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The current work demonstrates the synthesis and characterization of piperic acid conjugates with homochiral/heterochiral dipeptides containing phenylalanine as anti-skin cancer agents. The conjugates PA-DPhe-LPhe-OH, FC-1 ; PA-LPhe-DPhe-OH, FC-2 ; PA-DPhe-DPhe-OH, FC-3 ; and PA-DPhe-DPhe-OH, FC-4 were synthesized, characterized and assessed for cytotoxicity against melanoma cell lines of human and murine origin. Among all, PA-DPhe-DPhe-OH (FC-3) conjugate was identified as a potential cytotoxic lead against melanoma cells by delineating the anti-proliferative and anti-migratory potential together with its anti-inflammatory potential against pro-inflammatory interleukins (IL-1β, IL-6, and IL-8). Evidences from western blotting, fractionation, and immunocytochemistry experiments suggest that Stat-3 is a critical signaling molecule involved in the FC-3 mechanism of action. The results denote that FC-3 profoundly ablates Stat-3 expression, phosphorylation, and nuclear translocation. Stat-3 mRNA analysis revealed that FC-3 did not alter the transcription of Stat-3. However, in cells where proteasome mediated degradation was inhibited, FC-3 failed to check the Stat-3 expression implying that FC-3 augments the proteasomal degradation of Stat-3. Of note, FC-3 failed to reverse the IL-6 mediated hyperactivation of Stat-3 in A375 cells. Critically, in Stat-3 deficient cancer cells, the anti-clonogenic and anti-migratory potential of FC-3 was significantly subdued. Further, the in vivo efficacy of FC-3 was validated in the two-step (DMBA/TPA) chemically induced mouse skin cancer model. The FC-3 -treated cohorts of mice unveiled a significant decrease in the cumulative number of tumors besides attenuation of tumor growth with respect to the vehicle-treated mice. Lastly, in corroboration with our in vitro findings, serum collected from mice groups at various intervals during the treatment regimen demonstrated decrement in IL-1β and IL-6 levels in FC-3 treated groups compared to the vehicle-treated group. [Display omitted] • Piperic acid conjugates with homochiral/heterochiral dipeptides, PA-DPhe-LPhe-OH, FC-1 ; PA-LPhe-DPhe-OH, FC-2 ; PA-DPhe-DPhe-OH, FC-3 ; and PA-DPhe-DPhe-OH, FC-4 , were synthesized and screened for cytotoxic potential against melanoma. • FC-3 mitigates the clonogenic, migratory, and inflammatory propensity of melanoma cells. • FC-3 ablates Stat-3 expression, phosphorylation, and nuclear translocation in melanoma cells. • In vivo efficacy of FC-3 was validated in the two-step (DMBA/TPA) chemically induced mouse skin cancer model. [ABSTRACT FROM AUTHOR]

Objective CSE-1034 is a novel antibiotic adjuvant entity (AAE) with proven activity against broad range of multi-drug resistant (MDR) pathogens causing various bacterial infections. This phase 3 clinical trial was designed to evaluate the efficacy and safety of CSE-1034 therapy for the treatment of community-acquired pneumonia (CAP) patients of Pneumonia Outcomes Research Team (PORT) risk III–IV. Methods In this multi-centric, controlled, open-labeled phase 3 trial, adult patients with PORT risk III–IV CAP were randomized to receive either intravenous CSE-1034 (3 g every 12 h) or Ceftriaxone (2 g every 12 h) for 3–10 days. The primary endpoint was clinical response in clinically-evaluable (CE) population and microbiological eradication in microbiologically-evaluable (ME) population at test of cure (TOC) visits. Secondary endpoints included verification of the primary endpoints across all other visits, treatment duration and safety of patients. Results 156 patients were screened at 5 study centers of which 93 subjects were enrolled in the study and randomized in CSE-1034 and Ceftriaxone treatment arms. In CE population (n = 90), the clinical cure rates at TOC visit were 96% and 64% in CSE-1034 (n = 46) and Ceftriaxone (n = 44) treatment arms respectively (treatment difference: 32.0%; 95% CI, 15.8%–47.1%). The bacterial eradication in ME population of two treatment arms were 94% (n = 36) and 56% (n = 27) at TOC visit (treatment difference: 38.9%; 95% CI, 17.8%–57.6%). Overall, the total number of adverse events (AEs) reported in both groups were 21 (22.5%). The AEs rates reported in two treatment arms were 15.2% in CSE-1034 and 29.8% in Ceftriaxone group. Conclusion Overall assessment of clinical cure rate, microbiological eradication rate and safety assessment in this study has shown that CSE-1034 is an effective and safe option for the treatment of CAP patients of PORT risk III–IV. Moreover, the superiority of CSE-1034 over Ceftriaxone is also proven. [ABSTRACT FROM AUTHOR]

Adaptive behavior critically depends on the detection of behaviorally relevant stimuli. The anterior insular cortex (aIC) has long been proposed as a key player in the representation and integration of sensory stimuli, and implicated in a wide variety of cognitive and emotional functions. However, to date, little is known about the contribution of aIC interneurons to sensory processing. By using a combination of whole-brain connectivity tracing, imaging of neural calcium dynamics, and optogenetic modulation in freely moving mice across different experimental paradigms, such as fear conditioning and social preference, we describe here a role for aIC vasoactive intestinal polypeptide-expressing (VIP+) interneurons in mediating adaptive behaviors. Our findings enlighten the contribution of aIC VIP+ interneurons to sensory processing, showing that they are anatomically connected to a wide range of sensory-related brain areas and critically respond to behaviorally relevant stimuli independent of task and modality. [Display omitted] • aIC VIP+ INs receive inputs from a wide variety of sensory-related brain regions • aIC VIP+ INs respond to diverse sensory stimuli • Inhibition of aIC VIP+ INs reduces fear memory retrieval and social interaction • aIC VIP+ INs are functionally heterogeneous and display coding instability The mechanisms underlying the responses of specific subclasses of interneurons to sensory stimuli with potential importance for behavioral adaptations is largely unknown. Ramos-Prats et al. identify VIP+ interneurons (INs) in the anterior insular cortex (aIC) as mediators of sensory processing and adaptive behaviors, such as social preference and fear learning. [ABSTRACT FROM AUTHOR]

Mithramycin (MTR) and daunomycin are two anticancer drugs that bind reversibly to double stranded DNA with (G.C) base specificity leading to inhibition of transcription. MTR is a groove binder of DNA in the presence of a divalent cation such as Mg2+, while daunomycin intercalates in the double stranded DNA structure. In order to understand the mechanism of action of the two types of transcription inhibitor, namely, groove binder and intercalator, we have studied the effect of N-terminal tail domains in histone proteins of the nucleosome upon the association of both MTR and daunomycin with the nucleosome core particle, because the tails modulate the accessibility to nucleosome during gene expression. Using a combination of spectroscopic, thermodynamic and biochemical studies, we have shown that N-terminal intact and chopped core particles interact differently with the same ligand and the N-terminal tail domains of core histones in the nucleosome stand in the way of free access of these ligands to the nucleosomal DNA. Tryptic removal of N-terminal tail domains of core histones enhances the binding potential and accessibility of both MTR and daunomycin to nucleosomal DNA. They disassemble the nucleosome structure leading to a release of DNA, N-terminal chopped nucleosomes being more susceptible for disruption compared to N-terminal intact nucleosomes. The extent of these effects is more pronounced in case of the intercalator daunomycin. Thus, N-terminal tail domains protect the eukaryotic genome from external agents, such as anticancer drugs, and the degree of protection is dependent upon the mode of binding to DNA. [Copyright &y& Elsevier]

Mithramycin and chromomycin A3 are two anticancer antibiotics, which inhibit protein biosynthesis via transcription inhibition. They bind reversibly to DNA with (G.C) base specificity. At and above physiological pH in the absence of DNA, they form two types of complexes with Mg2+, complex I (1:1 in terms of antibiotic: Mg2+) and complex II (2:1 in terms of antibiotic: Mg2+). These are the DNA binding ligands. In vivo, the antibiotics interact with chromatin, a protein–DNA complex. In order to understand the mode of action of these antibiotics at molecular level, we have carried out spectroscopic, gel electrophoretic and UV melting studies of complex I of these antibiotics with rat liver chromatin, nucleosome core particle and DNA stripped of all chromosomal proteins. Analysis of the results has led us to propose that the antibiotic: Mg2+ complex binds to both nucleosomal and linker DNA in native chromatin. Histone proteins reduce the binding potential and accessibility of the complexes to the minor groove of (G.C) rich regions of chromosomal DNA. The antibiotic: Mg2+ complex stabilizes DNA duplex and histone- DNA contacts in chromatin fiber. It also leads to the aggregation of chromatin fibers. From a comparison of the association of the antibiotic: Mg2+ complexes with different levels of chromatin structure and their effects upon the structure, we suggest that the sugar moieties of the antibiotics play a role in the binding process. Significance of these results to understand the molecular basis of the transcription inhibition potential of the antibiotics in eukaryotes is discussed. [Copyright &y& Elsevier]

Depletion of histone H1 after covalent modification from chromatin is a key step in eukaryotic transcription initiation. We have studied the effect of depletion of linker histone H1 upon the association of transcription inhibitor, (mithramycin)2:Mg2+ complex, with chromatin. We have compared the binding characteristics of the above complex with native, H1-depleted chromatin and naked DNA. Binding site size (number of bases per ligand molecule) of the above complex to the chromosomal DNA increases upon removal of histone H1. It implies an increase in the accessibility of the ligand for the linker DNA. Spectroscopic data, and associated enthalpy and entropy values of the interaction of the complex with H1-depleted chromatin are similar to naked DNA rather than native chromatin. These results suggest that under in vivo conditions, depletion of histone H1 from transcriptionally inert native chromatin during gene activation would lead to an enhanced accessibility of linker DNA to the small ligands with the potential to inhibit transcription. [Copyright &y& Elsevier]

Multiple stresses are prevalent inside the tumor microenvironment rendering tumor growth, neighboring invasion and metastasis of the cancer cells to distant organs. NM23-H1 is the first metastasis suppressor gene identified and known to be implicated as an important regulator of stress-induced metastasis. Herein, we demonstrated that prototypical NM23-H1 expression diminished during hypoxia and serum starvation in Panc-1/MDA-MB-231 cells, but converse invasion patterns were obtained in these two diverse stresses. Supportingly, a compelling discrete difference in mRNA and protein levels of NM23-H1 was achieved in hypoxia as well as serum starvation. Knockdown of NM23-H1 activates EMT whereas the similar effects are subdued in serum starvation where NM23-H1 down-modulation prompted E-cadherin upregulation. Stable NM23-H1 expression augmented E-cadherin levels along with retardation in invadopodea formation and invasion. In hypoxia/serum starvation excess NM23-H1 effectively modulated the Twist1 promoter activity. Thus, differential regulation of NM23-H1 may corroborate/abrogate EMT depending on the nature of stress, tumor microenvironment and cellular context. [ABSTRACT FROM AUTHOR]