Identification of somatic mutations in non-small cell lung carcinomas using whole-exome sequencing

Machine learning-based prognostic model of lactylation-related genes for predicting prognosis and immune infiltration in patients with lung adenocarcinoma

BACKGROUND

Histone lactylation is a novel epigenetic modification that is involved in a variety of critical biological regulations. However, the role of lactylation-related genes in lung adenocarcinoma has yet to be investigated.

METHODS

RNA-seq data and clinical information of LUAD were downloaded from TCGA and GEO datasets. Unsupervised consistent cluster analysis was performed to identify differentially expressed genes (DEGs) between the two clusters, and risk prediction models were constructed by Cox regression analysis and LASSO analysis. Kaplan-Meier (KM) survival analysis, ROC curves and nomograms were used to validate the accuracy of the models. We also explored the differences in risk scores in terms of immune cell infiltration, immune cell function, TMB, TIDE, and anticancer drug sensitivity. In addition, single-cell clustering and trajectory analysis were performed to further understand the significance of lactylation-related genes. We further analyzed lactate content and glucose uptake in lung adenocarcinoma cells and tissues. Changes in LUAD cell function after knockdown of lactate dehydrogenase (LDHA) by CCK-8, colony formation and transwell assays. Finally, we analyzed the expression of KRT81 in LUAD tissues and cell lines using qRT-PCR, WB, and IHC. Changes in KRT81 function in LUAD cells were detected by CCK-8, colony formation, wound healing, transwell, and flow cytometry. A nude mouse xenograft model and a KrasLSL-G12D in situ lung adenocarcinoma mouse model were used to elucidate the role of KRT81 in LUAD.

RESULTS

After identifying 26 lactylation-associated DEGs, we constructed 10 lactylation-associated lung adenocarcinoma prognostic models with prognostic value for LUAD patients. A high score indicates a poor prognosis. There were significant differences between the high-risk and low-risk groups in the phenotypes of immune cell infiltration rate, immune cell function, gene mutation frequency, and anticancer drug sensitivity. TMB and TIDE scores were higher in high-risk score patients than in low-risk score patients. MS4A1 was predominantly expressed in B-cell clusters and was identified to play a key role in B-cell differentiation. We further found that lactate content was abnormally elevated in lung adenocarcinoma cells and cancer tissues, and glucose uptake by lung adenocarcinoma cells was significantly increased. Down-regulation of LDHA inhibits tumor cell proliferation, migration and invasion. Finally, we verified that the model gene KRT81 is highly expressed in LUAD tissues and cell lines. Knockdown of KRT81 inhibited cell proliferation, migration, and invasion, leading to cell cycle arrest in the G0/G1 phase and increased apoptosis. KRT81 may play a tumorigenic role in LUAD through the EMT and PI3K/AKT pathways. In vivo, KRT81 knockdown inhibited tumor growth.

CONCLUSION

We successfully constructed a new prognostic model for lactylation-related genes. Lactate content and glucose uptake are significantly higher in lung adenocarcinoma cells and cancer tissues. In addition, KRT81 was validated at cellular and animal levels as a possible new target for the treatment of LUAD, and this study provides a new perspective for the individualized treatment of LUAD.

Zearalenone promotes endometrial cancer cell migration and invasion via activation of estrogen receptor-mediated Rho/ROCK/PMLC signaling pathway

Zearalenone (ZEA), has emerged as a potential endocrine-disrupting chemical (EDC). Previous results show ZEA effects on endometrial stromal cell apoptosis, migration, and growth of endometriosis. Despite the reported presence of ZEA in Endometrial Cancer (EC) patient's blood and tissues, ZEA-induced EC promotion and its mechanism/s remain elusive. In this study, Ishikawa cells were used to investigate the ZEA effects on Ishikawa cell migration, invasion, and the underlying mechanism involved in these events. Ishikawa cells were exposed to low concentrations of ZEA (5, 25, and 125 nM) for 48 h, and morphological alterations, migration, invasion, markers associated with epithelial-mesenchymal transition (EMT), E-cadherin, Vimentin, RhoA/ROCK/PMLC pathway activation were analyzed. ZEA (25 nM) exposure caused morphological alterations like stress fiber, filopodia formation, loss of cell adhesion, and a significant increase in migration and invasive potential in extracellular matrix-coated porous membranes. Moreover, ZEA exposure also increases the Rho-GTPase activity and expression of pathway mediators, GEFH1, RhoA, ROCK1+2, CDC42, and PMLC/MLC. Furthermore, pre-treatment with specific pharmacological inhibitors for Estrogen receptor-alpha (ER-α) and ROCK attenuate the ZEA-induced stress fiber formation and altered expression of E-cadherin, Vimentin, and Rho/ROCK/PMLC pathway mediators. These findings suggest that Rho/ROCK/PMLC signaling pathways are involved in ZEA-induced Ishikawa cell migration and invasion.

Deciphering the Impact of Rare Missense Variants in EGFR-TKI-Resistant Non-Small-Cell Lung Cancer through Whole Exome Sequencing: A Computational Approach

Targeted therapy revolutionizes the treatment of non-small-cell lung cancer (NSCLC), harboring molecular change. Epidermal growth factor receptor(EGFR) mutations play a crucial role in the development of NSCLC, serving as a pivotal factor in its pathogenesis. We elucidated the mechanisms of resistance and potential therapeutic strategies in NSCLC resistant to the EGFR-tyrosine kinase inhibitor (EGFR-TKI). This is achieved by identifying rare missense variants through whole exome sequencing (WES). The goal is to enhance our understanding, identify biomarkers, and lay the groundwork for targeted interventions, thereby offering hope for an improved NSCLC treatment landscape. We conducted WES analysis on 16 NSCLC samples with EGFR-TKI-resistant NSCLC obtained from SRA-NCBI (PRJEB50602) to reveal genomic profiles within the EGFR-TKI. Our findings showed that 48% of the variants were missense, and after filtering with the Ensembl variant effect predictor, 53 rare missense variants in 23 genes were identified as highly deleterious. Further examination using pathogenic tools like PredictSNP revealed 12 deleterious rare missense variants in 7 genes: ZNF717, PSPH, ESRRA, SEMA3G, PTPN7, CAVIN4, and MYBBP1A. Molecular dynamics simulation (MDS) suggested that the L385P variant alters the structural flexibility of ESRRA, potentially leading to unfolding of ERRα proteins. This could impact their function and alter ERRα expression. These insights from MDS enhance our understanding of the structural and dynamic consequences of the L385P ESRRA variant and provide valuable implications for subsequent therapeutic considerations and targeted interventions.

Identification and validation of tryptophan metabolism-related lncRNAs in lung adenocarcinoma prognosis and immune response

BACKGROUND

Tryptophan (Trp) is an essential amino acid. Increasing evidence suggests that tryptophan metabolism plays a complex role in immune escape from Lung adenocarcinoma (LUAD). However, the role of long non-coding RNAs (lncRNAs) in tryptophan metabolism remains to be investigated.

METHODS

This study uses The Cancer Genome Atlas (TCGA)-LUAD dataset as the training cohort, and several datasets from the Gene Expression Omnibus (GEO) database are merged into the validation cohort. Genes related to tryptophan metabolism were identified from the Molecular Signatures Database (MSigDB) database and further screened for lncRNAs with Trp-related expression. Subsequently, a prognostic signature of lncRNAs related to tryptophan metabolism was constructed using Cox regression analysis, (Least absolute shrinkage and selection operator regression) and LASSO analysis. The predictive performance of this risk score was validated by Kaplan-Meier (KM) survival analysis, (receiver operating characteristic) ROC curves, and nomograms. We also explored the differences in immune cell infiltration, immune cell function, tumor mutational load (TMB), tumor immune dysfunction and exclusion (TIDE), and anticancer drug sensitivity between high- and low-risk groups. Finally, we used real-time fluorescence quantitative PCR, CCK-8, colony formation, wound healing, transwell, flow cytometry, and nude mouse xenotransplantation models to elucidate the role of ZNF8-ERVK3-1 in LUAD.

RESULTS

We constructed 16 tryptophan metabolism-associated lncRNA prognostic models in LUAD patients. The risk score could be used as an independent prognostic indicator for the prognosis of LUAD patients. Kaplan-Meier survival analysis, ROC curves, and risk maps validated the prognostic value of the risk score. The high-risk and low-risk groups showed significant differences in phenotypes, such as the percentage of immune cell infiltration, immune cell function, gene mutation frequency, and anticancer drug sensitivity. In addition, patients with high-risk scores had higher TMB and TIDE scores compared to patients with low-risk scores. Finally, we found that ZNF8-ERVK3-1 was highly expressed in LUAD tissues and cell lines. A series of in vitro experiments showed that knockdown of ZNF8-ERVK3-1 inhibited cell proliferation, migration, and invasion, leading to cell cycle arrest in the G0/G1 phase and increased apoptosis. In vivo experiments with xenografts have shown that knocking down ZNF8-ERVK3-1 can significantly inhibit tumor size and tumor proliferation.

CONCLUSION

We constructed a new prognostic model for tryptophan metabolism-related lncRNA. The risk score was closely associated with common clinical features such as immune cell infiltration, immune-related function, TMB, and anticancer drug sensitivity. Knockdown of ZNF8-ERVK3-1 inhibited LUAD cell proliferation, migration, invasion, and G0/G1 phase blockade and promoted apoptosis.

Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

Bi-allelic variants in DNAH3 cause male infertility with asthenoteratozoospermia in humans and mice

STUDY QUESTION

Are there other pathogenic genes for asthenoteratozoospermia (AT)?

SUMMARY ANSWER

DNAH3 is a novel candidate gene for AT in humans and mice.

WHAT IS KNOWN ALREADY

AT is a major cause of male infertility. Several genes underlying AT have been reported; however, the genetic aetiology remains unknown in a majority of affected men.

STUDY DESIGN SIZE DURATION

A total of 432 patients with AT were recruited in this study. DNAH3 mutations were identified by whole-exome sequencing (WES). Dnah3 knockout mice were generated using the genome editing tool. The morphology and motility of sperm from Dnah3 knockout mice were investigated. The entire study was conducted over 3 years.

PARTICIPANTS/MATERIALS SETTING METHODS

WES was performed on 432 infertile patients with AT. In addition, two lines of Dnah3 knockout mice were generated. Haematoxylin and eosin (H&E) staining, transmission electron microscopy (TEM), immunostaining, and computer-aided sperm analysis (CASA) were performed to investigate the morphology and motility of the spermatozoa. ICSI was used to overcome the infertility of one patient and of the Dnah3 knockout mice.

MAIN RESULTS AND THE ROLE OF CHANCE

DNAH3 biallelic variants were identified in three patients from three unrelated families. H&E staining revealed various morphological abnormalities in the flagella of sperm from the patients, and TEM and immunostaining further showed the loss of the central pair of microtubules, a dislocated mitochondrial sheath and fibrous sheath, as well as a partial absence of the inner dynein arms. In addition, the two Dnah3 knockout mouse lines demonstrated AT. One patient and the Dnah3 knockout mice showed good treatment outcomes after ICSI.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

This is a preliminary report suggesting that defects in DNAH3 can lead to asthenoteratozoospermia in humans and mice. The pathogenic mechanism needs to be further examined in a future study.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings show that DNAH3 is a novel candidate gene for AT in humans and mice and provide crucial insights into the biological underpinnings of this disorder. The findings may also be beneficial for counselling affected individuals.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by grants from National Natural Science Foundation of China (82201773, 82101961, 82171608, 32322017, 82071697, and 81971447), National Key Research and Development Program of China (2022YFC2702604), Scientific Research Foundation of the Health Committee of Hunan Province (B202301039323, B202301039518), Hunan Provincial Natural Science Foundation (2023JJ30716), the Medical Innovation Project of Fujian Province (2020-CXB-051), the Science and Technology Project of Fujian Province (2023D017), China Postdoctoral Science Foundation (2022M711119), and Guilin technology project for people's benefit (20180106-4-7). The authors declare no competing interests.

Whole‑exome sequencing reveals Lewis lung carcinoma is a hypermutated Kras/Nras-mutant cancer with extensive regional mutation clusters in its genome

Lewis lung carcinoma (LLC), as a widely used preclinical cancer model, has still not been genetically and genomically characterized. Here, we performed a whole-exome sequencing analysis on the LLC cell line to elucidate its molecular characteristics and etiologies. Our data showed that LLC originated from a male mouse belonging to C57BL/6L (a transitional strain between C57BL/6J and C57BL/6N) and contains substantial somatic SNV and InDel mutations (> 20,000). Extensive regional mutation clusters are present in its genome, which were caused mainly by the mutational processes underlying the SBS1, SBS5, SBS15, SBS17a, and SBS21 signatures during frequent structural rearrangements. Thirty three deleterious mutations are present in 30 cancer genes including Kras, Nras, Trp53, Dcc, and Cacna1d. Cdkn2a and Cdkn2b are biallelically deleted from the genome. Five pathways (RTK/RAS, p53, cell cycle, TGFB, and Hippo) are oncogenically deregulated or affected. The major mutational processes in LLC include chromosomal instability, exposure to metabolic mutagens, spontaneous 5-methylcytosine deamination, defective DNA mismatch repair, and reactive oxygen species. Our data also suggest that LLC is a lung cancer similar to human lung adenocarcinoma. This study lays a molecular basis for the more targeted application of LLC in preclinical research.

Comparison of the somatic genomic landscape between central- and peripheral-type non-small cell lung cancer

OBJECTIVE

Lung cancer is classified into central and peripheral types based on the anatomic location. The present study aimed to explore the distinct patterns of genomic alterations between central- and peripheral-type non-small cell lung cancers (NSCLCs) with negative driver genes and identify potential driver genes and biomarkers to improve therapy strategies for NSCLC.

METHODS

Whole-exome sequencing (WES) was performed with 182 tumor/control pairs of samples from 145 Chinese NSCLC patients without EGFR, ALK, or ROS1 alterations. Significantly mutated genes (SMGs) and somatic copy number alterations (SCNAs) were identified. Subsequently, tumor mutation burden (TMB), weighted genome integrity index (wGII), copy number alteration (CNA) burden, Shannon diversity index (SDI), intratumor heterogeneity (ITH), neoantigen load (NAL), and clonal variations were evaluated in central- and peripheral-type NSCLCs. Furthermore, mutational signature analysis and survival analysis were performed.

RESULTS

TP53 was the most frequently mutated gene in NSCLC and more frequently mutated in central-type NSCLC. Higher wGII, ITH, and SDI were found in central-type lung adenocarcinoma (LUAD) than in peripheral-type LUAD. The NAL of central-type lung squamous cell carcinoma (LUSC) with stage III/IV was significantly higher than that of peripheral-type LUSC. Mutational signature analysis revealed that SBS10b, SBS24, and ID7 were significantly different in central- and peripheral-type NSCLCs. Furthermore, central-type NSCLC was found to evolve at a higher level with fewer clones and more subclones, particularly in central-type LUSC. Survival analysis revealed that TMB, CNA burden, NAL, subclonal driver mutations, and subclonal mutations were negatively related to the overall survival (OS) and the progression-free survival (PFS) of central-type LUAD.

CONCLUSIONS

Central-type NSCLC tended to evolve at a higher level and might suggest a favorable response to immunotherapy. Our study also identified several potential driver genes and promising biomarkers for the prognosis and prediction of chemotherapy responses in NSCLC.

Variant Analysis of miRNA Regulatory Genes in 35 Sporadic Lung Carcinoma Tumors

Lung cancer is one of the cancer types with the highest mortality worldwide. The most frequently mutated genes known to be clinically important in lung cancers are EGFR, BRAF, and KRAS genes. Therefore, the therapeutic agents developed are directed against variants that cause over-activation of the EGFR-KRAS-BRAF-BRAF-MEK/ERK signalling pathway. However, different responses of patients to Tyrosine Kinase Inhibitors (TKIs) suggest that new prognostic biomarkers should be defined and epigenetic mechanisms may be related to this situation.

METHODS

In this study, sequence analyses of AGO2, DICER, and DROSHA genes involved in miRNA biogenesis and EGFR, KRAS, and BRAF genes were performed in 35 patients with sporadic lung cancer.

RESULTS

We found variations in genes involved in miRNA biogenesis that have not been previously reported in the literature. In addition, we found 4 different variants in the EGFR gene that have been described in the literature. In addition, a statistically significant association was found between the presence of mutations in at least one of the genes involved in miRNA biogenesis and metastasis (p:0.02).

CONCLUSIONS

In conclusion, genomic dysregulation of key miRNA biogenesis genes may be one of the possible reasons for the differential response of patients to therapeutic agents and the development of metastasis in EGFR wild type tumours.

Integrated Genomic Analysis of Primary Prostate Tumor Foci and Corresponding Lymph Node Metastases Identifies Mutations and Pathways Associated with Metastasis

Prostate cancer is a highly heterogeneous disease and mortality is mainly due to metastases but the initial steps of metastasis have not been well characterized. We have performed integrative whole exome sequencing and transcriptome analysis of primary prostate tumor foci and corresponding lymph node metastases (LNM) from 43 patients enrolled in clinical trial. We present evidence that, while there are some cases of clonally independent primary tumor foci, 87% of primary tumor foci and metastases are descended from a common ancestor. We demonstrate that genes related to oxidative phosphorylation are upregulated in LNM and in African-American patients relative to White patients. We further show that mutations in TP53, FLT4, EYA1, NCOR2, CSMD3, and PCDH15 are enriched in prostate cancer metastases. These findings were validated in a meta-analysis of 3929 primary tumors and 2721 metastases and reveal a pattern of molecular alterations underlying the pathology of metastatic prostate cancer. We show that LNM contain multiple subclones that are already present in primary tumor foci. We observed enrichment of mutations in several genes including understudied genes such as EYA1, CSMD3, FLT4, NCOR2, and PCDH15 and found that mutations in EYA1 and CSMD3 are associated with a poor outcome in prostate cancer.

A pan-cancer landscape of pathogenic somatic copy number variations

OBJECTIVE

Copy number variations (CNVs) play crucial roles in physiological and pathological processes, including cancer. However, the functional implications of somatic CNVs in tumor progression and evolution remain unclear. This study focuses on identifying CNV alterations with high pathogenic potential that drive and sustain tumorigenesis, distinguishing them from passenger alterations that accumulate during tumor growth. Our goal is to explore the variability of CNVs across different tumor types and infer their impact on tumor cell functions.

METHODS

Starting from 7352 copy number profiles across 33 different cancer types, we infer the pathogenicity of each CNV and perform both intra- and inter-tumor analyses to predict the functional impact of different genomic patterns. We evaluate the actionability of genes belonging to altered regions and we correlate the presence of pathogenic regions with genome instability patterns and patients' survival.

RESULTS

Our analysis uncovered large heterogeneity among different tumors suggesting in many cases distinct genetic drivers of tumorigenesis. Recurrent genomic alterations frequently coincide with dysfunctional homologous recombination pathways and negative regulation of the immune system. In certain tumors, the number of pathogenic CNVs emerged as a prognostic biomarker, highlighting their significance in cancer progression.

CONCLUSION

This study contributes to elucidate the functional impact of pathogenic CNVs in tumor progression and sheds light on their potential as prognostic markers in specific cancer types.

The significance of co-mutations in EGFR-mutated non-small cell lung cancer: Optimizing the efficacy of targeted therapies?

Non-small cell lung cancer (NSCLC) is the most common cause of cancer death worldwide. In non-squamous NSCLC, the identification of oncogenic drivers and the development of target-specific molecules led to remarkable progress in therapeutic strategies and overall survival over the last decade. Nevertheless, responses are limited by systematically acquired mechanisms of resistance early on after starting a targeted therapy. Moreover, mounting evidence has demonstrated that each oncogenic-driven cluster is actually heterogeneous in terms of molecular features, clinical behaviour, and sensitivity to targeted therapy. In this review, we aimed to examine the prognostic and predictive significance of oncogene-driven co-mutations, focusing mainly on EGFR and TP53. A narrative review was performed by searching MEDLINE databases for English articles published over the last decade (from January 2012 until November 2022). The bibliographies of key references were manually reviewed to select those eligible for the topic. The genetic landscape of EGFR-mutated NSCLC is more complicated than what is known so far. In particular, the occurrence of TP53 co-mutations stratify patients carrying EGFR mutations in terms of treatment response. The study provides a deeper understanding of the mechanisms underlying the variability of the genetic landscape of EGFR-mutated NSCLC and summarizes notably the clinical importance of TP53 co-mutations for an open avenue to more properly addressing the clinical decision-making in the near future.

PI3K/AKT/mTOR Dysregulation and Reprogramming Metabolic Pathways in Renal Cancer: Crosstalk with the VHL/HIF Axis

Renal cell carcinoma (RCC) represents 85-95% of kidney cancers and is the most frequent type of renal cancer in adult patients. It accounts for 3% of all cancer cases and is in 7th place among the most frequent histological types of cancer. Clear cell renal cell carcinoma (ccRCC), accounts for 75% of RCCs and has the most kidney cancer-related deaths. One-third of the patients with ccRCC develop metastases. Renal cancer presents cellular alterations in sugars, lipids, amino acids, and nucleic acid metabolism. RCC is characterized by several metabolic dysregulations including oxygen sensing (VHL/HIF pathway), glucose transporters (GLUT 1 and GLUT 4) energy sensing, and energy nutrient sensing cascade. Metabolic reprogramming represents an important characteristic of the cancer cells to survive in nutrient and oxygen-deprived environments, to proliferate and metastasize in different body sites. The phosphoinositide 3-kinase-AKT-mammalian target of the rapamycin (PI3K/AKT/mTOR) signaling pathway is usually dysregulated in various cancer types including renal cancer. This molecular pathway is frequently correlated with tumor growth and survival. The main aim of this review is to present renal cancer types, dysregulation of PI3K/AKT/mTOR signaling pathway members, crosstalk with VHL/HIF axis, and carbohydrates, lipids, and amino acid alterations.

Hepatoid adenocarcinoma-Clinicopathological features and molecular characteristics

Hepatoid adenocarcinoma (HAC) is a rare, malignant, extrahepatic tumor with histologic features similar to those of hepatocellular carcinoma. HAC is most often associated with elevated alpha-fetoprotein (AFP). HAC can occur in multiple organs, including the stomach, esophagus, colon, pancreas, lungs, and ovaries. HAC differs greatly from typical adenocarcinoma in terms of its biological aggression, poor prognosis, and clinicopathological characteristics. However, the mechanisms underlying its development and invasive metastasis remain unclear. The purpose of this review was to summarize the clinicopathological features, molecular traits, and molecular mechanisms driving the malignant phenotype of HAC, in order to support the clinical diagnosis and treatment of HAC.

Derivation of pancreatic acinar cell carcinoma cell line HS-1 as a patient-derived tumor organoid

Acinar cell carcinoma (ACC) of the pancreas is a malignant tumor of the exocrine cell lineage with a poor prognosis. Due to its rare incidence and technical difficulties, few authentic human cell lines are currently available, hampering detailed investigations of ACC. Therefore, we applied the organoid culture technique to various types of specimens, such as bile, biopsy, and resected tumor, obtained from a single ACC patient. Despite the initial propagation, none of these organoids achieved long-term proliferation or tolerated cryopreservation, confirming the challenging nature of establishing ACC cell lines. Nevertheless, the biopsy-derived early passage organoid developed subcutaneous tumors in immunodeficient mice. The xenograft tumor histologically resembled the original tumor and gave rise to infinitely propagating organoids with solid features and high levels of trypsin secretion. Moreover, the organoid stained positive for carboxylic ester hydrolase, a specific ACC marker, but negative for the duct cell marker CD133 and the endocrine lineage marker synaptophysin. Hence, we concluded the derivation of a novel ACC cell line of the pure exocrine lineage, designated HS-1. Genomic analysis revealed extensive copy number alterations and mutations in EP400 in the original tumor, which were enriched in primary organoids. HS-1 displayed homozygous deletion of CDKN2A, which might underlie xenograft formation from organoids. Although resistant to standard cytotoxic agents, the cell line was highly sensitive to the proteasome inhibitor bortezomib, as revealed by an in vitro drug screen and in vivo validation. In summary, we document a novel ACC cell line, which could be useful for ACC studies in the future.

Design, synthesis of novel benzimidazole derivatives as ENL inhibitors suppressing leukemia cells viability via downregulating the expression of MYC

Eleven-Nineteen-Leukemia Protein (ENL) containing YEATS domain, a potential drug target, has emerged as a reader of lysine acetylation. SGC-iMLLT bearing with benzimidazole scaffold was identified as an effective ENL inhibitor, but with weak activity against mixed-lineage leukemia (MLL)-rearranged cells proliferation. In this study, a series of compounds were designed and synthesized by structural optimization on SGC-iMLLT. All the compounds have been evaluated for their ENL inhibitory activities. The results showed that compounds 13, 23 and 28 are the most potential ones with the IC₅₀ values of 14.5 ± 3.0 nM, 10.7 ± 5.3 nM, and 15.4 ± 2.2 nM, respectively, similar with that of SGC-iMLLT. They could interact with ENL protein and strengthen its thermal stability in vitro. Among them, compound 28 with methyl phenanthridinone moiety replacement of indazole in SGC-iMLLT, exhibited significantly inhibitory activities towards MV4-11 and MOLM-13 cell lines with IC₅₀ values of 4.8 μM and 8.3 μM, respectively, exhibiting ∼7 folds and ∼9 folds more potent inhibition of cell growth than SGC-iMLLT. It could also increase the ENL thermal stability while SGC-iMLLT had no obvious effect on leukemia cells. Moreover, compound 28 could downregulate the expression of target gene MYC either alone or in combination with JQ-1 in cells, which was more effective than SGC-iMLLT. Besides, in vivo pharmacokinetic studies showed that the PK properties for compound 28 was much improved over that of SGC-iMLLT. These observations suggested compound 28 was a potential ligand for ENL-related MLL chemotherapy.

Immunogenomic analysis of human brain metastases reveals diverse immune landscapes across genetically distinct tumors

Brain metastases (BrMs) are the most common form of brain tumors in adults and frequently originate from lung and breast primary cancers. BrMs are associated with high mortality, emphasizing the need for more effective therapies. Genetic profiling of primary tumors is increasingly used as part of the effort to guide targeted therapies against BrMs, and immune-based strategies for the treatment of metastatic cancer are gaining momentum. However, the tumor immune microenvironment (TIME) of BrM is extremely heterogeneous, and whether specific genetic profiles are associated with distinct immune states remains unknown. Here, we perform an extensive characterization of the immunogenomic landscape of human BrMs by combining whole-exome/whole-genome sequencing, RNA sequencing of immune cell populations, flow cytometry, immunofluorescence staining, and tissue imaging analyses. This revealed unique TIME phenotypes in genetically distinct lung- and breast-BrMs, thereby enabling the development of personalized immunotherapies tailored by the genetic makeup of the tumors.

Lung Cancer Subtype Diagnosis by Fusing Image-Genomics Data and Hybrid Deep Networks

Accurate diagnosis of cancer subtypes is crucial for precise treatment, because different cancer subtypes are involved with different pathology and require different therapies. Although deep learning techniques have made great success in computer vision and other fields, they do not work well on Lung cancer subtype diagnosis, due to the distinction of slide images between different cancer subtypes is ambiguous. Furthermore, they often over-fit to high-dimensional genomics data with limited samples, and do not fuse the image and genomics data in a sensible way. In this paper, we propose a hybrid deep network based approach LungDIG for Lung cancer subtype Diagnosis by fusing Image-Genomics data. LungDIG first tiles the tissue slide image into small patches and extracts the patch-level features by fine-tuning an Inception-V3 model. Since the patches may contain some false positives in non-diagnostic regions, it further designs a patch-level feature combination strategy to integrate the extracted patch features and maintain the diversity between different cancer subtypes. At the same time, it extracts the genomics features from Copy Number Variation data by an attention based nonlinear extractor. Next, it fuses the image and genomics features by an attention based multilayer perceptron (MLP) to diagnose cancer subtype. Experiments on TCGA lung cancer data show that LungDIG can not only achieve higher accuracy for cancer subtype diagnosis than state-of-the-art methods, but also have a high authenticity and good interpretability.

Revealing the functions of clonal driver gene mutations in patients based on evolutionary dependencies

The clonal mutations in driver genes enable cells to gradually acquire growth advantage in tumor development. Therefore, revealing the functions of clonal driver gene mutations is important. Here, we proposed the method FCMP that considered evolutionary dependencies to analyze the functions of clonal driver gene mutations in a single patient. Applying our method to five cancer types from The Cancer Genome Atlas, we identified specific functions and common functions of clonal driver gene mutations. We found that the clonal driver gene mutations in the same patient played multiple functions. We also found that clonal mutations in the same driver gene performed different functions in different patients. These findings suggested that the clonal driver gene mutations showed strong tumor heterogeneity. In the pan-cancer analysis, the immune-related functions for clonal driver gene mutations were shared by multiple cancer types. In addition, clonal mutations in some driver genes predicted the survival of patients in cancers.

Comprehensive Exploration of M2 Macrophages and Its Related Genes for Predicting Clinical Outcomes and Drug Sensitivity in Lung Squamous Cell Carcinoma

Background

M2 macrophages play an important role in cancers. However, the role of M2 macrophages has not been clarified in lung squamous cell carcinoma.

Methods

All the open-accessed data were downloaded from The Cancer Genome Atlas database. All the analysis was performed in the R software. The CIBERSORT algorithm was utilized to quantify the immune cell infiltration in the tumor microenvironment. LASSO regression and multivariate Cox regression analysis were carried out for the creation of the prognostic model. Pathway enrichment analysis was performed using the single sample Gene Set Enrichment Analysis (ssGSEA) and clueGO algorithm.

Results

In our study, we comprehensively explored the role of M2 macrophages and its related genes in LUSC patients. We found that the patients with high M2 macrophage infiltration tend to have a worse prognosis. Also, some oncogenetic pathways were activated in the patients with high M2 macrophage infiltration. Further, a prognosis model based on six M2 macrophage-related genes was established, including TRIM58, VIPR2, CTNNA3, KIAA0408, CLEC4G, and MATN4, which showed a good prognosis prediction efficiency in both training and validation cohort. Pathway enrichment analysis showed that the pathway of allograft rejection, bile acid metabolism, coagulation, inflammatory response, IL6/JAK/STAT3 signaling, hedgehog signaling, peroxisome, and myogenesis were significantly activated in the high-risk patients. Based on the results of an investigation of immune infiltration, risk score was found to have a positive correlation with M2 macrophages and resting CD4+ memory T cells, but a negative correlation with follicular helper T cells, M1 macrophages, and Tregs. In addition, we discovered that patients in high-risk groups may respond better to immunotherapy than individuals in lower-risk groups. However, low-risk patients might be more sensitive to cisplatin.

Conclusions

Our model is a powerful tool to predict LUSC patient prognosis and could indicate the sensitivity of immunotherapy and chemotherapy.

Novel GIRlncRNA Signature for Predicting the Clinical Outcome and Therapeutic Response in NSCLC

Background: Non–small cell lung cancer (NSCLC) is highly malignant with driver somatic mutations and genomic instability. Long non-coding RNAs (lncRNAs) play a vital role in regulating these two aspects. However, the identification of somatic mutation-derived, genomic instability-related lncRNAs (GIRlncRNAs) and their clinical significance in NSCLC remains largely unexplored.

Methods: Clinical information, gene mutation, and lncRNA expression data were extracted from TCGA database. GIRlncRNAs were screened by a mutator hypothesis-derived computational frame. Co-expression, GO, and KEGG enrichment analyses were performed to investigate the biological functions. Cox and LASSO regression analyses were performed to create a prognostic risk model based on the GIRlncRNA signature (GIRlncSig). The prediction efficiency of the model was evaluated by using correlation analyses with mutation, driver gene, immune microenvironment contexture, and therapeutic response. The prognostic performance of the model was evaluated by external datasets. A nomogram was established and validated in the testing set and TCGA dataset.

Results: A total of 1446 GIRlncRNAs were selected from the screen, and the established GIRlncSig was used to classify patients into high- and low-risk groups. Enrichment analyses showed that GIRlncRNAs were mainly associated with nucleic acid metabolism and DNA damage repair pathways. Cox analyses further identified 19 GIRlncRNAs to construct a GIRlncSig-based risk score model. According to Cox regression and stratification analyses, 14 risk lncRNAs (AC023824.3, AC013287.1, AP000829.1, LINC01611, AC097451.1, AC025419.1, AC079949.2, LINC01600, AC004862.1, AC021594.1, MYRF-AS1, LINC02434, LINC02412, and LINC00337) and five protective lncRNAs (LINC01067, AC012645.1, AL512604.3, AC008278.2, and AC089998.1) were considered powerful predictors. Analyses of the model showed that these GIRlncRNAs were correlated with somatic mutation pattern, immune microenvironment infiltration, immunotherapeutic response, drug sensitivity, and survival of NSCLC patients. The GIRlncSig risk score model demonstrated good predictive performance (AUCs of ROC for 10-year survival was 0.69) and prognostic value in different NSCLC datasets. The nomogram comprising GIRlncSig and tumor stage exhibited improved robustness and feasibility for predicting NSCLC prognosis.

Conclusion: The newly identified GIRlncRNAs are powerful biomarkers for clinical outcome and prognosis of NSCLC. Our study highlights that the GIRlncSig-based score model may be a useful tool for risk stratification and management of NSCLC patients, which deserves further evaluation in future prospective studies.

Robust prognostic model based on immune infiltration-related genes and clinical information in ovarian cancer

Immune infiltration of ovarian cancer (OV) is a critical factor in determining patient's prognosis. Using data from TCGA and GTEx database combined with WGCNA and ESTIMATE methods, 46 genes related to OV occurrence and immune infiltration were identified. Lasso and multivariate Cox regression were applied to define a prognostic score (IGCI score) based on 3 immune genes and 3 types of clinical information. The IGCI score has been verified by K‐M curves, ROC curves and C‐index on test set. In test set, IGCI score (C‐index = 0.630) is significantly better than AJCC stage (C‐index = 0.541, p < 0.05) and CIN25 (C‐index = 0.571, p < 0.05). In addition, we identified key mutations to analyse prognosis of patients and the process related to immunity. Chi‐squared tests revealed that 6 mutations are significantly (p < 0.05) related to immune infiltration: BRCA1, ZNF462, VWF, RBAK, RB1 and ADGRV1. According to mutation survival analysis, we found 5 key mutations significantly related to patient prognosis (p < 0.05): CSMD3, FLG2, HMCN1, TOP2A and TRRAP. RB1 and CSMD3 mutations had small p‐value (p < 0.1) in both chi‐squared tests and survival analysis. The drug sensitivity analysis of key mutation showed when RB1 mutation occurs, the efficacy of six anti‐tumour drugs has changed significantly (p < 0.05).

In silico mutational analysis of ACE2 to check the susceptibility of lung cancer patients towards COVID-19

Being the second major cause of death worldwide, lung cancer poses a significant threat to the health of patients. This worsened during the era of pandemic since lung cancer is found to be more prone to SARS-CoV-2 infection. Many recent studies imply a high frequency of COVID-19 infection associated severe outcome. However, molecular studies are still lacking in this respect. Hence the current study is designed to investigate the binding affinities of ACE2 lung cancer mutants with the viral spike protein to find the susceptibility of respective mutants carrying patients in catching the virus. Quite interestingly, our study found lesser binding affinities of all the selected mutants thus implying that these cancer patients might be less affected by the virus than others. These results are opposed to the recent studies’ propositions and open new avenues for more in-depth studies.

Development of a 5-Gene Signature to Evaluate Lung Adenocarcinoma Prognosis Based on the Features of Cancer Stem Cells

Cancer stem cells (CSCs) can induce recurrence and chemotherapy resistance of lung adenocarcinoma (LUAD). Reliable markers identified based on CSC characteristic of LUAD may improve patients' chemotherapy response and prognosis. OCLR was used to calculate mRNA expression-based stemness index (mRNAsi) of LUAD patients' data in TCGA. Association analysis of mRNAsi was performed with clinical features, somatic mutation, and tumor immunity. A prognostic prediction model was established with LASSO Cox regression. Kaplan-Meier Plotter (KM-plotter) and time-dependent ROC were applied to assess signature performance. For LUAD, univariate and multivariate Cox analysis was performed to identify independent prognostic factors. LUAD tissues showed a noticeably higher mRNAsi in than nontumor tissues, and it showed significant differences in T, N, M, AJCC stages, and smoking history. The most frequently mutated gene was TP53, with a higher mRNAsi relating to more frequent mutation of TP53. The mRNAsi was significantly negatively correlated with immune score, stromal score, and ESTIMATE score in LUAD. The blue module was associated with mRNAsi. The 5-gene signature was confirmed as an independent indicator of LUAD prognosis that could promote personalized treatment of LUAD and accurately predict overall survival (OS) of LUAD patients.

Identifying Actionable Variants Using Capture-Based Targeted Sequencing in 563 Patients With Non-Small Cell Lung Carcinoma

Although the NSCLC diagnostic standards recommend the detection of driver gene mutation, comprehensive genomic profiling has not been used widely in clinical practice. As to the different mutation spectrum characteristics between populations, the research based on Chinese NSCLC cohort is very important for clinical practice. Therefore, we collected 563 surgical specimens from patients with non-small cell lung carcinoma and applied capture-based sequencing using eight-gene panel. We identified 556 variants, with 416 potentially actionable variants in 54.88% (309/563) patients. These single nucleotide variants, insertions and deletions were most commonly found in EGFR (55%), followed by ERBB2 (12%), KRAS (11%), PIK3CA (9%), MET (8%), BRAF (7%), DDR2 (2%), NRAS (0.3%). By using ten protein function prediction algorithms, we also identified 30 novel potentially pathogenic variants. Ninety-eight patients harbored EFGR exon 21 p.L858R mutation and the catalytic domain of the protein tyrosine kinase (PTKc) in EGFR is largely mutated. In addition, there were nine frequent pathogenic variants found in five or more patients. This data provides the potential molecular basis for directing the treatment of lung cancer.

Comparative assessment of genes driving cancer and somatic evolution in non-cancer tissues: an update of the Network of Cancer Genes (NCG) resource

Background

Genetic alterations of somatic cells can drive non-malignant clone formation and promote cancer initiation. However, the link between these processes remains unclear and hampers our understanding of tissue homeostasis and cancer development.

Results

Here, we collect a literature-based repertoire of 3355 well-known or predicted drivers of cancer and non-cancer somatic evolution in 122 cancer types and 12 non-cancer tissues. Mapping the alterations of these genes in 7953 pan-cancer samples reveals that, despite the large size, the known compendium of drivers is still incomplete and biased towards frequently occurring coding mutations. High overlap exists between drivers of cancer and non-cancer somatic evolution, although significant differences emerge in their recurrence. We confirm and expand the unique properties of drivers and identify a core of evolutionarily conserved and essential genes whose germline variation is strongly counter-selected. Somatic alteration in even one of these genes is sufficient to drive clonal expansion but not malignant transformation.

Conclusions

Our study offers a comprehensive overview of our current understanding of the genetic events initiating clone expansion and cancer revealing significant gaps and biases that still need to be addressed. The compendium of cancer and non-cancer somatic drivers, their literature support, and properties are accessible in the Network of Cancer Genes and Healthy Drivers resource at http://www.network-cancer-genes.org/.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13059-022-02607-z.

Identification of seven-gene marker to predict the survival of patients with lung adenocarcinoma using integrated multi-omics data analysis

Background

The mechanism of cancer occurrence and development could be understood with multi‐omics data analysis. Discovering genetic markers is highly necessary for predicting clinical outcome of lung adenocarcinoma (LUAD).

Methods

Clinical follow‐up information, copy number variation (CNV) data, single nucleotide polymorphism (SNP), and RNA‐Seq were acquired from The Cancer Genome Atlas (TCGA). To obtain robust biomarkers, prognostic‐related genes, genes with SNP variation, and copy number differential genes in the training set were selected and further subjected to feature selection using random forests. Finally, a gene‐based prediction model for LUAD was validated in validation datasets.

Results

The study filtered 2071 prognostic‐related genes and 230 genomic variants, 1878 copy deletions, and 438 significant mutations. 218 candidate genes were screened through integrating genomic variation genes and prognosis‐related genes. 7 characteristic genes (RHOV, CSMD3, FBN2, MAGEL2, SMIM4, BCKDHB, and GANC) were identified by random forest feature selection, and many genes were found to be tumor progression‐related. A 7‐gene signature constructed by Cox regression analysis was an independent prognostic factor for LUAD patients, and at the same time a risk factor in the test set, external validation set, and training set. Noticeably, the 5‐year AUC of survival in the validation set and training set was all ˃ 0.67. Similar results were obtained from multi‐omics validation datasets.

Conclusions

The study builds a novel 7‐gene signature as a prognostic marker for the survival prediction of patients with LUAD. The current findings provided a set of new prognostic and diagnostic biomarkers and therapeutic targets.

The Dawn of next generation DNA sequencing in myelodysplastic syndromes- experience from Pakistan

Background

Myelodysplastic syndromes (MDS) are clonal disorders of hematopoietic stem cells exhibiting ineffective hematopoiesis and tendency for transformation into acute myeloid leukemia (AML). The available karyotyping and fluorescent in situ hybridization provide limited information on molecular abnormalities for diagnosis/prognosis of MDS. Next generation DNA sequencing (NGS), providing deep insights into molecular mechanisms being involved in pathophysiology, was employed to study MDS in Pakistani cohort.

Patients and methods

It was a descriptive cross-sectional study carried out at National institute of blood diseases and bone marrow transplant from 2016 to 2019. Total of 22 cases of MDS were included. Complete blood counts, bone marrow assessment and cytogenetic analysis was done. Patients were classified according to revised WHO classification 2016 and IPSS score was applied for risk stratification. Baseline blood samples were subjected to analysis by NGS using a panel of 54 genes associated with myeloid malignancies.

Results

The median age of patients was 48.5 ± 9.19 years. The most common presenting complaint was weakness 10(45.45%). Cytogenetics analysis revealed abnormal karyotype in 10 (45.45%) patients. On NGS, 54 non-silent rare frequency somatic mutational events in 29 genes were observed (average of 3.82 (SD ± 2.08) mutations per patient), including mutations previously not observed in MDS or AML. Notably, two genes of cohesin complex, RAD21 and STAG2, and two tumor suppressor genes, CDKN2A and TP53, contained highest number of recurrent non-silent somatic mutations in the MDS. Strikingly, a missense somatic mutation p.M272Rof Rad21 was observed in 13 cases. Overall, non-silent somatic mutations in these four genes were observed in 21 of the 22 cases. The filtration with PharmGKB database highlighted a non-synonymous genetic variant rs1042522 [G > C] located in the TP53. Genotype GG and GC of this variant are associated with decreased response to cisplatin and paclitaxel chemotherapy. These two genotypes were found in 13 cases.

Conclusion

Sequencing studies suggest that numerous genetic variants are involved in the initiation of MDS and in the development of AML. In countries like Pakistan where financial reservation of patients makes the use of such analysis even more difficult when the availability of advanced techniques is already a prevailing issue, our study could be an initiating effort in adding important information to the local data. Further studies and large sample size are needed in future to enlighten molecular profiling and ultimately would be helpful to compare and contrast the molecular characteristics of Asian versus global population.

Two alternative cell line models for the study of multiorganic metastasis and immunotherapy in Lung Squamous Cell Carcinoma

There is a paucity of adequate mouse models and cell lines available to study lung squamous cell carcinoma (LUSC). We have generated and characterized two models of phenotypically different transplantable LUSC cell lines (UN-SCC679 and UN-SCC680) derived from an N-nitroso-tris-chloroethylurea (NTCU) chemically-induced mouse model in A/J mice. Furthermore, we genetically characterized and compared both LUSC cell lines by performing whole exome and RNA sequencing. These experiments revealed similar genetic and transcriptomic patterns that may correspond to the classical LUSC human subtype. In addition, we compared the immune landscape generated by both tumor cells lines in vivo and assessed their response to immune checkpoint inhibition. The differences between the two cell lines are a good model for the remarkable heterogeneity of human squamous cell carcinoma. Study of the metastatic potential of these models revealed that both cell lines represent the human LUSC organotropism to the brain, bones, liver and adrenal glands. In summary, we have generated a very valuable cell line tools for LUSC research that recapitulates the complexity of the human disease.

GDPLichi: a DNA Damage Repair-Related Gene Classifier for Predicting Lung Adenocarcinoma Immune Checkpoint Inhibitors Response

Lung cancer is one of the most common and mortal malignancies, usually with a poor prognosis in its advanced or recurrent stages. Recently, immune checkpoint inhibitors (ICIs) immunotherapy has revolutionized the treatment of human cancers including lung adenocarcinoma (LUAD), and significantly improved patients' prognoses. However, the prognostic and predictive outcomes differ because of tumor heterogeneity. Here, we present an effective method, GDPLichi (Genes of DNA damage repair to predict LUAD immune checkpoint inhibitors response), as the signature to predict the LUAD patient's response to the ICIs. GDPLichi utilized only 7 maker genes from 8 DDR pathways to construct the predictive model and classified LUAD patients into two subgroups: low- and high-risk groups. The high-risk group was featured by worse prognosis and decreased B cells, CD8+ T cells, CD8+ central memory T cells, hematopoietic stem cells (HSC), myeloid dendritic cells (MDC), and immune scores as compared to the low-risk group. However, our research also suggests that the high-risk group was more sensitive to ICIs, which might be explained by increased TMB, neoantigen, immune checkpoint molecules, and immune suppression genes' expression, but lower TIDE score as compared to the low-risk group. This conclusion was verified in three other LUAD cohort datasets (GSE30219, GSE31210, GSE50081).

Common mechanism of Citrus Grandis Exocarpium in treatment of chronic obstructive pulmonary disease and lung cancer

Objective

“Same treatment for different diseases” is a unique treatment strategy in traditional Chinese medicine. Two kinds of malignant respiratory diseases endanger human health-chronic obstructive pulmonary disease (COPD) and lung cancer. Citrus Grandis Exocarpium (Huajuhong in Chinese, HJH), a famous herbal, is always applied by Chinese medicine practitioners to dispersion the lung to resolve phlegm based on “syndrome differentiation and treatment” theory. However, the common mechanism for HJH’s treatment of COPD and lung cancer is not clear.

Methods

In this study, based on network pharmacology and molecular docking technology, the common mechanism of HJH in the treatment of COPD and lung cancer was studied. The active ingredients and related targets of HJH were integrated from TCMSP, BATMAN-TAM, STP, and Pubchem databases. The standard names of these targets were united by UniProt database. Targets of COPD and lung cancer were enriched through GeneCards, NCBI (Gene), Therapeutic Target Database, and DisGeNET (v7.0) databases. Then the intersection targets of HJH and diseases were obtained. The STRING network and the Cytoscape 3.7.2 were used to construct PPI network, the DAVID database was used to perform GO and KEGG analysis. Then Cytoscape 3.6.1 was used to build “ingredient-target-signal pathway” network. Finally, AutoDock 1.5.6 software was used to perform molecular docking of key proteins and molecules.

Results

Eleven active ingredients in HJH were obtained by searching the database, corresponding to 184 HJH-COPD-lung cancer targets intersection. The results of biological network analysis showed that naringenin, the active component in HJH, could mainly act on target proteins such as AKT1, EGFR. Then through positive regulation of vasoconstriction and other biological processes, naringenin could regulate estrogen signaling pathway, VEGF signaling pathway, HIF-1 signaling pathway, ErbB signaling pathway, PI3K-Akt signaling pathway to play an important role in the treatment of both COPD and lung cancer.

Conclusion

Network pharmacology was employed to systematically investigate the active ingredients and targets of HJH in treatment of COPD and lung cancer. And then, the common pharmacodynamic network of HJH for the two malignant respiratory diseases was firstly described. Furthermore, naringenin was proved to strongly bind with AKT1 and EGFR. It may provide the scientific basis for understanding the “Same treatment for different diseases” strategy in traditional Chinese medicine and inspirit subsequent drug discovery for COPD, lung cancer and other malignant lung diseases.

Complement inhibitor CSMD1 modulates epidermal growth factor receptor oncogenic signaling and sensitizes breast cancer cells to chemotherapy

BACKGROUND

Human CUB and Sushi multiple domains 1 (CSMD1) is a large membrane-bound tumor suppressor in breast cancer. The current study aimed to elucidate the molecular mechanism underlying the effect of CSMD1 in highly invasive triple negative breast cancer (TNBC).

METHODS

We examined the antitumor action of CSMD1 in three TNBC cell lines overexpressing CSMD1, MDA-MB-231, BT-20 and MDA-MB-486, in vitro using scanning electron microscopy, proteome array, qRT-PCR, immunoblotting, proximity ligation assay, ELISA, co-immunoprecipitation, immunofluorescence, tumorsphere formation assays and flow cytometric analysis. The mRNA expression pattern and clinical relevance of CSMD1 were evaluated in 3520 breast cancers from a modern population-based cohort.

RESULTS

CSMD1-expressing cells had distinct morphology, with reduced deposition of extracellular matrix components. We found altered expression of several cancer-related molecules, as well as diminished expression of signaling receptors including Epidermal Growth Factor Receptor (EGFR), in CSMD1-expressing cells compared to control cells. A direct interaction of CSMD1 and EGFR was identified, with the EGF-EGFR induced signaling cascade impeded in the presence of CSMD1. Accordingly, we detected increased  ubiquitination levels of EGFR upon activation in CSMD1-expressing cells, as well as increased degradation kinetics and chemosensitivity. Accordingly, CSMD1 expression rendered tumorspheres pretreated with gefitinib more sensitive to chemotherapy. In addition, higher mRNA levels of CSMD1 tend to be associated with better outcome of triple negative breast cancer patients treated with chemotherapy.

CONCLUSIONS

Our results indicate that CSMD1 cross-talks with the EGFR endosomal trafficking cascade in a way that renders highly invasive breast cancer cells sensitive to chemotherapy. Our study unravels one possible underlying molecular mechanism of CSMD1 tumor suppressor function and may provide novel avenues for design of better treatment.

Genomic and transcriptomic profiling of hepatoid adenocarcinoma of the stomach

Hepatoid adenocarcinoma of the stomach (HAS), a rare subtype of gastric cancer (GC), has a low incidence but a high mortality rate. Little is known about the molecular features of HAS. Here we applied whole-exome sequencing (WES) on 58 tumours and the matched normal controls from 54 HAS patients, transcriptome sequencing on 30 HAS tumours, and single-cell RNA sequencing (scRNA-seq) on one HAS tumour. Our results reveal that the adenocarcinomatous component and hepatocellular-like component of the same HAS tumour originate monoclonally, and HAS is likely to initiate from pluripotent precursor cells. HAS has high stemness and high methionine cycle activity compared to classical GC. Two genes in the methionine cycle, MAT2A, and AHCY are potential targets for HAS treatments. We provide the first integrative genomic profiles of HAS, which may facilitate its diagnosis, prognosis, and treatment.

The genomic landscape of 85 advanced neuroendocrine neoplasms reveals subtype-heterogeneity and potential therapeutic targets

Metastatic and locally-advanced neuroendocrine neoplasms (aNEN) form clinically and genetically heterogeneous malignancies, characterized by distinct prognoses based upon primary tumor localization, functionality, grade, proliferation index and diverse outcomes to treatment. Here, we report the mutational landscape of 85 whole-genome sequenced aNEN. This landscape reveals distinct genomic subpopulations of aNEN based on primary localization and differentiation grade; we observe relatively high tumor mutational burdens (TMB) in neuroendocrine carcinoma (average 5.45 somatic mutations per megabase) with TP53, KRAS, RB1, CSMD3, APC, CSMD1, LRATD2, TRRAP and MYC as major drivers versus an overall low TMB in neuroendocrine tumors (1.09). Furthermore, we observe distinct drivers which are enriched in somatic aberrations in pancreatic (MEN1, ATRX, DAXX, DMD and CREBBP) and midgut-derived neuroendocrine tumors (CDKN1B). Finally, 49% of aNEN patients reveal potential therapeutic targets based upon actionable (and responsive) somatic aberrations within their genome; potentially directing improvements in aNEN treatment strategies.

Whole-exome sequencing of alpha-fetoprotein producing gastric carcinoma reveals genomic profile and therapeutic targets

Alpha-fetoprotein producing gastric carcinoma (AFPGC) is a rare and aggressive subtype of gastric cancer. However, little is known about the genomic features of this disease. We perform whole-exome sequencing analysis of AFPGC, and identify 34 significantly mutated genes. Somatic copy number alterations analysis reveals several significant focal amplifications (e.g. 19q12, 17q12) and focal deletions (e.g. 1p36.11, 9p21.3), and some of these negatively affect the patient prognosis. Comparative analyses reveal that AFPGC has distinct genomic features from gastric cancer of The Cancer Genome Atlas as well as four molecular subtypes. Several frequently altered genes with potential as therapeutic targets are identified in AFPGC. Further analysis reveals that AFPGC with amplification of CCNE1 at 19q12 and/or ERBB2 at 17q12 show poorer survival and more aggressive. Subsequently, based on our established patient-derived xenograft models for AFPGC, translational research is performed and the therapeutic value of targeting CCNE1 and ERBB2 is validated. In this work, we provide an understanding of genomic characteristics of AFPGC and propose a platform to explore and validate the genome-guided personalized treatment for this disease.

The MLL3/4 H3K4 methyltransferase complex in establishing an active enhancer landscape

Enhancers are cis-regulatory elements that play essential roles in tissue-specific gene expression during development. Enhancer function in the expression of developmental genes requires precise regulation, while deregulation of enhancer function could be the main cause of tissue-specific cancer development. MLL3/KMT2C and MLL4/KMT2D are two paralogous histone modifiers that belong to the SET1/MLL (also named COMPASS) family of lysine methyltransferases and play critical roles in enhancer-regulated gene activation. Importantly, large-scale DNA sequencing studies have revealed that they are amongst the most frequently mutated genes associated with human cancers. MLL3 and MLL4 form identical multi-protein complexes for modifying mono-methylation of histone H3 lysine 4 (H3K4) at enhancers, which together with the p300/CBP-mediated H3K27 acetylation can generate an active enhancer landscape for long-range target gene activation. Recent studies have provided a better understanding of the possible mechanisms underlying the roles of MLL3/MLL4 complexes in enhancer regulation. Moreover, accumulating studies offer new insights into our knowledge of the potential role of MLL3/MLL4 in cancer development. In this review, we summarize recent evidence on the molecular mechanisms of MLL3/MLL4 in the regulation of active enhancer landscape and long-range gene expression, and discuss their clinical implications in human cancers.

Next-generation sequencing reveals novel mutations in a collision tumor of glioblastoma and meningioma

Primary intracranial collision tumors are rare in patients without predisposing factors. We report such a case in a 42-year-old female who presented with headaches and altered mental status. Imaging revealed a single heterogeneous, rim-enhancing lesion in the left parieto-occipital periventricular region, involving the corpus callosum. Stereotactic biopsy demonstrated glioblastoma. Subsequent tumor resection showed histologic evidence of glioblastoma and meningioma. Next-generation sequencing was performed on both tumor components. The glioblastoma exhibited a CDKN2A homozygous deletion and novel missense mutations in TAF1L and CSMD3, while no definitive genetic alterations were identified in the meningioma. Next-generation sequencing may yield insight into molecular drivers of intracranial collision tumors and aid in identifying future therapeutic targets.

Next-generation sequencing (NGS) reveals novel mutations in a collision tumor of GBM and meningioma. NGS has the potential to yield insight into molecular drivers of intracranial tumors and identify therapeutic targets.

Identification of genetic variations associated with drug resistance in non-small cell lung cancer patients undergoing systemic treatment

Non-small cell lung cancer (NSCLC) is characterized by relatively rapid response to systemic treatments yet inevitable resistance and predisposed to distant metastasis. We thus aimed at performing sequencing analysis to determine genomic events and underlying mechanisms concerning drug resistance in NSCLC. We performed targeted sequencing of 40 medication-relevant genes on plasma samples from 98 NSCLC patients and analyzed impact of genetic alterations on clinical presentation as well as response to systemic treatments. Profiling of multi-omics data from 1024 NSCLC tissues in public datasets was carried out for comparison and validation of identified molecular events implicated in resistance. A genetic association of CYP2D6 deletion with drug resistance was identified through circulating tumor DNA (ctDNA) profiling and response assessment. FCGR3A amplification was potentially involved in resistance to EGFR inhibitors. We further verified our findings in tissue samples and focused on potential resistance mechanisms, which uncovered that depleted CYP2D6 affected a set of genes involved in EMT, oncogenic signaling as well as inflammatory pathways. Tumor microenvironment analysis revealed that NSCLC with CYP2D6 loss manifested increased levels of immunomodulatory gene expressions, PD-L1 expression, relatively high mutational burden and lymphocyte infiltration. DNA methylation alterations were also found to be correlated with mRNA expressions and copy numbers of CYP2D6. Finally, MEK inhibitors were identified by CMap as the prospective therapeutic drugs for CYP2D6 deletion. These analyses identified novel resistance mechanisms to systemic NSCLC treatments and had significant implications for the development of new treatment strategies.

Inhibition of Tumor VEGFR2 Induces Serine 897 EphA2-Dependent Tumor Cell Invasion and Metastasis in NSCLC

Anti-angiogenic treatment targeting vascular endothelial growth factor (VEGF)-VEGFR2 signaling has shown limited efficacy in lung cancer patients. Here, we demonstrate that inhibition of VEGFR2 in tumor cells, expressed in ∼20% of non-squamous non-small cell lung cancer (NSCLC) patients, leads to a pro-invasive phenotype. Drug-induced inhibition of tumor VEGFR2 interferes with the formation of the EphA2/VEGFR2 heterocomplex, thereby allowing RSK to interact with Serine 897 of EphA2. Inhibition of RSK decreases phosphorylation of Serine 897 EphA2. Selective genetic modeling of Serine 897 of EphA2 or inhibition of EphA2 abrogates the formation of metastases in vivo upon VEGFR2 inhibition. In summary, these findings demonstrate that VEGFR2-targeted therapy conditions VEGFR2-positive NSCLC to Serine 897 EphA2-dependent aggressive tumor growth and metastasis. These data shed light on the molecular mechanisms explaining the limited efficacy of VEGFR2-targeted anti-angiogenic treatment in lung cancer patients.

Comprehensive molecular analysis of genomic profiles and PD-L1 expression in lung adenocarcinoma with a high-grade fetal adenocarcinoma component

Background

Fetal adenocarcinoma of the lung is a rare variant of lung adenocarcinoma and is subcategorized into low-grade and high-grade (H-FLAC) fetal adenocarcinoma. We previously reported poor prognosis in pulmonary adenocarcinomas with an H-FLAC component; however, the genetic abnormalities involved in H-FLAC remain unclear. Therefore, this study aimed to elucidate molecular abnormalities as potential therapeutic targets for H-FLACs.

Methods

We performed immunohistochemical analysis and comprehensive genetic analyses using whole-exome sequencing in 16 lung cancer samples with an H-FLAC component. DNA was extracted from formalin-fixed paraffin-embedded tissues after macrodissection of the H-FLAC component.

Results

Cancer-related mutations were identified in TP53 (7/16 cases), KMT2C (6/16 cases), KRAS (4/16 cases), NF1 (3/16 cases), STK11 (3/16 cases), CTNNB1 (2/16 cases), and EGFR (1/16 cases). A high tumor mutation burden of ≥10 mutations per megabase was observed in 3/16 cases. A high microsatellite instability was not detected in any case. Based on the cosine similarity with the Catalogue of Somatic Mutations in Cancer mutational signatures, H-FLACs were hierarchically clustered into three types: common adenocarcinoma-like (five cases), surfactant-deficient (ten cases), and signatures 2 and 13-related (one case). All common adenocarcinoma-like cases presented thyroid transcription factor-1 (TTF-1) expression, whereas surfactant-deficient cases often presented loss of TTF-1 and surfactant protein expression and included cases with mutations in the surfactant system genes NKX2-1 and SFTPC. H-FLACs displayed low programmed death ligand-1 (PD-L1) expression (1–49% of tumor cells) in 5/16 cases, and no case displayed high PD-L1 expression (≥50% of tumor cells).

Conclusions

This study indicates that lung cancers with an H-FLAC component rarely harbor currently targetable driver gene mutations for lung cancer but display a high frequency of KMT2C mutations. The microsatellite instability, tumor mutation burden, and PD-L1 expression status suggest a poor response to immune checkpoint therapy.

Comprehensive Profiling of Genomic and Transcriptomic Differences between Risk Groups of Lung Adenocarcinoma and Lung Squamous Cell Carcinoma

Lung cancer is the second most frequently diagnosed cancer type and responsible for the highest number of cancer deaths worldwide. Lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) are subtypes of non-small-cell lung cancer which has the highest frequency of lung cancer cases. We aimed to analyze genomic and transcriptomic variations including simple nucleotide variations (SNVs), copy number variations (CNVs) and differential expressed genes (DEGs) in order to find key genes and pathways for diagnostic and prognostic prediction for lung adenocarcinoma and lung squamous cell carcinoma. We performed a univariate Cox model and then lasso-regularized Cox model with leave-one-out cross-validation using The Cancer Genome Atlas (TCGA) gene expression data in tumor samples. We generated 35- and 33-gene signatures for prognostic risk prediction based on the overall survival time of the patients with LUAD and LUSC, respectively. When we clustered patients into high- and low-risk groups, the survival analysis showed highly significant results with high prediction power for both training and test datasets. Then, we characterized the differences including significant SNVs, CNVs, DEGs, active subnetworks, and the pathways. We described the results for the risk groups and cancer subtypes separately to identify specific genomic alterations between both high-risk groups and cancer subtypes. Both LUAD and LUSC high-risk groups have more downregulated immune pathways and upregulated metabolic pathways. On the other hand, low-risk groups have both up- and downregulated genes on cancer-related pathways. Both LUAD and LUSC have important gene alterations such as CDKN2A and CDKN2B deletions with different frequencies. SOX2 amplification occurs in LUSC and PSMD4 amplification in LUAD. EGFR and KRAS mutations are mutually exclusive in LUAD samples. EGFR, MGA, SMARCA4, ATM, RBM10, and KDM5C genes are mutated only in LUAD but not in LUSC. CDKN2A, PTEN, and HRAS genes are mutated only in LUSC samples. The low-risk groups of both LUAD and LUSC tend to have a higher number of SNVs, CNVs, and DEGs. The signature genes and altered genes have the potential to be used as diagnostic and prognostic biomarkers for personalized oncology.

Unique genomic features and prognostic value of COSMIC mutational signature 4 in lung adenocarcinoma and lung squamous cell carcinoma

Background

Analysis of mutational signatures is becoming routine in cancer genomics, with implications for pathogenesis, classification, and prognosis. Among the signatures cataloged at COSMIC, mutational signature 4 has been linked to smoking. However, the distribution of signature 4 in Chinese lung cancer patients has not been evaluated, and its clinical value has not been evaluated. Here we survey mutational signatures in Chinese lung cancer patients and explore the relationship between signature 4 and other genomic features in the patients.

Methods

We extracted mutational signatures from whole-exome sequencing data of Chinese non-small cell lung cancer patients. The data included 401 lung adenocarcinoma (LUAD) and 92 squamous cell carcinoma (LUSC). We then performed statistical analysis to search for genomic and clinical features that can be linked to mutation signatures.

Results

We found signature 4 is the most frequent mutational signature in LUSC and the second most frequent in LUAD. Fifty-six LUAD and thirty-five LUSC patients were named with high signature 4 similarities (cosine similarity >0.7). These patients have shorter survival and higher tumor mutational burden comparing to those with low signature 4 similarities. Dozens of genes with single nucleotide variation, index mutations, and copy number variations were differentially enriched in the patients with high signature 4 similarities. Among these genes, CSMD3, LRP1B, TP53, SYNE1, SLIT2, FGF4, and FGF19 are common in both LUADs and LUSCs with high signature 4 similarities, showing that these genes are tightly associated with signature 4.

Conclusions

The present study is the first to report a comparison in Chinese NSCLC patients with or without COSMIC mutational signature 4. These results will help find the Signature 4 related mutational process in NSCLC.

The Confounders of Cancer Immunotherapy: Roles of Lifestyle, Metabolic Disorders and Sociological Factors

Checkpoint blockade immunotherapy (CPI) is an effective treatment option for many types of cancers. Irrespective of its wide clinical implications, the overall efficacy remains unpredictable and even poor in certain pathologies such as breast cancer. Thus, it is imperative to understand the role of factors affecting its responsiveness. In this review, we provide an overview on the involvement of sociological factors, lifestyles and metabolic disorders in modulating the CPI response in patients from multiple malignancies. Lifestyle habits including exercise, and diet promoted therapeutic responsiveness while alcohol consumption mitigated the CPI effect by decreasing mutational burden and hampering antigen presentation by dendritic cells. Metabolic disorder such as obesity was recognized to enhance the PD-1 expression while diabetes and hypertension were consequences of CPI therapy rather than causes. Among the sociologic factors, sex and race positively influenced the CPI effectiveness on account of increased effector T cell activity and increased PD-1 expression while ageing impaired CPI responsiveness by decreasing functional T cell and increased toxicity. The combined effect of these factors was observed for obesity and gender, in which obese males had the most significant effect of CPI. Therefore these variables should be carefully considered before treating patients with CPI for optimal treatment outcome.

Efavirenz and Lopinavir/Ritonavir Alter Cell Cycle Regulation in Lung Cancer

Highly active anti-retroviral treatment (HAART) is currently the most effective treatment for HIV/AIDS. Additionally, HIV positive patients receiving HAART have a better health-related quality of life (HRQoL). Cancers previously associated with HIV/AIDS also known as the AIDS defining cancers (ADCs), such as Kaposi's sarcoma and non-Hodgkin's lymphoma have been on the decline since the introduction of HAART. However, non-AIDS defining cancers (NADCs), in particular, lung cancers have been documented to be on the rise. The association between the use of HAART components and lung carcinogenesis is poorly understood. This study aimed at elucidating the effects of two HAART components [efavirenz (EFV), and lopinavir/ritonavir (LPV/r)] on lung cancer. This was achieved through the use of in vitro cell biological approaches to assess cell health, including cell viability, Real Time Cell Analysis (RTCA) growth monitoring, evaluation of the cell cycle, and progression to apoptosis, following on drug treatments. At plasma level concentrations, both EFV and LPV/r induced S-phase arrest, while at lower concentrations both drugs promoted the progression of cells into G2/M phase following cell cycle FACS analysis. At higher concentrations although cell viability assays reflected anti-proliferative effects of the drugs, this was not statistically significant. RTCA showed a significant decline in cell viability in response to the highest dose of LPV/r. Dual staining by Annexin V-FITC and PI confirmed significant pro-apoptotic effects were promoted by LPV/r. Both EFV and LPV/r exert double-edged oncogenic effects on MRC-5 and A549 lung cells, acting to either promote cell proliferation or to enhance apoptosis. This is affected by EFV and LPV/r altering cell cycle progression, with a significant S-phase arrest, this being an indication of cellular stress, cytotoxicity, and DNA damage within the cell.

Integrative Analysis of the IQ Motif-Containing GTPase-Activating Protein Family Indicates That the IQGAP3-PIK3C2B Axis Promotes Invasion in Colon Cancer

Background

Colon cancer (CRC) is a common type of tumour, and IQGAP family proteins play an important role in many tumours. However, their roles in CRC remain unclear.

Methods

First, we searched many public databases to comprehensively analyze expression of IQGAPs in CRC. Next, real-time PCR, immunohistochemical (IHC), transwell, siRNA transfection and Western blot assays were used to evaluate relationships among IQGAP3 expression, clinical pathological parameters and CRC prognosis, and the underlying molecular mechanism was investigated.

Results

IQGAP3 was elevated in CRC tissues, whereas there was no significant change in expression of IQGAP1 or IQGAP2. Additionally, IQGAP3 expression in CRC tissues was associated with tumour progression, invasion and poor prognosis. In mechanistic studies, we found that IQGAP3 was positively coexpressed with PIK3C2B. In an in vitro assay, the PIK3C2B expression level was increased after exogenous overexpression of IQGAP3, resulting in the promotion of cell invasion, which was blocked by pretransfecting cells with PIK3C2B siRNA. Furthermore, we found that high expression of IQGAP3 and PIK3C2B correlated with tumour stage and vessel invasion in human CRC, whereby patients with high expression of both in tumours had a worse prognosis compared with patients with single-positive or double-negative tumours.

Conclusion

The results of our current study and corresponding previous studies provide evidence that IQGAP3 is elevated in CRC and promotes colon cancer growth and metastasis by regulating PIK3C2B activation.

Age-dependent expression of cancer-related genes in a long-lived seabird

Studies of model animals like mice and rats have led to great advances in our understanding of the process of tumorigenesis, but this line of study has less to offer for understanding the mechanisms of cancer resistance. Increasing the diversity of nonmodel species from the perspective of molecular mechanisms of natural cancer resistance can lead to new insights into the evolution of protective mechanisms against neoplastic processes and to a wider understanding of natural cancer defense mechanisms. Such knowledge could then eventually be harnessed for the development of human cancer therapies. We suggest here that seabirds are promising, albeit currently completely ignored candidates for studying cancer defense mechanisms, as they have a longer maximum life span than expected from their body size and rates of energy metabolism and may have thus evolved mechanisms to limit neoplasia progression, especially at older ages. We here apply a novel, intraspecific approach of comparing old and young seabirds for improving our understanding of aging and neoplastic processes in natural settings. We used the long-lived common gulls (Larus canus) for studying the age-related pattern of expression of cancer-related genes, based on transcriptome analysis and databases of orthologues of human cancer genes. The analysis of differently expressed cancer-related genes between young and old gulls indicated that similarly to humans, age is potentially affecting cancer risk in this species. Out of eleven differentially expressed cancer-related genes between the groups, three were likely artifactually linked to cancer. The remaining eight were downregulated in old gulls compared to young ones. The downregulation of five of them could be interpreted as a mechanism suppressing neoplasia risk and three as increasing the risk. Based on these results, we suggest that old gulls differ from young ones both from the aspect of cancer susceptibility and tumor suppression at the genetic level.

Novel Genetic Variations in Acute Myeloid Leukemia in Pakistani Population

Acute myeloid leukemia (AML) is a hematological malignancy characterized by clonal expansion of blast cells that exhibit great genetic heterogeneity. In this study, we describe the mutational landscape and its clinico-pathological significance in 26 myeloid neoplasm patients from a South Asian population (Pakistan) by using ultra-deep targeted next-generation DNA sequencing of 54 genes (∼5000×) and its subsequent bioinformatics analysis. The data analysis indicated novel non-silent somatic mutational events previously not reported in AML, including nine non-synonymous and one stop-gain mutations. Notably, two recurrent somatic non-synonymous mutations, i.e., STAG2 (causing p.L526F) and BCORL1 (p.A400V), were observed in three unrelated cases each. The BCOR was found to have three independent non-synonymous somatic mutations in three cases. Further, the SRSF2 with a protein truncating somatic mutation (p.Q88X) was observed for the first time in AML in this study. The prioritization of germline mutations with ClinVar, SIFT, Polyphen2, and Combined Annotation Dependent Depletion (CADD) highlighted 18 predicted deleterious/pathogenic mutations, including two recurrent deleterious mutations, i.e., a novel heterozygous non-synonymous SNV in GATA2 (p.T358P) and a frameshift insertion in NPM1 (p.L258fs), found in two unrelated cases each. The WT1 was observed with three independent potential detrimental germline mutations in three different cases. Collectively, non-silent somatic and/or germline mutations were observed in 23 (88.46%) of the cases (0.92 mutation per case). Furthermore, the pharmGKB database exploration showed a missense SNV rs1042522 in TP53, exhibiting decreased response to anti-cancer drugs, in 19 (73%) of the cases. This genomic profiling of AML provides deep insight into the disease pathophysiology. Identification of pharmacogenomics markers will help to adopt personalized approach for the management of AML patients in Pakistan.

Integrated analysis of optical mapping and whole-genome sequencing reveals intratumoral genetic heterogeneity in metastatic lung squamous cell carcinoma

Background

Intratumoral heterogeneity is a crucial factor to the outcome of patients and resistance to therapies, in which structural variants play an indispensable but undiscovered role.

Methods

We performed an integrated analysis of optical mapping and whole-genome sequencing on a primary tumor (PT) and matched metastases including lymph node metastasis (LNM) and tumor thrombus in the pulmonary vein (TPV). Single nucleotide variants, indels and structural variants were analyzed to reveal intratumoral genetic heterogeneity among tumor cells in different sites.

Results

Our results demonstrated there were less nonsynonymous somatic variants shared with PT in LNM than in TPV, while there were more structural variants shared with PT in LNM than in TPV. More private variants and its affected genes associated with tumorigenesis and progression were identified in TPV than in LNM. It should be noticed that optical mapping detected an average of 77.1% (74.5-78.5%) large structural variants (>5,000 bp) not detected by whole-genome sequencing and identified several structural variants private to metastases.

Conclusions

Our study does demonstrate structural variants, especially large structural variants play a crucial role in intratumoral genetic heterogeneity and optical mapping could make up for the deficiency of whole-genome sequencing to identify structural variants.