Vimentin Immunoreactivity Research Articles

Pathomorphological and Immunohistochemical Study of Fibrosarcoma in an Adult Dog: A Case Report

Aim: The objective of the present case report is to describe pathomorphological findings and immunohistochemical expression of pancytokeratin (PCK), vimentin, proliferating cell nuclear antigen (PCNA) and Ki67 in a case of fibrosarcoma in dog. Case Presentation: A large, round ball-like growth of approximately 14 centimetres in diameter was noticed on caudal aspect of left thigh region in ten years old male bull dog. Its surface was ulcerated. It was soft in consistency and cut surface appeared pinkish-white. Giemsa-stained smears revealed spindle cells with elongated nuclei containing granular chromatin, single to multiple nucleoli and scanty cytoplasm. Histopathological examination revealed moderately to well-differentiated neoplastic fibroblasts arranged in interwoven pattern with the presence of collagenous stroma. Neoplastic cells were characterized by pleomorphic, oval to elongated nuclei with single to multiple prominent nucleoli and moderate to scanty cytoplasm. Mitotic count was 1.2/high power field. The Immunohistochemical staining revealed intracytoplasmic positive immunoreactivity for vimentin and no immunoreactivity for PCK. Proliferating neoplastic cells revealed mild to strong nuclear immunostaining for PCNA and Ki67 with 56.7% PCNA index and 4.0% Ki67 index. Conclusion: Based on histopathological findings, the case was diagnosed as fibrosarcoma. Immunopositive reactivity for vimentin and no immunoreactivity for PCK indicated the mesenchymal origin of the tumour. Histopathological features, low mitotic count and low Ki67 index suggested the less aggressive behaviour of the tumour in the present case.

Changes in Immunoreactivity of Vimentin and GFAP in the Hippocampus of Patients with Drug-Resistant Epilepsy

Epilepsy is a serious neurological disorder that can greatly impact a person’s quality of life and even result in disability. Unfortunately, despite the use of various antiepileptic drugs, more than 30% of patients develop a form of the disease that is resistant to medication, leaving surgery as the only treatment option. In order to better understand and potentially treat epilepsy, there has been a focus on the role of glial mechanisms and the potential for pathogenetic treatment. Specifically, researchers have looked at the expression of cytoskeletal proteins, such as Glial Fibrillary Acidic Protein (GFAP) and vimentin, in nervous tissue. Our study examined the expression of these proteins in the hippocampus of patients with different types of hippocampal sclerosis and Drug-Resistant Epilepsy (DRE). We found a significant increase in the expression of GFAP and vimentin in these structures, suggesting a potential role in the development of reactive gliosis. However, we did not find any correlations between these proteins in all areas studied. This suggests that the activation of these cytoskeletal proteins may occur independently and ultimately contribute to the development of reactive gliosis. These findings provide valuable insights into the mechanisms of epilepsy and may help improve diagnostic and treatment approaches.

The analysis of boric acid effect on epithelial-mesenchymal transition of CD133 + CD117 + lung cancer stem cells.

Targeting lung cancer stem cells (LC-SCs) for metastasis may be an effective strategy against lung cancer. This study is the first on epithelial-mesenchymal transition (EMT) properties of boric acid (BA) in LC-SCs. LC-SCs were isolated using the magnetic cell sorting (MACS) method. Tumor-sphere formation and flow cytometry confirmed CSC phenotype. The cytotoxic effect of BA was measured by MTT analysis, and the effect of BA on EMT was examined by migration analysis. The expression levels of ZEB1, SNAIL1, ITGA5, CDH1, ITGB1, VIM, COL1A1, and LAMA5 genes were analyzed by RT-qPCR. E-cadherin, Collagen-1, MMP-3, and Vimentin expressions were analyzed immunohistochemically. Boric acid slightly reduced the migration of cancer cells. Increased expression of transcription factor SNAIL (p < 0.001), but not ZEB1, was observed in LC-SCs. mRNA expression levels of ITGB1 (p < 0.01), ITGA5 (p < 0.001), COL1A1 (p < 0.001), and LAMA5 (p < 0.001) increased; CDH1 and VIM decreased in LC-SCs. Moreover, while E-cadherin (p < 0.001) and Collagen-1 (p < 0.01) immunoreactivities significantly increased, MMP-3 (p < 0.001) and Vimentin (p < 0.01) immunoreactivities decreased in BA-treated LC-SCs. To conclude, the current study provided insights into the efficacy and effects of BA against LC-SCs regarding proliferation, EMT, and cell death for future studies.

Optic nerve meningioma and cloacal adenocarcinoma in a Humboldt penguin.

A 26-y-old, male, captive Humboldt penguin (Spheniscus humboldti) was euthanized following a 3.5-mo history of weakened elimination mechanics, recurrent tenesmus, intermittent hemorrhagic droppings, and a cloacal mass. Blepharospasm, of unknown cause, of the right eye was present for ~3 mo before euthanasia. Autopsy revealed a cloacal adenocarcinoma with localized coelomic carcinomatosis and distant metastases to the liver and lungs. On histopathology, a 2.6 × 1.2 × 0.5-mm, well-demarcated mass was found surrounding the right optic nerve, expanding the subdural space and wrapping the leptomeninges. The mass was composed of neoplastic spindle-to-polygonal cells consistent with a meningioma, meningothelial subtype. No evidence of neoplasia was found in the optic chiasm or brain, indicating a primary retrobulbar meningioma. Immunohistochemistry for cytokeratin AE1/AE3, vimentin, and S100 revealed robust and consistent immunoreactivity to vimentin, and weak and variable immunoreactivity to cytokeratin and S100, supporting the diagnosis. Meningiomas have been described only rarely in avian species, and we found no reports of optic nerve meningiomas in any avian species to date. The optic nerve meningioma in this case was considered a clinically incidental finding.

Tumor neuroectodérmico primitivo na coluna cervical de um cão - Relato de Caso

ABSTRACT A case of peripheral primitive neuroectodermal tumor in the cervical region of a canine is described. The patient was a canine, male, five years old, large size, with acute neurological clinical signs, severe neck pain and tetraplegia. On computed tomography, an oval-shaped mass located dorsally to cervical vertebrae C4 to C7 was observed, with infiltration over the spinal cord between vertebrae C4 and C5, discreetly widening the dorsal intervertebral foramina of the cervical vertebrae and compressing the dorsal portion of the spinal cord of this segment. Under microscopy, the neoplastic cells were small, irregular in shape and with scarce cytoplasm. Immunoreactivity for vimentin, which can only be expressed in PTNEs tumors, was decisive for diagnostic confirmation. Additionally, the positivity of the S-100 protein, which is expressed in neuroectodermal cells mainly of the neural crest cells, reinforced the classification as PTNE, and the negativity in the expression for glial fibrillary acidic protein (GFAP) ruled out the presence of small cell glioma of the central nervous system. Based on the clinical history, imaging exams, cellular morphology and mainly on immunohistochemical staining, the diagnosis of primitive neuroectodermal tumor (PTNE) with infiltration and compression of the spinal cord in the cervical region of the dog was confirmed, considered uncommon in this species.

Fetal development of the human amygdala.

The intricate development of the human amygdala involves a complex interplay of diverse processes, varying in speed and duration. In humans, transient cytoarchitectural structures deliquesce, leading to the formation of functionally distinct nuclei as a result of multiple interdependent developmental events. This study compares the amygdala's cytoarchitectural development in conjunction with specific antibody reactivity for neuronal, glial, neuropil, and radial glial fibers, synaptic, extracellular matrix, and myelin components in 39 fetal human brains. We recognized that the early fetal period, as a continuation of the embryonic period,is still dominated by relatively uniform histogenetic processes. The typical appearance of ovoid cell clusters in the lateral nucleus during midfetal period is most likely associated with the cell migration and axonal growth processes in the developing human brain. Notably, synaptic markers are firstly detected in the corticomedial group of nuclei, while immunoreactivity for the panaxonal neurofilament marker SMI 312 is found dorsally. The late fetal period is characterized by a protracted migration process evidenced by the presence of doublecortin and SOX-2 immunoreactivity ventrally, in the prospective paralaminar nucleus, reinforced by vimentin immunoreactivity in the last remaining radial glial fibers. Nearing the term period, SMI 99 immunoreactivity indicates that perinatal myelination becomes prominent primarily along major axonal pathways, laying the foundation for more pronounced functional maturation. This study comprehensively elucidates the rate and sequence of maturational events in the amygdala, highlighting the key role of prenatal development in its behavioral, autonomic, and endocrine regulation, with subsequent implications for both normal functioning and psychiatric disorders.

Immunohistochemical expression of vimentin, E-cadherin, and CD45 in natural cases of canine cutaneous round tumors.

Round cell tumors are common cutaneous lesions in dogs, with increased occurrence percentages among different skin tumors. This study aimed to investigate the frequency as well as gross and pathological characteristics of round cell tumors in natural cases of tumorous dogs in relation to breed, sex, and age. Moreover, it aimed to evaluate the immunohistochemical expression of a panel of immunohistochemical stains, including vimentin, E-cadherin, and cluster of differentiation (CD45) as an adjunct technique for the differential diagnosis of cutaneous round cell neoplasm. Data were collected from 64 dogs of both sexes (36 females and 28 males), various breeds, and different ages (8 months to 7 years). The histopathological nature of neoplastic growth was reported, and neoplasm prevalence was classified using age, sex, breed, and site on the body. We observed 48 cases of transmissible venereal tumors, 12 cutaneous histiocytomas, and 4 histiocytic sarcoma. Immunohistochemical characterization revealed an intense positive immunoreactivity for vimentin in transmissible venereal tumor cells and moderate positive immunoreactivity for E-cadherin and CD45 in cutaneous histiocytoma and histiocytic sarcoma cells. In conclusion, the canine transmissible venereal tumor was the most frequent form of round cell tumor; thus, a definitive cutaneous neoplasm diagnosis should be based on histopathological morphology and immunohistochemical findings.

Astrocyte Reactivity and Neurodegeneration in the Female Rat Brain Following Alcohol Dependence.

Recent evidence suggests that alcohol use disorder (AUD) may manifest itself differently in women compared to men. Women experience AUDs on an accelerated timeline and may have certain regional vulnerabilities. In male rats, neuronal cell death and astrocyte reactivity are noted following induction of alcohol dependence in an animal model of an AUD. However, the regional and temporal patterns of neurodegeneration and astrocyte reactivity have yet to be fully examined in females using this model. Therefore, adult female rats were exposed to a 4-day binge model of alcohol dependence followed by different periods of abstinence. Histological markers for FluoroJade B, a label of degenerating neurons, and vimentin, a marker for reactive astrocytes, were utilized. The expression of these markers in cortical and limbic regions was quantified immediately after their last dose (e.g., T0), or 2, 7, and 14days later. Significant neuronal cell death was noted in the entorhinal cortex and the hippocampus, similar to previous reports in males, but also in several cortical regions not previously observed. Vimentin immunoreactivity was noted in the same regions as previously reported, in addition to three novel regions. Vimentin immunoreactivity also occurred at earlier and later time points in some cortical and hippocampal regions. These data suggest that both neuronal cell death and astrocyte reactivity could be more widespread in females compared to males. Therefore, this study provides a framework for specific regions and time points which should be examined in future studies of alcohol-induced damage that include female rats.

A rare case of pedunculated vulval angiomyofibroblastoma

A rare benign mesenchymal tumour that predominantly occurs in lower genital tract, more frequently vulvo vaginal areas of young to middle-aged women, rarely occurs in retroperitoneum. It needs to be differentiated from other benign conditions like Gartner’s duct cyst, epithelial inclusion cyst, fibroepithelial polyps. It grows more slowly and is non tender, non invasive, and have least tendency for local recurrence. The histologic findings of the tumors are abundant thin-walled blood vessels with hypocellular and hypercellular areas. Almost all tumor cells have immunoreactivity for both desmin and vimentin. It also has estrogen and/or progesterone receptors, but staining for cytokeratin is negative. Here is a case of AMFB of the vulva occurring in a 62-year-old woman, involving the left labia majora. The patient described that her vulva mass grew over few years. The dimension of the tumor was measured as 18*12*4 cms. Excision biopsy done and sent for histopathology.

Usefulness and Limitations of Cryopreservation for Immunocytochemical Staining of Canine Cytological Specimens for Detection of Cytokeratin and Vimentin.

Immunocytochemistry is an advanced diagnostic tool for identifying the origin of tumor cells. This study aimed to highlight the usefulness of cryopreserved, air-dried cytological samples in detecting cytokeratin and vimentin. Air-dried cytological smear samples were prepared from a total of 39 resected canine tumors and stored in a medical freezer without fixation. The duration of cryopreservation ranged from 2 to 56 months. The same tumors were processed for routine histopathological examination. Based on the morphological diagnosis, cryopreserved FNA smears from epithelial tumors were stained by enzymatic immunocytochemistry (ICC) for cytokeratin; those from mesenchymal and melanocytic tumors were stained by ICC for vimentin. To ascertain the positivity of tumor cells to the selected markers, tissue paraffin-embedded sections were also stained by immunohistochemistry (IHC) for the same markers. Immunoreactivity for cytokeratin was detected in cryopreserved cytological smears for a maximum of 46 months. Immunoreactivity for vimentin was clearly detected for 33 months. Smears stored at room temperature for 1 week did not show any signals under immunocytochemical examination. Thus, immunocytochemistry for cytokeratin and vimentin can be safely applied to air-dried smears cryopreserved in a freezer for at least 33 months.

A Scalp Metastatic Follicular Thyroid Carcinoma with a Silent Thyroid History and Normal Thyroid Uptake by PET-CT

Abstract Introduction/Objective Follicular thyroid carcinoma (FTC) accounts for 10%-15% of all primary thyroid cancers. Follicular thyroid cancer is known to metastasize hematogenously, with distant metastasis occurring in 6-20% of cases. Scalp metastasis with an underlying thyroid carcinoma is an exceedingly rare clinical entity; there are less than 15 case reports in the literature. 1-2. Here, we present a case of widely invasive FTC with skull metastases located on the parietal calvarium. The scalp mass was confirmed as follicular thyroid carcinoma via microscopic morphology and positive immunoreactivity for Vimentin, TTF1, thyroglobulin, and PAX8. We present this case not only because of the diagnostic challenge and rare scalp metastasis, but also because of the patient’s unusual “silent” thyroid medical history and no abnormal thyroid uptake by PET-CT. Methods/Case Report 81-year-old female presenting 2-year history of right parietal scalp mass, which was previously suspected for lipoma with attempted resection in Mexico but interrupted due to severe hemorrhage. No palpable thyroid nodule was noted. PET-CT showed avid lesions of the right breast with nipple retraction, as well as avid suspicious lesions of bilateral lungs, calvarium, xiphoid process, right acetabulum, T spine most c/f widely metastatic cancer, most likely a breast primary; evaluation of the neck demonstrates physiologic FDG-activity in the thyroid. Thyroid studies showed hyperthyroidism: TSH (L) &amp;lt;0.010 uIU/mL; Free T3 (H) 4.7 pg/mL and Free T4 1.00 ng/d. The patient was performed Ultrasound-guided FNA and core biopsy of the large parietal scalp lesion, however, FNA of the cystic component was nondiagnostic (no malignant cells seen). Results (if a Case Study enter NA) NA. Conclusion Core biopsy of the large parietal mass the tumor cells tend to form follicular or microfollicular architecture with colloid present, but no papillary nuclear features. Rare mitotic figures are seen. IHC stain of tumor cells are positive for AE1/AE3, Cam5.2, CK7, TTF1, thyroglobulin, PAX8, and Vimentin, which show strong evidence for metastatic follicular thyroid carcinoma (FTC) origin. Tumor cells are negative for Napsin-A, P63, Synaptophysin, Ck5/6, Ck20, EMA, WT1, CDX2, GATA3, Mammaglobin, ER, PR, and BRST2, which helps rule out the primary malignancy from lung, breast, neuroendocrine or other adenocarcinomas.

What is your diagnosis? Ovarian mass in a mare.

What is your diagnosis? Ovarian mass in a mare.

Vimentin and Ki-67 immunolabeling in canine gastric carcinomas and their prognostic value.

This study evaluated the expression of vimentin and Ki-67 proliferative index (PI) by immunohistochemistry in 30 canine gastric carcinomas (GCs) and a possible association with clinical and pathological features and patient's survival time. Vimentin immunoreactivity was assessed in neoplastic cells (in primary lesions, emboli, and metastases) and tumor-associated stroma (TAS) of canine GCs. Ki-67 PI was quantified in the neoplastic epithelial component. Vimentin immunolabeling in neoplastic cells was found in 30% of the primary lesions, in 82% of the neoplastic emboli, and in 50% of the metastases; in TAS, it was observed in all cases. A mean of 16% of the TAS was immunolabeled for vimentin. High vimentin immunolabeling in the TAS (>16%) was detected in 40% of cases. The average value of Ki-67 PI was 50%, and 80% of the lesions had Ki-67 PI above 20%. Vimentin immunolabeling in neoplastic cells was more frequent in less-differentiated carcinomas (diffuse [29%] and indeterminate types [75%]) than well-differentiated carcinomas (intestinal type [0%], P = .049). No significant differences were observed in vimentin immunolabeling in the TAS or Ki-67 PI according to histological diagnosis, depth of invasion, presence of neoplastic emboli or metastases. However, vimentin immunolabeling in the TAS was positively correlated with Ki-67 PI (r = .394, P = .031). Furthermore, a moderate negative correlation was observed between Ki-67 PI and survival time (r = -0.540). Our results suggest that vimentin and Ki-67 PI have potential for providing prognostic information in cases of canine GCs.

Immunolocalization of intermediate filaments in the kidney of the dromedary camel (Camelus dromedarius)

Intermediate filaments belong to a large family of proteins which contribute to the formation of the cytoskeleton. The immunolocalization of cytoskeletal proteins has been used extensively in the diagnosis of various renal pathologies. The present study described the immunolocalization of the cytoskeletal proteins vimentin, desmin, smooth muscle actin, and cytokeratin 19 in the normal kidney of the dromedary camel. Kidney samples from eight adult camels were processed for histology and immunohistochemistry. The kidney was enclosed in a renal capsule composed of vimentin immunoreactive fibroblasts and smooth muscle actin immunoreactive smooth muscle cells. The smooth muscle cells in the renal capsule did not exhibit desmin immunoreactivity. Podocytes forming the visceral layer of the glomerular capsule were immunoreactive for vimentin. Immunoreactivity for vimentin and smooth muscle actin in the parietal layer of the glomerular capsule varied, with both reactive and non-reactive cells observed. Intraglomerular mesangial cells were immunoreactive for smooth muscle actin and desmin, but non-reactive to vimentin. The endothelial lining of blood vessels was vimentin immunoreactive, while smooth muscle actin and desmin were demonstrated in the smooth muscle cells of the vessels. The thin limbs of the loops of Henle in cortical nephrons displayed vimentin immunoreactivity. The proximal and distal convoluted tubules, as well as the collecting ducts were negative to vimentin, smooth muscle actin, desmin and cytokeratin 19 immunostaining. In conclusion, the present study has revealed that similarities and differences exist in the immunolocalization of cytoskeletal proteins in the camel when compared to other mammals. The presence of smooth muscle actin in the parietal cells of the glomerular capsule suggests a contractile function of these cells. The results of the study indicate that vimentin and smooth muscle actin can be used as markers for the identification of podocytes and intraglomerular mesangial cells, respectively, in the camel kidney.

Subcutaneous nodular fasciitis in dogs: Two cases

Nodular fasciitis is a commonly diagnosed condition in humans with rare occurrences in veterinary practice, especially in dogs and cats, where it is usually associated with the ocular region. Two dogs separately had a mass on the shoulder girdle and the caudal part of the elbow of their respective right forelimbs upon presentation for clinical attention in two private veterinary clinics in Abuja, Nigeria. These solitary and well-demarcated masses were characterized by fibroblastic and vascular proliferation along with focal hemorrhage, mononuclear cellular infiltration, and fatty degenerative changes. Nevertheless, histomorphological lesions and positive immunoreactivity for vimentin, α-SMA, and desmin, as well as negative CD31, CD34, and CD117 immunoreactivity led to a definitive diagnosis of nodular fasciitis. This is a novel report of histomorphological and immunohistochemical diagnosis of subcutaneous nodular fasciitis on the right shoulder girdle and elbow regions of dogs in veterinary practice.

Cell surface detection of vimentin, ACE2 and SARS-CoV-2 Spike proteins reveals selective colocalization at primary cilia

The SARS-CoV-2 Spike protein mediates docking of the virus onto cells prior to viral invasion. Several cellular receptors facilitate SARS-CoV-2 Spike docking at the cell surface, of which ACE2 plays a key role in many cell types. The intermediate filament protein vimentin has been reported to be present at the surface of certain cells and act as a co-receptor for several viruses; furthermore, its potential involvement in interactions with Spike proteins has been proposed. Nevertheless, the potential colocalization of vimentin with Spike and its receptors on the cell surface has not been explored. Here we have assessed the binding of Spike protein constructs to several cell types. Incubation of cells with tagged Spike S or Spike S1 subunit led to discrete dotted patterns at the cell surface, which consistently colocalized with endogenous ACE2, but sparsely with a lipid raft marker. Vimentin immunoreactivity mostly appeared as spots or patches unevenly distributed at the surface of diverse cell types. Of note, vimentin could also be detected in extracellular particles and in the cytoplasm underlying areas of compromised plasma membrane. Interestingly, although overall colocalization of vimentin-positive spots with ACE2 or Spike was moderate, a selective enrichment of the three proteins was detected at elongated structures, positive for acetylated tubulin and ARL13B. These structures, consistent with primary cilia, concentrated Spike binding at the top of the cells. Our results suggest that a vimentin-Spike interaction could occur at selective locations of the cell surface, including ciliated structures, which can act as platforms for SARS-CoV-2 docking.

Immunohistochemical features of cells in peripheral microcystoid retinal degeneration

Peripheral microcystoid retinal degeneration (PMD) is an age-related, benign condition in which the peripheral retina develops small holes and undergoes cystic degeneration. This paper demonstrates neuronal alterations in PMD, as studied by immunohistochemistry in postmortem donor eyes (age: 76–89 years; N = 6 donors). In all cases, the degeneration was located in the inferior temporal quadrant, creating holes in the far peripheral retina. There was thinning of the inner retinal layers and the outer plexiform layer (OPL) was patchy or inconspicuous. As a response, Müller cell processes showed increased vimentin immunoreactivity. None of the retinas examined expressed glial fibrillary acidic protein. Cone photoreceptor cells were significantly altered: compared to the adjoining cones that were short, those located in the cystoid retina underwent significant elongation of their inner segments, evident from calbindin immunolabeling, to maintain synaptic contacts with the remnant OPL. The latter consisted of small photoreceptor terminals and scanty processes from shrunken bipolar cells. Besides, cones and ganglion cells undergo oxidative stress, they showed immunoreactivity to 4-hydroxy 2-nonenal and nitrotyrosine. The level of superoxide dismutase-2 was relatively low in the PMD region than in adjacent area, suggesting that the former suffers from oxidative stress.

Vimentin immunoexpression and its prognostic activity in colon cancer among Caucasian patients.

IntroductionIt is generally accepted that colon cancer is the most commonly diagnosed gastrointestinal cancer and a major public health problem. As revealed by studies, the clinical outcomes of patients, especially those with lymph node-positive status, are still unsatisfactory.AimThe current study investigated the expression of vimentin protein in colon adenocarcinoma samples from proximal and distal parts of the colon to assess its prognostic significance by correlating its immunohistochemical expression with the clinicopathological variables and survival of Caucasian patients.Material and methodsTo investigate the clinicopathological and prognostic roles of vimentin expression, the immunohistochemical analysis was performed in colon cancer tumour samples and adjacent non- pathological mucosa. As revealed, the level of vimentin immunohistochemical reactivity correlated with the grade of the histological differentiation (H [2.97] = 37.949; p < 0.001).ResultsThe Kaplan-Meier survival analysis showed that the overall survival rate in the group of patients with low vimentin immunoreactivity was significantly greater than that for patients with a moderate or strong level of vimentin protein expression. Multivariate analysis demonstrated that the grade of tumour differentiation (HR = 2.150; 95% CI: 1.380–3.349, p = 0.001) and vimentin expression (HR = 3.901; 95% CI: 2.436–6.247, p < 0.001) were independent risk factors for worse survival.

MicroRNA-21 expression, serum tumor markers, and immunohistochemistry in canine mammary tumors.

Canine mammary tumors (CMTs) are one of the most common malignancies in dogs and are associated with significant mortality. Serum tumor markers and non-coding microRNAs have gained widespread popularity in human oncology studies. The present study has two aims, first one is to investigate the miR-21 expression compared with changes in serum tumor markers (CEA and CA15-3) in CMT. The second aim is to detect the immunohistochemistry markers as vimentin, P63, and -SMA in CMT. This study enrolled 17 female dogs: 10 with mammary tumors and seven controls without tumors. Blood samples were collected to measure miR-21, CEA, and CA 15-3, and histological samples were prepared for histological grading and immunohistochemistry. CA 15-3 was elevated in all animals, whereas CEA levels showed no change compared with controls. miR-21 was upregulated 12.84-fold in animals with CMT. The most frequently recorded CMT was the mixed type. Myoepithelial cells were identified by P63 immunoreactivity, but not SMA. High expression of miR-21 was observed with positive vimentin immunoreactivity, indicating the mesenchymal origin of the tumor cells. The present study showed that miR-21 was elevated to a greater extent than CA 15-3 (12.84-fold vs. threefold). Tumors that was positive for vimentin immunoreactivity was also associated with an elevation in the levels of miR-21, showing that miR-21 is released from mesenchymal cells. These findings support the hypothesis that miR-21 may be a more sensitive, noninvasive indicator for CMT.

Conjunctival Myxoma: High-Resolution Optical Coherence Tomography Findings of a Rare Tumor

The purpose of this study was to describe 2 cases of biopsy-proven conjunctival myxomas and present their optical signs on high-resolution optical coherence tomography (HR-OCT) with clinical and histopathological correlations. Two middle-aged female patients with a clinical diagnosis of conjunctival cysts were referred for surgical treatment. Clinical assessment, photographs, ultrasound biomicroscopy, and HR-OCT images were obtained. Excisional biopsies were performed, and specimens were sent for histopathological and immunohistochemical analyses. Clinically, these patients presented with a well-circumscribed, semitranslucent, yellow-pinkish mass. Ultrasound biomicroscopy showed a dome-shaped epibulbar mass with medium-to-high internal reflectivity. No compromise of the underlying sclera was noted. HR-OCT showed a normal conjunctival epithelium, a subepithelial nonhomogeneous mass with hyperreflective and hyporeflective areas lined by a highly hyperreflective band, and mild posterior shadowing. Histopathological findings and immunoreactivity for CD34 and vimentin confirmed the diagnosis of conjunctival myxoma. The HR-OCT optical signs found in our 2 cases strongly correlated with the microscopic findings. Disclosing the optical signs observed on HR-OCT can help clinicians diagnose and differentiate this lesion, guiding its management. However, more studies with a larger number of patients comparing conjunctival myxoma and other ocular surface tumors are needed to enlighten readers about the unique pattern observed by HR-OCT.