A sumoylation program is essential for maintaining the mitotic fidelity in proliferating mantle cell lymphoma cells

BACKGROUND

Mantle cell lymphoma (MCL) is a rare, highly heterogeneous type of B-cell non-Hodgkin's lymphoma. The sumoylation pathway is known to be upregulated in many cancers including lymphoid malignancies. However, little is known about its oncogenic role in MCL.

METHODS

Levels of sumoylation enzymes and sumoylated proteins were quantified in MCL cell lines and primary MCL patient samples by scRNA sequencing and immunoblotting. The sumoylation enzyme SAE2 was genetically and pharmacologically targeted with shRNA and TAK-981 (subasumstat). The effects of SAE2 inhibition on MCL proliferation and cell cycle were evaluated using confocal microscopy, live-cell microscopy, and flow cytometry. Immunoprecipitation and orbitrap mass spectrometry were used to identify proteins targeted by sumoylation in MCL cells.

RESULTS

MCL cells have significant upregulation of the sumoylation pathway at the level of the enzymes SAE1 and SAE2 which correlated with poor prognosis and induction of mitosis associated genes. Selective inhibition of SAE2 with TAK-981 results in significant MCL cell death in vitro and in vivo with mitotic dysregulation being an important mechanism of action. We uncovered a sumoylation program in mitotic MCL cells comprised of multiple pathways which could be directly targeted with TAK-981. Centromeric localization of topoisomerase 2A, a gene highly upregulated in SAE1 and SAE2 overexpressing MCL cells, was lost with TAK-981 treatment likely contributing to the mitotic dysregulation seen in MCL cells.

CONCLUSIONS

This study not only validates SAE2 as a therapeutic target in MCL but also opens the door to further mechanistic work to uncover how to best use desumoylation therapy to treat MCL and other lymphoid malignancies.

To Assess the Cardio Respiratory Endurance in College Going Students- An Observational Study

Background: Sub-maximal exercise test is very useful in evaluatingindividual’s cardio-respiratory fitness. Many factors haveimpact on distance walked during six-minute walk test and consideredto be ideal for patient population.Methods: 100 young college going male and female subjectssatisfying inclusion criteria performed six-minute walk test andvital parameters, prior to test and post test at regular intervaltill 3 minutes were taken. Body Mass Index (BMI) was calculated.Results: 20 male and 80 female subjects performed six-minute walktest. The mean distance walked by males was 534.24 meters whereasmean distance walked by female subjects was 506.7 meters.Conclusion: It was observed that college going healthy subjectshave normal cardio-respiratory endurance.

Multiplex PCR based genotypic characterization of pathogenic vancomycin resistant Enterococcus faecalis recovered from an Indian river along a city landscape

BACKGROUND

Enterococci are normal commensals of human gut, but vancomycin-resistant enterococci (VRE) are a severe threat to human health. Antimicrobial-resistant enterococci have been reported previously from Indian surface waters. However, the presence of antimicrobial resistance and virulence markers in Enterococcus faecalis, the most dominant enterococci is yet to be investigated.

OBJECTIVES

The goal of this study was to analyse concentration of enterococci and distribution of antimicrobial resistance and virulence markers in E. faecalis isolates from river waters along an important north Indian city landscape.

METHODS

We enumerated enterococci in river water samples (n = 60) collected from five sites across the Lucknow city landscape using the most probable number and membrane-filtration methods. The antimicrobial sensitivity profile of E. faecalis isolate was generated with the Kirby-Bauer antimicrobial disc diffusion assay. The multiplex PCR was used for genotypic characterization of vancomycin-resistance and virulence in E. faecalis isolates.

RESULTS

Enterococci density (p < 0.0001) increased from up-to-down-stream sites. Multiplex PCR based genotypic characterization has shown a significant distribution of virulence-markers gelE, ace or efaA in the E. faecalis isolates (p < 0.05). The range of antimicrobial-resistance varied from 5 to 12 in the landscape with the frequency of vancomycin-resistant E. faecalis (VRE) ranging from 22 to 100 %.

CONCLUSION

The occurrence of pathogenic VRE in river Gomti surface water is an important health concern. The observed high background pool of resistance and virulence in E. faecalis in river waters has the potential to disseminate more alarming antimicrobial resistance in the environment and poses serious health risk in developing countries like India as VRE infections could lead to increased cost of healthcare.

HO-3867, a safe STAT3 inhibitor, is selectively cytotoxic to ovarian cancer

STAT3 is well corroborated preclinically as a cancer therapeutic target, but tractable translational strategies for its blockade by small molecule inhibitors have remained elusive. In this study, we report the development of a novel class of bifunctional STAT3 inhibitors, based on conjugation of a diarylidenyl-piperidone (DAP) backbone to an N-hydroxypyrroline (-NOH) group, which exhibits minimal toxicity against normal cells and good oral bioavailability. Molecular modeling studies of this class suggested direct interaction with the STAT3 DNA binding domain. In particular, the DAP compound HO-3867 selectively inhibited STAT3 phosphorylation, transcription, and DNA binding without affecting the expression of other active STATs. HO-3867 exhibited minimal toxicity toward noncancerous cells and tissues but induced apoptosis in ovarian cancer cells. Pharmacologic analysis revealed greater bioabsorption and bioavailability of the active (cytotoxic) metabolites in cancer cells compared with normal cells. The selective cytotoxicity of HO-3867 seemed to be multifaceted, eliciting differential activation of the Akt pathway in normal versus cancer cells. RNAi attenuation experiments confirmed the requirement of STAT3 for HO-3867-mediated apoptosis in ovarian cancer cells. In vivo testing showed that HO-3867 could block xenograft tumor growth without toxic side effects. Furthermore, in primary human ovarian cancer cells isolated from patient ascites, HO-3867 inhibited cell migration/invasion and survival. Our results offer preclinical proof-of-concept for HO-3867 as a selective STAT3 inhibitor to treat ovarian cancer and other solid tumors where STAT3 is widely upregulated.

Abstract 1039: HO-3867, is selectively cytotoxic to ovarian cancer cells through a dual mechanism of action involving the STAT3 and AKT pathways

Objective: The development of anticancer drugs that selectively kills cancer cells while sparing the surrounding healthy tissues is of paramount importance for safe and effective anti-cancer therapy. We have developed a novel class of compounds that are fluoro-substituted analogs of curcumin, called diarylidenylpiperiden-4-ones (DAPs). We hypothesize that the structural backbone of DAP compounds would have cytotoxic activity, and the -NOH moiety would function as a tissue-specific modulator of this cytotoxicity via its anti-oxidant properties. The goal of this study was to analyze the differential cytotoxic effects of one of these compounds, HO-3867, on both ovarian cancer and normal cells.

Methods: Protein expression in pro-apoptotic and survival signaling pathways were analyzed via western blotting, and immunofluorescence assays using human ovarian cancer (SKOV-3) and normal ovarian surface epithelial (hOSE) cell lines treated with 10 μM HO-3867. Flow cytometry was used to quantify apoptosis and immunohistochemistry was performed to analyze cellular localization of proteins. The selective cytotoxic effect of HO-3867 was verified using STAT3 cDNA and Akt siRNA transfection. In vivo analysis was performed on mice administered oral HO-3867 using histopathological analysis and TUNEL assays. Efficacy of HO-3867 proved in STAT3 knockdown SKOV3 ovarian cancer cell line.

Results: HO-3867 did not affect the proliferation rate of hOSE cells while showing potent cytotoxic activity against SKOV-3 cells. In vivo histopathological evaluation of internal organs collected from treated adult mice revealed no evidence of toxicity. TUNEL staining of collected tissues suggested that selective apoptotic induction was limited to neoplastic cells in tumor xenografts. HO-3867 protected the normal cells by up-regulating the pro-survival protein pAkt. Tumor cells were targeted through downregulation of pAkt, pStat3, pErk1/2 and Bcl2 and upregulation of p21 and p53. Furthermore, HO-3867 was selectively regulates kinase activity in ovarian cancer cells and compared with hOSE cells. In addition, HO-3867 treated into STAT3 knockdown SKOV3 cells, resulted in the decreased apoptosis. These data indicated that HO-3867 induced apoptosis through the targeting STAT3.

Conclusion: Our results showed that HO-3867 protects normal cells while retaining antiproliferative activity against ovarian cancer cells. Increased levels of pAkt and the free radical-scavenging effects of the pro-nitroxide N-hydroxypyrroline group mediate this selective protection. The results suggest that the antioxidant-conjugated DAPs may be useful as safe and effective anticancer agents for treatment of ovarian cancer

Citation Format: Georgia A. McCann, Kellie S. Rath, Shan Naidu, Pushpa Lata, Bid Hemant, Meryl Sudhakar, Kálmán Hideg, Peter Houghton, Periannan Kuppusamy, David E. Cohn, Karuppaiyah Selvendiran. HO-3867, is selectively cytotoxic to ovarian cancer cells through a dual mechanism of action involving the STAT3 and AKT pathways . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1039. doi:10.1158/1538-7445.AM2013-1039

Enterococci in river Ganga surface waters: propensity of species distribution, dissemination of antimicrobial-resistance and virulence-markers among species along landscape

Background

Surface waters quality has declined in developing countries due to rapid industrialization and population growth. The microbiological quality of river Ganga, a life-sustaining surface water resource for large population of northern India, is adversely affected by several point and non-point sources of pollution. Further, untreated surface waters are consumed for drinking and various household tasks in India making the public vulnerable to water-borne diseases and outbreaks. Enterococci, the 'indicator' of water quality, correlates best with the incidence of gastrointestinal diseases as well as prevalence of other pathogenic microorganisms. Therefore, this study aims to determine the distribution of species diversity, dissemination of antimicrobial-resistance and virulence-markers in enterococci with respect to rural-urban landscape along river Ganga in northern India.

Results

Enterococci density (χ²: 1900, df: 1; p < 0.0001) increased from up-to-down gradient sites in the landscape. Species diversity exhibit significant (χ²: 100.4, df: 20; p < 0.0001) and progressive distribution of E. faecalis, E. faecium, E. durans and E. hirae down the gradient. Statistically discernible (p: 0.0156 – < 0.0001) background pool of resistance and virulence was observed among different Enterococcus spp. recovered from five sites in the up-to-down gradient landscape. A significant correlation was observed in the distribution of multiple-antimicrobial-resistance (viz., erythromycin-rifampicin-gentamicin-methicillin and vancomycin-gentamicin-streptomycin; r_s: 0.9747; p: 0.0083) and multiple-virulence-markers (viz., gelE⁺esp⁺; r_s: 0.9747; p: 0.0083; gelE⁺efaA⁺; r_s: 0.8944; p: 0.0417) among different Enterococcus spp.

Conclusion

Our observations show prevalence of multiple-antimicrobial-resistance as well as multiple-virulence traits among different Enterococcus spp. The observed high background pool of resistance and virulence in enterococci in river waters of populous countries has the potential to disseminate more alarming antimicrobial-resistant pathogenic bacteria of same or other lineage in the environment. Therefore, the presence of elevated levels of virulent enterococci with emerging vancomycin resistance in surface waters poses serious health risk in developing countries like India.

Real time PCR for the rapid detection of vanA gene in surface waters and aquatic macrophyte by molecular beacon probe

Enterococci serve as an "indicator" of fecal contamination for recreational water quality. The vancomycin-resistant-enterococci (VRE) are emerging environmental contaminants in the surface waters. The aim ofthis study wasto develop a rapid and specific molecular beacon probe (MBP)-based real-time PCR assay for detection of vanA gene in surface waters and aquatic macrophyte. The limit of detection (LOD) of the MBP assay was 1 CFU/mL of VRE [r = 0.943; PCR efficiency = 99.7%] in 2-fold dilution format within 2.5 h and demonstrated high specificityfor environmental enterococci isolates exhibiting VanA phenotype (n=25). VRE were detected from downstream surface waters of the rivers impacted by point sources of pollution and recreational activities.The probe detected vanA gene in rootmat associated microbiota of E. crassipes (Mart) Solms. an aquatic nuisance weed, at eutrophic sites of the surface waters (ANOVA p < 0.001). In addition, the assay enabled detection of otherwise nondetectable vanA gene concentration in the upstream sites of two Indian rivers (Student's ttest p < 0.001). The MBP assay developed can be used for sensitive and rapid detection of VRE in surface waters and identification of nonpoint sources of pollution for implementation of preventive measures to protect human health.

Management of translocated and incarcerated intrauterine contraceptive devices

Thirty-seven consecutive patients who reported with absent or snapped strings and failed attempts at removal of intrauterine contraceptive devices (IUCD) by hooks or curette were posted for hysteroscopy/laparotomy following a plain X-ray of the pelvis to exclude unrecognized spontaneous expulsion. Direct visualization of the endometrial cavity was invaluable in locating and removing IUCDs, particularly the embedded and fragmented ones. Translocated medicated devices were associated with dense adhesions, suggesting the need for their prompt removal. There appears to be an increased risk of translocation in lactating women.