Retnagowri Rajandram

Differentiation of oncocytoma from chromophobe renal cell carcinoma (RCC): Can novel molecular biomarkers help solve an old problem?

Standard treatment of renal neoplasms remains surgical resection, and nephrectomy for localised renal cell carcinoma (RCC) still has the best chance of cure with excellent long-term results. For smaller renal masses, especially stage T1a tumours less than 4 cm, nephron-sparing surgery is often employed. However, small incidentally detected renal masses pose an important diagnostic dilemma as a proportion of them may be benign and could be managed conservatively. Renal oncocytoma is one such lesion that may pose little risk to a patient if managed with routine surveillance rather than surgery. Additionally, lower-risk RCC, such as small chromophobe RCC, may be managed in a similar way, although with more caution than the renal oncocytomas (RO). The ability to differentiate ROs from chromophobe RCCs, and from other RCCs with a greater chance of metastasis, would guide the physician and patient towards the most appropriate management, whether nephron-sparing surgical resection or conservative surveillance. Consistent accurate diagnosis of ROs is likely to remain elusive until modern molecular biomarkers are identified and applied routinely. This review focuses on the differentiation of renal oncocytomas and chromophobe RCCs. It summarises the history, epidemiology and clinical presentation of the renal neoplasms, explains the diagnostic dilemma, and describes the value, or not, of current molecular markers that are in development to assist in diagnosis of the renal neoplasms.

Efficacy of microbial cell preparation in improving chronic constipation: A randomized, double-blind, placebo-controlled trial

BACKGROUND & AIMS Probiotics is an emerging therapeutic agent which may alleviate the symptoms of constipation. We evaluated the effectiveness of microbial cell preparation (Hexbio(®)) containing fructooligosaccharide, Bifidobacterium and Lactobacillus in improving stool frequency and symptoms of chronic constipation. METHODS A total of 120 constipated adults diagnosed using Rome III criteria were randomized and given either microbial cell preparation or placebo to be consumed twice daily. Follow-up was done after a 7-day intervention based on a questionnaire which includes an assessment of symptom profile and a stool diary. RESULTS During the intervention period, the stool frequency was higher (p = 0.001) in the treatment group. Subjects experienced less straining (p = 0.001) and sensation of incomplete evacuation (p < 0.001), as well as improved stool consistency (p < 0.001) compared to the placebo group. While a higher proportion of subjects in the treatment group had a reduction in anorectal blockage sensation and having to defecate by manual maneuvers, the differences were not statistically significant. CONCLUSION The results suggest that microbial cell preparation is effective in improving stool frequency and stool consistency. Furthermore, it could reduce the symptoms of straining and sensation of incomplete evacuation in adults with chronic functional constipation. MREC REG NO 866.59 (IRB, UMMC, Malaysia).

Patient samples of renal cell carcinoma show reduced expression of TRAF1 compared with normal kidney and functional studies in vitro indicate TRAF1 promotes apoptosis: potential for targeted therapy

Aims: The tumour necrosis factor (TNF) receptor-associated factor (TRAF) family of proteins links the TNF receptor superfamily to cell signalling cascades. TRAF1 is involved in regulation of apoptosis, proliferation, differentiation and stress responses. It has a role in development of several malignancies, but no information for renal cell carcinoma (RCC) is available. Methods: Expression profiles for TRAF1 were investigated in 121 samples of human RCC of various subtypes plus paired normal kidney prepared in tissue microarrays, in comparison with apoptosis (morphology, ApopTag) and mitosis (morphology, proliferating cell nuclear antigen/PCNA). TRAF1 function was tested in vitro in RCC ACHN cells. TRAF1 short interfering RNA (siRNA) was used to inhibit expression of TRAF1 in ACHN cells untreated or treated with cancer therapies known to induce apoptosis (20 Gy X-irradiation and/or 500 IU/mL interferon-alpha). Results: In patient samples, TRAF1 localised to proximal tubular epithelium in normal kidney and was significantly decreased in clear cell RCC as one group (p < 0.01) and all other RCC subclassifications grouped together (p < 0.05). There was little apoptosis identified in any RCC samples. In vitro, TRAF1 siRNA caused significant reduction in TRAF1 expression and a concurrent decrease in apoptosis and increase in proliferative activity (both p < 0.05) in the ACHN RCC cells treated with radiation and interferon-alpha. Conclusion: TRAF1 may have a pro-apoptotic, anti-mitotic role in RCC. The low TRAF1 expression in untreated RCC patient samples compared with normal kidney, and the localisation of TRAF1 to the proximal tubular epithelium from which many RCC originate, may indicate a potential for targeted therapy in RCC.

Automatic ICD-10 multi-class classification of cause of death from plaintext autopsy reports through expert-driven feature selection

Objectives Widespread implementation of electronic databases has improved the accessibility of plaintext clinical information for supplementary use. Numerous machine learning techniques, such as supervised machine learning approaches or ontology-based approaches, have been employed to obtain useful information from plaintext clinical data. This study proposes an automatic multi-class classification system to predict accident-related causes of death from plaintext autopsy reports through expert-driven feature selection with supervised automatic text classification decision models. Methods Accident-related autopsy reports were obtained from one of the largest hospital in Kuala Lumpur. These reports belong to nine different accident-related causes of death. Master feature vector was prepared by extracting features from the collected autopsy reports by using unigram with lexical categorization. This master feature vector was used to detect cause of death [according to internal classification of disease version 10 (ICD-10) classification system] through five automated feature selection schemes, proposed expert-driven approach, five subset sizes of features, and five machine learning classifiers. Model performance was evaluated using precisionM, recallM, F-measureM, accuracy, and area under ROC curve. Four baselines were used to compare the results with the proposed system. Results Random forest and J48 decision models parameterized using expert-driven feature selection yielded the highest evaluation measure approaching (85% to 90%) for most metrics by using a feature subset size of 30. The proposed system also showed approximately 14% to 16% improvement in the overall accuracy compared with the existing techniques and four baselines. Conclusion The proposed system is feasible and practical to use for automatic classification of ICD-10-related cause of death from autopsy reports. The proposed system assists pathologists to accurately and rapidly determine underlying cause of death based on autopsy findings. Furthermore, the proposed expert-driven feature selection approach and the findings are generally applicable to other kinds of plaintext clinical reports.

Intact urothelial barrier function in a mouse model of ketamine-induced voiding dysfunction

Ketamine is a popular choice for young drug abusers. Ketamine abuse causes lower urinary tract symptoms, with the underlying pathophysiology poorly understood. Disruption of urothelial barrier function has been hypothesized to be a major mechanism for ketamine cystitis, yet the direct evidence of impaired urothelial barrier function is still lacking. To address this question, 8-wk-old female C57BL/6J mice were injected intraperitoneally with 30 mg·kg(-1)·day(-1) ketamine for 12 wk to induce ketamine cystitis. A spontaneous voiding spot assay showed that ketamine-treated mice had increased primary voiding spot numbers and smaller primary voiding spot sizes than control mice (P < 0.05), indicating a contracted bladder and bladder overactivity. Consistently, significantly increased voiding frequency was observed in ketamine-treated mice on cystometrograms. These functional experiments indicate that ketamine induces voiding dysfunction in mice. Surprisingly, urothelial permeability in ketamine-treated mice was not changed when measured using an Ussing chamber system with isotopic urea and water. Mouse urothelial structure was also not altered, and intact umbrella cell structure was observed by both transmission and scanning electron microscopy. Furthermore, immunostaining and confocal microscopy confirmed the presence of a well-defined distribution of zonula occuldens-1 in tight junctions and uroplakin in umbrella cells. In conclusion, these data indicate that ketamine injection induces voiding dysfunction in mice but does not necessarily disrupt mouse bladder barrier function. Disruption of urothelial barrier function may not be the major mechanism in ketamine cystitis.

Clinical Prognostic Factors and Survival Outcome in Renal Cell Carcinoma Patients - A Malaysian Single Centre Perspective

BACKGROUND This study concerns clinical characteristics and survival of renal cell carcinoma (RCC) patients in University Malaya Medical Centre (UMMC), as well as the prognostic significance of presenting symptoms. MATERIALS AND METHODS The clinical characteristics, presenting symptoms and survival of RCC patients (n=151) treated at UMMC from 2003-2012 were analysed. Symptoms evaluated were macrohaematuria, flank pain, palpable abdominal mass, fever, lethargy, loss of weight, anaemia, elevated ALP, hypoalbuminemia and thrombocytosis. Univariate and multivariate Cox regression analyses were performed to determine the prognostic significance of these presenting symptoms. Kaplan Meier and log rank tests were employed for survival analysis. RESULTS The 2002 TNM staging was a prognostic factor (p<0.001) but Fuhrman grading was not significantly correlated with survival (p=0.088). At presentation, 76.8% of the patients were symptomatic. Generally, symptomatic tumours had a worse survival prognosis compared to asymptomatic cases (p=0.009; HR 4.74). All symptoms significantly affect disease specific survival except frank haematuria and loin pain on univariate Cox regression analysis. On multivariate analysis adjusted for stage, only clinically palpable abdominal mass remained statistically significant (p=0.027). The mean tumour size of palpable abdominal masses, 9.5±4.3cm, was larger than non palpable masses, 5.3±2.7cm (p<0.001). CONCLUSIONS This is the first report which includes survival information of RCC patients from Malaysia. Here the TNM stage and a palpable abdominal mass were independent predictors for survival. Further investigations using a multicentre cohort to analyse mortality and survival rates may aid in improving management of these patients.

Expression of apoptotic tumour necrosis factor receptor-associated factor, caspase recruitment domain and cell death-inducing DFF-45 effector genes in therapy-treated renal cell carcinoma

Aim:  Dysfunction in apoptosis plays a role in development of renal cell carcinoma (RCC). This investigation aimed to identify expression of apoptosis‐related genes not previously characterized in human RCC.

Renal cell carcinoma: Resistance to therapy, role of apoptosis, and the prognostic and therapeutic target potential of TRAF proteins

Renal cell carcinoma (RCC) is the commonest of the renal neoplasms. Although surgery and cryoablation are successful curative treatments for localized RCC, most patients are diagnosed with advanced or metastatic RCC, which has a poor prognosis. RCC are a heterogeneous set of cancers that have traditionally been classified and staged using cellular characteristics, size, local extension and distant metastases. Current staging systems provide good prognostic information, but it is very likely that the identification of new more accurate and predictive prognostic markers, not currently included in traditional staging systems, will improve the outcome for RCC patients. For this reason, increased knowledge of the underlying molecular characteristics of RCC development and progression is necessary. In most cancers, but especially RCC, deregulated control of apoptosis contributes to cancer growth by aberrantly extending cell viability and facilitating resistance to cancer therapies. Here we present the hypothesis that select members of the tumor necrosis factor (TNF) superfamily, the TNF receptor-associated factors (TRAFs), have a role in RCC apoptosis and may have prognostic significance for RCC. Candidate biomarkers for RCC are few, and the TRAFs may be important inclusions in panels of biomarkers for RCC. TRAFs may also be potential molecular targets for new therapies, either through their ability to promote apoptosis in the cancers themselves, or through their ability to modulate the immune defence against cancer progression. Some support data are presented here for our hypothesis. However, these novel concepts need further careful analysis to allow clinicians and oncologists any assistance for earlier detection of RCC and for characterizing patients with RCC for individualised targeted therapy.

Automatic Text Classification of ICD-10 Related CoD from Complex and Free Text Forensic Autopsy Reports

Forensic autopsy focuses on revealing the cause of death (CoD) by examination of a dead body. In this research study, various feature extraction schemes, feature value representation schemes and text classification algorithms have been applied on forensic autopsy reports to discover the suitable feature extraction approach, feature value representation approach and text classification approach. From experimental results, it was found that the unigram features outperformed bigram, trigram and hybrids of unigram, bigram and trigram features. Moreover, TF and TFiDF feature value representation schemes were proven more suitable than binary representation and normalized TFiDF schemes. Finally, SVM decision models outperformed RF and NB.

Tumour necrosis factor receptor-associated factor-1 (TRAF-1) expression is increased in renal cell carcinoma patient serum but decreased in cancer tissue compared with normal: potential biomarker significance

Summary Renal cell carcinoma (RCC) generally has a poor prognosis because of late diagnosis and metastasis. We have previously described decreased tumour necrosis factor receptor-associated factor-1 (TRAF-1) in RCC compared with paired normal kidney in a patient cohort in Australia. In the present study, TRAF-1 expression in clear cell RCC (ccRCC) and normal kidney was again compared, but in a cohort from University Malaya Medical Centre. Serum TRAF-1 was also evaluated in RCC and normal samples. Immunohistochemistry with automated batch staining and Aperio ImageScope morphometry was used to compare TRAF-1 in 61 ccRCC with paired normal kidney tissue. Serum from 15 newly diagnosed and untreated ccRCC and 15 healthy people was tested for TRAF-1 using ELISA. In this cohort, TRAF-1 was highly expressed in proximal tubular epithelium of normal kidney, and significantly decreased in ccRCC tissue (p < 0.001). Conversely, TRAF-1 in serum from ccRCC patients was significantly increased over control serum (132 ± 30 versus 54 ± 14 pg/mL, respectively; p = 0.013). Decreased TRAF-1 in RCC tissue, reported previously, was confirmed. This, along with significantly increased serum TRAF-1 may indicate the protein is actively secreted during development and progression of ccRCC. Therefore, the increased serum TRAF-1 may be a useful non-invasive indicator of RCC development.