Role of thymidine phosphorylase on invasiveness and metastasis in lung adenocarcinoma

Thymidine phosphorylase promotes angiogenesis and tumour growth in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer, and thymidine phosphorylase (TP) is a regulator of angiogenesis. To investigate the biological activities of TP in ICC, we established human cholangiocarcinoma RBE cell lines overexpressing TP or silencing TP. Overexpression of TP enhanced viability, suppressed apoptosis and increased tube formation in human umbilical vein endothelial cells, while downregulation of TP reversed these effects. Moreover, an orthotopic xenograft mouse model of ICC was built to further explore TP's function in ICC in vivo. Histological analysis using H&E, TUNEL and Ki67 staining showed that TP promoted tumour growth and inhibited cell apoptosis. Immunostaining for CD31 revealed an elevation in microvessel density in the presence of TP. Besides, upregulation of TP increased the expression of vascular endothelial growth factor, basic fibroblast growth factor, interleukin-8 and tumour necrosis factor alpha. In contrast, TP knockdown inhibited tumour growth, suppressed microvessel formation and decreased the expression of angiogenesis-related proteins. Therefore, we suggest that TP promotes angiogenesis and tumour growth in ICC, which can be a potent therapeutic target for ICC treatment.

Specificity protein 1: Its role in colorectal cancer progression and metastasis

Specificity protein 1 (Sp1) is a widely expressed transcription factor that plays an important role in the promotion of oncogenes required for tumor survival, progression and metastasis. Sp1 is highly expressed in several cancers including colorectal cancer (CRC) and is related to poor prognosis. Therefore, targeting Sp1 is a rational for CRC therapy. In this review, we will recapitulate the current understanding of Sp1 signaling, its molecular mechanisms, and its potential involvement in CRC growth, progression and metastasis. We will also discuss the current therapeutic drugs for CRC and their mechanism of action via Sp1.

Therapeutic potential of TAS-102 in the treatment of gastrointestinal malignancies

Fluoropyrimidines form the mainstay in treatment of gastrointestinal malignancies. For decades 5-fluorouracil (5FU), was the major fluoropyrimidine. Currently it is usually given in a combination with leucovorin and oxaliplatin, i.e. FOLFOX, or irinotecan, i.e. FOLFIRI, or all three, i.e. FOLFIRINOX, but gradually it has been replaced by oral fluoropyrimidine prodrug formulations, such as tegafur-uracil and S-1 (both contain ftorafur), and capecitabine (Xeloda®). Novel drugs such as the antivascular endothelial growth factor antibody, bevacizumab, and the anti-epidermal growth factor receptor antibody, cetuximab, are often combined with one of these treatment options. However, when resistance emerged, no alternatives were available. TAS-102, a combination of trifluorothymidine and the thymidine phosphorylase inhibitor TPI in a 1:0.5 ratio, is a novel oral formulation, which is active in 5FU-resistant models, both in vitro and in xenograft models. In addition to inhibition of thymidylate synthase, the major mechanism of action of classical fluoropyrimidines, TAS-102's major mechanism of action is incorporation into DNA, thereby causing DNA damage. TAS-102 also follows an alternative activation pathway via thymidine kinase, and is not a substrate for dihydropyrimidine dehydrogenase. All together this explains the efficacy in 5FU-resistant models. In early clinical studies, the twice-daily schedule (5 days on, 2 days rest) for 2 weeks every 4 weeks, led to a significant disease control rate in various malignancies. This schedule showed consistent activity in two randomized trials on fluoropyrimidine refractory colorectal cancer patients, reflected by an increase of 2-3 months in overall survival in the TAS-102 group compared with placebo. Considering the impressive preclinical potential of various combinations TAS-102 has the promise to become an alternative for 5FU-resistant cancer.

Thymidine Phosphorylase in Cancer; Enemy or Friend?

Thymidine phosphorylase (TP) is a nucleoside metabolism enzyme that plays an important role in the pyrimidine pathway.TP catalyzes the conversion of thymidine to thymine and 2-deoxy-α-D-ribose-1-phosphate (dRib-1-P). Although this reaction is reversible, the main metabolic function of TP is catabolic. TP is identical to the angiogenic factor platelet-derived endothelial-cell growth factor (PD-ECGF). TP is overexpressed in several human cancers in response to cellular stressful conditions like hypoxia, acidosis, chemotherapy and radiotherapy. TP has been shown to promote tumor angiogenesis, invasion, metastasis, evasion of the immune-response and resistance to apoptosis. Some of the biological effects of TP are dependent on its enzymatic activity, while others are mediated through cytokines like interleukin 10 (IL-10), basic fibroblast growth factor (bFGF) and tumour necrosis factor α (TNFα). Interestingly, TP also plays a role in cancer treatment through its role in the conversion of the oral fluoropyrimidine capecitabine into its active form 5-FU. TP is a predictive marker for fluoropyrimidine response. Given its various biological functions in cancer progression, TP is a promising target in cancer treatment. Further translational research is required in this area.

Identification of proteins expressed differently among surgically resected stage I lung adenocarcinomas

RATIONALE

Among patients with surgically resected stage I lung adenocarcinoma, some succumb to early recurrence, while others survive for more than 5 years. Few markers to predict prognoses in these patients have been accepted. Recent advances in proteomic methodologies offer a unique chance to identify new candidate biomarkers. The aim of this study is to find differences in protein expression in resected lung cancer tissue of stage I adenocarcinoma from patients with no recurrence for more than 5 years and from those with early recurrence.

METHODS

Lung cancer tissues were obtained from 15 patients with pathologically confirmed stage I adenocarcinoma. The patients were divided into two groups, those with recurrence within 36 months (early recurrence group, n=9) and those that were disease-free for over 5 years (disease free group, n=6). Tissue proteins were separated by a two-dimensional electrophoresis long gel system (30 × 40 cm) with set ranges (3-10 NL) and examined by nano-LC-ESI-MS/MS. Western blot assays were performed to validate these proteins.

RESULTS

Twelve protein spots were up-regulated and 8 were down-regulated in the disease-free group as compared with the recurrence group. Of the 12 up-regulated proteins, haptoglubin, tau-tubulin kinase-2 (TTBK2), thymidine phosphorylase, annexin-1, PIN1, CAPG, and SEC23 were validated by Western blot. Among the 8 down-regulated proteins, serpinB6 and trangelin-2 were validated.

CONCLUSIONS

A total of 9 differentially expressed proteins were successfully extracted, identified, and confirmed from stage I lung adenocarcinoma tissues. The increased or decreased expression of these proteins according to prognosis may be the basis for further studies of proteomics in developing prognostic biomarkers.

Proteomic profile regulated by the anticancer peptide CIGB-300 in non-small cell lung cancer (NSCLC) cells

CIGB-300 is a proapoptotic peptide-based drug that abrogates the CK2-mediated phosphorylation. This peptide has antineoplastic effect on lung cancer cells in vitro and in vivo. To understand the mechanisms involved on such anticancer activity, the NCI-H125 cell line proteomic profile after short-term incubation (45 min) with CIGB-300 was investigated. As determined by 2-DE or 2D-LC-MS/MS, 137 proteins changed their abundances more than 2-fold in response to the CIGB-300 treatment. The expression levels of proteins related to ribosome biogenesis, metastasis, cell survival and proliferation, apoptosis, and drug resistance were significantly modulated by the presence of CIGB-300. The protein translation process was the most affected (23% of the identified proteins). From the proteome analysis of the NCI-H125 cell line, novel potentialities for CIGB-300 as anticancer agent were evidenced.

Effects of thymidine phosphorylase on tumor aggressiveness and 5-fluorouracil sensitivity in cholangiocarcinoma

AIM: To evaluate the role of thymidine phosphorylase (TP) in cholangiocarcinoma using small interfering RNA (siRNA).

METHODS: A human cholangiocarcinoma-derived cell line KKU-M139, which has a naturally high level of endogenous TP, had TP expression transiently knocked down using siRNA. Cell growth, migration, in vitro angiogenesis, apoptosis, and cytotoxicity were assayed in TP knockdown and wild-type cell lines.

RESULTS: TP mRNA and protein expression were decreased by 87.1% ± 0.49% and 72.5% ± 3.2%, respectively, compared with control cells. Inhibition of TP significantly decreased migration of KKU-M139, and suppressed migration and tube formation of human umbilical vein endothelial cells. siRNA also reduced the ability of TP to resist hypoxia-induced apoptosis, while suppression of TP reduced the sensitivity of KKU-M139 to 5-fluorouracil.

CONCLUSION: Inhibition of TP may be beneficial in decreasing angiogenesis-dependent growth and migration of cholangiocarcinoma but may diminish the response to 5-fluorouracil chemotherapy.

Clinical significance of PD-ECGF expression in human pancreatic carcinoma

AIM: To investigate the expression of platelet-derived endothelial cell growth factor (PD-ECGF) in human pancreatic carcinoma and evaluate its clinical significance.

METHODS: Immunohistochemistry was used to detect the expression of PD-ECGF in 36 paraffin-embedded pancreatic carcinoma specimens, 21 tumor-adjacent normal tissue specimens, and 60 cancerous specimens derived from other tissues (stomach, colon, esophagus, liver, lung and breast; 10 specimens each). The expression of PD-ECGF in different tissues was compared. The correlation between PD-ECGF expression and clinical parameters in pancreatic carcinoma was analyzed.

RESULTS: The positive rate of PD-ECGF in pancreatic carcinoma was higher than that in tumor-adjacent normal tissue (88.9% vs 28.6%, P < 0.01). The positive rates of PD-ECGF in cancerous colon, liver, breast, esophagus, stomach and lung tissues were 60%, 70%, 80%, 90%, 90% and 80%, respectively. The positive rate of PD-ECGF in pancreatic carcinoma at stage II-IV was higher than that at stage I (100% vs 75%, P < 0.05).

CONCLUSION: PD-ECGF is an organ-unspecific tumor-associated protein that may be associated with the progression of pancreatic carcinoma.

The dual role of thymidine phosphorylase in cancer development and chemotherapy

Thymidine phosphorylase (TP), also known as "platelet-derived endothelial cell growth factor" (PD-ECGF), is an enzyme, which is upregulated in a wide variety of solid tumors including breast and colorectal cancers. TP promotes tumor growth and metastasis by preventing apoptosis and inducing angiogenesis. Elevated levels of TP are associated with tumor aggressiveness and poor prognosis. Therefore, TP inhibitors are synthesized in an attempt to prevent tumor angiogenesis and metastasis. TP is also indispensable for the activation of the extensively used 5-fluorouracil prodrug capecitabine, which is clinically used for the treatment of colon and breast cancer. Clinical trials that combine capecitabine with TP-inducing therapies (such as taxanes or radiotherapy) suggest that increasing TP expression is an adequate strategy to enhance the antitumoral efficacy of capecitabine. Thus, TP plays a dual role in cancer development and therapy: on the one hand, TP inhibitors can abrogate the tumorigenic and metastatic properties of TP; on the other, TP activity is necessary for the activation of several chemotherapeutic drugs. This duality illustrates the complexity of the role of TP in tumor progression and in the clinical response to fluoropyrimidine-based chemotherapy.

Thymidine kinase 1 and thymidine phosphorylase expression in non-small-cell lung carcinoma in relation to angiogenesis and proliferation

The thymidine salvage pathway enzymes thymidine kinase 1 (TK1) and thymidine phosphorylase (TP) compete for thymidine as a substrate and catalyze opposing synthetic and catabolic reactions that have been implicated in the control of proliferation and angiogenesis, respectively. We investigated the relationship between the expression of TK1 and TP as they relate to proliferation (Ki-67 labeling index) and angiogenesis (Chalkley count of CD31-stained blood vessels) in a series of 110 non-small-cell lung cancer (NSCLC) tumors from patients prospectively enrolled in an imaging trial. TK1 and TP exhibited similar patterns of immunohistochemical distribution, in that each was found in both the nucleus and the cytoplasm of tumor cells. Each enzyme exhibited a significant positive correlation between its levels of nuclear and cytoplasmic expression. A significant positive correlation between TK1 expression and the Ki-67 labeling index (r = 0.53, p<0.001) was observed. TP was significantly positively correlated with Chalkley scoring of CD31 staining in high vs low Chalkley scoring samples (mean TP staining of 115.8 vs 79.9 scoring units, p<0.001), respectively. We did not observe a substantial inverse correlation between the TP and TK1 expression levels in the nuclear compartment (r = -0.17, p=0.08). Tumor size was not found to be associated with TK1, TP, Ki-67, or Chalkley score. These findings provide additional evidence for the role of thymidine metabolism in the complex interaction of proliferation and angiogenesis in NSCLC.

Angiogenic factor thymidine phosphorylase increases cancer cell invasion activity in patients with gastric adenocarcinoma

We investigated the biological role of thymidine phosphorylase (TP), an angiogenic factor, in gastric cancer cell migration and invasion and explored a therapeutic approach for high TP-expressing tumors using TP enzymatic inhibitor (TPI) and rapamycin. We established TP cDNA overexpressing gastric cancer cell lines (MKN-45/TP and YCC-3/TP) and did invasion and adhesion assays with Matrigel-coated transwell membranes. The related signal pathway using recombinant human TP (rhTP), deoxy-d-ribose (D-dRib), and signal pathway inhibitors (wortmannin, LY294002, and rapamycin) was investigated. First, AGS and MKN-1 gastric cancer cell lines showed dose-dependent up-regulation of invasiveness through Matrigel following treatment with rhTP or D-dRib. TP-overexpressing cancer cell lines displayed increased migration and invasion activity, which doubled with rhTP and D-dRib treatment. This activity depended on the enzymatic activity of TP, and TP stimulated the adhesion of cancer cells onto Matrigel and induced actin filament remodeling. Finally, we showed that this activity is related to increased phosphatidylinositol 3-kinase activity in TP-overexpressing cells and that combination treatment with rapamycin and TP enzymatic inhibitor produces an additive effect to abrogate TP-induced invasion. Taken together, TP increases the migration and invasion of gastric cancer cells, especially in TP-expressing cells. Therapies targeting TP might diminish the propensity for invasion and metastasis in gastric cancer.

Heterogeneous ribonucleoprotein k and thymidine phosphorylase are independent prognostic and therapeutic markers for nasopharyngeal carcinoma

PURPOSE

Heterogeneous ribonucleoprotein K (hnRNP K) regulates thymidine phosphorylase (TP) mRNA stability. The aim of the present study was to analyze hnRNP K and TP expression in nasopharyngeal carcinoma (NPC) and to evaluate the prognostic and therapeutic potential of these two markers.

EXPERIMENTAL DESIGN

We analyzed hnRNP K and TP expression immunohistochemically in 121 clinically proven NPC cases. Statistical analyses were applied to correlate cytoplasmic hnRNP K with elevated TP expression and determine the prognostic significance of these parameters. The therapeutic implication of elevated TP expression was determined by measuring sensitivity of NPC cells to the TP-targeting drug, 5-fluoro-5'-deoxyuridine (5'-DFUR).

RESULTS

There was a high correlation between cytoplasmic hnRNP K and high TP (P < 0.001). Both cytoplasmic hnRNP K and high TP were associated with poor overall survival (OS; P = 0.007 and P < 0.001, respectively) and distant metastasis-free survival (P = 0.003 and 0.001, respectively) of NPC patients. A multivariate analysis confirmed that both cytoplasmic hnRNP K and high TP are independent prognostic predictors for OS (P = 0.020 and 0.010, respectively). NPC cells expressing high TP were more sensitive to treatment with the TP-targeting drug, 5'-DFUR.

CONCLUSIONS

Cytoplasmic hnRNP K and high TP are associated with shorter OS and distant metastasis-free survival in NPC patients. In vitro experiments suggest that NPC tumors with high TP expression may be sensitive to 5'-DFUR treatment. Cytoplasmic hnRNP K and high TP may be potential prognostic and therapeutic markers for NPC, but additional validation studies are warranted.

Genomic alterations in lung adenocarcinomas detected by multicolor fluorescence in situ hybridization and comparative genomic hybridization

We used two molecular cytogenetic techniques, multicolor fluorescence in situ hybridization (M-FISH) and comparative genomic hybridization (CGH), to analyze three established lung adenocarcinoma cell lines (A549, H1650, and SPC-A-1) and primary lung adenocarcinoma samples, to identify common chromosomal aberrations. M-FISH revealed numerous complex chromosomal rearrangements. Chromosomes 5, 6, 11, 12, and 17 were most frequently involved in interchromosomal translocations. CGH revealed regions on 1q, 2p, 3q, 5p, 5q, 7p, 8q, 11q, 12q, 14q, 16p, 17p, 19q, 20q, 21q, and 22q to be commonly overrepresented and regions on 2q, 3p, 4p, 5q, 7q, 8p, 9p, 13q, 14q, and 17p to be underrepresented. The most common gains were found in 16p13 (in 50% of samples), and 16p13 amplification was associated with relatively poor differentiation and late stage. M-FISH and CGH can be a powerful tool in identification of genomic alterations in lung cancer, as well as in diagnosis. The overrepresented regions may harbor potential candidate genes involved in lung adenocarcinoma pathogenesis.

Therapeutic potential of the dual-targeted TAS-102 formulation in the treatment of gastrointestinal malignancies

Current treatment modalities for cancer combine cytotoxic drugs against DNA and novel targeted drugs affecting signal transduction pathways, which are required for growth progression and metastasizing tumors. Classical chemotherapeutic regimens for gastro-intestinal tumors include antimetabolites based on 5-fluorouracil (5FU), the platinum analog oxaliplatin and the topoisomerase inhibitor irinotecan. The thymidine analog trifluorothymidine (TFT) has been shown to bypass resistance pathways for 5FU derivatives (S-1, UFT, Xeloda) in model systems, while concurrent application with a thymidine phosphorylase inhibitor (TPI) increases the bioavailability of TFT, thereby potentiating the in vivo efficacy of TFT. The formulation TAS-102 is given orally in a 1.0:0.5 molar ratio (TFT:TPI). The formulation is dual-targeted due to the cytotoxic effect of TFT, which is enhanced by TPI, while TPI also exerts antiangiogenic effects by inhibiting thymidine phosphorylase (TP), also known as platelet-derived endothelial cell growth factor. Evidence is accumulating from in vitro and in vivo preclinical studies that these properties favor further combinations with other cytotoxic agents currently being used in the treatment of gastro-intestinal tumors. Also treatment with targeted agents will synergistically down-regulate signal transduction pathways responsible for growth and progression of tumors. In this review, we summarize the available information on (clinical) pharmacology, mechanisms of action, pharmacodynamic and pharmacokinetic properties, early clinical trials and future directions of the new potent combination drug TAS-102.

Clarithromycin suppresses invasiveness of human lung adenocarcinoma cells

BACKGROUND

It has been speculated that clarithromycin (CAM), a 14-membered ring macrolide, possesses antitumor effects besides antimicrobial and anti-inflammatory effects.

METHOD

We evaluated the effects of CAM on the growth and invasiveness of A549 lung adenocarcinoma cells.

RESULTS

Although CAM did not affect the growth of A549 cells, the Matrigel invasion assay showed that the potential of invasion was diminished by CAM treatment. When analyzed by flow cytometry, CAM suppressed alpha(2)- and beta(1)-integrin expression. Furthermore, thymidine phosphorylase (TP) expression was diminished by CAM treatment in a dose-dependent manner. A specific TP inhibitor also suppressed beta(1)-integrin expression in flow cytometric analysis.

CONCLUSIONS

These results suggest that CAM may suppress invasive activity of A549 cells in part by diminishing the expression of TP, alpha(2)- and beta(1)-integrin, which may be a downstream signal of the TP pathway, and that CAM could be useful in the treatment of lung adenocarcinoma.

The Hollow Fibre Assay as a model for in vivo pharmacodynamics of fluoropyrimidines in colon cancer cells

The Hollow Fibre Assay (HFA) is usually applied as an early in vivo model for anti-cancer drug screening, but is potentially an excellent model for short-term in vivo pharmacodynamic studies. We used the model to study the in vivo role of thymidine phosphorylase/platelet-derived endothelial cell growth factor (TP/PD-ECGF) in the cytotoxicity and pharmacodynamics of TAS-102 in colon cancer cells. TAS-102 is a new oral drug formulation, which is composed of trifluorothymidine (TFT) and thymidine phosphorylase inhibitor (TPI), which prevents TFT degradation. We compared the activity with Xeloda (capecitabine), which is activated by TP into 5FU. Hollow fibres filled with human Colo320 or Colo320TP1 colorectal cancer cells with deficient or high TP expression, respectively, were implanted subcutaneously (s.c.) at both flanks of BALB/c mice. The mice were treated orally over 5 days with TAS-102, TFT alone, 5′DFUR±TPI or capecitabine at their maximum tolerated dose (MTD). The cells were retrieved from the fibres and assayed for growth (MTT assay), cell cycle distribution (flow cytometry) and apoptosis induction (FragEL method). TAS-102 induced considerable growth inhibition (50%, P<0.01) to both cell lines, which was completely abolished in the absence of TPI. Capecitabine and its metabolite 5′DFUR reduced proliferation of Colo320TP1 cells in the fibres significantly (down to 25–40%), but much less in Colo320 cells, whereas addition of TPI reduced the effect of 5′DFUR, although not completely. These differences in cytotoxic effects were reflected in the pharmacodynamic evaluation. TAS-102 induced a G2M-phase arrest (from 25 to 40%) and apoptosis (>8-fold), which was more pronounced in Colo320 than in Colo320TP1. Again, omission of TPI neutralised the effect of TAS-102. Similarly, 5′DFUR and capecitabine induced a significant G2M-phase arrest (up to 45%) in the Colo320TP1 cell line, but less pronounced in the parental Colo320. Addition of TPI to 5′DFUR reduced this effect to control levels. Also induction of apoptosis was reduced in the presence of TPI. The data demonstrated that the HFA is excellently suited for studying short-term pharmacodynamic effects of fluoropyrimidines in vivo. TAS-102 is only effective in inducing cytotoxicity when systemic TPI is present, but acts against both low and high TP expressing colon cancer cells, while 5′DFUR needs cellular TP to exert significant activity.

Comparative Genomic Hybridization Array Analysis and Real-Time PCR Reveals Genomic Copy Number Alteration for Lung Adenocarcinomas

Genomic alterations in lung cancer tissues have been observed in various studies. To analyze the aberrations in the genome of lung cancer patients, we used array comparative genomic hybridization (array CGH) in 15 lung adenocarcinoma (AdC) tissues. Copy number gains and losses in chromosomal regions were detected and corresponding genes were confirmed by real-time polymerase chain reaction (PCR). As for the results, several frequently altered loci, including gain of 16p (46% of samples), were found, and the most common losses were found in 14q32.33 (26% of samples). High-level DNA amplifications (> 0.8 log(2) ratio) were detected at 1p, 5p, 7p, 9p, 11p, 11q, 12q, 14q, 16p, 17q, 19q, 20p, 21q, and 22q. A subset of genes, gained or lost, was checked for over- or underrepresentation by means of real-time PCR. The degree of fold change was highest in ECGF1 (22q13.33), HOXA9 (7p15.2), MAFG (17q25.3), TSC2 (16p13.3), and ICAM1 (19p13.2) genes and the 16p chromosome terminal region (16p13.3pter). Taken together, these results show that array CGH could be used as a powerful tool for identification of genomic alteration for lung cancer, and the above-mentioned genes may represent potential candidate genes in the study of lung cancer pathogenesis and diagnosis.

2-Deoxy-L-ribose inhibits the invasion of thymidine phosphorylase-overexpressing tumors by suppressing matrix metalloproteinase-9

Thymidine phosphorylase (TP), an enzyme involved in pyrimidine metabolism, is identical with an angiogenic factor, platelet-derived endothelial cell growth factor. 2-Deoxy-D-ribose (D-dRib), the degradation product of thymidine generated by TP activity, has been suggested to be a downstream mediator of TP function. 2-Deoxy-L-ribose (L-dRib), a stereoisomer of D-dRib, inhibited the promotion of angiogenesis, tumor growth and metastasis by TP. In our study, we have shown that nude mice inoculated with TP-overexpressing KB/TP cells had shorter survival times than those injected with control KB/CV cells. KB/TP tumors were also more highly invasive than KB/CV tumors in mice. The expression levels of matrix metalloproteinase (MMP)-9 in KB/TP tumors were significantly higher than those in KB/CV tumors. L-dRib and a TP inhibitior, TPI, extended the survival period of KB/TP tumor-bearing mice. L-dRib also reduced MMP-9 mRNA levels in KB/TP tumors. Furthermore, L-dRib suppressed the mRNA level of MMP-9 in cultured KB/TP cells, and the invasive activity of the cells. L-dRib may be useful for the suppression of invasion of TP-expressing tumor cells.

Amplification of D22S283 as a favorable prognostic indicator in liver fluke related cholangiocarcinoma

AIM: To analyze the DNA copy number of target genes NF2, TIMP3, ST13, TOB2, BIK, and TP and the reference microsatellite markers D22S283, D22S423, and D22S274 mapped on 22q12-qter in liver fluke related cholangiocarcinoma (CCA) and define its correlation with clinical parameters.

METHODS: Quantitative real time PCR (qPCR) was used for determining allelic imbalances in 65 liver fluke related CCA tissues. Statistical correlations between allelic imbalances and clinicopathological parameters, i.e. age, sex, tumor stage, histological type, blood vessel invasion, nerve invasion and lymphatic invasion were evaluated by means of the χ² test. Cox regression analysis was used for determining patient’s survival.

RESULTS: Amplifications of the TP (22q13.33), TOB2 (22q13.2-13.31), D22S283 (22q12.3), TIMP3 (22q12.3) and NF2 (22q12.2) were found in 35 (53.8%), 28 (43.1%), 27 (41.5%), 24 (36.9%), and 24 (36.9%), respectively. Losses at the D22S423 (22q13.1-13.2) and BIK (22q13.31) were detected in 26 (40%) and 23 (35.4%), respectively. Significant correlations were observed between lymphatic invasion and allelic losses of BIK (P = 0.025) and D22S283 (P = 0.041). Univariate and multivariate Cox regression analysis revealed D22S283 amplification as an independent predictor of good prognosis (P = 0.006, death hazard ratio = 0.411, 95% CI = 0.217-0.779) and blood vessel invasion as an independent poor prognostic factor (P = 0.042, death hazard ratio = 1.911, 95% CI = 1.022-3.571) in CCA patients.

CONCLUSION: This study provides evidence for the involvement of gene amplification and deletion on chromosome 22q in liver fluke related CCA. This is the first report of D22S283 amplification as an independent indicator of favorable prognosis in liver fluke related CCA.

Combined GADD45A and thymidine phosphorylase expression levels predict response and survival of neoadjuvant-treated gastric cancer patients

PURPOSE

We evaluated the expression of seven therapy-related genes to predict the clinical outcome of advanced gastric cancer patients treated with a neoadjuvant chemotherapeutic protocol.

EXPERIMENTAL DESIGN

Pretherapeutic, formalin-fixed, and paraffin-embedded biopsies of 61 patients, who received a 5-fluorouracil (5-FU)- and cisplatin-based chemotherapy were studied. The expressions of the 5-FU-related genes TS, DPD, and TP and of the cisplatin-related genes ERCC1, ERCC4, KU80, and GADD45A were analyzed by quantitative real-time PCR. The expression levels of single genes and of various combinations were tested for an association with response and overall survival.

RESULTS

High DPD levels were more frequently found in nonresponding patients and were associated with worse survival. GADD45A and TP levels showed weak associations with response, but GADD45A expression correlated with survival. There was no association with response for TS expression, but tumors with a high TS level were associated with worse survival. The combination of GADD45A and TP revealed the strongest predictive effect. High expression values of TP and/or GADD45A were exclusively found in nonresponding patients (P = 0.002) and were associated with a significantly poorer survival (P = 0.04).

CONCLUSIONS

Combined gene expression levels of TP and GADD45A represent a new variable to predict the clinical outcome after neoadjuvant chemotherapy in gastric cancer. The association of DPD expression with response and survival underlines a predominant role of DPD to predict 5-FU sensitivity. The association of TS expression levels with survival but not with response suggests an importance of this gene for tumor progression.

Thymidine phosphorylase expression in tumour cells and tumour response to capecitabine plus docetaxel chemotherapy in non-small cell lung cancer

BACKGROUND

Thymidine phosphorylase (TP) is the key enzyme for capecitabine activation in tumour cells.

AIMS

To examine whether TP expression in tumour cells and stroma is predictive of the tumour response to capecitabine plus docetaxel chemotherapy in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Tumour samples were available from 30 of 39 patients enrolled in a previous phase II study of capecitabine/docetaxel chemotherapy in patients with advanced NSCLC. Stromal and tumour cell TP expression was evaluated by immunohistochemistry using monoclonal antibody PD-ECGF.

RESULTS

High tumour cell TP expression was found in 13 of 30 cases and was negatively associated with stromal TP expression (p = 0.000). High stromal TP expression was found in 16 of 28 cases and was strongly associated with intense macrophage infiltration (p = 0.002), suggesting that macrophages are the major component of TP expression in the stroma. Tumour response to capecitabine/docetaxel was significantly associated with high tumour cell TP expression (p = 0.004) and low stromal TP expression (p = 0.009). Moreover, high tumour cell TP expression was significantly associated with severe hand-foot syndrome, a toxic side effect of capecitabine (p = 0.01). Improved survival was seen for high tumour cell and low stromal TP expression, although results were not significant (p = 0.6 and 0.3, respectively).

CONCLUSIONS

In advanced NSCLC, TP expression in tumour cells and stroma is associated with tumour response to capecitabine/docetaxel chemotherapy, and might be a useful predictor of tumour response to capecitabine based chemotherapy. A large scale prospective study is needed to confirm the prognostic significance of TP expression in NSCLC.

Increased expression of mRNA specific for thymidine kinase, deoxycytidine kinase or thymidine phosphorylase in human papillary thyroid carcinoma

The aim of the present study was to estimate the expression of mRNA, specific for thymidine kinase 1 (TK1), deoxycytidine kinase (dCK), and thymidine phosphorylase (dThdPase), i.e. enzymes involved in pyrimidine and purine metabolism in human papillary thyroid carcinoma (PTC) tissue. Additionally, the expression of dCK was estimated, in medullary thyroid carcinoma (MTC). For control, the RNA expression levels for all the enzymes were measured in macroscopically unchanged thyroid tissue. Reverse transcriptase-polymerase chain reaction (RT-PCR) and densitometry were employed for mRNA expression measurements, with the beta-actin gene as a control housekeeping gene. The levels of mRNA expression for TK1, dCK and dThdPase in human PTC, as well as mRNA expression for dCK in MTC, were significantly higher than mRNA expressions for those enzymes found in macroscopically unchanged thyroid tissue. It is concluded that an increased expression of mRNA, specific for TK1, dCK and dThdPase, may be involved in carcinogenic processes in the human thyroid.

Correlation between 99mTc-(V)-DMSA uptake and constitutive level of phosphorylated focal adhesion kinase in an in vitro model of cancer cell lines

PURPOSE

Although a number of prognostic indicators have been developed, it is still difficult to predict the biological behaviour of all cancer types.( 99m)Tc-(V)-DMSA (V DMSA) uptake and focal adhesion kinase (FAK) expression and activation level could be potential agents for this purpose. We hypothesised the existence of a correlation between V DMSA, whose uptake is linked to phosphate ions, essential compounds for tumour growth and cell proliferation, and the adhesion protein FAK, whose elevated expression and level of constitutive activation are implicated in cancer progression. The aim of this study was to assess the relationship between V DMSA incorporation rate and FAK expression and activation by phosphorylation on tyrosine 397 residue.

METHODS

We determined V DMSA uptake in six different cancer cell lines and we measured FAK expression and activation by using Western Blotting analysis. Correlations with factors known to be associated with poor prognosis, such as invasive potential, resistance to chemotherapy and proliferation rate, were also investigated.

RESULTS

The cell lines exhibited different V DMSA incorporation rates. In addition, these cells showed the same FAK expression, but various degrees of activation. A correlation was observed between V DMSA uptake and level of FAK phosphorylation and between V DMSA or constitutive FAK activation and proliferation rate. However, no correlation was shown between these parameters and the other factors tested, i.e. invasive potential and anticancer drug resistance.

CONCLUSION

The results of this in vitro study clearly demonstrate that phosphorylation of FAK, proliferation rate and V DMSA uptake are closely related. Because proliferation and a high level of constitutive FAK activation are linked to cancer progression, it can be assumed that in vivo V DMSA uptake reflects tumour aggressiveness.

Correlation of platelet-derived endothelial cell growth factor/ thymidine phosphorylase and Cox-2 expression to angiogenesis and apoptosis in gastric carcinoma

AIM: To investigate the relationship of the expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase (PD-ECGF/TP) and Cox-2 to angiogenesis and apoptosis in gastric carcinoma.

METHODS: The expression of PD-ECGF and Cox-2 and the microvascular density (MVD) level were examined by immunohistochemical staining, and apoptotic index (AI) was examined by flow cytometry in 67 cases of gastric carcinoma.

RESULTS: There was a close correlation between PD-ECGF expression and several clinicopathological factors including lymph node metastasis (P < 0.05), histology (P < 0.05) and histological type (P < 0.05). The expression of Cox-2 was closely related to lymph node metastasis (P < 0.05); The expression of PD-ECGF or Cox-2 in gastric cancer tissues was positively correlated with MVD (P < 0.01) and negatively correlated with AI (P < 0.01). Combined analysis of PD-ECGF and Cox-2 showed that tumors with positive expression of both factors had a significantly lower AI and a significantly higher MVD than tumors with negative expression of both factors (P < 0.01).

CONCLUSION: Up-regulation of PD-ECGF and Cox-2 may facilitate tumor angiogenesis and inhibit apoptosis in gastric carcinoma, indicating cooperation between PD-ECGF and Cox-2 in gastric cancer, and therefore promote tumor growth and metastasis.