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PURPOSE: This study examined targeted genomic variants of transforming growth factor beta (TGFB) signaling in Appalachian women. Appalachian women with cervical cancer were compared to healthy Appalachian counterparts to determine whether these polymorphic alleles were over-represented within this high-risk cancer population, and whether lifestyle or environmental factors modified the aggregate genetic risk in these Appalachian women. METHODS: Appalachian women’s survey data and blood samples from the Community Awareness, Resources, And Education (CARE) CARE I and CARE II studies (N=163 invasive cervical cancer cases, 842 controls) were used to assess gene-environment interactions and cancer risk. Polymorphic allele frequencies and socio-behavioral demographic measurements were compared using t-tests and chi-square tests. Multivariable logistic regression was used to evaluate interaction effects between genomic variance and demographic, behavioral, and environmental characteristics. RESULTS: Several alleles demonstrated significant interaction with smoking (TP53 rs1042522, TGFB1 rs1800469), alcohol consumption (NQO1 rs1800566), and sexual intercourse before the age of 18 (TGFBR1 rs11466445, TGFBR1 rs7034462, TGFBR1 rs11568785). Interestingly, we noted a significant interaction between “Appalachian self-identity” variables and NQO1 rs1800566. Multivariable logistic regression of cancer status in an over-dominant TGFB1 rs1800469/TFBR1 rs11568785 model demonstrated a 3.03-fold reduction in cervical cancer odds. Similar decreased odds (2.78-fold) were observed in an over-dominant TGFB1 rs1800469/TGFBR1 rs7034462 model in subjects who had no sexual intercourse before age 18. CONCLUSIONS: This study reports novel associations between common low-penetrance alleles in the TGFB signaling cascade and modified risk of cervical cancer in Appalachian women. Furthermore, our unexpected findings associating Appalachian identity and NQO1 rs1800566 suggests that the complex environmental exposures that contribute to Appalachian self-identity in Appalachian cervical cancer patients represents an emerging avenue of scientific exploration.

Oral cancer accounts for about 50,000 new cases and 10,000 new deaths in the U.S. every year. This amounts to about one person every hour every day. To combat this public health challenge, there is a need to identify agents that prevent oral cancer development and fully characterize their mechanisms of action. Preclinical and clinical studies demonstrate the ability of black raspberries (BRBs) to inhibit oral carcinogenesis. We recently showed that in an experimental model of rat oral carcinogenesis using the carcinogen 4 nitroquinoline-1-oxide (4NQO), BRBs reduce oral lesion incidence and multiplicity. However, understanding how the bioactive compounds in BRBs drive the metabolic and molecular pathways that lead to oral cancer chemoprevention remains unclear. In this study, we determined the potential metabolic and molecular mechanisms associated with BRB-mediated chemoprevention of oral carcinogenesis using the well-established carcinogen-induced rat oral cancer model. Male F344 rats were divided into 4 groups: sentinel group, 4NQO only group, 4NQO + 5% BRB group, and 4NQO + 10% BRB group. 4NQO was administered in drinking water (20ug/mL) for 10 weeks after which regular drinking water was provided for 6 weeks. BRBs were incorporated into rat diets at 5% or 10% concentrations and fed to the rat treatment groups for the last 6 weeks after 4NQO administration. Sentinel animals did not receive 4NQO or BRB. At terminal sacrifice, urine samples from all groups were harvested and analyzed by NMR-based metabolomics. We identified metabolites in rat urine samples by "Complex Mixture Analysis by NMR" (COLMAR) followed by 2D 13C-1H HSQC NMR quantitative analysis. RNA was extracted from rat tongue samples and used for RNA sequencing analysis. 4NQO only administered rats showed highest overall intensity, which was about 2.5 times higher than 4NQO + BRB treated rats. 171 metabolites were identified in urine samples of 4NQO only administered rats while 101 and 90 metabolites were identified in 4NQO administered rats that were treated with 10% and 5% BRB, respectively. About 31 "unique" metabolites were identified in 4NQO only administered rat urine samples but were absent in BRB treated groups. Fourteen additional metabolites were increased and 11 metabolites were decreased following BRB treatment of 4NQO administered rats compared to rats administered with 4NQO only. Our metabolomic and transcriptomic analyses reveal distinct molecular and metabolic markers and pathways that drive oral carcinogenesis and BRB-mediated oral chemoprevention, which can potentially be exploited in oral cancer treatment strategies. Citation Format: Steve Oghumu, Thomas J. Knobloch, Logan C. Weghorst, Lei Bruschweiler-Li, Cheng Wang, Rafael Bruschweiler, Christopher M. Weghorst. Potential metabolic and molecular mechanisms of black raspberry-mediated oral cancer chemoprevention [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1270.

It is expected that in 2016, there will be an estimated 48,330 new cases and 9,570 deaths due to oral cancer in the US, which is about one person every hour every day. Due to the epithelial field defects associated with oral carcinogenesis, tumor recurrence and second primary tumor incidence are common. Recently conducted Phase I Clinical trials demonstrate the ability of black raspberries (BRBs) to modulate inflammatory biomarkers of molecular efficacy that supports a chemopreventive strategy against oral cancer. From these human trials we have established a molecular signature of BRB responsive biomarkers. However, it is essential that a preclinical animal model of BRB chemoprevention which recapitulates the fundamental features of human oral carcinogenesis be developed, so that we can evaluate potential mechanisms of action and validate molecular biomarkers of BRB efficacy. We therefore established the ability of BRB to inhibit oral lesion formation in a rat model of 4-nitroquinoline 1-oxide (4NQO) induced oral carcinogenesis and examined molecular efficacy using a clinically relevant transcriptional signature. Oral cancer was induced in F344 rats using 4NQO in drinking water for 10 weeks followed by regular drinking water for 16 weeks. Rats were administered a diet containing 5 or 10 percent lyophilized BRBs. Tongue tissues were examined for lesion multiplicity, incidence and histopathological features. Clinically derived pro-inflammatory and pro-survival molecular biomarkers were also determined by real-time PCR and ELISA. Dietary administration of 5 and 10 percent BRBs reduced combined lesion incidence and multiplicity by -39.3% and -28.6% respectively. Histopathological analyses of tongue sections further demonstrate the chemopreventive ability of dietary BRB administration in the rat model. Pro-survival and pro-inflammatory biomarkers were downregulated in BRB administered 4NQO induced rats compared to untreated 4NQO induced rats. Our study shows that dietary administration of BRB inhibits oral carcinogenesis in the rat 4NQO model. The rat 4NQO model is suitable for interrogating mechanisms of action of BRB-mediated oral cancer chemoprevention. Citation Format: Steve Oghumu, Thomas Knobloch, Jennifer Ahn-Jarvis, Logan Weghorst, Kyle Horvath, Paul Geuy, Christopher Weghorst. Chemoprevention of rat oral carcinogenesis by black raspberry phytochemicals [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 5264. doi:10.1158/1538-7445.AM2017-5264