Inactivation of CDK12 Delineates a Distinct Immunogenic Class of Advanced Prostate Cancer.

Using integrative genomic analysis of 360 metastatic castration-resistant prostate cancer (mCRPC) samples, we identified a novel subtype of prostate cancer typified by biallelic loss of CDK12 that is mutually exclusive with tumors driven by DNA repair deficiency, ETS fusions, and SPOP mutations. CDK12 loss is enriched in mCRPC relative to clinically localized disease and characterized by focal tandem duplications (FTDs) that lead to increased gene fusions and marked differential gene expression. FTDs associated with CDK12 loss result in highly recurrent gains at loci of genes involved in the cell cycle and DNA replication. CDK12 mutant cases are baseline diploid and do not exhibit DNA mutational signatures linked to defects in homologous recombination. CDK12 mutant cases are associated with elevated neoantigen burden ensuing from fusion-induced chimeric open reading frames and increased tumor T cell infiltration/clonal expansion. CDK12 inactivation thereby defines a distinct class of mCRPC that may benefit from immune checkpoint immunotherapy.

Integrative clinical genomics of advanced prostate cancer.

Toward development of a precision medicine framework for metastatic, castration-resistant prostate cancer (mCRPC), we established a multi-institutional clinical sequencing infrastructure to conduct prospective whole-exome and transcriptome sequencing of bone or soft tissue tumor biopsies from a cohort of 150 mCRPC affected individuals. Aberrations of AR, ETS genes, TP53, and PTEN were frequent (40%-60% of cases), with TP53 and AR alterations enriched in mCRPC compared to primary prostate cancer. We identified new genomic alterations in PIK3CA/B, R-spondin, BRAF/RAF1, APC, ß-catenin, and ZBTB16/PLZF. Moreover, aberrations of BRCA2, BRCA1, and ATM were observed at substantially higher frequencies (19.3% overall) compared to those in primary prostate cancers. 89% of affected individuals harbored a clinically actionable aberration, including 62.7% with aberrations in AR, 65% in other cancer-related genes, and 8% with actionable pathogenic germline alterations. This cohort study provides clinically actionable information that could impact treatment decisions for these affected individuals.

Expressed pseudogenes in the transcriptional landscape of human cancers.

Pseudogene transcripts can provide a novel tier of gene regulation through generation of endogenous siRNAs or miRNA-binding sites. Characterization of pseudogene expression, however, has remained confined to anecdotal observations due to analytical challenges posed by the extremely close sequence similarity with their counterpart coding genes. Here, we describe a systematic analysis of pseudogene "transcription" from an RNA-Seq resource of 293 samples, representing 13 cancer and normal tissue types, and observe a surprisingly prevalent, genome-wide expression of pseudogenes that could be categorized as ubiquitously expressed or lineage and/or cancer specific. Further, we explore disease subtype specificity and functions of selected expressed pseudogenes. Taken together, we provide evidence that transcribed pseudogenes are a significant contributor to the transcriptional landscape of cells and are positioned to play significant roles in cellular differentiation and cancer progression, especially in light of the recently described ceRNA networks. Our work provides a transcriptome resource that enables high-throughput analyses of pseudogene expression.

Distinct structural classes of activating FOXA1 alterations in advanced prostate cancer.

ABTRACT: Forkhead box A1 (FOXA1) is a pioneer transcription factor that is essential for the normal development of several endoderm-derived organs, including the prostate gland1,2. FOXA1 is frequently mutated in hormone-receptor-driven prostate, breast, bladder and salivary-gland tumours3-8. However, it is unclear how FOXA1 alterations affect the development of cancer, and FOXA1 has previously been ascribed both tumour-suppressive9-11 and oncogenic12-14 roles. Here we assemble an aggregate cohort of 1,546 prostate cancers and show that FOXA1 alterations fall into three structural classes that diverge in clinical incidence and genetic co-alteration profiles, with a collective prevalence of 35%. Class-1 activating mutations originate in early prostate cancer without alterations in ETS or SPOP, selectively recur within the wing-2 region of the DNA-binding forkhead domain, enable enhanced chromatin mobility and binding frequency, and strongly transactivate a luminal androgen-receptor program of prostate oncogenesis. By contrast, class-2 activating mutations are acquired in metastatic prostate cancers, truncate the C-terminal domain of FOXA1, enable dominant chromatin binding by increasing DNA affinity and-through TLE3 inactivation-promote metastasis driven by the WNT pathway. Finally, class-3 genomic rearrangements are enriched in metastatic prostate cancers, consist of duplications and translocations within the FOXA1 locus, and structurally reposition a conserved regulatory element-herein denoted FOXA1 mastermind (FOXMIND)-to drive overexpression of FOXA1 or other oncogenes. Our study reaffirms the central role of FOXA1 in mediating oncogenesis driven by the androgen receptor, and provides mechanistic insights into how the classes of FOXA1 alteration promote the initiation and/or metastatic progression of prostate cancer. These results have direct implications for understanding the pathobiology of other hormone-receptor-driven cancers and rationalize the co-targeting of FOXA1 activity in therapeutic strategies.

Integrative clinical genomics of metastatic cancer.

Metastasis is the primary cause of cancer-related deaths. Although The Cancer Genome Atlas has sequenced primary tumour types obtained from surgical resections, much less comprehensive molecular analysis is available from clinically acquired metastatic cancers. Here we perform whole-exome and -transcriptome sequencing of 500 adult patients with metastatic solid tumours of diverse lineage and biopsy site. The most prevalent genes somatically altered in metastatic cancer included TP53, CDKN2A, PTEN, PIK3CA, and RB1. Putative pathogenic germline variants were present in 12.2% of cases of which 75% were related to defects in DNA repair. RNA sequencing complemented DNA sequencing to identify gene fusions, pathway activation, and immune profiling. Our results show that integrative sequence analysis provides a clinically relevant, multi-dimensional view of the complex molecular landscape and microenvironment of metastatic cancers.

Characterization of the EZH2-MMSET histone methyltransferase regulatory axis in cancer.

Histone methyltransferases (HMTases), as chromatin modifiers, regulate the transcriptomic landscape in normal development as well in diseases such as cancer. Here, we molecularly order two HMTases, EZH2 and MMSET, that have established genetic links to oncogenesis. EZH2, which mediates histone H3K27 trimethylation and is associated with gene silencing, was shown to be coordinately expressed and function upstream of MMSET, which mediates H3K36 dimethylation and is associated with active transcription. We found that the EZH2-MMSET HMTase axis is coordinated by a microRNA network and that the oncogenic functions of EZH2 require MMSET activity. Together, these results suggest that the EZH2-MMSET HMTase axis coordinately functions as a master regulator of transcriptional repression, activation, and oncogenesis and may represent an attractive therapeutic target in cancer.

Characterizing reduced coverage regions through comparison of exome and genome sequencing data across 10 centers.

PURPOSE: As massively parallel sequencing is increasingly being used for clinical decision making, it has become critical to understand parameters that affect sequencing quality and to establish methods for measuring and reporting clinical sequencing standards. In this report, we propose a definition for reduced coverage regions and describe a set of standards for variant calling in clinical sequencing applications. METHODS: To enable sequencing centers to assess the regions of poor sequencing quality in their own data, we optimized and used a tool (ExCID) to identify reduced coverage loci within genes or regions of particular interest. We used this framework to examine sequencing data from 500 patients generated in 10 projects at sequencing centers in the National Human Genome Research Institute/National Cancer Institute Clinical Sequencing Exploratory Research Consortium. RESULTS: This approach identified reduced coverage regions in clinically relevant genes, including known clinically relevant loci that were uniquely missed at individual centers, in multiple centers, and in all centers. CONCLUSION: This report provides a process road map for clinical sequencing centers looking to perform similar analyses on their data.

The mutational landscape of lethal castration-resistant prostate cancer.

Characterization of the prostate cancer transcriptome and genome has identified chromosomal rearrangements and copy number gains and losses, including ETS gene family fusions, PTEN loss and androgen receptor (AR) amplification, which drive prostate cancer development and progression to lethal, metastatic castration-resistant prostate cancer (CRPC). However, less is known about the role of mutations. Here we sequenced the exomes of 50 lethal, heavily pre-treated metastatic CRPCs obtained at rapid autopsy (including three different foci from the same patient) and 11 treatment-naive, high-grade localized prostate cancers. We identified low overall mutation rates even in heavily treated CRPCs (2.00 per megabase) and confirmed the monoclonal origin of lethal CRPC. Integrating exome copy number analysis identified disruptions of CHD1 that define a subtype of ETS gene family fusion-negative prostate cancer. Similarly, we demonstrate that ETS2, which is deleted in approximately one-third of CRPCs (commonly through TMPRSS2:ERG fusions), is also deregulated through mutation. Furthermore, we identified recurrent mutations in multiple chromatin- and histone-modifying genes, including MLL2 (mutated in 8.6% of prostate cancers), and demonstrate interaction of the MLL complex with the AR, which is required for AR-mediated signalling. We also identified novel recurrent mutations in the AR collaborating factor FOXA1, which is mutated in 5 of 147 (3.4%) prostate cancers (both untreated localized prostate cancer and CRPC), and showed that mutated FOXA1 represses androgen signalling and increases tumour growth. Proteins that physically interact with the AR, such as the ERG gene fusion product, FOXA1, MLL2, UTX (also known as KDM6A) and ASXL1 were found to be mutated in CRPC. In summary, we describe the mutational landscape of a heavily treated metastatic cancer, identify novel mechanisms of AR signalling deregulated in prostate cancer, and prioritize candidates for future study.

Expression and Role of PAICS, a De Novo Purine Biosynthetic Gene in Prostate Cancer.

BACKGROUND: Our goal was to investigate de novo purine biosynthetic gene PAICS expression and evaluate its role in prostate cancer progression. METHODS: Next-generation sequencing, qRTPCR and immunoblot analysis revealed an elevated expression of a de novo purine biosynthetic gene, Phosphoribosylaminoimidazole Carboxylase, Phosphoribosylaminoimidazole Succinocarboxamide Synthetase (PAICS) in a progressive manner in prostate cancer. Functional analyses were performed using prostate cancer cell lines- DU145, PC3, LnCaP, and VCaP. The oncogenic properties of PAICS were studied both by transient and stable knockdown strategies, in vivo chicken chorioallantoic membrane (CAM) and murine xenograft models. Effect of BET bromodomain inhibitor JQ1 on the expression level of PAICS was also studied. RESULTS: Molecular staging of prostate cancer is important factor in effective diagnosis, prognosis and therapy. In this study, we identified a de novo purine biosynthetic gene; PAICS is overexpressed in PCa and its expression correlated with disease aggressiveness. Through several in vitro and in vivo functional studies, we show that PAICS is necessary for proliferation and invasion in prostate cancer cells. We identified JQ1, a BET bromodomain inhibitor previously implicated in regulating MYC expression and demonstrated role in prostate cancer, abrogates PAICS expression in several prostate cancer cells. Furthermore, we observe loss of MYC occupancy on PAICS promoter in presence of JQ1. CONCLUSIONS: Here, we report that evaluation of PAICS in prostate cancer progression and its role in prostate cancer cell proliferation and invasion and suggest it as a valid therapeutic target. We suggest JQ1, a BET-domain inhibitor, as possible therapeutic option in targeting PAICS in prostate cancer. Prostate 77:10-21, 2017. © 2016 Wiley Periodicals, Inc.

Primary urethral clear-cell adenocarcinoma: comprehensive analysis by surgical pathology, cytopathology, and next-generation sequencing.

Primary clear-cell adenocarcinoma of the urethra, a rare tumor that histomorphologically resembles clear-cell carcinoma of the female genital tract, occurs predominantly in women and is associated with a relatively poor prognosis. The histogenesis of this rare urethral neoplasm has not been completely resolved, but it is thought to arise from either müllerian rests or metaplastic urothelium. Herein, we present comprehensive surgical pathological and cytopathological findings from a patient with primary urethral clear-cell adenocarcinoma and describe next-generation sequencing results for this patient's unique tumor-the first such reported characterization of molecular aberrations in urethral clear-cell adenocarcinoma at the transcriptomic and genomic levels. Transcriptome analysis revealed novel gene fusion candidates, including ANKRD28-FNDC3B. Whole-exome analysis demonstrated focal copy number loss at the SMAD4 and ARID2 loci and 38 somatic mutations, including a truncating mutation in ATM and a novel nonsynonymous mutation in ALK.

Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression.

Multiple, complex molecular events characterize cancer development and progression. Deciphering the molecular networks that distinguish organ-confined disease from metastatic disease may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Although gene and protein expression have been extensively profiled in human tumours, little is known about the global metabolomic alterations that characterize neoplastic progression. Using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry, we profiled more than 1,126 metabolites across 262 clinical samples related to prostate cancer (42 tissues and 110 each of urine and plasma). These unbiased metabolomic profiles were able to distinguish benign prostate, clinically localized prostate cancer and metastatic disease. Sarcosine, an N-methyl derivative of the amino acid glycine, was identified as a differential metabolite that was highly increased during prostate cancer progression to metastasis and can be detected non-invasively in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells. Knockdown of glycine-N-methyl transferase, the enzyme that generates sarcosine from glycine, attenuated prostate cancer invasion. Addition of exogenous sarcosine or knockdown of the enzyme that leads to sarcosine degradation, sarcosine dehydrogenase, induced an invasive phenotype in benign prostate epithelial cells. Androgen receptor and the ERG gene fusion product coordinately regulate components of the sarcosine pathway. Here, by profiling the metabolomic alterations of prostate cancer progression, we reveal sarcosine as a potentially important metabolic intermediary of cancer cell invasion and aggressivity.

Integrative Clinical Sequencing in the Management of Refractory or Relapsed Cancer in Youth.

IMPORTANCE: Cancer is caused by a diverse array of somatic and germline genomic aberrations. Advances in genomic sequencing technologies have improved the ability to detect these molecular aberrations with greater sensitivity. However, integrating them into clinical management in an individualized manner has proven challenging. OBJECTIVE: To evaluate the use of integrative clinical sequencing and genetic counseling in the assessment and treatment of children and young adults with cancer. DESIGN, SETTING, AND PARTICIPANTS: Single-site, observational, consecutive case series (May 2012-October 2014) involving 102 children and young adults (mean age, 10.6 years; median age, 11.5 years, range, 0-22 years) with relapsed, refractory, or rare cancer. EXPOSURES: Participants underwent integrative clinical exome (tumor and germline DNA) and transcriptome (tumor RNA) sequencing and genetic counseling. Results were discussed by a precision medicine tumor board, which made recommendations to families and their physicians. MAIN OUTCOMES AND MEASURES: Proportion of patients with potentially actionable findings, results of clinical actions based on integrative clinical sequencing, and estimated proportion of patients or their families at risk of future cancer. RESULTS: Of the 104 screened patients, 102 enrolled with 91 (89%) having adequate tumor tissue to complete sequencing. Only the 91 patients were included in all calculations, including 28 (31%) with hematological malignancies and 63 (69%) with solid tumors. Forty-two patients (46%) had actionable findings that changed their cancer management: 15 of 28 (54%) with hematological malignancies and 27 of 63 (43%) with solid tumors. Individualized actions were taken in 23 of the 91 (25%) based on actionable integrative clinical sequencing findings, including change in treatment for 14 patients (15%) and genetic counseling for future risk for 9 patients (10%). Nine of 91 (10%) of the personalized clinical interventions resulted in ongoing partial clinical remission of 8 to 16 months or helped sustain complete clinical remission of 6 to 21 months. All 9 patients and families with actionable incidental genetic findings agreed to genetic counseling and screening. CONCLUSIONS AND RELEVANCE: In this single-center case series involving young patients with relapsed or refractory cancer, incorporation of integrative clinical sequencing data into clinical management was feasible, revealed potentially actionable findings in 46% of patients, and was associated with change in treatment and family genetic counseling for a small proportion of patients. The lack of a control group limited assessing whether better clinical outcomes resulted from this approach than outcomes that would have occurred with standard care.

Role of dutasteride in pre-clinical ETS fusion-positive prostate cancer models.

BACKGROUND: Androgens play a crucial role in prostate cancer, hence the androgenic pathway has become an important target of therapeutic intervention. Previously we discovered that gene fusions between the 5'-untranslated region of androgen regulated gene TMPRSS2 and the ETS transcription factor family members were present in a majority of the prostate cancer cases. The resulting aberrant overexpression of ETS genes drives tumor progression. METHODS: Here, we evaluated the expression levels of 5α-reductase isoenzymes in prostate cancer cell lines and tissues. We tested the effect of dutasteride, a 5α-reductase inhibitor, in TMPRSS2-ERG fusion-positive VCaP cell proliferation and cell invasion. We also evaluated the effect of dutasteride on the TMPRSS2-ERG fusion gene expression. Finally, we tested dutasteride alone or in combination with an anti-androgen in VCaP cell xenografts tumor model. RESULTS: Our data showed that 5α-reductase SRD5A1 and SRD5A3 isoenzymes that are responsible for the conversion of testosterone to DHT, are highly expressed in metastatic prostate cancer compared to benign and localized prostate cancer. Dutasteride treatment attenuated VCaP cell proliferation and invasion. VCaP cells pre-treated with dutasteride showed a reduction in ERG and PSA expression. In vivo studies demonstrated that dutasteride in combination with the anti-androgen bicalutamide significantly decreased tumor burden in VCaP cell xenograft model. CONCLUSIONS: Our findings suggest that dutasteride can inhibit ERG fusion-positive cell growth and in combination with anti-androgen, significantly reduce the tumor burden. Our study suggests that anti-androgens used in combination with dutasteride could synergistically augment the therapeutic efficacy in the treatment of ETS-positive prostate cancer.

Chimeric transcript discovery by paired-end transcriptome sequencing.

Recurrent gene fusions are a prevalent class of mutations arising from the juxtaposition of 2 distinct regions, which can generate novel functional transcripts that could serve as valuable therapeutic targets in cancer. Therefore, we aim to establish a sensitive, high-throughput methodology to comprehensively catalog functional gene fusions in cancer by evaluating a paired-end transcriptome sequencing strategy. Not only did a paired-end approach provide a greater dynamic range in comparison with single read based approaches, but it clearly distinguished the high-level "driving" gene fusions, such as BCR-ABL1 and TMPRSS2-ERG, from potential lower level "passenger" gene fusions. Also, the comprehensiveness of a paired-end approach enabled the discovery of 12 previously undescribed gene fusions in 4 commonly used cell lines that eluded previous approaches. Using the paired-end transcriptome sequencing approach, we observed read-through mRNA chimeras, tissue-type restricted chimeras, converging transcripts, diverging transcripts, and overlapping mRNA transcripts. Last, we successfully used paired-end transcriptome sequencing to detect previously undescribed ETS gene fusions in prostate tumors. Together, this study establishes a highly specific and sensitive approach for accurately and comprehensively cataloguing chimeras within a sample using paired-end transcriptome sequencing.

AGTR1 overexpression defines a subset of breast cancer and confers sensitivity to losartan, an AGTR1 antagonist.

Breast cancer patients have benefited from the use of targeted therapies directed at specific molecular alterations. To identify additional opportunities for targeted therapy, we searched for genes with marked overexpression in subsets of tumors across a panel of breast cancer profiling studies comprising 3,200 microarray experiments. In addition to prioritizing ERBB2, we found AGTR1, the angiotensin II receptor type I, to be markedly overexpressed in 10-20% of breast cancer cases across multiple independent patient cohorts. Validation experiments confirmed that AGTR1 is highly overexpressed, in several cases more than 100-fold. AGTR1 overexpression was restricted to estrogen receptor-positive tumors and was mutually exclusive with ERBB2 overexpression across all samples. Ectopic overexpression of AGTR1 in primary mammary epithelial cells, combined with angiotensin II stimulation, led to a highly invasive phenotype that was attenuated by the AGTR1 antagonist losartan. Similarly, losartan reduced tumor growth by 30% in AGTR1-positive breast cancer xenografts. Taken together, these observations indicate that marked AGTR1 overexpression defines a subpopulation of ER-positive, ERBB2-negative breast cancer that may benefit from targeted therapy with AGTR1 antagonists, such as losartan.

Assessment of Clinical Benefit of Integrative Genomic Profiling in Advanced Solid Tumors.

IMPORTANCE: Use of next-generation sequencing (NGS) to identify clinically actionable genomic targets has been incorporated into routine clinical practice in the management of advanced solid tumors; however, the clinical utility of this testing remains uncertain. OBJECTIVE: To determine which patients derived the greatest degree of clinical benefit from NGS profiling. DESIGN, SETTING, AND PARTICIPANTS: Patients in this cohort study underwent fresh tumor biopsy and blood sample collection for genomic profiling of paired tumor and normal DNA (whole-exome or targeted-exome capture with analysis of 1700 genes) and tumor transcriptome (RNA) sequencing. Somatic and germline genomic alterations were annotated and classified according to degree of clinical actionability. Results were returned to treating oncologists. Data were collected from May 1, 2011, to February 28, 2018, and analyzed from May 1, 2011, to April 30, 2020. MAIN OUTCOMES AND MEASURES: Patients' subsequent therapy and treatment response were extracted from the medical record to determine clinical benefit rate from NGS-directed therapy at 6 months and exceptional responses lasting 12 months or longer. RESULTS: During the study period, NGS was attempted on tumors from 1138 patients and was successful in 1015 (89.2%) (MET1000 cohort) (538 men [53.0%]; mean [SD] age, 57.7 [13.3] years). Potentially clinically actionable genomic alterations were discovered in 817 patients (80.5%). Of these, 132 patients (16.2%) received sequencing-directed therapy, and 49 had clinical benefit (37.1%). Exceptional responses were observed in 26 patients (19.7% of treated patients). Pathogenic germline variants (PGVs) were identified in 160 patients (15.8% of cohort), including 49 PGVs (4.8% of cohort) with therapeutic relevance. For 55 patients with carcinoma of unknown primary origin, NGS identified the primary site in 28 (50.9%), and sequencing-directed therapy in 13 patients resulted in clinical benefit in 7 instances (53.8%), including 5 exceptional responses. CONCLUSIONS AND RELEVANCE: The high rate of therapeutically relevant PGVs identified across diverse cancer types supports a recommendation for directed germline testing in all patients with advanced cancer. The high frequency of therapeutically relevant somatic and germline findings in patients with carcinoma of unknown primary origin and other rare cancers supports the use of comprehensive NGS profiling as a component of standard of care for these disease entities.

Fluorescence in situ hybridization study shows association of PTEN deletion with ERG rearrangement during prostate cancer progression.

The link between ERG rearrangement and PTEN (phosphatase and tensin homolog deleted on chromosome 10) deletion is unclear in prostate cancer progression. Using fluorescence in situ hybridization, we systematically validated the frequency and distribution of ERG and PTEN aberrations in a cohort of 73 benign prostate tissues, 59 high-grade prostatic intraepithelial neoplasia (HGPIN) foci, 281 localized prostate cancer and 47 androgen-independent metastatic prostate cancer patients. Overall, ERG rearrangement was present in 15% (5/33) of HGPIN, 45% (121/267) of localized cancers and 35% (15/43) of metastases. By contrast, PTEN deletion was identified in 9% (3/33) of HGPIN, 17% (42/251) of localized cancers and 54% (22/41) of metastases, of which 0%, 40% (17/42) and 45% (10/22) were homozygous, respectively. Concomitance of ERG rearrangement and PTEN deletion was observed in a subset of HGPIN. Significantly, association between PTEN deletion and ERG rearrangement was present both in localized cancers (P=0.0008) and metastases (P=0.02). Further, immunohistochemistry revealed significant correlation of decreased PTEN protein expression with PTEN genomic deletion both in localized and metastatic cancer. Of note, ERG aberration, but not PTEN deletion, was consistently identical both in localized cancer and adjacent HGPIN. Similarly, whereas all metastases (41/41, 100%) shared the same ERG status across multiple sites from the same patient, 5% (2/41) of cases showed discordance for PTEN deletion status across multiple sites. Collectively, our data support PTEN deletion as a late genetic event in human prostate cancer, presumably a 'second hit' after ERG rearrangement. PTEN deletion and ERG rearrangement may cooperate, but contribute at different stages, in prostate cancer progression.

Identification of novel MECOM gene fusion and personalized therapeutic targets through integrative clinical sequencing in secondary acute myeloid leukemia in a patient with severe congenital neutropenia: a case report and literature review.

Severe congenital neutropenia (SCN) is a rare hematologic disorder characterized by defective myelopoiesis and a high incidence of malignant transformation to myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). SCN patients who develop MDS/AML have excessive toxicities to traditional chemotherapy, and safer therapies are needed to improve overall survival in this population. In this report, we outline the use of a prospective integrative clinical sequencing trial (PEDS-MIONCOSEQ) in a patient with SCN and AML to help identify oncogenic targets for less toxic agents. Integrative sequencing identified two somatic cis-mutations in the colony stimulating factor 3 receptor (CSF3R) gene, a p.T640N mutation in the transmembrane region and a p.Q768* truncation mutation in the cytoplasmic domain. A somatic mutation p.H105Y, in the runt homology domain (RHD) of runt-related transcription factor 1 (RUNX1), was also identified. In addition, sequencing discovered a unique in-frame EIF4A2-MECOM (MDS1 and ectopic viral integration site 1 complex) chromosomal translocation with high MECOM expression. His mutations in CSF3R served as potential targets for tyrosine kinase inhibition and therefore provided an avenue to avoid more harmful therapy. This study highlights the utility of integrative clinical sequencing in SCN patients who develop leukemia and outlines a strategy on how to approach these patients in a future clinical sequencing trial to improve historically poor outcomes. A thorough review of leukemia in SCN and the role of CSF3R mutations in oncologic therapy are provided to support a new strategy on how to approach MDS/AML in SCN.