The C-Terminal Acidic Tail Modulates the Anticancer Properties of HMGB1.

Energy metabolism reprogramming was recently listed as a hallmark of cancer. In this process, the switch from pyruvate kinase isoenzyme type M1 to pyruvate kinase isoenzyme type M2 (PKM2) is believed to play a crucial role. Interestingly, the activity of the active form of PKM2 can efficiently be inhibited by the high-mobility group box 1 (HMGB1) protein, leading to a rapid blockage of glucose-dependent aerobic respiration and cancer cell death. HMGB1 is a member of the HMG protein family. It contains two DNA-binding HMG-box domains and an acidic C-terminal tail capable of positively or negatively modulating its biological properties. In this work, we report that the deletion of the C-terminal tail of HMGB1 increases its activity towards a large panel of cancer cells without affecting the viability of normal immortalized fibroblasts. Moreover, in silico analysis suggests that the truncated form of HMGB1 retains the capacity of the full-length protein to interact with PKM2. However, based on the capacity of the cells to circumvent oxidative phosphorylation inhibition, we were able to identify either a cytotoxic or cytostatic effect of the proteins. Together, our study provides new insights in the characterization of the anticancer activity of HMGB1.

Expression Pattern of Purinergic Signaling Components in Colorectal Cancer Cells and Differential Cellular Outcomes Induced by Extracellular ATP and Adenosine.

The purine nucleotide adenosine triphosphate (ATP) is known for its fundamental role in cellular bioenergetics. However, in the last decades, different works have described emerging functions for ATP, such as that of a danger signaling molecule acting in the extracellular space on both tumor and stromal compartments. Beside its role in immune cell signaling, several studies have shown that high concentrations of extracellular ATP can directly or indirectly act on cancer cells. Accordingly, it has been reported that purinergic receptors are widely expressed in tumor cells. However, their expression pattern is often associated with contradictory cellular outcomes. In this work, we first investigated gene expression profiles through "RNA-Sequencing" (RNA Seq) technology in four colorectal cancer (CRC) cell lines (HT29, LS513, LS174T, HCT116). Our results demonstrate that CRC cells mostly express the A2B, P2X4, P2Y1, P2Y2 and P2Y11 purinergic receptors. Among these, the P2Y1 and P2Y2 coding genes are markedly overexpressed in all CRC cells compared to the HCEC-1CT normal-like colonic cells. We then explored the cellular outcomes induced by extracellular ATP and adenosine. Our results show that in terms of cell death induction extracellular ATP is consistently more active than adenosine against CRC, while neither compound affected normal-like colonic cell survival. Intriguingly, while for the P2Y2 receptor pharmacological inhibition completely abolished the rise in cytoplasmic Ca2+ observed after ATP exposure in all CRC cell lines, Ca2+ mobilization only impacted the cellular outcome for HT29. In contrast, non-selective phosphodiesterase inhibition completely abolished the effects of extracellular ATP on CRC cells, suggesting that cAMP and/or cGMP levels might determine cellular outcome. Altogether, our study provides novel insights into the characterization of purinergic signaling in CRC.

Update of variants identified in the pancreatic ß-cell KATP channel genes KCNJ11 and ABCC8 in individuals with congenital hyperinsulinism and diabetes.

The most common genetic cause of neonatal diabetes and hyperinsulinism is pathogenic variants in ABCC8 and KCNJ11. These genes encode the subunits of the ß-cell ATP-sensitive potassium channel, a key component of the glucose-stimulated insulin secretion pathway. Mutations in the two genes cause dysregulated insulin secretion; inactivating mutations cause an oversecretion of insulin, leading to congenital hyperinsulinism, whereas activating mutations cause the opposing phenotype, diabetes. This review focuses on variants identified in ABCC8 and KCNJ11, the phenotypic spectrum and the treatment implications for individuals with pathogenic variants.

Secondary Metabolites from the Culture of the Marine-derived Fungus Paradendryphiella salina PC 362H and Evaluation of the Anticancer Activity of Its Metabolite Hyalodendrin.

High-throughput screening assays have been designed to identify compounds capable of inhibiting phenotypes involved in cancer aggressiveness. However, most studies used commercially available chemical libraries. This prompted us to explore natural products isolated from marine-derived fungi as a new source of molecules. In this study, we established a chemical library from 99 strains corresponding to 45 molecular operational taxonomic units and evaluated their anticancer activity against the MCF7 epithelial cancer cell line and its invasive stem cell-like MCF7-Sh-WISP2 counterpart. We identified the marine fungal Paradendryphiella salina PC 362H strain, isolated from the brown alga Pelvetia caniculata (PC), as one of the most promising fungi which produce active compounds. Further chemical and biological characterizations of the culture of the Paradendryphiella salina PC 362H strain identified (-)-hyalodendrin as the active secondary metabolite responsible for the cytotoxic activity of the crude extract. The antitumor activity of (-)-hyalodendrin was not only limited to the MCF7 cell lines, but also prominent on cancer cells with invasive phenotypes including colorectal cancer cells resistant to chemotherapy. Further investigations showed that treatment of MCF7-Sh-WISP2 cells with (-)-hyalodendrin induced changes in the phosphorylation status of p53 and altered expression of HSP60, HSP70 and PRAS40 proteins. Altogether, our study reveals that this uninvestigated marine fungal crude extract possesses a strong therapeutic potential against tumor cells with aggressive phenotypes and confirms that members of the epidithiodioxopiperazines are interesting fungal toxins with anticancer activities.

The role of cytokines in the regulation of NK cells in the tumor environment.

Natural killer (NK) cells are innate lymphoid cells that are important effectors in the first line of defense toward transformed cells. This is mediated both by direct cytotoxic mechanisms and by production of immunoregulatory cytokines. Recent evidence has shown that NK cells also display memory, similar to the cells of the adaptive immune system. Cytokines are pivotal for the maturation, activation and survival of NK cells. Interleukins (IL)-2, IL-12, IL-15, IL-18, IL-21 and type I interferons positively regulate NK cell function, either independently or in cooperation, whereas other cytokines, such as IL-23 and IL-27, may enhance or suppress NK cell function depending on the context. In the tumor microenvironment, TGFß, IL-10 and IL-6 suppress NK cell activity not only directly, but also indirectly, by affecting immunosuppressive cells and by antagonizing the effect of stimulatory cytokines, thereby dampening the antitumor response of NK cells and promoting subsequent tumor evasion and progression. Increased understanding of the NK cell response to cytokines has provided a better understanding of their impaired function in tumors which may aid in the development of novel immunotherapeutic strategies to enhance NK cell responses in cancer patients.

Prospective Assessment of Clinical Risk Factors and Biomarkers of Hypercoagulability for the Identification of Patients with Lung Adenocarcinoma at Risk for Cancer-Associated Thrombosis: The Observational ROADMAP-CAT Study.

BACKGROUND: The aim of this prospective study was to identify the most clinically relevant hypercoagulability biomarkers in lung adenocarcinoma patients for elaboration of an improved risk assessment model (RAM) for venous thromboembolism (VTE). SUBJECTS, MATERIALS, AND METHODS: One hundred fifty ambulatory patients with lung adenocarcinoma were prospectively enrolled. Thrombin generation, procoagulant phospholipid-dependent clotting time (Procoag-PPL), tissue factor activity (TFa), factor VIIa (FVIIa), factor V (FV), antithrombin, D-Dimers, P-selectin, and heparanase levels were assessed in platelet-poor plasma at inclusion (baseline) and at the end of the third chemotherapy cycle (third chemotherapy). Cox regression analysis was used to identify independent VTE predictors. RESULTS: At baseline, patients had significantly attenuated thrombin generation, shorter Procoag-PPL, higher levels of TFa, D-Dimers, and heparanase, and lower levels of FVIIa and P-selectin, compared with controls. A significant increase in Procoag-PPL, FV, and FVIIa and a decrease of P-selectin levels were observed between baseline and third chemotherapy. Hospitalization within the last 3 months prior to assessment, time since cancer diagnosis less than 6 months, mean rate index (MRI) of thrombin generation, and Procoag-PPL were independently associated with symptomatic VTE. Accordingly, a prediction model including Procoag-PPL and MRI showed significant discriminating capacity (area under the curve: 0.84). CONCLUSION: Ambulatory patients with lung adenocarcinoma may display pronounced blood hypercoagulability due to decreased Procoag-PPL, increased endothelial cell activation, and increased degradation of fibrin. Incorporation of Procoag-PPL and MRI of thrombin generation may improve the accuracy of a VTE-RAM in the above setting. IMPLICATIONS FOR PRACTICE: The prospective ROADMAP-CAT study identified two biomarkers of hypercoagulability, the procoagulant phospholipid-dependent clotting time (Procoag-PPL) and the mean rate index (MRI) of the propagation phase of thrombin generation assessed with the Calibrated Automated Thrombinoscope, as being clinically relevant for the classification of ambulatory patients with lung adenocarcinoma receiving a maximum of one cycle of chemotherapy into high and intermediate/low risk for venous thromboembolism. Measurement of Procoag-PPL and MRI within 1 month after the administration of the first chemotherapy cycle provides significant accuracy of the assessment. Association of the Procoag-PPL and MRI with the clinical risk assessment model for cancer-associated thrombosis in ambulatory patients with solid tumors (COMPASS-CAT RAM) further improved its accuracy.

A Predictive Score for Thrombosis Associated with Breast, Colorectal, Lung, or Ovarian Cancer: The Prospective COMPASS-Cancer-Associated Thrombosis Study.

BACKGROUND: The stratification of outpatients on chemotherapy for breast, colorectal, lung, and ovarian cancers at risk of venous thromboembolism (VTE) remains an unmet clinical need. The derivation of a risk assessment model (RAM) for VTE in these patients was the aim of the study "Prospective Comparison of Methods for thromboembolic risk assessment with clinical Perceptions and AwareneSS in real life patients-Cancer Associated Thrombosis" (COMPASS-CAT). PATIENTS AND METHODS: The derivation cohort consisted of 1,023 outpatients. Patients on low molecular weight heparin (LMWH) thromboprophylaxis were excluded. Documented symptomatic VTE was the endpoint of the study. RESULTS: Patients had breast (61%), colorectal (17%), lung (13%), or ovarian cancer (8.6%) at localized (30%) or advanced stage (70%). In 64% of patients, cancer was diagnosed within the last 6 months prior to inclusion. Most of them were on chemotherapy when assessed. Symptomatic VTE occurred in 8.5% of patients. The COMPASS-CAT RAM includes the following variables: (a) anthracycline or anti-hormonal therapy, (b) time since cancer diagnosis, (c) central venous catheter, (d) stage of cancer, (e) presence of cardiovascular risk factors, (f) recent hospitalization for acute medical illness, (g) personal history of VTE, and (h) platelet count. At 6 months, patients stratified at low/intermediate and high-risk groups had VTE rates of 1.7% and 13.3%, respectively. The area under the curve of receiver operating characteristics analysis was 0.85. The sensitivity and specificity of the RAM were 88% and 52%, respectively. The negative and positive predictive values of the RAM were 98% and 13%, respectively. CONCLUSION: The COMPASS-CAT RAM includes reliable and easily collected VTE risk predictors and, in contrast to the Khorana score, it is applicable after the initiation of anticancer treatment in patients with common solid tumors. Its robustness for stratification of patients at high and low/intermediate VTE risk needs to be externally validated. IMPLICATIONS FOR PRACTICE: The Prospective Comparison of Methods for thromboembolic risk assessment with clinical Perceptions and AwareneSS in real life patients-Cancer Associated Thrombosis (COMPASS-CAT) study provides a new risk assessment model (RAM) for venous thromboembolism (VTE) applicable in outpatients with breast, colorectal, lung or ovarian cancer. The COMPASS-CAT RAM is robust, applicable during chemotherapy and determines the need for VTE prévention by including reliable and easily collected VTE predictors associated with cancer status, its treatment as well as with patients' characteristics and comorbidities. An independent external validation of the RAM is indicated before its use in clinical practice.

Impact of blood hypercoagulability on in vitro fertilization outcomes: a prospective longitudinal observational study.

BACKGROUND: Blood coagulation plays a crucial role in the blastocyst implantation process and its alteration may be related to in vitro fertilization (IVF) failure. We conducted a prospective observational longitudinal study in women eligible for IVF to explore the association between alterations of coagulation with the IVF outcome and to identify the biomarkers of hypercoagulability which are related with this outcome. METHODS: Thirty-eight women eligible for IVF (IVF-group) and 30 healthy, age-matched women (control group) were included. In the IVF-group, blood was collected at baseline, 5-8 days after administration of gonadotropin-releasing hormone agonist (GnRH), before and two weeks after administration of human follicular stimulating hormone (FSH). Pregnancy was monitored by measurement of ßHCG performed 15 days after embryo transfer. Thrombin generation (TG), minimal tissue factor-triggered whole blood thromboelastometry (ROTEM®), procoagulant phospholipid clotting time (Procoag-PPL®), thrombomodulin (TMa), tissue factor activity (TFa), factor VIII (FVIII), factor von Willebrand (FvW), D-Dimers and fibrinogen were assessed at each time point. RESULTS: Positive IVF occurred in 15 women (40%). At baseline, the IVF-group showed significantly increased TG, TFa and TMa and significantly shorter Procoag-PPL versus the control group. After initiation of hormone treatment TG was significantly higher in the IVF-positive as compared to the IVF-negative group. At all studied points, the Procoag-PPL was significantly shorter and the levels of TFa were significantly higher in the IVF-negative group compared to the IVF-positive one. The D-Dimers were higher in the IVF negative as compared to IVF positive group. Multivariate analysis retained the Procoag-PPL and TG as predictors for the IVF outcome. CONCLUSIONS: Diagnosis of women with hypercoagulability and their stratification to risk of IVF failure using a model based on the Procoag-PPL and TG is a feasible strategy for the optimization of IVF efficiency that needs to be validated in prospective trials.

Antimicrobial Oligophenalenone Dimers from the Soil Fungus Talaromyces stipitatus.

New polyketide-derived oligophenalenone dimers, 9a-epi-bacillisporin E (1) and bacillisporins F-H (2-5), along with the known bacillisporin A (6), were isolated from the fungus Talaromyces stipitatus. Their structures and absolute configurations were determined on the basis of spectroscopic analyses, electronic circular dichroism, and GIAO NMR shift calculation followed by DP4 analysis. The antimicrobial activity of these compounds was evaluated against a panel of human pathogenic bacteria. Among them, bacillisporin H (5) exhibited antimicrobial activity together with modest cytotoxicity against HeLa cells.

Bevacizumab with or without erlotinib as maintenance therapy in patients with metastatic colorectal cancer (GERCOR DREAM; OPTIMOX3): a randomised, open-label, phase 3 trial.

BACKGROUND: The combination of an anti-VEGF or an anti-EGFR-targeted monoclonal antibody with chemotherapy has shown clinical activity in patients with metastatic colorectal cancer. However, combining both anti-VEGF and anti-EGFR antibodies with chemotherapy in first-line treatment resulted in adverse outcomes. We assessed whether the combination of erlotinib, an EGFR tyrosine kinase inhibitor, with bevacizumab could increase the efficacy of maintenance therapy in patients with unresectable metastatic colorectal cancer. METHODS: This randomised, open-label, phase 3 study was undertaken in 49 centres in France, Austria, and Canada. Eligible patients were aged 18-80 years with histologically confirmed, unresectable metastatic colorectal cancer, WHO performance status 0-2, had received no previous therapy for metastatic disease, and had adequate organ function. Patients without disease progression after bevacizumab-based induction therapy were randomly assigned (1:1) by a minimisation technique to bevacizumab (7·5 mg/kg every 3 weeks) or bevacizumab plus erlotinib (150 mg once daily) as maintenance therapy until progression. All patients were stratified by centre, baseline performance status, age, and number of metastatic sites. The primary endpoint was progression-free survival on maintenance therapy analysed by intention to treat. We report the final analysis. This trial is registered with ClinicalTrials.gov, number NCT00265824. FINDINGS: Between Jan 1, 2007, and Oct 13, 2011, 700 eligible patients were enrolled; following induction treatment, patients without disease progression were randomly assigned to bevacizumab (n=228) or bevacizumab plus erlotinib (n=224). At the final analysis, median follow-up was 51·0 months (IQR 36·0-60·0) in the bevacizumab group and 48·3 months (31·5-61·0) in the bevacizumab plus erlotinib group. In the primary analysis (after 231 progression-free survival events), median progression-free survival from randomisation was 5·1 months (95% CI 4·1-5·9) in the bevacizumab plus erlotinib group compared with 6·0 months (4·6-7·9) in the bevacizumab group (stratified hazard ratio [HR] 0·79 [95% CI 0·60-1·06]; p=0·11; unstratified HR 0·76 [0·59-0·99]; p=0·043). In the final analysis, median progression-free survival from randomisation was 5·4 months (95% CI 4·3-6·2) in the bevacizumab plus erlotinib group compared with 4·9 months (4·1-5·7) in the bevacizumab group (stratified HR 0·81 [95% CI 0·66-1·01], p=0·059; unstratified HR 0·78 [0·68-0·96], p=0·019). At the final analysis, median overall survival from maintenance was 24·9 months (95% CI 21·4-28·9) in the bevacizumab plus erlotinib group and 22·1 months (19·6-26·7) in the bevacizumab group (stratified HR 0·79 [95% CI 0·63-0·99], p=0·036; unstratified HR 0·79 [0·64-0·98], p=0·035). The most frequent grade 3-4 adverse events were skin rash (47 [21%] of 220 patients in the bevacizumab plus erlotinib group vs none of 224 patients in the bevacizumab alone group), diarrhoea (21 [10%] vs two [<1%]), and asthenia (12 [5%] vs two [<1%]). INTERPRETATION: Maintenance bevacizumab plus erlotinib might be a new non-chemotherapy-based maintenance option for the first-line treatment of patients with unresectable metastatic colorectal cancer after bevacizumab-based induction therapy. FUNDING: GERCOR and F Hoffmann-La Roche.

A retrospective multicenter analysis of elderly Hodgkin lymphoma: outcomes and prognostic factors in the modern era.

We investigated a recent (January 1999 to December 2009) cohort of 95 elderly Hodgkin lymphoma subjects. At diagnosis, median age was 67 years (range, 60-89 years), whereas 61% had significant comorbidity, 26% were unfit, 17% had a geriatric syndrome, and 13% had loss of activities of daily living. Overall response rate to therapy was 85%, whereas incidence of bleomycin lung toxicity was 32% (with associated mortality rate, 25%). With 66-month median follow-up, 2-year and 5-year overall survival were 73% and 58%, respectively (advanced-stage, 63% and 46%, respectively). Most International Prognostic Score factors were not prognostic on univariate analyses, whereas Cox multivariate regression identified 2 risk factors associated with inferior overall survival: (1) age more than 70 years (2.24; 95% CI, 1.16-4.33, P = .02) and (2) loss of activities of daily living (2.71; 95% CI, 1.07-6.84, P = .04). Furthermore, a novel survival model based on number of these risk factors (0, 1, or 2) showed differential 2-year OS of 83%, 70%, and 13%, respectively (P < .0001) and 5-year OS of 73%, 51%, and 0%, respectively (P < .0001).

Genotype-histotype-phenotype correlations in hyperinsulinemic hypoglycemia.

Hyperinsulinemic hypoglycemia (HH) of pancreatic origin includes congenital hyperinsulinism (CHI), insulinoma, insulinomatosis, and adult-onset non-insulinoma persistent hyperinsulinemic hypoglycemia syndrome (NI-PHHS). In this review, we describe the genotype-histotype-phenotype correlations in HH and their therapeutic implications. CHI can occur from birth or later on in life. Histologically, diffuse CHI shows diffuse beta cell hypertrophy with a few giant nuclei per islet of Langerhans, most frequently caused by loss-of-function mutations in ABCC8 or KCNJ11. Focal CHI is histologically characterized by focal adenomatous hyperplasia consisting of confluent hyperplastic islets, caused by a paternal ABCC8/KCNJ11 mutation combined with paternal uniparental disomy of 11p15. CHI in Beckwith-Wiedemann syndrome is caused by mosaic changes in the imprinting region 11p15.4-11p15.5, leading to segmental or diffuse overgrowth of endocrine tissue in the pancreas. Morphological mosaicism of pancreatic islets is characterized by occurence of hyperplastic (type 1) islets in one or a few lobules and small (type 2) islets in the entire pancreas. Other rare genetic causes of CHI show less characteristic or unspecific histology. HH with a predominant adult onset includes insulinomas, which are pancreatic insulin-producing endocrine neoplasms, in some cases with metastatic potential. Insulinomas occur sporadically or as part of multiple endocrine neoplasia type 1 due to MEN1 mutations. MAFA mutations may histologically lead to insulinomatosis with insulin-producing neuroendocrine microadenomas or neuroendocrine neoplasms. NI-PHHS is mainly seen in adults and shows slight histological changes in some patients, which have been defined as major and minor criteria. The genetic cause is unknown in most cases. The diagnosis of HH, as defined by genetic, histological, and phenotypic features, has important implications for patient management and outcome.

A phase I/II trial of bortezomib combined concurrently with gemcitabine for relapsed or refractory DLBCL and peripheral T-cell lymphomas.

There remains an unmet therapeutic need for patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) and peripheral T-cell lymphoma (PTCL). We conducted a phase I/II trial with bortezomib (dose-escalated to 1·6 mg/m(2) ) given concurrently with gemcitabine (800 mg/m(2) ) days 1 + 8 q21 d. Of 32 patients, 16 each had relapsed/refractory PTCL and DLBCL. Median prior therapies were 3 and 35% had failed transplant. Among the first 18 patients, 67% experienced grade 3/4 neutropenia and/or grade 3/4 thrombocytopenia resulting in repeated treatment delays (relative dose intensity: 46%). Thus, the study was amended to give bortezomib and gemcitabine days 1 + 15 q28 d, which resulted in markedly improved tolerability. Among all patients, the overall response rate (ORR) was 24% with 19% complete remission (CR; intent-to-treat (ITT) ORR 16%, CR 13%), which met criteria for futility. The ORR for DLBCL was 10% (CR 10%) vs. 36% for PTCL (CR 27%). Among 6 PTCL patients treated on the modified schedule, ORR by ITT was 50% (CR 30%). Altogether, concurrent bortezomib/gemcitabine given days 1 + 8 q21 d was not tolerable, while modification to a bi-monthly schedule allowed consistent treatment delivery. Whereas efficacy of this combination was low in heavily pre-treated DLBCL, there was a signal of activity in relapsed/refractory PTCL utilizing the modified schedule.

DNA alkylation damage and autophagy induction.

Many alkylating agents are used as chemotherapeutic drugs and have a long history of clinical application. These agents inflict a wide range of DNA damage resulting in a complex cellular response. After DNA damage, cells trigger a series of signaling cascades promoting cellular survival and cell cycle blockage which enables time for DNA repair to occur. More recently, induction of autophagy has been observed in cancer cells after treatment with different DNA-targeted anticancer drugs, including alkylating agents. Several studies have demonstrated that induction of autophagy after DNA damage delays apoptotic cell death and may therefore lead to chemoresistance, which is the limiting factor for successful chemotherapy. On the other hand, depending on the extent of damage and the cellular context, the induction of autophagy may also contribute to cell death. Given these conflicting results, many studies have been conducted to better define the role of autophagy in cancer cells in response to chemotherapy. In this review, we describe the main alkylating agents used in clinical oncology as well as the cellular response they evoke with emphasis on autophagy.

An explorative study of nurses' perception of turnover and retention.

INTRODUCTION: High nurse turnover at hospitals is a major societal problem. Knowledge of how to decrease the turnover rate is important. The aim of this study was to explore nurses' perception of nurse turnover and retention. METHODS: An explorative study was designed with table-top simulations involving newly graduated nurses, experienced nurses and nurse supervisors in internal medicine departments. The simulations were audio-recorded and transcribed. The participants took notes, which were transcribed. The citations were sorted into subthemes and themes by use of inductive content analysis. RESULTS: Fifteen workshops involving a total of 43 nurses were conducted. Four overarching themes were identified: core clinical competence, professionalism, organisation and culture. The new nurses focused on development and evaluation of core clinical competences to be able to provide safe patient care. The experienced nurses favoured influence on own work and a plan for continuous professional development. The importance of a good learning culture and of collegial and social factors was mentioned by both groups of nurses. CONCLUSIONS: The table-top simulations with newly graduated nurses, senior nurses and nurses responsible for education provided valuable insights into the nurses´ perspectives of determinants of nurse turnover and retention in internal medicine wards. FUNDING: None. TRIAL REGISTRATION: Not relevant.

PARPs and the DNA damage response.

Adenosine diphosphate (ADP)-ribosylation is an important posttranslational modification catalyzed by a variety of enzymes, including poly (ADP ribose) polymerases (PARPs), which use nicotinamide adenine dinucleotide (NAD(+)) as a substrate to synthesize and transfer ADP-ribose units to acceptor proteins. The PARP family members possess a variety of structural domains, span a wide range of functions and localize to various cellular compartments. Among the molecular actions attributed to PARPs, their role in the DNA damage response (DDR) has been widely documented. In particular, PARPs 1-3 are involved in several cellular processes that respond to DNA lesions, which include DNA damage recognition, signaling and repair as well as local transcriptional blockage, chromatin remodeling and cell death induction. However, how these enzymes are able to participate in such numerous and diverse mechanisms in response to DNA damage is not fully understood. Herein, the DDR functions of PARPs 1-3 and the emerging roles of poly (ADP ribose) polymers in DNA damage are reviewed. The development of PARP inhibitors, their applications and mechanisms of action are also discussed in the context of the DDR.

In vivo topoisomerase I inhibition attenuates the expression of hypoxia-inducible factor 1α target genes and decreases tumor angiogenesis.

Topoisomerase I is a privileged target for widely used anticancer agents such as irinotecan. Although these drugs are classically considered to be DNA-damaging agents, increasing evidence suggests that they might also influence the tumor environment. This study evaluates in vivo cellular and molecular modifications induced by irinotecan, a topoisomerase I-directed agent, in patient-derived colon tumors subcutaneously implanted in athymic nude mice. Irinotecan was given intraperitoneally at 40 mg/kg five times every 5 d, and expression profiles were evaluated at d 25 in tumors from treated and untreated animals. Unexpectedly, the in vivo antitumor activity of irinotecan was closely linked to a downregulation of hypoxia-inducible factor-1α (HIF1A) target genes along with an inhibition of HIF1A protein accumulation. The consequence was a decrease in tumor angiogenesis leading to tumor size stabilization. These results highlight the molecular basis for the antitumor activity of a widely used anticancer agent, and the method used opens the way for mechanistic studies of the in vivo activity of other anticancer therapies.

Analysis of very elderly (≥80 years) non-hodgkin lymphoma: impact of functional status and co-morbidities on outcome.

Data on outcome, prognostic factors, and treatment for very elderly non-Hodgkin lymphomas (NHL) is sparse. We conducted a multicentre retrospective analysis of NHL patients ≥80 years (at diagnosis) treated between 1999 and 2009. Detailed characteristics were obtained including geriatric syndromes, activities of daily living (ADLs), and co-morbidities using the Cumulative Illness Rating Scale-Geriatrics (CIRS-G). We identified 303 patients: 170 aggressive NHL (84% B cell/16% T cell) and 133 indolent NHL (82% B cell/18% T cell). Median age was 84 years (80-95). A geriatric syndrome was present in 26% of patients, 18% had ≥1 grade 4 CIRS-G, and 14% had loss of ADLs. At 49-month median follow-up, 4-year progression-free (PFS) and overall survival (OS) for aggressive NHLs were 31% and 44% respectively (stage I/II: PFS 53% and OS 66%; stage III/IV: PFS 20% and OS 32%; P < 0·0001 and 0·0002, respectively). Four-year PFS and OS for indolent NHL were 44% and 66% respectively, regardless of stage. Multivariate regression analysis identified two key factors that predicted inferior PFS and OS for both NHL groups: lack of CR and loss of ADLs. Prospective studies for very elderly NHL that incorporate geriatric tools, especially ADLs, are warranted.

Large molecular size EDTA-resistant complexes containing S100A12, ERAC, in serum during inflammatory conditions.

The pro-inflammatory, leukocyte-derived S100A12 protein occurs as calcium-dependent oligomers in serum, while EDTA plasma from the majority of healthy individuals contains only monomers. Addition of 5 mM EDTA to serum leads to a rapid dissociation of the oligomers in most samples. However, using gel permeation chromatography, we have found that sera from some patients and seemingly healthy individuals contain molecular complexes in the 400-1000 kDa range reacting with anti-S100A12 even in the presence of EDTA; for these we introduce the name ERAC (EDTA Resistant S100A12 Complexes). Based upon monoclonal antibodies and the lateral flow principle, we have developed a quantitative rapid ERAC test giving results within 10 minutes. The highest prevalence of ERAC positivity was found in sera from patients with concomitant rheumatoid arthritis and coronary heart disease. The structure of ERAC is not yet known. Further studies are needed to analyse the mechanism behind the appearance of ERAC and the possible association with inflammatory-related diseases.

Ataxia telangiectasia mutated- and Rad3-related kinase drives both the early and the late DNA-damage response to the monofunctional antitumour alkylator S23906.

Numerous anticancer agents and environmental mutagens target DNA. Although all such compounds interfere with the progression of the replication fork and inhibit DNA synthesis, there are marked differences in the DNA-damage response pathways they trigger, and the relative impact of the proximal or the distal signal transducers on cell survival is mainly lesion-specific. Accordingly, checkpoint kinase inhibitors in current clinical development show synergistic activity with some DNA-targeting agents, but not with others. In the present study, we characterize the DNA-damage response to the antitumour acronycine derivative S23906, which forms monofunctional adducts with guanine residues in the minor groove of DNA. S23906 exposure is accompanied by specific recruitment of RPA (replication protein A) at replication sites and rapid Chk1 activation. In contrast, neither MRN (Mre11-Rad50-Nbs1) nor ATM (ataxia-telangiectasia mutated), contributes to the initial response to S23906. Interestingly, genetic attenuation of ATR (ATM- and Ras3-related) activity inhibits not only the early phosphorylation of histone H2AX and Chk1, but also interferes with the late phosphorylation of Chk2. Moreover, loss of ATR function or pharmacological inhibition of the checkpoint kinases by AZD7762 is accompanied by abrogation of the S-phase arrest and increased sensitivity towards S23906. These findings identify ATR as a central co-ordinator of the DNA-damage response to S23906, and provide a mechanistic rationale for combinations of S23906 and similar agents with checkpoint abrogators.