Synthetic biological circuits are designed to regulate gene expressions to control cell function. To date, these circuits often use DNA-delivery methods, which may lead to random genomic integration. ...To lower this risk, an all RNA system, in which the circuit and delivery method are constituted of RNA components, is preferred. However, the construction of complexed circuits using RNA-delivered devices in living cells has remained a challenge. Here we show synthetic mRNA-delivered circuits with RNA-binding proteins for logic computation in mammalian cells. We create a set of logic circuits (AND, OR, NAND, NOR, and XOR gates) using microRNA (miRNA)- and protein-responsive mRNAs as decision-making controllers that are used to express transgenes in response to intracellular inputs. Importantly, we demonstrate that an apoptosis-regulatory AND gate that senses two miRNAs can selectively eliminate target cells. Thus, our synthetic RNA circuits with logic operation could provide a powerful tool for future therapeutic applications.
Most patients with non‐small cell lung cancer (NSCLC) harboring common epidermal growth factor receptor (EGFR) mutations, such as deletions in exon 19 or the L858R mutation in exon 21, respond ...dramatically to EGFR tyrosine kinase inhibitors (EGFR‐TKI), and their sensitivities to various EGFR‐TKI have been well characterized. Our previous article showed the in vitro sensitivities of EGFR exon 18 mutations to EGFR‐TKI, but little information regarding the sensitivities of other uncommon EGFR mutations is available. First, stable transfectant Ba/F3 cell lines harboring EGFR L858R (Ba/F3‐L858R), L861Q (Ba/F3‐L861Q) or S768I (Ba/F3‐S768I) mutations were created and their drug sensitivities to various EGFR‐TKI were examined. Both the Ba/F3‐L861Q and Ba/F3‐S768I cell lines were less sensitive to erlotinib, compared with the Ba/F3‐L858R cell line, but their sensitivities to afatinib were similar to that of the Ba/F3‐L858R cell line. The Ba/F3‐L861Q cell line was similarly sensitive and the Ba/F3‐S768I cell line was less sensitive to osimertinib, compared with the Ba/F3‐L858R cell line. The results of western blot analyses were consistent with these sensitivities. Next, similar experiments were also performed using the KYSE270 (L861Q) and KYSE 450 (S768I) cell lines, and their results were compatible with those of the transfectant Ba/F3 cell lines. Our findings suggest that NSCLC harboring the EGFR L861Q mutation might be sensitive to afatinib or osimertinib and that NSCLC harboring the EGFR S768I mutation might be sensitive to afatinib. Overall, afatinib might be the optimal EGFR‐TKI against these uncommon EGFR mutations.
In this study, we focused on the EGFR L861Q and S768I mutations and investigated the in vitro sensitivities of cells carrying these mutations to various EGFR‐tyrosine kinase inhibitors (TKIs). Non‐small cell lung cancer (NSCLC) harboring the EGFR L861Q mutation might be sensitive to afatinib or osimertinib but not to erlotinib, and NSCLC harboring the EGFR S768I mutation might be sensitive to afatinib but not to erlotinib or osimertinib. Afatinib might be the optimal EGFR‐TKI against these uncommon EGFR mutations.
The original version of this Article contained an error in the fourth sentence of the second paragraph of the 'Improving the performance of miRNA-responsive circuits' section of the Results, which ...incorrectly read 'We confirmed a significant fold-change between ON and OFF states (from 3.5- to 9.0-fold) in 293FT cells (Supplementary Figure 3).' The correct version states '4.6' in place of '3.5'. This has been corrected in both the PDF and HTML versions of the Article.The original version of the Supplementary Information contained a corresponding error in Supplementary Figure 3. The HTML has been updated to include a corrected version of the Supplementary Information.
RNA-based gene circuits for cell regulation KARAGIANNIS, Peter; FUJITA, Yoshihiko; SAITO, Hirohide
Proceedings of the Japan Academy, Series B,
2016, Letnik:
92, Številka:
9
Journal Article
Recenzirano
Odprti dostop
A major goal of synthetic biology is to control cell behavior. RNA-mediated genetic switches (RNA switches) are devices that serve this purpose, as they can control gene expressions in response to ...input signals. In general, RNA switches consist of two domains: an aptamer domain, which binds to an input molecule, and an actuator domain, which controls the gene expression. An input binding to the aptamer can cause the actuator to alter the RNA structure, thus changing access to translation machinery. The assembly of multiple RNA switches has led to complex gene circuits for cell therapies, including the selective killing of pathological cells and purification of cell populations. The inclusion of RNA binding proteins, such as L7Ae, increases the repertoire and precision of the circuit. In this short review, we discuss synthetic RNA switches for gene regulation and their potential therapeutic applications.
A secondary epidermal growth factor receptor (EGFR) mutation, the substitution of threonine 790 with methionine (T790M), leads to acquired resistance to reversible EGFR‐tyrosine kinase inhibitors ...(EGFR‐TKIs). A non‐invasive method for detecting T790M mutation would be desirable to direct patient treatment strategy. Plasma DNA samples were obtained after discontinuation of gefitinib or erlotinib in 75 patients with non‐small cell lung cancer (NSCLC). T790M mutation was amplified using the SABER (single allele base extension reaction) technique and analyzed using the Sequenom MassARRAY platform. We examined the T790M mutation status in plasma samples obtained after treatment with an EGFR‐TKI. The SABER assay sensitivity using mixed oligonucleotides was determined to be 0.3%. The T790M mutation was detected in 21 of the 75 plasma samples (28%). The presence of the T790M mutation was confirmed by subcloning into sequencing vectors and sequencing in 14 of the 21 samples (66.6%). In this cohort of 75 patients, the median progression‐free survival (PFS) of the patients with the T790M mutation (n = 21) was not statistically different from that of the patients without the mutation (n = 54, P = 0.94). When patients under 65 years of age who had a partial response were grouped according to their plasma T790M mutation status, the PFS of the T790M‐positive patients (n = 11) was significantly shorter than that of the T790M‐negative patients (n = 29, P = 0.03). The SABER method is a feasible means of determining the plasma T790M mutation status and could potentially be used to monitor EGFR‐TKI therapy.
The regulation of cell signaling pathways and the reconstruction of genetic circuits are important aspects of bioengineering research. Both of these goals require molecular devices to transmit ...information from an input biomacromolecule to the desired outputs. Here, we show that an RNA-protein (RNP)-containing L7Ae-kink-turn interaction can be used to construct translational regulators under control of an input protein that regulates the expression of desired output proteins. We built a system in which L7Ae, an archaeal ribosomal protein, regulates the translation of a designed mRNA in vitro and in human cells. The translational regulator composed of the RNP might provide new therapeutic strategies based on the detection, repair or rewiring of intrinsic cellular defects, and it may also serve as an invaluable tool for the dissection of the behavior of complex, higher-order circuits in the cell.
Purpose: In this study, our purpose was to examine the relationship between skeletal muscle mass and higher-level functional capacity in female community-dwelling older adults. Participant(s) and ...Methods: In this cross-sectional study, we targeted 55 female community-dwelling older adults aged 65 years and above participating in long-term care prevention classes in Ibaraki Prefecture between 2018 and 2020. We excluded individuals with cognitive impairment and those judged as having sarcopenia. The variables of interest included age, height, weight, body mass index, skeletal muscle mass index (SMI), handgrip strength, step count, and family structure. We calculated the SMI by dividing the extremities’ total lean mass by the square of the height (in m), while the number of steps was calculated using the three-axis accelerometer Actigraph GT3X®. We measured skeletal muscle mass via bioelectrical impedance analysis using the InBody270 body composition analyzer and muscular strength as grip strength. Results: We observed significant relationships between skeletal muscle mass and Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) (β = 0.336, p < 0.01) and handgrip strength (β = 0.230). Conclusion: In this study, a relationship between skeletal muscle mass and higher-level functional capacity was demonstrated among elderly female community residents.
Fibroblast growth factor receptor (FGFR) gene alterations are relatively frequent in lung squamous cell carcinoma (LSCC) and are a potential targets for therapy with FGFR inhibitors. However, little ...is known regarding the clinicopathologic features associated with FGFR alterations. The angiokinase inhibitor nintedanib has shown promising activity in clinical trials for non‐small cell lung cancer. We have now applied next‐generation sequencing (NGS) to characterize FGFR alterations in LSCC patients as well as examined the antitumor activity of nintedanib in LSCC cell lines positive for FGFR1 copy number gain (CNG). The effects of nintedanib on the proliferation of and FGFR signaling in LSCC cell lines were examined in vitro, and its effects on tumor formation were examined in vivo. A total of 75 clinical LSCC specimens were screened for FGFR alterations by NGS. Nintedanib inhibited the proliferation of FGFR1 CNG‐positive LSCC cell lines in association with attenuation of the FGFR1–ERK signaling pathway in vitro and in vivo. FGFR1 CNG (10.7%), FGFR1 mutation (2.7%), FGFR2 mutation (2.7%), FGFR4 mutation (5.3%), and FGFR3 fusion (1.3%) were detected in LSCC specimens by NGS. Clinicopathologic features did not differ between LSCC patients positive or negative for FGFR alterations. However, among the 36 patients with disease recurrence after surgery, prognosis was significantly worse for those harboring FGFR alterations. Screening for FGFR alterations by NGS warrants further study as a means to identify patients with LSCC recurrence after surgery who might benefit from nintedanib therapy.
The angiokinase inhibitor nintedanib is a potential targeted agent for lung squamous cell carcinoma (LSCC) positive for genetic alterations affecting FGFR genes. We screened 75 LSCC specimens for FGFR alterations by next‐generation sequencing and thereby identified various such genetic changes including copy number gain, mutations, and a fusion in 15 of the 75 (20.0%) cases. Among the patients with relapse after surgery, the presence of FGFR alterations was associated with a significantly shorter overall survival.
Highlights • The plasma activin A level can be a prognostic factor in patents with advanced pancreatic cancer (PC). • The activin signal promotes cancer progression via non-SMAD pathways in a subset ...of PC and might be involved in cachexia. • The activin signal might be a novel target for the treatment of PC.
Abstract
Background
We hypothesized that the high-dose opioid requirement in patients carrying the rs4680-GG variant in the COMT gene encoding catechol-O-methyltransferase would be greater for ...patients taking morphine than for those taking oxycodone, thus providing a much-needed biomarker to inform opioid selection for cancer pain.
Methods
A randomized, multicenter, open-label trial was conducted at a Japanese hospital’s palliative care service. Patients with cancer pain treated with regular doses of nonsteroidal anti-inflammatory drugs or acetaminophen were enrolled and randomized (1:1) into morphine (group M) and oxycodone (group O) groups. The minimum standard dose of immediate-release (IR) oral opioids was repeatedly administered by palliative care physicians to achieve pain-reduction goals (Pain reduction ≥ 33% from baseline and up to ≤ 3 on a numerical rating scale). The primary endpoint was the proportion of subjects requiring high-dose opioids on day 0 with the GG genotype.
Results
Of 140 participants who developed cancer-related pain among 378 subjects registered and pre-screened for the genotype, 139 were evaluated in the current study. Among patients carrying a COMT rs4680-GG genotype, 48.3% required high-dose opioids in group M, compared with the 20.0% in group O (95% CI, 3.7%-50.8%; P = .029). Of those with the non-GG genotype, 41.5% treated with morphine and 23.1% with oxycodone required high-dose opioids (95% CI, 3.3%-38.3%; P = 0.098).
Conclusion
Using the COMT rs4680 genotype alone is not recommended for selecting between morphine and oxycodone for pain relief.
This report evaluates the potential for the COMT rs4680 genotype to serve as a biomarker for opioid choice.
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