AStruct: detection of allele-specific RNA secondary structure in structuromic probing data.

BACKGROUND: Uncovering functional genetic variants from an allele-specific perspective is of paramount importance in advancing our understanding of gene regulation and genetic diseases. Recently, various allele-specific events, such as allele-specific gene expression, allele-specific methylation, and allele-specific binding, have been explored on a genome-wide scale due to the development of high-throughput sequencing methods. RNA secondary structure, which plays a crucial role in multiple RNA-associated processes like RNA modification, translation and splicing, has emerged as an essential focus of relevant research. However, tools to identify genetic variants associated with allele-specific RNA secondary structures are still lacking. RESULTS: Here, we develop a computational tool called 'AStruct' that enables us to detect allele-specific RNA secondary structure (ASRS) from RT-stop based structuromic probing data. AStruct shows robust performance in both simulated datasets and public icSHAPE datasets. We reveal that single nucleotide polymorphisms (SNPs) with higher AStruct scores are enriched in coding regions and tend to be functional. These SNPs are highly conservative, have the potential to disrupt sites involved in m6A modification or protein binding, and are frequently associated with disease. CONCLUSIONS: AStruct is a tool dedicated to invoke allele-specific RNA secondary structure events at heterozygous SNPs in RT-stop based structuromic probing data. It utilizes allelic variants, base pairing and RT-stop information under different cell conditions to detect dynamic and functional ASRS. Compared to sequence-based tools, AStruct considers dynamic cell conditions and outperforms in detecting functional variants. AStruct is implemented in JAVA and is freely accessible at: https://github.com/canceromics/AStruct .

Single-cell transcriptomic analysis deciphers heterogenous cancer stem-like cells in colorectal cancer and their organ-specific metastasis.

OBJECTIVE: Metastasis is the major cause of cancer death. However, what types of heterogenous cancer cells in primary tumour and how they metastasise to the target organs remain largely undiscovered. DESIGN: We performed single-cell RNA sequencing and spatial transcriptomic analysis in primary colorectal cancer (CRC) and metastases in the liver (lCRC) or ovary (oCRC). We also conducted immunofluorescence staining and functional experiments to examine the mechanism. RESULTS: Integrative analyses of epithelial cells reveal a stem-like cell cluster with high protein tyrosine phosphatase receptor type O (PTPRO) and achaete scute-like 2 (ASCL2) expression as the metastatic culprit. This cell cluster comprising distinct subpopulations shows distinct liver or ovary metastatic preference. Population 1 (P1) cells with high delta-like ligand 4 (DLL4) and MAF bZIP transcription factor A (MAFA) expression are enriched in primary CRC and oCRC, thus may be associated with ovarian metastasis. P3 cells having a similar expression pattern as cholangiocytes are found mainly in primary CRC and lCRC, presuming to be likely the culprits that specifically metastasise to the liver. Stem-like cells interacted with cancer-associated fibroblasts and endothelial cells via the DLL4-NOTCH signalling pathway to metastasise from primary CRC to the ovary. In the oCRC microenvironment, myofibroblasts provide cancer cells with glutamine and perform a metabolic reprogramming, which may be essential for cancer cells to localise and develop in the ovary. CONCLUSION: We uncover a mechanism for organ-specific CRC metastasis.

BioTreasury: a community-based repository enabling indexing and rating of bioinformatics tools.

The exponential growth of bioinformatics tools in recent years has posed challenges for scientists in selecting the most suitable one for their data analysis assignments. Therefore, to aid scientists in making informed choices, a community-based platform that indexes and rates bioinformatics tools is urgently needed. In this study, we introduce BioTreasury ( http://biotreasury.rjmart.cn ), an integrated community-based repository that provides an interactive platform for users and developers to share their experiences in various bioinformatics tools. BioTreasury offers a comprehensive collection of well-indexed bioinformatics software, tools, and databases, totaling over 10,000 entries. In the past two years, we have continuously improved and maintained BioTreasury, adding several exciting features, including creating structured homepages for every tool and user, a hierarchical category of bioinformatics tools and classifying tools using large language model (LLM). BioTreasury streamlines the tool submission process with intelligent auto-completion. Additionally, BioTreasury provides a wide range of social features, for example, enabling users to participate in interactive discussions, rate tools, build and share tool collections for the public. We believe BioTreasury can be a valuable resource and knowledge-sharing platform for the biomedical community. It empowers researchers to effectively discover and evaluate bioinformatics tools, fostering collaboration and advancing bioinformatics research.

FTO up-regulation induced by MYC suppresses tumour progression in Epstein-Barr virus-associated gastric cancer.

BACKGROUND: Epstein-Barr virus-associated gastric cancer (EBVaGC) is regarded as a distinct molecular subtype of GC, accounting for approximately 9% of all GC cases. Clinically, EBVaGC patients are found to have a significantly lower frequency of lymph node metastasis and better prognosis than uninfected individuals. RNA N6-methyladenosine (m6A) modification has an indispensable role in modulating tumour progression in various cancer types. However, its impact on EBVaGC remains unclear. METHODS: Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and m6A dot blot were conducted to compare the m6A modification levels between EBVaGC and EBV-negative GC (EBVnGC) cells. Western blot, real-time quantitative PCR (RT-qPCR) and immunohistochemistry were applied to explore the underlying mechanism of the reduced m6A modification in EBVaGC. The biological function of fat mass and obesity-associated protein (FTO) was determined in vivo and in vitro. The target genes of FTO were screened by MeRIP-seq, RT-qPCR and Western blot. The m6A binding proteins of target genes were verified by RNA pulldown and RNA immunoprecipitation assays. Chromatin immunoprecipitation and Luciferase report assays were performed to investigate the mechanism how EBV up-regulated FTO expression. RESULTS: M6A demethylase FTO was notably increased in EBVaGC, leading to a reduction in m6A modification, and higher FTO expression was associated with better clinical outcomes. Furthermore, FTO depressed EBVaGC cell metastasis and aggressiveness by reducing the expression of target gene AP-1 transcription factor subunit (FOS). Methylated FOS mRNA was specifically recognized by the m6A 'reader' insulin-like growth factor 2 mRNA binding protein 1/2 (IGF2BP1/2), which enhanced its transcripts stability. Moreover, MYC activated by EBV in EBVaGC elevated FTO expression by binding to a specific region of the FTO promoter. CONCLUSIONS: Mechanistically, our work uncovered a crucial suppressive role of FTO in EBVaGC metastasis and invasiveness via an m6A-FOS-IGF2BP1/2-dependent manner, suggesting a promising biomarker panel for GC metastatic prediction and therapy.

p53-responsive CMBL reprograms glucose metabolism and suppresses cancer development by destabilizing phosphofructokinase PFKP.

Aerobic glycolysis is critical for cancer progression and can be exploited in cancer therapy. Here, we report that the human carboxymethylenebutenolidase homolog (carboxymethylenebutenolidase-like [CMBL]) acts as a tumor suppressor by reprogramming glycolysis in colorectal cancer (CRC). The anti-cancer action of CMBL is mediated through its interactions with the E3 ubiquitin ligase TRIM25 and the glycolytic enzyme phosphofructokinase-1 platelet type (PFKP). Ectopic CMBL enhances TRIM25 binding to PFKP, leading to the ubiquitination and proteasomal degradation of PFKP. Interestingly, CMBL is transcriptionally activated by p53 in response to genotoxic stress, and p53 activation represses glycolysis by promoting PFKP degradation. Remarkably, CMBL deficiency, which impairs p53's ability to inhibit glycolysis, makes tumors more sensitive to a combination therapy involving the glycolysis inhibitor 2-deoxyglucose. Taken together, our study demonstrates that CMBL suppresses CRC growth by inhibiting glycolysis and suggests a potential combination strategy for the treatment of CMBL-deficient CRC.

Super-enhancer RNA m6A promotes local chromatin accessibility and oncogene transcription in pancreatic ductal adenocarcinoma.

The biological functions of noncoding RNA N6-methyladenosine (m6A) modification remain poorly understood. In the present study, we depict the landscape of super-enhancer RNA (seRNA) m6A modification in pancreatic ductal adenocarcinoma (PDAC) and reveal a regulatory axis of m6A seRNA, H3K4me3 modification, chromatin accessibility and oncogene transcription. We demonstrate the cofilin family protein CFL1, overexpressed in PDAC, as a METTL3 cofactor that helps seRNA m6A methylation formation. The increased seRNA m6As are recognized by the reader YTHDC2, which recruits H3K4 methyltransferase MLL1 to promote H3K4me3 modification cotranscriptionally. Super-enhancers with a high level of H3K4me3 augment chromatin accessibility and facilitate oncogene transcription. Collectively, these results shed light on a CFL1-METTL3-seRNA m6A-YTHDC2/MLL1 axis that plays a role in the epigenetic regulation of local chromatin state and gene expression, which strengthens our knowledge about the functions of super-enhancers and their transcripts.

CSTF2 mediated mRNA N6-methyladenosine modification drives pancreatic ductal adenocarcinoma m6A subtypes.

N6-methyladenosine (m6A) modification of gene transcripts plays critical roles in cancer. Here we report transcriptomic m6A profiling in 98 tissue samples from 65 individuals with pancreatic ductal adenocarcinoma (PDAC). We identify 17,996 m6A peaks with 195 hyper-methylated and 93 hypo-methylated in PDAC compared with adjacent normal tissues. The differential m6A modifications distinguish two PDAC subtypes with different prognosis outcomes. The formation of the two subtypes is driven by a newly identified m6A regulator CSTF2 that co-transcriptionally regulates m6A installation through slowing the RNA Pol II elongation rate during gene transcription. We find that most of the CSTF2-regulated m6As have positive effects on the RNA level of host genes, and CSTF2-regulated m6As are mainly recognized by IGF2BP2, an m6A reader that stabilizes mRNAs. These results provide a promising PDAC subtyping strategy and potential therapeutic targets for precision medicine of PDAC.

An immunogenic and oncogenic feature-based classification for chemotherapy plus PD-1 blockade in advanced esophageal squamous cell carcinoma.

Although chemotherapy plus PD-1 blockade (chemo+anti-PD-1) has become the standard first-line therapy for advanced esophageal squamous cell carcinoma (ESCC), reliable biomarkers for this regimen are lacking. Here we perform whole-exome sequencing on tumor samples from 486 patients of the JUPITER-06 study and develop a copy number alteration-corrected tumor mutational burden that depicts immunogenicity more precisely and predicts chemo+anti-PD-1 efficacy. We identify several other favorable immunogenic features (e.g., HLA-I/II diversity) and risk oncogenic alterations (e.g., PIK3CA and TET2 mutation) associated with chemo+anti-PD-1 efficacy. An esophageal cancer genome-based immuno-oncology classification (EGIC) scheme incorporating these immunogenic features and oncogenic alterations is established. Chemo+anti-PD-1 achieves significant survival improvements in EGIC1 (immunogenic feature-favorable and oncogenic alteration-negative) and EGIC2 (either immunogenic feature-favorable or oncogenic alteration-negative) subgroups, but not the EGIC3 subgroup (immunogenic feature-unfavorable and oncogenic alteration-positive). Thus, EGIC may guide future individualized treatment strategies and inform mechanistic biomarker research for chemo+anti-PD-1 treatment in patients with advanced ESCC.

Evolutionary route of nasopharyngeal carcinoma metastasis and its clinical significance.

It is critical to understand factors associated with nasopharyngeal carcinoma (NPC) metastasis. To track the evolutionary route of metastasis, here we perform an integrative genomic analysis of 163 matched blood and primary, regional lymph node metastasis and distant metastasis tumour samples, combined with single-cell RNA-seq on 11 samples from two patients. The mutation burden, gene mutation frequency, mutation signature, and copy number frequency are similar between metastatic tumours and primary and regional lymph node tumours. There are two distinct evolutionary routes of metastasis, including metastases evolved from regional lymph nodes (lymphatic route, 61.5%, 8/13) and from primary tumours (hematogenous route, 38.5%, 5/13). The hematogenous route is characterised by higher IFN-γ response gene expression and a higher fraction of exhausted CD8+ T cells. Based on a radiomics model, we find that the hematogenous group has significantly better progression-free survival and PD-1 immunotherapy response, while the lymphatic group has a better response to locoregional radiotherapy.

Aberrant JAK-STAT signaling-mediated chromatin remodeling impairs the sensitivity of NK/T-cell lymphoma to chidamide.

BACKGROUND: Natural killer/T-cell lymphoma (NKTL) is a rare type of aggressive and heterogeneous non-Hodgkin's lymphoma (NHL) with a poor prognosis and limited therapeutic options. Therefore, there is an urgent need to exploit potential novel therapeutic targets for the treatment of NKTL. Histone deacetylase (HDAC) inhibitor chidamide was recently approved for treating relapsed/refractory peripheral T-cell lymphoma (PTCL) patients. However, its therapeutic efficacy in NKTL remains unclear. METHODS: We performed a phase II clinical trial to evaluate the efficacy of chidamide in 28 relapsed/refractory NKTL patients. Integrative transcriptomic, chromatin profiling analysis and functional studies were performed to identify potential predictive biomarkers and unravel the mechanisms of resistance to chidamide. Immunohistochemistry (IHC) was used to validate the predictive biomarkers in tumors from the clinical trial. RESULTS: We demonstrated that chidamide is effective in treating relapsed/refractory NKTL patients, achieving an overall response and complete response rate of 39 and 18%, respectively. In vitro studies showed that hyperactivity of JAK-STAT signaling in NKTL cell lines was associated with the resistance to chidamide. Mechanistically, our results revealed that aberrant JAK-STAT signaling remodels the chromatin and confers resistance to chidamide. Subsequently, inhibition of JAK-STAT activity could overcome resistance to chidamide by reprogramming the chromatin from a resistant to sensitive state, leading to synergistic anti-tumor effect in vitro and in vivo. More importantly, our clinical data demonstrated that combinatorial therapy with chidamide and JAK inhibitor ruxolitinib is effective against chidamide-resistant NKTL. In addition, we identified TNFRSF8 (CD30), a downstream target of the JAK-STAT pathway, as a potential biomarker that could predict NKTL sensitivity to chidamide. CONCLUSIONS: Our study suggests that chidamide, in combination with JAK-STAT inhibitors, can be a novel targeted therapy in the standard of care for NKTL. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02878278. Registered 25 August 2016, https://clinicaltrials.gov/ct2/show/NCT02878278.

VSOLassoBag: a variable-selection oriented LASSO bagging algorithm for biomarker discovery in omic-based translational research.

Screening biomolecular markers from high-dimensional biological data is one of the long-standing tasks for biomedical translational research. With its advantages in both feature shrinkage and biological interpretability, Least Absolute Shrinkage and Selection Operator (LASSO) algorithm is one of the most popular methods for the scenarios of clinical biomarker development. However, in practice, applying LASSO on omics-based data with high dimensions and low-sample size may usually result in an excess number of predictive variables, leading to the overfitting of the model. Here, we present VSOLassoBag, a wrapped LASSO approach by integrating an ensemble learning strategy to help select efficient and stable variables with high confidence from omics-based data. Using a bagging strategy in combination with a parametric method or inflection point search method, VSOLassoBag can integrate and vote variables generated from multiple LASSO models to determine the optimal candidates. The application of VSOLassoBag on both simulation datasets and real-world datasets shows that the algorithm can effectively identify markers for either case-control binary classification or prognosis prediction. In addition, by comparing with multiple existing algorithms, VSOLassoBag shows a comparable performance under different scenarios while resulting in fewer features than others. In summary, VSOLassoBag, which is available at https://seqworld.com/VSOLassoBag/ under the GPL v3 license, provides an alternative strategy for selecting reliable biomarkers from high-dimensional omics data. For user's convenience, we implement VSOLassoBag as an R package that provides multithreading computing configurations.

RM2Target: a comprehensive database for targets of writers, erasers and readers of RNA modifications.

RNA modification is a dynamic and reversible process regulated by a series of writers, erasers and readers (WERs). Abnormal changes of WERs will disrupt the RNA modification homeostasis of their target genes, leading to the dysregulation of RNA metabolisms such as RNA stability and translation, and consequently to diseases such as cancer. A public repository hosting the regulatory relationships between WERs and their target genes will help in understanding the roles of RNA modifications in various physiological and pathological conditions. Previously, we developed a database named 'm6A2Target' to host targets of WERs in m6A, one of the most prevalent RNA modifications in eukaryotic cells. To host all RNA modification (RM)-related WER-target associations, we hereby present an updated database, named 'RM2Target' (http://rm2target.canceromics.org/). In this update, RM2Target encompasses 1 619 653 WER-target associations for nine RNA modifications in human and mouse, including m6A, m6Am, m5C, m5U, m1A, m7G, pseudouridine, 2'-O-Me and A-to-I. Extensive annotations of target genes are available in RM2Target, including but not limited to basic gene information, RNA modifications, RNA-RNA/RNA-protein interactions and related diseases. Altogether, we expect that RM2Target will facilitate further downstream functional and mechanistic studies in the field of RNA modification research.

dSCOPE: a software to detect sequences critical for liquid-liquid phase separation.

Membrane-based cells are the fundamental structural and functional units of organisms, while evidences demonstrate that liquid-liquid phase separation (LLPS) is associated with the formation of membraneless organelles, such as P-bodies, nucleoli and stress granules. Many studies have been undertaken to explore the functions of protein phase separation (PS), but these studies lacked an effective tool to identify the sequence segments that critical for LLPS. In this study, we presented a novel software called dSCOPE (http://dscope.omicsbio.info) to predict the PS-driving regions. To develop the predictor, we curated experimentally identified sequence segments that can drive LLPS from published literature. Then sliding sequence window based physiological, biochemical, structural and coding features were integrated by random forest algorithm to perform prediction. Through rigorous evaluation, dSCOPE was demonstrated to achieve satisfactory performance. Furthermore, large-scale analysis of human proteome based on dSCOPE showed that the predicted PS-driving regions enriched various protein post-translational modifications and cancer mutations, and the proteins which contain predicted PS-driving regions enriched critical cellular signaling pathways. Taken together, dSCOPE precisely predicted the protein sequence segments critical for LLPS, with various helpful information visualized in the webserver to facilitate LLPS-related research.

TIGER: A Web Portal of Tumor Immunotherapy Gene Expression Resource.

Immunotherapy is a promising cancer treatment method; however, only a few patients benefit from it. The development of new immunotherapy strategies and effective biomarkers of response and resistance is urgently needed. Recently, high-throughput bulk and single-cell gene expression profiling technologies have generated valuable resources. However, these resources are not well organized and systematic analysis is difficult. Here, we present TIGER, a tumor immunotherapy gene expression resource, which contains bulk transcriptome data of 1508 tumor samples with clinical immunotherapy outcomes and 11,057 tumor/normal samples without clinical immunotherapy outcomes, as well as single-cell transcriptome data of 2,116,945 immune cells from 655 samples. TIGER provides many useful modules for analyzing collected and user-provided data. Using the resource in TIGER, we identified a tumor-enriched subset of CD4+ T cells. Patients with melanoma with a higher signature score of this subset have a significantly better response and survival under immunotherapy. We believe that TIGER will be helpful in understanding anti-tumor immunity mechanisms and discovering effective biomarkers. TIGER is freely accessible at http://tiger.canceromics.org/.

Whole-Exome Sequencing Among Chinese Patients With Hereditary Diffuse Gastric Cancer.

Importance: The E-cadherin gene, CDH1, and the α-E-catenin gene, CTNNA1, were previously identified as hereditary diffuse gastric cancer (HDGC) susceptibility genes, explaining 25% to 50% of HDGC cases. The genetic basis underlying disease susceptibility in the remaining 50% to 75% of patients with HDGC is still unknown. Objective: To assess the incidence rate of CDH1 germline alterations in HDGC, identify new susceptibility genes that can be used for screening of HDGC, and provide a genetic landscape for HDGC. Design, Setting, and Participants: This cohort study conducted retrospective whole-exome and targeted sequencing of 284 leukocyte samples and 186 paired tumor samples from Chinese patients with HDGC over a long follow-up period (median, 21.7 [range, 0.6-185.9] months). Among 10 431 patients diagnosed with gastric cancer between January 1, 2002, and August 31, 2018, 284 patients who met the criteria for HDGC were included. Data were analyzed from August 1 to 30, 2020. Main Outcomes and Measures: Incidence rate of CDH1 germline alterations, identification of new HDGC susceptibility genes, and genetic landscape of HDGC. Results: Among 284 Chinese patients, 161 (56.7%) were female, and the median age was 35 (range, 20-75) years. The frequency of CDH1 germline alterations was 2.8%, whereas the frequency of CDH1 somatic alterations was 25.3%. The genes with the highest incidence (>10%) of private germline alterations (including insertions and deletions) in the HDGC cohort were MUC4, ABCA13, ZNF469, FCGBP, IGFN1, RNF213, and SSPO, whereas previously reported germline alterations of CTNNA1, BRCA2, STK11, PRSS1, ATM, MSR1, PALB2, BRCA1, and RAD51C were observed at low frequencies (median, 4 [range, 1-12] cases). Furthermore, enrichment of the somatic variant signature of exposure to aflatoxin suggested potential interaction between genetics and environment in HDGC. Double-hit events in genes such as CACNA1D were observed, which suggested that these events might serve as important mechanisms for HDGC tumorigenesis. In addition, germline variants of FSIP2, HSPG2, and NCKAP5 and somatic alterations of FGFR3, ASPSCR1, CIC, DGCR8, and LZTR1 were associated with poor overall survival among patients with HDGC. Conclusions and Relevance: This study provided a genetic landscape for HDGC. The study's findings challenged the previously reported high germline alteration rate of CDH1 in HDGC and identified new potential susceptibility genes. Analyses of variant signatures and double-hit events revealed potentially important mechanisms for HDGC tumorigenesis. Findings from the present study may provide helpful information for further investigations of HDGC.

RAD21 amplification epigenetically suppresses interferon signaling to promote immune evasion in ovarian cancer.

Prevalent copy number alteration is the most prominent genetic characteristic associated with ovarian cancer (OV) development, but its role in immune evasion has not been fully elucidated. In this study, we identified RAD21, a key component of the cohesin complex, as a frequently amplified oncogene that could modulate immune response in OV. Through interrogating the RAD21-regulated transcriptional program, we found that RAD21 directly interacts with YAP/TEAD4 transcriptional corepressors and recruits the NuRD complex to suppress interferon (IFN) signaling. In multiple clinical cohorts, RAD21 overexpression is inversely correlated with IFN signature gene expression in OV. We further demonstrated in murine syngeneic tumor models that RAD21 ablation potentiated anti-PD-1 efficacy with increased intratumoral CD8+ T cell effector activity. Our study identifies a RAD21-YAP/TEAD4-NuRD corepressor complex in immune modulation, and thus provides a potential target and biomarker for precision immunotherapy in OV.

RNA m6A regulates transcription via DNA demethylation and chromatin accessibility.

Transcriptional regulation, which integrates chromatin accessibility, transcription factors and epigenetic modifications, is crucial for establishing and maintaining cell identity. The interplay between different epigenetic modifications and its contribution to transcriptional regulation remains elusive. Here, we show that METTL3-mediated RNA N6-methyladenosine (m6A) formation leads to DNA demethylation in nearby genomic loci in normal and cancer cells, which is mediated by the interaction between m6A reader FXR1 and DNA 5-methylcytosine dioxygenase TET1. Upon recognizing RNA m6A, FXR1 recruits TET1 to genomic loci to demethylate DNA, leading to reprogrammed chromatin accessibility and gene transcription. Therefore, we have characterized a regulatory mechanism of chromatin accessibility and gene transcription mediated by RNA m6A formation coupled with DNA demethylation, highlighting the importance of the crosstalk between RNA m6A and DNA modification in physiologic and pathogenic process.

Advances in detecting N6-methyladenosine modification in circRNAs.

Circular RNAs (circRNAs) are a class of noncoding RNAs with covalently single-stranded closed loop structures derived from back-splicing event of linear precursor mRNAs (pre-mRNAs). N6-methyladenosine (m6A), the most abundant epigenetic modification in eukaryotic RNAs, has been shown to play a crucial role in regulating the fate and biological function of circRNAs, and thus affecting various physiological and pathological processes. Accurate identification of m6A modification in circRNAs is an essential step to fully elucidate the crosstalk between m6A and circRNAs. In recent years, the rapid development of high-throughput sequencing technology and bioinformatic methodology has propelled the establishment of a multitude of approaches to detect circRNAs and m6A modification, including in vitro-based and in silico methods. Based on this, the research community has started on a new journey to develop methods for identification of m6A modification in circRNAs. In this review, we provide a comprehensive review and evaluation of the existing methods responsible for detecting circRNAs, m6A modification, and especially, m6A modification in circRNAs, which mainly focused on those developed based on high-throughput technologies and methodology of bioinformatics. This handy reference can help researchers figure out towards which direction this field will go.

Comprehensive Evaluation of the m6A Regulator Prognostic Risk Score in the Prediction of Immunotherapy Response in Clear Cell Renal Cell Carcinoma.

Background: Clear cell renal cell carcinoma (ccRCC) is known for its high drug resistance. The tumor-immune crosstalk mediated by the epigenetic regulation of N6-methyladenosine (m6A) modification has been demonstrated in recent studies. Therefore, m6A modification-mediated immune cell infiltration characteristics may be helpful to guide immunotherapy for ccRCC. Methods: This study comprehensively analyzed m6A modifications using the clinical parameters, single-cell RNA sequencing data, and bulk RNA sequencing data from the TCGA-ccRC cohort and 13 external validation cohorts. A series of bioinformatic approaches were applied to construct an m6A regulator prognostic risk score (MRPRS) to predict survival and immunotherapy response in ccRCC patients. Immunological characteristics, enriched pathways, and mutation were evaluated in high- and low-MRPRS groups. Results: The expressional alteration landscape of m6A regulators was profiled in ccRCC cell clusters and tissue. The 8 regulator genes with minimal lambda were integrated to build an MRPRS, and it was positively correlated with immunotherapeutic response in extent validation cohorts. The clinicopathological features and immune infiltration characteristics could be distinguished by the high- and low-MRPRS. Moreover, the MRPRS-mediated mutation pattern has an enhanced response to immune checkpoint blockade in the ccRCC and pan-cancer cohorts. Conclusions: The proposed MRPRS is a promising biomarker to predict clinical outcomes and therapeutic responses in ccRCC patients.