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PL
W ciągu ostatnich lat zjawisko interferencji RNA (RNAi) stało się powszechnie wykorzystywane jako eksperymentalne narządzie do analizy genów oraz pełnionych przez nie funkcji. Wraz ze wzrostem wiedzy na temat molekularnych mechanizmów działania endogennego interferującego RNA, małe interferujące RNA (siRNA), mogą pojawić się jako grupa innowacyjnych bioleków stosowanych do leczenia wielu chorób m.in. chorób nowotworowych. Poznanie i zrozumienie szlaków molekularnych istotnych w procesie nowotworzenia stwarza możliwości dla terapii nowotworowej wykorzystującej mechanizm RNAi. Nowe terapie w leczeniu nowotworów są niezbędne, a wykorzystanie małych interferujących RNA może stanowić realną strategię.
EN
In the last few years, RNA interference (RNAi) has become widely used as an experimental tool for the analyses of genes and their functions. With increasing knowledge about the molecular mechanisms of function of endogenous RNA interference, small interfering RNA (siRNA), may occur as innovative bio-drugs for treatment of diseases such as cancer. Knowledge and understanding of the molecular pathways important for carcinogenesis create opportunities for cancer therapy using RNAi mechanism. New therapies are essential for tumors treatment, and small interfering RNAs may provide a viable strategy.
EN
Polyglutamine (polyQ) diseases comprise a group of nine genetic disorders that are caused by the expansion of the CAG triplet repeat, which encodes glutamine, in unrelated single genes. Various oligonucleotide (ON)-based therapeutic approaches have been considered for polyQ diseases. The very attractive CAG repeat-targeting strategy offers selective silencing of the mutant allele by directly targeting the mutation site. CAG repeat-targeting miRNA-like siRNAs have been shown to specifically inhibit the mutant gene expression, and their characteristic feature is the formation of mismatches in their interactions with the target site. Here, we designed novel single-stranded siRNAs that contain base substitutions and chemical modifications, in order to develop improved therapeutic tools with universal properties for several polyQ diseases. We tested these ONs in cellular models of Huntington's disease (HD), spinocerebellar ataxia type 3 (SCA3) and dentatorubral-pallidoluysian atrophy (DRPLA). Selected siRNAs caused the efficient and selective downregulation of the mutant huntingtin, ataxin-3 and atrophin-1 levels in cultured human fibroblasts. We also prove the efficiency of novel ONs, with chemical modification pattern mainly containing 2'-fluoro (2'F), in HD mouse striatal cells.
EN
Cytotoxicity of laronidase (Aldurazyme®), employed in enzyme replacement therapy (ERT) for mucopolysaccharidosis type I (MPS I) and various siRNAs, tested previously in studies on substrate reduction therapy (SRT) for mucopolysaccharidoses, was tested. The enzyme did not cause any cytotoxic effects, and the siRNAs did not inhibit growth of most investigated cell lines. However, some cytotoxic effects of some tested siRNAs were observed in one MPS IIIA cell line. The efficacy of a combination of enzyme replacement therapy and siRNA-based substrate deprivation therapy was tested on three MPS I cell lines. Surprisingly, different results were obtained for different cell lines. The decrease of glycosaminoglycan storage in cells treated simultaneously with both methods was: (i) less pronounced than obtained with either of those methods used alone in one cell line, (ii) similar to that observed for enzyme replacement therapy in another cell line, and (iii) stronger than that obtained with either of the methods used alone in the third cell line. Therefore, it appears that the effects of various therapeutic methods may strongly depend on the features of the MPS cell line.
EN
In our earlier studies of the signaling cross-talk between nucleotide receptors in an in vitro glioma model (C6 cell line) under prolonged serum deprivation conditions, a growth arrest of the cells and expression shift from P2Y1 to P2Y12 receptors was found. The aim of the present work was to test if siRNA silencing of P2Y1 receptor changes P2Y12 expression similarly as following the serum deprivation and which physiological downstream pathways it affects. Here we demonstrate for the first time the efficiency of siRNA technology in silencing P2Y nucleotide receptors in glioma C6 cell line. Moreover, P2Y12 proved to be insensitive to the P2Y1 receptor silencing. The effect of the P2Y1 silencing on calcium signaling was less pronounced then the extent of the protein change itself, exactly as was the case for the serum starvation experiments. Phosphorylation of ERK and Akt kinases were studied as the downstream effect of P2Y1-evoked signaling and similar effects as in the case of serum deprivation were found for ERK, and even stronger ones for Akt phosphorylation.
PL
Glejak wielopostaciowy klasyfikowany jest do grupy najbardziej złośliwych glejaków o IV stopniu złośliwości ze szczególnie niekorzystnymi prognozami związanymi z jego leczeniem. Pojawienie się u pacjenta szybko postępujących objawów zarówno psychiatrycznych, jak i neurologicznych powinno być zawsze dokładnie zbadane. Artykuł ma na celu zebranie oraz podsumowanie aktualnej wiedzy na temat glejaka oraz zaprezentowanie możliwych perspektyw rozwoju metod diagnostyczno-leczniczych. Rozwój glejaka ma zazwyczaj związek z mutacjami w genach EGFR, PTEN, IDH1 lub p53. Do użytecznych narzędzi diagnostycznych należą m.in. badanie MRI, analiza metylacji promotora genu MGMT oraz immunohistochemiczne oznacznie GFAP. W leczeniu glejaków wielopostaciowych najczęściej stosowanym schematem jest protokół Stuppa bazujący na połączeniu radioterapii z chemioterapią temozolomidem. Niemniej jednak, dalsze możliwości leczenia są limitowane. Zintegrowane wysiłki naukowców są ukierunkowane na poszukiwanie nowych strategii leczenia przy użyciu m.in. teraapii CAR-T, nanocząteczek, przeciwciał monoklonalnych, miRNA, siRNA oraz inhibitorów proteasomów
EN
Glioblastoma is the most severe IV-class glioma and therefore the prognosis for patients remains poor despite some improvement in the treatment area. The neurological or psychiatric symptoms especially fast-developing ones should be fully investigated. This article aims to summarize actual knowledge of glioblastoma and present future perspectives. The underlying causes are usually associated with mutations of EGFR, PTEN, IDH1, p53 genes. The MRI scan, MGMT promoter methylation status, GFAP immunohistochemical detection and Karnofsky performance status are valuable diagnostic tools and some other potential biomarkers with high specificity are proposed. The standard of care is surgery and Stupp protocol which is the combination of radiotherapy and chemotherapy with temozolomide. Nevertheless, after remission the treatment possibilities are limited. Many efforts have been devoted to elaborate novel therapeutic strategies using e.g. CAR-T cells, nanoparticles, monoclonal antibodies, miRNA, siRNA or proteasome inhibitors.
EN
The involvement of the clathrin-mediated endocytic internalization route in the uptake of cholera toxin (CT) was investigated using different cell lines, including the human intestinal Caco-2 and T84 cell lines, green monkey Vero cells, SH-SY5Y neuroblastoma cells and Madin-Darby canine kidney cells. Suppression of the clathrin-mediated endocytic pathway by classical biochemical procedures, like intracellular acidification and potassium depletion, inhibited cholera toxin uptake by up to about 50% as well as its ability to raise intracellular levels of cAMP. Also prior exposure of these cell types to the cationic amphiphilic drug chlorpromazine reduced the functional uptake of cholera toxin, even to a greater extent. These effects were dose- and cell type-dependent, suggesting an involvement of clathrin-mediated endocytosis in the functional uptake of cholera toxin. For a more straightforward approach to study the role of the clathrin-mediated uptake in the internalization of cholera toxin, a Caco-2eps- cell line was exploited. These Caco-2eps- cells constitutively suppress the expression of epsin, an essential accessory protein of clathrin-mediated endocytosis, thereby selectively blocking this internalization route. CT uptake was found to be reduced by over 60% in Caco-2eps- paralleled by a diminished ability of CT to raise the level of cAMP. The data presented suggest that the clathrin-mediated uptake route fulfils an important role in the functional internalization of cholera toxin in several cell types.
EN
Therapies based on RNA interference (RNAi) hold a great potential for targeted interference of the expression of specific genes. Small-interfering RNAs (siRNA) and micro-RNAs interrupt protein synthesis by inducing the degradation of messenger RNAs or by blocking their translation. RNAibased therapies can modulate the expression of otherwise undruggable target proteins. Full exploitation of RNAi for medical purposes depends on efficient and safe methods for delivery of small RNAs to the target cells. Tremendous effort has gone into the development of synthetic carriers to meet all requirements for efficient delivery of nucleic acids into particular tissues. Recently, exosomes unveiled their function as a natural communication system which can be utilized for the transport of small RNAs into target cells. In this review, the capabilities of exosomes as delivery vehicles for small RNAs are compared to synthetic carrier systems. The step by step requirements for efficient transfection are considered: production of the vehicle, RNA loading, protection against degradation, lack of immunogenicity, targeting possibilities, cellular uptake, cytotoxicity, RNA release into the cytoplasm and gene silencing efficiency. An exosomebased siRNA delivery system shows many advantages over conventional transfection agents, however, some crucial issues need further optimization before broad clinical application can be realized.
PL
Auksyna wpływa na większość procesów wzrostu i rozwoju roślin. Szlak transdukcji sygnału auksyn tworzony jest przez komponenty białkowe, z których kluczowe są: receptory z rodziny TAAR (TIR1 oraz AFB1-3), represory odpowiedzi na auksynę AUX/IAA i czynniki transkrypcyjne AUXIN RESPONSE FACTOR (ARF). Aktywność genów kodujących niektóre elementy tego szlaku jest regulowana przez niskocząsteczkowe regulatorowe RNA, miRNA (micro RNA), i siRNA (short-interfering RNA), endogenne, niekodujące małe RNA (small RNA, sRNA) o długości 20-25 nukleotydów, różniące się sposobem powstawania (prekursorowymi molekułami i szlakami syntezy) oraz funkcją. Sekwencje TIR1 i AFB1-3 zawierają miejsce docelowe dla miR393 i drugorzędowe dla siTAAR. Transkrypt genu IAA28 jest celem dla miR847. Ekspresja genów: ARF10, ARF16 i ARF17 podlega bezpośredniej kontroli przez miR160, ARF6 i ARF8 przez miR167, natomiast ekspresja ARF2-4 podlega regulacji przez miR390 za pośrednictwem ta-siRNA pochodzącego z locus TAS3. sRNA wpływają przede wszystkim na lokalizację tkankową i czasową opisanych elementów szlaku auksynowego.
EN
Auxin affects almost all of the growth and development processes in plants. The auxin signal transduction pathway involves a number of proteins, among which the key elements are: TAAR auxin receptors (TIR1 and AFB1-3), AUX/IAA auxin response repressors and Auxin Response Factor (ARF) transcription factors. The activity of genes encoding some components of this pathway is affected by regulatory low-molecular-weight RNAs - miRNA (micro RNA) and siRNA (short-interfering RNA) - endogenous non-coding 20-25 nucleotides long small RNA (sRNA), differing in the way of formation (precursor molecules and biosynthesis pathways) and function. TIR1 and AFB1-3 contain miR393 target sequence and siTAAR secondary target site. IAA28 transcripts are targeted by miR847. Expression of ARF10, ARF16 i ARF17 is directly controlled by miR160, ARF6 and ARF8 by miR167, and ARF2-4 indirectly by miR390 through TAS3-derived ta-siRNAs. sRNAs influence primarily the tissue and temporal localization of described components of the auxin signal transduction pathway.
EN
Proteins are considered to be the key players in structure, function, and metabolic regulation of our bodies. The mechanisms used in conventional therapies often rely on inhibition of proteins with small molecules, but another promising method to treat disease is by targeting the corresponding mRNAs. In 1998, Craig Mellow and Andrew Fire discovered dsRNA-mediated gene silencing via RNA interference or RNAi. This discovery introduced almost unlimited possibilities for new gene silencing methods, thus opening new doors to clinical medicine. RNAi is a biological process that inhibits gene expression by targeting the mRNA. RNAi-based therapeutics have several potential advantages (i) a priori ability to target any gene, (ii) relatively simple design process, (iii) sitespecificity, (iv) potency, and (v) a potentially safe and selective knockdown of the targeted cells. However, the problem lies within the formulation and delivery of RNAi therapeutics including rapid excretion, instability in the bloodstream, poor cellular uptake, and inefficient intracellular release. In an attempt to solve these issues, different types of RNAi therapeutic delivery strategies including multifunctional RNA nanoparticles are being developed. In this mini-review, we will briefly describe some of the current approaches.
EN
Osteosarcoma is the most common primary malignant bone tumor in adolescents and young adults. However, the involvement of serine/threonine phosphatase type 5 (PP5) in osteosarcoma remains unclear. The aim of this study was to evaluate the functional role of PP5 in osteosarcoma cells. Firstly, we found that PP5 is widely expressed in several human osteosarcoma cell lines. Then we used lentivirus-delivered siRNA to silence PP5 expression in Saos-2 and U2OS cell lines. Knockdown of endogenous PP5 expression by shRNA-expressing lentivirus significantly decreased the viability and proliferation of the osteosarcoma cells. Moreover, FACS analysis showed that knockdown of PP5 expression induced a significant arrest in the G0/G1 phase of the cell cycle, which was associated with the inhibition of cell proliferation. Therefore, knockdown of PP5 is likely to provide a novel alternative to targeted therapy of osteosarcoma and deserves further investigation.
EN
According to statistics, ovarian cancer is the fourth cause of death due to gynecologic cancer. It results from late diagnosis of the disease, caused by the lack of characteristic symptoms, as well as from unsatisfactory treatment methods due to e.g. cell resistance to chemotherapy. The search for new therapies is still in progress. It is believed that preparations whose activity is based on RNA interference, i.e. gene silencing with the use of siRNA, are a promising group of new antineoplastic medications. Fire et al. were awarded the Nobel Prize for discovering this phenomenon. The phenomenon of siRNA interference in healthy cells is a natural protective mechanism. Genes are silenced in the cytoplasm with the use of the Dicer enzyme. siRNA gene preparations are delivered into cells with the use of viral methods such as AAV or adenoviruses, as well as non-viral methods e.g. with the use of liposomes. Clinical trials concerning siRNA preparations are now in the first phase. They are conducted on two gene preparations: CALAA-01 and siRNA nanomolecule directed against PLK1. In this paper attention was drawn to the therapeutic meaning of siRNA sequences in relation to the following genes: MDR1, VEGF, MMP, CD44, HER2, SHH, STAT. Both experimental and clinical studies give hope for the use of the described mechanisms in fight with ovarian cancer in the future.
PL
Rak jajnika według statystyk zajmuje czwarte miejsce wśród zgonów z powodu nowotworów ginekologicznych. Wynika to zarówno z późnego rozpoznania choroby, spowodowanego brakiem charakterystycznych objawów, jak i stale niezadowalających efektów leczenia, m.in. ze względu na oporność komórek na chemioterapię. Poszukiwanie nowych metod terapii jest więc nadal aktualne. Uważa się, że obiecującą grupą potencjalnych leków przeciwnowotworowych mogą być preparaty, których aktywność opiera się na zjawisku interferencji RNA, czyli wyciszaniu genów za pomocą siRNA. Za odkrycie tego zjawiska Fire i wsp. zostali uhonorowani Nagrodą Nobla. Zjawisko interferencji siRNA w prawidłowych komórkach jest naturalnym mechanizmem obronnym. Do wyciszenia genów dochodzi w cytoplazmie przy udziale enzymu Dicer. Preparaty genowe siRNA wprowadza się do komórek, wykorzystując metody wirusowe, takie jak AAV czy adenowirusy, a także za pomocą metod niewirusowych, np. z zastosowaniem liposomów. Badania kliniczne preparatów genowych siRNA znajdują się obecnie w pierwszej fazie. Prowadzone są na dwóch preparatach genowych CALAA-01 oraz na nanocząsteczce siRNA skierowanej przeciw PLK1. W niniejszej pracy skupiono uwagę na terapeutycznym znaczeniu sekwencji siRNA w stosunku do genów: MDR1, VEGF, MMP, CD44, HER2, SHH, STAT. Zarówno badania eksperymentalne, jak i kliniczne niosą nadzieję na wykorzystanie w przyszłości omawianego mechanizmu do walki z rakiem jajnika.
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