Micro-RNAs With Prognostic Significance in Gallbladder Cancer: A Systematic Review and Meta-Analysis.

Gallbladder cancer (GBC) stands out as one of the most widespread malignancies impacting the biliary tract globally. Despite increasing interest, to the best of our knowledge, no meta-analysis has been undertaken to amalgamate the existing data concerning the prognostic significance of micro-RNAs (miRNAs) in GBC in comparison to studies on miRNAs in other cancers. Hence, this systematic review and meta-analysis aimed at determining the prognostic significance of miRNAs in GBC patients. Comprehensive literature searches were conducted across PubMed, Cochrane Library, Ovid, Scopus, and Science Direct databases. Studies that evaluated the association between miRNAs and overall survival in GBC patients were included. Random-effect meta-analysis was employed to pool hazard ratios (HRs) and their 95% confidence intervals (CIs) across studies. A total of 15 studies, encompassing 16 miRs, were included for our analysis. The pooled analysis revealed that a high expression of miR-204, miR-7-2-3p, miR-29c-3p, miR-125b, miR-20a, miR-139-5p, miR-141, miR-92b-3p, miR-335, and miR-372 was significantly associated with poor prognosis and increased risk (HR>1 and the upper bound of the 95% CI>1). Additionally, these miRNAs were associated with the overall survival (HR = 1.56, 95% CI = 0.91-2.20, I2 = 91.82%). Significant heterogeneity was observed and could be attributed to the limited number of studies available on the GBC and significant reliance on quantitative real-time PCR for the detection of miRNAs. In conclusion, specific miRNAs exhibit prognostic significance in GBC, with potential implications for patient stratification and targeted therapeutic interventions. However, due to the heterogeneity among studies, these findings should be interpreted cautiously and validated in larger cohorts.

Evaluation of Deoxyribonucleic Acid Damage Using Neutral Comet Assay for High Radiation Doses: A Feasibility Study.

Purpose: This study aims to investigate the use of the neutral comet assay to assess deoxyribonucleic acid (DNA) damage in lymphocytes exposed to high doses of radiation. Materials and Methods: The research was conducted by obtaining informed consent, after which blood samples were taken from seven healthy individuals and this study was approved by the institutional ethics committee. At first, for the determination of dose-effect curves, samples obtained from the first five individuals were irradiated for doses ranging from 0 to 35 Gy after which they were processed under neutral comet assay. In order to verify the determined dose-effect curves, a test dose of 15 Gy was delivered to the samples obtained from the sixth and seventh individuals. The amount of DNA damage from the obtained comet assay images was analyzed using four comet assay parameters namely % tail DNA, tail length, tail moment (TM), and Olive TM (OTM). The most suitable comet assay parameter was evaluated based on the obtained dose-effect curves. Furthermore, the distribution of individual cells for each dose point was evaluated for all the four comet assay parameters to find the optimal parameter. Results: From our results, it was found that from 0 to 25 Gy all the four comet assay parameters fit well into a linear quadratic curve and above 25 Gy saturation was observed. Based on the individual cell distribution data, it was found that % tail DNA could be an optimal choice to evaluate DNA damage while using neutral comet assay for high-dose ionizing radiation. Conclusion: The neutral comet assay could be a potential tool to assess DNA damage from high doses of ionizing radiation greater than 5 Gy.

Leukotriene A4 hydrolase (LTA4H rs17525495) gene polymorphisms and paradoxical reactions in extrapulmonary tuberculosis.

Paradoxical reactions (PRs) are poorly studied complex immunological phenomena, among patients with tuberculosis (TB). When PRs involves critical structures like the central nervous system (CNS), immunomodulatory therapy is often required. Predictors for PRs in TB to pre-empt appropriate treatment strategies in high-risk groups are lacking. TT genotype of Leukotriene A4 hydrolase (LTA4H) promoter region rs17525495 polymorphisms are associated with exaggerated immune responses in Tuberculous meningitis (TBM), the most severe form of extrapulmonary tuberculosis (EPTB). The association of these polymorphisms with PRs is not known. We evaluated this plausibility among 113 patients with EPTB, at high risk of PRs. Majority [81 (71.7%)] had disseminated tuberculosis with prominent CNS [54 (47.8%)] and lymph node involvement [47 (41.6%)]. Human immunodeficiency Virus (HIV) co-infection was seen among 23 (20.3%) patients. PRs were noted in 38.9% patients, at a median duration of 3 months (IQR 2-4). LTA4H rs17525495 single nucleotide polymorphism (SNP) analysis showed 52 (46%) patients had CC, 43 (38.1%) had CT and 18 (15.9%) had TT genotypes. There was no statistically significant difference in occurrence [CC 38.5% vs CT 39.5% vs TT 38.7%] and time of onset [median (IQR)] of PRs across the genotypes [CC 3 (1-4.7), CT 3 (2-5), TT 2 (2-3)]. PRs was shown to be significantly linked with HIV co-infection (RR 0.6, 95% CI 0.29-1.28), culture positivity (RR 0.5, 95% CI 0.28-1.14), TB Lymphadenitis (RR 0.7, 95% CI 0.44-1.19) and CNS involvement RR 2.1, 95% CI 1.27-3.49) in the univariate analysis (p < 0.2). On multivariate analysis, CNS involvement alone was associated with PRs (aRR 3.8 (1.38-10.92); p < 0.01). PRs were associated with CNS involvement but not with LTA4H rs17525495 polymorphisms.

Association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms with vitamin B12 deficiency and adverse perinatal outcomes among pregnant women of rural South India - a cross sectional longitudinal study.

OBJECTIVES: To determine the occurrence of MTHFR gene polymorphisms and to study their association with vitamin B12 deficiency and adverse perinatal outcomes among a cohort of pregnant women from Kaniyambadi block, Tamil Nadu. METHODS: 120 consecutive pregnant women who were ≤20 weeks of gestational age from the 82 villages of Kaniyambadi block were recruited. Genomic DNA was isolated from the peripheral blood. PCR amplification was done followed by Sangers sequencing. Maternal and neonatal outcomes were extracted. Data was entered and analysed. RESULTS: Our study found the occurrence of c.1298A>C variant in homozygous state in 14.2% and c.677C>T heterozygous state in 15%. Sanger sequencing of exon 7 identified another pathogenic variant c.1262G>T in heterozygous state in two of them. Both the mothers who harboured that variant had preterm delivery and one of them gave birth to a low-birth-weight neonate. In the entire cohort, 5% of the mothers had abortion, 4.2% of them had preterm delivery and 8.8% of the neonates had low birth weight. Presence of c.1298A>C or c.677C>T variants were associated with vitamin B12 deficiency [Pearson Chi squared value (χ2)=7.9 and 7.6 respectively; p=0.02]. Heterozygous pathogenic variant c.1262G>T was associated with both adverse maternal [χ2=11.5; p=0.001] and neonatal [χ2=18.3; p=0.009] outcomes. CONCLUSIONS: MTHFR gene polymorphisms could be associated with several adverse perinatal outcomes and vitamin B12 deficiency. Further larger studies are needed to prove the pathogenicity of c.1262G>T variant on pregnancy.

Cryptogenic Stroke in the Young: Role of Candidate Gene Polymorphisms in Indian Patients with Ischemic Etiology.

CONTEXT: Strokes that remain without a definite cause even after an extensive workup, termed cryptogenic strokes, constitute up to 30-40% of ischemic strokes (ISs) in the young. Some of them can have a genetic basis. However, the well-established genetic causes account for only a small percentage of these cases. AIM: To evaluate the association of cryptogenic young IS with 16 candidate gene polymorphisms. SETTINGS AND DESIGN: A case-control study with cryptogenic young IS patients (South and North Indians; n = 105) and age, sex, and ethnicity-matched controls (n = 215). SUBJECTS AND METHODS: Genotyping was carried out by PCR-RFLP method using DNA extracted from the blood. STATISTICAL ANALYSIS USED: Association of the genotypes with the disease was studied using Chi-square test. RESULTS: MTHFR rs1801133 and KNG1 rs710446 showed significant statistical association with cryptogenic young IS (P = 0.0261 and 0.0157, respectively) in the Indian population. Significant association of KNG1 rs710446 (P 0.0036) and FXII rs1801020 (P 0.0376) with cryptogenic young stroke in South Indian males, SERPINC1 rs2227589 in South Indian female patients (P = 0.0374), and CYP4V2 rs13146272 in North Indian males (P = 0.0293) was observed. CONCLUSIONS: Our study indicates that in the Indian population MTHFR rs1801133, KNG rs710446, FXII rs1801020, SERPINC1 rs2227589, CYP4V2 rs13146272, and FXIII V34L may be significant risk factors for cryptogenic IS in the young. In addition, ethnicity and gender play a significant role. Further studies with larger sample size are required to completely establish these polymorphisms as risk factors for cryptogenic IS in young Indians.

Clinicoradiological Spectrum of L-2-Hydroxy Glutaric Aciduria: Typical and Atypical Findings in an Indian Cohort.

CONTEXT: Neurometabolic disorders form an important group of potentially treatable diseases. It is important to recognize the clinical phenotype and characteristic imaging patterns to make an early diagnosis and initiate appropriate treatment. L-2-hydroxy glutaric aciduria (L2HGA) is a rare organic aciduria with a consistent and highly characteristic imaging pattern, which clinches the diagnosis in most cases. AIMS: The study aims to describe the clinical profile, magnetic resonance imaging (MRI) patterns, and outcome in a cohort of children with L2HGA and to assess the clinicoradiological correlation. MATERIALS AND METHODS: This is a retrospective descriptive study done at the Department of Radiodiagnosis and Neurological Sciences of our institution. Clinical and radiological findings of children diagnosed with L2HGA over an 8-year period (2010-2017) were collected and analyzed. Descriptive statistical analysis of clinical and imaging data was performed. RESULTS: There were six girls and four boys. A total of 14 MRI brain studies in 10 patients with the diagnosis were analyzed. MRI of all patients showed a similar pattern with extensive confluent subcortical white-matter signal changes with symmetrical involvement of dentate nuclei and basal ganglia. In two children who presented with acute decompensation, there was asymmetric cortical involvement and restricted diffusion, which are previously unreported. There was no significant correlation between the radiological pattern with the disease duration, clinical features, or course of the disease. CONCLUSION: MRI findings in L2HGA are highly consistent and diagnostic, which helps in early diagnosis, particularly in resource-constraint settings, where detailed metabolic workup is not possible. The article also describes novel clinical radiological profile of acute encephalopathic clinical presentation.

Revisiting magnetic resonance imaging pattern of Krabbe disease - Lessons from an Indian cohort.

CONTEXT: Krabbe disease shows considerable heterogeneity in clinical features and disease progression. Imaging phenotypes are equally heterogeneous but show distinct age-based patterns. It is important for radiologists to be familiar with the imaging spectrum to substantially contribute toward early diagnosis, prognostication, and therapeutic decisions. AIMS: The study aims to describe different magnetic resonance imaging (MRI) patterns observed in a cohort of children with Krabbe disease and to assess correlation with age-based clinical phenotypes. MATERIALS AND METHODS: This is a retrospective descriptive study done at the Departments of Radiodiagnosis and Neurological Sciences of our institution, a tertiary care hospital in Southern India. Imaging features of children diagnosed with Krabbe disease over a 10-year period (2009-2018) were collected and analyzed. RESULTS: A total of 38 MRI brain studies from 27 patients were analyzed. Four distinct MRI patterns were recognizable among the different clinical subtypes. All patients from the early and late infantile group showed deep cerebral and cerebellar white matter and dentate hilum involvement. Optic nerve thickening was, however, more common in the former group. Adult-onset subtype showed isolated involvement of corticospinal tract, posterior periventricular white matter, and callosal splenium with the absence of other supra- and infra-tentorial findings. Juvenile subgroup showed heterogeneous mixed pattern with 78% showing adult subtype pattern and 22% showing patchy involvement of deep cerebral white matter with dentate hilum signal changes. CONCLUSION: Krabbe disease shows distinct imaging features which correspond to different clinical age-based subtypes. This article reemphasizes these distinct imaging phenotypes, highlights a novel imaging appearance in juvenile Krabbe, and also alludes to the rare variant of saposin deficiency. Awareness of these patterns is essential in suggesting the appropriate diagnosis and guiding conclusive diagnostic workup. Large multicenter longitudinal studies are needed to further define the role of imaging in predicting the clinical course and thus to guide therapeutic options.

Prothrombin G20210A polymorphism in patients with venous and cryptogenic arterial strokes among ethnic groups in south and north India.

Background: Prothrombin (PT) G20210A is one of the genetic polymorphisms associated with thrombophilia. Studies show a low prevalence for this polymorphism in Asian populations with only one subject reported from India. We studied the prevalence and association of this polymorphism in patients with arterial and venous strokes and their matched controls in south and north India. Methods: We recruited patients with cerebral venous thrombosis (mean age 37.2 years) and cryptogenic ischaemic stroke (mean age 36.7 years), and age- and sex-matched controls (mean age 37.6 years) from south and north India. Genotyping was carried out using polymerase chain reaction followed by restriction fragment length polymorphism, and the prevalence of the variants among the patients and controls was compared. Results: The heterozygous allele of the polymorphism was detected in both groups with significantly higher prevalence among north Indians (5/154; 3.2%) compared with south Indians (4/516; 0.8%; p = 0.026). Thrombosis as a manifestation of this polymorphism was more among north Indians with 4/82 (4.9%) of patients with ischaemic stroke and cerebral venous thrombosis having this polymorphism compared with south Indian patients 1/72 (1.4%), p = 0.003. Conclusion: PT G20210A is prevalent in India, especially among those from north India. Its role in predisposition to thrombosis needs to be studied further along with other known risk factors.

A Novel Quantitative Multiplex Tissue Immunoblotting for Biomarkers Predicts a Prostate Cancer Aggressive Phenotype.

BACKGROUND: Early prediction of disease progression in men with very low-risk (VLR) prostate cancer who selected active surveillance (AS) rather than immediate treatment could reduce morbidity associated with overtreatment. METHODS: We evaluated the association of six biomarkers [Periostin, (-5, -7) proPSA, CACNA1D, HER2/neu, EZH2, and Ki-67] with different Gleason scores and biochemical recurrence (BCR) on prostate cancer TMAs of 80 radical prostatectomy (RP) cases. Multiplex tissue immunoblotting (MTI) was used to assess these biomarkers in cancer and adjacent benign areas of 5 µm sections. Multivariate logistic regression (MLR) was applied to model our results. RESULTS: In the RP cases, CACNA1D, HER2/neu, and Periostin expression were significantly correlated with aggressive phenotype in cancer areas. An MLR model in the cancer area yielded a ROC-AUC = 0.98, whereas in cancer-adjacent benign areas, yielded a ROC-AUC = 0.94. CACNA1D and HER2/neu expression combined with Gleason score in a MLR model yielded a ROC-AUC = 0.79 for BCR prediction. In the small biopsies from an AS cohort of 61 VLR cases, an MLR model for prediction of progressors at diagnosis retained (-5, -7) proPSA and CACNA1D, yielding a ROC-AUC of 0.78, which was improved to 0.82 after adding tPSA into the model. CONCLUSIONS: The molecular profile of biomarkers is capable of accurately predicting aggressive prostate cancer on retrospective RP cases and identifying potential aggressive prostate cancer requiring immediate treatment on the AS diagnostic biopsy but limited in BCR prediction. IMPACT: Comprehensive profiling of biomarkers using MTI predicts prostate cancer aggressive phenotype in RP and AS biopsies.

Evaluation of two mitochondrial DNA biomarkers for prostate cancer detection.

BACKGROUND: A 3.4kb deletion (3.4kbΔ ) in mitochondrial DNA (mtDNA) found in histologically normal prostate biopsy specimens has been reported to be a biomarker for the increased probability of prostate cancer. Increased mtDNA copy number is also reported as associated with cancer. OBJECTIVE: Independent evaluation of these two potential prostate cancer biomarkers using formalin-fixed paraffin-embedded (FFPE) prostate tissue and matched urine and serum from a high risk cohort of men with and without prostate cancer. METHODS: Biomarker levels were detected via qPCR. RESULTS: Both 3.4kbΔ and mtDNA levels were significantly higher in cancer patient FFPE cores (p= 0.045 and p= 0.070 respectively at > 90% confidence). Urine from cancer patients contained significantly higher levels of mtDNA (p= 0.006, 64.3% sensitivity, 86.7% specificity). Combining the 3.4kbΔ and mtDNA gave better performance of detecting prostate cancer than either biomarker alone (FFPE 73.7% sensitivity, 65% specificity; urine 64.3% sensitivity, 100% specificity). In serum, there was no difference for any of the biomarkers. CONCLUSIONS: This is the first report on detecting the 3.4kbΔ in urine and evaluating mtDNA levels as a prostate cancer biomarker. A confirmation study with increased sample size and possibly with additional biomarkers would need to be conducted to corroborate and extend these observations.

Macrophage inhibitory cytokine 1 biomarker serum immunoassay in combination with PSA is a more specific diagnostic tool for detection of prostate cancer.

BACKGROUND: Prostate cancer (PCa) is the most common malignancy among men in the United States. Though highly sensitive, the often-used prostate-specific antigen (PSA) test has low specificity which leads to overdiagnosis and overtreatment of PCa. This paper presents results of a retrospective study that indicates that testing for macrophage inhibitory cytokine 1 (MIC-1) concentration along with the PSA assay could provide much improved specificity to the assay. METHODS: The MIC-1 serum level was determined by a novel p-Chip-based immunoassay run on 70 retrospective samples. The assay was configured on p-Chips, small integrated circuits (IC) capable of storing in their electronic memories a serial number to identify the molecular probe immobilized on its surface. The distribution of MIC-1 and pre-determined PSA concentrations were displayed in a 2D plot and the predictive power of the dual MIC-1/PSA assay was analyzed. RESULTS: MIC-1 concentration in serum was elevated in PCa patients (1.44 ng/ml) compared to normal and biopsy-negative individuals (0.93 ng/ml and 0.88 ng/ml, respectively). In addition, the MIC-1 level was correlated with the progression of PCa. The area under the receiver operator curve (AUC-ROC) was 0.81 providing an assay sensitivity of 83.3% and specificity of 60.7% by using a cutoff of 0.494 for the logistic regression value of MIC-1 and PSA. Another approach, by defining high-frequency PCa zones in a two-dimensional plot, resulted in assay sensitivity of 78.6% and specificity of 89.3%. CONCLUSIONS: The analysis based on correlation of MIC-1 and PSA concentrations in serum with the patient PCa status improved the specificity of PCa diagnosis without compromising the high sensitivity of the PSA test alone and has potential for PCa prognosis for patient therapy strategies.

Selective invocation of shape priors for deformable segmentation and morphologic classification of prostate cancer tissue microarrays.

Shape based active contours have emerged as a natural solution to overlap resolution. However, most of these shape-based methods are computationally expensive. There are instances in an image where no overlapping objects are present and applying these schemes results in significant computational overhead without any accompanying, additional benefit. In this paper we present a novel adaptive active contour scheme (AdACM) that combines boundary and region based energy terms with a shape prior in a multi level set formulation. To reduce the computational overhead, the shape prior term in the variational formulation is only invoked for those instances in the image where overlaps between objects are identified; these overlaps being identified via a contour concavity detection scheme. By not having to invoke all three terms (shape, boundary, region) for segmenting every object in the scene, the computational expense of the integrated active contour model is dramatically reduced, a particularly relevant consideration when multiple objects have to be segmented on very large histopathological images. The AdACM was employed for the task of segmenting nuclei on 80 prostate cancer tissue microarray images from 40 patient studies. Nuclear shape based, architectural and textural features extracted from these segmentations were extracted and found to able to discriminate different Gleason grade patterns with a classification accuracy of 86% via a quadratic discriminant analysis (QDA) classifier. On average the AdACM model provided 60% savings in computational times compared to a non-optimized hybrid active contour model involving a shape prior.

Nuclear morphometry, epigenetic changes, and clinical relevance in prostate cancer.

Nuclear structure alterations in cancer involve global genetic (mutations, amplifications, copy number variations, translocations, etc.) and epigenetic (DNA methylation and histone modifications) events that dramatically and dynamically spatially change chromatin, nuclear body, and chromosome organization. In prostate cancer (CaP) there appears to be early (<50 years) versus late (>60 years) onset clinically significant cancers, and we have yet to clearly understand the hereditary and somatic-based molecular pathways involved. We do know that once cancer is initiated, dedifferentiation of the prostate gland occurs with significant changes in nuclear structure driven by numerous genetic and epigenetic processes. This review focuses upon the nuclear architecture and epigenetic dynamics with potential translational clinically relevant applications to CaP. Further, the review correlates changes in the cancer-driven epigenetic process at the molecular level and correlates these alterations to nuclear morphological quantitative measurements. Finally, we address how we can best utilize this knowledge to improve the efficacy of personalized treatment of cancer.

EGFR-mediated Beclin 1 phosphorylation in autophagy suppression, tumor progression, and tumor chemoresistance.

Cell surface growth factor receptors couple environmental cues to the regulation of cytoplasmic homeostatic processes, including autophagy, and aberrant activation of such receptors is a common feature of human malignancies. Here, we defined the molecular basis by which the epidermal growth factor receptor (EGFR) tyrosine kinase regulates autophagy. Active EGFR binds the autophagy protein Beclin 1, leading to its multisite tyrosine phosphorylation, enhanced binding to inhibitors, and decreased Beclin 1-associated VPS34 kinase activity. EGFR tyrosine kinase inhibitor (TKI) therapy disrupts Beclin 1 tyrosine phosphorylation and binding to its inhibitors and restores autophagy in non-small-cell lung carcinoma (NSCLC) cells with a TKI-sensitive EGFR mutation. In NSCLC tumor xenografts, the expression of a tyrosine phosphomimetic Beclin 1 mutant leads to reduced autophagy, enhanced tumor growth, tumor dedifferentiation, and resistance to TKI therapy. Thus, oncogenic receptor tyrosine kinases directly regulate the core autophagy machinery, which may contribute to tumor progression and chemoresistance.

Acquisition of paclitaxel resistance is associated with a more aggressive and invasive phenotype in prostate cancer.

Drug resistance is a major limitation to the successful treatment of advanced prostate cancer (PCa). Patients who have metastatic, castration-resistant PCa (mCRPC) are treated with chemotherapeutics. However, these standard therapy modalities culminate in the development of resistance. We established paclitaxel resistance in a classic, androgen-insensitive mCRPC cell line (DU145) and, using a suite of molecular and biophysical methods, characterized the structural and functional changes in vitro and in vivo that are associated with the development of drug resistance. After acquiring paclitaxel-resistance, cells exhibited an abnormal nuclear morphology with extensive chromosomal content, an increase in stiffness, and faster cytoskeletal remodeling dynamics. Compared with the parental DU145, paclitaxel-resistant (DU145-TxR) cells became highly invasive and motile in vitro, exercised greater cell traction forces, and formed larger and rapidly growing tumors in mouse xenografts. Furthermore, DU145-TxR cells showed a discrete loss of keratins but a distinct gain of ZEB1, Vimentin and Snail, suggesting an epithelial-to-mesenchymal transition. These findings demonstrate, for the first time, that paclitaxel resistance in PCa is associated with a trans-differentiation of epithelial cell machinery that enables more aggressive and invasive phenotype and portend new strategies for developing novel biomarkers and effective treatment modalities for PCa patients.

Cell orientation entropy (COrE): predicting biochemical recurrence from prostate cancer tissue microarrays.

We introduce a novel feature descriptor to describe cancer cells called Cell Orientation Entropy (COrE). The main objective of this work is to employ COrE to quantitatively model disorder of cell/nuclear orientation within local neighborhoods and evaluate whether these measurements of directional disorder are correlated with biochemical recurrence (BCR) in prostate cancer (CaP) patients. COrE has a number of novel attributes that are unique to digital pathology image analysis. Firstly, it is the first rigorous attempt to quantitatively model cell/nuclear orientation. Secondly, it provides for modeling of local cell networks via construction of subgraphs. Thirdly, it allows for quantifying the disorder in local cell orientation via second order statistical features. We evaluated the ability of 39 COrE features to capture the characteristics of cell orientation in CaP tissue microarray (TMA) images in order to predict 10 year BCR in men with CaP following radical prostatectomy. Randomized 3-fold cross-validation via a random forest classifier evaluated on a combination of COrE and other nuclear features achieved an accuracy of 82.7 +/- 3.1% on a dataset of 19 BCR and 20 non-recurrence patients. Our results suggest that COrE features could be extended to characterize disease states in other histological cancer images in addition to prostate cancer.

Nuclear morphometry, nucleomics and prostate cancer progression.

Prostate cancer (PCa) results from a multistep process. This process includes initiation, which occurs through various aging events and multiple insults (such as chronic infection, inflammation and genetic instability through reactive oxygen species causing DNA double-strand breaks), followed by a multistep process of progression. These steps include several genetic and epigenetic alterations, as well as alterations to the chromatin structure, which occur in response to the carcinogenic stress-related events that sustain proliferative signaling. Events such as evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis are readily observed. In addition, in conjunction with these critical drivers of carcinogenesis, other factors related to the etiopathogenesis of PCa, involving energy metabolism and evasion of the immune surveillance system, appear to be involved. In addition, when cancer spread and metastasis occur, the 'tumor microenvironment' in the bone of PCa patients may provide a way to sustain dormancy or senescence and eventually establish a 'seed and soil' site where PCa proliferation and growth may occur over time. When PCa is initiated and progression ensues, significant alterations in nuclear size, shape and heterochromatin (DNA transcription) organization are found, and key nuclear transcriptional and structural proteins, as well as multiple nuclear bodies can lead to precancerous and malignant changes. These series of cellular and tissue-related malignancy-associated events can be quantified to assess disease progression and management.

Adaptive energy selective active contour with shape priors for nuclear segmentation and gleason grading of prostate cancer.

Shape based active contours have emerged as a natural solution to overlap resolution. However, most of these shape-based methods are computationally expensive. There are instances in an image where no overlapping objects are present and applying these schemes results in significant computational overhead without any accompanying, additional benefit. In this paper we present a novel adaptive active contour scheme (AdACM) that combines boundary and region based energy terms with a shape prior in a multi level set formulation. To reduce the computational overhead, the shape prior term in the variational formulation is only invoked for those instances in the image where overlaps between objects are identified; these overlaps being identified via a contour concavity detection scheme. By not having to invoke all 3 terms (shape, boundary, region) for segmenting every object in the scene, the computational expense of the integrated active contour model is dramatically reduced, a particularly relevant consideration when multiple objects have to be segmented on very large histopathological images. The AdACM was employed for the task of segmenting nuclei on 80 prostate cancer tissue microarray images. Morphological features extracted from these segmentations were found to able to discriminate different Gleason grade patterns with a classification accuracy of 84% via a Support Vector Machine classifier. On average the AdACM model provided 100% savings in computational times compared to a non-optimized hybrid AC model involving a shape prior.

Creatine kinase brain overexpression protects colorectal cells from various metabolic and non-metabolic stresses.

Creatine kinase brain (CKB) is one of three cytosolic isoforms of creatine kinase that is predominantly expressed in the brain. The enzyme is overexpressed in a wide variety of cancers, with the exception of colon cancer, where it is downregulated. The significance of this downregulation remains poorly understood. Here, we demonstrate that overexpression of CKB-C283S, a dominant-negative construct that lacks the kinase function but retains its ability to dimerize, causes remarkable changes in cell shape, adhesion, and invasion. Furthermore, it results in increased expression of stromal cell markers such as PAGE4 and SNAIL, suggesting an epithelial-to-mesenchymal transition (EMT) in these cells. In cells transfected with a CKB-expressing construct, CKB localizes not only to the cytosol but also to the nucleus, indicating a structural or kinase role unrelated to ATP storage. Furthermore, overexpression of CFP-tagged wild-type (WT) CKB in Caco-2 colon cancer cells dramatically increased the number of cells in G2/M but had little effect on cell proliferation. Taken together, these data demonstrate that the downregulation of CKB may play an important role in colon cancer progression by promoting EMT.