Targeting epidermal growth factor receptor to recruit newly generated neuroblasts in cortical brain injuries.

BACKGROUND: Neurogenesis is stimulated in the subventricular zone (SVZ) of mice with cortical brain injuries. In most of these injuries, newly generated neuroblasts attempt to migrate toward the injury, accumulating within the corpus callosum not reaching the perilesional area. METHODS: We use a murine model of mechanical cortical brain injury, in which we perform unilateral cortical injuries in the primary motor cortex of adult male mice. We study neurogenesis in the SVZ and perilesional area at 7 and 14 dpi as well as the expression and concentration of the signaling molecule transforming growth factor alpha (TGF-α) and its receptor the epidermal growth factor (EGFR). We use the EGFR inhibitor Afatinib to promote neurogenesis in brain injuries. RESULTS: We show that microglial cells that emerge within the injured area and the SVZ in response to the injury express high levels of TGF-α leading to elevated concentrations of TGF-α in the cerebrospinal fluid. Thus, the number of neuroblasts in the SVZ increases in response to the injury, a large number of these neuroblasts remain immature and proliferate expressing the epidermal growth factor receptor (EGFR) and the proliferation marker Ki67. Restraining TGF-α release with a classical protein kinase C inhibitor reduces the number of these proliferative EGFR+ immature neuroblasts in the SVZ. In accordance, the inhibition of the TGF-α receptor, EGFR promotes migration of neuroblasts toward the injury leading to an elevated number of neuroblasts within the perilesional area. CONCLUSIONS: Our results indicate that in response to an injury, microglial cells activated within the injury and the SVZ release TGF-α, activating the EGFR present in the neuroblasts membrane inducing their proliferation, delaying maturation and negatively regulating migration. The inactivation of this signaling pathway stimulates neuroblast migration toward the injury and enhances the quantity of neuroblasts within the injured area. These results suggest that these proteins may be used as target molecules to regenerate brain injuries.

Oxidative stress-mediated epidermal growth factor receptor activation by cigarette smoke or heated tobacco aerosol in human primary bronchial epithelial cells from multiple donors.

The epidermal growth factor receptor (EGFR) signaling pathway has essential roles in maintaining homeostasis of various tissues by regulating cell proliferation and differentiation. Deregulation of the EGFR signaling pathway is associated with various chronic diseases including chronic obstructive pulmonary disease. Cigarette smoke (CS) is known to activate EGFR, which is linked to chronic obstructive pulmonary disease. The biological sequence from CS exposure to EGFR activation is initiated by oxidative stress caused by intracellular reactive oxygen species (ROS) and the depletion of glutathione, which led to EGFR ligand secretion and EGFR activation. We hypothesized that reducing exposure to CS constituents contributes to preventing CS-inducible EGFR activation. Therefore, we examined the aerosol from heated tobacco products (HTPs) because the aerosol contains fewer chemical constituents at lower levels than CS. We exposed primary human bronchial epithelial cells from four donors to the extracts of CS from a 1R6F reference cigarette or HTP aerosol from three in-market products, including our DT3.0a. The biological sequence from ROS to EGFR activation was assessed. CS induced all the tested endpoints although inter-donor differences were observed, whereas HTPs elicited most of the biological events at higher concentrations; however, EGFR phosphorylation was not observed even at fivefold higher concentration than CS. Overall, our results indicate that HTPs are less effective than CS to elicit ROS-induced EGFR activation. The reduced-risk potential of HTPs on EGFR-related diseases should be investigated further. In addition, testing with multiple donors is warranted when considering the individual differences in responses of primary cells to stimuli.

Effects of neoadjuvant therapies on genetic regulation of targeted pathways in ER+ primary ductal breast carcinoma: A meta-analysis of microarray datasets.

Breast cancer arises as a result of multiple interactions between environmental and genetic factors. Conventionally, breast cancer is treated based on histopathological and clinical features. DNA technologies like the human genome microarray are now partially integrated into clinical practice and are used for developing new "personalized medicines" and "pharmacogenetics" for improving the efficiency and safety of cancer medications. We investigated the effects of four established therapies-for ER+ ductal breast cancer-on the differential gene expression. The therapies included single agent tamoxifen, two-agent docetaxel and capecitabine, or combined three-agents CAF (cyclophosphamide, doxorubicin, and fluorouracil) and CMF (cyclophosphamide, methotrexate, and fluorouracil). Genevestigator 8.1.0 was used to compare five datasets from patients with infiltrating ductal carcinoma, untreated or treated with selected drugs, to those from the healthy control. We identified 74 differentially expressed genes involved in three pathways, i.e., apoptosis (extrinsic and intrinsic), oxidative signaling, and PI3K/Akt signaling. The treatments affected the expression of apoptotic genes (TNFRSF10B [TRAIL], FAS, CASP3/6/7/8, PMAIP1 [NOXA], BNIP3L, BNIP3, BCL2A1, and BCL2), the oxidative stress-related genes (NOX4, XDH, MAOA, GSR, GPX3, and SOD3), and the PI3K/Akt pathway gene (ERBB2 [HER2]). Breast cancer treatments are complex with varying drug responses and efficacy among patients. This necessitates identifying novel biomarkers for predicting the drug response, using available data and new technologies. GSR, NOX4, CASP3, and ERBB2 are potential biomarkers for predicting the treatment response in primary ER+ ductal breast carcinoma.

iRhoms 1 and 2 are essential upstream regulators of ADAM17-dependent EGFR signaling.

The metalloproteinase ADAM17 (a disintegrin and metalloprotease 17) controls EGF receptor (EGFR) signaling by liberating EGFR ligands from their membrane anchor. Consequently, a patient lacking ADAM17 has skin and intestinal barrier defects that are likely caused by lack of EGFR signaling, and Adam17(-/-) mice die perinatally with open eyes, like Egfr(-/-) mice. A hallmark feature of ADAM17-dependent EGFR ligand shedding is that it can be rapidly and posttranslationally activated in a manner that requires its transmembrane domain but not its cytoplasmic domain. This suggests that ADAM17 is regulated by other integral membrane proteins, although much remains to be learned about the underlying mechanism. Recently, inactive Rhomboid 2 (iRhom2), which has seven transmembrane domains, emerged as a molecule that controls the maturation and function of ADAM17 in myeloid cells. However, iRhom2(-/-) mice appear normal, raising questions about how ADAM17 is regulated in other tissues. Here we report that iRhom1/2(-/-) double knockout mice resemble Adam17(-/-) and Egfr(-/-) mice in that they die perinatally with open eyes, misshapen heart valves, and growth plate defects. Mechanistically, we show lack of mature ADAM17 and strongly reduced EGFR phosphorylation in iRhom1/2(-/-) tissues. Finally, we demonstrate that iRhom1 is not essential for mouse development but regulates ADAM17 maturation in the brain, except in microglia, where ADAM17 is controlled by iRhom2. These results provide genetic, cell biological, and biochemical evidence that a principal function of iRhoms1/2 during mouse development is to regulate ADAM17-dependent EGFR signaling, suggesting that iRhoms1/2 could emerge as novel targets for treatment of ADAM17/EGFR-dependent pathologies.

Transforming Growth Factor Alpha Taq I Polymorphisms and Nonsyndromic Cleft Lip and/or Palate Risk: A Meta-Analysis.

BACKGROUND: A series of epidemiological studies were conducted to investigate the association between transforming growth factor alpha ( TGFA) polymorphism and nonsyndromic cleft lip and/or palate (CL/P) risk, but the findings remain conflicting. The present meta-analysis summarizes the association between the TGFA Taq I polymorphisms and nonsyndromic CL/P risk. METHODS: We searched PubMed, EMBASE, Web of Science, and Chinese Biomedical Literature databases from their inception to May 1, 2015. Fixed-effects or random-effects models were used to calculate the pooled odds ratio for two genetic comparisons (heterozygous mutation versus wild type, homozygous mutation versus wild type). All of the statistical tests were conducted by STATA 10.0 (StataCorp, College Station, TX). RESULTS: A total of 26 case-control studies were identified for this meta-analysis. There was evidence of a significant association between the TGFA Taq I polymorphism and nonsyndromic CL/P risk in the overall population. The TGFA polymorphism was associated with nonsyndromic CL/P susceptibility in Asian populations under any of genetic models. However, in subgroup analysis, we did not find a significant association of TGFA gene polymorphisms with a reduced cancer risk in White and other populations and (recessive model, odds ratio = 2.37, 95% confidence intervals = 0.92-6.07; odds ratio = 3.45, 95% confidence intervals = 1.07-11.09, respectively). CONCLUSION: Our study indicates that the TGFA gene polymorphism might be associated with nonsyndromic CL/P susceptibility. However, these findings still need to be confirmed by single, large, well-designed prospective studies.

From wavy hair to naked proteins: the role of transforming growth factor alpha in health and disease.

Since its discovery in 1978 and cloning in 1984, transforming growth factor-alpha (TGF-α, TGFA) has been one of the most extensively studied EGF receptor (EGFR) ligands. In this review, we provide a historical perspective on TGFA-related studies, highlighting what we consider important advances related to its function in normal and disease states.

Effects of calcium and vitamin D3 on transforming growth factors in rectal mucosa of sporadic colorectal adenoma patients: a randomized controlled trial.

Transforming growth factor alpha (TGFα) and TGFß1 are growth-promoting and -inhibiting autocrine/paracrine growth factors, respectively, that may (1) affect risk for colorectal cancer and (2) be modifiable by anti-proliferative exposures. The effects of supplemental calcium and vitamin D3 on these two markers in the normal-appearing colorectal mucosa in humans are unknown. We conducted a pilot, randomized, double-blind, placebo-controlled, 2 × 2 factorial clinical trial (n = 92; 23/treatment group) of calcium 2 g and/or vitamin D3 800 IU/d versus placebo over 6 mo. TGFα and TGFß1 expression was measured in biopsies of normal-appearing rectal mucosa using automated immunohistochemistry and quantitative image analysis at baseline and 6-mo follow-up. In the calcium, vitamin D3 , and calcium plus vitamin D3 groups relative to the placebo group (1) the mean overall expression of TGFß1 increased by 14% (P= 0.25), 19% (P = 0.17), and 22% (P = 0.09); (2) the ratio of TGFα expression in the upper 40% (differentiation zone) to that in the lower 60 (proliferation zone) of the crypts decreased by 34% (P = 0.11), 31% (P = 0.22), and 26% (P = 0.33); and (3) the TGFα/TGFß1 ratio in the upper 40% of the crypts decreased by 28% (P = 0.09), 14% (P = 0.41), and 22% (P = 0.24), respectively. These preliminary results, although not statistically significant, suggest that supplemental calcium and vitamin D3 may increase TGFß1 expression and shift TGFα expression downward from the differentiation to the proliferation zone in the crypts in the normal-appearing colorectal mucosa of sporadic colorectal adenoma patients, and support further investigation in a larger clinical trial.

Parathyroid-specific epidermal growth factor-receptor inactivation prevents uremia-induced parathyroid hyperplasia in mice.

BACKGROUND: In chronic kidney disease (CKD), parathyroid hyperplasia contributes to high serum parathyroid hormone (PTH) and also to an impaired suppression of secondary hyperparathyroidism by calcium, vitamin D and fibroblast growth factor 23 (FGF23). In rats, systemic inhibition of epidermal growth factor receptor (EGFR) activation markedly attenuated uremia-induced parathyroid hyperplasia and vitamin D receptor (VDR) loss, hence restoring the response to vitamin D. Therefore, we propose that parathyroid-specific EGFR inactivation should prevent CKD-induced parathyroid hyperplasia. METHODS: A dominant-negative human EGFR mutant, which forms non-functional heterodimers with full-length endogenous EGFR, was successfully targeted to the parathyroid glands (PTGs) of FVB/N mice, using the 5' regulatory sequence of the PTH promoter. The parathyroid phenotype and serum chemistries of wild-type (WT) and transgenic mice were examined after 14 weeks of either sham operation or 75% renal mass reduction (NX). RESULTS: Both genotypes had similar morphology and body weight, and NX-induction enhanced similarly serum blood urea nitrogen compared with sham-operated controls. However, despite similar serum calcium, phosphate and FGF23 levels in NX mice of both genotypes, parathyroid EGFR inactivation sufficed to completely prevent the marked increases in PTG enlargement, serum PTH and in parathyroid levels of transforming growth factor-α, a powerful EGFR-activator, and the VDR reductions observed in WT mice. CONCLUSION: In CKD, parathyroid EGFR activation is essential for parathyroid hyperplasia and VDR loss, rendering this transgenic mouse a unique tool to scrutinize the pathogenesis of parathyroid and multiple organ dysfunction of CKD progression unrelated to parathyroid hyperplasia.

Qualitative changes in the proteome of extracellular vesicles accompanying cancer cell transition to mesenchymal state.

Transitions of the cancer cell phenotype between epithelial and mesenchymal states (EMT) are likely to alter the patterns of intercellular communication. In this regard we have previously documented that EMT-like changes trigger quantitative rearrangements in exosomal vesicle emission in A431 cancer cells driven by oncogenic epidermal growth factor receptor (EGFR). Here we report that extracellular vesicles (EVs) produced by these cancer cells in their epithelial and mesenchymal states exhibit profound qualitative differences in their proteome. Thus, induction of the EMT-like state through blockade of E-cadherin and EGFR stimulation provoked a mesenchymal shift in cellular morphology and enrichment in the CD44-high/CD24-low immunophenotype, often linked to cellular stemness. This change also resulted in reprogramming of the EV-related proteome (distinct from that of corresponding cells), which contained 30 unique protein signals, and revealed enrichment in pathways related to cellular growth, cell-to-cell signaling, and cell movement. Some of the most prominent EV-related proteins were validated, including integrin α2 and tetraspanin CD9. We propose that changes in cellular differentiation status translate into unique qualitative rearrangements in the cargo of EVs, a process that may have implications for intercellular communication and could serve as source of new biomarkers to detect EMT-like processes in cancer.

Advanced biosensors for nanomaterial-based detection of transforming growth factor alpha and beta, a class of major polypeptide regulators.

Transforming growth factors (TGFs) regulate several cellular processes including, differentiation, growth, migration, extracellular matrix production, and apoptosis. TGF alpha (TGF-α) is a heterogeneous molecule containing 160 amino acid residues. It is a potent angiogenesis promoter that is activated by JAK-STAT signaling. Whereas TGF beta (TGF-ß) consists of 390-412 amino acids. Smad and non-Smad signaling both occur in TGF beta. It is linked to immune cell activation, differentiation, and proliferation. It also triggers pre-apoptotic responses and inhibits cell proliferation. Both growth factors have a promising role in the development and homeostasis of tissues. Defects such as autoimmune diseases and cancer develop mechanisms to modulate checkpoints of the immune system resulting in altered growth factors profile. An accurate amount of these growth factors is essential for normal functioning, but an exceed or fall behind the normal level is alarming as it is linked to several disorders. This demands techniques for TGF-α and TGF-ß profiling to effectively diagnose diseases, monitor their progression, and assess the efficacy of immunotherapeutic drugs. Quantitative detection techniques including the emergence of biosensing technology seem to accomplish the purpose. Until the present time, few biosensors have been designed in the context of TGF-α and TGF-ß for disease detection, analyzing receptor binding, and interaction with carriers. In this paper, we have reviewed the physiology of transforming growth factor alpha and beta, including the types, structure, function, latent/active forms, signaling, and defects caused. It involves the description of biosensors on TGF-α and TGF-ß, advances in technology, and future perspectives.

TACE-dependent TGFα shedding drives triple-negative breast cancer cell invasion.

The epidermal growth factor receptor (EGFR) is frequently expressed in triple-negative breast cancer (TNBC) and is a marker of poor prognosis in this patient population. Because activating mutations in this kinase are very rare events in breast cancer, we screened breast tumor gene expression profiles to examine the distribution of EGFR ligand expression. Of the six known EGFR ligands, transforming growth factor alpha (TGFα) was expressed more highly in triple-negative breast tumors than in tumors of other subtypes. TGFα is synthesized as a transmembrane precursor requiring tumor necrosis factor alpha converting enzyme (TACE)/ADAM17-dependent proteolytic release to activate its receptor. In our study, we show that an inhibitor of this proteolytic release blocks invasion, migration and colony formation by several TNBC cell lines. Each of the effects of the drug was reversed upon expression of a soluble TGFα mutant that does not require TACE activity, implicating this growth factor as a key metalloproteinase substrate for these phenotypes. Together, these data demonstrate that TACE-dependent TGFα shedding is a key process driving EGFR activation and subsequent proliferation and invasion in TNBC cell lines.

Intermittent versus continuous erlotinib with concomitant modified "XELOX" (q3W) in first-line treatment of metastatic colorectal cancer: correlation with serum amphiregulin and transforming growth factor alpha.

BACKGROUND: This study evaluated the activity of 2 schedules of erlotinib in combination with chemotherapy, and the prognostic significance of serum amphiregulin (AREG) and transforming growth factor alpha (TGFa) in metastatic colorectal cancer. METHODS: A total of 60 untreated patients were randomized to a "continuous" (CON; erlotinib 100 mg daily) or an "intermittent" (INT; erlotinib 150 mg on alternate day on day 2 to 14, then 150 mg daily on days 15 to 21) schedule of erlotinib with a modified XELOX (capecitabine plus oxaliplatin) regimen. Serum levels of AREG and TGFa were determined serially. RESULTS: Baseline characteristics were similar between the 2 arms. Of the 58 patients evaluated for response, there was a nonsignificant trend toward a slightly higher overall response rate in the INT arm (66.7%) versus the CON arm (56.7%). At a median follow-up of 2.8 years, the median overall survival was 18.8 months (95% confidence interval = 11.3-22.9 months) and 20.7 months (95% confidence interval = 12.5-31 months, P = .19) for the CON and INT arm, respectively. KRAS mutation did not predict drug response. The 2 arms did not differ significantly in toxicity. Baseline serum TGFa was an independent predictor of progression-free survival, whereas a drop in serum TGFa and AREG levels following 3 to 4 cycles of treatment were associated with shorter progression-free survival and overall survival, respectively. CONCLUSIONS: The intermittent erlotinib schedule was associated with a higher response rate, although this is not statistically significant. Serum TGFa and AREG levels have prognostic significance in erlotinib-treated patients with colorectal cancer, and further studies are warranted.

Bone morphogenetic protein 4 supports the initial differentiation of hen (Gallus gallus) granulosa cells.

In the hen ovary, selection of a follicle into the preovulatory hierarchy occurs from a small cohort of prehierarchal (6-8 mm) follicles. Prior to follicle selection the granulosa layer remains in an undifferentiated state despite elevated follicle-stimulating hormone receptor (FSHR) expression. The present studies describe a role for bone morphogenetic protein 4 (BMP4) in supporting FSHR mRNA expression in granulosa cells from prehierarchal follicles and promoting differentiation at follicle selection. Culture of undifferentiated granulosa cells in culture medium alone resulted in a significant decline in levels of FSHR mRNA (by ~80% compared to freshly collected cells). By comparison, granulosa cultured with BMP4 (10-100 ng/ml) maintained FSHR and expression at approximately in vivo levels. Because both granulosa and theca tissues from prehierarchal follicles express BMP4, it is suggested that BMP4 acts in a paracrine and/or autocrine fashion to support elevated FSHR expression prior to follicle selection. Granulosa cells cultured with BMP4 for 24 h also initiated FSH-induced cAMP production and indirectly initiated anti-Mullerian hormone (AMH), CYP11A, and STAR expression plus progesterone production. However, pretreatment with the BMP antagonist NOGGIN or the mitogen-activated protein kinase (MAPK) agonist transforming growth factor alpha attenuated or blocked each action promoted by BMP4. We conclude that prior to and immediately after selection, BMP4 serves to support FSHR expression within the granulosa layer, yet prior to selection, multiple factors (including inhibitory MAPK signaling, AMH, and BMP antagonists) can modulate FSHR expression and suppress FSH-mediated cell signaling to prevent granulosa cell differentiation prior to follicle selection.

Determination of mTOR signal pathway in MMTV-TGFα mice ovary at different ages.

Transforming growth factor alpha (TGFα), a member of the epidermal growth factor (EGF) family, regulates cell proliferation, differentiation, and development, and involves follicular development and viability. In ovaries, TGFα is shown localized in granulosa cells (GCs) of primary follicles, theca cells (TCs) of pre-antral, antral and pre-ovulatory follicles. TGFα overexpression in mouse mammary tumor virus (MMTV-TGFα) transgenic mice causes mammary tumor after 50 weeks. However, follicular development and preservation of the ovarian follicle reserve-mediating follicle stimulating hormone (FSH) response are unknown. Mammalian target of rapamycin (mTOR) is a key regulator for cell proliferation, growth, differentiation, and apoptosis, and important for ovarian folliculogenesis and oocyte maturation. The study aim determines TGFα overexpression during folliculogenesis via mTOR signaling pathway in ovaries from 10-, 18-, 50-, and 82-week-old MMTV-TGFα mice. Histological analysis was performed, along with western blot for mTOR, p-mTOR, P70S6K, PCNA, and Caspase-3, and quantitative RNA (qRT-PCR) for mTOR and P70S6K. Developing follicles number decreased and atretic follicles number increased with aging in MMTV-TGFα mice ovary. Ovaries at 18 and 82 weeks had decreased PCNA and increased Caspase-3 protein expression levels as compared to 10-week ovaries. Protein expression levels of mTOR and p-mTOR decreased gradually from ovaries at 10-18 weeks, increased at 50 weeks and decreased again at 82 weeks. These results indicate that TGFα may be one regulator of healthy follicular development and affect mTOR signaling pathway during ovarian aging. Thus, over-expression of TGFα might lead to reduced ovarian reserve and premature ovarian insufficiency.

Rescue of neurogenesis and age-associated cognitive decline in SAMP8 mouse: Role of transforming growth factor-alpha.

Neuropathological aging is associated with memory impairment and cognitive decline, affecting several brain areas including the neurogenic niche of the dentate gyrus of the hippocampus (DG). In the healthy brain, homeostatic mechanisms regulate neurogenesis within the DG to facilitate the continuous generation of neurons from neural stem cells (NSC). Nevertheless, aging reduces the number of activated neural stem cells and diminishes the number of newly generated neurons. Strategies that promote neurogenesis in the DG may improve cognitive performance in the elderly resulting in the development of treatments to prevent the progression of neurological disorders in the aged population. Our work is aimed at discovering targeting molecules to be used in the design of pharmacological agents that prevent the neurological effects of brain aging. We study the effect of age on hippocampal neurogenesis using the SAMP8 mouse as a model of neuropathological aging. We show that in 6-month-old SAMP8 mice, episodic and spatial memory are impaired; concomitantly, the generation of neuroblasts and neurons is reduced and the generation of astrocytes is increased in this model. The novelty of our work resides in the fact that treatment of SAMP8 mice with a transforming growth factor-alpha (TGFα) targeting molecule prevents the observed defects, positively regulating neurogenesis and improving cognitive performance. This compound facilitates the release of TGFα in vitro and in vivo and activates signaling pathways initiated by this growth factor. We conclude that compounds of this kind that stimulate neurogenesis may be useful to counteract the neurological effects of pathological aging.

Anabolic phenotype in cartilage-specific mitogen-inducible gene-6 knockout mice is independent of transforming growth factor-α.

Background/objective: Osteoarthritis (OA) is a whole joint disorder with no disease modifying treatment currently available. The Epidermal Growth Factor Receptor (EGFR) signaling pathway plays an important role in cartilage/bone development and its ligand transforming growth factor-α (TGFα) is upregulated in OA. In contrast, Mitogen-inducible gene 6 (Mig6) is a negative regulator of EGFR, and cartilage-specific Mig-6 deletion results in anabolic effects on cartilage and formation of chondro-osseus nodules (CON). We aimed to attenuate EGFR signaling by inhibiting TGFα production in cartilage-specific Mig6 deficient mice, to test whether this would prevent the formation of CONs. Methods: We generated double knockout mice by crossing cartilage-specific Mig-6fl/flCol2a1-Cre+/- and whole-body Tgfa± mice to generate experimental and control wild-type mice. Knee and elbow sections were used to examine articular cartilage thickness, cell density, and osteoclast presence. Additionally, immunohistochemistry was completed to analyze phospho-EGFR and SOX9. Results: Mig-6 deficient mice display cartilage thickening and CONs at 12 weeks in both the elbow and knee joints, which is independent of TGFα ligand presence. Similarly, articular cartilage cell density is increased in Mig6-cKO/Tgfa-KO and Mig6-cKOmice, but not Tgfa-KO mice, and displays increased SOX9 and phospho-EGFR staining. Conclusion: The articular cartilage displays increased thickness/cell density and CON formation independent of the presence of TGFα, suggesting the anabolic phenotype in the Mig6-deficient mice is independent of TGFα/EGFR binding. The anabolic phenotype may be due to an alternative EGFR ligand activation, or other non-EGFR specific mechanism. More research is required to elucidate the exact pathway responsible for the anabolic effects.

Stimulatory effects of TGFα in granulosa cells of bovine small antral follicles.

Intraovarian growth factors play a vital role in influencing the fate of ovarian follicles. They affect proliferation and apoptosis of granulosa cells (GC) and can influence whether small antral follicles continue their growth or undergo atresia. Transforming growth factor-alpha (TGFα), an oocyte-derived growth factor, is thought to regulate granulosa cell function; yet its investigation has been largely overshadowed by emerging interest in TGF-beta superfamily members, such as bone morphogenetic proteins (BMP) and anti-Mullerian hormone (AMH). Here, effects of TGFα on bovine GC proliferation, intracellular signaling, and cytokine-induced apoptosis were evaluated. Briefly, all small antral follicles (3-5 mm) from slaughterhouse specimens of bovine ovary pairs were aspirated and the cells were plated in T25 flasks containing DMEM/F12 medium, 10% FBS, and antibiotic-antimycotic, and incubated at 37 °C in 5% CO2 for 3 to 4 d. Once confluent, the cells were sub-cultured for experiments (in 96-, 12-, or 6-well plates) in serum-free conditions (DMEM/F12 medium with ITS). Exposure of the bGC to TGFα (10 or 100 ng/mL) for 24 h stimulated cell proliferation compared to control (P < 0.05; n = 7 ovary pairs). Proliferation was accompanied by a concomitant increase in mitogen-activated protein kinase (MAPK) signaling within 2 h of treatment, as evidenced by phosphorylated ERK1/2 expression (P < 0.05, n = 3 ovary pairs). These effects were entirely negated, however, by the MAPK inhibitor, U0126 (10uM, P < 0.05). Additionally, prior exposure of the bGC to TGFα (100 ng/mL) failed to prevent Fas Ligand (100 ng/mL)-induced apoptosis, as measured by caspase 3/7 activity (P < 0.05, n = 7 ovary pairs). Collectively, the results indicate TGFα stimulates proliferation of bGC from small antral follicles via a MAPK/ERK-mediated mechanism, but this action alone fails to prevent apoptosis, suggesting that TGFα may be incapable of promoting their persistence in follicles during the process of follicular selection/dominance.

A variety of hormones regulate ovarian function in the cow, thus influencing fertility. One such hormone, transforming growth factor-alpha, TGFα, is expressed by the oocyte (egg) of the bovine ovary; yet little other information about the actions of this molecule on ovarian cells is available. In this study, we determined that although TGFα directly stimulates growth and proliferation of cells of the bovine ovary, and does so via specific signaling mechanisms, it fails to prevent immune-mediated programmed cell death. The latter observation diminishes the importance of TGFα relative to other oocyte-derived hormones in terms of ovarian function and overall animal fertility.

A TGF-α and TGF-ß1 Poloxamer-based micelle/hydrogel composite: A promising novel candidate for the treatment of anosmia.

Anosmia is the inability to smell or loss of the sense of smell. It can reduce your ability to detect the smell of smoke, gas leaks, or spoiled food, as well as hinder the quality of life related to social interactions and feelings of well-being. In the current study, a drug delivery composite was designed to cure anosmia and its efficiency in delivering transforming growth factor alpha (TGF-α) and transforming growth factor beta 1 (TGF-ß1) to the nasal cavity was evaluated. Bovine serum albumin (BSA) was used as a model protein for encapsulation into Poloxamers 407 micelles. For the optimization of the BSA-micelle formulation, a two-parameter five-level central composite design (CCD) was applied. The BSA-micelle was optimized with a particle size of 41 nm, drug loading of 8%, and encapsulation efficiency of 74%. Further, the BSA-micelle was characterized by FESEM, TEM, and FTIR. The analysis of release profile suggested high-paced free BSA release compared to the gradual and prolonged release of BSA-micelle/hydrogel and BSA-micelles. The cytotoxicity assay demonstrated the safety of TGF-α and TGF-ß1-micelles/hydrogel. Moreover, it was observed that TGF-α and TGF-ß1 within the hydrogels promote cellular viability and human olfactory ectomesenchymal stem cell OE-MSCs proliferation. In conclusion, According to the results of our study, the TGF-α and TGF-ß1-micelle/hydrogel-based delivery system provides a suitable alternative for anosmia treatment.

Diagnosis and Management of Ménétrier Disease in Children: A Case Series Review.

PURPOSE: Ménétrier disease (MD) was first described in 1888, and 50 cases have been reported until now. We aimed to discuss the etiology, diagnostics, and management of MD in children. METHODS: We searched for case reports published from 2014 till 2019 in English using PubMed. Articles were selected using subject headings and key words of interest to the topic. Interesting references of the included articles were also included. RESULTS: The pathophysiology of MD is still uncertain. However, overexpression of transforming growth factor alpha with transformation of the gastric mucosa has been observed, which may be mediated by genetics and provoked by an infectious trigger. Clinically, MD is diagnosed by abdominal pain, vomiting, anorexia, and edema secondary to hypoalbuminemia. A gastroscopy with biopsy is the gold standard for the diagnosis of MD. In children, the disease is self-limiting and only requires supportive treatment. In general, children have a good prognosis and recover spontaneously within a few weeks. CONCLUSION: Few pediatric cases of MD have been described in recent years, and with all different etiology. Endoscopy with biopsy remains the golden standard for the diagnosis of MD, and in children, the disease is self-limiting.

ARA-linker-TGFαL3: a novel chimera protein to target breast cancer cells.

Targeted cancer therapies based on overexpressed receptors and the fractions containing immunotoxins and bacterial metabolites are one of the well-known methods to overcome the chemotherapy resistance of cancer cells. In this paper, we designed ARA-linker-TGFαL3, using Arazyme, a Serratia proteamaculans metabolite, and a third loop segment of TGFα to target EGFR-expressing breast cancer cells. After cloning in pET28a (+), the expression of recombinant protein was optimized in Escherichia coli strain BL21 (DE3). MDA-MB-468 (EGFR positive) and MDA-MB-453 (EGFR negative) breast cancer cell lines were employed. Also, the chemotherapeutic drug, Taxotere (Docetaxel), was employed to compare cytotoxicity effects. Cell ELISA assessed the binding affinity of recombinant proteins to the receptor, and the cytotoxicity was detected by MTT and lactate dehydrogenase release assays. The interfacing with cancer cell adhesion was evaluated. Furthermore, the induction of apoptosis was examined utilizing flow cytometric analysis, and caspase-3 activity assay. Moreover, RT-PCR was conducted to study the expression of apoptosis (bax, bcl2, and casp3), angiogenesis (vegfr2), and metastasis (mmp2 and mmp9) genes. ARA-linker-TGFαL3 revealed a higher binding affinity, cytotoxicity, and early apoptosis induction in MDA-MB-468 cells compared to the effects of Arazyme while both recombinant proteins showed similar effects on MDA-MB-453. In addition, the Taxotere caused the highest cytotoxicity on cancer cells through induction of late apoptosis. Meanwhile, the expression of angiogenesis and metastasis genes was decreased in both cell lines after treatment with either ARA-linker-TGFαL3 or Arazyme. Our in vitro results indicated the therapeutic effect of ARA-linker-TGFαL3 on breast cancer cells.