A potent bioreducible ionizable lipid nanoparticle enables siRNA delivery for retinal neovascularization inhibition.

Small interfering RNA (siRNA) is emerging as a promising treatment for retinal neovascularization due to its specific inhibition of the expression of target genes. However, the clinical translation of siRNA drugs is hindered by the efficiency and safety of delivery vectors. Here, we describe the properties of a new bioreducible ionizable lipid nanoparticle (LNP) 2N12H, which is based on a rationally designed novel ionizable lipid called 2N12B. 2N12H exhibited degradation in response to the mimic cytoplasmic glutathione condition and ionization with a pKa value of 6.5, which remaining neutral at pH 7.4. At a nitrogen to phosphorus ratio of 5, 2N12H efficiently encapsulated and protected siRNA from degradation. Compared to the commercial vehicle Lipofectamine 2000, 2N12H demonstrated similar silencing efficiency and improved safety in the in vitro cell experiments. 2N12H/siVEGFA reduced the expression of VEGFA in retinal pigment epithelium cells and mouse retina, consequently suppressing cell migration and retinal neovascularization. In the mouse model, the therapeutic effect of 2N12H/siVEGFA was comparable to that of the clinical drug ranibizumab. Together, these results suggest the potential of this novel ionizable LNP to facilitate the development of nonviral ocular gene delivery systems.

pH-Responsive polymer boosts cytosolic siRNA release for retinal neovascularization therapy.

Small interfering RNA (siRNA) has a promising future in the treatment of ocular diseases due to its high efficiency, specificity, and low toxicity in inhibiting the expression of target genes and proteins. However, due to the unique anatomical structure of the eye and various barriers, delivering nucleic acids to the retina remains a significant challenge. In this study, we rationally design PACD, an A-B-C type non-viral vector copolymer composed of a hydrophilic PEG block (A), a siRNA binding block (B) and a pH-responsive block (C). PACDs can self-assemble into nanosized polymeric micelles that compact siRNAs into polyplexes through simple mixing. By evaluating its pH-responsive activity, gene silencing efficiency in retinal cells, intraocular distribution, and anti-angiogenesis therapy in a mouse model of hypoxia-induced angiogenesis, we demonstrate the efficiency and safety of PACD in delivering siRNA in the retina. We are surprised to discover that, the PACD/siRNA polyplexes exhibit remarkable intracellular endosomal escape efficiency, excellent gene silencing, and inhibit retinal angiogenesis. Our study provides design guidance for developing efficient nonviral ocular nucleic acid delivery systems.

Single femtosecond pulse writing of a bifocal lens.

In this Letter, a method for the fabrication of bifocal lenses is presented by combining surface ablation and bulk modification in a single laser exposure followed by the wet etching processing step. The intensity of a single femtosecond laser pulse was modulated axially into two foci with a designed computer-generated hologram (CGH). Such pulse simultaneously induced an ablation region on the surface and a modified volume inside the fused silica. After etching in hydrofluoric acid (HF), the two exposed regions evolved into a bifocal lens. The area ratio (diameter) of the two lenses can be flexibly adjusted via control of the pulse energy distribution through the CGH. Besides, bifocal lenses with a center offset as well as convex lenses were obtained by a replication technique. This method simplifies the fabrication of micro-optical elements and opens a highly efficient and simple pathway for complex optical surfaces and integrated imaging systems.

Single-cell RNA sequencing uncovers the cell type-dependent transcriptomic changes in the retrosplenial cortex after peripheral nerve injury.

The retrosplenial cortex (RSC) is a vital area for storing remote memory and has recently been found to undergo broad changes after peripheral nerve injury. However, little is known about the role of RSC in pain regulation. Here, we examine the involvement of RSC in the pain of mice with nerve injury. Notably, reducing the activities of calcium-/calmodulin-dependent protein kinase type II-positive splenial neurons chemogenetically increases paw withdrawal threshold and extends thermal withdrawal latency in mice with nerve injury. The single-cell or single-nucleus RNA-sequencing results predict enhanced excitatory synaptic transmissions in RSC induced by nerve injury. Local infusion of 1-naphthyl acetyl spermine into RSC to decrease the excitatory synaptic transmissions relieves pain and induces conditioned place preference. Our data indicate that RSC is critical for regulating physiological and neuropathic pain. The cell type-dependent transcriptomic information would help understand the molecular basis of neuropathic pain.

Efficient ocular delivery of siRNA via pH-sensitive vehicles for corneal neovascularization inhibition.

Corneal neovascularization (CoNV)-induced blindness is an enduring and challenging condition with limited management options. Small interfering RNA (siRNA) is a promising strategy for preventing CoNV. This study reported a new strategy using siVEGFA to silence vascular endothelial growth factor A (VEGFA) for CoNV treatment. To improve the efficacy of siVEGFA delivery, a pH-sensitive polycationic mPEG2k-PAMA30-P(DEA29-D5A29) (TPPA) was fabricated. TPPA/siVEGFA polyplexes enter cells via clathrin-mediated endocytosis, resulting in higher cellular uptake efficiency and comparable silencing efficiency than that of Lipofectamine 2000 in vitro. Hemolytic assays verified that TPPA safe in normal physiological environments (pH 7.4) but can easily destroy membranes in acidic mature endosomes (pH 4.0). Studies on the distribution of TPPA in vivo showed that it could prolong the retention time of siVEGFA and promote its penetration in the cornea. In a mouse model induced by alkali burn, TPPA efficiently delivered siVEGFA to the lesion site and achieved VEGFA silencing efficiency. Importantly, the inhibitory effect of TPPA/siVEGFA on CoNV was comparable to that of the anti-VEGF drug ranibizumab. Delivering siRNA using pH-sensitive polycations to the ocular environment provides a new strategy to efficiently inhibit CoNV.

Fresnel zone plate sculptured out of diamond by femtosecond laser for harsh environments.

With the rapid development of micro-optical applications, there is an increasing demand for micro-optical elements that can be made with minimal processing steps. Current research focuses on practical functionalities of optical performance, lightweight, miniaturization, and easy integration. As an important planar diffractive optical element, the Fresnel zone plate (FZP) provides a compact solution for focusing and imaging. However, the fabrication of FZPs with high quality out of hard and brittle materials remains challenging. Here, we report on the fabrication of diamond FZP by femtosecond laser direct writing. FZPs with the same outer diameter and different focal lengths of 250-1000 µm were made via ablation. The fabricated FZPs possess well-defined geometry and excellent focusing and imaging ability in the visible spectral range. Arrays of FZPs with different focal lengths were made for potential applications in imaging, sensing, and integrated optical systems.

Hierarchical DNA branch assembly-encoded fluorescent nanoladders for single-cell transcripts imaging.

Spatial visualization of single-cell transcripts is limited by signal specificity and multiplexing. Here, we report hierarchical DNA branch assembly-encoded fluorescent nanoladders, which achieve denoised and highly multiplexed signal amplification for single-molecule transcript imaging. This method first offers independent RNA-primed rolling circle amplification without nonspecific amplification based on circular DNAzyme. It then executes programmable DNA branch assembly on these amplicons to encode virtual signals for visualizing numbers of targets by FISH. In theory, more virtual signals can be encoded via the increase of detection spectral channels and repeats of the same sequences on barcode. Our method almost eliminates nonspecific amplification in fixed cells (reducing nonspecific spots of single cells from 16 to nearly zero), and achieves simultaneous quantitation of nine transcripts by using only two detection spectral channels. We demonstrate accurate RNA profiling in different cancer cells, and reveal diverse localization patterns for spatial regulation of transcripts.

Transcription factor-target gene regulatory network analysis in human lung adenocarcinoma.

Background: Transcription factors (TFs) play a crucial role in the occurrence and progression of lung adenocarcinoma (LUAD), and targeting TFs is an important direction for treating LUAD. However, targeting a single TF often fails to achieve satisfactory therapeutic outcomes. Furthermore, the regulatory TF-target gene networks involved in the development of LUAD is complex and not yet fully understood. Methods: In this study, we performed RNA sequencing (RNA-seq) to analyze the transcriptome profile of human LUAD tissues and matched adjacent nontumor tissues. We selected the differentially expressed TFs, performed enrichment analysis and survival curve analysis, and predicted the regulatory networks of the top differential TFs with their target genes. Finally, alternative splicing analyses were also performed. Results: We found that TFs GRHL3, SIX1, SIX2, SPDEF, and ETV4 were upregulated, while TAL1, EPAS1, SOX17, NR4A1, and EGR3 were significantly downregulated in LUAD tissues compared to normal tissues. We propose a potential GRHL3-CDH15-Wnt-ß-catenin pro-oncogenic signaling axis and a potential TAL1-ADAMTS1-vascular antioncogenic signaling axis. In addition, we found that alternative splicing of intron retention (IR), approximate IR (XIR), multi-IR (MIR), approximate MIR (XMIR), and approximate alternative exon ends (XAE) showed abnormally increased frequencies in LUAD tissues. Conclusions: These findings revealed a novel TF-target gene regulatory axis related to tumorigenesis and provided potential therapeutic targets and mechanisms for LUAD.

The molecular mechanism of sepsis-induced diaphragm dysfunction.

Background: No effective drugs for the treatment of sepsis-induced diaphragm dysfunction are currently available. Therefore, it is particularly important to clarify the molecular regulatory mechanism of this condition and subsequently implement effective treatment and prevention of sepsis-induced diaphragm dysfunction. Methods: A mouse model of diaphragm dysfunction was established via injection of lipopolysaccharide (LPS). An RNA-sequencing (RNA-seq) technique was used to detect the differentially expressed genes (DEGs) in the diaphragms of mice. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed for functional analysis of DEGs. The protein-protein interaction network obtained from the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) website was imported into Cytoscape, the key molecular regulatory network was constructed with CytoNCA, the ClueGo plugin was further used to analyze the core regulatory pathways of key molecular, and finally, the iRegulon plugin was used to the identify key transcription factors. Results: The genes upregulated after LPS treatment were involved in biological processes and pathways related to immune response; the genes downregulated after LPS treatment were mainly correlated with the muscle contraction. The expressions of several inflammation-related genes were upregulated after LPS treatment, of which tumor necrosis factor (Tnf), interleukin (Il)-1ß, and Il-6 assumed a core regulatory role in the network; meanwhile, the downregulated key genes included Col1a1, Uqcrfs1, Sdhb, and ATP5a1, among others. These key regulatory factors participated in the activation of Toll-like receptor (TLR) signaling pathway, nuclear factor (NF)-κB signaling pathway, and TNF signaling pathway as well as the inhibition of oxidative phosphorylation pathway, cardiac muscle contraction pathway, and citrate cycle pathway. Finally, RelA, IRF1, and STAT3, were identified as the key regulators in the early stage of diaphragmatic inflammatory response. Conclusions: Sepsis-induced diaphragm dysfunction in mice is closely correlated with the activation of TLR signaling pathway, NF-κB signaling pathway, and TNF signaling pathway and the inhibition of oxidative phosphorylation pathway, cardiac muscle contraction pathway, and citrate cycle pathway. Our findings provide insight into the molecular mechanism of sepsis-induced diaphragm dysfunction in mice and provide a promising new strategy for targeted treatment of diaphragm dysfunction.

[Effect of administration of acupuncture stimulation combined with Gushen Zhuyu Decoction on lumbar function in patients with disc herniation].

OBJECTIVE: To investigate the therapeutic effect of acupuncture stimulation combined with administration of"Gushen Zhuyu Tang"(decoction for consolidating kidney to eliminate blood stasis, DCKEBS) in the treatment of lumbar disc herniation (LDH) patients. METHODS: A total of 147 patients with LDH were randomly divided into DCKEBS, acupuncture and DCKEBS+acupuncture groups (n= 49 cases in each group). The patients of the acupuncture group received a) acupuncture stimulation of Dazhui (GV14), Ganshu (BL18), Shenshu (BL23), Tianshu (ST25), Yanglingquan (GB34), etc., b) fire needle pricking of the topical tendons, cord-like points, tender-points, c) row-needles stimulation of the attachment sites of muscles of the sacroiliac joint or crista iliaca, and d) acupotomy-debonding of the topical high-tension muscles, twice a week for 4 weeks. Those patients of the DCKEBS group were ordered to take DCKEBS [containing fried Yiyiren (Semen Coicis), Shanzhuyu (Fructus Corni), fried Baizhu (Rhizoma Astractylodis), Sangjisheng (Ramulus Loranthi), Duzhong (Cortex Eucommiae), Buguzhi (Fructus Psoraieae), etc.] 150 mL, twice daily, continuously for 4 weeks, and those of the DCKEBS+acupuncture group received the combined treatment mentioned above in the acupuncture and DCKEBS groups. The pain severity was assessed by using visual ana-logue scale (VAS, 0-10 points) and the modified Japan Orthopaedic Association questionnaire (M-JOA) score (0-30 points), separately, and the lumbar range of motion (ROM) and lumbar muscle strength were tested to evaluate the lumbar motor function. The levels of serum tumor necrosis factor α(TNF-α), matrix metalloproteinase-2 (MMP-2), and apoptosis related factors Caspase-3 and Caspase-9 were assayed using ELISA. The total effective rates of the three groups were compared. RESULTS: After the treatment, the VAS and M-JOA scores, contents of serum TNF-α, MMP-2, Caspase-3 and Caspase-9 were significantly decreased (P<0.01), and the myodynamia of lumbar muscular flexor and extensor was considerably increased (P<0.01) in the three groups, and the ROM angles of lumbar extending and buckling were increased (P<0.01) in the DCKEBS+acupuncture group compared with pretreatment. Comparison among the 3 groups showed that the VAS and M-JOA scores, and serum TNF-α, MMP-2, Caspase-3 and Caspase-9 contents of the DCKEBS+acupuncture group were significantly lower than those of both DCKEBS and acupuncture groups (P<0.01), while the ROM angles of lumbar extending and buckling, and the myodynamia of lumbar muscular flexor and extensor were obviously higher in the DCKEBS+acupuncture group than those of the DCKEBS and acupuncture groups (P<0.01). The total effective rate was 93.88%(46/49) in the DCKEBS+acupuncture group, higher than 75.51%(37/49) in the DCKEBS group and 71.43%(35/49) in the acupuncture group (P<0.05). CONCLUSION: Acupuncture combined with DCKEBS can relieve pain, improve lumbar muscle strength and lumbar movement function, and reduce serum TNF-α, MMP-2, Caspase-3 and Caspase-9 levels in LDH patients.

Prediction Model for Liquid-Assisted Femtosecond Laser Micro Milling of Quartz without Taper.

The strong nonlinear absorption effect and "cold" processing characteristics of femtosecond lasers make them uniquely advantageous and promising for the micro- and nanoprocessing of hard and brittle materials, such as quartz. Traditional methods for studying the effects of femtosecond laser parameters on the quality of the processed structure mainly use univariate analysis methods, which require large mounts of experiments to predict and achieve the desired experimental results. The method of design of experiments (DOE) provides a way to predict desirable experimental results through smaller experimental scales, shorter experimental periods and lower experimental costs. In this study, a DOE program was designed to investigate the effects of a serious of parameters (laser repetition frequency, pulse energy, scan speed, scan distance, scan mode, scan times and laser focus position) on the depth and roughness (Ra) of the fabricated structure through the liquid-assisted femtosecond laser processing of quartz. A prediction model between the response variables and the main parameters was defined and validated. Finally, several blind holes with a size of 50 × 50 µm2 and a depth of 200 µm were fabricated by the prediction model, which demonstrated the good consistency of the prediction model.

Branched immunochip-integrated pairwise barcoding amplification exploring the spatial proximity of two post-translational modifications in distinct cell subpopulations.

Investigating the spatial information of post-translational modifications (PTMs) in distinct cell subpopulations represents a new direction toward single-cell analysis. The specific capture of cell populations combined with PTM spatial proximity visualization making it practically challenging. Here, we develop branched immunochip-integrated pairwise barcoding amplification, termed biChip-PBA, which can perform the respective capture of cell subpopulations expressing different membrane proteins and successive PBA-based fluorescence imaging of PTM proximities. Our work may provide multilevel information for new insights into epigenetic regulation and cell function.

Znhit1 Regulates p21Cip1 to Control Mouse Lens Differentiation.

Purpose: The transparency of the ocular lens is essential for refracting and focusing light onto the retina, and transparency is controlled by many factors and signaling pathways. Here we showed a critical role of chromatin remodeler zinc finger HIT-type containing 1 (Znhit1) in maintaining lens transparency. Methods: To explore the roles of Znhit1 in lens development, the cre-loxp system was used to generate lens-specific Znhit1 knockout mice (Znhit1Mlr10-Cre; Znhit1 cKO). Morphological changes in mice lenses were examined using hematoxylin and eosin staining. RNA sequencing (RNA-seq) and assay for transposase accessible chromatin using sequencing (ATAC-seq) were applied to screen transcriptome changes. Immunofluorescence staining were performed to assess proteins distribution and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining were used for determining apoptosis. The mRNAs expression was examined by quantitative RT-PCR and proteins expression by Western blot. Results: Lens-specific conditional knockout mice had a severe cataract, microphthalmia phenotype, and seriously abnormal lens fiber cells differentiation. Deletion of Znhit1 in the lens resulted in decreased cell proliferation and increased cell apoptosis of the lens epithelia. ATAC-seq showed that Znhit1 deficiency increased chromatin accessibility of cyclin-dependent kinase inhibitors, including p57Kip2 and p21Cip1, and upregulated the expression of these genes in mRNA and protein levels. And we also showed that loss of Znhit1 lead to lens fibrosis by upregulating the expression of p21Cip1. Conclusions: Our findings suggested that Znhit1 is required for the survival of lens epithelial cells. The loss of Znhit1 leads to the overexpression of p21Cip1, further resulting in lens fibrosis, and impacted the establishment of lens transparency.

Camrelizumab combined with anlotinib for the treatment of small cell lung cancer: a case report and literature review.

Data in 2020 show that lung cancer is the second most common cancer with the highest morbidity and mortality in the world, among which small cell lung cancer (SCLC) accounts for about 15% of the total number of lung cancers, but the number of deaths accounts for 25% of lung cancers. SCLC is an aggressive malignancy disease with a high recurrence rate and poor prognosis. The survival rate of small cell lung cancer is lower than other types of lung cancer and the prognosis is very poor. At present, there is still a lack of effective therapeutic options for SCLC after the failure of second-line treatment. However, studies have shown that anti-vascular therapy and programmed death-1 (PD-1) inhibitors are effective in SCLC. In the present case, a combination therapy of camrelizumab, a PD-1 inhibitor, and anlotinib (an anti-angiogenic drug) was administered to treat a 58-year-old male patient with programmed cell death-Ligand 1 (PD-L1) negative metastatic SCLC accompanied by primary tongue cancer. A total of 28 cycles were used from March 2020 to November 2021. Until November 2021, the survival time of the patient is 31 months; he has survived for 19 months with no disease progression, and is currently classified as complete response (CR). Our study demonstrates that camrelizumab plus anlotinib may be a promising treatment option for patients with metastatic SCLC.

A Systematic Evaluation of Supervised Machine Learning Algorithms for Cell Phenotype Classification Using Single-Cell RNA Sequencing Data.

The new technology of single-cell RNA sequencing (scRNA-seq) can yield valuable insights into gene expression and give critical information about the cellular compositions of complex tissues. In recent years, vast numbers of scRNA-seq datasets have been generated and made publicly available, and this has enabled researchers to train supervised machine learning models for predicting or classifying various cell-level phenotypes. This has led to the development of many new methods for analyzing scRNA-seq data. Despite the popularity of such applications, there has as yet been no systematic investigation of the performance of these supervised algorithms using predictors from various sizes of scRNA-seq datasets. In this study, 13 popular supervised machine learning algorithms for cell phenotype classification were evaluated using published real and simulated datasets with diverse cell sizes. This benchmark comprises two parts. In the first, real datasets were used to assess the computing speed and cell phenotype classification performance of popular supervised algorithms. The classification performances were evaluated using the area under the receiver operating characteristic curve, F1-score, Precision, Recall, and false-positive rate. In the second part, we evaluated gene-selection performance using published simulated datasets with a known list of real genes. The results showed that ElasticNet with interactions performed the best for small and medium-sized datasets. The NaiveBayes classifier was found to be another appropriate method for medium-sized datasets. With large datasets, the performance of the XGBoost algorithm was found to be excellent. Ensemble algorithms were not found to be significantly superior to individual machine learning methods. Including interactions in the ElasticNet algorithm caused a significant performance improvement for small datasets. The linear discriminant analysis algorithm was found to be the best choice when speed is critical; it is the fastest method, it can scale to handle large sample sizes, and its performance is not much worse than the top performers.

[Core stability training combined with acupuncture in treatment of chronic nonspecific low back pain: a prospective randomized controlled trial].

OBJECTIVE: To investigate the clinical effect of core stability training combined with acupuncture in the treatment of chronic nonspecific low back pain (CLBP). METHODS: Seventy-five CLBP patients were randomly divided into experimental group (n=38) and control group (n=37) according to a random number table. Patients in the control group were required to perform core stability training, whereas those in the experimental group received core stability training combined with fire needle acupuncture, once every two days, three times per week, for four successive weeks. The Oswestry disability index (ODI), visual analogue scale (VAS), lumbar muscular endurance index, clinical efficacy, as well as average electromyographic (AEMG), root mean square (RMS), median frequency (MF), and average median frequency (AMF) values during multifidus muscle contraction in the two groups before and after the treatment were compared. RESULTS: After treatment, ODI, VAS, MF, and AMF of the two groups were lower than those before the treatment (P<0.01), while the lumbar static and dynamic muscular endurance, AEMG, and RMS values were higher (P<0.01). The ODI, VAS, MF, and AMF of the experimental group significantly declined as compared with those of the control group (P<0.01), whereas the lumbar static and dynamic muscular endurance, AEMG, and RMS values were elevated (P<0.01). The total effective rate of the experimental group was 97.14%(34/35), higher than 85.71%(30/35) of the control group(P<0.01). CONCLUSION: Core stability training combined with acupuncture effectively enhances lumbar muscular endurance, improves electromyographic signals of multifidus muscle and lumbar function, and relieves pain, implying the good efficacy of such combined therapy in treating CLBP.

A bifunctional chemical signature enabling RNA 4-thiouridine enrichment sequencing with single-base resolution.

Both sequence enrichment and base resolution are essential for accurate sequencing analysis of low-abundance RNA. Yet they are hindered by the lack of molecular tools. Here we report a bifunctional chemical signature for RNA 4-thiouridine (4sU) enrichment sequencing with single-base resolution. This chemical signature is designed for specific 4sU labeling with two functional parts. One part is a distal alkynyl group for the biotin-assisted pulldown enrichment of target molecules via click chemistry crosslinking. The other part is a -NH group proximal to the pyrimidine ring of 4sU. It allows 4sU-to-cytosine transition during the polymerase-catalyzed extension reaction based on altering hydrogen-bonding patterns. Ultimately, the 4sU-containing RNA molecules can be enriched and accurately analyzed by single-base resolution sequencing. The proposed method also holds great potential to investigate transcriptome dynamics integrated with high-throughput sequencing.

Variable focus convex microlens array on K9 glass substrate based on femtosecond laser processing and hot embossing lithography.

We propose a high-precision method for the fabrication of variable focus convex microlens arrays on K9 glass substrate by combining femtosecond laser direct writing and hot embossing lithography. A sapphire master mold with a blind cylindrical hole array was prepared first by femtosecond laser ablation. The profile control of microlenses dependent on the temperature and the diameter of the blind hole in the sapphire mold was investigated. The curvature radius of the microlens decreased with temperature and increased with diameter. Uniform convex microlens arrays were fabricated with good imaging performance. Further, variable focus convex microlens arrays were fabricated by changing the diameter of the blind hole in sapphire, which produced the image at variable z planes. This method provides a highly precise fabrication of convex microlens arrays and is well suited for batch production of micro-optical elements.

MiR-202-3p inhibits the proliferation and metastasis of lung adenocarcinoma cells by targeting RRM2.

Background: Lung adenocarcinoma (LUAD) is the most common type of lung cancer, and its pathogenesis is still unclear. The present study aimed to investigate the role of miR-202-3p and its downstream target gene, ribonucleotide reductase regulatory subunit M2 (RRM2), in the occurrence and development of LUAD and elucidate the correlation between RRM2 and the clinicopathological stage and prognosis of LUAD. Methods: The expression of miR-202-3p was analyzed using the CancerMIRNome database and quantitative polymerase chain reaction (qPCR). The effects of miR-202-3p and RRM2 on the proliferation, migration, and invasion of A549 cells were analyzed. A dual luciferase reporter assay was used to verify the targeting of miR-202-3p and RRM2. Additionally, the correlation between RRM2 expression and clinicopathology was analyzed. Results: (I) MiR-202-3p was lowly expressed in LUAD and the LUAD cell lines. qPCR confirmed that microRNA (miRNA) transfection was effective and sufficient for subsequent experiments. (II) MiR-202-3p inhibited the proliferation, invasion, and migration of LUAD cells. (III) There was a targeting relationship between miR-202-3p and RRM2, and miR-202-3p affected the expression of the RRM2 protein. RRM2 was highly expressed in lung cancer tissue. (IV) RRM2 was associated with the clinicopathological staging of lung cancer. The prognosis of patients with low RRM2 expression was better, and the prognostic sensitivity of RRM2 to lung cancer was high. RRM2 may exert its effects via the Notch pathway. (V) Si-RRM2 inhibited the expression of the RRM2 protein. RRM2 promoted the proliferation, migration, and invasion of LUAD cells. A miR-202-3p inhibitor restored the inhibitory effect of si-RRM2 on LUAD cells. Conclusions: MiR-202-3p was lowly expressed in lung cancer tissue. MiR-202-3p overexpression inhibited the proliferation and metastasis of lung cancer cells. RRM2 was highly expressed in lung cancer tissue and promoted the proliferation and metastasis of lung cancer cells. MiR-202-3p targeted and inhibited RRM2, thereby reducing the proliferation and metastasis of LUAD cells. LUAD patients with low RRM2 expression had a better prognosis, and the expression level of RRM2 was correlated with the clinical characteristics of lung cancer patients.