Stimulatory effects of EGF and TGF-alpha on invasive activity and 5'-deoxy-5-fluorouridine sensitivity in uterine cervical-carcinoma SKG-IIIb cells

Matrix metalloproteinase-9 and cell division in neuroblastoma cells and bone marrow macrophages

Matrix metalloproteinases (MMPs) degrade the extracellular matrix and carry out key functions in cell development, cancer, injury, and regeneration. In addition to its well recognized extracellular action, functional intracellular MMP activity under certain conditions is supported by increasing evidence. In this study, we observed higher gelatinase activity by in situ zymography and increased MMP-9 immunoreactivity in human neuroblastoma cells and in bone marrow macrophages undergoing mitosis compared with resting cells. We studied the pattern of immunoreactivity at the different stages of cell division by confocal microscopy. Immunostaining with different monoclonal antibodies against MMP-9 revealed a precise, dynamic, and well orchestrated localization of MMP-9 at the different stages of cell division. The cellular distribution of MMP-9 staining was studied in relation to that of microtubules. The spatial pattern of MMP-9 immunoreactivity suggested some participation in both the reorganization of the nuclear content and the process of chromatid segmentation. We then used several MMP-9 inhibitors to find out whether MMP-9 might be involved in the cell cycle. These drugs impaired the entry of cells into mitosis, as revealed by flow cytometry, and reduced cell culture growth. In addition, the silencing of MMP-9 expression with small interfering RNA also reduced cell growth. Taken together, these results suggest that intracellular MMP-9 is involved in the process of cell division in neuroblastoma cells and in primary cultures of macrophages.

Epidermal growth factor 61 A/G polymorphism and uterine cervical cancer

Cervical cancer, the second most common malignancy in women worldwide, is almost invariably associated with infection by human papillomavirus (HPV). However, although many women are infected with high-risk types of HPV, only a subset of infected women will ever develop cervical cancer. Therefore, host genetic factor may play a role in cervical carcinogenesis. Alterations in epidermal growth factor receptor (EGFR) are common events in cervical cancer. Therefore, we hypothesized that a functional polymorphism in the 5′ untranslated region of the epidermal growth factor (EGF) gene, a natural ligand of the EGFR, may play a role in the cervical carcinogenesis and tumor invasiveness. We assessed the possible association between EGF +61 A/G polymorphism and cervical cancer risk in a hospital-based case–control study among 337 Korean women (168 cases, 169 age-matched controls). The frequencies of EGF +61 allele and genotype were not different between cases and controls. We observed increasing trend of lymph node metastasis from A/A homozygous genotype toward G/G homozygous genotype. We did not find any evidence that EGF +61 A/G polymorphism was associated with individual susceptibility of cervical cancer. However, although it was not statistically significant, the increasing trend of lymph node metastasis according to EGF genotype suggests the possibility that individual variance of EGF expression may be associated with cervical cancer invasiveness. We also confirmed that there exists striking ethnic heterogeneity of EGF genotype between Caucasian and East Asian population

Expression of Membrane Type 1 Matrix Metalloproteinase Is Associated with Cervical Carcinoma Progression and Invasion

Membrane type 1 matrix metalloproteinase (MT1-MMP) is frequently expressed by cancer cells and is believed to play an important role in cancer cell invasion and metastasis. However, little is known about the role of MT1-MMP in mediating invasiveness of cervical cancer cells. In this study, we examined MT1-MMP expression in 58 primary human cervical tissue specimens, including normal cervix, low-grade squamous intraepithelial lesions (LSIL), high-grade SILs (HSIL), and invasive carcinomas. We also evaluated MT1-MMP, MMP-2, and tissue inhibitor of metalloproteinase-2 expression in several cervical cancer-derived cell lines, human papillomavirus (HPV)-immortalized keratinocytes, and keratinocytes derived from a LSIL. Using in situ hybridization techniques to study the cervical tissue specimens, we found that MT1-MMP expression increases with cervical tumor progression (Spearman correlation coefficient = 0.66; P < 0.0001, exact test). Specifically, MT1-MMP expression is very low or absent in normal cervix and LSILs, is readily detectable in HSILs, and is very strongly expressed in nearly all invasive carcinomas. Most but not all cervical cancer-derived cell lines also expressed significant levels of MT1-MMP and MMP-2. Constitutive expression of exogenous MT1-MMP in cervical carcinoma-derived cells and HPV-immortalized keratinocytes with low endogenous levels of MT1-MMP induced invasiveness in collagen I, but this effect was not observed in LSIL-derived keratinocytes. Our results show that MT1-MMP is a key enzyme mediating cervical cancer progression. However, MT1-MMP alone is not always sufficient for inducing keratinocyte invasiveness at least in the collagen I invasion assay used in this study. Further studies of gene expression in preinvasive and invasive cervical cancers should assist with identification of additional critical factors mediating cervical cancer progression.

Vascular Endothelial Growth Factor-C Expression and Invasive Phenotype in Ovarian Carcinomas

PURPOSE

To investigate the biological correlation between vascular endothelial growth factor (VEGF)-C expression and invasive phenotype in ovarian carcinomas.

EXPERIMENTAL DESIGN

Gene and protein expression levels of VEGF-C in 10 ovarian carcinoma cell lines were correlated with invasive activity of the cells. The correlation between immunohistochemical expression of VEGF-C and tumor aggressiveness in 73 ovarian carcinomas was also examined with respect to clinicopathologic features and patient outcome.

RESULTS

VEGF-C gene and protein expression differed remarkably among the cell lines, and there was a statistical correlation among VEGF-C expression, in vitro invasive activity, and matrix metalloproteinase-2 (MMP-2) gene expression and its activity. Anti-VEGF-C and anti-MMP-2 antibodies inhibited the invasive activity of tumor cells. VEGF-C expression in clinical tissue samples was well correlated with clinical stages, retroperitoneal lymph node metastasis, MMP-2 expression, angiogenesis, lymphangiogenesis, and low apoptotic index (AI). The patients whose tumors had strong VEGF-C expression and low AI underwent a poorer prognosis than did those with weak VEGF-C expression and high AI.

CONCLUSION

VEGF-C expression is closely related to invasive phenotype and affects the patient's survival in ovarian carcinomas.

Effect of 5-fluorouracil and epidermal growth factor on cell growth and dihydropyrimidine dehydrogenase regulation in human uterine cervical carcinoma SKG-IIIb cells

We previously demonstrated that epidermal growth factor (EGF) induces a decrease in dihydropyrimidine dehydrogenase (DPD), which is the first and rate-limiting enzyme in the catabolism of 5-fluorouracil (5-FU), in EGF receptor (EGFR)-positive human SKG-IIIb uterine cervical carcinoma cells, and thereby increased the sensitivity of the cells to 5-FU. In the present study, we examined the individual and combined effects of 5-FU and EGF on growth and DPD activity in SKG-IIIb cells, and also investigated the mode of regulation of DPD activity. The cells showed sensitivity to 5-FU, and growth was stimulated by EGF. When the agents were used in combination, the sensitivity of SKG-IIIb cells to 5-FU was increased roughly sixfold at maximum, as judged in terms of the 50% growth-inhibitory concentration. We then examined the effects of 5-FU and EGF on DPD. Either agent inhibited DPD activity and protein expression in a concentration-dependent manner. Expression of DPD mRNA was concentration-dependently inhibited by treatment with 5-FU and by EGF at a concentration that strongly stimulated cell growth. Further, combination treatment inhibited DPD activity, as well as DPD protein and mRNA expression, more strongly than did treatment with 5-FU or EGF alone. These results suggest that inhibition of DPD activity by EGF or 5-FU is regulated at least at the level of protein expression and that regulation via mRNA is also involved. The above findings indicate that 5-FU and EGF act synergistically in suppressing DPD activity and that the use of 5-FU against tumors in which EGF plays an important role would maximize the potential of 5-FU as an anticancer drug.

Correlation between vascular endothelial growth factor-C expression and invasion phenotype in cervical carcinomas

The correlation between vascular endothelial growth factor (VEGF)-C gene expression and in vitro invasive activity and matrix metalloproteinase (MMP)-2 or 9 gene expression and proteolytic activity in 11 cervical carcinoma cell lines, was investigated. Immunohistochemical expression of VEGF-C in 52 cervical carcinoma tissues was also correlated with tumor aggressiveness with respect to clinicopathologic features, tumor vascularity, MMP-2 expression and patient outcome. Expression of VEGF-C mRNA differed remarkably among the cell lines and there was a statistical correlation between VEGF-C gene expression and the number of invaded tumor cells (p = 0.0009) and MMP-2 gene expression and activity (p < 0.05). Anti-VEGF-C antibody inhibited the invasive and proteolytic activity of tumor cells in a concentration-dependent manner. VEGF-C or MMP-2 expression in clinical tissue samples was well correlated with depth of myometrial invasion, endometrial invasion, pelvic lymphnode metastasis and tumor vascularity (p < 0.05) and there was a close relation between VEGF-C and MMP-2 expression (p < 0.0001) in cervical carcinomas. Overall survival rates for 14 patients with strong VEGF-C staining tumors were lower than those for 38 patients with weak VEGF-C staining tumors (p = 0.0132) and VEGF-C tissue status emerged as an independent prognostic parameter (p = 0.0232). These results suggest that VEGF-C expression is closely related to invasion phenotype and affects the patient's survival in cervical carcinomas.

Vascular endothelial growth factor C gene expression is closely related to invasion phenotype in gynecological tumor cells

OBJECTIVE

The correlation between the gene expression of various angiogenic factors and in vitro invasive activity in 16 human gynecological cancer cell lines was investigated.

METHODS

Semiquantitative reverse transcription polymerase chain reaction analysis was performed to investigate the mRNA expression levels of vascular endothelial growth factors (VEGF-A, -B, -C, and -D), basic fibroblast growth factor (bFGF), and matrix metalloproteinase (MMP)-2 with beta-actin coamplified as an internal standard. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were evaluated by haptotactic migration and invasion assay.

RESULTS

Expression of VEGF-A mRNA was detected in all 16 cell lines, whereas the relative expression levels of other VEGF family members and bFGF, differed markedly among the cell lines. There was a statistical correlation between VEGF-C gene expression and the number of cells that migrated and invaded (P < 0.01). However, expression of mRNAs of other angiogenic factors did not correlate with motility and invasive activity of the cells. Moreover, there was a close correlation between VEGF-C and MMP-2 gene expression levels (P < 0.05).

CONCLUSION

Tumor cells that produce VEGF-C may have a higher invasive and metastatic potential because of their capacity to pass through tissue barriers.

Correlation between thymidine phosphorylase expression and invasion phenotype in cervical carcinoma cells

The correlation between thymidine phosphorylase (dThdPase) expression and invasion phenotype in human uterine cervical carcinoma cells was investigated using 10 cervical carcinoma cell lines. Semi-quantitative reverse transcription-polymerase chain reaction analysis was performed to investigate the mRNA levels of dThdPase and matrix metalloproteinase (MMP)-2 with beta-actin coamplified as an internal standard. dThdPase protein expression levels were detected by highly sensitive enzyme-linked immunosorbent assay. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were evaluated by haptotactic migration and invasion assay. Although dThdPase mRNA and protein expression levels differed remarkably among the cell lines, there was a statistical correlation between them (r = 0.743, p = 0.0139). dThdPase gene and protein expression levels were well correlated with the number of cells that migrated and invaded (p < 0.05). Moreover, there was a close correlation between MMP-2 gene and dThdPase gene and protein expression levels (p < 0.05). Tumor cells that produce dThdPase may have a higher invasive and metastatic potential because of their capacity to pass through tissue barriers.

Regulation of dihydropyrimidine dehydrogenase and pyrimidine nucleoside phosphorylase activities by growth factors and subsequent effects on 5-fluorouracil sensitivity in tumor cells

Dihydropyrimidine dehydrogenase (DPD) and pyrimidine nucleoside phosphorylase (PyNPase) are the first and rate-limiting enzymes that regulate 5-fluorouracil (5-FU) metabolism, and tumoral DPD activity appears to be a promising predictor of 5-FU sensitivity. However, the regulatory mechanisms determining these enzyme activities have not been fully understood. We investigated the biological effects of epidermal growth factor (EGF) and transforming growth factor (TGF)-alpha on cell growth and tumoral DPD and PyNPase activities, and the subsequent effects on 5-FU sensitivity in uterine cervical carcinoma SKG-IIIb cells. The treatment of tumor cells with EGF or TGF-alpha resulted in a concentration-dependent increase in tumor cell growth and PyNPase activity, whereas tumoral DPD activity was inhibited. Their stimulatory effects on tumor cell growth correlated well with PyNPase activity, but were inversely related to DPD activity (P < 0.01). 5-FU sensitivity of tumor cells increased in the presence of EGF or TGF-alpha. These growth factors were shown to stimulate the first, rate-limiting enzyme activity in 5-FU anabolism and to inhibit that in 5-FU catabolism, leading to enhancement of the antiproliferative action of 5-FU at achievable therapeutic levels. The tumor environmental factors, EGF and TGF-alpha, may act as intrinsic regulators of DPD and PyNPase activities that affect the 5-FU sensitivity of individual tumors.

Expression and function of EGF-related peptides and their receptors in gynecological cancer--from basic science to therapy

EGF-related peptides and their receptors play an important, but not fully understood role, both, in epithelial physiology and pathophysiology but also in human tumor carcinogenesis and tumor behavior, respectively. Overexpression of EGF-related growth factors from normal epithelium to carcinomas has been demonstrated for several human tissues such as breast, endometrium, cervix and ovary. Additionally, the differential overexpression of EGFR or erb B-2 in various malignancies has already proven to be efficacious in stratifying patients with respect to a poor prognosis. These data suggest that EGF-related growth factors, erb B receptors or signaling proteins that function either upstream or downstream from these receptors may represent novel targets for selective tumor therapy. In the future, conventional chemotherapy regimes will ultimately be wedded to more biologically-oriented therapies. One important target for these novel therapeutic approaches in solid tumors will be the EGF-related growth factors and their receptors.

Correlation between tumor angiogenesis and expression of thymidine phosphorylase, and patient outcome in uterine cervical carcinoma

The relationship between tumor angiogenesis and the expression of thymidine phosphorylase (dThdPase) in uterine cervical carcinoma tissues, as well as patient outcome, were investigated. Primary tumor specimens surgically obtained from 54 patients (stages Ib to IIIb) receiving neither chemotherapy nor radiation therapy before surgery were examined. Intratumoral microvessel density (IMVD) and dThdPase expression were evaluated immunohistochemically using anti-CD34 and anti-dThdPase antibodies and were correlated with clinicopathologic parameters and prognosis. IMVD for the 54 tumors ranged from 24.8 to 118.6, with a median value of 57.7 (number/0.7386 mm2/field). For immunoreactivity of dThdPase, 16 tumors were graded as -, 20 as 1+, and 18 as 2+. IMVD was significantly associated with the expression of dThdPase (P<.01). Both IMVD and dThdPase expression were well correlated with depth of myometrial invasion, endometrial invasion, and pelvic lymphnode metastasis (P<.05). Overall survival rates for 18 patients with strong dThdPase-staining tumors, assessed as 2+, were lower than those for 36 with weak dThdPase staining tumors (P = .0108). However, there was no statistical correlation between IMVD and patient outcome. The expression of dThdPase plays a role in the promotion of angiogenesis and affects the patient's survival in uterine cervical carcinomas.

Autocrine and paracrine motility factors and their involvement in invasiveness in a human oral carcinoma cell line

Invasive potentials of malignant cancer cells are regulated by cell motility factors. To examine the regulation of motility and invasiveness in oral squamous carcinoma, we investigated autocrine- and/or paracrine-acting cell motility factors, using a newly established human cell line (IF cells) from oral squamous cell carcinoma, which has highly invasive and metastatic characteristics. Conditioned medium derived from IF cells stimulated cell scattering and migration of GB-d1 gallbladder carcinoma cells, indicating that IF cells secreted cell motility factors. Using antibodies, IF-derived cell motility factors proved to be transforming growth factor (TGF)-alpha and TGF-beta1. Antibodies against TGF-alpha and TGF-beta1 inhibited autonomous migration of the IF cells. On the other hand, in vitro invasion of IF cells was strongly enhanced by hepatocyte growth factor (HGF) but only slightly by TGF-alpha and TGF-beta1. The conditioned medium from fibroblasts enhanced in vitro invasion of IF cells, an event abrogated by anti-HGF antibody, but not by antibodies against TGF-alpha and TGF-beta1. Importantly, IF cells secreted a factor inducing HGF production in fibroblasts and the factor was identified as interleukin-1, which means that a mutual interaction exists between tumour cells and fibroblasts, as mediated by the HGF/HGF-inducer loop. These results indicate that IF cells utilize TGF-alpha and TGF-beta1 as autocrine-acting motility factors and HGF as a paracrine-acting motility factor, and that invasiveness of IF cells is particularly stimulated by HGF derived from stromal fibroblasts. Utilization of multiple cell motility/invasion factors that act in distinct pathways may confer highly invasive and metastatic potentials in IF oral squamous carcinoma cells.

Matrix metalloproteinase 2 (MMP2) and MMP9 are produced by kidney collecting duct principal cells but are differentially regulated by SV40 large-T, arginine vasopressin, and epidermal growth factor

We analyzed the expression and regulation of matrix metalloproteinase 2 (MMP2) and MMP9 gelatinases in a rabbit kidney collecting duct principal cell line (RC.SVtsA58) (Prié, D., Ronco, P. M., Baudouin, B., Géniteau-Legendre, M., Antoine, M., Piedagnel, R., Estrade, S., Lelongt, B., Verroust, P. J., Cassingéna, R., and Vandewalle, A. (1991) J. Cell Biol. 113, 951-962) infected with the temperature-sensitive (ts) SV40 strain tsA58. At the permissive temperature (33 degreesC), cells produced only MMP2. Shifting cells to a nonpermissive temperature (39.5 degreesC) induced a marked increase in total gelatinolytic activity due to an increase of MMP2 and an induction of MMP9 synthesis. This effect was attributed to large-T inactivation at 39.5 degreesC because it was abolished by re-infecting the cells with wild-type SV40 strain LP. Run-on experiments showed that negative regulation of MMP2 and MMP9 by large-T was transcriptional and posttranscriptional, respectively. MMP2 and MMP9 were also produced by primary cultures of collecting duct cells. In rabbit kidney, both MMP2 and MMP9 were almost exclusively expressed in collecting duct cells, where an unexpected apical localization was observed. Arginine vasopressin and epidermal growth factor, which exert opposite hydroosmotic effects in the collecting duct, also exhibited contrasted effects on MMP9 synthesis. Epidermal growth factor increased but arginine vasopressin suppressed MMP9 at a posttranscriptional level, whereas MMP2 was not affected. These results suggest a specific physiological role of MMP2 and MMP9 in principal cells of renal collecting duct.