Demethylases of H3 lysine 27 (H3K27) expression in urothelial carcinoma (UC) of the urinary bladder

BACKGROUND

Ubiquitously Transcribed Tetracopeptide Repeat on X Chromosome (UTX) and Jumonji Domain-Containing Protein 3 (JMJD3) are histone H3 lysine 27 (H3K27) demethylases that are found to play tumour suppressor or oncogenic roles in many cancers. However, their roles in urothelial carcinoma (UC) have not been well studied.

OBJECTIVE

This study investigated UTX and JMJD3 protein expression patterns in UC and assess their clinical significance.

PATIENTS AND METHODS

Immunohistochemistry (IHC) method was performed on formalin-fixed paraffin-embedded (FFPE) of UC tissues and compared to the normal bladder tissues from the autopsy specimen. The staining intensity of FFPE tissues were captured with the nuclear and overall positive pixels quantified using Aperio ImageScope software.

RESULTS

JMJD3 protein uptake was present in both nucleus and cytoplasm but UTX protein was predominantly seen in the cytoplasm of UC tissue. UTX was under expressed whereas JMJD3 was over expressed in UC compared to normal bladder. UTX and JMJD3 were not related to clinical stage and grade. However, significant association between JMJD3 expression and invasiveness of tumour (p<0.05) was noted, especially in MIBC group (88.9%). UTX and JMJD3 did not yield any significance as prognostic factors for diseasespecific survival.

CONCLUSIONS

Low expression of UTX protein in UC may indicate possible loss of its tumour suppressor activity and higher JMJD3 protein expression may indicate oncogenic activity. Hence, JMJD3 protein could be a potential diagnostic biomarker in detecting bladder UC of higher stages. Further investigation needed to study the dysregulation of this protein expression with associated gene expression.

The correlation of EMT and p53 immunohistochemical markers with cisplatin resistance in muscle invasive bladder cancer patients: A single-centred study

INTRODUCTION

Although epithelial-mesenchymal transition (EMT) and p53 have been established to play a pivotal role in the aggressiveness of muscle-invasive bladder cancer (MIBC), its pathological correlation to cisplatin treatment in the Malaysian patient cohort is lacking. This study aimed to evaluate the association of EMT markers, e-cadherin, vimentin and actin, as well as tumour suppressor gene, p53, in cisplatin-receiving MIBC patients.

MATERIALS AND METHODS

Formalin-fixed paraffinembedded (FFPE) blocks of muscle-invasive bladder cancer patients receiving cisplatin-based chemotherapy between January 2010 to December 2020 were traced. Immunohistochemistry staining was performed on traced blocks using antibodies to e-cadherin, vimentin and actin, and p53.

RESULTS

p53 and e-cadherin were stained positive in most cases (p=0.515 and 0.242 respectively), although e-cadherin showed stronger positive expression in pre-cisplatin receiving MIBC cases. All the cases stained negative for actin and vimentin except for faint staining observed in one pre-cisplatin case.

CONCLUSION

Although this study does not show a significant correlation between EMT markers and p53 with cisplatin-responsiveness in MIBC patients, the results serve as preliminary findings on the heterogeneous outcomes of molecular staining in the Malaysian MIBC patient cohort.

FISHing for 1p19q codel in oligodendroglioma

Together with isocitrate dehydrogenase (IDH) mutation, co-deletion of 1p19q (1p19q codel) is a prerequisite for diagnosis of oligodendroglioma, making it imperative that histopathology laboratories introduce testing for 1p19q codel. To date there is still no consensus reference range and cut-offs that confirm deletion of 1p or 19q. We embarked on determining our reference range in 11 formalinfixed, paraffin-embedded non-neoplastic brain tissue using fluorescence in situ hybridisation (FISH) with the Vysis 1p36/1q25 and 19q13/19p13 FISH Probe Kit (Abbott Molecular Inc., USA). At same time we attempted to validate our methodology in 13 histologically-confirmed IDH-mutant oligodendrogliomas. For 1p, percentage cells with deletion (range=8-23%; mean±SD = 15.73±5.50%) and target: control (1p36:1q25) ratio (range = 0.89-0.96; mean±SD = 0.92±0.03) in non-neoplastic brain, differed significantly (p<0.000) from oligodendroglioma (percentage cells with deletion: range = 49-100%; mean±SD = 82.46±15.21%; target:control ratio range:0.50-0.76; mean±SD = 0.59±0.08). For 19q, percentage cells with deletion (range = 7-20%; mean±SD = 12.00±3.49%) and target:control (19q13/19p13) ratio (range:0.90-0.97; mean±SD = 0.94±0.02) in non-neoplastic brain also differed significantly from oligodendroglioma (percentage cells with deletion: range = 45-100%; mean±SD = 82.62±18.13%; target:control ratio range:0.50-0.78; mean±SD = 0.59±0.09). Using recommended calculation method, for diagnosis of 1p deletion, percentage of cells showing deletion should be >32-33% and/or target:control ratio <0.83. For 19q, percentage of cells showing deletion should be >22% and target:control ratio <0.88. Using these cut-offs all 13 oligodendroglioma demonstrated 1p19q codel.

Carbonic anhydrase IX immunohistochemistry has potential to predict renal cell carcinoma outcomes: A systematic review and meta-analyses

INTRODUCTION

Tissue biomarker carbonic anhydrase IX (CAIX) is purported to have prognostic value for renal cell carcinoma (RCC) but contradicting findings from previous studies have also been documented. This study aims to perform a systematic review and meta-analysis on the role of CAIX in RCC disease progression.

MATERIALS AND METHODS

Following the preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines, online searches of multiple databases were performed to retrieve articles from their inception until December 2017. Inclusion criteria included all English-based original articles of immunohistochemistry (IHC) studies investigating CAIX expression in human RCC tissue. Four articles were finally selected for meta-analysis with a total of 1964 patients. Standard meta-analysis methods were applied to evaluate the role of CAIX in RCC prognosis. The relative risk (RR) and its 95% confidence interval (CI) were recorded for the association between biomarker and prognosis, and data were analysed using MedCalc statistical software.

RESULTS

The meta-analysis showed that high CAIX expression was associated with low tumour stage (RR 0.90%, 95% CI 0.849-0.969, p= 0.004), low tumour grade (RR 0.835%, 95% CI 0.732-0.983, p= 0.028), absence of nodal involvement (RR 0.814%, 95% CI 0.712-0.931, p= 0.003) and better ECOS-PS index (RR 0.888%, 95% CI 0.818-0.969, p= 0.007). The high tissue CAIX expression in RCC is hence an indication of an early malignancy with a potential to predict favourable disease progression and outcome.

CONCLUSION

The measurement of this marker may be beneficial to determine the course of the illness. It is hoped that CAIX can be developed as a specific tissue biomarker for RCC in the near future.

Screening for microsatellite instability in colorectal carcinoma: Practical utility of immunohistochemistry and PCR with fragment analysis in a diagnostic histopathology setting

Since 2014, the National Comprehensive Cancer Network (NCCN) has recommended that colorectal carcinoma (CRC) be universally tested for high microsatellite instability (MSI-H) which is present in 15% of such cancers. Fidelity of resultant microsatellites during DNA replication is contingent upon an intact mismatch repair (MMR) system and lack of fidelity can result in tumourigenesis. Prior to commencing routine screening for MSI-H, we assessed two commonly used methods, immunohistochemical (IHC) determination of loss of MMR gene products viz MLH1, MSH2, MSH6 and PMS2 against PCR amplification and subsequent fragment analysis of microsatellite markers, BAT25, BAT26, D2S123, D5S346 and D17S250 (Bethesda markers) in 73 unselected primary CRC. 15.1% (11/73) were categorized as MSI-H while deficient MMR (dMMR) was detected in 16.4% (12/73). Of the dMMR, 66.7% (8/12) were classified MSI-H, while 33.3% (4/12) were microsatellite stable/low microsatellite instability (MSS/MSI-L). Of the proficient MMR (pMMR), 95.1% (58/61) were MSS/MSI-L and 4.9% (3/61) were MSI-H. The κ value of 0.639 (standard error =0.125; p = 0.000) indicated substantial agreement between detection of loss of DNA mismatch repair using immunohistochemistry and the detection of downstream microsatellite instability using PCR. After consideration of advantages and shortcomings of both methods, it is our opinion that the choice of preferred technique for MSI analysis would depend on the type of laboratory carrying out the testing.

AC6 is the major adenylate cyclase forming a diarrheagenic protein complex with cystic fibrosis transmembrane conductance regulator in cholera

The World Health Organization(WHO) has reported a worldwide surge in cases of cholera caused by the intestinal pathogen Vibrio cholerae, and, combined, such surges have claimed several million lives, mostly in early childhood. Elevated cAMP production in intestinal epithelial cells challenged with cholera toxin (CTX) results in diarrhea due to chloride transport by a cAMP-activated channel, the cystic fibrosis transmembrane conductance regulator (CFTR). However, the identity of the main cAMP-producing proteins that regulate CFTR in the intestine and may be relevant for secretory diarrhea is unclear. Here, using RNA-Seq to identify the predominant AC isoform in mouse and human cells and extensive biochemical analyses for further characterization, we found that the cAMP-generating enzyme adenylate cyclase 6 (AC6) physically and functionally associates with CFTR at the apical surface of intestinal epithelial cells. We generated epithelium-specific AC6 knockout mice and demonstrated that CFTR-dependent fluid secretion is nearly abolished in AC6 knockout mice upon CTX challenge in ligated ileal loops. Furthermore, loss of AC6 function dramatically impaired CTX-induced CFTR activation in human and mouse intestinal spheroids. Our finding that the CFTR-AC6 protein complex is the key mediator of CTX-associated diarrhea may facilitate development of antidiarrheal agents to manage cholera symptoms and improve outcomes.

Personalized medicine in CF: from modulator development to therapy for cystic fibrosis patients with rare CFTR mutations

Cystic fibrosis (CF) is the most common life-shortening genetic disease affecting ~1 in 3,500 of the Caucasian population. CF is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. To date, more than 2,000 CFTR mutations have been identified, which produce a wide range of phenotypes. The CFTR protein, a chloride channel, is normally expressed on epithelial cells lining the lung, gut, and exocrine glands. Mutations in CFTR have led to pleiotropic effects in CF patients and have resulted in early morbidity and mortality. Research has focused on identifying small molecules, or modulators, that can restore CFTR function. In recent years, two modulators, ivacaftor (Kalydeco) and lumacaftor/ivacaftor (Orkambi), have been approved by the U.S. Food and Drug Administration to treat CF patients with certain CFTR mutations. The development of these modulators has served as proof-of-concept that targeting CFTR by modulators is a viable therapeutic option. Efforts to discover new modulators that could deliver a wider and greater clinical benefit are still ongoing. However, traditional randomized controlled trials (RCTs) require large numbers of patients and become impracticable to test the modulators' efficacy in CF patients with CFTR mutations at frequencies much lower than 1%, suggesting the need for personalized medicine in these CF patients.

Oral ketamine induced pathological changes of the urinary tract in a rat model

INTRODUCTION

In recent years, prolonged ketamine abuse has been reported to cause urinary tract damage. However, there is little information on the pathological effects of ketamine from oral administration. We aimed to study the effects of oral ketamine on the urinary tract and the reversibility of these changes after cessation of ketamine intake.

METHODS

Rats were fed with illicit (a concoction of street ketamine) ketamine in doses of 100 (N=12), or 300 mg/kg (N=12) for four weeks. Half of the rats were sacrificed after the 4-week feeding for necropsy. The remaining rats were taken off ketamine for 8 weeks to allow for any potential recovery of pathological changes before being sacrificed for necropsy. Histopathological examination was performed on the kidney and urinary bladder.

RESULTS

Submucosal bladder inflammation was seen in 67% of the rats fed with 300 mg/kg illicit ketamine. No bladder inflammation was observed in the control and 100 mg/kg illicit ketamine groups. Renal changes, such as interstitial nephritis and papillary necrosis, were observed in rats given illicit ketamine. After ketamine cessation, no inflammation was observed in the bladder of all rats. However, renal inflammation remained in 60% of the rats given illicit ketamine. No dose-effect relationship was established between oral ketamine and changes in the kidneys.

CONCLUSION

Oral ketamine caused pathological changes in the urinary tract, similar to that described in exposure to parenteral ketamine. The changes in the urinary bladder were reversible after short-term exposure.

Cytoskeletal architecture and cell motility remain unperturbed in mouse embryonic fibroblasts from Plk3 knockout mice

Polo-like kinase 3 (Plk3) is best known for its involvement in cell cycle checkpoint regulation following exposure to cytotoxicants or induction of DNA damage. Yet, Plk3 has also been implicated in roles beyond those of cellular responses to DNA damage. Here, we have investigated the proposition, suggested by the Plk literature, that Plk3 regulates cytoskeletal architecture and cell functions mediated by the cytoskeleton. To this end, we have assayed mouse embryonic fibroblasts (MEFs) generated from both Plk3 knockout and wild-type mice. In particular, we asked whether Plk3 is involved in actin fiber and microtubule integrity, cell migration, cell attachment, and/or cell invasion. Our results demonstrate that functional Plk3 is not critical for the regulation of cytoskeletal integrity, cell morphology, cell adhesion, or motility in MEFs.

Rapid Prototyping of Heterotypic Cell-Cell Contacts

Disparities in cellular behaviour between cultures of a single cell type and heterogeneous co-cultures require constructing spatially-defined arrays of multiple cell types. Such arrays are critical for investigating cellular properties as they exist in vivo. Current methods rely upon covalent surface modification or external physical micromanipulation to control cellular organization on a limited range of substrates. Here, we report a direct approach for creating co-cultures of different cell types by microcontact printing a photosensitive cell resist. The cell-resistant polymer converts to cell adhesive 0 with light exposure, thus the initial copolymer pattern dictates the position of both cell types. This strategy enables straightforward preparation of tailored heterotypic cell-cell contacts on materials ranging from polymers to metallic substrates.

SNP array technology: an array of hope in breast cancer research

Breast cancer is the most common malignancy in women worldwide. The incidence of breast cancer in Malaysia is lower compared to international statistics, with peak occurrence in the age group between 50 to 59 years of age and mortality rates of 18.6%. Despite current diagnostic and prognostic methods, the outcome for individual subjects remain poor. This is in part due to breast cancers' wide genetic heterogeneity. Various platforms for genetics studies are now employed to determine the identity of these genetic abnormalities, including microarray methods like high density single-nucleotide-polymorphism (SNP) oligonucleotide arrays which combine the power of chromosomal comparative genomic hybridization (cCGH) and loss of heterozygosity (LOH) in the offering of higher-resolution mappings. These platforms and their applications in highlighting the genomic alteration frameworks manifested in breast carcinoma will be discussed.

Micropatterning different cell types with microarray amplification of natural directional persistence

In vivo, different cell types assemble in specific patterns to form functional tissues. Reproducing this process in vitro by designing scaffold materials to direct cells precisely to the right locations at the right time is important for the next generation of biomaterials. Here, using microarray amplification of natural directional persistence (MANDIP), simultaneous assembly of fibroblasts and endothelial cells is demonstrated by directing their long-range migration. Amplification of the directional persistence occurs through morphology-induced polarity and the asymmetric positioning of individual microsized adhesive islands that restrict lamellipodia attachment, and thus migration, to one preset direction. Quantitative analysis of cell migration on different MANDIP designs yields insight to the relative importance of the asymmetric island shapes and their arrangement. The approach enables spatial patterning of different cell types with micrometer-scale precision over large areas for investigation of cell-cell interactions within complex tissue architectures.

Imaging findings of a primary bladder maltoma

Secondary involvement of the urinary bladder in non-Hodgkin's lymphoma is relatively common; however, primary malignant lymphoma of this organ is extremely rare. The most common type of primary bladder lymphoma is a low-grade B-cell mucosa-associated lymphoid tissue (MALT) lymphoma. We report here on the imaging findings of a primary bladder lymphoma with bone marrow infiltration.

Subcutaneous metastasis of olfactory neuroblastoma - an uncommon presentation

Olfactory neuroblastoma is a rare, slow growing, malignant tumour of neuroectodermal origin that begins in neuroepithelial cells of the olfactory membrane. A metastatic rate of 20% to 60% is reported with the most common site being the cervical lymph node. Other sites include the parotid glands, skin, lungs, bone, liver, orbit, spinal cord and spinal canal. We describe a case of olfactory neuroblastoma presented to us with scalp metastasis.

Comparison of breast cancer in Indonesia and Malaysia--a clinico-pathological study between Dharmais Cancer Centre Jakarta and University Malaya Medical Centre, Kuala Lumpur

INTRODUCTION

The age standardised incidence rate (ASR) of breast cancer in Malaysia which is a high middle- income country is similar to Indonesia, a low middle-income country. (Globocan 2008) It is however unknown whether the presentation of breast cancer differs between these two countries.

OBJECTIVE

We compared the stage, age at presentation, and pathological characteristics of breast cancer between two tertiary hospitals in Indonesia and Malaysia; Dharmais Cancer Centre (DCC), which is the national cancer referral centre in Indonesia, and University Malaya Medical Centre (UMMC), which is an academic hospital with established breast oncology services in Kuala Lumpur. One thousand, one hundred and fourteen consecutive women (477 in UMMC: 637 in DCC) who were newly diagnosed with breast cancer between January and December, 2010 were included. Patient's age, TNM stage at presentation, and pathological characteristics were compared. Estrogen receptor (ER) and progesterone receptor (PR) were considered positive if 10% or greater of invasive cell nuclei were stained while HER2 was considered positive with an immunohistochemistry staining intensity of 3+ . Logistic regression analyses were performed to identify differences.

RESULTS

Median age at diagnosis was 52 years in UMMC and 47 years in DCC, whereby patients in DCC were more likely to be very young at diagnosis (aged < 35 years) compared to their counterparts in UMMC (Odds ratio (OR): 2.09; 95%CI: 1.32-3.31). Approximately one third of patients in UMMC presented with TNM stage III or IV, compared to 63% in DCC. Patients in DCC were three times more likely to present with metastatic breast cancer compared to patients in UMMC (OR: 3.01; 95% CI: 2.02-4.48). The percentage of low grade tumours in DCC was higher than in UMMC (28% vs 11% respectively), and the difference persisted even after multivariate adjustment. Although the frequency of ER and PR positivity appeared to be higher in UMMC (65% and 55% respectively) compared to DCC (48% and 40% respectively), these differences were not statistically significant following adjustment for age, stage, HER2 status and grade. The frequency of HER2 positivity was 45% in DCC compared to 26% in UMMC, and remained significantly higher even after multivariate adjustment (multivariate OR:1.76; 95%CI:1.25-2.47, in DCC compared to UMMC). The proportion of triple negative breast cancer was however similar in the two centres (19% in UMMC vs 21% in DCC).

CONCLUSION

Indonesian women with breast cancer seem to present at a younger age and at later stages compared to Malaysian women. Their tumors were more likely to be of low grade and HER2 positive, even after adjustment for other factors, while hormone receptor positivity proved similar in the two groups. The higher HER2 positivity rate in Indonesian patients warrants further study.

Epidermal inclusion cyst of the breast: a rare benign entity

Epidermal inclusion cyst (EIC) arising from the breast is an uncommon benign condition. We report two cases of enlarging EIC of the breast in two women in their forties. The diagnosis of this condition may not be straightforward with imaging alone if an EIC presents as an enlarging lump in the breast and mimics a benign breast lesion, most commonly a fibroadenoma or malignant lesion with benign imaging features. Excision is usually recommended for a definite histopathological diagnosis and for the prevention of potential risks of malignant transformation. Asymptomatic stable lesions do not require treatment; biopsy is unnecessary, and follow-up imaging suffices if typical sonographic and clinical findings are found.

A stable, label-free optical interferometric biosensor based on TiO2 nanotube arrays

Optical interferometry of a thin film array of titanium dioxide (TiO2) nanotubes allows the label-free sensing of rabbit immunoglobulin G (IgG). A protein A capture probe is used, which is immobilized on the inner pore walls of the nanotubes by electrostatic adsorption. Control experiments using IgG from chicken (which does not bind to protein A) confirms the specificity of the protein A-modified TiO2 nanotube array sensor. The aqueous stability of the TiO2 nanotube array was examined and compared with porous silica (SiO2), a more extensively studied thin film optical biosensor. The TiO2 nanotube array is stable in the pH range 2 to 12, whereas the porous SiO2 sensor displays significant degradation at pH > 8.

Aneurysmal bone cyst of the maxilla

An aneurysmal bone cyst is a rare bone lesion. Its origin and precise nature remain unknown. It is seen as a locally-destructive, rapidly expandable, benign multicystic mass. We report a 17-year-old boy with an aneurysmal bone cyst of the maxilla, with extensive local involvement and bony destruction that was treated surgically. There was no recurrence noted after four years of follow-up.