bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk Stratification of Colon Carcinogenesis through Enhanced Backscattering Spectroscopy Analysis of the Uninvolved Colonic Mucosa
Authors: Roy Hemant K. , Kim Young L. , Liu Yang , Wali Ramesh K. , Goldberg Michael J. , Turzhitsky Vladimir , Horwitz Jonathan , Backman Vadim
Published: March 2006

Introduction: Our group has been interested in applying advances in biomedical optics to colorectal cancer risk stratification. Through a recent technological breakthrough, we have been able to harness information from enhanced backscattering spectroscopy, an optics phenomenon that allows quantitative, depth-selective analysis of the epithelial microscale/nanoscale architecture. In the present study, we investigated the ability of enhanced backscattering analysis of the preneoplastic mucosa to predict risk of colon carcinogenesis.

Methods: Enhanced backscattering analysis was done on intestinal mucosa at preneoplastic time points from two experimental models of colorectal cancer: the azoxymethane-treated rat and the multiple intestinal neoplasia (MIN) mouse. Data were analyzed using two previously validated spectral markers: spectral slope and principle components. We then did a pilot study on mucosal biopsies from 63 subjects undergoing screening colonoscopy.

Results: In the azoxymethane-treated rat, when compared with saline-treated controls, significant changes in the enhanced backscattering markers were observed as early as 2 weeks after azoxymethane treatment (before the development of aberrant crypt foci and adenomas). Enhanced backscattering markers continued to progress over time in a manner consonant with future neoplasia. These data were replicated in the preneoplastic MIN mouse mucosa. In humans, spectral slopes in the endoscopically normal cecum, midtransverse colon, and rectum were markedly reduced in patients harboring adenomas when compared with those who were neoplasia free.

Conclusions: We show, for the first time, that enhanced backscattering analysis of an aliquot of uninvolved mucosa has the potential for predicting neoplastic risk throughout the colon in both experimental colorectal cancer models and humans.
An inducible short-hairpin RNA vector against osteopontin reduces metastatic potential of human esophageal squamous cell carcinoma in vitro and in vivo.
Authors: Ito Tetsuo , Hashimoto Yosuke , Tanaka Eiji , Kan Takatsugu , Tsunoda Shigeru , Sato Fumiaki , Higashiyama Motoshige , Okumura Tomoyuki , Shimada Yutaka
Published: March 2006

PURPOSE: To elucidate the clinical significance of osteopontin and the effect of conditional down-regulation of osteopontin in esophageal squamous cell carcinoma (ESCC), we investigated osteopontin expression in tumors and tested an inducible osteopontin-short-hairpin RNA (shRNA) expression vector in an ESCC cell line. EXPERIMENTAL DESIGN: Osteopontin mRNA expression was extracted from gene expression profiles of 23 tumors determined by cDNA microarray and was analyzed. Paraffin sections of 144 tumors were immunohistochemically investigated. Osteopontin protein expression in 34 cell lines was examined by Western blot. A doxycycline-inducible osteopontin-shRNA vector was stably transfected into HSA/c cells to assess the role of osteopontin in cell motility, invasion in vitro, tumor formation, and lymph node metastasis in nude mice. RESULTS: cDNA microarray revealed that high osteopontin mRNA expression was associated with poor survival of ESCC patients (P = 0.029). In immunohistochemistry, osteopontin protein expression was associated with poor prognosis (P < 0.001), distant lymph node metastasis (P = 0.0004), tumor staging (P = 0.027), and histologic grade (P = 0.024). Multivariate analysis showed that osteopontin overexpression was the strongest independent prognostic factor among nine clinicopathologic variables (P < 0.001). Among cell lines tested, 30 had overexpressed osteopontin protein compared with a normal esophageal epithelial cell line. An inducible shRNA vector against osteopontin successfully down-regulated osteopontin expression by 71% to 88% and repressed cell motility by 69% to 97%, cell invasion by 59% to 71%, tumor formation by 56% to 92%, and lymph node metastasis by 50% to 67% in HSA/c cells. CONCLUSIONS: Our findings suggest that osteopontin overexpression may play an important role in progression of ESCC and osteopontin could be a potential target of ESCC therapy.
Phase I Study of Low-Dose Interleukin-2, Fludarabine, and Cyclophosphamide for Previously Untreated Indolent Lymphoma and Chronic Lymphocytic Leukemia
Authors: Kasamon Yvette L. , Flinn Ian W. , Grever Michael R. , Diehl Louis F. , Garrett-Mayer Elizabeth , Goodman Steven N. , Lucas Margaret S. , Byrd John C.
Published: March 2006

Purpose: Fludarabine and cyclophosphamide is an effective combination but increases the risk of opportunistic infections due to depressed lymphocyte counts. In an attempt to preserve CD4 counts, we conducted a phase I, double-blind, placebo-controlled trial of recombinant interleukin-2 (IL-2) added to fludarabine and cyclophosphamide in patients with treatment-naive indolent lymphomas or chronic lymphocytic leukemia.

Experimental Design: Subcutaneous IL-2 (days 1-21 of each 28-day cycle) was combined with cyclophosphamide (600 mg/m2, day 8) and fludarabine (20 mg/m2, days 8-12) at four dose levels: 0.8, 1.0, 1.2, and 1.4 × 106 IU/m2/d. IL-2 dose was escalated in cohorts of four to six patients, with one patient per cohort receiving placebo.

Results: Twenty-three patients, median age 50, were enrolled, of whom 30% had chronic lymphocytic leukemia/small lymphocytic lymphoma and 52% had follicular lymphomas. The combination was generally well tolerated, with mainly hematologic toxicities. CD4 counts typically declined substantially during the early weeks of treatment and remained suppressed for months afterward. In the 18 evaluable patients who received IL-2, the mean absolute CD4 count was 999 cells/μL (range, 97-3,776) pretreatment, 379 cells/μL (range, 54-2,599) at day 14, and 98 cells/μL (range, 17-291) at end of treatment. In longitudinal linear models, the changes in CD4 counts were not significantly different across IL-2 dose levels.

Conclusions: The addition of low-dose IL-2 to fludarabine and cyclophosphamide does not seem immunoprotective. New approaches are needed to reduce the cellular immunosuppression and infectious complications associated with purine analogues.
The Putative Tumor Suppressor Cdx2 Is Overexpressed by Human Colorectal Adenocarcinomas
Authors: Witek Matthew E. , Nielsen Karl , Walters Rhonda , Hyslop Terry , Palazzo Juan , Schulz Stephanie , Waldman Scott A.
Published: March 2006

Purpose: The current paradigm suggests that the homeodomain transcription factor Cdx2, which directs the development and maintenance of the intestinal epithelium, is a tumor suppressor in the colon and rectum. Although a cardinal property of tumor suppressors is their inactivation during carcinogenesis, the expression of Cdx2 in colorectal tumors has not been compared with that in normal mucosa. Here, Cdx2 expression and function was quantified in tumors and matched normal mucosa from patients with colorectal cancer.

Experimental Design: Cdx2 expression was quantified by reverse transcription-PCR, immunoblot analysis, and immunohistochemistry. Transcriptional activity was explored by quantifying expression of an endogenous downstream target of Cdx2, guanylyl cyclase C (GCC), in tissues by quantitative reverse transcription-PCR and expression of exogenous Cdx2-specific luciferase promoter constructs in epithelial cells isolated from tumors and normal mucosa.

Results: Most (>80%) colorectal tumors overexpressed Cdx2 mRNA and protein compared with normal mucosa, with median fold increases of 3.6 and 1.4, respectively (P < 0.002). Concomitantly, immunohistochemistry revealed elevated levels of Cdx2 in nuclei of tumor cells compared with normal epithelial cells. Further, tumors exhibited increased expression of GCC compared with normal mucosa. Moreover, cells isolated from tumors overexpressed a Cdx2-specific luciferase promoter construct compared with normal mucosal cells.

Conclusion: These observations show, for the first time, the structural and functional overexpression of Cdx2 by human colorectal tumors compared with matched normal mucosa. They suggest that loss of Cdx2 expression or transcriptional activity is an infrequent event during tumorigenesis, which does not contribute to molecular mechanisms underlying initiation and progression of most colorectal tumors.
Increased antitumor activity, intratumor paclitaxel concentrations, and endothelial cell transport of cremophor-free, albumin-bound paclitaxel, ABI-007, compared with cremophor-based paclitaxel.
Authors: Desai Neil , Trieu Vuong , Yao Zhiwen , Louie Leslie , Ci Sherry , Yang Andrew , Tao Chunlin , De Tapas , Beals Bridget , Dykes Donald , Noker Patricia , Yao Rosie , Labao Elizabeth , Hawkins Michael , Soon-Shiong Patrick
Published: March 2006

ABI-007, an albumin-bound, 130-nm particle form of paclitaxel, was developed to avoid Cremophor/ethanol-associated toxicities in Cremophor-based paclitaxel (Taxol) and to exploit albumin receptor-mediated endothelial transport. We studied the antitumor activity, intratumoral paclitaxel accumulation, and endothelial transport for ABI-007 and Cremophor-based paclitaxel. Antitumor activity and mortality were assessed in nude mice bearing human tumor xenografts [lung (H522), breast (MX-1), ovarian (SK-OV-3), prostate (PC-3), and colon (HT29)] treated with ABI-007 or Cremophor-based paclitaxel. Intratumoral paclitaxel concentrations (MX-1-tumored mice) were compared for radiolabeled ABI-007 and Cremophor-based paclitaxel. In vitro endothelial transcytosis and Cremophor inhibition of paclitaxel binding to cells and albumin was compared for ABI-007 and Cremophor-based paclitaxel. Both ABI-007 and Cremophor-based paclitaxel caused tumor regression and prolonged survival; the order of sensitivity was lung > breast congruent with ovary > prostate > colon. The LD(50) and maximum tolerated dose for ABI-007 and Cremophor-based paclitaxel were 47 and 30 mg/kg/d and 30 and 13.4 mg/kg/d, respectively. At equitoxic dose, the ABI-007-treated groups showed more complete regressions, longer time to recurrence, longer doubling time, and prolonged survival. At equal dose, tumor paclitaxel area under the curve was 33% higher for ABI-007 versus Cremophor-based paclitaxel, indicating more effective intratumoral accumulation of ABI-007. Endothelial binding and transcytosis of paclitaxel were markedly higher for ABI-007 versus Cremophor-based paclitaxel, and this difference was abrogated by a known inhibitor of endothelial gp60 receptor/caveolar transport. In addition, Cremophor was found to inhibit binding of paclitaxel to endothelial cells and albumin. Enhanced endothelial cell binding and transcytosis for ABI-007 and inhibition by Cremophor in Cremophor-based paclitaxel may account in part for the greater efficacy and intratumor delivery of ABI-007.
Chemoprevention of Skin Carcinogenesis by Phenylretinamides: Retinoid Receptor–Independent Tumor Suppression
Authors: Xu Hui , Cheepala Satish , McCauley Elisabeth , Coombes Kevin , Xiao Lianchun , Fischer Susan M. , Clifford John L.
Published: March 2006

Fenretinide [N-(4-hydroxyphenyl)retinamide or 4-HPR] is a synthetic retinoid analogue with antitumor and chemopreventive activities. N-(4-Methoxyphenyl)retinamide (4-MPR) is the most abundant metabolite of 4-HPR detected in human serum following 4-HPR therapy. We have shown in in vitro studies that 4-HPR and 4-MPR can act independent of the classic nuclear retinoid receptor pathway and that 4-HPR, but not 4-MPR, can also activate nuclear retinoid receptors. In this study, we have compared the chemopreventive effects of topically applied 4-HPR and 4-MPR with the primary biologically active retinoid, all-trans retinoic acid (ATRA), in vivo in the mouse skin two-stage chemical carcinogenesis model. All three retinoids suppressed tumor formation but the effect of 4-HPR and 4-MPR, and not of ATRA, was sustained after their discontinuation. The tumor-suppressive effects of 4-HPR and 4-MPR were quantitatively and qualitatively similar, suggesting that the two may be acting through the same retinoid receptor–independent mechanism(s). We further explored this effect in vitro by analyzing primary cultures of mouse keratinocytes treated with the same retinoids. All three could induce apoptosis with a 48-hour treatment and only ATRA and 4-HPR induced an accumulation of cells in the G1 phase of the cell cycle. This finding is consistent with our previous results showing that the effects of phenylretinamides on the cell cycle are retinoid receptor dependent whereas apoptosis induction is not. A microarray-based comparison of gene expression profiles for mouse skin treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) alone and TPA + 4-HPR or TPA + 4-MPR reveals a high degree of coincidence between the genes regulated by the two phenylretinamides. We propose that 4-HPR may exert therapeutic and chemopreventive effects by acting primarily through a retinoid receptor–independent mechanism(s) and that 4-MPR may contribute to the therapeutic effect of 4-HPR by acting through the same retinoid receptor–independent mechanism(s).
Application of Oligonucleotide Microarrays to Assess the Biological Effects of Neoadjuvant Imatinib Mesylate Treatment for Localized Prostate Cancer
Authors: Febbo Phillip G. , Thorner Aaron , Rubin Mark A. , Loda Massimo , Kantoff Philip W. , Oh William K. , Golub Todd , George Daniel
Published: March 2006

Purpose: Neoadjuvant administration of antineoplastic therapies is used to rapidly assess the clinical and biological activity of novel systemic treatments. To assess the feasibility of using microarrays to assess molecular end points following targeted treatment in a heterogeneous tumor, we measured global gene expression in localized prostate cancer before and following neoadjuvant treatment with imatinib mesylate.

Patients and Methods: Patients with intermediate-risk to high-risk prostate cancer were treated for 6 weeks with 200 to 300 mg of oral imatinib mesylate. Frozen tissue was obtained from pretreatment ultrasound-guided biopsies and posttreatment radical prostatectomy specimens. Oligonucleotide microarray analysis following laser capture microdissection (LCM) and RNA amplification was used to assess gene expression changes associated with imatinib mesylate therapy. Immunohistochemistry was used to measure protein expression of MKP1 and CD31 and to assess cellular apoptosis.

Results: Of the 11 patients enrolled, high-quality microarray data was obtained from both biopsies (n = 7) and radical prostatectomy specimens (n = 9). Technically introduced intrasample gene expression variability was found to be significantly less than intertumor biological variability. Large gene expression differences were observed, and the gene with the most consistent differential expression (MKP1) was validated by immunohistochemistry. Gene set enrichment analysis suggests that imatinib mesylate therapy results in apoptosis of microvascular endothelial cells, an observation anecdotally supported by immunohistochemistry.

Conclusions: This study shows that high-quality microarray data can be generated using LCM and RNA amplification to discover potential mechanisms of targeted therapy in cancer.
Time to Detectable Metastatic Disease in Patients with Rising Prostate-Specific Antigen Values following Surgery or Radiation Therapy
Authors: Slovin Susan F. , Wilton Andrew S. , Heller Glenn , Scher Howard I.
Published: March 2006

Purpose: To determine factors associated with the development of radiographic metastatic progression for patients with recurrent prostate cancer following surgery and/or radiation therapy with prostate-specific antigen (PSA) doubling times of <12 months.

Experimental Design: One hundred and forty-eight patients with rising PSA values after primary therapy and a PSA doubling time of <12 months enrolled on clinical protocols were followed and monitored at protocol-specified intervals with examinations, PSA determinations, and imaging studies that included a computed tomography or magnetic resonance imaging and bone scan until metastases were detected. Metastasis-free survival was estimated using the Kaplan-Meier method and factors predictive of progression-free survival were estimated using the proportional hazards model. A nomogram based on the Cox model was constructed.

Results: Metastatic events were documented in 74% (110 of 148) of patients during the follow-up period. The median progression-free survival was 19 months, with 3- and 5-year metastatic progression–free survival of 32% and 16%, respectively. T stage (P = 0.07) and Gleason grade (P = 0.006) at the time of diagnosis, PSA values at the time of protocol entry (P < 0.001), and PSA doubling time (P < 0.001) were associated with progression in univariate analysis. These were combined into a nomogram to assess risk for an individual patient.

Conclusions: Tumor characteristics at the time of diagnosis, PSA doubling time following relapse, and the PSA value at the time of the protocol are predictive of metastatic progression. Because the PSA value at the time of monitoring was predictive, early treatment to prevent metastatic progression is favored.
Significance of skp2 expression in primary breast cancer.
Authors: Sonoda Hideto , Inoue Hiroshi , Ogawa Kazuhiko , Utsunomiya Tohru , Masuda Taka-aki , Mori Masaki
Published: March 2006

PURPOSE: We previously reported the p27 expression level to be an independent prognostic factor, and a high S-phase kinase-associated protein 2 (Skp2) expression level was significantly correlated with a poor prognosis in patients with gastric cancer. We herein examined the Skp2 expression in breast cancer and attempted to identify any associations between the Skp2 expression status and either the clinicopathologic variables or the patient's prognosis. EXPERIMENTAL DESIGN: We established four Skp2-transfected breast cancer cell lines and assessed the correlations between the Skp2 and p27 expressions using real-time reverse transcription-PCR and a Western blot analysis. We then analyzed the clinicopathologic significance of Skp2 mRNA expression in 169 Japanese patients with breast cancer. An immunohistochemical analysis was also done. RESULTS: The p27 protein expression markedly decreased after Skp2 transfection, whereas no alteration in the p27 mRNA expression was observed. The Skp2 protein expression level as determined by immunohistochemical staining thus showed a significant correlation with the Skp2 mRNA expression (P = 0.001) and a significant inverse correlation with the p27 protein expression (P = 0.042). The patients with a high Skp2 gene expression were significantly younger than those with a low expression (P = 0.002). The prognosis of patients with a high Skp2 expression was significantly (P = 0.022) poorer than for those with a low expression. Moreover, a high expression of Skp2 was an independent variable that correlated with a shorter disease-free survival (relative risk, 3.33; 95% confidence interval, 1.296-8.578; P = 0.013). CONCLUSIONS: The present results suggest that Skp2 may play an important role particularly in young breast cancer, and it is also considered to have strong independent prognostic potential and thus may prove to be a useful target for the treatment of breast cancer.
The GNAS1 T393C Polymorphism Predicts Survival in Patients with Clear Cell Renal Cell Carcinoma
Authors: Frey Ulrich H. , Lümmen Gerd , Jäger Tobias , Jöckel Karl-Heinz , Schmid Kurt W. , Rübben Herbert , Müller Norbert , Siffert Winfried , Eisenhardt Andreas
Published: March 2006

Purpose: G proteins mediate signaling from cell surface receptors to specific intracellular proteins. In vitro cancer cell line studies revealed a link between the Gαs protein and proapoptotic processes. We have recently shown that TT genotypes of the GNAS1 T393C polymorphism display increased transcription of Gαs and a more favorable clinical course in bladder and colorectal cancer patients compared both with TC or CC genotypes.

Experimental Design: In the present study, 150 patients with clear cell renal cell carcinoma surgically treated by nephrectomy with curative intent were retrospectively genotyped to elucidate a potential association between T393C genotypes and clinical outcome.

Results: The C-allele frequency in the renal cell carcinoma patient group was 0.51, which is not significantly different from that of a healthy blood donor group. Kaplan-Meier curves for tumor progression, development of metastasis, and tumor-related death showed a significant association of the T393C polymorphism with outcome (5-year cancer-specific survival rates: TT, 91%; TC, 81%; CC, 69%; P = 0.015). Multivariate Cox proportional analysis of a 10-year follow-up confirmed the T393C polymorphism as an independent prognostic factor in clear cell renal cell carcinoma. Homozygous CC patients were at highest risk for progression (hazard ratio, 2.48; P = 0.009) or tumor-related death (hazard ratio, 3.15; P = 0.018) compared with T-allele carriers.

Conclusion: Our results show that besides tumor stage, lymph node status, and tumor grade, the GNAS1 T393C status is a novel independent host factor for disease progression in patients with clear cell renal cell carcinoma and provides further evidence for the T393C polymorphism as a general prognostic tumor marker.
Focal Adhesion Kinase Silencing Augments Docetaxel-Mediated Apoptosis in Ovarian Cancer Cells
Authors: Halder Jyotsnabaran , Landen Charles N. , Lutgendorf Susan K. , Li Yang , Jennings Nicholas B. , Fan Dominic , Nelkin Gina M. , Schmandt Rosemarie , Schaller Michael D. , Sood Anil K.
Published: March 2006

Objective: Docetaxel causes cell death through induction of apoptosis; however, cell death characteristics for docetaxel have not yet been fully elucidated. We examined the role of focal adhesion kinase (FAK) cleavage in docetaxel-mediated apoptosis.

Methods: FAK degradation after treatment with docetaxel was determined in both taxane-sensitive (HeyA8 and SKOV3) and taxane-resistant (HeyA8-MDR and SKOV3-TR) ovarian cancer cell lines by Western blot analysis. Cell growth was determined with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. FAK-targeting small interfering RNA (siRNA) was used to decrease FAK expression. Apoptosis and caspase activity were determined using commercially available kits.

Results: SKOV3 and HeyA8 cell lines were both sensitive to docetaxel (IC50 levels, 1-6.2 nmol/L), whereas the SKOV3-TR and HeyA8-MDR cells were resistant (IC50 ≥ 250 nmol/L for both). Docetaxel induced high rates of apoptosis in SKOV3 and HeyA8 cells (84% and 66% apoptosis, respectively) but minimal apoptosis (5-8%) in SKOV3-TR and HeyA8-MDR cells. Similarly, FAK was cleaved in SKOV3 and HeyA8 cells in response to docetaxel treatment but unchanged in the resistant cells. Caspase-3 and caspase-8 activity also increased significantly in docetaxel-treated SKOV3 and HeyA8 cells but not in the taxane-resistant cells. DEVD-fmk (caspase-3 blocker) was able to block both FAK cleavage and apoptosis mediated by docetaxel in SKOV3 and HeyA8 cells. FAK siRNA transfection resulted in 70% to 90% decrease in FAK levels in all cell lines within 72 hours. FAK silencing augmented docetaxel-mediated growth inhibition (5- to 8-fold increase) and apoptosis in both of the taxane-sensitive and taxane-resistant cell lines.

Conclusions: Docetaxel induces FAK cleavage, mediated through activation of caspase-3, in taxane-sensitive ovarian cancer cells but not in taxane-resistant cells. The absence of FAK degradation may contribute to cell survival in taxane-resistant cells. FAK silencing promotes the in vitro efficacy of docetaxel in both taxane-sensitive and taxane-resistant cell lines and may serve as a novel therapeutic approach.
Inhibitors of Raf Kinase Activity Block Growth of Thyroid Cancer Cells with RET/PTC or BRAF Mutations In vitro and In vivo
Authors: Ouyang Bin , Knauf Jeffrey A. , Smith Eric P. , Zhang Lei , Ramsey Tim , Yusuff Naeem , Batt David , Fagin James A.
Published: March 2006

Purpose: Papillary thyroid carcinomas are associated with nonoverlapping activating mutations of RET, NTRK, RAS and BRAF, which altogether are present in ∼70% of cases. We postulated that compounds that inhibit a distal effector in the mitogen-activated protein kinase (MAPK) pathway would inhibit growth and tumorigenicity of human thyroid cancer cell lines with mutations of RET or BRAF.

Experimental Design and Results: We first examined the effects of AAL-881 and LBT-613, two inhibitors of RAF kinase activity, on RAF-MAPK/extracellular signal–regulated kinase (ERK) kinase (MEK)-ERK activation in thyroid PCCL3 cells after conditional induction of expression of H-RASG12V or BRAFV600E. Both compounds blocked RAS and RAF-dependent MEK and ERK phosphorylation. They also potently blocked MEK phosphorylation in human thyroid cancer cell lines with either RET/PTC1 (TPC1) or BRAFV600E (NPA, ARO, and FRO) mutations. Inhibition of ERK phosphorylation was transient in TPC1 and ARO cells, with recovery of ERK phosphorylation associated with concomitant down-regulation of the MAPK phosphatases MKP-3 and DUSP5. Both compounds inhibited growth of all cell lines, with LBT-613 being ∼10-fold more potent than AAL-881. TPC1 cells were more sensitive to growth inhibition (IC50 0.1-0.25 and ∼0.05 μmol/L for AAL-881 and LBT-613, respectively) than BRAF (+) lines (IC50 2.5-5 and 0.1-0.5 μmol/L, respectively). Growth inhibition was associated with G1 arrest, and induction of cell death. Growth of ARO and NPA tumor xenografts was inhibited by LBT-613 or AAL-881. MEK and ERK phosphorylation was inhibited by both compounds in ARO but not in NPA cell xenografts.

Conclusions: Compounds that inhibit kinase activity are effective growth inhibitors for poorly differentiated thyroid cancer cell lines with either RET or RAF mutations, and hold promise for treatment of most forms of papillary thyroid carcinoma.
Long-term Clinical Outcome of Phase IIb Clinical Trial of Percutaneous Injection with Holmium-166/Chitosan Complex (Milican) for the Treatment of Small Hepatocellular Carcinoma
Authors: Kim Ja Kyung , Han Kwang-Hyub , Lee Jong Tae , Paik Yong Han , Ahn Sang Hoon , Lee Jong Doo , Lee Kwan Sik , Chon Chae Yoon , Moon Young Myoung
Published: March 2006

Purpose: The purpose of this study was to evaluate the long-term tumor response after phase IIb clinical study and the safety of percutaneous holmium-166 (166Ho)/chitosan complex injection (PHI) therapy for small hepatocellular carcinoma as a local ablative treatment. 166Ho is a radioactive isotope derived from natural holmium-165. We developed a 166Ho/chitosan complex (Milican, Dong Wha Pharmaceutical Co., Seoul, Korea) using chitosan as a vehicle to retain the radioactive material within the tumor.

Experimental Design: Forty patients with single hepatocellular carcinoma <3 cm in maximal diameter were enrolled in this study. The patients either had refused surgery or were poor surgical candidates and were treated with only single session of PHI.

Results: Two months after PHI, complete tumor necrosis was achieved in 31 of 40 patients (77.5%) with hepatocellular carcinoma lesions <3 cm and in 11 of 12 patients (91.7%) with hepatocellular carcinoma <2 cm. Tumors recurred in 28 patients during the long-term follow-up period, of which 24 recurred at another intrahepatic site. The 1-year and 2-year cumulative local recurrence rates were 18.5% and 34.9%, respectively. The survival rates at 1, 2, and 3 years were 87.2%, 71.8%, and 65.3%, respectively. Transient bone marrow depression was serious adverse event requiring hospitalization in two patients.

Conclusions: PHI was found to be a safe and novel local ablative procedure for the treatment of small hepatocellular carcinoma and could be used as a bridge to transplantation. A phase III randomized active control trial is clearly warranted among a larger study population.
Dual Promoter–Controlled Oncolytic Adenovirus CG5757 Has Strong Tumor Selectivity and Significant Antitumor Efficacy in Preclinical Models
Authors: Li Yuanhao , Idamakanti Neeraja , Arroyo Trini , Thorne Steve , Reid Tony , Nichols Scott , VanRoey Melinda , Colbern Gail , Nguyen Natalie , Tam Orlena , Working Peter , Yu De-Chao
Published: March 2006

Purpose: Transcriptionally controlled oncolytic adenovirus CG5757 is engineered with two tumor-specific promoters from E2F-1 and human telomerase reverse transcriptase genes. This virus has broad anticancer spectrum and higher specificity. The objective of the current study is to show its antitumor selectivity and therapeutic potential.

Experimental Design: The antitumor specificity of E2F-1 and human telomerase reverse transcriptase promoters was evaluated in a panel of tumor and normal cells. Under the control of these promoters, the tumor-selective expression of E1a and E1b genes was evaluated. Further in vitro antitumor specificity and potency of this virus were characterized by viral replication and cytotoxicity assays followed by a newly developed ex vivo tumor culture assay. Subsequently, in vivo antitumor efficacy and toxicology studies were carried out to assess the therapeutic potential of this oncolytic agent.

Results: In a broad panel of cells, E2F-1 and human telomerase reverse transcriptase promoters were activated in a tumor-selective manner. Under the control of these promoters, expression of E1a and E1b genes appears only in tumor cells. This specificity is extended to viral replication and hence the cytotoxicity in a broad range of cancer cells. Furthermore, CG5757 only replicates in cancer tissues but not in normal tissues that are derived from clinical biopsies. The safety profile was further confirmed in in vivo toxicology studies, and strong efficacy was documented in several tumor xenograft models after CG5757 was given via different routes and regimens.

Conclusions: CG5757 has strong antitumor selectivity and potency. It has low toxicity and has great potential as a therapeutic agent for different types of cancers.
Combination Chemotherapy and Radiation of Human Squamous Cell Carcinoma of the Head and Neck Augments CTL-Mediated Lysis
Authors: Gelbard Alexander , Garnett Charlie T. , Abrams Scott I. , Patel Vyomesh , Gutkind J. Silvio , Palena Claudia , Tsang Kwong-Yok , Schlom Jeffrey , Hodge James W.
Published: March 2006

Purpose: The combination of systemic multiagent chemotherapy (5-fluorouracil + cisplatin) and tumor irradiation is standard of care for head and neck squamous cell carcinoma (HNSCC). Furthermore, it has been shown that sublethal doses of radiation or chemotherapeutic drugs in diverse cancer types may alter the phenotype or biology of neoplastic cells, making them more susceptible to CTL-mediated cytotoxicity. However, little is known about the potential synergistic effect of drug plus radiation on CTL killing. Here, we examined whether the combination of two chemotherapeutics and ionizing radiation enhanced CTL-mediated destruction of HNSCC more so than either modality separately, as well as the basis for the enhanced tumor cell lysis.

Experimental Design: Several HNSCC cell lines with distinct biological features were treated with sublethal doses of cisplatin and 5-fluorouracil for 24 hours and with 10-Gy irradiation. Seventy-two hours postirradiation, tumor cells were exposed to an antigen-specific CD8+ CTL directed against carcinoembryonic antigen or MUC-1.

Results: In three of three tumor cell lines tested, enhanced CTL activity was observed when the two modalities (chemotherapy and radiation) were combined as compared with target cells exposed to either modality separately. CTL-mediated lysis was MHC restricted and antigen specific and occurred almost entirely via the perforin pathway. Moreover, the combination treatment regimen led to a 50% reduction in Bcl-2 expression whereas single modality treatment had little bearing on the expression of this antiapoptotic gene.

Conclusions: Overall, these results reveal that (a) CTL killing can be enhanced by combining multiagent chemotherapy and radiation and (b) combination treatment enhanced or sensitized HNSCC to the perforin pathway, perhaps by down-regulating Bcl-2 expression. These studies thus form the rational basis for clinical trials of immunotherapy concomitant with the current standard of care of HNSCC.
Expression of Interleukin-18 and Caspase-1 in Cutaneous T-Cell Lymphoma
Authors: Yamanaka Kei-ichi , Clark Rachael , Dowgiert Rebecca , Hurwitz Daniel , Shibata Michio , Rich Benjamin E. , Hirahara Kazuki , Jones David A. , Eapen Sara , Mizutani Hitoshi , Kupper Thomas S.
Published: March 2006

Purpose: Cutaneous T-cell lymphoma (CTCL) is a malignancy of skin-homing Th2 T cells. Clonal T cells and CTCL skin lesions typically express Th2 cytokines, including interleukin (IL)-4, IL-5, and IL-10, but fail to produce Th1 cytokines. However, the reason for Th2 bias is unknown. IL-18 is a pleiotropic proinflammatory cytokine produced by monocytes/macrophages lineage as well as epithelial cells, such as human keratinocytes. In the absence of IL-12, IL-18 leads to increased immunoglobulin E production from B cells and enhanced production of IL-4 and IL-13 by basophils, mast cells, and CD4+ T cells. We have analyzed cytokines in CTCL patients, which may bias the immune response around the Th1/Th2 axis.

Experimental Design: We examined plasma of 95 CTCL patients and skin of 20 CTCL patients for IL-18, caspase-1, IL-12, and other cytokines. To identify the presence or absence of these cytokine proteins in CTCL and normal skin, we cultured explants from skin biopsies on three-dimensional matrices.

Results: Plasma levels of IL-18 and its converting enzyme, caspase-1, were significantly elevated in CTCL. mRNA levels for these factors were also elevated in CTCL skin lesions. Matrices populated with CTCL lesional skin produced significant amounts of IL-18 and caspase-1; however, production of IL-12 protein was barely detectable.

Conclusions: We propose that the high levels of IL-18 expression in lesional CTCL skin contribute to increased plasma levels of IL-18 and that this, in the face of significantly lower levels of IL-12, may contribute to the Th2 bias seen in this disease.
Kinetics of Metastatic Breast Cancer Cell Trafficking in Bone
Authors: Phadke Pushkar A. , Mercer Robyn R. , Harms John F. , Jia Yujiang , Frost Andra R. , Jewell Jennifer L. , Bussard Karen M. , Nelson Shakira , Moore Cynthia , Kappes John C. , Gay Carol V. , Mastro Andrea M. , Welch Danny R.
Published: March 2006

Purpose: In vivo studies have focused on the latter stages of the bone metastatic process (osteolysis), whereas little is known about earlier events, e.g., arrival, localization, and initial colonization. Defining these initial steps may potentially identify the critical points susceptible to therapeutic intervention.

Experimental Design: MDA-MB-435 human breast cancer cells engineered with green fluorescent protein were injected into the cardiac left ventricle of athymic mice. Femurs were analyzed by fluorescence microscopy, immunohistochemistry, real-time PCR, flow cytometry, and histomorphometry at times ranging from 1 hour to 6 weeks.

Results: Single cells were found in distal metaphyses at 1 hour postinjection and remained as single cells up to 72 hours. Diaphyseal arrest occurred rarely and few cells remained there after 24 hours. At 1 week, numerous foci (2-10 cells) were observed, mostly adjacent to osteoblast-like cells. By 2 weeks, fewer but larger foci (≥50 cells) were seen. Most bones had a single large mass at 4 weeks (originating from a colony or coalescing foci) which extended into the diaphysis by 4 to 6 weeks. Little change (<20%) in osteoblast or osteoclast numbers was observed at 2 weeks, but at 4 to 6 weeks, osteoblasts were dramatically reduced (8% of control), whereas osteoclasts were reduced modestly (to ∼60% of control).

Conclusions: Early arrest in metaphysis and minimal retention in diaphysis highlight the importance of the local milieu in determining metastatic potential. These results extend the Seed and Soil hypothesis by demonstrating both intertissue and intratissue differences governing metastatic location. Ours is the first in vivo evidence that tumor cells influence not only osteoclasts, as widely believed, but also eliminate functional osteoblasts, thereby restructuring the bone microenvironment to favor osteolysis. The data may also explain why patients receiving bisphosphonates fail to heal bone despite inhibiting resorption, implying that concurrent strategies that restore osteoblast function are needed to effectively treat osteolytic bone metastases.
Two Drug Interaction Studies Evaluating the Pharmacokinetics and Toxicity of Pemetrexed When Coadministered with Aspirin or Ibuprofen in Patients with Advanced Cancer
Authors: Sweeney Christopher J. , Takimoto Chris H. , Latz Jane E. , Baker Sharyn D. , Murry Daryl J. , Krull James H. , Fife Karen , Battiato Linda , Cleverly Ann , Chaudhary Ajai K. , Chaudhuri Tuhin , Sandler Alan , Mita Alain C. , Rowinsky Eric K.
Published: March 2006

Purpose: Pemetrexed is an antimetabolite that is structurally similar to methotrexate. Because nonsteroidal anti-inflammatory drugs (NSAID) impair methotrexate clearance and increase its toxicity, we evaluated the pharmacokinetics and toxicity of pemetrexed when coadministered with aspirin or ibuprofen in advanced cancer patients.

Experimental Design: In two independent, randomized, crossover drug interaction studies, cancer patients with a creatinine clearance (CrCl) ≥60 mL/min received an NSAID (aspirin or ibuprofen) with either the first or the second dose of pemetrexed (cycle 1 or 2). Pemetrexed (500 mg/m2) was infused i.v. on day 1 of a 21-day cycle, and all patients were supplemented with oral folic acid and i.m. vitamin B12. Aspirin (325 mg) or ibuprofen (400 mg; 2 × 200 mg) was given orally every 6 hours, starting 2 days before pemetrexed administration, with the ninth and final dose taken 1 hour before infusion. Pemetrexed pharmacokinetics with and without concomitant NSAID treatment were compared for cycles 1 and 2.

Results: Data from 27 patients in each study were evaluable for the analysis of pemetrexed pharmacokinetics. Coadministration of aspirin did not alter pemetrexed pharmacokinetics; however, ibuprofen coadministration was associated with a 16% reduction in clearance, a 15% increase in maximum plasma concentration, and a 20% increase in area under the plasma concentration versus time curve but no significant change in Vss compared with pemetrexed alone. No febrile neutropenia occurred in any patient, and no increase in pemetrexed-related toxicity was associated with NSAID administration.

Conclusions: Pemetrexed (500 mg/m2) with vitamin supplementation is well tolerated and requires no dosage adjustment when coadministered with aspirin (in patients with CrCl ≥60 mL/min) or ibuprofen (in patients with CrCl ≥80 mL/min).
Prostate-Specific Antigen Modulates Genes Involved in Bone Remodeling and Induces Osteoblast Differentiation of Human Osteosarcoma Cell Line SaOS-2
Authors: Nadiminty Nagalakshmi , Lou Wei , Lee Soo Ok , Mehraein-Ghomi Farideh , Kirk Jason S. , Conroy Jeffrey M. , Zhang Haitao , Gao Allen C.
Published: March 2006

Purpose: The high prevalence of osteoblastic bone metastases in prostate cancer involves the production of osteoblast-stimulating factors by prostate cancer cells. Prostate-specific antigen (PSA) is a serine protease uniquely produced by prostate cancer cells and is an important serologic marker for prostate cancer. In this study, we examined the role of PSA in the induction of osteoblast differentiation.

Experimental Design: Human cDNA containing a coding region for PSA was transfected into human osteosarcoma SaOS-2 cells. SaOS-2 cells were also treated with exogenously added PSA. We evaluated changes in global gene expression using cDNA arrays and Northern blot analysis resulting from expression of PSA in human osteosarcoma SaOS-2 cells.

Results: SaOS-2 cells expressing PSA had markedly up-regulated expression of genes associated with osteoblast differentiation including runx-2 and osteocalcin compared with the controls. Consistent with these results, the stable clones expressing PSA showed increased mineralization and increased activity of alkaline phosphatase in vitro compared with controls, suggesting that these cells undergo osteoblast differentiation. We also found that osteoprotegerin expression was down-regulated and that the receptor activator of NF-κB ligand expression was up-regulated in cells expressing PSA compared with controls.

Conclusions: Modulation of the expression of osteogenic genes and alteration of the balance between osteoprotegerin–receptor activator of NF-κB ligand by PSA suggests that PSA produced by metastatic prostate cancer cells may participate in bone remodeling in favor of the development of osteoblastic metastases in the heterogeneous mixture of osteolytic and osteoblastic lesions. These findings provide a molecular basis for understanding the high prevalence of osteoblastic bone metastases in prostate cancer.
Prognostic Value of Tumor-Infiltrating CD4+ T-Cell Subpopulations in Head and Neck Cancers
Authors: Badoual Cécile , Hans Stéphane , Rodriguez José , Peyrard Severine , Klein Christophe , Agueznay Nour El Houda , Mosseri Véronique , Laccourreye Ollivier , Bruneval Patrick , Fridman Wolf H. , Brasnu Daniel F. , Tartour Eric
Published: March 2006

Purpose: CD4+ T cells play a central role in initiating and maintaining anticancer immune responses. However, regulatory CD4+CD25+ T cells which express Foxp3 have also been shown to inhibit antitumor effector T cells. In view of these heterogeneous CD4+ T-cell populations, this study was designed to determine the prognostic value of various tumor-infiltrating CD4+ T-cell populations in head and neck squamous cell carcinoma.

Experimental Design: Eighty-four newly diagnosed untreated patients with histologically proven primary head and neck squamous cell carcinoma were included in this study. Double or triple immunofluorescence staining was done to assess and quantify the activated CD4+CD69+ T cells, regulatory CD4+Foxp3+ T cells, and mixed CD4+CD25+ T cells comprising both activated and regulatory T cells.

Results: On univariate analysis, high levels of tumor-infiltrating CD4+CD69+ T cells were correlated with both better locoregional control (P = 0.01) and longer survival (P = 0.01). Infiltration by regulatory Foxp3+CD4+ T cells was positively associated with a better locoregional control of the tumor. Multivariate analysis showed that the only significant prognostic factors related to locoregional control were T stage (P = 0.02) and CD4+Foxp3+ T-cell infiltration of the tumor (P = 0.02). In the Cox multivariate analysis, only two variables influenced overall survival probability: T stage (P = 0.036) and CD4+CD69+ T-cell infiltration (P = 0.017).

Conclusion: This study shows that tumor-infiltrating activated CD4+CD69+ T cells are associated with a good prognosis in head and neck squamous cell carcinoma. In addition, regulatory Foxp3+CD4+ T cells are positively correlated with locoregional control may be through down-regulation of harmful inflammatory reaction, which could favor tumor progression.
Delta-24 Increases the Expression and Activity of Topoisomerase I and Enhances the Antiglioma Effect of Irinotecan
Authors: Gomez-Manzano Candelaria , Alonso Marta M. , Yung W.K. Alfred , McCormick Frank , Curiel David T. , Lang Frederick F. , Jiang Hong , Bekele B. Nebiyou , Zhou Xian , Alemany Ramon , Fueyo Juan
Published: March 2006

Purpose: In this study, we sought to determine whether Delta-24 could sensitize glioma cells to the topoisomerase I inhibitor irinotecan (CPT-11) and to identify the mechanisms underlying this enhanced anticancer effect.

Experimental Design: We used human glioblastoma cell lines for the in vitro studies. The expression of topoisomerase I was determined in Western blot analyses, and topoisomerase I activity was determined by measuring the relaxation of a supercoiled DNA. The cell cycle distribution of cells was determined by flow cytometry analysis of the cellular DNA content. Cell viability was quantified by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Tissue culture infection dose assays were used to quantitate adenovirus replication. For the in vivo studies, athymic mice received intracranial/intratumoral injections of Delta-24 in combination with CPT-11, after which animal survival was monitored.

Results: Delta-24 infection caused human glioma cells to accumulate in the S phase and induced the expression and activity of topoisomerase I as shown by Western blot and in vitro enzymatic activity assays. Further, we showed that the sequential administration of Delta-24 and CPT-11 to human glioma cell cultures potentiated the CPT-11-mediated anticancer effect in vitro without modifying the replicative phenotype of the oncolytic adenovirus. In vivo experiments showed that the single intratumoral administration of Delta-24 to intracranially implanted human glioma xenografts followed by the systemic administration of CPT-11 resulted in significantly prolonged animal survival.

Conclusions: The combination of Delta-24 treatment with CPT-11 showed an enhanced anticancer effect, which suggests that the interaction between adenoviral and human proteins can be exploited in rational anticancer therapies comprising replication-competent adenoviruses and conventional chemotherapeutic agents.
In vitroStimulation of CD8 and CD4 T Cells by Dendritic Cells Loaded with a Complex of Cholesterol-Bearing Hydrophobized Pullulan and NY-ESO-1 Protein: Identification of a New HLA-DR15–Binding CD4 T-Cell Epitope
Authors: Hasegawa Kosei , Noguchi Yuji , Koizumi Fumihito , Uenaka Akiko , Tanaka Motoyuki , Shimono Michihide , Nakamura Hideo , Shiku Hiroshi , Gnjatic Sacha , Murphy Roger , Hiramatsu Yuji , Old Lloyd J. , Nakayama Eiichi
Published: March 2006

Purpose: NY-ESO-1 belongs to a class of cancer/testis antigens and has been shown to be immunogenic in cancer patients. We synthesized a complex of cholesterol-bearing hydrophobized pullulan and NY-ESO-1 protein (CHP/ESO) and investigated the in vitro stimulation of CD8 and CD4 T cells from peripheral blood mononuclear cells in healthy donors with autologous CHP/ESO-loaded dendritic cells as antigen-presenting cells.

Experimental Design: In vitro stimulation of CD8 or CD4 T cells was determined by IFNγ ELISPOT assays against autologous EBV-B cells infected with vaccinia/NY-ESO-1 recombinant virus or wild-type vaccinia virus as targets and by ELISA measuring secreted IFNγ.

Results: NY-ESO-1–specific CD8 and CD4 T cells were induced. In a donor expressing HLA-A2, CD8 T cells stimulated with CHP/ESO-loaded dendritic cells recognized naturally processed NY-ESO-1157-165, an HLA-A2–binding CD8 T cell epitope. NY-ESO-1 CD4 T cells were Th1-type. We identified a new HLA-DR15–binding CD4 T cell epitope, NY-ESO-137-50.

Conclusions: These findings indicate that CHP/ESO is a promising polyvalent cancer vaccine targeting NY-ESO-1.