Peripheral benzodiazepine receptors in androgen sensitive dunning rat prostatic adenocarcinoma

Several lines of evidence implicate the ras oncogene in tumorigenesis. However, changes in ras oncogene is uncommon in prostate cancer. We evaluated tumors from 55 patients with metastatic prostate cancer (50 lymph nodes, 5 bone metastases), 10 patients with localized cancers and 35 diethylstilbestrol treated primary tumors. Also, 15 patients with benign prostatic hyperplasia and 23 with prostatic intraepithelial neoplasia (PIN) were investigated for ras p21 expression. Avidin biotin immunoperoxidase was used on formalin-fixed, paraffin-embedded tissues with the Pan-ras (Ab-1) monoclonal antibody. Antibody titration demonstrated expression of ras p21 in none of the benign, PIN or DES-treated primary tumor specimens. However, 30% of untreated primary tumors and 94.5% of metastatic tumors (94% of lymph node metastases, 100% of bone metastases) showed expression (p=0.00002). Semi-quantitative evaluation of ras protein expression revealed a significant correlation with Gleason score in lymph node metastases (p=0.001). This study suggests a possible role of ras oncogene in prostate cancer progression, metastasis and androgen independency.     

PC cell-derived growth factor expression in prostatic intraepithelial neoplasia and prostatic adenocarcinoma.

PURPOSE: PCDGF (PC cell-derived growth factor), also called progranulin, is a M(r) 88000 glycoprotein precursor of granulin. It is a novel growth factor that stimulates cell proliferation, confers epithelial tumorigenesis, and promotes tumor invasion. Here we investigate the potential of PCDGF as a therapeutic target for prostate cancer. EXPERIMENTAL DESIGN: We studied the expression of PCDGF in invasive prostate cancer, adjacent high-grade prostatic intraepithelial neoplasia (PIN), and benign prostate tissue from 99 human prostate specimens. The level of PCDGF expression was correlated with various clinicopathological characteristics. RESULTS: Normal prostate tissue did not express (53/99), or expressed low levels (46/99) of PCDGF. In the 46 normal prostate specimens that expressed PCDGF, most of them had less than 10% of cells expressing PCDGF. PCDGF expression could be detected in more than 50% of cells in all specimens of PIN and invasive prostate cancer. The expression of PCDGF in normal prostate tissue was much less intense and in a smaller fraction of cells than in PIN and invasive adenocarcinoma (P < 0.0001). There was no correlation of PCDGF expression with age, Gleason score, pathological stage, status of lymph node metastasis, extraprostatic extension, perineural invasion, surgical margins, and vascular invasion. CONCLUSIONS: Our data suggest that the induction of PCDGF expression occurs during the development of PIN. PCDGF may be a new molecular target for the treatment and prevention of prostate cancer.     

Expression of platelet-derived endothelial cell growth factor in prostatic adenocarcinoma

Angiogenesis is thought to play critical roles in local tumor growth and eventual metastasis. No studies have examined the expression of platelet-derived endothelial cell growth factor (PD-ECGF) in prostatic tissues. Prostatic tissues were obtained from 36 prostatic adenocarcinoma patients. We assessed the expression of PD-ECGF using ELISA and immunohistochemistry. The mean level of PD-ECGF in prostatic adenocarcinomas was higher than that in neighboring normal prostatic tissues in ELISA. Immunohistochemistry showed that the expressions of PD-ECGF, which were associated with increase of microvessel count, were found in the endothelial cells, macrophages, lymphocytes, or fibroblasts. These results suggest that PD-ECGF is involved in the development of prostatic adenocarcinoma.     

Influence of suramin alone or in combination with DHT and PDGF on the cell proliferation of benign and malignant human prostatic tissues in organ cultures.

We studied the suramin-induced influence on the cell proliferation of 16 benign and 6 malignant lesions of the human prostate maintained in vitro as organ cultures. The cell proliferation was assessed by nuclear labeling with tritiated thymidine autoradiography. We also studied the dihydrotestosterone (DHT)-and platelet-derived growth factor (PDGF)-induced modulation of suramin influence on such prostate organ culture cell proliferation. Our results indicate that more than half of the benign prostatic tissues showed cell proliferation which was modulated by DHT and/or PDGF, while none of the six carcinomas responded to such hormonal stimulation. Suramin alone inhibited the cell proliferation of only 19% of the prostate organ culture under study, while in combination with DHT and/or PDGF this inhibition level reached 48%. However, we occasionally observed that S alone or in combination with DHT and/or PDGF was also able to stimulate prostate cell proliferation. We think that organ cultures of human prostatic tissues might represent a helpful pre-clinical tool to study the anti-tumoral influence of suramin, which is a new antineoplastic generative compound.     

Thymidine as an anticancer agent,alone or in combination

Summary The value of thymidine as a cytotoxic drug alone or in combination with other pyrimidine antimetabolites has received considerable attention in recent years.In this paper, the biochemical basis for the cytotoxicity of thymidine and its interaction with other pyrimidine antimetabolites is described. It is indicated that early clinical trials have largely failed to substantiate data from experimental studies that have shown thymidine to be an effective antimetabolite and capable of potentiating the antineoplastic effect of several other agents.It is suggested that tumours likely to respond to thymidine alone or in combination may be identified by measuring in clinical tumour specimens known biochemical determinats of thymidine efficacy.PHE is an Applied Health Fellow of the National Health and Medical Research Council of Australia     

AKT inhibition by triciribine alone or as combination therapy for growth control of gastroenteropancreatic neuroendocrine tumors

Up-regulation of phosphatidylinositol-3-kinase (PI3K)-AKT signaling facilitates tumor cell growth and inhibits cell demise. The AKT-pathway also plays an important role in cytostatic therapy resistance and response to hypoxia and angiogenesis. Using real-time cell proliferation assay we examined the potency of triciribine in three distinct neuroendocrine gastrointestinal tumor cell lines. Also we investigated triciribine's induction of apoptosis and effects on a broad range of cancer-associated gene products. Furthermore, we characterized the role of PTEN as a possible predictor of sensitivity to triciribine in GEP-NETs. We also looked for additive anti-neoplastic effects of triciribine when combined with conventional cytostatic drugs or other targeted drugs, affecting different molecules of the PI3K-AKT-pathway and we assessed the potency of triciribine to inhibit tumor growth in vivo, by using the chick chorioallantoic membrane assay. Treatment of insulinoma (CM) or gut neuroendocrine tumor cells (STC-1) with triciribine significantly reduced tumor cell growth by 59% and 65%, respectively. By contrast, the highly expressing PTEN carcinoid cell line BON did not respond, even at higher doses. Combinations of triciribine with classic cytostatic drugs as well as drugs targeting other molecules of the PI3K-AKT-pathway led to synergistic anti-proliferative effects. Additional in vivo-evaluations confirmed the anti-neoplastic potency of triciribine. Thus, our data show that inhibition the AKT-pathway potently reduces the growth of GEP-NET cells alone or in combination therapies. AKT inhibition may provide a rationale for future evaluations.     

Thrombogenicity of intravenous 5-fluorouracil alone or in combination with cisplatin

Acute myocardial infarction was observed in two patients receiving standard intravenous doses of 5-fluorouracil (5-FU)-based chemotherapy. Therefore, the authors prospectively assessed the thrombogenicity of this agent by studying ten patients, six with head and neck cancer and four with gastrointestinal malignancies, receiving 5-FU (1 g/m2/day) as a constant intravenous infusion over a 4-day or 5-day period. The six patients with head and neck cancer also received a single dose of 100 mg/m2 of cisplatin on day 1. Blood samples were obtained preinfusion, 24 hours into the infusion, and postinfusion. Samples were assayed for fibrinopeptide A (FpA) by enzyme-linked immunoassay, for protein C activity (PCa) using a chromogenic substrate (Spectrozyme PCa), and protein C (PCag) and free protein S antigen (PSag) by electroimmunoassay. No patient experienced a thrombotic event. A significant increase was observed in FpA levels during the infusion which returned toward baseline at the conclusion of the infusion. After infusion of 5-FU, the PCa value was significantly lower than the PCag (37 +/- 17 versus 69 +/- 24%; P less than 0.002). No effect on protein S was observed. The changes in the patients receiving 5-FU alone were comparable to those who also received CDDP. The authors conclude that during the infusion of 5-FU, the rise in FpA activation and reduction in PCa as compared to PCag are compatible with activation of coagulation.     

Invasive potential and substrate dependence of attachment in the dunning R-3327 rat prostate adenocarcinoma model

Cancer cell attachment to and invasion of the extracellular matrix has been associated with the metastatic potential of cell lines of the Dunning R-3327 rat prostatic adenocarcinoma model. We investigated the cell-matrix interactions of prostate tumor cells by comparing the invasive ability through reconstructed extracellular matrix and attachment upon EHS NATRIX (natural extracellular matrix), fibronectin, laminin, and collagen Type IV. We observed a correlation between metastatic potential and substrate dependence of attachment in prostate cancer cells. Nonmetastatic AT-1 cells possessed a higher adhesive potential to extracellular matrix components than the highly metastatic cells (ML, MLL and AT-3). It was also found that the invasive potential of the three highly metastatic cell lines was significantly higher than that of the nonmetastatic cell line. Here, it is reported that the ability to traverse a matrigel matrix correlates with their metastatic potential. These observations suggest that the extracellular matrix components are highly involved in influencing prostate cancer cell activities. In addition, we investigated the effects of two differentiation agents, retinoic acid (RA) and difluoromethylornithine (DFMO), on the adhesive and invasive profiles of the tumor cells. After treatment with both agents, adhesion was increased to levels not different from nonmetastatic cells. Furthermore, the ability of highly metastatic cells to traverse a matrigel barrier was significantly reduced after treatment with both differentiation agents. These results suggest that RA and DFMO are capable in reversing the metastatic potential of prostate cancer cells in vitro and may give a possible insight into their role as potential therapeutic agents in vivo.     

Influence of Tamoxifen or the combination of Tamoxifen and Cisplatin on the growth of human lung adenocarcinoma A549 cells

The experiment aims to investigate the influence of Tamoxifen and the combination of Tamoxifen and Cisplatin （DDP） on the growth of human lung adenocarcinoma A549 cells. Methods： We treated human lung adenocarcinoma A549 cells with different concentrations of Tamoxifen, DDP and combination of DDP and Tamoxifen with non-toxicity for 72 h. Then we calculated the inhibition rate through MTT approach and detected the apoptosis rate by flow cytometry. The statistical analysis was performed with SPSS 13.0 software and statistical differences were determined by one-way ANOVA. The data were expressed as the mean ＋ standard deviation and all experiments were performed in three times. The value of P 〈 0.05 was considered to indicate a statistically significant difference. Results： 1. The inhibition rates of Tamoxifen with 2.5 pmol/L, 5 tJmol/L, 10 μmol/L, and 20 μmol/L on the growth of the A549 cells were 18.7%, 25.8%, 54% and 98.8%, respectively （P = 0.000）. Tamoxifen with concentration of 1 μmol/L has no obvious cytoxicity on the A549 cells （P 〉 0.05）. 2. As the increase concentration of Tarnoxifen, the S stage and G2/M of the A549 cells decreased while the G0/G1 increased. The apoptosis rate of Tamoxifen with 0 μmol/L, 0.1 μmol/L, 1 μmol/L and 10 μmol/L on the A549 cells were 6.51%, 8.91%, 17.97% and 42.7%, respectively. 3. The inhibition rates of combination of Tamoxifen with 1 μmol/L and DDP with 1.25 μg/mL, 2.5 μg/mL, 5 μg/mL, 10 μg/mL and 20 μg/mL on the A549 cells were 40.4%, 54.4%, 72.9%, 86.1% and 92.4%, respectively （P 〈 0.05）. Conclusion： Tamoxifen can inhibit the proliferation of human lung adenocarcinoma A549 cells and induce the apoptosis of the A549 cells. The combination of Tamoxifen with non-toxicity and DDP can improve the sensitivity of chemotherapy on the A549 cells.     

Biweekly high-dose gemcitabine alone or in combination with capecitabine in patients with metastatic pancreatic adenocarcinoma: a randomized phase II trial.

BACKGROUND: Gemcitabine is an active antitumor agent in the treatment of advanced pancreatic cancer, and has shown potential synergistic activity with the oral fluoropyrimidine capecitabine in previous phase I/II trials. Based on this background and in order to define the therapeutic potential and tolerance of this combination more precisely, the present randomized multicenter phase II trial was initiated. PATIENTS AND METHODS: We prospectively randomized 83 patients to treatment with biweekly gemcitabine 2,200 mg/m(2) given as a 30 min intravenous infusion on day 1, or the same treatment plus oral capecitabine 2,500 mg/m(2) given from days 1 to 7. In both arms, chemotherapy was administered for a duration of 6 months unless there was prior evidence of progressive disease. The efficacy of the two treatment arms was evaluated according to standard criteria, i.e. objective response, progression-free survival (PFS) and overall survival (OS), as well as by analysis of clinical benefit response. RESULTS: The overall objective response rate among the 42 patients treated with gemcitabine alone was 14% compared with 7/41 (17%) among those treated with the combination arm. Similar to response rates, there was no apparent difference between the two groups in terms of median PFS (4.0 versus 5.1 months) and median OS (8.2 versus 9.5 months) in the gemcitabine and combination arm, respectively. Of 61 patients with tumor-related symptoms, who were considered evaluable for clinical benefit response, 10/30 (33%) and 15/31 (48.4%) experienced significant palliation in the gemcitabine and combination arm, respectively. Chemotherapy was well tolerated in both arms with only four versus six patients experiencing WHO grade 3 symptoms. Apart from the occurrence of hand-foot syndrome in 10 patients, no major increase in incidence and/or degree of adverse reactions was noted in the combination arm. CONCLUSIONS: Results of this trial suggest a fairly good therapeutic index for the combination of biweekly high-dose gemcitabine and capecitabine for the treatment of advanced pancreatic cancer. Despite a somewhat superior clinical benefit response rate, no advantage over single-agent gemcitabine, however, was noted in terms of objective efficacy parameters.     

Androgenic regulation of growth factor and growth factor receptor expression in the CWR22 model of prostatic adenocarcinoma.

The effects of androgen manipulation on epidermal growth factor (EGF) receptor, p185erbB-2 and transforming growth factor-alpha (TGF-alpha) levels were examined in prostatic adenocarcinoma. Male nude mice were inoculated with the CWR22 androgen-dependent human prostatic tumor or an androgen-independent (CWR22R) derivative. Mice with CWR22 tumors were castrated and subsequently killed at 3, 7, 21, 28 or 42 days post-castration. Other CWR22-bearing mice received s.c. testosterone pellets at 21 days post-castration and were killed 7 days later. EGF receptor, p185erbB-2 and TGF-alpha levels were examined by immuno-histochemistry. Strong EGF receptor and p185erbB-2 immunostaining was detected in CWR22 tumors from intact controls. EGF receptor immunostaining decreased by 65% to 70% at 21 to 42 days post-castration. Testosterone treatment at 21 to 28 days post-castration resulted in a 2-fold increase in EGF receptor immunostaining. p185erbB-2 immunostaining within CWR22 tumors did not decrease following castration and, in fact, was slightly increased at 7 days post-castration. The effects of castration on EGF receptor and p185erbB-2 levels were confirmed by Western blot analysis. Fewer than 10% of CWR22 tumor cells demonstrated strong TGF-alpha immunostaining, and androgen manipulation did not effect TGF-alpha immunostaining. In contrast, 30% of androgen-independent CWR22R tumor cells were strongly immunostained for TGF-alpha. Our findings indicate that EGF receptor levels, but not p185erbB-2 levels, are strongly dependent on testosterone in CWR22 tumors. The co-localization of TGF-alpha and the EGF receptor in CWR22R tumors suggests that these factors may constitute an autocrine pathway that regulates androgen-independent growth.     

抗促胃液素疫苗mG17-CRM197单用及联合5-FU抑制小鼠结肠癌的生长

目的：观察抗促胃液素(gastrin,又称胃泌素）疫苗mG17-CRM197（mG17）单用及联合氟尿嘧啶（fluorouracil,5-FU）对小鼠结肠癌C38移植瘤的抑制作用。方法：采用Western blotting法检测结肠癌细胞促胃液素受体（CCKBR）的表达情况,磺酰罗丹明B（SRB）法检测mG17-NH2对C38细胞增殖的影响。C57BL/6小鼠随机分为PBS组、CRM197组、mG17组、5-FU组和mG17/5-FU组,ELISA法检测小鼠血清中抗G17抗体水平;免疫后的小鼠皮下进行肿瘤移植,5-FU组和mG17/5-FU组给予5-FU（20 mg/kg,q2d×5）,其他组给予生理盐水,通过肿瘤生长曲线和瘤质量评价不同治疗方案对C38移植瘤生长的影响。结果：小鼠结肠癌C38细胞表达CCKBR,mG17-NH2浓度依赖性上调CCKBR的表达,且能促进 C38细胞增殖（细胞增殖率为115.7%~133.5%）。mG17疫苗免疫3次后,小鼠血清抗mG17抗体水平依次升高。mG17组、5-FU组和mG17/5-FU组对C38移植瘤有显著抑制作用,抑瘤率分别为58.0%、60.5%和80.7%;按金氏法计算,mG17与5-FU联用的Q值为0.97,两药联用出现相加作用。结论：mG17-CRM197疫苗对小鼠结肠癌C38移植瘤治疗有效,与5-FU联用增强对小鼠结肠癌的抑制。     

Radiation therapy alone or in combination with surgery in the treatment of carcinoma of the esophagus

The role of radiation in the treatment of squamous cell carcinoma of the esophagus was examined in a review of 74 patients treated with curative intent between 1974 and 1981. Aspects studied included the pattern of failure, the use of radiation as a surgical adjuvant, achievement of palliation, and the presence of technical or clinical factors predicting for a better outcome. The group was divided into 9 patients irradiated after esophageal resection, 14 patients irradiated before resection, and 51 patients treated with radiation and no resection. Median and 2-year survival rates among 51 patients treated by radiation without esophagectomy were 8.8 months and 11%, whereas they were 9.7 months and 0% in patients treated by radiation followed by resection, and 9.5 months and 28% in patients undergoing resection followed by radiation. Local failures were suffered in 28/51 patients treated without esophagectomy with rates of 2/4, 7/10, 7/15, and 5/10 after 50-55 Gy, 55-60 Gy, 60-65 Gy, and 65-69 Gy, respectively. Although prognosis for patients presenting with unresectable disease remains poor, a somewhat better outcome may be expected in patients treated with postoperative radiation after potentially unfavorable resections. Other predictors include sex and disease stage.     

Interleukin-2 and histamine in combination inhibit tumour growth and angiogenesis in malignant glioma

Biotherapy including interleukin-2 (IL-2) treatment seems to be more effective outside the central nervous system when compared to the effects obtained when the same tumour is located intracerebrally. Recently published studies suggest that reduced activity of NK cells in tumour tissue can be increased by histamine. The present study was designed to determine whether IL-2 and histamine, alone or in combination, can induce anti-tumour effects in an orthotopic rat glioma model. One group of rats was treated with histamine alone (4 mg kg(-1)s.c. as daily injections from day 6 after intracranial tumour implantation), another group with IL-2 alone as a continuous subcutaneous infusion and a third group with both histamine and IL-2. The animals were sacrificed at day 24 after tumour implantation. IL-2 and histamine in combination significantly reduced tumour growth. The microvessel density was significantly reduced, an effect mainly affecting the small vessels. No obvious alteration in the pattern of VEGF mRNA expression was evident and no significant changes in apoptosis were observed. Neither IL-2 nor histamine alone caused any detectable effects on tumour growth. Histamine caused an early and pronounced decline in tumour blood flow compared to normal brain. The results indicate that the novel combination of IL-2 and histamine can be of value in reducing intracerebral tumour growth and, thus, it might be of interest to re-evaluate the therapeutic potential of biotherapy in malignant glioma.     

BRAF and KRAS mutations in prostatic adenocarcinoma

Constitutive activation of the kinase cascade involving RAS, RAF, MEK and ERK is common to human cancers, and mutations of KRAS and BRAF are mutually exclusive and serve as alternatives to activate the RAS/RAF/ERK signaling pathway. RAS mutations are known to occur in prostate adenocarcinomas, but little is known about BRAF mutations in these tumors. In the present study, BRAF and KRAS mutations were characterized in 206 prostate adenocarcinomas by enhanced PCR-RFLP and direct sequencing. The identified KRAS and BRAF mutations were then analyzed with respect to preoperative serum PSA levels, Gleason scores and tumor stages. Mutations in codon 600 of BRAF were identified in 21 (10.2%) of 206 prostate adenocarcinomas. KRAS mutations in codons 12 or 13 were found in 15 (7.3%) of 206 prostate adenocarcinomas. However, no tumor specimen contained both BRAF and KRAS mutations. Prostate adenocarcinomas with a BRAF mutation tended to show higher preoperative serum PSA levels, Gleason scores and tumor stages than prostate adenocarcinomas with a KRAS mutation. The results obtained show that BRAF mutations are as uncommon as KRAS mutations in prostate adenocarcinoma. Although BRAF and KRAS are members of the same RAS/ERK signaling pathway, prostate adenocarcinomas with a BRAF mutation showed clinicopathologic features that differed from those of prostate adenocarcinoma with a KRAS mutation.     

C225单用及与DDP联用对宫颈癌裸鼠移植瘤生长的抑制作用

目的: 探讨C225单用及与DDP联用对人宫颈癌HeLa细胞裸鼠移植瘤生长抑制作用的机制.方法: 将40只人宫颈癌HeLa细胞株的裸鼠移植瘤模型随机分为对照组、C225组、DDP组和C225+DDP组,每组各10只.各组裸鼠分别经腹腔注射质量分数为0.9%的氯化钠溶液、C225(1 mg·只-1·次-1)、DDP(5 mg·kg-1·次-1)和C225+DDP,每周2次,共4周.实验结束时,将移植瘤完整取出,测量瘤体体积,计算抑瘤率;镜检移植瘤组织和细胞形态变化,应用免疫组织化学技术检测2药单用及联用后对p27Kip1、cyclin D1在宫颈癌HeLa细胞裸鼠移植瘤组织中表达的影响.结果: C225组、DDP组和C225+DDP组的体积抑瘤率分别为37.14%、46.96%和69.32%;镜下可见对照组的癌细胞生长旺盛,异型性高,而各治疗组的肿瘤细胞不同程度减少,间质增加,DDP组与C225+DDP组可见瘤组织大量坏死,联用组尤甚.免疫组织化学结果显示,p27Kip1的表达率在C225组与C225+DDP组较对照组显著提高(P<0.01,P<0.05),DDP组与对照组结果一致.cyclin D1的表达率经C225单用及与DDP联用后较对照组显著降低(P<0.05,P<0.01),而DDP组与对照组间差异无统计学意义(P0.05).结论: C225可能通过上调p27Kip1水平,并抑制cyclin D1表达来影响宫颈癌裸鼠移植瘤的生长;C225和DDP联合用药的抑瘤率高于单一用药,可能和C225能提高DDP的敏感性有关.     

Sunitinib malate (SU-11248) alone or in combination with low-dose docetaxel inhibits the growth of DU-145 prostate cancer xenografts

The aim of the study was to evaluate the activity of the antiangiogenic agent SU-11248 (sunitinib malate, Sutent^®), alone or in combination with docetaxel. To this end, animals bearing DU-145 human hormone-refractory prostate cancer (HRPC) xenografts were treated with sunitinib (40 mg/kg daily, p.o.), docetaxel (10 or 30 mg/kg/week, i.v.), a combination of sunitinib (40 mg/kg daily) and docetaxel (10 mg/kg/week) or vehicle alone. At the end of the 3-week dosing schedule, single-agent treatment induced a tumor regression of 59%, 49% and 75% for sunitinib, docetaxel 10 mg/kg, and docetaxel 30 mg/kg, respectively. The combination of sunitinib with low-dose (10 mg/kg) docetaxel produced a tumor regression comparable to that obtained with high-dose (30 mg/kg) docetaxel, but tolerability was higher as indicated by mice weight. Both sunitinib and docetaxel inhibited tumor regrowth after initial treatment with the alternate drug. These results suggest that sunitinib alone or in combination with low-dose docetaxel may have a role in the treatment of HRPC.     

Lipoteichoic acid of Bifidobacterium in combination with 5-fluorouracil inhibit tumor growth and relieve the immunosuppression

To investigate the therapeutic efficacy of lipoteichoic acid of Bifidobacterium (BLTA) in combination with 5-fluorouracil (5-FU) treatment on the mice bearing inoculated hepatoma-22 (H₂₂) cells and the effects of BLTA on immunological regulation of organism, and explore its mechanisms.MethodsTumor-bearing mice were treated with 5-FU alone, BLTA alone or BLTA in combination with 5-FU. The tumor size were observed and measured regularly. The growth inhibiting rate (IR) of tumor was detected. MTT assay was used to evaluate the proliferation of T lymphocytes and splenic NK cell and CTL activity. Enzyme linked immunosorbent assay (ELISA) was used to detect the change of IFN-Γ. FCM was used to detect T subgroup ratio of spleen cells of tumor-bearing mice. Expression change of mRNA and proteins of Foxp3 and TIM-3 were detected by Real-Time-PCR and Western blot in tumor-bearing mice tumor tissue.ResultsBoth 5-FU and BLTA had inhibition effect on tumor-growth. While in the 5-FU + BLTA group, the inhibition of tumor growth was more significant, with increased T lymphocyte proliferation and IFN-Γproduction of spleen cells. Spleen cells of tumor-bearing mice had high CD4⁺CD25⁺regulatory T cell (CD4⁺CD25⁺T_reg) ratio and high mRNA and proteins expression of Foxp3 and TIM-3, but in the BLTA and 5-FU group, CD4⁺CD25⁺T_reg ratio degraded, with down regulation mRNA and proteins expression of Foxp3 and TIM-3. But CD4⁺ T cells also decreased in spleen cells of tumor-bearing mice by alone 5-FU treated, splenic NK cell and CTL activity also degraded, while CD4⁺ T cells and splenic NK cell and CTL activity significantly increased by BLTA treated. BLTA in combination with 5-FU could also enhance the ratio of CD4⁺ T cells and splenic NK cell and CTL activity.ConclusionThe present study suggested that BLTA in combination with 5-FU could enhance antitumor effect, with inhibiting TIM-3/TIM-3L pathway, cutting down immunosuppressive activity of CD4⁺CD25⁺ T_reg and enhancing cell-mediated immunity.     

Increases in tumor response by pentoxifylline alone or in combination with nicotinamide.

Pentoxifylline (PENTO), a derivative of methylxanthine, has been reported to improve fluidity of red blood cells (RBC), and thus improve the flux of RBC through narrow capillaries. Additionally, PENTO increases 2,3-DPG levels in RBC, thereby increasing the O2 release from RBC. Nicotinamide (NA) has been known to increase tumor blood flow, reducing the hypoxic cell fractions in the tumors. The purpose of this study was to examine the effects of PENTO alone or in combination with NA (PENTO + NA) on the oxygenation and radio-response of FSaII murine fibrosarcomas of mice. We observed a significantly enhanced, radiation-induced growth delay of the FSaII tumors by the treatment of either single or multiple injections of PENTO. The combination of PENTO and NA further delayed the growth of tumors. The TCD50 of control tumors was about 56.6 Gy, whereas that of PENTO + NA treated tumors was about 31.9 Gy. Thus, TCD50 was modified by a factor of 1.8. PENTO + NA exerted no effect on the acute skin damage of C3H mice after local irradiation and the gastrointestinal death after whole body irradiation. However, PENTO + NA slightly increased the bone marrow death as demonstrated by the decrease in LD50(30) from 5.5 Gy to 5.2 Gy. The average pO2 in the saline-treated control group of FSaII tumors was 8 mmHg and it significantly increased to 19 mmHg in the PENTO + NA treated group (p less than 0.001). We concluded that the PENTO + NA treatment increased the radio-response of tumors by improving tumor oxygenation.