Real-time field-programmable gate array-based closed-loop deep brain stimulation platform targeting cerebellar circuitry rescues motor deficits in a mouse model of cerebellar ataxia.

AIMS: The open-loop nature of conventional deep brain stimulation (DBS) produces continuous and excessive stimulation to patients which contributes largely to increased prevalence of adverse side effects. Cerebellar ataxia is characterized by abnormal Purkinje cells (PCs) dendritic arborization, loss of PCs and motor coordination, and muscle weakness with no effective treatment. We aim to develop a real-time field-programmable gate array (FPGA) prototype targeting the deep cerebellar nuclei (DCN) to close the loop for ataxia using conditional double knockout mice with deletion of PC-specific LIM homeobox (Lhx)1 and Lhx5, resulting in abnormal dendritic arborization and motor deficits. METHODS: We implanted multielectrode array in the DCN and muscles of ataxia mice. The beneficial effect of open-loop DCN-DBS or closed-loop DCN-DBS was compared by motor behavioral assessments, electromyography (EMG), and neural activities (neurospike and electroencephalogram) in freely moving mice. FPGA board, which performed complex real-time computation, was used for closed-loop DCN-DBS system. RESULTS: Closed-loop DCN-DBS was triggered only when symptomatic muscle EMG was detected in a real-time manner, which restored motor activities, electroencephalogram activities and neurospike properties completely in ataxia mice. Closed-loop DCN-DBS was more effective than an open-loop paradigm as it reduced the frequency of DBS. CONCLUSION: Our real-time FPGA-based DCN-DBS system could be a potential clinical strategy for alleviating cerebellar ataxia and other movement disorders.

Effective and efficient neural networks for spike inference from in vivo calcium imaging.

Calcium imaging provides advantages in monitoring large populations of neuronal activities simultaneously. However, it lacks the signal quality provided by neural spike recording in traditional electrophysiology. To address this issue, we developed a supervised data-driven approach to extract spike information from calcium signals. We propose the ENS2 (effective and efficient neural networks for spike inference from calcium signals) system for spike-rate and spike-event predictions using ΔF/F0 calcium inputs based on a U-Net deep neural network. When testing on a large, ground-truth public database, it consistently outperformed state-of-the-art algorithms in both spike-rate and spike-event predictions with reduced computational load. We further demonstrated that ENS2 can be applied to analyses of orientation selectivity in primary visual cortex neurons. We conclude that it would be a versatile inference system that may benefit diverse neuroscience studies.

Positive feedback of efferent copy via pontine nucleus facilitates cerebellum-mediated associative learning.

The cerebellum is critical for motor coordination and learning. However, the role of feedback circuitry in this brain region has not been fully explored. Here, we characterize a nucleo-ponto-cortical feedback pathway in classical delayed eyeblink conditioning (dEBC) of rats. We find that the efference copy is conveyed from the interposed cerebellar nucleus (Int) to cerebellar cortex through pontine nucleus (PN). Inhibiting or exciting the projection from the Int to the PN can decelerate or speed up acquisition of dEBC, respectively. Importantly, we identify two subpopulations of PN neurons (PN1 and PN2) that convey and integrate the feedback signals with feedforward sensory signals. We also show that the feedforward and feedback pathways via different types of PN neurons contribute to the plastic changes and cooperate synergistically to the learning of dEBC. Our results suggest that this excitatory nucleo-ponto-cortical feedback plays a significant role in modulating associative motor learning in cerebellum.

Docetaxel, Cisplatin, and 5-FU Triplet Therapy as Conversion Therapy for Locoregionally Advanced Unresectable Esophageal Squamous Cell Carcinoma.

BACKGROUND: The standard treatment for locoregionally advanced unresectable esophageal squamous cell carcinoma was radical chemoradiotherapy. However, the prognosis was modest. Emerging evidence showed the concept of induction chemotherapy with a goal of conversion surgery. METHODS: We reviewed the long-term, clinical outcomes and safety data of induction chemotherapy using docetaxel-cisplatin-5FU (DCF) and subsequent definitive treatment, either surgery or radical chemoradiotherapy (CRT), in locally advanced unresectable esophageal cancer in Queen Mary Hospital, Hong Kong. A total of 47 patients (median age 62 years, male: 41 (87.2%)) with locoregionally advanced unresectable esophageal cancer received induction DCF. The response rate was 65.9% (complete/partial response: n = 31). After induction DCF, 24 patients (41.4%) had radical surgery and 7 (14.9%) had definitive CRT. RESULTS: The median overall survival (mOS) was significantly longer in patients received subsequent surgery compared with those with definitive CRT (mOS: 40.2 vs. 9.1 months, hazard ratio 3.33, 95% confidence interval 1.22-9.07, p = 0.02) and no definitive treatment (mOS: 40.2 vs. 6.3 months, hazard ratio 8.51, 95% confidence interval 3.7-19.73, p < 0.001). Patients who received surgery, female, and those with supraclavicular lymph node involvement had a better OS. Twenty-one patients (44.7%) developed grade 3/4 adverse events during induction DCF, and two died after chemotherapy because of trachea-esophageal fistula complicated with sepsis. Eleven patients who had surgery had postoperative complications and none had postoperative mortality. CONCLUSIONS: Induction DCF and subsequent conversion surgery offered a chance of cure with long-term survival benefit and manageable toxicities in patients with locoregionally advanced unresectable esophageal cancer.

Multimodal detection of flap endonuclease 1 activity through CRISPR/Cas12a trans-cleavage of single-strand DNA oligonucleotides.

Flap endonuclease 1 (FEN1) is an endonuclease that specially removes 5' single-stranded overhang of branched duplex DNA (5' flap). While FEN1 is essential in various DNA metabolism pathways for preventing the malignant transformation of cells, an unusual expression of FEN1 is often associated with tumor progression, making it a potential biomarker for cancer diagnosis and treatment. Here we report a multimodal detection of FEN1 activity based on CRISPR/Cas12a trans-cleavage of single-strand DNA oligonucleotides (ssDNA). A dumbbell DNA structure with a 5' flap was designed, which can be cleaved by the FEN1 and the dumbbell DNA is subsequently ligated by T4 DNA ligase. The resulting closed duplex DNA contains a specific protospacer adjacent motif (PAM) that activates trans-cleavage of ssDNA after binding to CRISPR/Cas12a-crRNA. The trans-cleavage is activated only once and is independent to length or sequence of the ssDNA, which allows efficient signal amplification and multimodal signals such as fluorescence or cleaved connection between magnetic microparticles (MMPs) and polystyrene microparticles (PMPs) that alters solution turbidity after magnetic separation. In addition, by loading the particle solution into a microfluidic chip, unconnected PMPs escaping from a magnetic separator are amassed at the particle dam, enabling a visible PMP accumulation length proportional to the FEN1 activity. This multimodal detection is selective to FEN1 and achieves a low limit of detection (LOD) with only 40 min of reaction time. Applying to cell lysates, higher FEN1 activity was detected in breast cancer cells, suggesting a great potential for cancer diagnosis.

Association of extent of resection and functional outcomes in diffuse low-grade glioma: systematic review & meta-analysis.

BACKGROUND: Surgical resection offers survival benefits in patients with diffuse low-grade glioma (DLGG) but its association with functional outcomes is uncertain. This systematic review assessed functional outcomes associated with extent of resection (EoR) in adults with DLGG. METHODS: We searched Medline, Embase and CENTRAL on the 19th of February 2021 for observational studies reporting functional outcomes after surgical resection for patients aged ≥ 18 years with a new diagnosis of supratentorial DLGG according to any World Health Organization classification of primary brain tumors. The Newcastle-Ottawa Scale (NOS) informed our risk of bias assessments. The proportion of patients returning to work within 12 months entered a random-effects meta-analysis. PROSPERO registration number CRD42021238387. RESULTS: There were seven eligible moderate to high-quality (NOS > 6) observational studies identified from 1,183 records involving 234 patients with DLGG. Functional outcomes reported included neurocognition (n = 2 studies), performance status (n = 3), quality of life (QoL) (n = 1) and return to work (n = 6). The proportion of patients who returned to work within 12 months of surgery was 84% (95% confidence interval [CI] 50-96%, I-squared = 38%, 5 studies) for gross total resection, 66% (95% CI 14-96%, I2 = 57%, 5 studies) for subtotal resection, and 31% (95% CI 4-82%, I2 = 0%, 4 studies) for partial resection. There was insufficient data on other functional outcomes for quantitative synthesis. CONCLUSION: A higher proportion of DLGG patients returned to work following gross total resection compared with those who had a subtotal or partial resection. Further studies with standardized assessments can clarify the association between EoR and different functional outcomes.

Itch-specific neurons in the ventrolateral orbital cortex selectively modulate the itch processing.

Itch is a cutaneous sensation that is critical in driving scratching behavior. The long-standing question of whether there are specific neurons for itch modulation inside the brain remains unanswered. Here, we report a subpopulation of itch-specific neurons in the ventrolateral orbital cortex (VLO) that is distinct from the pain-related neurons. Using a Tet-Off cellular labeling system, we showed that local inhibition or activation of these itch-specific neurons in the VLO significantly suppressed or enhanced itch-induced scratching, respectively, whereas the intervention did not significantly affect pain. Conversely, suppression or activation of pain-specific neurons in the VLO significantly affected pain but not itch. Moreover, fiber photometry and immunofluorescence verified that these itch- and pain-specific neurons are distinct in their functional activity and histological location. In addition, the downstream targets of itch- and pain-specific neurons were different. Together, the present study uncovers an important subpopulation of neurons in the VLO that specifically modulates itch processing.

PAM-flexible dual base editor-mediated random mutagenesis and self-activation strategies to improve CRISPRa potency.

VP64 is the smallest transactivation domain that can be packaged together with the sgRNA into a single adeno-associated virus (AAV) vector. However, VP64-based CRISPRa often exerts modest activation to the target gene when only one sgRNA is used. Herein, we used PAM-flexible dual base editor-mediated mutagenesis and self-activation strategies to derive VP64 variants with gain-of-function mutations. First, we generated an HEK293FT transgenic clone to stably expressing pTK-CRISPRa-GFP. The sgRNA of CRISPRa was designed to target the TK promoter, thereby allowing self-activation of CRISPRa-GFP. Base editors were then used to randomly mutagenesis VP64 in this transgenic cell. VP64 with enhanced potency would translate into increment of GFP fluorescence intensity, thereby allowing positive selection of the desired VP64 mutants. This strategy has enabled us to identify several VP64 variants that are more potent than the wild-type VP64. ΔCRISPRa derived from these VP64 variants also efficiently activated the endogenous promoter of anti-aging and longevity genes (KLOTHO, SIRT6, and NFE2L2) in human cells. Since the overall size of these ΔCRISPRa transgenes is not increased, it remains feasible for all-in-one AAV applications. The strategies described here can facilitate high-throughput screening of the desired protein variants and adapted to evolve any other effector domains.

Cellular uptake, tissue penetration, biodistribution, and biosafety of threose nucleic acids: Assessing in vitro and in vivo delivery.

Compared with siRNAs or other antisense oligonucleotides (ASOs), the chemical simplicity, DNA/RNA binding capability, folding ability of tertiary structure, and excellent physiological stability of threose nucleic acid (TNA) motivate scientists to explore it as a novel molecular tool in biomedical applications. Although ASOs reach the target cells/tumors, insufficient tissue penetration and distribution of ASOs result in poor therapeutic efficacy. Therefore, the study of the time course of drug absorption, biodistribution, metabolism, and excretion is of significantly importance. In this work, the pharmacokinetics and biosafety of TNAs in living organisms are investigated. We found that synthetic TNAs exhibited excellent biological stability, low cytotoxicity, and substantial uptake in living cells without transfection. Using U87 three-dimensional (3D) multicellular spheroids to mimic the in vivo tumor microenvironment, TNAs showed their ability to penetrate efficiently throughout the whole multicellular spheroid as a function of incubation time and concentration when the size of the spheroid is relatively small. Additionally, TNAs could be safely administrated into Balb/c mice and most of them distributed in the kidneys where they supposed to excrete from the body through the renal filtration system. We found that accumulation of TNAs in kidneys induced no pathological changes, and no acute structural and functional damage in renal systems. The favourable biocompatibility of TNA makes it attractive as a safe and effective nucleic acid-based therapeutic agent for practical biological applications.

Deep Brain Stimulation of the Interposed Nucleus Reverses Motor Deficits and Stimulates Production of Anti-inflammatory Cytokines in Ataxia Mice.

Cerebellum is one of the major targets of autoimmunity and cerebellar damage that leads to ataxia characterized by the loss of fine motor coordination and balance, with no treatment available. Deep brain stimulation (DBS) could be a promising treatment for ataxia but has not been extensively investigated. Here, our study aims to investigate the use of interposed nucleus of deep cerebellar nuclei (IN-DCN) for ataxia. We first characterized ataxia-related motor symptom of a Purkinje cell (PC)-specific LIM homeobox (Lhx)1 and Lhx5 conditional double knockout mice by motor coordination tests, and spontaneous electromyogram (EMG) recording. To validate IN-DCN as a target for DBS, in vivo local field potential (LFP) multielectrode array recording of IN-DCN revealed abnormal LFP amplitude surges in PCs. By synchronizing the EMG and IN-DCN recordings (neurospike and LFP) with high-speed video recordings, ataxia mice showed poorly coordinated movements associated with low EMG amplitude and aberrant IN-DCN neural firing. To optimize IN-DCN-DBS for ataxia, we tested DBS parameters from low (30 Hz) to high stimulation frequency (130 or 150 Hz), and systematically varied pulse width values (60 or 80 µs) to maximize motor symptom control in ataxia mice. The optimal IN-DCN-DBS parameter reversed motor deficits in ataxia mice as detected by animal behavioral tests and EMG recording. Mechanistically, cytokine array analysis revealed that anti-inflammatory cytokines such as interleukin (IL)-13 and IL-4 were upregulated after IN-DCN-DBS, which play key roles in neural excitability. As such, we show that IN-DCN-DBS is a promising treatment for ataxia and possibly other movement disorders alike.

Analytic approaches to clinical validation of results from preclinical models of glioblastoma: A systematic review.

INTRODUCTION: Analytic approaches to clinical validation of results from preclinical models are important in assessment of their relevance to human disease. This systematic review examined consistency in reporting of glioblastoma cohorts from The Cancer Genome Atlas (TCGA) or Chinese Glioma Genome Atlas (CGGA) and assessed whether studies included patient characteristics in their survival analyses. METHODS: We searched Embase and Medline on 02Feb21 for studies using preclinical models of glioblastoma published after Jan2008 that used data from TCGA or CGGA to validate the association between at least one molecular marker and overall survival in adult patients with glioblastoma. Main data items included cohort characteristics, statistical significance of the survival analysis, and model covariates. RESULTS: There were 58 eligible studies from 1,751 non-duplicate records investigating 126 individual molecular markers. In 14 studies published between 2017 and 2020 using TCGA RNA microarray data that should have the same cohort, the median number of patients was 464.5 (interquartile range 220.5-525). Of the 15 molecular markers that underwent more than one univariable or multivariable survival analyses, five had discrepancies between studies. Covariates used in the 17 studies that used multivariable survival analyses were age (76.5%), pre-operative functional status (35.3%), sex (29.4%) MGMT promoter methylation (29.4%), radiotherapy (23.5%), chemotherapy (17.6%), IDH mutation (17.6%) and extent of resection (5.9%). CONCLUSION: Preclinical glioblastoma studies that used TCGA for validation did not provide sufficient information about their cohort selection and there were inconsistent results. Transparency in reporting and the use of analytic approaches that adjust for clinical variables can improve the reproducibility between studies.

Using data mining technology to explore homocysteine at low levels.

ABSTRACT: A high homocysteine level is known to be an independent risk factor for cardiovascular diseases; however, whether or not low homocysteine level contributes to any damage to the body has not been extensively studied. Furthermore, acquiring healthy subject databases from domestic studies on homocysteine is not trivial. Therefore, we aimed to investigate the causality between serum homocysteine levels and health status and lifestyle factors, particularly with a focus on low serum homocysteine levels. Additionally, we discussed a systematic methodical platform for data collection and statistical analysis, using the descriptive analysis of the chi-square test, t test, multivariate analysis of variance, and logistic regression.This study was a cross-sectional analysis of 5864 subjects (i.e., clients of a health examination clinic) in Taipei, Taiwan during a general health check-up in 2017. The patients' personal information and associated links were excluded. A sample group was selected as per the health criteria defined for this research whose data were processed using SPSS for descriptive statistical analysis using chi-square test, t test, multivariate analysis of variance, and logistic regression analysis.Those working for >12 hours/day had a higher homocysteine level than those working for <12 hours/day (P < .001). The average serum homocysteine level was 7.9 and 8.6 mol/L for people with poor sleep quality and good sleep quality, respectively (P = .003). The homocysteine value of people known to have cancer was analyzed using the logistic regression analysis, revealing a Δodds value of 0.898. The percentage of subjects with a homocysteine value of ≤6.3 µmol/L, who perceived their health status as "not very good" or "very bad," was higher than those with a higher homocysteine level. The number of subjects who perceived their health as poor was higher than expected.The results suggest that the homocysteine level could be an effective health management indicator. We conclude that normal homocysteine level should not be ≤6.3 µmol/L. Moreover, homocysteine should not be considered as harmful and its fluctuations from the normal range could be utilized to infer a person's physical status for health management.

Targeted brain tumor imaging by using discrete biopolymer-coated nanodiamonds across the blood-brain barrier.

Short circulation lifetime, poor blood-brain barrier (BBB) permeability and low targeting specificity limit nanovehicles from crossing the vascular barrier and reaching the tumor site. Consequently, the precise diagnosis of malignant brain tumors remains a great challenge. This study demonstrates the imaging of photostable biopolymer-coated nanodiamonds (NDs) with tumor targeting properties inside the brain. NDs are labeled with PEGylated denatured bovine serum albumin (BSA) and tumor vasculature targeting tripeptides RGD. The modified NDs show high colloidal stability in different buffer systems. Moreover, it is found that discrete dcBSA-PEG-NDs cross the in vitro BBB model more effectively than aggregated NDs. Importantly, compared with the non-targeting NDs, RGD-dcBSA-PEG-NDs can selectively target the tumor site in U-87 MG bearing mice after systemic injection. Overall, this discrete ND system enables efficacious brain tumor visualization with minimal toxicity to other major organs, and is worthy of further investigation into the applications as a unique platform for noninvasive theragnostics and/or thermometry at different stages of human diseases in the brain.

Might changes in diagnostic practice explain increasing incidence of brain and central nervous system tumors? A population-based study in Wales (United Kingdom) and the United States.

BACKGROUND: Increasing incidence of central nervous system (CNS) tumors has been noted in some populations. However, the influence of changing surgical and imaging practices has not been consistently accounted for. METHODS: We evaluated average annual percentage change (AAPC) in age- and gender-stratified incidence of CNS tumors by tumor subtypes and histological confirmation in Wales, United Kingdom (1997-2015) and the United States (2004-2015) using joinpoint regression. FINDINGS: In Wales, the incidence of histologically confirmed CNS tumors increased more than all CNS tumors (AAPC 3.62% vs 1.63%), indicating an increasing proportion undergoing surgery. Grade II and III glioma incidence declined significantly (AAPC -3.09% and -1.85%, respectively) but remained stable for those with histological confirmation. Grade IV glioma incidence increased overall (AAPC 3.99%), more markedly for those with histological confirmation (AAPC 5.36%), suggesting reduced glioma subtype misclassification due to increased surgery. In the United States, the incidence of CNS tumors increased overall but was stable for histologically confirmed tumors (AAPC 1.86% vs 0.09%) indicating an increase in patients diagnosed without surgery. An increase in grade IV gliomas (AAPC 0.28%) and a decline in grade II gliomas (AAPC -3.41%) were accompanied by similar changes in those with histological confirmation, indicating the overall trends in glioma subtypes were unlikely to be caused by changing diagnostic and clinical management. CONCLUSIONS: Changes in clinical practice have influenced the incidence of CNS tumors in the United Kingdom and the United States. These should be considered when evaluating trends and in epidemiological studies of putative risk factors for CNS tumors.

Penetrating the Blood-Brain Barrier by Self-Assembled 3D DNA Nanocages as Drug Delivery Vehicles for Brain Cancer Therapy.

The development of biocompatible drug delivery vehicles for cancer therapy in the brain remains a big challenge. In this study, we designed self-assembled DNA nanocages functionalized with or without blood-brain barrier (BBB)-targeting ligands, d and we investigated their penetration across the BBB. Our DNA nanocages were not cytotoxic and they were substantially taken up in brain capillary endothelial cells and Uppsala 87 malignant glioma (U-87 MG) cells. We found that ligand modification is not essential for this DNA system as the ligand-free DNA nanocages (LF-NCs) could still cross the BBB by endocytosis inin vitro and in vivo models. Our spherical DNA nanocages were more permeable across the BBB compared with tubular DNA nanotubes. Remarkably, in vivo studies revealed that DNA nanocages could carry anticancer drugs across the BBB and inhibit the tumor growth in a U-87 MG xenograft mouse model. This is the first example showing the potential of DNA nanocages as innovative delivery vehicles to the brain for cancer therapy. Unlike other delivery systems, our work suggest that a DNA nanocage-based platform provides a safe and cost-effective tool for targeted delivery to the brain and therapy for brain tumors.

Drains result in greater reduction of subdural width and midline shift in burr hole evacuation of chronic subdural haematoma.

BACKGROUND: Drain insertion following chronic subdural haematoma (CSDH) evacuation reduces recurrence and improves outcomes. The mechanism of this improvement is uncertain. We assessed whether drains result in improved postoperative imaging, and which radiological factors are associated with recurrence and functional outcome. METHODS: A multi-centre, prospective cohort study of CSDH patients was performed between May 2013 and January 2014. Patients aged > 16 years undergoing burr hole evacuation of primary CSDH with pre- and postoperative imaging were included in this subgroup analysis. Baseline and clinical details were collected. Pre- and postoperative maximal subdural width and midline shift (MLS) along with clot density were recorded. Primary outcomes comprised mRS at discharge and symptomatic recurrence requiring re-drainage. Comparisons were made using multiple logistic regression. RESULTS: Three hundred nineteen patients were identified for inclusion. Two hundred seventy-two of 319 (85%) patients underwent drain insertion at the time of surgery versus 45/319 (14%) who did not. Twenty-nine of 272 patients who underwent drain insertion experienced recurrence (10.9%) versus 9 of 45 patients without drain insertion (20.5%; p = 0.07). Overall change in median subdural width was significantly greater in the drain versus 'no drain' groups (11 mm versus 6 mm, p < 0.01). Overall change in median midline shift (MLS) was also significantly greater in the drain group (4 mm versus 3 mm, p < 0.01). On multivariate analysis, change in maximal width and MLS were significant predictors of recurrence, although only the former remained a significant predictor for functional outcome. CONCLUSIONS: The use of subdural drains results in significantly improved postoperative imaging in burr hole evacuation of CSDH, thus providing radiological corroboration for their recommended use.

CRISPR-based strategies for targeted transgene knock-in and gene correction.

The last few years have seen tremendous advances in CRISPR-mediated genome editing. Great efforts have been made to improve the efficiency, specificity, editing window, and targeting scope of CRISPR/Cas9-mediated transgene knock-in and gene correction. In this article, we comprehensively review recent progress in CRISPR-based strategies for targeted transgene knock-in and gene correction in both homology-dependent and homology-independent approaches. We cover homology-directed repair (HDR), synthesis-dependent strand annealing (SDSA), microhomology-mediated end joining (MMEJ), and homology-mediated end joining (HMEJ) pathways for a homology-dependent strategy and alternative DNA repair pathways such as non-homologous end joining (NHEJ), base excision repair (BER), and mismatch repair (MMR) for a homology-independent strategy. We also discuss base editing and prime editing that enable direct conversion of nucleotides in genomic DNA without damaging the DNA or requiring donor DNA. Notably, we illustrate the key mechanisms and design principles for each strategy, providing design guidelines for multiplex, flexible, scarless gene insertion and replacement at high efficiency and specificity. In addition, we highlight next-generation base editors that provide higher editing efficiency, fewer undesired by-products, and broader targeting scope.

Synthetic α-l-Threose Nucleic Acids Targeting BcL-2 Show Gene Silencing and in Vivo Antitumor Activity for Cancer Therapy.

We design and synthesize a sequence-defined α-l-threose nucleic acid (TNA) polymer, which is complementary to certain nucleotide sites of target anti-apoptotic proteins, BcL-2 involving in development and progression of tumors. Compared to scramble TNA, anti-BcL-2 TNA significantly suppresses target mRNA and protein expression in cancerous cells and shows antitumor activity in carcinoma xenografts, resulting in suppression of tumor cell growth and induction of tumor cell death. Together with good biocompatibility, very low toxicity, excellent specificity features, and strong binding affinity toward the complementary target RNAs, TNAs become new useful biomaterials and effective alternatives to traditional antisense oligonucleotides including locked nucleic acids, morpholino oligomers, and peptide nucleic acids in antisense therapy. Compared to conventional cancer therapy such as radiotherapy, surgery, and chemotherapy, we anticipate that this TNA-based polymeric system will work effectively in antisense cancer therapy and shortly start to play an important role in practical application.