Liposome co-incubation with cancer cells secreted exosomes (extracellular vesicles) with different proteins expressions and different uptake pathways

We recently showed that in vitro incubation of cells with liposomes of varying compositions can increase exosome secretion and increase the yield of harvested exosomes (extracellular vesicles, EVs). This might foster their potential therapeutic implementations. In the current study, we investigated the surface proteins and the uptake of the harvested exosomes (EVs) to see if the incubation of cells with liposomes would change the biological properties of these exosomes (EVs). Interestingly, exosomes (EVs) induced by solid cationic liposomes lacked some major exosome marker proteins such as CD9, flotillin-1, annexin-A2 and EGF, and subsequently had lower levels of cellular uptake upon re-incubation with donor cancer cells. However, exosomes (EVs) induced under normal condition and by fluid cationic liposomes, displayed the entire spectrum of proteins, and exhibited higher uptake by the donor cancer cells. Although endocytosis was the major uptake pathway of exosomes (EVs) by tumor cells, endocytosis could occur via more than one mechanism. Higher exosome uptake was observed in donor B16BL6 cells than in allogeneic C26 cells, indicating that donor cells might interact specifically with their exosomes (EVs) and avidly internalize them. Taken together, these results suggest a technique for controlling the characteristics of secreted exosomes (EVs) by incubating donor cancer cells with liposomes of varying physiochemical properties

Cyclooxygenase-2 is Involved in the Progression of Thyroid Cancer

Although the inducible form of cyclooxygenase (COX), COX-2, is highly expressed in various cancers and it is also involved in cancer progression, its role in thyroid cancer is not fully understood. We assessed in the situ cyclooxygenase expression in normal thyroids (n=6), Graves\u27 thyroids (n=6), thyroid adenomas (n=12), thyroid follicular (n=15) and papillary carcinomas (n=30). In comparison to the constitutive expression of COX-1, COX-2 was highly expressed in thyroid cancers (90.0% of thyroid papillary carcinomas and 73.3% of thyroid follicular carcinomas) and moderately in thyroid adenomas (25.5%), but barely expressed in normal and Graves\u27 thyroid tissues. This quantitative assessment employed immunohistochemical methods. Thereafter we compared the effect of COX-2 inhibition on a human follicular thyroid carcinoma cell line (WRO), and a human papillary carcinoma cell line (NPA), using selective COX-2 inhibitor(NS-398). The treatment with 50 μM NS-398 suppressed the growth of the COX-2 expressing cells, NPA cells (37.7%;p<0.01) and WRO cells (10.1%;p<0.05). Moreover, at concentrations ? 100 μM, NS-398 induced cell death a mitochondrial dysfunction. In addition, 50 μM of NS-398 inhibited the activation of extracellular signal-regulated kinase in NPA cells after the stimulation with fetal bovine serum. Our results indicate that COX-2 is involved in the progression of thyroid cancer

A case of compressive optic neuropathy putatively caused by IgG4-related idiopathic orbital inflammation.

We report the case of a 58-year-old male presenting with an impairment of the left-sided visual acuity caused by compressiveoptic neuropathy, and marked bilateral proptosis. Blood test showed markedly elevated IgG4 (1830 mg/dl) and positiveTSH receptor-stimulating antibodies (200%), but the thyroid function test were normal. Orbital MRI revealed abnormal soft tissueproliferation around the optic nerve and fusiform enlargement of the extraocular muscles. Systemic CT analysis detectedmultiple lymph node swelling, pseudotumor in the lung, retroperitoneal fibrosis, and kidney lesions. We considered that the eyemanifestation was most likely caused by IgG4-related idiopathic orbital inflammation. Systemic administration of a moderatedose of prednisolone dramatically improved the compression of the optic nerve, as shown by the improvement of the visualacuity and the MRI findings. The clinical course made thyroid-associated ophthalmopathy unlikely. In conclusion, an overallconsideration of the clinical picture and extensive work-up of any possible differential diagnosis including measurement of theserum levels of IgG4 was highly useful in making the diagnosis of the patient

Periostin Promotes Tumor Lymphangiogenesis

Background: Metastasis to regional lymph nodes via lymphatic vessels plays a key role in cancer progression. Tumor lymphangiogenesis is known to promote lymphatic metastasis, and vascular endothelial growth factor C (VEGF-C) is a critical activator of tumor lymphangiogenesis during the process of metastasis. We previously identified periostin as an invasion- and angiogenesis-promoting factor in head and neck squamous cell carcinoma (HNSCC). In this study, we discovered a novel role for periostin in tumor lymphangiogenesis. Methods and Findings: Periostin overexpression upregulated VEGF-C mRNA expression in HNSCC cells. By using conditioned media from periostin-overexpressing HNSCC cells, we examined tube formation of lymphatic endothelial cells. Conditioned media from periostin-overexpressing cells promoted tube formation. To know the correlation between periostin and VEGF-C, we compared Periostin expression with VEGF-C expression in 54 HNSCC cases by immunohistochemistry. Periostin expression was correlated well with VEGF-C expression in HNSCC cases. Moreover, correlation between periostin and VEGF-C secretion was observed in serum from HNSCC patients. Interestingly, periostin itself promoted tube formation of lymphatic endothelial cells independently of VEGF-C. Periostin-promoted lymphangiogenesis was mediated by Src and Akt activity. Indeed possible correlation between periostin and lymphatic status in periostin-overexpressing xenograft tumors and HNSCC cases was observed. Conclusions: Our findings suggest that periostin itself as well as periostin-induced upregulation of VEGF-C may promote lymphangiogenesis. We suggest that periostin may be a marker for prediction of malignant behaviors in HNSCC and a potential target for future therapeutic intervention to obstruct tumoral lymphatic invasion and lymphangiogenesis in HNSCC patients

Graves\u27 disease complicated by ventricular fibrillation in three men who were smokers.

Thyrotoxicosis is known to be associated with sinus tachycardia and supraventricular tachyarrhythmias, but rarely with ventricular fibrillation (Vf), which has only occurred in some patients with hypokalemic periodic paralysis or ischemic heart disease. PATIENT FINDINGS: We present three men who were transferred to our hospital with Graves\u27 disease who developed idiopathic Vf. None of them had hypokalemic periodic paralysis or ischemic heart disease but all were smokers. None of other patients with thyrotoxicosis (587 females and 155 males) who were seen at our hospital, in the period during which the three men were seen, had idiopathic Vf. In our three men with thyrotoxicosis and idiopathic Vf, there was no identifiable underlying heart disease. One of the three patients died of hypoxic encephalopathy. The other two men did not have recurrent Vf after their thyroid function normalized

Ameloblastin induces tumor suppressive phenotype and enhances chemosensitivity to doxorubicin via Src-Stat3 inactivation in osteosarcoma

Ameloblastin (AMBN), the most abundant non-amelogenin enamel matrix protein, plays a role in ameloblast differentiation. Previously, we found that AMBN promoted osteogenic differentiation via the interaction between CD63 and integrin β1, leading to the inactivation of Src; however, how AMBN affects the malignant behavior of osteosarcoma is still unclear. Osteosarcoma affects the bone and is associated with poor prognosis because of the high rate of pulmonary metastases and drug resistance. Here we demonstrated that stable overexpression of AMBN induced apoptosis and suppressed colony formation and cell migration via the inactivation of Src-Stat3 pathway in human osteosarcoma cells. Moreover, AMBN induced chemosensitivity to doxorubicin. Thus, AMBN induced a tumor suppressive phenotype and chemosensitivity to doxorubicin via the AMBN-Src-Stat3 axis in osteosarcoma. Indeed, immunohistochemical expression of AMBN was significantly correlated with better outcome of osteosarcoma patients. Our findings suggest that AMBN can be a new prognostic marker and therapeutic target for osteosarcoma combined with conventional doxorubicin treatment

Risk for Progression to Overt Hypothyroidism in an Elderly Japanese Population with Subclinical Hypothyroidism

Background: Few population-based studies report the changes with time in thyroid function tests in patients with subclinical hypothyroidism. We compared the risk for developing overt hypothyroidism in patients with subclinical hypothyroidism and euthyroid controls from the same population of elderly Japanese. We also sought associations of selected parameters with the development of overt hypothyroidism in the subclinical hypothyroid and euthyroid groups. Methods: We measured thyrotropin (TSH) and free thyroxine (T4) levels at baseline examinations performed from 2000 to 2003 in the cohort of Japanese atomic-bomb survivors and identified 71 patients with spontaneous subclinical hypothyroidism (normal free T4 and TSH >4.5 mIU/L without a history of thyroid treatment, mean age 70 year) and 562 euthyroid controls. We re-examined TSH and free T4 levels an average of 4.2 years later (range, 1.9-6.9). Results: The risk for progression to overt hypothyroidism was significantly increased in subclinical hypothyroid patients (7.0%) compared with control subjects (1.6%) after adjusting for age and sex (odds ratio, 4.56; p=0.009). Higher baseline TSH levels were associated with progression from subclinical to overt hypothyroidism (p=0.02) in the multivariate analysis, including age, sex, antithyroid peroxidase antibody, and ultrasonography (US) findings. The analysis using binary TSH data suggested that a TSH level >8 mIU/L was a predictive value for development of overt hypothyroidism (p=0.005). On the other hand, serum TSH levels spontaneously normalized in 38 (53.5%) of the patients with subclinical hypothyroidism. In the multivariate analysis, normalization of TSH levels was associated with lower baseline TSH levels (p=0.004) and normal and homogenous thyroid US findings (p=0.04). Atomic-bomb radiation dose was not associated with subclinical hypothyroidism or its course. Conclusions: Subclinical hypothyroidism was four times more likely to be associated with development of overt hypothyroidism than euthyroid controls in the sample population of Japanese elderly. TSH levels in half of the patients normalized spontaneously when assessed after an average follow-up period of 4.2 years. Baseline TSH level and thyroid US findings are potential predictors of future thyroid function in subclinical hypothyroidism

A Case of Mixed Medullary and Follicular Cell Carcinoma of the Thyroid

A medullary thyroid carcinoma is a malignant tumor derived from the C-cells of the thyroid. Despite their distinct embryological origin, medullary thyroid carcinomas are exceptionally accompanied by a tumor derived from the follicular cells; this is defined as mixed medullary and follicular cell carcinoma. There have been controversies regarding the origin of this rare mixed thyroid carcinoma questioning whether or not a mixed carcinoma originates from a common cancer stem cell. We present a case of mixed medullary and follicular cell carcinoma in which two thyroid carcinomas were found intermingled in the thyroid as well as in the metastatic cervical lymph nodes. We examined the tumor by immunostaining with thyroglobulin, calcitonin, and thyroid transcription factor-1, and also reviewed the literature and discuss the origin of this rare mixed thyroid carcinoma