly into A-tracts but decreases abruptly for pure I-tracts. The structural basis of this effect is unknown. Here we describe X-ray and gel electrophoretic analyses of several oligomers incorporating adenine or inosine bases or both. We find that macroscopic curvature is correlated with a distinctive base-stacking geometry characterized by propeller twisting of the base-pairs. Regions of alternating adenine and inosine bases display large propeller twisting comparable to that of pure A-tracts, whereas the values observed for pure I-tracts are significantly smaller. We also observe in the crystal structures that propeller twist leads to close cross-strand contacts between amino groups from adenine and cytosine bases, indicating an attractive NH-N interaction, which is analogous to the NH-O interaction proposed for A-tracts. This interaction also occurs between adenine bases across an A-T step and may explain in part the different behavior of A-T versus T-A steps in the context of A-tract-induced curvature. We also note that hydration patterns may contribute to propeller-twisted conformation. Based on the present data and other structural and biophysical studies, we propose that DNA macroscopic curvature is related to the structural invariance of A-tract and A-tract-like regions conferred by high propeller twist, cross-strand interactions and characteristic hydration. The implications of these findings to the mechanism of DNA bending are discussed.
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ADN/química , Conformación de Ácido Nucleico , Adenina/química , Cristalografía por Rayos X , Electroforesis en Gel de Poliacrilamida , Inosina/química , Modelos Moleculares , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/química , Agua/químicaRESUMEN
The interaction of trp repressor with its DNA targets is unusual in that specific recognition in this system does not rely exclusively on direct hydrogen bonds to the DNA bases that are crucial for sequence-specific recognition. It has been suggested that trp operators are mainly recognized by water-mediated interactions and by structural recognition of DNA deformability. Here we study the effect of the central dinucleotide on the mode of interaction of the trp repressor with its binding sites. The study was carried out on two consensus sequences: (1) trpTA, the consensus of naturally occurring trp binding sites, containing a T-A step between the two hexameric half-site sequences, ACTAGT; (2) trpAC, a consensus sequence derived from a functional selection study, containing a central A-C step. We show that the identity of the central dinucleotide does not affect the interaction of the first trp repressor molecule with the primary DNA target site, however, it influences the assembly of additional repressor molecules at adjacent sites. Central A-C steps stabilize tandem binding, whereas T-A steps destabilize it. It has been previously suggested that in vivo regulation of trp operators is due to their differential ability to bind multiple repressor molecules. The observations presented here support this model. We ascribe this ability to two sequence-dependent factors which act together: the identity and number of half-site sequences, recognized by water-mediated hydrogen bonds, and the ability of the intervening dinucleotides to form direct bidentate hydrogen bonds to the repressor. Furthermore, we measured the intrinsic and the induced bending of trp operators by the repressor. We find that the operators are straight in their free form, bent by 23 degrees when bound by a single trp repressor molecule, and bent by 30 degrees when bound by two repressor molecules.