Adolescent Young Adult Hodgkin Lymphoma Research Articles

Differential Gene Expression in Circulating T-Cells in Long-Term Adolescent/Young Adult Hodgkin Lymphoma (AYAHL) Survivors and Their Unaffected Twins

Background: We and others have demonstrated persistent differences in T cell function and cytokine responses in adolescent/ young adult Hodgkin lymphoma (AYAHL) survivors and their family members. To identify the transcription control pathways involved, we examined mRNA profiles from 17 pairs of long term AYA HL survivors and their unaffected twins.Methods: Blood samples were collected remotely from AYAHL survivors and their like-sex unaffected co-twin controls and shipped to the Epeldegui laboratory at UCLA. B and T cells were negatively separated using magnetic beads. RNA was extracted and sequenced using a high-efficiency mRNA-targeted assay system (Lexogen QuantSeq 3' FWD), with an average 6.7 million reads per sample mapped to the hg38 human transcriptome (99%) using the STAR aligner. Raw read counts for each gene transcript were normalized to transcripts per million total mapped reads and log2 transformed for analysis using linear statistical models including a random effect of twin pair. Analyses examined average expression of pre-specified sets of 17 genes in general immunologic activation (i.e., AP-1- and NF-kB-family transcripts) and 28 Type I IFN-responsive genes (e.g., IFI-, OAS-, and MX-family), as well as TELiS promoter-based bioinformatics analyses of all genes showing >2-fold empirical differences in gene expression (focusing on activation-induced transcription factors, NF-kB and AP-1, and Type 1 interferon-related IRF transcription factors). Body mass index, history of therapeutic radiation, zygosity, sex, age at diagnosis and age at blood collection were included in the model.Results: The average age at diagnosis was 25 years with blood collected 33 years post-diagnosis. In T-cells, AYAHL survivors showed marginally lower expression of 12 activation-induced genes (average 0.41-fold, p = .038) and markedly lower expression of 28 Type 1 interferon-related genes (average 0.33-fold, p < .001) relative to their unaffected co-twins. B cells showed similar reductions in activation-induced genes (0.33-fold, p < .001) but no difference in Type 1 interferon genes (1.02-fold, p =. 942). Promoter-based bioinformatics analyses of all 151 genes found to be differentially expressed by >2-fold in T cells between AYAHL survivors and their unaffected co-twin controls implicated IRF-family transcription factors in mediating observed differences, with IRF3 showing the most significant signal of decreased activity (0.68-fold, p = .059). We also identified marked up-regulation of multiple GATA family transcription factors (GATA3: p < .001; GATA1: p = .009; GATA2: p = .032).Conclusions: Transcriptional indicators of immunologic activation and Type 1 interferon activity show persistent down-regulation in T lymphocytes from long-term adult AYAHL survivors compared to their unaffected like-sex co-twin controls. Incidental findings also identified persistent activation of other gene regulatory pathways mediating T-cell differentiation (e.g., GATA family). We have previously demonstrated higher Epstein-Barr virus (EBV) copy number in AYAHL long-term survivors compared to their unaffected co-twin controls, as well as lower levels of circulating interleukin-12, consistent with a decrease in the ability to control viral replication. The GATA family plays a major role in commitment to T cell lineage (GATA3) and upregulation of the T-helper-type 2 response, and possibly in control of EBV viral infection (GATA2), processes relevant to AYAHL. These differences further support the premise that abnormalities in T-cells play a strong role in etiology, pathogenesis, and survivorship. DisclosuresNo relevant conflicts of interest to declare.

Past Infection and Risk of Adolescent/Young Adult Hodgkin Lymphoma

Background: Adolescent/young adult (AYA) Hodgkin lymphoma (HL) is one of the most common cancers in this age group in developed countries. High socioeconomic status, small sibship size and lack of crowding in childhood are risk factors. We also found that among twins, the twin who had more oral exposures in early life was 80% less likely to develop AYA Hodgkin lymphoma. These risk factors are compatible with the hygiene hypothesis. We wanted to further explore additional risk factors consistent with this etiologic model. Methods: In a case-family control study, we examined past exposure to 12 infections in serum samples from 291 AYA HL cases and 194 of their unaffected family members. Cases were ascertained from the USC International Twin Registry (n=36) and the USC Cancer Surveillance Program (n=255). We measured antibodies to HSV1, HSV2, VZV, EBV, HHV7, HCMV, HHV6, KSHV, T. gondii, H. pylori, Rubella virus and Parvovirus B19 using a multiplex serology bead array (Luminex) (Waterboer Laboratory, German Cancer Research Center). A positive history of exposure to each infection was determined by a titer threshold specific for each infection. We did not examine the association between antibody levels and risk because of the possible impact of AYA HL diagnosis or treatment. We made the assumption that disease or treatment would not affect detection of a low level of antibody indicating previous exposure. A logistic regression model was used to calculate the odds ratio (OR) and 95% Confidence Interval (95% CI) adjusting for age at blood draw, sex and family. The sample was mostly non-Hispanic white, thus we did not adjust for race/ethnicity. We performed stratified analysis for histologic subtype where possible. Linear regression was used to calculate the p-for trend for 0, 1 or 2 fecal-oral or respiratory infections, with 0 infections as the reference. Results: The mean age at diagnosis in AYA HL cases was 30 years and the mean age at blood draw was 36 years. 57% of the cases were female. Out of the 186 cases with EBV tumor status, 78% were EBV-. Out of the 242 cases with histologic subtype, 72.5% were nodular sclerosis. The mean age of the 194 family controls at blood draw was 53 years and 63.4% were female. Evidence of past HHV6 infection was associated with an increased risk of AYA HL (OR= 1.80; 95% CI= 1.06-3.07; for nodular sclerosis only: OR= 1.92, 95% CI=1.05-3.42). Having antibodies to H. pylori was associated with a decreased risk (OR= 0.49; 95% CI= 0.25-0.98; for nodular sclerosis only: OR= 0.33, 95% CI= 0.14-0.77). An increasing number of fecal-oral infections (H. pylori, T. gondii) was associated with a decreasing risk of AYA HL (ptrend=0.015), while an increasing number of respiratory transmitted infections (Rubella virus, Parvovirus) was not significantly associated (ptrend=0.43). After adjusting for family, infection with Parvovirus was strongly and significantly associated with AYA HL (OR=3.8,1.06-13.6; for nodular sclerosis only: OR=10.5, 95% CI=1.71-65.25). Past infection with EBV was not associated with risk of overall HL, or with EBV- or EBV+ AYA HL separately, probably because of the high frequency of this infection in the overall population. Conclusions: We found continuing evidence for an inverse association between fecal-oral transmitted agents and risk of AYA HL, supporting the hypothesis that a deficit of early life fecal-oral transmitted microbes may be associated with susceptibility. HHV6 and Parvovirus were associated with an increased risk, possibly due to a subclinical immune deficiency or another unknown mechanism Disclosures No relevant conflicts of interest to declare.

Abstract PO-44: Past infection and risk of adolescent/young adult HL

Abstract Background: Adolescent/young adult (AYA) Hodgkin lymphoma (HL) risk is increasingly linked to a deficit of microbial exposure in early life, especially from fecal-oral transmission. Methods: In this cross-sectional study, we examined past exposure to 15 infections in serum samples from 291 AYA HL cases and 194 of their unaffected family members. We measured antibodies to HSV1, HSV2, VZV, EBV, HHV7, HCMV, HHV6, KSHV, S. gallolyticus, F. nucleatum, T. gondii, H. pylori, Rubella virus, and Parvovirus B19 using a multiplex serology bead array (Luminex). A positive history was determined by a titer threshold specific for each infection. A logistic regression model was used to calculate the odds ratio (OR) of AYA HL risk for each infection separately adjusted for sex and age at sampling. We then applied the same logistic regression model, adding an adjustment for family. Results: Evidence of past HHV6 infection was associated with an increased risk of AYA HL (OR= 1.80; 95% CI= 1.06-3.07). Having antibodies to H. pylori was associated with a decreased risk (OR= 0.49; 95% CI= 0.25-0.98). An increasing number of fecal-oral infections (H. pylori, T. gondii) was associated with a decreasing risk of AYA HL (ptrend&amp;lt;0.001), while an increasing number of respiratory-transmitted infections (Rubella virus, Parvovirus) was not significantly associated (ptrend=0.062). After adjusting for family, infection with Parvovirus was the only significant risk factor for AYA HL (OR=3.8,1.06-13.6). Conclusions: We show preliminary evidence for an inverse association between fecal-oral transmitted agents and risk of AYA HL, supporting the hypothesis that a deficit of early life fecal-oral transmitted microbes may be associated with increased risk. HHV6 and Parvovirus were associated with an increased risk, possibly due to a subclinical immune deficiency or an unknown mechanism. In the final presentation, we will add data from 40 additional unaffected family members currently missing age, and results by histology and EBV status. Citation Format: Maryam Saleh, Amie Hwang, Julia Simon, Thomas M. Mack, Tim Waterboer, Wendy Cozen. Past infection and risk of adolescent/young adult HL [abstract]. In: Proceedings of the AACR Virtual Meeting: Advances in Malignant Lymphoma; 2020 Aug 17-19. Philadelphia (PA): AACR; Blood Cancer Discov 2020;1(3_Suppl):Abstract nr PO-44.

DNA methylation patterns of adult survivors of adolescent/young adult Hodgkin lymphoma compared to their unaffected monozygotic twin

DNA methylation (DNAm) silences gene expression and may play a role in immune dysregulation that is characteristic of adolescent/young adult Hodgkin lymphoma (AYAHL). We used the Infinium HumanMethylation27 BeadChip to quantify DNAm in blood (N = 9 pairs, mean age 57.4 y) or saliva (N = 36 pairs, mean age 50.0 y) from long-term AYAHL survivors and their unaffected co-twins. Epigenetic aging (DNAm age) was calculated using previously described methods and compared between survivors and co-twins using paired t-tests and analyses were stratified by sample type, histology, sex, age at sample collection and time since diagnosis. Differences in blood DNAm age were observed between survivors and unaffected co-twins (64.1 vs. 61.3 years, respectively, p = .04), especially in females (p = .01); no differences in saliva DNAm age were observed. Survivors and co-twins had 74 (in blood DNA) and 6 (in saliva DNA) differentially methylated loci. Our results suggest persistent epigenetic aging in AYAHL survivors long after HL cure.

Fecal microbiota diversity in survivors of adolescent/young adult Hodgkin lymphoma: a study of twins.

Background:Adolescent/young adult Hodgkin lymphoma (AYAHL) survivors report fewer exposures to infections during childhood compared with controls, and they have functional lymphocyte aberrations. The gut microbiota plays a central role in immunity.Methods:We investigated whether fecal microbial diversity differed between 13 AYAHL survivors and their unaffected co-twin controls. Pyrosequencing of fecal bacterial 16S rRNA amplicons yielded 252 943 edited reads that were assigned to species-level operational taxonomic units (OTUs) and standardised for sequencing depth by random sampling. Microbial diversity was compared within vs between twin pairs and by case–control status.Results:The number of unique OTUs was more similar within twin pairs compared with randomly paired participants (P=0.0004). The AYAHL cases had fewer unique OTUs compared with their co-twin controls (338 vs 369, P=0.015); this difference was not significant (169 vs 183, P=0.10) when restricted to abundant OTUs.Conclusion:In this small study, AYAHL survivors appear to have a deficit of rare gut microbes. Further work is needed to determine if reduced microbial diversity is a consequence of the disease, its treatment, or a particularly hygienic environment.

Fecal Microbiota Diversity in Survivors of Adolescent/Young Adult Hodgkin Lymphoma

AbstractAbstract 1533Survivors of adolescent/young adult Hodgkin lymphoma (AYAHL) report fewer exposures to infections during childhood compared to controls. They also have persistent genomic and functional aberrations in their lymphocytes that are partially attributable to chemotherapy or radiotherapy. Recent studies have shown that the gut microbiome can affect both the innate and adaptive immune response, and can suppress or exacerbate an inflammatory response. Given the central role of the gut microbiota in immune function, we investigated whether AYAHL survivors, who were members of 13 mono- and dizygotic twin pairs discordant for this disease, have differences in the diversity or phylogenetic configurations of their fecal microbiota compared to their unaffected co-twins. Twin pairs discordant for AYAHL are an ideal study population because they are at least partially matched on genetic and early life factors, both of which influence the composition of the gut microbiome.Pyrosequencing of bacterial 16S rRNA amplicons generated from single fecal samples obtained from each individual yielded 253,182 filtered and de-noised reads translated into species-level operational taxonomic units (OTUs). Standardized across individuals by random sampling, reads were assigned to 2513 OTUs to compare microbiome diversity and relative abundance of taxa. The number of OTU’s was compared between twins using a paired student’s t-test and a one-way analysis of variance was performed to determine whether such measures differed across twin pairs by comparing the measures between twins to those of randomly paired individuals. AYAHL survivors had less diverse fecal microbial communities compared to their unaffected co-twin controls by all measures of alpha diversity (Table 1). Measures that weighted the relative abundance of the bacteria were not statistically significantly different (Shannon Index, p= 0.270; Chao index, p= 0.066, PD Whole Tree Index, p= 0.051). However, when the unweighted number of unique OTUs was considered, the difference was significant (338 in cases vs. 369 in unaffected co-twin controls, p= 0.015). When the analysis was restricted to OTUs that were present at an abundance of > 0.1% in at least 2 of the 23 samples analyzed, the differences were attenuated, with only the PD Whole Tree index difference in diversity remaining marginally significant (p= 0.045). Only one bacterial taxon was associated with AYAHL, probably due to chance. Phylogenetic measurements indicated that the bacterial component of the microbiota of co-twins were more similar with respect to one another than unrelated individuals, although no differences by zygosity were observed. These results provide evidence that AYAHL survivors have reduced diversity of the gut microbiota, perhaps as a consequence the disease, its treatment, or a particularly hygienic environment.Table 1Comparisons of alpha diversity measurements between Hodgkin lymphoma cases and co-twin controls.Measurements of Alpha DiversityMean (Cases)Mean (Unaffected Co-twins)Mean Difference (Unaffected co-twin-case difference)P-value1Initial analysisNo. unique OTUs338369310.015Shannon index5.65.80.20.27Chao1533574410.066PD_whole tree21.222.81.60.051Conservative analysisNo. unique OTUs183196130.10Shannon index5.25.40.20.40Chao123023770.47PD_whole tree13.714.60.90.0451P-value by paired t-tests. Disclosures:No relevant conflicts of interest to declare.