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KDM5B (lysine[K]-specific demethylase 5B) is frequently upregulated in various human cancers including prostate cancer. KDM5B controls H3K4me3/2 levels and regulates gene transcription and cell differentiation, yet the contributions of KDM5B to prostate cancer tumorigenesis remain unknown. In this study, we investigated the functional role of KDM5B in epigenetic dysregulation and prostate cancer progression in cultured cells and in mouse models of prostate epithelium–specific mutant Pten/Kdm5b. Kdm5b deficiency resulted in a significant delay in the onset of prostate cancer in Pten-null mice, whereas Kdm5b loss alone caused no morphologic abnormalities in mouse prostates. At 6 months of age, the prostate weight of Pten/Kdm5b mice was reduced by up to 70% compared with that of Pten mice. Pathologic analysis revealed Pten/Kdm5b mice displayed mild morphologic changes with hyperplasia in prostates, whereas age-matched Pten littermates developed high-grade prostatic intraepithelial neoplasia and prostate cancer. Mechanistically, KDM5B governed PI3K/AKT signaling in prostate cancer in vitro and in vivo. KDM5B directly bound the PIK3CA promoter, and KDM5B knockout resulted in a significant reduction of P110α and PIP3 levels and subsequent decrease in proliferation of human prostate cancer cells. Conversely, KDM5B overexpression resulted in increased PI3K/AKT signaling. Loss of Kdm5b abrogated the hyperactivation of AKT signaling by decreasing P110α/P85 levels in Pten/Kdm5b mice. Taken together, our findings reveal that KDM5B acts as a key regulator of PI3K/AKT signaling; they also support the concept that targeting KDM5B is a novel and effective therapeutic strategy against prostate cancer.Significance:This study demonstrates that levels of histone modification enzyme KDM5B determine hyperactivation of PI3K/AKT signaling in prostate cancer and that targeting KDM5B could be a novel strategy against prostate cancer.

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As data grows exponentially across diverse fields, the ability to effectively leverage big data has become increasingly crucial. In the field of data science, however, minority groups, including African Americans, are significantly underrepresented. With the strategic role of minority-serving institutions to enhance diversity in the data science workforce and apply data science to health disparities, the National Institute for Minority Health Disparities (NIMHD) provided funding in September 2021 to six Research Centers in Minority Institutions (RCMI) to improve their data science capacity and foster collaborations with data scientists. Meharry Medical College (MMC), a historically Black College/University (HBCU), was among the six awardees. This paper summarizes the NIMHD-funded efforts at MMC, which include offering mini-grants to collaborative research groups, surveys to understand the needs of the community to guide project implementation, and data science training to enhance the data analytics skills of the RCMI investigators, staff, medical residents, and graduate students. This study is innovative as it addressed the urgent need to enhance the data science capacity of the RCMI program at MMC, build a diverse data science workforce, and develop collaborations between the RCMI and MMC’s newly established School of Applied Computational Science. This paper presents the progress of this NIMHD-funded project, which clearly shows its positive impact on the local community.

Genomic medicine holds great promise for improving health care, but integrating searchable and actionable genetic data into electronic health records (EHRs) remains a challenge. Here we describe Neptune, a system for managing the interaction between a clinical laboratory and an EHR system during the clinical reporting process. We developed Neptune and applied it to two clinical sequencing projects that required report customization, variant reanalysis, and EHR integration. Neptune has been applied for the generation and delivery of over 15,000 clinical genomic reports. This work spans two clinical tests based on targeted gene panels that contain 68 and 153 genes respectively. These projects demanded customizable clinical reports that contained a variety of genetic data types including single-nucleotide variants (SNVs), copy-number variants (CNVs), pharmacogenomics, and polygenic risk scores. Two variant reanalysis activities were also supported, highlighting this important workflow. Methods are needed for delivering structured genetic data to EHRs. This need extends beyond developing data formats to providing infrastructure that manages the reporting process itself. Neptune was successfully applied on two high-throughput clinical sequencing projects to build and deliver clinical reports to EHR systems. The software is open source and available at https://gitlab.com/bcm-hgsc/neptune .

This study examined longitudinal education and career outcomes of the Meharry-Vanderbilt-Tennessee State University Cancer Partnership, the longest-running National Cancer Institute (NCI) Comprehensive Partnerships in Advancing Cancer Health Equity (CPACHE) program site in the United States. Degree completion rates were calculated and progression along the entire postsecondary "pipeline" was quantified for 204 participants recruited between 2011 and 2020. For participants who had entered the workforce, career outcomes were also analyzed. Relative to comparison data, participants completed degrees and progressed through the higher education "pipeline" to earn advanced degrees at remarkably high rates; the majority entered careers in which they support or conduct cancer research. The latter is important, because most participants identify with demographic categories currently underrepresented in the cancer research workforce. This article makes two contributions to knowledge on research training programs for underrepresented students: 1) it quantifies participants' progression along the entire postsecondary education pipeline as well as into the workforce, and 2) it identifies points where participants are most prone to exit the pipeline rather than progress. We identify two types of exits-permanent and temporary-and offer empirically supported operational definitions for both. Evaluators may find the quantitative model and/or definitions useful for analyzing similar programs.

Simple Summary Obesity contributes to one-fifth of cancer deaths. Ovarian cancer (OC) progression is frequently asymptomatic, making its early detection difficult and its chance of survival low. OC expresses highly tumorigenic chemokines, CXCL1/8, of which the specific receptor CXCR2 is increased in the adipocytes. So, the CXCL1/8-CXCR2 axis may appear as a molecular link between obesity and OC. Here, we generated adipocyte-specific CXCR2 conditional knockout (cKO) mice to investigate how this CXCR2 cKO affects the peritoneal dissemination of OC under obese conditions. High-fat, diet-induced obese mice had a shorter survival than lean mice. Particularly, obese cKO mice had a reduced tumor burden but increased ascites accumulation, showing a decreased floating tumor burden in ascites, as well as proliferation and macrophage infiltration in tumors compared to obese wild-type mice. Despite the ascites accumulation, adipocyte-specific CXCR2 cKO reduced the obesity-induced tumor burden, likely altering the peritoneal tumor microenvironment of OC. Abstract Obesity contributes to ovarian cancer (OC) progression via tumorigenic chemokines. Adipocytes and OC cells highly express CXCR2, and its ligands CXCL1/8, respectively, indicating that the CXCL1/8-CXCR2 axis is a molecular link between obesity and OC. Here, we investigated how the adipocyte-specific CXCR2 conditional knockout (cKO) affected the peritoneal tumor microenvironment of OC in a high-fat diet (HFD)-induced obese mouse model. We first generated adipocyte-specific CXCR2 cKO in mice: adipose tissues were not different in crown-like structures and adipocyte size between the wild-type (WT) and cKO mice but expressed lower levels of CCL2/6 compared to the obese WT mice. HFD-induced obese mice had a shorter survival time than lean mice. Particularly, obese WT and cKO mice developed higher tumors and ascites burdens, respectively. The ascites from the obese cKO mice showed increased vacuole clumps but decreased the floating tumor burden, tumor-attached macrophages, triglyceride, free fatty acid, CCL2, and TNF levels compared to obese WT mice. A tumor analysis revealed that obese cKO mice attenuated inflammatory areas, PCNA, and F4/80 compared to obese WT mice, indicating a reduced tumor burden, and there were positive relationships between the ascites and tumor parameters. Taken together, the adipocyte-specific CXCR2 cKO was associated with obesity-induced ascites despite a reduced tumor burden, likely altering the peritoneal tumor microenvironment of OC.

Sterol regulatory element-binding protein 1 (SREBP-1), a master transcription factor in lipogenesis and lipid metabolism, is critical for disease progression and associated with poor outcomes in prostate cancer (PCa) patients. However, the mechanism of SREBP-1 regulation in PCa remains elusive. Here, we report that SREBP-1 is transcriptionally regulated by microRNA-21 (miR-21) in vitro in cultured cells and in vivo in mouse models. We observed aberrant upregulation of SREBP-1, fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC) in Pten/Trp53 double-null mouse embryonic fibroblasts (MEFs) and Pten/Trp53 double-null mutant mice. Strikingly, miR-21 loss significantly reduced cell proliferation and suppressed the prostate tumorigenesis of Pten/Trp53 mutant mice. Mechanistically, miR-21 inactivation decreased the levels of SREBP-1, FASN, and ACC in human PCa cells through downregulation of insulin receptor substrate 1 (IRS1)-mediated transcription and induction of cellular senescence. Conversely, miR-21 overexpression increased cell proliferation and migration; as well as the levels of IRS1, SREBP-1, FASN, and ACC in human PCa cells. Our findings reveal that miR-21 promotes PCa progression by activating the IRS1/SREBP-1 axis, and targeting miR-21/SREBP-1 signaling pathway can be a novel strategy for controlling PCa malignancy.

The advancement of precision medicine requires new methods to coordinate and deliver genetic data from heterogeneous sources to physicians and patients. The eMERGE III Network enrolled >25,000 participants from biobank and prospective cohorts of predominantly healthy individuals for clinical genetic testing to determine clinically actionable findings. The network developed protocols linking together the 11 participant collection sites and 2 clinical genetic testing laboratories. DNA capture panels targeting 109 genes were used for testing of DNA and sample collection, data generation, interpretation, reporting, delivery, and storage were each harmonized. A compliant and secure network enabled ongoing review and reconciliation of clinical interpretations, while maintaining communication and data sharing between clinicians and investigators. A total of 202 individuals had positive diagnostic findings relevant to the indication for testing and 1,294 had additional/secondary findings of medical significance deemed to be returnable, establishing data return rates for other testing endeavors. This study accomplished integration of structured genomic results into multiple electronic health record (EHR) systems, setting the stage for clinical decision support to enable genomic medicine. Further, the established processes enable different sequencing sites to harmonize technical and interpretive aspects of sequencing tests, a critical achievement toward global standardization of genomic testing. The eMERGE protocols and tools are available for widespread dissemination.

Acute-phase proteins (APPs) are associated with a variety of disorders such as infection, inflammatory diseases, and cancers. The signature profile of APPs in breast cancer (BC) is poorly understood. Here, we identified serum amyloid A (SAA) for proinflammatory predisposition in BC through the signature profiles of APPs, interleukin (IL) and tumor necrosis factor (TNF) superfamily using publicly available datasets of tumor samples and cell lines. Triple-negative breast cancer (TNBC) subtype highly expressed SAA1/2 compared to HER2, luminal A (LA) and luminal B (LB) subtypes. IL1A, IL1B, IL8/CXCL8, IL32 and IL27RA in IL superfamily and CD70, TNFSF9 and TNFRSF21 in TNF superfamily were highly expressed in TNBC compared to other subtypes. SAA is restrictedly regulated by nuclear factor (NF)-κB and IL-1β, an NF-κB activator highly expressed in TNBC, increased the promoter activity of SAA1 in human TNBC MDA-MB231 cells. Interestingly, two κB-sites contained in SAA1 promoter were involved, and the proximal region (−96/−87) was more critical than the distal site (−288/−279) in regulating IL-1β-induced SAA1. Among the SAA receptors, TLR1 and TLR2 were highly expressed in TNBC. Cu-CPT22, TLR1/2 antagonist, abrogated IL-1β-induced SAA1 promoter activity. In addition, SAA1 induced IL8/CXCL8 promoter activity, which was partially reduced by Cu-CPT22. Notably, SAA1/2, TLR2 and IL8/CXCL8 were associated with a poor overall survival in mesenchymal-like TNBC. Taken together, IL-1-induced SAA via NF-κB-mediated signaling could potentiate an inflammatory burden, leading to cancer progression and high mortality in TNBC patients.

Human Interlekin-17 is produced by memory activated CD4+ T cells and other cells. It was initially considered unique in that its specific receptor is distinct from other cytokine receptors. IL-17 receptor is ubiquitously expressed by different cells including T cells. IL-17 plays a role in regulating growth, immune response and pro-inflammatory responses. It regulates differentiation of a subset of Th0 cells into Th-17 cells, which produce IL-17-induced cytokines. The IL-17R belongs to type 1 cytokine receptors. IL-17 belongs to a superfamily of its own, which includes IL-17A, IL-17B, IL-17C, IL-17E and IL-17F. These members of IL-17 superfamily have some sequence homology but bind to different receptors. Prior to this investigation, limited information existed on the effects of IL-17A in human leukemia cell lines. Our results show that IL-17A promotes growth, anti-apoptotic effects, chemotaxis, cytokine expression and transcriptional factor activation in leukemia cells. IL-17A activates multiple signaling pathways including PI-3 K, Jak–STAT, Raf-ERK1/2 and SRC kinase pathways, which mediate different biological effects of IL-17A in leukemia cells. Our findings implicate IL-17A in leukemia cell growth and survival, supporting potential leukemia therapy via development of anti-IL-17A drugs. This chapter focuses on IL-17A, herein referred to as IL-17.

KDM5B (lysine[K]-specific demethylase 5B) is frequently upregulated in various human cancers including prostate cancer. KDM5B controls H3K4me3/2 levels and regulates gene transcription and cell differentiation, yet the contributions of KDM5B to prostate cancer tumorigenesis remain unknown. In this study, we investigated the functional role of KDM5B in epigenetic dysregulation and prostate cancer progression in cultured cells and in mouse models of prostate epithelium–specific mutant Pten/Kdm5b. Kdm5b deficiency resulted in a significant delay in the onset of prostate cancer in Pten-null mice, whereas Kdm5b loss alone caused no morphologic abnormalities in mouse prostates. At 6 months of age, the prostate weight of Pten/Kdm5b mice was reduced by up to 70% compared with that of Pten mice. Pathologic analysis revealed Pten/Kdm5b mice displayed mild morphologic changes with hyperplasia in prostates, whereas age-matched Pten littermates developed high-grade prostatic intraepithelial neoplasia and prostate cancer. Mechanistically, KDM5B governed PI3K/AKT signaling in prostate cancer in vitro and in vivo. KDM5B directly bound the PIK3CA promoter, and KDM5B knockout resulted in a significant reduction of P110α and PIP3 levels and subsequent decrease in proliferation of human prostate cancer cells. Conversely, KDM5B overexpression resulted in increased PI3K/AKT signaling. Loss of Kdm5b abrogated the hyperactivation of AKT signaling by decreasing P110α/P85 levels in Pten/Kdm5b mice. Taken together, our findings reveal that KDM5B acts as a key regulator of PI3K/AKT signaling; they also support the concept that targeting KDM5B is a novel and effective therapeutic strategy against prostate cancer. Significance: This study demonstrates that levels of histone modification enzyme KDM5B determine hyperactivation of PI3K/AKT signaling in prostate cancer and that targeting KDM5B could be a novel strategy against prostate cancer.

The development of refractory tumor cells limits therapeutic efficacy in cancer by activating mechanisms that promote cellular proliferation, migration, invasion, metastasis, and survival. Benzimidazole anthelmintics have broad-spectrum action to remove parasites both in human and veterinary medicine. In addition to being antiparasitic agents, benzimidazole anthelmintics are known to exert anticancer activities, such as the disruption of microtubule polymerization, the induction of apoptosis, cell cycle (G2/M) arrest, anti-angiogenesis, and blockage of glucose transport. These antitumorigenic effects even extend to cancer cells resistant to approved therapies and when in combination with conventional therapeutics, enhance anticancer efficacy and hold promise as adjuvants. Above all, these anthelmintics may offer a broad, safe spectrum to treat cancer, as demonstrated by their long history of use as antiparasitic agents. The present review summarizes central literature regarding the anticancer effects of benzimidazole anthelmintics, including albendazole, parbendazole, fenbendazole, mebendazole, oxibendazole, oxfendazole, ricobendazole, and flubendazole in cancer cell lines, animal tumor models, and clinical trials. This review provides valuable information on how to improve the quality of life in patients with cancers by increasing the treatment options and decreasing side effects from conventional therapy.

The mechanisms by which exosomes (nano-vesicular messengers of cells) are taken up by recipient cells are poorly understood. We hypothesized that histones associated with these nano-particles are the ligands which facilitate their interaction with cell surface syndecan-4 (SDC4) to mediate their uptake. We show that the incubation with fetuin-A (exosome-associated proteins) and histones mediates the uptake of exosomes that are normally not endocytosed. Similarly, hydroxyapatite nanoparticles incubated with fetuin-A and histones (FNH) are internalized by tumor cells, while nanoparticles incubated with fetuin-A alone (FN) are not. The uptake of exosomes and FNH, both of which move to the perinuclear region of the cell, is attenuated in SDC4-knockdown cells. Data show that FNH can compete with exosomes for uptake and that both use SDC4 as uptake receptors.

Epidemiological surveys have revealed that environmental and dietary factors contribute to most of the human cancers. Our earlier studies have shown that resveratrol (RVT), a phytochemical reduced the tumor number, size and incidence of dysplasias induced by benzo(a)pyrene (BaP), an environmental toxicant in the Apc(Min/+) mouse model of colon cancer. In this study we investigated to ascertain whether the preventive effects of RVT on BaP-induced colon carcinogenesis is a result of altered BaP biotransformation by RVT. For the first group of mice, 100 μg BaP/kg bw was administered in peanut oil via oral gavage over a 60 day period. For the second group, 45 μg RVT/kg bw was co-administered with BaP. For the third group, RVT was administered for 1 week prior to BaP exposure. Blood, colon and liver were collected from control and BaP/RVT-treated mice at 60 days post-BaP & RVT exposure. We have assayed activities and expression (protein & mRNA) of drug metabolizing enzymes such as cytochrome P4501A1 (CYP1A1), CYP1B1, and glutathione-S-transferase (GST) in colon and liver samples from the treatment groups mentioned above. An increased expression of CYP1A1 in liver and colon and of CYP1B1 in liver of BaP-treated mice was seen, while RVT inhibited the extent of biotransformation mediated by these enzymes in the respective tissue samples. In the case of GST, an increased expression in colon of BaP alone-treated mice was noted when RVT was administered prior to BaP or simultaneously with BaP. However, there is no change in liver GST expression between BaP and RVT treatment groups. The concentrations of BaP aqueous (phase II) metabolites were found to be greater than the organic (phase I) metabolites, suggesting that RVT slows down the phase I metabolism (metabolic activation) of BaP, while enhancing phase II metabolism (detoxification). Additionally, the BaP-DNA adduct concentrations measured in colon and liver of BaP + RVT-treated mice were low relative to their BaP counterparts. Taken together, our findings strongly suggest that RVT alleviates BaP-induced colon carcinogenesis by impairing biotransformation pathways and DNA adduct formation, and therefore holds promise as a chemopreventive agent.

EZH2 is crucial for the progression of prostate cancer (PCa) and castration-resistant prostate cancer (CRPC) through upregulation and activation of progenitor genes, as well as androgen receptor (AR)-target genes. However, the mechanisms by which EZH2 is regulated in PCa and CRPC remain elusive. Here we report that EZH2 is post-transcriptionally regulated by SKP2 in vitro in cultured cells and in vivo in mouse models. We observed aberrant upregulation of Skp2, Ezh2 and histone H3 lysine 27 trimethylation (H3K27me3) in both Pten null mouse embryonic fibroblasts (MEFs) and Pten null mouse prostate tissues. Loss of Skp2 resulted in a striking decrease of Ezh2 levels in Pten/Trp53 double-null MEFs and in prostate tumors of Pten/Trp53 double-null mutant mice. SKP2 knockdown decreased EZH2 levels in human PCa cells through upregulation of TRAF6-mediated and lysine(K) 63-linked ubiquitination of EZH2 for degradation. Ectopic expression of TRAF6 promoted the K63-linked ubiquitination of EZH2 to decrease EZH2 and H3K27me3 levels in PCa cells. In contrast, TRAF6 knockdown resulted in a reduced EZH2 ubiquitination with an increase of EZH2 and H3K27me3 levels in PCa cells. Furthermore, the catalytically dead mutant TRAF6 C70A abolished the TRAF6-mediated polyubiquitination of recombinant human EZH2 in vitro. Most importantly, a concurrent elevation of Skp2 and Ezh2 was found in CRPC tumors of Pten/Trp53 mutant mice, and expression levels of SKP2 and EZH2 were positively correlated in human PCa specimens. Taken together, our findings revealed a novel mechanism on EZH2 ubiquitination and an important signaling network of SKP2-TRAF6-EZH2/H3K27me3, and targeting SKP2-EZH2 pathway may be a promising therapeutic strategy for CRPC treatment.

Impaired colon motility is one of the leading problems associated with inflammatory bowel disease (IBD). An expanding body of evidence supports the role of microbiome in normal gut function and in progression of IBD. The objective of this work is to determine whether diseased full thickness colon specimens, including the neuromuscular region (critical for colon motility function), contain specific oral and gut pathogens. In addition, we compared the differences in colon microbiome between Caucasians (CA) and African Americans (AA). Thirty-nine human full thickness colon (diseased colon and adjacent healthy colon) specimens were collected from Crohn's Colitis (CC) or Ulcerative Colitis (UC) patients while they underwent elective colon surgeries. We isolated and analyzed bacterial ribosomal RNA (rRNA) from colon specimens by amplicon sequencing of the 16S rRNA gene region. The microbiome proportions were quantified into Operational Taxonomic Units (OTUs) by analysis with Quantitative Insights Into Microbial ecology (QIIME) platform. Two hundred twenty-eight different bacterial species were identified by QIIME analysis. However, we could only decipher the species name of fifty-three bacteria. Our results show that proportion of non-detrimental bacteria in CC or UC colon samples were altered compared to adjacent healthy colon specimens. We further show, for the first time in full thickness colon specimens, that microbiome of CC and UC diseased specimens is dominated by putative oral pathogens belonging to the Phyla Firmicutes (Streptococcus, Staphylococcus, Peptostreptococcus), and Fusobacteria (Fusobacterium). In addition, we have identified patterns of differences in microbiome levels between CA and AA specimens with potential implications for health disparities research. Overall, our results suggest a significant association between oral and gut microbes in the modulation of colon motility in colitis patients.

Colon cancer ranks third in cancer related mortalities in the United States. Many studies have investigated factors that contribute to colon cancer in which dietary and environmental factors have been shown to play an integral role in the etiology of this disease. Specifically, human dietary intake of environmental carcinogens such as polycyclic aromatic hydrocarbons (PAHs) has generated interest in looking at how it exerts its effects in gastrointestinal carcinogenesis. Therefore, the objective of this study was to investigate the preventative effects of olive oil on benzo(a)pyrene [B(a)P]-induced colon carcinogenesis in adult ApcMin mice. Mice were assigned to a control (n =8) or treatment group (n =8) consisting of 25, 50 and 100 μg B(a)P/kg body weight (bw) dissolved in tricaprylin [B(a)P-only group] or olive oil daily via oral gavage for sixty days. Our studies showed that ApcMin mice exposed to B(a)P developed a significantly higher number (p< 0.05) of larger dysplastic adenomas compared to those exposed to B(a)P + olive oil. Treatment of mice with B(a)P and olive oil significantly altered (p< 0.05) the expression of drug metabolizing enzymes in both the colon and liver tissues. However, only GST activity was significantly higher (p< 0.05) in the liver of mice treated with 50 and 100 μg B(a)P/kg bw + olive oil. Lastly, olive oil promoted rapid detoxification of B(a)P by decreasing its organic metabolite concentrations and also decreasing the extent of DNA damage to colon and liver tissues (p< 0.05). These results suggest that olive oil has a protective effect against B(a)P-induced colon tumors.

Common γ chain (γC) cytokines, namely IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21 are important for the proliferation, differentiation, and survival of lymphocytes that display antitumor activity, thus stimulating considerable interest for the use of cytokines in cancer immunotherapy. In this review, we will focus on the γC cytokines that demonstrate the greatest potential for immunotherapy, IL-2, IL-7, IL-15, and IL-21. We will briefly cover their biological function, potential applications in cancer therapy, and update on their use in combinatorial immune strategies for eradicating tumors and hematopoietic malignancies.

Since metabolism is implicated in the carcinogenesis of toxicants, an efficient extraction method together with an analytical method is warranted to quantify tissue burdens of a carcinogen and/or its metabolites. Therefore, the aim of this study was to validate a pressurized liquid extraction (PLE) method for measuring metabolites of benzo(a)pyrene [B(a)P; a food-borne carcinogen] from tissue samples. The sample extraction was performed separately by PLE and liquid–liquid extraction (LLE). PLE followed by high-performance liquid chromatography coupled to online fluorescence detector (HPLC-FLD) was used to quantify separated analytes; and by ultra-high-performance liquid chromatography (UHPLC) coupled to atmospheric pressure chemical ionization tandem mass spectrometry (UHPLC-APCI-MS/MS) were used for confirmation purposes. The UHPLC-MS/MS was set-up in the atmospheric pressure chemical ionization (APCI) positive interface with selective reaction monitoring (SRM). The analytical performance characteristics of the PLE technique was assessed at different temperatures, pressure, number of cycles and solvent types. A methanol + chloroform + water mixture (30:15:10, v/v/v) yielded greater recoveries at an extraction temperature range of 60–80°C, pressure of 10 MPa and an extraction time of 10 min. The PLE method was validated by the analysis of spiked tissue samples and measuring recoveries and limits of quantitation for the analytes of interest using HPLC-FLD equipment. The optimized PLE-HPLC-FLD method was used to quantify the concentrations of B(a)P metabolites in liver samples obtained from a colon cancer animal model. Overall, PLE performed better in terms of extraction efficiency, recovery of B(a)P metabolites and shortened sample preparation time when compared with the classic LLE method.

The incidence of familial adenomatous polyposis (FAP) is one in 7,000 to 12,000 live births. Virtually, all surgically untreated patients with FAP inevitably develop colorectal-cancer in their lifetime because they carry the adenomatous polyposis coli gene. Thus prophylactic proctocolectomy is indicated. Surgical treatment of FAP is still controversial. There are however, four surgical options: ileorectal anastomosis, restorative proctocolectomy with ileal pouch-anal anastomosis, proctocolectomy with ileostomy, and proctocolectomy with continent-ileostomy. Conventional proctocolectomy options largely lie between colectomy with ileorectal anastomosis or ileal pouch-anal anastomosis. Detractors of ileal pouch-anal anastomosis prefer ileorectal anastomosis because of better functional results and quality of life. The functional outcome of total colectomy with ileorectal anastomosis is undoubtedly far superior to that of the ileoanal pouch; however, the risk for rectal cancer is increased by 30%. Even after mucosectomy, inadvertent small mucosal residual islands remain. These residual islands carry the potential for the development of subsequent malignancy. We reviewed the literature (1975-2012) on the incidence, nature, and possible etiology of subsequent ileal-pouch and anal transit zone adenocarcinoma after prophylactic surgery procedure for FAP. To date there are 24 studies reporting 92 pouch-related cancers; 15 case reports, 4 prospective and 5 retrospective studies. Twenty three of 92 cancers (25%) developed in the pouch mucosa and 69 (75%) in anal transit zone (ATZ). Current recommendation for pouch surveillance and treatment are presented. Data suggest lifetime surveillance of these patients.

The American Cancer Society estimates that 1,688,780 new cases of cancer will be diagnosed in 2017 and that 600,920 people will die from their disease. The burden of cancer is disproportionately borne by the poor and underserved. Underrepresented minority physician scientists and clinician researchers are uniquely qualified to address these disparities as they have frequently experienced them in their own families and communities. As some portion of health disparities is rooted in socioeconomic status and lesser education, economically deprived and first generation college students of all races and ethnicities also experience these disparities. Unfortunately, the number of physicians who do research has been declining so the need for programs that educate students in the art and science of research is increasing. The Meharry Medical College Summer Program in Integrative Science and Cancer Research (MMC-SPiISCR) has provided Meharry medical students with the opportunity to participate in short-term cancer research experiences for eleven years. The program is unique in combining weekly half-day workshops at MMC, an historically black college or university, with a research experience supported by faculty mentors at the Vanderbilt University School of Medicine (VUSM),an institution that includes the Vanderbilt Ingram Cancer Center, one of only 69 NCI-Designated Cancer Centers in the United States and District of Columbia. The workshops include topics emphasizing bioethics and responsible conduct of research as well as presentations by Meharry faculty on their cancer research, cancer disparities, cancer and big data and more. The overarching goal of this program is to inspire Meharry medical students to aspire to medical careers in academic medicine and/or careers that will ultimately include cancer research. To date, 73 MMC students have started and completed the program and 94% are from underrepresented minority groups. The male to female ratio reflects the male to female ratio of the class. Over half of the participants presented their work at meetings outside of the program including AACR National Meeting, AACR Science of Cancer Disparities, Society of Black Academic Surgeons, Student National Medical Association, American Medical Association Research Symposium, American Society for Clinical Oncology, KBRIN Bioinformatics Summit and the Meharry-Vanderbilt-TSU Cancer Partnership Annual Retreat. The students are authors on 27 manuscripts and these numbers are still growing as is the interest of program participants in doing a year of research. Surveys of both mentors and program participant mentees overwhelmingly support the strength of this program and participation in the future. This comprehensive program will go far towards fueling the physician-scientist pipeline with researchers whose life experiences mirror those of minority and underserved patients. Citation Format: Dana R. Marshall, Carol Freund-Taylor, Philip Lammers, Leon Dent, Samuel Adunyah, Billy Ballard. Meharry Medical College medical student summer program in integrative science and cancer research [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 5286.

Butyrate is a histone deacetylase inhibitor implicated in many studies as a potential therapy for various forms of cancer. High concentrations of butyrate (>1.5 mM) have been shown to activate apoptosis in several cancer cell lines including prostate, breast, and leukemia. Butyrate is also known to influence multiple signaling pathways that are mediators of cytokine production. The purpose of this study was to evaluate the impact of high concentrations of butyrate on the cancer microenvironment vis-à-vis apoptosis, cellular migration, and capacity to modulate cytokine expression in cancer cells. The results indicate that high concentrations of butyrate induced a 2-fold activation of caspase-3 and reduced cell viability by 60% in U937 leukemia cells. Within 24 hours, butyrate significantly decreased the levels of chemokines CCL2 and CCL5 in HL-60 and U937 cells, and decreased CCL5 in THP-1 leukemia cells. Differential effects were observed in treatments with valproic acid for CCL2 and CCL5 indicating butyrate-specificity. Many of the biological effects examined in this study are linked to activation of the AKT and MAPK signaling pathways; therefore, we investigated whether butyrate alters the levels of phosphorylated forms of these signaling proteins and how it correlated with the expression of chemokines. The results show that butyrate may partially regulate CCL5 production via p38 MAPK. The decrease in p-ERK1/2 and p-AKT levels correlated with the decrease in CCL2 production. These data suggest that while promoting apoptosis, butyrate has the potential to influence the cancer microenvironment by inducing differential expression of cytokines.

Objective. Although hydroxyurea (HU) has been used clinically to treat patients with sickle cell disease (SCD), not all patients benefit from HU treatment due to its toxicity. The objective of this study was to investigate the effectiveness of the use of two new Hb F-inducing nitrosourea analogues, 2-[3-(2-methyl, 2-nitroso) ureido]-2-deoxy-D-glucopyranose (MNGU) and 2-[3-(2-chloroethyl) ureido]-2-deoxy-D-glucopyranose (CGU), in combination with HU in K562 cells or erythroid progenitors. Materials and Methods. After K562 cells were cultured with different concentrations of HU with CGU or MNGU, aliquots of the cells were obtained to determine the total (benzidine-positive) hemoglobin level, number of F cells, and Hb F level. Erythroid progenitor cells of SCD patients and healthy donors were cultured with the optimal drug concentrations, and the number of BFU-E and Hb F level were determined. Results. Our results showed that the combined use of HU with CGU or MNGU increased the number of both benzidine-positive normoblasts and F cells in a synergistic manner. Further, a lower concentration of HU was required to induce a significant level of Hb F synthesis when combined with either of the two compounds in comparison with treatment with HU alone. On day 4, the number of benzidine-positive cells was 4.5- to 6.5-fold and the number of F cells was 5.0- to 8.0-fold higher than the respective numbers in the untreated K562 cells. Similarly, a 3.2- to 14.3-fold induction of Hb F was obtained when human erythroid progenitors from SCD patients were treated with the same drug combinations. Conclusion. Based on these results, the use of CGU or MNGU in combination with HU might offer substantial benefits to patients with SCD and other hemoglobinopathies.

Obesity has become a global epidemic and causes a chronic low-grade inflammation. This poses a large health burden because excess adiposity can lead to chronic diseases such as type 2 diabetes, cardiovascular disease and some cancers. Obese individuals get higher incidence, progression and mortality of cancers compared to lean ones. Particularly, breast cancer (BC) in women is closely associated with obesity. Despite an epidemiological link between obesity and low cancer survival rates, little is known about the molecular mechanisms by which obesity promotes BC progression. Obesity-derived chronic low-grade inflammation involves alteration of a chemokine network that may contribute to the cancer progression and metastasis. Herein, we proposed the novel concept that the chemokine network between obesity and BC builds an inflammatory burden via proinflammatory chemokines to promote cancer progression. We employed mesenchymal BC cell PY8119 and epithelial-like BC PY230 for triple negative BC (TNBC) cell model, and mouse 3T3-L1 preadipocyte and adipocyte conditioned media (CM) to mimic lean and obese conditions in vitro. We examined the profiles of chemokine signature of PY8119 and PY230 treated with preadipocytes and adipocytes CM using PCR array. Both preadipocytes and adipocytes CM-treated PY8119 and PY230 cells absent or low levels in chemokine receptors. On the other hand, the chemokines CCL2, 5, 7 and CXCL10 showed higher expression in both preadipocyte and adipocyte CM-treated PY8119. Interestingly, adipocyte CM-treated PY8119 cells dominantly expressed CXCL1-3 compared to preadipocyte CM-treated cells. In addition, CCL2, 5, 7, 20, and CXCL1, 5, 10 were highly expressed in both preadipocyte and adipocyte CM-treated PY230 cells. Moreover, CXCL2 and 3 were significantly induced in PY230 cells after treatment with adipocyte CM compared to preadipocyte CM. Taken together, the results indicate that dominant chemokines CXCL1-3 expressed in adipocyte CM-treated TNBC cells promote a pro-tumor inflammatory network. Hence, these proinflammatory microenvironment augmented by adipocytes might contribute to TNBC progression. Citation Format: Rosa Mistica Coles Ignacio, Hyeongjwa Choi, Carla Gibbs, Eunsook Lee, Samuel Adunyah, Deok-Soo Son. Involvement of proinflammatory chemokine network between adipocytes and triple negative breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 950. doi:10.1158/1538-7445.AM2017-950

Enhancer of zeste homolog 2 (EZH2) plays crucial roles on the development of cells and tissues as well as the progression of prostate cancer (PCa) and castration resistant prostate cancer (CRPC). EZH2 can upregulate and activate progenitor genes including androgen receptor (AR) and the target genes. However, the mechanisms by which EZH2 is regulated in PCa remain elusive. Literature reports that tumor necrosis factor (TNF) receptor associated factor 6 (TRAF6) is essential for both normal tissue development and regulation of oncogenic signaling pathways in cancers. In this study, we reported that EZH2 is regulated by PTEN and SKP2 network in PCa. Specifically, we showed that the aberrant upregulation of EZH2 and histone H3 lysine 27 trimethylation (H3K27me3) in both Pten null mouse embryonic fibroblasts (MEFs) in vitro and prostate tumors of Pten null mice in vivo, as compared to the controls. EZH2 levels were negatively correlated with TRAF6 in human PCa cells upon SKP2 dysregulation. Immunofluorescence (IF) staining results showed a co-localization of EZH2 and TRAF6 in nucleus of PC3 cells, and co-immunoprecipitation (co-IP) analysis further confirmed a physical binding of EZH2 and TRAF6 in PC3 cells. Ectopic expression of TRAF6 promoted the K63-linked polyubiquitination of EZH2 to decrease EZH2 and H3K27me3 levels in PCa cells. Conversely, TRAF6 knockdown resulted in a reduction of EZH2 polyubiquitination with an increase of EZH2 and H3K27me3 levels in PCa cells. Furthermore, the catalytically dead mutant TRAF6 C70A abolished the TRAF6-mediated polyubiquitination of human EZH2 in vivo in 293T cells and in vitro in the recombinant human EZH2 protein, as compared with TRAF6 WT. Together, we report for the first time a novel mechanism on EZH2 ubiquitination and an important signaling network of SKP2-TRAF6-EZH2-H3K27me3 in PCa cells. Our findings provide valuable clues on the mechanism and efficiency of targeting EZH2 in PCa and CRPC . Note: This abstract was not presented at the meeting. Citation Format: Wenfu Lu, Shenji Lu, Bo Li, Yingqiu Xie, Michael G. Izban, Billy R. Ballard, Sandeep A. Sathyanarayana, Samuel E. Adunyah, Robert J. Matusik, Zhenbang Chen. EZH2 regulation through lysine 63 linked ubiquitination in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5326. doi:10.1158/1538-7445.AM2017-5326

Breast cancer (BC) is the most frequent tumor in women worldwide. Although its mortality has significantly decreased owing to advanced therapies, triple negative breast cancer (TNBC) is still difficult to treat because of lack of estrogen receptor, progesterone receptor and HER-2. TNBC accounts for 12-24% of total BC and contributes to the aggressiveness and poorer outcomes. The risk of BC increases significantly in obese women. Obesity is also associated with the worse clinical prognosis of BC. But the underlying mechanisms between obesity and BC, particularly TNBC, remain unclear. Therefore, we compare the molecular mechanisms by which human adipocyte conditioned media (CM) affect TNBC cells (BT549) and non-TNBC cells (MCF7A). Adipocyte CM had no effect on the proliferation of both TNBC and non-TNBC cells. However, adipocyte CM enhanced significantly migration in TNBC cells compared to non-TNBC cells. Next, we examined the signaling pathway by which adipocyte CM promote migration of TNBC cell. AKT and ERK were activated in both TNBC cells and non-TNBC cells. However, phospho-STAT3 was significantly increased in TNBC cells. Also, N-cadherin, a marker for epithelial to mesenchymal transition (EMT), was increased at the late time point in TNBC cells. Furthermore, CXCR7 was specifically increased in TNBC cells after treatment with adipocyte CM using a PCR array. CXCR7 is chemoattractive to CXCL12 which is highly expressed in the lung, the bone marrow, and the liver, common sites of BC metastasis. Taken together, the results indicate that adipocyte CM may promote metastasis of TNBC cells through the CXCL12-CXCR7 axis by activating STAT3. Citation Format: Hyeongjwa Choi, Rosa Mistica C. Ignacio, Carla R. Gibbs, Eunsook Lee, Samuel E. Adunyah, Deok-Soo Son. Involvement of CXCL12-CXCR7 axis in adipocyte-induced TNBC metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2933. doi:10.1158/1538-7445.AM2017-2933

Interleukin-17 is a T-cell-derived pro-inflammatory cytokine, exhibiting multiple biological activities in a variety of cells and believed to fine tune all general phases of hematopoietic response. However, the signaling mechanism of this novel cytokine remains unknown. Here, we report for the first time that the early signaling events triggered by interleukin-17 involve tyrosine phosphorylation of several members of the JAK and STAT proteins in human U937 monocytic leukemia cells. Immunoprecipitation with specific antibodies followed by Western blot analysis with antiphosphotyrosine antibody has shown that in U937 cells, interleukin-17 induces time-dependent stimulation of tyrosine phosphorylation of JAK 1, 2 and 3, Tyk 2 and STAT 1, 2, 3 and 4 within 0.5 to 30 min. Interleukin-17-mediated tyrosine phosphorylation of these proteins strongly suggests that the JAK/STAT signaling pathway may play a major role in transducing signals from interleukin-17 receptors to the nucleus.

Interleukin-17 is a T cell derived pro-inflammatory cytokine exhibiting multiple biological activities in a variety of cells and believed to fine tune all general phases of hematopoietic response. However, the signaling mechanism of this novel cytokine remains unknown. The purpose of this study was to determine whether Interleukin-17 induces tyrosine phosphorylation of proteins and to find out whether the raf-1 kinase signaling pathway is involved in mediating its signaling. Using immunoblotting and immunocomplex kinase assays, we report that the early signaling events triggered by rhIL-17 involves rapid tyrosine phosphorylation of several cellular proteins including raf-1 within 0.5 to 30 min. Optimal stimulation of tyrosine phosphorylation was observed with 0.5 to 1.0 ng/ml of Interleukin-17. Further, Interleukin-17 stimulates rapid activation of raf-1 kinase. These findings provide the first evidence that the mechanism of IL-17 signaling involves rapid tyrosine phosphorylation and activation of raf-1 serine/threonine kinase.

Sodium butyrate (NaB) is an differentiation inducer currently under clinical investigation as a potential therapy for the treatment of sickle cell disease and prostate cancer. Though the biologic effects of this agent is well documented, its mechanism of action remains largely known. The mechanisms by which it transduces its signal to the nucleus is the subject of intense investigation in our laboratory. In this report, we demonstrate that NaB stimulates PKC activation by 3-fold and induces differential expression of several PKC isoforms. Notably, it upregulates PKC epsilon and downregulates PKC beta during erythroid differentiation. These findings suggest that certain PKC isoforms may play important roles in the signal transduction mechanisms of this agent leading to regulation of erythroid proliferation and differentiation.

Interleukin-11 (IL-11) is a pleiotropic cytokine which regulates the growth of hematopoietic progenitor cells and activates platelet maturation. Previous studies have shown that, IL-11 activates a set of signaling cascades involving the JAK/STAT and Raf/MAPK pathways. The purpose of the current studies was to obtain evidence about the possible involvement of PKC in the IL-11 signaling pathway. Evidence presented in this report suggests that IL-11 stimulates rapid PKC activation and markedly induces cytosolic to particulate (membrane) association of alpha and beta PKC isoforms. These findings provide preliminary evidence that PKC may be involved in the IL-11 signaling cascade.

Effects of Cu(2+), Ni(2+) or Cu(2+) + Ni(2+) on lipid peroxide and glutathione (GSH) levels in U937 cells were investigated. Cells were treated with 0, 5, 10, and 20 µM of Cu(2+) and/or Ni(2+) and H(2)O(2) (0.01 mM) and incubated for 24 hours at 37°C. Lipid peroxides were measured by the thiobarbituric acid assay (TBA). GSH intracellular levels were assayed by the GSH assay kit from EMD/Calbiochem (San Diego, California, USA). Cu(2+) or Ni(2+) significantly (P < 0.01) increased lipid peroxides in a dose-dependent manner, compared to controls. The effect was more pronounced for Cu(2+), compared to the Ni(2+)-treated samples. Cu(2+) + Ni(2+) increased lipid peroxides in a significant (P < 0.001), dose-dependent manner, compared to Cu(2+) or Ni(2+) alone (i.e., ratio of 2.5:1-fold for combined versus single treatments, respectively). Cu(2+) or Ni(2+) significantly decreased GSH levels in U937 cells, with the effect being pronounced for Cu(2+). Cu(2+) + Ni(2+) metal ions significantly (P < 0.001) depleted cells of GSH in a dose-dependent manner. Ethylene diamine tetraacetic acid (EDTA) at 50 or 100 µM moderately reduced the Cu(2+)- or Ni(2+)-induced effects on GSH levels. Interestingly, GSH levels generally decreased to half (except for the combined metal dose of 20 µM at 100 µM EDTA) of its level at the highest metal concentration tested for both the single or combined treatments. In conclusion, multiple exposures of cells to metal ions may be lethal to cells, compared to their single treatments.

Colorectal cancer (CRC), the most lethal long-term complication of inflammatory bowel disease (IBD), is the culmination of a complex sequence of molecular and histologic derangements of the colon epithelium that are initiated and at least partially sustained by prolonged chronic inflammation. Dysplasia, the earliest histologic manifestation of this process, plays an important role in cancer prevention by providing the first clinical alert that this sequence is under way and by serving as an endpoint in colonoscopic surveillance of patients at high risk for CRC. Restorative proctocolectomy (RPC) is indicated for patients with IBD, specifically for ulcerative colitis that is refractory to medical treatment, emergency conditions, and/or in case of neoplastic transformation. Even after RPC with mucosectomy, pouch-related carcinomas have recently been reported with increasing frequency since the first report in 1984. We review IBD-associated CRC and pouch-related neoplasia prevalence, adverse events, risk factors, and surveillances.Literature of IBD-associated CRC patients and those undergoing RPC surgeries through 2010 were prospectively reviewed.We found 12 studies from retrospective series and 15 case reports. To date, there are 43 reported cases of pouch-related cancers. Thirty-two patients had cancer in the anal transit zone (ATZ); of these, 28 patients had mucosectomy. Eleven patients had cancer found in the pouch body.RPC with mucosectomy does not necessarily eliminate risks. There is little evidence to support routine surveillance of pouch mucosa and the ATZ except for patients associated with histological type C changes, sclerosing cholangitis, and unremitting pouchitis.

Cytokines play an important role in the immune system, and abnormalities in their production have been found in many human diseases. Interleukin-21 (IL-21), a type I cytokine produced by activated T cells, has diverse effects on the immune system, but its ability to induce production of other cytokines is not well delineated. Furthermore, the signaling pathway underlying its action is poorly understood. Here, we have evaluated IL-21-induced cytokine production in human monocytes and U937 leukemia cells. We found that IL-21 induces upregulation of a variety of cytokines from multiple cytokine families. We also found that IL-21 triggers rapid activation of ERK1/2. Neutralizing antibody to the IL-21R prevented both IL-21-induced cytokine production and IL-21-induced activation of ERK1/2. Inhibition of ERK1/2 activity by the ERK-selective inhibitor U0126 reverses the ability of IL-21 to upregulate cytokine production, suggesting that IL-21-induced cytokine production is dependent on ERK1/2 activation.

Colorectal cancer ranks third in terms of mortalities in the United States. Consumption of Western Diet (rich in red meat and fats), contaminated with environmental toxicants such as benzo(a)pyrene [B(a)P] has also been implicated as one of the causative factors for sporadic colon cancer. Therefore, the objective of this study was to investigate the effect of dietary fat type on B(a)P -induced colon cancer in an adult male rat model, the Polyposis In the Rat Colon (PIRC) kindred type. Groups of PIRC rats (n = 5) were fed with AIN-76A regular diet (RD) or Western diet (WD) and these rats also received 25, 50 and 100 µg B(a)P/kg body wt., daily via oral gavage for a period of 60 days. Rats that were fed with the diets alone, but no B(a)P served as controls. Food consumption and body weights of the rats were periodically monitored. Subsequent to exposure, rats were sacrificed; colons, liver and other tissues were retrieved and preserved in 10% formalin for observation of gross pathological changes. Blood samples were collected and concentrations of cholesterol, triglycerides, and adiponectin were measured. Colon tissues were scored for tumors, and preserved in 10% formalin for observation of pathological changes. Colon and liver samples were analyzed for activation of drug metabolizing enzymes (DMEs) CYP1A1, CYP1B1 and GST. The lack of change in food consumption notwithstanding, body weight loss of WD group compared to RD group and controls (p < 0.05) was noticed. An increased incidence of adenomas and high grade dysplasia were encountered in rats that were fed with WD compared to RD and controls (p < 0.05). The colon tumor counts were more in B(a)P + WD rats compared to their B(a)P + RD counterparts, and also exhibited a B(a)P dose-response relationship, with 100 µg B(a)P/kg registering greater counts. Adenomas with high grade dysplasia were prominent in B(a)P + WD rats compared to B(a)P + RD rats. Immunohistochemical analyses of colon tissue samples for PCNA, cyclin D1, TGF-β, and β-catenin revealed increased levels of cell proliferation and nuclear positivity among all treatment groups. Rats that received B(a)P + WD showed increased levels of cholesterol and triglycerides in comparison to rats that received B(a)P + RD and also controls. Levels of adiponectin did not vary much between B(a)P + WD, and B(a)P + RD groups. Western diet consumption increased DME activation among rats that were given B(a)P + WD with marked increase in rats that were administered 100 µg/kg B(a)P + WD (p < 0.05) compared to other treatment groups. Our results demonstrate that WD accelerates the development of colon tumors induced by B(a)P through proinflammatory action, characterized by gain in tumor number and sizes, and body weight loss. Citation Format: Kelly L. Harris, Stephanie R. Pulliam, Mohammad S. Niaz, Mary K. Washington, Samuel E. Adunyah, Aramandla Ramesh. Western diet enhances benzo(a)pyrene [B(a)P]-induced colon tumorigenesis in the PIRC rat model via proinflammatory mechanisms. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1583. doi:10.1158/1538-7445.AM2014-1583

Sodium butyrate (NaB) is a sodium salt of butyric acid. It is a HDAC inhibitor implicated in many studies as a potential therapy for various forms of cancer. Due to its ability to promote total and gamma globin during erythroid differentiation, low concentrations (1.5 mM) have been shown to activate apoptosis in several cancer cell lines including prostate, endometrial, breast and leukemia. Low concentrations of NaB influence multiple signaling pathways that are known mediators of cytokine production. However, it is not known whether high concentrations alter these pathways having the capacity to modulate cytokine expression in cancer cells and alter the cancer microenvironment, which is the purpose of this study. We exposed U937 leukemia cells to NaB at 5 or 10 mM doses for various time points. The culture media of the cells were harvested and analyzed by Human Multi-Analyte Cytokine ELISArray for levels of chemokines and chemotactic properties via migration assay. As evidence of apoptosis, we monitored cells for caspase-3 activation and cell viability. Our results indicate NaB induces a 2-fold activation of caspase-3 but a decrease in cell viability by 60%. Also, NaB induces a significant decrease in levels of chemokines CCL2 and CCL5 in 24 hours. Moreover, monocyte migration towards culture media from NaB treated cells, decreased in time-dependent manner. To elucidate the signaling mechanism(s) used by NaB (5mM), we investigated whether NaB alters the phospho-protein levels of AKT, ERK1/2, p38 and JNK. We observed an increase in phosphorylation of p38 MAPK, but a decrease in ERK1/2 in response to NaB. Also, there was an initial decrease in p-AKT level within 2 minutes suggesting a decline of Akt activation. However, this was followed by re-activation of AKT by 24 hours post-treatment. Interestingly, NaB did not influence activation of JNK. This data suggests that while promoting apoptosis, NaB has the potential to influence cancer microenvironment by inducing differential expression of cytokines. While the mechanism by which NaB induces differential expression of cytokines remains unknown, potentially, it could occur via the AKT and/or MAPK mediated pathways. These effects may influence the biology of normal and cancer cells thereby altering the status of the patient receiving NaB therapy. *Pulliam is supported by NHLBI T32 Pre-doctoral training grant #2-T32-HL007735-16 to Dr. Adunyah and CTSA award #UL1TR000445 from the National Center for Advancing Translational Sciences. Additionally, Dr. Adunyah is supported by NCI Cancer Partnership U54 grant #5-U54-CA163069-02 and NIMHD MeTRC grant #8-U54-MD007593-04. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. Citation Format: Stephanie R. Pulliam, Roland Cooper, Samuel E. Adunyah. Sodium butyrate suppresses production of chemokines in human U937 cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 142. doi:10.1158/1538-7445.AM2014-142

Sporadic colon cancers have been shown to be triggered by diet and environmental factors. Epidemiological studies have shown that colon cancer rates were significantly reduced in Mediterranean countries where olive oil is the main ingredient of diet. Published works have shown that olive oil inhibits cell proliferation and promotes apoptosis in colorectal cancer cell lines. Studies conducted earlier in our laboratory have shown that dietary exposure to the environmental toxicant benzo(a)pyrene (BaP) leads to colon tumor formation. Benzo(a)pyrene biotransformation studies have shown that once BaP is metabolized by cytochrome P450 drug metabolizing enzymes, it forms metabolites such as BaP 7, 8-diol-epoxide (BPDE), BaP 3,6 & 6,12-diones. These metabolites have also been shown to cause double stranded breaks in DNA and cause oxidative damage. Therefore, we hypothesize that olive oil's interaction with BaP will modulate BaP metabolism and reduce colon tumor formation. In this study we investigated the effect of olive oil on BaP-induced colon carcinogenesis in male ApcMin mice. Mice were assigned to a control (n=7) or treatment group (n =7). Treatment consisted of 50 and 100 μg BaP/kg body weight dissolved in tricaprylin (BaP-only group) or olive oil administered daily via oral gavage for sixty days. Post exposure, mice were sacrificed; colon and liver tissues were retrieved from each group of mice and were preserved in formalin and pathological changes were evaluated. The tissues were further analyzed for the induction of drug metabolizing enzymes such as cytochrome 1A, cytochrome 1B1, and glutathione S-Transferase. Additionally, to determine if BaP caused oxidative DNA damage to tissues, genomic DNA was isolated from the respective tissues and we quantified aldehyde lesions. There was a reduced incidence of adenomas in colons of mice that ingested BaP + olive oil compared to mice that received BaP only (p < 0.05). CYP protein expression was reduced while GST protein expression increased in the colon and liver tissues of BaP + olive oil-treated mice compared to BaP only-treated mice. The BaP organic metabolite concentrations decreased, while aqueous metabolite concentrations increased in the BaP + olive oil group compared to BaP only-treatment group. DNA lesions were increased in the colon and liver tissues of BaP-treated mice compared to BaP + olive oil treated mice. In summary, our studies suggest that olive oil exerts a protective effect against BaP-induced colon cancer. Citation Format: Leah D. Banks, Priscilla Amoah, Mohammad S. Niaz, Mary K. Washington, Samuel E. Adunyah, Aramandla Ramesh. Olive oil alters benzo(a)pyrene biotransformation and reduces oxidative DNA damage in colon of ApcMin mouse. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1589. doi:10.1158/1538-7445.AM2014-1589