The Effects of Black Raspberry as a Whole Food-Based Approach on Biomarkers of Oxidative Stress in Buccal Cells and Urine of Smokers

Cigarette smoke is a rich source of free radicals that can promote oxidative stress and carcinogenesis, including head and neck squamous cell carcinoma (HNSCC) development; importantly, 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-iso-prostaglandin F2α (8-isoprostane) are biomarkers of oxidative stress. Several mechanisms, including the antioxidant properties of black raspberry (BRB), account for their chemopreventive effects. In the present clinical trial, we tested the hypothesis that BRB administration reduces biomarkers levels of oxidative stress in buccal cells and urine of smokers. One week after enrolling 21 smokers, baseline buccal cells and urine samples were collected before the administration of BRB lozenges for 8 weeks (5/day, 1 gm BRB/lozenge). Buccal cells and urine samples were collected at the middle and the end of BRB administration. The last samples were collected after the BRB cessation (washout period). We analyzed levels of 8-oxodG and 8-isoprostane (LC/MS-MS), urinary cotinine (ELISA), and creatinine (spectrophotometry). BRB significantly reduced the levels of 8-oxodG by 17.08% (P = 0.00079) in buccal cells and 12.44% (P = 0.034) in urine at the middle of BRB administration as compared with baseline; the corresponding values at the end of BRB administration were 16.46% (P = 0.026) in buccal cells and 25.72% (P = 0.202) in urine. BRB had no significant effect on the levels of urinary 8-isoprostane. BRB's capacity to inhibit 8-oxodG formation of smokers' buccal cells and urine is clearly evident and the reduction in 8-oxodG suggests that antioxidant abilities are central to BRB's HNSCC chemopreventive properties.

PREVENTION RELEVANCE

Cigarette smoke contains highly active components namely free radicals that can promote oxidative stress and oral cancer. We found that black raspberry (BRB) inhibited the formation of oxidative stress markers in the oral cavity and urine of smokers suggesting the antioxidant abilities of BRB in preventing oral cancer.

[Observation of the consistency between intellectualized and manual-based cognitive assessment tools in the outpatient clinic]

Objective: The intellectualized versions of the Montreal Cognitive Assessment Scale (MoCA) and the Mini-mental State Examination (MMSE) (i-MoCA/i-MMSE) were developed. The validity of this system was evaluated in a clinical sample through comparing with the manual-based assessments. Methods: A total of 88 patients [aged (66.82±11.37) years, 30 males and 58 females] were enrolled in the outpatient clinic of Xuanwu Hospital of Capital Medical University with complaints of cognitive decline, from February to October 2023. All participants completed manual-based and intellectualized assessments in a randomized order, with an interval of 2 weeks to control for the practice effect. The reliability of the intellectualized version of assessments was evaluated based on the manual-based version using the Concordance correlation coefficient (CCC). The difference between the intellectualized and the manual-based assessments was tested by the Repeated ANCOVA with demographic information controlled. The accuracy of evaluation of the i-MoCA and i-MMSE was analyzed by the Receiver Operating Characteristic (ROC) analysis. Results: High concordance was observed between the intellectualized version and the manual-based assessments (CCCMoCA=0.87, CCCMMSE=0.83). Controlling for basic demographic information, there was no significant difference in the scores of the intellectualized version and the manual-based assessments (all P>0.05). The accuracy of i-MoCA in screening patients with cognitive impairment was 94.3% (sensitivity=94.6%, specificity=78.1%), while the accuracy of i-MMSE in screening patients with cognitive impairment was 94.9% (sensitivity=94.9%, specificity=77.6%). In addition, the majority of subdomains measured by the cognitive assessments exhibited high consistency across the intellectualized the manual-based versions (CCCMoCA=0.32-0.78; CCCMMSE=0.54-0.79). Conclusion: Both the i-MoCA and i-MMSE showed high consistency and diagnostic accuracy with the manual-based versions in terms of overall cognitive function and subdomains.

Gender Difference in DNA Damage Induced by the Environmental Carcinogen Dibenzo[def,p]chrysene Individually and in Combination with Mouse Papillomavirus Infection in the Mouse Oral Cavity

Tobacco smoking and human papillomavirus infection are established etiological agents in the development of head and neck squamous cell carcinoma (HNSCC). The incidence and mortality of HNSCC are higher in men than women. To provide biochemical basis for sex differences, we tested the hypothesis that carcinogen treatment using dibenzo[def,p]chrysene, which is an environmental pollutant and tobacco smoke constituent, in the absence or presence of the mouse papillomavirus infection results in significantly higher levels of DNA damage in the oral cavity in male than in female mice. However, the results of the present investigation do not support our hypothesis since we found that females were more susceptible to carcinogen-induced covalent DNA damage than males independent of the viral infection. Since DNA damage represents only a single-step in the carcinogenesis process, additional factors may contribute to sex differences in humans.

[Advancements in research on para-aortic lymph node dissection in colorectal cancer]

Para-aortic lymph node metastasis from colorectal cancer is relatively rare. Recent studies have shown that curative para-aortic lymph node dissection can lead to similar prognoses as stage III colorectal cancer for selected patients. However, there are still many unresolved debates regarding the appropriate surgical indications, extent of lymph node dissection, and treatment principles for colorectal cancer patients with para-aortic lymph node metastasis. With the continuous improvement of laparoscopic colorectal surgery techniques, the previously complex and high-risk procedure of para-aortic lymph node dissection has now become a safe and feasible approach. However, there are still several challenges that need to be addressed in this field. It is imperative to conduct multicenter clinical studies to demonstrate the survival benefits of this surgical procedure into greater survival benefits. This will help generate more robust evidence in the field of evidence-based medicine.

Complementarity between Microbiome and Immunity May Account for the Potentiating Effect of Quercetin on the Antitumor Action of Cyclophosphamide in a Triple-Negative Breast Cancer Model

Immunotherapy targeting program cell death protein 1 (PD-1) in addition to chemotherapy has improved the survival of triple-negative breast cancer (TNBC) patients. However, the development of resistance and toxicity remain significant problems. Using the translationally relevant 4T1 mouse model of TNBC, we report here that dietary administration of the phytochemical quercetin enhanced the antitumor action of Cyclophosphamide, a cytotoxic drug with significant immunogenic effects that is part of the combination chemotherapy used in TNBC. We observed that quercetin favorably modified the host fecal microbiome by enriching species such as Akkermansia muciniphilia, which has been shown to improve response to anti-PD-1 therapy. We also show that quercetin and, to a greater extent, Cyclophosphamide increased the systemic frequency of T cells and NK cells. In addition, Cyclophosphamide alone and in combination with quercetin reduced the frequency of Treg, which is consistent with an antitumor immune response. On the other hand, Cyclophosphamide did not significantly alter the host microbiome, suggesting complementarity between microbiome- and immune-mediated mechanisms in potentiating the antitumor action of Cyclophosphamide by quercetin. Overall, these results support the potential for microbiota-centered dietary intervention to overcome resistance to chemoimmunotherapy in TNBC.

[Anatomical classification of and laparoscopic surgery for left-sided colorectal cancer with persistent descending mesocolon]

Objective: To investigate anatomical morphology and classification of persistent descending mesocolon (PDM) in patients with left-sided colorectal cancer, as well as the safety of laparoscopic radical surgery for these patients. Methods: This is a descriptive study of case series. Relevant clinical data of 995 patients with left colon and rectal cancer who had undergone radical surgery in Fujian Medical University Union Hospital from July 2021 to September 2022 were extracted from the colorectal surgery database of our institution and retrospectively analyzed. Twenty-four (2.4%) were identified as PDM and their imaging data and intra-operative videos were reviewed. We determined the distribution and morphology of the descending colon and mesocolon, and evaluated the feasibility and complications of laparoscopic surgery. We classified PDM according to its anatomical characteristics as follows: Type 0: PDM combined with malrotation of the midgut or persistent ascending mesocolon; Type 1: unfixed mesocolon at the junction between transverse and descending colon; Type 2: PDM with descending colon shifted medially (Type 2A) or to the right side (Type 2B) of the abdominal aorta at the level of the origin of the inferior mesentery artery (IMA); and Type 3: the mesocolon of the descending-sigmoid junction unfixed and the descending colon shifted medially and caudally to the origin of IMA. Results: The diagnosis of PDM was determined based on preoperative imaging findings in 9 of the 24 patients (37.5%) with left-sided colorectal cancer, while the remaining diagnoses were made during intraoperative assessment. Among 24 patients, 22 were male and 2 were female. The mean age was (63±9) years. We classified PDM as follows: Type 0 accounted for 4.2% (1/24); Type 1 for 8.3% (2/24); Types 2A and 2B for 37.5% (9/24) and 25.0% (6/24), respectively; and Type 3 accounted for 25.0% (6/24). All patients with PDM had adhesions of the mesocolon that required adhesiolysis. Additionally, 20 (83.3%) of them had adhesions between the mesentery of the ileum and colon. Twelve patients (50.0%) required mobilization of the splenic flexure. The inferior mesenteric artery branches had a common trunk in 14 patients (58.3%). Twenty-four patients underwent D3 surgery without conversion to laparotomy; the origin of the IMA being preserved in 22 (91.7%) of them. Proximal colon ischemia occurred intraoperatively in two patients (8.3%) who had undergone high ligation at the origin of the IMA. One of these patients had a juxta-anal low rectal cancer and underwent intersphincteric abdominoperineal resection because of poor preoperative anal function. Laparoscopic subtotal colectomy was considered necessary for the other patient. The duration of surgery was (260±100) minutes and the median estimated blood loss was 50 (20-200) mL. The median number of No. 253 lymph nodes harvested was 3 (0-20), and one patient (4.2%) had No.253 nodal metastases. The median postoperative hospital stay was 8 (4-23) days, and the incidence of complications 16.7% (4/24). There were no instances of postoperative colon ischemia or necrosis observed. One patient (4.2%) with stage IIA rectal cancer developed Grade B (Clavien-Dindo III) anastomotic leak and underwent elective ileostomy. The other complications were Grade I-II. Conclusions: PDM is frequently associated with mesenteric adhesions. Our proposed classification can assist surgeons in identifying the descending colon and mesocolon during adhesion lysis in laparoscopic surgery. It is crucial to protect the colorectal blood supply at the resection margin to minimize the need for unplanned extended colectomy, the Hartmann procedure, or permanent stomas.

Development of a high-speed small-angle infrared thermography system in EAST

A high-speed infrared small-angle infrared thermography system (SATS) has been developed and installed on the Experimental Advanced Superconducting Tokamak (EAST) for measuring the surface temperature of the divertor target to calculate the high heat flux induced by Edge Localized Modes (ELMs) and providing observation means for the further physical study of some key parameters, such as power decay length λq and the characteristic time of different types of ELMs. An endoscopic optical system is applied to realize the SATS for clear imaging of the divertor plate area and protection from the harm of impurity deposition and latent tungsten ablation during discharge. The field of view (FOV) of the endoscopic optical system is designed to be 13° in the horizontal direction and 9° in the vertical direction. As a consequence, ∼35° of coverage of the lower-outer divertor and a small part of the lower-inner divertor in toroidal are covered by the FOV with a spatial resolution of around 2 mm/pixel. This paper presents a detailed description of the new SATS and the preliminary experimental diagnostic results. The radial distribution of heat flux induced by an ELM crash was demonstrated.

Abstract 4245: Effects of black raspberries extract on DNA repair capacity and metabolic activation/detoxification of the tobacco carcinogen dibenzo[def,p] in human oral cells

We previously reported that black raspberries (BRB) powder inhibits dibenzo[def,p]chrysene (also known as dibenzo[a,l]pyrene; DBP)-induced DNA damage, mutagenesis and carcinogenesis in the mouse oral cavity. The effects of BRB on the capacity of DNA repair was investigated in an established in vitro system using HeLa cells to assess the DNA repair capacity. We found that pre-treatment of Hela cells with BRB extracts (BRBE) can enhance the nucleotide excision repair (NER) of a bulky DNA adduct derived from the tobacco oral carcinogen benzo[a]pyrene by ~24% and this effect is correlated with the enhanced expressions of NER factors XPA and XPB. The NER activity of guanidinohydantoin (Gh), an oxidatively-derived non-bulky DNA lesion, is also enhanced by ~24%, while its base excision repair activity is enhanced by only ~6%. Using human oral leukoplakia (MSK-Leuk1) and oral squamous cell carcinoma SCC1483, we demonstrated that BRBE can inhibit DNA damage induced by DBP through the induction of GSH synthesis and enhancing GSH conjugates thereby inhibiting DNA damage. The effects of BRBE in MSK-Leuk1 and SCC1483 cells were further investigated on the DNA excision repair protein ERCC1 at 1, 6 and 24 h. ERCC1 forms the ERCC1-XPF enzyme complex that participates in several DNA repair pathways. Western blot analyses revealed that BRBE induced higher ERCC1 expression in SCC1483 than those observed in MSK-Leuk1 cells in a time-dependent manner. The results of our study demonstrate that BRBE is capable of inhibiting the metabolic activation, enhancing the detoxification pathway and DNA repair capacity which are consistent with its chemopreventive activity in vivo. Supported by NIH grant #CA173465.

Citation Format: Yuan-Wan Sun, Kun-Ming Chen, Ana H. Sales, Nicholas Geacintov, Karam El-Bayoumy. Effects of black raspberries extract on DNA repair capacity and metabolic activation/detoxification of the tobacco carcinogen dibenzo[def,p] in human oral cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4245.

The study on bactericidal effect and ultrastructural alterations of chlorocresol nanoemulsion disinfectant against Staphylococcus aureus

Chlorocresol nanoemulsion disinfectant (CND) is an environmental disinfectant prepared with nanoemulsion as its drug carrier. This study aimed to investigate the bactericidal effect of CND on Staphylococcus aureus ( S. aureus) and its effect on bacterial ultrastructure. The neutralizing effect of CND against S. aureus was first screened by suspension quantitative evaluation experiment procedure of neutralizer. Disinfection performance was evaluated by the determination of Minimal Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC), quantitative bactericidal experiment, and comparative experiment of disinfection performance between 0.1% CND and 0.1% chlorocresol aqueous solution. Meanwhile, the effect of CND on the ultrastructure of S. aureus was investigated with scanning electron microscope (SEM) and transmission electron microscope (TEM) to preliminarily explore the bactericidal mechanism. The results showed that 3% Tween-80 in PBS could be screened as the neutralizer of CND against S. aureus. MIC and MBC were 100 μg/mL and 200 μg/mL, respectively. The bactericidal rates were all 100% when 0.06% and 0.08% disinfectant acted for 15 and 5 min, respectively. Furthermore, compared with 0.1% chlorocresol aqueous solution, the bactericidal effect of 0.1% CND was significantly enhanced (p⟨0.01). After treatment with CND for 10 min, SEM observation showed that the morphology of S. aureus cells were changed and the integrity destroyed. TEM observation showed that the cell shape changed, and the structures of the cell wall, cell membrane and cytoplasm were damaged in varying degrees. CND showed the strong bactericidal effect on S. aureus and could cause ultrastructure alterations of S. aureus.

Black Raspberry Extract Enhances Glutathione Conjugation of the Fjord-Region Diol Epoxide Derived from the Tobacco Carcinogen Dibenzo[def,p]chrysene in Human Oral Cells

In a series of previous studies we reported that black raspberry (BRB) powder inhibits dibenzo[a,l]pyrene (DBP)-induced DNA damage, mutagenesis, and oral squamous cell carcinoma (OSCC) development in mice. In the present study, using human oral leukoplakia (MSK-Leuk1) and squamous cell carcinoma (SCC1483) cells, we tested the hypothesis that BRB extract (BRBE) will enhance the synthesis of glutathione (GSH) and in turn increase GSH conjugation of the fjord-region DBP diol epoxide (DBPDE) derived from DBP leading to inhibition of DBP-induced DNA damage. The syntheses of DBPDE-GSH conjugate, DBPDE-dA adduct, and the corresponding isotope-labeled internal standards were performed; LC-MS/MS methods were used for their quantification. BRBE significantly (p < 0.05) increased cellular GSH by 31% and 13% at 6 and 24 h, respectively, in OSCC cells; in MSK-LeuK1 cells, the levels of GSH significantly (p < 0.05) increased by 55% and 22%, at 1 and 6 h. Since BRBE significantly enhanced the synthesis of GSH in both cell types, subsequent experiments were performed in MSK-Leuk1 cells. Western blot analysis was performed to determine the types of proteins involved in the synthesis of GSH. BRBE significantly (p < 0.05) increased the protein expression (2.5-fold) of the glutamate-cysteine ligase catalytic subunit (GCLC) but had no effect on the glutamate-cysteine ligase modifier subunit (GCLM) and glutathione synthetase (GSS). LC-MS/MS analysis showed that pretreatment of cells with BRBE followed by DBPDE significantly (p < 0.05) increased the levels of DBPDE-GSH conjugate (2.5-fold) and decreased DNA damage by 74% measured by assessing levels of DBPDE-dA adduct formation. Collectively, the results of this in vitro study clearly support our hypothesis, and the LC-MS/MS methods developed in the present study will be highly useful in testing the same hypothesis initially in our mouse model and ultimately in smokers.

Detection of DNA adducts derived from the tobacco carcinogens, benzo[a]pyrene and dibenzo[def,p]chrysene in human oral buccal cells

Polycyclic aromatic hydrocarbons (PAHs) are recognized as potential etiological agents in the development of oral cancer in smokers. In particular, benzo[a]pyrene (B[a]P) and dibenzo[def,p]chrysene (DB[a,l]P) are detected in cigarette smoke and the environment and can induce DNA damage, mutagenesis and carcinogenesis in the oral cavity of rodents. Consequently, DNA adducts are regarded as the most direct markers of genotoxicity and can be used as biomarkers of cancer risk. Thus, this study used LC-MS/MS analysis with isotope labeled internal standard to detect and quantify DNA adducts derived from B[a]P and DB[a,l]P in buccal cells of cigarette smokers and non-smokers. Participants in this study include 21 smokers and 16 non-smokers. Our data are the first to report that levels (mean ± SD) of BPDE-N2-dG were significantly (P < 0.001) higher in smokers (20.18 ± 8.40 adducts/108 dG) than in non-smokers (0.84 ± 1.02 adducts/108 dG). Likewise, levels of DBPDE-N6-dA in smokers (5.49 ± 3.41 adducts/108 dA) were significantly higher (P = 0.019) than non-smokers (2.76 ± 2.29 adducts/108 dA). Collectively, the results of this clinical study support that PAHs in tobacco smoke can contribute to the development of oral cancer in humans.

Black raspberry restores the expression of the tumor suppressor p120ctn in the oral cavity of mice treated with the carcinogen dibenzo[a,l]pyrene diol epoxide

One of the major risk factors for head and neck squamous cell carcinoma (HNSCC) is tobacco smoke exposure, but the mechanisms that can account for disease development remain to be fully defined. Utilizing our HNSCC mouse model, we analyzed oral squamous cell carcinomas (OSCC) induced by the active metabolite of a common smoke constituent, dibenzo[a,l]pyrene diol-epoxide (DBPDE). Analyzing protein expression by either immunofluorescence or immunohistochemistry, we identified biologic processes that are dysregulated in premalignant and invasive cancer lesions induced by DBPDE. Interestingly, p120ctn expression is downregulated in both stages of the disease. In addition to decreased p120ctn expression, there was also increased proliferation (as measured by Ki67), inflammation (as measured by NFkB (p65) expression), neovascularization (as measured by CD31) and recruitment of Ly6G-positive immune cells as well as strong EGFR expression. We also examined the effect of the chemopreventive agent black raspberry (BRB) on p120ctn and EGFR protein expression in DBPDE treated mice. p120ctn, but not EGFR, protein expression increased in mice treated with BRB. Our results suggest that modulation of p120ctn may, in part, account for the mechanism by which BRB inhibits DBPDE induced OSCC in mice.

Effects of E-Cigarette Aerosols with Varying Levels of Nicotine on Biomarkers of Oxidative Stress and Inflammation in Mice

To provide insights into the cause of e-cigarette (e-cig) associated lung injury, we examined the effects of propylene glycol (PG) and glycerol (G), two common solvent carriers used to deliver nicotine/flavor, on markers of oxidative stress and inflammation in female B6C3F1 mice which had been used successfully in tobacco smoke (TS)-induced lung carcinogenesis. Mice exposed to air and TS were used as negative and positive controls, respectively. Using LC-MS/MS, we showed that PG/G alone, in the absence of nicotine, significantly increased the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG or its tautomer 8-oxodG), a biomarker of DNA oxidative damage, in lung and plasma of mice; moreover, addition of nicotine (12 and 24 mg/mL) in e-cig liquid appears to suppress the levels of 8-oxodG. Exposure to e-cig aerosols or TS induced nonsignificant increases of plasma C-reactive protein (CRP), a biomarker of inflammation; nonetheless, the levels of fibronectin (FN), a biomarker of tissue injury, were significantly increased by e-cig aerosols or TS. Although preliminary, our data showed that exposure to e-cig aerosols induced a higher score of lung injury than did control air or TS exposure. Our results indicate that the B6C3F1 mouse model may be suitable for an in-depth examination of the impact of e-cig on lung injury associated with oxidative stress and inflammation and this study adds to the growing evidence that the use of e-cig can lead to lung damage.

[Source investigation on a familiar cluster of coronavirus disease 2019 in Dandong city of Liaoning Province]

To Track the source of the infection through an investigation of a clustering of coronavirus disease 2019(COVID-19), and provide scientific basis and Strategy for the effective control of the aggregated epidemic situation of COVID-19. Field epidemiological method was used to survey the cases and related close contacts in a family clustering epidemic of COVID-19 in Dandong city of Liaoning Province. We obtained survey data for a descriptive analysis.Real time RT-PCR technique was used to detect 2019-nCoV nucleic acid in samples collected from cases and related close contacts combined with serum specific antibody detection. A total of 3 confirmed cases and 2 asymptomatic infection cases were discovered in the clustering epidemic, with 34 close contacts.Of eight close family contacts visiting from other province, one patient was on the same flight as the confirmed case, and her antibody IgG was positive. The family clustering was caused by past infection case who visited her friend through Wuhan from other provinces to local area.

The environmental pollutant and tobacco smoke constituent dibenzo[def,p]chrysene is a co-factor for malignant progression of mouse oral papillomavirus infections

HPV infections in the oral cavity that progress to cancer are on the increase in the USA. Model systems to study co-factors for progression of these infections are lacking as HPVs are species-restricted and cannot grow in preclinical animal models. We have recently developed a mouse papillomavirus (MmuPV1) oral mucosal infection model that provides opportunities to test, for the first time, the hypothesis that tobacco carcinogens are co-factors that can impact the progression of oral papillomas to squamous cell carcinoma (SCC). Four cohorts of mice per sex were included: (1) infected with MmuPV1 and treated orally with DMSO-saline; (2) infected with MmuPV1 and treated orally with the tobacco carcinogen, dibenzo[def,p]chrysene (DBP); (3) uninfected and treated orally with DMSO-saline, and (4) uninfected and treated orally with DBP. Oral swabs were collected monthly for subsequent assessment of viral load. Oral tissues were collected for in situ viral DNA/RNA detection, viral protein staining, and pathological assessment for hyperplasia, papillomas and SCC at study termination. We observed increased rates of SCC in oral tissue infected with MmuPV1 and treated with DBP when compared to mice treated with DBP or virus individually, each of which showed minimal disease. Virally-infected epithelium showed strong levels of viral DNA/RNA and viral protein E4/L1 staining. In contrast, areas of SCC showed reduced viral DNA staining indicative of lower viral copy per nucleus but strong RNA signals. Several host markers (p120 ctn, p53, S100A9) were also examined in the mouse oral tissues; of particular significance, p120 ctn discriminated normal un-infected epithelium from SCC or papilloma epithelium. In summary, we have confirmed that our infection model is an excellent platform to assess the impact of co-factors including tobacco carcinogens for oral PV cancerous progression. Our findings can assist in the design of novel prevention/treatment strategies for HPV positive vs. HPV negative disease.

An Integrated Approach for Preventing Oral Cavity and Oropharyngeal Cancers: Two Etiologies with Distinct and Shared Mechanisms of Carcinogenesis

Head and neck squamous cell carcinoma (HNSCC) was the 7th most common malignancy worldwide in 2018 and despite therapeutic advances, the overall survival rate for oral squamous cell carcinoma (OSCC; ∼50%) has remained unchanged for decades. The most common types are OSCC and oropharyngeal squamous cell carcinoma (OPSCC, survival rate ∼85%). Tobacco smoking is a major risk factor of HNSCC. In the developed world, the incidence of OSCC is declining as a result of tobacco cessation programs. However, OPSCC, which is also linked to human papillomavirus (HPV) infection, is on the rise and now ranks as the most common HPV-related cancer. The current state of knowledge indicates that HPV-associated disease differs substantially from other types of HNSCC and distinct biological differences between HPV-positive and HPV-negative HNSCC have been identified. Although risk factors have been extensively discussed in the literature, there are multiple clinically relevant questions that remain unanswered and even unexplored. Moreover, existing approaches (e.g., tobacco cessation, vaccination, and chemoprevention) to manage and control this disease remain a challenge. Thus, in this review, we discuss potential future basic research that can assist in a better understanding of disease pathogenesis which may lead to novel and more effective preventive strategies for OSCC and OPSCC.

Black Raspberry Inhibits Oral Tumors in Mice Treated with the Tobacco Smoke Constituent Dibenzo(def,p)chrysene Via Genetic and Epigenetic Alterations

We previously reported that the environmental pollutant and tobacco smoke constituent dibenzo[def,p]chrysene (DBP) induced DNA damage, altered DNA methylation and induced oral squamous cell carcinoma (OSCC) in mice. In the present study, we showed that 5% dietary black raspberry (BRB) significantly reduced (P < 0.05) the levels of DBP-DNA adducts in the mouse oral cavity with comparable effect to those of its constitutes. Thus, only BRB was selected to examine if aberrant DNA methylation induced by DBP can be altered by BRB. Using comparative genome-wide DNA methylation analysis, we identified 479 hypermethylated and 481 hypomethylated sites (q < 0.01, methylation difference >25%) between the oral tissues of mice treated with DBP and fed control diet or diet containing BRB. Among the 30 differential methylated sites (DMS) induced by DBP, we found DMS mapped to Fgf3, Qrich2, Rmdn2, and Cbarp were hypermethylated by BRB whereas hypomethylated by DBP at either the exact position or proximal sites; DMS mapped to Vamp3, Ppp1rB1, Pkm, and Zfp316 were hypomethylated by BRB but hypermethylated by DBP at proximal sites. In addition to Fgf3, 2 DMS mapped to Fgf4 and Fgf13 were hypermethylated by BRB; these fibroblast growth factors are involved in regulation of the epithelial-mesenchymal transition (EMT) pathway as identified by IPA. Moreover, BRB significantly reduced (P < 0.05) the tumor incidence from 70% to 46.7%. Taken together, the inhibitory effects of BRB on DNA damage combined with its effects on epigenetic alterations may account for BRB inhibition of oral tumorigenesis induced by DBP. SIGNIFICANCE: We provided mechanistic insights that can account for the inhibition of oral tumors by BRB, which could serve as the framework for future chemopreventive trials for addicted smokers as well as non- or former smokers who are exposed to environmental carcinogens.

[Identification of gene biomarkers to predict responses to neoadjuvant chemoradiotherapy in patients with rectal cancer and pathways enrichment analysis]

Objective: To screen out the potential gene biomarkers to predict responses to neoadjuvant chemoradiotherapy (CRT) in patients with rectal cancer and to explore the main downstream pathways of resistance. Methods: The gene expression profiles (GSE35452) of locally advanced rectal cancer undergoing neoadjuvant chemoradiotherapy from 46 specimens (24 responders, TRG 0/1, and 22 non-responders, TRG 2/3) were downloaded from the GEO database. The differentially expressed genes were identified to screen out the potential biomarkers by use of the GCBI platform. GO and KEGG pathways enrichment analysis were performed to integrate enrichment results of differentially expressed genes. Signal-signal interaction network was constructed and analyzed to screen out potential main downstream pathways. Results: A total of 1079 differentially expressed genes were screened, including 657 up-regulated and 422 down-regulated ones. Among these genes, REG4 had the maximum fold change value of -6.029 491. In GO term, these differentially expressed genes were mainly enriched in molecule metabolic process, cell cycle, DNA-dependent transcription, signal transduction and apoptotic process. The KEGG pathways enrichment analysis showed that the differentially expressed genes were enriched in 65 KEGG pathways, including metabolic pathways, cell cycle and metabolism pathways. Signal-signal interaction network analysis showed that MAPK signaling pathway and cell cycle pathway might play a determinant role in the development of neoadjuvant chemoradiotherapy resistance. Further analysis showed that CDKN1B, CDKN2A, RBL1, TFDP1, CCND2, CCNE2, CDC6 and CDK6 in cell cycle might induce chemoradiotherapy resistance by blocking G1/S phase cell cycle arrest, decreasing the apoptosis of tumor cells and increasing S phase ratio of chemoradiotherapy resistance. Conclusion: G1/S phase cell cycle arrest blocking plays an important role in the development of chemoradiotherapy resistance in patients with rectal cancer. Moreover, the key genes, such as REG4, may be useful in predicting responses to neoadjuvant chemoradiotherapy.

3D Strain in 2D Materials: To What Extent is Monolayer Graphene Graphite?

This work addresses a fundamental question: To what extent is graphene graphite? In particular does 2D graphene have many of the same 3D mechanical properties as graphite, such as the bulk modulus and elastic constant c_{33}? We have obtained, for the first time, unambiguous Raman spectra from unsupported monolayer graphene under pressure. We have used these data to quantify the out-of-plane stiffness of monolayer graphene, which is hard to define due to its 2D nature. Our data indicate a first physically meaningful out-of-plane stiffness of monolayer graphene, and find it to be consistent with that of graphite. We also report a shift rate of the in-plane phonon frequency of unsupported monolayer graphene to be 5.4  cm^{-1} GPa^{-1}, very close to that of graphite (4.7  cm^{-1} GPa^{-1}), contrary to the previous value for supported graphene. Our results imply that monolayer graphene has similar in-plane and out-of-plane stiffnesses, and anharmonicities to graphite.

[Clinicopathological study of SET subtype of ovarian high-grade serous carcinoma]

Objective: To investigate the clinicopathological characteristics and significance of solid, endometrioid and transitional (SET) ovarian high-grade serous carcinoma (HGSC). Methods: A total of 408 cases of ovarian HGSC admitted to Peking University People's Hospital from January 2011 to September 2016 were collected. (1) According to the proportion of tumors with SET form in all tumors, they were divided into three groups: HGSC-classic group (<25%), HGSC-SET Ⅰ (25%-50%) and HGSC-SET Ⅱ (>50%) group. The clinical and pathological characteristics of three groups of ovarian HGSC patients were compared respectively. (2) According to the growth pattern, that was, the proportion of pushing/expanding invasive tumors in the whole pelvic disseminated tumors of pelvic disseminated tumors, the three groups were divided into four subgroups: group A (0-25%), group B (26%-50%), group C (51%-75%) and group D (>75%). Differences in progression-free survival (PFS) among the four subgroups in each group were compared respectively. Results: The median age of 408 cases with ovarian HGSC was 63.3 years (47-78 years), including 152 cases premenopausal and 256 cases postmenopausal. Among 408 cases of ovarian HGSC, 290 cases were in HGSC-classic group, 91 cases in HGSC-SET Ⅰ and 27 cases in HGSC-SET Ⅱ group. (1) There were significant differences in age, proportion of menopausal patients, tumor necrosis (including map necrosis or acne necrosis), response rate to primary chemotherapy, 5-year mortality rate and PFS between HGSC-SET Ⅰ and HGSC-SET Ⅱ (P<0.05). There was no significant difference among the above indexes between HGSC-SET Ⅰ and HGSC-SET Ⅱ (P>0.05). In HGSC-classic group, HGSC-SET Ⅰ and HGSC-SET Ⅱ, the proportion of family members or patients with history of epithelial ovarian cancer or breast cancer increased in turn, and the detection rate of serous tutal intraepithelial carcinoma (STIC) in fallopian tube tissue decreased in turn. There were significant differences between the two groups (P<0.05). (2) In HGSC-classic group, there were 147 cases in group A, 124 cases in group B and 19 cases in group C (0 case in group D), with median PFS of 17.4, 17.7 and 16.5 months respectively (P<0.05); 10, 6, 29 and 46 cases in group A, B, C and D in HGSC-SET Ⅰ, with median PFS of 9.6, 12.7, 30.1 months and 39.0 months respectively, which there were significant difference among group A and C and D (all P<0.05); among group B, C and D group in HGSC-SET Ⅱ, there were respectively 3, 12 and 12 cases (0 case in group A), and the median PFS was 13.5, 34.2 and 47.8 months (P<0.05). PFS was positively correlated with the increase of push/expansive infiltration ratio. Conclusions: The detection rate of STIC in ovarian HGSC patients with SET is higher, the effect of primary chemotherapy is better, and PFS is prolonged. PFS was significantly prolonged in patients with pelvic disseminated tumors of HGSC-SET, the infiltration of which were predominated by pushing or expanding boarder.

Omega-3 Fatty Acids Responsive Proteins and Reduction in Breast Density in Obese Postmenopausal Women

We reported that breast density (BD) was inversely correlated with the plasma level of DHA in postmenopausal obese, but not in nonobese, women given Lovaza (n-3FA). To identify protein biomarkers for the possible differential effect of n-3FA on BD between obese and nonobese women, an iTRAQ method was performed to analyze plasma from obese and lean women at each time point (baseline, 12 and 24-months, n = 10 per group); 173 proteins with >95% confidence (Unuses Score >1.3 and local false discovery rate estimation <5%) were identified. Comparative analysis between various groups identified several differentially expressed proteins (hemopexin precursor, vitamin D binding protein isoform 1 precursor [VDBP], fibronectin isoform 10 precursor [FN], and α-2 macroglobulin precursor [A2M]). Western blot analysis was performed to verify the differential expression of proteins in the iTRAQ study, and those found to be altered in a tumor protective fashion by an n-3FA rich diet in our previous preclinical study; gelsolin, VDBP, and FN were altered by n-3FA in a manner consistent with reduction in inflammation in obese women. To test the impact of our findings on breast cancer risk reduction by n-3FA, a posthoc analysis revealed that n-3FA administration reduced BD selectively in obese postmenopausal women.

Effects of the Tobacco Carcinogens N'-Nitrosonornicotine and Dibenzo[a,l]pyrene Individually and in Combination on DNA Damage in Human Oral Leukoplakia and on Mutagenicity and Mutation Profiles in lacI Mouse Tongue

In previous studies, we showed that the topical application of dibenzo[a,l]pyrene (DB[a,l]P), also known as dibenzo[def,p]chrysene, to the oral cavity of mice induced oral squamous cell carcinoma. We also showed that dA and dG adducts likely account for most of the mutagenic activity of DB[a,l]P in the oral tissues in vivo. Here we report for the first time that the oral treatment of lacI mice with a combination of tobacco smoke carcinogens, DB[a,l]P and N'-nitrosonornicotine (NNN), induces a higher fraction of mutations than expected from a simple sum of their induced individual mutation fractions, and a change in the mutational profile compared with that expected from the sum of the individual agents. The mutational profile of the combination of agents resembled that of the P53 gene in human head and neck cancers more than that of either of the individual agents, in that the percentage of the major class of mutations (GC > AT transitions) is similar to that seen in the P53 gene. A preliminary study was performed to understand the origin of the unexpected mutagenesis observations by measuring specific DNA adducts produced by both NNN and DB[a,l]P in human oral leukoplakia cells. No significant differences in the expected and observed major adduct levels from either agent were observed between individual or combined treatments, suggesting that additional adducts are important in mutagenesis induced by the mixture. Taken together, the above observations support the use of this animal model not only to investigate tobacco smoke-induced oral cancer but also to study chemoprevention.

Comparison of an HPLC-MS/MS Method with Multiple Commercial ELISA Kits on the Determination of Levels of 8-oxo-7,8-Dihydro-2'-Deoxyguanosine in Human Urine

Introduction: Analysis of 8-oxodG is usually conducted by either chromatography-based methods or by immunochemical methods commonly used based upon their low cost and high-throughput. However, concern regarding the accuracy of ELISA methods has complicated their use. We directly compare the levels of urinary 8-oxodG obtained by HPLC-MS/MS with three commercially available ELISA kits in this report. Methods: In the current study, a total of 9 human urine samples were analyzed by LC-MS/MS and three commonly used commercial available ELISA kits. Results: We found that urinary 8-oxodG levels analyzed by HPLC-MS/MS [1.4 ± 0.3 nmol/mmol creatinine) were 7.6- to 23.5-fold lower than those detected by ELISA. Overall, the correlations between ELISA and HPLC-MS/MS were poor but were improved after SPE purification for kits from ENZO (P = 0.2817 without SPE; P = 0.0086 with SPE) and Abcam (P = 0.0596 without SPE; P = 0.0473 with SPE). Discussion and conclusion: While we confirmed that SPE purification can improve the correlation between the selected ELISA kits and HPLC-MS/MS, HPLC-MS/MS is still the method of choice to accurately assess the levels of 8-oxodG in human urine.

Comparative Tumorigenicity and DNA Damage Induced by Dibenzo[ def,p]chrysene and Its Metabolites in the Mouse Ovary

Ovarian cancer ranked second in incidence among gynecologic cancers, but it causes more deaths than any other gynecologic cancer; at present there is no curative treatment beyond surgery. Animal models that employ carcinogens found in the human environment can provide a realistic platform to understand the mechanistic basis for disease development and to design rational chemopreventive/therapeutic strategies. We and others have shown that the administration of the environmental pollutant and tobacco smoke constituent dibenzo[ def,p]chrysene (DBP) to mice by several routes of exposure can induce tumors in multiple sites including the ovary. In the present study we compared, for the first time, the tumorigenicity and DNA damage induced by DBP and its metabolites DBP-dihydrodiol (DBPDHD) and DBP-dihydrodiol epoxide (DBPDE) in the mouse ovary. Compounds were dissolved in dimethyl sulfoxide (DMSO) as the vehicle and administered by topical application into the mouse oral cavity three times per week for 38 weeks. No tumors were observed in mice treated with DMSO. At equal dose (24 nmol/30 μL DMSO), the incidence of ovarian tumors induced by DBPDHD was higher (60.7%), although not significantly, than that induced by DBP (44.8%). Similarly the levels of DNA damage induced by DBPDHD in the ovary were higher than those observed with DBP. We did not observe any histological abnormality in the ovary of mice treated with DBPDE, which is consistent with lack of DNA damage. Our results suggested that both DBP and DBPDHD can be metabolized in the mouse ovary leading to the formation of DBPDE that can damage DNA, which is a prerequisite step in the initiation stage of carcinogenesis.

Effects of Black Raspberry on Dibenzo[a,l]Pyrene Diol Epoxide Induced DNA Adducts, Mutagenesis, and Tumorigenesis in the Mouse Oral Cavity

We previously showed that metabolic activation of the environmental and tobacco smoke constituent dibenzo[a,l]pyrene (DB[a,l]P) to its active fjord region diol epoxide (DB[a,l]PDE) is required to induce DNA damage, mutagenesis, and squamous cell carcinoma (SCC) in the mouse oral cavity. In contrast to procarcinogens, which were employed previously to induce SCC, DB[a,l]PDE does not require metabolic activation to exert its biological effects, and thus, this study was initiated to examine, for the first time, whether black raspberry powder (BRB) inhibits postmetabolic processes, such as DNA damage, mutagenesis, and tumorigenesis. Prior to long-term chemoprevention studies, we initially examined the effect of BRB (5% added to AIN-93M diet) on DNA damage in B6C3F1 mice using LC/MS-MS and on mutagenesis in the lacI gene in the mouse oral cavity. We showed that BRB inhibited DB[a,l]PDE-induced DNA damage (P < 0.05) and mutagenesis (P = 0.053) in the oral cavity. Tumor incidence in the oral cavity (oral mucosa and tongue) of mice fed diet containing 5% BRB was significantly (P < 0.05) reduced from 93% to 66%. Specifically, the incidence of benign tumor was significantly (P < 0.001) reduced from 90% to 31% (62% to 28% in the oral cavity and 28% to 2% in the tongue), a nonsignificant reduction of malignant tumors from 52% to 45%. Our preclinical findings demonstrate for the first time that the chemopreventive efficacy of BRB can be extended to direct-acting carcinogens that do not require phase I enzymes and is not just limited to procarcinogens. Cancer Prev Res; 11(3); 157-64. ©2017 AACR.

Effects of Black Raspberry Extract and Berry Compounds on Repair of DNA Damage and Mutagenesis Induced by Chemical and Physical Agents in Human Oral Leukoplakia and Rat Oral Fibroblasts

Black raspberries (BRB) have been shown to inhibit carcinogenesis in a number of systems, with most studies focusing on progression. Previously we reported that an anthocyanin-enriched black raspberry extract (BE) enhanced repair of dibenzo-[a,l]-pyrene dihydrodiol (DBP-diol)-induced DNA adducts and inhibited DBP-diol and DBP-diolepoxide (DBPDE)-induced mutagenesis in a lacI rat oral fibroblast cell line, suggesting a role for BRB in the inhibition of initiation of carcinogenesis. Here we extend this work to protection by BE against DNA adduct formation induced by dibenzo-[a,l]-pyrene (DBP) in a human oral leukoplakia cell line (MSK) and to a second carcinogen, UV light. Treatment of MSK cells with DBP and DBPDE led to a dose-dependent increase in DBP-DNA adducts. Treatment of MSK cells with BE after addition of DBP reduced levels of adducts relative to cells treated with DBP alone, and treatment of rat oral fibroblasts with BE after addition of DBPDE inhibited mutagenesis. These observations showed that BE affected repair of DNA adducts and not metabolism of DBP. As a proof of principle we also tested aglycones of two anthocyanins commonly found in berries, delphinidin chloride and pelargonidin chloride. Delphinidin chloride reduced DBP-DNA adduct levels in MSK cells, while PGA did not. These results suggested that certain anthocyanins can enhance repair of bulky DNA adducts. As DBP and its metabolites induced formation of bulky DNA adducts, we investigated the effects of BE on genotoxic effects of a second carcinogen that induces bulky DNA damage, UV light. UV irradiation produced a dose-dependent increase in cyclobutanepyrimidine dimer levels in MSK cells, and post-UV treatment with BE resulted in lower cyclobutanepyrimidine dimer levels. Post-UV treatment of the rat lacI cells with BE reduced UV-induced mutagenesis. Taken together, the results demonstrate that BE extract reduces bulky DNA damage and mutagenesis and support a role for BRB in the inhibition of initiation of carcinogenesis.

Hypomethylated Fgf3 is a potential biomarker for early detection of oral cancer in mice treated with the tobacco carcinogen dibenzo[def,p]chrysene

Genetic and epigenetic alterations observed at end stage OSCC formation could be considered as a consequence of cancer development and thus changes in normal or premalignant tissues which had been exposed to oral carcinogens such as Dibenzo[def,p]chrysene (DBP) may better serve as predictive biomarkers of disease development. Many types of DNA damage can induce epigenetic changes which can occur early and in the absence of evident morphological abnormalities. Therefore we used ERRBS to generate genome-scale, single-base resolution DNA methylomes from histologically normal oral tissues of mice treated with DBP under experimental conditions known to induce maximum DNA damage which is essential for the development of OSCC induced by DBP in mice. After genome-wide correction, 30 and 48 differentially methylated sites (DMS) were identified between vehicle control and DBP treated mice using 25% and 10% differences in methylation, respectively. RT-PCR was further performed to examine the expressions of nine selected genes. Among them, Fgf3, a gene frequently amplified in head and neck cancer, showed most prominent and significant gene expression change (2.4× increases), despite the hypomethylation of Fgf3 was identified at >10kb upstream of transcription start site. No difference was observed in protein expression between normal oral tissues treated with DBP or vehicle as examined by immunohistochemistry. Collectively, our results indicate that Fgf3 hypomethylation and gene overexpression, but not protein expression, occurred in the early stage of oral carcinogenesis induced by DBP. Thus, Fgf3 hypomethylation may serve as a potential biomarker for early detection of OSCC.

Effects of chronic alcohol consumption on DNA damage and immune regulation induced by the environmental pollutant dibenzo[a,l]pyrene in oral tissues of mice

Previously, we showed that oral application of the environmental pollutant dibenzo[a,l]pyrene (DB[a,l]P) induces oral tumors in mice. Thus, in the present investigation we examined the effect of alcohol on DB[a,l]P-induced DNA damage and immune regulation; we showed that alcohol (6.4% v/v in the diet, 35% of Calories) significantly enhanced the levels of (-)-anti-trans-DB[a,l]P-dA while decreased the levels of GSH in the mouse oral tissues. Analysis of RNA expression revealed that DB[a,l]P alone upregulates inflammatory genes while alcohol suppresses several markers of immune surveillance. Collectively, these results suggest that alcohol may enhance oral carcinogenesis induced by DB[a,l]P.

Abstract 503: Enhanced repair of bulky DNA adducts induced by a tobacco carcinogen and UV light in human oral epithelial cells by black raspberry extract

We were the first to report that an anthocyanin-enriched black raspberry extract (BE) inhibited mutagenesis, and reduced levels of DNA adducts induced by metabolites of the tobacco carcinogen dibenzo(a,l)pyrene (DBP), in a rat oral fibroblast cell line, by enhancing removal of DNA adducts (Guttenplan, et al., Cancer Prev Res; 9(8) August 2016). Here we extend these findings to the repair of DBP-induced DNA damage in a human oral leukoplakia cell line (MSK leuk1), and a reduction in the toxicity (assayed by dead cell numbers and cell survival) of DBP diolepoxide (DBPDE) in these cells. In addition, we examined the effect of BE on DNA damage and toxicity induced by UV light. Treatment of the MSK cells with DBP, and 2 of its metabolites, DBP-dihydrodiol and DBPDE led to a major adenine adduct, (-)-anti-trans-DB[a,l]PDE-dA (DBPDE-dA). The order of potency was DBPDE&gt;DBP&gt;DBP-dihydrodiol with one µM DBP, producing adduct levels of about 20/10E6 dA. BE in the range of 75-150 µg/ml significantly inhibited adduct formation when cells were pretreated with BE before addition of DBP. However, when cells were first treated with DBP and one day later BE was added, adduct levels were reduced by about 50% two days after treatment with DBP, indicating that the BE was enhancing DNA repair. This conclusion results from the fact that BE was not present during the metabolic activation of DBP to DBPDE, and hence couldn’t modulate the activation steps. We also tested whether BE, added 4 hr after treatment with the short-lived DBPDE, inhibited toxicity to MSK cells. Initial toxicity was measured by counting the numbers of dead cells in the medium 24 hr after addition of DBPDE; and the relative levels of surviving cells were determined using an MTT cell viability assay. It was found that 100ug/ml BE reduced toxicity induced by 25 - 200 nM DBPDE by about 50%, with a concomitant increase in survival in the BE-treated cells. As DBP produces bulky DNA adducts we also investigated the effects of BE on toxicity and levels of DNA adducts produced by UV light. Cells were irradiated for 30 - 120 seconds with 254 nm light and 15 minutes later, treated with 50 - 150 µg/ml BE. Toxicity was measured, as above, and a logarithmic decrease in cell death was observed with increasing concentration of BE. Similar to results with DBPDE, BE increased cell survival. The effects of BE on relative levels of the UV-light-induced cyclopyrimidine adducts were also determined, using an ELISA assay. BE at levels of 150 - 300 µg/ml reduced adduct levels by 30 - 60%. These results indicate that BE may provide chemopreventive effects on initiation of carcinogenesis by environmental agents that produce bulky DNA adducts - by enhancing DNA repair, likely via the nucleotide-excision repair pathway. Supported by NIH grant #CA173465.

Note: This abstract was not presented at the meeting.

Citation Format: Joseph B. Guttenplan, Kun-Ming Chen, Yuan-Wan Sun, Ross Teicher, Wieslawa Kosinska, Krishne Gowda, Shantu Amin, Gary D. Stoner, Karam El-Bayoumy. Enhanced repair of bulky DNA adducts induced by a tobacco carcinogen and UV light in human oral epithelial cells by black raspberry extract [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 503. doi:10.1158/1538-7445.AM2017-503

Selecting stage ypT0-1N0 for locally advanced rectal cancer following preoperative chemoradiotherapy: implications for potential candidates of organ-sparing management

AIM

Local excision or a wait-and-see policy may offer the possibility of organ preservation for locally advanced rectal cancer (LARC) after preoperative chemoradiotherapy (CRT). Identifying associated factors of good responders (GR) with stage ypT0-1N0 would probably influence the selection of potential candidates who were theoretically eligible for organ-sparing management. This study was to establish a scoring system to select stage ypT0-1N0 for LARC following preoperative CRT.

METHOD

Between 2009 and 2014, 262 patients with middle and low LARC were treated with CRT and radical surgery. Clinicopathological data which were found to be significantly associated with GR were incorporated into a scoring system.

RESULTS

Fifty-seven (21.8%) patients were GR with stage ypT0-1N0 in the operative specimen. Multivariate analyses indicated that a low level of pretreatment carcinoembryonic antigen (CEA) and post-treatment CEA <2.55 ng/ml (P = 0.008 and P = 0.009 respectively) and long-axis diameter of residual tumours (P = 0.006) were independently associated with stage ypT0-1N0. The three factors were incorporated into a scoring system. Using receiver operating characteristic curve analysis, we determined a cutoff value of -0.3 for scores, at which the system's sensitivity was 71.9% and specificity 73.1%. When applied to testing samples, the sensitivity was 74.1% and specificity 76.2%.

CONCLUSION

We demonstrated that low levels of pretreatment and post-treatment CEA and the long-axis diameter of residual tumours were associated with stage ypT0-1N0 for LARC after CRT. Therefore, the three-factor scoring system may be used to select potential candidates for organ-sparing management.

Upgrade of Langmuir probe diagnostic in ITER-like tungsten mono-block divertor on experimental advanced superconducting tokamak

In order to withstand rapid increase in particle and power impact onto the divertor and demonstrate the feasibility of the ITER design under long pulse operation, the upper divertor of the EAST tokamak has been upgraded to actively water-cooled, ITER-like tungsten mono-block structure since the 2014 campaign, which is the first attempt for ITER on the tokamak devices. Therefore, a new divertor Langmuir probe diagnostic system (DivLP) was designed and successfully upgraded on the tungsten divertor to obtain the plasma parameters in the divertor region such as electron temperature, electron density, particle and heat fluxes. More specifically, two identical triple probe arrays have been installed at two ports of different toroidal positions (112.5-deg separated toroidally), which can provide fundamental data to study the toroidal asymmetry of divertor power deposition and related 3-dimension (3D) physics, as induced by resonant magnetic perturbations, lower hybrid wave, and so on. The shape of graphite tip and fixed structure of the probe are designed according to the structure of the upper tungsten divertor. The ceramic support, small graphite tip, and proper connector installed make it possible to be successfully installed in the very narrow interval between the cassette body and tungsten mono-block, i.e., 13.5 mm. It was demonstrated during the 2014 and 2015 commissioning campaigns that the newly upgraded divertor Langmuir probe diagnostic system is successful. Representative experimental data are given and discussed for the DivLP measurements, then proving its availability and reliability.

Abstract 4454: Genome-wide analysis of DNA methylation induced by environmental carcinogen dibenzo[def,p]chrysene in ovarian tissues of mice

We and others have demonstrated that the administration of dibenzo[def,p]chrysene [also known as dibenzo[a,l]pyrene (DBP)], a representative example of the class of polycyclic aromatic hydrocarbon (PAH), by ip, oral gavage, or topical application onto the oral cavity induced tumors in multiple organ sites in mice; the ovary was the most susceptible tissue. We further demonstrated that the capacity of the target organs to metabolize DBP to active intermediates that can form DNA adducts may account for its tissue selective tumorigenicity. In addition, formation of DNA adducts by certain chemical carcinogens has been linked to aberrant DNA methylation, including the most extensively studied prototype PAH benzo[a]pyrene (B[a]P). The goal of this study is to examine whether alteration of DNA methylation occurs in the ovarian tissues of mice treated with DBP during the early stage of tumor development. In this study, we employed a previously established animal protocol in which the levels of DBP-DNA adducts as a function of time had been determined in the ovary following the oral administration of DBP (24 nmol, 3×/week for 5 weeks) or vehicle (DMSO) to female B6C3F1 mice (six weeks old, n = 3/group). DNA was isolated from ovary and subjected to enhanced reduced representation bisulfite sequencing (ERRBS) which is a single nucleotide resolution technique used to study DNA methylation in CpG sites and the surrounding regions. Briefly, DNA was digested by MspI followed by end repair, adenylation and adapter ligation with a modification of bead size selection to capture MspI fragments of 70-320 bp size. The resulting libraries were bisulfite-converted followed by PCR amplification and read by 1×50 bp on HiSeq 2500. Base calls of bisulfite treated sequencing reads were mapped to the mm9 mouse assembly and methylation calls were performed using Bismark v0.10.1 (Babraham Bioinformatcis, UK). The methylKit v0.9.2 R package was then used to calculate the differential methylation. Differentially methylated bases with q-value &lt; 0.01 and percent methylation difference &gt; 25% were extracted. Among 179 differentiated methylation sites (DMS) identified between DBP and vehicle-treated mice, 68 are hypermethylated and 111 are hypomethylated. About 25% of DMS are located in promoter or exon, 32% in intron and 44% in intergenic regions. DMS are located in genes including oocyte specific homeobox 2, transforming growth factor alpha, and tumor necrosis factor. Ingenuity Pathways analysis of the genes with altered methylation patterns identified top canonical pathways as growth hormone signaling, spermine biosynthesis, threonine degradation, trehalose degradation and L-serine degradation. Collectively, our previous results together with those presented here demonstrate that both genetic and epigenetic alterations may account for the carcinogenicity of DBP in the mouse ovary. Support: NIEHS R21ES020411 and NCI R01-CA173465.

Citation Format: Yuan-Wan Sun, Karam El-Bayoumy, Yuka Imamura Kawasawa, Anna Salzberg, Cesar Aliaga, Krishnegowda Gowdahalli, Shantu Amin, Kun-Ming Chen. Genome-wide analysis of DNA methylation induced by environmental carcinogen dibenzo[def,p]chrysene in ovarian tissues of mice. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4454.

Abstract 4063: Effects of electronic cigarettes (E-cigs) and hookah on the metabolic activation of the tobacco carcinogen, benzo(a)pyrene (BaP), and cellular proliferation in human oral leukoplakia cells

The possible carcinogenic effects of E-cigs on the oral cavity are uncertain because their recent availability and usage precludes long-term epidemiological studies. Also of concern is the use of hookah, which has recently increased in popularity. In addition, many, E-cig and hookah users are tobacco smokers or individuals trying to quit or cut down on smoking. Such individuals likely have precancerous cells and/or lesions in the oral cavity, as do former smokers or oral cancer survivors. The use of E-cigs and hookah then, may affect the initiation and promotion/progression stages of carcinogenesis, and be of particular concern to dual users. Here we have investigated the effects of E-cigs and to a lesser extent, hookah on the metabolism of BaP to its ultimate carcinogenic metabolite, BaP diol-epoxide (BPDE), and also the effects of E-cigs on proliferation, and expression of proliferation-related genes in leukoplakia cells. Tobacco-flavored E-cigs, and hookah were prepared from local products using a mechanical smoking device to simulated smoking, and the resulting vapor collected in a liquid N2-cooled trap to generate E-cig or hookah vapor condensates (VC). To determine the effects of E-cigs and hookah on BaP metabolism, cells from a leukoplakia-derived cell line, MSKLeuk1, were pretreated for 16 hr with E-cig or hookah VC at levels yielding nicotine concentrations of 0.5 - 8 uM (similar to plasma nicotine levels in smokers) and then treated with one uM BaP. After 8 hr the concentrations of BaP-tetrols released into the medium were measured using HPLC. BPDE hydrolyzes into BP tetrols, and their concentration serves as a surrogate for BPDE concentration. Cells pretreated with a tobacco smoke extract (TSE) from the reference cigarette, 2R4F, were included, as were untreated cells. Pretreatment with E-cig or hookah VC increased the concentration of BaP tetrols in the cell medium from 22 to 165 and 64 pM, resp. at the highest dose of each. For comparison, pretreatment with TSE at a nicotine level of 4uM increased the concentration BaP tetrols to 252 pM. The effects E-cigs on cell proliferation were assayed using an MTT assay. The cells were plated with and without E-cig VC and 24 hr later cell proliferation was assayed. Exposure to E-cigs significantly increased the rate of cell proliferation by 61%. The increase maximized at one uM nicotine. We also monitored the effects of 2 different E-cigs on the expression of the certain proteins related to cell proliferation-related genes (PCNA and pAKT) by immunoblotting. Both E-cigs increased the levels of these proteins to various extents. Our results demonstrate, for the first time, that E-cig or hookah VC enhanced metabolism of BaP to its ultimate carcinogen, and E-cig VC stimulated cellular proliferation. These results suggest that “vaping”, or hookah usage may contribute to oral cancer risk. (Support: CA173465).

Citation Format: Joseph B. Guttenplan, Yuan-Wan Sun, Kun-Ming Chen, Wieslawa Kosinska, Karam El-Bayoumy. Effects of electronic cigarettes (E-cigs) and hookah on the metabolic activation of the tobacco carcinogen, benzo(a)pyrene (BaP), and cellular proliferation in human oral leukoplakia cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4063.

Effects of Black Raspberry Extract and Protocatechuic Acid on Carcinogen-DNA Adducts and Mutagenesis, and Oxidative Stress in Rat and Human Oral Cells

Effects of black raspberry (BRB) extract and protocatechuic acid (PCA) on DNA adduct formation and mutagenesis induced by metabolites of dibenzo[a,l]pyrene (DBP) were investigated in rat oral fibroblasts. The DBP metabolites, (±)-anti-11,12-dihydroxy-11,12,-dihydrodibenzo[a,l]pyrene (DBP-diol) and 11,12-dihydroxy-13,14-epoxy-11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DBPDE) induced dose-dependent DNA adducts and mutations. DBPDE was considerably more potent, whereas the parent compound had no significant effect. Treatment with BRB extract (BRBE) and PCA resulted in reduced DBP-derived DNA adduct levels and reduced mutagenesis induced by DBP-diol, but only BRBE was similarly effective against (DBPDE). BRBE did not directly inactivate DBPDE, but rather induced a cellular response-enhanced DNA repair. When BRBE was added to cells 1 day after the DBP-diol, the BRBE greatly enhanced removal of DBP-derived DNA adducts. As oxidative stress can contribute to several stages of carcinogenesis, BRBE and PCA were investigated for their abilities to reduce oxidative stress in a human leukoplakia cell line by monitoring the redox indicator, 2',7'-dichlorodihydrofluorescein diacetate (H2DCF) in cellular and acellular systems. BRBE effectively inhibited the oxidation, but PCA was only minimally effective against H2DCF. These results taken together provide evidence that BRBE and PCA can inhibit initiation of carcinogenesis by polycyclic aromatic hydrocarbons; and in addition, BRBE reduces oxidative stress. Cancer Prev Res; 9(8); 704-12. ©2016 AACR.

[Effects of neoadjuvant chemoradiotherapy on the rates of sphincter preserving surgery in lower rectal cancer and analysis of their prognostic factors]

Objectives: To identify independent factors of sphincter preserving surgery, and to evaluated whether preoperative chemoradiotherapy (CRT) improves the sphincter preservation rate for lower rectal cancers. Methods: A total of 541 consecutive patients who underwent curative surgery for locally advanced rectal cancer (cT3-4Nx or cTxN+ ) within 6 cm of the anal verge with or without neoadjuvant CRT in Department of Colorectal Surgery, Union Hospital, Fujian Medical University between September 2000 and September 2013 were reviewed. Of these, 333 patients underwent surgery alone (Non-CRT group) and 208 patients also received preoperative chemoradiotherapy (CRT group). Clinical data were retrospectively reviewed to determine the factors influencing sphincter preservation, and to evaluate sphincter preservation rate according to tumor height over 1-cm intervals. The categorical variables were compared using χ² test and Fisher exact test. Continuous variables were compared using t test. Logistic regression was used to identify factors influencing sphincter preservation. A receiver operating characteristic (ROC) curve was constructed, and Youden's index was calculated to evaluate the predictive abilities of factors. Results: Multivariate analysis indicated that the independent factors influencing sphincter preservation were tumor height (OR=5.867, 95% CI: 4.155 to 8.285, P=0.000), pathological T stage (OR=0.688, 95% CI: 0.462 to 1.025, P=0.066), CRT (OR=2.088, 95% CI: 0.971 to 4.492, P=0.060) and histopathological type (OR=0.288, 95% CI: 0.136 to 0.611, P=0.001). The results of ROC analysis showed that the cut-off points for factors affecting sphincter preservation were as follows: (1) tumor height prior to CRT higher than 4.5 cm, (2) not mucinous or signet ring adenocarcinoma, (3) pathological T stage higher than T3, (4) had received preoperative CRT. In an analysis according to tumor height, the sphincter preservation rate was higher in CRT group only when tumor was located in 3.0 to 3.9 cm and 4.0 to 4.9 cm from the annal verge (3.0 to 3.9 cm, 59.4% vs. 2.8%, χ²=26.138, P=0.000; 4.0 to 4.9 cm, 76.9% vs. 37.9%, χ²=10.563, P=0.001). Conclusions: There is a large increased rate of sphincter preservation when patients meet the following conditions: (1) tumor height prior to CRT higher than 4.5 cm, (2) not mucinous or signet ring adenocarcinoma, (3)pathological T stage higher than T3, (4) had received preoperative CRT. Only when tumors are between 3 and 5 cm from the anal verge, CRT could increase the rate of anal sphincter preservation.

[Prognostic factors of postoperative incisional surgical site infections for colorectal cancer]

Objective: To explore the prognostic factors of postoperative incisional surgical site infections (I-SSI) for colorectal cancer. Methods: Clinical data of 2 385 colorectal cancer patients undergoing resection by the same surgical team in Department of Colon and Rectum Surgery, Fujian Medical University Union Hospital from January 2000 to February 2014 was analyzed retrospectively. There were 1 421 male and 964 female patients, with a mean age of (59±13) years. Univariate analysis and multivariate Logistic regression analysis were performed for independent prognostic factors of I-SSI. Results: The I-SSI occurred in 77 patients (3.23%). The results of univariate analysis showed that there were statistical differences in body mass index (t=-3.356), operation time (t=-3.609), length of incision (t=-5.492), radical operation (χ²=8.963), laparoscopic surgery (χ²=25.884), combined evisceration (χ²=6.349) and intraoperative blood infusion (χ²=4.176) between two groups (all P<0.05) . The results of multivariate Logistic regression analysis showed that independent prognostic factors of I-SSI were identified to be body mass index (OR=1.087, 95%CI: 1.023 to 1.155, P=0.007), operation time (OR=1.007, 95%CI: 1.002 to 1.012, P=0.006), preoperative chemoradiotherapy (OR=2.434, 95%CI: 1.099 to 5.393, P=0.028) and combined evisceration (OR=2.596, 95%CI: 1.060 to 6.357, P=0.037). The independent protective prognostic factor of I-SSI was identified to be the laparoscopic surgery (OR=0.386, 95%CI: 0.170 to 0.877, P=0.023). Conclusions: Body mass index, operation time, preoperative chemoradiotherapy and combined evisceration are identified to be independent prognostic factors for I-SSI. High-risk patients should receive individualized perioperative intervention. Nevertheless, the laparoscopic surgery can decrease the incidence of I-SSI.

Abstract 915: Effects of black raspberry extract (BRB) and related compounds on mutagenesis induced by metabolites of the tobacco carcinogen, dibenzo(a,l)pyrene in cultured rat oral fibroblasts; and on oxidative stress in human oral cancer cells

BRB powder, extracts and metabolites have been shown to inhibit tumorigenesis in oral and other sites in animal models. Here we examined the effects of an anthocyanin-enriched BRB extract, and protocatechuic acid (PA), a major BRB anthocyanin metabolite, on mutagenesis and DNA adduct formation by DBP-dihydrodiol, and DBP diolepoxide (DBPDE) (the proximate and ultimate carcinogenic metabolites, resp. of DBP) in lacI rat oral fibroblasts. DBP was poorly metabolized to genotoxic metabolites by the oral fibroblasts, but DBP-dihydrodiol was mutagenic and produced DNA adducts. DBP-dihydrodiol (0.5 uM) induced a mutant fraction of 14.1 +/- 3.9 mutants/10E5 pfu in the target cII gene. This was reduced in a concentration-dependent fashion to 9.1 +/- 2.4 by 0.1-1uM PA– a 35% reduction. Mutagenesis by DBP-dihydrodiol was also reduced in a concentration-dependent fashion by BRB extract and at the highest concentration (20ug/ml) mutagenesis was reduced by 68%. The major DNA adduct produced by 0.5 uM DBP-dihydrodiol was anti-DBPDE-dA, as assessed by L.C.-M.S.-M.S. Its levels were reduced from 13.7 +/- 1.2 to 7.8 +/- 1.9 adducts/10E6 dA by 3uM protocatechuic acid, and from 6.8 +/- 0.7 to 3.2 +/- 0.4 by 66 ug/ml BRB extract. The inhibitions were statistically significant. In contrast, no significant effect PA on mutagenesis by 140 nM DBPDE was observed, with mutant fractions similar to that of DBPDE (3.2 +/- 0.45 mutants/10E5 pfu) being obtained over a range of 0.1 - 1 uM PA. Similarly 10-50 ug/ml BRB extract had no effect on DBPDE-induced mutagenesis. Consistent with these results, levels of total DBPDE adducts were unchanged over a range of PA concentrations, with the high dose of 1uM PA yielding, 4.6 +/- 0.7 adducts/10E5 nucleotides and 4.5 +/- 0.9 without PA. Presumably the short halflife of DBPDE precludes detoxification, or scavenging of DBPDE. The effects of PA and BRB extract on oxidative stress in a human oral cancer cell line (SCC 1483, retromolar trigone) were also examined. The redox sensitive fluorescent probe, dihydrodichlorofluorescein diacetate (DHDCF) was added to the cells at 5uM and BRB (0.5-5 ug/ml) or PA (0.02-0.2 uM) was added shortly afterwards. 2 hr later all doses of BRB extract and PA inhibited the oxidation of DHDCF to its fluorescent product, in a dose-dependent manner. At 5ug/ml BRB extract the increase in fluorescence was reduced from 304 +/- 3.3 to 177 +/- 7.1 relative fluorescence units (RFU) and at 0.2 uM PA the increase was reduced to 224 +/- 25 RFU. In summary, BRB extract and PA inhibited mutagenesis and DNA adduct formation by DBP-dihydrodiol, but not DBPDE. BRB extract and PA were also effective inhibitors of oxidative stress. These mechanisms may a play a role in the protective effects of BRB on oral and other cancers in experimental animals. Supported by NIH grant #CA173465.

Citation Format: Joseph B. Guttenplan, Seungjin Kim, Ying Zhou, Wieslawa Kosinska, Ana-Vera Golgotiu, Shantu Amin, Gary D. Stoner, Yuan-Wan Sun, Kun-Ming Chen, Karam El-Bayoumy. Effects of black raspberry extract (BRB) and related compounds on mutagenesis induced by metabolites of the tobacco carcinogen, dibenzo(a,l)pyrene in cultured rat oral fibroblasts; and on oxidative stress in human oral cancer cells. [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 915. doi:10.1158/1538-7445.AM2015-915

Abstract 2955: The effects of the environmental carcinogen dibenzo[a,l]pyrene on genome-wide methylation and the impact of dietary black raspberry in mouse oral tissues

We had previously reported the carcinogenicity of dibenzo[a,l]pyrene (DB[a,l]P) in mouse oral cavity; we also found that that diets containing black raspberry (BRB) significantly reduced the levels of DNA adducts derived from DB[a,l]P in mouse oral tissues. Epigenetic alternations including DNA methylation have been shown to contribute to carcinogenesis induced by certain carcinogens. Literature data showed that dietary BRB can modulate DNA methylation at certain gene-specific promoters; however, the genome-wide methylation alterations by DB[a,l]P and the impact of BRB are not known. Therefore, to mimic the bioassay employed in our previous carcinogenicity study, B6C3F1 female mice (n = 3/group) were fed either control diet or diet containing BRB (5%) for 2 weeks prior to topical application of DMSO containing DB[a,l]P (24 nmol, 3 times a week for 5 weeks); animals treated with DMSO and control diet were used as a control group. DNA was isolated from oral tissues and subjected to enhanced reduced representation bisulfite sequencing analysis which is a single nucleotide resolution technique used to study DNA methylation in CpG sites and the surrounding regions. Briefly, DNA was digested by MspI followed by end repair, adenylation and adapter ligation with a modification of bead size selection to capture MspI fragments of 70-320 bp size. The resulting libraries were bisulfite-converted followed by PCR amplification and read by 1×50 bp on HiSeq 2500. Base calls of bisulfite treated sequencing reads were mapped to the mm9 mouse assembly and methylation calls were performed using Bismark v0.10.1. The methylKit R package was then used to calculate the differential methylation. Differentially methylated bases with q-value &lt; 0.01 and percent methylation difference &gt; 25% were extracted. Differential methylation of 30 genes was observed in DB[a,l]P compared with control; 12 genes were hypermethylated including β-catenin; hypomethylation of 18 genes was observed. Differential methylation of 960 genes was observed in mice treated with DB[a,l]P and fed BRB compared to DB[a,l]P. Ingenuity Pathways analysis was performed on each of the resulting gene sets in the three groups. Pathway analysis of the genes with altered methylation patterns identified canonical pathways for the involvement of cancer related network for genes involved in Wnt/β-catenin signaling, epithelial-mesenchymal transition (EMT), glycolysis and p53 signaling pathways in mice treated with DB[a,l]P. On the other hand, the canonical pathways identified in mice treated with DB[a,l]P and fed BRB are genes involved in glutamate receptor signaling, IGF-1 signaling, EMT, glycolysis, and protein citrullination. Using this quantitative sequencing-based approach, our work uncovers significant global DNA methylation alterations in mouse oral tissues by DB[a,l]P alone and together with BRB. Support: NCI R01-CA173465

Citation Format: Yuan-Wan Sun, Kun-Ming Chen, Yuka Imamura Kawasawa, Anna Salzberg, Cesar Aliaga, Krishnegowda Gowdahalli, Shantu Amin, Gary Stoner, Karam El-Bayoumy. The effects of the environmental carcinogen dibenzo[a,l]pyrene on genome-wide methylation and the impact of dietary black raspberry in mouse oral tissues. [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 2955. doi:10.1158/1538-7445.AM2015-2955

Brief Note Low diversity of the major histocompatibility complex class II DRA gene in domestic goats (Capra hircus) in Southern China

DRA encodes the alpha chain of the DR heterodimer, is closely linked to DRB and is considered almost monomorphic in major histocompatibility complex region. In this study, we identified the exon 2 of DRA to evaluate the immunogenetic diversity of Chinese south indigenous goat. Two single nucleotide polymorphisms in an untranslated region and one synonymous substitution in coding region were identified. These data suggest that high immunodiversity in native Chinese population.

Tissue Distribution, Excretion and Pharmacokinetics of the Environmental Pollutant Dibenzo[def,p]chrysene in Mice

Dibenzo[def,p]chrysene (DBP), a representative example of the class of polycyclic aromatic hydrocarbon (PAH), is known to induce tumors in multiple organ sites including the ovary, lung, mammary glands, and oral cavity in rodents. The goal of this study was to test the hypothesis that the levels of DBP and its metabolites that reach and retain the levels for an extended time in the target organs as well as the capacity of these organs to metabolize this carcinogen to active metabolites that can damage DNA may account for its tissue selective tumorigenicity. Therefore, we used the radiolabeled [(3)H] DBP to accurately assess the tissue distribution, excretion, and pharmacokinetics of this carcinogen. We also compared the levels of DBPDE-DNA adducts in a select target organ (ovary) and nontarget organs (kidney and liver) in mice treated orally with DBP. Our results showed that after 1 week, 91.40 ± 7.23% of the radioactivity was recovered in the feces; the corresponding value excreted in the urine was less than 2% after 1 week. After 24 h, the stomach had the highest radioactivity followed by the intestine and the liver; however, after 1 week, levels of the radioactivity in these organs were the lowest among tissues examined including the ovary and liver; the pharmacokinetic analysis of DBP was conducted using a one compartment open model. The level of (-)-anti-trans-DBPDE-dA in the ovaries (8.91 ± 0.08 adducts/10(7) dA) was significantly higher (p < 0.01) than the levels of adducts in kidneys (0.69 ± 0.09 adducts/10(7) dA) and livers (0.63 ± 0.11 adducts/10(7) dA). Collectively, the results of the tissue distribution and pharmacokinetic analysis may not fully support our hypothesis, but the capacity of the target organs vs nontarget organs to metabolize DBP to active intermediates that can damage DNA may account for its tissue selective tumorigenicity.

Abstract 230: The inhibitory effects of an anthocyanin enriched fraction of black raspberry (BRB), protocatechuic acid and ferulic acid on DB[a,l]P-induced DNA adduct formation in mouse oral tissues

Oral squamous cell carcinoma (OSCC) is the most common cancer of the head and neck region; in the USA, over 45,000 cases and about 11,000 deaths from the disease occur annually. Progress in the prevention and control of OSCC has been hampered by the lack of appropriate animal models that would reflect human exposure. Tobacco smoking is considered a major etiological factor in the development of oral cancer. Previous studies have demonstrated the ability of diets containing 5-10% freeze-dried black raspberry (BRB) powder to inhibit the development of chemically-induced cancers in multiple organ sites in rodents including 7,12-dimethylbenz(a)anthracene (DMBA) induced squamous cell carcinomas (SCC) in the hamster cheek pouch. However, DMBA is not present in the environment and the hamster cheek pouch model may not be applicable to humans. We had previously reported the carcinogenicity of dibenzo[a,l]pyrene (DB[a,l]P), an environmental pollutant and a tobacco smoke component, in mouse oral cavity. Recently, we demonstrated that administration of BRB at 5% in the diet can significantly reduce DNA adducts resulted from the administration of DB[a,l]P. It has also been shown that anthocyanins are the most abundant compounds in BRBs that can account for much of their antioxidant activity. In the current study, under identical conditions we compare the inhibitory effects of an anthocyanin enriched fraction extracted from black raspberry (BRBE), protocatechuic acid (PA, a major metabolite of anthocyanins) or ferulic acid (FA, a major phenolic acid in raspberries shown to reduce oral carcinogenesis) with BRB on DNA adducts induced by DB[a,l]P in mouse oral cavity. Levels of DB[a,l]PDE-DNA adducts were quantified by a LC-MS/MS method. We demonstrated that the administration of BRBE (1.6 %), protocatechuic acid (0.2%) or ferulic acid (0.05%) in the diet, starting 2 weeks before DB[a,l]P (24 nmol, 3 times a week for 5 weeks) significantly resulted in 29.6%, 23.0% or 25.3% reduction of the level of (-)-anti-trans-DB[a,l]PDE-dA in murine oral tissues, respectively, compared to a 19.2% reduction of BRB. Our results clearly showed that the anthocyanin components of BRB and its metabolite, PA, are responsible for the inhibitory effects of BRB on the DB[a,l]P- induced DNA adducts formation; in addition, BRB and its related components can inhibit the metabolic activation of DB[a,l]P, and may prevent the subsequent mutagenesis and carcinogenesis resulting from exposure to DB[a,l]P. Supported by NIH grant #CA173465.

Citation Format: Kun-Ming Chen, Shangmin Zhang, Yuan-Wan Sun, Cesar Aliaga, Krishnegowda Gowdahalli, Shantu Amin, Gary Stoner, Karam El-Bayoumy. The inhibitory effects of an anthocyanin enriched fraction of black raspberry (BRB), protocatechuic acid and ferulic acid on DB[a,l]P-induced DNA adduct formation in mouse oral tissues. [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 230. doi:10.1158/1538-7445.AM2014-230

Simultaneous detection of deoxyadenosine and deoxyguanosine adducts in the tongue and other oral tissues of mice treated with Dibenzo[a,l]pyrene

We were the first to demonstrate that direct application of the environmental pollutant and tobacco smoke constituent dibenzo[a,l]pyrene (DB[a,l]P) into the oral cavity of mice induced squamous cell carcinoma (SCC) in oral tissues but not in the tongue; however, the mechanisms that can account for the varied carcinogenicity remain to be determined. Furthermore, we also showed that not only dA adducts, but also dG adducts can account for the mutagenic activity of DB[a,l]P in the oral tissues in vivo. In this study, we initially focused on DB[a,l]P-induced genotoxic effects in both oral and tongue tissues. Therefore, to fully assess the contribution of these DNA adducts in the initiation stage of carcinogenesis induced by DB[a,l]P, an LC-MS/MS method to simultaneously detect and quantify DB[a,l]PDE-dG and -dA adducts was developed. Mice were orally administered with DB[a,l]P (24 nmole, 3 times per week for 5 weeks) or its fjord region diol epoxide, (±)-anti-11,12-dihydroxy-13,14-epoxy-11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE, 12 nmole, single application); animals were sacrificed at 2, 7, 14, and 28 days after the last dose of carcinogen administration. Oral and tongue tissues were obtained and DNA were isolated followed by enzymatic hydrolysis. Following the development of an isotope dilution LC-MS/MS method, we successfully detected (−)-anti-cis- and (−)-anti-trans-DB[a,l]PDE-N²-dG, as well as (−)-anti-cis- and (−)-anti-trans-DB[a,l]PDE-N⁶-dA in oral and tongue tissues of mice treated with DB[a,l]P. Levels of (−)-anti-trans-DB[a,l]PDE-N⁶-dA were ≥2 folds higher than (−)-anti-cis-DB[a,l]PDE-N⁶-dA adduct and those of dG adducts in the oral tissues and tongue at all time points selected after the cessation of DB[a,l]P treatment. Levels of dG adducts were comparable in both tissues. Collectively, our results support that DB[a,l]P is predominantly metabolized to (−)-anti-DB[a,l]PDE, and the levels and persistence of (−)-anti-trans-DB[a,l]PDE-N⁶-dA may, in part, explain the carcinogenicity of DB[a,l]P in the oral tissues but not in the tongue.

New edge coherent mode providing continuous transport in long-pulse H-mode plasmas

An electrostatic coherent mode near the electron diamagnetic frequency (20-90 kHz) is observed in the steep-gradient pedestal region of long pulse H-mode plasmas in the Experimental Advanced Superconducting Tokamak, using a newly developed dual gas-puff-imaging system and diamond-coated reciprocating probes. The mode propagates in the electron diamagnetic direction in the plasma frame with poloidal wavelength of ∼8  cm. The mode drives a significant outflow of particles and heat as measured directly with the probes, thus greatly facilitating long pulse H-mode sustainment. This mode shows the nature of dissipative trapped electron mode, as evidenced by gyrokinetic turbulence simulations.

Dispersive infrared spectroscopy measurements of atmospheric CO₂ using a Fabry-Pérot interferometer sensor

In this paper, we present the first dispersive infrared spectroscopic (DIRS) measurement of atmospheric carbon dioxide (CO2) using a new scanning Fabry-Pérot interferometer (FPI) sensor. The sensor measures the optical spectra in the mid infrared (3,900 nm to 5,220 nm) wavelength range with full width half maximum (FWHM) spectral resolution of 78.8 nm at the CO2 absorption band (~4,280 nm) and sampling resolution of 20 nm. The CO2 concentration is determined from the measured optical absorption spectra by fitting it to the CO2 reference spectrum. Interference from other major absorbers in the same wavelength range, e.g., carbon monoxide (CO) and water vapor (H2O), was taken out by including their reference spectra in the fit as well. The detailed descriptions of the instrumental setup, the retrieval procedure, a modeling study for error analysis as well as laboratory validation using standard gas concentrations are presented. An iterative algorithm to account for the non-linear response of the fit function to the absorption cross sections due to the broad instrument function was developed and tested. A modeling study of the retrieval algorithm showed that errors due to instrument noise can be considerably reduced by using the dispersive spectral information in the retrieval. The mean measurement error of the prototype DIRS CO2 measurement for 1 minute averaged data is about ±2.5 ppmv, and down to ± 0.8ppmv for 10 minute averaged data. A field test of atmospheric CO2 measurements were carried out in an urban site in Hong Kong for a month and compared to a commercial non-dispersive infrared (NDIR) CO2 analyzer. 10 minute averaged data shows good agreement between the DIRS and NDIR measurements with Pearson correlation coefficient (R) of 0.99. This new method offers an alternative approach of atmospheric CO2 measurement featuring high accuracy, correction of non-linear absorption and interference of water vapor.

Mechanisms of oral carcinogenesis induced by dibenzo[a,l]pyrene: an environmental pollutant and a tobacco smoke constituent

We previously reported that dibenzo[a,l]pyrene (DB[a,l]P), the most potent known environmental carcinogen among polycyclic aromatic hydrocarbons (PAH) congeners, is carcinogenic in the oral tissues of mice. We have now developed a new mouse model which employs the oral application of the fjord region diol epoxide, (±)-anti-11,12-dihydroxy-13,14-epoxy-11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE), a metabolite of the tobacco smoke constituent DB[a,l]P, and we show its specific induction of oral squamous cell carcinoma (OSCC) in both tongue and other oral tissues. Groups of B6C3F1 mice (20/group) received 6 or 3 nmol of (±)-anti-DB[a,l]PDE administered into the oral cavity; 3 times per week for 38 weeks. Additional groups received the vehicle alone or were left untreated. Mice were sacrificed 42 weeks after the first carcinogen administration. The high dose induced 74 and 100% OSCC in the tongue and other oral tissues, respectively; the corresponding values at the lower dose were 45 and 89%. Using immunohistochemistry, we showed that DB[a,l]PDE resulted in overexpression of p53 and COX-2 proteins in malignant tissues when compared to normal oral tissues and tongues. Consistent with the carcinogenicity, we demonstrated powerful mutagenicity in cII gene in B6C3F1 (Big Blue) mouse tongue. The mutational profile in lacI reporter gene is similar to those detected in human head and neck cancer, and p53 mutations were observed in mouse oral tumor tissues. Taken together, we conclude that the formation of diol epoxides plays a major role among the mechanisms by which DB[a,l]P exerts its oral mutagenicity and tumorigenicity.

Analysis of uncertainty in equilibrium reconstruction in the EAST superconducting tokamak

The analysis of uncertainties of magnetic measurements in equilibrium reconstruction is carried out on the EAST (Experimental Advanced Superconducting Tokamak) tokamak. It is shown that uncertainties of magnetic diagnostics are about 0.2% and 10 mWb for flux loops and 0.6% and 20 G for magnetic probes. Analyzing the sensitivity of the magnetic data uncertainty in the plasma shape reconstruction is presented, based on EFIT fixed boundary and fitting mode and applying overall uncertainty as fitting weight in EFIT. It is found that reconstruction uncertainties are ranged in 0.5-1.4 cm for 6 control segments, less than 0.8 cm for X-points, and 1.0-1.6 cm for strike points with 95% confidence, in the last experimental campaign on the EAST tokamak.

High-performance cavity-phase matching by pump reflection

Since cavity-phase matching has been experimentally realized, the efficiency is limited to 20%. In this Letter, we successfully achieved a conversion efficiency as high as 41% with a slope efficiency of 48.5% using cavity-phase matching, by reflecting the pump beam at the end surface of the KTiOPO(4) crystal. The high performance of the device makes it a promising candidate to substitute for quasi-phase-matching material.

Epidemiological characteristics of malaria in Ningbo City, China 2000-2011

The objective of this study was to explore the trend and the epidemiological characteristics of malaria in Ningbo from 2000 through 2011 and provide scientific evidence for the prevention and control. Using the retrospective study, data relating to malaria epidemics during 2000-2011 in Ningbo were collected through the questionnaires of the cases and other important surveillance data. Adult mosquitoes were collected using CDC light traps baited with CO2. Results showed that Plasmodium vivax was the main species, and Anopheles sinensis was the only vector species of malaria. The annual incidence rates (per 100000) ranged from 0.156 to 3.224, and about 95.41% of the cases were imported. The cases occurred mainly between May and November and the incidence showed two peaks, and the local transmission of malaria was determined by vector density. Considering the vast majority of these infections were imported vivax malaria cases from domestic endemic areas (particularly Anhui province), and may lead to limited local transmission, strengthening the routine monitoring of imported malaria, ensuring timely diagnosis, improving case detection rate, giving a standardized treatment to patients and intensifying public health education on malaria prevention are extremely important to malaria prevention and control activities.