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11.
The ectopic expression of Fc gamma RII by PyV transformed 3T3 cells derived from tumors of long latency has been established. It was suggested that this expression is one of several changes conferring upon the cells an increased capacity for survival. We found that in one case cells expressing a very high level of Fc gamma RII had also a very high metastatic phenotype as compared to FcR negative cells. Direct evidence that Fc gamma RIIbl functions as a progression factor was provided by transfection experiments. The transfected gene conferred an increased malignancy and invasive phenotype upon PyV or c-Ha-ras transformed cells. In the present study we tested the possibility that Fc gamma RII expressing tumor cells could interfere with the immune system. The following subjects were investigated: 1) The ability of Fc gamma R on the tumor cells to bind the ligand and/or release IBF. 2) The effect of a local accumulation of ligand and/or IBF (assumed to take place in situ in the tumor) on Fc gamma RII expressing T cells. It was found that both tumor-derived receptor positive and beta l transfected PyV transformed cells were capable of binding aggregated mouse IgG. The binding of bivalent ligand was followed by an increase in membrane Fc gamma RII expression. Also both types of cells were capable of releasing IBF. We then tested the possibility that a local accumulation of IgG within the tumor could effect Fc gamma R expressing T cells. It was found that aggregated mouse IgG (as well as IgGl) could stimulate the proliferation of the T cell hybridoma (T2D4) and other Fc gamma RII expressing T cells. We also found that the expression of beta Fc gamma RII specific mRNA peaked at the logarithmic phase of T2D4 cultures, in parallel with their maximal potential to release IBF. Several pathways for interference with the immune system are suggested.  相似文献   
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PURPOSE: The antitumor efficacy of a herpes simplex virus (HSV)-1 oncolytic virus depends on the cytotoxic effect of the virus, but also on viral replication and spread within the tumor. Apoptosis is considered a defense mechanism of infected cells that minimizes the spread of viral progeny by limiting cellular production of virus. We sought to determine whether oncolytic HSV-1 infection induces apoptosis in neighboring, uninfected cells and whether manipulation of apoptosis can increase viral replication and cytotoxicity. EXPERIMENTAL DESIGN: NV1066 is an oncolytic HSV-1 mutant that contains the marker gene for enhanced green fluorescent protein. OCUM human gastric cancer cells were infected with NV1066 in vitro and inspected for apoptosis by Hoechst and terminal deoxynucleotidyltransferase-mediated nick end labeling staining and for infection by expression of green fluorescence. RESULTS: A significant increase in apoptosis was seen in cells infected by NV1066. More interestingly, a significant percentage (10%) of uninfected cells also proceeded to apoptosis. After NV1066 infection, cells were also treated with N-acetylcysteine (NAC), an inhibitor of apoptosis. By day 4 after infection, 2.7x more NV1066 was produced in cells exposed to NAC than in those not exposed to NV1066 (P = 0.04). NAC also increased tumor kill when administered with virus. CONCLUSIONS: These data suggest that NV1066 induces apoptosis in uninfected cocultured cells, potentially hindering propagation of viral progeny and concomitant tumor kill. Inhibition of apoptosis may improve the efficacy of oncolytic HSV-1 therapy.  相似文献   
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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.  相似文献   
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PURPOSE: To determine the maximum-tolerated dose (MTD) of concurrent systemic oxaliplatin (Oxal) combinations plus hepatic arterial infusion (HAI) in patients with unresectable hepatic metastases from colorectal cancer. PATIENTS AND METHODS: Thirty-six patients (89% previously treated) with unresectable liver metastases were treated with concurrent HAI and systemic Oxal plus irinotecan (CPT-11; group A) or Oxal, fluorouracil (FU), and leucovorin (LV; group B). Systemic chemotherapy was administered every 2 weeks concurrent with 2 weeks of HAI floxuridine (FUDR) and dexamethasone (Dex) every 28 days. RESULTS: The MTD for patients in group A was Oxal 100 mg/m(2), CPT-11 150 mg/m(2), and FUDR 0.12 mg/kg x 30 mL divided by pump flow rate. The MTD for group B was Oxal 100 mg/m(2), LV 400 mg/m(2), and FU 1,400 mg/m(2) by continuous infusion over 48 hours, with the same FUDR dose as in group A. Grade 3 or 4 toxicities in groups A and B included diarrhea (24% and 20%), neutropenia (10% and 7%), neurotoxicity (24% and 20%), and bilirubin more than 3 mg/mL (5% and 7%, respectively). The complete and partial response rate totaled 90% for group A and 87% for group B. Median survival time was 36 and 22 months for groups A and B, respectively. Seven patients in group A were ultimately able to undergo liver resection. CONCLUSION: Combination therapy with HAI FUDR and Dex plus systemic Oxal combinations may be safely administered to patients with colorectal cancer. The high response rate (88%) and the possibility of conversion to resectability, despite disease progression on prior systemic regimens, suggest that these combinations should be evaluated in larger studies as first- or second-line therapy in patients with hepatic metastases from colorectal cancer.  相似文献   
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PURPOSE: Cancer-testis genes mapping to the X chromosome have common expression patterns and show similar responses to modulators of epigenetic mechanisms. We asked whether cancer-testis gene expression occurred coordinately, and whether it correlated with variables of disease and clinical outcome of non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Tumors from 523 NSCLC patients undergoing surgery were evaluated for the expression of nine cancer-testis genes (NY-ESO-1, LAGE-1, MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7/MAGE-C1, SSX2, and SSX4) by semiquantitative PCR. Clinical data available for 447 patients were used to correlate cancer-testis expression to variables of disease and clinical outcome. RESULTS: At least one cancer-testis gene was expressed by 90% of squamous carcinoma, 62% of bronchioloalveolar cancer, and 67% of adenocarcinoma samples. Statistically significant coexpression was observed for 34 of the 36 possible cancer-testis combinations. Cancer-testis gene expression, either cumulatively or individually, showed significant associations with male sex, smoking history, advanced tumor, nodal and pathologic stages, pleural invasion, and the absence of ground glass opacity. Cox regression analysis revealed the expression of NY-ESO-1 and MAGE-A3 as markers of poor prognosis, independent of confounding variables for adenocarcinoma of the lung. CONCLUSIONS: Cancer-testis genes are coordinately expressed in NSCLC, and their expression is associated with advanced disease and poor outcome.  相似文献   
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The aim of the present study was to perform clinical, biochemical, and radiological evaluation of the efficacy of mesenchymal stem cells derived from Wharton jelly (WJ) present within the human umbilical cord in the treatment of knee osteoarthritis. Between 2018 and 2019, 10 patients with knee osteoarthritis for whom the conservative treatment was not beneficial were included in the study. Patients were clinically, radiologically, and biochemically evaluated before treatment initiation. Thereafter, the patients were intra-articularly injected using a solution containing 1 × 108 WJ-derived MSCs. Evaluations were performed on day 21 (V1) and 42 (V2) and month 3 (V3), 6 (V4), and 12 (V5) after the procedure. At 1-year post-injection, visual analogue scale, Western Ontario and McMaster Universities Osteoarthritis Index, and Lequesne scores of patients were lower than those observed during the initial evaluation, whereas the mean 36-Item Short Form Health Survey score was higher. Cartilage thicknesses were found to be increased in all regions except in the medial femur, medial posterior femur, lateral posterior femur, and lateral posterior tibia regions in magnetic resonance imaging. A significant increase was observed in tumor necrosis factor-alpha, interleukin-1β, adiponectin, resistin, and interleukin-6 levels compared with pre-injection values. The leptin levels at 6-month and 1-year controls were lower than the pre-injection levels, and the decrease observed at 6 months was significant. In patients with knee osteoarthritis, intra-articular WJ-derived MSC injection causes significant pain reduction, satisfactory functional improvement, and increased patient satisfaction following a 1-year follow-up. These clinical improvements were supported by magnetic resonance images, along with changes in adiponectin and leptin levels in synovial fluid.Level of evidence: IV.  相似文献   
19.
BackgroundDrug manufacturers claim that the purpose of financial payments to physicians is to facilitate education about new drugs. This claim suggests 2 testable hypotheses: payments should not be associated with drug revenue and payments for each drug should decline over time as physicians become educated.Materials and MethodsWe used open payments data on industry payments. We included payments for cancer drugs without generic/biosimilar competitors and used federal data sources to measure Medicare spending (a proxy for overall drug revenue) and a number of prescribers. We used generalized estimating equations (GEE) to model the drug-level association between industry payments and Medicare spending. Separately, we used GEE to estimate the change in payments with respect to the duration of time since initial FDA approval.ResultsThe sample included 89 drugs and 361 drug-year observations. The total value of industry payments for oncology drugs increased, from $53 333 854 in 2014 to $90 343 731 in 2018. There was no association between log-transformed mean, per-physician industry payments, and per-physician Medicare spending (estimate −0.001, 95%CI, −0.005 to 0.004). Payments for individual drugs decreased over time; estimated payments in the subsequent year for a drug with mean, per-physician payments of $1000 in the index year was: $681* for drugs 0-4 years since approval, $825 for 5-9 years, and $679* for ≥10 years (*P < .05).ConclusionsAlthough industry-sponsored education may also serve marketing purposes, the absence of association between industry payments and Medicare spending and the decline in payments subsequent to approval are consistent with claims that industry payments function to facilitate physician education.  相似文献   
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Suffering comes in many ways for patients confronting cancer. One of these is an unspecifiable fear about death, which is an existential issue. The aim of this study was to investigate the relationship between death anxiety and its correlates in cancer patients. Seventy cancer patients were assessed using SCID-I, Templer's Death Anxiety Scale, the Hospital Anxiety (A) and Depression (D) Scale, the Distress Thermometer, the Visual Analogue Scale for pain (VAS), the Global Assessment of Functioning, and Glock and Stark's Dimensions of Religious Commitment scales, and these assessments were compared between cancer patients with and without death anxiety. Multiple regression analysis was conducted after correlation analysis between death anxiety and sociodemographic and clinical variables. Axis I psychiatric diagnosis, pain scores, and negative believes about what will happen after death were found to be higher in patients having death anxiety than patients not having death anxiety. Also life expectancy was perceived as shortened in patients with death anxiety. Death anxiety was associated with anxiety, depressive symptoms, and beliefs about what will happen after death. In conclusion, death anxiety could not be regarded as a natural consequence of having cancer; it is associated with the unresolved psychological and physical distress.  相似文献   
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