| 1. |
- Lybak, Stein, et al.
(author)
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Normal tissue reactions in mice after combined treatment with metoclopramide and ionizing radiation
- 1992
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In: Acta Oncologica. - : Informa UK Limited. - 1651-226X .- 0284-186X. ; 31:4, s. 469-474
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Journal article (peer-reviewed)abstract
- We have previously shown that metoclopramide potentiates the effect of ionizing radiation and cisplatin treatment of human squamous cell carcinomas from the head and neck region xenografted to nude mice. In the present tumor study, the dose scheduling of metoclopramide in combination with radiation was evaluated, and metoclopramide was shown to be most effective in potentiating the cytotoxic effect of radiation when administered one hour before radiation. The effect of radiation in combination with metoclopramide on normal tissue was also studied in two well-established models. Acute skin reactions to radiation exposure were studied in 129-type mice, and metoclopramide did not enhance the acute skin reaction in this in vivo model. Survival after whole body irradiation was studied in heterozygote Balb/c nu/+ mice as a measure of bone marrow toxicity. Metoclopramide was not found to affect the LD50/30 in this in vivo model. The absence of potentiation of radiation damage to normal tissue in these animal studies, makes metoclopramide an interesting possibility for future clinical evaluation.
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| 2. |
- Tennvall, Jan, et al.
(author)
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DNA analysis as a predictor of the outcome of induction chemotherapy in advanced head and neck carcinomas
- 1993
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In: Archives of Otolaryngology - Head and Neck Surgery. - 1538-361X. ; 119:8, s. 867-870
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Journal article (peer-reviewed)abstract
- We investigated whether flow cytometric DNA index and/or ploidy status are predictors of response to chemotherapy and survival. Fifty consecutive patients with previously untreated locally advanced squamous cell carcinomas of the head and neck received induction chemotherapy consisting of three courses of cisplatin (100 mg/m2) and a subsequent 120-hour infusion of fluorouracil (1000 mg/m2 per 24 hours) repeated every 3 weeks. Chemotherapy was followed by radiotherapy to a median target dose of 65 Gy and subsequent surgery for residual tumor. The median observation time was 27 months (range, 24 to 57 months). Flow cytometric DNA analysis was based on formalin-fixed and paraffin-embedded tissue from pretreatment tumor biopsy specimens. Complete response after induction chemotherapy was achieved in only 12% (2/17) of patients with diploid tumors compared with 39% (13/33) of those with nondiploid tumors. Among patients with nondiploid tumors, DNA index was higher for those responding to chemotherapy compared with the nonresponders. Complete response to chemotherapy was apparently a prerequisite for survival in the nondiploid group. Of the patients not responding to chemotherapy but responding to subsequent radiotherapy, survival was better among those with diploid tumors than among those with nondiploid tumors.
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| 3. |
- Tennvall, Jan, et al.
(author)
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T3N0 glottic carcinoma: DNA S-phase as a predictor of the outcome after radiotherapy
- 1993
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In: Acta Oto-Laryngologica. - : Informa UK Limited. - 1651-2251 .- 0001-6489. ; 113:1, s. 220-224
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Journal article (peer-reviewed)abstract
- In consecutive series of 326 laryngeal cancer patients, of 29 (9%) with stage T3N0 glottic carcinomas, 23 achieved complete local remission after curative radiotherapy and form the basis of the present investigation. Flow cytometry determinations of DNA-ploidy status and the S-phase fraction, and a "histopathological malignancy grading system" were evaluated as possible patient- and/or tumor-related predictors of local recurrence. Twelve patients (52%) were continuously disease-free after radiotherapy, whereas 10 (43%) manifested local recurrence, and one distant metastasis. The radiotherapy delivered to patients who later suffered from a local recurrence did not differ from those being continuously disease-free. The frequency of local recurrence was significantly correlated to patients whose primary tumours manifested a low S-phase fraction (p < 0.05). A low S-phase fraction may indicate slowly proliferating tumour-cells, which become more radioresistant on exposure to a series of fractionated doses, as their reassortment into sensitive phases will be proportionately slower.
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| 4. |
- Zätterström, Ulf K, et al.
(author)
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Comparison of BrdUrd and [3H]TdR incorporation to estimate cell proliferation, cell loss, and potential doubling time in tumor xenografts
- 1992
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In: Cytometry. - : Wiley. - 0196-4763 .- 1097-0320. ; 13:8, s. 872-879
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Journal article (peer-reviewed)abstract
- In this study, two different methods of estimating cell proliferation were compared: cell loss and potential growth rate of xenografted head and neck cancer grown in nude mice based on the detection of DNA incorporation of bromodeoxyuridine (BrdUrd) in one method, and [3H]thymidine ([3H]TdR) in the other. The 21-d-old xenografts were labelled in vivo, either with BrdUrd or [3H]TdR and excised at intervals during 65.5 h. In tumors containing BrdUrd, the percent labelling was measured in mid-S and mid-G1 phase windows of cytograms from bivariate DNA flow cytometry (FCM). In [3H]TdR-labelled tumors, the percent labelled mitoses (PLM) was determined by light microscopy evaluation of autoradiographs. With a computer program based on a theoretical model, the percent labelling versus time after injection was used to analyze cell cycle time, cell loss, tumor growth fraction, and potential doubling time. The values calculated from DNA incorporation with BrdUrd agreed well with those obtained from labelling with [3H]TdR, i.e., cell cycle time 2.3 vs. 2.4 d, and growth fraction 67 vs. 70%. The estimated potential doubling time was 3.1 d and cell loss factor 40% by both methods. Flow cytometry analysis of BrdUrd-labelling is considerably faster than the evaluation of [3H]TdR-labelling, and the present results provide further support for the BrdUrd labelling method as a promising alternative to the PLM method in cell cycle studies designed to evaluate the relevance of cell proliferative properties in relation to biological behavior in xenografted head and neck cancer.
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