Multiscale heterogeneity in gastric adenocarcinoma evolution is an obstacle to precision medicine

Abstract Background Cancer is a somatic evolutionary disease and adenocarcinomas of the stomach and gastroesophageal junction (GC) may serve as a two-dimensional model of cancer expansion, in which tumor subclones are not evenly mixed during tumor progression but rather spatially separated and diversified. We hypothesize that precision medicine efforts are compromised when clinical decisions are based on a single-sample analysis, which ignores the mechanisms of cancer evolution and resulting intratumoral heterogeneity. Using multiregional whole-exome sequencing, we investigated the effect of somatic evolution on intratumoral heterogeneity aiming to shed light on the evolutionary biology of GC. Methods The study comprised a prospective discovery cohort of 9 and a validation cohort of 463 GCs. Multiregional whole-exome sequencing was performed using samples form 45 primary tumors and 3 lymph node metastases (range 3–10 tumor samples/patient) of the discovery cohort. Results In total, the discovery cohort harbored 16,537 non-synonymous mutations. Intratumoral heterogeneity of somatic mutations and copy number variants were present in all tumors of the discovery cohort. Of the non-synonymous mutations, 53–91% were not present in each patient’s sample; 399 genes harbored 2–4 different non-synonymous mutations in the same patient; 175 genes showed copy number variations, the majority being heterogeneous, including CD274 (PD-L1). Multi-sample tree-based analyses provided evidence for branched evolution being most complex in a microsatellite instable GC. The analysis of the mode of evolution showed a high degree of heterogeneity in deviation from neutrality within each tumor. We found evidence of parallel evolution and evolutionary trajectories: different mutations of SMAD4 aligned with different subclones and were found only in TP53 mutant GCs. Conclusions Neutral and non-neutral somatic evolution shape the mutational landscape in GC along its lateral expansions. It leads to complex spatial intratumoral heterogeneity, where lymph node metastases may stem from different areas of the primary tumor, synchronously. Our findings may have profound effects on future patient management. They illustrate the risk of mis-interpreting tumor genetics based on single-sample analysis and open new avenues for an evolutionary classification of GC, i.e., the discovery of distinct evolutionary trajectories which can be utilized for precision medicine.

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Multiscale heterogeneity in gastric adenocarcinoma evolution is an obstacle to precision medicine

10.21203/rs.3.rs-62554/v2 ◽

2020 ◽

Author(s):

Christoph Röcken ◽

Anu Amallraja ◽

Christine Halske ◽

Luka Opasic ◽

Arne Traulsen ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Copy Number ◽

Validation Cohort ◽

Intratumoral Heterogeneity ◽

Discovery Cohort ◽

Clinical Prognosis ◽

Synonymous Mutations ◽

Somatic Evolution ◽

Whole Exome

Abstract Purpose: Cancer is a somatic evolutionary disease. Using multiregional whole exome sequencing, we tested the effect of somatic evolution on intratumoral heterogeneity and its putative clinical and biological implications in adenocarcinomas of the stomach and gastroesophageal junction (GC). Patients and Methods: The study comprised a prospective discovery cohort of 9 and a validation cohort of 463 GCs. Multiregional whole-exome sequencing was done using 48 tumor samples (range: 3-10 tumor samples/patient) of the discovery cohort.Results: In total, the discovery cohort harbored 16,537 non-synonymous mutations (mutations/sample: median n=159; mutations/patient: median n=369). Intratumoral heterogeneity of somatic mutations and copy number variants were present in all tumors of the discovery cohort. 53-91% of the non-synonymous mutations were not present in each patient’s sample; 399 genes harbored 2-4 different non-synonymous mutations in the same patient; 175 genes showed copy number variations, the majority being heterogeneous, including CD274 (PD-L1). Multi-sample tree-based analyses provided evidence for branched evolution being most complex in a microsatellite instable GC. The analysis of the mode of evolution showed a high degree of heterogeneity in deviation from neutrality within each tumor. Studies on the validation cohort showed that the subclonal loss of SMAD4 is an independent predictor for poor patient outcome in Caucasian patients.Conclusions: Neutral and non-neutral somatic evolution shape the mutational landscape in GC. It leads to complex spatial intratumoral heterogeneity and may have profound effects on patient management. It provides crucial information for an individualized understanding of clinical prognosis and therapeutic options in GC patients.

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Multiscale heterogeneity in gastric adenocarcinoma evolution is an obstacle to precision medicine

10.21203/rs.3.rs-62554/v1 ◽

2020 ◽

Author(s):

Christoph Röcken ◽

Anu Amallraja ◽

Christine Halske ◽

Luka Opasic ◽

Arne Traulsen ◽

...

Keyword(s):

Exome Sequencing ◽

Copy Number ◽

Validation Cohort ◽

Gastroesophageal Junction ◽

Copy Number Variations ◽

Intratumoral Heterogeneity ◽

Discovery Cohort ◽

Clinical Prognosis ◽

Synonymous Mutations ◽

Somatic Evolution

Abstract Background: Cancer is a somatic evolutionary disease, which adapts to environmental cues based on genetic constraints. Using multiregional exome sequencing, we tested the effect of somatic evolution on intratumoral heterogeneity and its putative clinical implications in adenocarcinomas of the stomach and gastroesophageal junction (GC). Methods: The study comprised a prospective discovery cohort of 9 and a validation cohort of 487 GCs. Multiregional whole-exome sequencing was done using 48 tumor samples (range: 3-10 tumor samples/patient) of the discovery cohort.Results: In total, the discovery cohort harbored 16,537 non-synonymous mutations (mutations/sample: median n=159; mutations/patient: median n=369). Intratumoral heterogeneity of somatic mutations and copy number variants were present in all tumors of the discovery cohort. 53-91% of the non-synonymous mutations were not present in each patient’s sample; 399 genes harbored 2-4 different non-synonymous mutations in the same patient; 175 genes showed copy number variations, the majority being heterogeneous, including CD274 (PD-L1). Phylogenetic analyses provided evidence for branched evolution being the most complex in a microsatellite instable GC. The analysis of the mode of evolution showed a high degree of heterogeneity in deviation from neutrality within each tumor. Studies on the validation cohort showed that the subclonal loss of SMAD4 is an independent predictor for poor patient outcome.Conclusions: Neutral and non-neutral somatic evolution shape the mutational landscape in GC. It leads to complex spatial intratumoral heterogeneity and may have profound effects on patient management. It provides crucial information for an individualized understanding of clinical prognosis and therapeutic options in GC patients.

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Copy number signatures predict chromothripsis and clinical outcomes in newly diagnosed multiple myeloma

Nature Communications ◽

10.1038/s41467-021-25469-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Kylee H. Maclachlan ◽

Even H. Rustad ◽

Andriy Derkach ◽

Binbin Zheng-Lin ◽

Venkata Yellapantula ◽

...

Keyword(s):

Multiple Myeloma ◽

Copy Number ◽

Prognostic Impact ◽

Newly Diagnosed ◽

Flexible Tool ◽

Whole Exome ◽

Hematological Cancers ◽

Relationship Of ◽

The Relationship ◽

Validation Series

AbstractChromothripsis is detectable in 20–30% of newly diagnosed multiple myeloma (NDMM) patients and is emerging as a new independent adverse prognostic factor. In this study we interrogate 752 NDMM patients using whole genome sequencing (WGS) to investigate the relationship of copy number (CN) signatures to chromothripsis and show they are highly associated. CN signatures are highly predictive of the presence of chromothripsis (AUC = 0.90) and can be used identify its adverse prognostic impact. The ability of CN signatures to predict the presence of chromothripsis is confirmed in a validation series of WGS comprised of 235 hematological cancers (AUC = 0.97) and an independent series of 34 NDMM (AUC = 0.87). We show that CN signatures can also be derived from whole exome data (WES) and using 677 cases from the same series of NDMM, we are able to predict both the presence of chromothripsis (AUC = 0.82) and its adverse prognostic impact. CN signatures constitute a flexible tool to identify the presence of chromothripsis and is applicable to WES and WGS data.

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Overexpression of Replication-Dependent Histone Signifies a Subset of Dedifferentiated Liposarcoma with Increased Aggressiveness

Cancers ◽

10.3390/cancers13133122 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3122

Author(s):

Yongjin Yoo ◽

Sang-Yoon Park ◽

Eun Byeol Jo ◽

Minji Choi ◽

Kyo Won Lee ◽

...

Keyword(s):

Copy Number ◽

Fold Change ◽

High Grade ◽

Rna Seq ◽

Fat Tissue ◽

Normal Tissues ◽

Whole Exome ◽

Well Differentiated ◽

Genetic Signatures ◽

Subtype Differences

Liposarcoma (LPS) is an adult soft tissue malignancy that arises from fat tissue, where well-differentiated (WD) and dedifferentiated (DD) forms are the most common. DDLPS represents the progression of WDLPS into a more aggressive high-grade and metastatic form. Although a few DNA copy-number amplifications are known to be specifically found in WD- or DDLPS, systematic genetic differences that signify subtype determination between WDLPS and DDLPS remain unclear. Here, we profiled the genome and transcriptome of 38 LPS tumors to uncover the genetic signatures of subtype differences. Replication-dependent histone (RD-HIST) mRNAs were highly elevated and their regulation was disrupted in a subset of DDLPS, increasing cellular histone molecule levels, as measured using RNA-seq (the averaged fold change of 53 RD-HIST genes between the DD and WD samples was 10.9) and immunohistochemistry. The change was not observed in normal tissues. Integrated whole-exome sequencing, RNA-seq, and methylation analyses revealed that the overexpressed HMGA2 (the fold change between DD and WD samples was 7.3) was responsible for the increased RD-HIST level, leading to aberrant cell proliferation. Therefore, HMGA2-mediated elevation of RD-HISTs were crucial events in determining the aggressiveness of DDLPS, which may serve as a biomarker for prognosis prediction for liposarcoma patients.

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Genomic alterations caused by HPV integration in a cohort of Chinese endocervical adenocarcinomas

Cancer Gene Therapy ◽

10.1038/s41417-020-00283-4 ◽

2021 ◽

Author(s):

Wenhui Li ◽

Wanjun Lei ◽

Xiaopei Chao ◽

Xiaochen Song ◽

Yalan Bi ◽

...

Keyword(s):

Copy Number ◽

Somatic Mutations ◽

Hpv Infection ◽

Copy Number Variations ◽

Cervical Adenocarcinoma ◽

Structural Variations ◽

Driver Genes ◽

Genetic Changes ◽

Genomic Changes ◽

Whole Exome

AbstractThe association between human papillomavirus (HPV) integration and relevant genomic changes in uterine cervical adenocarcinoma is poorly understood. This study is to depict the genomic mutational landscape in a cohort of 20 patients. HPV+ and HPV− groups were defined as patients with and without HPV integration in the host genome. The genetic changes between these two groups were described and compared by whole-genome sequencing (WGS) and whole-exome sequencing (WES). WGS identified 2916 copy number variations and 743 structural variations. WES identified 6113 somatic mutations, with a mutational burden of 2.4 mutations/Mb. Six genes were predicted as driver genes: PIK3CA, KRAS, TRAPPC12, NDN, GOLGA6L4 and BAIAP3. PIK3CA, NDN, GOLGA6L4, and BAIAP3 were recognized as significantly mutated genes (SMGs). HPV was detected in 95% (19/20) of patients with cervical adenocarcinoma, 7 of whom (36.8%) had HPV integration (HPV+ group). In total, 1036 genes with somatic mutations were confirmed in the HPV+ group, while 289 genes with somatic mutations were confirmed in the group without HPV integration (HPV− group); only 2.1% were shared between the two groups. In the HPV+ group, GOLGA6L4 and BAIAP3 were confirmed as SMGs, while PIK3CA, NDN, KRAS, FUT1, and GOLGA6L64 were identified in the HPV− group. ZDHHC3, PKD1P1, and TGIF2 showed copy number amplifications after HPV integration. In addition, the HPV+ group had significantly more neoantigens. HPV integration rather than HPV infection results in different genomic changes in cervical adenocarcinoma.

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Whole-exome sequencing reveals potential germline and somatic mutations in 60 malignant ovarian germ cell tumors

Biology of Reproduction ◽

10.1093/biolre/ioab052 ◽

2021 ◽

Author(s):

Juan Chen ◽

Yan Li ◽

Jianlei Wu ◽

Yakun Liu ◽

Shan Kang

Keyword(s):

Germ Cell ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Peripheral Blood ◽

Copy Number ◽

Somatic Mutations ◽

Germ Cell Tumors ◽

Germline Mutations ◽

Deletion Region ◽

Whole Exome

Abstract Background Malignant ovarian germ cell tumors (MOGCTs) are rare and heterogeneous ovary tumors. We aimed to identify potential germline mutations and somatic mutations in MOGCTs by whole-exome sequencing. Methods The peripheral blood and tumor samples from these patients were used to identify germline mutations and somatic mutations, respectively. For those genes corresponding to copy number alterations (CNA) deletion and duplication region, functional annotation of was performed. Immunohistochemistry was performed to evaluate the expression of mutated genes corresponding to CNA deletion region. Results In peripheral blood, copy number loss and gain were mostly found in yolk sac tumors (YST). Moreover, POU5F1 was the most significant mutated gene with mutation frequency > 10% in both CNA deletion and duplication region. In addition, strong cytoplasm staining of POU5F1 (corresponding to CNA deletion region) was found in 2 YST and nuclear staining in 2 dysgerminomas (DG) tumor samples. Genes corresponding to CNA deletion region were significantly enriched in the signaling pathway of regulating pluripotency of stem cells. In addition, genes corresponding to CNA duplication region were significantly enriched in the signaling pathways of RIG-I-like receptor, Toll-like receptor, NF-kappa B and Jak–STAT. KRT4, RPL14, PCSK6, PABPC3 and SARM1 mutations were detected in both peripheral blood and tumor samples. Conclusions Identification of potential germline mutations and somatic mutations in MOGCTs may provide a new field in understanding the genetic feature of the rare biological tumor type in the ovary.

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Novel Recurrent Altered Genes in Chinese Patients With Anaplastic Thyroid Cancer

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgab014 ◽

2021 ◽

Author(s):

Lingyun Zhang ◽

Zhixiang Ren ◽

Zhengzheng Su ◽

Yang Liu ◽

Tian Yang ◽

...

Keyword(s):

Thyroid Cancer ◽

Copy Number ◽

Treatment Strategies ◽

Gene Mutations ◽

Anaplastic Thyroid Cancer ◽

Chinese Patients ◽

Driver Gene ◽

Phosphatidylinositol 3 Kinase ◽

Entire Cohort ◽

Whole Exome

Abstract Background Anaplastic thyroid cancer (ATC) is a rare but lethal malignancy, and few systematic investigations on genomic profiles of ATC have been performed in Chinese patients. Methods Fifty-four ATC patients in West China Hospital between 2010 to 2020 were retrospectively analyzed, while 29 patients with available samples were sequenced by whole-exome sequencing (WES). The associations between genomic alterations and clinical characteristics were statistically evaluated. Results The median overall survival was 3.0 months in the entire cohort, which was impacted by multiple clinical features, including age, tumor size, and different treatment strategies. In the WES cohort, totally 797 nonsilent mutations were detected; the most frequently altered genes were TP53 (48%), BRAF (24%), PIK3CA (24%), and TERT promoter (21%). Although these mutations have been well-reported in previous studies, ethnic specificity was exhibited in terms of mutation frequency. Moreover, several novel significantly mutated genes were identified including RBM15 (17%), NOTCH2NL (14%), CTNNA3 (10%), and KATNAL2 (10%). WES-based copy number alteration analysis also revealed a high frequent gain of NOTCH2NL (41%), which induced its increased expression. Gene mutations and copy number alterations were enriched in phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin (mTOR), NOTCH, and WNT pathways. Conclusions This study reveals shared and ethnicity-specific genomic profiles of ATC in Chinese patients and suggests NOTCH2NL may act as a novel candidate driver gene for ATC tumorigenesis.

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Somatic evolution in non-neoplastic IBD-affected colon

10.1101/832014 ◽

2019 ◽

Author(s):

Sigurgeir Olafsson ◽

Rebecca E. McIntyre ◽

Tim Coorens ◽

Timothy Butler ◽

Hyunchul Jung ◽

...

Keyword(s):

Chronic Inflammatory Disease ◽

Interleukin 17 ◽

Normal Colon ◽

Synonymous Mutations ◽

Somatic Evolution ◽

Colonic Crypts ◽

Increased Risk ◽

Inflammatory Bowel ◽

Selection Mechanisms ◽

Mutational Processes

Summary paragraphInflammatory bowel disease (IBD) is a chronic inflammatory disease associated with increased risk of gastrointestinal cancers. Here, we whole-genome sequenced 447 colonic crypts from 46 IBD patients, and compared these to 412 crypts from 41 non-IBD controls. The average mutation rate of affected colonic epithelial cells is 2.4-fold that of healthy colon and this increase is mostly driven by acceleration of mutational processes ubiquitously observed in normal colon. In contrast to the normal colon, where clonal expansions outside the confines of the crypt are rare, we observed widespread millimeter-scale clonal expansions. We discovered non-synonymous mutations in ARID1A, FBXW7, PIGR and ZC3H12A, and genes in the interleukin 17 and Toll-like receptor pathways, under positive selection in IBD. These results suggest distinct selection mechanisms in the colitis-affected colon and that somatic mutations potentially play a causal role in IBD pathogenesis.

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Integrated proteogenomic analysis of metastatic thoracic tumors identifies APOBEC mutagenesis and copy number alterations as drivers of proteogenomic tumor evolution and heterogeneity

10.1101/301390 ◽

2018 ◽

Author(s):

Nitin Roper ◽

Shaojian Gao ◽

Tapan K. Maity ◽

A. Rouf Banday ◽

Xu Zhang ◽

...

Keyword(s):

Copy Number ◽

Thymic Carcinoma ◽

Patient Specific ◽

Tumor Evolution ◽

Copy Number Alterations ◽

Immune Microenvironment ◽

Mutation Status ◽

Whole Exome ◽

Rapid Autopsy ◽

Insight Into

ABSTRACTElucidation of the proteogenomic evolution of metastatic tumors may offer insight into the poor prognosis of patients harboring metastatic disease. We performed whole-exome and transcriptome sequencing, copy number alterations (CNA) and mass spectrometry-based quantitative proteomics of 37 lung adenocarcinoma (LUAD) and thymic carcinoma (TC) metastases obtained by rapid autopsy and found evidence of patient-specific, multi-dimensional heterogeneity. Extreme mutational heterogeneity was evident in a subset of patients whose tumors showed increased APOBEC-signature mutations and expression of APOBEC3 region transcripts compared to patients with lesser mutational heterogeneity. TP53 mutation status was associated with APOBEC hypermutators in our cohort and in three independent LUAD datasets. In a thymic carcinoma patient, extreme heterogeneity and increased APOBEC3AB expression was associated with a high-risk germline APOBEC3AB variant allele. Patients with CNA occurring late in tumor evolution had corresponding changes in gene expression and protein abundance indicating genomic instability as a mechanism of downstream transcriptomic and proteomic heterogeneity between metastases. Across all tumors, proteomic heterogeneity was greater than copy number and transcriptomic heterogeneity. Enrichment of interferon pathways was evident both in the transcriptome and proteome of the tumors enriched for APOBEC mutagenesis despite a heterogeneous immune microenvironment across metastases suggesting a role for the immune microenvironment in the expression of APOBEC transcripts and generation of mutational heterogeneity. The evolving, heterogeneous nature of LUAD and TC, through APOBEC-mutagenesis and CNA illustrate the challenges facing treatment outcomes.

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Evolutionary Trajectories toward Ceftazidime-Avibactam Resistance in Klebsiella pneumoniae Clinical Isolates

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00574-21 ◽

2021 ◽

Author(s):

Alessandra Carattoli ◽

Gabriele Arcari ◽

Giulia Bibbolino ◽

Federica Sacco ◽

Dario Tomolillo ◽

...

Keyword(s):

High Risk ◽

Klebsiella Pneumoniae ◽

Copy Number ◽

Residual Activity ◽

Gene Copy Number ◽

Resistance Mechanisms ◽

University Hospital ◽

Gene Copy ◽

Carbapenemase Gene ◽

Evolutionary Trajectories

From January 2019 to April 2020, 32 KPC-producing, ceftazidime-avibactam (CZA) resistant Klebsiella pneumoniae strains were isolated in a university hospital in Rome, Italy. These strains belonged to the ST512, ST101 and ST307 high-risk clones. Nine different CZA-resistant KPC-3 protein variants were identified, five of them never previously reported (KPC-66 to KPC-70). Among them, KPC-31, KPC-39, KPC-49, KPC-66, KP-68, KPC-69 and KPC-70 showed amino acid substitutions, insertions and deletions in the Ω loop of the protein. KPC-29 has the duplication, while the novel KPC-67 has the triplication of the KDD triplet in the 270-loop of the protein. Genomics performed on contemporary resistant and susceptible clones underlined that those novel mutations emerged in bla KPC-3 genes located on conserved plasmids: in ST512, all bla KPC-3 mutant genes were located in pKpQIL plasmids, while the three novel bla KPC-3 mutants identified in ST101 were on FIIk-FIA(HI1)-R plasmids. Selection also promoted multiplication of the carbapenemase gene copy number by transposition, recombination, and fusion of resident plasmids. When expressed in Escherichia coli recipient cells cloned in the high-copy number pTOPO vector, the Ω loop mutated variants showed CZA-resistant phenotype associated with susceptibility to carbapenems, while KPC variants with insertions in the 270-loop showed residual activity on carbapenems. The investigation of CZA-resistance mechanisms offered the unique opportunity to study vertical, horizontal, and oblique evolutionary trajectories of K. pneumoniae high-risk clones.

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