Angiogenesis,lymphangiogenesis, and tumor progression

Angiogenesis plays an important role for the growth and metastasis of malignant tumors. The "angiogenic switch" may even precede the development of other traits that contribute to the malignant phenotype. The switch to the angiogenic phenotype is thought to be induced by a change in the balance of positive and negative regulators of angiogenesis. The main emphasis of this review is to discuss the role of two potent endogenous inhibitors, thrombospondin-(TSP-)1 and TSP-2, for the development and progression of tumors. The recent identification of specific growth factors for lymphatic vessels and of new lymphatic-specific markers provided evidence for an active role of the lymphatic system during the metastasis process. Endogenous inhibitors of lymphangiogenesis have not yet been detected and until recently it was unclear whether or not the known endogenous angiogenesis inhibitors may also have some additional effects on lymphangiogenesis. The data provided indicate that angiogenesis inhibitors specifically inhibit tumor progression but fail to block the conversion of premalignant to malignant tumors. Moreover, angiogenesis inhibitors may have some elective effects on the formation of blood vessels but not on lymphatic vessels. These results will have implications for the further development and clinical use of angiogenesis inhibitors since they indicate that inhibitors might most efficiently be used to target early stages of tumor progression and in combination with specific inhibitors of lymphangiogenesis.     

宫颈癌VEGF-C表达和淋巴管、血管生成关系的探讨

目的:检测宫颈癌组织中血管内皮生长因子-C(VEGF-C)、受体VEGFR-3和CD34的表达,探讨VEGF-C与癌周淋巴管、血管生成和肿瘤转移的关系。方法:采用免疫组化法检测55例宫颈癌组织中VEGF-C、VEGFR-3和CD34的表达。结果:55例宫颈癌组织VEGF-C阳性率为69.1%(38/55),VEGFR-3阳性率为61.8%(34/55),二者表达高度一致(P<0.01)。淋巴结转移组中VEGF-C与VEGFR-3阳性表达明显高于无转移组(P<0.05)。低分化组VEGF-C和VEGFR-3的表达明显高于高、中分化组(P<0.05)。随着临床分期增加,VEGFR-3表达的阳性率增高(P<0.01)。淋巴结转移组中淋巴管密度(LMVD)明显高于无转移组(P<0.01)。VEGF-C表达阳性的组织中血管密度(MVD)明显升高(P<0.05)。VEGF-C和VEGFR-3表达阳性的患者生存率有降低的趋势。结论:宫颈癌中VEGF-C通过受体VEGFR-3促进组织生长、抑制分化,促进肿瘤细胞间质淋巴管和血管生成,是促使宫颈癌发生扩散和转移的重要原因。二者阳性表达可预示预后不良。     

子宫内膜癌中Maspin的表达及其与雌激素受体表达的相关性研究

目的:检测Maspin蛋白在正常子宫内膜、不典型增生及内膜癌组织中的表达,及其与雌激素受体(ER)表达的关系,探讨Maspin在子宫内膜癌发生中的作用及其作用机制。方法:免疫组化SP法检测40例子宫内膜腺癌、18例不典型增生及10例正常子宫内膜(对照组)中Maspin蛋白的表达及其与子宫内膜癌患者临床病理特征和ER蛋白表达的关系。结果:Maspin阳性表达在正常子宫内膜组最高(9/10,90%),高于内膜不典型增生组(10/18,55.6%)和内膜癌组(17/40,42.5%),差异有统计学意义(P<0.05),在内膜癌中FIGOⅠ期的表达(13/20,65.0%)明显高于Ⅱ~Ⅲ期(4/20,20.0%;P<0.05),无淋巴结转移者(17/34,50.0%)明显高于有淋巴结转移者(0/6;P=0.030),但与组织学分级及肌层浸润程度无关(P>0.05)。ER在正常子宫内膜、内膜不典型增生及内膜癌组织的阳性表达率分别为(10/10,100.0%)、(13/18,72.2%)和(20/40,50.0%),各组间差异有统计学意义(P<0.05);内膜癌组织中FIGOⅠ期的表达(14/20,70.0%)明显高于Ⅱ~Ⅲ期(6/20,30.0%;P<0.05);内膜癌高、中、低分化组中ER表达率分别为(11/15,73.3%)、(8/18,44.4%)、(1/7,14.3%),组间差异有统计学意义(P<0.05);无淋巴结转移者(20/34,58.8%)明显高于有淋巴结转移者(0/6;P=0.020),肌层浸润≤1/2者(16/24,66.7%)明显高于肌层浸润>1/2者(4/16,25.0%;P<0.05)。子宫内膜癌中,Maspin的表达与ER的表达存在正相关关系(r=0.394,P<0.05)。结论:从正常子宫内膜、内膜不典型增生到内膜癌,Maspin蛋白表达逐渐降低,且其低表达与子宫内膜癌临床分期晚、淋巴结转移有关,并与ER蛋白表达呈一致性,提示Maspin蛋白的表达可能受雌激素调控,参与了子宫内膜癌发生发展和转移过程。     

Matrix metalloproteinases-2 and -9 in cervical cancer: different roles in tumor progression

The incidence of uterine cervical cancer has increased slightly in Western countries, with an increase in relatively young women. Overexpression of matrix metalloproteinases (MMPs)-2 and -9 has turned out as a prognostic factor in many cancers. We compared the expression of the proteins MMP-2 and MMP-9 in cervical primary tumors with clinical outcome and risk factors of cervical cancer. One hundred sixty-one patients with cervical cancer treated in Ume? University Hospital or Sahlgrenska University Hospital, Sweden, between 1991 and 1995 were included in the study. Paraffin-embedded tissue samples obtained prior to treatment were examined immunohistochemically by specific antibodies for MMP-2 and MMP-9. Forty-two percent of the tumors were intensively positive for MMP-2 and 31% for MMP-9. Nineteen percent of the samples were intensively positive for both proteinases and 47% negative or weak for both. Overexpression of MMP-2 seemed to predict unfavorable survival under Kaplan-Meier analysis and in the multivariate analysis. Early sexual activity and low parity seemed to correlate to overexpression of MMP-2. MMP-9 was not associated with survival or sexual behavior. Intensive MMP-9 was noted in grade 1 tumors. We conclude that MMP-2 and MMP-9 have different roles in uterine cervical cancer. MMP-2 could be associated with aggressive behavior, but MMP-9 expression diminishes in high-grade tumors.     

酸性成纤维细胞生长因子在宫颈癌中的表达及其信号传导途径

目的探讨酸性成纤维细胞生长因子(aFGF)在宫颈癌发生发展中的作用及其信号传导机制.方法应用逆转录-聚合酶链反应技术(RT-PCR)对36例宫颈癌组织aFGF 及其受体FGFR1的表达进行了分析;并以不同浓度的aFGF 和酪氨酸蛋白激酶(TPK)抑制剂genistein诱导宫颈癌细胞株HeLa细胞,[γ-32P]ATP掺入外源性底物的方法,液体闪烁测定蛋白激酶C(PKC)及细胞外信号调节激酶(ERK)的活性.结果 aFGF mRNA 和FGFR1 mRNA在宫颈癌组织中的半定量检测结果分别为(1.233±0.064)和(1.168±0.103),与正常宫颈组织相比,差异有显著性(P<0.05),且在Ⅲ～Ⅳ期宫颈癌中的表达水平明显高于Ⅰ～Ⅱ期(P<0.05);随着aFGF浓度的增加,HeLa细胞PKC及ERK 活性随之升高,与aFGF浓度呈剂量依赖效应;genistein抑制细胞内PKC及ERK 活性,与genistein 浓度亦呈剂量依赖效应.结论提示aFGF 与宫颈癌的发生、发展、浸润呈正相关,其受体具有TPK活性,TPK激活后可进一步激活PKC和ERK,进一步证明PKC及ERK确是TPK的下游信号分子.     

Expression of glucose transporter-1 in cervical cancer and its precursors

OBJECTIVE: Increased glucose uptake and utilization is a known phenomenon exhibited by malignant cells. Overexpression of the glucose transporter protein family is thought to be the principal mechanism by which these cells achieve up-regulation. Our purpose is to determine glucose transporter-1 (GLUT 1) expression in squamous carcinoma of the cervix and precursor lesions. METHODS: Archival histologic sections were obtained from 31 cases of invasive squamous cell carcinoma (SCC) of the uterine cervix, 15 cases of high-grade cervical intraepithelial neoplasia, 5 cases of low-grade, and 9 normal cervices. Immunohistochemistry for GLUT 1 protein was performed using polyclonal GLUT 1 antibody (Dako, Carpinteria, CA) and the labeled streptavidin-biotin procedure. RESULTS: Compared to the internal control, the pattern of staining varied from weak (1+) to strong (3+) reactions. In normal cervix, 1+ GLUT 1 staining was seen in the basal cells of the squamous epithelium. All 31 (100%) cases of SCC were positive for GLUT 1. Positive reactions seemed more intense in tumor cells that were farther away from the stromal blood supply. There was a correlation between intensity of reaction for GLUT 1 and histologic grade of tumor (P = 0.0027) and with progression from normal or dysplastic lesions to invasive cancer (P = 0.0001). Intensity was a predictor of the presence of poorly differentiated tumor type. Low-grade CIN staining was seen in less than one-third of the epithelium, while in high-grade lesions the reaction was present in over one-half of the epithelium. CONCLUSIONS: GLUT 1 is overexpressed in cervical carcinoma. The process appears to be related to grade of tumor but not to the progression from preneoplastic lesions. The results suggest that GLUT 1 overexpression is a late phenomenon in cellular transformation. Furthermore, the possible relation of expression to tumor blood supply suggests that the malignant cells may have an adaptive environmental ability to compensate for a compromised microenvironment.     

FHIT在宫颈癌及宫颈上皮内瘤变的表达及意义

目的:探讨在宫颈癌和宫颈上皮内瘤变(cervical intraepithelial neoplasia,CIN)发生中脆性组氨酸三联体(fragile histid ine triad,FHIT)基因表达异常的作用及与HPV感染的关系。方法:用免疫组化法检测67例宫颈癌、42例CINⅢ和35例正常宫颈上皮组织的FHIT的表达。用PCR法检测宫颈癌石蜡组织中的HPV DNA,并用直接测序法或反向核酸杂交法对HPV分型。结果:正常宫颈组织中FHIT基因表达下调率为8.6%,CINⅢ组为28.57%,宫颈癌组为46.27%,差异均有统计学意义(P<0.05)。CINⅢ组FHIT蛋白表达下调率虽比宫颈癌组为低,但组间无统计学差异(P=0.66)。67例宫颈癌病例中,高危型HPV感染阳性者的FHIT表达下降或缺失占55.32%,明显高于无高危型HPV感染者(20%)(P<0.05)。宫颈癌患者的年龄、临床分期、肿瘤组织学分级、肿瘤浸润深度和淋巴结转移与FHIT蛋白表达均无明显相关(P>0.05)。FHIT表达下调或缺失31例宫颈癌患者的5年生存率为77.1%,FHIT正常表达36例的5年生存率为79.3%(P>0.05)。结论:FHIT在宫颈癌及CINⅢ中的表达明显下调,可能与HPV感染协同在宫颈癌的发生中起了重要作用。而FHIT在宫颈癌发展中的作用及与预后的关系,有待大样本的进一步研究。     

The role of co-factors in the progression from human papillomavirus infection to cervical cancer

ObjectiveCo-factors for cervical cancer, including oral contraceptive (OC) use, smoking and multiparity have been identified; however, the stage at which they act in cervical carcinogenesis is not clear. We compared established risk factors among women with CIN2 and CIN3 to evaluate the heterogeneity of these factors in precancer and also assessed their role during cervical carcinogenesis.MethodsThe current analysis included 2783 women with various stages of cervical disease who were enrolled in the Study to Understand Cervical Cancer Early Endpoints and Determinants (SUCCEED) and the Biopsy Study. Associations of co-factors within cervical precancer and at different stages of cervical carcinogenesis were estimated using logistic regression.ResultsLong-term OC use (10 + years vs. never: OR = 2.42, 95% CI: [1.13–5.15]), multiparity (3 + births vs. nulliparous: OR = 1.54 [1.04–2.28]), smoking (ever vs. never: OR = 1.95 [1.48–2.58]), and no Pap test in the previous five years (2.05 [1.32–3.17]) were positively associated with CIN3 compared to CIN2. We observed that long-term OC use, parity and smoking were associated with an increased risk of CIN3 compared to < CIN2 (1.97 [1.12–3.46]; 2.23 [1.59–3.11]; 2.60 [2.04–3.30], respectively), whereas associations were not significantly different (OC use, parity) or showed decreased risk (smoking) when comparing cancer to CIN3.ConclusionsDifferences in established risk factors suggest that CIN3 is a more specific definition of precancer than CIN2. Hormonally-related factors and smoking play a role in the transition from human papillomavirus infection to precancer.     

Stromal cells play a role in cervical cancer progression mediated by MMP-2 protein

Metalloproteinases, especially metalloproteinase-2 (MMP-2), are known for their role in the degradation of the extracellular matrix. Nevertheless, a thorough understanding of MMP-2 expression in neoplastic lesions of the uterine cervix has yet to be accomplished. This study aimed to analyze the MMP-2 expression in cervical intraepithelial neoplasia III (CIN3) and in cervical squamous cell carcinoma, in tumor cells and adjacent stromal cells. MMP-2 expression was assessed by an immunohistochemical technique. MMP-2 expression was greater in the stromal cells of invasive carcinomas than in CIN3 (p < 0.0001). MMP-2 expression in stromal cells correlates with the clinical stage, gradually increasing as the tumor progresses (p = 0.04). This study corroborates that stromal cells play an important role in tumor invasion and progression, mediated by the progressive enhancement of MMP-2 expression from CIN3 to advanced invasive tumor. The intense MMP-2 expression most probably is associated with poor tumor prognosis.     

Expression and transcriptional profiling of the LKB1 tumor suppressor in cervical cancer cells

Objectives

To characterize the biological activities of LKB1, examine LKB1 protein expression and identify LKB1-regulated genes that may serve as therapeutic targets in cervical cancer.

Methods

Proliferation of cervical cancer HeLa cells expressing LKB1 was examined. LKB1 expression in normal cervical tissues and cervical cancers was assessed by immunohistochemistry. Gene expression profiles of cervical cancer HeLa cells stably expressing LKB1 were analyzed by microarray. Differentially expressed genes were analyzed using Gene Ontology (GO) terms and the Kyoto Encyclopedia of Genes and Genomes (KEGG) PATHWAY database. Quantitative RT-PCR was used to validate the microarray data. The expression of lipid phosphatase inositol polyphosphate 4-phosphatase type II (INPP4B) was confirmed by western blotting.

Results

Expression of LKB1 inhibited HeLa cell proliferation, activated AMPK and was lost in more than 50% of cervical carcinomas. More than 200 genes were differentially expressed between HeLa cells with and without LKB1. Bioinformatics analysis with GO annotation indicated that LKB1 plays a role in receiving diverse stimuli and converting them into molecular signals. KEGG PATHWAY analysis showed that 8 pathways were significantly regulated. These include arginine and proline metabolism and inositol phosphate metabolism. The differential expression of 7 randomly selected genes was confirmed by quantitative RT-PCR. Furthermore, the steady-state level of INPP4B protein was up-regulated in LKB1-overexpressing cells.

Conclusions

This study establishes LKB1 as an important tumor suppressor in cervical cancer and sheds light on a novel signaling pathway regulated by LKB1.     

COX-2和VEGF-C在宫颈癌中的表达及其意义

目的探讨环氧合酶2(COX2)、血管内皮生长因子C(VEGFC)在宫颈癌及正常宫颈组织的表达情况及其与宫颈癌生物学行为之间的关系。方法采用免疫组化SP法检测郑州大学第一附属医院2000年1月至2003年3月期间76例宫颈癌和19例正常宫颈组织中COX2、VEGFC的表达。结果COX2和VEGFC蛋白在宫颈癌和正常宫颈组织中的表达差异有显著性意义(P<001);COX2表达与宫颈癌淋巴结转移、组织学分级和组织学类型显著相关,VEGFC的表达与淋巴结转移、组织学分级和临床分期显著相关。COX2与VEGFC的表达之间呈正相关(r=0553,P<001)。结论COX2和VEGFC2种蛋白表达与宫颈癌的发生发展相关,并对宫颈癌的淋巴结转移可能起重要作用。     

E-cadherin and alpha-catenin expression during tumor progression of cervical carcinoma

OBJECTIVE: The objective of this study was to determine whether a relationship between the E-caherin molecule and the E-cadherin-associated cytoplasmic molecule, alpha-catenin, could provide additional information in the neoplastic progression of cervical cancer. METHODS: In this study we investigated by immunohistochemistry E-cadherin (E-cad) and alpha-catenin (alpha-cat) expression in 57 cervical biopsy samples representative of normal exocervical epithelium, viral (human papillomavirus (HPV) infection) and dysplastic lesions (low- and high-grade lesions), and invasive squamous cell carcinoma. The presence of immunostaining and the pattern of distribution of these molecules were correlated with the histological diagnosis (normal cervical epithelium vs HPV, cervical intraepithelial neoplasia (CIN), and invasive carcinoma). RESULTS: The correlation between alpha-cat expression and the histological diagnosis was statistically significant (chi2 test, P < 0.0077); moreover, E-cad and alpha-cat distributions were significantly correlated with the histological classification (P < 0.0001 and P < 0.0043, respectively). CONCLUSION: These results suggest that not only E-cad but also alpha-cat are associated with the loss of differentiation in CIN and squamous cell carcinomas; thus the coexpression of E-cad and alpha-cat may represent a discriminant of malignant potential and could provide an additional criterion to define high-grade CIN.     

Expression of chemokine CXCL12 and its receptor CXCR4 in human epithelial ovarian cancer: an independent prognostic factor for tumor progression

OBJECTIVES: Chemokine CXCL12 and its unique receptor CXCR4 have been recently implicated in cancer metastasis. Our goal was to explore expression of CXCL12 and CXCR4 protein in normal ovarian surface epithelium, primary tumors and paired metastases of epithelial ovarian cancer as well as its association with clinicopathological features. We also wanted to test if expression of CXCR4 has prognostic value in epithelial ovarian cancer patients. METHOD: Sections from 6 normal ovarian surface epithelium, 44 primary epithelial ovarian tumors and 30 paired metastatic tumors in omentum were evaluated for CXCL12 and CXCR4 expression using immunohistochemistry (IHC). RESULTS: All samples of normal ovarian surface epithelium were negative for CXCL12 and CXCR4 protein. Ovarian cancer cells mainly showed cytoplasmic staining of CXCL12 and CXCR4. CXCL12 and CXCR4 staining were detected in 40/44 (91%) and 26/44 (59%) patients with primary epithelial ovarian tumors respectively. CXCR4 expression in primary tumors had no significant correlation with lymph nodes metastasis. However, if we combined CXCR4 expression in primary tumors with metastatic tumors, a significant correlation with lymph nodes metastasis was found (P = 0.018). The intensity of CXCL12 staining correlated with ascites (P = 0.014). The rate of CXCR4 expression in refractory and recurrent group (81% versus 28%, P = 0.0008) was significantly higher than that in no-recurrent group. After a median follow-up of 37 months, CXCR4 expression was found associated with an unfavorable prognosis with significantly reduced median disease progression-free survival and overall survival of 15 and 27 months (P = 0.0004, P = 0.017) respectively. Median time-to-event was not reached in patients with negative CXCR4 staining. In multivariate analysis, CXCR4 expression and residual tumor size emerged as independent prognostic factors in epithelial ovarian cancer patients. CONCLUSIONS: This article provides the first evidence that CXCR4 expression could be an independent prognostic factor for epithelial ovarian cancer patients.     

Downregulation of miR-599 predicts poor outcome in cervical cancer patients and promotes the progression of cervical cancer

ObjectiveCervical cancer remains a leading cause of gynecological cancer-related death. In this study, we aimed to investigate the expression pattern of miR-599 and its prognostic significance in cervical cancer.Materials and methodsThe RT-qPCR analysis was used to detect the expression levels of miR-599 in cervical cancer tissues and cell lines. The association between miR-599 expression and clinical characteristics of cervical cancer patients was analyzed using the χ² test. The Kaplan–Meier analysis and multivariate Cox proportional hazards model were used to explore the prognostic significance of miR-599. Then, CCK-8 assays, transwell migration, and invasion assays were used to assess the effects of miR-599 on tumor cell proliferation, migration, and invasion of cervical cancer cells, respectively.ResultsmiR-599 expression was significantly downregulated in cervical cancer tissues and cells compared with non-cancerous tissues and HaCaT cells, respectively. Statistical analysis revealed that miR-599 expression was associated with lymph node metastasis and FIGO stage. The miR-599 expression was an independent prognostic factor for overall survival. Functionally, overexpression of miR-599 suppressed cell proliferation, migration, and invasion of cervical cancer cells, while downregulation of miR-599 had opposite effects.ConclusionmiR-599 acts as a tumor suppressor in cervical cancer that inhibiting cell proliferation, migration, and invasion of cervical cancer cells, suggesting that miR-599 may be a potential prognostic biomarker and novel targeted strategy for cervical cancer.     

Netrin-1在HeLa细胞的表达及对HeLa细胞功能的影响

目的:研究Netrin-1在HeLa细胞的表达及对HeLa细胞增殖、侵袭和凋亡的影响。方法:利用蛋白质印迹法检测Netrin-1在HeLa细胞的表达,并通过MTT、侵袭实验和流式细胞仪分别检测10,50和100ng/mlNetrin-1对HeLa细胞增殖能力、侵袭能力和凋亡的影响。结果:(1)Netrin-1在HeLa细胞有表达,其相对表达量为0.389±0.026;(2)MTT实验结果显示,Netrin-1可以促进HeLa细胞增值,表现为时间和剂量依赖性,与对照组有显著差异(P<0.05或P≤0.01);(3)Netrin-1处理组细胞迁移数分别为314±16,487±15和553±19,均明显多于对照组180±10(P均<0.05);(4)在Netrin-1干预下,HeLa细胞凋亡率呈递减趋势,与对照组比较有显著差异(P<0.05或P<0.01)。结论:HeLa细胞表达的Netrin-1与宫颈癌的侵袭转移有关,Netrin-1促进HeLa细胞增殖和侵袭能力,并抑制HeLa细胞凋亡,可能为未来宫颈癌的治疗提供依据。     

Usefulness of magnetic resonance in evaluation of cervical cancer progression

Magnetic resonance belongs to a group of modern diagnostic methods which, together with classic gynecological, transvaginal ultrasound and histopathological examinations, should be routinely used in patients with suspicion or diagnosed cervical malignancies. The procedure allows precise localization and staging of the tumor as well as evaluation of the volume of the local lymph nodes. Obtained data are useful in selection of optimal therapy and evaluation of cancer progression. Intravenous injection of the paramagnetic contrast media significantly increases diagnosis accuracy especially of small lesions. It is also helpful in differentiation of post-radiotherapy changes and malignant infiltration. The new applications, such as diffusion weighted imaging, magnetic resonance spectroscopy and fat or water saturation are also widely used to improve final diagnosis. The endovaginal receiver coil allows high spatial resolution imaging of the cervix, which is particularly useful in very small, controversial lesions.     

Expression of 67-kDa laminin receptor was associated with tumor progression and poor prognosis in epithelial ovarian cancer

Objective

67-kDa laminin receptor (67LR) has been identified as a prognostic biomarker for a variety of human cancers. We investigated the clinical significance of 67LR expression and its functional role in epithelial ovarian cancer (EOC).

Methods

67LR expression was evaluated by immunohistochemistry in 62 patients with EOC. We assessed the correlation of 67LR expression with clinical characteristics. In vitro experiment was performed for 67LR with inhibition using siRNA to evaluate its role in cell survival, apoptosis, and invasion in EOC cells.

Results

67LR was predominantly expressed on the cell membrane in the majority of EOC samples (45/62, 73%). 67LR expression was significantly correlated with advanced stage (P = 0.001). Patients with 67LR expression had shorter progression-free survival among all the patients (P = 0.010) and in particular among patients with advanced stages (P = 0.046). When 67LR expression was inhibited by siRNA in EOC cells (HeyA8 and A2780), there was a significant decrease of cell proliferation and invasion as well as increase of apoptosis.

Conclusion

These findings suggest that 67LR expression may play an important role in tumor progression into advanced stage with poor prognosis in EOC and down-regulation of 67LR on tumor cells may be a therapeutic target in those patients.