Spontaneous tumor-specific humoral and cellular immune responses to NY-ESO-1 in hepatocellular carcinoma.

PURPOSE: Hepatocellular carcinoma (HCC) is the fifth most common cancer around the world. Although several therapeutic approaches for treatment of HCC are available, survival rates for HCC patients are still very poor because of inefficient treatment options. For HCC, as well as other tumors, antigen-specific immunotherapy remains a viable approach that is dependent on the definition of tumor-associated antigens. NY-ESO-1, a member of the cancer testis antigen family, is one possible candidate for a tumor-specific antigen in HCC. The aim of this study was to show the relevance of NY-ESO-1 in hepatocellular carcinoma. EXPERIMENTAL DESIGN: Sera samples from 189 HCC patients were analyzed for NY-ESO-1-specific antibodies. Forty-nine HCC patients were screened for NY-ESO-1 mRNA expression in HCC tissue. Selected patients were followed for up to 3 years to correlate their immune response with their clinical course of events. NY-ESO-1-specific CD4+ and CD8+ T-cell responses from NY-ESO-1 seropositive patients were analyzed and a NY-ESO-1+ specific cytotoxic T-cell line was generated. RESULTS: Twelve of 49 analyzed tumor samples expressed NY-ESO-1 mRNA and 23 of 189 patients showed NY-ESO-1-specific antibody responses. These humoral immune responses were accompanied by NY-ESO-1-specific functional CD4+ and CD8+ T-cell responses. Finally, NY-ESO-1 humoral responses were dependent on the presence of NY-ESO-1-expressing tumors. CONCLUSIONS: This is the first report of a spontaneous immune response in HCC patients to a known tumor-specific antigen, NY-ESO-1 protein. Our data favor the possibility of immunotherapeutic strategies for the treatment of HCC.     

Whole body 18FDG-PET and the response of esophageal cancer to induction therapy: results of a prospective trial.

PURPOSE: Whole-body 18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) imaging before and after induction therapy was prospectively evaluated in patients with esophageal cancer to determine whether changes in PET images could measure response to therapy. PATIENTS AND METHODS: Between April 1997 and April 1999, 39 patients (34 men and five women; median age, 59 years; range, 36 to 76 years) with esophageal cancer were prospectively enrolled in a single-institution clinical trial of staging, including PET, induction therapy, restaging including PET, and esophagectomy. All patients undergoing esophagectomy after induction therapy (n = 17) were followed either to recurrence, to death, or through a disease-free interval of at least 24 months. RESULTS: PET after standard staging studies and before therapy imaged undetected sites of metastatic disease in six patients (15%). Restaging (including PET) after induction therapy did not identify any patients with disease progression or any patients with loco-regionally unresectable disease at exploration. The median decrease in the standardized uptake value (SUV) during induction therapy was 59%. After R0 esophagectomy, the 2-year disease-free and overall survival was 38% and 63%, respectively, among patients who had a less than 60% decrease in SUV, and 67% and 89%, respectively, among patients who had a greater than 60% decrease in SUV (P =.055 and P =.088, respectively). CONCLUSION: Compared with conventional imaging, PET detects additional sites of metastatic disease at initial evaluation. After induction therapy, PET did not add to the estimation of loco-regional resectability and did not detect new distant metastases. However, changes in [18F]FDG PET may predict disease-free and overall survival after induction therapy and resection in patients with esophageal cancer. Further evaluation in larger trials is warranted.     

Sputum cytological atypia as a predictor of incident lung cancer in a cohort of heavy smokers with airflow obstruction.

Individuals with cytological atypia in sputum may be at increased risk for lung cancer. We conducted a longitudinal analysis of the association between lung cancer incidence and cytological atypia in sputum samples collected prospectively from an ongoing cohort of adults at high risk for lung cancer. Cohort members had a smoking history of > or = 30 pack-years and chronic obstructive pulmonary disease documented by pulmonary airflow testing. Sputum samples collected at baseline and periodically thereafter were examined by standard cytological methods. From the cohort of 2,006 people, there were 83 incident lung cancers over 4,469 person-years of observation. At baseline, the association between personal and behavioral characteristics, and sputum cytological atypia was assessed by multiple logistic regression. The association between sputum cytological atypia and incident lung cancer was then assessed by hazard ratios using proportional hazards regression analysis, adjusting for potential confounding factors. Cytological atypia graded as moderate or worse was associated with continuing cigarette smoking (adjusted odds ratio, 2.5; 95% confidence interval, 1.5-4.1), and with lower levels of intake of fruits and vegetables (P for trend = 0.04). Atypia was not associated with several other factors, including the degree of airflow obstruction, the use of vitamin supplements, nonsteroidal anti-inflammatory drugs, or metered-dose steroid inhalers. Incident lung cancer was increased among those with moderate or worse cytological atypia (adjusted hazards ratio, 2.8; 95% confidence interval, 1.4-5.5). This association was not confounded by other risk factors. We conclude that in this high-risk cohort, cytological atypia is associated with continuing smoking and low intake of fruits and vegetables, but that independent of these and other factors, the risk of incident lung cancer is increased among those with moderate or worse grades of cytological atypia in their sputum.     

The antiproliferative action of a melphalan hexapeptide with collagenase-cleavable site

Purpose: The objective of the present study was to examine the relevance of collagenase in the antitumor action of a melphalan peptide (MHP) with a collagenase-cleavable sequence. The question was addressed as to whether collagenase may act as an activator or a target in the antiproliferative mechanism of MHP. Methods: Melphalan was inserted into peptides representing the sequence Pro-Gln-Gly-Ile-Ala.Gly of the collagenase-cleavable site in collagens. Changes in growth and collagenase IV activities of HT-1080, HT-29, HT-168, and MCF-7 cell cultures were investigated. Results: The present investigations provide data indicating that Pro-Gln-Gly-Ile-Mel-Gly (melphalan hexapeptide, MHP) is a substrate for both bacterial and 72-kDa type IV collagenases and that in this way it can generate Ile-Mel-Gly (melphalan tripeptide, MTP) of higher cytotoxic potency. Indeed, the formation of MTP was detected in the conditioned medium of HT-1080, a collagenase IV-producing human fibrosarcoma. In a comparison of equimolar concentrations of melphalan and its two peptide derivatives (MHP and MTP), superior antiproliferative action of MTP was seen in HT-29, HT-1080, and HT-168 tumor cell cultures. However, the relatively modest cytostatic actions of MHP were increased when bacterial collagenase was added to the cell cultures. After melphalan treatment, reduced levels of both 92 and 72-kDa type IV collagenases were seen in the HT-1080 cell cultures. However, the reduction of collagenase activity and the cell counts did not run parallel in the MTP- or MHP-treated cultures; indeed, collagenase activity related to cell numbers showed an elevated level. Conclusions: As the conversion of MHP to the more toxic MTP was detected in the presence of collagenases, it is possible that collagenase-directed activation of prodrugs may be a promising approach for the development of more selective cytostatic drugs against malignant tumors with high collagenase activities. Received: 6 October 1996 / Accepted: 22 July 1997     

Lithocholic acid decreases expression of UGT2B7 in Caco-2 cells: a potential role for a negative farnesoid X receptor response element.

Human UDP-glucuronosyltransferase (UGT) 2B7 is the major isoform catalyzing the glucuronidation of a variety of endogenous compounds including bile acids. To determine the role of bile acids in the regulation of UGT2B7 expression, Caco-2 cells were incubated with the natural human farnesoid X receptor (hFXR) ligand, chenodeoxycholic acid, as well as the secondary bile acid, lithocholic acid, derived from chenodeoxycholic acid. Incubation of Caco-2 cells with lithocholic acid in the absence of exogenous hFXR resulted in a dose-dependent down-regulation of UGT2B7 mRNA levels, with an IC(50) of 13 microM. Similar down-regulation was also observed with chenodeoxycholic acid; however, much higher concentrations were required. Transient transfection of Caco-2 cells with hFXR suppressed UGT2B7 mRNA expression both in the absence and presence of ligand. UGT2B7 promoter transfection experiments and deletion/mutation analysis showed that lithocholic acid-activated hFXR decreased UGT2B7 promoter activity via a negative hFXR response element (NFRE) located between nucleotides -148 and -134. Cotransfection with hFXR and/or human retinoid X receptor further enhanced the repression. Electrophoretic mobility shift assays additionally confirmed the role of NFRE in UGT2B7 down-regulation by lithocholic acid. These findings suggest that lithocholic acid, an activator of nuclear hFXR, acts as a negative regulator of UGT2B7 expression, indicating that hFXR may play an essential role in lithocholic acid homeostasis through negative regulation of this UGT that is involved in lithocholic acid biotransformation. Therefore, it is postulated that lithocholic acid toxicity may be due to down-regulation of genes involved in its detoxification, including UGT2B7, leading to limited excretion of lithocholic acid from the body.     

Pharmacokinetics and safety of intravitreally delivered etanercept

Background The anti-inflammatory drug etanercept may be an effective therapeutic agent in diabetic retinopathy. In order to further evaluate its potential, the pharmacokinetics and safety of this drug after intravitreal delivery were investigated.Methods After intravitreal administration of etanercept in rabbits, clinical examination, electroretinography (ERG), visually evoked potentials (VEP) and histology were evaluated. The pharmacokinetics and distribution of etanercept were analyzed using fluorescence-coupled protein at 0, 2, 4, and 8 weeks after injection in vitreous, retina, and choroid.Results No adverse effects and signs of toxicity were found. Etanercept showed peak concentrations after 4 weeks in the retina and choroid.Conclusions Intravitreally delivered etanercept is safe and results in high concentrations in the retina and choroid over a long period of time.