Phenolic acids prevent sex-steroid deficiency-induced bone loss and bone marrow adipogenesis in mice

Phenolic acids, such as hippuric acid (HA) and 3-(3-hydroxyphenyl) propionic acid (3-3-PPA), can be produced from microbiome digestion of polyphenols. Previously it was found that HA and 3-3-PPA facilitate bone formation and suppress bone resorption. However, the mechanism of action by which HA and 3-3-PPA protect bone from degeneration is currently unknown. In this report, we present that HA and 3-3-PPA suppression of bone resorption is able to ameliorate bone loss in an ovariectomy (OVX) osteopenic mouse model though not to the extent of Zoledronic acid (ZA). HA and 3-3-PPA treatments were shown to significantly decrease bone marrow adipocyte-like cell formation and inhibited gene expression of key adipogenesis regulator peroxisome proliferator activated receptor gamma (PPARγ) and lipoprotein lipase (Lpl) in bone from OVX mice. In addition, ChIP experiments showed that the association between PPARγ and Lpl promoter region in preadipocyte-like cells was significantly suppressed following HA or 3-3-PPA treatment. Contrasting HA and 3-3-PPA, ZA significantly increased TRAP activity in the area close to growth plate and significantly suppressed bone cell proliferation. These data suggest that phenolics acids such as HA or 3-3-PPA may prevent bone degeneration after OVX through suppression of inflammatory milieu in the bone.

Genetic ancestry and radical prostatectomy findings in Hispanic/Latino patients

Background

African ancestry is a known factor associated with the presentation and aggressiveness of prostate cancer (PC). Hispanic/Latino populations exhibit varying degrees of genetic admixture across Latin American countries, leading to diverse levels of African ancestry. However, it remains unclear whether genetic ancestry plays a role in the aggressiveness of PC in Hispanic/Latino patients. We explored the associations between genetic ancestry and the clinicopathological data in Hispanic/Latino PC patients from Colombia.

Patients and methods

We estimated the European, Indigenous and African genetic ancestry, of 230 Colombian patients with localized/regionally advanced PC through a validated panel for genotypification of 106 Ancestry Informative Markers. We examined the associations of the genetic ancestry components with the Gleason Grade Groups (GG) and the clinicopathological characteristics.

Results

No association was observed between the genetic ancestry with the biochemical recurrence or Gleason GG; however, in a two groups comparison, there were statistically significant differences between GG3 and GG4/GG5 for European ancestry, with a higher mean ancestry proportion in GG4/GG5. A lower risk of being diagnosed at an advanced age was observed for patients with high African ancestry than those with low African ancestry patients (OR: 0.96, CI: 0.92-0.99, p=0.03).

Conclusion

Our findings revealed an increased risk of presentation of PC at an earlier age in patients with higher African ancestry compared to patients with lower African ancestry in our Hispanic/Latino patients.

Maternal Western diet programs cardiometabolic dysfunction and hypothalamic inflammation via epigenetic mechanisms predominantly in the male offspring

OBJECTIVE

Maternal exposure during pregnancy is a strong determinant of offspring health outcomes. Such exposure induces changes in the offspring epigenome resulting in gene expression and functional changes. In this study, we investigated the effect of maternal Western hypercaloric diet (HCD) programming during the perinatal period on neuronal plasticity and cardiometabolic health in adult offspring.

METHODS

C57BL/6J dams were fed HCD for 1 month prior to mating with regular diet (RD) sires and kept on the same diet throughout pregnancy and lactation. At weaning, offspring were maintained on either HCD or RD for 3 months resulting in 4 treatment groups that underwent cardiometabolic assessments. DNA and RNA were extracted from the hypothalamus to perform whole genome methylation, mRNA, and miRNA sequencing followed by bioinformatic analyses.

RESULTS

Maternal programming resulted in male-specific hypertension and hyperglycemia, with both males and females showing increased sympathetic tone to the vasculature. Surprisingly, programmed male offspring fed HCD in adulthood exhibited lower glucose levels, less insulin resistance, and leptin levels compared to non-programmed HCD-fed male mice. Hypothalamic genes involved in inflammation and type 2 diabetes were targeted by differentially expressed miRNA, while genes involved in glial and astrocytic differentiation were differentially methylated in programmed male offspring. These data were supported by our findings of astrogliosis, microgliosis and increased microglial activation in programmed males in the paraventricular nucleus (PVN). Programming induced a protective effect in male mice fed HCD in adulthood, resulting in lower protein levels of hypothalamic TGFβ2, NF-κB2, NF-κBp65, Ser-pIRS1, and GLP1R compared to non-programmed HCD-fed males. Although TGFβ2 was upregulated in male mice exposed to HCD pre- or post-natally, only blockade of the brain TGFβ receptor in RD-HCD mice improved glucose tolerance and a trend to weight loss.

CONCLUSIONS

Our study shows that maternal HCD programs neuronal plasticity in the offspring and results in male-specific hypertension and hyperglycemia associated with hypothalamic inflammation in mechanisms and pathways distinct from post-natal HCD exposure. Together, our data unmask a compensatory role of HCD programming, likely via priming of metabolic pathways to handle excess nutrients in a more efficient way.

Tumor infiltrating lymphocytes (TILs) are a prognosis biomarker in Colombian patients with triple negative breast cancer

Triple negative breast cancer (TNBC) is highly immunogenic and high levels of tumor infiltrating lymphocytes (TILs) have been associated with a better prognosis and higher probability to achieve pathological complete response. Here, we explore the potential role of stromal TILs level and composition as a prognostic and predictive biomarker in TNBC. 195 Tumor biospecimens from patients diagnosed with TNBC were included. Stromal TILs (sTILs), positive CD4/CD8 cells were evaluated. Differences in clinic-pathological characteristics according to immune infiltration were assessed. The predictive and prognostic value of immune infiltration was analyzed by multivariate models. Higher immune infiltration was observed in patients with favorable clinical-pathological features. Survival analysis showed that longer overall survival times were observed in patients with a higher infiltration of sTILs (p = 0.00043), CD4 + (p = 0.0074) and CD8 + (p = 0.008). In the multivariate analysis, low levels of sTILs were found to be associated with a higher mortality hazard (HR: 1.59, 95% CI 1.01-2.48). CD4 and CD8 immune infiltration were associated with higher odds for pathological complete response (OR: 1.20, 95% CI 1.00-1.46, OR: 1.28, 1.02-1.65, respectively). Our results suggest that immune infiltration could be used as a prognostic marker for overall survival in TNBC patients.

Sulindac sulfide as a non-immune suppressive γ-secretase modulator to target triple-negative breast cancer

Introduction

Triple-negative breast cancer (TNBC) comprises a heterogeneous group of clinically aggressive tumors with high risk of recurrence and metastasis. Current pharmacological treatment options remain largely limited to chemotherapy. Despite promising results, the efficacy of immunotherapy and chemo-immunotherapy in TNBC remains limited. There is strong evidence supporting the involvement of Notch signaling in TNBC progression. Expression of Notch1 and its ligand Jagged1 correlate with poor prognosis. Notch inhibitors, including g-secretase inhibitors (GSIs), are quite effective in preclinical models of TNBC. However, the success of GSIs in clinical trials has been limited by their intestinal toxicity and potential for adverse immunological effects, since Notch plays key roles in T-cell activation, including CD8 T-cells in tumors. Our overarching goal is to replace GSIs with agents that lack their systemic toxicity and ideally, do not affect tumor immunity. We identified sulindac sulfide (SS), the active metabolite of FDA-approved NSAID sulindac, as a potential candidate to replace GSIs.

Methods

We investigated the pharmacological and immunotherapeutic properties of SS in TNBC models in vitro, ex-vivo and in vivo.

Results

We confirmed that SS, a known γ-secretase modulator (GSM), inhibits Notch1 cleavage in TNBC cells. SS significantly inhibited mammosphere growth in all human and murine TNBC models tested. In a transplantable mouse TNBC tumor model (C0321), SS had remarkable single-agent anti-tumor activity and eliminated Notch1 protein expression in tumors. Importantly, SS did not inhibit Notch cleavage in T- cells, and the anti-tumor effects of SS were significantly enhanced when combined with a-PD1 immunotherapy in our TNBC organoids and in vivo.

Discussion

Our data support further investigation of SS for the treatment of TNBC, in conjunction with chemo- or -chemo-immunotherapy. Repurposing an FDA-approved, safe agent for the treatment of TNBC may be a cost-effective, rapidly deployable therapeutic option for a patient population in need of more effective therapies.

The Efficacy of CB-103, a First-in-Class Transcriptional Notch Inhibitor, in Preclinical Models of Breast Cancer

BACKGROUND

The efficacy of CB-103 was evaluated in preclinical models of both ER+ and TNBC. Furthermore, the therapeutic efficacy of combining CB-103 with fulvestrant in ER+ BC and paclitaxel in TNBC was determined.

METHODS

CB-103 was screened in combination with a panel of anti-neoplastic drugs. We evaluated the anti-tumor activity of CB-103 with fulvestrant in ESR1-mutant (Y537S), endocrine-resistant BC xenografts. In the same model, we examined anti-CSC activity in mammosphere formation assays for CB-103 alone or in combination with fulvestrant or palbociclib. We also evaluated the effect of CB-103 plus paclitaxel on primary tumors and CSC in a GSI-resistant TNBC model HCC1187. Comparisons between groups were performed with a two-sided unpaired Students' t-test. A one-way or two-way ANOVA followed by Tukey's post-analysis was performed to analyze the in vivo efficacy study results.

THE RESULTS

CB-103 showed synergism with fulvestrant in ER+ cells and paclitaxel in TNBC cells. CB-103 combined with fulvestrant or paclitaxel potently inhibited mammosphere formation in both models. Combination of CB-103 and fulvestrant significantly reduced tumor volume in an ESR1-mutant, the endocrine-resistant BC model. In a GSI-resistant TNBC model, CB-103 plus paclitaxel significantly delayed tumor growth compared to paclitaxel alone.

CONCLUSION

our data indicate that CB-103 is an attractive candidate for clinical investigation in endocrine-resistant, recurrent breast cancers with biomarker-confirmed Notch activity in combination with SERDs and/or CDKis and in TNBCs with biomarker-confirmed Notch activity in combination with taxane-containing chemotherapy regimens.

miRNAs signature as potential biomarkers for cervical precancerous lesions in human papillomavirus positive women

Biomarkers to identify women at risk of cervical cancer among those with high-risk HPV infection (hrHPV+) are needed. Deregulated expression of microRNAs (miRNAs) contributes to hrHPV-induced cervical carcinogenesis. We aimed at identifying miRNAs with the capacity to distinguish high (CIN2+) and low (≤ CIN1) grade cervical lesions. We sequenced miRNA libraries from Formalin-Fixed Paraffin-Embedded (FFPE) tissues from women with CIN2+ (n = 10) and age-matched women with ≤ CIN1 (n = 10), randomly and retrospectively selected from a trial that followed women for 24 months after a hrHPV+ test at the screening visit. Five miRNAs differentially expressed were validated by RT-qPCR in an independent set of FFPE tissues with a reviewed diagnosis of CIN2+ (n = 105) and ≤ CIN1 (n = 105). The Ingenuity Pathway Analysis (IPA) was conducted to identify mRNAs inversely correlated with the top 25 differentially expressed miRNAs. Inverse correlations with 401 unique mRNA targets were identified for fourteen of the top 25 differentially expressed miRNAs. Eleven of these miRNAs targeted 26 proteins of pathways deregulated by HPV E6 and E7 oncoproteins and two of them, miR-143-5p and miR-29a-3p, predicted CIN2+ and CIN3+ in the independent validation by RT-qPCR of FFPE tissues from hrHPV-positive women.

Abstract 5237: Regulation of genes located in 6q25 by an Indigenous American genetic variant in breast cancer patients from Peru

Genetic studies in women of Hispanic/Latina origin identified a single nucleotide polymorphism (SNP) in the 6q25 region, rs140068132, that correlates with Indigenous American (IA) ancestry and is protective against BC. The underrepresentation of Latin American populations in public databases has hindered the study of the mechanisms by which this SNP confers a protective effect. We aimed to identify IA germline variants associated with BC risk and to test their association with tumor gene expression in this region.

We performed a case-control fine-mapping analysis in the 6q25 region. BC patients part of the PEGEN-BC Study (N=1809) were included as cases and women from a pregnancy outcomes study in Peru as controls (N=3334). Genome-wide genotype data were available and missing genotypes were imputed using the TOPMED Imputation Server. Logistic regression was used to test the association between each SNP and BC risk. We exome-sequenced 247 breast tumors of PEGEN-BC patients. Tumor subtype was assigned by the pam50 method. We excluded patients diagnosed with stage IV disease, with tumors classified as normal-like or as uncertain, and carriers of the GG genotype for rs140068132, leaving 242 samples. Association between rs140068132 and gene expression of genes in the 6q25 region was tested adjusting by age at diagnosis and IA ancestry.

The strongest signal corresponded to rs140068132 (odds ratio (OR)=0.53, p=1.9e-21). The model adjusted by rs140068132 revealed three additional independent variants that correlate with Indigenous American ancestry: rs184135739 (OR=0.8, p=0.006), rs141057867 (OR=0.87, p=0.006) and rs140125124 (OR=1.23, p=0.015). Gene expression analysis stratified by subtype revealed that among HER2+ tumors (N=63), rs140068132 was associated with ARMT1 (fold change comparing AA to AG (FC)=1.6, p<0.01), CCDC170 (FC=1.8, p<0.01), MTHFD1L (FC=0.7, p<0.01) and RMND1 (FC=1.4, p=0.013). Among Luminal-B (N=68) tumors, there was an association with ARMT1 (FC= 1.9, p=0.001), ESR1 (FC=1.4, p=0.04) and MTHFD1L (FC= 0.8, p=0.02). Only ESR1 was associated with the SNP (FC= 0.5, p= 0.03) among basal tumors (N=56). No association was identified among Luminal-A tumors (N=55). rs141057867 showed evidence of cis-association with CLDN20 (FC=1.4, p=0.014) among HER2+ subtypes and rs184135739 with ZC3H12D (FC=2.1, p=0.02) and SUMO4 (FC=1.8, p=0.023) among Lumina-A tumors.

Two of the three novel IA SNPs are protective against BC and show association with gene expression. The rs140068132-G variant regulates the expression of genes in the 6q25 region in a subtype-specific manner. A possible mechanism explaining the protective effect of the rs140068132 polymorphism might be linked to the lower expression of MTHFD1L among G-allele carriers in some subtypes. This gene is deregulated in cancer and its expression is negatively associated with cancer survival, including BC.

Citation Format: Valentina A. Zavala, Xiaosong Huang, Sandro Casavilca-Zambrano, Jeannie Navarro-Vásquez, Carlos A. Castañeda, Guillermo Valencia, Zaida Morante, Monica Calderon, Julio E. Abugattas, Henry Gómez, Hugo Fuentes, Ruddy Liendo-Picoaga, Jose M. Cotrina, Katia Roque, Jule Vásquez, Luis Mas, Marco Gálvez-Nino, Jovanny Zabaleta, Tatiana Vidaurre, Laura Fejerman. Regulation of genes located in 6q25 by an Indigenous American genetic variant in breast cancer patients from Peru. [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 5237.

Abstract 1977: Body mass index genetic risk score and obesity related cancer risk in Black and White adults

A total of 13 cancers are known to be strongly associated with obesity. The purpose of this study was to examine the association between a composite genotype risk score (GRS) for high body mass index (BMI) and the odds of obesity-related cancer. A nested case-control study was created within the Pennington Center Longitudinal Study, an ongoing prospective cohort study of the effects of obesity and lifestyle factors on the development of chronic diseases and premature mortality in Black and White Americans. A total of 459 participants developed an obesity-related cancer, and after stratification by sex and race, incidence density sampling was applied to select matched control participants (2:1) of the same age as cases (± 2 y). After deletion of participants with missing data, the analytic sample included 1242 participants (435 cases;136 Black, 299 White). A BMI GRS was derived using 21 single nucleotide polymorphisms (SNPs) with consistent evidence of association from the literature and which showed concordant associations in effect size and direction in our cohort. The GRS score was computed by summing the number of BMI risk alleles. In a model including age, race, sex, exam year and smoking as covariates, the BMI GRS was significantly associated with obesity-related cancer [odds ratio (OR): 1.18; 95% confidence interval: 1.04, 1.34; p=0.01]. Further adjustment for BMI did not change the association [1.20; 1,06-1.36; p=0.004]. In conclusion, the BMI GRS appears to provide added value in identifying obesity-related cancer risk, even after adjustment for BMI. Future studies are required to validate these results and better delineate the phenotypic and genetic contributions of BMI to obesity-related cancer risk.

Citation Format: Peter T. Katzmarzyk, Shengping Yang, Justin C. Brown, Emily F. Mire, Jovanny Zabaleta. Body mass index genetic risk score and obesity related cancer risk in Black and White adults [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 1977.

Abstract P6-01-40: Integrative transcriptomic analysis and cohort validation identify key genes in chemotherapy treatment response in Latino breast cancer patients

Purpose: Breast cancer (BC) is one of the most frequent invasive cancers and one of the main causes of cancer mortality in women. Effective treatment interventions for BC are urgently required to improve survival rate and quality of life. Chemotherapy has been widely applied in BC treatment; however, therapeutic resistance remains an unresolved issue. Currently, only a minority of patients benefit from chemotherapy, emphasizing the need to identify more effective hub genes associated with therapy response. The overarching goal of this study is to assess hub genes correlated with BC chemotherapy treatment response via multiple databases and validate the workflow in an independent cohort of Hispanic/Latino (Colombian) women diagnosed with invasive Luminal B BC candidates for neoadjuvant chemotherapy. Design: Screening and multistep filtering of common genes correlated with chemotherapeutic response was performed by integrating differentially expressed genes between responders and non-responders in publicly available datasets. For each database, the differentially expressed genes (DEGs) between non-responders and responders were identified using GEO2R and LIMMA. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted for the identified common genes using Metascape and DAVID. Functional enrichment analysis and protein-protein interaction (PPI) network for DEGs were constructed using (STRING) database. Hub genes were identified from PPI network by Cytoscape software analysis. The mRNA expression of hub genes in BC and normal tissues was subsequently explored by UALCAN. Evaluation of the effect of hub genes on survival was performed using Kaplan-Meier plotter. Hub genes were imported into the DGIdb to obtain the potential for BC chemotherapy-associated treatment drugs. The previous workflow was then applied/validated to an Illumina high-throughput RNA sequencing of 50 Luminal B cases (HER2+ and HER2-) of Hispanic/Latino patients. Results: 490 DEGs were obtained from the intersection of five public databases. Pathway enrichment analysis revealed DEGs were associated with cell cycle, estrogen response, adaptive immune response, and regulation of kinase activity, among others. Thirty-two hub genes were identified from PPI network analysis with high degree nodes and betweennesscentrality. Significant differential expression of hub genes between BC tissue and normal tissues was observed in UALCAN. These genes were significantly associated with survival probability. Fifteen potential targeted therapeutic drugs were identified through DGIdb database. Validation workflow in independent Luminal B cohort showed 238 DEGs, 90 hub genes with high degree and enrichment in the regulation of hormone levels, cellular response to EGFR, signaling by ERBB2 and MAPK. GATA3 was the hub gene found in both databases and the validation set. Both databases and validation set show hub genes, enriched pathways, and drugs that indicate their close association with tumorigenesis and would contribute to acting an important role in therapy response prediction. Conclusions: This workflow was created using public databases and applied to a patient’s cohort of different ancestries. This methodology can successfully provide potential biomarkers that correlate with therapy response. Genes were selected from PPI network. Most of them were independent biomarkers of BC treatment response, including that in underrepresented patients. Moreover, these genes may exert critical function in non-response and progression.

Citation Format: Hedda Michelle Guevara-Nieto, Rafael Parra-Medina, Juan C. Mejia-Henao, Patricia López-Correa, Sandra Diaz, Jone Garai, Jovanny Zabaleta, Liliana López-Kleine, Alba L. Combita. Integrative transcriptomic analysis and cohort validation identify key genes in chemotherapy treatment response in Latino breast cancer patients [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-01-40.

Evaluation of genetic alterations in hereditary cancer susceptibility genes in the Ashkenazi Jewish women community of Mexico

Background: Individuals of Ashkenazi Jewish ancestry have been identified as having higher prevalence of specific pathogenic variants associated with susceptibility to specific rare and chronic diseases. In Mexico, the prevalence and composition of rare cancer predisposing germline variants in Ashkenazi Jewish individuals has not been evaluated. Aim and methods: We aimed to evaluate the prevalence of pathogenic variants by massive parallel sequencing in a panel of 143 cancer-predisposing genes in 341 women from the Ashkenazi Jewish community of Mexico, who were contacted and invited to participate in the study through the ALMA Foundation for Cancer Reconstruction. Pre- and posttest genetic counseling was given and a questionnaire on personal, gyneco-obstetric, demographic and lifestyle variables was conducted. From peripheral blood DNA, the complete coding region, and splicing sites of a panel of 143 cancer susceptibility genes, including 21 clinically relevant genes, were sequenced. The Mexican founder mutation BRCA1 ex9-12del [NC_000017.10(NM_007294):c. (825+1-826-1)_(4,589+1-4,590-1)del] was also evaluated. Results: Among study participants (mean age ±standard deviation: 47 ± 14) 15% reported a personal history of cancer (50/341). Fourteen percent of participants (48/341) were carriers of pathogenic and likely pathogenic variants distributed among seven high-risk genes (APC, CHEK2, MSH2, BMPR1A, MEN1, MLH1, and MSH6), whereas 18.2% (62/341) had variants of uncertain clinical significance in genes associated with breast and ovarian cancer susceptibility (list of genes with VUS). Pathogenic and likely pathogenic variants in 16 susceptibility genes with ambiguous or non-well-established risk association for cancer were detected in 17.6% (60/341) of participants. Sixty four percent of participants reported current alcohol consumption compared with the 39 percent prevalence of alcohol consumption in Mexican women. None of the participants carried the recurrent Ashkenazi and Mexican founder mutations in BRCA1 or BRCA2, but 2% (7/341) had pathogenic Ashkenazi Jewish founder variants in BLM. Conclusion: Our findings show a diverse pathogenic variant composition among the recruited individuals of Ashkenazi Jewish ancestry in Mexico consistent with being a high-risk population for genetic diseases, which warrants further investigation to adequately assess the burden of hereditary breast cancer in this group and implement appropriate preventative programs.

Metabolic pathways enriched according to ERG status are associated with biochemical recurrence in Hispanic/Latino patients with prostate cancer

BACKGROUND

The role of ERG-status molecular subtyping in prognosis of prostate cancer (PCa) is still under debate. In this study, we identified differentially expressed genes (DEGs) according to ERG-status to explore their enriched pathways and implications in prognosis in Hispanic/Latino PCa patients.

METHODS

RNA from 78 Hispanic PCa tissues from radical prostatectomies (RP) were used for RNA-sequencing. ERG_high /ERG_low tumor groups were determined based on the 1.5-fold change median expression in non-tumor samples. DEGs with a False Discovery Rate (FDR) < 0.01 and a fold change >2 were identified between ERG_high and ERG_low tumors and submitted to enrichment analysis in MetaCore. Survival and association analyses were performed to evaluate biochemical recurrence (BCR)-free survival.

RESULTS

The identification of 150 DEGs between ERG_high and ERG_low tumors revealed clustering of most of the non-BCR cases (60%) into de ERG_high group and most of the BCR cases (60.8%) in ERG_low group. Kaplan-Meier survival curves showed a worst BCR-free survival for ERG_low patients, and a significant reduced risk of BCR was observed for ERG_high cases (OR = 0.29 (95%CI, 0.10-0.8)). Enrichment pathway analysis identified metabolic-related pathways, such as the renin-angiotensin system and angiotensin maturation system, the linoleic acid metabolism, and polyamines metabolism in these ERG groups.

CONCLUSIONS

ERG_low tumor cases were associated with poor BCR-free survival in our Hispanic/Latino patients, with metabolism-related pathways altered in the BCR progression.

IMPACT

Our findings suggest the need to dissect the role of diet, metabolism, and lifestyle as risk factors for more aggressive PCa subtypes.

A Recurrent ADPRHL1 Germline Mutation Activates PARP1 and Confers Prostate Cancer Risk in African American Families

African American (AA) families have the highest risk of prostate cancer. However, the genetic factors contributing to prostate cancer susceptibility in AA families remain poorly understood. We performed whole-exome sequencing of one affected and one unaffected brother in an AA family with hereditary prostate cancer. The novel non-synonymous variants discovered only in the affected individuals were further analyzed in all affected and unaffected men in 20 AA-PC families. Here, we report one rare recurrent ADPRHL1 germline mutation (c.A233T; p.D78V) in four of the 20 families affected by prostate cancer. The mutation co-segregates with prostate cancer in two families and presents in two affected men in the other two families, but was absent in 170 unrelated healthy AA men. Functional characterization of the mutation in benign prostate cells showed aberrant promotion of cell proliferation, whereas expression of the wild-type ADPRHL1 in prostate cancer cells suppressed cell proliferation and oncogenesis. Mechanistically, the ADPRHL1 mutant activates PARP1, leading to an increased H2O2 or cisplatin-induced DNA damage response for prostate cancer cell survival. Indeed, the PARP1 inhibitor, olaparib, suppresses prostate cancer cell survival induced by mutant ADPRHL1. Given that the expression levels of ADPRHL1 are significantly high in normal prostate tissues and reduce stepwise as Gleason scores increase in tumors, our findings provide genetic, biochemical, and clinicopathological evidence that ADPRHL1 is a tumor suppressor in prostate tissue. A loss of function mutation in ADPRHL1 induces prostate tumorigenesis and confers prostate cancer susceptibility in high-risk AA families.

IMPLICATIONS

This study highlights a potential strategy for ADPRHL1 mutation detection in prostate cancer-risk assessment and a potential therapeutic application for individuals with prostate cancer in AA families.

IL-1β enhances cell viability and decreases 5-FU sensitivity in novel colon cancer cell lines derived from African American patients

Background

In the U.S., African Americans (AAs) present with the highest incidence and mortality rates for Colorectal Cancer (CRC). When compared to Caucasian American (CA) patients, AAs also have reduced response to the first line standard of care chemotherapeutic agent 5-Fluorouracil (5-FU). Previously, we observed differential gene expression between the two populations, suggesting that colon tumors from AA patients display a decreased antitumor immune response and an increased expression of genes encoding proteins involved in inflammatory processes, such as Interleukin-1β (IL-1β). Here, we investigate the role of IL-1β in modifying chemotherapeutic response and altering expression of proteins in novel AA and well-established CA colon cancer cell lines.

Methods

RNA sequencing analysis was performed to detect expression of genes involved in inflammation in AA and CA colon cancer cells. The effects of IL-1β on 5-FU response was evaluated by assessing cell viability (MTS assay) and apoptosis (flow cytometry analysis) following treatment with 5-FU alone or in combination with the cytokine. Further, we used an IL-1 receptor antagonist (IL-1Ra) to inhibit IL-1β-induced effects on 5-FU sensitivity and NF-kB pathway activation.

Results

AA colon cancer cell lines present significant increase in expression of genes IL1R2 (373-fold change (FC), IRAK1 (3.24 FC), IKBKB, (5.33 FC) NF-KB IA (5.95 FC), MYD88, (3.72 FC), IRAK3 (161 FC), TRAF5 (4.1 FC). A significant decrease in the response to 5-FU treatment, as well as a significant increase in phosphorylation of IκBα and secretion of IL-8, was seen following IL-1β treatment, in both AA and CA cell lines. Finally, treatment with IL-1Ra was able to reverse the effects induced by IL-1β, by increasing the cells sensitivity to 5-FU. IL-1Ra also inhibited phosphorylation of IκBα and IL-8 secretion.

Conclusions

Our results suggest a differential expression of inflammatory genes and proteins that might regulate the different response to IL-1β between AA and CA colon cancer cell lines. Our data also demonstrates that IL-1β is involved in modulating 5-FU response in both AA and CA colon cancer cell lines. Further investigation of these mechanisms might help elucidate the differences seen in incidence, mortality and response to therapy in AA colon cancer patients.

New Insights into Avian Infectious Bronchitis Virus in Colombia from Whole-Genome Analysis

Infectious Bronchitis (IB) is a respiratory disease caused by a highly variable Gammacoronavirus, which generates a negative impact on poultry health worldwide. GI-11 and GI-16 lineages have been identified in South America based on Infectious Bronchitis virus (IBV) partial S1 sequences. However, full genome sequence information is limited. In this study we report, for the first time, the whole-genome sequence of IBV from Colombia. Seven IBV isolates obtained during 2012 and 2013 from farms with respiratory disease compatible with IB were selected and the complete genome sequence was obtained by NGS. According to S1 sequence phylogenetic analysis, six isolates belong to lineage GI-1 and one to lineage GVI-1. When whole genome was analyzed, five isolates were related to the vaccine strain Ma5 2016 and two showed mosaic genomes. Results from complete S1 sequence analysis provides further support for the hypothesis that GVI-1, considered a geographically confined lineage in Asia, could have originated in Colombia. Complete genome information reported in this research allow a deeper understanding of the phylogenetic evolution of variants and the recombination events between strains that are circulating worldwide, contributing to the knowledge of coronavirus in Latin America and the world.

Association between Ancestry-Specific 6q25 Variants and Breast Cancer Subtypes in Peruvian Women

BACKGROUND

Breast cancer incidence in the United States is lower in Hispanic/Latina (H/L) compared with African American/Black or Non-Hispanic White women. An Indigenous American breast cancer-protective germline variant (rs140068132) has been reported near the estrogen receptor 1 gene. This study tests the association of rs140068132 and other polymorphisms in the 6q25 region with subtype-specific breast cancer risk in H/Ls of high Indigenous American ancestry.

METHODS

Genotypes were obtained for 5,094 Peruvian women with (1,755) and without (3,337) breast cancer. Associations between genotype and overall and subtype-specific risk for the protective variant were tested using logistic regression models and conditional analyses, including other risk-associated polymorphisms in the region.

RESULTS

We replicated the reported association between rs140068132 and breast cancer risk overall [odds ratio (OR), 0.53; 95% confidence interval (CI), 0.47-0.59], as well as the lower odds of developing hormone receptor negative (HR-) versus HR+ disease (OR, 0.77; 95% CI, 0.61-0.97). Models, including HER2, showed further heterogeneity with reduced odds for HR+HER2+ (OR, 0.68; 95% CI, 0.51-0.92), HR-HER2+ (OR, 0.63; 95% CI, 0.44-0.90) and HR-HER2- (OR, 0.77; 95% CI, 0.56-1.05) compared with HR+HER2-. Inclusion of other risk-associated variants did not change these observations.

CONCLUSIONS

The rs140068132 polymorphism is associated with decreased risk of breast cancer in Peruvians and is more protective against HR- and HER2+ diseases independently of other breast cancer-associated variants in the 6q25 region.

IMPACT

These results could inform functional analyses to understand the mechanism by which rs140068132-G reduces risk of breast cancer development in a subtype-specific manner. They also illustrate the importance of including diverse individuals in genetic studies.

Association of Abdominal Visceral Adiposity and Total Fat Mass with Cancer Incidence and Mortality in White and Black Adults

BACKGROUND

Race modifies the association between anthropometric measures of obesity and cancer risk. However, the degree to which abdominal visceral adipose tissue (VAT) and total fat mass (FM) are associated with cancer risk is not known.

METHODS

The sample included 3,017 White and 1,347 Black adults who were assessed between 1995 and 2016 and followed for outcome assessment through 2017. Abdominal VAT and FM were measured using imaging techniques. The co-primary endpoints were diagnosis of histologically confirmed invasive cancer (excluding nonmelanoma skin cancer) or death from cancer. Multivariable Cox proportional hazards models quantified the HR of incident cancer and cancer mortality.

RESULTS

There were 353 incident cancer cases and 75 cancer deaths in an average of 12.9 years of follow-up. Both VAT [HR, 1.21; 95% confidence interval (CI), 1.09-1.36] and FM (HR, 1.25; 95% CI, 1.10-1.43) were significantly associated with incident cancer, while VAT (HR, 1.28; 95% CI, 1.01-1.61) was significantly associated with cancer mortality after adjustment for several covariates. VAT remained significantly associated with cancer incidence (HR, 1.22; 95% CI, 1.03-1.46) after additional inclusion of FM in the multivariable model, but not vice versa. There were no significant sex- or race-interactions.

CONCLUSIONS

VAT was associated with risk of cancer and cancer mortality in this cohort, and the associations did not differ by sex or race. The association between VAT and incident cancer was largely independent of total FM.

IMPACT

Our results suggest that utility of anthropometry in assessing obesity-related cancer risk may need to be further refined by including more direct measures of adiposity.

The COVID-19 pandemic and associated increases in experiences of assault violence among black men with low socioeconomic status living in Louisiana

Background

The COVID-19 pandemic has had mental health, social, and economic implications among communities with high levels of social disadvantage; this may have impacted community violence rates. The objective of this study was to characterize overall trends in assault and social disadvantage of patients experiencing assault before and during the COVID-19 pandemic.

Methods

All trauma activations at a level one trauma center serving the entire southeast Louisiana region were included during March–August pre-COVID (2018–2019) and during COVID (2020). ICD-10 E-codes were used to identify trauma intent (assault vs. other). Assaults in this context are defined as physical injuries caused by an act of violence wherein the perpetrator was suspected or confirmed to have intended harm, injury, or death to the victim. Social disadvantage was assessed using the Area Deprivation Index (ADI). Change in the monthly rate of assault-trauma activations was assessed using negative binomial regression with adjustment for race, gender, and injury intent. The study was reviewed and approved by the Louisiana State University Health Sciences Institutional Review Board.

Results

A total of 4,233 trauma activations were included. The majority of activations occurred among men. Assaults increased from 27.5% of all activations pre-Covid to 35.6% during the pandemic. Penetrating trauma similarly increased from 29.5% to 35.7% of all activations. Negative binomial regression demonstrated that in addition to this increase in proportion of assaults relative to all activations, the monthly assault rate also increased by 20% during the pandemic. These increases were driven primarily by increased assaults among Black men. ADI rank did not change between study periods.

Conclusions

Health disparities in violence worsened during the pandemic: increased cases of assault occurred disproportionately among Black men, and assaults persisted in occurring primarily among low-ADI communities where burden had been high pre-pandemic. There is a critical need for resources and support to Black men, to mitigate violence and improve racial heath equity.

PTSD treatment reduces risk of trauma recidivism in a diverse community at a safety-net hospital: A propensity score analysis of data from a level one trauma center

BACKGROUND

Physically-traumatic injuries result in PTSD for approximately 10% of Americans, and this rate is higher among individuals of color and those living in poverty. Individuals of color living in poverty experience lower access to PTSD and other mental health services. Untreated PTSD is associated with increased risk of trauma recidivism, but it is unknown if provision of treatment is actually associated with a subsequent reduction in recidivism risk.

METHODS

For this observational cross-sectional study, data were collected retrospectively from the Trauma Registry of a level one trauma center, safety-net hospital in New Orleans between 2018 and 2020. Receipt of outpatient PTSD treatment at this same hospital was evaluated via chart review of the electronic health record. Propensity score matching was used to balance confounding variables of trauma type (assault vs. non-assault), gender, and race. McNemar test and Cox proportional hazard model were used with the propensity-balanced dataset to assess differences in trauma recidivism according to PTSD treatment status.

RESULTS

Among 5916 trauma activations that occurred in the study period, 92 instances of recidivism occurred. 91 pairs were established after balancing with the propensity score. 1-year recidivism was 2.2% (n = 2) of all treated individuals versus 15.4% (n = 14) of non-treated individuals (p < 0.0001). The marginal risk from the Cox proportional hazard model demonstrated an 82% reduction in risk of recidivism (p = 0.02).

CONCLUSIONS

This study demonstrated that mental health treatment can be used to reduce trauma recidivism. These data were shown among a high-risk population of disproportionately Black men living in a low-income community. Ensuring access to quality mental health care is one way to address the health disparities associated with physically-traumatic injuries.

Abstract 1497: miRNA expression analysis in high-risk HPV-positive cervical scrapes for the detection of cervical disease

Cervical cancer is the fourth most frequently diagnosed cancer and the fourth leading cause of cancer death in women, with an estimated 604,000 new cases and 342,000 deaths worldwide in 2020. Persistent infections with high-risk HPV (hrHPV) genotypes can lead to high-grade lesions (Cervical Intraepithelial Neoplasia Grade 2 or higher, CIN2+), that if left untreated progress to cancer. hrHPV test has high sensitivity to detect CIN2+, but it has low specificity because close to 90% of women spontaneously clear the infection. Biomarkers to stratify hrHPV+ women with cervical lesions that may progress to cancer are needed. miRNAs are small noncoding RNAs that regulate gene expression, can be detected in cervical scrapes, and are differentially expressed between high- and low-grade lesions.

Aim To identify miRNAs differentially expressed between CIN3+ and ≤CIN1 lesions and evaluate their potential use as biomarkers to distinguish CIN3+ in hrHPV+ women.

Methods We used miRNAseq to compare miRNAs expression patterns in cervical scrapes of hrHPV+ women: 35 with low-grade lesions (NEG= 26; CIN1= 9) and 36 with high-grade lesions (CIN3= 32; SCC= 4). The samples were collected through the ASCUS-COL Trial in Medellin, Colombia. Women with low- or high-grade cervical lesions exhibit similar sociodemographic characteristics (Chi-square p-values&gt;0.05). The RNAseq data were processed in GeneGlobe-QIAGEN, which incorporates cut-adapt, bowtie and DeSEq2. Receiver Operating Characteristic (ROC) analyses with a 95% confidence interval of Area Under the Curve (AUC) were made to evaluate the diagnostic accuracy of each miRNA differentially expressed, to detect CIN3+. Multivariate Logistic Regression Analysis using normalized counts of mapped reads identified a combination of the differentially expressed miRNAs that best predicted CIN3+. We identified putative pathways using MetaCore.

Results An average of &gt;9 million reads by sample and around 3.5 million reads mapped to miRBase V21 was obtained. The principal component analysis did not show factors that could introduce bias to differential gene expression analysis. We identified 38 miRNAs differentially expressed. Compared to &lt;CIN1 lesions, 9 miRNAs were overexpressed and 29 underexpressed in CIN3+ lesions. Six miRNAs presented AUC&gt;0.60 (p-value &lt;0.05) to detect CIN3+. The best predictive combination of 9 miRNAs exhibits an AUC of 0.89, 95% CI (0.83 - 0.97), of which 4 were overexpressed and 5 underexpressed in CIN3+ vs &lt;CIN1. Interestingly, 5 miRNAs underexpressed in CIN3+, target VEGF, a known angiogenic mediator linked to malignancy.

Conclusion We identified miRNAs differentially expressed with good diagnostic performance to distinguish high- from low-grade lesions in cervical scrapes samples. Further validation on a larger cohort of cervical scrapes samples is needed to confirm the potential role of these miRNAs to triage hrHPV+ women.

Citation Format: Martha Isabel González Ramírez, Samuel Agudelo, Maria Cecilia Agudelo, Jone Garai, Li Li, Carlos Alberto Orozco Castaño, Jovanny Zabaleta, Gloria Inés Sánchez Vásquez. miRNA expression analysis in high-risk HPV-positive cervical scrapes for the detection of cervical disease [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1497.

Abstract 2525: Understanding triple-negative breast cancer immune microenvironment by disease stages, obesity, and race

Background: Triple-negative breast cancer (TNBC) is a molecularly heterogeneous group of clinically aggressive malignancies. There are well-recognized health disparities in TNBC outcomes, and the risk of TNBC is higher among African-Americans (AA). It is unclear whether immunological features of the tumor microenvironment (TME) associated with disease stage, socioeconomic factors, or comorbidities such as obesity may affect tumor immunity. The incidence of TNBC and obesity in Louisiana is among the highest in the nation, and we have documented disparities in incidence linked to race and disparities in mortality linked to social determinants of health. Recent studies described immunologic characteristics of the TNBC TME. However, the possible association of immunogenomic portraits of TNBCs with race, comorbidities or socioeconomic factors remains understudied.

Methods: We studied the expression of immunity-associated genes in clinically annotated TNBCs from Louisiana AA and European-American (EA) patients with or without obesity. Primary invasive breast cancer cases with confirmed TNBC diagnosis were identified by the Louisiana Tumor Registry (LTR). Sections of FFPE tissue containing ≥ 50% tumor were identified and processed for RNA-Sequencing [(n = 256; White women:125 (Lean: 50 and Obese:75) and Black women:131 (Lean:28 and Obese: 103)] at Translational Genomic Core, LSUHSC. Categorical outcomes were compared via Chi-squared tests, and survival was compared via log-rank tests. Spearman correlation analysis was used to determine associations between CIBERSORT cell populations and stage of disease at diagnosis.

Results: We found that race was associated with the stage of TNBC, and AA patients were more often diagnosed with a later stage of TNBC (p=0.0447). However, race was not associated with survival (p=0.4673). Obesity was not associated with stage at diagnosis (p=0.7256). Stage at diagnosis was the strongest determinant of survival (p&lt;0.0001). We utilized CIBERSORT analysis to identify and quantify immune cell populations within the TME. Later stage at diagnosis was associated with increased T follicular helper cells (p=0.0038), M1 macrophages (p= 0.0032), and activated mast cells (p=0.0487). Conversely, later stage of disease was associated with decreased resting mast cells (p=0.0004) and monocytes (p=0.0455). Immunosuppressive Treg cells were positively associated with stage at diagnosis in AA patients (p=0.0273) but not in EA patients (p=0.9141).

Conclusions: Stage at diagnosis was the strongest determinant of survival and was associated with significant differences in TME immune cell populations. Stage, race and obesity were associated with the presence of immunosuppressive Treg cells. If confirmed, these findings may help understand the variability in immunotherapy responses in TNBC.

Citation Format: Fokhrul Hossain, Denise Danos, Jovanny Zabaleta, Jiande Wu, Mary Anne Lynch, Luis Del Valle, Xiao-Cheng Wu, Augusto Ochoa, Chindo Hicks, Lucio Miele. Understanding triple-negative breast cancer immune microenvironment by disease stages, obesity, and race [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2525.

Abstract 1477: Circulating miR-125a-3p and miR-451a may be liquid biopsy biomarkers for the diagnosis of breast cancer

Background: Breast cancer is the most prevalent female cancer. Emerging evidence suggests that the unique serum miRNAs can assist in the early detection and diagnosis of breast cancer. Cell-free circulating miRNAs (about 22 nucleotides) are potential diagnostic tools and minimally invasive biomarkers for breast cancer detection. This study aimed to identify specific microRNAs in the serum of patients with breast cancer, which may serve as promising diagnostic and prognostic biomarkers and therapeutic targets.

Material and methods: Next-generation sequencing and quantitative real-time PCR (qRT-PCR) array analyses of microRNAs in sera from different subtypes of breast cancer patients and normal female individuals were performed. The differentially expressed microRNAs were verified in serum samples from 100 breast cancer patients. The predictive values of the selected microRNAs were statistically analyzed, determined by the correlation between microRNA expression and tumor parameters. Datasets were graphed using GraphPad Prism Software 8.0. and analysis was done using one-way ANOVA with unpaired two-tailed Student’s t-test.

Result: High serum levels of miR-125a-3p and miR-451a were found to be associated with breast cancer tumor subtype, size, and lymph node metastasis. Further functional in vitro experiments and enrichment analysis showed that overexpression and knockdown of miR-451 might significantly affect tumorigenic signaling pathways in TNBC cells.

Conclusion: Altogether, our data suggested that serum levels of microRNAs miR-125a-3p and miR-451a can potentially serve as liquid biopsy biomarkers in breast cancer.

Citation Format: Hassan Yousefi, Steven C. Eastlack, Jordyn T Fong, Samuel C. Okpechi, Jovanny Zabaleta, Lyndsey R. Buckner, Donnalee N Trapani, Erin Sims, Alison McDaniel McDaniel, Heather Scuderi, Meredith A. Lakey, John T. Cole, Suresh K. Alahari. Circulating miR-125a-3p and miR-451a may be liquid biopsy biomarkers for the diagnosis of breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1477.

Abstract 100: IL-1β pathway promotes cell proliferation and 5-FU resistance in African American colon cancer cell lines

Introduction: Colorectal Cancer (CRC) is the third most common cancer and third cause of cancer-related death in the US. When taking race and ethnicity into consideration, African Americans (AA) present with the highest incidence and mortality rates for CRC. Studies have found that AA patients, when compared to Caucasian American (CA) patients, have a lower response to the standard of care chemotherapeutic agent 5-Fluorouracil (5-FU) as well as lower frequency of MSI tumors, making them also less likely to respond to conventional immunotherapies. Our recent findings have shown that tumors from AA patients present higher expression of genes involved in pro-inflammatory processes as well as lower expression of genes promoting anti-tumoral activities. One of the genes that was found upregulated in AA tumors is IL1B, which encodes for the pro-inflammatory cytokine Interleukin-1β (IL-1β). Therefore, we investigated the role of the IL-1β pathway in novel AA colon cancer cell lines. Here, we evaluated changes in cell proliferation, apoptosis, 5-FU response, and activation of inflammatory pathways.

Methods: Our approach includes analysis of gene expression in both AA and CA colon cancer cell lines by using RNA sequencing to evaluate pro-inflammatory genes differentially expressed among the cell lines. Furthermore, we used an MTS assay to detect viable cells following treatment with IL-1β, alone or in combination with different concentrations of 5-FU, as well as analyzing changes in apoptosis via Flow Cytometry. To better understand the mechanisms of IL-1β-induced effects, we used IL-1 Receptor Antagonist (IL-1Ra) to block the IL-1β pathway and evaluated changes in cell viability and 5-FU response via MTS assay, as well as activation of NF-kB pathway, via detection of phospho-IкB-α protein using Western Blot analysis.

Results: Results from MTS assays indicated that cell proliferation in response to IL-1β differs between the AA and the CA colon cancer cell lines, with the AA colon cancer cells being more sensitive to lower concentrations of the cytokine when compared to CA cell lines. Further, we saw an increased expression of phospho-IкB-α following treatment with IL-1β. This expression was reduced when the cells were treated in combination with IL-1β and the IL-1Ra. The IL-1Ra also appears to reduce the pro-proliferative effects induced by IL-1β. Importantly, our results show that 5-FU sensitivity is drastically reduced in the presence of IL-1β for both AA and CA colon cancer cell lines, suggesting that IL-1β may play a role in defining resistance to the chemotherapeutic drug.

Conclusions: Taken together, our results demonstrated a differential response to IL-1β for the AA colon cancer cell lines, suggesting a probable role played by the cytokine in driving inflammation-related cancer progression and reveals a possible new target to exploit in immunotherapy for this population.

Citation Format: Marzia Spagnardi, Jenny Paredes, Jone Garai, Jovanny Zabaleta, Jennie Williams, Laura Martello-Rooney. IL-1β pathway promotes cell proliferation and 5-FU resistance in African American colon cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 100.

Abstract 3658: Ototoxicity of chemotherapy and radiation agents used in pediatric cancer treatment

Many highly effective therapies used to treat cancer have been associated with irreversible development of detrimental neurological sequelae following the survival of childhood and adolescent cancer. While cancer treatment-induced late effects vary due to patient-related risk factors, cancer survivors who received chemotherapy or radiation may develop conductive or sensorineural hearing loss (SNHL). The purpose of this project is to determine which neuroinflammation-associated genes and biological pathways are affected by pediatric cancer treatments, and which treatment protocols are associated with increased ototoxicity. We hypothesize that cancer treatment causes abnormal gene expression of neuroinflammation and deafness-associated genes. The hypothesis will be tested with two specific aims. Aim I is to perform a retrospective review of diagnostic audiograms from pediatric cancer survivors enrolled in the Treatment After Cancer and Late Effects Center at Children’s Hospital New Orleans, Louisiana (CHNOLA). Aim II is to perform Nanostring neuroinflammation gene expression analysis followed by Ingenuity Pathway Analysis (IPA) of brain autopsy specimens from deceased pediatric patients who have previously undergone cancer treatment (Pathology Department, CHNOLA). Preliminary results revealed abnormal upregulation or downregulation of key genes, some of which are related to hearing loss and cochlear neuron degeneration when compared to age-matched controls (e.g., GJA1 and CASP3). The present study may provide information regarding which cancer treatment agents are ototoxic and reveal the candidate risk genes and pathways that contribute to auditory late effects. The long term goal of this project is to identify the needs of cancer survivors who are affected by treatment-induced hearing loss and provide them and their families with access to educational materials, medical resources, and social support to increase their health-related quality of life.

Citation Format: Brittney T. Moore, Fern Tsien, Gabrielle Sheets, Ayesha Umrigar, Jordan Doss, Michael Norman, Matthew Stark, Pinki Prasad, Amanda Musso, Chindo Hicks, David Otohinoyi, Jovanny Zabaleta, Li Li. Ototoxicity of chemotherapy and radiation agents used in pediatric cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3658.

Abstract 5143: Gene expression profiles associated with induction treatment response in pediatric patients with acute lymphoblastic leukemia type B

Acute lymphoblastic leukemias (ALL) are the most common hematopoietic neoplasms in children. Survival in developed countries is &gt;80%, while in Colombia is ≤60%. These differences have been related to different factors, including genetic and epigenetic alterations, which could regulate chemoresistance mechanisms. Currently, some genetic alterations have been used to classify patients in a risk group, but a genetic profile that can be applicable to most patients to predict with high sensitivity the response to induction chemotherapy, improve the risk classification and predict survival is highly needed. We aim to identify gene profiles associated with response to induction chemotherapy in pediatric patients with ALL-B.

Methods: Bone marrow samples were collected from 27 patients with a new diagnosis of B-ALL. Blasts were separated and purified according to the expression of the CD19 and CD34. RNA was extracted and used as template for genomic libraries. RNA-seq was done using the Illumina platform, and the reads were aligned and quantified using Partek Flow. DEseq2 was used for statistical analysis and to determine the differentially expressed genes (DEG) between the patient groups. Response to induction treatment was defined (flow cytometry) as positive or negative minimal residual disease (MRD) as percentage of residual blasts &gt;0.01% or &lt;0.01%, respectively. Three comparison groups were defined: 1) true responders (MRD- at day 15 and MRD- at the end of induction) vs. true non-responders (MRD+ at day 15, and MRD + at the end of induction), 2) MRD- vs MRD+ at the 15 day of induction; 3) MRD- vs MRD+ at the end of induction. Genes with a p &lt;0.05 and a fold change &gt;2 were chosen. Additionally, an enrichment analysis was performed to determine the signaling pathways associated with treatment response.

Results: 159 DEGs were found among MRD- vs MRD+ at day 15 of the induction, 200 DEGs were identified between MRD- vs. MRD+ at the end of induction, and 153 DEGs were found between patients classified as true responders vs. true non-responders. Additionally, to determine the genes that could be predicting the response to treatment, a comparison was made between the DEGs of each group of patients analyzed, finding 50 genes in common. Interestingly, the genes identified are associated with differentiation of stem cells (HOXB2), metabolic process (ST8SIA6, SPHK1, HPGD), immune response (CFH, PAR2, NFAM), cell-cell signaling (PEAR1, PTGIR), and ion transmembrane transport (SLC2A7, SLC45A3). The overexpression of these genes is associated with a poor response to induction chemotherapy.

Conclusion: We identified 50 genes associated with the response to induction chemotherapy in pediatric patients with ALL-B. Those genes are associated with signaling pathways that could be explaining the lack of response in patients and might serve as possible biomarkers of response to induction treatment.

Citation Format: Yulieth X. Torres-Llanos, Jovanny Zabaleta, Nataly Cruz-Rodriguez, Sandra M. Quijano, Paula C. Guzmán, Iliana De Los Reyes, Ana M. Infante, Liliana Lopez, Alba L. Combita. Gene expression profiles associated with induction treatment response in pediatric patients with acute lymphoblastic leukemia type B [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5143.

Abstract 2355: Intratumoral translocation positive heterogeneity in pediatric alveolar rhabdomyosarcoma tumors correlates to changes in genes predicted to inhibit the immunological response

Alveolar rhabdomyosarcoma (ARMS) is characterized by one of three translocation states: t(2;13)(q35;q14) producing PAX3-FOXO1, t(1;13)(p36;q14) producing PAX7-FOXO1, or translocation-negative. Tumors with t(2;13) are associated with greater disease severity and mortality than t(1;13) positive or translocation negative patients. We demonstrated that ARMS tumor samples contain intratumoral genetic heterogeneity with respect to the presence of t(2;13). Further, we demonstrated that this heterogeneity had an inverse correlation with tumor aggressiveness, with tumors containing higher translocation positivity having lower failure-free survival of patients. However, it is not yet known whether a correlation exists between percent t(2;13) positivity and changes in gene expression, in particular genes whose function contributes to immune invasion in the tumor microenvironment. Of fifty-five rhabdomyosarcoma patient tumor samples received from Children’s Hospital in New Orleans, nine were confirmed to contain t(2;13) ranging from 16 - 98% cells positive for the translocation. We used aged-matched normal muscle tissue derived from autopsies as a control. RNA was isolated from whole tissue samples and analyzed using the Nanostring nCounter®️ PanCancer IO 360™ Panel. This panel contains 770 genes that specifically analyze tumor immunogenicity, tumor sensitivity to immune attack, inhibitory immune mechanisms, stromal factors, inhibitory metabolism, anti-tumor immune activity, inhibitory immune signaling, immune cell population and abundance, and tumor inflammation. We found 487 genes have an average change in expression ≥ 1.5-fold relative to the control. Of these genes 31 (6.4%) have a statistically significant positive correlation and nearly 25% (114 genes) had a statistically significant negative correlation to percent intratumoral translocation positivity. A closer examination indicated that genes with a negative correlation had biological functions that target a variety of different immunological processes. These include the recognition of antigen by T cells; the activation, maturation, and differentiation of lymphocytes and myeloid cells; adhesion of immune responsive cells; promotion of the inflammatory response; and activation of the innate immune response. These results suggest that increased intratumoral t(2;13) positivity negatively impacts the immunological response thereby increasing the ability for immune evasion of the tumors with higher levels of the translocation, a result consistent with our previously published work.

Citation Format: Andrew D. Hollenbach, Matthew Stark, Jovanny Zabaleta, Fern Tsien. Intratumoral translocation positive heterogeneity in pediatric alveolar rhabdomyosarcoma tumors correlates to changes in genes predicted to inhibit the immunological response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2355.

Abstract 2121: Gene expression and functional characterization of obesity-induced MDSC to uncover the link between obesity and cancer risk

Strong epidemiologic evidence suggests that excess body weight gain is a major risk of at least 13 different types of cancers. One of the mechanisms explaining the increased cancer incidence in obese patients is associated with the chronic low-grade inflammatory condition. Myeloid cells including macrophages and Myeloid-derived suppressor cells (MDSC) are increased in advanced adiposity. Previous studies in mouse models have shown that obesity-induced MDSC play a protective role on metabolic control; however, in the presence of malignant cells, MDSC facilitates tumor growth and metastasis. Our data show that compared to non-obese individuals, patients with severe obesity (body mass index [BMI] &gt; 40) have a significant increase of circulating granulocytic cells displaying a gene signature resembling tumor-MDSC. Intriguingly, obesity-induced MDSC lacked the potent immunosuppressive function; and therefore, we called them obesity-induced G-MDSC-like cells (Ob-MDSC). The mechanisms underlying the regulation of MDSC phenotype in obesity and obesity-related cancer are unclear. We found that LDL, one altered obesity-related factor, and LPS differentially impact the expression of several genes including the immunosuppressive MDSC markers, arginase-1 and iNOS, when comparing mouse bone marrow-derived MDSC from high-fat fed mice with low-fat fed mice. This finding indicates that the responsiveness of MDSC may be regulated by their long-lasting exposure to the obese microenvironment. Therefore, we propose that long-term adaptation of MDSC is induced by dysfunctional metabolic factors in obesity that modulate their response to subsequent triggers, such as signals derived by the tumor microenvironment (TMA) in the context of obesity-associated cancer. Our data from obese mice with Diethylnitrosamine (DEN)-induced hepatocellular carcinoma and genetically altered hepatic lipid and lipoprotein metabolism show an increased infiltration of G-MDSC associated with enhanced tissue chemokine signaling pathway, ECM remodeling/metastasis, inflammation, and epigenetic and transcriptional regulation. Together our data suggest that chronic exposure to an obesity-related environment establishes a phenotype prone to become pro-tumor MDSC. The identification of key regulators of the gene expression driving the immunosuppressive phenotype of MDSC in obesity is critical for the discovery of therapeutical targets to reduce the risk of obesity-associated cancers.

Citation Format: Maria D. Sanchez-Pino, Ramesh Thylur Puttalingaiah, Jone Garai, Jovanny Zabaleta, Randall L. Mynatt, William Richardson, Augusto Ochoa. Gene expression and functional characterization of obesity-induced MDSC to uncover the link between obesity and cancer risk [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2121.

Abstract 1255: Identification of predictive biomarkers for neoadjuvant chemotherapy response in invasive breast cancer Latino patients

Purpose: Breast cancer (BC) is the leading cause of morbidity and mortality in women in Colombia, constituting a major public health issue. Importantly, not all breast cancer patients respond to neoadjuvant chemotherapy (NAC), leading to an incomplete pathological response and suggesting that there are tumor characteristics that may explain the differences in response. The overarching goal of this study is to identify gene expression profiles associated with an incomplete pathological response to NAC in Colombian women with invasive BC.

Design: An integrative transcriptome analysis using Illumina high-throughput RNA sequencing was performed from 63 baseline and post-NAC (follow-up) paraffin-embedded samples from 46 different female patients with locally advanced BC (stage IIB to IIIC) treated at the Colombian National Cancer Institute. Gene expression data were obtained from 42 baseline and 21 follow-up samples. Two comparison analyses were conducted to identify differentially expressed genes (DEGs) first comparing baseline vs follow-up samples from nonresponders to NAC and second comparing to baseline samples from nonresponders vs responders to NAC. Additionally, enrichment analyses were performed in both comparative analyses.

Results: From 46 patients included, 20 had a pathological complete response (pCR), while 26 did not show pCR. By investigating the gene expression profiling, 1546 significantly DEGs and 174 DEGs were identified among non-responders and Baseline analyses, respectively. From these analyses, 24 DEGs were found in common and apoptosis as the only shared enrichment pathway (p=0.001). In both analyses, Histone associated genes were downregulated in nonresponders (Histone 3, p=0,001 and Histone 2B, p&lt;0,001). In addition, downregulation of Granzyme B and perforin were also found differentially expressed in apoptosis network pathways. CD8+ naïve T-cells, hematopoietic stem cells, Macrophages, Macrophages M1, Neurons, Th1 cells, activated dendritic cells and pro B cells were defined by the xCell algorithm and showed statistically significant association with non-response to NAC.

Conclusions: Changes in histones and tumor microenvironment cell populations elicits local immune response, which contributed to therapeutic efficacy. Downregulation of Granzyme B and perforin could block mechanism of resistance to carcinogenesis, leading to non-response to NAC. Furthermore, patients with tumors containing higher gene signatures of these DEGs may benefit from NAC. Additional validations are needed to confirm these data. If confirmed, these data may be relevant in elucidating the mechanisms that lead to therapy resistance as well as in selecting patients that will benefit from NAC in Latino (Colombian) patients.

Citation Format: Hedda Michelle Guevara-Nieto, Rafael Parra-Medina, Juan Carlos Mejia-Henao, Patricia Eugenia López-Correa, José Ismael Guío-Avila, Sandra Diaz-Casas, Jone Garai, Jovanny Zabaleta, Liliana López-Kleine, Alba Lucia Cómbita. Identification of predictive biomarkers for neoadjuvant chemotherapy response in invasive breast cancer Latino patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1255.

Nox4 expression in osteo-progenitors controls bone development in mice during early life

Tightly regulated and cell-specific NADPH-oxidases (Nox) represent one of the major sources of reactive oxygen species (ROS) signaling molecules that are involved in tissue development and stem cell self-renewal. We have characterized the role of Nox4 in osteo-progenitors during postnatal bone development. Nox4 expression in bone and ROS generation were increased during early osteoblast differentiation and bone development. Stromal osteoblastic cell self-renewal, proliferation and ROS production were significantly lower in samples from whole-body Nox4 knockout mice (Nox4^-/-) and conditional knockout (CKO) mice with depletion of Nox4 in the limb bud mesenchyme compared with those from control mice (Nox4^fl/fl), but they were reversed after 9 passages. In both sexes, bone volume, trabecular number and bone mineral density were significantly lower in 3-week old CKO and Nox4^-/- mice compared with Nox4^fl/fl controls. This was reflected in serum levels of bone formation markers alkaline phosphatase (ALP) and procollagen 1 intact N-terminal propeptide (P1NP). However, under-developed bone formation in 3-week old CKO and Nox4^-/- mice quickly caught up to levels of control mice by 6-week of age, remained no different at 13-week of age, and was reversed in 32-week old male mice. Osteoclastogenesis showed no differences among groups, however, CTX1 reflecting osteoclast activity was significantly higher in 3-week old male CKO and Nox4^-/- mice compared with control mice, and significantly lower in 32-week old Nox4^-/- mice compared with control mice. These data suggest that Nox4 expression and ROS signaling in bone and osteoblastic cells coordinately play an important role in osteoblast differentiation, proliferation and maturation.

Increased inflammatory low-density neutrophils in severe obesity and effect of bariatric surgery: Results from case-control and prospective cohort studies

BACKGROUND

Low-density neutrophils (LDN) are increased in several inflammatory diseases and may also play a role in the low-grade chronic inflammation associated with obesity. Here we explored their role in obesity, determined their gene signatures, and assessed the effect of bariatric surgery.

METHODS

We compared the number, function, and gene expression profiles of circulating LDN in morbidly obese patients (MOP, n=27; body mass index (BMI) > 40 Kg/m²) and normal-weight controls (NWC, n=20; BMI < 25 Kg/m²) in a case-control study. Additionally, in a prospective longitudinal study, we measured changes in the frequency of LDN after bariatric surgery (n=36) and tested for associations with metabolic and inflammatory parameters.

FINDINGS

LDN and inflammatory markers were significantly increased in MOP compared to NWC. Transcriptome analysis showed increased neutrophil-related gene expression signatures associated with inflammation, neutrophil activation, and immunosuppressive function. However, LDN did not suppress T cells proliferation and produced low levels of reactive oxygen species (ROS). Circulating LDN in MOP significantly decreased after bariatric surgery in parallel with BMI, metabolic syndrome, and inflammatory markers.

INTERPRETATION

Obesity increases LDN displaying an inflammatory gene signature. Our results suggest that LDN may represent a neutrophil subset associated with chronic inflammation, a feature of obesity that has been previously associated with the appearance and progression of co-morbidities. Furthermore, bariatric surgery, as an efficient therapy for severe obesity, reduces LDN in circulation and improves several components of the metabolic syndrome supporting its recognized anti-inflammatory and beneficial metabolic effects.

FUNDING

This work was supported in part by grants from the National Institutes of Health (NIH; 5P30GM114732-02, P20CA233374 - A. Ochoa and L. Miele), Pennington Biomedical NORC (P30DK072476 - E. Ravussin & LSU-NO Stanley S. Scott Cancer Center and Louisiana Clinical and Translational Science Center (LACaTS; U54-GM104940 - J. Kirwan).

The OLGA-OLGIM staging and the interobserver agreement for gastritis and preneoplastic lesion screening: a cross-sectional study

Stomach cancer (SC) incidence and mortality are relevant public health issues worldwide. In Colombia, screening for preneoplastic lesions (PNL) and the presence of H. pylori is not routinely performed. Therefore, the aim of this study was to evaluate OLGA-OLGIM staging and the interobserver agreement in gastritis and preneoplastic lesions in patients with gastroduodenal symptoms from Colombia. A cross-sectional study was conducted in 272 patients with gastroduodenal symptoms. Gastric biopsies were taken following the Updated Sydney System with the OLGA-OLGIM classification, and the results were evaluated by two pathologists. Chronic gastritis and PNL were reported in 76% and 24% of the patients, respectively. Furthermore, 25% of the patients with PNL displayed gastric atrophy (GA) and 75% intestinal metaplasia (IM). Agreement in the histopathological reading for IM was good, whereas for OLGA was variable, and for the H. pylori quantity was poor. OLGA-OLGIM stages 0-II were the most frequent (96%), while stage III (4%) and SC (4%) were the least frequent. Age and coffee consumption were associated with a higher prevalence of PNL. This work determined that 4% of the population is at high risk of developing SC and would benefit from follow-up studies. Reinforcement of training programs to improve the agreement in histopathology readings is required.

Abstract PO-154: Clinical and prognostic significance of tumor infiltrating lymphocytes of triple negative breast cancer in Colombian women

Background: Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype, represents 10%-20% of all breast cancers and occurs more frequently in young Non- Hispanic Black and Latina women. TNBC is highly immunogenic due to the relatively high levels of tumor infiltrating lymphocytes (TILs) which in turn has been associated with long term survival as well as a risk reduction of death and recurrence. Little is known about TILs and its prognostic value in TNBCs from Latinas such as Colombian women. The goal of this study was to evaluate the differences in the clinic-pathological variables according to TILs levels. Also, to evaluate if TILs are an independent prognostic factor in TNBC from Colombian patients. Methods: We included 130 TNBC patients diagnosed between 2008-2016 at the Colombian National Cancer Institute. Analysis of TILs was performed on a single full-face hematoxylin and eosin (H&E) stained pre-treatment sections. TILs score was estimated as a proportion of intratumoral TILs (iTILs) and stromal TILs (sTILs) on tumoral area and was classified using a cut-off of 10% for sTILs and 1% for iTILs. Additionally, immunohistochemistry for PD-L1 (n=92), CD4 (n=40) and CD8 (n=40) was evaluated on three different fields of vision. Chi-squared test and ANOVA were used to test differences in clinic-pathological variables and Kaplan Meier analysis and long-rank test was used to explore differences in survival according to TILs. Results: High sTILs (≥10%) was observed in 36.4% of the patients. We observed that patients in the high sTILs group were usually diagnosed at early stages and with smaller tumors (&lt;2cm) compared to patients with low sTILs (48.9% vs 23.2%, p&lt;0.01 and 27.3% vs. 5.3%, p&lt;0.01). Regarding treatment, a lower number of patients with high sTILs received neoadjuvant chemotherapy (46.8% vs. 74.4%, p&lt;0.01 and mastectomy (53.2% vs. 74.4%, p=0.02) but had clinical complete response (cCR) (30% vs. 6.2%, p=0.053) compared to patients with low sTILs. Similar results were found for cCR in the iTILs positive group compared to iTILs negative group (13.8% vs. 0%, p&lt;0.01). Differences in overall survival was observed according to sTILs (p&lt;0.01). Cox regression analysis in a model adjusted by AJCC stage found low sTILs (&lt;10%) as a prognostic factor associated with higher risk of death (HR: 1.65, 95% CI 0.99 – 2.77, p=0.05). Stromal and intratumoral CD4 and CD8 were evaluated, and patients were categorized according to the median of expression. For low iCD4 we observed a higher percentage of patients with node involvement (88.9% vs. 52.6%, p=0.04) and for the low iCD8 group we observed larger tumors (&gt;5cm) (47.4% vs. 31.2%, p=0.03). Finally, PD-L1 expression was positive in 21.7% of the patients and was associated with high level of sTILs (p=0.02). Conclusions: Our results suggests that higher levels of sTILs in the TNBC are associated with a better prognosis. Further work is needed to explore the level of CD4, CD8 and PD-L1 expression in our patients to assess its clinical impact.

Citation Format: Carlos A. Huertas, Mayra A. Ramirez, Henry J. Gonzalez, Juan C. Mejía, Laura Fejerman, Jovanny Zabaleta, María C. Sanabria, Silvia J. Serrano. Clinical and prognostic significance of tumor infiltrating lymphocytes of triple negative breast cancer in Colombian women [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-154.

Abstract PO-227: Role of IL-1β pathway in colon cancer progression and its therapeutic implications in African American colon cancer cell lines

Background: Colorectal cancer (CRC) is the third most common cancer and third cause of cancer-related death among African Americans (AA) in the US. When compared to Caucasian Americans (CA), AA patients present with higher incidence and mortality rates for CRC. Recent findings indicate that they have reduced response to the standard of care chemotherapeutic agent 5-Fluorouracil (5-FU) as well as lower frequency of MSI tumors, making them also less likely to respond to conventional immunotherapies. Previous results from human genomic analyses suggest that certain differences seen in AA patients might be due to a decreased antitumor immune response as well as an increased expression of genes involved in inflammatory processes, such as Interleukin-1β (IL-1β). Therefore, we aimed to investigate the role of IL-1β in promoting cell proliferation, cell migration, 5-FU resistance and activation of specific inflammatory pathways in novel AA colon cancer cell lines, and how these responses would compare to well established CA colon cancer cell lines. Methods: Our approach includes using MTS colorimetric assay and Transwell assay to examine the effects of IL-1β treatment on cell proliferation and migration. We performed Western Blot analysis to detect expression of phosphoproteins following treatment with IL-1β. We also investigated how IL-1β affects 5-FU resistance in AA and CA colon cancer cell lines in terms of cell viability. Finally, we tested the ability of IL-1 Receptor antagonist (IL-1Ra) to inhibit the effects of IL-1β on cell proliferation, protein expression, and 5-FU response. Results: Our MTS assay results indicated that cell proliferation in response to IL-1β differs between the AA and the CA colon cancer cell lines, with the AA colon cancer cells being more responsive. Whereas, the migration rate is increased after stimulation with IL-1β for both AA and CA colon cancer cell lines. Protein expression of Phospho-IkB-alpha is increased in AA but not CA colon cancer cell lines following IL-1β treatment, while Phospho-JNK expression was different between the cell lines following treatment. Importantly, our results show that 5-FU efficacy is decreased in the presence of IL-1β for both AA and CA colon cancer cell lines and that treating the cells with IL-1Ra appeared to reestablish 5-FU cell killing effect. IL-1Ra also suppresses the effects of IL-1β on cell proliferation and protein expression. Conclusions: Taken together, our results demonstrated a differential response to IL-1β for the AA colon cancer cell lines, suggesting a probable role played by the cytokine in driving inflammation-related cancer progression and reveals a possible new target to exploit in immunotherapy for this population.

Citation Format: Marzia Spagnardi, Jenny Paredes, Jone Garai, Jovanny Zabaleta, Jennie Williams, Laura Martello-Rooney. Role of IL-1β pathway in colon cancer progression and its therapeutic implications in African American colon cancer cell lines [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-227.

Abstract PO-136: Major signaling pathways associated with biochemical recurrence in Hispanic/Latino patients with prostate cancer

Purpose. A high number of diagnosed prostate cancer (PCa) tumors are indolent and will never become aggressive during a patient's lifetime, however, about 20%-40% will experience post-operative disease relapse with biochemical recurrence (BCR), and a fraction of these will progress towards metastatic disease, which is the leading cause of PCa death. Reliable biomarkers helping in management decision-making and avoiding resistant PCa are still needed. We aimed to identify differentially expressed genes (DEGs) associated with BCR in localized PCa and to explore their involvement in signaling pathways contributing to the progression of PCa in Hispanic/Latino patients. Methods. A total of 117 Hispanic/Latino cases with localized PCa were included. RNA was extracted from FFPE tissues of radical prostatectomy (RP), RNA-seq was performed in 75 cases and used to identify DEGs between BCR positive (BCR) and BCR negative (non-BCR) cases. Signaling pathway analysis was done in MetaCore and DAVID database. DEGs with a p-value &lt; 0.1 were used for enrichment analysis. Results. We identified 21 DEGs between BCR and non-BCR cases, three upregulated and 19 downregulated. From the enriched pathway maps found through MetaCore, the most remarkable pathways related with BCR included metabolism of androgen hormones; differentiation, self-renewal and maintenance of stem cells; mechanisms operating in type 2 diabetes (T2DM) and the cooperative action by pioglitazone and rosiglitazone with metformin; and metabolism of triacylglycerol. In line with these findings, results from DAVID also found Diabetes mellitus as one of the keywords, with downregulation of adiponectin (ADIPOQ) and MCF2L2 as the main genes related to this pathway. Other studies have shown that, regardless of BMI, individuals with T2DM have lower plasma adiponectin levels, which, in turn, are associated with pathophysiological conditions such as obesity, metabolic syndrome and insulin resistance. In our study, BMI was not associated with BCR, however, other complementary measurements related to increased abdominal fat (e.g., waist circumference or waist-to-hip ratio), and with recent evidence of strong association with aggressive PCa, were not assessed by us. Additional pathways associated with BCR progression were those related to biosynthesis and metabolism of androgens, being AKR1C the main gene involved. This gene participates in alternative pathways of the biosynthesis of androgens; for example, downregulated AKR1C leads to the synthesis of dihydrotestosterone and circumvents testosterone as a precursor. Conclusions. Enrichment analyses suggest that pathways related to T2DM and metabolism of androgens are main drivers of BCR in Hispanic/Latino PCa patients, mainly through the downregulation of ADIPOQ and AKR1C. Our findings confirm recent discoveries in the molecular understanding of PCa progression, but more studies analyzing abdominal fat measures in independent and larger cohorts could lead as to more precise conclusions, as well as to identify potential biomarkers and therapeutic targets.

Citation Format: Natalia L. Acosta-Vega, Rodolfo Varela, Jorge Andrés Mesa, Jone Garay, Melody C. Baddoo, Alberto Gómez-Gutiérrez, Silvia J. Serrano-Gómez, Martha Lucía Serrano, Jovanny Zabaleta, Alba L. Combita, María Carolina Sanabria-Salas. Major signaling pathways associated with biochemical recurrence in Hispanic/Latino patients with prostate cancer [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-136.

Obesity and cancer death in white and black adults: A prospective cohort study

OBJECTIVE

This study aimed to determine whether race modifies the association between obesity and cancer death.

METHODS

The Pennington Center Longitudinal Study included 18,296 adults; 35.0% were male and 34.3% were Black. The primary end point was death from cancer.

RESULTS

During a follow-up of 14.3 years, 346 cancer deaths occurred. Among men, race modified the association of BMI and cancer death (p_interaction = 0.045); compared with a BMI of 22 kg/m² , a BMI of 35 in White men was associated with a hazard ratio of 1.74 (95% CI: 1.38-2.21), and in Black men, the hazard ratio was 0.64 (95% CI: 0.45-0.90). Among women, race did not modify the association of BMI and cancer death (p_interaction =0.43); however, compared with a BMI of 22, a BMI of 35 in White women was associated with a hazard ratio of 1.42 (95% CI: 1.18-1.70) and in Black women, the hazard ratio was 0.99 (95% CI: 0.82-1.20).

CONCLUSIONS

In this diverse cohort of adults, having obesity was associated with an increased risk of cancer death in White men and women. In contrast, having obesity was associated with a reduced risk of cancer death in Black men and did not influence risk in Black women.

Severe COVID-19 Is Characterized by an Impaired Type I Interferon Response and Elevated Levels of Arginase Producing Granulocytic Myeloid Derived Suppressor Cells

COVID-19 ranges from asymptomatic in 35% of cases to severe in 20% of patients. Differences in the type and degree of inflammation appear to determine the severity of the disease. Recent reports show an increase in circulating monocytic-myeloid-derived suppressor cells (M-MDSC) in severe COVID 19 that deplete arginine but are not associated with respiratory complications. Our data shows that differences in the type, function and transcriptome of granulocytic-MDSC (G-MDSC) may in part explain the severity COVID-19, in particular the association with pulmonary complications. Large infiltrates by Arginase 1+ G-MDSC (Arg+G-MDSC), expressing NOX-1 and NOX-2 (important for production of reactive oxygen species) were found in the lungs of patients who died from COVID-19 complications. Increased circulating Arg+G-MDSC depleted arginine, which impaired T cell receptor and endothelial cell function. Transcriptomic signatures of G-MDSC from patients with different stages of COVID-19, revealed that asymptomatic patients had increased expression of pathways and genes associated with type I interferon (IFN), while patients with severe COVID-19 had increased expression of genes associated with arginase production, and granulocyte degranulation and function. These results suggest that asymptomatic patients develop a protective type I IFN response, while patients with severe COVID-19 have an increased inflammatory response that depletes arginine, impairs T cell and endothelial cell function, and causes extensive pulmonary damage. Therefore, inhibition of arginase-1 and/or replenishment of arginine may be important in preventing/treating severe COVID-19.

Abstract 2729: Cell infiltration prediction of breast cancer tissues identifies basophils as potentially important immune cells in the tumor microenvironment

Background: Breast cancer (BC) is the most common and deadliest cancer in women worldwide. Hormone receptor (HR) positive tumors (luminal) are the most frequent while HER-2 overexpressing (HR-, HER2+) and triple negative (TNBC, HR-/HER2-) are most deadly. HR+ subtypes are more common in non-Hispanic White women while HER-2 and TNBC present either higher prevalence or risk of mortality in minority groups. Hispanic/Latinos (H/L) is the largest and fastest growing minority in the U.S.A. However, H/L women have been underrepresented in BC studies. We reported that luminal B is the most common BC subtype in a group of H/L and that ERBB2, GRB7 and MIEN1 genes have increased expression in women with higher Indigenous American ancestry. Immune infiltration of tumors has become a hallmark for the prediction of outcome. However, contrary to TNBC, luminal tumors have been considered low immunogenic. Immune infiltration of luminal B tumors in H/L has not yet been investigated. Our goal was to predict immune infiltration of luminal B tumors based on RNA-seq data and according to the levels of body mass index (BMI) and ancestral fractions (West African, European, Indigenous American).

Methods: We performed RNA-seq in 70 luminal B tumors of H/L from Puerto Rico. Ancestry was estimated by genotyping on the Affymetrix U.K. Biobank array and global ancestry proportions determined with Admixture Software v1.3, using 1000 Genomes reference population for anchoring. BMI, age at diagnosis and tumor size were extracted from the Electronic Medical Records. We used Partek Flow for the RNA-seq analysis based on ancestry fraction and BMI. Prediction of cell populations was done in xCell. Correlation analysis was done in GraphPad Prism v7.05.

Results: We found an inverse correlation between Indigenous American and γδ-T cell infiltration (R2= -0.3; p=0.03) while BMI was associated with increased infiltration of basophils (R2=0.3; p=0.026). Among women with high BMI, those with low European ancestry had increased levels of basophils infiltration R2=0.66; p=0.17) and those with high European ancestry had reduced infiltration of naïve CD8+ T cells (R2= -0.53; p=0.008) and reduced plasmacytoid dendritic cells (pDC, R2=-0.51; p=0.01).

Conclusions: We found that luminal B tumors have infiltration of immune cells that may contribute to differences in the response to treatment and outcome. To the best of our knowledge, the role of infiltrating basophils into breast cancer tissues has not been described. However, circulating basophils and predicted infiltration of basophils into ovarian and colorectal cancer tissues have been correlated with survival. Our findings have to be confirmed in a larger set of samples and by additional methods, including immunohistochemistry.

Citation Format: Jone Garai, Julie Dutil, Douglas W. Cress, Victoria Seewaldt, Jamie K. Teer, Laura Fejerman, Lucio Miele, Jovanny Zabaleta. Cell infiltration prediction of breast cancer tissues identifies basophils as potentially important immune cells in the tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2729.

Obesity and Cancer Risk in White and Black Adults: A Prospective Cohort Study

OBJECTIVE

Anthropometric measures of obesity, including BMI and waist circumference (WC), do not quantify excess adiposity and metabolic abnormalities consistently across racial populations. This study tested the hypothesis that participant race modifies the association of anthropometric measures of obesity and cancer risk.

METHODS

This prospective cohort (The Pennington Center Longitudinal Study) included 18,296 adults, 6,405 (35.0%) male sex and 6,273 (34.3%) Black race. The primary exposures were BMI (weight in kilograms/height in meters squared) and WC (centimeters). The primary end point was the time from study enrollment to diagnosis of histologically confirmed invasive cancer.

RESULTS

During a median follow-up of 14.0 years (interquartile range: 9.8-19.0 years), invasive cancer occurred in 1,350 participants. Among men, race modified the association of BMI (P_interaction = 0.02) and WC (P_interaction = 0.01) with cancer incidence; compared with a BMI of 22 kg/m² , a BMI of 35 kg/m² in White men was associated with a hazard ratio of 1.83 (95% CI: 1.58-2.12), whereas in Black men, the hazard ratio was 0.89 (95% CI: 0.72-1.11). Among women, race did not modify the association of BMI (P_interaction = 0.41) or WC (P_interaction = 0.36) with cancer incidence.

CONCLUSIONS

In this diverse cohort of adults, participant race and sex modified the prognostic associations of anthropometric measures of obesity and cancer risk.

Transcriptome and Functions of Granulocytic Myeloid-Derived Suppressor Cells Determine their Association with Disease Severity of COVID-19

COVID-19 ranges from asymptomatic in 35% of cases to severe in 20% of patients. Differences in the type and degree of inflammation appear to determine the severity of the disease. Recent reports show an increase in circulating monocytic-myeloid-derived suppressor cells (M-MDSC) in severe COVID 19, that deplete arginine but are not associated with respiratory complications. Our data shows that differences in the type, function and transcriptome of Granulocytic-MDSC (G-MDSC) may in part explain the severity COVID-19, in particular the association with pulmonary complications. Large infiltrates by Arginase 1 ⁺ G-MDSC (Arg ⁺ G-MDSC), expressing NOX-1 and NOX-2 (important for production of reactive oxygen species) were found in the lungs of patients who died from COVID-19 complications. Increased circulating Arg ⁺ G-MDSC depleted arginine, which impaired T cell receptor and endothelial cell function. Transcriptomic signatures of G-MDSC from patients with different stages of COVID-19, revealed that asymptomatic patients had increased expression of pathways and genes associated with type I interferon (IFN), while patients with severe COVID-19 had increased expression of genes associated with arginase production, and granulocyte degranulation and function. These results suggest that asymptomatic patients develop a protective type I IFN response, while patients with severe COVID-19 have an increased inflammatory response that depletes arginine, impairs T cell and endothelial cell function, and causes extensive pulmonary damage. Therefore, inhibition of arginase-1 and/or replenishment of arginine may be important in preventing/treating severe COVID-19.

Circulating Levels of Sex Steroid Hormones and Gastric Cancer

BACKGROUND AND AIMS

Men develop gastric cancer more frequently than women, yet little is known about the mechanisms underlying this sex difference. Sex steroid hormones may influence gastric cancer risk. We therefore assessed whether major circulating adrenal precursors, androgens and estrogens were associated with gastric cancer in a high-risk Mexican population.

METHODS

Blood samples were collected at time of diagnosis from 50 noncardia gastric cancer patients and 50 histologically confirmed non-atrophic gastritis controls. Serum levels of estradiol, testosterone and dehydroepiandrosterone (DHEA) measured with a validated mass spectrometry method were categorized in tertiles as low (T1), middle (T2), and high (T3). Unconditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI), adjusting for age, sex, and education.

RESULTS

Levels of DHEA were inversely associated with gastric cancer (p-trend per tertile increase: <0.0001), with adjusted ORs (95% CI) of T2 and T3 (vs. T1) of 0.25 (0.09-0.70) and 0.10 (0.03-0.34), respectively. Levels of estradiol and testosterone were not significantly associated with gastric cancer.

CONCLUSIONS

Our study provides evidence that higher concentration of circulating DHEA may be associated with lower risk of noncardia gastric cancer. Longitudinal studies are needed to evaluate the temporality of this association and investigate mechanisms of disease pathogenesis.

Cancer health disparities in racial/ethnic minorities in the United States

There are well-established disparities in cancer incidence and outcomes by race/ethnicity that result from the interplay between structural, socioeconomic, socio-environmental, behavioural and biological factors. However, large research studies designed to investigate factors contributing to cancer aetiology and progression have mainly focused on populations of European origin. The limitations in clinicopathological and genetic data, as well as the reduced availability of biospecimens from diverse populations, contribute to the knowledge gap and have the potential to widen cancer health disparities. In this review, we summarise reported disparities and associated factors in the United States of America (USA) for the most common cancers (breast, prostate, lung and colon), and for a subset of other cancers that highlight the complexity of disparities (gastric, liver, pancreas and leukaemia). We focus on populations commonly identified and referred to as racial/ethnic minorities in the USA-African Americans/Blacks, American Indians and Alaska Natives, Asians, Native Hawaiians/other Pacific Islanders and Hispanics/Latinos. We conclude that even though substantial progress has been made in understanding the factors underlying cancer health disparities, marked inequities persist. Additional efforts are needed to include participants from diverse populations in the research of cancer aetiology, biology and treatment. Furthermore, to eliminate cancer health disparities, it will be necessary to facilitate access to, and utilisation of, health services to all individuals, and to address structural inequities, including racism, that disproportionally affect racial/ethnic minorities in the USA.

Developing new ceramide analogs and identifying novel sphingolipid-controlled genes against a virus-associated lymphoma

Primary effusion lymphoma (PEL) is an aggressive malignancy with poor prognosis even under chemotherapy. Kaposi sarcoma-associated herpesvirus (KSHV), one of the human oncogenic viruses, is the principal causative agent. Currently, there is no specific treatment for PEL; therefore, developing new therapies is of great importance. Sphingolipid metabolism plays an important role in determining the fate of tumor cells. Our previous studies have demonstrated that there is a correlation between sphingolipid metabolism and KSHV+ tumor cell survival. To further develop sphingolipid metabolism-targeted therapy, after screening a series of newly synthesized ceramide analogs, here, we have identified compounds with effective anti-PEL activity. These compounds induce significant PEL apoptosis, cell-cycle arrest, and intracellular ceramide production through regulation of ceramide synthesizing or ceramide metabolizing enzymes and dramatically suppress tumor progression without visible toxicity in vivo. These new compounds also increase viral lytic gene expression in PEL cells. Our comparative transcriptomic analysis revealed their mechanisms of action for inducing PEL cell death and identified a subset of novel cellular genes, including AURKA and CDCA3, controlled by sphingolipid metabolism, and required for PEL survival with functional validation. These data provide the framework for the development of promising sphingolipid-based therapies against this virus-associated malignancy.

Evaluation of deacetylase inhibition in metaplastic breast carcinoma using multiple derivations of preclinical models of a new patient-derived tumor

Metaplastic breast carcinoma (MBC) is a clinically aggressive and rare subtype of breast cancer, with similar features to basal-like breast cancers. Due to rapid growth rates and characteristic heterogeneity, MBC is often unresponsive to standard chemotherapies; and novel targeted therapeutic discovery is urgently needed. Histone deacetylase inhibitors (DACi) suppress tumor growth and metastasis through regulation of the epithelial-to-mesenchymal transition axis in various cancers, including basal-like breast cancers. We utilized a new MBC patient-derived xenograft (PDX) to examine the effect of DACi therapy on MBC. Cell morphology, cell cycle-associated gene expressions, transwell migration, and metastasis were evaluated in patient-derived cells and tumors after treatment with romidepsin and panobinostat. Derivations of our PDX model, including cells, spheres, organoids, explants, and in vivo implanted tumors were treated. Finally, we tested the effects of combining DACi with approved chemotherapeutics on relative cell biomass. DACi significantly suppressed the total number of lung metastasis in vivo using our PDX model, suggesting a role for DACi in preventing circulating tumor cells from seeding distal tissue sites. These data were supported by our findings that DACi reduced cell migration, populations, and expression of mesenchymal-associated genes. While DACi treatment did affect cell cycle-regulating genes in vitro, tumor growth was not affected compared to controls. Importantly, gene expression results varied depending on the cellular or tumor system used, emphasizing the importance of using multiple derivations of cancer models in preclinical therapeutic discovery research. Furthermore, DACi sensitized and produced a synergistic effect with approved oncology therapeutics on inherently resistant MBC. This study introduced a role for DACi in suppressing the migratory and mesenchymal phenotype of MBC cells through regulation of the epithelial-mesenchymal transition axis and suppression of the CTC population. Preliminary evidence that DACi treatment in combination with MEK1/2 inhibitors exerts a synergistic effect on MBC cells was also demonstrated.

Molecular detection of opportunistic pathogens and insights into microbial diversity in private well water and premise plumbing

Private well water systems in rural areas that are improperly maintained will result in poor drinking water quality, loss of water supply, and pose human health risk. The purpose of this study was to investigate the occurrence of fecal indicator bacteria (FIB) and opportunistic pathogens in private well water in rural areas surrounding New Orleans, Louisiana. Our results confirmed the ubiquitous nature of Legionella (86.7%) and mycobacteria (68.1%) in private well water in the study area, with gene concentration ranged from 0.60 to 5.53 and 0.67 to 5.95 Log₁₀ of GC/100 mL, respectively. Naegleria fowleri target sequence was detected in 16.8% and Escherichia coli was detected in 43.4% of the water samples. Total coliform, as well as Legionella and mycobacteria genetic markers' concentrations were significantly reduced by 3-minute flushing. Next-generation sequencing (NGS) data indicated that the abundance of bacterial species was significantly increased in water collected in kitchens compared with samples from wells directly. This study provided integrated knowledge on the persistence of pathogenic organisms in private well water. Further study is needed to explore the presence of clinical species of those opportunistic pathogens in private well water systems to elucidate the health risk.

Immune-Related Gene Expression and Cytokine Secretion Is Reduced Among African American Colon Cancer Patients

Background: Colorectal cancer is the third most deadly cancer among African Americans (AA). When compared to Caucasian Americans (CA), AA present with more advanced disease and lower survival rates. Here, we investigated if differences in tumor immunology could be contributive to disparities observed between these populations.

Methods: We examined gene expression of tumor and non-tumor adjacent tissues from AA and CA by whole transcriptome sequencing, and generated scores for immune cell populations by NanoString. In addition, we utilized “The Cancer Genome Atlas” (TCGA) database from AA and CA as a validation cohort. Finally, we measured the secretion of cytokines characteristic of effector T helper cell (T_h) subsets by ELISA using plasma from each AA and CA participant.

Results: Colon tumors from AA patients showed significant fold-change increase in gene expression when compared to CA for FOXP3 (6.22 vs. 3.22), IL1B (103 vs. 11.4) and IL8 (220 vs. 28.9) (p < 0.05). In contrast, among CA we observed statistically higher gene expression of markers associated with antitumor activity such as GZMB (Granzyme B), IFNG and the immunotherapy targets PDL1 (CD274) and CTLA4 (p < 0.05). TCGA data validated our observed higher gene expression of GZMB and PDL1 in CA patients when compared to AA. Notably, our observations on immune cell populations show that AA tumors have significantly higher number of exhausted CD8+ cells (p < 0.01), mast cells (p < 0.02) and increased T regulatory cells when compared to CA. AA colon cancer patients differed from CA in cytokine production patterns in plasma (i.e., reduced IL-12).

Conclusions: Our study demonstrates significant differences of the immunological profiles of colon tumors from AA compared to CA that suggest a deficiency of appropriate immune defense mechanisms in terms of gene expression, recruitment of immune cells and systemic secretion of cytokines. As such, these immune differences could be mitigated through population-specific therapeutic approaches.

Abstract LB-182: Combination of sulforaphane and 5-aza-2′-deoxycytidine slows the growth and upregulates the chemoattractant CCL5 in metastatic melanoma

UV exposure-induced oxidative stress is implicated as a driving mechanism for melanoma. Increased oxidative stress results in DNA damage and epigenetic dysregulation. We previously found that a low dose of the antioxidant sulforaphane (SFN) in combination with the epigenetic drug 5 –aza –2 ′–deoxycytidine (DAC) slowed cell growth in melanoma at a greater rate than DAC alone. Here, we report a multi –omics analysis with combination and single drug treatment. We observed a significant increase in global protein abundance with an altered level of expression in the combination treatment as compared to individual treatment. Proteins associated with methylation patterns and with reactive oxidative species were found dysregulated in combination treatment. A comparison analysis of proteomic and transcriptomic data with Ingenuity Pathway Analysis showed common canonical pathways involved in phosphorylation (ERK/MAPK signaling) and immune response with combination treatment. The global DNA methylation pattern was analyzed to explore the impact of combination and single drug treatment on methylation status. Interestingly, we observed an increase in the levels of a critical immuno-regulator cytokine, C –C motif ligand 5 (CCL5), which functions as a chemoattractant for natural killer (NK) cells. Animal studies showed the level of CCL5in blood and tumor was increased with DAC and SFN combination treatment compared to that of control, which coincided with tumor reduction. Our data demonstrate the impact of SFN on the effectiveness of the FDA –approved drug DAC to reduce metastatic melanoma tumors.

Citation Format: Tung-Chin Chiang, Brian Koss, Aaron J. Storey, Jovanny Zabaleta, Samrat Roy Choudhury, Bradley D. Shields, Elizabeth C. Draper, L Joseph Su, Alan J. Tackett. Combination of sulforaphane and 5-aza-2′-deoxycytidine slows the growth and upregulates the chemoattractant CCL5 in metastatic melanoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-182.

Abstract 6691: Delivering intra-tumoral immune modulators and targeting cancer stem cells using recombinant- AAVs

Solid tumors are composed of heterogeneous cell populations that support rapid growth of cancer cells and suppress immune cell responses. Unleashing the body's own immune response to eradicate cancer cells is one of the most promising ways to treat cancer patients. However, cancer immunotherapy is not without challenges. Some of these include:

1) Phenotypic plasticity and clonal selection in a highly dynamic, heterogeneous and mutable cell population, which leads to de novo and acquired resistance;

2) Immune editing by cancer cells;

3) Expression of immune check point ligands and receptors to suppress immune response locally within the tumor microenvironment, and systemically using exosomes as immune checkpoint carriers;

4) Cross-talk between cancer stem cells and the immune microenvironment;

5) Feasibility of developing personalized treatment strategies, such as cost vs benefit of CAR-T-cell therapy and time constraint, and humanized antibody production;

6) Systemic toxicity of current immunotherapy strategies;

To address these challenges, we propose to use a recombinant adeno-associated virus (rAAV) platform to simultaneously enhance tumor immunity and target cancer stem cells by intra-tumoral administration. We express programmed cell death ligand-1 (PD-L1), and B7-H3 (CD276), in combination with a Notch1 decoy. The latter was chosen because: 1) Notch is a crucial signaling component of cancer stem cells (CSCs) maintenance and resistance and 2) Studies have shown that within the tumor, regulatory T-cells (Treg) are activated by OX40 and Notch ligand Jagged1. Blocking Notch signaling would have dual advantages: blocking Notch signaling in CSCs, and preventing activation of immunosuppressive Tregs.

Based on current clinical trials and our experimental results, we hypothesized that intra-tumoral injection of rAAV viral particles engineered to express soluble PD-1, B7-H3 and Notch1 decoys in combination with lipopolysaccharide (LPS) is a promising strategy. To test our hypothesis, we used two mouse triple negative breast (TNBC) cancer models: C0321 in the FVB background and M-Wnt in the C57/Bl6 background; both are aggressive, highly metastatic, and similar to human TNBC. Using tumor spheroids in vitro, in the presence of soluble decoys of PD-1, B7-H3 and Notch1 synergistically induced the most effective tumor cell killing, compared to single decoy application. Importantly, intra-tumoral injection of PD-1, B7-H3 and Notch1 decoys in combination with LPS induced necrosis of tumors in vivo in our preliminary findings.

Citation Format: Deniz A. Ucar, Giulia Monticone, Fokhrul Hossain, Samarpan Majumder, Dorota Wyczechowska, Matthew J. Dean, Luis Del Valle, Jovanny Zabaleta, Yong Ran, Sudarvili Shanthalingam, Abraham Bert Chabot, Bridgette M. Collins-Burow, Matthew E. Burrow, Barbara Osborne, Todd Eliot Golde, Lucio Miele. Delivering intra-tumoral immune modulators and targeting cancer stem cells using recombinant- AAVs [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6691.

Abstract 4615: Admixture mapping and gene expression analysis to identify candidate genes associated with HER2 positive breast cancer in Latinas

The incidence of Human Epidermal Growth Factor Receptor 2 positive (HER2+) breast cancer is higher in Latinas, both in the U.S. and in Latin America. Preliminary analyses of the Peruvian Genetics and Genomics of Breast Cancer (PEGEN-BC) study data set showed a strong association between the Indigenous American (IA) component of ancestry and HER2 status independently of stage at diagnosis and other factors. The aim of this study was to identify genetic loci associated with genetic ancestry and HER2+ breast cancer in patients with high IA ancestry. To achieve this aim we used admixture mapping and gene-expression guided fine mapping.

Breast cancer patients were recruited at the Instituto Nacional de Enfermedades Neoplásicas in Lima, Peru. A total of 1,850 patients have been recruited to date. DNA samples are currently available for a total of 1,380 patients. Genome wide genotypes were obtained with the Affymetrix Precision Medicine Research Array. After quality control, genome wide genotype data was available for 1,312 patients. After LD pruning and exclusion of SNPs with minor allele frequency &lt;0.05, we estimated global ancestry with the program ADMIXTURE and locus-specific ancestry using RFMix. Tumor subtypes were classified using immunohistochemistry markers for estrogen, progesterone and HER2 receptors. Admixture mapping was conducted using logistic regression models. The outcome variable was HER2 status (HER2+ =1, HER2- =0). Global Individual IA ancestry and age at diagnosis were included as covariates. For transcriptomic analysis within regions of interest we used exome sequencing data (Illumina NextSeq500 system) for total RNA extracted from 79 FFPE tumor tissues from the same cohort. Genes within regions with suggestive admixture mapping signals were further analyzed by comparing normalized RNA read counts by HER2+ status using the DEseq2 R package.

Admixture mapping analysis revealed two regions associated with IA ancestry in two chromosomal regions: 2q11-2q12 (OR=0.6, p=0.00009) and 3p14 (OR=1.5, p= 0.0004). Of the 44 genes within the 2q region, TGFBRAP1, member of the heat shock protein 90 family, was the only gene with suggestive differential expression by HER2 status (p=0.032). Of the 28 genes within the 3p14 region, we found significant differential expression for FLNB (lower expression in HER2+ tumours, 5%FDR= 0.03), which has been shown to supress tumour growth and metastasis.

Combining admixture mapping and transcriptomics is a promising approach to discover candidate genes associated with subtype-specific breast cancer risk. We are currently working to replicate suggestive findings and expand our sample size to increase power.

Citation Format: Valentina Zavala, Katie M. Marker, Tatiana Vidaurre, Jeannie Navarro-Vasquez, Sandro Casavilca, Mónica Calderon, Julio Abugattas, Henry Gómez, Hugo Fuentes, Ruddy Liendo-Picoaga, Jose M. Cotrina, Silvia P. Neciosup, Carlos A. Castaneda, Zaida Morante, Fernando Valencia, Silvia J. Serrano-Gomez, Jovanny Zabaleta, Laura Fejerman. Admixture mapping and gene expression analysis to identify candidate genes associated with HER2 positive breast cancer in Latinas [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4615.

Abstract 267: microRNA expression analysis in hrHPV positive FFPE tissues for the detection of cervical disease

Cervical cancer ranks first in cancer mortality among women of low-middle income countries where 80% of the 570,000 cases and 311,000 worldwide deaths estimated for 2018 occurred. Persistent infections with high-risk HPV (hrHPV) genotypes can lead to cervical high-grade lesions (Cervical Intraepithelial Neoplasia grade 2 or more severe disease, CIN-II+), that if left untreated progress to cancer. hrHPV test has high sensitivity but because many women infected with hrHPV genotypes will clear the infection spontaneously, it has low specificity to detect CIN-II+. MicroRNAs (miRNAs) are small RNAs that regulate gene expression and show differential profiles in cervical intraepithelial lesions. Our aim was to identify miRNAs differentially expressed in CIN-II+ and to evaluate their potential use as biomarkers to distinguish low from high-grade lesions in hrHPV positive women. Methods We compared the miRNAs expression pattern between Formalin-Fixed Paraffin-Embedded (FFPE) tissues from hrHPV positive women with low-grade lesions (n=10) and women with high-grade lesions (n=10) of Medellin, Colombia, using the QIAseq miRNA Library Kit (Qiagen) and sequencing reagents and protocols from Illumina. The miRNAs with low coefficient of variation and high fold change were further validated by RT-PCR (miR-133a-3p, 143-3p, 143-5p, 29a-3p and 30b-5p) using miRCURY LNA miRNA PCR kit (Qiagen) and SNORD44 as housekeeping gene. Receiver Operating Characteristic (ROC) analyses with 95% confidence interval of the area under the curve were used to evaluate the diagnostic accuracy of the 5 miRNA and their combinations and the maxim Youden index to determine the optimal specificity and sensitivity. Results The differential miRNAs expression analysis identified 25 miRNAs overexpressed in high- versus low-grade lesions. The relative expression by RT-PCR of 5 of those miRNAs was higher in high-grade when compared to low-grade, and the levels of miR-143-3p, 143-5p and 30b-5p increased with disease progression (from healthy, CIN-I, CIN-II, CIN-III+). ROC analyses showed that miR-143-5p and the combination with miR-133a-3p exhibits the highest AUC 79% (95% CI: 65-93). However, the highest sensitivity is given by miR-29a-3p, 87.50% (95% CI: 67.64 - 97.34), and the highest specificity is given by miR-30b-5p, 95.45% (95% CI: 77.16-99-88), with cut-offs of &gt;1,157 and &gt;3,345 respectively. In conclusion, we identified 25 candidate miRNAs biomarkers and validated 5 of them with good diagnostic performance to distinguish high-grade from low-grade cervical lesions. Further validation on a larger cohort of samples is needed to confirm the potential role of these microRNAs to triage HPV positive women.

Citation Format: Martha I. Gonzalez, Jone Garai, Jovanny Zabaleta, Gloria I. Sanchez. microRNA expression analysis in hrHPV positive FFPE tissues for the detection of cervical disease [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 267.