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1.
J Biochem Mol Toxicol ; 36(1): e22938, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34719826

RESUMO

Multidrug resistance (MDR) is the leading cause of treatment failure in triple-negative breast cancer (TNBC) patients treated with doxorubicin (DXR). We aimed to investigate the potential of the antidiarrheal drug Loperamide (LPR) in sensitizing TNBC cells to DXR and elucidate the underlying molecular mechanisms. Therefore, we examined the effects of DXR alone or in combination with LPR on MDA-MD-231 cells viability using MTT assay, cell cycle, and apoptosis by flow cytometry, and the expression of the MDR-related genes (MDR1 and JNK1) and cell cycle/survival genes (p21, mTOR, and Bcl-2) by quantitative reverse transcription polymerase chain reaction. Results showed that adding LPR to DXR potentiated its antiproliferation effect and reduced its IC50 by twofolds compared with DXR alone. The value of the combination index of LPR/DXR was <1 indicating a synergistic effect. Combined DXR/LPR treatment also caused G1 arrest and potentiated apoptosis more than DXR-single treatment. At the molecular levels, LPR/DXR treatment downregulated the mRNA of MDR1 (1.35-folds), JNK1 (2.5-folds), mTOR (6.6-folds), Bcl-2 (9.5-folds); while upregulated p21 gene (8-folds) compared with DXR alone. Molecular docking analyses found LPR antagonizes MDR1 and JNK1 proteins, and hence supports the in vitro studies. In conclusion, the results confirmed the potential of LPR in sensitizing TNBCs to DXR by targeting MDR1 and JNK1 and suppressing Bcl-2 and mTOR genes, while upregulating the cell cycle inhibitor gene p21. Additionally, LPR could be repurposed to reduce the therapeutic doses of DXR as indicated by the dose reduction index (DRI) and subsequently decrease its side effects.


Assuntos
Doxorrubicina/farmacologia , Loperamida/farmacologia , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/agonistas , Sinergismo Farmacológico , Feminino , Humanos , Loperamida/agonistas , Neoplasias de Mama Triplo Negativas/metabolismo
2.
J Neurooncol ; 132(3): 419-426, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28374095

RESUMO

The optimal management of recurrent glioblastoma (GBM) has yet to be determined. We aim to assess the benefits of re-operation and salvage therapies (chemotherapy and/or re-irradiation) for recurrent GBM and to identify prognostic factors associated with better survival. All patients who underwent surgery for GBM between January 2005 and December 2012 followed by adjuvant radiotherapy, and who developed GBM recurrence on imaging were included in this retrospective study. Univariate and multivariate analysis was performed using Cox models in order to identify factors associated with overall survival (OS). One hundred and eighty patients treated to a dose of 60 Gy were diagnosed with recurrent GBM. At a median follow-up time of 6.2 months, the median survival (MS) from time of recurrence was 6.6 months. Sixty-nine patients underwent repeat surgery for recurrence based on imaging. To establish the benefits of repeat surgery and salvage therapies, 68 patients who underwent repeat surgery were matched to patients who did not based on extent of initial resection and presence of subventricular zone involvement at recurrence. MS for patients who underwent re-operation was 9.6 months, compared to 5.3 months for patients who did not have repeat surgery (p < 0.0001). Multivariate analysis in the matched pairs confirmed that repeat surgery with the addition of other salvage treatment can significantly affect patient outcome (HR 0.53). Re-operation with additional salvage therapies for recurrent GBM provides survival prolongation at the time of progression.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Recidiva Local de Neoplasia/terapia , Terapia de Salvação/métodos , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Quimioterapia Adjuvante , Terapia Combinada , Progressão da Doença , Feminino , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Modelos de Riscos Proporcionais , Reirradiação , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
3.
ACS Pharmacol Transl Sci ; 3(6): 1330-1338, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33344906

RESUMO

Triple-negative breast cancers (TNBCs) comprise 10-15% of all breast cancers but with more resistance affinity against chemotherapeutics. Although doxorubicin (DOX) is the recommended first choice, it has observed cardiotoxicity together with apparent drug resistance. The anti-hyperglycemic drug, empagliflozin (EMP), was recently indicated to have in vitro anticancer potential together with its previously reported cardioprotective properties related to calmodulin inhibition. In this study, we carried out molecular docking studies which revealed the potential blocking of the calmodulin receptor by EMP through its binding with similar crucial amino acids compared to its cocrystallized inhibitor (AAA) as a proposed mechanism of action. Moreover, combination of DOX with EMP showed a slightly lower cytotoxic activity against the MDA-MB-231 cell line (IC50 = 1.700 ± 0.121) compared to DOX alone (IC50 = 1.230 ± 0.131), but it achieved a more characteristic arrest in the growth of cells by 4.67-fold more than DOX alone (with only 3.27-fold) in comparison to the control as determined by cell cycle analysis, and at the same time reached an increase in the total apoptosis percentage from 27.05- to 29.22-fold, compared to DOX alone as indicated by Annexin V-FITC apoptosis assay. Briefly, the aforementioned in vitro studies in addition to PCR of pro- and antiapoptotic genes (mTOR, p21, JNK, Bcl2, and MDR1) suggest the chemosensitization effect of EMP combination with DOX which can reduce the required therapeutic dose of DOX in TNBC and eventually will decrease its toxic side effects (especially cardiotoxicity), along with decreasing the chemoresistance of TNBC cells to DOX treatment.

4.
Curr Oncol ; 15(6): 286-92, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19079630

RESUMO

BACKGROUND: The use of fractionated stereotactic radiotherapy (FSRT) has evolved with technical advances in noninvasive immobilization, radiation delivery, and image guidance. The application of FSRT to pituitary tumours is aimed at reducing toxicity through improved dose conformality and reduced treatment margins. The aim of the present paper is to report our own experience and to review the published data on FSRT for pituitary macroadenomas. METHODS: Between September 2000 and October 2005, 13 patients with pituitary macroadenoma underwent FSRT at our institution. In 12 patients, radiotherapy treatment followed surgical resection (transsphenoidal resection in 8, frontal craniotomy in 3, and multiple transsphenoidal resections followed by craniotomy in 1). In 4 patients, the tumours were functional (2 adrenocorticotropic hormone-secreting, 1 prolactinoma, and 1 growth hormone-secreting); the tumours in the remaining patients were clinically non-secretory. Before radiation, 3 patients had panhypopituitarism, and 6 patients had visual field defects. All patients were treated with FSRT using non-coplanar micro-multileaf collimation portals. A median dose of 50.4 Gy (range: 45-60 Gy) was prescribed to the 76.9%-95.2% isodose surface and delivered in 1.8-Gy fractions. The median planning target volume (gross tumour plus 3 mm) was 33.5 cm3 (range: 3.2-75 cm3). RESULTS: After a median follow-up of 24 months (range: 6-60 months), local control was 100%. One patient achieved clinical complete response. Treatment was well tolerated acutely for all patients. Neither radiation-induced optic neuropathy nor any radiation-related endocrine dysfunction was observed in our patients. CONCLUSIONS: In accordance with published series, we found FSRT to be safe and effective in the management of large pituitary macroadenomas.

5.
J Natl Cancer Inst ; 79(4): 653-61, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2443737

RESUMO

An Mr-40,000 polypeptide (p40) was purified from a lung cancer cell line on the basis of its antigenicity with leukocytes from lung cancer patients in an in vitro immunological assay of leukocyte adherence inhibition. Here, the cells and mechanism responsible for recognizing the purified p40 organ-specific cancer neoantigen (OSN) were studied. Buffy coat leukocytes from lung cancer patients showed a bell-shaped dose response with a peak response at 0.75 micrograms/assay. Mononuclear cells showed a similar response pattern, whereas pure T-cells were unreactive. Monoclonal antibodies (MAbs) to T-cell differentiation antigens T3 and T4 inhibited the response in a dose-dependent fashion, whereas anti-T8 had no effect, indicating T helper cells and their T3-antigen receptor complex recognized the antigen. MAbs to class II major histocompatibility complex (MHC) antigens also inhibited the response, whereas MAbs to class I MHC had no effect, indicating an important role for class II MHC antigens of monocytes. None of the MAbs inhibited the response to OSN on membrane fragments, which is mediated by antibody-dependent monocytes. Trypsin- or cyanogen bromide-cleaved p40 OSN triggered a response at the same concentrations as the intact molecule. The p40 OSN incubated with live leukocytes showed less than 30% proteolytic digestion. The results indicate that class II-restricted T-cells recognize, via their antigen-specific cell surface receptors, contiguous sequences within the immunogenic tumor molecule in the context of the molecule or peptides binding to class II transplantation antigens.


Assuntos
Antígenos de Neoplasias/análise , Epitopos/análise , Antígenos de Histocompatibilidade Classe II/imunologia , Leucócitos/imunologia , Neoplasias Pulmonares/análise , Linfócitos T/imunologia , Anticorpos Monoclonais , Antígenos HLA/imunologia , Humanos , Teste de Inibição de Aderência Leucocítica , Peso Molecular
6.
Cancer Res ; 44(7): 2762-8, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6609766

RESUMO

In the leukocyte adherence inhibition (LAI) assay, about 34% of adherent T-cells from patients with breast cancer exhibit nonadherence to glass when incubated with extracts of autologous cancer but not with HLA-A, -B, and -C mismatched extracts of breast cancer. To determine whether the recognition by T-cells of tumor antigen was major histocompatibility complex restricted, major histocompatibility complex antigens in the cancer extracts or on the T-cells were coated with monoclonal antibody (MAb) to nonpolymorphic determinants. Nonadherence of T-cells was antagonized by coating the target cancer extracts with MAb to a common framework determinant of Class I HLA-A, -B, and -C antigens or to the nonpolymorphic beta 2-microglobulin, which is noncovalently associated with Class I antigens. By contrast, a MAb to a monomorphic determinant on HLA-DR antigens did not change the positive T-cell response. Moreover, coating the T-cells with MAb to HLA-A, -B, and -C did not inhibit the positive T-cell response. The positive LAI response of buffy coat peripheral blood leukocytes from patients with breast cancer to extracts of allogeneic breast cancer was not affected by coating the cancer extracts with the same MAb, indicating that MAb inhibited T-cell LAI specifically and that the antibody-dependent LAI response of buffy coat peripheral blood leukocytes was not major histocompatibility complex restricted. The results indicate that HLA-A, -B, and -C antigens in extracts of autologous breast cancer restrict the LAI response to tumor antigens of T-cells from patients with breast cancer.


Assuntos
Anticorpos Monoclonais , Neoplasias da Mama/imunologia , Complexo Principal de Histocompatibilidade , Linfócitos T/imunologia , Antígenos de Neoplasias/imunologia , Adesão Celular , Feminino , Vidro , Antígenos HLA/imunologia , Humanos , Teste de Inibição de Aderência Leucocítica , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário
7.
Cancer Res ; 44(3): 1238-45, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6420056

RESUMO

Assays of leukocyte adherence inhibition (LAI) and transmembrane potential (delta psi) change were used to examine the responses of T-cells from control subjects and breast cancer patients when incubated with extracts of breast cancer and other tissues. Of T-cells from 25 patients with breast cancer, 21 exhibited delta psi changes or inhibition of adherence to glass when they were incubated with extracts of autologous but not allogeneic breast cancer; extracts of autologous normal breast tissue did not induce delta psi changes or LAI in T-cells from patients with breast cancer. Supernatants were collected after incubating 1 X 10(7) T-cells from patients with breast cancer or from control subjects with extracts of the autologous cancer. When the supernatants were added to either peripheral blood leukocytes or mononuclear cells from normal donors, neither delta psi changes nor LAI were detected. To still determine whether the nonadherence was mediated by chemoattractant lymphokines, the effect of inhibiting T-cell arachidonic acid metabolism was examined. The lipoxygenase pathway antagonist, 5,8,11,14-eicosatetraynoic acid, or a leukotriene antagonist, FPL 55712, inhibited T-cell LAI, but a cyclooxygenase pathway antagonist, indomethacin, did not. Moreover, authentic leukotriene B4 induced delta psi changes and LAI in T-cells. The results indicated that T-cells from patients with breast cancer recognized and bound a tumor-specific antigen in the autologous neoplastic breast tissue that transduced a transmembrane signal to trigger a series of biochemical changes, releasing lipoxygenase products of arachidonate. The lipoxygenase products, which may be important in the inflammatory response to cancer, induced a loss of T-cell adherence to glass.


Assuntos
Ácidos Araquidônicos/metabolismo , Neoplasias da Mama/fisiopatologia , Leucócitos/imunologia , Neoplasias Hepáticas/secundário , Linfócitos T/imunologia , Ácido Araquidônico , Neoplasias da Mama/imunologia , Adesão Celular , Feminino , Humanos , Cinética , Teste de Inibição de Aderência Leucocítica , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/fisiopatologia , Potenciais da Membrana , SRS-A/farmacologia
8.
Curr Oncol ; 13(3): 108-15, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17576450

RESUMO

We assessed the effect of geometric uncertainties on target coverage and on dose to the organs at risk (OARS) during intensity-modulated radiotherapy (IMRT) for head-and-neck cancer, and we estimated the required margins for the planning target volume (PTV) and the planning organ-at-risk volume (PRV). For eight head-and-neck cancer patients, we generated IMRT plans with localization uncertainty margins of 0 mm, 2.5 mm, and 5.0 mm. The beam intensities were then applied on repeat computed tomography (CT) scans obtained weekly during treatment, and dose distributions were recalculated.The dose-volume histogram analysis for the repeat ct scans showed that target coverage was adequate (V(100) >/= 95%) for only 12.5% of the gross tumour volumes, 54.3% of the upper-neck clinical target volumes (CTVS), and 27.4% of the lower-neck CTVS when no margins were added for PTV. The use of 2.5-mm and 5.0-mm margins significantly improved target coverage, but the mean dose to the contralateral parotid increased from 25.9 Gy to 29.2 Gy. Maximum dose to the spinal cord was above limit in 57.7%, 34.6%, and 15.4% of cases when 0-mm, 2.5-mm, and 5.0-mm margins (respectively) were used for prv.Significant deviations from the prescribed dose can occur during IMRT treatment delivery for head-and-neck cancer. The use of 2.5-mm to 5.0-mm margins for PTV and PRV greatly reduces the risk of underdosing targets and of overdosing the spinal cord.

9.
Cancer Res ; 46(4 Pt 1): 1874-81, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2418955

RESUMO

Human cancers express organ-specific neoantigens (OSNs) that elicit immune responses in the tumor host. Leukocyte adherence inhibition, an in vitro assay that detects the antitumor immunity, was used to monitor the purification of the OSN from serum-free spent medium of tissue-cultured colon cancer cell lines (HCT-15 and SW-620). A monoclonal antibody (anti-p40) directed to a cross-reactive framework determinant of Mr 40,000 (p40) cell surface polypeptide, which was a principal component of the enriched isolate with OSN activity, was used to monitor the purification of p40 by enzyme-linked immunosorbant assay. About 50 liters of spent medium were generated from 20 m2 of cells, collected, concentrated, and then separated by anion exchange, molecular-sieve, and blue-Sepharose affinity chromatography. OSN and p40 activity coisolated. p40 was then purified by monoclonal antibody anti-p40 affinity chromatography. The affinity-purified fraction was enriched for both p40 and leukocyte adherence inhibition activity that was specific for leukocytes from colon cancer patients in blind leukocyte adherence inhibition assays. When affinity-purified p40 from colon and lung cancers was tested blind in a criss-cross fashion with leukocytes from colon and lung cancer patients, the positive responses were to the appropriate p40. The homologous colon cancer p40 molecule showed size and considerable charge microheterogeneity (pI 6.3 to 7.6). Affinity-purified p40 and OSN coisolated on hydrophobic interaction and hydroxylapatite high-pressure liquid chromatography. Note that not all colon cancer OSN activity was bound by the anti-p40 affinity column. However, unbound OSN activity also eluted from hydrophobic interaction high-pressure liquid chromatography at the same time as affinity-purified p40, and residual p40 activity was detected by enzyme-linked immunosorbant assay. The results indicate that a p40 glycoprotein from the cell membrane of colon cancer cells coisolates with fractions having OSN activity. Impurities do not seem to account for the OSN activity. The OSN epitope on the Mr 40,000 molecule is recognized by leukocytes from colon cancer patients and is distinct from the cross-reactive framework determinant recognized by mouse monoclonal antibody anti-p40.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Neoplasias do Colo/imunologia , Proteínas de Neoplasias/isolamento & purificação , Neoplasias Retais/imunologia , Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/imunologia , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Epitopos/análise , Humanos , Teste de Inibição de Aderência Leucocítica , Peso Molecular , Proteínas de Neoplasias/imunologia , Especificidade de Órgãos , Peptídeos/imunologia , Peptídeos/isolamento & purificação
10.
Cancer Res ; 47(4): 1058-64, 1987 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3100029

RESUMO

Immunoprotective tumor antigens of experimental tumors are selectively extracted by 1-butanol. Human organ-specific cancer neoantigens (OSNs) are tumor substances in cancer extracts to which patients with cancer of the same organ respond in the in vitro assay of leukocyte adherence inhibition. Here we determined whether OSNs as measured by leukocyte adherence inhibition assay are also selectively solubilized by 2.5% (v/v) 1-butanol. Butanol extracts of live tissue-cultured human cancer cells as well as extracts of primary breast cancer contained OSNs as determined by leukocyte reactivity in leukocyte adherence inhibition. With two-phase butanol, OSN activity was recovered in the aqueous and not in the organic phase, indicating that OSN is not a lipoprotein. The butanol-soluble OSN, whether allogeneic or autologous, was recognized by the T4 subset of T-cells in association with Class II major histocompatibility complex antigens of monocytes. Autologous OSN was extracted from membrane preparations of autologous primary cancer. Butanol extracts contained the previously identified Mr 40,000 protein OSN. Butanol removed about 50% of the Mr 40,000 protein OSN from live cancer cell membranes. Probably because of residual OSN in the membrane fragments and the ability of OSN to reassociate with the membrane, the T8 subset of pure T-cells responded positively to autologous cancer extracts. Passage of the autologous extract through an anti-Class I major histocompatibility complex antigen affinity column but not through a control affinity column negated the activity of the extract with pure autologous T-cells. The results indicate that human OSNs share with immunoprotective tumor antigens of experimental tumors the unique physicochemical property of being selectively extracted by 2.5% butanol.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Butanóis , Membrana Celular/análise , Neoplasias/análise , 1-Butanol , Antígenos de Diferenciação de Linfócitos T , Antígenos de Superfície/imunologia , Neoplasias da Mama/análise , Neoplasias do Colo/análise , Antígenos de Histocompatibilidade , Humanos , Teste de Inibição de Aderência Leucocítica , Neoplasias Pulmonares/análise , Matemática , Neoplasias da Bexiga Urinária/análise
11.
Int J Radiat Oncol Biol Phys ; 37(3): 587-91, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9112457

RESUMO

PURPOSE: Different radiotherapy fractionation schedules were used over a 10-year period to treat patients with early squamous cell carcinoma of the vocal cords at McGill University. A retrospective analysis was performed to study the effect of fraction size on local control in this group of patients. METHODS AND MATERIALS: A total of 126 previously untreated patients with T1 invasive squamous cell carcinoma of the true vocal cords were irradiated between January 1978 and December 1988 in the Department of Radiation Oncology at McGill University. All patients received megavoltage irradiation, 94 patients received daily fractions > 2 Gy (64 patients received 50 Gy with once-daily 2.5-Gy fractions, and 30 received 65.25 Gy in 29 fractions of 2.25 Gy each), and 32 patients were treated to a dose of 66 Gy in 33 fractions with 2 Gy/fraction. Patients' characteristics of prognostic importance were equally distributed between the two fractionation groups. RESULTS: At a median follow-up of 84 months, the 10-year disease-free survival and overall survival were 76% and 93%, respectively. Local control for patients treated with > 2 Gy fraction was 84%, compared to 65.6% for those treated with 2-Gy fractions (p = 0.026). Among the prognostic factors tested, such as gender, age, stage, anterior and posterior commissure involvement, smoking history, and fraction size, the latter was the only significant predictor of local control for the whole group of patients in univariate (p = 0.041) and multivariate (p = 0.023) analysis. There was no observed difference in the incidence of complications between the two fractionation groups. CONCLUSIONS: From the results of this retrospective review of patients treated with radiotherapy for T1 true vocal cord cancer, and within the range of total doses and overall treatment times used in our patients, it was found that fractionation schedules using daily fraction size > 2 Gy are associated with a better local control than schedules delivering 2 Gy/fraction, with no increase in toxicity.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Laríngeas/radioterapia , Prega Vocal , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Estudos Retrospectivos , Fatores Sexuais , Falha de Tratamento , Prega Vocal/patologia
12.
Int J Radiat Oncol Biol Phys ; 41(1): 37-42, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9588915

RESUMO

PURPOSE: Nonfunctional or mutated p53 protein (m-p53) is found in a myriad of solid tumors in humans. m-p53 is believed to confer radioresistance through inhibition of radiation-induced apoptosis. This study was carried out to determine if the overexpression of p53 in squamous cell carcinomas (SCC) of the glottic larynx treated with radiation therapy alone carried a poorer prognosis than normal wild-type p53 (w-p53) and could, therefore, be used as a marker of radioresistance in glottic SCC. METHODS & MATERIALS: Eighty-six patients with early-stage glottic SCC (64 T1N0, 25 T2N0 by TMN stage) treated with contemporary radiotherapy techniques to doses of 50-70 Gy were analyzed. Aberrant p53 protein was detected by immunohistochemical (IHC) staining on archival tissue samples containing original tumor specimens. Analysis of prognostic factors and treatment outcome to expression of p53 was performed. All patients were carefully selected to have comparable sites of disease, histology, early-stage disease, and treatment delivered, thus increasing the power of this study by controlling for other independent factors affecting outcome. RESULTS: Sixty percent of patients demonstrated overexpression of p53 in tissue samples. Accumulation of p53 was not predictive of tumor grade, stage, or smoking status prior to diagnosis. p53 status was not predictive of treatment outcome parameters including local-regional failure rate and disease-free survival rate. Factors significantly affecting treatment outcome were stage and dose of radiotherapy in T2 patients (50 Gy vs. > 62 Gy). CONCLUSION: m-p53 protein detected by IHC staining was not predictive as a prognostic factor for clinical outcome following radiation therapy for early-stage glottic SCC. This is in general agreement with other recently published studies of laryngeal carcinoma patients treated with radiation or surgery. At the present time, p53 status should not be used as a marker for prognosis and clinical outcome in laryngeal SCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/radioterapia , Proteínas de Neoplasias/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Feminino , Glote , Humanos , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico
13.
Int J Radiat Oncol Biol Phys ; 27(5): 1207-14, 1993 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8262849

RESUMO

PURPOSE: Previous radiation treatment of patients with recurrent Hodgkin's lymphoma hampers attempts to give these patients further radiation treatment for their recurrence, because of the potential for serious radiation damage to critical normal structures within the treatment volume. The purpose of this paper is to present a technique we developed for treatment of recurrent Hodgkin's lymphoma in mediastinum and hilum. The technique is based on parallel-opposed electron beams with a spinal cord shield in the posterior electron beam. METHODS AND MATERIALS: The patient was treated with parallel-opposed 20 MeV electron beams and the spinal cord shield was shaped in such a way that the total dose from both the anterior and posterior electron beams did not exceed 33% of the prescribed tumor dose. Wax bolus was used to obtain the desired separation for the electron beams. RESULTS: In an electron beam, the dose under the spinal cord shield depends not only on the depth of the spinal cord but also on the width of the shield. For a given shield width, as the cord depth increases the relative dose under the shield first increases, reaches a maximum, and then decreases to approach the open field depth dose data at large depths. The depth at which the relative dose maximum occurs increases slowly with the shielded width. At a given depth, the relative dose decreases with an increasing shield width. CONCLUSION: Parallel-opposed electron beams with a spinal cord shield in the posterior electron beam provide a viable option in treatment of tumors enveloping the spinal cord. A high tumor dose may be prescribed with a concurrent low dose to the spinal cord obtained with an appropriately shaped spinal cord shield.


Assuntos
Doença de Hodgkin/radioterapia , Neoplasias do Mediastino/radioterapia , Recidiva Local de Neoplasia/radioterapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Humanos , Mecloretamina/administração & dosagem , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/tratamento farmacológico , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Proteção Radiológica , Medula Espinal , Tomografia Computadorizada por Raios X , Vincristina/administração & dosagem
14.
Int J Radiat Oncol Biol Phys ; 40(2): 455-9, 1998 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9457835

RESUMO

PURPOSE: Results of treatment of patients with Stage I seminoma with orchiectomy and radiotherapy are excellent. Even without adjuvant radiotherapy, the relapse rate is only 15-20%; most of the patients fail in the retroperitoneum, with rare failures observed in the pelvis (0.5-2%). In 1991, we began a prospective study evaluating para-aortic lymph node radiation as the only adjuvant treatment for such patients. This paper reports our preliminary results. MATERIALS & METHODS: Between March 1991 and January 1996, 35 patients with histologically proven Stage I seminoma were entered in the study. Median age was 37.9 years (range: 27-65 years). A radical inguinal orchiectomy was performed in all patients. Staging workup consisted of a chest X-ray; B-HCG, alpha-fetoprotein, and CT scan of the abdomen and pelvis in all patients. Lymphangiogram was done in 23 (66%) of 35 patients for further evaluation of the retroperitoneal lymph nodes. Radiotherapy consisted of treatment to the para-aortic region only. Parallel opposed fields extending from the top of T11 to the bottom of L5 were used. The median field size was 8.7 x 21.8 cm (range: 7-11 x 18-26 cm). The median total dose, prescribed at midpoint, was 25 Gy given in 15 daily fractions of 1.66 Gy. Follow-up was performed every 3 months for the first year, every 4-5 months for the second and third years, and every 6 months thereafter. Chest X-ray, tumor markers, and CT scan of the pelvis were performed routinely as part of the follow-up investigation. RESULTS: At a median follow-up of 39.7 months (range: 16-74 months), 34 (97.1%) of 35 patients are alive with no evidence of disease for an overall actuarial survival rate of 97.1% at 5 years and a cause-specific actuarial survival rate of 100%. Treatment morbidity was limited to Grade I-II acute side effects in 18 (51.4%) of 35 patients. No late side effects were seen. CONCLUSION: From our preliminary results, adjuvant radiation treatment limited to the para-aortic lymph node region, without ipsilateral pelvic irradiation, appears to be adequate treatment for Stage I seminoma. Such an approach in our patients resulted in minimal toxicity and excellent disease-free survival.


Assuntos
Seminoma/radioterapia , Neoplasias Testiculares/radioterapia , Adulto , Idoso , Aorta Abdominal , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia , Estudos Prospectivos , Radioterapia Adjuvante , Espaço Retroperitoneal , Seminoma/mortalidade , Seminoma/patologia , Seminoma/cirurgia , Taxa de Sobrevida , Neoplasias Testiculares/mortalidade , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgia
15.
Radiother Oncol ; 40(1): 63-7, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8844890

RESUMO

PURPOSE: This study reports the clinical outcome of fifteen patients with low rectal adenocarcinoma treated with the long source-skin distance (SSD) of endorectal irradiation technique. This method was designed at McGill University in 1986 as an alternative to the standard short SSD rectal irradiation that was developed by Papillon (Proc. R. Soc. Med. 66: 1179-1181, 1973). METHODS AND MATERIALS: Between April 1986 and May 1993, six females and nine males were treated with this technique. Fourteen patients were treated with curative intent and one woman for palliation. The median total dose was 85 Gy (range 60-135 Gy) in a median of 3 fractions (range 3-5) over a median treatment time of 5 weeks (range 2-9.5 weeks). RESULTS: With a mean follow-up of 39 months and a median of 24 months (range 3 months-8.7 years), actuarial overall survival and disease-free survival rates are 50.8% and 71.4%, respectively, at 8.7 years. No patients have died of recurrent disease, but one patient has distant metastatic disease. One patient treated with curative intent required an abdominoperineal resection for progressive disease. Treatments were tolerated well by all patients. Four patients required steroid enemas for localized proctitis for a short period of time. They all responded well and had complete resolution of symptoms. CONCLUSIONS: Our results are comparable with those in other reports in the literature. The complications are similar in type and frequency to other published series. The long SSD technique may be an acceptable alternative to the standard short SSD technique.


Assuntos
Adenocarcinoma/radioterapia , Neoplasias Retais/radioterapia , Adenocarcinoma/mortalidade , Idoso , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Masculino , Radioterapia/instrumentação , Radioterapia/métodos , Dosagem Radioterapêutica , Neoplasias Retais/mortalidade , Taxa de Sobrevida , Fatores de Tempo
16.
Radiother Oncol ; 24(3): 155-62, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1410569

RESUMO

Between October 1981 and December 1989, 44 patients with cutaneous T-cell lymphoma (CTCL) were treated with a single field rotational total skin electron irradiation (RTSEI) technique developed in the McGill University, Department of Radiation Oncology. Only 11 (25%) of the 44 patients had received no prior treatment. Three-quarters (33/44) had advanced (T3 or T4) disease. Complete responses were seen in 32/44 (73%) of patients (91% T2, 71% T3 and 58% T4), but only 3/11 (27%) of patients with T2 disease and 3/21 (14%) of patients with T3 disease remain in continuous complete remission in the skin, after median intervals of 58 and 35 months, respectively. Median cause-specific survival for the whole group is 43 months and survival at 5 years is 38%. Survival was significantly better for patients with T2 disease than for patients with T3 disease (relative risk 4.3; 95% CI 1.4-13.2) and patients with T4 disease (relative risk 3.1; 95% CI 0.8-12.1). The RTSEI technique used at McGill has depth-dose characteristics and photon contamination similar to other commonly used TSEI techniques. It is relatively simple and provides a homogenous dose distribution over the entire skin surface in a short treatment time. Results of treatment are similar to those obtained with other techniques. For T2 disease, TSEI is an effective treatment modality with a possibility of long-term tumor control. For more advanced disease, more aggressive treatment, which may include TSEI, is necessary.


Assuntos
Linfoma Cutâneo de Células T/radioterapia , Radioterapia de Alta Energia/métodos , Neoplasias Cutâneas/radioterapia , Irradiação Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Linfoma Cutâneo de Células T/mortalidade , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Rotação , Neoplasias Cutâneas/mortalidade , Taxa de Sobrevida
17.
Int J Oncol ; 2(1): 115-8, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21573525

RESUMO

Tumour necrosis factor (TNF) has been implicated in the pathogenesis of cachexia in neoplastic and infectious diseases. In our study, the relationship between TNF and other cytokines in patients with malignancy was studied by measuring the serum levels of TNF, Interleukin-I (IL-1), Interleukin-2 (IL-2), and Interleukin-6 (IL-6). Eight patients with cancer had weight loss >10% of their body weight prior to starting anticancer therapy, and their weight loss was not attributable to gastrointestinal disorder, or other medical conditions. Seven patients with malignancy and no weight loss, as well as three normal donors without malignancy were also tested as controls. TNF, IL-1, IL-2 and IL-6 serum levels were determined using a quantitative ELISA test. Elevated levels of TNF, IL-1, IL-2 and IL-6 were detected in 25%, 12.5%, 12.5% and 50% of patients, respectively. In contrast, TNF levels were elevated in 28.5% of seven patients with cancer and no weight loss. In these patients, IL-1, IL-2 and IL-6 levels were undetectable. No TNF, IL-1, IL-2 or IL-6 could be detected in the sera of normal controls. Elevated cytokines serum levels, and especially IL-6, are detected in patients with cancer-cachexia. The determination of such cytokines may have a prognostic value.

18.
Cancer Chemother Pharmacol ; 26(6): 457-60, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2121379

RESUMO

In an attempt to examine the possibility of decreased toxicity in patients with advanced breast cancer who had not previously received chemotherapy, 33 women were given combination chemotherapy consisting of mitomycin C (10 mg/m2) every 6 weeks and mitoxantrone (6 mg/m2) every 3 weeks. The patients had predominantly visceral disease and received a median of two cycles of therapy. Of the 32 evaluable subjects, 15 (47%) achieved a partial response lasting a median of 7 months. Hematological toxicity was generally mild, although there were two episodes of sepsis. One patient developed hemolytic-uremic syndrome, and one subject developed pulmonary fibrosis, both presumably attributable to treatment with mitomycin C. Another patient died of hepatic failure (hepar lobatum). Thus, there were five patients who sustained life-threatening toxicities; this may have been due to the poor performance status and advanced age of some of the patients. Gastrointestinal toxicity and alopecia were minimal. Patient acceptance was high and there was an improvement in symptomatology in the majority of patients. In conclusion, mitomycin C and mitoxantrone chemotherapy is an active drug combination for the treatment of advanced breast cancer that seldom causes significant distressing gastrointestinal side effects or alopecia; however, the duration of response to this regimen appears to be shorter than that obtained with either cyclophosphamide - methotrexate - 5-fluorouracil (CMF) or cyclophosphamide - Adriamycin - 5-fluorouracil (CAF) combination chemotherapy.


Assuntos
Alopecia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Sistema Digestório/efeitos dos fármacos , Alquilantes/administração & dosagem , Alquilantes/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/sangue , Neoplasias da Mama/complicações , Feminino , Humanos , Mitomicina , Mitomicinas/administração & dosagem , Mitomicinas/efeitos adversos , Mitoxantrona/administração & dosagem , Mitoxantrona/efeitos adversos , Indução de Remissão , Fatores de Tempo
19.
Int J Impot Res ; 13(2): 104-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11426349

RESUMO

The objectives of this work were to: (1) Determine if prostate and penile tissue levels of endothelin-1 (ET-1) are increased in a rat following pelvic irradiation. (2) Determine if an ETa receptor antagonist (BQ-123) potentiates erectile function in these irradiated animals. Rats were divided into three study groups: control, 1000 cGy and 2000 cGy. The experimental groups received a single dose of radiation to the pelvic region. A time course was established to measure the effects of irradiation on prostate and penile tissue levels of endothelin-1 (ET-1)-like immunoreactivity. The effect of intracavernous injection of BQ-123 (25 microg/30 microl) was evaluated by measuring intracavernous pressure (ICP) following cavernous nerve electrical field stimulation. In the 2000 cGy group, a significant rise in ET-1-like immunoreactivity tissue levels was observed at 20 days. A significant decrease in ICP was recorded in the 1000 and 2000 cGy irradiated rats compared to the control group. Only the 2000 cGy group had a significant improvement in erectile function following BQ-123 administration. A significant improvement was observed 20 min post-administration, lasted 90 min, and was back to pre-administered levels at 120 min. The conclusion made was that radiation-induced impotence in irradiated rats is associated with an increased production of ET-1. Preliminary results are suggestive that ETa receptor antagonist may be of use to reverse such radiation-induced impotence in these irradiated animals.


Assuntos
Endotelina-1/fisiologia , Disfunção Erétil/etiologia , Disfunção Erétil/fisiopatologia , Lesões por Radiação/complicações , Animais , Estimulação Elétrica , Antagonistas dos Receptores de Endotelina , Injeções , Masculino , Pelve/diagnóstico por imagem , Ereção Peniana/efeitos dos fármacos , Pênis/patologia , Pênis/fisiopatologia , Peptídeos Cíclicos/farmacologia , Pressão , Próstata/patologia , Radiografia , Ratos , Ratos Sprague-Dawley , Receptor de Endotelina A , Fatores de Tempo
20.
Neurosurgery ; 46(2): 306-18, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10690719

RESUMO

OBJECTIVE: Most patients with a malignant glioma spend considerable time on a treatment protocol before their response (or nonresponse) to the therapy can be determined. Because survival time in the absence of effective therapy is short, the ability to predict the potential chemosensitivity of individual brain tumors noninvasively would represent a significant advance in chemotherapy planning. METHODS: Using proton magnetic resonance spectroscopic imaging (1H MRSI), we studied 16 patients with a recurrent malignant glioma before and during treatment with high-dose orally administered tamoxifen. We evaluated whether 1H MRSI data could predict eventual therapeutic response to tamoxifen at the pretreatment and early treatment stages. RESULTS: Seven patients responded to tamoxifen therapy (three with glioblastomas multiforme; four with anaplastic astrocytomas), and nine did not (six with glioblastomas multiforme; three with anaplastic astrocytomas). Responders and nonresponders exhibited no differences in their age, sex, tumor type, mean tumor volume, mean Karnofsky scale score, mean number of weeks postradiotherapy, or mean amount of prior radiation exposure. Resonance profiles across the five metabolites measured on 1H MRSI spectra (choline-containing compounds, creatine and phosphocreatine, N-acetyl groups, lactate, and lipids) differed significantly between these two groups before and during treatment. Furthermore, linear discriminant analyses based on patients' in vivo biochemical information accurately predicted individual response to tamoxifen both before and at very early treatment stages (2 and 4 wk). Similar analyses based on patient sex, age, Karnofsky scale score, tumor type, and tumor volume could not reliably predict the response to tamoxifen treatment at the same time periods. CONCLUSION: It is possible to accurately predict the response of a tumor to tamoxifen on the basis of noninvasively acquired in vivo biochemical information. 1H MRSI has potential as a prognostic tool in the pharmacological treatment of recurrent malignant gliomas.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Astrocitoma/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Recidiva Local de Neoplasia/tratamento farmacológico , Tamoxifeno/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Astrocitoma/diagnóstico , Astrocitoma/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Colina/metabolismo , Creatina/metabolismo , Relação Dose-Resposta a Droga , Feminino , Glioblastoma/diagnóstico , Glioblastoma/metabolismo , Humanos , Metabolismo dos Lipídeos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/metabolismo , Fosfocreatina/metabolismo , Resultado do Tratamento , Ensaio Tumoral de Célula-Tronco
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