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Three novel tetracationic bis-triarylboranes with 3, 4-ethylenedioxythiophene (EDOT) linkers, and their neutral precursors, showed significant red-shifted absorption and emission compared to their thiophene-containing analogues, with one of the EDOT-derivatives emitting in the NIR region. Only the EDOT-linked trixylylborane tetracation was stable in aqueous solution, indicating that direct attachment of a thiophene or even 3-methylthiophene to the boron atom is insufficient to provide hydrolytic stability in aqueous solution. Further comparative analysis of the EDOT-linked trixylylborane tetracation and its bis-thiophene analogue revealed efficient photo-induced singlet oxygen production, with the consequent biological implications. Thus, both analogues bind strongly to ds-DNA and BSA, very efficiently enter living human cells, accumulate in several different cytoplasmic organelles with no toxic effect but, under intense visible light irradiation, they exhibit almost instantaneous and very strong cytotoxic effects, presumably attributed to singlet oxygen production. Thus, both compounds are intriguing theranostic agents, whose intracellular and probably intra-tissue location can be monitored by strong fluorescence, allowing switching on of the strong bioactivity by well-focused visible light.

The low seroprevalent human adenovirus type 26 (HAdV26)-based vaccine vector was the first adenovirus-based vector to receive marketing authorization from European Commission. HAdV26-based vaccine vectors induce durable humoral and cellular immune responses and, as such, represent a highly valuable tool for fighting infectious diseases. Despite well-described immunogenicity in vivo, the basic biology of HAdV26 still needs some refinement. The aim of this study was to determine the pro-inflammatory cytokine profile of epithelial cells infected with HAdV26 and then investigate the underlying molecular mechanism. The expression of studied genes and proteins was assessed by quantitative polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay. Confocal microscopy was used to visualize HAdV26 cell uptake. We found that HAdV26 infection in human epithelial cells triggers the expression of pro-inflammatory cytokines and chemokines, namely IL-6, IL-8, IL-1β, and TNF-α, with the most pronounced difference shown for IL-6. We investigated the underlying molecular mechanism and observed that HAdV26-induced IL-6 gene expression is αvβ3 integrin dependent and NF-κB mediated. Our findings provide new data regarding pro-inflammatory cytokine and chemokine expression in HAdV26-infected epithelial cells, as well as details concerning HAdV26-induced host signaling pathways. Information obtained within this research increases our current knowledge of HAdV26 basic biology and, as such, can contribute to further development of HAdV26-based vaccine vectors.

A series of fluorescent mono- (1–4) and bis-pyrene derivatives (5–7) were synthesized and their photophysical and self-aggregation properties in solution were fully investigated by UV-vis and fluorescence spectroscopies and dynamic light scattering (DLS). While in dilute DMSO mono-pyrene derivatives 1–4 show the characteristic features of monomer emission, bis-pyrene derivatives 5–7 display both monomer and excimer emissions, the latter attributable to a dynamic process. The gelation behaviour of these compounds was also studied, and only mono-pyrene leucine derivative 1 was found to display efficient gelation in aromatic solvents, such as toluene and p-xylene, and in a polar solvent mixture, water/DMSO (4 : 1 v/v). Finally, mono-pyrenes 1–4 showed no apparent cytotoxic impact on A549 and RD cell lines ; derivatives 1–5 showed accumulation within both live and fixed cells, and macropinocytosis was found to be the main pathway for 5 to enter into the cells.

Oncolytic virotherapies (OV) hold immense clinical potential. OV based on human adenoviruses (HAdV) derived from HAdV with naturally low rates of pre- existing immunity will be beneficial for future clinical translation. We generated a low- seroprevalence HAdV-D10 serotype vector incorporating an αvβ6 integrin-selective peptide, A20, to target αvβ6-positive tumor cell types. HAdV-D10 has limited natural tropism. Structural and biological studies of HAdV-D10 knob protein highlighted low-affinity engagement with native adenoviral receptors CAR and sialic acid. HAdV-D10 fails to engage blood coagulation factor X, potentially eliminating “off-target” hepatic sequestration in vivo. We engineered an A20 peptide that selectively binds αvβ6 integrin into the DG loop of HAdV-D10 fiber knob. Assays in αvβ6+ cancer cell lines demonstrated significantly increased transduction mediated by αvβ6-targeted variants compared with controls, confirmed microscopically. HAdV-D10.A20 resisted neutralization by neutralizing HAdV-C5 sera. Systemic delivery of HAdV-D10.A20 resulted in significantly increased GFP expression in BT20 tumors. Replication-competent HAdV-D10.A20 demonstrated αvβ6 integrin-selective cell killing in vitro and in vivo. HAdV-D10 possesses characteristics of a promising virotherapy, combining low seroprevalence, weak receptor interactions, and reduced off-target uptake. Incorporation of an αvβ6 integrin-selective peptide resulted in HAdV-D10.A20, with significant potential for clinical translation.

Adenoviruses represent exceptional candidates for wide-ranging therapeutic applications, from vectors for gene therapy to oncolytics for cancer treatments. The first ever commercial gene therapy medicine was based on a recombinant adenovirus vector, while most recently, adenoviral vectors have proven critical as vaccine platforms in effectively controlling the global coronavirus pandemic. Here, we discuss factors involved in adenovirus cell binding, entry, and trafficking; how they influence efficiency of adenovirus-based vectors; and how they can be manipulated to enhance efficacy of genetically modified adenoviral variants. We focus particularly on endocytosis and how different adenovirus serotypes employ different endocytic pathways to gain cell entry, and thus, have different intracellular trafficking pathways that subsequently trigger different host antiviral responses. In the context of gene therapy, the final goal of the adenovirus vector is to efficiently deliver therapeutic transgenes into the target cell nucleus, thus allowing its functional expression. Aberrant or inefficient endocytosis can impede this goal, therefore, it should be considered when designing and constructing adenovirus-based vectors.

Aims Adenoviruses that have C NGR C VSG C AGR C peptide inserted into fiber (AdFNGR) or hexon (AdHNGR) protein, respectively, showed increased transduction of endothelial cells. In this study we investigated if cysteines within the C NGR C VSG C AGR C sequence inserted into Ad5 fiber or hexon protein form disulfide bond(s) and whether they play a role in retargeting potential of AdFNGR and AdHNGR. Methods Transduction efficiency of adenoviruses was done by counting infected cells under the microscope. Adenovirus attachment and internalization were measured by qPCR. Flow cytometry was used to evaluate the expression of CD13 and integrins. Gene knockdown was achieved by transfection of small interfering RNA. Mass spectrometry was used for determining disulfide bonds in adenovirus fiber and hexon protein. Molecular modeling was use to predict interaction of CNGRCVSGCAGRC peptide and CD13. Key findings AdFNGR and AdHNGR attach better to CD13 and/or αvβ3 integrin-positive cells than Adwt. Reducing disulfide bonds using DTT decreased transduction efficiency and attachment of both AdFNGR and AdHNGR. Cysteins from CNGRCVSGCAGRC peptide within AdHNGR do not form disulfide bonds. Knockdown of αvβ3 integrin reduced increased transduction efficiency of both AdFNGR and AdHNGR, while CD13 knockdown had no effect, indicating that retargeting properties of these viruses rely mainly on αvβ3 integrin expression. Significance Insertion site of NGR-containing peptides as well as NGR flanking residues are critical for receptor binding affinity/specificity and transduction efficiency of NGR retargeted adenoviral vectors.

We recently reported diethynylarene-linked bis(triarylborane) tetracations which show remarkable fluorimetric and Raman-SERS sensing of DNA/RNA. In the current study, we show that they exhibit promising photodynamic therapy (PDT)-based biological activity on human cell lines and adenovirus type 5 (HAdV5), acting as theranostic agents. All compounds efficiently enter living cells showing negligible antiproliferative activity. Bis-thiophene- and anthracene- analogues bind non-covalently to HAdV5 virus with high affinity, the anthracene-analogue itself causing a moderate antiviral effect, i.e., decreased ability of the virus to infect human cells. Irradiation of bis-thiophene- and anthracene- analogues with visible light (400-700 nm) caused a very rapid (within 1 minute) and strong increase in cytotoxicity, as well as an order of magnitude increase in antiviral activity, attributed to the formation of reactive oxygen species (ROS). Photochemical studies of the compounds revealed that, upon irradiation, they produce singlet oxygen, which correlates with the observed light-induced bioactivity.

Molybdenum trioxide (MoO3) nanoparticles (NPs) embedded in polymer films have been proposed as a cheap way of producing antibacterial coatings on external surfaces. Recently, we synthesized MoO3 nanowires in a unique shape and degree of anisotropy, which enables their fast water dissolution and quick antimicrobial reaction. Potential human health risks following the exposure to MoO3 NPs however need to be assessed prior their wide use. We therefore, investigated the biological effect of these newly synthesized MoO3 NPs on the human keratinocyte cell line HaCaT, used here as a model for the human skin. Exposure of HaCaT cells to 1 mg/mL MoO3 NPs concentration for 1 h showed no effect on cell survival, had no influence on reactive oxygen species production, expression of proteins involved in antioxidant defense, secretion of pro- inflammatory cytokines, nor induced DNA damage. Interestingly however, ERK and p38 MAP kinases were activated, and upon longer time exposure, induced a moderate release of the pro- inflammatory cytokine interleukin 6, increased DNA damage and increased the level of caspase independent cell death. Our study indicates that exposing HaCaT cells to antibacterial MoO3 NPs water-based solution in durations less than 1 h exhibits no cytotoxicity, but rather triggers cell signalling involved in cell survival and inflammation ; which should be taken into consideration when evaluating MoO3 NPs for medical applications.

Oncolytic virotherapies (OV) based on human adenoviral (HAdV) vectors hold significant promise for the treatment of advanced ovarian cancers where local, intraperitoneal delivery to tumour metastases is feasible, bypassing many complexities associated with intravascular delivery. The efficacy of HAdV-C5-based OV is hampered by a lack of tumour selectivity, where the primary receptor, hCAR, is commonly downregulated during malignant transformation. Conversely, folate receptor alpha (FRα) is highly expressed on ovarian cancer cells, providing a compelling target for tumour selective delivery of virotherapies. Here, we identify high-affinity FRα-binding oligopeptides for genetic incorporation into HAdV-C5 vectors. Biopanning identified a 12-mer linear peptide, DWSSWVYRDPQT, and two 7-mer cysteine-constrained peptides, CIGNSNTLC and CTVRTSAEC that bound FRα in the context of the phage particle. Synthesised lead peptide, CTVRTSAEC, bound specifically to FRα and could be competitively inhibited with folic acid. To assess the capacity of the elucidated FRα-binding oligopeptides to target OV to FRα, we genetically incorporated the peptides into the HAdV-C5 fiber-knob HI loop including in vectors genetically ablated for hCAR interactions. Unfortunately, the recombinant vectors failed to efficiently target transduction via FRα due to defective intracellular trafficking following entry via FRα, indicating that whilst the peptides identified may have potential for applications for targeted drug delivery, they require additional refinement for targeted virotherapy applications.

Integrins are heterodimeric glycoproteins that bind cells to extracellular matrix. Upon integrin clustering, multimolecular integrin adhesion complexes (IACs) are formed, creating links to the cell cytoskeleton. We have previously observed decreased cell migration and increased sensitivity to microtubule (MT) poisons, paclitaxel and vincristine, in the melanoma cell line MDA-MB-435S upon transfection with integrin alpha V specific siRNA, suggesting a link between adhesion and drug sensitivity. To elucidate the underlying mechanism, we determined alpha V-dependent changes in IAC composition. Using mass spectrometry (MS)-based proteomics, we analyzed the components of isolated IACs of MDA-MB-435S cells and two MDA-MB-435S-derived integrin alpha V specific shRNA-expressing cell clones with decreased expression of integrin alpha V. MS analysis showed that cells preferentially use integrin alpha V beta 5 for the formation of IACs. The differential analysis between MDA-MB-435S cells and clones with decreased expression of integrin alpha V identified key components of integrin alpha V beta 5 adhesion complexes as talins 1 and 2, alpha-actinins 1 and 4, filamins A and B, plectin and vinculin. The data also revealed decreased levels of several components of the cortical microtubule stabilization complex, which recruits MTs to adhesion sites (notably liprins alpha and beta, ELKS, LL5b, MACF1, KANK1, and KANK2), following alpha V knockdown. KANK2 knockdown in MDA-MB-435S cells mimicked the effect of integrin alpha V knockdown and resulted in increased sensitivity to MT poisons and decreased migration. Taken together, we conclude that KANK2 is a key molecule linking integrin alpha V beta 5 IACs to MTs, and enabling the actin-MT crosstalk that is important for both sensitivity to MT poisons and cell migration.

Introduction Integrins are heterodimeric glycoproteins that bind cells to extracellular matrix proteins. Upon integrin clustering, multimolecular integrin adhesion complexes (IACs) form that facilitate the linkage between integrins and the actin cytoskeleton and permit bidirectional signalling. The αV integrin is expressed in most tumour cells where it regulates an array of cellular functions and plays a role in anti-tumour drug resistance. The aim of our work was to assess αV-dependent changes in IAC composition in MDA-MB-435S melanoma cells in order to better understand the increased sensitivity to paclitaxel and vincristine upon integrin αV knockdown. Material and methods Integrin αV-specific shRNA was cloned into pSUPER.puro, transfected into MDA-MB-435S cells using Lipofectamine, and cell clones were selected using puromycin. The sensitivity of cells to antitumor drugs was determined using an MTT assay. Cell migration was monitored using a Transwell assay. IACs were isolated following crosslinking and their molecular composition analysed using mass spectrometry (MS)–based proteomics. Results and discussions In two MDA-MB-435S-derived cell clones with decreased expression of integrin αV, expressing 15% (2αV) or 5% (3αV) of the control cells amount, increased sensitivity to paclitaxel and vincristine, decreased sensitivity to cisplatin, and decreased migration were observed in line with previous results obtained following transient transfection with integrin αV siRNA. In cell clones 2αV and 3αV, which were smaller than control cells and lacked stress fibres, the number of focal adhesions was shown to be significantly lower as observed by interference reflection microscopy and immunofluorescence detection of phospho-paxillin, phospho-FAK and phospho-Src. MS analysis of isolated IACs from control MDA-MB-435S, 2αV and 3αV cells identified 282 proteins, including 36 out of 60 consensus adhesome proteins. As expected, in clones 2αV and 3αV, integrins αV, β3 and β5 were detected at much lower levels compared with control cells. In addition, lower levels of talin-1 and −2, vinculin, alpha-actinin-4, tensin-3, filamin-A and -B, liprin β1 and plectin were detected. Conclusion These data will enable follow-up analyses of the mechanisms of signalling by integrins αVβ3/β5 and therefore represent a valuable resource to improve our understanding of the mechanisms involved in adhesion control of cell sensitivity to antitumor drugs and metastatic potential.

Bioethanol production from raw lignocelullosic material requires a strain of a microorganism which tolerates high ethanol concentrations and presence of growth inhibitors. Therefore we constructed hybrid diploid S.cerevisiae strains by mating two haploids having desirable traits. One haploid was isolated from wine thus tolerating high ethanol concentration and the other has been shown to be resistant to several growth inhibitors. These haploids were mated and resulting homozygous and heterozygous (hybrid) diploids were tested for the ability to produce ethanol and to grow in the presence of several growth inhibitors frequently found in different lignocelullosic hydrolysates (acetic and levulinic acid, 2-furaldehyde). The results showed that some hybrid diploids were more resistant to tested inhibitors than parental haploid strains and homozygous diploids. It is also interesting that constructed strains showed different fermentation ability in CO2 production test, suggesting genetic variability of constructed hybrids. All together, these results suggest that the approach used in this study may help to construct new strains as well as to improve traits of biotechnologically interesting strains.