Lysosome-dependent FOXA1 ubiquitination contributes to luminal lineage of advanced prostate cancer

Changes in FOXA1 (forkhead box protein A1) protein levels are well associated with prostate cancer (PCa) progression. Unfortunately, direct targeting of FOXA1 in progressive PCa remains challenging due to variations in FOXA1 protein levels, increased FOXA1 mutations at different stages of PCa, and elusive post-translational FOXA1 regulating mechanisms. Here, we show that SKP2 (S-phase kinase-associated protein 2) catalyzes K6- and K29-linked polyubiquitination of FOXA1 for lysosomal-dependent degradation. Our data indicate increased SKP2:FOXA1 protein ratios in stage IV human PCa compared to stages I-III, together with a strong inverse correlation (r = -0.9659) between SKP2 and FOXA1 levels, suggesting that SKP2-FOXA1 protein interactions play a significant role in PCa progression. Prostate tumors of Pten/Trp53 mice displayed increased Skp2-Foxa1-Pcna signaling and colocalization, whereas disruption of the Skp2-Foxa1 interplay in Pten/Trp53/Skp2 triple-null mice demonstrated decreased Pcna levels and increased expression of Foxa1 and luminal positive cells. Treatment of xenograft mice with the SKP2 inhibitor SZL P1-41 decreased tumor proliferation, SKP2:FOXA1 ratios, and colocalization. Thus, our results highlight the significance of the SKP2-FOXA1 interplay on the luminal lineage in PCa and the potential of therapeutically targeting FOXA1 through SKP2 to improve PCa control.

MicroRNA-21 deficiency suppresses prostate cancer progression through downregulation of the IRS1-SREBP-1 signaling pathway

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.

Linking bacterial enterotoxins and alpha defensin 5 expansion in the Crohn's colitis: A new insight into the etiopathogenetic and differentiation triggers driving colonic inflammatory bowel disease

Evidence link bacterial enterotoxins to apparent crypt-cell like cells (CCLCs), and Alpha Defensin 5 (DEFA5) expansion in the colonic mucosa of Crohn's colitis disease (CC) patients. These areas of ectopic ileal metaplasia, positive for Paneth cell (PC) markers are consistent with diagnosis of CC. Retrospectively, we: 1. Identified 21 patients with indeterminate colitis (IC) between 2000-2007 and were reevaluation their final clinical diagnosis in 2014 after a followed-up for mean 8.7±3.7 (range, 4-14) years. Their initial biopsies were analyzed by DEFA5 bioassay. 2. Differentiated ulcer-associated cell lineage (UACL) analysis by immunohistochemistry (IHC) of the CC patients, stained for Mucin 6 (MUC6) and DEFA5. 3. Treated human immortalized colonic epithelial cells (NCM460) and colonoids with pure DEFA5 on the secretion of signatures after 24hr. The control colonoids were not treated. 4. Treated colonoids with/without enterotoxins for 14 days and the spent medium were collected and determined by quantitative expression of DEFA5, CCLCs and other biologic signatures. The experiments were repeated twice. Three statistical methods were used: (i) Univariate analysis; (ii) LASSO; and (iii) Elastic net. DEFA5 bioassay discriminated CC and ulcerative colitis (UC) in a cohort of IC patients with accuracy. A fit logistic model with group CC and UC as the outcome and the DEFA5 as independent variable differentiator with a positive predictive value of 96 percent. IHC staining of CC for MUC6 and DEFA5 stained in different locations indicating that DEFA5 is not co-expressed in UACL and is therefore NOT the genesis of CC, rather a secretagogue for specific signature(s) that underlie the distinct crypt pathobiology of CC. Notably, we observed expansion of signatures after DEFA5 treatment on NCM460 and colonoids cells expressed at different times, intervals, and intensity. These factors are key stem cell niche regulators leading to DEFA5 secreting CCLCs differentiation 'the colonic ectopy ileal metaplasia formation' conspicuously of pathogenic importance in CC.

Abstract PO-233: HPV+ and HPV- HNSCC show similar nrf2 nuclear and cytoplasmic staining patterns

This study set out to observe and better understand the differences, if any, in staining patterns for the oxidative stress response transcription factor Nrf2 in HNSCC patients who were HPV+ non- tobacco and alcohol users vs. HPV- tobacco and alcohol users. Increased Nrf2 activity is associated with resistance to therapy and poor outcomes. Tissues samples were obtained from the head and neck cancer repository of Nashville General Hospital at Meharry and Meharry Medical College. Nashville General Hospital at Meharry is a safety net hospital that serves the under- and uninsured citizens of Davidson County TN. FFPE sections were stained with anti- human Nrf2 antibody (Abcam 31163) and scored using a semi-quantitative evaluation gradient scale from 0-3 with 0 indicating no stain and 3 indicating strong positive Nrf2 staining. This study made use of 5 HPV+ and 2 HPV- patients. The results show that all HNSCC in the HPV+ and HPV- samples revealed positive staining for Nrf2 that ranged from weak to intense. We observed that the poorly differentiated HNSCC had a strong positive nuclear stain for Nrf2 when compared to lower tumor grades. Irrespective of whether the patient was in the HPV+ nonsmoker-nondrinker or HPV- smoker-drinker group, histological data indicates there was a positive correlation between increased Nrf2 staining and worsening tumor grade. These preliminary data suggest that potential use of Nrf2 as a prognostic biomarker for HNSCC will need to be evaluated differently for HPV+ and HPV- tumors, as HPV+ tumors are generally more responsive to therapy. Developing therapy that specifically targets Nrf2 could potentially play an immense role in managing HNSCC. Some of the limitations encountered in this study includes limited sample size.

Citation Format: Oladipupo O. Anibire, Oyinloye Jose, Kenyada Williams, Billy R. Ballard, Michael G. Izban, Dana Marshall. HPV+ and HPV- HNSCC show similar nrf2 nuclear and cytoplasmic staining patterns [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-233.

KDM5B Is Essential for the Hyperactivation of PI3K/AKT Signaling in Prostate Tumorigenesis

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.

Abstract 1177: Insurance status and racial disparities in mortality for black and white head and neck cancer patients in the United States

Historically, and currently, black males have the highest mortality rates of any demographic group defined by race plus gender. Even though incidence has dropped for all demographic groups, and survival has improved as well, black males still bare a disproportionate burden of mortality. It has been reported that even when controlling for variables associated with prognosis, including socioeconomic status, black males still die at higher rates than white males. The question is whether this is true when one focuses on patients in lower socioeconomic groups where baseline health is poor for both blacks and whites. We hypothesized that patients in the lowest socioeconomic tertile would have a life expectancy that was significantly reduced compared to those of higher socioeconomic tertiles regardless of race, tumor grade, age at diagnosis, insurance status, anatomic subsite of the cancer and HPV status (all factors associated with prognosis). Towards answering this question, we analyzed de-identified data from a customized head and neck cancer dataset with HPV status, additional cancer treatment fields and census tract SES subset recode, from the Surveillance, Epidemiology and End Results (SEER) database that tracked patients diagnosed with HNSCC from 2010-2016. This retrospective cohort multivariate analysis utilized survival analysis methods such as Kaplan-Meier survival, hazard curves, regression, and the hypertabastic survival method, to analyze the survival time of our patients. Cross-tabulation between the registry SES tertile and race shows significance (p<0.001) with the majority of blacks (58%) in the lowest socioeconomic tertile compared to 21.9% of whites. Blacks significantly differ from whites for categories age at diagnosis (p<4.8E-16), subsite hypopharynx (p<2.6E-4), subsite oropharynx (p<1.5E-7), subsite tongue (p<4.5E-4), HPV status (p<3.4E-28), and presence in uninsured insurance category (p<4.2E-7). Individuals in the lowest SES tertile and the uninsured groups died at higher rates than their wealthier insured peers. Proportional hazards regression reveals that across all insurance groups (Insured, Uninsured, Medicaid, and Unknown), blacks had significantly shorter survival than whites. So, regardless of whether we used SES tertile rank or insurance status as proxies for SES, and despite the idea that low SES would level the mortality playing field for black and white HNSCC patients, this preliminary analysis showed otherwise. Additionally, the association of black race with additional variables associated with poor prognosis continues to confound the interpretation of these outcomes. Determining that the racial mortality disparity exists regardless of socioeconomic tertile or insurance status can guide future research to focus on biological factors that may impact survival outcome.

Citation Format: Dana R. Marshall, Joycemary Amponsem, Billy R. Ballard, Mohammed A. El Kadmiri, Young J. Kim, Derek Wilus, Mohammad A. Tabatabai. Insurance status and racial disparities in mortality for black and white head and neck cancer patients in the United States [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1177.

The MYTHS of De novo Crohn's Disease After Restorative Proctocolectomy with Ileal Pouch-anal Anastomosis for Ulcerative Colitis

Background

1.1.Inflammatory Bowel Disease (IBD) are the manifestation of overzealous dys-regulated immune response in the intestinal tract, directed primarily against the indigenous microbes combined with defective functioning of anti-inflammatory pathways. Finding a trustable lead to predicting de novo Crohn's Disease (CD) prior to performing "pouch surgery", Restorative Proctocolectomy (RPC) with Ileal Pouch-Anal Anastomosis (IPAA) for UC and/or Indeterminate Colitis (IC) is clinically important and remains debatable. De novo CD is a subsequent long-term postoperative complication in IBD patients with Ulcerative Colitis (UC) undergoing IPAA. Herewith we discuss this understanding in laboratory-based basic science research, with its molecular application as a possible corner stone tool for clinical progress and success in the IBD Clinic. Crypt Paneth cell (PCs) secreted enteroendocrine alpha-defensin 5 (DEFA5)" if developed properly is likely to solve diagnostic and prognostic difficulty in IBD Clinics. DEFA5 has shown the ability to differentiate the predominant subtypes of colonic IBD (CC vs. UC) at first endoscopy biopsy, avoiding diagnosis delay prior to colectomy. In addition, DEFA5 accurately circumvents indeterminate colitis (IC) patients into accurate IBD subtype (UC or CC). Further, DEFA5 can be used in selecting CC patients that may have positive outcomes after IPAA surgery [1]. Furthermore, likewise, DEFA5 can predict UC patients likely to have positive or poor outcome, e.g. those patients that are likely to transform/ convert and adhere to de novo Crohn's after IPAA can be picked up in endoscopy biopsy before surgery.

Aim

1.2.To assessed comprehensive state-of-the-art understanding domains on the de novo Crohn's disease subsequent to IPAA surgery for ulcerative colitis.

Methods

1.3.A literature search based on preferred reporting items for over-review and meta-analysis protocols (PRISMA-P) was performed. A comprehensive current search of PubMed, MEDLINE, CINAHL, Embase, Google® search engine and Cochrane Database of collected reviews was performed from January 1990 through December 2018. The search consists of retrospective studies and case reports of reporting postoperative de novo CD incidence and adverse events. Secondary and hand/manual searches of reference lists, other studies cross-indexed by authors, reviews, commentaries, books and meeting abstracts were also performed. Studies were included only if the diagnosis of de novo CD was established clinically and histologically based on inflammation of afferent limb(s) or perianal disease. The search excluded non-English language and non-human studies as well as editorials.

Results

1.4.Published data on de novo CD developing after RPC with IPAA are still limited. A total of three hundred and sixty-five (#365) patients in 13 publications reported de novo CD after a median follow-up of 66 (range: 3-236) months. All patients were diagnosed with clinically active pouch CD during follow-up surveillance after IPAA for UC or IC. A de novo CD diagnosis depended on either inflammation in the mucosa involving the small intestine proximal to the ileal pouch any time after IPAA surgery and/or when perianal complications developed after closure of a temporary diverting loop ileostomy. Successful management is facilitated by co-operation within a multidisciplinary team of gastroenterologists and colorectal surgeons and closely involving the patient in therapeutic decisions. Awareness of symptoms leads to timely consultation, diagnosis, treatment and restoration of intestinal continuity.

Conclusion

1.5.The nature history and risk of de novo CD after IPAA for UC remains debatable. Chronic pouchitis and/or pouch failure often precedes a diagnosis of de novo CD. A successful management is facilitated by a triad cooperation between gastroenterologists, colorectal surgeons and the patient.

Inflammatory Bowel Disease On-Line Web-Based Guide to Health Professionals and Patients in Developing and African Nations

Introduction

1.1.Inflammatory Bowel Disease (IBD) is recklessly evolving worldwide as incautious disaster, especially in developing nations as a regional duplicitous emergence disease. It has come to light that adaptive Western culture, rapid urbanization lifestyle in the developing nations has been seen to be associated with this increasing trend incidence. Apparent unclassified strategic challenge assessment of how key trends and uncertainties might lead the world over the next decades to help developing nations and plan for the long term. Healthcare professionals are faced with limited resource and unequipped laboratories for IBD diagnostics, prognostics and monitoring management. Limited knowledge on IBD among developing nation's physician's/healthcare providers is painstaking and indisputable challenge. With the emergence of advanced communications technology, the internet offers diverse, substantial, easily accessible, and educational resources that are more time- and cost-efficient than conventional modes of knowledge acquisition. An On-Line Web-Based Resources about IBD, as a guide would greatly assist health professionals and patients.

Methods

1.2.We performed a literature search according to PRISMA-P (preferred reporting items for review and meta-analysis and searches in PubMed (MEDLINE database) to identify and select peer-reviewed articles allied to web-based educational accoutrements for IBD.

Results

1.3.In developing nations, locally trained physicians have limited knowledge on IBD. Mostly, IBD is not included in their training Core Curriculum and research in this field/area is limited in these countries. The healthcare approaches, both at the primary care and referral levels, many times lack the essential regular clinical guidance and laboratory evaluation assessments needs for monitoring patients. Moreover, increasing treatment costs impose additional burden on the healthcare systems. Expensive pharmacological biosimilar and biologic agents/drugs, new treatment targets, and new quality indicators in patient health quality of life and care are significant challenge in addition to early manifestations of IBD are likely to be missed at most health institutions.

Conclusion

1.4.We herewith summarize an on-line web-based e-learning guide for IBD-related educational resources to assist physicians, healthcare personnel and patients worldwide, especially in the developing nations where the epidemiological monitoring studies are limited, due to a lack of medical surveillance systems and reliable and unified registries and databases.

Correction: Human alpha defensin 5 is a candidate biomarker to delineate inflammatory bowel disease

[This corrects the article DOI: 10.1371/journal.pone.0179710.].

Abstract 5326: EZH2 regulation through lysine 63 linked ubiquitination in prostate cancer

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

Human alpha defensin 5 is a candidate biomarker to delineate inflammatory bowel disease

Inability to distinguish Crohn's colitis from ulcerative colitis leads to the diagnosis of indeterminate colitis. This greatly effects medical and surgical care of the patient because treatments for the two diseases vary. Approximately 30 percent of inflammatory bowel disease patients cannot be accurately diagnosed, increasing their risk of inappropriate treatment. We sought to determine whether transcriptomic patterns could be used to develop diagnostic biomarker(s) to delineate inflammatory bowel disease more accurately. Four patients groups were assessed via whole-transcriptome microarray, qPCR, Western blot, and immunohistochemistry for differential expression of Human α-Defensin-5. In addition, immunohistochemistry for Paneth cells and Lysozyme, a Paneth cell marker, was also performed. Aberrant expression of Human α-Defensin-5 levels using transcript, Western blot, and immunohistochemistry staining levels was significantly upregulated in Crohn's colitis, p< 0.0001. Among patients with indeterminate colitis, Human α-Defensin-5 is a reliable differentiator with a positive predictive value of 96 percent. We also observed abundant ectopic crypt Paneth cells in all colectomy tissue samples of Crohn's colitis patients. In a retrospective study, we show that Human α-Defensin-5 could be used in indeterminate colitis patients to determine if they have either ulcerative colitis (low levels of Human α-Defensin-5) or Crohn's colitis (high levels of Human α-Defensin-5). Twenty of 67 patients (30 percent) who underwent restorative proctocolectomy for definitive ulcerative colitis were clinically changed to de novo Crohn's disease. These patients were profiled by Human α-Defensin-5 immunohistochemistry. All patients tested strongly positive. In addition, we observed by both hematoxylin and eosin and Lysozyme staining, a large number of ectopic Paneth cells in the colonic crypt of Crohn's colitis patient samples. Our experiments are the first to show that Human α-Defensin-5 is a potential candidate biomarker to molecularly differentiate Crohn's colitis from ulcerative colitis, to our knowledge. These data give us both a potential diagnostic marker in Human α-Defensin-5 and insight to develop future mechanistic studies to better understand crypt biology in Crohn's colitis.

SKP2 loss destabilizes EZH2 by promoting TRAF6-mediated ubiquitination to suppress prostate cancer

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.

Protection Against Dimethylbenz[a] Anthracene-Induced Breast Cancer in Female Rats by α-Lactalbumin

Consumption of α-lactalbumin as dietary protein offers a beneficial effect on breast cancer development. Breast cancer was developed by gavage administration of single dose of dimethylbenz(a)anthracene (DMBA) in female rats, maintained on AIN-76A diet with either 20% casein or α-lactalbumin (a component of whey protein). All tumors were detected by palpation. After approximately 130 days of DMBA administration, the animals were euthanized. There was a delay in the development of breast tumor in the α-lactalbumin group in comparison to the casein group. The number of tumors per rat was less in the α-lactalbumin group than that in the casein group at any time point up to 130 days after DMBA administration. Also the incidence of tumors and tumor volume was less in the α-lactalbumin group than those in the casein group. The casein group had a mixture of grade I, grade II and grade III tumors whereas the α-lactalbumin group had mostly grade I tumor. Furthermore, the proliferative index was significantly lower in the α-lactalbumin group than that in the casein group.

SKP2 inactivation suppresses prostate tumorigenesis by mediating JARID1B ubiquitination

Aberrant elevation of JARID1B and histone H3 lysine 4 trimethylation (H3K4me3) is frequently observed in many diseases including prostate cancer (PCa), yet the mechanisms on the regulation of JARID1B and H3K4me3 through epigenetic alterations still remain poorly understood. Here we report that Skp2 modulates JARID1B and H3K4me3 levels in vitro in cultured cells and in vivo in mouse models. We demonstrated that Skp2 inactivation decreased H3K4me3 levels, along with a reduction of cell growth, cell migration and malignant transformation of Pten/Trp53 double null MEFs, and further restrained prostate tumorigenesis of Pten/Trp53 mutant mice. Mechanistically, Skp2 decreased the K63-linked ubiquitination of JARID1B by E3 ubiquitin ligase TRAF6, thus decreasing JARID1B demethylase activity and in turn increasing H3K4me3. In agreement, Skp2 deficiency resulted in an increase of JARID1B ubiquitination and in turn a reduction of H3K4me3, and induced senescence through JARID1B accumulation in nucleoli of PCa cells and prostate tumors of mice. Furthermore, we showed that the elevations of Skp2 and H3K4me3 contributed to castration-resistant prostate cancer (CRPC) in mice, and were positively correlated in human PCa specimens. Taken together, our findings reveal a novel network of SKP2-JARID1B, and targeting SKP2 and JARID1B may be a potential strategy for PCa control.

Abstract 90: K63-linked JARID1B ubiquitination by TRAF6 contributes to aberrant elevation of JARID1B in prostate cancer

Aberrant elevation of JARID1B and histone H3 Lys4 trimethylations (H3K4me3) is frequently observed in many diseases including prostate cancer (PCa), yet the mechanisms on the regulations of JARID1B and H3K4me3 through epigenetic modifications still remain poorly understood. In this study we performed immunohistochemistry staining, immunofluorescence imaging, immunoprecipitation, shRNA and Western blotting analysis in mouse embryonic fibroblasts (MEFs), mouse models, and cultured human prostate cancer cells. As a result, we discovered that SKP2 modulates JARID1B and H3K4me3 levels in vitro in PTEN null prostate cancer cells and in vivo in Pten/Trp53 mouse models. We demonstrated that levels of SKP2, JARID1B and H3K4me3 are strikingly elevated in vitro and in vivo when both PTEN and P53 are inactivated. Importantly, SKP2 inactivation resulted in a reduction of cell growth, cell migration and malignant transformation of Pten/Trp53 double null MEFs, and further restrained prostate tumorigenesis of Pten/Trp53 mutant mice. Mechanistically, JARID1B is ubiquitinated by E3 ligase TRAF6 through the K63-linkage in prostate cancer cells. Interestingly, SKP2 contributes to JARID1B ubiquitination machinery as a non-E3 ligase regulator by decreasing TRAF6-mediated ubiquitination of JARID1B. SKP2 deficiency resulted in an increase of JARID1B ubiquitination and in turn a reduction of H3K4me3, and induced senescence through JARID1B accumulation in nucleoli of PCa cells and prostate tumors of mice. Furthermore, we showed that the aberrant levels of SKP2, JARID1B, and H3K4me3 are associated with malignant features of castration-resistant prostate cancer (CRPC) in mice. Overall, our findings reveal a novel network of SKP2- JARID1B, and targeting SKP2 and JARID1B may be a potential strategy for PCa control.

Citation Format: Wenfu Lu, Shenji Liu, Bo Li, Yingqiu Xie, Christine Adhiambo, Qing Yang, Billy R. Ballard, Keiichi I. Nakayama, Robert J. Matusik, Zhenbang Chen. K63-linked JARID1B ubiquitination by TRAF6 contributes to aberrant elevation of JARID1B in prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 90. doi:10.1158/1538-7445.AM2015-90

Structural mass spectrometry of tissue extracts to distinguish cancerous and non-cancerous breast diseases

Aberrant metabolism in breast cancer tumors has been widely studied by both targeted and untargeted analyses to characterize the affected metabolic pathways. In this work, we utilize ultra-performance liquid chromatography (UPLC) in tandem with ion mobility-mass spectrometry (IM-MS), which provides chromatographic, structural, and mass information, to characterize the aberrant metabolism associated with breast diseases such as cancer. In a double-blind analysis of matched control (n = 3) and disease tissues (n = 3), samples were homogenized, polar metabolites were extracted, and the extracts were characterized by UPLC-IM-MS/MS. Principle component analysis revealed a strong separation between disease tissues, with one diseased tissue clustering with the control tissues along PC1 and two others separated along PC2. Using post-ion mobility MS/MS spectra acquired by data-independent acquisition, the features giving rise to the observed grouping were determined to be biomolecules associated with aggressive breast cancer tumors, including glutathione, oxidized glutathione, thymosins β4 and β10, and choline-containing species. Pathology reports revealed the outlier of the disease tissues to be a benign fibroadenoma, whereas the other disease tissues represented highly metabolic benign and aggressive tumors. This IM-MS-based workflow bridges the transition from untargeted metabolomic profiling to tentative identifications of key descriptive molecular features using data acquired in one analysis, with additional experiments performed only for validation. The ability to resolve cancerous and non-cancerous tissues at the biomolecular level demonstrates UPLC-IM-MS/MS as a robust and sensitive platform for metabolomic profiling of tissues.

Knockdown of aberrantly upregulated aryl hydrocarbon receptor reduces tumor growth and metastasis of MDA-MB-231 human breast cancer cell line

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that belongs to the basic-helix-loop-helix (bHLH)-Per-ARNT-Sim (PAS) superfamily of transcription factors, mediates toxic response induced by environmental chemicals such as polycyclic aromatic hydrocarbons (PAH). AhR is expressed at high levels in several human breast carcinoma cell lines in direct correlation with the degree of their malignancy. Recent studies suggest a possible role for AhR in cancer independent of PAH. Therefore, we established stable AhR knockdown cells of the human breast cancer cell line MDA-MB-231 and analyzed their tumorigenic properties in in vitro and in vivo model systems. In addition we analyzed their response to radiation and chemotherapeutic treatment. AhR knockdown attenuated these cells tumorigenic properties in vitro including proliferation, anchorage independent growth, migration and apoptosis and reduced orthotopic xenograft tumor growth and lung metastasis in vivo. Notably, we observed that AhR knockdown enhanced radiation-induced apoptosis as well as significantly decreased cell clonogenic survival. Furthermore, AhR knockdown in MDA-MB-231 cells sensitized them to paclitaxel treatment, evident by a decrease in the required cytotoxic dose. Subsequent analysis revealed AhR knockdown significantly reduced phosphorylation of AKT, which impacts cell proliferation and survival. Apoptosis-focused gene expression analyses revealed an altered expression of genes regulating apoptosis in MDA-MB-231 cells. Collectively, our data identify AhR as a potential novel therapeutic target in the treatment of metastatic breast cancer.

Abstract 3710: Targeted inhibition of arginase-1 may underline the suppression of the development of colonic neoplasia in a transgenic APC Min mouse model

Colorectal cancer (CRC) is the third-leading malignancy in the United States. This year alone, about 141,210 new cases of colorectal cancer will be diagnosed and more than 49,380 people will die from the disease. Strategies have focused on early screening practices and the prevention of the development of colonic adenomas that serve as precursors of invasive colon cancers. We have recently showed that chloroquine (CQ) an anti-malarial and anti-rheumatoid agent has the capacity to competitively inhibit intracellular arginase-1 (ARG-1) and that this inhibition increases the nuclear localization of the cell cycle regulator p53 protein in colon cancer cell lines. However, the mechanism of CQ-induced inhibition of ARG-1 that results in the up-regulation of p53 is unclear. The goal of the current study was to examine the chemopreventive efficacy of CQ in the development of colonic neoplasia and to further evaluate the possible mechanism(s) of action. In this regard, six weeks old Apc(Min/+) mice were treated daily (except Saturdays and Sundays) with 0-50 mg CQ/kg body wt. via oral gavage for forty days. Post-treatment, mice were sacrificed and jejunum and colon were retrieved and preserved in 10% formalin for observation of any gross pathological changes. The results of this study showed an increased in prevalence of colonic adenomas in untreated mice compared with treated mice (&lt; 0.05). Interestingly, histochemical analysis showed significant numbers of adenomas with high-grade dysplasia (as evidenced by the presence of increased fibrous tissue core) in untreated control mice in comparison with drug-treated mice (&lt;0.05).Since emerging studies have identified the overexpression of ARG-1 in a variety of human malignancies, including cancer of the colon, we then investigated the impact of CQ on ARG-1 levels. To this end, HT-29 cells were co-incubated with CQ (0-50 μM) for 24 h and the levels of ARG-1 were determined by western blot assay. Surprisingly, our result showed that CQ-induced inhibition of ARG-1 level corresponded to the diminution of β-catenin protein via to its phosphorylation. Further immuno- fluorescence analysis showed an increased level of nuclear localization of GFP tagged p53 (GFP-p53) and p21 in transiently transfected HT-29 cells upon CQ treatment. The observation that targeting ARG-1 results in a corresponding decrease in β-catenin level is intriguing, since the Wnt/β-catenin signaling is fundamental to colon carcinogenesis and spontaneous tumorigenesis in Apc(Min/+) mice and patients with familial adenomatous polyposis.In conclusion, our cumulative findings indicate that CQ ameliorates the development of colonic neoplasia and that the inhibition of ARG-1 and β-catenin may contribute to its chemopreventive effects in intestinal tumorigenesis.

Citation Format: Efe W. Iyamu, Mohammad S. Niaz, Aramandla Ramesh, Amos Sakwe, Kieosha Williams, Billy R. Ballard, Samuel E. Adunyah. Targeted inhibition of arginase-1 may underline the suppression of the development of colonic neoplasia in a transgenic APC Min mouse model. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3710. doi:10.1158/1538-7445.AM2013-3710

Adenocarcinomas After Prophylactic Surgery For Familial Adenomatous Polyposis

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.

Abstract B71: Potential role of hemoglobin in colorectal cancer initiation in inflammatory bowel disease setting

Background: Inflammatory bowel disease (IBD) is a recognized high risk condition to develop colorectal cancer (CRC) and other intestinal cancers. Several risk factors have been described, allowing preventive strategies to focus on these patients: extensive long-standing disease, severity of inflammation, family history of CRC and primary sclerosing cholangitis (PSC).

Aims: While using MALDI MS tissue profiling, we found a unique spectral peak at mass-to-charge ratio (m/z) 5045 to be more intense in inflamed colon samples from IBD patients compared to adjacent normal tissue and/ or diverticulosis (DV). We investigated this signal as a possible transforming factor in CRC initiation, in the setting of IBD.

Methods: We profiled colonic mucosal and submucosal layers of 99 IBD patients for biomarkers that differentiated ulcerative colitis (UC) from Crohn's colitis (CC). We determined these unique differentiating proteins by histology-directed proteomic profiling using MALDI MS; protein identification utilized LC/MS/MS. We tested DNA damage by exposing an identified protein to a normal colonic epithelial cell-line (NCM 356). DNA damage was tested by comet assay.

Results: LC-MS/MS identified m/z 5045 in CC/UC subjects as triply charged free hemoglobin ion chain (Hb). Validation studies used protein extracts and tissues from full thickness samples from UC, CC, and diverticulosis (DV, controls) subjects. Both CC and UC mucosal and submucosal samples were strongly positive for Hb-α. However, DV staining was restricted to erythrocytes found in submucosal capillaries. There was no significant difference in Hb-α level between UC and CC; however UC and CC levels were significantly higher than those in DV samples (p&lt; 0.006 and p&lt; 0.0001, respectively). When normal colonocytes (1x105 cells/ml) were exposed to Hb (300μM for 4 hours), there was clear DNA damage analyzed by comet assay. We noted macrophage erythrophagocytosis of extravasated erythrocytes.

Conclusion: Free Hb was found in UC/CC but not DV mucosa/submucosa tissue. Free Hb resulted from extravasated macrophage erythrophagocytosis. Hb significantly induced DNA-damage of normal epithelial colonocytes (NCM356). DNA-damage could potentially increase risks for CRC transformation. Further elucidative studies are underway.

Citation Format: Laura A. Franklin, Joan C. Smith, Billy R. Ballard, Erin H. Seeley, Mary K. Washington, Jeremy L. Norris, Kevin L. Schey, Harold L. Moses, Richard M. Caprioli, Samuel E. Adunyah, Amosy E. M'Koma. Potential role of hemoglobin in colorectal cancer initiation in inflammatory bowel disease setting. [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr B71.

Abstract B68: Colorectal Cancer in the Setting of Inflammatory Bowel Disease: Role of Hemoglobin

Colorectal carcinoma (CRC) is a serious complication of inflammatory bowel disease (IBD) and accounts for approximately 15% of all IBD-associated deaths. The likelihood of IBD-related carcinoma is greater than that of sporadic CRC. Over one half are diagnosed at stage III or IV when cancer cells have already invaded surrounding tissues and most conventional therapeutics are limited in their success. Therefore the early detection of cancer, which is difficult in IBD, is crucial for its ultimate control and prevention. While mining the colonic mucosal and submucosal layers for biomarkers that differentiate ulcerative colitis (UC) from Crohn's colitis (CC) using Matrix-assisted laser desorption/ionization (MALDI) profiling, we found a signal at m/z 5045 to be more intense in UC. Liquid chromatography–mass spectrometry (LC-MS/MS) analysis allowed identification of this signal as triply charged hemoglobin alpha chain.

Macrophages are highly versatile phagocytes active in multiple roles in the immune system and key players in the inflammatory response. Their presence within the inflammatory microenvironment, in some cases, has been proven to increase transformation, angiogenesis, and immunosuppression. In hemorrhagic situations (as in UC), macrophages engulf erythrocytes that are outside the vascular bed and as a result free hemoglobin is released. Hemoglobin induces DNA damage in human colonic cells and is genotoxic. The potential carcinogenic effects of hemoglobin were documented when it was shown that hemoglobin increases the number of aberrant crypt foci in colon mucosa. In the colon, free hemoglobin is expected to increase the production of reactive oxygen (O2) species (ROS) from peroxides via the Fenton reaction, which may be the cause of cellular toxicity and eventually pro-mutagenic lesions. Intracellular reactions with active O2 can result in the initiation and progression of carcinogenesis by induction of gene mutations, chromosomal damage and cytotoxic effects.

We hypothesize that elevated expression of mucosal free hemoglobin would be associated with an increased risk of CRC. To validate this hypothesis will require investigating whether hemoglobin could be classified as a proliferative or transforming agent for colon cancer cells by causing reactive oxygen species release and subsequent DNA damage. For this purpose, we will assess the cellular viability of normal colonic cell-lines, NCM 356 and NCM 460. These cell-lines will be treated with hemoglobin at different concentrations to determine the changes in levels of ROS. ROS production will be measured using C-400 staining assay and further analysis will be carried out using FACS. Additionally, we will also examine the potential cytotoxicity of hemoglobin.

Supported: MMC-VICC Cancer Partnership Grant#: 3U54CA091408-09S 1; MeTRC grant#: 5U54RR026140-03, and Vanderbilt SPORE in GI Cancer Grant#: P50CA095103.

Abstract 698: Overexpression of the aryl hydrocarbon receptor correlates with high tumor grade in human breast invasive carcinomas

The aryl hydrocarbon receptor (AhR) is a ligand-activated basic helix-loop-helix transcription factor which binds environmental poly aromatic hydrocarbons (PAH) and mediates their carcinogenic effects. Recent reports, including data from our laboratory implicate AhR in breast cancer development and progression independent of the receptor occupancy by PAH. In this study we investigated the potential of AhR as a stage specific marker of breast cancer. We examined the expression of AhR by immunohistochemistry in tissue microarrays (TMA) containing 192 specimens of clinically defined three stages of invasive breast cancer: node-negative (NN), node-positive (NP) and metastatic (Met) carcinoma. The TMA were obtained from the National Cancer Institute Cooperative Breast Cancer Tissue Resource [NCI-CBCTR] and were stained for AhR using high affinity antibody. The AhR staining was then scored by three evaluators, including two pathologists who were blinded to the study. Statistical analysis showed a significant correlation between the AhR expression and the carcinoma case type (NN, NP or Met) (p-value of ANOVA is &lt; 0.0003), and although there is a significant difference of AhR expression among carcinoma case type of white women (p&lt; 0.0017) there is no significant difference for black women (p&lt;0.0968). There is also a strong positive correlation between the receptor expression and the tumor grade (p &lt;0.0001). While there is no correlation with the status of estrogen or progesterone receptors (p= 0.1643 and 0.1884, respectively), there is strong correlation of high AhR expression and invasive breast carcinoma in women over 50 years old (p&lt;0.0043). In conclusion, our findings identify the AhR as a new predictive clinical marker for metastatic breast cancer and a unique target for the design of novel selective inhibitors for therapeutic intervention of metastatic breast cancer. More importantly, the AhR overexpression identifies a subset of patients who could benefit from therapy targeting this receptor.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 698. doi:1538-7445.AM2012-698

Abstract 2058: Colorectal cancer in the setting of inflammatory bowel disease: role of hemoglobin

Colorectal carcinoma (CRC) is a serious complication of inflammatory bowel disease (IBD) and accounts for approximately 15% of all IBD-associated deaths. The likelihood of IBD-related carcinoma is greater than that of sporadic CRC. Over one half are diagnosed at stage III or IV. During the last few years we have worked on mining colon mucosal and submucosal layers for discovery of biomarkers that differentiate ulcerative colitis (UC) from Crohn's colitis (CC). Using LC-MS/MS, we examined signals found to be significantly different between CC and UC samples. We found a signal at m/z 5045 which was more intense in UC samples. The MALDI spectrum did not identify an intact protein entity but did identify hemoglobin chains. Macrophages are highly versatile phagocytes active in multiple roles in the immune system and key players in the inflammatory response. The microenvironment of most inflammation is filled with a large population of macrophages. In IBD, studies have found that macrophages can count for more than 50% of the exudative mass. Their presence within the inflammatory microenvironment, in some cases, has been proven to increase transformation, angiogenesis, and immunosuppression. In hemorrhagic situations (as in UC) macrophages engulf erythrocytes and as a result release free heme iron (heFe). Earlier studies observed that heFe has cellular proliferation effects on colon cancer cells. Recently, the potential carcinogenic effects of heFe were documented when it was shown that heFe increases the number of aberrant crypt foci in colon mucosa. In the colon, iron is expected to increase the production of reactive oxygen (O2) species (ROS) from peroxides via the Fenton reaction, which may be the cause of cellular toxicity and even pro-mutagenic lesions. Intracellular reactions with active O2 can result in the initiation and progression of carcinogenesis by induction of gene mutations, chromosomal damage and cytotoxic effects. We hypothesize that elevated expression of mucosal free heFe would be associated with an increased risk of UC-associated CRC. To validate this will require investigating whether hemoglobin could be classified as a proliferative or transforming agent for colon cancer cells by causing reactive oxygen species release. For this purpose, we plan to study the cellular viability of differentiated colon cell line (cancer: CCL 224, CCL 227 and normal: NCM 356 and NCM 460) after administration of hemoglobin at different concentrations. ROS production will be investigated in each step. Additionally, we intend to examine the potential cytotoxicity of hemoglobin. Supported: MMC-VICC Cancer Partnership Grant # 3U54CA091408-09S 1 (SEA & HLM); MeTRC grant # 5U54RR026140-03 (SEA), and Vanderbilt SPORE in GI Cancer Grant # P50CA095103

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2058. doi:1538-7445.AM2012-2058

Bone marrow transplantation restores follicular maturation and steroid hormones production in a mouse model for primary ovarian failure

Recent studies suggest that bone marrow stem cells (BMSCs) are promising grafts to treat a variety of diseases, including reproductive dysfunction. Primary ovarian failure is characterized by amenorrhea and infertility in a normal karyotype female, with an elevated serum level of follicle-stimulating hormone (FSH) and a decrease level of estrogen caused by a mutation in FSH receptor (FSHR) gene. Currently, there is no effective treatment for this condition. The phenotype of FSHR (−/−) mouse, FORKO (follitropin receptor knockout), is a suitable model to study ovarian failure in humans. Female FORKO mice have elevated FSH, decreased estrogen levels, are sterile because of the absence of folliculogenesis, and display thin uteri and small nonfunctional ovaries. In this study, we determined the effects of BMSC transplantation on reproductive physiology in this animal model. Twenty four hours post BMSC transplantation, treated animals showed detectable estroidogeneic changes in daily vaginal smear. Significant increase in total body weight and reproductive organs was observed in treated animals. Hemotoxylin and eosin (H&E) evaluation of the ovaries demonstrated significant increase in both the maturation and the total number of the follicles in treated animals. The FSH dropped to 40–50% and estrogen increased 4–5.5 times in the serum of treated animals compared to controls. The FSHR mRNA was detected in the ovaries of treated animals. Our results show that intravenously injected BMSCs were able to reach the ovaries of FORKO mice, differentiate and express FHSR gene, make FSHR responsive to FSH, resume estrogen hormone production, and restore folliculogenesis.

Subungual melanoma: diagnosis and management

Subungual Melanoma accounts for less than three percent of all cutaneous melanomas and has a dismal prognosis. Our case report outlines the current approach for diagnosis and management of this rare form of acral lentiginous melanoma.

Abstract A45: Molecular targets in early detection and differentiation of inflammatory bowel disease-associated colon-rectal-anal cancer disparities

The inflammatory bowel disease (IBD), Crohn's (CC) and ulcerative colitis (UC), affect approximately 1–2 of every 1000 people in developed countries. These chronic inflammatory diseases result in significant morbidity and mortality. All IBD-associated colorectal-anal cancers (CRAC) occurred in segments of colitis and are frequently diagnosed at an advanced stage. This presentation is a continuation of our work that investigates potential molecules that could define a unique classifier between CC and UC and early detection of CRAC.

There are multiple challenges to identifying protein classifiers suggesting outcome prediction and differentiation for patients with IBD and/or IBD-CRAC from molecular interpretation standpoints is complex. While there are technical approach advances, the goal is clear however: to produce scientific evidence which can provide personalized expert care to patients.

We have developed an amenable proteomic methodology that supports the diagnostic feasibility to discriminate molecularly, different inflammatory colitis. The histologic layers of colectomy samples from patients with confirmed UC and CC tissues were analyzed using matrix-assisted laser de-sorption/ionization mass spectrometry (MALDI MS) for proteomic profiling.

Our previous findings (1) prompted further sample collection resulting in an increased sample size that would allow a more robust analysis. The samples from colon tissues collected in 2008 and samples collected in 2010 were re-randomized into training and independent test sets in order to avoid systematic differences between new and old data sets, typical for MALD-ToF spectra acquired in situ from tissue at different times. MALDI-ToF spectra were included in the analysis only for samples containing more than 3 unique spectra. Our studies have successfully identified 11 highly significant mass-to-charge ratio (m/z) signals (m/z 5045, 6139, 9245, 8413, 3666, 3595, 4122, 8774, 2778, 9232 and 9519) that distinguish CC from UC. These features are independent of the tissue of origin and represent disease specific markers. Some of these signatures were only found in the colonic mucosa (m/z 8413, 3666 & 3595) or submucosa (m/z 4122, 8774, 2778, 9232 & 9519) while others were found in both two layers (m/z 5045, 6139 & 9245). This information may provide new avenues for the development of novel diagnostic, prognostic and therapeutic targets. We will analyze CRAC in IBD segments2,3 to look for these proteins that may help in studying their biological mechanisms in cancer transformation.

Support: 3U54CA091408-09S1 (to MMC-VICC Partnership: SE Adunyah & HL Moses)

References:

1. M'Koma AE, Seely EH, Washington MK, Schwartz DA, Muldoon RL, Herline AJ, Wise PE, Caprioli RM Proteomic Profiling of Mucosal and Submucosal Colonic Tissues Yields Protein Signatures that Differentiate the Inflammatory Colitides. Inflamm Bowel Dis 2011;17:875-83.

2. M'Koma AE, Moses HL, Adunyah SE. Inflammatory bowel disease-associated colorectal cancer: proctocolectomy andmucosectomy does not necessarily eliminate pouch related cancer incidences. Int J colorect Dis 2011;26:533-52.

3. Um JW, M'Koma AE. Pouch-related dysplasia and adenocarcinoma following restorative proctocolectomy for ulcerative colitis. Tech coloproctol 2011;15:7-16.

Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):A45.

Toward gene therapy of premature ovarian failure: intraovarian injection of adenovirus expressing human FSH receptor restores folliculogenesis in FSHR(-/-) FORKO mice

A homozygous missense mutation, C566T, in the follicle stimulation hormone receptor (FSHR) gene has been linked to premature ovarian failure. The disease leads to infertility in a normal karyotype female with an elevated follicle stimulating hormone (FSH) and decreased serum estrogen level. Female mice carrying mutated FSHR gene, called follitropin receptor knockout (FORKO), display similar phenotype and are sterile because of a folliculogenesis block at a primary stage. We investigated the effects of bilateral intra-ovarian injection of an adenovirus expressing a normal copy of human FSHR on the reproductive system of 6-10 weeks female FORKO mice. Ad-LacZ was injected directly into each ovary of the control group. Animals were sacrificed at 2, 4, 8 and 12 weeks post-injection and tissues collected for evaluation. Treated mice showed estrogenic changes in daily vaginal smear whereas control animals remained fixated in the diestrus stage. Histological evaluation showed on average 26 +/- 4 follicles/ovary in treated group with 8 +/- 2 follicles at the antral stage compared with only 5 +/- 2 with zero follicles at antral stage in Ad-LacZ control mice. There was no significant change in serum level of progesterone, however, estrogen level increased 2-3-fold (P < 0.02) and FSH decreased by up to 50% (P < 0.04) in treated animals. FSHR mRNA was detected in the ovaries of the treated group. In conclusion, intra-ovarian injection of an adenovirus expressing human FSHR gene is able to restore FSH responsiveness and reinitiate ovarian folliculogenesis as well as resume estrogen production in female FORKO mice. Ad-LacZ injections indicate the absence of systemic viral dissemination or germ line transmission of adenovirus DNA to offspring.

The STAT4 and STAT6 Pathways in Pancreatitis-Associated Lung Injury

BACKGROUND

The STAT pathways are integral to the inflammatory response and these proteins provide a direct link between the cytokine receptors and cytokine-induced gene transcription. We examined the roles of STAT4 and STAT6 in lung injury after caerulein-induced severe acute pancreatitis. We hypothesized that a modified organ expression of cytokines and chemokines that occurs in transgenic mice may affect the systemic response to severe acute pancreatitis.

METHODS

Acute pancreatitis [13-hourly intraperitoneal injections of caerulein (50 microg/kg body weight, 0.2 mL) or the same volume of saline] was induced in wild-type (BALB/c) and transgenic (STAT4 or STAT6) mice of the same background, 7 to 8 weeks old. The pancreatic and lung tissues were collected at 1, 6, 12, and 24 h after the completion of caerulein administration. Tissue leukocyte sequestration was assessed by myeloperoxidase (MPO) activity. Standard histological staining hematoxylin and eosin was performed and blindly scored by a pathologist for evidence of lung injury (pulmonary edema, accumulations of neutrophils and mononuclear cells, thickness of alveolar-capillary membrane, perivascular infiltrate, and hemorrhage).

RESULTS

Caerulein-treated wild-type mice exhibited increased lung injury score at 1 through 12 h, as compared to saline controls. As compared to wild-type, STAT6-deficient mice had increased lung injury from 1 to 6 h, with full recovery by 12 h. An opposite pattern was observed in STAT4-deficient mice with mild injury seen at 1 and 6 h, and maximal injury at 12 h. MPO activity was significantly increased at 6 h in caerulein-treated wild-type mice compared to saline-treated controls. Caerulein-treated STAT6 and STAT4 mice had markedly increased MPO activity as compared with their saline controls during the first 6 h. Both caerulein-treated STAT4- and STAT6-deficient mice had significantly increased MPO activity in comparison with wild-type mice with pancreatitis at 6 h.

CONCLUSION

We found the maximal lung injury after caerulein-induced pancreatitis occurred at different time-points in STAT4 and STAT6-deficient mice. These temporal differences may suggest alternative roles in the systemic inflammatory response associated with pancreatitis.

Beneficial effects of soy protein in the initiation and progression against dimethylbenz [a] anthracene-induced breast tumors in female rats

This study was to demonstrate by histological grading whether soy protein protects against dimethylbenz[a]anthracene (DMBA) -induced breast tumors in female rats. At 25 days of age, rats were fed diets containing either casein or soy protein. After 25 days on diets, a single dose of DMBA in sesame oil (80 mg/kg) was administered by gavage. All tumors were detected by palpation. The number of tumors per rat was less in soy group than that in casein group at any time point up to 122 days after DMBA administration. Incidence of tumors was less in soy protein group than that in casein group. Casein group had 20% grade I, 60% grade II, and 20% grade III adenocarcinoma. However, the soy group had 100% grade I adenocarcinoma and no aggressive grade II or grade III tumor. There was a delay in the development of tumor in the soy protein group in comparison to the casein group. Again, unlike casein, the soy group had cessation of angiogenesis at several sites of tumor, and reduced levels of angiogenic markers, VEGF and bFGF. Immunohistochemical analysis of the breast tissues did not show any CD-31 positive stain in soy protein group, whereas some CD-31 positive stain was revealed in casein group, which further suggests that soy protein controls angiogenesis. Furthermore, proliferative index as assessed by Ki-67 staining was less in soy protein group than that in casein group. These findings suggest that the soy protein may protect against the development of a more aggressive breast carcinoma.

Transduodenal excision of bleeding periampullary endocrine tumor as a bridge to pancreaticoduodenectomy in a Jehovah's Witness patient

We discuss the case of a Jehovah's Witness patient who presented with a bleeding endocrine periampullary mass. Transduodenal excision of the ampullary mass was successfully performed as a bridge to pancreaticoduodenectomy in this critically ill patient. The roles of pancreaticoduodenectomy and alternatives to pancreaticoduodenectomy in the emergency setting are reviewed, in particular, for patients who decline transfusion of blood products. The surgical approach to surgery and perioperative anemia in Jehovah's Witness patients is described. Finally, we reviewed the role of transduodenal excision in the management of ampullary tumors and describe its use as a bridge to pancreaticoduodenectomy in a patient with a malignant neoplasm of the ampulla.

Do adverse histopathologic findings in colorectal cancer patients explain disparate outcomes?

We have previously reported reduced overall and disease-free survival in black patients from a 10-year retrospective review of 668 patients from tumor registry data. This study of 213 patients reports the analysis of available archived tissue from a city hospital (n=44 patients, 53% black) and from a university medical center (n=169, 10.6% black). Two senior pathologists independently reviewed slides for predetermined histologic criteria reported to correlate with survival: tumor type, stage at diagnosis, character of invasion, vascular or perineural invasion, the presence of residual adenoma, the presence of a Crohn's-like reaction and number of nodes resected. Differences in discrete variables were compared using the Chi-squared test. Differences in continuous variables were analyzed using independent t tests. No statistically significant differences were identified in tumor stage or type by institution or race. In patients treated at the city hospital, there was a higher incidence of infiltrating tumors (85% vs. 61%, p<0.001), vascular invasion (70% vs. 36%, p<0.05) and residual adenoma (84% vs. 39%, p<0.05); however, no differences by race were identified. Blacks at both hospitals had significantly more perineural invasion (81% vs. 30%, p<0.05) and Crohn's-like reaction (64% vs. 30%, p<0.05) when compared to white patients, although there was no difference between hospitals. The total number of lymph nodes resected was higher at the university hospital (17.0 vs. 8.9, p<0.001). There were no differences in number of nodes resected at either institution by race. Histopathologic findings did not explain the apparent disparity in survival. The differences in number of nodes harvested may suggest inadequate resection or insufficient recovery of nodes by the pathologist.

Is there disparity in the care of minority patients with upper aerodigestive tract malignancy?

The data presently available indicate that there is unequal (disparate) care in patients with head and neck cancer. The reasons for this are likely multifactorial and require further study. Complicating such work is the need for subgroup analysis. For example, Hispanics are not a homogeneous ethnic group; hence, differences in social perception, cultural mores, and available medical resources can be demonstrated that can directly impact care and outcome. Appropriate epidemiologic studies are needed with more underserved minority patients to analyze these differences further and to address such differences.

Heterozygous mutation of ataxia-telangiectasia mutated gene aggravates hypercholesterolemia in apoE-deficient mice

Individuals with a heterozygous mutation at the ataxia-telangiectasia mutated gene (ATM) have been reported to be predisposed to ischemic heart disease. This report examined for the first time the effect of a heterozygous ATM mutation (ATM(+)(/-)) on plasma lipid levels and atherosclerosis intensity using ATM(+/-), ATM(+)(/+) (wild type), ATM(+)(/+)/LDLR(-)(/-) (low density lipoprotein receptor knockout), ATM(+)(/-)/LDLR(-)(/-), ATM(+)(/+)/ApoE(-)(/-) (apolipoprotein E knockout), and ATM(+)(/-)/ApoE(-)(/-) mice. Our data demonstrated that the plasma cholesterol and triglyceride levels in ATM(+)(/-) and ATM(+)(/-)/LDLR(-)(/-) mice were approximately the same as those in ATM(+)(/+) and ATM(+)(/+)/LDLR(-)(/-) control mice, respectively. In contrast, the plasma cholesterol level was significantly higher in ATM(+)(/-)/ApoE(-)(/-) mice than in ATM(+)(/+)/ApoE(-)(/-) control mice. In addition, the ATM(+)(/-)/ApoE(-)(/-) mice showed higher plasma apoB-48 levels, slower clearance for plasma apoB-48-carrying lipoproteins, and more advanced atherosclerotic lesions in the aorta compared with the ATM(+)(/+)/ApoE(-)(/-) mice. These novel results suggest that the product of ATM is involved in an apoE-independent pathway for catabolism of apoB-48-carrying remnants; therefore, superimposition of a heterozygous ATM mutation onto an ApoE deficiency background reduces the clearance of apoB-48-carrying lipoproteins from the blood circulation and promotes the formation of atherosclerosis.

Metastatic pleomorphic carcinoma of lung presenting as abdominal pain

Pleomorphic carcinoma of lung is a rare subtype that has a propensity to metastasize to the small bowel. This rarely encountered tumor may present a diagnostic challenge to pathologists and result in delay that could impact clinical decisions. Lung cancer can metastasize to any organ in the body; however, clinical manifestations of metastasis to the small bowel are a relatively rare event. Because they are so rare, small-bowel metastases are usually seen only at autopsy. Clinical presentation of small-bowel metastasis of lung cancer may represent a terminal event if not recognized and surgically resolved. Prompt surgical intervention may significantly extend the life of the patient.

Retardation of atherosclerosis by overexpression of catalase or both Cu/Zn-superoxide dismutase and catalase in mice lacking apolipoprotein E

Oxidative stress has been suggested to potentiate atherogenesis. However, studies that have investigated the effect of antioxidants on atherosclerosis showed inconsistent results, ie, atherosclerosis was either retarded or not changed by dietary antioxidants. This report directly examined the effect of overexpressing Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and/or catalase on atherosclerosis and lipid peroxidation in mice lacking apolipoprotein E (ApoE-/-). Based on lipid staining of the en face of the aorta tree and the serial sections of the proximal aorta, ApoE-/- mice overexpressing catalase or both Cu/Zn-SOD and catalase had smaller and relatively early stages of atherosclerotic lesions (eg, foam cells and free lipids) when compared with ApoE-/- mice, who developed more advanced lesions (eg, fibrous caps and acellular areas). In addition, the retarded development of atherosclerosis was correlated with a reduced F2-isoprostanes in the plasma and aortas in ApoE-/- mice overexpressing catalase or both Cu/Zn-SOD and catalase. In contrast, the levels of F2-isoprostanes and atherosclerosis in the ApoE-/- mice overexpressing Cu/Zn-SOD alone were comparable to ApoE-/- control mice. These observations implied that endogenously produced hydrogen peroxide, but not superoxide anions, contributed to the formation of oxidized lipids and the development of atherosclerosis in ApoE-/- mice.

The establishment of minority affairs offices in schools of dentistry: pros and cons

The establishment of Minority Affairs Offices in dental schools following the American Association of Medical Colleges' model is discussed as one method of addressing the declining enrollment and compounding oral health disparities of underrepresented minorities African Americans, Hispanics, and Native Americans in U.S. dental schools. The pros and cons of the approach are discussed, with recommendations.

Malignant phyllodes tumor of the breast: review of the literature and case report of stromal overgrowth

Cystosarcoma phyllodes constitutes only 0.3-0.9% of all breast tumors. The term "sarcoma" was initially used because of its fleshy appearance, a more modern term is Phyllodes tumor (PT). The behavior of PT constitutes a spectrum from benign and locally recurrent to malignant and metastatic. In a general surgical series, 6.2% of the tumors were malignant. The microscopic appearance of PT is that of epithelial elements and connective tissue stroma. Malignancy is determined by characteristics of the stroma. The metastatic spread of malignant PT is mainly hematogenous to lung, with infrequent lymphatic involvement. Wide local excision with 2 cm margins is the treatment of choice. In 20% of both benign and malignant cases, PT will locally recur. There is no proven benefit of radiation or chemotherapy, although radiotherapy may be useful in selected cases. We present a case of a sarcomatous overgrowth in a malignant phyllodes tumor involving multiple histologic types.

Squamous-cell carcinoma of the floor of the mouth

This study was based on the analysis of 100 cases of squamous-cell carcinoma of the floor of the mouth. The male/female ratio was 4.25:1. The peak incidence in women was in the 50 to 59 year age group; in men there was equal frequency in each age group above 50. The five-year survival rate decreased from 86 per cent to 0 as the stage of disease progressed from I to IV. The five-year survival for all stages of disease was 52.7 per cent. Thirty-three per cent developed new primary malignancies; 22 per cent were of the upper alimentary and respiratory tracts. Distant metastases were present in 21 per cent. Fifty per cent were heavy smokers, 33 per cent were heavy drinkers, 28 per cent were both heavy smokers and heavy drinkers, and 21 per cent were nonsmokers and nondrinkers.