Desmin expression in rhabdomyosarcoma: influence of the desmin clone and immunohistochemical method

Fetal rhabdomyoma in a Thoroughbred filly

A newborn Thoroughbred filly presented with a large mass located on the ventro-rostral aspect of the mandible. The mass was surgically removed under general anaesthesia. Upon gross examination, the mass was well circumscribed with a heterogeneous lobulated appearance. The results of histopathology and immunohistochemistry were consistent with a diagnosis of congenital fetal rhabdomyoma. On follow-up at six months post-surgical excision, no abnormalities were noted on clinical examination.

Infliximab abrogates adenine-induced chronic kidney disease via modulation of the MAPK/JNK/ASK signaling pathway in rats

Chronic kidney disease (CKD) is a prominent cause of death worldwide. Infliximab is one of the anti-TNF-α; herein, we studied the effect of infliximab on adenine-induced CKD. To inspect the role of infliximab, either ameliorative or curative, on CDK induced with adenine. Thirty Wistar albino rats were separated into five groups of 6 rats' each: rats of group Ι were kept as control given saline, rats of group II were treated with infliximab (5 mg/kg, i.p.) for 5 weeks, rats of group ΙΙΙ (the diseased group) had an adenine containing diet (0.25% W/W in feed) for 5 weeks, rats of group ΙV (the ameliorative group) had an adenine-containing diet and infliximab (5 mg/kg, i.p.) for 5 weeks simultaneously, and rats of group V (the curative group) had adenine containing diet then a single dose of infliximab (5 mg/kg, i.p.) was given in the 6th week. Infliximab treatment revealed a decrease in the plasma levels of urea, creatinine, NGAL, and MDA with a substantial increase in TAC. Also, inflammatory mediators such as IL-6 and NF-κB were significantly decreased with the down-regulation of the ASK1/MAPK/JNK pathway. Caspase 3 was downregulated. Also, infliximab treatment exhibited improvement in the histological and immunohistochemical kidney changes. Through its involvement in reducing oxidative stress, inflammation, and apoptosis, infliximab has an ameliorative and curative effect on CKD induced with adenine.

Promising Antifungal Activity of Encephalartos laurentianus de Wild against Candida albicans Clinical Isolates: In Vitro and In Vivo Effects on Renal Cortex of Adult Albino Rats

Candida albicans can cause various infections, especially in immunocompromised patients. Its ability to develop resistance to the current antifungal drugs as well as its multiple virulence factors have rendered the problem even more complicated. Thus, in the present investigation, we elucidated an in vitro and in vivo antifungal activity of Encephalartos laurentianus methanol extract (ELME) against C. albicans clinical isolates for the first time. A phytochemical identification of 64 compounds was conducted in ELME using LC-MS/MS. Interestingly, ELME exhibited antifungal activity with MIC values that ranged from 32–256 µg/mL. Furthermore, we investigated the antibiofilm activity of ELME against the biofilms formed by C. albicans isolates. ELME displayed antibiofilm activity using a crystal violet assay as it decreased the percentages of cells, moderately and strongly forming biofilms from 62.5% to 25%. Moreover, the antibiofilm impact of ELME was elucidated using SEM and fluorescent microscope. A significant reduction in the biofilm formation by C. albicans isolates was observed. In addition, we observed that ELME resulted in the downregulation of the biofilm-related tested genes (ALS1, BCR1, PLB2, and SAP5) in 37.5% of the isolates using qRT-PCR. Besides, the in vivo antifungal activity of ELME on the kidney tissues of rats infected with C. albicans was investigated using histological and immunohistochemical studies. ELME was found to protect against C. albicans induced renal damage, decrease desmin and inducible nitric oxide synthase, increase alkaline phosphatase, and increase infected rats’ survival rate. Additionally, the cytotoxicity of ELME was elucidated on Human Skin Fibroblast normal cells using MTT assay. ELME had an IC50 of 31.26 µg/mL. Thus, we can conclude that ELME might be a promising future source for antifungal compounds.

Progesterone Receptor or Cytoskeletal Protein?

Immunoblotting is used to characterize the various nuclear progesterone receptor (nPR) isoforms present in tissues; however, the success of this technique is dependent on the specificity of the primary nPR antibody. The authors investigate the specificity of a frequently used nPR antibody, sc-538, in total protein from human myometrium and a myometrial cell line (PHM1-31). Using immunoblotting, 2 sc-538 immunoreactive bands at 100 and 55 kDa were detected. The bands were extracted and identified by 1-dimensional liquid chromatography mass spectrometry. The predominant protein in the 100-kDa band was alpha-actinin. The dominant proteins in the smaller band were vimentin (57 kDa) and desmin (53 kDa). Myometrial lysate was immunoprecipitated with sc-538, and immunoblotting of the immunoprecipitate with antibodies to alpha-actinin, desmin, and vimentin confirmed the presence of these proteins. The sc-538 nPR antibody therefore cross-reacts with cytoskeletal proteins that could be misinterpreted as nPR isoforms. Such misinterpretation has confused the progesterone response literature.

VEGF is an important mediator of tumor angiogenesis in malignant lesions in a genetically engineered mouse model of lung adenocarcinoma

Background

VEGF is one of the key drivers of physiological or pathological angiogenesis hence several VEGF inhibitors are in different stages of clinical development. To further dissect the role of VEGF in different stages of tumor progression in lung tumors, we utilized Kras^G12D-LSL GEMMs (genetically engineered mouse models).

Methods

Intranasal delivery of adenoviruses expressing cre recombinase in Kras^G12D-LSL mice results in the expression of mutant Kras that leads to development of tumor lesions ranging from adenomatous hyperplasia to large adenoma and adenocarcinoma over time in lung. In the current study, we treated Kras^G12D-LSL mice at 14 weeks post inhalation with three different angiogenic inhibitors including axitinib and PF-00337210 both of which are selective inhibitors of VEGFR and sunitinib which targets VEGFR, C-SF1-R, PDGFR and KIT.

Results

Pathology findings showed no significant difference in percentage of adenomatous hyperplastic lesions between the vehicle vs. any of the treatments suggesting that angiogenesis may not play a major role at early stages of tumorigenesis. However, each inhibitor suppressed percentage of benign adenoma lesions and almost fully inhibited growth of adenocarcinoma lesions in the recipients which was consistent with a reduction in tumor vasculature. Treatment with sunitinib which is a multi-targeted RTKI did not provide any advantage compared to selective VEGFR inhibitor further emphasizing role of VEGF in tumor angiogenesis in this model.

Conclusion

Overall, our studies indicate significance of VEGF and angiogenesis in a spontaneous model of lung tumorigenesis and provide a proof of mechanism for anti-cancer activity of VEGF inhibitors in this model.

The decreased metastatic potential of rhabdomyosarcoma cells obtained through MET receptor downregulation and the induction of differentiation

Rhabdomyosarcoma (RMS) is the most common type of pediatric soft tissue sarcoma. The MET receptor has an important role in the biology of RMS, and its overexpression and hyperactivation correlate with the metastatic ability of RMS. Consequently, interfering with MET expression or functionality may constitute a sound strategy for reducing the progression and metastatic potential of RMS. Our study reveals that downregulation of the MET receptor leads to changes in the morphology of ARMS cell in vivo. Tumors acquire a spindle shape that is characteristic of muscle fibers. Inhibition of MET expression or function leads to (i) a decreased expression of the early myogenic marker MyoD, (ii) a decreased ability of ARMS cells to metastasize to bone marrow cavities, (iii) downregulation of CXCR4 receptor expression and (iv) a decreased migration of MET-depleted cells towards gradients of HGF and SDF-1. Finally, we demonstrate that in vitro differentiation of alveolar RMS cells decreases their metastatic behavior by reducing both the expression of the MET and CXCR4 receptors and their migratory response to HGF and SDF-1. These findings suggest that blockers of MET receptor function and inducers of RMS cells differentiation may be clinically useful for reducing the aggressiveness and metastatic potential of RMS and may have significant implications for its treatment.

Desmin detection in FNAB samples of rhabdomyosarcoma: an immunocytochemical study

We performed immunocytochemical (ICC) staining for desmin on 65 fine needle aspiration biopsies from 45 patients with rhabdomyosarcoma, using the avidin-biotin-peroxidase complex method (ABC), and two types of antibodies, D33 and DE-R-11. The material was fixed either in ether-alcohol or in Delaunay's solution. The ABC method was applied to Papanicolaou stained slides, without destaining. We compared the quality of staining on fresh, routinely prepared slides vs archival material and the quality of staining on smears vs cytospins. In 20 cases, D33 and DE-R-II were applied to a pair of slides from the same tumour sample in order to see if there was any difference in their ability to recognize desmin. Desmin was positive in all 18 cases in which ICC staining was performed at the same time diagnoses were given. Among the 27 cases where ICC staining was carried out on archival material, seven were negative. Slides from four of these cases were 20 or more years old and negative reaction could be attributed to heating of slides before coversliping and/or to uneven distribution of desmin immunoreactivity in tumours. The second reason was probably the cause of negative reactions in cases from 1985 and 87. The type of slide preparation had no influence on the quality of staining. However, results were easier to read on cytospins because cells were more evenly distributed. Finally, our results proved that there was no significant difference between D33 and DE-R-11 in their ability to recognize desmin.

Immunohistochemistry of neuron-specific enolase in neurons of the medulla oblongata from human autopsies

Neuron-specific enolase (NSE) is a glycolytic enzyme specifically expressed in neurons. NSE has been used as a marker for neuronal damage in brain injury. We studied the immunohistochemical localization of this enzyme in the medulla oblongata obtained from human forensic autopsy specimens. Neurons in the dorsal motor nucleus of vagal nerve expressed statistically significantly less NSE immunoreactivity in the cytoplasm than in the hypoglossal nucleus (XII), solitary nucleus, spinal trigeminal nucleus, and lateral cuneate nucleus. Cases of carbon monoxide intoxication by burning showed a higher incidence of NSE immunoreactivity in the cell nucleus of the XII than other cases, while there was no statistically significant correlation between NSE immunoreactivity in the cell nucleus and the Nissl amount. This indicates that the accumulation of NSE immunoreactivity in the cell nucleus might be a vital reaction rather than a postmortem artifact.

Immunohistochemical study of neuron-specific enolase in human brains from forensic autopsies

Immunohistochemistry using anti-human neuron-specific enolase (NSE) mouse monoclonal antibody was performed in human brains from autopsy cases, which enabled us to assess the neuronal damage besides hematoxylin and eosin or Klüver-Barrera stain. Neurons in cerebral neocortex which showed necrotic changes such as prominent cytoplasmic vacuolization or cellular shrinkage with nuclear pyknosis showed a tendency to be less stained by anti-NSE antibody. Anti-NSE immunostaining was statistically significantly less in the neocortex from CO intoxication than from other causes of death, although morphological necrotic changes were less observed in CO intoxication. Hippocampal CA1 neurons clearly lost NSE immunoreactivity with the progression of necrotic changes. Neurons in CA2 were statistically significantly better stained by anti-NSE antibody than in CA1, 3, and 4. Cerebellar Purkinje cells were poorly stained by anti-NSE antibody, whereas neurons in cerebellar dentate nucleus and inferior olive in medulla oblongata were better stained. Anti-NSE immunostaining was lost in the injured areas of the cerebral neocortex while neurons in the intact areas were better stained in brain injury. These results indicate that anti-NSE immunostaining of neurons could reflect vital reaction and could be useful in evaluating neuronal damage in the hippocampal CA1 region or brain injury.