Ang Yuan

p53 controls cancer cell invasion by inducing the MDM2-mediated degradation of Slug

The tumour suppressor p53 is known to prevent cancer progression by inhibiting proliferation and inducing apoptosis of tumour cells. Slug, an invasion promoter, exerts its effects by repressing E-cadherin transcription. Here we show that wild-type p53 (wtp53) suppresses cancer invasion by inducing Slug degradation, whereas mutant p53 may stabilize Slug protein. In non-small-cell lung cancer (NSCLC), mutation of p53 correlates with low MDM2, high Slug and low E-cadherin expression. This expression profile is associated with poor overall survival and short metastasis-free survival in patients with NSCLC. wtp53 upregulates MDM2 and forms a wtp53–MDM2–Slug complex that facilitates MDM2-mediated Slug degradation. Downregulation of Slug by wtp53 or MDM2 enhances E-cadherin expression and represses cancer cell invasiveness. In contrast, mutant p53 inactivates Slug degradation and leads to Slug accumulation and increased cancer cell invasiveness. Our findings indicate that wtp53 and p53 mutants may differentially control cancer invasion and metastasis through the p53–MDM2–Slug pathway.

Vascular Endothelial Growth Factor 189 mRNA Isoform Expression Specifically Correlates With Tumor Angiogenesis, Patient Survival, and Postoperative Relapse in Non–Small-Cell Lung Cancer

PURPOSE The purpose of this study was to evaluate the correlation between the expression of four different vascular endothelial growth factor (VEGF) mRNA isoforms (VEGF121, VEGF165, VEGF 189, and VEGF206) and the clinicopathologic characteristics, tumor angiogenesis, and outcome of patients with non-small-cell lung cancer. PATIENTS AND METHODS We examined the expression of four different VEGF mRNA isoforms in 57 non-small-cell lung cancers using reverse transcriptase polymerase chain reaction and the tumor angiogenesis using immunohistochemical staining. RESULTS All 57 lung cancer samples expressed the VEGF121, VEGF165, and VEGF189 mRNA isoforms, and three expressed the VEGF206 mRNA isoform. A high tumoral VEGF189 mRNA isoform expression ratio was associated with a high intratumoral microvessel count (P = .013), short survival (< 24 months; P = .001), and early postoperative relapse (< 12 months; P = .001). Survival and postoperative relapse time were significantly shorter in patients with a high compared with a low tumor VEGF189 mRNA isoform expression ratio (P = .0001 and P = .0086, respectively, log-rank test). In contrast, the VEGF165 and VEGF 206 mRNA isoform expression ratios showed no statistical correlation with tumor angiogenesis, postoperative relapse time, or survival. A high VEGF121 mRNA isoform expression ratio was associated with short survival (< 24 months) and early relapse (< 12 months). Multivariate analysis showed that VEGF 189 mRNA isoform expression, microvessel count, and nodal status were the most important independent prognostic factors for patient survival and postoperation recurrence. CONCLUSION The VEGF189 mRNA isoform expression ratio shows a greater correlation with tumor angiogenesis, postoperative relapse time, and survival than do the expression ratios for the VEGF121, VEGF165, and VEGF206 mRNA isoforms and can be used as a prognostic indicator for patients with non-small-cell lung cancers.

The role of interleukin-8 in cancer cells and microenvironment interaction.

Abstract Interleukin (IL)-8, a cytokine of the CXC chemokine family that was originally classified as a neutrophil chemoattractant, is now reported to play an important role in tumor progression and metastasis in a variety of human cancers, including lung cancers. IL-8 biologic activity in tumors and the tumor microenvironment may contribute to tumor progression through its potential function in the regulation of angiogenesis, cancer cell growth and survival, tumor cell motion, leukocyte infiltration and modification of immune responses. Recently, infiltrating macrophages in tumor stroma have been considered to be able to stimulate cancer growth, enhance angiogenesis and promote metastasis, and has prognostic significance in several human cancers. Accumulating evidence also shows that cancer cells and stromal cell interaction can stimulate cancer cells, as well as stromal cells in the expression of IL-8 and other growth factors. Here, we summarize current information about IL-8 biology in human lung cancers and focus on its effect on tumor angiogenesis, regulation of IL-8 expression in tumors, its prognostic significances, the role of tumor infiltrating macrophages in the production of IL-8 in cancer cells and the tumor microenvironment, gene expression profiles after cancer cell-stromal cell interaction, and the effect of a variety anti- inflammatory drugs on the modification of IL-8 and other gene expressions in cancer cells and the tumor microenvironment in lung cancers.

Correlation of total VEGF mRNA and protein expression with histologic type, tumor angiogenesis, patient survival and timing of relapse in non‐small‐cell lung cancer

We have quantified the expression of all 4 isoforms of vascular endothelial growth factor (VEGF) mRNA in non‐small‐cell lung cancer (NSCLC) using a new kinetic quantitative PCR method, real‐time quantitative (RTQ) RT‐PCR, and investigated the association between VEGF expression at the mRNA and protein levels and the clinicopathologic variables, tumor angiogenesis, patient survival and timing of relapse. Surgical tumor specimens from 72 NCSLC patients (37 squamous‐cell carcinomas, 35 adenocarcinomas) were examined. Twenty‐eight patients had stage I, 10 stage II and 34 stage IIIA or IIIB disease. Total VEGF mRNA (all 4 isoforms) was quantified by RTQ RT‐PCR, while VEGF protein expression and microvessel number in tumors were assessed immunohistochemically. VEGF mRNA was detected in all 72 tumor samples at significantly higher levels than in adjacent normal tissue. Tumoral VEGF mRNA levels correlated strongly with the VEGF protein staining score and microvessel count. Adenocarcinomas showed significantly higher VEGF mRNA expression and a higher protein staining score than squamous‐cell carcinomas. High tumoral VEGF mRNA expression was associated with advanced (IIIA or IIIB) tumor stage, lymph node metastasis, high tumoral microvessel counts, short patient survival (<24 months) and early relapse (<12 months), while a high VEGF protein staining score was associated with high tumoral microvessel counts, short patient survival and early relapse. Patients with high tumoral levels of both VEGF mRNA and protein had significantly shorter survival and earlier relapse. In multivariate analysis, the VEGF protein staining score and nodal status were the most important independent predictors of survival and recurrence. We conclude that RTQ RT‐PCR is a sensitive method for detecting and quantifying VEGF mRNA expression in NSCLC and that the expression levels of total VEGF mRNA and protein in NSCLC are strongly associated with histologic type, tumor angiogenesis, survival and timing of relapse. High VEGF expression in adenocarcinomas may contribute to their greater metastatic potential. Int. J. Cancer 89:475–483, 2000.

Targeting Neuropilin 1 as an Antitumor Strategy in Lung Cancer

Purpose: Neuropilin 1 (NRP1) is a mediator of lung branching and angiogenesis in embryonic development and angiogenesis in cancer. The role of NRP1 in cancer progression is not fully elucidated. We investigated the role of NRP1 in cancer invasion and tumor angiogenesis, its signaling pathways, prognostic significance, and therapeutic implications. Experimental Design: Sixty patients with non–small cell lung cancer (NSCLC) were studied. NRP1 mRNA expression was measured using real-time quantitative reverse-transcription PCR. NRP1 and cancer cell invasion, angiogenesis, and signaling pathways were studied using NRP1 stimulation by vascular endothelial growth factor 165 (VEGF165) and NRP1 inhibition by small interfering RNAs (siRNA), soluble NRP1 (sNRP1), and NRP1-inhibition peptides. The NRP1-inhibition peptides were identified using a phage display peptide library. Results: NSCLC patients with high expression of NRP1 had shorter disease-free (P = 0.0162) and overall survival (P = 0.0164; log-rank test). Multivariate analyses showed NRP1 is an independent prognostic factor in overall (HR, 2.37, 95% CI = 1.15 to 4.9, P = 0.0196) and disease-free survival [hazard ratio (HR), 2.38; 95% confidence interval (95% CI), 1.15-4.91; P = 0.0195] of NSCLC patients. Knockdown of NRP1 suppressed cancer cell migration, invasion, filopodia formation, tumorigenesis, angiogenesis, and in vivo metastasis. NRP1 signaling pathways involved VEGF receptor 2 and phosphoinositide-3-kinase (PI3K) and Akt activation. Two potent synthetic anti-NRP1 peptides, DG1 and DG2, which block NRP1 signaling pathways and suppress tumorigenesis, cancer invasion, and angiogenesis, were identified. Conclusions: NRP1 is a cancer invasion and angiogenesis enhancer. NRP1 expression is an independent predictor of cancer relapse and poor survival in NSCLC patients. NRP1 plays a critical role in tumorigenesis, cancer invasion, and angiogenesis through VEGF, PI3K, and Akt pathways. NRP1 may have potential as a new therapeutic target in NSCLC.

Cardiac troponin I levels are a risk factor for mortality and multiple organ failure in noncardiac critically ill patients and have an additive effect to the APACHE II score in outcome prediction.

Cardiac troponin I (cTnI) is a specific marker of myocardial damage used in the diagnosis of acute coronary syndrome (ACS). Recent studies have shown that cTnI levels can also be elevated in patients without ACS, such as in sepsis and trauma patients, and that this is associated with an adverse prognosis. We have evaluated the clinical implications and prognostic significance of serum cTnI levels in noncardiac critically ill patients in a prospective observational study in a general medical intensive care unit at a tertiary-level hospital. A total of 108 consecutive patients without ACS or other cardiac disease was enrolled. Serum cTnI levels were measured on admission using enzyme-linked immunoabsorbant assay kits. Clinical laboratory parameters and outcome were compared between patients with elevated and normal cTnI levels. The prognostic significance of cTnI levels and the Acute Physiology And Chronic Health Evaluation (APACHE) II score was also analyzed. Forty-nine patients (45%) had elevated cTnI levels and 59 (55%) had normal levels. Compared with patients with normal cTnI levels, patients with elevated levels had a higher incidence of new failure of two or more organs, had a lower left ventricular ejection fraction during admission, were more likely to be associated with bacteremia, and had a higher intensive care unit mortality; they also had a significantly shorter survival over a 180-day follow up, before and after stratification by the APACHE II score. Multiple organ failure was the leading cause of mortality in patients with elevated cTnI levels. By multivariate analysis, elevated cTnI levels, a high APACHE II score, and underlying cancer were the three most important independent predictors for a shorter survival. Combination analysis showed a shorter survival in patients with a high APACHE II score plus elevated cTnI levels than in patients with a high APACHE II score or elevated cTnI levels alone. In conclusion, elevated serum cTnI levels is a risk factor for multiple organ failure and mortality in noncardiac critically ill patients, and the cTnI levels and APACHE II score have an additive effect in outcome prediction.

Total cyclooxygenase‐2 mRNA levels correlate with vascular endothelial growth factor mRNA levels, tumor angiogenesis and prognosis in non‐small cell lung cancer patients

Interaction between cancer cells and adjacent stromal cells is important to promote tumor development. Our aim was to study total COX‐2 mRNA expression in both cancer cells and surrounding stromal cells and its association with angiogenic factor VEGF mRNA expression, tumor angiogenesis and prognosis in patients with NSCLC. COX‐2 mRNA expression in both cancer cells and stromal tissue was analyzed using real‐time quantitative (RTQ) RT‐PCR in 60 NSCLC surgical specimens. Immunohistochemistry (IHC) was used to localize COX‐2 protein in tumor specimens. Correlations between tumoral total COX‐2 mRNA expression and VEGF mRNA expression (measured by RTQ RT‐PCR), intratumoral microvessel counts (evaluated by IHC), other clinicopathologic variables, survival and relapse were tested. COX‐2 protein expression was found in cancer as well as the surrounding stromal cells (including infiltrating inflammatory cells and endothelial cells of tumor‐associated microvessels). VEGF protein expression was mainly located in cancer cells. There was a significant association between high tumoral total COX‐2 mRNA expression and high VEGF mRNA expression (p = 0.01) or high intratumoral MVC (p < 0.001) but not other clinicopathologic variables, including tumor status and lymph node metastasis. Patients with higher tumoral total COX‐2 mRNA expression had a statistically shorter survival time (median 15.0 ± 2.61 months) and relapse time (median 5.0 ± 1.37 months) than those with lower tumoral total COX‐2 mRNA expression (median 40.0 ± 3.12 and 34.0 ± 3.11 months; p < 0.0001 and p < 0.0001, respectively, log‐rank test). A significant difference in survival and relapse time was also seen between patients with high and low tumoral VEGF mRNA expression and between those with high and low intratumoral MVC (p = 0.0046 and p = 0.0038, respectively). After stratification by disease stage or histologic subtype, the prognostic significance of high total COX‐2 mRNA expression was still apparent in both stage I and stage II–IV and in both squamous cell carcinoma and adenocarcinoma (p ≤ 0.01 for all). Multivariate analysis using the Cox regression model with backward elimination showed that tumoral total COX‐2 mRNA expression and lymph node status were the 2 most important independent prognostic predictors for survival and disease relapse. We report that total COX‐2 mRNA expression in cancer cells and surrounding stromal cells correlates strongly and positively with VEGF mRNA expression, intratumoral MVC and adverse prognosis in NSCLC patients. This implies that COX‐2 expression in both cancer cells and stromal cells within the tumor microenvironment may play an important role in upregulating the expression of the angiogenic factor VEGF and tumor angiogenesis in NSCLC and explains, in part, the adverse prognostic effect of COX‐2 overexpression in patients with NSCLC.

Tumor-Associated Macrophage: Its Role in Cancer Invasion and Metastasis

Cancer metastasis is not exclusively regulated by the deregulation of metastasis-promoting or suppressing genes in cancer cells. The interaction between cancer cells and the stromal cells has been shown recently to promote cancer metastasis. The macrophages within the tumor, referring to as tumour-associated macrophages (TAMs), are the pivotal member of stromal cells. TAMs are derived from peripheral blood monocytes recruited into the tumor. Upon activated by cancer cells, the TAMs can release a vast diversity of growth factors, proteolytic enzymes, cytokines, and inflammatory mediators. Many of these factors are key agents in cancer metastasis. The presence of extensive TAM infiltration has been shown to correlate with cancer metastasis and poor prognosis in a variety of human carcinomas. TAMs promote cancer metastasis through several mechanisms including tumor angiogenesis, tumor growth, and tumor cell migration and invasion. There are complex paracrine-signaling networks between TAMs and cancer cells to activate each other. The colony-stimulating factor 1/epidermal growth factor paracrine loop is well known in regulation of breast cancer cells invasion. TAMs-derived proteases, such as matrix metalloproteinases, urokinase-type plasminogen activator, and cathepsin B can promote cancer cells metastasis. The roles of TAMs in epidermal-mesenchymal transition of cancer cells and resistance to cancer treatment are novel fields of study. On the other hand, some investigations showed that the TAMs may play an important role in anti-tumor activity. The control of TAMs to be pro-metastatic or tumoricidal is an important subject for cancer therapy.

Clinical and Microbiological Characteristics of Rhizobium radiobacter Infections

Data obtained from 1996 to 2002 on 13 patients with Rhizobium radiobacter infections were analyzed. Ten patients (76%) had underlying hematological malignancy or solid-organ cancer. Six patients (46%) had febrile neutropenia during the course of R. radiobacter infection. The majority (54%) of infections were catheter-related bacteremia, and 92% of infections were hospital acquired. All the patients survived. Eighteen isolates were recovered from the 13 patients, and each isolate was susceptible to cefepime, piperacillin-tazobactam, carbapenems, and ciprofloxacin. The pulsed-field gel electrophoresis profiles differed among the isolates recovered from different patients, indicating the absence of nosocomial spread of the organism.

Opposite Effects of M1 and M2 Macrophage Subtypes on Lung Cancer Progression.

Macrophages in a tumor microenvironment have been characterized as M1- and M2-polarized subtypes. Here, we discovered the different macrophages’ impacts on lung cancer cell A549. The M2a/M2c subtypes promoted A549 invasion and xenograft tumor growth. The M1 subtype suppressed angiogenesis. M1 enhanced the sensitivity of A549 to cisplatin and decreased the tube formation activity and cell viability of A549 cells by inducing apoptosis and senescence. Different macrophage subtypes regulated genes involved in the immune response, cytoskeletal remodeling, coagulation, cell adhesion, and apoptosis pathways in A549 cells, which was a pattern that correlated with the altered behaviors of the A549 cells. Furthermore, we found that the identified M1/M2 gene signatures were significantly correlated with the extended overall survival of lung cancer patients. These results suggest that M1/M2 gene expression signature may be used as a prognostic indicator for lung cancer patients, and M1/M2 polarization may be a target of investigation of immune-modulating therapies for lung cancer in the future.