bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1175: The establishment of single colorectal cancer organoid clones derived from regional biopsies for studying tumor heterogeneity
Authors: Song Myoung-Hyun , Ku Ja-Lok
Published: August 2018

Nowadays, there is a spotlight on organoid culture, which is cultivated in 3D by using specimens derived from human or another mammalian. In addition, in the process of testing and screening anticancer drugs in vitro, the limitations of 2D culture have been pointed out because homogenous culture condition does not sufficiently represent the real environment in human body. Simultaneously, there has been consensus that 3D models such as spheroids and organoids are more physiologically similar to in vivo system when compared to 2D. In fact, tumor tissue grows in 3D and in heterogenous environment including extra-cellular matrix, immune cells and various lineage of cells differentiated from stem cells. To further comprehend complex in vivo tumor development pathway, new experimental model for mimicking real three-dimensional biopsy has been required and successfully become a part of biological field. Accordingly, organoid culture technic as an emerging next generation ex-vivo model has drawn tremendous attention for its advantages in lots of experimental and therapeutic application. Thus, we have established organoid (3D) lines by isolating tumor epithelium from colon cancer patient tissue and to look into the heterogenous environment of human intestine as well as investigating sensitivity in response to various stimulations such as anti-cancer reagents treatment and irradiation (professors Seung-Yong Jeong and Ji-Won Park contributed this work). And in particular, six to eight single organoids were isolated from the primary passage in each regional biopsy. 4 tumor tissues and 6 to 8 single organoids were obtained from a patient and each biopsy, respectively. In sum, more than 30 organoid lines from one patient were established and cultured to confirm both heterogeneity among regional biopsies and single organoids derived from each biopsy. Each single organoid was successfully isolated by using micromanipulator and micropipette without contamination. Then, we confirmed whether single clones were solely isolated. Furthermore, during the process of expansion of each organoid population, we observed differences in morphology and proliferation rate among organoid lines. However, distinct mechanisms that mainly influences on the tumor heterogeneity are still not fully understood. The technic of single organoid clone isolation could give insights for further studies on investigating heterogeneity among regional tumor biopsies.

Citation Format: Myoung-Hyun Song, Ja-Lok Ku. The establishment of single colorectal cancer organoid clones derived from regional biopsies for studying tumor heterogeneity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1175.
Abstract 1179: PAM50 subtype admixture in individual breast cancers and the relationship of this intratumoral heterogeneity to clinical variables
Authors: Gann Peter H. , Kumar Neeraj , Zhao Dan , Sethi Amit
Published: August 2018

Classification of breast cancers by PAM50 gene profiling assigns each cancer to one of five intrinsic subtypes. However, individual cancers vary in their adherence to the assigned prototype, and some may exhibit expression patterns that indicate admixture with other subtypes. The prevalence of this intratumoral heterogeneity phenomenon and the relationship of subtype admixture to clinical endpoints has not been extensively studied. We obtained microarray data on 1,460 cases from the public Gene Expression Omnibus and processed the data to normalize and log-transform expression levels and control for batch effects. For each case, we extracted levels for PAM50 genes and computed the Mahalanobis distance in multidimensional space for each case from all five centroids, including the one assigned. This metric obtains the standardized distance from a centroid for a single case while accounting for correlation between genes. We then discriminated pure from admixed cases by setting criteria for distance from the assigned centroid as well as distance from nonassigned centroids. Using the criteria that pure cases are those within the 75th percentile of distance from the assigned centroid, while being greater than the 75th percentile from any other centroid, we found that 59% of basal cases were categorized as pure, versus luminal A 31%, luminal B 35%, HER2 34% and normal 27%. We used t-Distributed Stochastic Neighbor Embedding (t-SNE) plots to visualize these admixtures in two dimensions. This confirmed that basal cancers were more heterogeneous than the other types, and that LumA, LumB and normal were more frequently admixed than other combinations. Pure LumA cases were less likely to be high-grade than LumA cases admixed with LumB, basal, HER2 or null cases not near any other centroid (18.5% vs. 7.2%, P < 0.01). Pure basal cases were more likely to be high-grade than basal cases admixed with any other subtype. Kaplan-Meier curves for metastasis-free survival for pure LumA were very similar to admixed cases for the first 5 years, but then diverged, with worse survival when LumA was admixed with worse subtypes. These results support the hypothesis that subtype admixture, or at least the tendency for some breast cancers to exhibit this form of intratumoral heterogeneity, can be identified and that it should be explored for clinical consequences, including failure to respond to subtype-specific therapy.

Citation Format: Peter H. Gann, Neeraj Kumar, Dan Zhao, Amit Sethi. PAM50 subtype admixture in individual breast cancers and the relationship of this intratumoral heterogeneity to clinical variables [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1179.
Abstract 1183: Targeted sequencing of cell-free DNA data enables comprehensive profiling of tumor copy number landscape from blood
Authors: Barbacioru Catalin , Collisson Eric , Chudova Darya , Odegaard Justin , Lanman Richard , Talasaz AmirAli
Published: August 2018

Background: The evolution of cancer genomes within a single tumor creates mixed cell populations with divergent somatic mutational architectures. Inference of tumor subpopulations has been disproportionately focused on the assessment of somatic point mutations, whereas computational methods targeting copy number alterations (CNA) in targeted sequencing data remain underdeveloped.

Methods: Using a large database of clinical cell-free DNA (cfDNA) sequencing data (Guardant Health, CA), we developed a coverage-based probabilistic model to simultaneously normalize molecular coverage, segment the genome, predict copy number alterations, and estimate the tumor content in cfDNA samples, while accounting for mixtures of cell populations. This model was technically validated using tissue fluorescence in situ hybridization (FISH) data and then applied to a unique set of cfDNA sequencing data from >5,000 normal and clinical samples spanning multiple cancer types, where model predictions were compared to the observed allelic frequencies of somatic driver mutations and heterozygous germline SNPs.

Results: Technical validation against FISH-derived tissue copy number estimates demonstrated high concordance with model estimates. Analysis of clinical samples demonstrated a wide range of copy number architectures, including prevalent copy number neutral loss-of-heterozygosity, large chromosomal deletions, and high focal amplifications, all of which are not easily detected and/or differentiated with standard sequencing analysis approaches on highly-fragmented cfDNA.

Conclusion: Our results show that probabilistic modeling of coverage data generated from targeted cfDNA sequencing can detect and differentiate heterogeneous tumor populations with diverse somatic variations, CNA, and LOH landscape. This method may enable improvements in CNA detection accuracy, sensitivity, and specificity and provides more precise interrogation of tumor fraction and clonal architecture.

Citation Format: Catalin Barbacioru, Eric Collisson, Darya Chudova, Justin Odegaard, Richard Lanman, AmirAli Talasaz. Targeted sequencing of cell-free DNA data enables comprehensive profiling of tumor copy number landscape from blood [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1183.
Abstract 1186: Intratumoral heterogeneity in small cell carcinoma of the lung: An evolutionary and ecologic process
Authors: Peacock Craig D. , Gopal Priyanka , Petty Aaron , Rogacki Kevin , Abazeed Mohamed E.
Published: August 2018

It is increasingly apparent that tumors represent dynamic structures in which cell populations, defined by genetic, epigenetic and non-genetic variation, compete for space and resources, while attempting to evade host defenses, resist therapeutic interventions and colonize new environments. Yet, the extent of this intratumoral genetic heterogeneity and the rules governing this ecosystem remain largely unknown. Using a large inventory of patient-derived xenograft models and an ex vivo culture system that maintains the transcriptional fidelity of the primary tumors, we have interrogated small cell lung cancer (SCLC) as a tractable model system for studying tumor evolution. In the process, we have identified at least three morphologically distinct intratumoral subpopulations across several samples: (i) suspended aggregates of small cells (neuroendocrine or NE), (ii) larger, pleomorphic cells with visible cytoplasm and spindle-like membrane extensions growing as a monolayer (mesenchymal or MS) and (iii) pre-suspension aggregates that are nested above mesenchymal-like cells (proneural or PN). Moreover, we have shown that these subpopulations are functionally distinct as measured by cellular proliferation, migration/invasion ability and sensitivity to chemotherapy/radiation. Intriguingly, distinct inter-tumoral transcriptional states assembled from earlier analyses of SCLC gene expression values across 53 and 71 cell lines and primary tumors, respectively, were preserved in the three intratumoral subpopulations within our examined SCLC lines. The proportion of each well-defined subpopulation varied across samples, suggesting sample-specific fractional setpoints. Finally, we have identified transcription factors that function as central nodes in the gene expression networks of each population and have used computational tools to nominate and functionally confirm biological processes within each population. Namely, we have shown that ASCL1 marks the rapidly proliferating NE population, NEUROD1 marks the primitive PN population and YAP1 marks the slow-growing MS population. We posit that understanding the SCLC ecosystem will provide substantial insight into its biological and clinical behavior and advance therapeutic possibilities in this recalcitrant disease.

Citation Format: Craig D. Peacock, Priyanka Gopal, Aaron Petty, Kevin Rogacki, Mohamed E. Abazeed. Intratumoral heterogeneity in small cell carcinoma of the lung: An evolutionary and ecologic process [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1186.
Abstract 1204: Incidences of malignant primary soft-tissue sarcomas regardless of primary site: A nationwide population-based study in Taiwan
Authors: Hung Giun-Yi , Horng Jiun-Lin , Yen Chueh-Chuan
Published: August 2018

Population-based studies on soft tissue sarcomas (STS) incidence beyond extremities and trunk wall are lacking in Asia. In this study, we aimed to report the incidences of STS arise in any part of the body. The data of primary STS registered in the population-based Taiwan Cancer Registry during 2007 and 2013 was acquired via the Health and Welfare Data Science Center, Taiwan. Histologic subtype-, age-, and gender-specific STS incidence rates of all sites were analyzed. A total of 11393 subjects were identified, with an age-standardized incidence rate of 5.62 (95% CI, 5.51-5.73) per 100,000 person-years. Approximately 30% of STS occurred in soft tissues (ICD-O-3 topography codes of C47, C49), and 70% occurred in all other primary sites (ICD-O-3 topography codes of C00-C80 except C47, C49, C40 and C41). The three most common primary sites other than soft tissues were stomach (15.9%), skin (14.3%) and small intestine (10.5%). Gastrointestinal stromal tumor (GIST) was the most common subtype, accounting for 29.2% of STS, followed by liposarcoma (11.5%) and leiomyosarcoma (9.7%). For overall STS, no significant incidence trend was identified during 2007-2013. However, a significant declining trend in incidence rate of undifferentiated pleomorphic sarcoma was found (annual percentage change, APC, -7.8%). By contrast, a significant upward trend was identified in other specified sarcomas (APC, 7.3%). For the first time, this analysis demonstrated that STS incidence varied by histologic subtype, gender, age, and primary site in Asians. In the future, more population-based studies should be performed in Asians for comparison with the results from Western countries to better clarification if racial variation exists in any subtype-specific incidence rates of STS.

Citation Format: Giun-Yi Hung, Jiun-Lin Horng, Chueh-Chuan Yen. Incidences of malignant primary soft-tissue sarcomas regardless of primary site: A nationwide population-based study in Taiwan [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1204.
Abstract 1208: Is the decrease in the incidence of large cell carcinoma of the lung due to changes in classification towards adenocarcinoma
Authors: Hashim Dana , Znaor Ariana , Travis William , Boffetta Paolo
Published: August 2018

Background: Data from many populations show a decrease in the incidence of large cell carcinoma (LCC) of the lung while incidence of lung adenocarcinoma (AC) is decreasing to a lower rate or even increasing from the 1990s. We compared the changes in incidence of lung LCC and AC worldwide to test the hypothesis that at least part of the decline in LCC incidence was due to classification of these tumors as AC.

Methods: We analyzed the annual percent change (APC) in the age-standardized rates (ASRs) of lung LCC and AC incidence between 1996 and 2007 in 78 high-quality cancer registries from Europe, Asia, North America, and South America, using linear regression.

Results: Among women, the median APC of LCC incidence was -5.42, and that of AC incidence was -0.96. There was a positive correlation between the two measures (β=0.29; p=0.01). The APC of LCC incidence was negative in 64 populations (82.1%); that of AC incidence was negative in 50 populations (63.3%, p of the χ2 distribution = 0.07). Among women, the median APC for LCC and AC incidence was -5.06 and +2.11, respectively. The correlation between the two measures was 0.17 (p=0.03). The APC of LCC incidence was negative in 59 populations (76.6%); that of AC incidence was negative in 23 populations (29.9%, p of the χ2 distribution = 0.41).

Conclusions: The decrease in LCC may be, in part, due to changes in histologic classification and triaging towards a diagnosis of adenocarcinoma.

Citation Format: Dana Hashim, Ariana Znaor, William Travis, Paolo Boffetta. Is the decrease in the incidence of large cell carcinoma of the lung due to changes in classification towards adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1208.
Abstract 1210: Trend in the incidence of gynecologic malignancies in Federal Teaching Hospital Abakaliki: A 5-year review
Authors: Agboeze Joseph , Onoh Robinson , Igwe Matthew
Published: August 2018

Background: Gynecological malignancies are common and are among the leading causes of cancer-related deaths worldwide Objective: To determine the trend in the incidence of gynaecological malignancies in Federal Teaching Hospital, Abakaliki, Nigeria.

Methods: This was a retrospective study. The study population was the patients diagnosed of gynaecological cancers at the Federal Teaching Hospital, Abakaliki between January, 2012 to December 2015. Data were extracted from case notes of patients, discharge books and the operating theatre record books. The data were analyzed using Epi Info version 7.1.4 and the results expressed in descriptive statistics by simple percentages.

Results: There were 2528 gynaecological admissions during the period. There were 97 women who had genital tract malignancies giving an incidence of 3.8% of gynaecological admissions. Cervical cancer was the most common female genital tract malignancy occurring in 68% of gynaecological cancers, followed by ovarian cancer (11.3%), Endometrial cancer (8.3%), Vulva cancer (6.2%),Choriocarcinoma (4.1%), and the least was leiomyosarcoma (1.0%). The mean age was 54.2 ±11.9 years.The incidences of cervical, ovarian vulva and endometrial cancers showed a steady increase over the period. Choriocarcinoma did not show a significant change in incidence.

Conclusion: This study showed the rising incidences of gynaecological cancers. Cancer of the cervix is the commonest gynaecological malignancy and most patients presented late. Cervical cancer screening programmes, early detection and awareness campaign is highly recommended.

Citation Format: Joseph Agboeze, Robinson Onoh, Matthew Igwe. Trend in the incidence of gynecologic malignancies in Federal Teaching Hospital Abakaliki: A 5-year review [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1210.
Abstract 1212: Urinary bladder cancer in Sokoto, Northwestern Nigeria: A 10-year histopathological review
Authors: Sahabi Saddiku Malami , Abdullahi Kabiru
Published: August 2018

Background: Urinary Bladder Cancer is a common disease worldwide. It ranks ninth in cancer incidence and is the 13th leading cause of cancer death among men and women worldwide. The highest incidence is seen usually in developed countries. In our environment, it is the leading cause of cancer and cancer deaths among males because of endemicity of urinary schistosomiasis. Yet, little is done to curb this preventable risk factor of bladder cancer.

Objective: The objectives of this study were to describe histopathological pattern of urinary bladder cancer in Sokoto, Northwestern Nigeria.

Method: This was a retrospective study of all histologically confirmed cases of bladder cancer seen at the Department of Histopathology, Usmanu Danfodiyo University Teaching Hospital, Sokoto between the years 2006 and 2015. Information was obtained from the database of the Department of Histopathology. The data were validated using Microsoft Excel and exported to SPSS for analysis. The data were analysed for age, sex and histological types using SPSS version 20 software. The results are presented in the form of simple frequency tables and percentages.

Results: A total of 190 patients were seen with histologically confirmed bladder cancer out of the 3933 patients with malignancies between the years 2006 and 2015, constituting 4.8% of all malignancies diagnosed in the same period and comprises 160(84.2%) males and 30(15.8%) females with male to female ratio of 5.3:1. Their mean age was 50.8, SD ±14.9 years and range from 1-90 years. The most common bladder cancer was squamous cell carcinoma with 97 (51.1%) cases. 81 (42.6%) patients had urothelial carcinoma, 5(2.6%) were metastatic carcinoma, 4(2.1%) were sarcomatoid carcinoma, 2(1.1%) were rhabdomyosarcoma and only 1(0.5%) case of a signet ring cell carcinoma was recorded.

Conclusion: Squamous cell carcinoma remained the most common histological type of bladder cancer in our setting followed by urothelial carcinoma. Preventive measures aim at eradicating urinary schistosomiasis, a predominant and known risk factor of bladder cancer in our environment will go a long way in curtailing the burden of this disease among our people.

Citation Format: Saddiku Malami Sahabi, Kabiru Abdullahi. Urinary bladder cancer in Sokoto, Northwestern Nigeria: A 10-year histopathological review [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1212.
Abstract 1222: Functional single-nucleotide polymorphisms in the TGFb and TGFbRI gene and their association with prostate cancer in Western Mexicans
Authors: Martínez-Rizo Abril , González-Cordova Brenda , Peña-George Christopher , (CA-UAN-266) Cuerpo Académico de Investigación Bioquímica , Navarro-Partida José , González-Carrillo Martha , Arvizu-Gómez Jackeline , Álvarez-Rodríguez Adriana
Published: August 2018

Background: Prostatic carcinogenesis has been linked to chronic inflammation. Several studies demonstrated the duality of TGFβ during carcinogenesis. This pleiotropic cytokine participates in cell proliferation, migration and survival, epithelial-mesenchymal transition, and apoptosis, among other functions. An increase in its expression is associated with antiproliferative effects, tumor angiogenesis and metastasis of cancer cells. Single-nucleotide polymorphisms (SNPs) of the TGFB1 and TGFBR1 genes have been associated with risk and progression of many cancers.

Aim: To investigate the synergic role T29C (rs1800470) of the TGFβ gene and TGFBR1 rs334348 polymorphisms in risk, progression and severity of prostate cancer.

Materials and Methods: The present cases-control study includes 211 patients with PCa, and as controls 297 patients with benign prostatic hyperplasia (BPH) were obtained. The functional polymorphisms rs1800470 of the TGFβ gene and TGFBR1 rs334348 were detected by real-time PCR using the TaqMan probe system, according to the manufacturer's amplification recommendations. Hardy Weinberg Equilibrium was calculated by chi-square (χ2) test. Odds ratios (ORs) and 95% confidence intervals (95% CIs) for each SNP were calculated. The haplotypes were analyzed using the Haploview program.

Results: The genotype frequencies of the SNPs analyzed in this work were no significant deviation from Hardy-Weinberg Equilibrium. Chi-square analysis established that there was no significant association between prostate cancer risk and TGFβ or TGFBR1 genotypes and alleles. Neither of the polymorphisms was associated with progression or severity of prostate cancer. Furthermore, the GT haplotype revealed protection for development of prostate cancer (OR=0.57, 95% CI (0.36-0.89) p=0.01).

Conclusion: To our knowledge, this research is the first genetic association study to show that GT haplotype confers protection in patients from Western Mexico with PCa.

Citation Format: Abril Martínez-Rizo, Brenda González-Cordova, Christopher Peña-George, Cuerpo Académico de Investigación Bioquímica (CA-UAN-266), José Navarro-Partida, Martha González-Carrillo, Jackeline Arvizu-Gómez, Adriana Álvarez-Rodríguez. Functional single-nucleotide polymorphisms in the TGFb and TGFbRI gene and their association with prostate cancer in Western Mexicans [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1222.
Abstract 1232: Familial mesothelioma: Beyond BAP1
Authors: Cheung Mitchell , Ohar Jill A. , Howard Suzanne E. , Howard Timothy D. , Hesdorffer Mary , Testa Joseph R.
Published: August 2018

BAP1 germline mutations are associated with some, but not all, familial malignant mesotheliomas. We sought to identify new genetic risk factors from a large cohort of malignant mesotheliomas cases with a family history of cancers but no germline BAP1 mutation. Whole genome sequencing was performed on 15 samples (14 peripheral blood and 1 MM sample). Promising mutated candidate genes were identified in 12 of 14 BAP1 mutation-negative cases, with 3 different candidate genes mutated in 3 cases, 2 different candidates mutated in 5 cases, and 1 candidate mutated in 4 cases. Candidate genes encoded proteins involved in DNA damage repair, DNA polymerase, DNA and histone methytransferase, as well as mitotic control, helicase, and kinase factors. All mutations were confirmed by Sanger sequencing. Mutations included in/dels predicting frameshifts (4), splice site mutations (6), and missense mutations (14). Notably, in addition to being BAP1 mutation-negative, germline mutations were not identified in any of the genes known to be commonly mutated somatically in malignant mesothelioma, i.e., CDKN2A, NF2, TP53, SETD2, or PBRM1. Sequencing of blood and/or tumor DNA from several available affected members of these families validated co-segregation of mutations in candidate genes with the development of various cancers. Malignant mesothelioma specimens from two members of one family showed somatic loss of heterozygosity of the wild-type allele, indicating biallelic inactivation of the candidate gene—a suspected tumor suppressor locus—in these tumors.

Citation Format: Mitchell Cheung, Jill A. Ohar, Suzanne E. Howard, Timothy D. Howard, Mary Hesdorffer, Joseph R. Testa. Familial mesothelioma: Beyond BAP1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1232.
Abstract 1234: Somatic mutations of FAT1 in oral cancer are associated with tumor progression and survival
Authors: Liu Chung Ji , Lin Shu-Chun , Lin Li-Han
Published: August 2018

In recent years, the incidence and mortality rates of oral squamous cell carcinoma (OSCC) have increased worldwide. Therefore, understanding genomic alterations in OSCC carcinogenesis is crucial for appropriate diagnosis and therapy. Procadherin FAT1, which encodes 4588 amino acid residues, regulates complex mechanisms to promote oncogenesis or suppression of malignancies. Multiplex polymerase chain reaction (PCR)-based next-generation sequencing (NGS) revealed FAT1 somatic mutations. The clinicopathologic implications of FAT1 in OSCC were investigated using expression assays, and the functional role of FAT1 in HNSCC pathogenesis was determined using ectopic expression and knockdown experiments. Approximately 29% of patients with OSCC harbored damaging FAT1 mutations. Each type of mutation (missense, nonsense, and frameshift mutations) accounted for nearly one-third of deleterious mutations. FAT1 mutations correlated with lower FAT1 expression in tumors. The knockdown of the endogenous expression of FAT1 and exogenous expression of crucial FAT1 domains unequivocally indicated that FAT1 suppressed the migration and invasion capability of OSCC cells. Functional analysis suggested that nonsense mutations in FAT1 result in the loss of the suppression of tumor progression. FAT1 mutations and downregulation defined nodal involvement, lymphovascular permeation, and tumor recurrence. In addition, FAT1 mutations and downregulation are independent predictors of poor disease-free survival in patients with HNSCC. This study is the first to perform multiplex PCR-based NGS to indicate marked nonsynonymous FAT1 mutations in OSCC, which are prognostic indicators. The gene analysis strategy proposed for detecting FAT1 mutations may be a valid method for mutation screening.

Citation Format: Chung Ji Liu, Shu-Chun Lin, Li-Han Lin. Somatic mutations of FAT1 in oral cancer are associated with tumor progression and survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1234.
Abstract 1247: Hereditary paraganglioma-pheochromocytoma syndrome: Patterns of presentation in a Brazilian oncogenetics clinic
Authors: Soares Diogo C. , Camacho Ana Milena G. , Achatz Maria Isabel , Formiga Maria Nirvana C.
Published: August 2018

Introductory Sentence: More than 35% of pheochromocytomas and paragangliomas (PPGL) are thought to occur due to an underlying genetic predisposition, which explain approximately 30% of familial cases. Methods: We analyzed data of four families with clinical and molecular diagnosis of PPGL followed at Oncogenetics Department of A.C. Camargo Cancer Center, from 2010 to 2017. Results: The proband of Family 1 is a 40-year-old woman with glomus jugulare paraganglioma and confirmed SDHB mutation. Her two children have the same mutation in SDHB gene and her son had the diagnosis of retroperitoneal paraganglioma at the age 13. The brother of the index case had a pheochromocytoma and her nephew had an abdominal paraganglioma at the age of 8. In the Family 2 the index case is a 33-year-old woman with paraganglioma of the carotid body bilateral and had a molecular diagnosis with SDHB mutation. There are no other paraganglioma cases in the members of this family. Family 3 initiated counseling in our clinics with a woman with paraganglioma of the carotid body bilateral at 25-year-old with recurrence at 35-year-old and it was found in genetic test a SDHD mutation. She had two cousins with bilateral cervical paraganglioma, but without genetic testing. Our fourth family: Man with pheochromocytoma at 28-year-old and mutation in the SDHD gene. A son with metastatic phaeochromocytoma in the retroperitoneum, mediastinum and lung at 11-year-old and bilateral carotid paraganglioma at 12-year-old. Sister of the index case with glomus jugulare paraganglioma at the age of 38. Conclusions: Although PPGL are rare tumors, it is estimated that up to 30-40% of cases are hereditary, based on this it is relevant to raise the PPGL syndrome suspicion and refer a paraganglioma or pheochromocytoma patient to a cancer genetic counseling. There are clear follow-up guidelines for the early detection of these tumors in carriers and the genotype-phenotype correlation can direct the diagnosis and in some cases the management of these patients.

Citation Format: Diogo C. Soares, Ana Milena G. Camacho, Maria Isabel Achatz, Maria Nirvana C. Formiga. Hereditary paraganglioma-pheochromocytoma syndrome: Patterns of presentation in a Brazilian oncogenetics clinic [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1247.
Abstract 1254: Metformin's potential as a breast cancer preventative agent by altering epigenetic patterns
Authors: Tyndall Caitriona , Lam Charlene , Gunter Marc , Flanagan James
Published: August 2018

Metformin is one of the most commonly prescribed Type II Diabetes Mellitus (T2DM) drugs and has been shown in diabetic long-term users to reduce the likelihood of breast cancer by 56%. Breast cancer is the most commonly diagnosed cancer in the UK accounting for 55,000 new cases per year. It has been estimated that as much as 27% of cases could be prevented based on current knowledge. This study aims to investigate the novel hypothesis that metformin acts as a preventative agent by altering epigenetic patterns in non-cancerous breast epithelial cells and the T2DM environment, namely hyperinsulinemia and hyperglycaemia, potentially modulates this.

Crystal Violet cell viability assay and Western Blot for p-AMPK, a known target for metformin, were performed to assess the response of two non-cancerous breast epithelial cells lines, MCF10A and MCF12A, to metformin in a range of insulin and glucose concentrations. Western blot was performed to assess changes in histone post-translational modifications (PTMs), such as H2K27ac and H3K27me3, following 3-days treatment with metformin at 2.5mM and 5mM. Additionally, we conducted an Illumina MethylationEPIC Array on MCF10A and MCF12A cell lines treated for 3-days with 2.5mM and 5mM metformin. Pyrosequencing assay was used to further validate interesting CpG sites.

Our findings suggest non-cancerous breast epithelial cells, MCF10A and MCF12A cell lines, are sensitive to metformin following 3 and 7-days treatment. Further to this, our data suggests the T2DM environment impacts the effectiveness of metformin where low glucose and high insulin significantly increase metformin effectiveness in MCF10A and MCF12 cell lines following 3-day treatment, respectively. Metformin treatment leads to the activation of p-AMPK in normal breast epithelial cells. Analysis of Illumina MethylationEPIC array suggests metformin in hyperglycaemic and hyperinsulinemic conditions induces differential DNA methylation changes in MCF10A and MCF12A non-cancerous breast epithelial cell lines and the effects are dose dependent. Of the 850,000 probes, 13 CpG sites in MCF10A and 5 CpG sites in MCF12A showed significant changes in methylation following metformin treatment (p<0.001).

In summary, this study has shown a potential mechanism of metformin action through altering of epigenetic patterns in non-cancerous breast epithelial cells. Future work aims to further explore epigenetic changes induced by metformin in the context of the T2DM environment and whether these changes could potentially predict reduced breast cancer risk.

Citation Format: Caitriona Tyndall, Charlene Lam, Marc Gunter, James Flanagan. Metformin's potential as a breast cancer preventative agent by altering epigenetic patterns [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1254.
Abstract 1259: Loss of TFF1 promotes growth and chemotherapeutic resistance in gastric cancer
Authors: Chen Zheng , Li Zheng , Soutto Mohammed , Wang Weizhi , Zhu Shoumin , Corvalan Alejandro , Xu Zekuan , El-Rifai Wael
Published: August 2018

Background: Downregulation or loss of TFF1 expression occurs in more than half of human gastric adenocarcinomas through gene deletions, mutation, and a loss of heterozygosity or hypermethylation. Our previous studies have shown that Tff1 knockout (KO) in mice induces gastric lesions from low- grade dysplasia (LGD), high- grade dysplasia (HGD) to adenocarcinoma. BRD2, a family member of BET proteins, promotes aberrant gene expression in a variety of malignant tumors. In this study, with the analysis of Tff1 KO mice and human gastric cancer tissue samples, we discovered that loss of Tff1 promotes gastric cancer proliferation and drug resistance through upregulating BRD2 expression level.

Methods and Results: Integration Next Generation Sequencing data analysis in both Tff1 KO mice and human gastric cancer tissue samples demonstrated that miR-143-3p was significantly down-regulated in both mice and human gastric cancer samples (P<0.05). Our findings were further validated by RT-PCR in Tff1 KO mouse gastric legions (LGD and adenocarcinoma) and 3 different cohorts of human gastric cancer tissue samples from USA, Chile, and China. Using different gastric cancer cell models we further confirmed the decrease of miR-143-3p regulated by loss of TFF1. Next, we wanted to find out the downstream effector of miR-143-3p down-regulation. Western blot data showed that BRD2 protein level was regulated by miR-143-3p in 4 gastric cancer cell lines. BRD2 3'UTR luciferase reporter assay further confirmed that miR-143-3p decreased BRD2 protein expression through directly binding to its 3'UTR sites. These data suggested that, for the first time, BRD2 is a direct downstream target of miR-143-3p. At the meantime, the reconstitution of TFF1 in gastric cancer cells up-regulated miR-143-3p expression level, which in turn, decreased the protein expression levels of BRD2, MYC and BCL-2. Using western blot, we showed the synergistic effect of BRD2 inhibitor and CDDP chemotherapy in human gastric cancer cells. Data from 320 human gastric cancer patients demonstrated that high BRD2 expression level in gastric cancer tissues significantly decreased the overall patient survival rate (P<0.0001).

Conclusion: This study unveils, for the first time, loss of TFF1 promotes BRD2 activation in gastric cancer through decreasing miR-143-3p. This axis presents novel therapeutic opportunities by using approaches that reconstitute miR-143-3p or utilizing the recently developed clinical trials in human gastric cancer.

Citation Format: Zheng Chen, Zheng Li, Mohammed Soutto, Weizhi Wang, Shoumin Zhu, Alejandro Corvalan, Zekuan Xu, Wael El-Rifai. Loss of TFF1 promotes growth and chemotherapeutic resistance in gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1259.
Abstract 126: MYC-driven lymphomas suppress NK surveillance by blocking maturation of early NK cells
Authors: Heftdal Line D. , Swaminathan Srividya , Felsher Dean W.
Published: August 2018

The MYC oncogene is commonly overexpressed in hematopoietic cancers. In a transgenic mouse model of MYC-induced T-cell lymphoma, we found that there was a systemic reduction in NK cell (CD3- NKp46High) numbers and activation in lymphoid organs such as spleen and bone marrow. MYC inactivation in lymphoma-bearing MYCON mice partially restored NK cell numbers and activation. Hence, the MYC oncogene appears to suppress NK cell-mediated immune surveillance of lymphomas. We evaluated whether reduction in mature and activated NK cells (CD3- NKp46High) in MYCON mice was due to increased death of NK cells in these mice when compared to normal and MYCOFF mice. Using flow cytometry, NK cells were measured in age matched spleens and bone marrows of normal (n = 8), MYCON (n = 8), and MYCOFF (n = 8) mice. Surprisingly, we observed a significant reduction in proportions of dead NK cells (NKp46+ PI+) in spleen and bone marrow of MYCON mice, in comparison to normal and MYCOFF cohorts. Hence, the reduction in activated NK cell numbers during MYC-driven lymphomagenesis does not occur because of increased death of NK cells. Next, we investigated whether MYC arrests early NK cell development in the bone marrow of lymphoma mice, leading to systemic NK suppression. NK cell lineage specification begins with CD122 expression, that is maintained throughout NK development starting at the precursor stage. NK precursors (NKP) transition to immature NK (iNK) cells by expressing the cytotoxicity marker NKp46. iNK cells leave the bone marrow to populate peripheral lymphoid organs. We measured NKP (CD122+ NKP46-), and iNK (CD122+ NKp46+) cells in bone marrow of normal (n = 8), MYCON (n = 8), and MYCOFF (n = 8) mice. We observed no significant changes in the percentages of NKP. However, the proportions of iNK cells were significantly reduced in MYCON mice, in comparison to MYCOFF and normal mice. Our results suggest that MYC may block transition from NKP to iNK stage during early NK cell development. The reduction of iNK cells in spleens of MYCON mice was concordant with the reduction of iNK cells in bone marrow from the same mice. We conclude that MYC-induced lymphomagenesis blocks early NK cell development, thereby suppressing NK-mediated immune surveillance.

Citation Format: Line D. Heftdal, Srividya Swaminathan, Dean W. Felsher. MYC-driven lymphomas suppress NK surveillance by blocking maturation of early NK cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 126.
Abstract 1264: Commensal microbiota is involved in anti-PD-1 mAb-mediated antitumor activity in a preclinical tumor model
Authors: Chen Fei , Ding Jian , Gu Xiangchao , Zhang Juan , Yang wenqing , Shi Qian
Published: August 2018

Background: A number of studies have shown that the gut microbiome may influence anti-tumor immune responses via innate and adaptive immunity, and the recent work in mice has highlighted the key roles of the gut microbiota in mediating tumor responses to chemotherapeutic agents and immunotherapies targeting PD-L1, PD-1 or CTLA-4. Multiple studies have demonstrated that the gut microbiome can markedly influence the outcome of PD-1 blockade in mice and patients and several commensal have been proved to be associated with favorable clinical outcome. Considering complexity of intestinal micro-organisms, a larger panel or wider spectrum of microbiota species maybe involved in this process.

Methods: Since compositional differences in the microbiome may influence cancer development and responses to therapies, we sought to determine whether intestinal bacterial composition and abundances of the tumor bearing mice were associated with a specific treatment outcome of immunotherapy. To test this, we analyzed and compared an enrichment of intestinal microbiota of CT26 syngeneic tumor bearing mice before and after a series of anti-PD-1 mAb treatment were given.

Results The results demonstrating that some strains were robustly enriched and this enrichment was associated with tumor response to anti-PD 1 therapy, while as other strains were down regulated upon the checkpoint blockade.

Conclusions: Upon further characterization and confirmation, these intriguing findings could lead to identification of one or more microbiota strains that could have biomarker potentials or therapeutic values for cancer immunotherapy.

Citation Format: Fei Chen, Jian Ding, Xiangchao Gu, Juan Zhang, wenqing Yang, Qian Shi. Commensal microbiota is involved in anti-PD-1 mAb-mediated antitumor activity in a preclinical tumor model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1264.
Abstract 127: Exosomes derived from head and neck cancer enhance the cytotoxicities of NK cells by NAP1-IRF-3 pathway
Authors: Chen Wantao , Wang Yingnan , Zhang Jianjun
Published: August 2018

Objective: To examine the effect of tumor-derived exosomes (TEXs) from oral cancer on natural killer (NK) cells and to explore the underlying mechanism.

Materials and Methods: TEXs were isolated from the medium supernatant of oral cancer (OC) cells using ultrafiltration and affinity chromatography and were identified using electronic microscopy, nanoparticle tracking analysis and immunoblotting. The effects of TEXs on NK cells were analyzed using laser scanning confocal microscopy and several functional assays of NK cells. To explore the mechanism, antibody array, protein mass spectrometry and RNA interference were adopted.

Results: The particles isolated from the OC cells were identified as exosomes with satisfactory morphology, concentration and purity. The TEXs were internalized by the NK cells and then promoted the biologic functions of these cells, including proliferation, cytotoxicity and the release of perforin and granzyme M. Furthermore, we found that the TEXs increased the expression of interferon regulatory factor 3 (IRF-3) and phosphorylated IRF-3 by antibody array, which drove the expression of the type I interferon (IFN) gene and the chemokine (C-X-C motif) ligand (CXCL) genes, thereby promoting the function of NK cells. We also found that NF-κB-activating kinase-associated protein 1 (NAP1), an upstream activator of IRF-3, was enriched in TEXs, and treatment with TEXs increased NAP1 in NK cells. Importantly, NAP1-depleted TEXs obtained from OC cells dramatically weakened the influence of the TEXs on NK cells.

Conclusion: Our findings reveal a previously unrecognized function of exosome derived from oral cancer cells in enhancing the cytotoxicity of NK cells by NAP1- IRF-3 pathway.

This work was supported by the National Program on Key Research Project of China (2016YFC0902700).

Citation Format: Wantao Chen, Yingnan Wang, Jianjun Zhang. Exosomes derived from head and neck cancer enhance the cytotoxicities of NK cells by NAP1-IRF-3 pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 127.
Abstract 1274: Effects of diet on lung adenoma carcinogenesis in metformin treated A/J mice
Authors: Souksavong Vannesa , Wuertz Beverly R. , Seabloom Donna , Ondrey Frank G.
Published: August 2018

There has been considerable interest in the effects of biguanides, utilized to treat type 2 diabetes, on human carcinogenesis. Several population studies established diabetes patients treated with metformin and other type 2 diabetes agents experience decreased cancers in several organ systems. However, the effects are not universal in all organ systems and metabolically complex. In the present study, we utilized a dosing regimen of dietary metformin in benzo[a]pyrene treated mice known to reduce lung adenoma formation in A/J mice by approximately 50% over controls. For the duration of this study we used several animal diets commonly employed for mouse chemoprevention experiments with and without 850 mg/kg/day metformin added to the diet. These included AIN93M, AIN76A, D62 (Dr. Lee Wattenberg's chemoprevention diet), a modification of D62 with added maltodextrin and sucrose, and Teklad 4% fat pellets from Envigo. At the conclusion of the study, animals were sacrificed and surface adenoma counts were performed on fresh lungs from each group of animals. We found 850 mg/kg/day metformin for 16 weeks reduced adenoma formation by 35-60% in the diets we employed for the study. Interestingly, the Teklad diet which contains dehulled soybean meal had significantly reduced tumor formation in the control animals, demonstrating some animal diets provide chemoprevention efficacy independent of any pharmaceutical effects. There was no observed toxicity of metformin in the animals; however we have observed significant differences in the average end weights of animals treated with metformin. We conclude metformin is an efficacious agent in lung adenoma chemoprevention and similar reductions in adenoma formation occurred in several of the diets commonly employed for chemoprevention studies in B[a]P treated mice. However, attention to diet formulation is vital due to potential chemoprevention and metabolic effects independent of metformin treatment.

Citation Format: Vannesa Souksavong, Beverly R. Wuertz, Donna Seabloom, Frank G. Ondrey. Effects of diet on lung adenoma carcinogenesis in metformin treated A/J mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1274.