巴佛洛霉素A1抑制胃癌SGC-7901细胞中VEGF-C的表达

目的:研究巴佛洛霉素A1(Bafilomycin A1)对胃癌细胞株SGC-7901的增殖、迁移和血管生成的影响,并探讨可能的机制.方法:巴佛洛霉素A1(10 nmol/mL)处理SGC-7901细胞后,检测液泡-ATP酶(vacular-ATPases,V-ATPases)活性及培养液pH值,并分别用CCK-8法检测...     

Calcium carbonate nanoparticle delivering vascular endothelial growth factor-C siRNA effectively inhibits lymphangiogenesis and growth of gastric cancer in vivo

A nonviral gene carrier, calcium carbonate (CaCO3) nanoparticle, was evaluated for efficient in vitro and in vivo delivery of small interfering RNA (siRNA) targeting vascular endothelial growth factor-C (VEGF-C). The chemically synthesized CaCO3 nanoparticle has a 58 nm diameter and +28.6 mV positive surface charge. It is capable of forming a CaCO3 nanoparticle-DNA complex and transferring DNA into targeted cells with high transfection efficiency while effectively protecting the encapsulated DNA from degradation. Furthermore, the CaCO3 nanoparticle-DNA complex has no obvious cytotoxicity for SGC-7901 cells, while a liposome-DNA complex exhibited measurable cytotoxicity. SGC-7901 cells transfected with a VEGF-C-targeted siRNA via CaCO3 nanoparticle exhibit significantly reduced VEGF-C expression as measured by real-time PCR and enzyme-linked immunosorbent assay; whereas no decrease in VEGF-C expression is observed in cells treated by control transfection. Transfection of SGC-7901 cells with VEGF-C siRNA via CaCO3 nanoparticle also dramatically suppresses tumor lymphangiogenesis, tumor growth and regional lymph-node metastasis in subcutaneous xenografts. Significant downregulation of VEGF-C messenger RNA expression in a subcutaneous xenograft derived from VEGF-C siRNA-treated SGC-7901 cells was confirmed by real-time PCR as compared to controls. We conclude that CaCO3 nanoparticle is a novel and nonviral system for effective delivery of siRNA for cancer gene therapy.     

Decreased expression of CCNG2 is significantly linked to the malignant transformation of gastric carcinoma

This study aimed to analyze the expression, clinical significance of cyclin G2 (CCNG2) in gastric carcinoma, and the biological effect in its cell line by CCNG2 overexpression. Immunohistochemistry and western blot were used to analyze CCNG2 protein expression in 87 cases of gastric cancer and normal tissues to study on the relationship between CCNG2 expression and clinical factors. CCNG2 lentiviral vector was transfected into gastric SGC-7901 cell line. RT-PCR and western blot were used to detect the mRNA level and protein of CCNG2. MTT assay and cell cycle were also conducted as to the influence of the upregulated expression of CCNG2 that might be found on SGC-7901 cell biological effect. Immunohistochemically, the level of CCNG2 protein expression was found to be significantly lower in gastric cancer tissue than in normal tissues (P?<?0.05). Western blot shows that the relative amount of CCNG2 protein in gastric cancer tissue was found to be significantly lower than in normal tissues (P?<?0.05). The level of CCNG2 protein expression was correlated with T stages, lymph node metastasis, clinical stage, and histological grade (P?<?0.05). Loss of CCNG2 expression correlated significantly with poor overall survival time by Kaplan–Meier analysis (P?<?0.05). The result of biological function showed that SGC-7901 cell-transfected CCNG2 had a lower survival fraction, higher percentage of the G0/G1 phases, and lower CDK2 protein expression compared with SGC-7901 cell untransfected CCNG2 (P?<?0.05). CCNG2 expression decreased in gastric cancer and correlated significantly T stages, lymph node metastasis, clinical stage, histological grade, and poor overall survival, suggesting that CCNG2 may play important roles as a negative regulator to gastric cancer cell by promoting degradation of CDK2.     

蒿甲醚对胃癌细胞增殖、侵袭和迁移的抑制作用研究

目的:研究蒿甲醚对胃癌细胞（AGS和SGC-7901）的增殖、侵袭以及迁移的影响并探讨其分子机制。方法:分别利用MTT、集落形成试验检测胃癌细胞的活力和生长;流式细胞技术检测胃癌细胞的凋亡率;利用细胞侵袭和划痕愈合试验检测胃癌细胞的侵袭和迁移;Western blot检测相关蛋白的表达水平。结果:蒿甲醚（0~800 μmol/L）能够浓度和时间依赖性的抑制 AGS和SGC-7901细胞的增殖（P＜0.05）。集落形成试验以及流式细胞术结果显示蒿甲醚（400 和 600 μmol/L）能够抑制AGS和SGC-7901细胞的生长以及促进细胞凋亡（P＜0.05）。细胞侵袭和划痕愈合试验发现蒿甲醚（400 和 600 μmol/L）能够抑制AGS和SGC-7901细胞的侵袭和迁移（P＜0.05）。Western blot结果显示蒿甲醚(400 和 600 μmol/L)能够增加AGS和SGC-7901细胞的cleaved caspase-3,cleaved caspase-9以及Bax的蛋白水平（P＜0.05）;同时能够抑制N-cadherin 和vimentin的蛋白表达并促进E-cadherin蛋白的表达。结论:蒿甲醚可以显著抑制胃癌细胞的增殖、侵袭以及迁移,其机制可能是与促进细胞凋亡以及抑制上皮间质转化有关。     

MIA-dependent angiogenesis and lymphangiogenesis are closely associated with progression,nodal metastasis and poor prognosis in tongue squamous cell carcinoma

We examined the role of angiogenesis/lymphangiogenesis and the relationship between melanoma inhibitory activity (MIA) and angiogenesis or lymphangiogenesis in oral squamous cell carcinoma (OSCC). One hundred and one formalin-fixed, paraffin-embedded specimens of primary OSCC were evaluated for microvessel density (MVD), lymphovessel density (LVD), expression of vascular endothelial growth factor (VEGF), VEGF-C, VEGF-D and MIA. Fresh frozen 18 samples of primary OSCC were further examined for the expression of VEGF, VEGF-C, VEGF-D and MIA protein by enzyme-linked immunosorbent assay (ELISA). In in vitro analysis, we studied the change of VEGF, VEGF-C and VEGF-D expression after MIA siRNA treatment. Higher MVD, LVD and VEGF expression levels were closely associated with tumour progression, nodal metastasis and poor prognosis. Expression levels of VEGF-C and VEGF-D were only related with nodal metastasis. MIA expression was significantly associated with MVD, LVD, VEGF, VEGF-C and VEGF-D expression by immunohistochemistry and ELISA assay. VEGF, VEGF-C, VEGF-D and MIA expression levels of metastatic tongue cancer HSC-3 cells were higher than those with no metastatic HSC-4 cells, and VEGF, VEGF-C and VEGF-D expression levels were decreased by MIA siRNA treatment in both cells. MIA-dependent angiogenesis/lymphangiogenesis might be a useful therapeutic target in progressive and metastatic OSCC.     

Expressions of COX-2 and VEGF-C in gastric cancer: correlations with lymphangiogenesis and prognostic implications

Background

Cyclooxygenase-2 (COX-2) has recently been considered to promote lymphangiogenesis by up-regulating vascular endothelial growth factor-C (VEGF-C) in breast and lung cancer. However, the impact of COX-2 on lymphangiogenesis of gastric cancer remains unclear. This study aims to test the expression of COX-2 and VEGF-C in human gastric cancer, and to analyze the correlation with lymphatic vessel density (LVD), clinicopathologic features and survival prognosis.

Methods

Using immunohistochemistry, COX-2, VEGF-C and level of LVD were analyzed in 56 R0-resected primary gastric adenocarcinomas, while paracancerous normal mucosal tissues were also collected as control from 25 concurrent patients. The relationships among COX-2 and VEGF-C expression, LVD, and clinicopathologic parameters were analyzed. The correlations of COX-2, VEGF-C and level of LVD with patient prognosis were also evaluated by univariate tests and multivariate Cox regression.

Results

The expression rates of COX-2 and VEGF-C were 69.64% and 55.36%, respectively, in gastric carcinoma. Peritumoral LVD was significantly higher than that in both normal and intratumoral tissue (P < 0.05). It was significantly correlated with lymph node metastasis and invasion depth (P = 0.003, P = 0.05). VEGF-C was significantly associated with peritumoral LVD (r = 0.308, P = 0.021). However, COX-2 was not correlated with VEGF-C (r = 0.110, P = 0.419) or LVD (r = 0.042, P = 0.758). Univariate analysis showed that survival time was impaired by higher COX-2 expression and higher peritumoral LVD. Multivariate survival analysis showed that age, COX-2 expression and peritumoral LVD were independent prognostic factors.

Conclusions

Although COX-2 expression was associated with survival time, it was not correlated with VEGF-C and peritumoral LVD. Our data did not show that overexpression of COX-2 promotes tumor lymphangiogenesis through an up-regulation of VEGF-C expression in gastric carcinoma. Age, COX-2 and peritumoral LVD were independent prognostic factors for human gastric carcinoma.     

Overexpression of HOXA1 correlates with poor prognosis in patients with hepatocellular carcinoma

HOXA1 overexpression is sufficient for malignant transformation of nontumorigenic epithelial cells. It is known that HOXA1, which was upregulated in squamous cell carcinomas, affects both cell growth and death. The forced expression of HOXA1 in human breast cancer cells results in increased cell growth activity. However, it has not been reported in hepatocellular carcinoma (HCC). In this study, we used immunohistochemistry to compare HOXA1 protein expression in HCC and normal liver tissues and further analyzed HOXA1 protein expression in 156 clinicopathologically characterized HCC cases. We stably knocked down the endogenous expression level of HOXA1 in HepG2 cells with specific shRNA-expressing lentiviral vector. Following the successful establishment of stable cells, we examined in vitro cell growth by the MTT assay, anchorage-independent growth through a soft agar colony formation assay and cell migration/invasion by transwell and Boyden chamber assay. In addition, we also investigated in vivo tumor growth by xenograft transplantation of HepG2 cells into nude mice. Our results showed that the protein expression level of HOXA1 was markedly higher in HCC tissues than that in normal liver tissue (P?=?0.019). In addition, a high expression level of HOXA1 protein was positively correlated with the T classification (P?<?0.001), the N classification (P?<?0.001), distant metastasis (P?=?0.004), and the clinical stage (P?<?0.001) of HCC patients. Patients with higher HOXA1 expression showed a significantly shorter overall survival time compared with patients with low HOXA1 expression. Multivariate analysis suggested that HOXA1 expression might be an independent prognostic indicator (P?<?0.001) for the survival of patients with HCC. HOXA1-specific shRNA (shHOXA1) successfully knocked down HOXA1 endogenous expression in HepG2 cells. Compared to the parental and control shRNA-transfected (shCtrl) HepG2 cells, the shHOXA1 cells exhibited significantly reduced in vitro cell growth, anchorage-independent growth, and cell migration and invasion (P?<?0.05). In vivo, the xenograft transplants from shHOXA1 cells gave rise to much smaller tumors compared with those from shCtrl cells. Collectively, high HOXA1 expression is associated with poor overall survival in patients with HCC. The downregulation of HOXA1 inhibits growth, anchorage-independent growth, and migration and invasion of HepG2 cells.     

siRNA抑制胃腺癌VEGF-C表达和淋巴管生成

目的 研究瘤内注射VEGF-C siRNA抑制胃癌移植瘤VEGF-C表达和肿瘤淋巴管生成的有效性.方法 建立裸鼠胃癌皮下移植瘤模型随机分为4组:VEGF-C sLRNA脂质体混合液组、单脂质体组、单siRNA组和PBS组,对肿瘤进行原位注射干预,记录各实验组肿瘤体积变化,免疫组织化学法检测各实验组肿瘤组织VEGF-C的表达,并通过抗人CD31和抗人LYVE-1单克隆抗体检测瘤体内血管和淋巴管生成情况.结果 免疫组化显示干扰组肿瘤细胞VEGF-C染色减弱,和对照组相比VEGF-C表达下调68.3%(P<0.01),而胃癌组织中淋巴管密度(LVD)值干预组和对照组分别为3.2±1.3、9.8±2.7,VEGF-C siRNA干预组LVD值下降至对照组的32.7%(P<0.01),而MVD值无明显差异(P>0.05).结论 瘤内注射VEGF-C siRNA能显著下调肿瘤组织内VEGF-C的表达,有效抑制肿瘤生长和瘤内淋巴管生成,而对肿瘤血管生成无影响.     

胃癌组织COX-2、VEGF-C表达与淋巴结转移及预后关系的研究

目的:探讨环氧化酶-2(cyclooxygenase-2,COX-2)、血管内皮生长因子C(VEGF-C)在胃癌组织中的表达及其与淋巴管生成、淋巴结转移及预后的关系.方法:采用免疫组织化学SABC法检测 51例胃癌及相应的癌旁组织COX-2、VEGF-C及受体VEGFR-3表达,计数肿瘤内淋巴管密度(LVD),并结合临床病理特征和随访资料进行分析.结果:胃癌组织COX-2、VEGF-C表达阳性率分别为62.8%(32/51),60.7%(31/51).COX-2表达与VEGF-C(r=O.74,P＜0.05)、临床分期(r=0.34,P＜0.05)、淋巴管密度(r=0.69,P＜0.01)和淋巴结转移(r=0.57,P＜0.01)呈正相关,与病理分化呈负相关(r=-0.58,P＜0.01).VEGF-C表达与淋巴管密度(r=0.45,P＜0.01)、淋巴结转移呈正相关(r=0.46,P＜0.05).随访5年,胃癌组织COX-2表达与生存率呈负相关,COX-2表达阴性组5年生存率(36.8%)显著高于COX-2表达阳性组(15.6%)(P＜0.05).结论:在胃癌组织中,COX-2、VEGF-C高表达,COX-2与VEGF-C、淋巴管密度、淋巴结转移呈正相关.推测COX-2通过诱导VEGF-C表达参与淋巴结转移.胃癌组织COX-2检测可能对推测预后具有重要意义.     

Tumor-associated mesothelial cells are negative prognostic factors in gastric cancer and promote peritoneal dissemination of adherent gastric cancer cells by chemotaxis

Peritoneal dissemination is highly frequent in gastric cancer. Damage to human peritoneal mesothelial cell (HPMC) barriers provokes gastric cancer peritoneal dissemination (GCPD), the key events during GCPD, is characterized by fibroblastic development. In this study, we have studied the association between fibroblast activation protein (FAP) expression in peritoneum and the pathological features of the primary tumor. The clinical prognosis of gastric cancer patients was evaluated according to FAP expression. In a gastric cancer cell-HPMC co-culture system, expression of E-cadherin, α-smooth muscle actin, and FAP were evaluated by Western blotting. Gastric cancer cell migration and adhesion to HPMC were also assayed. Our results showed positive peritoneal staining of FAP in 36/86 cases (41.9 %), which was associated with a higher TNM stage in primary gastric cancer and higher incidence of GCPD (both p?<?0.05). Survival analysis showed FAP expression was an independent prognostic factor of poor survival (p?=?0.02). Peritoneum of FAP-positive expression exhibited a distinct fibrotic development and expressed higher level of the mesenchymal marker α-SMA, which was confirmed by the in vitro Western blot assay. In HPMC and gastric cancer cell adherence assay, SGC-7901 cells preferentially adhered to TA-HPMC at different cell densities (both p?<?0.05). Additionally, SGC-7901 cells were more prone to chemotaxis by FAP-expressed tumor-associated–human peritoneal mesothelial cells (TA-HPMC) compared with HPMC co-cultured with normal gastric glandular epithelial cells in a time-dependent manner (both p?<?0.05). Our study indicated a positive correlation between peritoneum FAP expression and GCPD. FAP-expressed TA-HPMC might be an important cellular component and instigator of GCPD.     

miR-34a regulates cisplatin-induce gastric cancer cell death by modulating PI3K/AKT/survivin pathway

The purposes of this study were to determine the expression profiles of microRNA-34a (miR-34a) in human gastric cancer cell line (SGC-7901) and cisplatin-resistant cell lines (SGC-7901/DDP), and to establish the correlation between miR-34a expression profile and the sensitivity of human gastric cancer cell to cisplatin-based pattern, thereby providing new methods and strategies for treating gastric cancer. Gastric cancer cell line (SGC-7901) and cisplatin-resistant cell line (SGC-7901/DDP) were cultivated in vitro, respectively. Quantitative real-time PCR (qRT-PCR) and Western blot were utilized to determine the expression profiles of miR-34a and survivin in both gastric cancer cell lines. With miR-34a mimic and miR-34a inhibitor transfected into SGC-7901 and SGC-7901/DDP for 48 h, post-transfection changes of miR-34a expression was determined; the effects of miR-34a ectopic expression on the viability of cisplatin-induce gastric cancer cell were assayed by the MTT method. The effects of miR-34a ectopic expression on apoptosis of cisplatin-induce gastric cancer cell were determined by Annexin V/propidium iodide (PI) double staining method and flow cytometry. The effects of miR-34a ectopic expression on the AKT and p-AKT expression of cisplatin-induce gastric cancer cells were determined by Western blot and flow cytometry with the PI3K pathway inhibitor Wortmannin. As shown by qRT-PCR and Western blot analyses, the expression of miR-34a in cisplatin-resistant cell lines decreased significantly in comparison to that of SGC-7901 cell line (p?<?0.05), while significant up-regulation of survivin expression was also observed (p?<?0.05). Compared with the control group, the expression of miR-34a increased significantly in SGC-7901 cells transfected with miR-34a mimic for 48 h (p?<?0.01). After miR-34a inhibitor transfection, the expression of miR-34a decreased significantly (p?<?0.05). The viability of cisplatin-induce gastric cancer cells increased significantly (p?<?0.05) with significant decrease of apoptosis after miR-34a expression inhibition, as demonstrated by MTT and flow cytometry with miR-34a over-expression, the viability of cisplatin-induce gastric cancer cells decreased significantly (p?<?0.05), with significant apoptosis increase (p?<?0.05). As shown by Western blot and flow cytometry, in comparison to the control group, Wortmannin could inhibit miR-34a inhibitor and DDP induced up-regulation of p-AKT significantly (p?<?0.05) and stimulated apoptosis. In conclusion, miR-34a expression was down-regulated in cisplatin-resistant cell lines. miR-34a over-expression could improve the sensitivity of gastric cancer cells against cisplatin-based chemotherapies, with PI3K/AKT/survivin signaling pathway possibly involved in the mechanism.     

奥曲肽对胃癌细胞转录活化蛋白-1的抑制作用

背景与目的:生长抑素是一种多功能神经肽,其本身及其类似物能抑制多种内分泌肿瘤及某些胃肠肿瘤的生长,但是否能抑制胃癌的生长并不清楚。因此,本研究拟探讨生长抑素类似物奥曲肽对胃癌细胞生长的影响及其机制。方法:不同浓度的奥曲肽作用于人胃癌SGC-7901细胞24h后,用免疫印迹法检测奥曲肽对SGC-7901细胞中c-Fos、ERK蛋白表达的影响。建立人胃癌细胞裸鼠原位移植瘤模型,奥曲肽治疗8周,观察奥曲肽对胃癌生长的影响;免疫组化法检测裸鼠人胃癌组织c-Fos和ERK表达的变化。在此基础上,采用EMSA技术检测奥曲肽对胃癌细胞AP-1活化的影响。结果:1×10-5mol/L奥曲肽可明显降低胃癌细胞的3H-TdR的掺入;奥曲肽能抑制人胃癌细胞裸鼠原位移植瘤的生长,抑瘤率为62.3%。SGC-7901胃癌细胞经不同浓度奥曲肽作用后,其c-Fos和ERK的表达水平均有不同程度下降;组织标本检测亦有类似变化。EMSA分析显示,胃癌细胞有基础水平的AP-1活化,20%血清能刺激AP-1的结合力,奥曲肽能抑制这种刺激作用。结论:奥曲肽通过抑制胃癌c-Fos、ERK蛋白的表达而抑制AP-1的结合活性,从而抑制胃癌的生长。     

血管内皮生长因子C在胃癌中的表达及其与淋巴结转移的关系

目的 研究血管内皮生长因子C(VEGF-C)在胃癌中的表达并探讨其与淋巴结转移的关系。 方法应用逆转录-聚合酶链反应(RT-PCR)检测VEGF-Cm RNA在5株胃癌细胞株中的表达情况,同时采用免疫组化法,检测63 例接受根治性切除手术病例的胃癌组织标本VEGF-C蛋白表达。 结果 VEGF-C mRNA表达于胃癌细胞株MKN-45、SGC-7901及AGS。VEGF-C蛋白则在52．4％(33／63)的病例中呈阳性表达。在 伴淋巴结转移的胃癌中,VEGF-C表达较无淋巴结转移者更显著(P<0．01)。同时,VEGF-C表达与淋巴管浸润和TNM分期密切相 关(P<0．01),但与年龄、性别、肿瘤大小、位置、Lauren分型、浸润深度和血管浸润均无明显相关。 结论 VEGF-C的表达与胃癌淋巴结转移密切相关,同时,淋巴管生成可能成为治疗胃癌的一个新靶点。     

血管内皮生长因子-C干扰对人类结肠癌裸鼠移植瘤模型淋巴管生成的影响

 目的　构建携带有RNA干扰片段的腺病毒载体Ad5F35-VEGF-C siRNA-EGFP,探讨人类结肠癌BALB／c裸鼠皮下移植瘤模型瘤内注射腺病毒载体Ad5F35-VEGF-C siRNA-EGFP抑制血管内皮生长因子-C（VEGF-C）表达、结肠癌生长以及结肠癌淋巴管生成的效果。方法　选择针对人类VEGF-C mRNA的特异性siRNA靶序列,设计合成其相应的双链DNA,利用 BamHI、HindⅢ双酶切插入pDC316-EGFP-U6载体后构建穿梭质粒pDC316-VEGF-C siRNA-EGFP-U6,再与骨架质粒pBHGF35共转染293细胞,同源重组,酶切鉴定,包装扩增后得到重组腺病毒Ad5F35-VEGF-C siRNA-EGFP-U6。裸鼠皮下注射LoVo细胞构建人类结肠癌皮下移植瘤模型24只,随机分为4组（每组6只）：以腺病毒、空病毒、裸siRNA以及PBS分别进行瘤内原位注射干预,计算肿瘤体积变化并绘制生长曲线,使用抗LYVE-1单抗和抗CD34单抗分别染色瘤内的血管和淋巴管,检测瘤内淋巴管和血管生成情况,计算微血管密度（MVD）,微淋巴管密度（LVD）。结果　腺病毒组肿瘤体积明显小于其他各组,腺病毒组与PBS对照组LVD 分别为8.47±2.1,17.35±4.7（P＜0.05）,腺病毒组与PBS对照组MVD分别为22.65±6.04,23.19±7.63（P＞0.05）。结论　实验设计并合成的腺病毒载体介导的VEGF-C siRNA,在人类结肠癌裸鼠移植瘤模型中,瘤内注射腺病毒载体能显著抑制移植瘤的生长和肿瘤淋巴管生成,而对肿瘤血管生长无显著影响。     

血管内皮生长因子C在胃癌中的表达及其与淋巴结转移的关系

目的研究血管内皮生长因子 C(VEGF-C)在胃癌中的表达并探讨其与淋巴结转移的关系。方法应用逆转录-聚合酶链反应(RT-PCR)检测 VEGF-Cm RNA 在5株胃癌细胞株中的表达情况,同时采用免疫组化法,检测63例接受根治性切除手术病例的胃癌组织标本 VEGF-C 蛋白表达。结果 VEGF-C mRNA 表达于胃癌细胞株 MKN45、SGC-7901及 AGS。VEGF-C 蛋白则在52.4%(33/63)的病例中呈阳性表达。在伴淋巴结转移的胃癌中,VEGF-C 表达较无淋巴结转移者更显著(P<0.01)。同时,VEGF-C 表达与淋巴管浸润和 TNM 分期密切相关(P<0.01),但与年龄、性别、肿瘤大小、位置、Lauren 分型、浸润深度和血管浸润均无明显相关。结论 VEGF-C 的表达与胃癌淋巴结转移密切相关,同时,淋巴管生成可能成为治疗胃癌的一个新靶点。     

Different patterns of NF-κB and Notch1 signaling contribute to tumor-induced lymphangiogenesis of esophageal squamous cell carcinoma

Background

Lymph node involvement and tumor-induced lymphangiogenesis appear as the earliest features of esophageal squamous cell carcinoma (ESCC), although the molecular regulatory mechanisms involved have remained unclear. Our aim was to investigate the contribution of NF-κB and Notch1 signaling to lymph node involvement and tumor-induced lymphangiogenesis in ESCC.

Material and methods

NF-κB and Notch1 expression in 60 tissue samples of ESCC were assessed by immunohistochemical staining. The correlations of NF-κB and Notch1 with lymph node involvement, lymphatic vessel density (LVD), podoplanin, and vascular endothelial growth factor-C (VEGF-C) were further evaluated to determine the association of NF-κB and Notch1 expression with tumor-induced lymphangiogenesis.

Results

Chi-square tests revealed that NF-κB and Notch1 expression in ESCC tissues were significant associated with lymph node metastasis, LVD, podoplanin, and VEGF-C expression. Strong expression of NF-κB, but weak expression of Notch1, was observed in tumor tissues with lymph nodes involvement (P < 0.05 for both). The mean histoscores of LVD, podoplanin, and VEGF-C staining were higher in high-NF-κB-expressing tissue than in low-expressing tissue (P < 0.05 for each). In contrast, the mean histoscores of LVD and VEGF-C staining were lower in high-Notch1-expressing tissue than in low-expressing tissue (P < 0.05 for both). A multiple factors analysis of LVD and VEGF-C further demonstrated that LVD and VEGF-C status were significantly correlated with NF-κB and Notch1 expression in tumors. NF-κB and Notch1 expression were also significantly inversely correlated (P < 0.05).

Conclusion

These results suggest that different patterns of NF-κB and Notch1 signaling contribute to lymph nodes metastasis and tumor-induced lymphangiogenesis of ESCC, and reveal that up-regulation of NF-κB is associated with down-regulation of Notch1 in tumor tissue.     

沉默乙酰肝素酶基因对胃癌生物学行为的影响

目的 探讨乙酰肝素酶(HPA)沉默对人胃癌裸鼠移植瘤生长、转移和血管形成的影响.方法 利用人胃癌SGC-7901细胞和HPA被沉默的SGC-7901-HPA-细胞,分别建立6只裸鼠皮下移植瘤模型,观察成瘤的时间、肿瘤生长速度和体积.应用逆转录聚合酶链反应(RT-PCR)和Western blot方法分别检测皮下移植瘤组织中HPA mRNA和蛋白的表达,应用免疫组织化学SP法检测皮下移植瘤组织的微血管密度(MVD).将皮下移植瘤细胞分别注射入6只裸鼠腹腔,建立腹腔转移瘤,并观察成瘤情况.结果 SGC-7901细胞和SGC-7901-HPA-细胞在裸鼠皮下均能生长出移植瘤,分别在接种后第4天后和第7天后出现肉眼可见的肿瘤,接种SGC-7901-HPA-细胞的裸鼠移植瘤生长较慢,MVD为(11.35±1.94)个/高倍视野,明显低于接种SGC-7901细胞组[(20.69±1.20)个/高倍视野,P＜0.05].接种SGC-7901-HPA-细胞与接种SGC-7901细胞的裸鼠皮下移植瘤组织相比,HPA mRNA和蛋白的表达均降低.由SGC-7901细胞皮下移植瘤组织建立腹腔转移瘤的裸鼠,有3只成瘤,在肝脏、大网膜、肠系膜、右肾形成了4处转移灶,且体积较大.而接种SGC-7901-HPA-细胞皮下移植瘤组织的裸鼠,仅有1只在肝脏和右肾形成了转移灶,而且瘤体较小.结论 HPA沉默后抑制了人胃癌在裸鼠体内的生长、转移和血管形成,HPA有可能成为预防和治疗胃癌的一个新靶H点.