RESUMO
The exchange of genes between cells is known to play an important physiological and pathological role in many organisms. We show that circulating tumor DNA (ctDNA) facilitates cell-specific gene transfer between human cancer cells and explain part of the mechanisms behind this phenomenon. As ctDNA migrates into the nucleus, genetic information is transferred. Cell targeting and ctDNA integration require ERVL, SINE or LINE DNA sequences. Chemically manufactured AluSp and MER11C sequences replicated multiple myeloma (MM) ctDNA cell targeting and integration. Additionally, we found that ctDNA may alter the treatment response of MM and pancreatic cancer models. This study shows that retrotransposon DNA sequences promote cancer gene transfer. However, because cell-free DNA has been detected in physiological and other pathological conditions, our findings have a broader impact than just cancer. Furthermore, the discovery that transposon DNA sequences mediate tissue-specific targeting will open up a new avenue for the delivery of genes and therapies.
Assuntos
DNA Tumoral Circulante , Elementos de DNA Transponíveis , Humanos , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Elementos de DNA Transponíveis/genética , Linhagem Celular Tumoral , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Animais , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Camundongos , Especificidade de Órgãos/genética , Retroelementos/genética , Técnicas de Transferência de GenesRESUMO
BACKGROUND: Chemotherapy adversely affects physical well-being and inflammation may be related to changes in physical well-being. We evaluated the association of systemic inflammation with changes in physical well-being. METHODS: In a prospective study of 580 patients with stages I-III breast cancer we assessed immune cell counts, neutrophil:lymphocyte ratio (NLR), lymphocyte:monocyte ratio (LMR), and platelet:lymphocyte ratio (PLR) within 7 days before chemotherapy (pre-chemotherapy). Physical well-being was assessed using the Functional Assessment of Cancer Therapy: General-Physical Well-being subscale (FACT-PWB) pre-chemotherapy and 1 month and 6 months post-chemotherapy. Clinically meaningful decline in physical well-being was determined as decreasing FACT-PWB by more than one point from pre-chemotherapy level, and non-resilience defined as having decline post-chemotherapy and not returning to within one-point of pre-chemotherapy FACT-PWB by 6 months post-chemotherapy. Multivariable logistic regressions examined the association between inflammation and changes in physical well-being, adjusting for sociodemographic and clinical characteristics. RESULTS: Fifty-nine percent (310/529) and 36% (178/501) of participants had physical well-being decline post-chemotherapy and 6 months post-chemotherapy, respectively. Fifty percent (147/294) were non-resilient. Low NLR and PLR were associated with 1.78 (Pâ =â .01) and 1.66 (Pâ =â .02) fold greater odds of having a decline in physical well-being 6 months post-chemotherapy compared to those with high NLR and PLR, respectively. Low NLR and PLR were associated with 1.92 (Pâ =â .02) and 2.09 (Pâ =â 0.01) fold greater odds of being non-resilient 6 months post-chemotherapy compared to those with high NLR and PLR, respectively. CONCLUSION: Low NLR and PLR were associated with chemotherapy-induced changes in physical well-being independent of sociodemographic and clinical risk factors.
RESUMO
Tumor necrosis factor (TNF)α is a major regulator of inflammation. However, the epigenetic regulation of TNFα in the context of an exercise intervention among older adults with cancer is understudied. In this exploratory analysis, we used data from a single-arm mobile health (mHealth) exercise intervention among older adults with myeloid malignancies to 1) assess changes in TNFα promoter methylation, TNFα mRNA expression, serum TNFα and other related-cytokine levels after intervention; and 2) assess correlations between blood markers and exercise levels. Twenty patients were included. From baseline to post-intervention, there was no statistical changes in TNFα promoter methylation status at seven CpG sites, TNFα mRNA expression, and serum TNFα levels. Effect sizes, however, were moderate to large for several CpG sites (-120, -147, -162, and -164; Cohen's d = 0.44-0.75). Median serum TNFα sR1 levels increased (83.63, IQR 130.58, p = 0.06; Cohen's d = 0.18) but not the other cytokines. Increases in average daily steps were correlated with increases in TNFα promoter methylation at CpG sites -147 (r = 0.48; p = 0.06) and -164 (r = 0.51; p = 0.04). Resistance training minutes were negatively correlated with TNFα promoter methylation at CpG site -120 (r = -0.62; p = 0.02). All effect sizes were moderate to large. In conclusion, after a mHealth exercise intervention, we demonstrated changes with moderate to large effect sizes in several CpG sites in the TNFα promoter region. Exercise levels were correlated with increases in TNFα promoter methylation. Larger exercise trials are needed to better evaluate TNFα regulation to inform interventions to augment TNFα regulation in order to improve outcomes in older adults with cancer.