A Rare Case of Pulmonary Carcinosarcoma with Unusual Presentation: A Diagnostic Dilemma

Pulmonary carcinosarcoma is a rare malignancy of the lung and has poor prognosis than non-small cell lung cancer. Effective treatment has not been developed for non-resect able advanced stage. We report a case in a 51-year-old female who presented with a right sided massive pleural effusion. Pleural biopsy tissue histology and immunohistochemistry revealed carcinosarcoma.

Neonatal enthesis healing involves non-inflammatory formation of acellular scar through ECM secretion by resident cells

Wound healing is a well-orchestrated process that typically recruits the immune and vascular systems to restore the structure and function of the injured tissue. Injuries to the enthesis, a hypocellular and avascular tissue, often result in fibrotic scar formation and loss of mechanical properties, thereby severely affecting musculoskeletal function and life quality. This raises questions about the healing capabilities of the enthesis. Here, we established an injury model to the Achilles entheses of neonatal mice to study the possibility that at an early age, the enthesis can heal more effectively. Histology and immunohistochemistry analyses revealed an atypical process that did not involve inflammation or angiogenesis. Instead, neonatal enthesis healing was mediated by secretion of collagen types I and II by resident cells, which formed a permanent hypocellular and avascular scar. Transmission electron microscopy showed that the cellular response to injury, including ER stress, autophagy and cell death, varied between the tendon and cartilage ends of the enthesis. Single-molecule in situ hybridization, immunostaining, and TUNEL assays verified these differences. Finally, gait analysis showed that these processes effectively restored function of the injured leg. Collectively, these findings reveal a novel healing mechanism in neonatal entheses, whereby local ECM secretion by resident cells forms an acellular ECM deposit in the absence of inflammation markers, allowing gait restoration. These insights into the healing mechanism of a complex transitional tissue may lead to new therapeutic strategies for adult enthesis injuries.

Siponimod Inhibits the Formation of Meningeal Ectopic Lymphoid Tissue in Experimental Autoimmune Encephalomyelitis

Background and ObjectivesTo investigate whether the formation or retention of meningeal ectopic lymphoid tissue (mELT) can be inhibited by the sphingosine 1-phosphate receptor 1,5 modulator siponimod (BAF312) in a murine model of multiple sclerosis (MS).MethodsA murine spontaneous chronic experimental autoimmune encephalomyelitis (EAE) model, featuring meningeal inflammatory infiltrates resembling those in MS, was used. To prevent or treat EAE, siponimod was administered daily starting either before EAE onset or at peak of disease. The extent and cellular composition of mELT, the spinal cord parenchyma, and the spleen was assessed by histology and immunohistochemistry.ResultsSiponimod, when applied before disease onset, ameliorated EAE. This effect was also present, although less prominent, when treatment started at peak of disease. Treatment with siponimod resulted in a strong reduction of the extent of mELT in both treatment paradigms. Both B and T cells were diminished in the meningeal compartment.DiscussionBeneficial effects on the disease course correlated with a reduction in mELT, suggesting that inhibition of mELT may be an additional mechanism of action of siponimod in the treatment of EAE. Further studies are needed to establish causality and confirm this observation in MS.

Establishment of a New Cell Line of Canine Mammary Tumor CMT-1026

Canine mammary tumors (CMTs) have histopathological, epidemiologic and clinical characteristics similar to those in humans and are known to be one of the best models for human breast cancer (HBC). This research aimed to describe a newly established canine cell line, CMT-1026. Tumor samples were collected from a female dog exhibiting clinical mammary neoplasm, and the adherent cells were cultured. Both the histology and immunohistochemistry (IHC) of tumor samples were estimated. Cell growth, ultrastructural, cytological and immunocytochemistry (ICC) features of CMT-1026 were examined. CMT-1026 cells were inoculated into 10 female BALB/c nude mice to evaluate oncogenicity and metastatic ability. Hematoxylin-eosin (H.E.) staining of the tumors revealed an epithelial morphology. Electron microscopy was used to detect histological and cytological of smears, and ultrathin sections showed that CMT-1026 cells were polygonal and characterized by atypia and high mitotic index in the tumor, with prominent nucleoli and multinucleated cells. IHC characterization of CMT-1026 indicated ER-, PR-, HER-2, p63+, CK5/6+, and α-SMA+ epithelial cells. ICC characterization of CMT-1026 showed high expression of Claudin-1, Delta-catenin, SOX-2, and KI-67. At 2 weeks after inoculation of the CMT-1026 cells, phyma was found in 100% of the mice. The xenograft cancers showed conservation of the original H.E. features of the female dog cancer. In conclusion, CMT-1026 may be a model of canine mammary cancer that can be used in research on the pathogenesis of both CMT and HBC.

Immunohistochemical Evaluation of Periodontal Regeneration Using a Porous Collagen Scaffold

(1) Aim: To immunohistochemically evaluate the effect of a volume-stable collagen scaffold (VCMX) on periodontal regeneration. (2) Methods: In eight beagle dogs, acute two-wall intrabony defects were treated with open flap debridement either with VCMX (test) or without (control). After 12 weeks, eight defects out of four animals were processed for paraffin histology and immunohistochemistry. (3) Results: All defects (four test + four control) revealed periodontal regeneration with cementum and bone formation. VCMX remnants were integrated in bone, periodontal ligament (PDL), and cementum. No differences in immunohistochemical labeling patterns were observed between test and control sites. New bone and cementum were labeled for bone sialoprotein, while the regenerated PDL was labeled for periostin and collagen type 1. Cytokeratin-positive epithelial cell rests of Malassez were detected in 50% of the defects. The regenerated PDL demonstrated a larger blood vessel area at the test (14.48% ± 3.52%) than at control sites (8.04% ± 1.85%, p = 0.0007). The number of blood vessels was higher in the regenerated PDL (test + control) compared to the pristine one (p = 0.012). The cell proliferative index was not statistically significantly different in pristine and regenerated PDL. (4) Conclusions: The data suggest a positive effect of VCMX on angiogenesis and an equally high cell turnover in the regenerated and pristine PDL. This VCMX supported periodontal regeneration in intrabony defects.

Fibrous Histiocytoma of Anterior Ethmoidal Sinus: Case Report and Review of the Literature

Benign fibrous histiocytoma of the para nasal sinus is a rare tumor of this region which originates from mesenchymal cells. A 9-year-old girl presented with gradually enlarging mass above the medial canthus over 3 months. Orbital computerized tomography scan showed a round well-differentiated homogeneous mass in the anterior ethmoidal sinus. Histology and immunohistochemistry analysis after excision revealed proliferation of spindle-shaped fibroblasts in storiform pattern and histiocytes without mitosis and anaplasia. After 9 months from surgical excision, recurrence occurred which resulted in total excision again. This is the first reported case of benign fibrous histiocytoma involving the ethmoid sinus in Iranian people. Rare sinus tumor should be considered in the differential diagnosis of sinus tumors.

Snoring as main symptoms of peripheral primitive neuroectodermal tumor in oropharynx:a case report with review of literature

IntroductionIn children, snoring is often associated with hypertrophied tonsils and adenoids. There was a case in a girl who did not suffer from hypertrophy adenoids, but from a peripheral primitive neuroectodermal tumor (pPNET) in the oropharynx. pPNET often occurs in the deep soft tissues of the trunk, paravertebral, lower limbs and retroperitoneum. It is rarely located in children's oropharynx and makes snoring.Patient concernsWe report a case of a 4-years-old girl who complained of slurred speech and snoring. Her serum showed normal results, computed tomography (CT) and magnetic resonance imaging (MRI) revealed a mass lesion in oropharynx. By using histology and immunohistochemistry, cluster of differentiation 99 (CD99), vimentin, friend leukemia integration 1 (FLI-1), integrase interactor-1 and α-smooth muscle actin were positive, but epithelial membrane antigen, erythroblast transformation-specific (ETS) related gene (ERG), NK homeobox 2.2, Wilms’ tumor 1 and S100-protein were negative. And the rearrangement of the Ewing sarcoma breakpoint region 1 (EWSR1) gene was proved in the test of fluorescent.DiagnosisShe was diagnosed as a peripheral primitive neuroectodermal tumor.Interventions and outcomeThe girl had been treated with surgery and chemotherapy. She has been well for 24 months without any signs of disease.ConclusionIn children who snore, we should not only think of hypertrophied adenoids, but also the possibility of pPNETs in oropharynx. CT scan or MRI should be conducted in time, as well as histology and immunohistochemistry to avoid misdiagnosis.

A humanized orthotopic tumor microenvironment alters the bone metastatic tropism of prostate cancer cells

Prostate cancer (PCa) is the second most commonly diagnosed cancer in men, and bone is the most frequent site of metastasis. The tumor microenvironment (TME) impacts tumor growth and metastasis, yet the role of the TME in PCa metastasis to bone is not fully understood. We used a tissue-engineered xenograft approach in NOD-scid IL2Rγnull (NSG) mice to incorporate two levels of humanization; the primary tumor and TME, and the secondary metastatic bone organ. Bioluminescent imaging, histology, and immunohistochemistry were used to study metastasis of human PC-3 and LNCaP PCa cells from the prostate to tissue-engineered bone. Here we show pre-seeding scaffolds with human osteoblasts increases the human cellular and extracellular matrix content of bone constructs, compared to unseeded scaffolds. The humanized prostate TME showed a trend to decrease metastasis of PC-3 PCa cells to the tissue-engineered bone, but did not affect the metastatic potential of PCa cells to the endogenous murine bones or organs. On the other hand, the humanized TME enhanced LNCaP tumor growth and metastasis to humanized and murine bone. Together this demonstrates the importance of the TME in PCa bone tropism, although further investigations are needed to delineate specific roles of the TME components in this context.

Nasal Cavity Schwannoma—A Case Report and Review of the Literature

Schwannomas are rare slow-growing benign tumors arising from Schwann cells lining the nerve sheaths. Head and neck schwannomas account for about one-third of all cases, and only 4% of them arise from the sinonasal tract. Its diagnosis is based on histology and immunohistochemistry. Complete surgical excision is the most recommended treatment option, and endoscopic surgery has been widely performed in recent years. In this study, we presented a case of a 55-year-old female with schwannoma arising from the lateral wall of the nasal cavity, causing epistaxis and rhinorrhea. The patient underwent endoscopic excision with prompt resolution of symptoms. The reported cases of nasal cavity schwannoma were reviewed and summarized for educational purposes.

Retrospective immunohistochemical investigation on dolphin morbillivirus infection by comparing the performance of heterologous monoclonal and polyclonal antibodies – Short communication

Dolphin morbillivirus (DMV) is a pathogen of great concern in free-ranging cetaceans. Confirmation and staging of morbillivirus infections rely on histology and immunohistochemistry (IHC), following molecular detection. As at the present time no specific antibodies (Abs) against DMV are available, two heterologous Abs have been used worldwide for the examinations of morbillivirus infections of cetaceans. One is a monoclonal Ab (MoAb) prepared against the N protein of canine distemper virus (CDV), whereas the other is a polyclonal Ab raised in rabbits against rinderpest virus (RPV). Both Abs are known to show cross-reactivity with DMV. In this study we compared the labelling quality and the neuroanatomical distribution of staining with these two Abs by means of IHC analysis. To this end, serial sections of the target organs from ten free-ranging stranded cetaceans, previously diagnosed as being infected with DMV by PCR and/or serology, were subjected to IHC. The brain, lungs and lymph nodes of one animal were found to be positive with both Abs. From two other animals, the brain and the spleen, respectively, tested positive only with the polyclonal Ab. In the positive brain tissues, multifocal immunostaining was observed, with similar staining location and extent, with the two antibodies tested. Our results suggest that the polyclonal anti-RPV Ab might have a stronger binding activity to DMV than the anti-CDV MoAb. Nevertheless, the elaboration and use of specific anti-DMV Abs might be essential to guarantee conclusive results in diagnostic and pathogenetic investigations.