Tumor-initiating Events Research Articles

The role of glycolysis in tumorigenesis: From biological aspects to therapeutic opportunities

Glycolytic metabolism generates energy and intermediates for biomass production. Tumor-associated glycolysis is upregulated compared to normal tissues in response to tumor cell-autonomous or non-autonomous stimuli. The consequences of this upregulation are twofold. First, the metabolic effects of glycolysis become predominant over those mediated by oxidative metabolism. Second, overexpressed components of the glycolytic pathway (i.e. enzymes or metabolites) acquire new functions unrelated to their metabolic effects and which are referred to as “moonlighting” functions. These functions include induction of mutations and other tumor-initiating events, effects on cancer stem cells, induction of increased expression and/or activity of oncoproteins, epigenetic and transcriptional modifications, bypassing of senescence and induction of proliferation, promotion of DNA damage repair and prevention of DNA damage, antiapoptotic effects, inhibition of drug influx or increase of drug efflux. Upregulated metabolic functions and acquisition of new, non-metabolic functions lead to biological effects that support tumorigenesis: promotion of tumor initiation, stimulation of tumor cell proliferation and primary tumor growth, induction of epithelial-mesenchymal transition, autophagy and metastasis, immunosuppressive effects, induction of drug resistance and effects on tumor accessory cells. These effects have negative consequences on the prognosis of tumor patients. On these grounds, it does not come to surprise that tumor-associated glycolysis has become a target of interest in antitumor drug discovery. So far, however, clinical results with glycolysis inhibitors have fallen short of expectations. In this review we propose approaches that may allow to bypass some of the difficulties that have been encountered so far with the therapeutic use of glycolysis inhibitors.

Nucleolin lactylation contributes to intrahepatic cholangiocarcinoma pathogenesis via RNA splicing regulation of MADD

Intrahepatic cholangiocarcinoma (iCCA) is a fatal malignancy of the biliary system. The lack of a detailed understanding of oncogenic signaling or global gene expression alterations has impeded clinical iCCA diagnosis and therapy. The role of protein lactylation, a newly unraveled post-translational modification that orchestrates gene expression, remains largely elusive in the pathogenesis of iCCA. Proteomics analysis of clinical iCCA specimens and adjacent tissues was performed to screen for proteins aberrantly lactylated in iCCA. Mass spectrometry, macromolecule interaction and cell behavioral studies were employed to identify the specific lactylation sites on the candidate protein(s) and to decipher the downstream mechanisms responsible for iCCA development, which were subsequently validated using a xenograft tumor model and clinical samples. Nucleolin (NCL), the most abundant RNA-binding protein in the nucleolus, was identified as a functional lactylation target that correlates with iCCA occurrence and progression. NCL was lactylated predominantly at lysine 477 by the acyltransferase P300 in response to a hyperactivity of glycolysis, and promoted the proliferation and invasion of iCCA cells. Mechanistically, lactylated NCL bound to the primary transcript of MAP kinase-activating death domain protein (MADD) and led to efficient translation of MADD by circumventing alternative splicing that generates a premature termination codon. NCL lactylation, MADD translation and subsequent ERK activation promoted xenograft tumor growth and were associated with overall survival in patients with iCCA. NCL is lactylated to upregulate MADD through an RNA splicing-dependent mechanism, which potentiates iCCA pathogenesis via the MAPK pathway. Our findings reveal a novel link between metabolic reprogramming and canonical tumor-initiating events, and uncover biomarkers that can potentially be used for prognostic evaluation or targeted treatment of iCCA. Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive liver malignancy with largely uncharacterized pathogenetic mechanisms. Herein, we demonstrated that glycolysis promotes P300-catalyzed lactylation of nucleolin, which upregulates MAP kinase-activating death domain protein (MADD) through precise mRNA splicing and activates ERK signaling to drive iCCA development. These findings unravel a novel link between metabolic rewiring and canonical oncogenic pathways, and reveal new biomarkers for prognostic assessment and targeting of clinical iCCA.

Abstract 143: Molecular profiling of tumor-initiation events in rhabdomyosarcoma uncovers mitochondrial vulnerabilities

Abstract Background: Alveolar Rhabdomyosarcoma (ARMS) is a very aggressive soft tissue tumor affecting children and adolescents. It is found that pediatric patients with RMS harboring chimeric PAX fusion transcription factors (TFs) exhibit a greater incidence of tumor relapse, metastasis, and poor survival outcome, thereby underscoring the urgent need to develop effective therapies to treat this subtype of childhood cancer. Methods: We generated a novel ARMS model by stable transduction of myogenic progenitor cells with a cassette encoding the exact PAX3/7-FOXO1 fusion protein found in ARMS tumors. We analyzed genome-wide expression levels with RNA-seq and utilized Cut&Run to map the binding sites of PAX3/7-FOXO1, active histone marks, enhancers, and super-enhancers in our novel model. Hi-C and promoter capture HiC (pCHiC) were also performed to generate 3D chromatin conformation maps in cells expressing the oncogenic TFs. We compared these data with analogous datasets from orthotopic patient-derived xenografts (O-PDXs) of PAX3/7-FOXO1 fusion-positive ARMS tumors from St. Jude and established ARMS cell lines to validate whether our model system recapitulates ARMS tumors. CRISPRi was performed to silence key targets in two representative ARMS cell lines and proliferation was scored after silencing. Next, we found that ARMS tumors displayed anomalies in mitochondrial mass and numbers, metabolic parameters, and membrane potential by performing TEM, Seahorse assays, and FACS-based TMRM and mitotracker Red dye uptake in a panel of ARMS cells and PDX samples. We performed cell viability and colony forming assays in ARMS cells treated with single drugs and combinations of drugs targeting FGFR4 and mitochondrial metabolism. Results: Our data provide evidence to support muscle progenitors as potential cells-of-origin for ARMS. We showed that rewiring of chromatin architecture mediated by PAX3/7-FOXO1 TFs is evident across established cell lines, primary tumors as well as O-PDXs. By integrating PAX3/7-FOXO1 binding, RNA-seq, and pCHiC data, we identified key promoter-enhancer (P-En) interactions that are erased or established de novo at multiple loci of master TFs like MYOD, MYOG and MYCN. We also identified key regulators of proliferation, including FGFR4, and mitochondrial function that are essential for tumor growth and invasiveness. Our data indicated aberrant and enhanced mitochondrial metabolism in ARMS as well as selective sensitivity to mitochondrial inhibitors in RMS cells. Administration of these inhibitors preferentially inhibited cell viability and clonogenicity in ARMS, and prompted a pre-clinical phase II study to test these inhibitors at St. Jude Research Hospital. Conclusion: We present a novel treatment strategy leveraging the mitochondrial dependencies of fusion positive PAX-driven tumors which can be exploited for precision therapy in high-risk ARMS. Citation Format: Bhargab Kalita, Gerard Martinez-Cebrian, Justina McEvoy, Brittney Gordon, Kaley Blankenship, Asa Karlstorm, Elizabeth Stewart, Michael Dyer, Brian Dynlacht. Molecular profiling of tumor-initiation events in rhabdomyosarcoma uncovers mitochondrial vulnerabilities [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 143.

The prognostic effect of immune cell infiltration depends on molecular subtype in Endometrioid Ovarian Carcinomas.

Endometrioid ovarian carcinoma (ENOC) is the second most-common type of ovarian carcinoma, comprising 10-20% of cases. Recently, the study of ENOC has benefitted from comparisons to endometrial carcinomas (EC) including defining ENOC with four prognostic molecular subtypes. Each subtype suggests differential mechanisms of progression, though tumor initiating events remain elusive. There is evidence that the ovarian microenvironment may be critical to early lesion establishment and progression. However, while immune infiltrates have been well studied in high-grade serous ovarian carcinoma, studies in ENOC are limited. We report on 210 ENOC, with clinical follow-up and molecular subtype annotation. Using multiplex immunohistochemistry and immunofluorescence, we examine the prevalence of T cell lineage, B cell lineage, macrophages, and populations with PD-1 or PD-L1 across subtypes of ENOC. Immune cell infiltrates in tumor epithelium and stroma showed higher densities in ENOC subtypes with known high mutation burden (POLEmut and MMRd). While molecular subtypes were prognostically significant, immune infiltrates were not (OS p>0.2). Analysis by molecular subtype revealed that immune cell density was prognostically significant in only the no specific molecular subtype (NSMP) subtype, where immune infiltrates lacking B cells (TILB minus) had inferior outcome (DSS HR:4.0 CI 1.1-14.7, p<0.05). Similar to EC, molecular subtype stratification was generally superior to immune response in predicting outcomes. Subtype stratification is critical for better understanding of ENOC, in particular the distribution and prognostic significance of immune cell infiltrates. The role of B cells in the immune response within NSMP tumors warrants further study.

Tyrosine kinase SRC-induced YAP1-KLF5 module regulates cancer stemness and metastasis in triple-negative breast cancer

SRC is the first identified oncogene, and its aberrant activation has been implicated as a driving event in tumor initiation and progression. However, its role in cancer stemness regulation and the underlying regulatory mechanism are still elusive. Here, we identified a YAP1 tyrosine phosphorylation-dependent YAP1-KLF5 oncogenic module, as the key downstream mediator of SRC kinase regulating cancer stemness and metastasis in triple-negative breast cancer (TNBC). SRC was overexpressed in TNBC patient tissues and its expression level was highly correlated with the tumor malignancy. SRC activation induced, while inhibition of SRC kinase reduced the cancer stemness, tumor cell growth and metastasis in vitro and in vivo. Transcriptomic and proteomic analysis revealed that SRC-mediated YAP1 tyrosine phosphorylation induced its interaction with Kruppel-like factor 5 (KLF5) to form a YAP1/TEAD-KLF5 complex in TNBC cells. YAP1-KLF5 association further promoted TEAD-mediated transcriptional program independently of canonical Hippo kinases, which eventually gave rise to the enhanced cancer stemness and metastasis. Disruption of YAP1-KLF5 module in TNBC cells dramatically attenuated the SRC-induced cancer stemness and metastasis in vitro and in vivo. Accordingly, co-upregulations of SRC and YAP1-KLF5 module in TNBC tissues were significantly positively correlated with the tumor malignance. Altogether, our work presents a novel tyrosine phosphorylation-dependent YAP1-KLF5 oncogenic module governing SRC-induced cancer stemness and metastasis in TNBC. Therefore, targeting YAP1/KLF5-mediated transcription may provide a promising strategy for TNBC treatment with SRC aberrantly activation.

Abstract B006: PBRM1-deficient PBAF complexes target de novo genomic loci to activate NF-κB pathway in kidney cancer

Abstract Polybromo-1 (PBRM1) is the second most commonly mutated gene in kidney cancer after VHL, occurring at a frequency of 30-40%. PBRM1 loss represents a tumor-initiating event and the combined loss of VHL and PBRM1 is necessary and sufficient for renal malignancy. Functionally, PBRM1 is the defining subunit of the polybromo BRG1-associated factor (PBAF) subclass of SWItch/Sucrose Non-Fermentable (SWI/SNF) remodeling complex which regulates chromatin accessibility by sliding, depositing or evicting nucleosomes. Determining context-specific chromatin remodeling by PBRM1 is paramount to understanding how PBRM1 deficiency drives kidney tumorigenesis. We compared the association of SWI/SNF subunits in the presence or absence of PBRM1 and found that PBRM1 loss resulted in a PBAF complex that has undergone alterations in its configuration and targeting specificity: First, the histone binding lobe disengages from the central ATPase subunit. Second, the PBRM1-deficient complexes, despite retaining the DNA binding lobe, occupy aberrant sites, redistributing from promoter proxy regions to distal enhancer regions. The aberrant sites mapped to regions enriched for NF-κB motifs. Indeed, PBRM1-deficient tumors show enhanced NF-κB activity across isogenic tumor models, genetically modified mouse models and clinical samples. We believe that the PBRM1-deficient PBAF complexes enhance the recruitment of nuclear factor RELA, a subunit of the NF-κB complex - this recruitment requires the ATPase function of the SWI/SNF complexes since BRG1/BRM ATPase inhibitor dampens the expression of NF-κB target genes and RELA chromatin occupancy. Proteasome inhibitor bortezomib reverses NF-κB activity by reducing RELA binding at regions bound by PBRM1-deficient PBAF and delays PBRM1-deficient tumor growth. In conclusion, the PBRM1 tumor suppressor safeguards the chromatin by repressing aberrant liberation of pro-tumorigenic NF-κB target genes by residual PBRM1-deficient PBAF complexes. Inhibition of NF-κB activity by bortezomib could be a therapeutic strategy for PBRM1-deficient kidney cancer. Citation Format: Xiaosai Yao, Jing Han Hong, Amrita Nargund, Bin Tean Teh. PBRM1-deficient PBAF complexes target de novo genomic loci to activate NF-κB pathway in kidney cancer. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr B006.

Modulation of biomarkers associated with risk of cancer in humans by olive oil intake: A systematic review

This systematic review summarized the role of olive oil intake in modulation of cancer risk biomarkers in healthy adults. A total of four randomized clinical trials with crossover design were included with intervention periods ranging from three to eight weeks, none of them at high risk of bias. meta-analysis was not performed because the studies were heterogeneous. Results showed that continuous olive oil intake was associated with the reduction of oxidized DNA bases, IL-8, TNF-α, and 8-OH deoxyguanosine, but did not affect ethene-DNA adducts. In summary, this study showed a potential role of olive oil intake by healthy individuals for prevention and repair of cancer-related DNA damage, through lower levels of markers of oxidative DNA damage and inflammation. High levels of these molecules are present and linked with tumor initiation and other carcinogenesis-related events. Therefore, olive oil is a promising agent for cancer risk reduction. To make this association robust, more intervention studies are needed, especially high-quality randomized controlled trials evaluating similar biomarkers over longer periods of time.

Genome maintenance in retinoblastoma: Implications for therapeutic vulnerabilities.

Retinoblastoma (RB) is a pediatric ocular malignancy that is initiated mostly by biallelic inactivation of the RB transcriptional corepressor 1 (RB1) tumor suppressor gene in the developing retina. Unlike the prevailing prediction based on multiple studies involving RB1 gene disruption in experimental models, human RB tumors have been demonstrated to possess a relatively stable genome, characterized by a low mutation rate and a few recurrent chromosomal alterations related to somatic copy number changes. This suggests that RB may harbor heightened genome maintenance mechanisms to counteract or compensate for the risk of massive genome instability, which can potentially be driven by the early RB1 loss as a tumor-initiating event. Although the genome maintenance mechanisms might have been evolved to promote RB cell survival by preventing lethal genomic defects, emerging evidence suggests that the dependency of RB cells on these mechanisms also exposes their unique vulnerability to chemotherapy, particularly when the genome maintenance machineries are tumor cell-specific. This review summarizes the genome maintenance mechanisms identified in RB, including findings on the roles of chromatin regulators in DNA damage response/repair and protein factors involved in maintaining chromosome stability and promoting survival in RB. In addition, advantages and challenges for exploiting these therapeutic vulnerabilities in RB are discussed.

Tracking the Evolution of Metastasis with Self-Functionalized 3D Nanoprobes.

Despite recent advances in cancer treatment, metastasis is the cause of mortality in 90% of cancer cases. It has now been well-established that dissemination of cancer cells to distant sites occurs very early during tumorigenesis, resulting in the minimal effect of surgical or chemotherapeutic treatments after the detection of metastasis. The underlying reason for this challenge is mostly due to the limited understanding of molecular mechanisms of the metastasis cascade, particularly related to metastatic traits. Therefore, there is an urgent need to investigate this currently invisible evolution of metastasis. The tracking of metastasis evolution has not been addressed yet. Here, we introduce, for the first time, a synchronous approach to unveil the molecular mechanisms of the metastasis cascade. As cancer stem cells (CSCs) demonstrate cancer initiation, drug resistance, metastasis, and tumor relapse and can exist in a quasi-intermediate epithelial-mesenchymal transition state, the tumor-initiating events during a CSCs metamorphosis were monitored with single-cell sensitivity. Because of the invasive and resistive properties of the metastable intermediate CSCs, investigation of the molecular profiles of the quasi-intermediate CSCs was necessary for the detection of metastasis dissemination. For this purpose, the ultrasensitive technique of surface-enhanced Raman scattering (SERS) was adopted. Titanium-based, biocompatible three-dimensional (3D) nanoprobes that were synthesized for multiphoton ionization achieved a substantial SERS enhancement of ∼80-fold due to the oxygen vacancy-enriched composition of the nanoprobes. The 3D interconnected complex nanoarchitecture of the nanoprobes enabled us to entrap the nonadherent CSCs of three metastatic cancer cell lines (triple negative breast adenocarcinoma (MDAMB231), human Caucasian colon adenocarcinoma (COLO 205), and cervical adenocarcinoma (HeLa)─all very aggressive forms of cancer). The nanoprobes not only promoted the CSC proliferation to successfully attain the quasi-intermediate states but also monitored its reprogramming into a cancer cell state. The nanoprobes substantially amplified weak intracellular Raman signals to capture the molecular events during a CSC transformation. The detection of cancer was achieved with 100% accuracy. We experimentally demonstrated that the molecular signatures of CSC reprogramming are cancer-type specific. This observation enabled us to identify the origin of metastasis with 100% accuracy, providing more clarity on the relatively unknown quasi-intermediate states. This first demonstration of CSC-based tracking of metastasis evolution has the potential to provide an insightful perspective of tumorigenesis that could be useful in cancer diagnosis and prognosis as well as in the monitoring of therapeutic interventions.

Endotoxin Triggers Tumor Initiation Events in Nontumorigenic Breast Epithelial Cells and Enhances Invasion-Related Phenotype in Pretumorigenic and Tumorigenic Breast Epithelial Cells.

Inflammation is associated with the development of several cancers, including breast cancer. However, the molecular mechanisms driving breast cancer initiation or enhancement by inflammation are yet to be deciphered. Hence, we opted to investigate the role of inflammation in initiating and enhancing tumor-like phenotypes in nontumorigenic, pretumorigenic, and tumorigenic breast epithelial cells. Noncytotoxic endotoxin (ET) concentrations capable of inducing an inflammatory phenotype were determined for the different cell lines. Results showed that short-term ET exposure upregulated matrix metalloproteinase-9 (MMP-9) activity in nontumorigenic mammary epithelial cells of mouse (SCp2) and human origins (HMT-3522 S1; S1) and upregulated inflammatory mediators including nitric oxide (NO) and interleukin 1-β in tumorigenic human breast cells (MDA-MB-231), all in a dose-dependent manner. Long-term ET treatment, but not short-term, triggered the migration of SCp2 cells, and proliferation and migration of tumorigenic human breast cells MCF-7 and MDA-MB-231. Both short- and long-term ET exposures preferentially enhanced the invasion of pretumorigenic S1-connexin 43 knockout (Cx43-KO S1) cells compared to their nontumorigenic S1 counterparts. Moreover, both ET exposures disrupted lumen formation and apicolateral distribution of β-catenin in 3D cultures of S1 cells. In conclusion, ET treatment at concentrations that elicited inflammatory phenotype triggered tumor initiation events in nontumorigenic and pretumorigenic breast cells, and increased tumorigenicity of breast cancer cells. Our findings highlight the role of inflammation in enhancing migration, invasion, and loss of normal 3D morphology and suggest that such inflammatory insults can “add injury” to pretumorigenic and tumorigenic breast epithelial cells.

The Merkel Cell Polyomavirus T Antigens Function as Tumor Promoters in Murine Skin.

Simple SummaryMerkel cell polyomavirus, a recently discovered human virus, is linked to the development of a rare form of skin cancer called Merkel cell carcinoma. The virus does not replicate in cancer cells, yet there is continued expression of viral proteins known as T antigens. The T antigens are believed to contribute to Merkel cell carcinoma development, yet how they do so remains an active area of research. In this study, we used transgenic mice expressing the viral T antigens in their skin to determine at which stage of skin cancer development these viral proteins function. We discovered that the Merkel cell polyomavirus T antigens function as tumor promoters, rather than tumor initiators, in the skin. These findings suggest that other tumor-initiating events may cooperate with the tumor-promoting activities of the viral T antigens, thus providing important insight into how Merkel cell polyomavirus can cause cancer in human skin.Merkel cell polyomavirus (MCPyV) causes the majority of human Merkel cell carcinomas (MCC), a rare but highly aggressive form of skin cancer. We recently reported that constitutive expression of MCC tumor-derived MCPyV tumor (T) antigens in the skin of transgenic mice leads to hyperplasia, increased proliferation, and spontaneous epithelial tumor development. We sought to evaluate how the MCPyV T antigens contribute to tumor formation in vivo using a classical, multi-stage model for squamous cell carcinoma development. In this model, two chemical carcinogens, DMBA and TPA, contribute to two distinct phases of carcinogenesis—initiation and promotion, respectively—that are required for tumors to develop. By treating the MCPyV transgenic mice with each chemical carcinogen, we determined how the viral oncogenes contributed to carcinogenesis. We observed that the MCPyV T antigens synergized with the tumor initiator DMBA, but not with the tumor promoter TPA, cause tumors. Therefore, the MCPyV tumor antigens function primarily as tumor promoters, similar to that seen with human papillomavirus (HPV) oncoproteins. These studies provide insight into the role of MCPyV T antigen expression in tumor formation in vivo and contribute to our understanding of how MCPyV may function as a human DNA tumor virus.

ZEB1 enhances Warburg effect to facilitate tumorigenesis and metastasis of HCC by transcriptionally activating PFKM.

Metabolic reprogramming, especially Warburg effect, is a key event in tumor initiation and progression. ZEB1 plays a vital role in metastasis of various cancers. We previously found that ZEB1 was excessively expressed in hepatocellular carcinoma (HCC) and its high expression was closely correlated with metastasis and recurrence of HCC. We want to know whether glycolytic enzymes are regulated by ZEB1 and contribute to carcinogenesis and metastasis of HCC.Methods: To explore whether ZEB1 could enhance glycolysis in HCC, we knocked down ZEB1 by short hairpin RNA (shRNA) in MHCC-97H and HCC-LM3 cells and performed glucose uptake, lactate production, ECAR and OCR assays. To investigate how ZEB1 enhances glycolysis, the protein levels of glycolytic enzymes were detected in the same cell lines using Western blot. The regulatory effect of ZEB1 on PFKM mRNA level was confirmed by RT-qPCR, luciferase report assay and ChIP assay. In order to assess the role of ZEB1-PFKM axis in cell proliferation, cell counting and CCK-8 assays were performed in MHCC-97H and HCC-LM3 cell lines knocked down for ZEB1 and further re-expressed for either ZEB1 or PFKM or not. To explored whether the ZEB1-PFKM axis also functions in HCC cell migration, invasion and metastasis, the same MHCC-97H and HCC-LM3 cell lines were performed for wound healing assays, transwell assays and colony formation assays, meanwhile, MHCC-97H cell lines were performed for orthotopic liver transplantation assays. Finally, the expression of ZEB1 and PFKM were examined in human liver cancer specimens and non-tumorous liver tissues using immunohistochemical and Western blot.Results: We found that ZEB1 transcriptionally upregulates the expression of the muscle isoform of phosphofructokinase-1 (PFKM), a rate-limiting enzyme in glycolysis. Intriguingly, a non-classic ZEB1-binding sequence in the promoter region of PFKM was identified through which ZEB1 directly activates the transcription of PFKM. Silencing of ZEB1 in MHCC-97H and HCC-LM3 cell leads to impaired PFKM expression, glycolysis, proliferation and invasion, and such impairments are rescued by exogenous expression of PFKM. Importantly, in-situ HCC xenograft assays and studies from TCGA database demonstrate that ZEB1-PFKM axis is crucial for carcinogenesis and metastasis of HCC.Conclusions: Our study reveals a novel mechanism of ZEB1 in promoting HCC by activating the transcription of PFKM, establishing the direct link of ZEB1 to the promotion of glycolysis and Warburg effect and suggesting that inhibition of ZEB1 transcriptional activity toward PFKM may be a potential therapeutic strategy for HCC.

MP08-08 GENOMIC LANDSCAPE AND MOLECULAR CHARACTERIZATION OF RENAL CELL CARCINOMA IN DIALYSIS PATIENTS

You have accessJournal of UrologyKidney Cancer: Basic Research & Pathophysiology I (MP08)1 Apr 2020MP08-08 GENOMIC LANDSCAPE AND MOLECULAR CHARACTERIZATION OF RENAL CELL CARCINOMA IN DIALYSIS PATIENTS Ryohei Takahashi*, Nobuyuki Tanaka, Fuyuki Miya, Takashi Kamatani, Toshikazu Takeda, Kazuhiro Matsumoto, Shinya Morita, Takeo Kosaka, Ryuichi Mizuno, Shuji Mikami, Kazuhiro Kakimi, Tatsuhiko Tsunoda, and Mototsugu Oya Ryohei Takahashi*Ryohei Takahashi* More articles by this author , Nobuyuki TanakaNobuyuki Tanaka More articles by this author , Fuyuki MiyaFuyuki Miya More articles by this author , Takashi KamataniTakashi Kamatani More articles by this author , Toshikazu TakedaToshikazu Takeda More articles by this author , Kazuhiro MatsumotoKazuhiro Matsumoto More articles by this author , Shinya MoritaShinya Morita More articles by this author , Takeo KosakaTakeo Kosaka More articles by this author , Ryuichi MizunoRyuichi Mizuno More articles by this author , Shuji MikamiShuji Mikami More articles by this author , Kazuhiro KakimiKazuhiro Kakimi More articles by this author , Tatsuhiko TsunodaTatsuhiko Tsunoda More articles by this author , and Mototsugu OyaMototsugu Oya More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000828.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The number of chronic renal failure has been rapidly growing. Further, not only in advanced nations, the number of dialysis patients continues to increase explosively even though in a developing nation. It’s evident that long-term dialysis induces the onset of renal cell carcinomas (RCCs). Marked differences in the genetic and epigenetic backgrounds of cancer cells have been revealed by advances in genome sequencing in various cancer types, yet little is known about those landscapes of RCC in dialysis patients. Herein, we show an integrated genomic and molecular study using to 40 dialysis patient RCC specimens, clarifying the tumor biology and identifying potential therapeutic targets for RCCs under dialysis. METHODS: In total, we conducted whole-exome sequencing (n=20) with paired normal DNA, RNA sequencing (n=14), comprehensive DNA methylation microarray (n=25), or immunohistochemistry (n=35). Notably, assessing recent immune-checkpoint targets e.g., CD3, CD8, CD20, CTLA4, FOXP3, PD-1, and PD-L1 expression, we histologically characterized the tumor immune microenvironment in dialysis patient RCCs. RESULTS: Whole-exome sequencing detected 55.5 somatic mutations per tumor, and ninety-four mutated genes were overlapped in multiple cases. The VHL somatic mutations were found in 58% of clear cell RCCs (ccRCCs) occurred in dialysis patients. Rather, no apparent difference was found comparing to the COSMIC database. Further, PBRM1 and SETD2 somatic mutations were found in 17% and 8% of dialysis patient ccRCC, respectively. Conversely, no VHL somatic mutation was not found in RCC related to acquired cystic disease of the kidney (n=6). CONCLUSIONS: Inactivation of VHL gene is an archetypical tumor-initiating event in ccRCC. Also, our subset of ccRCC occurred in dialysis patients was favored by VHL somatic mutations in tumorgenesis, suggesting that oncogenic mechanisms of ccRCC may be similar under dialysis. However, RCC in dialysis patients must be a global concern, thus further study should be warranted. Source of Funding: none © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e108-e109 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ryohei Takahashi* More articles by this author Nobuyuki Tanaka More articles by this author Fuyuki Miya More articles by this author Takashi Kamatani More articles by this author Toshikazu Takeda More articles by this author Kazuhiro Matsumoto More articles by this author Shinya Morita More articles by this author Takeo Kosaka More articles by this author Ryuichi Mizuno More articles by this author Shuji Mikami More articles by this author Kazuhiro Kakimi More articles by this author Tatsuhiko Tsunoda More articles by this author Mototsugu Oya More articles by this author Expand All Advertisement PDF downloadLoading ...

Retrotransposon insertions can initiate colorectal cancer and are associated with poor survival

Genomic instability pathways in colorectal cancer (CRC) have been extensively studied, but the role of retrotransposition in colorectal carcinogenesis remains poorly understood. Although retrotransposons are usually repressed, they become active in several human cancers, in particular those of the gastrointestinal tract. Here we characterize retrotransposon insertions in 202 colorectal tumor whole genomes and investigate their associations with molecular and clinical characteristics. We find highly variable retrotransposon activity among tumors and identify recurrent insertions in 15 known cancer genes. In approximately 1% of the cases we identify insertions in APC, likely to be tumor-initiating events. Insertions are positively associated with the CpG island methylator phenotype and the genomic fraction of allelic imbalance. Clinically, high number of insertions is independently associated with poor disease-specific survival.

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature

ATDC is required for the initiation of KRAS-induced pancreatic tumorigenesis.

Pancreatic adenocarcinoma (PDA) is an aggressive disease driven by oncogenic KRAS and characterized by late diagnosis and therapeutic resistance. Here we show that deletion of the ataxia-telangiectasia group D-complementing (Atdc) gene, whose human homolog is up-regulated in the majority of pancreatic adenocarcinoma, completely prevents PDA development in the context of oncogenic KRAS. ATDC is required for KRAS-driven acinar-ductal metaplasia (ADM) and its progression to pancreatic intraepithelial neoplasia (PanIN). As a result, mice lacking ATDC are protected from developing PDA. Mechanistically, we show ATDC promotes ADM progression to PanIN through activation of β-catenin signaling and subsequent SOX9 up-regulation. These results provide new insight into PDA initiation and reveal ATDC as a potential target for preventing early tumor-initiating events.

Analysis of M1 and M2 tumor associated macrophages in tongue squamous cell carcinomas.

Analysis of M1 and M2 tumor associated macrophages in tongue squamous cell carcinomas.

Sulforaphane Inhibits the Acquisition of Tobacco Smoke-Induced Lung Cancer Stem Cell-Like Properties via the IL-6/ΔNp63α/Notch Axis.

Background: Tobacco smoke (TS) critically contributes to the development of lung cancer; however, the underlying molecular mechanisms remain unclear. The induction of cancer stem cells (CSCs) by TS represents an early event in tumor initiation. The lung cancer-related gene ΔNp63α is highly expressed in epithelial tissues and drives tumor formation and cancer stem cell properties. This study investigated the role of ΔNp63α in the long-term acquisition of TS-induced lung CSC-like properties.Methods: The expression levels of ΔNp63α, lung CSC markers, and interleukin (IL)-6 in lung carcinoma specimens were determined by western blotting and enzyme linked immunosorbent assays. Human bronchial epithelial (HBE) cells were chronically exposed to 2 % cigarette smoke extract for 55 passages, following which colony formation capacity, expression of proteins associated with malignant transformation, lung CSC markers, and tumor incidence were investigated. The effects of ΔNp63α on long-term TS exposure-induced lung CSC-like properties and Notch activation were analyzed using tumorsphere formation ability, immunofluorescence assays, luciferase reporter assays, and western blotting. The roles of IL-6 on chronic TS exposure-induced lung CSC-like properties and ΔNp63α expression were also examined. Moreover, the effects of sulforaphane (SFN) on TS-transformed lung CSC-like properties, IL-6 and ΔNp63α expression, and Notch signaling were investigated in vitro and in vivo.Results: Higher levels of ΔNp63α were observed in the lung cancer tissues of smokers than in those of non-smokers, whereas ΔNp63α was positively correlated with CD133 and Oct4 expression in lung cancer tissues. Data from the in vivo and in vitro experiments demonstrated that long-term TS exposure-transformed HBE (THBE) cells acquired lung CSC-like properties. Furthermore, ΔNp63α transcriptionally activated the Notch signaling pathway to promote the acquisition of CSC-like properties by the THBE cells. TS upregulated IL-6, which increased ΔNp63α expression in THBE sphere-forming cells. Finally, SFN inhibited the TS-induced CSC-like properties of THBE cells via the IL-6/ΔNp63α/Notch axis.Conclusion: Our data suggest that the IL-6/ΔNp63α/Notch axis plays an important role in the long-term TS exposure-induced acquisition of lung CSC-like properties and SFN intervention.

MiR-374b reduces cell proliferation and cell invasion of cervical cancer through regulating FOXM1.

Deregulation of microRNAs (miRNAs) has been identified as critical event in tumor initiation and progression. We aimed to explore the role of miR-374b in cervical cancer progression. MiR-374b expression was detected using qRT-PCR in cervical cancer tissues compared with normal counterparts. Cell proliferation and invasion ability were detected using Cell Counting Kit-8 (CCK8) cell proliferation and transwell invasion assay. Dual luciferase reporter assay, qRT-PCR, and Western blot analysis were used to demonstrate that FOXM1 was a target of miR-374b. We demonstrated that downregulation of miR-374b was frequently examined in cervical cancer tissues compared with normal counterparts. Furthermore, we showed the lower miR-374b expression associated with lymph node metastasis and advanced FIGO stage in patients with cervical cancer. Furthermore, ectopic expression of miR-374b could significantly decrease cell proliferation and invasion ability. However, inhibition of miR-374b had opposite effects. Dual luciferase reporter assay, qRT-PCR, and Western blot analysis revealed that miR-374b overexpression suppressed cell proliferation and invasion ability via affecting FOXM1 expression. These results indicated that miR-374b acted as tumor suppressor and may serve as a potential target for cervical cancer treatment.