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Large cell lung carcinoma (LCLC) is one form of NSCLC that spreads more aggressively than some other forms, and it represents an unmet medical need. Here, we investigated for the first time the effect of the anti-CK2 CIGB-300 peptide in NCI-H460 cells as an LCLC model. NCI-H460 cells were highly sensitive toward CIGB-300 cytotoxicity, reaching a peak of apoptosis at 6 h. Moreover, CIGB-300 slightly impaired the cell cycle of NCI-H460 cells. The CIGB-300 interactomics profile revealed in more than 300 proteins that many of them participated in biological processes relevant in cancer. Interrogation of the CK2 subunits targeting by CIGB-300 indicated the higher binding of the peptide to the CK2α′ catalytic subunit by in vivo pull-down assays plus immunoblotting analysis and confocal microscopy. The down-regulation of both phosphorylation and protein levels of the ribonuclear protein S6 (RPS6) was observed 48 h post treatment. Altogether, we have found that NCI-H460 cells are the most CIGB-300-sensitive solid tumor cell line described so far, and also, the findings we provide here uncover novel features linked to CK2 targeting by the CIGB-300 anticancer peptide. [ABSTRACT FROM AUTHOR]

HeberFERON, a co-formulation of Interferon (IFN)-α2b and IFN-γ, has effects on skin cancer and other solid tumors. It has antiproliferative effects over glioblastoma multiform (GBM) clones and cultured cell lines, including U-87 MG. Here, we report the first label-free quantitative proteomic and phospho-proteomic analyses to evaluate changes induced by HeberFERON after 72 h incubation of U-87 MG that can explain the effect on cellular proliferation. LC-MS/MS, functional enrichment and networking analysis were performed. We identified 7627 proteins; 122 and 211 were down- and up-regulated by HeberFERON (fold change > 2; p < 0.05), respectively. We identified 23,549 peptides (5692 proteins) and 8900 phospho-peptides; 523 of these phospho-peptides (359 proteins) were differentially modified. Proteomic enrichment showed IFN signaling and its control, direct and indirect antiviral mechanisms were the main modulated processes. Phospho-proteome enrichment displayed the cell cycle as one of the most commonly targeted events together with cytoskeleton organization; translation/RNA splicing, autophagy and DNA repair, as represented biological processes. There is a high interconnection of phosphoproteins in a molecular network; mTOR occupies a centric hub with interactions with translation machinery, cytoskeleton and autophagy components. Novel phosphosites and others with unknown biological functionality in key players in the aforementioned processes were regulated by HeberFERON and involved CDK and ERK kinases. These findings open new experimental hypotheses regarding HeberFERON action. The results obtained contribute to a better understanding of HeberFERON effector mechanisms in the context of GBM treatment. [ABSTRACT FROM AUTHOR]

Coronaviruses constitute a global threat to the human population; therefore, effective pan-coronavirus antiviral drugs are required to tackle future re-emerging virus outbreaks. Protein kinase CK2 has been suggested as a promising therapeutic target in COVID-19 owing to the in vitro antiviral activity observed after both pharmacologic and genetic inhibition of the enzyme. Here, we explored the putative antiviral effect of the anti-CK2 peptide CIGB-325 on bovine coronavirus (BCoV) infection using different in vitro viral infected cell-based assays. The impact of the peptide on viral mRNA and protein levels was determined by qRT-PCR and Western blot, respectively. Finally, pull-down experiments followed by Western blot and/or mass spectrometry analysis were performed to identify CIGB-325-interacting proteins. We found that CIGB-325 inhibited both the cytopathic effect and the number of plaque-forming units. Accordingly, intracellular viral protein levels were clearly reduced after treatment of BCoV-infected cells, with CIGB-325 determined by immunocytochemistry. Pull-down assay data revealed the physical interaction of CIGB-325 with viral nucleocapsid (N) protein and a group of bona fide CK2 cellular substrates. Our findings evidence in vitro antiviral activity of CIGB-325 against bovine coronavirus as well as some molecular clues that might support such effect. Altogether, data provided here strengthen the rationale of inhibiting CK2 to treat betacoronavirus infections. [ABSTRACT FROM AUTHOR]

Background The synergistic combination of interferon (IFN) alpha-2b and IFN gamma results in more potent in vitro biological effects mediated by both IFNs. The aim of this investigation was to evaluate by first time the pharmacokinetics and pharmacodynamics of this combination in patients with mycosis fungoides. Methods An exploratory, prospective, open-label clinical trial was conducted. Twelve patients, both genders, 18 to 75 years-old, with mycosis fungoides at stages IB to III, were eligible for the study. All of them received intramuscularly a single high dose (23 × 106 IU) of a novel synergistic IFN mixture (HeberPAG®) for pharmacokinetic and pharmacodynamic studies. Serum IFN alpha-2b and IFN gamma concentrations were measured during 96 hours by commercial enzyme immunoassays (EIA) specific for each IFN. Other blood IFN-inducible markers and laboratory variables were used as pharmacodynamics and safety criteria. Results The pharmacokinetic evaluation by EIA yielded a similar pattern for both IFNs that are also in agreement with the well-known described profiles for these molecules when these are administered separately. The average values for main parameters were: Cmax: 263 and 9.3 pg/mL; Tmax: 9.5 and 6.9 h; AUC: 4483 and 87.5 pg.h/mL, half-life (t1/2): 4.9 and 13.4 h; mean residence time (MRT): 13.9 and 13.5 h, for serum IFN alpha-2b and IFN gamma, respectively. The pharmacodynamic variables were strongly stimulated by simultaneous administration of both IFNs: serum neopterin and beta-2 microglobulin levels (β2M), and stimulation of 2’-5’ oligoadenylate synthetase (OAS1) mRNA expression. The most encouraging data was the high increment of serum neopterin, 8.0 ng/mL at 48 h, not been described before for any unmodified or pegylated IFN. Additionally, β2M concentration doubled the pre-dose value at 24–48 hours. For both variables the values remained clearly upper baseline levels at 96 hours. Conclusions HeberPAG®possesses improved pharmacodynamic properties that may be very useful in the oncologic setting. Efficacy trials can be carried out to confirm these findings. [ABSTRACT FROM AUTHOR]

Tissue fibrosis is a leading cause of morbidity and mortality. Current treatments for conditions such as hepatic fibrosis have been unsuccessful. The growth hormone relasing peptide 6 (GHRP6) is endowed with cardioprotective actions but its antifibrotic effect had not been anticipated. We examined the GHRP6 ability to prevent and revert liver cirrhosis after induction in Wistar rats by a subcutaneous administration of CCl4. GHRP6 effects were examined after concomitant and delayed administration to toxic respectively. The percentages of hepatic fat, fibrosis, nodularity and septae thickness were histologically and morphometrically determined. Ascitis and portal dilation were judged by ultrasound and serum biochemical profile and oxidative stress parameters determined. Mechanistic involvement of selective gene/proteins was assessed by RT-PCR and immunohistochemistry. Microarrays showed gene expression profiles of GHRP6-treated liver samples on CapitalBio Rat Genome Oligo Array. GHRP6 concomitant intervention prevented in more than 85% parenchymal fibrotic induration (p < 0.0001) and therapeutic administration for only 15 days allowed for 37% fibrotic clearance (p = 0.0004) with more than 30% reduction of septae thickness (p = 0.0011). The 60 days GHRP6 administration scheme produced a 75% reduction of the fibrotic area with more than 60% reduction of nodularity. GHRP6 reduced oxidative damage enhancing the activity of antioxidant enzymes. Vimentin and alpha smooth muscle actin immunodetection profile indicated GHRP6 reduced the number of activated stellate cells. GHRP6 administration reduced fibrogenic factors as TGF-β and CTGF on Kupffer cells. Differentially expressed genes in the microarray experiment indicated GHRP6 modulate the redox balance and parenchymal cells response to injury. These evidences suggest GHRP6 may control the liver's fibroplastic response. [ABSTRACT FROM AUTHOR]

Equine Infectious Anemia Virus (EIAV) is the causal agent of equine infectious anemia. Plasma virus RNA levels and the fraction of infected cells are both very low during the chronic stage of EIAV infections, turning the amplification of viral genes into a technically demanding task. In this work, DNA was extracted from the spleen of a chronically infected animal previously immunosuppressed with prednisolone, amplifying by nested PCR and sequencing the segment of the gag gene that codes for the p26 protein. Phylogenetic analysis placed the Cuban strain closest to three Canadian strains. The translated protein sequence exhibits 7 differences with the most related Canadian strain (Can7) and 13 with the Wyoming strain. This is the first report of a partial nucleotide sequence from EIAV in Cuba and the Caribbean. [ABSTRACT FROM AUTHOR]

Protein kinase CK2 has emerged as an attractive therapeutic target in acute myeloid leukemia (AML), an advent that becomes particularly relevant since the treatment of this hematological neoplasia remains challenging. Here we explored for the first time the effect of the clinical-grade peptide-based CK2 inhibitor CIGB-300 on AML cells proliferation and viability. CIGB-300 internalization and subcellular distribution were also studied, and the role of B23/nucleophosmin 1 (NPM1), a major target for the peptide in solid tumors, was addressed by knock-down in model cell lines. Finally, pull-down experiments and phosphoproteomic analysis were performed to study CIGB-interacting proteins and identify the array of CK2 substrates differentially modulated after treatment with the peptide. Importantly, CIGB-300 elicited a potent anti-proliferative and proapoptotic effect in AML cells, with more than 80% of peptide transduced cells within three minutes. Unlike solid tumor cells, NPM1 did not appear to be a major target for CIGB-300 in AML cells. However, in vivo pull-down experiments and phosphoproteomic analysis evidenced that CIGB-300 targeted the CK2α catalytic subunit, different ribosomal proteins, and inhibited the phosphorylation of a common CK2 substrates array among both AML backgrounds. Remarkably, our results not only provide cellular and molecular insights unveiling the complexity of the CIGB-300 anti-leukemic effect in AML cells but also reinforce the rationale behind the pharmacologic blockade of protein kinase CK2 for AML-targeted therapy. [ABSTRACT FROM AUTHOR]

CIGB-300 is an antitumor peptide that inhibits the CK2-mediated phosphorylation by direct targeting of substrates. This paper aims to describe breakthroughs about the CIGB-300 antineoplastic mechanism related to the inhibition of CK2-mediated phosphorylation and the synergism with anticancer drugs. CK2 phosphorylation assays were performed with catalytic CK2α subunit or the CK2 holoenzyme in presence or not of CIGB-300. CIGB-300/CK2 interaction was verified by pull-down experiments, in situ colocalization and phosphoproteomic analysis of CIGB-300-treated lung cancer cells were also performed. Synergism of the peptide with anticancer drugs was evaluated in vitro and for Cisplatin; it was also tested in vivo. Besides, comparative proteomics of CIGB-300 combined with Cisplatin was conducted. CIGB-300 targeted the CK2α subunit and inhi-bited the enzymatic activity of the holoenzyme in different experimental settings. Likewise, phosphoproteomic and Western Blot analysis allowed for knowing the early CK2 inhibition profile elicited by CIGB-300 at 10 and 30 min of treatment. Moreover, CIGB-300 did synergize with chemotherapeutics and EGFR inhibitors, and molecular events that reportedly support such synergistic interactions were also known. CIGB-300 inhibits the CK2-mediated phosphorylation by using an alternative mechanism of direct interaction with the enzyme itself. Besides, CIGB-300 synergizes with chemotherapeutics and EGFR inhibitors by modulating different proteins related to drug resistance. [ABSTRACT FROM AUTHOR]

In previous work, we identified the peptide comprising amino acids 32-51 on the antimicrobial protein limulus anti-LPS factor (LALF) from Limulus poliphemus, based on its capacity to bind to the bacterial lipopolysaccharide (LPS). In this study, we designed a chemical peptide library by alanine scanning from the sequence of the LALF32-51 peptide. Four new peptides, named L-2, L-8, L-12 and L-20 by the Ala residue substituted in the given position of the LALF32-51 peptide, were identified as retaining their penetrating activity but also showing antitumor effects when subcutaneously administered in female C57Bl/6 mice after the implantation of malignant TC-1 lung epithelial cells. They significantly increased animal survival (p < 0.05) as compared to LALF32-51. The substitution of Tyr residue to Ala at position 2 in the peptide sequence enhanced the cytotoxic effect, while residues Phe8, Lys12 and Trp20 were essential for the antitumor activity. Moreover, the administration of the L-2 peptide significantly reduced tumor growth in comparison to PBS- or L-20 peptide- treated lung TC-1 cells in C57Bl/6 mice. L-2 was found to deregulate the tumor cell cycle and induces apoptosis, through mechanisms affecting glycolytic and protein biosynthesis pathways. It also significantly increased survival in human colon cancer LS-174T xenotransplanted nude mice for up to 32 days, two of the animals being tumor free. The L-2 peptide could serve as peptide-based prototype drug with potential to reduce tumor load or could be coadministered with conventional chemotherapy. This research granted the 2013 Award of the Cuban National Academy of Sciences. [ABSTRACT FROM AUTHOR]