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D'Angelo, C. R.

Publications and source records attributed to D'Angelo, C. R..

3 recordsLinked to original sources

Impact of high-fat Western diet on chronic lymphocytic leukemia disease progression and gut microbiome profile in Eμ-TCL1 mice

BackgroundThe composition and function of the gut microbiome have been shown to contribute to both health and disease. One of the most powerful modulators of microbial composition and function is diet. Materials & MethodsUsing the E{micro}-TCL1 murine model of B-cell chronic lymphocytic leukemia (CLL), we assigned male and female mice to a high-fat, high-carbohydrate Western diet (HF) or standard chow (CH) diet. ResultsMice consuming a HF diet had significantly shorter survival than those consuming a CH diet, irrespective of sex, with female mice exhibiting particularly poor outcomes. We also observed a significant increase in splenic involvement by CLL in the HF diet-fed mice at time of sacrifice. Mice receiving the HF diet demonstrated immediate and profound effects on the gut microbiome, marked by reduced alpha diversity and significantly different community composition as measured by beta diversity. Notably, there was a sustained increase in Akkermansia muciniphila and Bacteroidetes thetaiotaomicron in HF diet-fed mice, coupled with a corresponding increase in microbiome functional pathways related to arginine and histidine biosynthesis, chitin degradation, and nucleotide biosynthesis. DiscussionCollectively our data provides evidence of the profound and sustained impact of a high-fat Western diet upon the gut microbiome community and CLL pathogenesis in the E{micro}-TCL1 murine model of CLL.

cancer biology↗

Novel spirocyclic dimer, SpiD3, targets chronic lymphocytic leukemia survival pathways with potent preclinical effects

Chronic lymphocytic leukemia (CLL) cell survival and growth is fueled by the induction of B-cell receptor (BCR) signaling within the tumor microenvironment (TME) driving activation of NF- {kappa}B signaling and the unfolded protein response (UPR). Malignant cells have higher basal levels of UPR posing a unique therapeutic window to combat CLL cell growth using pharmacological agents that induce accumulation of misfolded proteins. Frontline CLL therapeutics that directly target BCR signaling such as Bruton-tyrosine kinase (BTK) inhibitors (e.g., ibrutinib) have enhanced patient survival. However, resistance mechanisms wherein tumor cells bypass BTK inhibition through acquired BTK mutations, and/or activation of alternative survival mechanisms have rendered ibrutinib ineffective, imposing the need for novel therapeutics. We evaluated SpiD3, a novel spirocyclic dimer, in CLL cell lines, patient-derived CLL samples, ibrutinib-resistant CLL cells, and in the E{micro}-TCL1 mouse model. Our integrated multi-omics and functional analyses revealed BCR signaling, NF-{kappa}B signaling, and endoplasmic reticulum stress among the top pathways modulated by SpiD3. This was accompanied by marked upregulation of the UPR and inhibition of global protein synthesis in CLL cell lines and patient-derived CLL cells. In ibrutinib-resistant CLL cells, SpiD3 retained its anti-leukemic effects, mirrored in reduced activation of key proliferative pathways (e.g., PRAS, ERK, MYC). Translationally, we observed reduced tumor burden in SpiD3-treated E{micro}-TCL1 mice. Our findings reveal that SpiD3 exploits critical vulnerabilities in CLL cells including NF-{kappa}B signaling and the UPR, culminating in profound anti-tumor properties independent of TME stimuli. STATEMENT OF SIGNIFICANCESpiD3 demonstrates cytotoxicity in CLL partially through inhibition of NF-{kappa}B signaling independent of tumor-supportive stimuli. By inducing the accumulation of unfolded proteins, SpiD3 activates the UPR and hinders protein synthesis in CLL cells. Overall, SpiD3 exploits critical CLL vulnerabilities (i.e., the NF-{kappa}B pathway and UPR) highlighting its use in drug-resistant CLL. VISUAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=137 HEIGHT=200 SRC="FIGDIR/small/578283v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@1dd7a38org.highwire.dtl.DTLVardef@1831c85org.highwire.dtl.DTLVardef@c571f9org.highwire.dtl.DTLVardef@bdce53_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

A novel triple-action inhibitor targeting B-cell receptor signaling and BRD4 demonstrates preclinical activity in chronic lymphocytic leukemia

B-cell chronic lymphocytic leukemia (CLL) results from intrinsic genetic defects and complex microenvironment stimuli that fuel CLL cell growth through an array of survival-signaling pathways. Novel small-molecule agents targeting the B-cell receptor pathway and anti-apoptotic proteins alone or in combination have revolutionized the management of CLL, yet combination therapy carries significant toxicity and CLL still remains an incurable disease due to residual disease and relapse. Single-molecule inhibitors that can target multiple disease-driving factors are thus an attractive approach to combat both drug resistance and combination therapy-related toxicities. Using SRX3305, a novel small-molecule BTK/PI3K/BRD4 inhibitor that targets three distinctive facets of CLL biology, we demonstrate that SRX3305 attenuates CLL cell proliferation and promotes apoptosis in a dose-dependent fashion. SRX3305 also inhibits activation-induced proliferation of primary CLL cells in vitro, and effectively blocks microenvironment-mediated survival signals including stromal cell contact. Furthermore, SRX3305 blocks CLL cell migration toward CXCL-12 and CXCL-13, major chemokines involved in CLL cell homing and retention in microenvironment niches. Importantly, SRX3305 maintains its anti-tumor effects in ibrutinib-resistant CLL cells. Collectively, this study establishes the preclinical efficacy of SRX3305 in CLL providing significant rationale for its development as a therapeutic agent for CLL and related disorders.

cancer biology↗