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1.
One of the most promising substances used in photodynamic therapy (PDT) is 5-aminolevulinic acid (ALA), which induces endogenous synthesis and accumulation of porphyrins in malignant cells. In this paper we have shown that both topical and intratumoral administration of ALA in a subcutaneously implanted mammary carcinoma produced a significant synthesis of porphyrins and subsequent sensitization to laser light. Porphyrin accumulation was greater when ALA was administered intratumorally and tumour/normal skin porphyrin concentration ratios were higher compared with topical application. Irradiation was optimal between 2 and 3 h after topical application of 50 mg of a 20% ALA cream and 2-4 h after intratumoral administration of 30 mg ALA/cm3. The pattern of tumour response evaluated as the delay of tumour growth was similar following either route of drug administration. Applications of PDT were performed once, twice or three times in the study. The response to successive applications was constant for the same tumour, indicating that no resistance was acquired. Microscopic analysis showed both induction of foci of necrosis and haemorrhage, morphological features of apoptotic cells and total absence of cellular immune response. This paper reports on PDT with topical ALA in a subcutaneous carcinoma leading to tumour growth delay. These findings may have great relevance in the treatment of cutaneous metastasis of mammary carcinomas.  相似文献   

2.
An attenuated strain of Salmonella typhimurium was used as a vehicle for oral gene therapy against murine tumor. Eukaryotic expression vectors containing genes of human interleukin-12 (hIL-12), human granulocyte/macrophage colony-stimulating factor (hGM-CSF), mouse (m)IL-12, mGM-CSF and green fluorescent protein (GFP) were used to transform attenuated Salmonella (SL3261), and such transformants were administered orally to BALB/c and C57BL/6 mice. As a reporter gene, GFP expression in murine liver, spleen, tumor, intestine and kidney was confirmed by confocal and flow cytometry. Soluble cytokines were detected in murine sera, and the concentrations were much higher than those of the control, which contributed to the increased number of cytotoxic T cells and prolongation of survival. Oral cytokine gene therapy using live attenuated Salmonella demonstrated a significant protection against the development of two unrelated murine tumors. These results suggest that such gene therapy has the potential to be simple, effective and (above all) safe against tumor.  相似文献   

3.
A group of 99 patients with endometrial cancer clinically confined to the uterus has been treated with preoperative adjunctive intracavitary irradiation followed within 72 hours by total abdominal hysterectomy and bilateral salpingoophorectomy. Those patients with poorly differentiated tumors, deep myometrial invasion, cervical involvement, or pelvic metastasis were then considered for external beam radiotherapy to the whole pelvis because of the increased risk of involvement of pelvic nodes or other pelvic structures. Only one of 16 patients so treated has failed in the pelvis. The overall Berkson-Gage actuarial survival at 3 years, uncorrected for death from intercurrent disease, is 85.8%. No vaginal recurrences have been identified. Although this series has not been randomized, it appears that there has been a reduction in vaginal and pelvic recurrences when compared with patients reported by others who have received no adjuvant radiotherapy. The low recurrent rate and favorable survival in this group of patients was achieved with low morbidity from this treatment technique.  相似文献   

4.
We have previously reported that the use of the polymer bis(p-carboxyphenoxy)propane-sebacic acid (20:80) for intratumoral delivery of cis-platinum in a mouse tumor model (RIF-1) potentiated the effects of acute and fractionated radiation. This mode of drug delivery seems particularly applicable to the administration of radiosensitizing drugs because an optimum concentration of radiosensitizer can be maintained in the tumor over the prolonged period required for fractionated radiation treatment. We have now investigated, in the same tumor model, radiosensitization by the thymidine analogue bromodeoxyuridine (BrdUrd). BrdUrd (20%, w/w) was incorporated into bis(p-carboxyphenoxy)propane-sebacic acid (20:80) and polymer rods containing the drug implanted in the RIF-1 tumor. Preliminary in vitro studies of the rate of release of BrdUrd from the polymer showed an initial rapid loss over 24 h, followed by a slower release extending over the next 5 days. In experiments in which tumor cells, which had incorporated BrdUrd in vivo from implanted polymer, were excised and a single cell suspension irradiated in vitro radiosensitization indicative of BrdUrd incorporation was associated mainly with an increase in the alpha constant for the linear quadratic model of cell survival. Radiosensitization was seen for tumor cells harvested between 5 and 10 days after polymer implant, a finding that is consistent with results of experiments in which the percentage of cells that had incorporated BrdUrd were measured by flow cytometry at various times after polymer/BrdUrd implant. The proportion of tumor cells positive for BrdUrd was 40-50% between 3 and 8 days after polymer implant. When tumors were irradiated in situ and response measured in terms of tumor growth delay (TGD), radiosensitization was not seen for an acute dose of 16.5 Gy. In contrast, significant radiosensitization was seen for fractionated treatments when polymer/BrdUrd was implanted 3 days before the first radiation dose. For a dose of 5 x 6 Gy, TGD was increased from 22 days for radiation alone to 27 days for radiation plus polymer implant. For 10 x 6 Gy fractions, TGD increased from 45-77 days for those mice in whom the tumor eventually regrew, whereas for 25% of the mice in this group the tumor volume was reduced to a point where it was no longer detectable and there was no recurrence for at least 120 days after treatment.  相似文献   

5.
Photodynamic therapy consists of the systemic administration of a derivative of haematoporphyrin (Photofrin II) followed 24-72 h later by exposure of malignant lesions to photoradiation. We investigated the efficacy of this treatment after direct intratumoral injection of Photofrin II. This direct treatment regimen resulted in higher rates of inhibition of mitochondrial cytochrome c oxidase (5.13% J-1 cm-2 x 10(-1) and succinate dehydrogenase (3.14% J-1 cm-2 x 10(-1] in vitro at 2 h after intratumoral injection compared to rates of inhibition obtained after intraperitoneal drug administration: 0.51 and 0.42% J-1 cm-2 x 10(-1), respectively. A significant delay in tumour growth in vivo was observed in animals that received intratumoral injections 2 h before photoradiation compared to animals injected intraperitoneally at either 2 or 24 h before photoradiation. The treatment protocols were compared with control groups, consisting of Photofrin II administration intratumorally or intraperitoneally without photoradiation, or photoradiation in the absence of Photofrin II. These data indicate that the intratumoral injection regimen with Photofrin II enhanced the efficacy of photodynamic therapy. The greater delay in tumour growth observed after intratumoral administration of Photofrin II suggests a mechanism favouring direct cell damage.  相似文献   

6.
The aim of this study was to examine the enhancement of antitumor immunity of irradiated granulocyte macrophage-colony-stimulating factor (GM-CSF) gene-transduced mouse breast cancer cells. METHODS: BALBMC mouse were vaccinated subcutaneously with saline or irradiated mouse breast cancer cells, BALBMC (1 x 10(6)/mouse), infected or not infected with recombinant adenovirus harboring GM-CSF gene on day-7. Mice were injected with parental cells (1 x 10(5)/mouse) on day 0. RESULTS: No mice vaccinated with irradiated GM-CSF producing BALBMC cells developed a tumor during the observation period of up to 16 weeks, whereas 100% of mice injected with saline developed a tumor. CONCLUSION: Our study demonstrates the feasibility of this immunotherapeutic approach as a novel adjuvant cancer therapy after surgery for breast cancer.  相似文献   

7.
Immune responses to tumor-associated antigens are often dampened by a tumor-induced state of immune anergy. Previous work has attempted to overcome tumor-induced T-cell anergy by the direct injection of vectors carrying the genes encoding one of a variety of cytokines. We hypothesised that the polyclonal stimulation of T cells, preferably through the TCR complex, would result in a cascade of cytokines associated with T-cell activation and would be best able to overcome T-cell anergy. Here we use the highly attenuated MVA poxvirus to express on tumor cells, in vitro and in vivo, either of three membrane-bound monoclonal antibodies specific for murine TCR complex. Using this system, we have expressed antibodies specific for the CD3 epsilon chain (KT3), TCR alpha/beta complex (H57-597), and V beta 7 chain (TR310). Tumor cells bristling with these antibodies are capable of inducing murine T-cell proliferation and cytokine production. When injected into growing tumors (P815, RenCa, and B16F10), these constructs induce the activation of immune effector cells and result in the rejection of the tumor. Histological and FACS analysis of tumor-infiltrating leukocytes reveal that the injection of recombinant virus-expressing antibodies specific for the TCR complex attracts and activates (CD25(+), CD69(+)) CD4 and CD8 lymphocytes. This approach represents a novel strategy to overcome T-cell anergy in tumors and allow the stimulation of tumor-specific T cells.  相似文献   

8.
The aim of this study was to investigate means of increasing the efficiency with which cancer cell death following local radiation therapy (RT) is translated into the generation of tumor immunity since, if this were to be achieved, it would be expected to enhance the rates of disease-free recurrence and survival. Our investigations centered around the use of interleukin-3 (IL-3), expressed intratumorally using an inducible adenoviral vector, to alter the immunogenicity of established murine TRAMP-C1 prostate cancer receiving a course of fractionated local RT (7 Gy per fraction per day for 5 days). Because high systemic levels of IL-3 can be associated with toxicity, a tetracycline-regulated gene delivery system was employed. The results show that while intratumoral IL-3 expression or RT alone caused a modest delay in TRAMP-C1 tumor growth, the combination was synergistic with 50% of mice being cured and developing a long-term, tumor-specific state of immunity. Immunological analyses performed on splenic lymphocytes demonstrated that, compared to RT or IL-3 alone, combined treatment significantly increased the number of tumor-specific IFN-gamma-secreting and cytotoxic T cells. The study demonstrates that tetracycline-regulated IL-3 gene expression within tumors can enhance the immune response to prostate cancer and this can augment the efficacy of a course of RT without additional side effects.  相似文献   

9.
High-dose tamoxifen citrate (80 mg/kg), or estradiol (100 micrograms/kg) was administered to intact or castrated Balb/C male and female mice with implanted murine renal cell adenocarcinoma. 100% tumor growth occurred, and tumor weights in tamoxifen treated (mean 3.69 g) and untreated (mean 3.11 g) groups were relatively the same. All estradiol-treated groups had slightly lower tumor weights (mean 2.31 g). This was, however, not statistically significant. Metastases occurred in all groups: control groups had 24-50%, tamoxifen-treated groups had 22-61%, and the estradiol-treated groups had 30-75%. In this murine renal adenocarcinoma model, tamoxifen did not appear to retard tumor growth or metastatic spread.  相似文献   

10.
Forty Balb C/CR mice inoculated with renal cell adenocarcinoma were divided into five groups. Group A (seven animals) received phosphate buffered saline intraperitoneally; group B (seven animals) received free actinomycin D 300 μg/kg IP; group C (nine animals) received lipid vesicles containing actinomycin D 300 μ/kg/kg IP; group D (eight animals) received a mixture of free actinomycin D 300 μg/kg/kg and empty lipid vesicles IP. The median survival of group A was 32 days, of group B 30 days, of group C 45.2 days, of group D 54 days, and of group E 42 days. It is suggested that giving the mixture of the drug and the lipid vesicles produces a balance similar to that found in a vesicle solution containing the actinomycin D. It is also suggested that liposomes slow the absorption of actinomycin D from the peritoneum.  相似文献   

11.
The mitochondria of carcinoma cells retain the permeant cationic compound rhodamine 123 longer than the mitochondria of normal epithelial cells. The possibility of exploiting this difference in the chemotherapy of a murine renal adenocarcinoma was investigated. Rhodamine 123 exhibited anticarcinoma activity in mice and this activity was potentiated by 2-deoxyglucose and methylglyoxal bis(guanylhydrazone), a chemotherapeutic agent that is toxic to mitochondria. Prolonged retention of rhodamine 123 by renal tumor cells compared with normal renal epithelial cells was demonstrated by flow cytometry, perhaps explaining its antitumor activity. A combination of both mitochondrial toxins, rhodamine 123 and methylglyoxal bis(guanylhydrazone) produced the longest survival and had the greatest antitumor effect.  相似文献   

12.

Background:

To characterise recurrence patterns and survival following pathologic complete response (pCR) in patients who received preoperative therapy for localised gastric or gastrooesophageal junction (GEJ) adenocarcinoma.

Methods:

A retrospective review of a prospective database identified patients with pCR after preoperative chemotherapy for gastric or preoperative chemoradiation for GEJ (Siewert II/III) adenocarcinoma. Recurrence patterns, overall survival, recurrence-free survival, and disease-specific survival were analysed.

Results:

From 1985 to 2009, 714 patients received preoperative therapy for localised gastric/GEJ adenocarcinoma, and 609 (85%) underwent a subsequent R0 resection. There were 60 patients (8.4%) with a pCR. Median follow-up was 46 months. Recurrence at 5 years was significantly lower for pCR vs non-pCR patients (27% and 51%, respectively, P=0.01). The probability of recurrence for patients with pCR was similar to non-pCR patients with pathologic stage I or II disease. Although the overall pattern of local/regional (LR) vs distant recurrence was comparable (43% LR vs 57% distant) between pCR and non-pCR groups, there was a significantly higher incidence of central nervous system (CNS) first recurrences in pCR patients (36 vs 4%, P=0.01).

Conclusion:

Patients with gastric or GEJ adenocarcinoma who achieve a pCR following preoperative therapy still have a significant risk of recurrence and cancer-specific death following resection. One third of the recurrences in the pCR group were symptomatic CNS recurrences. Increased awareness of the risk of CNS metastases and selective brain imaging in patients who achieve a pCR following preoperative therapy for gastric/GEJ adenocarcinoma is warranted.  相似文献   

13.
The most serious problem in current gene therapy is that clinical applications have often led to unsatisfactory results. Here we show novel concepts and crucial factors that have been missing for successful cytokine gene therapy. A clinically-relevant mouse model of primary and micro-metastatic osteosarcoma was generated by subcutaneously and intravenously injecting murine osteosarcoma LM8 cells, in which adenoviral gene transduction efficiencies were extremely low; current therapies remain less effective for such disseminated micro-metastases. A single injection of adenoviral vector encoding interleukin-2 gene (Ad.IL-2) was given only into the established primary tumor. Notably, antitumoral immunity was successfully elicited by IL-2 secretion from connective tissues adjacent to the primary tumor, and this immunity not only suppressed primary tumor growth but also eradicated disseminated micro-metastases in distant organs. Most importantly, not only minimal side effects but also maximal therapeutic effects were exerted only in the case of injecting the optimal (i.e., not the highest) dose of Ad.IL-2, because spleen injuries caused by excessive levels of circulating IL-2 might diminish the therapeutic effect. Although the narrow range of the optimal therapeutic expression level of IL-2 may be crucial, it was feasibly determined by serum IL-2 levels. Thus, a crucial factor for successful cytokine gene therapy is not the high gene transduction efficiency in the tumor, which has been generally recommended, but the use of the optimal therapeutic expression level. In conclusion, just a single injection of Ad.IL-2 into a primary tumor lesion, which is feasible, not invasive and cost effective, is potently therapeutic for distant disseminated micro-metastases, as long as the optimal therapeutic level is monitored. These novel concepts, which contradict those of previous studies, warn researches about the possible problems with the ongoing clinical cytokine gene therapy.  相似文献   

14.
15.
肿瘤血管生成及抗血管生成基因治疗   总被引:3,自引:0,他引:3  
肿瘤的侵袭和转移明显影响患者的预后,而肿瘤的血管生成是肿瘤生长、侵袭、转移的基本条件.因而抑制肿瘤血管生成是治疗肿瘤的关键.本文就肿瘤血管生成的调控及抗肿瘤血管生成基因治疗的研究进展作一综述.  相似文献   

16.
董峰  谭建  杨璐  贾强 《实用肿瘤杂志》2005,20(3):228-230
目的研究立体定向放射性核素内照射治疗囊性颅咽管瘤的方法、疗效、安全性及影响预后的因素。方法30例颅咽管瘤患者(囊腔大小平均为20.6cm^3),均采用立体定向穿刺抽液后直接注入^32P胶体的方法进行治疗,给药量”P活度18.5~166.5MBq,平均88.8MBq。通过临床症状观察与复查CT,所有患者进行术后1~3个月及1~4年随访。结果所有患者无手术死亡及严重并发症,早期及1年以上有效率均≥90%,疗效与年龄、性别、初发或复发无明显相关性,而与病情轻重及肿瘤囊腔大小相关。结论立体定向^32P内照射治疗囊性颅咽管瘤方法简便、安全,疗效确切。早期治疗、精确操作、准确估算是治疗成功的关键。  相似文献   

17.
目的 探讨肺腺癌组织特异性自杀基因治疗的安全性及有效性。方法 采用病毒感染法,将癌胚抗原(CEA)基因启动子所驱动的CD基因的组织特异性逆转录病毒载体(G1CEACDNa),导入分泌CEA的肺腺癌细胞系A549细胞.研究裸鼠体内抑瘤效果;应用重组逆转录病毒裸鼠体内治疗A549肿瘤,观察G1CEACDNa/5-氟胞嘧啶(5-FC)对A549细胞致瘤裸鼠的治疗作用及毒副反应。结果 (1)将转基因的A549细胞和未转基因的A549细胞接种至裸鼠皮下.两者成瘤性无明显差异;(2)在转基因细胞致瘤裸鼠实验中,5-FC对转CEA启动子调控自杀基因的肿瘤生长具有明显的抑制作用;(3)将G1CEACDNa重组逆转录病毒上清直接注射到裸鼠成瘤部位.然后腹腔内注射5-FC同样获得明显的抑瘤效果;(4)与直接注射5-FU相比,组织特异性自杀基因治疗对骨髓的抑制明显降低。结论 组织特异性自杀基因治疗可能成为肿瘤治疗个体化的重要方法之一。  相似文献   

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COMBINEDIL2/IL3GENETHERAPYFORG422MOUSEGLIOBLASTOMABYINTRATUMORALINJECTIONOFRECOMBINANTADENOVIRUSES1HongBo2洪波CaoXuetao3曹雪涛Yu...  相似文献   

20.
Topical application of 12-O-tetradecanoylphorbol-13-acetate(TPA) to the dorsal epidermis of Sencar mice induces synthesisof pro-inflammatory cytokines, including interleukin-1  相似文献   

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