Expression of transforming growth factor-β type II receptor mRNA in embryonic and adult rat kidney

Summary: The transforming growth factor-β (TGF-β) family of growth factors regulates cell proliferation, differentiation, extracellular matrix synthesis and angiogenesis in many developing tissues. Transforming growth factor-β1 was recently shown to affect the branching of ureteric epithelium and nephron formation in cultured rat metanephroi. As the TGF-β type II receptor is specific for the TGF-β family, the present study used in situ hybridization to localize mRNA for this receptor in metanephroi from Sprague-Dawley rat embryos. Transforming growth factor-β type II receptor mRNA was located in ureteric duct epithelium, undifferentiated mesenchymal cells in the nephrogenic zone, vesicles, comma-shaped bodies and S-shaped bodies. In some S-shaped bodies, TGF-β type II receptor mRNA was not expressed in the lower limb, which subsequently forms the renal corpuscle. Expression was not observed in capillary loop stage glomeruli and maturing glomeruli, or in proximal tubules and interstitial cells. In adult rat kidney, TGF-β type II receptor mRNA was expressed in cortical collecting ducts and distal tubules but not in glomeruli or proximal tubules. These findings demonstrate that the prominent expression of TGF-β type II receptor mRNA decreases as glomeruli and tubules develop. Expression then remains undetectable in adult glomeruli and proximal tubules. the developmentally-regulated expression of this receptor suggests a key role in glomerular and nephron development.     

膀胱移行细胞癌表皮生长因子及其受体表达和意义

目的 探讨表皮生长因子(EGF)、EGF受体(EGFR)在膀胱移行细胞癌(BTCC)中的表达及意义。方法 用免疫组化ABC法对56例BTCC标本和20例癌旁组织EGF、EGFR进行研究。结果 20例癌旁正常膀胱组织中EGF，EGFR几乎不表达；56例ETCC标本中EGF，EGFR表达明显，与正常组比较有显著性差异(P＜0．01)，不同分期和分级BTCC中的阳性表达率均存在显著性差异(P＜0．05)。结论 EGF，EGFR的检测可以作为判断BTCC预后的一个指标。     

The effect of different immunosuppressive regimens on TGF-β1 expression in kidney transplant patients

Transforming growth factor (TGF)-beta1 is a key profibrogenic cytokine associated with the pathogenesis of chronic allograft nephropathy (CAN). The primary aim of this study was to evaluate TGF-beta1 expression in protocol kidney graft biopsy in patients treated with different immunosuppressive regimens. Protocol kidney graft biopsies were carried out in 77 patients with stable graft function at 1 year after kidney transplantation, treated with a triple-drug regimen based on cyclosporin A (CyA; n = 49) or tacrolimus (TAC; n = 28). Morphological findings were assessed using the Banff 97 classification. TGF-beta1 expression was analysed using immunochemistry, and semiquantitatively scored in different renal structures (total score 0-18). Clinical data were analysed at the time of biopsy, and 12 months thereafter. No significant relation was found between the used immunosuppressive regimen and the histomorphological picture in the graft. TGF-beta1 expression within graft tissue was significantly higher in patients treated with CyA when compared with TAC (9.94 +/- 4.2 vs. 5.0 +/- 3.2; P < 0.001). Serum creatinine and glomerular filtration rate (GFR; Cockroft-Gault calculation) were comparable in both groups but, in the course of the next 12 months, GFR significantly decreased only in the CyA-treated group (from 1.03 +/- 0.33 to 0.96 +/- 0.37 ml/s) while not changing in the TAC-treated group. Patients treated with TAC had significantly lower diastolic blood pressure and serum cholesterol. The significantly lower TGF-beta1 expression in 1-year protocol kidney graft biopsy in TAC-treated patients with stable renal function, and the different development of graft function in both groups suggest a possible benefit of TAC for long-term graft acceptance.     

Extracellular matrix, growth factors and their interactions in the pathogenesis of diabetic kidney disease

Summary: The accumulation of extracellular matrix (ECM) within the glomerulus is the ultrastructural hallmark of diabetic nephropathy and is directly linked to the declining renal function. the pathogenesis of these ECM changes in diabetes is not well understood but is likely to involve interaction between cells, growth factors, structural proteins and cell receptors for these molecules. Recent advances in cellular and molecular biology have highlighted the complex nature of the molecular interactions which may lead to glomerulosclerosis in diabetes.     

Stimulatory effect of EGF and inhibitory effect of sialoadenectomy on growth of an EGF receptor-hyperproducing human gastric cancer xenograft in nude mice

We recently established epidermal growth factor (EGF) receptor-hyperproducing human gastric cancer xenografts in nude mice. The present study was designed to examine whether the growth of a xenograft having 1,098 ±276fmol/mg protein of EGF receptor would either be stimulated by the administration of EGF or inhibited by the removal of the submandibular glands (sialoadenectomy) which contain a large amount of EGF. A miniosmotic pump containing 2 g or 20 g of EGF was implanted on the back of the animals in the EGF stimulation experiments. The tumor growth was stimulated by the administration of EGF (P < 0.01), and the doubling time of the tumor was reduced relative to the controls (P < 0.01). Both the mitotic indices and the bromodeoxyuridine (BrdU)-labeling indices of the tumor were higher than those of the controls (P < 0.01). Tumor growth inhibited by the sialoadenectomy (P < 0.05) while the tumor doubling time was prolonged compared with the sham-operated mice (P < 0.05). These results suggest that the growth of a human gastric cancer xenograft may be modulated by EGF.     

Expression of human epidermal growth factor and its receptor in esophageal cancer

The expression of human epidermal growth factor (hEGF) was examined immunohistochemically in 86 esophageal cancer lesions, comprising 67 primary tumors and 19 metastatic lymph nodes. In the normal esophagus, the parabasal and intermediate cell layers showed a weak expression of hEGF, however, hEGF-positive tumor cells were detected in 62 (92.5 per cent) of the 67 primary esophageal carcinomas and in 18 (94.7 per cent) of the 19 metastatic lymph nodes. In this study, the immunoreactivity of hEGF was classified into 4 grades according to the number of stained tumor cells. A significant correlation was observed between the histologic type and the grade of hEGF immunoreactivity (Chisquare test, p<0.01). hEGF immunoreactivity in well differentiated squamous cell carcinomas was significantly higher than in other squamous cell carcinomas, although there were no correlations between other pathological findings and hEGF immunoreactivity. Patients with hEGF immunoreactivities of grades II or III had much worse prognoses than those with grades 0 or I (p<0.05). In 22 esophageal carcinomas and 10 normal esophageal mucosae, EGF receptor (EGFR) contents were measured by the competitive binding assay. The average EGFR content (101.3±35.7 fmol/mg protein, mean±SE) of the esophageal carcinomas was significantly higher than that (5.3±1.2) of the normal esophageal mucosae (p<0.05). Moreover, in hEGF negative tumors, EGFR contents were lower than in hEGF positive tumors. These results suggest that hEGF and EGFR show increased production in squamous cell carcinomas and could to be useful prognostic factors in patients with esophageal cancer.     

Expression of galectin-3 and its regulation in the testes

Although spermatogenesis is a complex process under hormonal control, which includes mainly follicle stimulating hormone (FSH) and androgens, little is known about the intra-testicular mediators of these hormones. In the present study, galectin-3 (Gal-3) expression has been identified in human, rat and porcine testes where it is under hormonal control. Gal-3 is present in Sertoli cells and appears to be absent in human and (probably) in rat germ cells. Gal-3 expression was evidenced in the testes, in terms of both mRNA and protein (31 kDa). Gal-3 expression in cultured porcine Sertoli cells was shown to be under the positive control of FSH as well as of two cytokines epidermal growth factor (EGF) and tumour necrosis factor-alpha (TNF-alpha). Gal-3 expression in Sertoli cells is also potentially under the control of mature germ cells as an increased expression was observed in adult rat testes depleted in spermatocytes or spermatids. Although the function of testicular Gal-3 remains to be investigated, a potential role of Gal-3 in germ cell survival/regeneration is suggested based on its increased expression 1 month after a transient germ cell death process triggered by 10 days of treatment with the antiandrogen flutamide. Finally, although in the normal human testes, Gal-3 is exclusively located in the Sertoli cell cytoplasm, a nuclear localization is observed in the infertile testes. Together, the present findings have shown that (i) Gal-3 is expressed in the porcine, rat and human Sertoli cells; (ii) Gal-3 is under the positive control of FSH as well as of EGF and TNF-alpha and possibly of adult germ cells. These observations are compatible with a potential pro-survival role of Gal-3 in the testes.     

Expression of the epidermal growth factor receptor in fetal kidney

Formation of the human kidney begins at the 6th week of fetal life when the first generations of nephrons are generated from foci of metanephric mesenchyme through contact with the branches of the ureteric bud. This process requires a proliferative burst which must be tightly regulated by local signals. In this report, we review the evidence that the epidermal growth factor receptor molecule is an important arbiter of these events.     

Clinical significance of EGF and EGFR expression changes in cryptorchid boys

Aim: To explore the changes of epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) expressions in cryptorchid children and their clinical significance. Methods: The level of serum EGF was measured by radioimmunoassay (RIA) and the expression of EGFR by immunohistochemistry. Results: (1) The level of serum EGF was significantly lower in cryptorchid children than in normal subjects at age group of 59 years (P<0.01) and 10-14 years (P<0.01), (2) The level of EGF was significantly lower in boys with impalpable testis than in those with extracanalicular and intracanalicular testes (P<0.01), (3) The serum EGF level increased significantly 6 months after orchiopexy (P<0.05), (4) The EGFR expression in testicular Leydig's cells was lower in 2-4 year-old boys than in those over 5 years (P<0.05) and (5) the EGFR expression was less positive in the impalpable group and the intracanalicular group than that of the extracanalicular group (P<0.01). Conclusion: The EGF and EGFR expr essions may co     

Gene Expression of TGF-α, EGF and IL-6 in Cultured Renal Tubular Cells and Renal Cell Carcinoma

Background: Renal cell carcinoma (RCC) is thought to arise from the renal tubular cells (RTC). Assuming that proliferating RTC imply a premalignant change of RTC into RCC, messenger RNA expressions of growth factors in cultured RTC were compared to both cultured and frozen noncultured RCC.
Methods: The expression of transforming growth factor-alpha (TGF-α), epidermal growth factor (EGF), EGF receptor (EGFR) and Interleukin-6 (IL-6) were studied in surgically obtained RCC (n=17), cultured RCC (n=10), and autologous cultured RTC (n = 15). Quantitation of the PCR product was performed using a computer image analyzer which evaluated the intensity of each cytokine relative to β-actin.
Results: TGF-α, EGFR and IL-6 were detected in most of the cultured RTC, and both cultured and noncultured RCC were also expressed at high levels. In contrast to a high positivity of TGF-α, EGF was not strongly positive in all specimens.
Conclusions: Our results show that there is a predominant autocrine production of TGF-α in RCC and RTC, suggesting that TGF-α plays a distinct role in the proliferation of these cells. These studies also indicate that the mechanisms of proliferation and cytokine production of RCC and RTC are similar.     

Androgenic and antiandrogenic control on epidermal growth factor,epidermal growth factor receptor,and androgen receptor expression in human prostate cancer cell line LNCaP

Both androgen and antiandrogen treatments enhance the proliferation rate of the hormone-dependent prostate cancer cell line LNCaP, expressing a mutated androgen receptor (AR). We studied the modification of the expression of epidermal growth factor (EGF), of its receptor (EGF-R), and of androgen receptor (AR) in the LNCaP cell line, under basal conditions and during androgen (R1881) and antiandrogen hydroxy-flutamide (OH-FLU) treatment. After prolonged R1881 administration, a marked increase of EGF release was observed, completely blocked by the addition of OH-FLU. The Scatchard plot analysis of EGF-R binding revealed two classes of binding sites with high and low affinity. The administration of OH-FLU alone or combined with R1881 did not modify the affinity constants, while the low-affinity component disappeared after androgen administration. Both androgen and antiandrogen administration led to a significant increase of the EGF-R high-affinity component. AR mRNA and protein levels were downregulated by R1881 treatment. Following OH-FLU administration, AR mRNA was slightly downregulated, and there was not a strict parallelism between AR mRNA levels and AR binding capacity. When combined with R1881, OH-FLU partially counteracted the androgen-induced AR downregulation. Our data show that EGF-R binding capacity is the only parameter constantly raised in cell proliferation with respect to quiescent cells, and highlights the nonunivocal action of OH-FLU on androgen-induced effects.     

Intercellular adhesion molecule-1 and tumour necrosis factor-α expression in human glomerulonephritis

Summary: The relationship between renal expression of intercellular adhesion molecule-1 (ICAM-1), glomerular hypercellularity, renal function and renal tumour necrosis factor-α (TNF-α) expression was examined by immunohistochemistry staining in 64 cases of human glomerulonephritis. Glomerular anti-ICAM-1 antibody staining was increased in most cases of IgA nephropathy and lupus nephritis, but was unchanged compared to normal in membranous nephropathy and minimal change disease, and reduced in glomerular sclerosis. However, when taken together, patients with mild or no glomerular hypercellularity (group A) showed normal ICAM-1 expression, those with moderate to severe hypercellularity (group B) had increased glomerular ICAM-1 expression (P<0.001), while those with glomerular sclerosis (group C) had reduced glomerular ICAM-1 expression. Patients in groups B and C also showed a significant increase in tubular ICAM-1 expression (P<0.01) and interstitial infiltration of ICAM-1 ⁺ cells (P<0.001). Indeed, tubular ICAM-1 expression correlated with decreased creatinine clearance (r= -0.352; P<0.05). In situ hybridization demonstrated that increase in tubular ICAM-1 staining was due to de novo gene expression, rather than absorption of soluble ICAM-1 from the lumen. Focal expression of tumour necrosis factor-α was seen in areas of leucocyte infiltration and strong ICAM-1 expression. Indeed, TNF-α staining correlated with increased renal ICAM-1 expression in both glomerular and tubulointerstitial compartments (r=0.81; P<0.01). to confirm that TNF-α can directly stimulate renal ICAM-1 expression, TNF-α was shown to transiently increase ICAM-1 mRNA synthesis for 4-8 h and cause a progressive increase in ICAM-1 protein on the surface of cultured human mesangial cells. In summary; (i) increased glomerular ICAM-1 expression was restricted to cases of moderate to severe hypercellularity; (ii) tubular ICAM-1 expression correlated with both creatinine clearance and interstitial infiltration of ICAM-1⁺ cells; and (iii) TNF-α expression was shown to correlate with the degree of renal ICAM-1 expression, suggesting that local TNF-α plays an important role in the up-regulation of ICAM-1 in human glomerulonephritis.     

Effect of tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) on human sperm motility, viability and motion parameters

Male genital tract infections and non-specific inflammatory conditions may be associated with unexplained infertility. Previous studies have shown the presence of cytokines such as tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in the semen of infertile men. However, the mechanism of effect of these cytokines on human sperm function is still controversial. The present study was undertaken to investigate the in-vitro effects of TNF-α and IFN-γ on human sperm motion, viability and the hypoosmotic swelling test (HOST).
Washed spermatozoa from normal volunteers ( n =9) were incubated in the presence/absence of TNF-α (1 μg/mL) plus IFN-γ (0.1 μg/mL). Sperm motility, viability, HOST, and video sequences were recorded at different time intervals (0, 30, 60 and 180 min). Sperm motion parameters were analysed using computer-assisted semen analysis. There was a time-dependent negative effect of TNF-α plus IFN-γ on sperm motility, viability, HOST, and lateral-head displacement (ALH). The maximum decrease was observed between 60 and 180 min for sperm motility (50.8 ± 5.6%), viability (52.8 ± 4.0%), HOST (38 ± 2%) and ALH (4.7 ± 0.1 μm) compared to control samples (62.2 ± 2.8, 62.4 ± 2.9, 58 ± 4, and 5.3 ± 0.4, respectively; All p  < 0.05). There was no significant effect on sperm straight-line velocity and mean linearity when compared to control.
These data suggest that the common inflammatory cytokines TNF-α plus IFN-γ have only partial detrimental effects on sperm motility, viability, membrane integrity and lateral head displacement, which may contribute to the poor fertilizing potential of human spermatozoa during inflammatory conditions.     

Myofibroblast Transdifferentiation in Obliterative Bronchiolitis: TGF-β Signaling Through Smad3-Dependent and -Independent Pathways

We have shown that Smad3, an intracellular signal transducer for transforming growth factor-beta1 (TGF-beta1), is required to elicit the full histological manifestations of obliterative airway disease in a tracheal transplant model. This suggests that chronic allograft rejection results in TGF-beta1-induced Smad3 activation that leads to airway obliteration through fibroproliferation and increased matrix deposition. In other systems, these latter events are causally related to the transdifferentiation of fibroblasts into myofibroblasts, but their role in obliterative bronchiolitis (OB) after lung transplantation is unknown. We confirmed the presence of myofibroblasts inside affected airways associated with experimental OB using immunohistochemistry. Studying airway fibroblasts in vitro, we observed increased myofibroblast transdifferentiation in response to TGF-beta1, evidenced by increased alpha-smooth muscle actin mRNA and protein expression. In Smad3-null fibroblasts, TGF-beta1 induction of myofibroblast transdifferentiation was greatly diminished but not abolished, suggesting the presence of Smad3-independent pathways. Further studies revealed that small molecule inhibitors of p38 (SB203580) and MEK/ERK (U1026) further reduced the remaining effect of TGF-beta1 in Smad3-deficient fibroblasts. Together, these studies suggest that in chronic allograft rejection, TGF-beta1 stimulates myofibroblast transdifferentiation through Smad3-dependent and -independent signals, contributing to the excessive matrix deposition that characterizes obliterative bronchiolitis.     

The expression of mRNA for tumour necrosis factor-α increases in the obstructed kidney of rats soon after unilateral ureteral ligation

Summary: Cytokines, including transforming growth factor (TGF)-β1, contribute to the tubulointerstitial fibrosis of ureteral obstruction. Tumour necrosis factor (TNF)-α, a proinflammatory cytokine produced by multiple cells including macrophages and resident renal cells, has a role in inflammatory cell recruitment in glomerular injury. We measured TNF-α mRNA in the renal cortex of rats at different times after the onset of unilateral ureteral obstruction (UUO) and determined whether angiotensin II (AngII) inhibition or total body irradiation affects the mRNA levels of TNF-α. Rats were killed at 1, 2, 4, 24, 72 and 120h after UUO. Levels of TNF-α mRNA increased significantly in the obstructed kidney at 1h (X 2), 2h (X 2.7), 4h (X 3.6), 24h (X 2.7), 72h (X 1.8) and 120h (X 2.8) after ureteral ligation when compared to the contralateral kidney of the same animals or to control (normal) kidneys. Tumour necrosis factor-α mRNA increased in renal cortical tubules but not in glomeruli. Treatment with enalapril, an angiotensin-converting enzyme (ACE) inhibitor, before and after UUO decreased TNF-α mRNA levels in the obstructed kidney by about 40% at 4h after the onset of UUO, but at 120h there was no difference in TNF-α levels in the obstructed kidney of treated and untreated animals. Total body irradiation, which depletes macrophages in the obstructed kidney, did not prevent the upregulation of TNF-α mRNA expression at 4 h after UUO. Thus, TNF-α may have a role in initiating tubulointerstitial injury in the obstructed kidney. Leucocytes infiltrating the renal interstitium of the obstructed kidney do not appear to contribute to the increased mRNA expression of TNF-α. Angiotensin II may contribute, at least in part, to the early increased expression of TNF-α mRNA in the obstructed kidney.     

Interleukin-1α and tumour necrosis factor-α modulate the production of monocyte chemoattractant protein-1 by cultured human glomerular visceral epithelial cells

Summary: Mediators released by glomerular macrophages may stimulate glomerular visceral epithelial cells (GVEC) to produce cytokines, growth factors or extracellular matrix components. This study describes that human GVEC produce monocyte chemoattractant protein-1 (MCP-1), a monocyte-specific chemotactic factor, and the effects of interleukin-lα (IL-1α) and tumour necrosis factor-α (TNF-a) on the production of MCP-1 by GVEC.
We observed that the intensity of MCP-1 staining in GVEC is stronger in membranous nephropathy and glomerulosclerosis than in normal kidneys. Various cell lines of GVEC produced significant amounts of MCP-1, as assessed by inhibition radio-immunoassay. the presence of IL-1α and TNF-α during culture of GVEC enhanced the production of MCP-1 in a dose- and time-dependent manner. Glomerular visceral epithelial cells in culture express mRNA for MCP-1 and the expression is upregulated 2.0- and 1.4-fold in the presence of optimal concentration of IL-1α and TNF-α, respectively. De novo synthesis of MCP-1 is supported by the observation that MCP-1 production is fully inhibited by cydoheximide. Monocyte chemoattractant protein-1 isolated from GVEC supernatants exhibits a molecular size of 12 and 10 kDa as determined by gel filtration chromatography. Both sizes of MCP-1 is chemotactically active for monocytes.
This study shows increased MCP-1 production by cultured human GVEC after stimulation with the inflammatory cytokines IL-1α and TNF-α. the expression of MCP-1 in GVEC was found to be upregulated in membranous nephropathy and glomerulosclerosis. These findings suggest that MCP-1 may be involved in glomerular injury in these diseases. the possible role of MCP-1 in the pathogenesis of human glomerulonephritis is discussed.     

转化生长因子调控表皮生长因子受体在雄激素非依赖型前列腺癌细胞中表达的意义

目的 :探讨转化生长因子 (TGF)α对前列腺癌雄激素非依赖型细胞系中表皮生长因子受体 (EGFR)表达的调控。　方法 :采用逆转录 多聚酶链式反应和Western印迹法对TGFα刺激前列腺癌雄激素非依赖型细胞系PC3、ARCaP后EGFRmRNA表达及其蛋白水平进行定量分析。　结果 :TGFα引起PC3、ARCaP的EGFRmRNA表达升高 ,分别为 5 .0 1± 0 .4 5和 9.0 5± 0 .6 3,明显高于对照组 (P <0 .0 5 )。PC3细胞系TGFα治疗后EGFR蛋白水平为 2 .2 8±0 .5 3,明显高于对照组 (P <0 .0 5 ) ;而ARCaP细胞系TGFα治疗后EGFR仅为 1 .2 4± 0 .2 2 ,和对照组比较无差别 (P >0 .0 5 )。　结论 :TGFα可以明显提高前列腺癌细胞的EGFR表达量 ;TGFα EGFR自分泌环参与雄激素非依赖型前列腺癌的形成     

Changes in gene expression of growth factors and their receptors during castration-induced involution and androgen-induced regrowth of rat prostates

To find candidates for the mediator of the growth-promoting action of androgen in rat prostates, the changes in the steady-state levels of mRNAs coding for several growth factors and their receptors were examined by Northern blot analysis during castration-induced involution, and subsequent regrowth induced by androgen in the ventral and dorsolateral lobes. The changes in the growth factor systems and a typical secretory protein in the ventral lobe were similar to, but more prominent than, those in the dorsolateral lobe, showing the higher androgen dependency of the ventral lobe. Among the growth factors and their receptors investigated, only epidermal growth factor (EGF) showed apparent positive androgen dependency: EGF mRNA content in the ventral lobe decreased to about 30% of the normal level within 24 hr after castration, and increased, attaining about 200–300% of the normal level 3–5 days after androgen administration to castrated rats. mRNAs coding for all other factors examined, i.e., transforming growth factor-α (TGF-α), EGF receptor, basic fibroblast growth factor (bFGF), keratinocyte growth factor (KGF), FGF receptor 1, TGF-β1, TGF-β type II receptor, hepatocyte growth factor (HGF), and c-MET/HGF receptor, increased after castration in greater or lesser degree, and after a brief pause or a decrease some of them increased again attaining a second peak 3–5 days after androgen replacement. The second increase was evident in TGF-α, EGF receptor, KGF, and c-MET mRNAs. These results indicate the possibility that multiple growth factor-receptor systems participate in the androgen-dependent regrowth of castrated rat prostates. © 1996 Wiley-Liss, Inc.