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101.
Esther G C Troost Johan Bussink Johannes H A M Kaanders Julli?tte van Eerd Johannes P W Peters Paulus F J W Rijken Otto C Boerman Albert J van der Kogel 《Radiotherapy and oncology》2005,76(2):194-199
PURPOSE: In head and neck cancer, it has been shown that hypoxic tumors respond poorly to therapy. Methods to identify hypoxic tumors are, therefore, of importance to select patients for oxygenation modifying or other intensified treatments. The aim of this study was to compare tumor cell hypoxia assessed by the hypoxic cell marker pimonidazole (PIMO) with expression of the endogenous hypoxia-related marker carbonic anhydrase IX (CAIX) in three human head and neck tumor lines. MATERIAL AND METHODS: Forty-five tumors of three human head and neck tumor lines, SCCNij3, SCCNij59 and MEC82, xenografted in athymic mice, were used. CAIX was quantified by biodistribution (% injected dose/g tumor) after injecting 3-5 microl 111In-labeled G250 mouse antibody 3 days prior to euthanizing. In a tissue section from the same tumor, fractions of tumor area positive for PIMO, CAIX and Hoechst 33342 (perfusion marker) were assessed after immunohistochemical staining, using a digital image analysis system. RESULTS: SCCNij3 and MEC82 were relatively hypoxic tumor lines with fractions of tumor area positive for pimonidazole of 0.16 and 0.15, respectively. SCCNij59 was a better-oxygenated tumor line with a PIMO-fraction of 0.03. The three tumor lines showed different levels and patterns of CAIX immunohistochemical staining, but only in MEC82 there was a good correlation between PIMO-fraction and CAIX-fraction (r2=0.92, P<0.0001). Correlations between 111In-G250 uptake and CAIX-fraction or PIMO-fraction within tumor lines were weak or absent. CONCLUSIONS: Assessment of CAIX expression depends largely on the techniques and tumor lines used. Furthermore, the immunohistochemical staining pattern of CAIX relative to PIMO differs between human tumor lines of similar anatomical origin. Therefore, the use of CAIX as endogenous marker of tumor hypoxia remains questionable. 相似文献
102.
Michiel S van der Heijden Jonathan R Brody David A Dezentje Eike Gallmeier Steven C Cunningham Michael J Swartz Angelo M DeMarzo G Johan A Offerhaus William H Isacoff Ralph H Hruban Scott E Kern 《Clinical cancer research》2005,11(20):7508-7515
PURPOSE: BRCA2, FANCC, and FANCG gene mutations are present in a subset of pancreatic cancer. Defects in these genes could lead to hypersensitivity to interstrand cross-linkers in vivo and a more optimal treatment of pancreatic cancer patients based on the genetic profile of the tumor. EXPERIMENTAL DESIGN: Two retrovirally complemented pancreatic cancer cell lines having defects in the Fanconi anemia pathway, PL11 (FANCC-mutated) and Hs766T (FANCG-mutated), as well as several parental pancreatic cancer cell lines with or without mutations in the Fanconi anemia/BRCA2 pathway, were assayed for in vitro and in vivo sensitivities to various chemotherapeutic agents. RESULTS: A distinct dichotomy of drug responses was observed. Fanconi anemia-defective cancer cells were hypersensitive to the cross-linking agents mitomycin C (MMC), cisplatin, chlorambucil, and melphalan but not to 5-fluorouracil, gemcitabine, doxorubicin, etoposide, vinblastine, or paclitaxel. Hypersensitivity to cross-linking agents was confirmed in vivo; FANCC-deficient xenografts of PL11 and BRCA2-deficient xenografts of CAPAN1 regressed on treatment with two different regimens of MMC whereas Fanconi anemia-proficient xenografts did not. The MMC response comprised cell cycle arrest, apoptosis, and necrosis. Xenografts of PL11 also regressed after a single dose of cyclophosphamide whereas xenografts of genetically complemented PL11(FANCC) did not. CONCLUSIONS: MMC or other cross-linking agents as a clinical therapy for pancreatic cancer patients with tumors harboring defects in the Fanconi anemia/BRCA2 pathway should be specifically investigated. 相似文献
103.
Rosalie M Luiten Esther W M Kueter Wolter Mooi Maarten P W Gallee Elaine M Rankin Winald R Gerritsen Shirley M Clift Willem J Nooijen Pauline Weder Willeke F van de Kasteele Johan Sein Paul C M van den Berk Omgo E Nieweg Anton M Berns Hergen Spits Gijsbert C de Gast 《Journal of clinical oncology》2005,23(35):8978-8991
PURPOSE: To determine the feasibility, toxicity, and immunologic effects of vaccination with autologous tumor cells retrovirally transduced with the GM-CSF gene, we performed a phase I/II vaccination study in stage IV metastatic melanoma patients. PATIENTS AND METHODS: Sixty-four patients were randomly assigned to receive three vaccinations of high-dose or low-dose tumor cells at 3-week intervals. Tumor cell vaccine preparation succeeded for 56 patients (88%), but because of progressive disease, the well-tolerated vaccination was completed in only 28 patients. We analyzed the priming of T cells against melanoma antigens, MART-1, tyrosinase, gp100, MAGE-A1, and MAGE-A3 using human leukocyte antigen/peptide tetramers and functional assays. RESULTS: The high-dose vaccination induced the infiltration of T cells into the tumor tissue. Three of 14 patients receiving the high-dose vaccine showed an increase in MART-1- or gp100-specific T cells in the peripheral blood during vaccination. Six patients experienced disease-free survival for more than 5 years, and two of these patients developed vitiligo at multiple sites after vaccination. MART-1- and gp100-specific T cells were found infiltrating in vitiligo skin. Upon vaccination, the T cells acquired an effector phenotype and produced interferon-gamma on specific antigenic stimulation. CONCLUSION: We conclude that vaccination with GM-CSF-transduced autologous tumor cells has limited toxicity and can enhance T-cell activation against melanocyte differentiation antigens, which can lead to vitiligo. Whether the induction of autoimmune vitiligo may prolong disease-free survival of metastatic melanoma patients who are surgically rendered as having no evidence of disease before vaccination is worthy of further investigation. 相似文献
104.
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107.
108.
Ylva Dahlin Redfors Sara Olaison Jan Karlsson Johan Hellgren Claes Möller 《International journal of audiology》2015,54(2):63-69
Objectives: The aims of the study were to assess health-related quality of life and hearing-related disability in subjects with otosclerosis 30 years after surgery. Design: An observational study was performed. Medical records were reviewed, a clinical examination as well as audiometric assessments were performed. Generic health-related quality of life was assessed by the SF-36v2 and hearing disability by a shortened version of SSQ (speech spatial and qualities of hearing scale). Study sample: Sixty-five individuals, who had undergone stapedectomy in 1977-79 at a tertiary referral center. Results: Generic health-related quality of life according to SF-36 subscale scores was comparable to that of an age- and sex-matched reference population. The SF-36 mental component summary score (MCS) was, however, significantly better than that of the reference population. The mental and physical summary component scores correlated significantly to hearing disability measured by the SSQ but not to hearing impairment. Hearing disability was displayed in all SSQ sub-scores, especially in more complex listening situations and in the localization of sounds. Conclusions: This study shows that individuals with otosclerosis, 30 years after surgery, have a good generic health-related quality of life, despite moderate to severe hearing loss and significant hearing disabilities. 相似文献
109.
110.
We retrospectively compared the first trimester Down's syndrome serum screening markers free beta-hCG (fbetahCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11-14 weeks of gestation in 4,088 women with naturally conceived pregnancies and in women pregnant after ICSI (n = 163), IVF (n = 59) and frozen-thawed embryo transfer (n = 31), and we searched for a potential relationship between infertility cause and marker levels. We found lower serum PAPP-A levels in pregnancies after IVF and ICSI compared with spontaneously conceived pregnancies and non-male factor infertility was associated with elevated serum fbetahCG levels at 11-14 weeks of gestation. 相似文献