Resistin-like molecule ß acts as a mitogenic factor in hypoxic pulmonary hypertension via the Ca2+-dependent PI3K/Akt/mTOR and PKC/MAPK signaling pathways.

BACKGROUND: Pulmonary arterial smooth muscle cell (PASMC) proliferation plays a crucial role in hypoxia-induced pulmonary hypertension (HPH). Previous studies have found that resistin-like molecule ß (RELM-ß) is upregulated de novo in response to hypoxia in cultured human PASMCs (hPASMCs). RELM-ß has been reported to promote hPASMC proliferation and is involved in pulmonary vascular remodeling in patients with PAH. However, the expression pattern, effects, and mechanisms of action of RELM-ß in HPH remain unclear. METHODS: We assessed the expression pattern, mitogenetic effect, and mechanism of action of RELM-ß in a rat HPH model and in hPASMCs. RESULTS: Overexpression of RELM-ß caused hemodynamic changes in a rat model of HPH similar to those induced by chronic hypoxia, including increased mean right ventricular systolic pressure (mRVSP), right ventricular hypertrophy index (RVHI) and thickening of small pulmonary arterioles. Knockdown of RELM-ß partially blocked the increases in mRVSP, RVHI, and vascular remodeling induced by hypoxia. The phosphorylation levels of the PI3K, Akt, mTOR, PKC, and MAPK proteins were significantly up- or downregulated by RELM-ß gene overexpression or silencing, respectively. Recombinant RELM-ß protein increased the intracellular Ca2+ concentration in primary cultured hPASMCs and promoted hPASMC proliferation. The mitogenic effects of RELM-ß on hPASMCs and the phosphorylation of PI3K, Akt, mTOR, PKC, and MAPK were suppressed by a Ca2+ inhibitor. CONCLUSIONS: Our findings suggest that RELM-ß acts as a cytokine-like growth factor in the development of HPH and that the effects of RELM-ß are likely to be mediated by the Ca2+-dependent PI3K/Akt/mTOR and PKC/MAPK pathways.

Angiogenic potential of YKL-40 in the dynamics of tumor niche.

A multitude of clinical studies showed the elevation of YKL-40 in subjects with different kinds of tumors. It is predicted that an inherent correlation exists between survivals of cancer patients with total YKL-40 serum levels, making this factor as a potential novel biomarker. However, the crucial role of YKL-40 in the dynamics of cancers, especially angiogenesis, has not yet been completely addressed. In this review, we highlighted the various facets of YKL-40 and its importance in cancer biology as a bio-shuttle in gene therapy.

Fetal Kidney Cells Can Ameliorate Ischemic Acute Renal Failure in Rats through Their Anti-Inflammatory, Anti-Apoptotic and Anti-Oxidative Effects.

Fetal kidney cells may contain multiple populations of kidney stem cells and thus appear to be a suitable cellular therapy for the treatment of acute renal failure (ARF) but their biological characteristics and therapeutic potential have not been adequately explored. We have culture expanded fetal kidney cells derived from rat fetal kidneys, characterized them and evaluated their therapeutic effect in an ischemia reperfusion (IR) induced rat model of ARF. The fetal kidney cells grew in culture as adherent spindle shaped/polygonal cells and expressed CD29, CD44, CD73, CD90, CD105, CD24 and CD133 markers. Administration of PKH26 labeled fetal kidney cells in ARF rats resulted in a significant decrease in the levels of blood urea nitrogen, creatinine, and neutrophil gelatinase-associated lipocalin and decreased tubular necrosis in the kidney tissues (p<0.05 for all). The injected fetal kidney cells were observed to engraft around injured tubular cells, and there was increased proliferation and decreased apoptosis of tubular cells in the kidneys (p<0.05 for both). In addition, the kidney tissues of ARF rats treated with fetal kidney cells had a higher gene expression of renotropic growth factors (VEGF-A, IGF-1, BMP-7 and bFGF) and anti-inflammatory cytokine (IL10); up regulation of anti-oxidative markers (HO-1 and NQO-1); and a lower Bax/Bcl2 ratio as compared to saline treated rats (p<0.05 for all). Our data shows that culture expanded fetal kidney cells express mesenchymal and renal progenitor markers, and ameliorate ischemic ARF predominantly by their anti-apoptotic, anti-inflammatory and anti-oxidative effects.

Combined immunomodulator and antimicrobial therapy eliminates polymicrobial sepsis and modulates cytokine production in combined injured mice.

PURPOSE: A combination therapy for combined injury (CI) using a non-specific immunomodulator, synthetic trehalose dicorynomycolate and monophosphoryl lipid A (STDCM-MPL), was evaluated to augment oral antimicrobial agents, levofloxacin (LVX) and amoxicillin (AMX), to eliminate endogenous sepsis and modulate cytokine production. MATERIALS AND METHODS: Female B6D2F(1)/J mice received 9.75 Gy cobalt-60 gamma-radiation and wound. Bacteria were isolated and identified in three tissues. Incidence of bacteria and cytokines were compared between treatment groups. RESULTS: Results demonstrated that the lethal dose for 50% at 30 days (LD(50/30)) of B6D2F(1)/J mice was 9.42 Gy. Antimicrobial therapy increased survival in radiation-injured (RI) mice. Combination therapy increased survival after RI and extended survival time but did not increase survival after CI. Sepsis began five days earlier in CI mice than RI mice with Gram-negative species predominating early and Gram-positive species increasing later. LVX plus AMX eliminated sepsis in CI and RI mice. STDCM-MPL eliminated Gram-positive bacteria in CI and most RI mice but not Gram-negative. Treatments significantly modulated 12 cytokines tested, which pertain to wound healing or elimination of infection. CONCLUSIONS: Combination therapy eliminates infection and prolongs survival time but does not assure CI mouse survival, suggesting that additional treatment for proliferative-cell recovery is required.

Exogenous bFGF promotes articular cartilage repair via up-regulation of multiple growth factors.

OBJECTIVE: To investigate the roles of exogenous basic fibroblast growth factor (bFGF) on the repair of full-thickness articular cartilage defects in rabbits. DESIGN: In the present study, a double-layered collagen membrane sandwiched with bFGF-loaded-nanoparticles between a dense layer and a loose layer was implanted into full-thickness articular cartilage defects in rabbits. By grafting the membrane in a different direction, the dense layer or the loose layer facing the surface of the subchondral bone, the effects of the released bFGF on the defects and the profiles of nine growth factors (GFs) in synovial fluid (SF) were investigated using histological methods and antibody arrays, respectively. RESULTS: In the group with the loose layer facing the surface of the subchondral bone, fast release of bFGF was observed, and early high levels of endogenous transforming growth factor-ß2 (TGF-ß2), vascular endothelial growth factor (VEGF), bFGF, bone morphogenetic protein 2 (BMP-2), BMP-3, and BMP-4 in SF were detected by antibody arrays, especially on day 3. Chondrocyte-like cells were also observed in this group at an early stage. As a result, this group showed better levels of repair, as compared to the other groups in which low GF levels were detected at an early stage, and chondrocyte-like cells appeared much later. CONCLUSIONS: Our study suggests that exogenous bFGF promotes articular cartilage repair by up-regulating the levels of multiple GFs, but administration at an early stage is required.

Augmented healing of critical-size calvarial defects by baculovirus-engineered MSCs that persistently express growth factors.

Repair of large calvarial bony defects remains clinically challenging because successful spontaneous calvarial re-ossification rarely occurs. Although bone marrow-derived mesenchymal stem cells (BMSCs) genetically engineered with baculovirus (BV) for transient expression of osteogenic/angiogenic factors hold promise for bone engineering, we hypothesized that calvarial bone healing necessitates prolonged growth factor expression. Therefore, we employed a hybrid BV vector system whereby one BV expressed FLP while the other harbored the BMP2 (or VEGF) cassette flanked by Frt sequences. Transduction of rabbit BMSCs with the FLP/Frt-based BV vector led to FLP-mediated episome formation, which not only extended the BMP2/VEGF expression beyond 28 days but augmented the BMSCs osteogenesis. After allotransplantation into rabbits, X-ray, PET/CT, µCT and histological analyses demonstrated that the sustained BMP2/VEGF expression remarkably ameliorated the angiogenesis and regeneration of critical-size (8 mm) calvarial defects, when compared with the group implanted with BMSCs transiently expressing BMP2/VEGF. The prolonged expression by BMSCs accelerated the bone remodeling and regenerated the bone through the natural intramembranous pathway, filling ≈83% of the area and ≈63% of the volume in 12 weeks. These data implicated the potential of the hybrid BV vector to engineer BMSCs for sustained BMP2/VEGF expression and the repair of critical-size calvarial defects.

GGF2 (Nrg1-ß3) treatment enhances NG2+ cell response and improves functional recovery after spinal cord injury.

The adult spinal cord contains a pool of endogenous glial precursor cells, which spontaneously respond to spinal cord injury (SCI) with increased proliferation. These include oligodendrocyte precursor cells that express the NG2 proteoglycan and can differentiate into mature oligodendrocytes. Thus, a potential approach for SCI treatment is to enhance the proliferation and differentiation of these cells to yield more functional mature glia and improve remyelination of surviving axons. We previously reported that soluble glial growth factor 2 (GGF2)- and basic fibroblast growth factor 2 (FGF2)-stimulated growth of NG2(+) cells purified from injured spinal cord in primary culture. This study examines the effects of systemic administration of GGF2 and/or FGF2 after standardized contusive SCI in vivo in both rat and mouse models. In Sprague-Dawley rats, 1 week of GGF2 administration, beginning 24 h after injury, enhanced NG2(+) cell proliferation, oligodendrogenesis, chronic white matter at the injury epicenter, and recovery of hind limb function. In 2',3'-cyclic-nucleotide 3'-phosphodiesterase-enhanced green fluorescent protein mice, GGF2 treatment resulted in increased oligodendrogenesis and improved functional recovery, as well as elevated expression of the stem cell transcription factor Sox2 by oligodendrocyte lineage cells. Although oligodendrocyte number was increased chronically after SCI in GGF2-treated mice, no evidence of increased white matter was detected. However, GGF2 treatment significantly increased levels of P0 protein-containing peripheral myelin, produced by Schwann cells that infiltrate the injured spinal cord. Our results suggest that GGF2 may have therapeutic potential for SCI by enhancing endogenous recovery processes in a clinically relevant time frame.

Transcriptome analysis reveals specific changes in osteoarthritis synovial fibroblasts.

OBJECTIVE: Changes in rheumatoid arthritis synovial fibroblast (RASF) gene expression are usually defined by a comparison to osteoarthritis synovial fibroblasts (OASFs). This study was undertaken to analyse the transcriptome of OASFs as compared to RASFs and healthy synovial fibroblasts (HSFs). METHODS: The authors used microarray messenger RNA expression profiling of synovial fibroblasts cultured from osteoarthritis (OA), rheumatoid arthritis and normal synovial tissues. Quantitative real-time PCR of selected genes was performed to validate microarray data. Analysis of variance, Student t test and the Benjamini-Hochberg multiple testing correction method for multiple testing correction were used to determine the statistical significance of the changes between the three groups. RESULTS: Larger numbers of transcripts showed a differential expression in OASFs versus the other groups, rather than in RASFs versus HSFs. Cluster analysis confirmed that the differences between the three groups were mostly due to the differences between OA and the other groups. Functional classification identified a significant number of genes related to growth factor activities, cell adhesion, neurotransmission and Ras signalling that are differentially expressed in OASFs. Classical proinflammatory factors or proteases involved in cartilage degradation were not found to be overexpressed in OASFs. CONCLUSION: Cultured OASFs display a more homogeneous transcriptomic profile than RASFs when compared to HSFs. This supports the participation of synovial fibroblasts in the pathogenesis of OA and may reflect global defects in the mesenchyma-derived lineages of the different tissues in OA joints. These data support individual heterogeneity among RASFs and advise against the use of OASFs as controls.

Living cellular construct for increasing the width of keratinized gingiva: results from a randomized, within-patient, controlled trial.

BACKGROUND: The standard of care for increasing keratinized gingiva adjacent to teeth that do not require root coverage is the free gingival graft (FGG). A pilot study indicated that the use of a living cellular construct (LCC) could be effective in this clinical scenario. METHODS: A pivotal, multicenter, randomized, within-patient, controlled, open-label trial was conducted (N = 96 patients). After removing the mucosa and keratinized gingiva from the test site, either an LCC or FGG was applied. The primary efficacy endpoint was the ability of the LCC to regenerate ≥2 mm keratinized gingiva at 6 months. Secondary measures were the same color and texture as the adjacent tissue, a 1-mm width of keratinized gingiva at 6 months, patient treatment preference, surgical site sensitivity at 1 week, and patient-reported pain after 3 days. Safety was assessed by reports of adverse events. RESULTS: At 6 months, the LCC regenerated ≥2 mm of keratinized gingiva in 95.3% of patients (81 of 85 patients; P <0.001 versus a 50% predefined standard). As expected, the FGG generated more keratinized gingiva than the LCC (4.57 ± 1.0 mm versus 3.2 ± 1.1 mm, respectively). The gingiva regenerated with the LCC matched the color and texture of the adjacent gingiva. All patients achieved ≥1 mm keratinized gingiva with the LCC treatment by 6 months, and more patients preferred treatment with the LCC than with the FGG. No difference in sensitivity or pain was noted between the treatments. The treatments were well tolerated, and reported adverse events were typical for this type of periodontal surgery. CONCLUSION: The use of an LCC may provide a safe and effective therapy for augmenting the zone of keratinized gingiva.

The effect of deproteinized bovine bone on osteoblast growth factors and proinflammatory cytokine production.

OBJECTIVE: To test the ability of Bio-Oss in inducing growth factors and proinflammatory cytokines that may have a role in inflammation after grafting, bone resorption, remodeling and in the homeostasis of osteoblasts. MATERIAL AND METHODS: Normal human osteoblasts were seeded in Petri dishes containing granules of Bio-Oss, cells were harvested after confluency and RNA was extracted. Reverse transcriptase polymerase chain reaction was performed using specific primers for osteonectin, bone sialoprotein (BSP), bone morphogenetic protein (BMP)-2 and BMP-7, platelet-derived growth factor (PDGF), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha) and integrin beta1. Glycerol-3-phosphate dehydrogenase was used as the housekeeping gene and normal human osteoblasts grown on Petri dishes without Bio-Oss granules were used as negative controls. RESULTS: Osteoblast grown on Bio-Oss showed a normal RNA expression of osteonectin, integrin beta1 and PDGF. However, compared with control osteoblasts it showed a reduced expression of BSP, BMP-2 and BMP-7, IL-6 and TNF-alpha. CONCLUSIONS: Our findings further support the evidence that Bio-Oss is an excellent biomaterial that does not enhance the production of proinflammatory cytokines.

Growth factors and gene expression of stem cells: bone marrow compared with peripheral blood.

PURPOSE: To evaluate and compare the presence of cytokines and growth factors in both bone marrow (BM) and peripheral blood. MATERIAL: Samples of autogenous BM aspirate and peripheral blood (PB) from 7 patients ranging in age from 49 to 80 years were analyzed with real-time polymerase chain reaction technology to identify and compare selected gene expression for specific cytokines and growth factors. The genes selected for analysis included those involved in osteogenesis, hematogenesis, angiogenesis, extracellular matrix molecules, and cell-adhesion molecules. A maximum of 4 cc';s BM aspirate was taken from the anterior iliac crest and 0.5 mL of venous blood was drawn from each of 7 patients. RESULTS: The results of the analysis indicate that both circulating blood and BM aspirate contain large quantities of a host of growth factors and cytokines. More platelet-derived growth factor is expressed in patient blood (PB) than in BM. Vascular endothelial growth factor alpha is expressed slightly greater in BM and vascular endothelial growth factor beta is slightly more prominent in PB. Transforming growth factors (TGFs) TGFA, TGFB1, and TGFB3 were equally expressed in BM and PB, and TGFB2 had a greater expression in PB. Bone morphogenetic proteins (BMPs) 1, 3, 7, 8B, R1A, and PR2 were almost equally expressed in BM and PB. BMPs 4 and 6 were expressed greater in PB. BMP2 was expressed more in BM. Extracellular matrix factors were equally expressed in PB and BM. Mesenchymal stem cell lineage markers varied in PB and BMA, and hematopoietic stem cell lineage markers were expressed more in PB than BM. Gene expression for angiogenic factors were equally expressed in PB and BM. CONCLUSION: In this investigation, specific cytokines and growth factors in BM are compared with those in peripheral blood. Each has similar biologic effects and most expressed equally in BM and PB. However, BMP2 and vascular endothelial growth factor alpha had greater expression in BM.

Emdogain in carcinogenesis: a systematic review of in vitro studies.

Emdogain is a commercial product of unknown composition and is clinically used to induce periodontal regeneration. This study aims to review current knowledge of the in vitro effects of Emdogain on oral tissues and, in particular, factors related to carcinoma. A systematic approach was used to review studies from the Embase and Pubmed databases; a total of 76 studies were included. These comprised in vitro studies of the cytokines in, or regulated by, Emdogain and assays designed to study the effects of EMD on human cells in oral tissues or malignant cells. Several studies have shown that EMD regulates the proliferation, migration, adhesion, gene expression, and cytokine production of (pre-)osteoblasts, periodontal fibroblasts, and gingival fibroblasts. However, the effects of EMD on malignant oral cells are not well understood. EMD seems to have broad regulatory effects on malignant cells and on several carcinoma-related factors. Evidence suggests that patients with premalignant or malignant mucosal lesions should not be treated with EMD.

Microarray evaluation of age-related changes in human dental pulp.

INTRODUCTION: The dental pulp undergoes age-related changes that could be ascribed to physiological, defensive, or pathological irritant-induced changes. These changes are regulated by pulp cell activity and by a variety of extracellular matrix (ECM) macromolecules, playing important roles in growth regulation, tissue differentiation and organization, formation of calcified tissue, and defense mechanisms and reactions to inflammatory stimuli. The aim of this research was to better understand the genetic changes that underlie the histological modification of the dental pulp in aging. METHODS: The gene expression profile of the human dental pulp in young and older subjects was compared by RNA microarray analysis that allowed to simultaneously analyze the expression levels of thousands of genes. Data were statistically analyzed by Significance Analysis of Microarrays (SAM) Ingenuity Pathway Analysis (IPA) software. Semiquantitative and real-time reverse-transcriptase polymerase chain reaction analyses were performed to confirm the results. RESULTS: Microarray analysis revealed several differentially expressed genes that were categorized in growth factors, transcription regulators, apoptosis regulators, and genes of the ECM. The comparison analysis showed a high expression level of the biological functions of cell and tissue differentiation, development, and proliferation and of the immune, lymphatic, and hematologic system in young dental pulp, whereas the pathway of apoptosis was highly expressed in older dental pulp. CONCLUSIONS: Expression profile analyses of human dental pulp represent a sensible and useful tool for the study of mechanisms involved in differentiation, growth and aging of human dental pulp in physiological and pathological conditions.

Neuropeptides regulate expression of angiogenic growth factors in human dental pulp fibroblasts.

INTRODUCTION: Neuropeptides play an important role in inflammation and repair and have been implicated in mediating angiogenesis. Pulp fibroblasts express neuropeptide receptors, and the aim of this research was to investigate whether neuropeptides could regulate angiogenic growth factor expression in vitro METHODS: An angiogenic array was used to determine the levels of 10 angiogenic growth factors expressed by human pulp fibroblasts. RESULTS: Pulp fibroblasts were shown to express angiogenin, angiopoietin-2, epidermal growth factor, basic fibroblast growth factor, heparin-binding epidermal growth factor, hepatocyte growth factor, leptin, platelet-derived growth factor, placental growth factor, and vascular endothelial growth factor. Furthermore, the neuropeptides substance P, calcitonin gene-related peptide, vasoactive intestinal polypeptide, and neuropeptide Y altered angiogenic growth factor expression in vitro. CONCLUSIONS: The regulation of angiogenic growth factor expression by neuropeptides suggests a novel role for neuropeptides in pulpal inflammation and repair.

Isolation and characterization of brassinosteroids from algal cultures of Chlorella vulgaris Beijerinck (Trebouxiophyceae).

The brassinosteroids (BRs) occur ubiquitously in the plant kingdom. The occurrence of BRs has been demonstrated in almost every part of higher plants, such as pollen, flower buds, fruits, seeds, vascular cambium, leaves, shoots and roots. In this study, BRs were isolated and identified in the culture of wild-type Chlorella vulgaris. Seven BRs, including teasterone, typhasterol, 6-deoxoteasterone, 6-deoxotyphasterol, 6-deoxocastasterone, castasterone and brassinolide, were identified by GC-MS. All compounds belong to the BR biosynthetic pathway. The results suggest that early and late C6 oxidation pathways are operating in C. vulgaris. This study represents the first isolation of BRs from C. vulgaris cultures.

Suppression of neuroblastoma growth by dipeptidyl peptidase IV: relevance of chemokine regulation and caspase activation.

Imbalanced protease expression and activities may contribute to the development of cancers, including neuroblastoma (NB). NB is a fatal childhood cancer of the sympathetic nervous system that frequently overexpresses mitogenic peptides, chemokines and their receptors. Dipeptidyl peptidase IV (DPPIV), a cell surface serine protease, inactivates or degrades some of these bioactive peptides and chemokines, thereby regulating cell proliferation and survival. Our studies show that DPPIV is expressed in normal neural crest-derived structures, including superior cervical and dorsal root ganglion cells, sciatic nerve, and in adrenal glands, but its expression is greatly decreased or lost in cells derived from NB, their malignant counterpart. Restoration of DPPIV expression in NB cells led to their differentiation in association with increased expression of the neural marker MAP2 and decreased expression of chemokines, including stromal-derived factor 1 (SDF1) and its receptor CXCR4. Furthermore, DPPIV promoted apoptosis, and inhibited SDF1-mediated in vitro cell migration and angiogenic potential. These changes were accompanied by caspase activation and decreased levels of phospho-Akt and MMP9 activity, which are downstream effectors of SDF1-CXCR4 signaling. Importantly, DPPIV suppressed the tumorigenic potential of NB cells in a xenotransplantation mouse model. These data support a potential role for DPPIV in inhibiting NB growth and progression.

Effects of provisional acrylic resins on gingival fibroblast cytokine/growth factor expression.

STATEMENT OF PROBLEM: Several studies have reported that polymerized resin materials may release agents into surrounding tissues. These agents could alter cytokine/growth factor expression. PURPOSE: The purpose of this study was to determine the effects that provisional acrylic resins have on cell toxicity and the expression of cytokines/growth factors from human gingival fibroblasts (HGFs). MATERIAL AND METHODS: The materials used in this study were chemically activated bis-acryl composite (Chem-Bis), chemically activated polyethyl methacrylate (Chem-PEMA), chemically activated polymethyl methacrylate (Chem-PMMA), and heat-activated polymethyl methacrylate (Heat-PMMA) resins. HGFs were incubated for 72 hours in the presence of eluate from each resin and in the absence of any eluate (negative control). The conditioned media were then collected and stored at -70 degrees C. Cell toxicity was determined using a lactate dehydrogenase method. Cytokine/growth factor expression was examined using cytokine antibody arrays. The experiments were repeated 3 times. The data were analyzed with 1-way ANOVA, Mann-Whitney test, and 1-sample t test (alpha=.05). RESULTS: There was no significant cell toxicity observed from the eluates. The cytokine/growth factor expression induced by Chem-Bis was significantly greater than the control for growth-regulated oncogene (GRO) (P<.001), monocyte chemoattractant protein-1 (MCP-1) (P=.031), and tumor necrosis factor-beta (TNF)-beta (P=.009). For Chem-PEMA, the cytokine/growth factor expression was significantly greater than the control for GRO-alpha (P=.022), interleukin (IL)-13 (P=.031), and TNF-alpha (P=.017). The cytokines/growth factors induced by Chem-PEMA were significantly less than the control (P=.008) and Chem-Bis for IL-8 (P=.042). The expression induced by Chem-PMMA was significantly greater than the control for IL-13 (P=.036), IL-1 alpha (P=.003), IL-2 (P=.020), and IL-5 (P=.045). Finally, Heat-PMMA induced significantly greater levels than the control for GRO (P<.001) and IL-13 (P=.008). CONCLUSIONS: This study demonstrated that the resins evaluated were nontoxic to the HGFs. There were changes in the cytokine/growth factor levels that were statistically significant, but may not be clinically significant.

Chemotherapeutic drugs and human tumor cells cytokine network.

The ability of human tumor cell lines to produce various cytokines, chemokines, angiogenic and growth factors was investigated using Luminex multiplex technology. Media conditioned by tumor cells protected tumor cells from drug-induced apoptosis and stimulated tumor cell proliferation. Antibodies neutralizing IL-6, CXCL8, CCL2 and CCL5 blocked this stimulation. Treatment of tumor cells with doxorubicin and cisplatin resulted in a substantial increase in the production of IL-6, CXCL8, CCL2, CCL5, BFGF, G-CSF and VEGF. This stimulation was associated with drug-induced activation of NF-kappaB, AP-1, AP-2, CREB, HIF-1, STAT-1, STAT-3, STAT-5 and ATF-2 transcription factors and upregulation of IL-6, CXCL8, FGF-2, CSF-3 and CCL5 gene expression. Treatment of tumor cells with doxorubicin and antibodies neutralizing G-CSF, CCL2 or CCL5 had higher inhibitory effects than each modality used alone. These results indicate that chemokines and growth factors produced by tumor by binding to the cognate receptors on tumor and stroma cells could provide proliferative and antiapoptotic signals helping tumor to escape drug-mediated destruction. Clinical studies showed that antibodies neutralizing VEGF (Avastin/Bevacizumab) or blocking HER2/neu signaling (Herceptin/Trastuzumab) could increase the efficacy of chemotherapy, although these beneficial effects have been limited. It is possible that drug-stimulated production of growth and proangiogenic factors could counterbalance the effects of antibody therapy. In addition, numerous growth factors and chemokines share angiogenic and growth-stimulating properties, and thus reduction of a single factor is insufficient to completely block tumor growth. Thus, a broad disruption of tumor cytokine network is needed to further increase the efficacy of cancer therapy.