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ObjectiveEffective functional biomarkers that can be readily used in clinical practice to predict poly(ADP-ribose) polymerase inhibitor (PARPi) sensitivity are lacking. With the widespread adoption of PARPi maintenance therapy in ovarian cancer, particularly in patients with BRCA mutation or HR deficiencies, accurately identifying de novo or acquired resistance to PARPi has become critical in clinical practice. We investigated RAD51 immunohistochemistry (IHC) as a functional biomarker for predicting PARPi sensitivity in ovarian cancer.MethodsOvarian cancer patients who had received PARPi and had archival tissue samples prior to PARPi exposure (“pre-PARPi”) and/or after progression on PARPi (“post-PARPi”) were selected. RAD51 IHC expression was semi-quantitatively evaluated using the H-score in geminin (a G2/S phase marker)- and γH2AX (a DNA damage marker)-positive tissues. A RAD51 H-score of 20 was used as the cutoff value.ResultsIn total, 72 samples from 56 patients were analyzed. The median RAD51 H-score was 20 (range: 0–90) overall, 10 (0–190) in pre-PARPi samples (n = 34), and 25 (1–170) in post-PARPi samples (n = 19). Among patients with BRCA mutations, RAD51-low patients had better progression-free survival (PFS) after PARPi treatment than RAD51-high patients (P = 0.029). No difference was found in PFS with respect to the genomic scar score (P = 0.930). Analysis of matched pre- and post-PARPi samples collected from 15 patients indicated an increase in the RAD51 H-score upon progression on PARPi, particularly among pre-PARPi low-RAD51-expressing patients.ConclusionRAD51 is a potential functional IHC biomarker of de novo and acquired PARPi resistance in BRCA-mutated ovarian cancer and can be used to fine-tune ovarian cancer treatment.

Abstract Background Recurrent glioblastoma multiforme (GBM) is a highly aggressive primary malignant brain tumor that is resistant to existing treatments. Recently, we reported that activated autologous natural killer (NK) cell therapeutics induced a marked increase in survival of some patients with recurrent GBM. Methods To identify biomarkers that predict responsiveness to NK cell therapeutics, we examined immune profiles in tumor tissues using NanoString nCounter analysis and compared the profiles between 5 responders and 7 non-responders. Through a three-step data analysis, we identified three candidate biomarkers (TNFRSF18, TNFSF4, and IL12RB2) and performed validation with qRT-PCR. We also performed immunohistochemistry and a NK cell migration assay to assess the function of these genes. Results Responders had higher expression of many immune-signaling genes compared with non-responders, which suggests an immune-active tumor microenvironment in responders. The random forest model that identified TNFRSF18, TNFSF4, and IL12RB2 showed a 100% accuracy (95% CI 73.5–100%) for predicting the response to NK cell therapeutics. The expression levels of these three genes by qRT-PCR were highly correlated with the NanoString levels, with high Pearson’s correlation coefficients (0.419 (TNFRSF18), 0.700 (TNFSF4), and 0.502 (IL12RB2)); their prediction performance also showed 100% accuracy (95% CI 73.54–100%) by logistic regression modeling. We also demonstrated that these genes were related to cytotoxic T cell infiltration and NK cell migration in the tumor microenvironment. Conclusion We identified TNFRSF18, TNFSF4, and IL12RB2 as biomarkers that predict response to NK cell therapeutics in recurrent GBM, which might provide a new treatment strategy for this highly aggressive tumor.

Abstract Studies investigating the relationship between germline telomere length and the clinical characteristics of tumors are very limited. This study evaluated the relationship between germline telomere length and the clinical characteristics of neuroblastoma. In addition, a genome-wide association study (GWAS) was performed to investigate the genetic factors associated with germline telomere length. The germline telomere length of peripheral blood mononuclear cells from 186 patients with neuroblastoma was measured by quantitative polymerase chain reaction. The association between germline telomere length and clinical characteristics, including long-term survival, was investigated. For the GWAS, genotyping was performed with a high-density bead chip (Illumina, San Diego, CA, USA). After strict quality-control checks of the samples, an association analysis was conducted. The result showed that longer germline telomeres were significantly associated with longer event-free survival (P = 0.032). To identify significantly assocated genetic markers for germline telomere length, genome wide association analysis was performed. As a result, several single nucleotide polymorphisms located in HIVEP3, LRRTM4, ADGRV1, RAB30, and CHRNA4 genes were discovered. During gene-based analysis (VEGAS2 tool), the CNTN4 gene had the most significant association with germline telomere length (P = 1.0E−06). During gene ontology analysis, susceptible genes associated with germline telomere length were mainly distributed in neurite morphogenesis and neuron development. A longer germline telomere length is associated with favorable prognostic factors at diagnosis and eventually better event-free survival in patients with neuroblastoma. In addition, the GWAS demonstrated that genetic markers and genes related to germline telomere length are associated with neurite morphogenesis and neuron development. Further research with larger cohorts of patients and functional investigations are needed.

Background & Aims: Tumor necrosis factor alpha (TNFα) is considered a major tissue damage-promoting effector in Crohn’s disease (CD) pathogenesis. Patient-derived intestinal organoid (enteroid) recapitulates the disease-specific characteristics of the intestinal epithelium. This study aimed to evaluate the intestinal epithelial responses to TNFα in enteroids derived from healthy controls and compare them with those of CD patient-derived enteroids. Methods: Human enteroids derived from patients with CD and controls were treated with TNFα (30 ng/mL), and cell viability and gene expression patterns were evaluated. Results: TNFα induced MLKL-mediated necroptotic cell death, which was more pronounced in CD patient-derived enteroids than in control enteroids. Immunohistochemistry and RNA sequencing revealed that treatment with TNFα caused expansion of the intestinal stem cell (ISC) populations. However, expanded ISC subpopulations differed in control and CD patient-derived enteroids, with LGR5+ active ISCs in control enteroids and reserve ISCs, such as BMI1+ cells, in CD patient-derived enteroids. In single-cell RNA sequencing, LGR5+ ISC-enriched cell cluster showed strong expression of TNFRSF1B (TNFR2) and cyclooxygenase-prostaglandin E2 (PGE2) activation. In TNFα-treated CD patient-derived enteroids, exogenous PGE2 (10 nmol/L) induced the expansion of the LGR5+ ISC population and improved organoid-forming efficiency, viability, and wound healing. Conclusions: TNFα increases necroptosis of differentiated cells and induces the expansion of LGR5+ ISCs. In CD patient-derived enteroids, TNFα causes LGR5+ stem cell dysfunction (expansion failure), and exogenous PGE2 treatment restored the functions of LGR5+ stem cells. Therefore, PGE2 can be used to promote mucosal healing in patients with CD.

Abstract Background Young patients with colorectal cancer (CRC) exhibit poor prognoses compared to older patients due to the difficulty in early diagnosis and treatment. However, the underlying molecular characteristics are still unclear. Methods We conducted a comprehensive analysis of 49 CRC patients without hereditary CRC using the whole-exome and RNA sequencing with tumor and matched normal samples. A total of 594 TCGA samples and 4 patient-derived cells were utilized for validation. Results Consensus molecular subtype 4 (CMS4) (53.85%) and CMS2 (38.46%) were enriched in the young (≤ 40 years) and old (> 60 years) age groups, respectively. A CMS4-associated gene, platelet-derived growth factor receptor α (PDGFRA), was significantly upregulated in young patients with CRC (FC = 3.21, p = 0.0001) and was negatively correlated with age (p = 0.0001, R = − 0.526). Moreover, PDGFRA showed a positive co-expression with metastasis-related genes in young CRC patients. In vitro validation confirmed that young patient-derived cells (PDCs) showed an enriched expression of PDGFRA compared to old PDCs and a reduced proliferation rate by knockdown of PDGFRA. Furthermore, young CRC patients were more sensitive to regorafenib, a PDGFRA-targeting drug, than old CRC patients. Conclusions Our study suggests that CRC in young patients is associated with CMS4 and PDGFRA. In addition, PDGFRA may serve potential of novel therapeutic strategies and represent a predictive biomarker of response to regorafenib for young CRC patients.

BackgroundThe intestinal microenvironment directly determines the human T-cell receptor (TCR) repertoire. Despite its extreme diversity, TCR repertoire analysis may provide a better understanding of the immune system in patients with inflammatory bowel disease.MethodsTo investigate TCR repertoires in the intestinal mucosa, RNA sequencing was performed for inflamed and non-inflamed intestinal mucosa samples obtained from 13 patients with Crohn’s disease (CD) and healthy mucosa from nine non-IBD controls.ResultsThe gene expression frequency of the TCR repertoire showed a clear separation between inflamed mucosa of patients with CD and healthy mucosa of non-IBD controls in the hierarchical clustering heatmap. The richness of TCR repertoires measured by the Chao1 index did not show a significant difference among groups, whereas diversity measured by the D50 diversity index was decreased in the inflamed mucosa of CD patients. Rare/small TCR clonotypes occupied a large proportion of TCR repertoires in healthy mucosa of controls, whereas expanded clonotypes were common in inflamed mucosa of patients with CD. Segment usages of TRAV2, TRAV22, TRAV40, TRJ14, TRAJ51, TRBV1, TRBV21.1, and TRBJ1.5 were significantly decreased in CD patients. KEGG enrichment analysis identified the enrichment of several KEGG pathways, including inflammatory bowel disease (p = 0.0012), Th1 and Th2 cell differentiation (p = 0.0011), and intestinal immune network for IgA production (p = 0.0468).ConclusionsThe diversity of the TCR repertoire is reduced in inflamed mucosa of CD patients, which might contribute to intestinal inflammation.

Abstract Previous studies suggested that genetic, environmental factors and their interactions could affect body fat mass (BFM). However, studies describing these effects were performed at a single time point in a population. In this study, we investigated the interaction between genetic and environmental factors in affecting BFM and implicate the healthcare utilization of lifestyle modifications from a personalized and genomic perspective. We examined how nutritional intake or physical activity changes in the individuals affect BFM concerning the genetic composition. We conducted an observational study including 259 adult participants with single nucleotide polymorphism (SNP) genotyping and longitudinal lifestyle monitoring, including food consumption and physical activities, by following lifestyle modification guidance. The participants’ lifelog data on exercise and diet were collected through a wearable device for 3 months. Moreover, we measured anthropometric and serologic markers to monitor their potential changes through lifestyle modification. We examined the influence of genetic composition on body fat reduction induced by lifestyle changes using genetic risk scores (GRSs) of three phenotypes: GRS-carbohydrate (GRS-C), GRS-fat (GRS-F), and GRS-exercise (GRS-E). Our results showed that lifestyle modifications affected BFM more significantly in the high GRS class compared to the low GRS class, indicating the role of genetic factors affecting the efficiency of the lifestyle modification-induced BFM changes. Interestingly, the influence of exercise modification in the low GRS class with active lifestyle change was lower than that in the high GRS class with inactive lifestyle change (P = 0.022), suggesting the implication of genetic factors for efficient body fat control.

Due to the highly immunogenic nature of renal cell carcinoma (RCC), the tumor microenvironment (TME) is enriched with various innate and adaptive immune subsets. In particular, gamma-delta (γδ) T cells can act as potent attractive mediators of adoptive cell transfer immunotherapy because of their unique properties such as non-reliance on major histocompatibility complex expression, their ability to infiltrate human tumors and recognize tumor antigens, relative insensitivity to immune checkpoint molecules, and broad tumor cytotoxicity. Therefore, it is now critical to better characterize human γδ T-cell subsets and their mechanisms in RCCs, especially the stage of differentiation. In this study, we aimed to identify γδ T cells that might have adaptive responses against RCC progression. We characterized γδ T cells in peripheral blood and tumor-infiltrating lymphocytes (TILs) in freshly resected tumor specimens from 20 RCC patients. Furthermore, we performed a gene set enrichment analysis on RNA-sequencing data from The Cancer Genome Atlas (TCGA) derived from normal kidneys and RCC tumors to ascertain the association between γδ T-cell infiltration and anti-cancer immune activity. Notably, RCC-infiltrating CD3low Vγ9Vδ1 T cells with a terminally differentiated effector memory phenotype with up-regulated activation/exhaustion molecules were newly detected as predominant TILs, and the cytotoxic activity of these cells against RCC was confirmed in vitro. In an additional analysis of the TCGA RCC dataset, γδ T-cell enrichment scores correlated strongly with those for CTLs, Th1 cells, “exhausted” T cells, and M1 macrophages, suggesting active involvement of γδ T cells in anti-tumor rather than pro-tumor activity, and Vδ1 cells were more abundant than Vδ2 or Vδ3 cells in RCC tumor samples. Thus, we posit that Vγ9Vδ1 T cells may represent an excellent candidate for adoptive immunotherapy in RCC patients with a high risk of relapse after surgery.

Understanding the mechanisms that lead to lung adenocarcinoma metastasis is important for identifying new therapeutics. Here, the authors document the changes in the transcriptome of human lung adenocarcinoma using single-cell sequencing and link cancer cell signatures to immune cell dynamics.

IntroductionThe prognostic value of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in hepatocellular carcinoma (HCC) was established in previous reports. However, there is no evidence suggesting the prognostic value of transcriptomes associated with tumor FDG uptake in HCC. It was aimed to elucidate metabolic genes and functions associated with FDG uptake, followed by assessment of those prognostic value.MethodsSixty HCC patients with Edmondson–Steiner grade II were included. FDG PET/CT scans were performed before any treatment. RNA sequencing data were obtained from tumor and normal liver tissue. Associations between each metabolism-associated gene and tumor FDG uptake were investigated by Pearson correlation analyses. A novel score between glucose and lipid metabolism-associated gene expression was calculated. In The Cancer Genome Atlas Liver Hepatocellular Carcinoma dataset, the prognostic power of selected metabolism-associated genes and a novel score was evaluated for external validation.ResultsNine genes related to glycolysis and the HIF-1 signaling pathway showed positive correlations with tumor FDG uptake; 21 genes related to fatty acid metabolism and the PPAR signaling pathway demonstrated negative correlations. Seven potential biomarker genes, PFKFB4, ALDOA, EGLN3, EHHADH, GAPDH, HMGCS2, and ENO2 were identified. A metabolic gene expression balance score according to the dominance between glucose and lipid metabolism demonstrated good prognostic value in HCC.ConclusionsThe transcriptomic evidence of this study strongly supports the prognostic power of FDG PET/CT and indicates the potential usefulness of FDG PET/CT imaging biomarkers to select appropriate patients for metabolism-targeted therapy in HCC.

Abstract Background The immunogenomic changes triggered by concurrent chemoradiation therapy (CCRT), a standard neoadjuvant treatment for locally advanced esophageal squamous cell carcinoma (ESCC), are unknown. We aimed to analyze the early immunogenomic changes in ESCC induced by CCRT and to correlate them with clinical outcomes. Methods We collected biopsy samples from 40 patients with ESCC and the surgical candidates were treated with 5-fluorouracil (5-FU)/Cisplatin and concurrent radiation therapy. Endoscopic biopsy was performed before and after one treatment cycle of 5-FU/Cisplatin and 5 to 18 fractions of radiation. We analyzed immunogenomic changes using paired whole-exome sequencing (n = 29) and paired whole-transcriptome sequencing (WTS, n = 23). Multiplex immunohistochemistry (IHC) was conducted in four representative pair samples. Results Fourteen out of 23 WTS samples (60.8%) showed increased immune scores after CCRT, as calculated by ESTIMATE. The rate of progression-free survival was higher in patients with increased immune scores compared with the remaining patients (83.1% vs. 57.1%, p = 0.25). Tumor mutation burden and neoantigen load were significantly reduced after CCRT (p

Summary: Exome and transcriptome analyses of clinically homogeneous early-stage never-smoker female patients with lung adenocarcinoma were performed to understand tumor-T cell interactions and immune escape points. Using our novel gene panels of eight functional categories in the cancer-immunity cycle, three distinct subgroups were identified in this immune checkpoint blockade-refractory cohort by defective gene expression in two major domains, i.e., type I interferon production/signaling pathway and antigen-presenting machinery. Our approach could play a critical role in understanding immune evasion mechanisms, developing a method for effective selection of rare immune checkpoint blockade responders, and finding new treatment strategies.

BACKGROUND: Prostate cancers exhibit intratumor heterogeneity (ITH), like other cancer types. The ITH may affect diverse phenotypes such as treatment response, drug resistance, and clinical outcomes. It is crucial to consider ITH to understand tumorigenesis. METHODS: Genomic and transcriptomic profiles of prostate cancer patients were investigated to determine which markers are correlated with the degree of tumor heterogeneity. In addition, the correlation between the immune activity and clonality of tumors was examined. RESULTS: Tumor heterogeneity across all prostate cancer samples was variable. However, ITH events were dependent on genomic and clinical features. Interestingly, prostate-specific antigen score increased in tumors with multiple subclones, indicating high-grade tumor heterogeneity. On the other hand, CD8-positive T-cell activation decreased in highly heterogeneous tumors. Intriguingly, PTEN deletion was prominently enriched in high heterogeneity groups, with a strong association with heterozygous loss. Expression of major genes including PTEN, CDC42EP5, RNLS, GP2, NETO2, and AMPD3 was closely related to tumor heterogeneity in association with PTEN deletion. CONCLUSIONS: In prostate cancer, ITH, a potential factor affecting tumor progression, is associated with PTEN deletion and cytotoxic T cell inactivation.

PURPOSE: Relapsed/refractory pediatric cancers show poor prognosis; however, their genomic patterns remain unknown. To investigate the genetic mechanisms of tumor relapse and therapy resistance, we characterized genomic alterations in diagnostic and relapsed lesions in patients with relapsed/refractory pediatric solid tumors using targeted deep sequencing. PATIENTS AND METHODS: A targeted sequencing panel covering the exons of 381 cancer genes was used to characterize 19 paired diagnostic and relapsed samples from patients with relapsed/refractory pediatric solid tumors. RESULTS: The mean coverage for all samples was 930.6× (SD = 213.8). Among the 381 genes, 173 single nucleotide variations (SNVs)/insertion-deletions (InDels), 100 copy number alterations, and 1 structural variation were detected. A total of 72.6% of SNVs in primary tumors were also found in recurrent lesions, and 27.2% of SNVs in recurrent tumors had newly occurred. Among SNVs/InDels detected only in recurrent lesions, 71% had a low variant allele fraction (

BACKGROUND: Signet-ring cell carcinoma (SRCC) is a very rare subtype of colorectal adenocarcinoma (COAD) with a poor clinical prognosis. Although understanding key mechanisms of tumor progression in SRCCs is critical for precise treatment, a comprehensive view of genomic alterations is lacking. MATERIALS AND METHODS: We performed whole-exome sequencing of tumors and matched normal blood as well as RNA sequencing of tumors and matched normal colonic tissues from five patients with SRCC. RESULTS: We identified major somatic alterations and characterized transcriptional changes at the gene and pathway level. Based on high-throughput sequencing, the pattern of mutations and copy number variations was overall similar to that of COAD. Transcriptome analysis revealed that major transcription factors, such as SRF, HNF4A, ZEB1, and RUNX1, with potential regulatory roles in key pathways, including focal adhesion, the PI3K-Akt signaling pathway, and the MAPK signaling pathway, may play a role in the tumorigenesis of SRCC. Furthermore, significantly upregulated genes in SRCCs were enriched for epithelial-mesenchymal transition genes, and accumulation of mucin in intracytoplasm was associated with the overexpression of MUC2. CONCLUSION: The results indicate that the molecular basis of colorectal SRCC exhibits key differences from that of consensus COAD. Our findings clarify important genetic features of particular abnormalities in SRCCs.

High-throughput sequencing is used to identify somatic variants in cancer patients. Here, the authors perform panel-based profiling of 5095 clinical samples and demonstrate that many clinically-actionable variants have low variant allele fractions, requiring assays with high detection sensitivity.

This study investigated changes in the intestinal microbiota during 8-week infliximab maintenance therapy in inflammatory bowel disease (IBD) patients in clinical remission. Microbial compositional differences were analyzed according to the trough level of infliximab (TLI) and mucosal healing (MH) status. 16S rRNA gene-based microbiome profiling was performed on 10 and 74 fecal samples from 10 healthy volunteers and 40 adult IBD patients, respectively. Fecal sampling occurred at 1–2 weeks (1W) and 7–8 weeks (7W) after infliximab infusion. TLI was measured by ELISA at 8 weeks, immediately before the subsequent infusion; MH was evaluated by endoscopy within 3 months. There were no significant changes in microbial composition, species richness, or diversity indices between 1W and 7W. However, 7W samples from the patients with TLI ≥ 5 μg/mL showed an increased species richness compared with patients with TLI < 5 μg/mL, and patients with MH showed increased diversity compared with non-MH patients. Beta-diversity analysis showed clustering between samples in the MH and non-MH groups. LEfSe analysis identified differential composition of Faecalibacterium prausnitzii group according to TLI and MH. In conclusion, these results suggest the potential of fecal microbiota as a response indicator.

Intratumoral heterogeneity (ITH) refers to the presence of distinct tumor cell populations. It provides vital information for the clinical prognosis, drug responsiveness, and personalized treatment of cancer patients. As genomic ITH in various cancers affects the expression patterns of genes, the expression profile could be utilized for determining ITH level. Herein, we present a novel approach to directly detect high ITH defined as a larger number of subclones from the gene expression pattern through machine learning approaches. We examined associations between gene expression profile and ITH of 12 cancer types from The Cancer Genome Atlas (TCGA) database. Using stomach adenocarcinoma (STAD) showing high association, we evaluated the performance of our method in predicting ITH by employing three machine learning algorithms using gene expression profile data. We classified tumors into high and low heterogeneity groups using the learning model through the selection of LASSO feature. The result showed that support vector machines (SVMs) outperformed other algorithms (AUC = 0.84 in SVMs and 0.82 in Naïve Bayes) and we were able to improve predictive power by using both combined data from mutation and expression. Furthermore, we evaluated the prediction ability of each model using simulation data generated by mixing cell lines of the Cancer Cell Line Encyclopedia (CCLE), and obtained consistent results with using real dataset. Our approach could be utilized for discriminating tumors with heterogeneous cell populations to characterize ITH.

A single tumor biopsy specimen is typically used in cancer genome studies. However, it may represent incompletely the underlying mutational and transcriptional profiles of tumor biology. Multi-regional biopsies have the advantage of increased sensitivity for genomic profiling, but they are not cost-effective. The concept of an alternative method such as the pooling of multiple biopsies is a challenge. In order to determine if the pooling of distinct regions is representative at the genomic and transcriptome level, we performed sequencing of four regional samples and pooled samples for four cancer types including colon, stomach, kidney and liver cancer. Subsequently, a comparative analysis was conducted to explore differences in mutations and gene expression profiles between multiple regional biopsies and pooled biopsy for each tumor. Our analysis revealed a marginal level of regional difference in detected variants, but in those with low allele frequency, considerable discrepancies were observed. In conclusion, sequencing pooled samples has the benefit of detecting many variants with moderate allele frequency that occur in partial regions, but it is not applicable for detecting low-frequency mutations that require deep sequencing.