Survival In Presence Research Articles

The Use of Campenot Trichambers for the Study of Peripheral Neuronal Growth and Survival in Presence of Thrombotic Factors and Serpins.

The mechanisms underlying nervous system injury, such as spinal cord injury (SCI), traumatic brain injury (TBI), and peripheral nerve injury are complex and not well understood. Following acute tissue damage and cell death, inflammatory processes cause ongoing damage. Many factors regulate this inflammation, including factors that modulate chemokine expression. Serine proteases, including those of the thrombotic and thrombolytic pathways (e.g., thrombin, tPA, uPA) are upregulated during nervous system damage and can modulate the release and bioavailability of many chemokines. Virus-derived immunomodulators, such as Serp-1, a serine protease inhibitor (serpin), have protective effects by reducing inflammation and tissue damage. However, the precise mechanisms of Serp-1 neuroprotection are still being studied. Compartmentalized in vitro neuron culture systems, such as the Campenot trichamber, are useful for such mechanistic studies. This chapter provides a protocol for assembling and culturing rodent embryonic superior cervical ganglion (SCG) and dorsal root ganglion (DRG) neurons in Campenot trichambers, as well as instructive examples of the types of experiments enabled by these methods.

Retroperitoneal Lymph Node Metastasis in Gallbladder Cancer: As Bad as Distant Metastasis.

Ashish SinghBackground Regarding gallbladder cancer (GBC) there is conflicting evidence in the literature whether retroperitoneal lymph nodal metastases (RLNM) should be considered as regional nodal metastasis or as distant metastasis (DM) and the jury is out on radical curative surgery in presence of RLNM. This is an analysis of GBC patients, to see the effect of RLNM on survival and to compare with that of patients with DMs. Methods A retrospective analysis of a prospective database of patients of GBC with RLNM (interaortocaval and paraaortic) or DM on frozen section biopsy at surgery, between January 2013 and December 2018. Data was analyzed using the Statistical Package for the Social Sciences software (version 22.0). Survival in these two groups (RLNM and DM) was compared with log-rank test. A p -value of < 0.05 was considered significant. Results A total of 235 patients with ostensibly resectable GBC underwent surgical exploration. The planned curative resection was abandoned in 91 (39%) patients because of RLNM ( n = 20, 9%) or DM ( n = 71, 30%) on frozen section biopsy. Demographic profile and blood parameters were similar. The median survival for RLNM and DM groups were 5 (range 2-26) and 6 (range 2-24) months, respectively, with no significant difference on log-rank test ( p = 0.64). There was no 3-year or longer survivor in either group. Conclusion Due to similar poor survival in presence of RLNM or DM, RLNM should be considered as the equivalent of DM. This study strengthens evidence to avoid curative surgery in patients with RLNM. These lymph nodes should be sampled preoperatively, if suspicious on imaging, for fine-needle aspiration cytology and at surgery, as a routine for frozen section histological examination before initiating curative resection to avert a futile exercise.

Which test for crossing survival curves? A user\u2019s guideline

BackgroundThe exchange of knowledge between statisticians developing new methodology and clinicians, reviewers or authors applying them is fundamental. This is specifically true for clinical trials with time-to-event endpoints. Thereby, one of the most commonly arising questions is that of equal survival distributions in two-armed trial. The log-rank test is still the gold-standard to infer this question. However, in case of non-proportional hazards, its power can become poor and multiple extensions have been developed to overcome this issue. We aim to facilitate the choice of a test for the detection of survival differences in the case of crossing hazards.MethodsWe restricted the review to the most recent two-armed clinical oncology trials with crossing survival curves. Each data set was reconstructed using a state-of-the-art reconstruction algorithm. To ensure reproduction quality, only publications with published number at risk at multiple time points, sufficient printing quality and a non-informative censoring pattern were included. This article depicts the p-values of the log-rank and Peto-Peto test as references and compares them with nine different tests developed for detection of survival differences in the presence of non-proportional or crossing hazards.ResultsWe reviewed 1400 recent phase III clinical oncology trials and selected fifteen studies that met our eligibility criteria for data reconstruction. After including further three individual patient data sets, for nine out of eighteen studies significant differences in survival were found using the investigated tests. An important point that reviewers should pay attention to is that 28% of the studies with published survival curves did not report the number at risk. This makes reconstruction and plausibility checks almost impossible.ConclusionsThe evaluation shows that inference methods constructed to detect differences in survival in presence of non-proportional hazards are beneficial and help to provide guidance in choosing a sensible alternative to the standard log-rank test.

A new cure model accounting for extra non-cancer mortality: Validation and application to real data

The proportion of cancer patients cured of the disease is estimated with standard cure models assuming they have the same risk of death as the general population [1] . These patients, however often maintain an extra risk of dying compared to the overall population, which we assume is due to other causes than cancer [2] . The aim of the work was to develop and validate an extended cure model incorporating the estimated patients’ relative risk of death from other causes (α) compared to that observed in the general population. We extended the mixture cure model considering Weibull relative survival of the uncured by including a relative risk αwhich muliptlies the mortality observed in the general population. The parameters were estimated using maximum likelihood method for individual data and unweighted least square for grouped data. The extended model was evaluated through a simulation study of the performance and robustness. The validity of parameters estimated by both the standard and the extended cure models was evaluated on a set of simulations based on scenarios mirroring the behavior of lung and breast cancer from real data with 1000 samples of different sizes (500–20,000 cases each), with different values of α, with different length of follow-up, with set-ups where all the assumptions are verified or where some of them are not verified (survival of uncured patients does not follow a Weibull distribution; extra non-cancer death risk is dependent of age at diagnosis or randomly varies across patients). The models were also applied to real data: colon cancer data from the FRANCIM common database. When the assumptions were satisfied, the extended cure models correctly estimated the parameters and their standard errors, providing excellent coverage, in all scenario. The standard model underestimated the proportion of cured by 7% when α = 1.2, and by 40% when α = 2.0. Age effect on the proportion of cured was heavily overestimated. Among the extended models, the maximum likelihood estimation on individual data outperformed the unweighted least square for grouped data. When some of the assumptions were violated, parameter estimates by both extended models appeared fairly robust. Applied to real colon cancer data (e.g. in men), the extended models estimated close values of α respectively 1.28 (95% confidence interval [1.16–1.40] for grouped data and 1.23 [1.12–1.35] for individual data) and cure fraction (respectively 57.2% [54.3–60.1%] and 55.7%[53.3–58.1%]), higher than that of the conventional model (51.0% [48.5–53.5%] for grouped data and 51.6% [50.0–53.3%] for individual data). In individual data analyses, AIC was smaller for the extended model (55748) than for the conventional model (55760). The present analysis suggests that conventional indicators overestimate cancer-specific death and underestimate cure fraction for cancer survivors. The extended models are more efficient to estimate net survival in presence of an extra risk of dying.

Multiple cellular responses guarantee yeast survival in presence of the cell membrane/wall interfering agent sodium dodecyl sulfate

Sodium dodecyl sulfate (SDS), a representative anionic surfactant, is a commonly used reagent in studies of the cell membrane and cell wall. However, the mechanisms through which SDS affects cellular functions have not yet been fully examined. Thus, to gain further insights into the cellular functions and responses to SDS, we tested a haploid library of Saccharomyces cerevisiae single-gene deletion mutants to identify genes required for tolerance to SDS. After two rounds of screening, we found 730 sensitive and 77 resistant mutants. Among the sensitive mutants, mitochondrial gene expression; the mitogen-activated protein kinase signaling pathway; the metabolic pathways involved in glycoprotein, lipid, purine metabolic process, oxidative phosphorylation, cellular amino acid biosynthesis and pentose phosphate pathway were found to be enriched. Additionally, we identified a set of transcription factors related to SDS responses. Among the resistant mutants, disruption of ribosome biogenesis and translation alleviated SDS-induced cytotoxicity. Collectively, our results provided new insights into the mechanisms through which SDS regulates the cell membrane or cell wall.

Enhancement of glyphosate tolerance in rice (Oryza sativa L.) through mutation induction in EPSPS (5-enolpyruvylshikimate-3-phosphate synthase)

Generation of an herbicide-tolerant cultivar could be an important goal in rice breeding program. Therefore, a direct mutagenesis approach (megaprimer technique) was employed to generate the EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) mutant version called epsps in which glycine 96 was replaced by alanine. Then both EPSPS and epsps genes were separately cloned into pET22b system following transformation of E. coli BL21. The transformed bacteria showed a higher expression level of EPSPS and epsps extending their survival in presence of high levels of glyphosate. Interestingly, the bacteria harboring pET22b:epsps could grow in the medium containing 18 mM glyphosate. Subsequently, Hashemi rice cultivar was used to generate two types of transgenic rice including plants harboring either EPSPS (35S:EPSPS) or epsps (35S:epsps). Molecular analysis was performed on T3 putative transgenic plants so as to confirm the presence and expression of transgenes. The results demonstrated that 35S:epsps is actively and stably transcribed in T3 transgenic plants and developed a considerable tolerance towards glyphosate in comparison with the 35S:EPSPS plants. When compared to non-transgenic plants, the epsps mutant plants accumulated higher levels of chlorophyll and carotenoid in association with less shikimic acid, which are considered as some indicators of glyphosate side effects. Moreover, flavonoid accumulation was accompanied by enhanced levels of alkaloids and lower levels of proline in 35S:epsps plants; indicating that shikimic acid pathway is well functioning and transgenic plants especially 35S:epsps experienced less stress. Therefore, for the first time, rice was successfully transformed by 35S:epsps resulting in generation of transgenic plants with a considerable level of glyphosate tolerance.

Trichoderma harzianum formulations based on a biopolymeric hydrogel, znso4 and their combination

Novel wet and dry formulations of Trichoderma harzianum are reported. These were prepared by entrapment of spores and/or mycelia into the swollen matrices of hydrogel, or by physical mixing with xerogel containing zinc sulphate (ZnSO4). T. harzianum exhibited significantly high survival in presence of pure ZnSO4 up to a concentration of 150 ppm, beyond which gradual decline in viability occurred. Both the wet and dry compositions exhibited excellent shelf life, with the viability of T. harzianum up to180 d without any sign of toxicity due to the hydrogel carrier per se or with the impregnated ZnSO4. The combination of T. harzianum + ZnSO4 exhibited higher bio-activity than T. Harzianum or ZnSO4 alone against the soil borne fungal pathogen Rhizoctonia solani.

Ecotoxicological benthic impacts of experimental oil-contaminated marine snow deposition

Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) can pose serious threats to the marine benthic ecosystem as it results in a deposition of oil contaminated marine snow on the sediment surface. In a microcosm experiment we investigated the effects of oil in combination with artificial marine snow or kaolin clay on two benthic invertebrate species and benthic meiofauna. The amphipod showed a dose-dependent decrease in survival for both oil-contaminated clay and oil-contaminated marine snow. The gastropod was only affected by the highest concentration of oil-contaminated marine snow and had internal concentrations of PAHs with a similar distribution as oil-contaminated marine snow. Benthic copepods showed higher survival in presence of marine snow. This study revealed that marine snow on the sediment after oil spills affects organisms in a trait-dependent way and that it can be a vector for introducing oil into the food web.

Potentiation of paclitaxel effect by resveratrol in human breast cancer cells by counteracting the 17β-estradiol/estrogen receptor α/neuroglobin pathway.

Neuroglobin (NGB), an antiapoptotic protein upregulated by 17β-estradiol (E2), is part of E2/estrogen receptor α (ERα) pathway pointed to preserve cancer cell survival in presence of microenvironmental stressors including chemotherapeutic drugs. Here, the possibility that resveratrol (Res), an anticancer plant polyphenol, could increase the susceptibility of breast cancer cells to paclitaxel (Pacl) by affecting E2/ERα/NGB pathway has been evaluated. In MCF-7 and T47D (ERα-positive), but not in MDA-MB 231 (ERα-negative) nor in SK-N-BE (ERα and ERβ positive), Res decreases NGB levels interfering with E2/ERα-induced NGB upregulation and with E2-induced ERα and protein kinase B phosphorylation. Although Res treatment does not reduce cell viability by itself, this compound potentiates Pacl proapoptotic effects. Notably, the increase of NGB levels by NGB expression vector transfection prevents Pacl or Res/Pacl effects. Taken together, these findings indicate a new Res-based mechanism that acts on tumor cells impairing the E2/ERα/NGB signaling pathways and increasing cancer cell susceptibility to chemotherapeutic agent.

Defining the Roles of the Cation Diffusion Facilitators in Fe2+/Zn2+ Homeostasis and Establishment of Their Participation in Virulence in Pseudomonas aeruginosa.

Transporters of the cation diffusion facilitator (CDF) family form dimers that export transition metals from the cytosol. The opportunistic pathogen Pseudomonas aeruginosa encodes three homologous CDF genes, czcD (PA0397), aitP (PA1297), and yiiP (PA3963). The three proteins are required for virulence in a plant host model. Disruption of the aitP gene leads to higher Fe2+ and Co2+ sensitivity together with an intracellular accumulation of these ions and to a decreased survival in presence of H2O2. Strains lacking czcD and yiiP showed low Zn2+ sensitivity. However, in iron-rich media and in the presence of Zn2+ these strains secreted higher levels of the iron chelator pyoverdine. Disruption of czcD and yiiP in a non-pyoverdine producer strain and lacking the Zn2+-transporting ATPase, increased the Zn2+ sensitivity and the accumulation of this ion. Most importantly, independent of the pyoverdine production strains lacking CzcD or YiiP, presented lower resistance to imipenem, ciprofloxacin, chloramphenicol, and gentamicin. These observations correlated with a lower survival rate upon EDTA-lysozyme treatment and overexpression of OprN and OprD porins. We hypothesize that while AitP is an Fe2+/Co2+ efflux transporter required for Fe2+ homeostasis, and ultimately redox stress handling, CzcD, and YiiP export Zn2+ to the periplasm for proper Zn2+-dependent signaling regulating outer membrane stability and therefore antibiotic tolerance.

Consumptive and nonconsumptive effect ratios depend on interaction between plant quality and hunting behavior of omnivorous predators

SummaryPredators not only consume prey but exert nonconsumptive effects in form of scaring, consequently disturbing feeding or reproduction. However, how alternative food sources and hunting mode interactively affect consumptive and nonconsumptive effects with implications for prey fitness have not been addressed, impending functional understanding of such tritrophic interactions. With a herbivorous beetle, two omnivorous predatory bugs (plant sap as alternative food, contrasting hunting modes), and four willow genotypes (contrasting suitability for beetle/omnivore), we investigated direct and indirect effects of plant quality on the beetles key reproductive traits (oviposition rate, clutch size). Using combinations of either or both omnivores on different plant genotypes, we calculated the contribution of consumptive (eggs predated) and nonconsumptive (fewer eggs laid) effect on beetle fitness, including a prey density‐independent measure (c:nc ratio). We found that larger clutches increase egg survival in presence of the omnivore not immediately consuming all eggs. However, rather than lowering mean, the beetles generally responded with a frequency shift toward smaller clutches. However, female beetles decreased mean and changed clutch size frequency with decreasing plant quality, therefore reducing intraspecific exploitative competition among larvae. More importantly, variation in host plant quality (to omnivore) led to nonconsumptive effects between one‐third and twice as strong as the consumptive effects. Increased egg consumption on plants less suitable to the omnivore may therefore be accompanied by less searching and disturbing the beetle, representing a “cost” to the indirect plant defense in the form of a lower nonconsumptive effect. Many predators are omnivores and altering c:nc ratios (with egg retention as the most direct link to prey fitness) via plant quality and hunting behavior should be fundamental to advance ecological theory and applications. Furthermore, exploring modulation of fitness traits by bottom‐up and top‐down effects will help to explain how and why species aggregate.

Lose to win: marT pseudogenization in Salmonella enterica serovar Typhi contributed to the surV-dependent survival to H2O2, and inside human macrophage-like cells

The difference in host range between Salmonella enterica serovar Typhimurium (S. Typhimurium) and Salmonella enterica serovar Typhi (S. Typhi) can be partially attributed to the gain of functions, to the loss of functions (i.e. pseudogenization), or to a combination of both processes. As previously reported, the loss of functions by pseudogenization may play a role in bacterial evolution, especially in host-restricted pathogens such as S. Typhi. The marT-fidL operon, located at the SPI-3, encodes the MarT transcriptional regulator and a hypothetical protein (i.e. FidL) with no significant similarities to known proteins, respectively. Even though predicted S. Typhimurium FidL exhibit 99.4% identity with S. Typhi FidL, marT has been annotated as a pseudogene in S. Typhi. In this work, we found that S. Typhi expressing S. Typhimurium marT-fidL exhibited an increased accumulation of reactive oxygen species (ROS), leading to a decreased survival in presence of H2O2. Moreover, we found that that the presence of a functional copy of S. Typhimurium marT-fidL in S. Typhi resulted in a repression of surV (STY4039), an ORF found in the S. Typhi SPI-3 but absent from S. Typhimurium SPI-3, that contribute to the resistance to H2O2 by decreasing the accumulation of ROS. Finally, we observed that the presence of S. Typhimurium marT-fidL in S. Typhi negatively affected the survival inside macrophage-like cells, but not in epithelial cells, after 24h post infection. Therefore, this work provides evidence arguing that marT pseudogenization in Salmonella Typhi contributed to the surV-dependent survival against H2O2, and inside human macrophage-like cells. This is a good example of how the loss of functions (marT pseudogenization) and the gain of functions (presence of surV) might contribute to phenotypic changes improving virulence.

Probiotic traits of lactic acid bacteria isolated from aerial surfaces of pomegranate

Lactic acid bacteria isolated from aerial plant surfaces of pomegranate viz., Lactococcus lactis subsp. cremoris PB6, Lactobacillus brevis PFR77, L. lactis subsp. cremoris PFL9, Enterococcus faecium PB119 and L. lactis subsp. lactis PFL4 were tested for hemolysis, antibiotic susceptibility, gelatinase activity, tolerance to low pH and bile, resistance to digestive enzymes and antibacterial activity against human pathogens. All the isolates were non-hemolytic and non-gelatinolytic. These isolates were sensitive to clinically important antibiotics (amoxyclav, ampicillin, chloramphenicol, doxycycline, erythromycin, gentamycin, methicillin, penicillin G, Rifampicin and tetracycline), whereas resistance was recorded in case of norfloxacin and vancomycin. They could survive for more than 2h at pH 3 and the survival period of PB6, PFR77 and PFL9 was 3 h. Thus, the tolerance level of these LAB isolates was higher than the suggested values which indicate their good tolerance to stomach pH. In case of PB6, PFR77 and PFL9, around 80% of population survived in presence of 0.3% bile for 6 h. Also, they could survive at 1% concentration for 6 h. Thus, these isolates had good bile salt tolerance. All the isolates inhibited the growth of Gram positive and Gram negative bacterial pathogens with greater inhibition zones. PB6, PFR77 and PFL9 showed 60-70% survival in presence of trypsin whereas in presence of pepsin the survival decreased in between 50 and 60%. These isolates also showed good resistance to amylase and lipase. Thus, these LAB may be good candidates in formulation of probiotic preparations.

Abstract P5-07-06: A competing risks analysis of the association between prediagnostic serum glucose and lipids and breast cancer survival

Abstract Background: Abnormal levels of glucose and lipids may be linked to survival after breast cancer (BC) diagnosis, but their association to other causes of mortality such as cardiovascular (CV) disease may result in a competing risk problem and invalidate conventional analyses. Methods: We assessed serum glucose, triglycerides (TG) and total cholesterol (TC) measured prospectively three months to three years before diagnosis in 1,798 women with BC in the Swedish Apolipoprotein Mortality Risk Study (AMORIS). In addition to using multivariable Cox proportional hazards regression, we employed latent class proportional hazards models to capture any heterogeneity of associations between these markers and BC death. The latter method was extended to include the primary outcome (BC death) and competing outcomes (CV death and death from other causes), allowing latent class-specific hazard estimation for cause-specific deaths. Results: No association between prediagnostic glucose, TG or TC with BC death was observed with Cox regression. With latent class proportional hazards model, two latent classes (Class I and II) were identified in the cohort. Class I, comprising the majority (81.5%) of BC patients, had an increased risk of BC death following higher TG levels (HR: 1.87, 95% CI: 1.01-3.45 for every log TG increase). Lower overall survival was observed in Class II, but no association for BC death was found. On the other hand, TC positively corresponded to CV death in Class II, and similarly, glucose to death from other causes. Conclusion: Higher TG was associated with an increased risk of BC death in the majority of BC patients. Our study also identified a subgroup of BC patients at higher risk of early death likely driven by other metabolic-related diseases, which adds to our understanding into BC survival in presence of competing outcomes. Citation Format: Wulaningsih W, Vahdaninia M, Rowley M, Holmberg L, Garmo H, Malmstrom H, Lambe M, Hammar N, Walldius G, Jungner I, Coolen A, Van Hemelrijck M. A competing risks analysis of the association between prediagnostic serum glucose and lipids and breast cancer survival. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-07-06.

Glia-Neuron Interactions in the Retina Can Be Studied in Cocultures of Müller Cells and Retinal Ganglion Cells.

Glia-neuron partnership is important for inner retinal homeostasis and any disturbances may result in retinal ganglion cell (RGC) death. Müller cells support RGCs with essential functions such as removing excess glutamate and providing energy sources. The aim was to explore the impact of Müller cells on RGC survival. To investigate the Müller cell/RGC interactions we developed a coculture model, in which primary Müller cells were grown in inserts on top of pure primary RGC cultures. The impact of starvation and mitochondrial inhibition on the Müller cell ability to protect RGCs was studied. Moreover, the ability of Müller cells to remove glutamate from the extracellular space was investigated. RGC survival was evaluated by cell viability assays and glutamate uptake was assessed by kinetic uptake assays. We demonstrated a significantly increased RGC survival in presence of untreated and prestarved Müller cells. Additionally, prestarved Müller cells significantly increased RGC survival after mitochondrial inhibition. Finally, we revealed a significantly increased ability to take up glutamate in starved Müller cells. Overall, our study confirms essential roles of Müller cells in RGC survival. We suggest that targeting Müller cell function could have potential for future treatment strategies to prevent blinding neurodegenerative retinal diseases.

Conditional Reduction of Predation Risk Associated with a Facultative Symbiont in an Insect

Symbionts are widespread among eukaryotes and their impacts on the ecology and evolution of their hosts are meaningful. Most insects harbour obligate and facultative symbiotic bacteria that can influence their phenotype. In the pea aphid Acyrthosiphon pisum, an astounding symbiotic-mediated phenotype has been recently observed: when infected with the symbiotic bacteria Rickettsiella viridis, young red aphid larvae become greener at adulthood and even darker green when co-infected with Rickettsiella viridis and Hamiltonella defensa. As body colour affects the susceptibility towards natural enemies in aphids, the influence of the colour change due to these facultative symbionts on the host survival in presence of predators was tested. Our results suggested that the Rickettsiella viridis infection may impact positively host survival by reducing predation risk. Due to results from uninfected aphids (i.e., more green ones attacked), the main assumption is that this symbiotic infection would deter the predatory ladybird feeding by reducing the profitability of their hosts rather than decreasing host detection through body colour change. Aphids co-infected with Rickettsiella viridis and Hamiltonella defensa were, however, more exposed to predation suggesting an ecological cost associated with multiple infections. The underlying mechanisms and ecological consequences of these symbiotic effects are discussed.

MGMT-STP27 Methylation Status as Predictive Marker for Response to PCV in Anaplastic Oligodendrogliomas and Oligoastrocytomas. A Report from EORTC Study 26951

The long-term follow-up results from the EORTC-26951 trial showed that the addition of procarbazine, CCNU, and vincristine (PCV) after radiotherapy increases survival in anaplastic oligodendrogliomas/oligoastrocytomas (AOD/AOA). However, some patients appeared to benefit more from PCV treatment than others. We conducted genome-wide methylation profiling of 115 samples included in the EORTC-26951 trial and extracted the CpG island hypermethylated phenotype (CIMP) and MGMT promoter methylation (MGMT-STP27) status. We first show that methylation profiling can be conducted on archival tissues with a performance that is similar to snap-frozen tissue samples. We then conducted methylation profiling on EORTC-26951 clinical trial samples. Univariate analysis indicated that CIMP+ or MGMT-STP27 methylated tumors had an improved survival compared with CIMP- and/or MGMT-STP27 unmethylated tumors [median overall survival (OS), 1.05 vs. 6.46 years and 1.06 vs. 3.8 years, both P < 0.0001 for CIMP and MGMT-STP27 status, respectively]. Multivariable analysis indicates that CIMP and MGMT-STP27 are significant prognostic factors for survival in presence of age, sex, performance score, and review diagnosis in the model. CIMP+ and MGMT-STP27 methylated tumors showed a clear benefit from adjuvant PCV chemotherapy: the median OS of CIMP+ samples in the RT and RT-PCV arms was 3.27 and 9.51 years, respectively (P = 0.0033); for MGMT-STP27 methylated samples, it was 1.98 and 8.65 years. There was no such benefit for CIMP- or for MGMT-STP27 unmethylated tumors. MGMT-STP27 status remained significant in an interaction test (P = 0.003). Statistical analysis of microarray (SAM) identified 259 novel CpGs associated with treatment response. MGMT-STP27 may be used to guide treatment decisions in this tumor type.

SIRT1 silencing confers neuroprotection through IGF‐1 pathway activation

The following study demonstrated that, in in vitro differentiated neurons, SIRT1 silencing induced an increase of IGF-1 protein expression and secretion and of IGF-1R protein levels which, in turn, prolonged neuronal cell survival in presence of an apoptotic insult. On the contrary, SIRT1 overexpression increased cell death. In particular, IGF-1 and IGF-1R expression levels were negatively regulated by SIRT1. In SIRT1 silenced cells, the increase in IGF-1 and IGF-1R expression was associated to an increase in AKT and ERK1/2 phosphorylation. Moreover, neuronal differentiation was reduced in SIRT1 overexpressing cells and increased in SIRT1 silenced cells. We conclude that SIRT1 silenced neurons appear more committed to differentiation and more resistant to cell death through the activation of IGF-1 survival pathway.

Notch-3 and Notch-4 signaling rescue from apoptosis human B-ALL cells in contact with human bone marrow–derived mesenchymal stromal cells

AbstractAlthough many literature data are available on the role of Notch signaling in T-cell acute lymphoblastic leukemia (ALL) biology, the importance of this molecular pathway in the development of B-lineage ALL (B-ALL) cells in the BM microenvironment is unknown so far. In this study, we used anti-Notch molecules neutralizing Abs and γ-secretase inhibitor (GSI) XII to investigate the role of the Notch signaling pathway in the promotion of human B-ALL cell survival in presence of stromal cell support. The treatment with combinations of anti-Notch molecule neutralizing Abs resulted in the decrease of B-ALL cell survival, either cultured alone or cocultured in presence of stromal cells from normal donors and B-ALL patients. Interestingly, the inhibition of Notch-3 and -4 or Jagged-1/-2 and DLL-1 resulted in a dramatic increase of apoptotic B-ALL cells by 3 days, similar to what is obtained by blocking all Notch signaling with the GSI XII. Our data suggest that the stromal cell–mediated antiapoptotic effect on B- ALL cells is mediated by Notch-3 and -4 or Jagged-1/-2 and DLL-1 in a synergistic manner.

Dlxin-1, a MAGE family protein, induces accelerated neurite outgrowth and cell survival by enhanced and early activation of MEK and Akt signalling pathways in PC12 cells

Dlxin-1 (also known as NRAGE or MAGED1) is a member of Type II melanoma-associated antigen (MAGE) family of proteins characterized by presence of a unique region of about 200 amino acids known as the MAGE homology domain (MHD). Dlxin-1 is associated with a large number of diverse cellular functions ranging from transcriptional regulation, cell cycle progression and differentiation to developmental apoptosis. While there are numerous studies reporting the role of NRAGE in facilitating cell death by interaction with p75NTR, we found varied effects of Dlxin-1 over-expression on PC12 cells grown in presence of NGF. These include induction of increased cell survival in presence of NGF and accelerated neuronal differentiation. We here categorically demonstrate that the effects on neuritogenesis are promoted through interactions of Dlxin-1 with the neurotrophin receptor TrkA. Further, using pharmacological inhibitors to specific pathways, we delineate the effects on enhanced neuritogenesis to the early and sustained activation of MEK pathway whereas the effects on cell survival to the early activation of Akt pathway. Next, we demonstrate a physical interaction of necdin with Dlxin-1 in PC12 cells. Our results establish that Dlxin-1 is an enhancer of neuronal differentiation and suggests that its possible interaction with NGF and necdin is critical in mediating pathways involved in neuronal survival and differentiation. Further in-depth analyses of the activation of various signalling pathways mediated through interaction with Dlxin-1 may provide valuable insight on the mechanisms that govern decisions regarding neuronal survival, growth, differentiation or apoptosis.