CNV Detection from Circulating Tumor DNA in Late Stage Non-Small Cell Lung Cancer Patients

Plasma circulating tumor DNA unveils the efficacy of PD-1 inhibitors and chemotherapy in advanced gastric cancer

Programmed Death Receptor 1 (PD-1) inhibitors, when combined with chemotherapy, have exhibited notable effectiveness in enhancing the survival outcomes of patients afflicted with advanced gastric cancer. However, it is important to acknowledge that not all patients derive substantial benefits from this therapeutic approach, highlighting the crucial necessity of identifying efficacious biomarkers to inform immunotherapy interventions. In this study, we sought to investigate the predictive utility of circulating tumor DNA (ctDNA) as a biomarker in a cohort of 30 patients diagnosed with advanced gastric cancer, all of whom underwent first-line treatment involving PD-1 inhibitor administration alongside chemotherapy. We procured peripheral blood samples both at baseline and following the completion of two treatment cycles. Additionally, baseline tissue specimens were collected for the purpose of genomic alteration assessment, employing both 47-gene and 737-gene next-generation sequencing panels for plasma and tumor tissue, respectively. We delineated a ctDNA response as the eradication of maximum variant allele frequencies relative to baseline levels. Notably, the objective response rate among individuals exhibiting a ctDNA response proved significantly superior in comparison to non-responders (P = 0.0073). Furthermore, patients who manifested a ctDNA response experienced markedly prolonged progression-free survival (PFS) and overall survival (OS) when juxtaposed with those devoid of a ctDNA response (median PFS: 15.6 vs. 6.0 months, P = 0.003; median OS: not reached [NR] vs. 9.0 months, P = 0.011). In summation, patients with advanced gastric cancer receiving first-line treatment with PD-1 inhibitors and chemotherapy, dynamic changes in ctDNA can serve as a potential biomarker for predicting treatment efficacy and long-term outcomes.

MicroRNA copy number alterations in the malignant transformation of pleomorphic adenoma to carcinoma ex pleomorphic adenoma

OBJECTIVE

This study used array comparative genomic hybridization to assess copy number alterations (CNAs) involving miRNA genes in pleomorphic adenoma (PA), recurrent pleomorphic adenoma (RPA), residual PA, and carcinoma ex pleomorphic adenoma (CXPA).

MATERIALS AND METHODS

We analyzed 13 PA, 4 RPA, 29 CXPA, and 14 residual PA using Nexus Copy Number Discovery software. The miRNAs genes affected by CNAs were evaluated based on their expression patterns and subjected to pathway enrichment analysis.

RESULTS

Across the groups, we found 216 CNAs affecting 2261 miRNA genes, with 117 in PA, 59 in RPA, 846 in residual PA, and 2555 in CXPA. The chromosome 8 showed higher involvement in altered miRNAs in PAs and CXPA patients. Six miRNA genes were shared among all groups. Additionally, miR-21, miR-455-3p, miR-140, miR-320a, miR-383, miR-598, and miR-486 were prominent CNAs found and is implicated in carcinogenesis of several malignant tumors. These miRNAs regulate critical signaling pathways such as aerobic glycolysis, fatty acid biosynthesis, and cancer-related pathways.

CONCLUSION

This study was the first to explore CNAs in miRNA-encoding genes in the PA-CXPA sequence. The findings suggest the involvement of numerous miRNA genes in CXPA development and progression by regulating oncogenic signaling pathways.

Analytical evaluation of circulating tumor DNA sequencing assays

In China, circulating tumor DNA analysis is widely used and numerous assays are available. Systematic evaluation to help users make informed selections is needed. Nine circulating tumor DNA assays, including one benchmark assay, were evaluated using 23 contrived reference samples. There were two sample types (cell-free DNA and plasma samples), three circulating tumor DNA inputs (low, < 20 ng; medium, 20-50 ng; high, > 50 ng), two variant allele frequency ranges (low, 0.1-0.5%; intermediate, 0.5-2.5%), and four variant types (single nucleotide, insertion/deletion, structural, and copy number). Sensitivity, specificity, reproducibility, and all processes from cell-free DNA extraction to bioinformatics analysis were assessed. The test assays were generally comparable or superior to the benchmark assay, demonstrating high analytical sensitivity. Variations in circulating tumor DNA extraction and quantification efficiency, sensitivity, and reproducibility were observed, particularly at lower inputs. These findings will guide circulating tumor DNA assay choice for research and clinical studies, allowing consideration of multiple technical parameters.

NGS-based Tissue-Blood TMB Comparison and Blood-TMB Monitoring in Stage-III Non-Small Cell Lung Cancer Treated with Concurrent Chemoradiotherapy

In this study, we analyzed the blood-based TMB (b-TMB) and its dynamic changes in patients with locally advanced non-small cell lung cancer (LA-NSCLC) who received concurrent chemoradiotherapy. Baseline tissue and blood TMB from 15 patients showed a strong positive correlation (Pearson correlation = 0.937), and nearly all mutations were markedly reduced in the later course of treatment, indicating a treatment-related response. This study suggests that in patients with LA-NSCLC, b-TMB is a reliable biomarker, and its dynamic monitoring can help distinguish patients who might benefit most from the consolidated immunotherapy.

Copy Number Variations in Pancreatic Cancer: From Biological Significance to Clinical Utility

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer, characterized by high tumor heterogeneity and a poor prognosis. Inter- and intra-tumoral heterogeneity in PDAC is a major obstacle to effective PDAC treatment; therefore, it is highly desirable to explore the tumor heterogeneity and underlying mechanisms for the improvement of PDAC prognosis. Gene copy number variations (CNVs) are increasingly recognized as a common and heritable source of inter-individual variation in genomic sequence. In this review, we outline the origin, main characteristics, and pathological aspects of CNVs. We then describe the occurrence of CNVs in PDAC, including those that have been clearly shown to have a pathogenic role, and further highlight some key examples of their involvement in tumor development and progression. The ability to efficiently identify and analyze CNVs in tumor samples is important to support translational research and foster precision oncology, as copy number variants can be utilized to guide clinical decisions. We provide insights into understanding the CNV landscapes and the role of both somatic and germline CNVs in PDAC, which could lead to significant advances in diagnosis, prognosis, and treatment. Although there has been significant progress in this field, understanding the full contribution of CNVs to the genetic basis of PDAC will require further research, with more accurate CNV assays such as single-cell techniques and larger cohorts than have been performed to date.

DNA Copy Number Alterations and Copy Neutral Loss of Heterozygosity in Adult Ph-Negative Acute B-Lymphoblastic Leukemia: Focus on the Genes Involved

The landscape of chromosomal aberrations in the tumor cells of the patients with B-ALL is diverse and can influence the outcome of the disease. Molecular karyotyping at the onset of the disease using chromosomal microarray (CMA) is advisable to identify additional molecular factors associated with the prognosis of the disease. Molecular karyotyping data for 36 patients with Ph-negative B-ALL who received therapy according to the ALL-2016 protocol are presented. We analyzed copy number alterations and their prognostic significance for CDKN2A/B, DMRTA, DOCK8, TP53, SMARCA2, PAX5, XPA, FOXE1, HEMGN, USP45, RUNX1, NF1, IGF2BP1, ERG, TMPRSS2, CRLF2, FGFR3, FLNB, IKZF1, RUNX2, ARID1B, CIP2A, PIK3CA, ATM, RB1, BIRC3, MYC, IKZF3, ETV6, ZNF384, PTPRJ, CCL20, PAX3, MTCH2, TCF3, IKZF2, BTG1, BTG2, RAG1, RAG2, ELK3, SH2B3, EP300, MAP2K2, EBI3, MEF2D, MEF2C, CEBPA, and TBLXR1 genes, choosing t(4;11) and t(7;14) as reference events. Of the 36 patients, only 5 (13.8%) had a normal molecular karyotype, and 31 (86.2%) were found to have various molecular karyotype abnormalities-104 deletions, 90 duplications or amplifications, 29 cases of cnLOH and 7 biallelic/homozygous deletions. We found that 11q22-23 duplication involving the BIRC3, ATM and MLL genes was the most adverse prognostic event in the study cohort.

Association between the copy number variation of CCSER1 gene and growth traits in Chinese Capra hircus (goat) populations

Recently, Coiled-coil serine-rich protein 1 (CCSER1) gene is reported to be related to economic traits in livestock, and become a hotspot. In our study, we detected CCSER1 gene CNV in 693 goats from six breeds (GZB, GZW, AN, BH, HG, TH) by quantitative real-time PCR (qPCR) and the association analysis between the types of CNV and growth traits. Then, CCSER1 gene expression pattern was discovered in seven tissues from NB goats. Our results showed that the CCSER1 gene copy numbers were distributed differently in the aforementioned six breeds. The type of CCSER1 gene CNV was significantly associated with body weight and heart girth traits in GZW goat, in which individuals with deletion type were dominant in body weight trait (P < 0.05), while the normal type individuals were more advantageous in heart girth trait (P < 0.01); and there was a significant association with heart girth in TH goat (P < 0.05), which normal type was the dominant one. The expression profile revealed that CCSER1 gene has the highest level in the lung, followed by the small intestine and heart. In conclusion, our result is dedicated to an in-depth study of the novel CCSER1 gene CNV site and to provide essential information for Chinese goats molecular selective breeding in the future.

Enhancing Lung Cancer Classification through Integration of Liquid Biopsy Multi-Omics Data with Machine Learning Techniques

Early detection of lung cancer is crucial for patient survival and treatment. Recent advancements in next-generation sequencing (NGS) analysis enable cell-free DNA (cfDNA) liquid biopsy to detect changes, like chromosomal rearrangements, somatic mutations, and copy number variations (CNVs), in cancer. Machine learning (ML) analysis using cancer markers is a highly promising tool for identifying patterns and anomalies in cancers, making the development of ML-based analysis methods essential. We collected blood samples from 92 lung cancer patients and 80 healthy individuals to analyze the distinction between them. The detection of lung cancer markers Cyfra21 and carcinoembryonic antigen (CEA) in blood revealed significant differences between patients and controls. We performed machine learning analysis to obtain AUC values via Adaptive Boosting (AdaBoost), Multi-Layer Perceptron (MLP), and Logistic Regression (LR) using cancer markers, cfDNA concentrations, and CNV screening. Furthermore, combining the analysis of all multi-omics data for ML showed higher AUC values compared with analyzing each element separately, suggesting the potential for a highly accurate diagnosis of cancer. Overall, our results from ML analysis using multi-omics data obtained from blood demonstrate a remarkable ability of the model to distinguish between lung cancer and healthy individuals, highlighting the potential for a diagnostic model against lung cancer.

The Development and Role of Capmatinib in the Treatment of MET-Dysregulated Non-Small Cell Lung Cancer-A Narrative Review

Non-small cell lung cancer (NSCLC) is a leading cause of death, but over the past decade, there has been tremendous progress in the field with new targeted therapies. The mesenchymal-epithelial transition factor (MET) proto-oncogene has been implicated in multiple solid tumors, including NSCLC, and dysregulation in NSCLC from MET can present most notably as MET exon 14 skipping mutation and amplification. From this, MET tyrosine kinase inhibitors (TKIs) have been developed to treat this dysregulation despite challenges with efficacy and reliable biomarkers. Capmatinib is a Type Ib MET TKI first discovered in 2011 and was FDA approved in August 2022 for advanced NSCLC with MET exon 14 skipping mutation. In this narrative review, we discuss preclinical and early-phase studies that led to the GEOMETRY mono-1 study, which showed beneficial efficacy in MET exon 14 skipping mutations, leading to FDA approval of capmatinib along with Foundation One CDx assay as its companion diagnostic assay. Current and future directions of capmatinib are focused on improving the efficacy, overcoming the resistance of capmatinib, and finding approaches for new indications of capmatinib such as acquired MET amplification from epidermal growth factor receptor (EGFR) TKI resistance. Clinical trials now involve combination therapy with capmatinib, including amivantamab, trametinib, and immunotherapy. Furthermore, new drug agents, particularly antibody-drug conjugates, are being developed to help treat patients with acquired resistance from capmatinib and other TKIs.

Development and validation of postoperative circulating tumor DNA combined with clinicopathological risk factors for recurrence prediction in patients with stage I-III colorectal cancer

BACKGROUND

Circulating tumor DNA (ctDNA) detection following curative-intent surgery could directly reflect the presence of minimal residual disease, the ultimate cause of clinical recurrence. However, ctDNA is not postoperatively detected in ≥ 50% of patients with stage I-III colorectal cancer (CRC) who ultimately recur. Herein we sought to improve recurrence risk prediction by combining ctDNA with clinicopathological risk factors in stage I-III CRC.

METHODS

Two independent cohorts, both consisting of early-stage CRC patients who underwent curative surgery, were included: (i) the discovery cohort (N = 124) with tumor tissues and postoperative plasmas for ctDNA determination; and (ii) the external validation cohort (N = 125) with available ctDNA results. In the discovery cohort, somatic variations in tumor tissues and plasmas were determined via a 733-gene and 127-gene next-generation sequencing panel, respectively.

RESULTS

In the discovery cohort, 17 of 108 (15.7%) patients had detectable ctDNA. ctDNA-positive patients had a significantly high recurrence rate (76.5% vs. 16.5%, P < 0.001) and short recurrence-free survival (RFS; P < 0.001) versus ctDNA-negative patients. In addition to ctDNA status, the univariate Cox model identified pathologic stage, lymphovascular invasion, nerve invasion, and preoperative carcinoembryonic antigen level associated with RFS. We combined the ctDNA and clinicopathological risk factors (CTCP) to construct a model for recurrence prediction. A significantly higher recurrence rate (64.7% vs. 8.1%, P < 0.001) and worse RFS (P < 0.001) were seen in the high-risk patients classified by the CTCP model versus those in the low-risk patients. Receiver operating characteristic analysis demonstrated that the CTCP model outperformed ctDNA alone at recurrence prediction, which increased the sensitivity of 2 year RFS from 49.6% by ctDNA alone to 87.5%. Harrell's concordance index, calibration curve, and decision curve analysis also suggested that the CTCP model had good discrimination, consistency, and clinical utility. These results were reproduced in the validation cohort.

CONCLUSION

Combining postoperative ctDNA and clinical risk may better predict recurrence than ctDNA alone for developing a personalized postoperative management strategy for CRC.

MET gene amplification is a mechanism of resistance to entrectinib in ROS1+ NSCLC

BACKGROUND

ROS1 tyrosine kinase inhibitors (TKIs) have demonstrated significant clinical benefit for ROS1+ NSCLC patients. However, TKI resistance inevitably develops through ROS1 kinase domain (KD) modification or another kinase driving bypass signaling. While multiple TKIs have been designed to target ROS1 KD mutations, less is known about bypass signaling in TKI-resistant ROS1+ lung cancers.

METHODS

Utilizing a primary, patient-derived TPM3-ROS1 cell line (CUTO28), we derived an entrectinib-resistant line (CUTO28-ER). We evaluated proliferation and signaling responses to TKIs, and utilized RNA sequencing, whole exome sequencing, and fluorescence in situ hybridization to detect transcriptional, mutational, and copy number alterations, respectively. We substantiated in vitro findings using a CD74-ROS1 NSCLC patient's tumor samples. Last, we analyzed circulating tumor DNA (ctDNA) from ROS1+ NSCLC patients in the STARTRK-2 entrectinib trial to determine the prevalence of MET amplification.

RESULTS

CUTO28-ER cells did not exhibit ROS1 KD mutations. MET TKIs inhibited proliferation and downstream signaling and MET transcription was elevated in CUTO28-ER cells. CUTO28-ER cells displayed extrachromosomal (ecDNA) MET amplification without MET activating mutations, exon 14 skipping, or fusions. The CD74-ROS1 patient samples illustrated MET amplification while receiving ROS1 TKI. Finally, two of 105 (1.9%) entrectinib-resistant ROS1+ NSCLC STARTRK-2 patients with ctDNA analysis at enrollment and disease progression displayed MET amplification.

CONCLUSIONS

Treatment with ROS1-selective inhibitors may lead to MET-mediated resistance. The discovery of ecDNA MET amplification is noteworthy, as ecDNA is associated with more aggressive cancers. Following progression on ROS1-selective inhibitors, MET gene testing and treatments targeting MET should be explored to overcome MET-driven resistance.

Diagnostic and Therapeutic Potential of Circulating-Free DNA and Cell-Free RNA in Cancer Management

Over time, molecular biology and genomics techniques have been developed to speed up the early diagnosis and clinical management of cancer. These therapies are often most effective when administered to the subset of malignancies harboring the target identified by molecular testing. Important advances in applying molecular testing involve circulating-free DNA (cfDNA)- and cell-free RNA (cfRNA)-based liquid biopsies for the diagnosis, prognosis, prediction, and treatment of cancer. Both cfDNA and cfRNA are sensitive and specific biomarkers for cancer detection, which have been clinically proven through multiple randomized and prospective trials. These help in cancer management based on the noninvasive evaluation of size, quantity, and point mutations, as well as copy number alterations at the tumor site. Moreover, personalized detection of ctDNA helps in adjuvant therapeutics and predicts the chances of recurrence of cancer and resistance to cancer therapy. Despite the controversial diagnostic values of cfDNA and cfRNA, many clinical trials have been completed, and the Food and Drug Administration has approved many multigene assays to detect genetic alterations in the cfDNA of cancer patients. In this review, we underpin the recent advances in the physiological roles of cfDNA and cfRNA, as well as their roles in cancer detection by highlighting recent clinical trials and their roles as prognostic and predictive markers in cancer management.

Identification of a dysregulated ceRNA network modulated by copy number variation-driven lncRNAs in lung squamous cell carcinoma

Lung cancer is primarily responsive for cancer death, and its progression is aggressively affected by copy number variation (CNV). Through bioinformatics approach, a ceRNA network of CNV-driven lncRNAs in lung squamous cell carcinoma (LUSC) patients was constructed. Data on normal and LUSC tumor tissue from The Cancer Genome Atlas (TCGA)-LUSC dataset were subjected to differential analysis, and differentially expressed lncRNAs (DElncRNAs), DEmiRNAs, and DEmRNAs were obtained. Based on TCGA-LUSC, CNVs of normal and tumor tissue samples were then compared using a Chi-square test, and lncRNAs were intersected based on their CNVs and expression alternation. In combination with the Kruskal-Wallis test, CNV-driven lncRNAs were acquired. Afterwards, miRNAs and mRNAs that interacted with CNV-driven lncRNAs were obtained based on databases (LncBase, starBase, miRDB, mirDIP and TargetScan), DElncRNAs, DEmiRNAs and DEmRNAs, and correlation analysis. The acquired lncRNAs, miRNAs and mRNAs were subjected to Cytoscape software to construct a CNV-driven ceRNA network, which involved 5 lncRNAs (MIR143HG, LINC00702, MIR22HG, RP11-180 N14.1, RP11-473 M20.9), 6 miRNAs (miR-3200-3p, miR-1301-3p, miR-93-3p, miR-96-5p, miR-96-5p, miR-130b-5p, miR-205-5p) and 80 mRNAs. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analyses indicated that downstream mRNAs were mainly correlated with blood vessel development and T cell-mediated immunity. In summary, we devoted to analyzing CNV-related lncRNAs, mRNAs, and miRNAs in LUSC, thus clarifying 5 lncRNAs that may influence the malignant progression of LUSC. The ceRNA network regulated by these lncRNAs may be the novel pathogenesis of LUSC.

Mutations of PI3K-AKT-mTOR pathway as predictors for immune cell infiltration and immunotherapy efficacy in dMMR/MSI-H gastric adenocarcinoma

BACKGROUND

A significant subset of mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) gastric adenocarcinomas (GAC) are resistant to immune checkpoint inhibitors (ICIs), yet the underlying mechanism remains largely unknown. We sought to investigate the genomic correlates of the density of tumor-infiltrating immune cells (DTICs) and primary resistance to ICI treatment.

METHODS

Four independent cohorts of MSI-H GAC were included: (i) the surgery cohort (n = 175) with genomic and DTIC data, (ii) the 3DMed cohort (n = 32) with genomic and PD-L1 data, (iii) the Cancer Genome Atlas (TCGA) cohort (n = 73) with genomic, transcriptomic, and survival data, and (iv) the ICI treatment cohort (n = 36) with pre-treatment genomic profile and ICI efficacy data.

RESULTS

In the dMMR/MSI-H GAC, the number of mutated genes in the PI3K-AKT-mTOR pathway (NMP) was positively correlated with tumor mutational burden (P < 0.001) and sensitivity to PI3K-AKT-mTOR inhibitors and negatively correlated with CD3⁺ (P < 0.001), CD4⁺ (P = 0.065), CD8⁺ (P = 0.004), and FOXP3⁺ cells (P = 0.033) in the central-tumor rather than invasive-margin area, and the transcription of immune-related genes. Compared to the NMP-low (NMP = 0/1) patients, the NMP-high (NMP ≥ 2) patients exhibited a poorer objective response rate (29.4% vs. 85.7%, P < 0.001), progression-free survival (HR = 3.40, P = 0.019), and overall survival (HR = 3.59, P = 0.048) upon ICI treatment.

CONCLUSIONS

Higher NMP was identified as a potential predictor of lower DTICs and primary resistance to ICIs in the dMMR/MSI-H GAC. Our results highlight the possibility of using mutational data to estimate DTICs and administering the PI3K-AKT-mTOR inhibitor as an immunotherapeutic adjuvant in NMP-high subpopulation to overcome the resistance to ICIs.

Genetic Characteristics Associated With Drug Resistance in Lung Cancer and Colorectal Cancer Using Whole Exome Sequencing of Cell-Free DNA

Circulating cell-free DNA (cfDNA) can be used to characterize tumor genomes through next-generation sequencing (NGS)-based approaches. We aim to identify novel genetic alterations associated with drug resistance in lung cancer and colorectal cancer patients who were treated with EGFR-targeted therapy and cytotoxic chemotherapy through whole exome sequencing (WES) of cfDNA. A cohort of 18 lung cancer patients was treated with EGFR TKI or cytotoxic chemotherapy, and a cohort of 37 colorectal cancer patients was treated with EGFR monoclonal antibody or cytotoxic chemotherapy alone. Serum samples were drawn before and after development of drug resistance, and the genetic mutational profile was analyzed with WES data. For 110 paired cfDNA and matched germline DNA WES samples, mean coverage of 138x (range, 52–208.4x) and 47x (range, 30.5–125.1x) was achieved, respectively. After excluding synonymous variants, mutants identified in more than two patients at the time of acquired resistance were selected. Seven genes in lung cancer and 16 genes in colorectal cancer were found, namely, APC, TP53, KRAS, SMAD4, and EGFR. In addition, the GPR155 I357S mutation in lung cancer and ADAMTS20 S1597P and TTN R7415H mutations in colorectal cancer were frequently detected at the time of acquired resistance, indicating that these mutations have an important function in acquired resistance to chemotherapy. Our data suggest that novel genetic variants associated with drug resistance can be identified using cfDNA WES. Further validation is necessary, but these candidate genes are promising therapeutic targets for overcoming drug resistance in lung cancer and colorectal cancer.

Next-Generation Sequencing of Patients With Breast Cancer in Community Oncology Clinics

PURPOSE

Molecular biomarkers informing disease diagnosis, prognosis, and treatment decisions in patients with breast cancer are being uncovered by next-generation sequencing (NGS) technologies. In this study, we survey how NGS is used for patients with breast cancer in real-world settings with a focus on physician behaviors and sequencing results.

METHODS

We conducted a retrospective analysis of patients with breast cancer who received NGS testing from commercial vendors as part of standard of care from 2014 to 2019. A total of 2,635 NGS reports from 2,316 unique breast cancer patients were assessed. Hormone receptor and human epidermal growth factor receptor 2 statuses were abstracted from patient medical records. Comparative gene amplification and mutation frequencies were analyzed using Pearson's correlation and Lin's concordance statistics.

RESULTS

The number of physicians ordering NGS tests for patients with breast cancer increased more than six-fold from 2014 to 2019. Tissue- and plasma-based tests were ordered roughly equally by 2019, with plasma-based testing ordered most frequently in hormone receptor-positive subtypes. Patients with triple-negative breast cancer were most likely to receive NGS testing. Gene amplifications including ERBB2 were detected less frequently in our real-world data set as compared to previous genomic landscape studies, whereas the opposite was true for gene mutations including ESR1. Pathogenic mutations in the PI3K pathway (38.6%) and DNA damage repair pathway (11.0%) were frequently reported. Alterations were also reported across other cellular pathways.

CONCLUSION

Overall, we found that an increasing number of physicians in community settings are adopting NGS in the care of patients with breast cancer. Discrepancies between our real-world NGS data and previous genomic landscape studies are likely owed to the prevalence of plasma-based testing in community oncology clinics, as the reference data were from tissue-based NGS alone.

Evaluation of a Targeted Next-Generation Sequencing Panel for the Non-Invasive Detection of Variants in Circulating DNA of Colorectal Cancer

Molecular profiling of circulating cell-free DNA (cfDNA) has shown utility for the management of colorectal cancer (CRC). TruSight Tumor 170 (TST170) is a next-generation sequencing (NGS) panel that covers 170 cancer-related genes, including KRAS, which is a key driver gene in CRC. We evaluated the capacity of TST170 to detect gene variants in cfDNA from a retrospective cohort of 20 metastatic CRC patients with known KRAS variants in tumor tissue and in cfDNA previously analyzed by pyrosequencing and BEAMing, respectively. The cfDNA of most of the patients (95%) was successfully sequenced. We frequently detected variants with clinical significance in KRAS (79%, 15/19) and PIK3CA (26%, 5/19) genes. Variants with potential clinical significance were also identified in another 27 cancer genes, such as APC. The type of KRAS variant detected in cfDNA by TST170 showed high concordance with those detected in tumor tissue (77%), and very high concordance with cfDNA analyzed by BEAMing (94%). The variant allele fractions for KRAS obtained in cfDNA by TST170 and BEAMing correlated strongly. This proof-of-principle study indicates that targeted NGS analysis of cfDNA with TST170 could be useful for non-invasive detection of gene variants in metastatic CRC patients, providing an assay that could be easily implemented for detecting somatic alterations in the clinic.

Liquid Biopsy Biomarkers for Immunotherapy in Non-Small Cell Lung Carcinoma: Lessons Learned and the Road Ahead

Over the recent years, advances in the development of anti-cancer treatments, particularly the implementation of ICIs (immune checkpoint inhibitors), have resulted in increased survival rates in NSCLC (non-small cell lung cancer) patients. However, a significant proportion of patients does not seem respond to immunotherapy, and some individuals even develop secondary resistance to treatment. Therefore, it is imperative to correctly identify the patients that will benefit from ICI therapy in order to tailor therapeutic options in an individualised setting, ultimately benefitting both the patient and the health system. Many different biomarkers have been explored to correctly stratify patients and predict response to immunotherapy, but liquid biopsy approaches have recently arisen as an interesting opportunity to predict and monitor treatment response due to their logistic accessibility. This review summarises the current data and efforts in the field of ICI response biomarkers in NSCLC patients and highlights advantages and limitations as we discuss the road to clinical implementation.

Evaluating the analytical validity of circulating tumor DNA sequencing assays for precision oncology

Circulating tumor DNA (ctDNA) sequencing is being rapidly adopted in precision oncology, but the accuracy, sensitivity and reproducibility of ctDNA assays is poorly understood. Here we report the findings of a multi-site, cross-platform evaluation of the analytical performance of five industry-leading ctDNA assays. We evaluated each stage of the ctDNA sequencing workflow with simulations, synthetic DNA spike-in experiments and proficiency testing on standardized, cell-line-derived reference samples. Above 0.5% variant allele frequency, ctDNA mutations were detected with high sensitivity, precision and reproducibility by all five assays, whereas, below this limit, detection became unreliable and varied widely between assays, especially when input material was limited. Missed mutations (false negatives) were more common than erroneous candidates (false positives), indicating that the reliable sampling of rare ctDNA fragments is the key challenge for ctDNA assays. This comprehensive evaluation of the analytical performance of ctDNA assays serves to inform best practice guidelines and provides a resource for precision oncology.

Circulating tumour DNA reveals genetic traits of patients with intraductal carcinoma of the prostate

OBJECTIVES

To investigate the genetic alterations of patients with prostate cancer (PCa) with and without intraductal carcinoma of the prostate (IDC-P).

PATIENTS AND METHODS

We performed targeted sequencing of plasma cell-free DNA on 161 patients with prostate adenocarcinoma (PAC) with IDC-P and 84 without IDC-P. Genomic alterations were compared between these two groups. The association between genetic alterations and patients' survival outcomes was also explored.

RESULTS

We identified that 29.8% (48/161) and 21.4% (18/84) of patients with and without IDC-P harboured genomic alterations in DNA repair pathways, respectively (P = 0.210). Pathogenic germline DNA repair alterations were frequently detected in IDC-P carriers compared to IDC-P non-carriers (11.8% [19/161] vs 2.4% [two of 84], P = 0.024). Germline BReast CAncer type 2 susceptibility protein (BRCA2) and somatic cyclin-dependent kinase 12 (CDK12) defects were specifically identified in IDC-P carriers relative to PAC (BRCA2: 8.7% [14/161] vs 0% and CDK12: 6.8% [11/161] vs 1.2% [one of 84]). Patients with IDC-P had a distinct androgen receptor (AR) pathway alteration, characterised by an enrichment of nuclear receptor corepressor 2 (NCOR2) mutations compared with patients with pure PAC (21.1% [34/161] vs 6.0% [five of 84], P = 0.004). Increased AR alterations were detected in patients harbouring tumours with an IDC-P proportion of ≥10% vs those with an IDC-P proportion of <10% (6.4% [five of 78] vs 18.1% [15/83], P = 0.045). For IDC-P carriers, tumour protein p53 (TP53) mutation was associated with shorter castration-resistant-free survival (median 10.9 vs 28.9 months, P = 0.026), and BRCA2 alteration was related to rapid prostate-specific antigen progression for those receiving abiraterone treatment (median 9.1 vs 11.9 months, P = 0.036).

CONCLUSION

Our findings provide genomic evidence explaining the aggressive phenotype of tumours with IDC-P, highlighting the potential therapeutic strategies for this patient population.

Circulating tumor DNA in lung cancer: real-time monitoring of disease evolution and treatment response

Lung cancer is one of the leading causes of all cancer-related deaths. Circulating tumor DNA (ctDNA) is released from apoptotic and necrotic tumor cells. Several sensitive techniques have been invented and adapted to quantify ctDNA genomic alterations. Applications of ctDNA in lung cancer include early diagnosis and detection, prognosis prediction, detecting mutations and structural alterations, minimal residual disease, tumor mutational burden, and tumor evolution tracking. Compared to surgical biopsy and radiographic imaging, the advantages of ctDNA are that it is a non-invasive procedure, allows real-time monitoring, and has relatively high sensitivity and specificity. Given the massive research on non-small cell lung cancer, attention should be paid to small cell lung cancer.

Novel variants of the PCCB gene in Chinese patients with propionic acidemia

BACKGROUND AND AIMS

Propionic acidemia (PA) is an autosomal recessive metabolic disorder caused by a deficiency of propionyl-CoA carboxylase and mutations in the PCCA and PCCB genes. In this study, we investigated the clinical characteristics of individuals with PA and conducted genetic analyses to provide new genetic evidence for the diagnosis of PA.

MATERIALS AND METHODS

We conducted whole-exome sequencing and Sanger sequencing in four individuals with PA from three unrelated Chinese families. We also performed a structural analysis of the PCCB protein variants. Couples from the three families included in our study underwent in vitro fertilization with preimplantation genetic testing.

RESULTS

We found five variants of PCCB. These biallelic variants were inherited from heterozygous parental carriers and were located in the functional domain, absent in human population genome datasets, and predicted to be deleterious. These findings indicate that the variants might be responsible for the clinical features observed in these particular patients with PA. Through successful embryo transfer and implantation, one of the couples fortunately gave birth to a healthy child.

CONCLUSION

Overall, our study can expand the mutation spectrum of PCCB and provide useful information for the prenatal diagnosis of PA and genetic counseling for affected individuals.

Multi-omics analysis of genomics, epigenomics and transcriptomics for molecular subtypes and core genes for lung adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is the most frequently diagnosed histological subtype of lung cancer. Our purpose was to explore molecular subtypes and core genes for LUAD using multi-omics analysis.

Methods

Methylation, transcriptome, copy number variation (CNV), mutations and clinical feature information concerning LUAD were retrieved from The Cancer Genome Atlas Database (TCGA). Molecular subtypes were conducted via the “iClusterPlus” package in R, followed by Kaplan-Meier survival analysis. Correlation between iCluster subtypes and immune cells was analyzed. Core genes were screened out by integration of methylation, CNV and gene expression, which were externally validated by independent datasets.

Results

Two iCluster subtypes were conducted for LUAD. Patients in imprinting centre 1 (iC1) subtype had a poorer prognosis than those in iC2 subtype. Furthermore, iC2 subtype had a higher level of B cell infiltration than iC1 subtype. Two core genes including CNTN4 and RFTN1 were screened out, both of which had higher expression levels in iC2 subtype than iC1 subtype. There were distinct differences in CNV and methylation of them between two subtypes. After validation, low expression of CNTN4 and RFTN1 predicted poorer clinical outcomes for LUAD patients.

Conclusion

Our findings comprehensively analyzed genomics, epigenomics, and transcriptomics of LUAD, offering novel underlying molecular mechanisms for LUAD. Two multi-omics-based core genes (CNTN4 and RFTN1) could become potential therapeutic targets for LUAD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07888-4.

Profiling of circulating tumor DNA and tumor tissue for treatment selection in patients with advanced and refractory carcinoma: a prospective, two-stage phase II Individualized Cancer Treatment trial

BACKGROUND

Molecular profiling (MP) represents an opportunity to match patients to a targeted therapy and when tumor tissue is unavailable, circulating tumor deoxyribonucleic acid (ctDNA) can be harnessed as a non-invasive analyte for this purpose. We evaluated the success of a targeted therapy selected by profiling of ctDNA and tissue in patients with advanced and refractory carcinoma.

PATIENTS AND METHODS

A blood draw as well as an optional tissue biopsy were obtained for MP. Whole-genome sequencing and a cancer hotspot panel were performed, and publicly available databases were used to match the molecular profile to targeted treatments. The primary endpoint was the progression-free survival (PFS) ratio (PFS on MP-guided therapy/PFS on the last evidence-based therapy), whereas the success of the targeted therapy was defined as a PFS ratio ⩾1.2. To test the impact of molecular profile-treatment matching strategies, we retrospectively analyzed selected cases via the CureMatch PreciGENE™ decision support algorithm.

RESULTS

Interim analysis of 24 patients yielded informative results from 20 patients (83%). A potential tumor-specific drug could be matched in 11 patients (46%) and eight (33%) received a matched treatment. Median PFS in the matched treatment group was 61.5 days [interquartile range (IQR) 49.8-71.0] compared with 81.5 days (IQR 68.5-117.8) for the last evidence-based treatment, resulting in a median PFS ratio of 0.7 (IQR 0.6-0.9). Hence, as no patient experienced a PFS ratio ⩾1.2, the study was terminated. Except for one case, the CureMatch analysis identified either a two-drug or three-drug combination option.

CONCLUSIONS

Our study employed a histotype-agnostic approach to harness molecular profiling data from both ctDNA and metastatic tumor tissue. The outcome results indicate that more innovative approaches to study design and matching algorithms are necessary to achieve improved patient outcomes.EU Clinical Trials Registry (https://www.clinicaltrialsregister.eu): EudraCT: 2014-005341-44.

Copy number variation: Characteristics, evolutionary and pathological aspects

Copy number variants (CNVs) were the subject of extensive research in the past years. They are common features of the human genome that play an important role in evolution, contribute to population diversity, development of certain diseases, and influence host–microbiome interactions. CNVs have found application in the molecular diagnosis of many diseases and in non-invasive prenatal care, but their full potential is only emerging. CNVs are expected to have a tremendous impact on screening, diagnosis, prognosis, and monitoring of several disorders, including cancer and cardiovascular disease. Here, we comprehensively review basic definitions of the term CNV, outline mechanisms and factors involved in CNV formation, and discuss their evolutionary and pathological aspects. We suggest a need for better defined distinguishing criteria and boundaries between known types of CNVs.

Exploring the Effect of Differentially Expressed Long Non-coding RNAs Driven by Copy Number Variation on Competing Endogenous RNA Network by Mining Lung Adenocarcinoma Data

Lung cancer is the first cause of cancer death, and gene copy number variation (CNV) is a vital cause of lung cancer progression. Prognosis prediction of patients followed by medication guidance by detecting CNV of lung cancer is emerging as a promising precise treatment in the future. In this paper, the differences in CNV and gene expression between cancer tissue and normal tissue of lung adenocarcinoma (LUAD) from The Cancer Genome Atlas Lung Adenocarcinoma data set were firstly analyzed, and greater differences were observed. Furthermore, CNV-driven differentially expressed long non-coding RNAs (lncRNAs) were screened out, and then, a competing endogenous RNA (ceRNA) regulatory network related to the gene CNV was established, which involved 9 lncRNAs, seven microRNAs, and 178 downstream messenger RNAs (mRNAs). Pathway enrichment analyses sequentially performed revealed that the downstream mRNAs were mainly enriched in biological pathways related to cell division, DNA repair, and so on, indicating that these mRNAs mainly affected the replication and growth of tumor cells. Besides, the relationship between lncRNAs and drug effects was explored based on previous studies, and it was found that LINC00511 and LINC00942 in the CNV-associated ceRNA network could be used to determine tumor response to drug treatment. As examined, the drugs affected by these two lncRNAs mainly targeted metabolism, target of rapamycin signaling pathway, phosphatidylinositol-3-kinase signaling pathway, epidermal growth factor receptor signaling pathway, and cell cycle. In summary, the present research was devoted to analyzing CNV, lncRNA, mRNA, and microRNA of lung cancer, and nine lncRNAs that could affect the CNV-associated ceRNA network we constructed were identified, two of which are promising in determining tumor response to drug treatment.

Copy Number Variation: Methods and Clinical Applications

Gains and losses of large segments of genomic DNA, known as copy number variants (CNVs) gained considerable interest in clinical diagnostics lately, as particular forms may lead to inherited genetic diseases. In recent decades, researchers developed a wide variety of cytogenetic and molecular methods with different detection capabilities to detect clinically relevant CNVs. In this review, we summarize methodological progress from conventional approaches to current state of the art techniques capable of detecting CNVs from a few bases up to several megabases. Although the recent rapid progress of sequencing methods has enabled precise detection of CNVs, determining their functional effect on cellular and whole-body physiology remains a challenge. Here, we provide a comprehensive list of databases and bioinformatics tools that may serve as useful assets for researchers, laboratory diagnosticians, and clinical geneticists facing the challenge of CNV detection and interpretation.

Detecting Resistance to Therapeutic ALK Inhibitors in Tumor Tissue and Liquid Biopsy Markers: An Update to a Clinical Routine Practice

The survival of most patients with advanced stage non-small cell lung cancer is prolonged by several months when they are treated with first- and next-generation inhibitors targeting ALK rearrangements, but resistance inevitably emerges. Some of the mechanisms of resistance are sensitive to novel ALK inhibitors but after an initial tumor response, more or less long-term resistance sets in. Therefore, to adapt treatment it is necessary to repeat biological sampling over time to look for different mechanisms of resistance. To this aim it is essential to obtain liquid and/or tissue biopsies to detect therapeutic targets, in particular for the analysis of different genomic alterations. This review discusses the mechanisms of resistance to therapeutics targeting genomic alterations in ALK as well as the advantages and the limitations of liquid biopsies for their identification.

Shallow Whole-Genome Sequencing from Plasma Identifies FGFR1 Amplified Breast Cancers and Predicts Overall Survival

Background: Focal amplification of fibroblast growth factor receptor 1 (FGFR1) defines a subgroup of breast cancers with poor prognosis and high risk of recurrence. We sought to demonstrate the potential of circulating cell-free DNA (cfDNA) analysis to evaluate FGFR1 copy numbers from a cohort of 100 metastatic breast cancer (mBC) patients. Methods: Formalin-fixed paraffin-embedded (FFPE) tissue samples were screened for FGFR1 amplification by FISH, and positive cases were confirmed with a microarray platform (Oncoscan^TM). Subsequently, cfDNA was evaluated by two approaches, i.e., mFAST-SeqS and shallow whole-genome sequencing (sWGS), to estimate the circulating tumor DNA (ctDNA) allele fraction (AF) and to evaluate the FGFR1 status. Results: Tissue-based analyses identified FGFR1 amplifications in 20/100 tumors. All cases with a ctDNA AF above 3% (n = 12) showed concordance for FGFR1 status between tissue and cfDNA. In one case, we were able to detect a high-level FGFR1 amplification, although the ctDNA AF was below 1%. Furthermore, high levels of ctDNA indicated an association with unfavorable prognosis based on overall survival. Conclusions: Screening for FGFR1 amplification in ctDNA might represent a viable strategy to identify patients eligible for treatment by FGFR inhibition, and mBC ctDNA levels might be used for the evaluation of prognosis in clinical drug trials.

Innovating Computational Biology and Intelligent Medicine: ICIBM 2019 Special Issue

The International Association for Intelligent Biology and Medicine (IAIBM) is a nonprofit organization that promotes intelligent biology and medical science. It hosts an annual International Conference on Intelligent Biology and Medicine (ICIBM), which was established in 2012. The ICIBM 2019 was held from 9 to 11 June 2019 in Columbus, Ohio, USA. Out of the 105 original research manuscripts submitted to the conference, 18 were selected for publication in a Special Issue in Genes. The topics of the selected manuscripts cover a wide range of current topics in biomedical research including cancer informatics, transcriptomic, computational algorithms, visualization and tools, deep learning, and microbiome research. In this editorial, we briefly introduce each of the manuscripts and discuss their contribution to the advance of science and technology.