Characterization of Keratinocyte Growth Factor and Receptor Expression in Human Pancreatic Cancer

Keratinocyte growth factor (KGF) is an angiogenic and mitogenic polypeptide that has been implicated in cancer growth and tissue development and repair. Its actions are dependent on its binding to a specific cell-surface KGF receptor (KGFR), which is encoded by the fibroblast growth factor (FGF) receptor type II (FGFR-2) gene. In the present study, we compared the immunohistochemical localization of KGF and KGFR/FGFR-2 in the normal and cancerous pancreas using specific antibodies that recognize KGF and KGFR/FGFR-2 and examined the expression of KGF, KGFR, and FGFR-2 in human pancreatic cancer by in situ hybridization with the corresponding riboprobes. In the normal pancreas, KGF immunoreactivity was present principally in the islet cells, whereas KGFR/FGFR-2 immunoreactivity was present both in the islet and ductal cells. In the pancreatic cancers, moderate KGF and moderate to strong KGFR/FGFR-2 immunoreactivity was present in many of the cancer cells. Furthermore, the ductal and acinar cells adjacent to the cancer cells exhibited moderate to strong KGF and KGFR/FGFR-2 immunoreactivity. By in situ hybridization, KGF, KGFR, and FGFR-2 were overexpressed and co-localized in the cancer cells within the pancreatic tumor mass but were even more abundant in the acinar and ductal cells adjacent to the cancer cells. These findings indicate that KGF, KGFR, and FGFR-2 are overexpressed in both the cancer cells and the adjacent pancreatic parenchyma and raise the possibility that KGF may act in an autocrine and paracrine manner to enhance pancreatic cancer cell growth in vivo.     

MiR-150-5p inhibits the proliferation and promoted apoptosis of pancreatic cancer cells北大核心CSCD

Objective: To investigate the role of miR-150-5p in cell proliferation and apoptosis in human pancreatic cancer cell lines. Methods: The expression of miR-150-5p in pancreatic cancer was detected by real time qPCR analysis in 11 pairs of pancreatic cancer tissue and matched adjacent normal tissue samples and in 4 pancreatic cancer cell lines. PANC-1, MIA PaCa-2, BxPC-3 and AsPC-1 cells were transfected with chemically synthesized MiR-150-5p mimics, and CCK-8 assays was then performed to assess cellular functions. To fully understand the mechanisms by which miR-150-5p exerted its function, cell cycle analysis was performed on MIA PaCa-2 and PANC-1 cells 48 hours after transfection, by incubating with propidium iodide (PI) and subsequently analyzed by fluorescence-activated cell sorting (FACS). Apoptosis assay was performed on MIA PaCa-2 and PANC-1 cell lines 24 hours after transfection using the Annexin V-FITC Apoptosis Detection Kit I (BD Biosciences) and analyzed by FACS. Results: The expression of miR-150-5p was consistently lower in the pancreatic cancer tissues than in normal tissues,and the miR-150-5p was also down-regulated in pancreatic cancer cell lines (P < 0. 05). MiR-150-5p mimics transfection significantly raised the expression level of miR-150-5p mRNA in PANC-1 and MIA PaCa-2 (P <0. 01). The CCK-8 proliferation assay showed that cell growth was reduced in 4 pancreatic cancer cell lines (AsPC-1, BxPC-3, MIA PaCa-2, PANC-1) of miR-150-5p transfected cells compared with NC-transfected cells. The inhibition rates were 50. 7%,48. 6%,30. 8% and 42. 3%, respectively (P <0. 01). The apoptotic rate was increased in cells transfected with miR-150-5p mimics (P < 0. 01). The cell cycle analysis in MIA PaCa-2 indicated that miR-150-5p treatment induced cell cycle arrest in G1 phase with a significant increase in the percentage of cells in G, phase (P < 0. 01), and a reduction of the S-phase cell population in MIA PaCa-2 and PANC-1 (P<0.01). Conclusions: MiR-150-5p is down-regulated in pancreatic cancer. Overexpression of miR-150-5p inhibits cell proliferation, blocked the cell cycle, but promotes cell apoptosis in pancreatic cancer cells.     

microRNA-137 modulates pancreatic cancer cells tumor growth,invasion and sensitivity to chemotherapy

Background: We intended to investigate the role of microRNA 137 (miR-137) in regulating pancreatic cancer cells’ growth in vitro and tumor development in vivo. Methods: QTR-PCR was used to examine the expression of miR-137 in pancreatic cancer cell lines and tumor cells from human patients. Lentivirual vector containing miR-137 mimic was used to overexpress miR-137 in PANC-1 and MIA PaCa-2 cells. The effects of overexpressing miR-137 on pancreatic cancer cell invasion and chemo-sensitivity to 5-fluorouracil (5-FU) were examined by cell migration and survival essays in vitro. The molecular target of miR-137, pleiotropic growth factor (PTN), was down-regulated by siRNA to examine its effects on cancer cell invasion. MIA PaCa-2 cells with endogenously overexpressed miR-137 were transplanted into null mice to examine tumor growth in vivo. Results: We found miR-137 was markedly underexpressed in both pancreatic cancer cell lines and tumor cells from patients. In cancer cells, transfection of lentivirus containing miR-137 mimic was able to markedly upregulate endogenous expression of miR-137, inhibited cancer cell invasion and increased sensitivities to chemotherapy reagent 5-FU. PTN was significantly down-regulated by overexpressing miR-137 in pancreatic cancer cells, and knocking down PTN was effective to rescue the reduced cancer cell invasion ability caused by miR-137 overexpression. More importantly, overexpressing miR-137 led to significant inhibition on tumor formation, including reductions in tumor weight and tumor size in vivo. Conclusion: Our study demonstrated that miR-137 played an important role in pancreatic cancer development. It may become a new therapeutic target for gene therapy in patients suffered from pancreatic cancer.     

Estrogen receptor-associated expression of keratinocyte growth factor and its possible role in the inhibition of apoptosis in human breast cancer

Although estrogen is known to play a crucial role in the pathogenesis of breast cancer, the molecular mechanisms underlying the action of estrogen remain elusive. In the present study, we focused on keratinocyte growth factor (KGF) and its receptor (KGFR) in the pathogenesis of breast cancer, as a growth factor mediating estrogen action, since significant roles of KGF were demonstrated in various steroid hormone-dependent tissues. First, using paraffin-embedded specimens from 42 breast cancer patients, we examined expression patterns of KGF and KGFR by both immunohistochemistry using newly generated antibodies and nonradioactive in situ hybridization with T-T dimerized synthetic oligonucleotide probes. We next compared the results with the expression of estrogen receptor (ER) alpha and beta, proliferative activity and apoptotic frequency (TUNEL staining). Also, the similar approaches were taken to analyze the expression and role of KGF in ER-positive (MCF7, ZR-75-1) and ER-negative (SK-BR-3, MDA-MB-231) human breast cancer cell lines in vitro. In the surgical specimens, KGF was expressed in cancer cells as well as stromal cells in 19/42 cases (45%), while KGFR was found in cancer cells in 24/42 cases (57%). The distribution of protein and mRNA in the analysis of both KGF and KGFR expression generally coincided. Moreover, KGF expression was closely associated with the expression of ER alpha, and the coexpression of KGF and KGFR significantly correlated with lower TUNEL index, but not with proliferative activity. In accordance with the in vivo findings, KGF expression was detected only in ER alpha-positive MCF7 and ZR-75-1 cells in vitro. And more importantly, we found the inhibitory effect of KGF upon the induction of apoptosis by anticancer drugs in MCF7 cells. Collectively, our results indicate that ER alpha may be involved in KGF expression, and that KGF may play antiapoptotic roles, rather than mitogenic, in human breast cancer.     

Possible involvement of keratinocyte growth factor and its receptor in enhanced epithelial-cell proliferation and acquired recurrence of middle-ear cholesteatoma

Middle-ear cholesteatoma is characterized by enhanced proliferation of epithelial cells and granular tissue formation. However, the molecular mechanism underlying these pathological changes is largely unknown. Keratinocyte growth factor (KGF) is a mesenchymal cell-derived paracrine growth factor that specifically stimulates epithelial cell proliferation. In the present study, we investigated the possible involvement of KGF and its receptor, KGFR, in the pathogenesis of cholesteatoma using in situ hybridization and immunohistochemistry, respectively. We examined 56 cholesteatoma specimens, and 8 normal skin areas as control. KGF and KGFR expression was examined by immunohistochemistry using rabbit anti-human KGF and anti-human KGFR polyclonal antisera raised in our laboratories against synthetic peptides corresponding to parts of human KGF and KGFR, respectively. KGF protein and mRNA were detected exclusively in stromal fibroblasts and infiltrating T lymphocytes in 80% of cholesteatoma cases, whereas KGFR protein and mRNA were localized in the epithelium in 72% of cases. Assessment of the proliferative activity of cholesteatoma using the labeling index for Ki-67 showed a significantly higher Ki-67 labeling index (66%) in KGF+/KGFR+ cases than other cases. There was a significant correlation between KGF+/KGFR+ expression and recurrence. Our results indicate the possible involvement of both KGF and KGFR in enhanced epithelial cell proliferative activity and recurrence of cholesteatoma.     

Yes-associated protein (YAP65) in relation to Smad7 expression in human pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is characterized by multiple alterations in the TGF-beta signaling pathway. Yes-associated protein (YAP65) interacts with Smad7 thereby influencing TGF-beta signaling. In the present study, the expression of YAP65 in PDAC was analyzed in order to elucidate the potential role of this molecule in the pathogenesis of pancreatic cancer. YAP65 mRNA expression levels in human pancreatic tissue samples and cell lines were analyzed by Northern blotting and quantitative RT-PCR. Immunohistochemistry was carried out to localize and quantify YAP65 expression in relation to Smad7 expression and Smad4 mutations. The effects of TGF-beta1 on Smad7 and YAP65 mRNA expression were analyzed by quantitative RT-PCR. Enhanced expression of YAP65 mRNA was identified by Northern blotting and quantitative RT-PCR in PDAC in comparison to the normal pancreas (2.5-fold increase) and to chronic pancreatitis (1.3-fold increase). In the normal pancreas, YAP65 was absent in acinar cells, large ducts and islet cells, but exhibited moderate to strong immunoreactivity in centroacinar cells and ductules. Tubular complexes in CP and CP-like lesions in PDAC also exhibited strong staining. In contrast, weak to moderate YAP65 immunoreactivity was present in the cancer cells. There was no correlation between YAP65 immunostaining and Smad7 staining or Smad4 mutations in the cancer samples. TGF-beta1 strongly induced Smad7 mRNA in Colo-357 and in Panc-1 cells, but only slightly induced YAP65 mRNA in Colo-357 cells. In conclusion, YAP65 is expressed mainly in centroacinar and small ductal cells in the normal pancreas. In PDAC, YAP65 is present in tubular complexes and to a lesser extent in cancer cells. Together with the known function of YAP65 in different growth and differentiation regulating pathways, it is suggested that this gene plays a role in the normal and diseased pancreas.     

Metastatic Progression of Pancreatic Cancer: Changes in Antioxidant Enzymes and Cell Growth

Pancreatic cancer has a dismal prognosis due to the fact that patients present late when metastatic disease is already present. Previous studies have demonstrated that pancreatic cancer cells have decreased levels of MnSOD, which correlates well with increased rates of tumor cell proliferation. Recently, we have found that nude mice injected with MIA PaCa-2 human pancreatic cancer cells in the flank occasionally develop ascites and intra-abdominal metastatic deposits. Mice that developed ascites were sacrificed and the ascites cultured. Necropsy demonstrated metastatic tumors in the retroperitoneum, which were excised, digested, and cultured. Western blots, enzyme activity and enzyme activity gels were performed for manganese superoxide dismutase (MnSOD), copper/zinc (CuZnSOD), catalase, and glutathione peroxidase (GPx) in the ascites cell line, metastatic tumor cell line, MIA PaCa-2 primary pancreatic cancer cell line, and the Capan-1, a metastatic pancreatic cancer cell line. Cell growth, plating efficiency, growth in soft agar and growth in nude mice were determined in the ascites, metastatic tumor, and MIA PaCa-2 cell lines. MnSOD, CuZnSOD, and GPx protein and activity were increased in the ascites, metastatic tumor, and Capan-1 cell lines compared to MIA PaCa-2. The ascites and metastatic tumor cell lines had decreased cell growth, plating efficiency, and growth in soft agar, but the ascites cell line had increased cell growth in 4 and 1% O₂ concentrations in vitro and more rapid growth in vivo. Metastatic disease is associated with changes in the content and activity of antioxidant enzymes with an associated change in growth characteristics depending on the O₂ concentrations.     

Efficacy of gemcitabine conjugated and miRNA-205 complexed micelles for treatment of advanced pancreatic cancer

Clinical effectiveness of gemcitabine in pancreatic cancer is hindered due to its rapid plasma metabolism and development of chemo-resistance. We have previously delineated the significant role of miRNAs in mediating the growth and proliferation of cancer stem cells (CSCs) which in turn result in chemo-resistance, invasion and metastasis. Here, we designed self-assembling, gemcitabine conjugated cationic copolymers for co-delivery of a tumor suppressor miRNA-205 (miR-205) and evaluated their in vivo efficacy in a pancreatic cancer ectopic tumor model developed using gemcitabine resistant MIA PaCa-2^R cells. Combination formulations showed mean a particle size of <100 nm and gemcitabine payload of >10% w/w, exhibited miRNA complexation at N/P ratio of 4/1, sustained release of gemcitabine for >10 days, transfection efficiency of >90%, extended miRNA and drug stability in serum. Functional assays in gemcitabine resistant MIA PaCa-2^R and CAPAN-1^R pancreatic cancer cells revealed that the combination formulations effectively reversed chemo-resistance, invasion and migration. In pancreatic tumor model, the combination formulation treated group showed significant inhibition of tumor growth. Immuno-hiostochemical analysis revealed decreased tumor cell proliferation with increased apoptosis in the animals treated with miR-205 and gemcitabine combination.     

Keratinocyte growth factor-induced motility of breast cancer cells

Endogenous growth factors and cytokines are known to have a major influence on the progression, motility and invasiveness of tumor cells. We have reported previously that conditioned media from mouse fibroblasts increases the motility of breast cancer cells. Further, we determined that keratinocyte growth factor (KGF) was an active factor from mouse fibroblasts responsible for most of the motility response in breast cancer cells. The present study examined the effect of human KGF on the motility of estrogen receptor (ER)-positive and ER-negative human breast cancer cell lines in culture using time-lapse videomicroscopy to quantify cell motility. In the present study we observed that recombinant human KGF enhanced several parameters of cellular motility in ER-positive cells but not in ER-negative cell lines. Further, we observed that the level of KGF receptor (KGFR) expression in ER-positive cells was much greater than in the ER-negative cell lines. The motility response to KGF was found to be both dose-and time-dependent. Of the three ER-positive breast cancer cell lines tested, MCF-7 cells were the most responsive to KGF stimulation. Finally, MCF-7 cells grown in estrogen-depleted media did not respond to KGF. These results suggest that KGF from stromal tissue surrounding a primary tumor mass can enhance tumor cell motility and may be an early signal in the progression of breast cancer cells to a more motile and metastatic phenotype. Thus, KGF, KGFR and/or the KGF signaling pathway may be important therapeutic targets for the treatment or prevention of breast cancer metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.     

Enhanced expression of fibroblast growth factor receptor 2 IIIc promotes human pancreatic cancer cell proliferation

In pancreatic ductal adenocarcinoma (PDAC), the fibroblast growth factor receptor 1 (FGFR-1) IIIb isoform correlates with the inhibition of cancer cell proliferation, migration, and invasion, whereas FGFR-1 IIIc enhances cancer cell proliferation. The FGFR-2 IIIb isoform is expressed in PDAC, and its expression correlates with increased venous invasion. We examined the role of FGFR-2 IIIc in PDAC. FGFR-2 IIIc was expressed in all six pancreatic cancer cell lines examined and was highest in PANC-1 cells. FGFR-2 IIIc was abundant in the cancer cells from 83 of 117 PDAC cases, which correlated with decreased duration to development of liver metastasis after surgery. FGFR-2 IIIc-transfected cells exhibited increased proliferation in vitro and formed larger subcutaneous and orthotopic tumors, the latter producing more liver metastases. Moreover, FGF-2 exerted a more rapid stimulatory effect on the levels of phosphorylated extracellular signal-regulated kinase (p-ERK) in FGFR-2 IIIc stably transfected PANC-1 cells, compared with control cells. FGFR-2 IIIc-transfected cells also formed more spheres and contained more side population cells. Suppression of FGFR-2 IIIc expression inhibited the proliferation of PANC-1 cells, whereas an anti-FGFR-2 IIIc antibody inhibited the proliferation and migration of PANC-1 cells. Thus, high FGFR-2 IIIc levels in PDAC contribute to disease aggressiveness and confer to pancreatic cancer cells features suggestive of cancer stem cells, indicating that FGFR-2 IIIc may be a novel and important therapeutic target in PDAC.     

Keratinocyte Growth Factor Gene Electroporation into Skeletal Muscle as a Novel Gene Therapeutic Approach for Elastase-Induced Pulmonary Emphysema in Mice

Pulmonary emphysema is a progressive disease with airspace destruction and an effective therapy is needed. Keratinocyte growth factor (KGF) promotes pulmonary epithelial proliferation and has the potential to induce lung regeneration. The aim of this study was to determine the possibility of using KGF gene therapy for treatment of a mouse emphysema model induced by porcine pancreatic elastase (PPE). Eight-week-old BALB/c male mice treated with intra-tracheal PPE administration were transfected with 80 μg of a recombinant human KGF (rhKGF)-expressing FLAG-CMV14 plasmid (pKGF-FLAG gene), or with the pFLAG gene expressing plasmid as a control, into the quadriceps muscle by electroporation. In the lung, the expression of proliferating cell nuclear antigen (PCNA) was augmented, and surfactant protein A (SP-A) and KGF receptor (KGFR) were co-expressed in PCNA-positive cells. Moreover, endogenous KGF and KGFR gene expression increased significantly by pKGF-FLAG gene transfection. Arterial blood gas analysis revealed that the PaO₂ level was not significantly reduced on day 14 after PPE instillation with pKGF-FLAG gene transfection compared to that of normal mice. These results indicated that KGF gene therapy with electroporation stimulated lung epithelial proliferation and protected depression of pulmonary function in a mouse emphysema model, suggesting a possible method of treating pulmonary emphysema.     

Both inhibition and enhanced expression of miR-31 lead to reduced migration and invasion of pancreatic cancer cells

MicroRNAs (miRNAs) are short single-stranded RNA molecules that have a critical role in the regulation of gene expression. Alterations in miRNA expression levels have been observed in multiple tumor types and there is clear evidence on their active involvement in cancer development. Here, a comprehensive miRNA expression profiling in 16 pancreatic cancer cell lines and four normal pancreatic samples provided a specific molecular signature for pancreatic cancer and enabled us to identify 72 differentially expressed miRNAs with approximately half of them being up- and half downregulated in cancer cells as compared with normal samples. Of these, miR-31 was selected for further functional analyses based on its interesting "on-off" type expression profile, i.e., very low or even absent expression in normal pancreas and in six of the pancreatic cancer samples but extremely high expression in the remaining 10 cell lines. Quite unexpectedly, both the inhibition of miR-31 in AsPC-1 and HPAF-II pancreatic cancer cells with high endogenous expression and forced expression of miR-31 in MIA PaCa-2 with low endogenous levels led to reduced cell proliferation, migration, and invasion. More importantly, in AsPC-1 cells further enhancement of miR-31 also resulted in reduced cell migration and invasion, implicating that the level of miR-31 is critical for these phenotypes. This study highlights a specific miRNA expression pattern in pancreatic cancer and reveals that manipulation of miR-31 expression leads to reduced cell migration and invasion in pancreatic cancer.     

Expression of the thrombin receptor PAR-1 correlates with tumour cell differentiation of pancreatic adenocarcinoma in vitro

Patients with pancreatic cancer frequently suffer from thrombosis due to excess thrombin generation. Yet, the effects of thrombin on pancreatic cancer are still poorly understood. The thrombin receptor PAR-1 is responsible for cellular effects of thrombin. PAR-1 plays an important role in the progression of different solid tumours in vitro. In breast cancer the level of PAR-1 expression correlates with invasiveness. Our aim was to correlate PAR-1 mRNA and protein expression level with the grade of differentiation of pancreatic tissue and cancer cell lines. PAR-1 protein was not detectable in the epithelium of healthy pancreas. Analysis of PAR-1 protein expression by immunofluorescence staining of pancreatic cancer cell lines revealed a correlation to the grade of differentiation. Quantitative analysis of PAR-1 protein expression by Western Blot analysis confirmed these observations. Analysis of PAR-1 mRNA expression showed low levels in healthy pancreas compared to pancreatic cancer tissue and the pancreatic cancer cell line MIA PaCa-2. The level of PAR-1 mRNA differed up to 25 fold between the respective pancreatic cancer cell lines. The eminent differences in PAR-1 expression, both protein and mRNA, between healthy pancreatic tissue and pancreatic cancer in vivo and in vitro emphasise the putative role of PAR-1 in pancreatic cancer progression. This revised version was published online in July 2006 with corrections to the Cover Date.     

The RNA m6A methyltransferase METTL3 promotes pancreatic cancer cell proliferation and invasion

Epigenetic modifications are involved in carcinogenesis and METTL3 is involved in RNA methylation. This study aimed to explore the role of the RNA m6A methyltransferase METTL3 in pancreatic cancer cells. The m6A modification was analyzed in human pancreatic cancer and paracancerous specimens, as well as in the normal HPDE6-C7 pancreatic cell line and the MIA-PaCa-2 and BxPC-3 pancreatic cancer cell lines. Immunohistochemistry (IHC), western blotting, and RT-qPCR were used to detect the expression of METTL3. Cell lines were transfected with siRNAs against METLL3. Proliferation, invasion, and migration were examined. The functions of METTL3 were predicted by bioinformatics analysis. In the 40 patients included, high METTL3 expression was associated with high pathological stage (P = 0.02) and high N stage (P = 0.02). Survival was better in patients with low METTL3 expression compared with those with high MTTL3 expression (P < 0.01). METTL3 and CIITA expression levels were inversely correlated (r = ?0.71, P < 0.01). RNA m6A content in tumor specimens was significantly higher than that in paracancerous specimens. METTL3 protein and mRNA levels were significantly higher in tumor specimens compared with paracancerous specimens, as well as in cancerous cell lines vs. normal cells. METTL3 knockdown in MIA PaCa-2 and BxPC-3 cells decreased RNA m6A modifications. Cell proliferation, invasion, and migration were decreased by METTL3 knockdown in cancerous cell lines. A total of 673 differentially expressed genes were identified by bioinformatics: 659 were upregulated and 14 were downregulated. In conclusion, METTL3 is probably involved in pancreatic carcinogenesis. It could eventually be a prognostic marker or a treatment target.     

Genome-wide in vivo RNAi screen identifies ITIH5 as a metastasis suppressor in pancreatic cancer

The overwhelming majority of pancreatic ductal adenocarcinoma (PDAC) is not diagnosed until the cancer has metastasized, leading to an abysmal average life expectancy (3–6 months post-diagnosis). Earlier detection and more effective treatments have been hampered by inadequate understanding of the underlying molecular mechanisms controlling metastasis. We hypothesized that metastasis suppressors are involved in controlling metastasis in pancreatic cancer. Using an unbiased genome-wide shRNA screen, an shRNA library was transduced into the non-metastatic PDAC line S2-028 followed by intrasplenic injection. Resulting liver metastases were individually isolated from these mice. One liver metastatic nodule contained shRNA for ITIH5 (Inter-alpha-trypsin inhibitor heavy chain 5), suggesting that ITIH5 may act as a metastasis suppressor. Consistent with this notion, metastatic PDAC cell lines had significantly lower protein expression of ITIH5 compared to immortalized pancreatic ductal epithelial cells and non-/poorly-metastatic PDAC cell lines. By manipulating expression of ITIH5 in different PDAC cell lines (over-expression in metastatic, knockdown in non-metastatic) functional and selective regulation of metastasis was observed for ITIH5. Orthotopic tumor growth of PDAC cells was not blocked following orthotopic injection. In vitro ITIH5 over-expression inhibited motility and invasion. Immunohistochemical analysis of a human PDAC tissue microarray revealed that ITIH5 expression inversely correlated with both survival and invasion/metastasis. ITIH5 is, therefore, functionally validated as a PDAC metastasis suppressor and shows promise as a prognostic biomarker.     

Expression of keratinocyte growth factor/fibroblast growth factor-7 and its receptor in human lung cancer: correlation with tumour proliferative activity and patient prognosis

Keratinocyte growth factor (KGF)/fibroblast growth factor-7 (FGF-7), a mesenchymal cell-derived paracrine growth factor that specifically stimulates epithelial cell proliferation, has been implicated in the repair of lung tissue. The present study was designed to determine the expression and role of KGF and its receptor (KGFR) in human lung cancer tissues, particularly in relation to cancer cell kinetics and prognosis. Thirty-one adenocarcinomas and 30 squamous cell carcinomas, and ten normal lung tissues as a control, were examined. The expression of KGF and KGFR proteins was examined using rabbit polyclonal anti-human KGF and anti-human KGFR antisera raised in the authors' laboratories against synthetic peptides corresponding to parts of human KGF KGFR, respectively. Their specificity was confirmed in lung tumour tissues by western blotting various controls. Proliferative activity was assessed by determining the labelling index (LI) for Ki-67 antigen. Immunohistochemistry revealed that tissue co-expression of KGF KGFR correlated significantly with higher differentiation grades in squamous cell carcinoma. Conversely, in adenocarcinoma, co-expression correlated with lower differentiation grades high Ki-67 LI, was significantly associated with lymph node metastasis shorter 5-year survival. Therefore, the results indicate that co-expression of KGF KGFR correlates significantly with poor prognosis in adenocarcinoma, but not in squamous cell carcinoma, of the lung.     

维甲酸对高氧暴露新生大鼠肺组织角化细胞生长因子及其受体表达的影响

目的: 探讨高氧暴露新生大鼠肺组织结构的变化和角化细胞生长因子(KGF)及其受体(KGFR)的表达情况及维甲酸(RA)对其的影响。方法: 将出生24 h内SD大鼠90只随机分为3组,Ⅰ组:空气+生理盐水(NS);Ⅱ组:高氧+NS;Ⅲ组:高氧+RA。Ⅱ、Ⅲ组持续暴露于85% O₂中,Ⅰ组置于空气中;Ⅲ组每天腹腔注射RA,Ⅰ、Ⅱ组每天腹腔注射NS。分别于生后3、7、14 d取肺标本,用HE染色法观察肺组织结构变化及辐射状肺泡计数(RAC);RT-PCR检测KGF和KGFR mRNA表达强度和免疫组织化学法检测KGF蛋白表达水平。结果: (1)生后第14 d,Ⅱ、Ⅲ组较Ⅰ组RAC值显著减少(P<0.05),但Ⅲ组较Ⅱ组明显增高(P<0.05)。(2)与Ⅰ组相比,Ⅱ组3 d时,KGF mRNA表达明显增强(P<0.05);其后开始下降,7 d仍高于Ⅰ组(P<0.05);14 d时较Ⅰ组有所降低(P<0.05);Ⅲ组各时点表达量均高于同期Ⅱ组(P<0.05)。3 d时,各组KGFR mRNA表达量无明显差异;7 d、14 d时,Ⅱ、Ⅲ组表达量明显低于Ⅰ组(均P<0.05),且Ⅱ组和Ⅲ组之间无显著差异(P>0.05)。(3)KGF阳性细胞主要分布在部分肺泡壁及肺泡周围血管内皮细胞和间质细胞。KGF蛋白表达强度与其mRNA表达变化相似。结论: RA可促进肺组织KGF表达,改善高氧所致肺发育受阻。对未成熟肺高氧损伤有一定的保护作用。