Increased tube formation and up-regulation of FGFR3 mRNA expression in microvascular endothelial cell by exosomes derived from SW480-7

INTRODUCTION

Extracellular vesicles (exosome-like vesicles) are small membrane vesicles ranging from 20-200nm in size that are released by various cells into the extracellular space. These extracellular vesicles play a major role in cell-to-cell communication and contain materials, such as proteins, mRNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). The effect of exosomes derived from an invasive colon cancer cell line on angiogenesis is unclear. Hence, the aim of this study is to investigate the effect of exosomes derived from an invasive colon cancer cell line on angiogenesis of endothelial cells.

MATERIALS AND METHODS

In the present study, the exosomes from the cell culture supernatants of an invasive colon cancer cell line SW480-7 were characterised. The effect on tube formation and expression of angiogenic genes in a microvascular endothelial cell, telomerase-immortalised microvascular endothelial cell (TIME) was examined after co-cultured with exosomes secreted from SW480-7.

RESULTS

Zetasizer result showed average diameter of exosomes derived from SW480-7 was 246.2 nm and morphological analysis showed the size of majority of exosomes were less than 200 nm. Results showed that exosomes derived from SW480-7 increased tube formation and up-regulated FGFR3 mRNA expression in TIME.

CONCLUSION

Our findings suggest that exosomes derived from SW480-7 increased tube formation and up-regulated expression of FGFR3 mRNA in TIME.

HER3 overexpression and hypomethylation in colorectal adenocarcinoma

INTRODUCTION

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cancer in Malaysia. Despite advanced therapies, many cases of recurrence and resistance have been reported. Aberrant DNA methylation of HER3 has been implicated in carcinogenesis of CRC mainly through the regulation of gene expression. Hence, the objective of this study was to determine the status of HER3 DNA methylation and its effects on gene expression in CRC.

MATERIALS AND METHODS

Fifty-nine of archival formalin-fixed, paraffin-embedded CRC cases with the adjacent normal colon tissues were retrieved. Manual micro-dissection was performed prior to RNA and DNA extraction. HER3 gene expression and DNA methylation status was evaluated by qPCR and methylation-specific PCR (MSP) techniques respectively.

RESULTS

Upregulation of HER3 mRNA was found in CRC tissue compared to its adjacent normal colon tissue (8.04-fold). Of 59 CRC samples, 8.5% were methylated and 91.5% were unmethylated (hypomethylation). In the adjacent normal colon tissues, methylated and unmethylated tissue were observed in 6.8%and 93.2% respectively. DNA methylation of HER3 showed a significant association with tumour differentiation and tumour location.

CONCLUSION

This study showed upregulation and hypomethylation of the HER3 gene in CRC cases. Epigenetic alterations were also found in the adjacent normal colon tissues. Thus, upregulation and hypomethylation of HER3 may play a key role in carcinogenesis of CRC. Hypomethylation of CpG islands might be associated with early steps during carcinogenesis. The findings of this biomarker serve a powerful approach to improve the current diagnostic and therapeutic measures.

Differential time course of glycogen synthase kinase-3 inhibition in experimental autoimmune encephalomyelitis

INTRODUCTION

GSK-3 is an immune regulator that plays a role in the modulation of cytokine-producing effector T cells associated with inflammation and demyelination of the CNS in EAE.

OBJECTIVE

This study aimed to evaluate the treatment paradigm of a single dose of GSK-3 inhibitor administration at various time courses for the protection of the CNS from EAE.

MATERIALS AND METHODS

Effects of GSK-3 inhibition on intracellular cytokine levels were evaluated from in vitro naïve CD4+ T cell cultures. Immunized C57BL/6 female mice with MOG_35-55 in conjunction with CFA and Ptx were used as a chronic inflammatory EAE disease model. Tideglusib (NP12), a Thiadiazolidinone class, selective, and non-ATP competitive GSK-3 inhibitor, was injected intraperitoneally at pre-EAE, same-day of immunization or disease onset. After 30 days post-immunization, brain, and spinal cord tissues were collected for inflammation and demyelination analysis by H&E and luxol fast blue staining, respectively, whereas cytokine profiles of the serum were assessed by cytokine beads array.

RESULTS

The inhibition of GSK-3 in CD4+ T cells increased IL-10 production. The administration of Tideglusib during pre-EAE and same-day, but not during disease onset, significantly reduced clinical symptoms and delayed disease onset. Histopathological analysis of spinal cord tissues showed a significant decline in the number of inflammatory cell infiltration with a concomitant reduction in demyelination through the blocking of GSK-3, especially during pre-EAE and sameday. Upregulation of IL-10 via GSK-3 inhibition coincided with the downregulation of cytokineassociated effector T cells, including IFN-γ, IL-9, IL-17A, IL-17F, IL-21, and IL-23. Increased IL-4 production, however, was only significant in the pre-EAE group.

CONCLUSION

The neuroprotective effects of Tideglusib against EAE are time-dependent. Downregulation of Th1 and Th17 hallmark cytokines by Tideglusib in EAE may be associated with IL-10 production.

Cutaneous involvement of multiple myeloma

Cutaneous multiple myeloma (MM) is a rare disease. It can be primary or secondary in origin. The secondary type is further classified into specific and nonspecific types. The specific type is uncommon and is known as a secondary cutaneous plasmacytoma. We report a case of secondary cutaneous plasmacytoma in a 58-year-old man who had a history of plasma cell tumour of the lung and multiple myeloma. He achieved complete remission after the completion of chemotherapy and autologous stem cell transplant (ASCT). However, five months later, he developed multiple erythematous nodules on the whole body. Skin biopsy revealed diffuse neoplastic cells infiltrate in the reticular dermis with sparing of the upper papillary dermis and epidermis. The neoplastic cells were monotonous and homogenous with variable degrees of cytological atypia. Occasional cells showed distinctive plasma cell features. Plasma cell lineage was confirmed with CD138. The cells were immunoreactive to Kappa. Ki-67 was greater than 90%. They were non-immunoreactive to CD45, CD3, CD20, CD79 alpha and CK AE1/AE3. The findings were consistent with secondary cutaneous plasmacytoma. Our case illustrates that MM may present with nonspecific dermatological manifestations. As specific cutaneous involvement of MM is very uncommon; a high degree of clinical suspicion, detailed medical history and histopathological examination are required to arrive at an early diagnosis.

Cyclooxygenase-2 expression in clear cell renal cell carcinoma

INTRODUCTION

Cyclooxygenase-2 (COX-2) promotes carcinogenesis by inducing proliferation and angiogenesis while decreasing apoptosis and immunosuppressive activity. It is overexpressed in many malignancies including renal cell carcinoma (RCC). The aim of this study was to investigate COX-2 expression in clear cell RCC and its association with tumour grades and demographic parameters.

MATERIALS AND METHODS

Thirty-six clear cell RCC cases were selected. There were 21 (58.3%) men and 15 (41.7%) women with median age of 56.6 years (range: 16-74 years). Chinese constituted 16 (44.4%) of the cases; Malays 14 (38.9%) cases and Indian 6 (16.7%) cases. There were 6 (16.7%) grade 1, 20 (55.6%) grade 2, 10 (27.8%) grade 3 and none was grade 4. The paraffin embedded tissues were cut at 4 μm thick and stained with COX-2 monoclonal antibody.

RESULTS

Eighteen (50%) of the RCC cases were immunopositive, of which all showed strong positivity. The immunopositive cases showed cytoplasmic membrane positivity.

CONCLUSION

There was no significant association between COX-2 expression with grade, age, sex and ethnicity (p=0.457, p=0.054, p=0.389 and p=0.568 respectively). Strong positivity of COX-2 suggest that COX-2 may play a role in cell proliferation and in carcinogenesis.

Single-species versus dual-species probiotic supplementation as an emerging therapeutic strategy for obesity

BACKGROUND AND AIM

Recent studies have reported beneficial effects of specific probiotics on obesity. However, the difference in the anti-obesity effects of probiotics as single species and dual species is still uncertain. Therefore, we aimed to compare the efficacy of single and dual species of bacteria on markers of obesity in high-fat diet-induced obese rats.

METHODS AND RESULTS

A total of 40 male Sprague-Dawley rats were assigned to one of five groups of varying diets as follows: standard diet, high fat diet (HFD), HFD supplemented with Lactobacillus casei strain Shirota, HFD supplemented with Bifidobacterium longum and HFD supplemented with a mixture of these two bacterial species. After 15 weeks of supplementation, the animals were examined for changes in body weight, body fat, total count of bacteria in fecal, blood serum lipid profile, leptin, adiponectin and inflammatory biomarkers. Histological analysis of the liver and adipose tissue was performed and the hepatic mRNA expression levels of genes related to lipid metabolism were measured. It was found that probiotic supplementation of either B. longum or a mixture of B. longum and LcS bacteria significantly reduced weight and triglycerides in the HFD groups. Supplementation of B. longum bacteria showed better results in terms of modulating leptin level, fat mass, adipocyte size and lipoprotein lipase expression, as well as increasing adiponectin and peroxisome proliferator-activated receptors-γ expression compared to dual species of bacteria. No significant differences were observed in the total count of fecal bacteria, glucose and inflammatory biomarker levels between supplemented groups.

CONCLUSIONS

B. longum supplementation in obesity was more beneficial in metabolic profile changes than the mixture species.

Solitary fibrous tumour of the chest wall

Extrapleural solitary fibrous tumours (SFTs) are rare tumours characterized by patternless spindle cells with haemangiopericytoma-like vascular spaces. Previously the tumours have been classified as haemangiopericytoma, an entity that is now considered obsolete. We report a case of extrapleural SFT arising in the soft tissue of the chest wall. The patient was a 31-year-old Malay lady presenting with a mobile swelling of the right chest wall for more than five years. During excision the tumour was noted to be well-circumscribed and yellowish in colour, giving an impression of lipoma. Microscopically, the tumour had patternless architecture, characterized by hypocellular and hypercellular areas. It was composed of uniform, spindle-shaped cells displaying oval nuclei, inconspicuous nucleoli, pale cytoplasm and indistinct cell borders. The mitotic count was 2 per 10 HPF. Branching, medium-sized thin-walled blood vessels in a haemangiopericytomatous growth pattern, some with hyalinised wall were identified. The neoplastic cells were immunoreactive to CD99 and CD34 and were non-immunoreactive to Desmin, Smooth Muscle Actin, S100 protein and EMA. We elucidate the challenges in diagnosing this tumour in this unusual location.

Amelioration of paracetamol-induced hepatotoxicity in rat by the administration of methanol extract of Muntingia calabura L. leaves

Muntingia calabura L. is a tropical plant species that belongs to the Elaeocarpaceae family. The present study is aimed at determining the hepatoprotective activity of methanol extract of M. calabura leaves (MEMC) using two models of liver injury in rats. Rats were divided into five groups (n=6) and received 10% DMSO (negative control), 50 mg/kg N-acetylcysteine (NAC; positive control), or MEMC (50, 250, and 500 mg/kg) orally once daily for 7 days and on the 8th day were subjected to the hepatotoxic induction using paracetamol (PCM). The blood and liver tissues were collected and subjected to biochemical and microscopical analysis. The extract was also subjected to antioxidant study using the 2,2-diphenyl-1-picrylhydrazyl-(DPPH) and superoxide anion-radical scavenging assays. At the same time, oxygen radical antioxidant capacity (ORAC) and total phenolic content were also determined. From the histological observation, lymphocyte infiltration and marked necrosis were observed in PCM-treated groups (negative control), whereas maintenance of hepatic structure was observed in group pretreated with N-acetylcysteine and MEMC. Hepatotoxic rats pretreated with NAC or MEMC exhibited significant decrease (P<0.05) in ALT and AST enzymes level. Moreover, the extract also exhibited good antioxidant activity. In conclusion, MEMC exerts potential hepatoprotective activity that could be partly attributed to its antioxidant activity and, thus warrants further investigations.

Hepatoprotective Activity of Methanolic Extract of Bauhinia purpurea Leaves against Paracetamol-Induced Hepatic Damage in Rats

In an attempt to further establish the pharmacological properties of Bauhinia purpurea (Fabaceae), hepatoprotective potential of methanol extract of B. purpurea leaves (MEBP) was investigated using the paracetamol- (PCM-) induced liver toxicity in rats. Five groups of rats (n = 6) were used and administered orally once daily with 10% DMSO (negative control), 200 mg/kg silymarin (positive control), or MEBP (50, 250, and 500 mg/kg) for 7 days, followed by the hepatotoxicity induction using paracetamol (PCM). The blood samples and livers were collected and subjected to biochemical and microscopical analysis. The extract was also subjected to antioxidant study using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay with the total phenolic content (TPC) also determined. From the histological observation, lymphocyte infiltration and marked necrosis were observed in PCM-treated groups (negative control), whereas maintenance of the normal hepatic structural was observed in group pretreated with silymarin and MEBP. Hepatotoxic rats pretreated with silymarin or MEBP exhibited significant decrease (P < 0.05) in ALT and AST enzyme level. Moreover, the extract also exhibited antioxidant activity and contained high TPC. In conclusion, MEBP exerts potential hepatoprotective activity that could be partly attributed to its antioxidant activity and high phenolic content and thus warrants further investigation.

Antiulcer activity of methanol extract of Melastoma malabathricum leaves in rats

OBJECTIVE

To determine the potential antiulcer activity of methanol extract of Melastoma malabathricum leaves (MEMM) using various established rat models.

MATERIALS AND METHODS

Ten groups of rats were used and orally administered 10% DMSO (negative control), 100 mg/kg ranitidine (positive control) or MEMM (50, 250 and 500 mg/kg) followed by gastric ulcer induction either using ethanol or indomethacin. The stomachs were collected and subjected to macroscopic and microscopic analyses.

RESULTS

MEMM exhibited significant (p < 0.05) antiulcer activity in the ethanol, but not in the indomethacin-induced gastric ulcer model. The percentage of antiulcer activity for 50-500 mg/kg MEMM ranged between 3 and 75%, respectively. The gross observations were supported by histological findings. MEMM also aggravated the indomethacin-induced gastric ulcer, leading to an increase in ulcer area formation and ulcer score.

CONCLUSION

The M. malabathricum leaves showed antiulcer activity, which could be attributed to their antioxidant and anti-inflammatory activities. This requires further in-depth studies.