Concentrations Of TGF-alpha Research Articles

Tear biomarkers and corneal sensitivity as an indicator of neuropathy in type 2 diabetes

AimsExplore potential of 31 tear biomarkers involved in screening for diabetic peripheral neuropathy (DPN). Assess the utility of aesthesiometry for measuring corneal damage in DPN and determine optimal cutoff point for detecting DPN. MethodsScreening test pilot study recruited 90 participants from a tertiary hospital in Lima, Peru. Participants were grouped by diabetes and neuropathy status. Tears collected on Schirmer strips, and proteins measured by both ELISA and multiplex-bead assay. Corneal sensitivity was measured by aesthesiometry, and DPN by vibration perception threshold testing. ResultsThere were 89 participants included in the analysis. The mean age was 55.7 ± 1.46, and 58.4% were female. MMP-9 and TGF-alpha concentrations were higher in participants with DPN versus diabetes alone, though not significant. Aesthesiometry was decreased in individuals with DPN when compared to participants with diabetes alone (p < 0.01) and normal controls (p < 0.01). Optimal cutoff point for aesthesiometry was found to be 5.8 cm, with 79% sensitivity and 75% specificity. ConclusionsTears are an insufficient standalone tool for detecting DPN based on the biomarkers analyzed. Aesthesiometry is a simple, inexpensive, and accurate method to assess corneal damage associated with moderate-severe DPN, and its integration into screening practices has potential to improve detection of DPN in poor-resource settings.

Predictive value of serum HGF for treatment response to EGFR tyrosine kinase inhibitor in patients with lung adenocarcinoma.

7563 Background: EGFR mutation status has emerged to be a validated predictive biomarker for the response to EGFR-tyrosine kinase inhibitors (EGFR-TKI) treatment in non-small cell lung cancer. However, other predictive biomarkers for EGFR-TKI have not been identified. Methods: We retrospectively analyzed the serum concentration of 13 molecules in a cohort of 95 patients (pts) with lung adenocarcinoma who received EGFR-TKI treatment from 3 centers. Pretreatment serum concentrations of HGF, amphiregulin, Beta-cellulin, EGF, sEGFR, Epiregulin, FGF-basic, HB-EGF, PDGF-BB, PIGF, tenascin C, TGF-alpha and VEGF were measured using ELISA and multiplex immunoassay system. Results: Serum concentrations of HGF and VEGF differ significantly between pts with progressive-disease (PD) and those without PD (HGF, p<0.0001, VEGF, p<0.0001). HGF and VEGF were strongly associated with progression free survival (PFS) and overall survival (OS) in univariate Cox analysis (all tests for hazard ratio [HR] showed p<0.0001). In multivariate Cox analysis stratified by EGFR mutation status (mutant, n=20 /wild-type, n=23 /unknown, n=52), high concentration of HGF showed a shorter PFS and OS independently of significant clinical variables including gender and PS (Table). Conclusions: Serum HGF is closely related with clinical outcomes of EGFR-TKI treatment and it raise the possibility of further refinement for the selection of patients in combination with EGFR mutation status. Our findings warrant further investigations in a prospective study to evaluate whether HGF is a predictive/prognostic biomarker for EGFR-TKI. Multivariate analysis stratified by EGFR mutation status (n = 95); HGF and VEGF were logtransformed Progression-free survival HR 95% CI P HR 95% CI P Gender M vs. F 1.28 (0.77-2.15) 0.34 1.72 (0.96-3.10) 0.07 PS 2-4 vs. 0-1 0.64 (0.36-1.12) 0.11 1.52 (0.86-2.66) 0.15 HGF 6.28 (2.65-14.9) <0.0001 2.78 (1.28-6.01) <0.0001 VEGF 1.94 (1.11-3.39) 0.0204 1.60 (0.85-3.02) 0.15 No significant financial relationships to disclose.

Inflammatory changes of the gastric mucosa and serum concentration of chosen growth factors in children

To assess whether there is a correlation between the severity of gastritis and concentration of chosen growth factors in the serum of children infected with H. pylori. The study included 64 children of whom 50% (Group I) were infected with H. pylori and had gastritis; 18.7% (Group II) of the examined children had a positive titre of IgG against H. pylori and normal gastric mucosa. Controls (Group III) comprised 31.3%. The gastric mucosa was evaluated histopathologically according to the Sydney System. The serum concentrations of growth factors: EGF, TGF-alpha, VEGF, were determined using ELISA. Mean concentrations of the growth factors were also the highest in Group I compared to Group II and Group III (EGF - 137.3+/-10.4 pg/mL, TGF-alpha - 0.4+/-1.2 pg/mL, VEGF - 146.8 pg/mL). Analysis of correlations between growth factors and the severity of gastritis as well as the activity of antral gastric mucosa inflammation proved that mean EGF concentration in H. pylori infected children was the highest (149.5+/-84.8 pg/mL) in severe gastritis, whereas mean concentrations of TGF-alpha (2.0+/-4.3 pg/mL) and of VEGF (148.1+/-92.6 pg/mL) were the highest in moderate gastritis. Mean concentrations of EGF (155.1+/-116.4 pg/mL) and of VEGF (156.0+/-118.9 pg/mL) were the highest in high activity antral gastritis, whereas the mean concentration of TGF-alpha was the highest (2.0+/-4.2 pg/ml) in moderate activity gastritis. In the children with H. pylori infection, serum concentrations of EGF, TGF-alpha, VEGF were the highest in moderate and severe antral gastritis.

Postnatal Changes in Testicular Concentrations of Transforming Growth Factors-Alpha and-Beta 1, 2 and 3 and Serum Concentrations of Insulin Like Growth Factor I in Bulls

Based on work largely in laboratory animals, transforming growth factors (TGF) and insulin like growth factors (IGF) could be regulators of testicular development. The aim of this study was to see if TGF-alpha and -beta 1, 2 and 3 are present in the bovine testis and to monitor concentrations of these factors in the testis and IGF-I in serum during reproductive development. Separate groups of Hereford x Charolais calves (n = 6) were castrated every 4 weeks from 5 to 33 weeks of age and at 56 weeks of age. A week prior to castration, from 5 to 33 weeks of age, blood was collected every 15 min for 10 h. Serum IGF-I concentrations increased from 8 to 12 weeks of age, decreased from 24 to 28 weeks and increased to 32 weeks of age (p < 0.05). Testicular TGF-alpha concentrations increased from 13 to 17 weeks of age, decreased to 21 weeks and from 33 to 56 weeks of age (p < 0.05). Testicular TGF-beta 1 concentrations decreased from 17 to 21 weeks of age, increased to 25 weeks and decreased from 25 to 33 weeks of age (p < 0.05). Testicular TGF-beta 2 concentrations increased from 5 to 17 weeks of age, decreased to 21 weeks, increased to 25 weeks and decreased at 29 weeks of age (p < 0.05). Testicular TGF-beta 3 concentrations increased from 13 to 17 weeks of age, decreased to 21 weeks and from 25 to 29 weeks of age (p < 0.05). We concluded that TGF-alpha and TGF-beta 1, 2 and 3 are present in the testis of the bull calf, and changes in concentrations with age suggest a functional role in the development of the testis.

Transforming growth factor-alpha stimulates enterocyte proliferation and accelerates intestinal recovery following methotrexate-induced intestinal mucositis in a rat and a cell culture model

Recent evidence suggests that transforming growth factor-alpha (TGF-alpha) enhances enterocyte proliferation and exerts a gut trophic effect. The purpose of the present study was to evaluate the effect of TGF-alpha on enterocyte proliferation and intestinal recovery following methotrexate (MTX)-induced intestinal mucositis in rats and in Caco-2 cells. Nonpretreated Caco-2 cells and those pretreated with MTX were incubated with increasing concentrations of TGF-alpha. Cell proliferation was determined by FACS cytometry. Adult rats were divided into three groups: control rats treated with vehicle, MTX rats treated with one dose (20 microg/kg) of MTX given intraperitoneally, and MTX-TGF-alpha rats treated with one dose of MTX followed by two doses of TGF-alpha (75 microg/kg a day). Three days after MTX injection, rats were sacrificed. Intestinal mucosal damage (Park's score), mucosal structural changes, and enterocyte proliferation were measured at sacrifice. Western blotting was used to determine the level of extracellular signal-related kinase (ERK) protein, a marker of cell proliferation. A nonparametric Kruskal-Wallis ANOVA test was used for statistical analysis with P value less than 0.05 considered statistically significant. The in vitro experiment demonstrated that treatment with TGF-alpha of Caco-2 cells resulted in a significant stimulation of cell proliferation in a dose-dependent manner. The in vivo experiment showed that treatment with TGF-alpha resulted in a significant increase in bowel and mucosal weight, DNA and protein content in jejunum and ileum, villus height in jejunum and ileum, crypt depth in ileum, and increased cell proliferation in jejunum and ileum compared to the MTX group. MTX-TGF-alpha rats also had a significantly lower intestinal injury score in ileum when compared to MTX animals. The increase in levels of cell proliferation in MTX-TGF-alpha rats corresponded with the increase in ERK protein levels in intestinal mucosa. Treatment with TGF-alpha prevents mucosal injury, enhances ERK-induced enterocyte proliferation, and improves intestinal recovery following MTX-induced intestinal mucositis in rats. These findings correlated with the observation that TGF-alpha also caused a significant stimulation of cell proliferation in a Caco-2 cell culture model treated with MTX. These observations may have significant implications for the treatment of patients on chemotherapy who develop severe mucositis.

Effect of transforming growth factor-alpha on enterocyte apoptosis is correlated with EGF receptor expression along the villus-crypt axis during methotrexate-induced intestinal mucositis in a rat

The purpose of the present study was to evaluate the effect of transforming-growth factor-alpha (TGF-alpha) on enterocyte apoptosis following methotrexate (MTX) induced intestinal mucositis in a rat and in Caco-2 cells. Non-pretreated and pretreated with MTX Caco-2 cells were incubated with increasing concentrations of TGF-alpha. Cell apoptosis was determined by FACS cytometry. Adult rats were divided into four groups: Control, Control-TGF-alpha, MTX, and MTX- TGF-alpha rats. Three days later rats were sacrificed. Enterocyte apoptosis were measured at sacrifice. RT-PCR and Western Blotting was used to determine the level of Bax and Bcl-2 mRNA and protein. Real time PCR was used to measure epidermal growth factor receptor (EGFr) expression along the villus-crypt axis. The in vitro experiment has shown that treatment with TGF-alpha of Caco-2 cells results in a significant inhibition of cell apoptosis in a dose-dependent manner. In vivo experiment, a decreased levels of apoptosis in MTX- TGF-alpha rats corresponded with the decrease in Bax and with the increase in Bcl-2 at both mRNA and protein levels. The inhibiting effect of TGF-alpha on enterocyte apoptosis was strongly correlated with EGFr expression along the villus-crypt axis. In conclusion, treatment with TGF-alpha inhibits enterocyte apoptosis following MTX- injury in the rat.

Chronic arsenic exposure increases TGFalpha concentration in bladder urothelial cells of Mexican populations environmentally exposed to inorganic arsenic

Inorganic arsenic (iAs) is a well-established carcinogen and human exposure has been associated with a variety of cancers including those of skin, lung, and bladder. High expression of transforming growth factor alpha (TGF-α) has associated with local relapses in early stages of urinary bladder cancer. iAs exposures are at least in part determined by the rate of formation and composition of iAs metabolites (MAs III, MAs V, DMAs III, DMAs V). This study examines the relationship between TGF-α concentration in exfoliated bladder urothelial cells (BUC) separated from urine and urinary arsenic species in 72 resident women (18–51 years old) from areas exposed to different concentrations of iAs in drinking water (2–378 ppb) in central Mexico. Urinary arsenic species, including trivalent methylated metabolites were measured by hydride generation atomic absorption spectrometry method. The concentration of TGF-α in BUC was measured using an ELISA assay. Results show a statistically significant positive correlation between TGF-α concentration in BUC and each of the six arsenic species present in urine. The multivariate linear regression analyses show that the increment of TGF-α levels in BUC was importantly associated with the presence of arsenic species after adjusting by age, and presence of urinary infection. People from areas with high arsenic exposure had a significantly higher TGF-α concentration in BUC than people from areas of low arsenic exposure (128.8 vs. 64.4 pg/mg protein; p < 0.05). Notably, exfoliated cells isolated from individuals with skin lesions contained significantly greater amount of TGF-α than cells from individuals without skin lesions: 157.7 vs. 64.9 pg/mg protein ( p = 0.003). These results suggest that TGF-α in exfoliated BUC may serve as a susceptibility marker of adverse health effects on epithelial tissue in arsenic-endemic areas.

Increased epidermal growth factor levels in human milk of mothers with extremely premature infants.

Maternal milk is the major source of nutrients and growth-promoting substances in the first weeks of life for the majority of neonates. Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) are trophic peptides present in human milk with significant healing effects on injured gastrointestinal mucosa. Decreasing gestational age of neonates is associated with higher risk of developing gastrointestinal disorders, and human milk provides better protection against these diseases compared with formula. The aim of this study was to evaluate the concentrations of EGF and TGF-alpha in human milk collected from mothers with infants born: extremely preterm, preterm, and full term. Milk samples were collected at the end of first, second, and fourth week postpartum from each mother of infants born in one of the three gestational age groups: extremely preterm (23-27 wk, n = 16), preterm (32-36 wk, n = 16), and full term (38-42 wk, n = 15). Milk concentrations of EGF and TGF-alpha were quantified with a homologous RIA in the milk aqueous fraction. Concentrations of EGF in human milk from the extremely preterm group (23-27 wk) were significantly higher compared with values from the preterm and full-term groups throughout the first month of lactation. A similar pattern was observed with human milk TGF-alpha; however, milk TGF-alpha levels were lower than EGF. In conclusion, we have found higher concentrations of EGF and TGF-alpha in human milk of mothers with extremely preterm babies. These data may indicate the potential importance of milk-borne EGF and TGF-alpha for the development of extremely premature infants.

Influence of transforming growth factor-alpha on expression of matrix metalloproteinase-2, matrix metalloproteinase-9, and epidermal growth factor receptor gene in the mouse blastocysts.

This study was carried out to investigate the influence of transforming growth factor-alpha (TGF-alpha) on the expression of mRNA for matrix metalloproteinase-2 (MMP-2), MMP-9, and epidermal growth factor receptor (EGFR) in mouse blastocysts and the effect on the production and activation of MMP-2 and MMP- 9 during blastocyst outgrowth. Two-cell mouse embryos were cultured for 96 h in the presence or absence of various concentrations of TGF-alpha. Reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the expression of mRNA for MMP-2, MMP-9, and EGFR in in vitro cultured blastocysts. To investigate the effect on the production and activation of MMP-2 and MMP-9 during blastocyst outgrowth, the conditioned medium collected after 3 and 5 days of embryo culture were assayed for MMP activity by gelatin zymography. The relative mRNA levels of MMP-2 and MMP-9 in blastocysts treated with TGF-alpha were higher than that of the control in a concentration-dependent manner. The relative mRNA level of EGFR in blastocysts treated with TGF-alpha was higher than that of the control. In conditioned medium collected after 3 days of embryo culture, TGF-alpha induced the gelatinase activities of proMMP-9 in all groups and activated MMP-2 in the 10 and 100 ng/mL TGF-alpha treated groups. In conditioned medium collected after 5 days, TGF-alpha induced the gelatinase activities of proMMP-9 in all groups and activated MMP-9 in the TGF-alpha treated group. TGF-alpha also induced the gelatinase activities of activated MMP-2 in the 1 and 10 ng/mL TGF-alpha treated groups and the control. These results suggest that the addition of TGF-alpha to in vitro culture medium is proper to create a favorable environment for preimplantation embryo development and implantation.

P21WAF1 and TGF-α mediate parathyroid growth arrest by vitamin D and high calcium

High dietary phosphorus (P) worsens uremia-induced parathyroid (PT) hyperplasia through increases in the growth promoter transforming growth factor-alpha (TGF-alpha). In contrast, P restriction prevents PT hyperplasia by inducing the cell cycle inhibitor p21. Since 1,25(OH)2D3-antiproliferative action in various cell types involve increases in p21, we studied whether induction of p21 by 1,25(OH)2D3 or the vitamin D analog, 19-Nor-1,25(OH)2D2, could counteract the PT hyperplasia induced by high dietary P in early uremia. Normal (N) and uremic (U; 5/6 nephrectomized) female Sprague-Dawley rats were fed high P (HP), low P (LP) or high Ca (HCa) diets and administered intraperitoneally (IP) either vehicle or vitamin D metabolites for seven days, as follows: N-HP; U-HP + vehicle; U-HP + 1,25(OH)2D3 (4 ng/day); U-HP + 19-Nor-1,25(OH)2D2 (30 ng/day); U-LP; U-HCa. Serum PTH and PT gland weight assessed secondary hyperparathyroidism. Immunohistochemical quantitation of two markers of mitotic activity, Ki67 and PCNA measured PT hyperplasia. Immunohistochemical expression of PT p21 and TGF-alpha addressed potential mechanisms regulating PT cell growth. 1,25(OH)2D3 and 19-Nor-1,25(OH)2D2 were effective in suppressing both PTH secretion and PT hyperplasia induced by uremia and high dietary P independent of increases in ionized Ca. Both vitamin D compounds enhanced PT p21 expression and prevented high P-induced increases in PT TGF-alpha content. Induction of PT p21 and reduction of TGF-alpha content also occurred when uremia-induced PT hyperplasia was suppressed by high dietary Ca. In early uremia, vitamin D suppression of high P-induced PT hyperplasia and high dietary Ca arrest of PT growth involve induction of PT p21 and prevention of increases in TGF-alpha.

Follicular stage-dependent tumor necrosis factor alpha-induced hen granulosa cell integrin production and survival in the presence of transforming growth factor alpha in vitro.

The link between cell adhesion to extracellular matrix and integrin-mediated survival signals has been established in several physiological systems, and roles for the cytokines tumor necrosis factor alpha (TNF alpha) and transforming growth factor alpha (TGF alpha) have been suggested. TGF alpha stimulates fibronectin production in hen granulosa cells and is an important survival factor during follicular maturation. In contrast, the role of TNF alpha and its possible interaction with TGF alpha in the regulation of granulosa cell fate (death versus survival) during ovarian follicular development have not been fully elucidated. The object of the current study was to determine if TNF alpha and TGF alpha interact in the regulation of hen granulosa cell fibronectin and integrin content in the context of cell death and survival during follicular development. TGF alpha (0.1 or 10 ng/ml), but not TNF alpha (0.1 or 10 ng/ml), increased both cellular and secreted fibronectin content in granulosa cell cultures of F5,6 but not F1 follicles. The expression of integrin beta(3) subunit was also stimulated by TGF alpha in a follicular stage-dependent manner, and culture of F5,6 granulosa cells with TNF alpha in the presence of maximal stimulatory concentrations of TGF alpha potentiated this response. TGF alpha increased both F5,6 and F1 granulosa cell [(3)H]thymidine incorporation but not 3-(4,5-dimethylthiazol-2-yl)3,5-diphenyl tetrazolium bromide (MTT) metabolism. Although TNF alpha had no effect on [(3)H]thymidine incorporation irrespective of the presence of the growth factor, MTT metabolism was higher in F5,6 granulosa cells cultured for 24 h with both TNF alpha and TGF alpha than with either cytokine alone. Incubation of F5,6 granulosa cells for 48 and 72 h resulted in a TGF alpha-inhibited loss of cellular adhesion and detachment of granulosa cells from the growth surface. Although TNF alpha alone had no effect on cell morphology, it facilitated the reorganization of the granulosa cells into multicellular follicle-like structures in the presence of the growth factor. DNA degradation significantly increased between 0 and 72 h of culture in the absence of the cytokine but was suppressed by the addition of TGF alpha but not of TNF alpha. However, fluorometric analysis indicated that the primary type of cell death exhibited by F5,6 granulosa cells during extended culture and attenuated by the presence of TNF alpha and TGF alpha was necrosis and not apoptosis. The current study demonstrates that TNF alpha and TGF alpha interact in the regulation of granulosa cell integrin content and cell survival in vitro in a follicular stage-dependent manner. These findings suggest that follicular development is accompanied by a change in the intraovarian role of TNF alpha; it is atretogenic prior to follicular selection but prevents follicular demise during preovulatory growth.

The effect of pasteurization on transforming growth factor alpha and transforming growth factor beta 2 concentrations in human milk.

Transforming growth factor alpha (TGF-alpha) and beta 2 (TGF-beta2) are present in human milk and are involved in growth differentiation and repair of neonatal intestinal epithelia. Heat treatment at 56 degrees C has been shown effective for providing safe banked donor milk, with good retention of other biologically active factors. The purpose of our study was to determine the effect of heat sterilization on TGF-alpha and TGF-beta2 concentrations in human milk. Twenty milk samples were collected from 20 lactating mothers in polypropylene containers and frozen at -20 degrees C for transport or storage. Before heat treatment by holder pasteurization, the frozen milk was thawed and divided into 1-mL aliquots. All samples were heated in an accurately regulated water bath until a holding temperature was achieved, then held for 30 minutes using constant agitation. Holding temperature ranged from 56.5 degrees C to 56.9 degrees C. The milk was then stored at 4 degrees C overnight for analysis the following day. The concentration of TGF-alpha was measured by radioimmunoassay. Mean concentration +/- SD of TGF-alpha in raw milk samples was 119+/-50 pg/mL, range 57 to 234. The mean concentration +/- SD of TGF-alpha in heat treated samples was 113+/-50 pg/mL, range 51 to 227. TGF-alpha concentration was minimally affected by pasteurization, with an overall loss of 6.1%. Of 19 samples, 4 had increased and 15 had decreased concentrations after pasteurization (mean percent SEM: 94%+/-7% of raw milk, range 72%+/-107%). The concentration of acid-activated TGF-beta2 was measured by enzyme-linked immunosorbent assay. Mean concentration +/- SD of TGF-beta2 in raw milk samples was 5624+/-5038 pg/mL, range 195 to 15480. The mean concentration +/- SD of TGF-beta2 in heat-treated samples was 5073+/-4646 pg/mL, range 181 to 15140. TGF-beta2 survived with relatively little loss (0.6%): of 18 samples, 11 had increased and 7 had decreased concentrations after pasteurization (mean percent +/- SEM: 99.4+/-6.7% of raw milk, range 79%-120%). In conclusion, both TGF-alpha and TGF-beta2 were well-preserved in whole milk after holder pasteurization at 56.5 degrees C. The relative increase in growth factor concentration in some of the samples may be attributable to the release of that factor from the cellular and/or fat compartments into the aqueous fraction of human milk. These findings have implications regarding use of donor milk as an alternate source of growth factors and cytokines for the newborn gut when mother's milk is unavailable.

Milk-borne epidermal growth factor modulates intestinal transforming growth factor-alpha levels in neonatal rats.

Epidermal growth factor (EGF) is present in milk from various mammalian species, but its physiologic function in neonatal development remains unclear. Transforming growth factor-alpha (TGF-alpha) is a peptide structurally related to EGF, and its presence is detected in the developing small intestine of rats. The purpose of the present study was to examine the effect of milk-borne EGF on endogenous production of EGF and TGF-alpha in the small intestine of suckling rats. Neonatal rats were fed via gastrostomy either growth factor-free rat milk substitute (RMS) or RMS supplemented with EGF (100 ng/mL of RMS) from 8 to 12 d of age. Artificially reared rats were then compared with their dam-fed littermates. Animals fed the EGF-deficient diet RMS had markedly increased EGF and TGF-alpha mRNA levels in duodenum and ileum compared with dam-fed controls and significantly elevated total intestinal content of TGF-alpha peptide. Intestinal EGF content and EGF serum levels were significantly decreased in the RMS group compared with controls. The addition of EGF to the RMS diet normalized TGF-alpha mRNA levels in the duodenum and ileum, EGF mRNA levels in the ileum, and total intestinal TGF-alpha content and EGF serum levels to the levels measured in dam-fed littermates. Motility studies showed that enteral administration of EGF did not affect stomach emptying and intestinal transit. These studies indicate that exogenous milk-borne EGF modulates endogenous production of TGF-alpha in developing small intestine. It is likely that neither TGF-alpha nor EGF are solely responsible for small intestinal overgrowth of artificially reared neonatal rats.

Growth factors in expressed prostatic fluid from men with prostate cancer, BPH, and clinically normal prostates.

Although growth factors such as epidermal growth factor (EGF), transforming growth factor (TGF)-alpha, and TGF-beta are important regulators of prostate cell growth in vitro and in animal models, evidence to support their role in human prostate cancer development remains sparse. We previously showed that men without prostate cancer have concentrations of EGF and TGF-alpha in expressed prostatic fluid (EPF) that are individually distinct and stable over time. This study addressed whether growth factor levels in EPF are associated with the presence or progression of prostate cancer. We measured levels of immunoreactive EGF, TGF-alpha, and TGF-beta1 in stored EPF samples from three age-matched groups: 19 men with untreated, histologically diagnosed prostate cancer (CaP), 38 with benign prostate hyperplasia (BPH), and 19 with normal prostate glands (NPD). Median TGF-alpha was lower in the BPH group (0.45 ng/ml) than in either CaP (0.63 ng/ml) or NPD (0.58 ng/ml) groups (P = 0.03 and 0.12, respectively). For EGF, the median was lowest in the CaP group and highest in the NPD group (92.5 ng/ml vs. 175.5 ng/ml, P = 0.006). For TGF-beta1, the median level in CaP was 2.7 times higher than the median level among all controls (6.65 ng/ml vs. 2.46 ng/ml, P = 0.002). Growth factor levels were not associated with tumor stage or Gleason score. However, the single case with distant metastases had TGF-beta1 levels 23-fold higher than the CaP median. The results suggest that at the time of CaP diagnosis, EGF levels in EPF are significantly lower, and TGF-beta1 levels significantly higher, than normal. Marked overexpression of TGF-beta1 in advanced CaP might be reflected in extremely high EPF levels.

Immunolocalization and quantitation of transforming growth factor alpha in hydatidiform mole.

Complete hydatidiform mole (CHM), a condition related to abnormal gestation, occurs predominantly in the young reproductive age group and has a high prevalence rate in the Trivandrum region, occurring in 1.2% of deliveries. Transforming growth factor alpha (TGF-alpha) is an important growth regulatory molecule, the location and function of which at the human fetomaternal interface in CHM remains to be determined. The present study examined the presence of TGF-alpha in the normal and complete molar placenta and decidua throughout gestation. A total of 149 complete molar placental tissue samples and 96 normal placental tissue samples were evaluated for TGF-alpha expression by immunohistochemistry and 50 each of CHM and normal placental tissue for TGF-alpha concentration by radioimmunoassay. The peptide was localized immunocytochemically with a monoclonal anti-TGF-alpha antibody on paraffin-embedded tissue using the avidin-biotin complex peroxidase technique with aminoethyl carbazole as the chromogen. In molar placenta, villous trophoblast cells (syncytiotrophoblasts and cytotrophoblasts) showed intense cytoplasmic staining at all gestational ages compared to normal placenta of the same gestational age. The tissue concentration of TGF-alpha was highly overexpressed in the molar placenta (10-1000 fold) compared to that in the normal placenta. The results indicate that TGF-alpha is present in trophoblasts throughout human gestation and may provide additional growth advantage to maintenance of the hyperproliferative condition in trophoblastic tumors.

TGF-alpha exerts biphasic effects on estrogen--and phytoestrogen-mediated gene expression in breast cancer cells.

Transforming growth factor-alpha (TGF-alpha) contributes to the progression of mammary carcinogenesis in part through synergistic augmentation of estradiol (E2) action. To investigate this further, we sought to determine (1) whether the duration of TGF-alpha treatment might influence the nature of the TGF-alpha/E2 interaction, and (2) whether TGF-alpha would behave in a similar manner when combined with phytoestrogens. To this end, we transfected T47-D breast cancer cells with an estrogen-responsive reporter and then treated the cells (for 4-48 h) with varying concentrations of TGF-alpha, E2, the antiestrogen 4-hydroxy-tamoxifen (HOT), and/or one of three phytoestrogens. Our findings revealed that TGF-alpha has short-term synergistic and long-term inhibitory effects on E2- and phytoestrogen-regulated gene expression. Furthermore, this secondary inhibition of E2 action by TGF-alpha was similar in magnitude to that imposed by HOT. These findings demonstrate a novel role for TGF-alpha and invite reevaluation of current models regarding TGF-alphas interactions with E2 in breast cancer cells. Our results also raise the possibility that phytoestrogens, which interact with TGF-alpha in a manner conceptually identical to that of E2, may subserve a regulatory function in breast cancer cells.

Effects of epidermal growth factor on neonatal pancreatic growth in the guinea pig.

EGF and/or transforming growth factor-alpha (TGF-alpha) are likely to be important in the rapid pancreatic growth that occurs in the neonatal guinea pig. Rapid pancreatic growth is observed during the neonatal period in the guinea pig. The growth factors that are involved are not known but may include members of the EGF family. Mini-osmotic pumps were implanted on the day of birth for continuous infusion of EGF (30 microgram/d). Pancreatic DNA, RNA, and protein contents were determined at 4 and 15 d, along with wet weights of the pancreas, duodenum, jejunoileum, colon, and gallbladder. Pancreatic EGF and TGF-alpha concentrations were measured in adult controls, in control neonates at 1, 4, 8, and 15 d, and also at 4 and 15 in guinea pigs receiving either EGF or the cholecystokinin receptor antagonist devazepide (25 nmol/kg/h). EGF infusion significantly increased the weight of the stomach and duodenum at 4 d and all the gastrointestinal organs, including the pancreas, at 15 d. Exogenous EGF increased pancreatic DNA, RNA, and protein content at 4 and 15 d. Endogenous EGF and TGF-alpha concentrations in the pancreas were significantly higher at birth than in adults (P < 0.001) and P < 0.01, respectively) and declined during the first 2 wk postpartum. At 15 d, EGF concentrations remained significantly higher than adult levels (P < 0.01), but TGF-alpha concentrations had declined to adult values. Infusion of EGF decreased concentrations of endogenous EGF in the pancreas at 4 and 15 d (both P < 0.05) and decreased TGF-alpha concentrations at 4 d (P < 0.001). Devazepide infusion caused a significant decrease in endogenous pancreatic EGF concentrations at 15 d (P < 0.05).

Presence of transforming growth factor alpha and epidermal growth factor in human ovarian tissue and follicular fluid.

Intra-ovarian regulation of follicular maturation is modulated by various factors. Among these, growth factors are important local actors. We examined the immunohistochemical localization of transforming growth factor alpha (TGF-alpha), epidermal growth factor (EGF) and epidermal growth factor receptor (EGF-R) in 18 human ovaries. The concentration of TGF-alpha and EGF in follicular fluid was measured by ELISA. TGF-alpha was detected in oocytes of primordial and early preantral follicles. Furthermore, staining was observed in granulosa cells of preantral follicles and in theca cells of preantral, antral and preovulatory follicles. EGF showed a similar distribution as TGF-alpha. Atretic follicles were strongly positive for TGF-alpha and EGF. In the corpus luteum, theca lutein cells were strongly positive for TGF-alpha and EGF. Immunoreactivity for EGF-R was observed only in the granulosa cells of antral follicles. Follicular fluids from patients undergoing in-vitro fertilization (IVF) were examined for their content of TGF-alpha and EGF. TGF-alpha was detected in 37% of the samples. The concentration ranged from 43 pg/ml to 602 pg/ml. EGF was not detected in any of the follicular fluids tested. These observations support the participation of EGF/TGF-alpha in follicular maturation. Furthermore, the presence of TGF-alpha in follicular fluid and the simultaneous absence of EGF suggests that TGF-alpha plays a more pronounced role than EGF in oocyte maturation during late follicular phase.

Elevated transforming growth factor-alpha levels in bronchoalveolar lavage fluid of patients with acute respiratory distress syndrome.

The acute respiratory distress syndrome (ARDS) frequently results in a fibroproliferative response that precludes effective alveolar repair. Transforming growth factor-alpha (TGF-alpha), a potent epithelial and mesenchymal cell mitogen, may modulate the response to lung injury. In this study, we determined whether bronchoalveolar lavage fluid (BALF) concentrations of TGF-alpha are increased during the first 2 wk after the onset of ARDS and, if so, whether increased TGF-alpha levels in lavage fluid are associated with increased levels of procollagen peptide III (PCP III), a biological marker of fibroproliferation, and with increased fatality rates. We enrolled 74 consecutive patients with ARDS prospectively identified on admission to the intensive care unit of a tertiary care hospital, and 11 patients with chronic interstitial lung disease. Thirteen healthy volunteers served as control subjects. TGF-alpha concentrations were measured in BALF recovered on Days 3, 7, and 14 after the onset of ARDS (total of 130 lavage samples). TGF-alpha was detected in the lavage fluid of 90% of patients with ARDS (67 of 74), and in 100% of patients with idiopathic pulmonary fibrosis (IPF) (10 of 10), but in none of 13 normal volunteers. At each day tested, the median lavage TGF-alpha level of patients with ARDS was significantly higher than that of normals. The overall fatality rate was 45% (33 of 74 patients). In a univariate analysis, the median TGF-alpha levels in nonsurvivors were 1.5-fold higher at Day 7 (p = 0.06) and 1.8-fold higher at Day 14 (p = 0.048). The fatality rate was 4 times higher (CI 1.6, 17.5) for patients with both increased lavage TGF-alpha and PCP III concentrations at Day 7 than for patients with low TGF-alpha and PCP III values, indicating a synergistic relationship between TGF-alpha and PCP III. We conclude that increased levels of TGF-alpha in BALF are common in patients with ARDS and that lavage TGF-alpha is associated with a marker of the fibroproliferative response in sustained ARDS.

TGF-alpha, EGF, and their cognate EGF receptor are co-expressed with desmin during embryonic, fetal, and neonatal myogenesis in mouse tongue development.

The developing mouse tongue provides a model for discrete patterns of morphogenesis during short periods of embryonic development. Occipital somite-derived myogenic cells interact with cranial neural crest-derived ecto-mesenchymal cells to form the musculature of the tongue. The biochemical signals that control close range autocrine and/or paracrine signaling processes required to establish the fast-twitch complex tongue musculature are not known. The present study was designed to test the hypothesis that desmin, epidermal growth factor (EGF), and transforming growth factor-alpha (TGF alpha) and their cognate receptor, epidermal growth factor receptor (EGFr), are co-expressed during tongue myogenesis and define specific developmental stages of tongue muscle cell differentiation. To test this hypothesis, we performed studies to analyze the timing, position, and concentration of desmin, TGF alpha, EGF, and EGFr from embryonic day 9 (E9) through birth in Swiss Webster mouse tongue development. Desmin, TGF alpha, EGF, and EGFr co-localized to cells of myogenic lineage in the four occipital somites and subsequently in myoblasts and myotubes from E9 through E17. By newborn stage, desmin is localized to discrete regions in myofibers corresponding to Z-line delimiting sarcomeres, and A-band within sarcomeres; immunostaining for desmin, TGF alpha, and EGF persisted in differentiated myotubes and striated skeletal muscle. Desmin increased from 0.01% at E11 to 0.51% of the total protein by E17 and at birth. Concomitantly, the patterns and increases in TGF alpha, EGF, and EGFr showed significant increases during the same developmental period. The temporal and positional co-localization of TGF alpha, EGF, and EGFr support the hypothesis that autocrine and paracrine regulation of desmin by actions of growth factor ligand and receptor defines critical stages of tongue myogenesis.