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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]

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]

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]

A prime-boost strategy combining FWPV (fowlpox virus) and the MVA (modified vaccinia virus Ankara), both expressing HIV-1 multi-V3 epitope polypeptides, was compared with a DNA-based Semliki Forest virus replicon/poxvirus approach for the induction of a CD8(+) T-cell response. Priming mice with recombinant MVA and boosting with recombinant FWPV, and not in the reverse order, increased the number of specific interferon-gamma-secreting cells in relation to the homologous combinations. Moreover, the improvement of the CD8(+) T-cell response with this combination was remarkably higher than that obtained by priming with a DNA vector containing a Semliki Forest virus replicon expressing the multi-epitope polypeptide and boosting either with recombinant MVA or FWPV. These results open a new and attractive alternative for vaccine preparation against HIV-1 using different immunogens.

Recombinant avipoxvirus vectors are attractive candidates for use in vaccination strategies for infections such as human immunodeficiency virus type 1 (HIV-1), where induction of a CD8+ T cell response is thought to be an important component of protective immunity. Here, we report the expression of a multiepitope polypeptide (TAB9) composed of the central 15 amino acids of the V3 loop from six different isolates of HIV-1 in a fowlpox virus (FWPV) vector, and the use of this vector (FPTAB9LZ) to induce strong HIV-specific CD8+ T cell responses in mice. In animals immunized twice intravenously with FPTAB9LZ, almost 2% of the CD8+ T cells in the spleen were shown to produce IFN-gamma in response to stimulation with HIV-1 peptides 1 week after the second immunization. The most dominant response was to the HIV-1 IIIB peptide. A strong HIV-specific response was also induced by intraperitoneal immunization of mice with FPTAB9LZ, whilst subcutaneous immunization elicited a weaker response. Intraperitoneal immunization with FPTAB9LZ was also shown to provide protection against challenge with a recombinant vaccinia virus expressing antigens, including those in TAB9. These results confirm the potential of FWPV vectors for use in HIV vaccination strategies.