Establishment of a cholangiocarcinoma risk evaluation model based on mucin expression levels.

BACKGROUND: Cholangiocarcinoma (CCA) is a highly malignant cancer, characterized by frequent mucin overexpression. MUC1 has been identified as a critical oncogene in the progression of CCA. However, the comprehensive understanding of how the mucin family influences CCA progression and prognosis is still incomplete. AIM: To investigate the functions of mucins on the progression of CCA and to establish a risk evaluation formula for stratifying CCA patients. METHODS: Single-cell RNA sequencing data from 14 CCA samples were employed for elucidating the roles of mucins, complemented by bioinformatic analyses. Subsequent validations were conducted through spatial transcriptomics and immunohistochemistry. The construction of a risk evaluation model utilized the least absolute shrinkage and selection operator regression algorithm, which was further confirmed by independent cohorts and diverse data types. RESULTS: CCA tumor cells with elevated levels of MUC1 and MUC4 showed activated nucleotide metabolic pathways and increased invasiveness. MUC5AC-high cells were found to promote CCA progression through WNT signaling. MUC5B-high cells exhibited robust cellular oxidation activities, leading to resistance against antitumoral treatments. MUC13-high cells were observed to secret chemokines, recruiting and transforming macrophages into the M2-polarized state, thereby suppressing antitumor immunity. MUC16-high cells were found to promote tumor progression through interleukin-1/nuclear factor kappa-light-chain-enhancer of activated B cells signaling upon interaction with neutrophils. Utilizing the expression levels of these mucins, a risk factor evaluation formula for CCA was developed and validated across multiple cohorts. CCA samples with higher risk factors exhibited stronger metastatic potential, chemotherapy resistance, and poorer prognosis. CONCLUSION: Our study elucidates the functional mechanisms through which mucins contribute to CCA development, and provides tools for risk stratification in CCA.

[The Optimal Storage Condition and Storage Time of Umbilical Cord Blood from Collection to Preparation].

OBJECTIVE: To explore the optimal storage condition and time of umbilical cord blood from collection to preparation. METHODS: Collect cord blood samples from 30 healthy newborns, with each new born's umbilical cord blood was divided into two parts on average. One part was stored in cold storage (4 ℃) and the other was stored at room temperature (20-24 ℃). Samples were taken at 24, 36, 48, 60 and 72 h, respectively, total nucleated cells (TNC) count and TNC viability was analyzed. Flow cytometry was used to detect the ratio of viable CD34+ cells to viable CD45+ cells and viability of CD34+ cells, and colony-forming unit-granulocyte-macrophage (CFU-GM) count was performed by hematopoietic progenitor cell colony culture. The change trend of each index over time was observed, and the differences in each index was compared between cold storage and room temperature storage under the same storage time. RESULTS: The TNC count (r 4 ℃=-0.9588， r 20-24 ℃=-0.9790), TNC viability (r 4 ℃=-0.9941， r 20-24 ℃=-0.9970), CD34+ cells viability (r 4 ℃=-0.9932， r 20-24 ℃=-0.9828) of cord blood stored in cold storage (4 ℃) and room temperature storage (20-24 ℃) showed a consistent downward trend with the prolongation of storage time. The percentage of viable CD34+ cells (r 4 ℃=0.9169， r 20-24 ℃=0.7470) and CFU-GM count (r 4 ℃=-0.2537， r 20-24 ℃=-0.8098) did not show consistent trends. When the storage time was the same, the TNC count, TNC viability, CD34+ cells viability and CFU-GM count of cord blood stored in cold storage were higher than those stored at room temperature. Under the same storage time (24, 36, 48, 60 or 72 h), TNC viability in room temperature storage was significantly lower than that in cold storage (P <0.001), but TNC count, percentage of viable CD34+ cells and CFU-GM count were not significantly different between room temperature storage and cold storage. When stored at room temperature for 24 h and 36 h, the viability of CD34+ cells was significantly lower than that in cold storage (P <0.001, P <0.01), when the storage time for 48, 60 and 72 h, there was no significant difference in the CD34+ cells viability between room temperature storage and cold storage. CONCLUSION: It is recommended that cord blood be stored in cold storage (4 ℃) from collection to preparation, and processed as soon as possible.

Association Study of Pleural Mesothelioma and Oncogenic Simian Virus 40 in the Crocidolite-Contaminated Area of Dayao County, Yunnan Province, Southwest China.

Background: In Dayao County, Chuxiong Yi Autonomous Prefecture, Yunnan Province, Southwest China, 5% of the surface is scattered with blue asbestos, which has a high incidence of pleural mesothelioma (PMe). Simian virus 40 (SV40) is a small circular double-stranded DNA polyomavirus that can cause malignant transformation of normal cells of various human and animal tissue types and promote tumor growth. In this study, we investigate whether oncogenic SV40 is associated with the occurrence of PMe in the crocidolite-contaminated area of Dayao County, Yunnan Province, Southwest China. Methods: Tumor tissues from 51 patients with PMe (40 of whom had a history of asbestos exposure) and pleural tissues from 12 non-PMe patients (including diseases such as pulmonary maculopathy and pulmonary tuberculosis) were collected. Three pairs of low-contamination risk primers (SVINT, SVfor2, and SVTA1) were used to detect the gene fragment of SV40 large T antigen (T-Ag) by polymerase chain reaction (PCR). The presence of SV40 T-Ag in PMe tumor tissues and PMe cell lines was detected by Western blotting and immunohistochemical staining with SV40-related antibodies (PAb 101 and PAb 416). Results: PCR, Western blotting, and immunohistochemical staining results showed that the Met5A cell line was positive for SV40 and contained the SV40 T-Ag gene and protein. In contrast, the various PMe cell lines NCI-H28, NCI-H2052, and NCI-H2452 were negative for SV40. PCR was negative for all three sets of low-contamination risk primers in 12 non-PMe tissues and 51 PMe tissues. SV40 T-Ag was not detected in 12 non-PMe tissues or 51 PMe tissues by immunohistochemical staining. Conclusion: Our data suggest that the occurrence of PMe in the crocidolite-contaminated area of Yunnan Province may not be related to SV40 infection and that crocidolite exposure may be the main cause of PMe. The Clinical Trial Registration number: 2020-YXLL20.

Dual-space disentangled-multimodal network (DDM-net) for glioma diagnosis and prognosis with incomplete pathology and genomic data.

Objective. Effective fusion of histology slides and molecular profiles from genomic data has shown great potential in the diagnosis and prognosis of gliomas. However, it remains challenging to explicitly utilize the consistent-complementary information among different modalities and create comprehensive representations of patients. Additionally, existing researches mainly focus on complete multi-modality data and usually fail to construct robust models for incomplete samples.Approach. In this paper, we propose adual-space disentangled-multimodal network (DDM-net)for glioma diagnosis and prognosis. DDM-net disentangles the latent features generated by two separate variational autoencoders (VAEs) into common and specific components through a dual-space disentangled approach, facilitating the construction of comprehensive representations of patients. More importantly, DDM-net imputes the unavailable modality in the latent feature space, making it robust to incomplete samples.Main results. We evaluated our approach on the TCGA-GBMLGG dataset for glioma grading and survival analysis tasks. Experimental results demonstrate that the proposed method achieves superior performance compared to state-of-the-art methods, with a competitive AUC of 0.952 and a C-index of 0.768.Significance. The proposed model may help the clinical understanding of gliomas and can serve as an effective fusion model with multimodal data. Additionally, it is capable of handling incomplete samples, making it less constrained by clinical limitations.

The characteristics of fungal responses to uranium mining activities and analysis of their tolerance to uranium.

The influence of uranium (U) mining on the fungal diversity (FD) and communities (FC) structure was investigated in this work. Our results revealed that soil FC richness and FD indicators obviously decreased due to U, such as Chao1, observed OTUs and Shannon index (P<0.05). Moreover, the abundances of Mortierella, Gibberella, and Tetracladium were notably reduced in soil samples owing to U mining activities (P<0.05). In contrast, the abundances of Cadophora, Pseudogymnoascus, Mucor, and Sporormiella increased in all soil samples after U mining (P<0.05). Furthermore, U mining not only dramatically influenced the Plant_Pathogen guild and Saprotroph and Pathotroph modes (P<0.05), but also induced the differentiation of soil FC and the enrichment of the Animal_Pathogen-Soil_Saprotroph and Endophyte guilds and Symbiotroph and Pathotroph Saprotroph trophic modes. In addition, various fungal populations and guilds were enriched to deal with the external stresses caused by U mining in different U mining areas and soil depths (P<0.05). Finally, nine U-tolerant fungi were isolated and identified with a minimum inhibitory concentration range of 400-600 mg/L, and their adsorption efficiency for U ranged from 11.6% to 37.9%. This study provides insights into the impact of U mining on soil fungal stability and the response of fungi to U mining activities, as well as aids in the screening of fungal strains that can be used to promote remediation of U mining sites on plateaus.

Development of LAG-3/FGL1 blocking peptide and combination with radiotherapy for cancer immunotherapy.

Aside from antibodies, peptides show great potential as immune checkpoint inhibitors (ICIs) due to several advantages, such as better tumor penetration and lower cost. Lymphocyte-activation gene 3 (LAG-3) is an immune checkpoint which can induce T cell dysfunction through interaction with its soluble ligand fibrinogen like protein-1 (FGL1). Here, we found that LAG-3 expression was higher than programmed cell death protein 1 (PD-1) in multiple human cancers by TCGA databases, and successfully identified a LAG-3 binding peptide LFP-6 by phage display bio-panning, which specifically blocks the interaction of LAG-3/FGL1 but not LAG-3/MHC-II. Subsequently, d-amino acids were introduced to substitute the N- and C-terminus of LFP-6 to obtain the proteolysis-resistant peptide LFP-D1, which restores T cell function in vitro and inhibits tumor growth in vivo. Further, a bispecific peptide LFOP targeting both PD-1/PD-L1 and LAG-3/FGL1 was designed by conjugating LFP-D1 with PD-1/PD-L1 blocking peptide OPBP-1(8-12), which activates T cell with enhanced proliferation and IFN-γ production. More importantly, LFOP combined with radiotherapy significantly improve the T cell infiltration in tumor and elevate systemic antitumor immune response. In conclusion, we developed a novel peptide blocking LAG-3/FGL1 which can restore T cell function, and the bispecific peptide synergizes with radiotherapy to further enhance the antitumor immune response.

Graphene nanoribbons grown in hBN stacks for high-performance electronics.

Van der Waals encapsulation of two-dimensional materials in hexagonal boron nitride (hBN) stacks is a promising way to create ultrahigh-performance electronic devices1-4. However, contemporary approaches for achieving van der Waals encapsulation, which involve artificial layer stacking using mechanical transfer techniques, are difficult to control, prone to contamination and unscalable. Here we report the transfer-free direct growth of high-quality graphene nanoribbons (GNRs) in hBN stacks. The as-grown embedded GNRs exhibit highly desirable features being ultralong (up to 0.25 mm), ultranarrow (<5 nm) and homochiral with zigzag edges. Our atomistic simulations show that the mechanism underlying the embedded growth involves ultralow GNR friction when sliding between AA'-stacked hBN layers. Using the grown structures, we demonstrate the transfer-free fabrication of embedded GNR field-effect devices that exhibit excellent performance at room temperature with mobilities of up to 4,600 cm2 V-1 s-1 and on-off ratios of up to 106. This paves the way for the bottom-up fabrication of high-performance electronic devices based on embedded layered materials.

Seeded growth of single-crystal black phosphorus nanoribbons.

Two-dimensional materials have emerged as an important research frontier for overcoming the challenges in nanoelectronics and for exploring new physics. Among them, black phosphorus, with a combination of a tunable bandgap and high mobility, is one of the most promising systems. In particular, black phosphorus nanoribbons show excellent electrostatic gate control, which can mitigate short-channel effects in nanoscale transistors. Controlled synthesis of black phosphorus nanoribbons, however, has remained an outstanding problem. Here we report large-area growth of black phosphorus nanoribbons directly on insulating substrates. We seed the chemical vapour transport growth with black phosphorus nanoparticles and obtain uniform, single-crystal nanoribbons oriented exclusively along the [100] crystal direction. With comprehensive structural calculations, we discover that self-passivation at the zigzag edges holds the key to the preferential one-dimensional growth. Field-effect transistors based on individual nanoribbons exhibit on/off ratios up to ~104, confirming the good semiconducting behaviour of the nanoribbons. These results demonstrate the potential of black phosphorus nanoribbons for nanoelectronic devices and also provide a platform for investigating the exotic physics in black phosphorus.

A New Species of Ganoderma (Ganodermataceae, Polyporales) from Southern China and Optimum Condition for Mycelia Production.

The present study sought to propose Ganoderma guixiense sp. nov. as a new species based on phenotypic and genotypic evidence. Phylogenetic analyses were carried out based on the internal transcribed spacer (ITS), the large subunit of nuclear ribosomal RNA gene (nLSU), and the second subunit of RNA polymerase II (RPB2) sequence data. G. guixiense has been characterized by pileate basidiomata, long stipe, in addition to reddish-black zonate pileal surface. Basidiospores are broadly ellipsoid with one end tapering at maturity, and measuring 9-12.8 × 6.5-9.3 µm. Basidia are oval to subglobose. This study marks the first exploration of the biological characteristics of G. guixiense. The result indicated that the optimal medium of mycelial growth was observed on malt extract agar (MEA) and yeast extract peptone dextrose agar (YPD) while the optimal temperature was found to be 25-30 °C with pH range of 6-7.

Hemin blocks TIGIT/PVR interaction and induces ferroptosis to elicit synergistic effects of cancer immunotherapy.

The immune checkpoint TIGIT/PVR blockade exhibits significant antitumor effects through activation of NK and CD8+ T cell-mediated cytotoxicity. Immune checkpoint blockade (ICB) could induce tumor ferroptosis through IFN-γ released by immune cells, indicating the synergetic effects of ICB with ferroptosis in inhibiting tumor growth. However, the development of TIGIT/PVR inhibitors with ferroptosis-inducing effects has not been explored yet. In this study, the small molecule Hemin that could bind with TIGIT to block TIGIT/PVR interaction was screened by virtual molecular docking and cell-based blocking assay. Hemin could effectively restore the IL-2 secretion from Jurkat-hTIGIT cells. Hemin reinvigorated the function of CD8+ T cells to secrete IFN-γ and the elevated IFN-γ could synergize with Hemin to induce ferroptosis in tumor cells. Hemin inhibited tumor growth by boosting CD8+ T cell immune response and inducing ferroptosis in CT26 tumor model. More importantly, Hemin in combination with PD-1/PD-L1 blockade exhibited more effective antitumor efficacy in anti-PD-1 resistant B16 tumor model. In summary, our finding indicated that Hemin blocked TIGIT/PVR interaction and induced tumor cell ferroptosis, which provided a new therapeutic strategy to combine immunotherapy and ferroptosis for cancer treatment.

The Emerging Function and Promise of tRNA-Derived Small RNAs in Cancer.

Fragments derived from tRNA, called tRNA-derived small RNAs (tsRNAs), have attracted widespread attention in the past decade. tsRNAs are widespread in prokaryotic and eukaryotic transcriptome, which contains two main types, tRNA-derived fragments (tRFs) and tRNA-derived stress-inducing RNA (tiRNAs), derived from the precursor tRNAs or mature tRNAs. According to differences in the cleavage position, tRFs can be divided into tRF-1, tRF-2, tRF-3, tRF-5, and i-tRF, whereas tiRNAs can be divided into 5'-tiRNA and 3'-tiRNA. Studies have found that tRFs and tiRNAs are abnormally expressed in a variety of human malignant tumors, promote or inhibit the proliferation and apoptosis of cancer cells by regulating the expression of oncogene, and play an important role in the aggressive metastasis and progression of tumors. This article reviews the biological origins of various tsRNAs, introduces their functions and new concepts of related mechanisms, and focuses on the molecular mechanisms of tsRNAs in cancer, including breast cancer, prostate cancer, colorectal cancer, lung cancer, b-cell lymphoma, and chronic lymphoma cell leukemia. Lastly, this article puts forward some unresolved problems and future research prospects.

The scaffold protein AXIN1: gene ontology, signal network, and physiological function.

AXIN1, has been initially identified as a prominent antagonist within the WNT/ß-catenin signaling pathway, and subsequently unveiled its integral involvement across a diverse spectrum of signaling cascades. These encompass the WNT/ß-catenin, Hippo, TGFß, AMPK, mTOR, MAPK, and antioxidant signaling pathways. The versatile engagement of AXIN1 underscores its pivotal role in the modulation of developmental biological signaling, maintenance of metabolic homeostasis, and coordination of cellular stress responses. The multifaceted functionalities of AXIN1 render it as a compelling candidate for targeted intervention in the realms of degenerative pathologies, systemic metabolic disorders, cancer therapeutics, and anti-aging strategies. This review provides an intricate exploration of the mechanisms governing mammalian AXIN1 gene expression and protein turnover since its initial discovery, while also elucidating its significance in the regulation of signaling pathways, tissue development, and carcinogenesis. Furthermore, we have introduced the innovative concept of the AXIN1-Associated Phosphokinase Complex (AAPC), where the scaffold protein AXIN1 assumes a pivotal role in orchestrating site-specific phosphorylation modifications through interactions with various phosphokinases and their respective substrates.

Self-Termination of Borophene Edges.

Due to boron's unique bonding nature, planar boron materials, including borophenes, boron nanoclusters, and nanoribbons, show very puzzling features, especially the superior stability of the free-standing planar boron edges. Here, we present a systematic investigation of the bonding configurations of various edges of borophene. Because of the flexibility of forming either three-center two-electron (3c-2e) or two-center two-electron bonds (2c-2e), an edge of borophene tends to be self-terminated by adopting a different bonding configuration at the edge from that in bulk. Among various borophene edge types, the double-chain-terminated flat edge is found to be significantly stable. As a consequence, we found that the double- and triple-chain borophene nanoribbons with a triangular lattice and wider ribbons with hexagonal holes in the central area are more stable than the quadruple-chain borophene nanoribbon. This study greatly deepens our understanding of the bonding configurations, electronic properties, and stabilities of planar boron nanostructures and paves the way for the rational design and synthesis of various boron materials.

Multiple Origins of Bioluminescence in Beetles and Evolution of Luciferase Function.

Bioluminescence in beetles has long fascinated biologists, with diverse applications in biotechnology. To date, however, our understanding of its evolutionary origin and functional variation mechanisms remains poor. To address these questions, we obtained high-quality reference genomes of luminous and nonluminous beetles in 6 Elateroidea families. We then reconstructed a robust phylogenetic relationship for all luminous families and related nonluminous families. Comparative genomic analyses and biochemical functional experiments suggested that gene evolution within Elateroidea played a crucial role in the origin of bioluminescence, with multiple parallel origins observed in the luminous beetle families. While most luciferase-like proteins exhibited a conserved nonluminous amino acid pattern (TLA346 to 348) in the luciferin-binding sites, luciferases in the different luminous beetle families showed divergent luminous patterns at these sites (TSA/CCA/CSA/LVA). Comparisons of the structural and enzymatic properties of ancestral, extant, and site-directed mutant luciferases further reinforced the important role of these sites in the trade-off between acyl-CoA synthetase and luciferase activities. Furthermore, the evolution of bioluminescent color demonstrated a tendency toward hypsochromic shifts and variations among the luminous families. Taken together, our results revealed multiple parallel origins of bioluminescence and functional divergence within the beetle bioluminescent system.

Tip Growth of Quasi-Metallic Bilayer Graphene Nanoribbons with Armchair Chirality.

Graphene nanoribbons (GNRs), quasi one-dimensional (1D) narrow strips of graphene, have shown promise for high-performance nanoelectronics due to their exceptionally high carrier mobility and structurally tunable bandgaps. However, producing chirality-uniform GNRs on insulating substrates remains a big challenge. Here, we report the successful growth of bilayer GNRs with predominantly armchair chirality and ultranarrow widths (<5 nm) on insulating hexagonal boron nitride (h-BN) substrates using chemical vapor deposition (CVD). The growth of GNRs is catalyzed by transition metal nanoparticles, including Fe, Co, and Ni, through a unique tip-growth mechanism. Notably, GNRs catalyzed by Ni exhibit a high purity (97.3%) of armchair chirality. Electron transport measurements indicate that the ultrathin bilayer armchair GNRs exhibit quasi-metallic behavior. This quasi-metallicity is further supported by density functional theory (DFT) calculations, which reveal a significantly reduced bandgap in bilayer armchair GNRs. The chirality-specific GNRs reported here offer promising advancements for the application of graphene in nanoelectronics.

Clonal Hematopoiesis of Indeterminate Potential in Chronic Thromboembolic Pulmonary Hypertension: A Multicenter Study.

BACKGROUND: The pathogenesis of chronic thromboembolic pulmonary hypertension (CTEPH) is multifactorial and growing evidence has indicated that hematological disorders are involved. Clonal hematopoiesis of indeterminate potential (CHIP) has recently been associated with an increased risk of both hematological malignancies and cardiovascular diseases. However, the prevalence and clinical relevance of CHIP in patients with CTEPH remains unclear. METHODS: Using stepwise calling on next-generation sequencing data from 499 patients with CTEPH referred to 3 centers between October 2006 and December 2021, CHIP mutations were identified. We associated CHIP with all-cause mortality in patients with CTEPH. To provide insights into potential mechanisms, the associations between CHIP and inflammatory markers were also determined. RESULTS: In total, 47 (9.4%) patients with CTEPH carried at least 1 CHIP mutation at a variant allele frequency of ≥2%. The most common mutations were in DNMT3A, TET2, RUNX1, and ASXL1. During follow-up (mean, 55 months), deaths occurred in 22 (46.8%) and 104 (23.0%) patients in the CHIP and non-CHIP groups, respectively (P<0.001, log-rank test). The association of CHIP with mortality remained robust in the fully adjusted model (hazard ratio, 2.190 [95% CI, 1.257-3.816]; P=0.006). Moreover, patients with CHIP mutations showed higher circulating interleukin-1ß and interleukin-6 and lower interleukin-4 and IgG galactosylation levels. CONCLUSIONS: This is the first study to show that CHIP mutations occurred in 9.4% of patients with CTEPH are associated with a severe inflammatory state and confer a poorer prognosis in long-term follow-up.

Nrf1 is not a direct target gene of SREBP1, albeit both are integrated into the rapamycin-responsive regulatory network in human hepatoma cells.

The essential role of protein degradation by ubiquitin-proteasome system is exerted primarily for maintaining cellular protein homeostasis. The transcriptional activation of proteasomal genes by mTORC1 signaling depends on Nrf1, but whether this process is directly via SREBP1 remains elusive. In this study, our experiment evidence revealed that Nrf1 is not a direct target of SREBP1, although both are involved in the rapamycin-responsive regulatory networks. Closely scrutinizing two distinct transcriptomic datasets unraveled no significant changes in transcriptional expression of Nrf1 and almost all proteasomal subunits in either siSREBP2-silencing cells or SREBP1-∕-MEFs, when compared to equivalent controls. However, distinct upstream signaling to Nrf1 dislocation by p97 and its processing by DDI1/2, along with downstream proteasomal expression, may be monitored by mTOR signaling, to various certain extents, depending on distinct experimental settings in different types of cells. Our further evidence has been obtained from DDI1-∕-(DDI2insC) cells, demonstrating that putative effects of mTOR on the rapamycin-responsive signaling to Nrf1 and proteasomes may also be executed partially through a DDI1/2-independent mechanism, albeit the detailed regulatory events remain to be determined.

Identification and optimization of peptide inhibitors to block VISTA/PSGL-1 interaction for cancer immunotherapy.

Developing new therapeutic agents for cancer immunotherapy is highly demanding due to the low response ratio of PD-1/PD-L1 blockade in cancer patients. Here, we discovered that the novel immune checkpoint VISTA is highly expressed on a variety of tumor-infiltrating immune cells, especially myeloid derived suppressor cells (MDSCs) and CD8+ T cells. Then, peptide C1 with binding affinity to VISTA was developed by phage displayed bio-panning technique, and its mutant peptide VS3 was obtained by molecular docking based mutation. Peptide VS3 could bind VISTA with high affinity and block its interaction with ligand PSGL-1 under acidic condition, and elicit anti-tumor activity in vivo. The peptide DVS3-Pal was further designed by d-amino acid substitution and fatty acid modification, which exhibited strong proteolytic stability and significant anti-tumor activity through enhancing CD8+ T cell function and decreasing MDSCs infiltration. This is the first study to develop peptides to block VISTA/PSGL-1 interaction, which could act as promising candidates for cancer immunotherapy.

Sirolimus can promote the disappearance of renal angiomyolipoma associated with tuberous sclerosis complex: a prospective cohort study.

BACKGROUND: Renal angiomyolipoma (RAML) is the most common kidney lesion in patients with tuberous sclerosis complex (TSC), affecting about 80% of patients. It is a benign tumor that grows over time, usually bilaterally, and can easily lead to kidney complications such as acute hemorrhage. Herein, we investigated the efficacy and safety of sirolimus in children with TSC-associated RAML and explored the factors affecting tumor disappearance under sirolimus treatment through subgroup analysis. METHODS: A prospective cohort study was conducted. Sirolimus was initiated at 1 mg/(m2 × day), and dose adjustments were made by a 2-week titration period to attain a trough blood concentration of 5-10 ng/mL. The disappearance of RAML in children after sirolimus treatment was observed, and Cox regression was used to screen the factors affecting tumor disappearance. RESULTS: One hundred and twenty-six patients who met the criteria were analyzed. After 3 months, 6 months, 12 months, and 24 months of follow-up, tumors disappeared in 18 (14.3%), 30 (23.8%), 39 (31.0%), and 42 (33.3%) children, respectively. Tumors disappeared in 50 (39.7%) children by the last visit of each individual, and 30 (60%) of them occurred within 6 months. The multivariate Cox regression analysis showed that patients with a smaller maximum tumor diameter at baseline had a higher tumor disappearance rate. Thirty-six (29%) patients had stomatitis during the entire treatment period, and no serious adverse reactions were observed. CONCLUSIONS: Sirolimus could promote the disappearance of TSC-related RAML. The disappearance rate was correlated with the maximum diameter at baseline, and the smaller the tumor was, the higher the disappearance rate. It is well tolerated in the treatment of RAML associated with TSC.