Endothelial cells and epithelial BMP signaling control thyroid folliculogenesis via basement membrane assembly

The thyroid gland is composed of spherical units called the follicles. Follicles are delineated by a monolayer of polarized thyrocytes surrounding the colloidal space, and resting on a basement membrane. Folliculogenesis occurs during embryonic development by reorganization of an unstructured mass of non-polarized cells, but regulatory mechanisms remain largely unknown. Using thyroid-specific VegfaKO and Smad1/5dKO, we show that the absence of endothelial cells or of epithelial BMP signaling prevent follicle formation. Furthermore, these KO thyroids displayed impaired basement membrane assembly. Interestingly, medium conditioned by embryonic endothelial progenitor cells (eEPC) rescues the folliculogenic defects of both KO thyroids. Laminin α1β1γ1, abundantly released by eEPC into the culture medium, is critically required for folliculogenesis. These results indicate that endothelial cells and epithelial BMP signaling promote folliculogenesis via assembly of the basement membrane.(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 201

An Ex vivo Culture System to Study Thyroid Development.

The thyroid is a bilobated endocrine gland localized at the base of the neck, producing the thyroid hormones T3, T4, and calcitonin. T3 and T4 are produced by differentiated thyrocytes, organized in closed spheres called follicles, while calcitonin is synthesized by C-cells, interspersed in between the follicles and a dense network of blood capillaries. Although adult thyroid architecture and functions have been extensively described and studied, the formation of the "angio-follicular" units, the distribution of C-cells in the parenchyma and the paracrine communications between epithelial and endothelial cells is far from being understood. This method describes the sequential steps of mouse embryonic thyroid anlagen dissection and its culture on semiporous filters or on microscopy plastic slides. Within a period of four days, this culture system faithfully recapitulates in vivo thyroid development. Indeed, (i) bilobation of the organ occurs (for e12.5 explants), (ii) thyrocytes precursors organize into follicles and polarize, (iii) thyrocytes and C-cells differentiate, and (iv) endothelial cells present in the microdissected tissue proliferate, migrate into the thyroid lobes, and closely associate with the epithelial cells, as they do in vivo. Thyroid tissues can be obtained from wild type, knockout or fluorescent transgenic embryos. Moreover, explants culture can be manipulated by addition of inhibitors, blocking antibodies, growth factors, or even cells or conditioned medium. Ex vivo development can be analyzed in real-time, or at any time of the culture by immunostaining and RT-qPCR. In conclusion, thyroid explant culture combined with downstream whole-mount or on sections imaging and gene expression profiling provides a powerful system for manipulating and studying morphogenetic and differentiation events of thyroid organogenesis

Validation of housekeeping gene and impact on normalized gene expression in clear cell Renal Cell Carcinoma: critical reassessment of YBX3/ZONAB/CSDA expression.

YBX3/ZONAB/CSDA is an epithelial-specific transcription factor acting in the density-based switch between proliferation and differentiation. Our laboratory reported overexpression of YBX3 in clear cell renal cell carcinoma (ccRCC), as part of a wide study of YBX3 regulation in vitro and in vivo. The preliminary data was limited to 5 cases, of which only 3 could be compared to paired normal tissue, and beta-Actin was used as sole reference to normalize gene expression. We thus decided to re-evaluate YBX3 expression by real-time-PCR in a larger panel of ccRCC samples, and their paired healthy tissue, with special attention on experimental biases such as inter-individual variations, primer specificity, and reference gene for normalization

Reciprocal epithelial: Endothelial paracrine interactions during thyroid development govern follicular organization and C-cells differentiation.

The thyroid is a highly vascularized endocrine gland, displaying a characteristic epithelial organization in closed spheres, called follicles. Here we investigate how endothelial cells are recruited into the developing thyroid and if they control glandular organization as well as thyrocytes and C-cells differentiation. We show that endothelial cells closely surround, and then invade the expanding thyroid epithelial cell mass to become closely associated with nascent polarized follicles. This close and sustained endothelial:epithelial interaction depends on epithelial production of the angiogenic factor, Vascular Endothelial Growth Factor-A (VEGF-A), as its thyroid-specific genetic inactivation reduced the endothelial cell pool of the thyroid by >90%. Vegfa KO also displayed decreased C-cells differentiation and impaired organization of the epithelial cell mass into follicles. We developed an ex vivo model of thyroid explants that faithfully mimicks bilobation of the thyroid anlagen, endothelial and C-cells invasion, folliculogenesis and differentiation. Treatment of thyroid explants at e12.5 with a VEGFR2 inhibitor ablated the endothelial pool and reproduced ex vivo folliculogenesis defects observed in conditional Vegfa KO. In the absence of any blood supply, rescue by embryonic endothelial progenitor cells restored folliculogenesis, accelerated lumen expansion and stimulated calcitonin expression by C-cells. In conclusion, our data demonstrate that, in developing mouse thyroid, epithelial production of VEGF-A is necessary for endothelial cells recruitment and expansion. In turn, endothelial cells control epithelial reorganization in follicles and C-cells differentiation

Safety and efficacy of a single intra-articular injection of a novel enhanced protein solution (JTA-004) compared to hylan G-F 20 in symptomatic knee osteoarthritis: a randomized, double-blind, controlled phase II/III study

Background: New minimally invasive treatments are vital to delay joint replacement surgery in patients with knee osteoarthritis. This study was designed to select the most effective among three formulations of an enhanced protein solution containing clonidine, hyaluronic acid, and human plasma (JTA-004), and compare the safety and efficacy of intra-articular administration of the selected formulation with a reference treatment (hyaluronic acid) in symptomatic knee osteoarthritis patients. Methods: In this two-stage, double-blind, phase II/III study conducted in 12 Belgian centers, 50–79-year-old patients with primary knee osteoarthritis were randomized (1:1:1:1) to receive one dose of one of three JTA-004 formulations (differing in clonidine concentration [50 or 100 μg/ml] and volume [2 or 4 ml]) or the reference treatment (hylan G-F 20). Patients were evaluated using Western Ontario McMaster Universities (WOMAC®) Scores and the Short-Form health survey up to 6 months post-injection (Month 6). Drug consumption and safety were evaluated. Results: Among 164 treated patients, 147 completed the study. The JTA-004 formulation containing 200 μg clonidine and 20 mg hyaluronic acid in 2 ml (JTA-200/2) was selected based on interim results at Month 6. The difference in adjusted mean change in WOMAC Pain Subscale Score from baseline (JTA-200/2 minus reference group) at Month 6 was − 9.49 mm; statistical superiority of JTA-200/2 over the reference was not demonstrated. No statistically significant differences in adjusted mean changes from baseline between JTA-200/2 and reference groups were observed for Pain, Physical Function and Stiffness Subscales WOMAC Scores, Total WOMAC Score, and Well-being Score at any timepoint, although JTA-200/2 induced larger improvements in WOMAC Scores than the reference. Statistically significantly larger improvements in WOMAC Pain Subscale Scores for JTA-004 versus the reference were observed in post-hoc analyses on pooled data from all JTA-004 formulations at Month 6 (p = 0.030) and Month 3 (p = 0.014). All JTA-004 formulations had clinically acceptable safety profiles. Conclusions: This study provided preliminary evidence of the safety of intra-articular injection of JTA-004 in knee osteoarthritis patients. Phase III randomized controlled trials with larger sample sizes are needed to evaluate the efficacy of JTA-004 in knee osteoarthritis. Trial registration: Clinicaltrials.gov/identifier NCT02740231; clinicaltrialsregister.eu/identifier 2015–002117-30. Retrospectively registered 13/4/2016.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Safety and efficacy of a single intraarticular injection of a novel enhanced protein solution (JTA-004) compared to hylan G-F 20 in symptomatic knee osteoarthritis: a randomized, double-blind, controlled phase II/ III study

peer reviewedBackground: New minimally invasive treatments are vital to delay joint replacement surgery in patients with knee osteoarthritis. This study was designed to select the most effective among three formulations of an enhanced protein solution containing clonidine, hyaluronic acid, and human plasma (JTA-004), and compare the safety and efficacy of intra-articular administration of the selected formulation with a reference treatment (hyaluronic acid) in symptomatic knee osteoarthritis patients. Methods: In this two-stage, double-blind, phase II/III study conducted in 12 Belgian centers, 50–79 year-old patients with primary knee osteoarthritis were randomized (1:1:1:1) to receive one dose of one of three JTA 004 formulations (differing in clonidine concentration [50 or 100 μg/ml] and volume [2 or 4 ml]) or the reference treatment (hylan G-F 20). Patients were evaluated using Western Ontario McMaster Universities (WOMAC®) Scores and the Short-Form health survey up to 6 months post-injection (Month 6). Drug consumption and safety were evaluated. Results: Among 164 treated patients, 147 completed the study. The JTA-004 formulation containing 200 μg clonidine and 20 mg hyaluronic acid in 2 ml (JTA-200/2) was selected based on interim results at Month 6. The difference in adjusted mean change in WOMAC Pain Subscale Score from baseline (JTA-200/2 minus reference group) at Month 6 was − 9.49 mm; statistical superiority of JTA-200/2 over the reference was not demonstrated. No statistically significant differences in adjusted mean changes from baseline between JTA-200/2 and reference groups were observed for Pain, Physical Function and Stiffness Subscales WOMAC Scores, Total WOMAC Score, and Well being Score at any timepoint, although JTA-200/2 induced larger improvements in WOMAC Scores than the reference. Statistically significantly larger improvements in WOMAC Pain Subscale Scores for JTA-004 versus the reference were observed in post-hoc analyses on pooled data from all JTA-004 formulations at Month 6 (p = 0.030) and Month 3 (p = 0.014). All JTA-004 formulations had clinically acceptable safety profiles. Conclusions: This study provided preliminary evidence of the safety of intra-articular injection of JTA 004 in knee osteoarthritis patients. Phase III randomized controlled trials with larger sample sizes are needed to evaluate the efficacy of JTA-004 in knee osteoarthritis

599P R-IMMUNE: A phase Ib/II study to evaluate safety and efficacy of atezolizumab combined with radio-chemotherapy in a preoperative setting for patients with locally advanced rectal cancer (LARC)

BACKGROUND : There is a strong rationale to combine radiotherapy with immune checkpoint inhibitors (ICIs). This study evaluates this combination before surgery in locally advanced rectal cancer (LARC). [...

Safety and efficacy of intra-articular injection of JTA-004, a novel viscosupplement, in symptomatic knee osteoarthritis: a randomized, double-blind controlled phase II/III study

Objective: The objective was to assess the safety and efficacy of a single intra-articular administration of JTA-004, a novel viscosupplement, in patients suffering from symptomatic knee osteoarthritis (OA) at 6 months. Design and methods: In this prospective, multicenter, double-blind phase II/III trial (NCT02740231), 164 patients with primary OA knee pain were randomly assigned to one of the three JTA-004 strengths or the comparator treatment (Hylan G-F 20) in a 1:1:1:1 ratio. Safety was assessed by monitoring and reporting vital signs, physical examination, adverse events and concomitant medications. The primary efficacy endpoint was the change from baseline at 6 months in WOMAC® VA3.1 pain subscale. Results: JTA-004 was shown to be well tolerated at all strengths evaluated. At 6 months, patients in the three JTA-004 groups showed a better improvement in pain compared to patients in the comparator group although statistical significance was not achieved. As the three JTA-004 strengths had a similar efficacy, a post hoc analysis was subsequently performed between the pooled JTA-004 treated patients and the comparator group. The exploratory analysis showed a 26.1±2.4 (adjusted mean±SE) mm improvement in pain in the pooled JTA-004 group vs. 15.6±4.1 mm in the comparator group at 6 months, demonstrating a statistically significant superiority of JTA-004 over the comparator (p = 0.030). Conclusions: This study provides first evidences of safety and efficacy of JTA-004 in the treatment of symptomatic knee OA. Efficacy will be further confirmed in a subsequent pivotal Phase III study

Thyroid follicle development requires Smad1/Smad5- and endothelial-dependent basement membrane assembly

Thyroid follicles, the functional units of the thyroid gland, are delineated by a monolayer of thyrocytes resting on a continuous basement membrane. Developmental mechanisms whereby follicles are formed by reorganization of a non-structured mass of non-polarized epithelial cells (folliculogenesis) largely unknown. Here we show that assembly of the epithelial basement membrane is critical for folliculogenesis and is controlled by endothelial cell invasion and by BMP-Smad signaling in thyrocytes. Thyroid-specific double Smad1 and Smad5 knockout mice (Smad1/5(dKO)) displayed growth retardation, hypothyroidism and defective follicular architecture. In Smad1/5(dKO)embryonic thyroids, epithelial cells remained associated in large clusters and formed small follicles. Although similar follicular defects are found in Vegfa(KO)thyroids, Smad1/5(dKO)thyroids had normal endothelial cell density yet impaired endothelial differentiation. Interestingly, both Vegfa(KO)and Smad1/5(dKO)thyroids displayed impaired basement membrane assembly. Furthemore, conditioned medium (CM) from embryonic endothelial progenitor cells (eEPC) rescued the folliculogenic defects of both Smad1/5(dKO)and Vegfa(KO)thyroids. Laminin α1β1γ1, abundantly released by eEPC into CM, was critically required for folliculogenesis. Thus, epithelial Smad signaling and endothelial cell invasion promote folliculogenesis via assembly of the basement membrane

Thyroid follicle development requires Smad1/Smad5- and endothelial-dependent basement membrane assembly

Thyroid follicles, the functional units of the thyroid gland, are delineated by a monolayer of thyrocytes resting on a continuous basement membrane. Developmental mechanisms whereby follicles are formed by reorganization of a non-structured mass of non-polarized epithelial cells (folliculogenesis) largely unknown. Here we show that assembly of the epithelial basement membrane is critical for folliculogenesis and is controlled by endothelial cell invasion and by BMP-Smad signaling in thyrocytes. Thyroid-specific double Smad1 and Smad5 knockout mice (Smad1/5(dKO)) displayed growth retardation, hypothyroidism and defective follicular architecture. In Smad1/5(dKO)embryonic thyroids, epithelial cells remained associated in large clusters and formed small follicles. Although similar follicular defects are found in Vegfa(KO)thyroids, Smad1/5(dKO)thyroids had normal endothelial cell density yet impaired endothelial differentiation. Interestingly, both Vegfa(KO)and Smad1/5(dKO)thyroids displayed impaired basement membrane assembly. Furthemore, conditioned medium (CM) from embryonic endothelial progenitor cells (eEPC) rescued the folliculogenic defects of both Smad1/5(dKO)and Vegfa(KO)thyroids. Laminin α1β1γ1, abundantly released by eEPC into CM, was critically required for folliculogenesis. Thus, epithelial Smad signaling and endothelial cell invasion promote folliculogenesis via assembly of the basement membrane.status: publishe