A Panel-Based Mutational Signature of Mismatch Repair Deficiency is Associated With Durable Response to Pembrolizumab in Metastatic Castration-Resistant Prostate Cancer

INTRODUCTION/BACKGROUND

Immune checkpoint inhibitors (ICIs) have limited efficacy in prostate cancer (PCa). Better biomarkers are needed to predict responses to ICIs. We sought to demonstrate that a panel-based mutational signature identifies mismatch repair (MMR) deficient (MMRd) PCa and is a biomarker of response to pembrolizumab.

PATIENTS AND METHODS

Clinico-genomic data was obtained for 2664 patients with PCa sequenced at Dana-Farber Cancer Institute (DFCI) and Memorial Sloan Kettering (MSK). Clinical outcomes were collected for patients with metastatic castration-resistant PCa (mCRPC) treated with pembrolizumab at DFCI. SigMA was used to characterize tumors as MMRd or MMR proficient (MMRp). The concordance between MMRd with microsatellite instability (MSI-H) was assessed. Radiographic progression-free survival (rPFS) and overall survival (OS) were collected for patients treated with pembrolizumab. Event-time distributions were estimated using Kaplan-Meier methodology.

RESULTS

Across both cohorts, 100% (DFCI: 12/12; MSK: 43/43) of MSI-H tumors were MMRd. However, 14% (2/14) and 9.1% (6/66) of MMRd tumors in the DFCI and MSK cohorts respectively were microsatellite stable (MSS), and 26% (17/66) were MSI-indeterminate in the MSK cohort. Among patients treated with pembrolizumab, those with MMRd (n = 5) versus MMRp (n = 14) mCRPC experienced markedly improved rPFS (HR = 0.088, 95% CI: 0.011-0.70; P = .0064) and OS (HR = 0.11, 95% CI: 0.014-0.80; P = .010) from start of treatment. Four patients with MMRd experienced remissions of >= 2.5 years.

CONCLUSION

SigMA detects additional cases of MMRd as compared to MSI testing in PCa and identifies patients likely to experience durable response to pembrolizumab.

First report of molecular confirmation and phylogenetic analysis of ocular seteriasis in buffalo in India using 12S rRNA

An adult Indian buffalo (Bubalus bubalis) presented with corneal opacity, irritation, and excessive lacrimation from the left eye in the Referral Veterinary Polyclinic-Teaching Veterinary Clinical Complex (RVC-TVCC), Indian Veterinary Research Institute, Izatnagar. Clinical examination revealed a whitish thread-like worm in the left eye's anterior chamber. The worm was surgically removed from the eye with supportive nerve blocks. Light microscopy was used for parasite morphological identification, which provided insight into the worm as female Setaria sp. Genomic DNA was isolated, and polymerase chain reaction amplification of 12S rRNA was conducted for molecular confirmation of the parasite. The amplicon was sequenced and analysed by bioinformatics software. Sequence data showed an amplicon size of 243 bp. Phylogenetic analysis with reference data from the NCBI Genbank database revealed the worm was S. digitata, with a similarity of 99.17%. The common predilection site of S. digitata is in the peritoneal cavity of natural hosts like cattle and buffalo and is mostly non-pathogenic. The aberrant migration of the parasite larva to the brain and eye commonly occurs in goats, sheep, and horses, causing clinical conditions like cerebrospinal nematodiasis (lumbar paralysis) and ocular setariasis, respectively. Nevertheless, until now, there have been no reports of ocular setariasis in buffalo. This report is the first unusual occurrence of ocular setariasis in buffalo and its molecular confirmation and phylogenetic analysis using 12S rRNA.

Analysis of evolutionary dynamics and clonal architecture in prostate cancer

The extent to which clinical and genomic characteristics associate with prostate cancer clonal architecture, tumor evolution, and therapeutic response remains unclear. Here, we reconstructed the clonal architecture and evolutionary trajectories of 845 prostate cancer tumors with harmonized clinical and molecular data. We observed that tumors from patients who self-reported as Black had more linear and monoclonal architectures, despite these men having higher rates of biochemical recurrence. This finding contrasts with prior observations relating polyclonal architecture to adverse clinical outcomes. Additionally, we utilized a novel approach to mutational signature analysis that leverages clonal architecture to uncover additional cases of homologous recombination and mismatch repair deficiency in primary and metastatic tumors and link the origin of mutational signatures to specific subclones. Broadly, prostate cancer clonal architecture analysis reveals novel biological insights that may be immediately clinically actionable and provide multiple opportunities for subsequent investigation.

Statement of significance

Tumors from patients who self-reported as Black demonstrate linear and monoclonal evolutionary trajectories yet experience higher rates of biochemical recurrence. In addition, analysis of clonal and subclonal mutational signatures identifies additional tumors with potentially actionable alterations such as deficiencies in mismatch repair and homologous recombination.

Oriental theileriosis associated with a new genotype of Theileria orientalis in buffalo (Bubalus bubalis) calves in Uttar Pradesh, India

Theileria orientalis is known to cause a benign infection in cattle and buffalo (Bubalus bubalis). However, the Ikeda and Chitose genotypes of the parasite cause lethal disease in beef and dairy cattle. Recently an outbreak of clinical oriental theileriosis occurred in buffalo calves in a Government Animal Husbandry and Agricultural Farm located in Uttar Pradesh, India. Examination of Giemsa stained thin blood smears revealed typical rod-shaped T. orientalis piroplasms in the erythrocytes. The clinical signs included pyrexia, nasal discharge, lacrimation, lethargy, inappetence and anaemia with varying degrees of paleness of the visible mucous membranes. Vascular congestion in internal organs, pulmonary emphysema and consolidation of lungs, focal areas of necrosis in the heart with mononuclear cell infiltration, focal mononuclear cell aggregation in the cortex and tubular degeneration of the kidney were significant necropsy findings. The T. orientalis major piroplasm surface protein (MPSP) gene was amplified by polymerase chain reaction (PCR) using specific primers. The nucleotide sequence analysis of the PCR product revealed 84.8% identity between the T. orientalis Uttar Pradesh isolate and other reference genotypes available in the public domain. Furthermore, the phylogenetic analysis of the MPSP gene sequence ratified that this is a new genotype of T. orientalis. This is the first report of a clinical outbreak of oriental theileriosis in Indian buffalo calves caused by a novel genotype of T. orientalis.

Addition of Germline Testing to Tumor-Only Sequencing Improves Detection of Pathogenic Germline Variants in Men With Advanced Prostate Cancer

PURPOSE

Guidelines recommend somatic and germline testing for men with advanced prostate cancer (PCa). Barriers to widespread implementation result in underutilization of germline testing. Somatic testing alone risks missing pathogenic germline variants (PGVs). We sought to determine whether the addition of germline testing to tumor-only sequencing improves detection of PGVs in men with advanced PCa. Secondarily, we sought to define the added value of combining somatic and germline testing to optimize detection of clinically actionable alterations.

PATIENTS AND METHODS

We analyzed results of independent germline testing and tumor-only sequencing from 100 men with advanced PCa from a prospective clinical trial (ClinicalTrials.gov identifier: NCT03328091). The primary outcome was the proportion of PGVs not reported with tumor-only sequencing. The secondary outcome was the association of locus-specific loss of heterozygosity for PGVs in homologous recombination genes with clinical-genomic features.

RESULTS

In the 100 men who underwent germline testing and tumor-only sequencing, 24 PGVs were identified, 17 of which were clinically actionable, in 23 patients. Tumor-only sequencing failed to report four (17%) of the PGVs. One additional PGV (4.2%) had variant allele frequency on tumor-sequencing below the threshold for follow-up germline testing. When integrating tumor-only sequencing with germling testing results, 33% of patients harbored clinically actionable alterations. Rates of locus-specific loss of heterozygosity were higher for BRCA2 PGVs in castration-resistant PCa than PGVs in other homologous recombination genes in hormone-sensitive PCa (P = .029).

CONCLUSION

Tumor-only sequencing failed to report more than 20% of PGVs in men with advanced PCa. These findings strongly support guideline recommendations for universal germline and somatic testing in this population. Combining tumor and germline sequencing doubled the chance of detecting a clinically actionable alteration.

Profiling the quantitative occupancy of myriad transcription factors across conditions by modeling chromatin accessibility data

Over a thousand different transcription factors (TFs) bind with varying occupancy across the human genome. Chromatin immunoprecipitation (ChIP) can assay occupancy genome-wide, but only one TF at a time, limiting our ability to comprehensively observe the TF occupancy landscape, let alone quantify how it changes across conditions. We developed TOP, a Bayesian hierarchical regression framework, to profile genome-wide quantitative occupancy of numerous TFs using data from a single chromatin accessibility experiment (DNase- or ATAC-seq). TOP is supervised, and its hierarchical structure allows it to predict the occupancy of any sequence-specific TF, even those never assayed with ChIP. We used TOP to profile the quantitative occupancy of hundreds of sequence-specific TFs at sites throughout the genome, and examined how their occupancies changed in multiple contexts: in ~200 human cell types, through 12 hours of exposure to different hormones, and across the genetic backgrounds of 70 individuals. TOP enables cost-effective exploration of quantitative changes in the landscape of TF binding.

FGFR-inhibitor-mediated dismissal of SWI/SNF complexes from YAP-dependent enhancers induces adaptive therapeutic resistance

How cancer cells adapt to evade the therapeutic effects of drugs targeting oncogenic drivers is poorly understood. Here we report an epigenetic mechanism leading to the adaptive resistance of triple-negative breast cancer (TNBC) to fibroblast growth factor receptor (FGFR) inhibitors. Prolonged FGFR inhibition suppresses the function of BRG1-dependent chromatin remodelling, leading to an epigenetic state that derepresses YAP-associated enhancers. These chromatin changes induce the expression of several amino acid transporters, resulting in increased intracellular levels of specific amino acids that reactivate mTORC1. Consistent with this mechanism, addition of mTORC1 or YAP inhibitors to FGFR blockade synergistically attenuated the growth of TNBC patient-derived xenograft models. Collectively, these findings reveal a feedback loop involving an epigenetic state transition and metabolic reprogramming that leads to adaptive therapeutic resistance and provides potential therapeutic strategies to overcome this mechanism of resistance.

Subtype heterogeneity and epigenetic convergence in neuroendocrine prostate cancer

Neuroendocrine carcinomas (NEC) are tumors expressing markers of neuronal differentiation that can arise at different anatomic sites but have strong histological and clinical similarities. Here we report the chromatin landscapes of a range of human NECs and show convergence to the activation of a common epigenetic program. With a particular focus on treatment emergent neuroendocrine prostate cancer (NEPC), we analyze cell lines, patient-derived xenograft (PDX) models and human clinical samples to show the existence of two distinct NEPC subtypes based on the expression of the neuronal transcription factors ASCL1 and NEUROD1. While in cell lines and PDX models these subtypes are mutually exclusive, single-cell analysis of human clinical samples exhibits a more complex tumor structure with subtypes coexisting as separate sub-populations within the same tumor. These tumor sub-populations differ genetically and epigenetically contributing to intra- and inter-tumoral heterogeneity in human metastases. Overall, our results provide a deeper understanding of the shared clinicopathological characteristics shown by NECs. Furthermore, the intratumoral heterogeneity of human NEPCs suggests the requirement of simultaneous targeting of coexisting tumor populations as a therapeutic strategy.

Neuroendocrine carcinomas (NECs) arise from different anatomic sites, but have similar histological and clinical features. Here, the authors show that the epigenetic landscape of a range of NECs converges towards a common epigenetic state, while distinct subtypes occur within neuroendocrine prostate cancer contributing to intratumor heterogeneity in clinical samples.

Molecular features of exceptional response to neoadjuvant anti-androgen therapy in high-risk localized prostate cancer

High-risk localized prostate cancer (HRLPC) is associated with a substantial risk of recurrence and disease mortality. Recent clinical trials have shown that intensifying anti-androgen therapies administered before prostatectomy can induce pathologic complete responses or minimal residual disease, called exceptional response, although the molecular determinants of these clinical outcomes are largely unknown. Here, we perform whole-exome and transcriptome sequencing on pre-treatment multi-regional tumor biopsies from exceptional responders (ERs) and non-responders (NRs, pathologic T3 or lymph node-positive disease) to intensive neoadjuvant anti-androgen therapies. Clonal SPOP mutation and SPOPL copy-number loss are exclusively observed in ERs, while clonal TP53 mutation and PTEN copy-number loss are exclusively observed in NRs. Transcriptional programs involving androgen signaling and TGF-β signaling are enriched in ERs and NRs, respectively. These findings may guide prospective validation studies of these molecular features in large HRLPC clinical cohorts treated with neoadjuvant anti-androgens to improve patient stratification.

Tumor and immune reprogramming during immunotherapy in advanced renal cell carcinoma

Immune checkpoint blockade (ICB) results in durable disease control in a subset of patients with advanced renal cell carcinoma (RCC), but mechanisms driving resistance are poorly understood. We characterize the single-cell transcriptomes of cancer and immune cells from metastatic RCC patients before or after ICB exposure. In responders, subsets of cytotoxic T cells express higher levels of co-inhibitory receptors and effector molecules. Macrophages from treated biopsies shift toward pro-inflammatory states in response to an interferon-rich microenvironment but also upregulate immunosuppressive markers. In cancer cells, we identify bifurcation into two subpopulations differing in angiogenic signaling and upregulation of immunosuppressive programs after ICB. Expression signatures for cancer cell subpopulations and immune evasion are associated with PBRM1 mutation and survival in primary and ICB-treated advanced RCC. Our findings demonstrate that ICB remodels the RCC microenvironment and modifies the interplay between cancer and immune cell populations critical for understanding response and resistance to ICB.

Therapeutically Increasing MHC-I Expression Potentiates Immune Checkpoint Blockade

Immune checkpoint blockade (ICB) therapy revolutionized cancer treatment, but many patients with impaired MHC-I expression remain refractory. Here, we combined FACS-based genome-wide CRISPR screens with a data-mining approach to identify drugs that can upregulate MHC-I without inducing PD-L1. CRISPR screening identified TRAF3, a suppressor of the NFκB pathway, as a negative regulator of MHC-I but not PD-L1. The Traf3-knockout gene expression signature is associated with better survival in ICB-naïve patients with cancer and better ICB response. We then screened for drugs with similar transcriptional effects as this signature and identified Second Mitochondria-derived Activator of Caspase (SMAC) mimetics. We experimentally validated that the SMAC mimetic birinapant upregulates MHC-I, sensitizes cancer cells to T cell-dependent killing, and adds to ICB efficacy. Our findings provide preclinical rationale for treating tumors expressing low MHC-I expression with SMAC mimetics to enhance sensitivity to immunotherapy. The approach used in this study can be generalized to identify other drugs that enhance immunotherapy efficacy. SIGNIFICANCE: MHC-I loss or downregulation in cancer cells is a major mechanism of resistance to T cell-based immunotherapies. Our study reveals that birinapant may be used for patients with low baseline MHC-I to enhance ICB response. This represents promising immunotherapy opportunities given the biosafety profile of birinapant from multiple clinical trials.This article is highlighted in the In This Issue feature, p. 1307.

Transcriptional mediators of treatment resistance in lethal prostate cancer

Metastatic castration-resistant prostate cancer is typically lethal, exhibiting intrinsic or acquired resistance to second-generation androgen-targeting therapies and minimal response to immune checkpoint inhibitors¹. Cellular programs driving resistance in both cancer and immune cells remain poorly understood. We present single-cell transcriptomes from 14 patients with advanced prostate cancer, spanning all common metastatic sites. Irrespective of treatment exposure, adenocarcinoma cells pervasively coexpressed multiple androgen receptor isoforms, including truncated isoforms hypothesized to mediate resistance to androgen-targeting therapies^2,3. Resistance to enzalutamide was associated with cancer cell-intrinsic epithelial-mesenchymal transition and transforming growth factor-β signaling. Small cell carcinoma cells exhibited divergent expression programs driven by transcriptional regulators promoting lineage plasticity and HOXB5, HOXB6 and NR1D2 (refs. ^4-6). Additionally, a subset of patients had high expression of dysfunction markers on cytotoxic CD8⁺ T cells undergoing clonal expansion following enzalutamide treatment. Collectively, the transcriptional characterization of cancer and immune cells from human metastatic castration-resistant prostate cancer provides a basis for the development of therapeutic approaches complementing androgen signaling inhibition.

Urine Extracellular Vesicle GATA2 mRNA Discriminates Biopsy Result in Men with Suspicion of Prostate Cancer

PURPOSE

Prostate specific antigen has limited performance in detecting prostate cancer. The transcription factor GATA2 is expressed in aggressive prostate cancer. We analyzed the predictive value of urine extracellular vesicle GATA2 mRNA alone and in combination with a multigene panel to improve detection of prostate cancer and high risk disease.

MATERIALS AND METHODS

GATA2 mRNA was analyzed in matched extracellular vesicles isolated from urines before and after prostatectomy (16) and paired urine and tissue prostatectomy samples (19). Extracellular vesicle GATA2 mRNA performance to distinguish prostate cancer and high grade disease was tested in training (52) and validation (165) cohorts. The predictive value of a multigene score including GATA2, PCA3 and TMPRSS2-ERG (GAPT-E) was tested in both cohorts.

RESULTS

Confirming its prostate origin, urine extracellular vesicle GATA2 mRNA levels decreased significantly after prostatectomy and correlated with prostate cancer tissue GATA2 mRNA levels. In the training and validation cohort GATA2 discriminated prostate cancer (AUC 0.74 and 0.66) and high grade disease (AUC 0.78 and 0.65), respectively. Notably, the GAPT-E score improved discrimination of prostate cancer (AUC 0.84 and 0.72) and high grade cancer (AUC 0.85 and 0.71) in both cohorts when compared with each biomarker alone and PT-E (PCA3 and TMPRSS2-ERG). A GAPT-E score for high grade prostate cancer would avoid 92.1% of unnecessary prostate biopsies, compared to 61.9% when a PT-E score is used.

CONCLUSIONS

Urine extracellular vesicle GATA2 mRNA analysis improves the detection of high risk prostate cancer and may reduce the number of unnecessary biopsies.

BjuWRR1, a CC-NB-LRR gene identified in Brassica juncea, confers resistance to white rust caused by Albugo candida

BjuWRR1, a CNL-type R gene, was identified from an east European gene pool line of Brassica juncea and validated for conferring resistance to white rust by genetic transformation. White rust caused by the oomycete pathogen Albugo candida is a significant disease of crucifer crops including Brassica juncea (mustard), a major oilseed crop of the Indian subcontinent. Earlier, a resistance-conferring locus named AcB1-A5.1 was mapped in an east European gene pool line of B. juncea-Donskaja-IV. This line was tested along with some other lines of B. juncea (AABB), B. rapa (AA) and B. nigra (BB) for resistance to six isolates of A. candida collected from different mustard growing regions of India. Donskaja-IV was found to be completely resistant to all the tested isolates. Sequencing of a BAC spanning the locus AcB1-A5.1 showed the presence of a single CC-NB-LRR protein encoding R gene. The genomic sequence of the putative R gene with its native promoter and terminator was used for the genetic transformation of a susceptible Indian gene pool line Varuna and was found to confer complete resistance to all the isolates. This is the first white rust resistance-conferring gene described from Brassica species and has been named BjuWRR1. Allelic variants of the gene in B. juncea germplasm and orthologues in the Brassicaceae genomes were studied to understand the evolutionary dynamics of the BjuWRR1 gene.

Randomized trial to assess safety and clinical efficacy of intensive blood pressure reduction in acute spontaneous intracerebral haemorrhage

BACKGROUND

Haematoma expansion due to raised blood pressure in spontaneous intracerebral haemorrhage may determine outcome. The aim of this study was to determine safety and efficacy of lowering blood pressure in acute spontaneous intracerebral haemorrhage.

METHODS

This open label, multicentric trial randomized patients ≥18 years with spontaneous intracerebral haemorrhage with no secondary cause within 72 h of onset to tight BP control arm where treatment was initiated if mean arterial pressure (MAP) was ≥115 mm of Hg and conventional BP control arm where treatment was initiated if MAP was ≥130 mm of Hg. The MAP was maintained in the respective arm for another 72 h after which both arms had MAP below 115 mm of Hg. Primary outcome was modified Rankin Scale at 90 days.

RESULTS

118 patients, 59 in each arm were included. Follow up was available for all. Baseline characteristics were similar. At 90 days there was no significant difference between median mRS between the two arms. Odds Ratio for "poor outcome" (mRS 3-6) in the tight control arm (safety of the intervention) against "good outcome" (mRS 0-2) was not significant (OR 0.70 [95% CI 0.34-1.47] p = 0.35). Efficacy of the intervention in the form of Odds Ratio for "good outcome" in the tight control arm was not significant (OR 1.43 [95% CI 0.68-2.99], p = 0.35).

CONCLUSION

In patients with spontaneous intracerebral haemorrhage who present within 72 h of the onset of symptoms, MAP can be safely lowered if it crosses 115 mm of Hg but it does not improve clinical outcome.

Prostate biopsies: Available technique, approaches and diagnostic accuracy

Despite advances in the diagnosis of prostate cancer over the past century, it remains a leading cause of cancer related death. A recent recommendation against screening has further complicated the diagnosis and management of this condition. It remains to be demonstrated if newer diagnostic modalities will have an impact on mortality rates. Most certainly, not all prostate cancers need to be diagnosed, and methods of accurately diagnosing those cancers that lead to death needs more work. In this review article, we describe the different techniques, approaches and diagnostic accuracies of the currently used biopsy methods.

Comparison of histopathology and PCR based assay for detection of experimentally induced toxoplasmosis in murine model

OBJECTIVE

To compare histopathology and PCR based detection in diagnosis of experimentally induced toxoplasmosis of RH human strain of the parasite in murine models.

METHODS

A comparison of histopathology and PCR based detection was done to diagnose experimentally induced toxoplasmosis in ten inbred swiss albino mice after intraperitoneal inoculation of 100 tachyzoites of laboratory mantained human RH strain of the parasite. Tissue samples from lung, liver, spleen, brain, heart and kidney were taken and processed for histopathological examination while all the samples also were subjected to PCR, using primers directed to the multicopy of SAG 3 gene, in dublicates.

RESULTS

Histopathology revealed presence of tachyzoites only in liver while along with lung, liver, spleen and brain tissue yielded desired positive PCR amplicons.

CONCLUSIONS

The SAG 3 based PCR is able to diagnose toxoplasmosis in those tissues which are declared negative by histopathological assay.

Pathobiology of human RH strain induced experimental toxoplasmosis in murine model

Of late, toxoplasmosis has gained immense importance as an opportunist parasite in immunocompromised patients. In immunocompromised subjects, the disease is supposed to occur in acute form and causes acute toxoplasmic encephalitis. However, the exact pathogenesis of other vital organs, particularly in acute form of infection, is still a matter of debate. Therefore, an attempt was made to study the pathogenesis of acute form of toxoplasmosis using cryopreserved human RH strain of the parasite in murine models. For this, 100 tachyzoites were given to individual mice and upon the setup of acute form of infection, the mice were euthanized and the organs were processed for histopathology. Histopathology revealed tachyzoites in liver only while severe necrosis due to multiplication of tachyzoites were visible in liver, spleen, lungs and brain. Kidneys and heart appeared more or less normal. Finally, the pathology of disease in these organs is described in detail. The present research has generated some vital information regarding necrotic changes in tissues due to acute toxoplasmosis and will defiantly help the researchers in the better understanding of disease particularly in humans and putting up of suitable treatment regime for human subjects infected with acute toxoplasmosis.

In vitro inhibition activity of essential oils from some Lamiaceae species against phytopathogenic fungi

Natural products have been in focus as alternative, effective and safe materials against the phytopathogens. Investigations show Nepeta oils as effective in controlling the food crops decay. The inhibitory effects of essential oils derived from Nepeta leucophylla, Nepeta ciliaris, Nepeta clarkei and Calamintha umbrosa against five phytopthogenic fungi have been determined. In vitro antifungal activity varied with their constituents and target species. More active being the oils containing oxygenated terpenoids. Helminthosporium maydis was sensitive to the all oils, IC50 values have 43.6-109.3 μg mL(-1). The N. leucophylla oil possessing oxygenated iridoids was more effective against H. maydis (IC50 value of 43.6 μg mL(-1)) while N. ciliaris was more active against Fusarium oxysporum (IC50 value of 219.2 μg mL(-1)). The oils were effective against the spore germination of all the tested plant pathogens.

Type III TGF-β receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma

Growth factors and their receptors coordinate neuronal differentiation during development, yet their roles in the pediatric tumor neuroblastoma remain unclear. Comparison of mRNA from benign neuroblastic tumors and neuroblastomas revealed that expression of the type III TGF-β receptor (TGFBR3) decreases with advancing stage of neuroblastoma and this loss correlates with a poorer prognosis. Patients with MYCN oncogene amplification and low TGFBR3 expression were more likely to have an adverse outcome. In vitro, TβRIII expression was epigenetically suppressed by MYCN-mediated recruitment of histone deacetylases to regions of the TGFBR3 promoter. TβRIII bound FGF2 and exogenous FGFR1, which promoted neuronal differentiation of neuroblastoma cells. TβRIII and FGF2 cooperated to induce expression of the transcription factor inhibitor of DNA binding 1 via Erk MAPK. TβRIII-mediated neuronal differentiation suppressed cell proliferation in vitro as well as tumor growth and metastasis in vivo. These studies characterize a coreceptor function for TβRIII in FGF2-mediated neuronal differentiation, while identifying potential therapeutic targets and clinical biomarkers for neuroblastoma.

Reliability of motor parameters for follow-up after local steroid injection in carpal tunnel syndrome

BACKGROUND

Local steroid injection is one of the treatment modalities for carpal tunnel syndrome (CTS). Symptomatic and electrophysiological improvement has been previously documented. The electrophysiological parameter, which represents the most consistent change after local steroid injection, is not well-known.

OBJECTIVE

The objective of this study was to evaluate the changes in electrophysiological parameters 1 month after local steroid injection and to determine the parameter that is able to depict improvement across the severity spectrum of CTS.

MATERIALS AND METHODS

Forty-seven patients (27 with bilateral disease, 74 hands totally) were included. The electrophysiological parameters studied at baseline included sensory onset latency, sensory nerve action potential amplitude, sensory conduction velocity (CV), distal motor latency, compound muscle action potential amplitude and motor CV. All patients were injected with 40 mg triamcinalone at the wrist. After 1 month, symptomatic improvement from baseline was documented using visual analog score of 100. Electrophysiology was repeated. Paired t tests were done between baseline electrophysiology parameters and those obtained 1 month after steroid injection for significant improvement. Subgroup analyses were performed in hands with mild to moderate (Grade 3 or less by Bland's classification) and severe disease (Grades 4 and 5).

RESULTS

All patients showed a symptomatic improvement. Distal motor latency showed most consistent improvement irrespective of the severity of CTS. In mild to moderate CTS (Grade 3 or less of the classification given by Bland) sensory parameters were recordable and showed significant improvement in addition to distal motor latency. In the subcategory of severe CTS (Grades 4 and 5 of Bland) where sensory parameters are not recordable distal motor latency and the motor CV showed a significant improvement.

CONCLUSION

One month after local steroid injection among the electrophysiological parameters studied distal motor latencies showed most consistent and recordable improvement across the severity spectrum of CTS. This can be used as a single objective parameter to follow-up patients after a local steroid injection to document improvement or relapse. They can also be considered as objective parameter to follow-up patients after surgery.

Resveratrol worsens survival in SCID mice with prostate cancer xenografts in a cell-line specific manner, through paradoxical effects on oncogenic pathways

BACKGROUND

Resveratrol increases lifespan and decreases the risk of many cancers. We hypothesized resveratrol will slow the growth of human prostate cancer xenografts.

METHODS

SCID mice were fed Western diet (40% fat, 44% carbohydrate, 16% protein by kcal). One week later, human prostate cancer cells, either LAPC-4 (151 mice) or LNCaP (94 mice) were injected subcutaneously. Three weeks after injection, LAPC-4 mice were randomized to Western diet (control group), Western diet plus resveratrol 50 mg/kg/day, or Western diet plus resveratrol 100 mg/kg/day. The LNCaP mice were randomized to Western diet or Western diet plus resveratrol 50 mg/kg/day. Mice were sacrificed when tumors reached 1,000 mm(3). Survival differences among groups were assessed using Cox proportional hazards. Serum insulin and IGF axis were assessed using ELISAs. Gene expression was analyzed using Affymetrix gene arrays.

RESULTS

Compared to control in the LAPC-4 study, resveratrol was associated with decreased survival (50 mg/kg/day--HR 1.53, P = 0.04; 100 mg/kg/day--HR 1.22, P = 0.32). In the LNCaP study, resveratrol did not change survival (HR 0.77, P = 0.22). In combined analysis of both resveratrol 50 mg/kg/day groups, IGF-1 was decreased (P = 0.05) and IGFBP-2 was increased (P = 0.01). Resveratrol induced different patterns of gene expression changes in each xenograft model, with upregulation of oncogenic pathways E2F3 and beta-catenin in LAPC-4 tumors.

CONCLUSION

Resveratrol was associated with significantly worse survival with LAPC-4 tumors, but unchanged survival with LNCaP. Based on these preliminary data that resveratrol may be harmful, caution should be advised in using resveratrol for patients until further studies can be conducted.

Abstract 5041: The type III TGF-beta receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma

Growth factors and their receptors coordinate neuronal differentiation during development, yet their roles in the pediatric tumor neuroblastoma remain unclear. Here we report that expression of type III TGF-beta receptor (TβRIII) mRNA and protein decreases with advancing stage of neuroblastoma and positively correlates with prognosis. TβRIII expression is epigenetically suppressed by MYCN oncogene amplification and TβRIII expression can be used as a prognostic marker in neuroblastoma patients with MYCN amplification. TβRIII expression in neuroblastoma cells promotes neuronal differentiation and enhances the differentiating effects of FGF2 treatment. Mechanistically, glycosaminoglycan modifications on TβRIII bind FGF2 and FGFR1 to promote neuronal differentiation via Erk MAPK and the transcription factor ID1. TβRIII-mediated differentiation suppresses tumor cell proliferation in vitro and in vivo. These studies characterize a novel co-receptor function for TβRIII in FGF2-mediated neuronal differentiation of neuroblastoma cells, while identifying potential therapeutic targets and clinical biomarkers for advanced-stage disease. More generally, our results suggest that the targeting of growth factor receptors and downstream signaling pathways may prove useful in promoting neuronal differentiation to suppress neuroblastoma tumor growth.

Citation Format: Erik H. Knelson, Angela L. Gaviglio, Alok K. Tewari, Michael B. Armstrong, Andrew B. Nixon, Mark D. Starr, Karthikeyan Mythreye, Gerard C. Blobe. The type III TGF-beta receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma. [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 5041. doi:10.1158/1538-7445.AM2013-5041

Molecular cloning, sequencing, and biological characterization of GRA4 gene of Toxoplasma gondii

In the present study, GRA4 (dense granule antigen) gene of Toxoplasma gondii was cloned, sequenced, and biologically characterized. The nucleotide sequence data obtained were analyzed and submitted in GenBank database (accession no. EU660037). Analysis of nucleotide sequence of GRA4 gene revealed 99.2 % homology with the published sequence (accession no. M76432). The gene segment (open reading frame) of 1,054 bp was further amplified and re-cloned in expression vector pET-32a. The recombinant protein obtained following the expression in prokaryotic system had a molecular mass of approx. 50 kDa and showed good immunoreactivity with T. gondii sera collected from infected goats. The immunization study of the recombinant protein performed in laboratory mice and live challenge with T. gondii revealed a high level of IgG response against the tachyzoite lysate antigen (TLA) by an indirect ELISA. Protection against T. gondii challenge infection was not evident in immunized mice except for the prolongation of survival period by 2 days. Humoral immune response profile revealed initially a high level of IgG antibody, but at 1 week post-challenge, a sudden drop in the level of the antibody was appreciable. Cytokine profiling by enzyme-linked immunosorbent spot method revealed relatively high level of IFN-γ production by the rodent spleen cells followed by IL-10 and IL-4. Increase in IFN-γ production by spleen cells of immunized mice following TLA stimulation suggested direct correlation to the up-regulated Th1 cells. However, the present immunization trial failed to show any positive relationship with the protection of mice following T. gondii challenge infection.

Botulinum toxin for meralgia paresthetica in type 2 diabetes

Botulinum toxin has been used for a variety of neuropathic conditions in diabetes mellitus. Meralgia paresthetica is a mononeuropathy of femoral nerve seen in diabetes and obesity with an unclear etiopathogenesis. We studied the role of botulinum toxin in resistant cases of meralgia paresthetica in type 2 diabetes.

Babesia bigemina infection in yak (Poephagus grunniens L.): molecular detection and characterization

Yaks contribute significantly in the Himalayan high land economy. Specific information on prevalence of babesiosis in yaks is lacking. A fast and reliable PCR assay targeting Babesia bigemina small subunit ribosomal RNA sequence (SS rRNA) was laboratory standardized for molecular detection of B. bigemina in yaks. Restriction digestion of the PCR amplified 675 bp target sequence with Vsp I confirmed the prevalent species of Babesia as B. bigemina. Nucleotide sequencing and phylogenetic analysis of PCR amplified 675 bp SS rRNA sequence revealed a close genetic relationship with other bovine isolates of B. bigemina. A PCR based survey involving 94 blood samples of yak from the National Research Centre on Yak, Dirang, Arunachal Pradesh detected infection in 5.32% of yak blood samples, which was significantly higher in comparison to microscope based detection of infection in 2.13% blood smears. This is the first report on sensitive PCR based detection of B. bigemina infection in yaks and PCR-RFLP and nucleotide sequence analysis based molecular characterization of the B. bigemina isolated from yaks.

The trifecta outcome in 300 consecutive cases of robotic-assisted laparoscopic radical prostatectomy according to D'Amico risk criteria

BACKGROUND

To analyze the trifecta outcome (continence, potency, and cancer control) in 300 cases of robotic-assisted laparoscopic radical prostatectomy (RARP).

METHODS

A prospective assessment of outcomes in 300 consecutive patients that underwent a RARP performed by a single surgeon. Patients were grouped according to D'Amico risk criteria: Group I consisted of 'low-risk' cases (n = 64), Group II consisted of 'intermediate-risk' cases (n = 88), and Group III consisted of 'high-risk' cases (n = 148). Patients were evaluated for perioperative complications and the trifecta outcome.

RESULTS

The operation time, blood loss, post-operative stay, duration of urethral catheterization, and perioperative complication rate were similar among all groups. The incidence of bilateral neurovascular bundle (NVB) preservation was significantly decreased with the increasing risk of cases (P < 0.001). The continence rates at the 1-week, 1-month, 3-month, 6-month, and 12-month follow-ups did not differ significantly between groups. The potency rates at the 12-month follow-up were not significantly different. The positive surgical margin and positive lymph node metastasis rate increased with the increasing risk of cases (P < 0.001). The biochemical recurrence rate (BCR, PSA >0.2 ng/mL) was 3.1, 11.36, and 19.59% in Groups I, II and III, respectively (P = 0.004). The trifecta outcome for RARP with bilateral NVB preservation showed no significant differences among groups.

CONCLUSIONS

Undergoing a RARP is safe and feasible in high-risk prostate cancer patients. Compared to low-risk and intermediate-risk groups, the high-risk group had a significant higher incidence of positive surgical margin, positive lymph node metastasis, and BCR rate.

Chromatin accessibility reveals insights into androgen receptor activation and transcriptional specificity

BACKGROUND

Epigenetic mechanisms such as chromatin accessibility impact transcription factor binding to DNA and transcriptional specificity. The androgen receptor (AR), a master regulator of the male phenotype and prostate cancer pathogenesis, acts primarily through ligand-activated transcription of target genes. Although several determinants of AR transcriptional specificity have been elucidated, our understanding of the interplay between chromatin accessibility and AR function remains incomplete.

RESULTS

We used deep sequencing to assess chromatin structure via DNase I hypersensitivity and mRNA abundance, and paired these datasets with three independent AR ChIP-seq datasets. Our analysis revealed qualitative and quantitative differences in chromatin accessibility that corresponded to both AR binding and an enrichment of motifs for potential collaborating factors, one of which was identified as SP1. These quantitative differences were significantly associated with AR-regulated mRNA transcription across the genome. Base-pair resolution of the DNase I cleavage profile revealed three distinct footprinting patterns associated with the AR-DNA interaction, suggesting multiple modes of AR interaction with the genome.

CONCLUSIONS

In contrast with other DNA-binding factors, AR binding to the genome does not only target regions that are accessible to DNase I cleavage prior to hormone induction. AR binding is invariably associated with an increase in chromatin accessibility and, consequently, changes in gene expression. Furthermore, we present the first in vivo evidence that a significant fraction of AR binds only to half of the full AR DNA motif. These findings indicate a dynamic quantitative relationship between chromatin structure and AR-DNA binding that impacts AR transcriptional specificity.

Abstract 2923: Androgen receptor activation changes chromatin structure and transcriptional activation

Epigenetic mechanisms such as chromatin accessibility and histone modifications impact transcription factor binding to DNA and transcriptional specificity. The androgen receptor (AR), a master regulator of prostate cancer initiation and progression, acts primarily through ligand-activated transcription of target genes. By combining deep sequencing with DNase I hypersensitivity analysis (DNase-seq) and RNA analysis (RNA-seq) we assessed genome-wide chromatin structure and transcription and combined this data with publicly available AR chromatin immunoprecipitation data (AR Chip-seq). We find that 64% of DNase I hypersensitive sites (DHS) overlap each other before and after androgen in LNCaP cells. Interestingly, in regions with increased chromatin accessibility following androgen induction, the canonical AR DNA recognition motif is enriched. Comparing identified DHS to AR binding sites from three different data sets consistently reveals that 50% of AR binding overlaps a DHS in induced cells. Of those sites with both DHS and AR binding, approximately half are available prior to androgen induction (i.e. “primed”) and half open in response to androgen stimulation. This contrasts with the glucocorticoid receptor (GR), which was recently reported to bind to DNA primarily in regions that are accessible to nuclease cleavage prior to ligand activation. Our RNA-seq analysis discovered 367 genes regulated by AR activation (FDR &lt; 0.05), including 16 of the 19 most commonly identified AR-mediated genes in several other studies. Importantly, we find that regions of increased chromatin accessibility are significantly associated with genes identified as AR-regulated by RNA-seq. Finally, base pair resolution of the DNase-seq signal reveals distinct footprinting patterns associated with the AR-DNA interaction. Analysis of chromatin structure, AR binding, and transcription prior to and following androgen induction demonstrates that AR activation by ligand induces genome-wide changes in chromatin accessibility, these changes correspond to AR binding to the genome, and they impact AR-mediated transcriptional response. These findings suggest that interaction between the AR and DNA alters chromatin structure and transcriptional specificity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2923. doi:1538-7445.AM2012-2923

An animal model of MYC-driven medulloblastoma

Medulloblastoma (MB) is the most common malignant brain tumor in children. Patients whose tumors exhibit overexpression or amplification of the MYC oncogene (c-MYC) usually have an extremely poor prognosis, but there are no animal models of this subtype of the disease. Here, we show that cerebellar stem cells expressing Myc and mutant Trp53 (p53) generate aggressive tumors following orthotopic transplantation. These tumors consist of large, pleiomorphic cells and resemble human MYC-driven MB at a molecular level. Notably, antagonists of PI3K/mTOR signaling, but not Hedgehog signaling, inhibit growth of tumor cells. These findings suggest that cerebellar stem cells can give rise to MYC-driven MB and identify a novel model that can be used to test therapies for this devastating disease.

Learning curve for robotic assisted laparoscopic prostatectomy: a multi-institutional study of 3794 patients

AIM

The aim of this study was to define the learning curve for positive surgical margin (PSM) rate and operative time (OT) for robotic assisted laparoscopic radical prostatectomy (RALP); while the learning curve appears shorter for surgical safety for RALP compared to other surgical modalities, this has not been well established for the above parameters.

METHODS

We performed a retrospective cohort study of 3794 patients who underwent RALP between Jan 2003 and Sep 2009 by three surgeons (DL, PW, AKT) from three centers (UPenn, Karolinska, Cornell). Mean overall PSM rates and mean overall OT were calculated for all three surgeons at intervals of 50 RALPs per surgeon, and learning curves for these means were fit using a loess method. R version 2.71 was used for all statistical analysis.

RESULTS

The learning curve for PSM rates for all patients demonstrated improvements continued with increasing surgeon experience, with over 1600 cases required to get a PSM rate <10%. When pT3 patients were evaluated, the learning curve started to plateau after 1000-1500 cases. Mean OT plateaued after 750 cases though with further surgical experience the OTs started to climb again.

CONCLUSION

The learning curve for RALP is not as short as previously thought, and a large number of cases are needed to get PSM rates and OTs to a minimum. This suggests that RALP should be performed by high volume surgeons in order to optimize patient outcomes.

Control of poultry coccidiosis: changing trends

Coccidiosis is the most important protozoan disease affecting the poultry industry worldwide. Control of poultry coccidiosis is presently based on managerial skills and the use of prophylactic coccidiostatic drugs. With the emergence of drug resistant Eimeria strains, emphasis has been laid on development and use of safer vaccines; some of them have been commercialized successfully. The present review deals with the various factors responsible for the development of clinical coccidiosis in poultry as well as an overview of the currently available inducers and boosters of immunity against coccidiosis. There are three groups of vaccines currently available against coccidiosis which can be distinguished on the basis of characteristics of the Eimeria species included in the respective products, viz. vaccines based on live virulent strains, vaccines based on live attenuated strains, and vaccines based on live strains that are relatively tolerant to the ionophore compounds. The latter vaccine combines the early chemotherapeutic effect of ionophores with the late prophylactic effect of vaccination. Although in the near future more varieties of oocyst based live vaccines are expected, identification of selective coccidian-specific immunoprotective molecules is likely to get more attention to facilitate the sustainable control of poultry coccidiosis.

Haemoprotozoa of cattle in Northern Kerala, India

A cross-sectional study was conducted using 150 blood samples collected from apparently normal / healthy crossbred cattle of Northern Kerala, South India, for detection of haemoprotozoan infections using staining techniques (Giemsa and Acridine Orange) and specific PCR. Theileria like piroplasms and Babesia bigemina were the only protozoan organisms detected in blood smears. Polymerase chain reaction using specific primers revealed amplification of products specific for Trypanosoma evansi (34.6%), Theileria sp. other than T. annulata (16%) and B. bigemina (0.6%). The higher prevalence rate of Trypanosoma evansi indicated that the subclinical parasitism can be due to higher prevalence of tabanid flies. The study also revealed the presence of a theilerial piroplasm other than T. annulata in North Kerala, which needs further investigation.

Nerve-sparing radical prostatectomy: current concepts in a robotic era

Recovery of potency sufficient for penetrative intercourse at a year after surgery varies widely. Much of the progress achieved in the past two decades in improving potency outcomes after radical prostatectomy has resulted from an improved appreciation of the anatomic basis of the nerves responsible for erection. Recent studies suggest alternative and more complex course of nerves than previously described. Better appreciation of the variable and often invisible anatomical course of the cavernosal nerves continues to engender innovations in surgical technique to optimize their preservation. Exciting frontiers of research that include efforts in stem cell neural regeneration, development of specific fluorophores and biomarkers, and performing radical prostatectomy under hypothermic conditions may provide much-needed breakthroughs to improving potency outcomes following radical prostatectomy in this current age of improved life expectancy and heightened patient expectations.

Abstract B44: Chromatin structure impacts androgen receptor transcriptional specificity in prostate cancer cell lines

Androgen receptor (AR) regulated gene expression and the phenotypic impact of AR activity varies significantly between different prostate cancer (PC) models. Specifically, in genetically engineered prostate epithelial cells, AR activation causes slowed growth and differentiation whereas in patient-derived AR-positive prostate cancer cell lines, AR activity increases proliferation. While the factors modulating AR transcriptional specificity remain poorly understood, recent reports have underscored AR co-regulators and AR-dependent enhancer sequences as modulators of AR activity. We hypothesized that differences in chromatin structure may also contribute significantly to AR transcriptional specificity and phenotypic effect.

We used genome-wide DNase I hypersensitivity (HS) analysis coupled with tiled microarrays (DNase-chip) and ultra-high throughput sequencing (DNase-seq) to identify regions of open chromatin that are markers for various gene regulatory elements. DNaseI HS analysis was conducted in both LNCaP cells, which increase their proliferation in response to androgen, and LHSR-AR cells, a genetically engineered prostate epithelial cell line that differentiates in response to androgen. Each cell line was processed using our established DNaseI HS protocol prior to and after androgen stimulation. For DNase-chip, hypersensitive sites were identified using a custom microarray that included proximal promoter and adjacent regions of the top 100 genes differentially regulated by AR activation in each cell line. DNase-seq analysis was conducted on the entire genome of each cell line. Parzen scores based upon the frequency of detected genomic sequence were generated and used as a relative measure of DNA accessibility.

Our results demonstrate significant differences in chromatin structure between our two androgen-responsive models. DNase-chip analysis of specific genes such as KLK3 displays both overlapping and cell-type specific regions of chromatin availability that correlate with AR-regulated expression. KLK3 is differentially transcribed only in LNCaP, not LHSR-AR, in response to stimulation. Accordingly, a HS site matching a known AR enhancer element is found four kilobases upstream of the KLK3 TSS in LNCaP, but not in LHSR-AR. While chromatin structure explains some of the differences between these cell lines, it is not sufficient to account for all the differences observed. DNase-seq analysis in LNCaP cells suggests that there little immediate impact of AR activity on chromatin structure (approximately 77% of peaks are shared between stimulated and un-stimulated samples). In the proximal promoter regions of AR-regulated genes, the Parzen score increases in response to stimulation (Wilcoxon p &lt; 0.001), but the degree of change is relatively modest and may not be biologically significant. In addition, the number of peaks within the 100kb surrounding the TSS of AR-regulated genes did not change with androgen stimulation (604 un-stimulated, 613 stimulated, 75% in common). Finally, we examined the overlap between HS peaks and previously published putative AR binding sites. Of 279 suspected binding sites on chromosomes 19–22, none corresponded to a HS peak in unstimulated LNCaP cells, but 147 overlapped a HS peak in stimulated LNCaP cells. Overall, our LNCaP DNase-seq data suggests that the promoter regions of AR-regulated genes are primed for transcription, but that AR activation causes key alterations to the distal chromatin landscape. Further work is required to understand the mechanism behind phenotype-specific differences in the chromatin landscape and its effects on AR transcriptional specificity.

Citation Information: Cancer Res 2009;69(23 Suppl):B44.

The effects of varying dietary carbohydrate and fat content on survival in a murine LNCaP prostate cancer xenograft model

PURPOSE

Numerous dietary factors elevate serum levels of insulin and insulin-like growth factor I (IGF-I), both potent prostate cancer mitogens. We tested whether varying dietary carbohydrate and fat, without energy restriction relative to comparison diets, would slow tumor growth and reduce serum insulin, IGF-I, and other molecular mediators of prostate cancer in a xenograft model.

EXPERIMENTAL DESIGN

Individually caged male severe combined immunodeficient mice (n = 130) were randomly assigned to one of three diets (described as percent total calories): very high-fat/no-carbohydrate ketogenic diet (NCKD: 83% fat, 0% carbohydrate, 17% protein), low-fat/high-carbohydrate diet (LFD: 12% fat, 71% carbohydrate, 17% protein), or high-fat/moderate-carbohydrate diet (MCD: 40% fat, 43% carbohydrate, 17% protein). Mice were fed to maintain similar average body weights among groups. Following a preliminary feeding period, mice were injected with 1 x 10(6) LNCaP cells (day 0) and sacrificed when tumors were >or=1,000 mm(3).

RESULTS

Two days before tumor injection, median NCKD body weight was 2.4 g (10%) and 2.1 g (8%) greater than the LFD and MCD groups, respectively (P < 0.0001). Diet was significantly associated with overall survival (log-rank P = 0.004). Relative to MCD, survival was significantly prolonged for the LFD (hazard ratio, 0.49; 95% confidence interval, 0.29-0.79; P = 0.004) and NCKD groups (hazard ratio, 0.59; 95% confidence interval, 0.37-0.93; P = 0.02). Median serum insulin, IGF-I, IGF-I/IGF binding protein-1 ratio, and IGF-I/IGF binding protein-3 ratio were significantly reduced in NCKD relative to MCD mice. Phospho-AKT/total AKT ratio and pathways associated with antiapoptosis, inflammation, insulin resistance, and obesity were also significantly reduced in NCKD relative to MCD tumors.

CONCLUSIONS

These results support further preclinical exploration of carbohydrate restriction in prostate cancer and possibly warrant pilot or feasibility testing in humans.

Genomic Strategy for Targeting Therapy in Castration-Resistant Prostate Cancer

Purpose

Despite treatments which lower circulating androgens, advanced prostate cancers often maintain androgen receptor (AR) signaling. The variable response to secondary hormonal manipulations in men with castrate-resistant prostate cancer (CRPC) creates a compelling need for strategies to individualize therapy based on the molecular features of each patient's tumor.

Methods

A transcription-based AR activity signature was developed from an androgen-sensitive prostate cancer cell (LNCaP) and tested on independent data sets of prostate cancer cell lines and human tumors to assess its precision and accuracy in detecting AR activity. The AR signature was applied to multiple sets of prostate specimens to determine how AR activity changes with hormone therapy and progression and oncogenic pathway analysis was used to identify biologic pathways correlating with AR activity.

Results

A robust AR signature accurately predicts AR activity in multiple prostate cancer cell lines, has minimal variation between replicate samples, and accurately reflects an individual's hormone status and intraprostatic dihydrotestosterone levels. The AR signature finds AR activity to be high in local, untreated prostate tumors and decreased in prostate tissue after neoadjuvant hormone therapy and in CRPC. Heterogeneity of AR activity exists along the spectrum of prostate cancer progression and decreasing predicted AR activity correlates with increasing predicted Src activity and sensitivity to dasatinib (Src-targeting kinase inhibitor).

Conclusion

A transcription-based AR signature can detect AR activity within individual prostate cancer specimens and has the potential to help individualize and improve care for patients with CRPC.

Prevalence of Cryptosporidium andersoni: a molecular epidemiological survey among cattle in India

Cryptosporidiosis is an important and established cause of calfhood morbidity in bovines. The present communication reports the prevalence of Cryptosporidium infection among juvenile and adult cattle (6-24 months old) in India based on examination of faecal samples collected from 350 animals across three different agro-climatic regions of the country and further confirmation by a two-step nested PCR assay targeting 18S ssu rRNA gene. A total of 45 samples were positive for Cryptosoridium species by nested PCR assay. The PCR products were subjected to restriction fragment length polymorphism (RFLP) analysis using SspI and VspI restriction enzymes for species differentiation. The results showed that the species involved in all the samples found positive was Cryptosporidium andersoni. The overall prevalence rate was 12.85%, with highest occurrence in the northern states (14.37%) of the country. The animals between age group of 6-12 months were mostly affected (21.67%) and the season wise prevalence of infection was more during the hot and humid monsoon season (20.16%). The results clearly demonstrated that C. andersoni is the major Cryptosporidium species affecting juvenile and adult cattle in three agro-climatically different geographical regions of India. This is the first report on prevalence of C. andersoni in bovines from India the confirmation of which is based on application of nested PCR and PCR-RFLP based molecular tools.

A case of hereditary protein S deficiency presenting with cerebral sinus venous thrombosis and deep vein thrombosis at high altitude

A 35-year-old healthy male with no history of any past medical illness developed severe headache, vomiting and drowsiness while at high altitude (4,572 m) in the eastern Himalayan ranges. He was evacuated to a tertiary-care hospital where he was diagnosed to have cerebral sinus venous thrombosis (CSVT) on magnetic resonance imaging, with deep vein thrombosis (DVT) of his right popliteo-femoral vein on color Doppler study. Investigation for thrombophilia revealed protein S (PS) deficiency in this patient. Family screening revealed low levels of PS in two elder brothers. One brother had a history of 'stroke in young' at the age of 20 years with the other being asymptomatic. This established the hereditary nature of PS deficiency. We are not aware of any previously published report on hereditary PS deficiency combined with CSVT and DVT occurring at high altitude. However, 1 case of protein C deficiency with CSVT has been reported previously.

Prevalence and molecular characterization of bovine Cryptosporidium isolates in India

A survey based on PCR assay of 18S SSU rRNA gene revealed a 30.2% infection with Cryptosporidium spp., out of 457 faecal samples collected from neonatal bovine calves across three different regions of India. The PCR-RFLP pattern of the gene in all the positive cases established the species as Cryptosporidium parvum. Highest prevalence was recorded in the monsoon months (37.3%) and in the calves showing acute diarrhoea (32.3%). The calves below 15 days of age were mostly affected (45.1%). The infection was more prevalent in the northern parts (35.4%) of the country than in the eastern or southern parts. Results indicated that C. parvum was the only species of Cryptosporidium prevalent in bovine calves in three different geographical regions of India.

Role of antibiosis in the biological control of spot blotch ( Cochliobolus sativus) of wheat by Chaetomium globosum

Chaetomium globosum Kunze, has been identified as a potential antagonist of Cochliobolus sativus (S. Ito & Kurib.) Deschler ex Dastur. (Syn = Drechslera sorokiniana). Production of antifungal compounds by Chaetomium globosum (Cg) and their role in suppression of spot blotch of wheat caused by this fungus under in vitro and in vivo has been evaluated. Interaction between Chaetomium globosum isolates and C. sativus showed mycoparasitism by isolates Cg 1 and Cg 6 whereas isolates Cg 2, Cg 3, Cg 4 and Cg 5 showed antibiosis. Syringe filtered culture extracts of Cg 2 completely inhibited mycelial growth of C. sativus in liquid broth. In vitro bioassays were undertaken by amending the medium with crude extracts and agar diffusion method in order to assess the fungistatic activity of crude extracts from culture filtrates of different isolates of Chaetomium globosum. Significant differences in antagonism between isolates were observed. Antifungal metabolite profiling, on TLC (Thin Layer Chromatography) plates identified 13 compounds in isolate Cg 2, 11 compounds in Cg 3 and 7 compounds in Cg 6. Isolate Cg 1 produced only two faint bands and Cg 5 produced two bands of the same Rf value but of higher intensity. The production of antifungal compounds by isolates was positively correlated with antagonism to C. sativus on seedlings in glasshouse studies. The results showed high antifungal metabolite production by isolate Cg 2, which also gave maximum bioefficacy under laboratory and glasshouse conditions.

Synthesis and anti-inflammatory activities of N4,N5-disubstituted-3-methyl- H-pyrazolo[3,4-c]pyridazines

The synthesis and anti-inflammatory activity of 4,5-dihydroxy-3-methyl-1H-pyrazolo[3,4-c]pyridazine (4), 4,5-dichloro-3-methyl-1H-pyrazolo[3,4-c]pyridazine (5), 4,-benzoyloxy-3-methyl-1-benzoyl-1H-pyrazolo[3,4-c]pyridazin-5yl benzoate (6), 3-methyl-N4,N5-bis(4-methylphenyl)-1H-pyrazolo[3,4-c]pyridazine-4,5-diamine (7), 4[[5-(4-carboxyanilino)-3-methyl-1H-pyrazolo[3,4-c]pyridazin-4yl]amino]benzoic acid (8), N-[5-(benzoylamino)-3-methyl-1H-pyrazolo[3,4-c]pyridazin-4-yl]benzamide (9) and 3-methyl-N4,N5-bis[4-(1H-benzimidazol-2yl)phenyl]-1H-pyrazolo[3,4-c]pyridazine-4,5-diamine (10) are being reported.

Comparison of indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) in detecting Babesia bigemina infection in cattle

An indirect immunofluorescence test (IIF) and an enzyme-linked immuno-sorbent assay (ELISA) were standardised to investigate the prevalence of bovine babesiosis caused by Babesia bigemina in experimentally and naturally infected bovids. Both IIF and ELISA detected antibodies to B. bigemina 7 days after experimental infection with 87.5% and 100% sensitivity, respectively. The IIF results indicated that a titre greater than 1:64 was a reliable indicator of B. bigemina infection. Serological study of 214 serum samples collected from Boophilus microplus infested cattle from the State of Orissa revealed 33.6% overall seroreactivity by ELISA, whereas IIF recorded 9.4%. Both IIF and ELISA showed some degree of cross-reactivity between Indian (Izatnagar) and Mexican strains of B. bigemina.