VEGF-A and VEGFR-3 correlate with nodal status in operable non-small cell lung cancer: inverse correlation between expression in tumor and stromal cells

Adaptive resistance of tumor cells to anti-vascular endothelial growth factor therapy: A reversible phenomenon

Vascular endothelial growth factor (VEGF) inhibition is an essential targeted strategy for malignant tumors, but its efficacy is severely constrained by drug resistance. The traditional view holds that the target of VEGF inhibition is endothelial cells, and thus compensatory angiogenesis is considered the main mechanism of drug resistance. In this study, we found that tumor cells themselves could develop acquired resistance to VEGF therapy, indicating an independent resistance mechanism apart from angiogenesis. Notably, this acquired resistance was temporary, disappearing completely four days after discontinuing exposure to the drug in vitro. Our findings suggest that tumor cells may also be targets of VEGF inhibition, and their response to treatment should not be overlooked in contributing to drug resistance.

Advances in lymphatic metastasis of non-small cell lung cancer

Lung cancer is a deeply malignant tumor with high incidence and mortality. Despite the rapid development of diagnosis and treatment technology, abundant patients with lung cancer are still inevitably faced with recurrence and metastasis, contributing to death. Lymphatic metastasis is the first step of distant metastasis and an important prognostic indicator of non-small cell lung cancer. Tumor-induced lymphangiogenesis is involved in the construction of the tumor microenvironment, except promoting malignant proliferation and metastasis of tumor cells, it also plays a crucial role in individual response to treatment, especially immunotherapy. Thus, this article reviews the current research status of lymphatic metastasis in non-small cell lung cancer, in order to provide some insights for the basic research and clinical and translational application in this field.

Correlation between the Expression of VEGF and Ki67 and Lymph Node Metastasis in Non-small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Background

Lymph node metastasis is the most common and important way of metastasis in NSCLC and is also the most important factor affecting lung cancer stage and prognosis. It is very important to analyze the relationship between the expression of vascular endothelial growth factor (VEGF) and Ki67 and lymph node metastasis (LNM) in non-small-cell lung cancer (NSCLC).

Methods

We searched the PubMed, EMBASE, and Cochrane Library and conducted meta-analyses using the R meta-package. Relative risk (RR) with a 95% confidence interval (95% CI) was the main indicator.

Results

Totally, 18 studies were considered eligible, with 4521 patients, including 1518 LNM-positive patients and 3033 LNM-negative patients. The incidence of LNM in Ki67-negative patients was lower than that in Ki67-positive patients (RR = 0.66, 95% CI: 0.44, 0.98). The incidence of LNM in VEGF-A-negative patients was lower than that in VEGF-A-positive patients (RR = 0.64, 95% CI: 0.49, 0.83). The incidence of LNM in VEGF-C negative patients was lower than that in VEGF-C positive patients (RR = 0.68, 95% CI: 0.53, 0.88). The incidence of LNM in VEGF-D negative and positive patients were of no significant differences (RR = 0.84, 95% CI: 0.61, 1.14).

Conclusion

The high expression of Ki67, VEGF-A, and VEGF-C significantly increases the risk of lymph node metastasis in NSCLC, while the VEGF-D expression has no correlation with lymph node metastasis. The expression levels of Ki67, VEGF-A, and VEGF-C show a good potential for lymph node metastasis prediction.

Expression of VEGFR-3 in intrahepatic cholangiocarcinoma correlates with unfavorable prognosis through lymphangiogenesis

Background & aims: VEGFR-3 has been shown of great significance in lymph node metastasis and some malignancies, however, its expression in tumors and impact on outcome of intrahepatic cholangiocarcinoma (iCCA) remains unknown. The aim of this study was to assess the role of VEGFR-3 positive tumors for prognosis of iCCA and tumor-associated lymphangiogenesis.

Methods: Clinicopathological features, prognostic factors and survival rate were analyzed to evaluate the influence of VEGFR-3 positive expression on prognosis of iCCA. In addition, tumor-associated lymphangiogenesis quantified as micro-lymphatic vessel density (MLVD) was assessed to explore the correlation between VEGFR-3 expression and lymph node metastasis for iCCA.

Results: Patients with VEGFR-3 positive tumors had increased lymph node metastasis (p=0.025) and were more likely to suffer from tumor recurrence compared with VEGFR-3 negative tumors (p<0.001). VEGFR-3 expression in tumors was identified as an independent prognostic factor for both overall and recurrence-free survival in surgical resected patients with iCCA. In addition, higher MLVD was significantly associated with VEGFR-3 positive expression in tumors (p<0.001), which facilitate lymph node metastasis and significantly worse survival rates.

Conclusions: Our study reveals that VEGFR-3 positive expression in tumors represents an independent prognostic factor for both overall and recurrence-free survival in hepatic resected patients with iCCA. VEGFR-3 positive tumors favor lymph node metastasis, tumor recurrence and worse outcomes through tumor-associated lymphangiogenesis.

Ultrasonic diagnosis combined with targeted ultrasound contrast agent improves diagnostic sensitivity of ultrasonic for non-small cell lung cancer patients

Non-small cell lung cancer (NSCLC) is one of the most prevalent human cancers, which is known for local growth, easily migration, long-distance invasion and reoccurrence. Targeted ultrasound (US) contrast combined with ultrasound for lung cancer diagnosis has been applied in the clinic. In the present study, a novel targeted ultrasound contrast agent containing chistosan/Fe₃O₄-parceled bispecific antibody (TcBab) targeting carcino-embryonic antigen, vascular endothelial growth factor receptor was introduced, and the diagnostic accuracy and sensitivity was investigated in patients with NSCLC. A total of 384 patients with suspected NSCLC were recruited to investigate the accuracy of TcBab-ultrasound (TcBab-US) and ultrasound. Results demonstrated that TcBab-US improved sensitivity and may provide a novel protocol for diagnosing tumors in patients with suspected NSCLC at an early stage. Data analysis demonstrated that TcBab-US diagnosed 154 suspected patients with NSCLC, whereas ultrasound only diagnosed 84 suspected patients with NSCLC out of a total of 384 patients with suspected NSCLC (P<0.01). A dosage experiment revealed that the optimal dose of TcBab was 5 mg/kg for NSCLC patients. Pharmacodynamics analysis showed that TcBab may be metabolized within 16 h in serum of patients. Notably, early diagnosis determined by TcBab-US contributed to improvement of survival for NSCLC patients as determined by a comparison of the survival rate with the survival rate of patients who did not receive TcBab (P<0.05). In conclusion, these investigations suggested that TcBab improves the accuracy and diagnostic confidence of ultrasonic for the diagnosis of early-stage NSCLC, and may have potential application value in the clinic.

Co-expression of PDGF-B and VEGFR-3 strongly correlates with poor prognosis in hepatocellular carcinoma patients after hepatectomy

BACKGROUND

The ability to evaluate the prognosis of hepatocellular carcinoma (HCC) patients following hepatectomy with biological markers is of great importance.

METHODS

In this study, we collected samples from 90 patients with HCC after hepatectomy. Immunohistochemistry was used to detect the expression of PDGF-B and VEGFR-3 in these HCC samples.

RESULTS

According to the immunohistochemical results, PDGF-B and VEGFR-3 staining were significantly associated with clinical features. Additionally, a significant association between high PDGF-B and VEGFR-3 levels and shorter overall survival was noted, when PDGF-B and VEGFR-3 co-expression been analyzed.

CONCLUSION

These results suggest that the correlative expression level of PDGF-B and VEGFR-3 has strong value in the prognosis of HCC patients following hepatectomy.

Lymphatics-associated genes are downregulated at transcription level in non-small cell lung cancer

The present study aimed to verify a possibility of ongoing lymphangiogenesis in non-small cell lung cancer (NSCLC) via examination of mRNA levels of a number of lymphangiogenesis-associated genes in tumors. It was hypothesized that transcriptional activation of these genes would occur in tumors that stimulate new lymphatic vessel formation. The study was performed on 140 pairs of fresh-frozen surgical specimens of cancer and unaffected lung tissues derived from NSCLC stage I-IIIA patients. mRNA levels were evaluated with the reverse transcription-quantitative polymerase chain reaction method and expressed as fold change differences between the tumor and normal tissues. Possible associations between expression and patient clinicopathological characteristics and survival were analyzed. In the NSCLC tissue samples, vascular endothelial growth factor (VEGF) C, VEGFD, VEGFR3, VEGFR2, VEGFR1, lymphatic vessel endothelial hyaluronan receptor 1, integrin subunit α 9, FOX2, neuropilin 2, fibroblast growth factor 2 genes were significantly downregulated (P<0.001 for all) compared with matched normal lung tissues, whereas mRNA levels for VEGFA, spleen associated tyrosine kinase, podoplanin, and prospero homeobox 1 genes were similar in both tissues. Neither lymph node status, nor disease pathological stage influenced expression, whereas more profound suppression of gene activities appeared to occur in squamous cell carcinomas compared with adenocarcinomas. The VEGFR1 mRNA expression level was significantly connected with patient survival in the univariate analysis, and was an independent prognostic factor for overall survival in the multivariate Cox's proportional hazards model (HR 2.103; 95% confidence interval: 1.005-4.401; P=0.049). The results support a hypothesis of absence of new lymphatic vessel formation inside growing NSCLC tumor mass, however do not exclude a possibility of lymphangiogenesis in narrow marginal tumor parts.

Diagnostic and therapeutic implications of the vascular endothelial growth factor family in cancer

Cancer progression is attained by uncontrolled cell division and metastasis. Increase in tumor size triggers different vascular channel formation to address cell nutritional demands. These channels are responsible for transferring of nutrients and gaseous to the cancer cells. Cancer vascularization is regulated by numerous factors including vascular endothelial growth factors (VEGFs). These factors play an important role during embryonic development. Members included in this group are VEGFA, VEGFB, VEGFC, PIGF and VEGFD which markedly influence cellular growth and apoptosis. Being freely diffusible these proteins act in both autocrine and paracrine fashions. In this review, genetic characterization these molecules and their putative role in cancer staging has been elaborated. Prognostic significance of these molecules along with different stages of cancer has also been summarized. Brief outline of ongoing efforts to target hot spot target sites against these VEGFs and their cognate limitations for therapeutic implications are also highlighted.

Different roles of myofibroblasts in the tumorigenesis of nonsmall cell lung cancer

Myofibroblasts play a critical role in the cancer cell growth, invasion, and tumor-associated vascularization during the carcinogenesis of nonsmall cell lung cancer (NSCLC), whereas the underlying molecular bases are not completely understood. We isolated Lin-negative, Sca1-low, and CD49e-high myofibroblasts from the NSCLC tissues of the patients and modified the levels of either transforming growth factor β 1 (TGFβ1) or vascular endothelial growth factor A (VEGF-A) in these cells. We found that coculture with TGFβ1-overexpressing myofibroblasts significantly decreased the NSCLC cell growth in an MTT assay through proliferation suppression rather than modulation of cell apoptosis, while significantly increased the NSCLC cell invasiveness in either a transwell migration assay or a scratch wound healing migration assay. However, modulation of TGFβ1 levels in myofibroblasts did not significantly alter vessel formation in a human umbilical vein endothelial cells (HUVECs) transwell collagen gel assay. On the other hand, overexpression of VEGF-A in myofibroblasts significantly increased vessel formation in the HUVECs transwell collagen gel assay. Together, these data suggest that myofibroblasts may regulate cancer cell growth and invasion through TGFβ1 but modulate cancer-associated neovascularization through VEGF-A. Hence, targeting different signaling pathways in myofibroblasts may delicately control NSCLC growth and invasion.

Lymphangiogenic Markers and Their Impact on Nodal Metastasis and Survival in Non-Small Cell Lung Cancer--A Structured Review with Meta-Analysis

Background

In non-small cell lung cancer (NSCLC), nodal metastasis is an adverse prognostic factor. Several mediating factors have been implied in the development of nodal metastases and investigated for predictive and prognostic properties in NSCLC. However, study results differ. In this structured review and meta-analysis we explore the published literature on commonly recognized pathways for molecular regulation of lymphatic metastasis in NSCLC.

Methods

A structured PubMed search was conducted for papers reporting on the expression of known markers of lymhangiogenesis in NSCLC patients. Papers of sufficient quality, presenting survival and/or correlation data were included.

Results

High levels of vascular endothelial growth factor C (VEGF-C, HR 1.57 95% CI 1.34–1.84) and high lymphatic vascular density (LVD, HR 1.84 95% CI 1.18–2.87) were significant prognostic markers of poor survival and high expression of VEGF-C, vascular endothelial growth factor receptor 3 (VEGFR3) and LVD was associated with lymph node metastasis in NSCLC.

Conclusion

Lymphangiogenic markers are prognosticators of survival and correlate with lymph node metastasis in NSCLC. Their exact role and clinical implications should be further elucidated.

Downregulation of miR-126 induces angiogenesis and lymphangiogenesis by activation of VEGF-A in oral cancer

Background:

MicroRNA (miRNA)-126 (miR-126) is an endothelial-specific miRNA located within intron 7 of epidermal growth factor-like domain 7 (EGFL7). However, the role of miR-126 in cancer is controversial.

Methods:

We examined the function of miR-126 in oral squamous cell carcinoma (OSCC) cells. Furthermore, a series of 118 cases with OSCC were evaluated for the expression levels of miR-126.

Results:

MicroRNA-126 (miR-126) was associated with cell growth and regulation of vascular endothelial growth factor-A activity, and demethylation treatment increased expression levels of miR-126 and EGFL7 in OSCC cells. A significant association was found between miR-126 expression and tumour progression, nodal metastasis, vessel density, or poor prognosis in OSCC cases. In the multivariate analysis, decreased miR-126 expression was strongly correlated with disease-free survival.

Conclusion:

The present results suggest that miR-126 might be a useful diagnostic and therapeutic target in OSCC.

SAR131675, a potent and selective VEGFR-3-TK inhibitor with antilymphangiogenic, antitumoral, and antimetastatic activities

SAR131675 is a potent and selective VEGFR-3 inhibitor. It inhibited VEGFR-3 tyrosine kinase activity and VEGFR-3 autophosphorylation in HEK cells with IC(50) values of 20 and 45 nmol/L, respectively. SAR131675 dose dependently inhibited the proliferation of primary human lymphatic cells, induced by the VEGFR-3 ligands VEGFC and VEGFD, with an IC(50) of about 20 nmol/L. SAR131675 was found to be highly selective for VEGFR-3 versus 107 receptors, enzymes, ion channels, and 65 kinases. However, it was moderately active on VEGFR-2 with a VEGFR-3/VEGFR-2 ratio of about 10. SAR131675 had no antiproliferative activity on a panel of 30 tumors and primary cells, further showing its high specificity and indicating that SAR131675 is not a cytotoxic or cytostatic agent. SAR131675 was very well tolerated in mice and showed a potent antitumoral effect in several orthotopic and syngenic models, including mammary 4T1 carcinoma and RIP1.Tag2 tumors. Interestingly, it significantly reduced lymph node invasion and lung metastasis, showing its antilymphangiogenic activity in vivo. Moreover, treatment of mice before resection of 4T1 primary tumors was sufficient to prevent metastasis. Tumor-associated macrophages (TAM) play an important role in tumor growth and metastasis. The expression of VEGFR-3 on TAMs has been recently described. F4/80 immunostaining clearly showed that SAR131675 significantly reduced TAM infiltration and aggregation in 4T1 tumors. Taken together, SAR131675 is the first highly specific VEGFR-3-TK inhibitor described to date, displaying significant antitumoral and antimetastatic activities in vivo through inhibition of lymphangiogenesis and TAM invasion.

MicroRNA signatures in tumor tissue related to angiogenesis in non-small cell lung cancer

BACKGROUND

Angiogenesis is regarded as a hallmark in cancer development, and anti-angiogenic treatment is presently used in non-small cell lung cancer (NSCLC) patients. MicroRNAs (miRs) are small non-coding, endogenous, single stranded RNAs that regulate gene expression. In this study we aimed to identify significantly altered miRs related to angiogenesis in NSCLC.

METHODS

From a large cohort of 335 NSCLC patients, paraffin-embedded samples from 10 patients with a short disease specific survival (DSS), 10 with a long DSS and 10 normal controls were analyzed. The miRs were quantified by microarray hybridization and selected miRs were validated by real-time qPCR. The impacts of different pathways, including angiogenesis, were evaluated by Gene Set Enrichment Analysis (GSEA) derived from Protein ANalysis THrough Evolutionary Relationship (PANTHER). One of the most interesting candidate markers, miR-155, was validated by in situ hybridization (ISH) in the total cohort (n = 335) and correlation analyses with several well-known angiogenic markers were done.

RESULTS

128 miRs were significantly up- or down-regulated; normal versus long DSS (n = 68) and/or normal versus short DSS (n = 63) and/or long versus short DSS (n = 37). The pathway analysis indicates angiogenesis-related miRs to be involved in NSCLC. There were strong significant correlations between the array hybridization and qPCR validation data. The significantly altered angiogenesis-related miRs of high interest were miR-21, miR-106a, miR-126, miR-155, miR-182, miR-210 and miR-424. miR-155 correlated significantly with fibroblast growth factor 2 (FGF2) in the total cohort (r = 0.17, P = 0.002), though most prominent in the subgroup with nodal metastasis (r = 0.34, P<0.001).

CONCLUSIONS

Several angiogenesis-related miRs are significantly altered in NSCLC. Further studies to understand their biological functions and explore their clinical relevance are warranted.

Prognostic significance of epidermal growth factor receptor and vascular endothelial growth factor receptor in colorectal adenocarcinoma

The purpose of this study was to evaluate the association between the expression of growth factors and the clinicopathological variables of colorectal adenocarcinoma. Immunohistochemistry and fluorescence in situ hybridization (FISH) were used to evaluate the amplification and expression of epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), VEGF-D, VEGF receptor (VEGFR)-2, VEGFR-3, transforming growth factor (TGF)-β1, and insulin-like growth factor-1 receptor (IGF-1R) in a tissue microarray of 292 colorectal adenocarcinomas. The expression of EGFR, VEGF, VEGF-D, VEGFR-2 and VEGFR-3 was detected in 5.1%, 10.0%, 6.8%, 5.2%, and 57.2%. EGFR expression was associated with angioinvasion (p < 0.05) and lymph node metastasis (p < 0.005). VEGFR-3 expression was higher in the rectum than in the colon (p < 0.05). VEGF expression correlated with VEGF-D (p < 0.05) and VEGFR-3 (p < 0.005) expression, while VEGF-D expression showed no significant association with VEGFR-2 or VEGFR-3. EGFR amplification was present in 10.6% and was not associated with EGFR protein expression. VEGFR-2 and VEGFR-3 expression levels were related to poor patient survival. Stage, perineural invasion, and lymph node metastasis were independent prognostic factors based on a Cox analysis. VEGFR-2 and VEGFR-3 expression are markers of a poor prognosis in patients with surgically resected colorectal adenocarcinoma, whereas EGFR has a minor influence.

Prognostic impact of angiogenic markers in non-small-cell lung cancer is related to tumor size

BACKGROUND

It is thought that different families of angiogenic factors stimulate angiogenesis at different stages of tumor development. Our aim was to study whether the prognostic impact of vascular endothelial growth factors (VEGFs) and receptors (VEGFRs), platelet-derived growth factors (PDGFs) and receptors (PDGFRs) and fibroblast growth factor-2 (FGF-2) were associated with tumor size in non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Tumor tissue samples were obtained from 335 patients who had undergone resection for stage I-IIIA NSCLC, and tissue microarrays (TMAs) were constructed. Immunohistochemical techniques were used to evaluate the expression of VEGF-A, VEGF-C, VEGFR-2, VEGFR-3, PDGF-A, PDGF-B, PDGFR-α, PDGFR-β, and FGF-2. Tumor size was categorized using the same cutoffs as in the 7th TNM classification for lung cancer.

RESULTS

In multivariate analysis, high VEGFR-2 (HR, 1.87, [95% CI, 1.02-3.45]; P = .043), VEGFR-3 (HR, 2.18 [95% CI, 1.28-3.71]; P = .004) and the combination of high VEGF-A and high VEGFR-2 expression (low/low vs. high/high; HR, 3.28 [95% CI, 1.47-7.31]; P = .004) were independent negative prognostic factors in T2a tumors. High PDGF-B expression (HR, 11.72 [95% CI, 3.07-44.76]; P < .001) was an independent prognostic factor in T2b tumors.

CONCLUSION

The prognostic impact of angiogenic factors depend in part on tumor size. VEGF-A/VEGFR-2 and VEGFR-3 seem to have their main impact in T2a tumors, while PDGF-B is a strong and independent prognostic factor in T2b tumors.

HIF, hypoxia and the role of angiogenesis in non-small cell lung cancer

IMPORTANCE OF THE FIELD

The role of angiogenesis in the initiation and progression of NSCLC and the molecular alterations leading to the growth of tumor vasculature are areas of great interest and recent therapeutic success.

AREAS COVERED IN THIS REVIEW

VEGF and its receptors play critical roles in the development of tumor vasculature and can be targeted by agents such as bevacizumab in the treatment of NSCLC. Furthermore, tumor hypoxia and the expression of the hypoxia-inducible factor (HIF) family of proteins are also linked to poorer survival in these patients. Recent studies using genetically engineered mouse models expressing stabilized HIF validate the importance of HIF in the evolution of NSCLC and demonstrate genetically that HIF is involved in NSCLC.

WHAT THE READER WILL GAIN

An overview of the key pathways and mediators of tumor angiogenesis, their relevance to the pathogenesis of NSCLC, and an update on the current status of angiogenesis inhibitors in NSCLC.

TAKE HOME MESSAGE

Angiogenesis is a key mediator of NSCLC progression. Several antiangiogenic strategies are in clinical use and under development. While candidate predictive biomarkers of response to antiangiogenic therapy exist, they await independent and prospective validation.

Independent and tissue-specific prognostic impact of miR-126 in nonsmall cell lung cancer: coexpression with vascular endothelial growth factor-A predicts poor survival

BACKGROUND

Angiogenesis is pivotal in tumor development. Vascular endothelial growth factor-A (VEGF-A) is considered one of the most important angiogenic factors, but lately several microRNAs (miRs) have been associated with vascular development. miR-126 has been related to tumor angiogenesis and in the regulation of VEGF-A. The authors aimed to investigate the prognostic impact of miR-126 and its co-expression with VEGF-A in nonsmall cell lung cancer (NSCLC) patients.

METHODS

Tumor tissue samples from 335 resected stage I to IIIA NSCLC patients were obtained and tissue microarrays (TMAs) were constructed with 4 cores from each tumor specimen. VEGF-A expression was evaluated by immunohistochemistry, and in situ hybridization was used to evaluate the expression of miR-126.

RESULTS

In the total material, miR-126 was a significant negative prognostic factor in both univariate (P = .005) and multivariate analyses (hazard ratio [HR] 1.8, 95% confidence interval [CI] 1.2-2.8, P = .01). Stratified by histology, miR-126 was only significant in squamous cell carcinomas (univariate: P < .001; multivariate: HR 3.1, CI 95% 1.7-5.6, P<.001). Stratified by lymph node status, miR-126 was significant only in the lymph node-positive subgroup (univariate: P<.001; multivariate: HR 4.1, CI 95% 2.0-8.4, P < .001). High miR-126 expression correlated significantly with high VEGF-A expression (P = .037). The co-expression of miR-126 and VEGF-A had a significant prognostic impact (P = .002), with 5-year survival rates of 68%, 51%, and 42% for low/low (n = 150), mixed combinations (n = 129), and high/high (n = 35) expression, respectively.

CONCLUSIONS

miR-126 is a strong and independent negative prognostic factor in NSCLC, and its prognostic impact appears related primarily to histology and nodal status.

Association between lymphangiogenesis-/micrometastasis- and adhesion-related molecules in resected stage I NSCLC

BACKGROUND

The purpose of this study was to clarify the role and clinical significance of lymphangiogenesis/micrometastases and adhesion molecules in resected stage I non-small cell lung cancer (NSCLC).

METHODS

Immunohistochemical (IHC) staining was used to analyze the protein expression of vascular endothelial growth factor-C (VEGF-C), VEGF, E-cadherin, alpha-catenin, beta-catenin, and gamma-catenin in paraffin-embedded tumor samples from 117 well-characterized stage I NSCLC patients and to compare the protein expression, clinical variables and survival outcome. As a micrometastatic parameter in lymph nodes (LNs), cytokeratin (CK) staining was performed.

RESULTS

The positive expression of VEGF-C and VEGF were detected in 54 (48.7%) and 86 (73.5%), respectively. We identified micrometastatic tumor cells in pathological N0 LNs in 34 (29.1%) of 117 patients. E-cadherin, alpha-catenin, beta-catenin, and gamma-catenin were identified in 70 (59.8%), 41 (35.0%), 83 (70.9%), and 61 (52.1%) specimens, respectively. The VEGF-C expression was found more frequently in squamous cell carcinoma (SQ) and in the tumors with negative expression of beta-catenin than counter features. The VEGF expression was found more frequently in the tumors with a negative expression of E-cadherin. Micrometastasis was found more frequently in a pathological T2 status and in the tumors with a negative expression of alpha-catenin. Beta-catenin and gamma-catenin expressions were found less and more frequently in SQ, respectively. A univariate and multivariate survival analysis demonstrated that old age, pathological T2 status, and micrometastasis were independently associated with an increased risk of poor survival in the patients who underwent a surgical resection of stage I NSCLC.

CONCLUSIONS

Complicated relationships exist between lymphangiogenesis/micrometastases and adhesion molecules with a specific histology. The detection of lymph nodal micrometastasis by CK may therefore be a useful marker for predicting a poor prognosis in patients who undergo a complete resection of stage I NSCLC.

Prognostic impact of fibroblast growth factor 2 in non-small cell lung cancer: coexpression with VEGFR-3 and PDGF-B predicts poor survival

PURPOSE

Fibroblast growth factor 2 (FGF2; basic fibroblast growth factor, b-FGF) and its main receptor FGFR-1 are important in both hemangiogenesis and lymphangiogenesis. Murine studies have indicated a close interplay between both FGF2 and platelet-derived growth factor-B (PDGF-B) as well as FGF2 and vascular endothelial growth factor-3 (VEGFR-3). This study investigates the prognostic impact of FGF2 and FGFR-1 in tumor cells and tumor stroma of resected non-small cell lung carcinomas (NSCLC) and explores the importance of their coexpression with VEGFR-3 or PDGF-B.

METHODS

Tumor tissue samples from 335 resected patients with stage I to IIIA NSCLC were obtained and tissue microarrays were constructed from duplicate cores of tumor cells and tumor-related stroma from each specimen. Immunohistochemistry was used to evaluate the expression of the molecular markers FGF2, FGFR-1, VEGFR-3, and PDGF-B.

RESULTS

In univariate analyses, high tumor cell FGF2 expression (p = 0.015) was a negative prognostic indicator for disease-specific survival. In tumor stroma, high FGF2 (p = 0.024) expression correlated with good prognosis. In multivariate analyses, high expression of FGF2 in tumor cells (p = 0.038) was an independent negative prognostic factor whereas increased FGF2 in stroma (p = 0.015) was a positive prognosticator. Tumor cell coexpressions of FGF2/VEGFR-3 (p < 0.001) and FGFR-1/PDGF-B (p = 0.002) were significant indicators of poor prognosis.

CONCLUSIONS

Expression of FGF2 in tumor cells is an independent negative prognostic factor, and the coexpressions of FGF2/VEGFR-3 and FGFR-1/PDGF-B are strongly associated with poor survival in NSCLC patients.

Vascular endothelial growth factor receptor-3 promotes breast cancer cell proliferation, motility and survival in vitro and tumor formation in vivo

Vascular endothelial growth factor receptor-3 is a receptor tyrosine kinase that is overexpressed in some human carcinomas, but its role in tumorigenesis has not been fully elucidated. We examined VEGFR-3 expression in normal, nonneoplastic and early stage malignant breast tissues and have shown that VEGFR-3 upregulation in breast cancer preceded tumor cell invasion, suggesting that VEGFR-3 may function as a survival signal. We characterized the biological effects of VEGFR-3 over-expression in human breast cancer cells based on two approaches: gain of function by overexpressing VEGFR-3 in MCF-7 breast cancer cells and loss of function by RNAi-mediated silencing of VEGFR-3 in MCF-7-VEGFR-3 and BT474 cells. VEGFR-3 overexpression increased cellular proliferation by 40% when MCF7-VEGFR-3 cells were compared to parental MCF7 cells, and proliferation was reduced by more than 40% when endogenous VEGFR-3 was downregulated in BT474 cells. VEGFR-3 overexpression promoted a three-fold increase in motility and invasion and both motility and invasion were inhibited by downregulation of VEGFR-3. Furthermore, VEGFR-3 overexpression promoted cellular survival under stress conditions induced by staurosporine treatment and led to anchorage-independent growth. VEGFR-3 overexpression dramatically increased tumor formation in both hormone-dependent and independent xenograft models. With estrogen stimulation, MCF7-VEGFR-3 xenografts were ten times larger than control xenografts. Finally, downregulation of VEGFR-3 expression in both xenograft model cell lines led to a significant reduction of tumor growth. For the first time, we have demonstrated that VEGFR-3 overexpression promotes breast cancer cell proliferation, motility, survival, anchorage-independent growth and tumorogenicity in the absence of ligand expression.