Abstract CT549: Randomized Phase II trial of two different nutritional approaches for patients receiving treatment for their advanced pancreatic cancer

Background: Pancreatic ductal adenocarcinoma (PDAC) is characterized by stromal fibrosis, hypoxia, and nutritional deprivation. PDAC tumors grow aggressively, diagnosis is typically made after metastasis and the disease remains associated with poor outcomes. The triplet chemotherapy regimen of gemcitabine, nab-paclitaxel with cisplatin was associated with a median overall survival of 16.4 months in patients with metastatic pancreatic cancer in the first-line setting (Jameson et al., 2020). Nutritional, metabolic interventions offer an opportunity to fundamentally change the tumor microenvironment and improve outcomes for patients. A medically supervised ketogenic diet (MSKD) defined as lower carbohydrate, lower protein, and higher fat can significantly reduce glucose and insulin and increase metabolically active ketone bodies. A ketogenic diet combined with triplet chemotherapy (gemcitabine, nab-paclitaxel, cisplatin) was shown to inhibit murine pancreatic KPC tumor growth and to triple the survival benefit of chemotherapy alone. The ketogenic diet combined with triple chemotherapy was associated with glucose depletion, altered TCA substrate usage, and NADH elevation.

Methods: In this Phase II randomized clinical trial (NCT04631445), we are evaluating a medically supervised ketogenic diet (MSKD) versus a standard diet when combined with the triplet therapy in patients with treatment-naive advanced pancreatic cancer. The primary endpoint is progression free survival for triplet therapy while on MSKD or non-MSKD. Secondary endpoints include disease control rate (PR+ CR+ SD for at least 9 weeks), change in CA 19-9 (or CA125, or CEA if not expressers of CA 19-9), average insulin levels, HbA1c, body weight, a comparison of gut microbial diversity, changes in serum metabolites and quality of life via the EORTC QLQ-C30 assessment. Unlike prior ketogenic intervention studies, the MSKD is being supported by a continuous care nutrition intervention through Virta Health Corp, that offers tracking of daily ketone and glucose levels, a web-based software application, education, and communication with a remote care team to ensure sustained nutritional ketosis. A total of 40 patients with untreated metastatic PDAC are planned for enrollment, 20 randomized to each arm. The trial opened for accrual November 2020.

Citation Format: Diana Hanna, Gayle S. Jameson, Drew W. Rasco, Angela Alistar, Richard C. Frank, Anthony B. El-Khoueiry, Julia E. Wiedmeier, Caroline Roberts, Brandon Fell, Sarah Hallberg, Denise Roe, Derek Cridebring, Joshua Rabinowitz, Stephen Thomas Gately, Daniel D. Von Hoff. Randomized Phase II trial of two different nutritional approaches for patients receiving treatment for their advanced pancreatic 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 CT549.

Mortality and glycemic control among patients with acute and chronic myeloid leukemia and diabetes: a case-control study

Aim

We examined the association between diabetes and survival in patients with acute and chronic myeloid leukemia and the association of leukemia with glycemic control.

Patients & methods

Patients with leukemia with and without diabetes (2007-2015) were retrospectively identified and matched 1:1 (n = 70 per group). Overall survival was estimated by the Kaplan-Meier method. Hemoglobin A_1c and glucose levels the year after leukemia diagnosis were compared by mixed models.

Results

Among 25 of 70 patients with diabetes, mean hemoglobin A_1c during the year after leukemia diagnosis was 6.8%. Kaplan-Meier-estimated 3-year survival was 46% for diabetes patients versus 45% for controls (p = 0.79).

Conclusion

No associations were found between leukemia, diabetes, survival and glycemic control.

Abstract 3015: IMiDs and BET inhibitors target distinct pathways of MYC dysregulation by super-enhancers in multiple myeloma

MYC dysregulation, the most common genetic aberration in multiple myeloma, is frequently due to the translocation of super-enhancers to the MYC locus. Several drugs target proteins that are enriched at many of these enhancers including BRD4 (BET inhibitors, BETi) and Ikaros (IMiDs), although their mechanism of action remains poorly understood. Here we present a characterization of the responses to these drugs in a collection of over sixty myeloma cell lines having a diversity of MYC rearrangements. We found that the anti-proliferative effects of these drugs significantly correlated with changes in MYC protein levels, consistent with both drugs targeting MYC expression. Despite this common target, there was no statistically significant correlation between the individual BETi and IMiD responses, suggesting that they act through different mechanisms. Of those lines having extremes of sensitivity or resistance, there were two major groups (BETiS/IMiDS and BETiS/IMiDR), a smaller group of four lines resistant to both drugs individually (BETiR/IMiDR) and only one line was BETiR/IMiDS. In the BETiR/IMiDR group, resistance to BETi was mediated by a BRD4-independent mechanism as BRD4 was efficiently released from the MYC-associated enhancers. In all three of BETiR/IMiDR cell lines that we examined, treatment with BETi and IMiD together abolished proliferation and down-regulated MYC, consistent with parallel BRD4- and Ikaros-dependent pathways driving MYC expression. These resistant lines all expressed high levels of the transcription factor ETV4 and knocking out its gene sensitized a line to each drug individually. Thus ETV4 appears to be necessary for the parallel pathways driving MYC expression. There were nine lines in the BETiS/IMiDR group. Sensitivity to BETi in these lines could be explained by either low ETV4 expression or by BETi repressing Ikaros levels (which was only observed in BETiS lines, suggesting that BRD4 drives IKZF1 expression in these lines). Thus, in ETV4-containing lines, BETi sensitivity is due to the simultaneously targeting of the BRD4- and Ikaros-dependent pathways. IMiD resistance likely was due to several reasons. In one cell line, OCIMY5, IMiD had little effect on Ikaros levels, likely due to the previously reported low levels of Cereblon. Seven of the eight remaining lines expressed high levels of either ETV4, or the other potential super-enhancer binding factors IRF4 or RUNX1. In the eight BETiS/IMiDS cell lines, IMiD strongly reduced both Ikaros and Aiolos protein levels, which likely caused IMiD sensitivity. As with the BETiS lines described above, the lines in this group either lacked ETV4 or BETi repressed Ikaros levels. In conclusion, by examining drug response in a collection of genetically annotated myeloma cell lines we have been able to identify factors that contribute the broad range of responses to BETi and IMiDs in myeloma cells.

Citation Format: Daniel L. Riggs, Camille Herzog, Victoria M. Garbitt, Niamh Keane, Courtney J. Hillukka, Zachary J. Hammond, Julia E. Wiedmeier, Seth J. Welsh, Shulan Tian, Huihuang Yan, Ranjan Maity, Nizar Bahlis, Paola Neri, W Michael Kuehl, Marta Chesi, P Leif Bergsagel. IMiDs and BET inhibitors target distinct pathways of MYC dysregulation by super-enhancers in multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3015.

Single-Cell Sequencing in Precision Medicine

The application of next-generation sequencing in cancer genomics allowed for a better understanding of the genetics and pathogenesis of cancer. Single-cell genomics is a relatively new field that has enhanced our current knowledge of the genetic diversity of cells involved in the complex biological systems of cancer. Single-cell genomics is a rapidly developing field, and current technologies can assay a single cell's gene expression, DNA variation, epigenetic state, and nuclear structure. Statistical and computational methods are central to single-cell genomics and allows for extraction of meaningful information. The translational application of single-cell sequencing in precision cancer therapy has the potential to improve cancer diagnostics, prognostics, targeted therapy, early detection, and noninvasive monitoring. Furthermore, single-cell genomics will transform cancer research as even initial experiments have revolutionized our current understanding of gene regulation and disease.

Intrauterine growth restriction perturbs nucleosome depletion at a growth hormone-responsive element in the mouse IGF-1 gene

Intrauterine growth restriction (IUGR) is a common human pregnancy complication. IUGR offspring carry significant postnatal risk for early-onset metabolic syndrome, which is associated with persistent reduction in IGF-1 protein expression. We have previously shown that preadolescent IUGR male mice have decreased hepatic IGF-1 mRNA and circulating IGF-1 protein at postnatal day 21, the age when growth hormone (GH) normally upregulates hepatic IGF-1 expression. Here we studied nucleosome occupancy and CpG methylation at a putative growth hormone-responsive element in intron 2 (in2GHRE) of the hepatic IGF-1 gene in normal, sham-operated, and IUGR mice. Nucleosome occupancy and CpG methylation were determined in embryonic stem cells (ESCs) and in liver at postnatal days 14, 21, and 42. For CpG methylation, additional time points out to 2 yr were analyzed. We confirmed the putative mouse in2GHRE was GH-responsive, and in normal mice, a single nucleosome was displaced from the hepatic in2GHRE by postnatal day 21, which exposed two STAT5b DNA binding sites. Nucleosome displacement correlated with developmentally programmed CpG demethylation. Finally, IUGR significantly altered the nucleosome-depleted region (NDR) at the in2GHRE of IGF-1 on postnatal day 21, with either complete absence of the NDR or with a shifted NDR exposing only one of two STAT5b DNA binding sites. An NDR shift was also seen in offspring of sham-operated mothers. We conclude that prenatal insult such as IUGR or anesthesia/surgery could perturb the proper formation of a well-positioned NDR at the mouse hepatic IGF-1 in2GHRE necessary for transitioning to an open chromatin state.

Early postnatal nutrition and programming of the preterm neonate

Early postnatal nutrition is a vital determinant of adult health; this is particularly true for the infant born prematurely and cared for in a hospital setting such as the neonatal intensive care unit. Human and animal studies support the contribution of postnatal dietary composition and the rate of extrauterine growth to long-term metabolic outcomes. One mechanism by which postnatal nutrition affects long-term outcome is via developmental programming. Programming, or the modulation of gene expression to impart a short-term advantage accompanied by a long-term cost, may be achieved by epigenetic modifications to chromatin. This review summarizes the details of postnatal nutritional content and rate of growth on the development of metabolic disease. The role of epigenetics in developmental programming of the preterm infant is also discussed, with an emphasis on animal models of dietary manipulation and directions in which the field must move in order to formulate effective feeding strategies for the preterm infant.