Citations

Abstract The nuclear hormone receptor peroxisome proliferator-activated receptor delta (PPARδ) is a ligand-dependent transcription factor involved in fatty acid metabolism, obesity, wound healing, inflammation, and cancer. Although PPARδ has been shown to promote intestinal adenoma formation and growth, the molecular mechanisms underlying the contribution of PPARδ to colorectal cancer remain unclear. Here, we demonstrate that activation of PPARδ induces expansion of colonic cancer stem cells (CSC) and promotes colorectal cancer liver metastasis by binding to the Nanog promoter and enhancing Nanog expression. Moreover, PPARδ mediated the effect of a high-fat diet in promoting liver metastasis and induction of colonic CSC expansion. Our findings uncover a novel role of dietary fats in colorectal cancer metastasis and reveal novel mechanisms underlying PPARδ-mediated induction of CSCs and those responsible for the contribution of dietary fats to colorectal cancer progression. These findings may provide a rationale for developing PPARδ antagonists to therapeutically target CSCs in colorectal cancer. Significance: These findings show that PPARδ contributes to colorectal cancer metastasis by expanding the CSC population, indicating that antagonists that target PPARδ may be beneficial in treating colorectal cancer.

Background. Kidneys from deceased donors with acute kidney injury (AKI) are more likely to be discarded because of concerns for poor outcomes after transplantation. The aim of this study was to determine the long-term outcomes of a large cohort of patients transplanted utilizing kidneys from deceased donors with AKI. Methods. All patients receiving a deceased donor kidney transplant during a recent 10-year period were included. Acute Kidney Injury Network (AKIN) criteria were used to classify the donors. Donor kidneys with >10% cortical necrosis or more than mild chronic changes were discarded. The primary outcome is the combined endpoint of death or graft loss. Results. The cohort included 1313 kidneys from 974 donors, AKIN stage 0 (no AKI) in 319 (24.3%), stage 1 in 370 (28.2%), stage 2 in 177 (13.5), and stage 3 in 447 (34.0%). Estimated 5-year graft survival (95% confidence interval) was 78.5% (72.5-84.5), 77.8% (72.8-82.1), 83.8% (76.8-88.9), and 84.6% (79.5-88.7) for AKIN donor stage 0 to 3, respectively (log-rank P = 0.10). After adjusting for baseline differences, the hazard ratio (95% confidence interval) for the combined endpoint for the AKIN stage 3 group (relative to AKIN 0 group) was 0.70 (0.45-1.10). Delayed graft function occurred in 44.6% and 75.4% of AKIN 2 and 3 groups, as compared to 33.9% and 33.5% in AKIN 0 and 1 ( P < 0.001). Conclusion. We conclude that transplanting selected kidneys from deceased donors with AKI with preimplantation biopsy showing <10% cortical necrosis and no more than mild chronic changes have excellent long-term graft survival.

5031 Background: The phase 2 TRITON2 study (NCT02952534) is evaluating the PARP inhibitor rucaparib in patients with mCRPC who have a deleterious germline or somatic alteration in BRCA ( BRCA1 or BRCA2) or 1 of 13 other DNA damage repair genes. Here we present analyses of tumor genomics and baseline clinical characteristics in mCRPC patients with a deleterious alteration in BRCA. Methods: Plasma (baseline) and tissue (archival or baseline) samples from patients with a deleterious alteration in BRCA were analyzed using Foundation Medicine next-generation sequencing assays. The alterations and zygosity of the alterations that were detected, as well as the somatic/germline status from Color Genomics testing, were summarized. Associations between genomic alterations, DNA yield, allele frequency, and baseline clinical characteristics were investigated. Results: Results are shown in the Table for a cohort of 40 BRCA2 and 5 BRCA1 patients enrolled in TRITON2 (Abida W et al. Presented at ESMO 2018. Abst 793PD). A biallelic alteration was observed in 21 of the 22 BRCA2 patients (95%) for whom alteration zygosity could be determined. Among the 5 BRCA1 patients, 1 alteration was monoallelic and 4 were of unknown zygosity. Co-occurring alterations in cancer-related or DNA damage repair genes were observed in many patients with BRCA alterations. At baseline, cell-free DNA (cfDNA) yield correlated positively with the sum of target lesions (STL; P= 0.04), but not with prostate-specific antigen (PSA) levels ( P= 0.86). No correlation was observed between allele frequency of the BRCA alteration baseline STL ( P= 0.68) or PSA levels ( P= 0.97). Conclusions: Patients with a BRCA mutation enrolled in TRITON2 demonstrate a profile of genomic alterations consistent with that of prior studies of patients with mCRPC. Plasma cfDNA profiling showed a correlation between baseline cfDNA yield and measurable tumor burden, but not baseline PSA. Clinical trial information: NCT02952534. [Table: see text]

TPS2656 Background: ESCC remains the predominant histological subtype of, and accounts for most deaths from, esophageal cancer. PD-1 inhibition has demonstrated antitumor activity and was generally well tolerated in patients (pts) with advanced unresectable or metastatic ESCC. Tislelizumab, an investigational anti-PD-1 antibody, was engineered to minimize binding to FcγR on macrophages to abrogate antibody-dependent phagocytosis, a mechanism of T-cell clearance and potential resistance to anti-PD-1 therapy. Results from early phase clinical studies suggest single-agent tislelizumab was generally well tolerated and had antitumor activity in pts with solid tumors, including ESCC. Methods: This phase 3, randomized, placebo-controlled, double-blind study (NCT03783442) is designed to evaluate the efficacy and safety of tislelizumab plus chemotherapy as first-line treatment of unresectable, locally advanced recurrent or metastatic ESCC. Adult pts with histologically confirmed ESCC that had metastatic disease either at first diagnosis or with a ≥6 month treatment-free interval will be eligible. Additional eligibility criteria include measurable/evaluable disease, ECOG performance score ≤1, and no prior anti-PD-(L)-1, PD-L2, or other first-line therapy or palliative radiation treatment ≤4 weeks before treatment. Approximately 480 pts will be randomized 1:1 to receive investigator-chosen chemotherapy (ICC) plus tislelizumab 200 mg IV Q3W or ICC plus placebo. Chemotherapy options include: platinum (cisplatin 60–80 mg/m2 or oxaliplatin 130 mg/m2 IV Q3W) plus 5-FU 750–800 mg/m2 IV daily for 5 days Q3W; or platinum plus capecitabine 1000 mg/m2 orally BID for 14 days Q3W; or platinum + paclitaxel 175 mg/m2 IV Q3W. Progression-free survival and overall survival are coprimary endpoints; secondary endpoints include objective response rate, duration of response, and health-related quality-of-life. Safety will be assessed by monitoring adverse events, physical examinations, vital signs, and electrocardiograms. This study is actively enrolling. Clinical trial information: NCT03783442.

AbstractPatients with phosphoglucomutase (PGM1) deficiency, a congenital disorder of glycosylation (CDG) suffer from multiple disease phenotypes. Midline cleft defects are present at birth. Overtime, additional clinical phenotypes, which include severe hypoglycemia, hepatopathy, growth retardation, hormonal deficiencies, hemostatic anomalies, frequently lethal, early‐onset of dilated cardiomyopathy and myopathy emerge, reflecting the central roles of the enzyme in (glycogen) metabolism and glycosylation. To delineate the pathophysiology of the tissue‐specific disease phenotypes, we constructed a constitutive Pgm2 (mouse ortholog of human PGM1)‐knockout (KO) mouse model using CRISPR‐Cas9 technology. After multiple crosses between heterozygous parents, we were unable to identify homozygous life births in 78 newborn pups (P = 1.59897E‐06), suggesting an embryonic lethality phenotype in the homozygotes. Ultrasound studies of the course of pregnancy confirmed Pgm2‐deficient pups succumb before E9.5. Oral galactose supplementation (9 mg/mL drinking water) did not rescue the lethality. Biochemical studies of tissues and skin fibroblasts harvested from heterozygous animals confirmed reduced Pgm2 enzyme activity and abundance, but no change in glycogen content. However, glycomics analyses in serum revealed an abnormal glycosylation pattern in the Pgm2+/− animals, similar to that seen in PGM1‐CDG.