Topoisomerase IB (Top1) is a key eukaryotic nuclear enzyme that regulates the topology of DNA during replication and gene transcription. Anticancer drugs that block Top1 are either well-characterized interfacial poisons or lesser-known catalytic inhibitor compounds. Here we describe a new class of cytotoxic redox-stable cationic Au3+ macrocycles which, through hierarchical cluster analysis of cytotoxicity data for the lead compound, 3, were identified as either poisons or inhibitors of Top1. Two pivotal enzyme inhibition assays prove that the compounds are true catalytic inhibitors of Top1. Inhibition of human topoisomerase IIα (Top2α) by 3 was 2 orders of magnitude weaker than its inhibition of Top1, confirming that 3 is a type I-specific catalytic inhibitor. Importantly, Au3+ is essential for both DNA intercalation and enzyme inhibition. Macromolecular simulations show that 3 intercalates directly at the 5′-TA-3′ dinucleotide sequence targeted by Top1 via crucial electrostatic interactions, which include π–π stacking and an Au···O contact involving a thymine carbonyl group, resolving the ambiguity of conventional (drug binds protein) vs unconventional (drug binds substrate) catalytic inhibition of the enzyme. Surface plasmon resonance studies confirm the molecular mechanism of action elucidated by the simulations.

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The mechanisms underlying pathophysiological regulation of tissue macrophage (Mφ) subsets remain poorly understood. From the expression of 207 Mφ genes comprising 31 markers for 10 subsets, 45 transcription factors (TFs), 56 immunometabolism enzymes, 23 trained immunity (innate immune memory) enzymes, and 52 other genes in microarray data, we made the following findings. (1) When 34 inflammation diseases and tumor types were grouped into eight categories, there was differential expression of the 31 Mφ markers and 45 Mφ TFs, highlighted by 12 shared and 20 group-specific disease pathways. (2) Mφ in lung, liver, spleen, and intestine (LLSI-Mφ) express higher M1 Mφ markers than lean adipose tissue Mφ (ATMφ) physiologically. (3) Pro-adipogenic TFs C/EBPα and PPARγ and proinflammatory adipokine leptin upregulate the expression of M1 Mφ markers. (4) Among 10 immune checkpoint receptors (ICRs), LLSI-Mφ and bone marrow (BM) Mφ express higher levels of CD274 (PDL-1) than ATMφ, presumably to counteract the M1 dominant status via its reverse signaling behavior. (5) Among 24 intercellular communication exosome mediators, LLSI- and BM- Mφ prefer to use RAB27A and STX3 than RAB31 and YKT6, suggesting new inflammatory exosome mediators for propagating inflammation. (6) Mφ in peritoneal tissue and LLSI-Mφ upregulate higher levels of immunometabolism enzymes than does ATMφ. (7) Mφ from peritoneum and LLSI-Mφ upregulate more trained immunity enzyme genes than does ATMφ. Our results suggest that multiple new mechanisms including the cell surface, intracellular immunometabolism, trained immunity, and TFs may be responsible for disease group-specific and shared pathways. Our findings have provided novel insights on the pathophysiological regulation of tissue Mφ, the disease group-specific and shared pathways of Mφ, and novel therapeutic targets for cancers and inflammations.

Through retrospective review of consecutive charts, we compare the short-term and long-term clinical outcomes after robotic-assisted right colectomy with intracorporeal anastomosis (RIA) (n=89) and laparoscopic right colectomy with extracorporeal anastomosis (LEA) (n=135). Cohorts were similar in demographic characteristics, comorbidities, pathology, and perioperative outcomes (conversion, days to flatus and bowel movement, and length of hospitalization). The RIA cohort experienced statistically significant: less blood loss, shorter incision lengths, and longer specimen lengths than the LEA cohort. Operative times were significantly longer for the RIA group. No incisional hernias occurred in the RIA group, whereas the LEA group had 5 incisional hernias; mean follow-up was 33 and 30 months, respectively. RIA is effective and safe and provides some clinical advantages. Future studies may show that, in obese and other technically challenging patients, RIA facilitates resection of a longer, consistent specimen with less mesentery trauma that can be extracted through smaller incisions.

Ischemia reperfusion injury (IRI) during liver transplantation increases morbidity and contributes to allograft dysfunction. There are no therapeutic strategies to mitigate IRI. We examined a novel hypothesis: caspase 1 and caspase 11 serve as danger-associated molecular pattern (DAMPs) sensors in IRI. By performing microarray analysis and using caspase 1/caspase 11 double-knockout (Casp DKO) mice, we show that the canonical and non-canonical inflammasome regulators are upregulated in mouse liver IRI. Ischemic pre (IPC)- and post-conditioning (IPO) induce upregulation of the canonical and non-canonical inflammasome regulators. Trained immunity (TI) regulators are upregulated in IPC and IPO. Furthermore, caspase 1 is activated during liver IRI, and Casp DKO attenuates liver IRI. Casp DKO maintained normal liver histology via decreased DNA damage. Finally, the decreased TUNEL assay-detected DNA damage is the underlying histopathological and molecular mechanisms of attenuated liver pyroptosis and IRI. In summary, liver IRI induces the upregulation of canonical and non-canonical inflammasomes and TI enzyme pathways. Casp DKO attenuate liver IRI. Development of novel therapeutics targeting caspase 1/caspase 11 and TI may help mitigate injury secondary to IRI. Our findings have provided novel insights on the roles of caspase 1, caspase 11, and inflammasome in sensing IRI derived DAMPs and TI-promoted IRI-induced liver injury.

The structures, spectroscopy, and cytotoxicity of four novel nominally square-planar gold(III) chelates 1-4 with the general formula cis-AuCl2(X), where the ligand X is an anionic bidentate pyridyl- or isoquinolylamido chelating agent, are described. The Au-N(amido), Au-N(pyridyl), and Au-N(isoquinolyl) distances are 2.002(9)-2.016(3), 2.01(1)-2.037(3), and 2.037(3) Å, respectively. Density functional theory simulations afforded accurate gold(III) coordination geometries for 1-4 (bond distances and angles to within 5% of the X-ray values), while accurate transition energies were limited to those calculated in the UV spectral region. The complexes had variable stability in dimethyl sulfoxide: compound 3 (relatively rigid) was indefinitely stable, compounds 1 and 2 (conformationally flexible) slowly demetalated over 30 days, and 4 (extensively aromatic) formed an insoluble precipitate after 10 days (72 h in an aqueous buffer). The isoquinolylamido derivative 4 was sufficiently cytotoxic in the NCI-60 screen to undergo full five-dose testing. Notably low GI50 (1.8, 2.3, and 3.2 μM) and IC50 (4.0, 9.8, and 15 μM) values were recorded for the OVCAR-3, IGROV1, and SW-620 cell lines, respectively. Hierarchical cluster analysis employing the National Cancer Institute (NCI) data for known anticancer drugs and 4 revealed that compound 4 is mechanistically identical with the topoisomerase IIα (Top2) poison zorubicin and statistically similar to the topoisomerase IB (Top1) poisons camptothecin and 9-methoxycamptothecin. The Top2-catalyzed decatenation reaction of kinetoplast DNA was studied as a function of the concentration of 4: the compound acts as an interfacial poison of Top2 at low concentrations (<1 μM) and a catalytic inhibitor of the enzyme above 5 μM. Gel mobility shift assays (plasmid DNA substrate) showed that the catalytic inhibition of Top2 likely correlates with DNA binding by 4 at concentrations >5 μM. Compound 4 is also a catalytic inhibitor of Top1 at higher concentrations, consistent with DNA binding by the complex.

Background Current guidelines recommend laparoscopic cholecystectomy be offered for patients with acute cholecystitis except those deemed as high risk. Few studies have examined the impact of frailty on outcomes for patients undergoing laparoscopic cholecystectomy. Therefore, the aim of this study was to determine the association of frailty with postoperative morbidity and mortality in patients undergoing laparoscopic cholecystectomy for acute cholecystitis. Methods Patients undergoing laparoscopic cholecystectomy for acute cholecystectomy were identified from 2005 to 2010 in the American College of Surgeons National Surgical Quality Improvement Project (NSQIP). The Modified Frailty Index (mFI) was used a surrogate for frailty, and patients were stratified as non-frail (mFI 0), low frailty (mFI 1-2), intermediate frailty (mFI 3-4) and high frailty (mFI ≥ 5). Univariable and multivariable analyses were performed. Receiver operator curves (ROC) and an area under the curve (AUC) were generated to determine accuracy of mFI in predicting postoperative morbidity and mortality. Results Of the 6898 patients undergoing laparoscopic cholecystectomy, 3245 (47%) patients were non-frail. There were 2913 (42%) patients with low-frailty, 649 (9%) patients with intermediate frailty, and 91 (2%) with high frailty. Clavien IV complications were higher for intermediate frail patients (OR 1.81, 95% CI 1.00-3.28, p = 0.050) and high-frail patients (OR 4.59, 95% CI 1.98-10.7, p < 0.001). Additionally, mortality was higher for patients with intermediate frailty (OR 4.69, 95% CI 1.37-16.0, p = 0.014) and high frailty (OR 12.2, 95% CI 2.67-55.5, p = 0.001). The mFI had excellent accuracy for mortality (AUC = 0.83) and Clavien IV complications (AUC = 0.73). Conclusion Frailty is associated with postoperative morbidity and mortality in patients undergoing laparoscopic cholecystectomy for acute cholecystitis.

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