Sensitized T lymphocytes render DBA/2 beige mice responsive to IFN α/β therapy of friend erythroleukemia visceral metastases

Interferon α/β (IFN α/β) is highly effective in inhibiting the development of Friend erythroleukemia cell (FLC) visceral metastases in DBA/2 mice injected intravenously (i.v.) with FLC, but does not protect FLC-injected DBA/2 beige (bg/bg) mice. Use of IFN α/β-resistant FLC indicated that IFN was acting through host mechanisms in DBA/2 mice and thus pointed to a defect in some host mechanism in bg/bg mice essential for IFN's anti-metastatic action. We undertook experiments to restore in bg/bg mice the marked anti-FLC meta-static effect of IFN a/p observed in DBA/2 and +/bg mice. Adoptive transfer of spleen cells from normal syngeneic mice to IFN-treated bg/bg mice was ineffective, but the transfer of splenic T lymphocytes from FLC-immunized DBA/2 or +/bg mice markedly increased the survival time of FLC-injected bg/bg mice provided that these mice were also treated with IFN a/p. Neither treatment alone resulted in an increase in survival time. As few as 1 × 10⁷ immune spleen cells were effective in IFN-treated FLC-injected bg/bg mice. The T-cell immune response to FLC of bg/bg mice was diminished compared with that of +/bg mice. Likewise, only combination therapy of immune spleen cells and IFN α/β resulted in an increased survival time of ESb-lymphoma-injected bg/bg mice. Our results indicate the essential participation both of T-cell-mediated immune mechanisms and of IFN α/βin the inhibition of FLC visceral metastases.     

The essential role of endogenous IFN α/β in the anti-metastatic action of sensitized T lymphocytes in mice injected with friend erythroleukemia cells

Adoptive transfer of splenic T lymphocytes from DBA/2 mice immunized against Friend erythroleukemia cells (FLC) inhibited the development of visceral metastases and increased the survival time of DBA/2 mice challenged i.v. with parental FLC 24 hr to 2 months later. Immune spleen cells were ineffective in mice pre-treated with potent neutralizing antibody to mouse IFN α/β (but not to IFN γ), demonstrating the essential participation of endogenous IFN α/β in the inhibitory action of immune T lymphocytes against FLC metastases. These findings suggest that the reported inability of immune T lymphocytes to exert an anti-FLC effect in immunodeficient DBA/2 mutant beige (bg/bg) mice (unless these mice had also been treated with IFN α/β), may have been due to lower levels of endogenous IFN α/β in DBA/2 bg/bg mice than in normal DBA/2 +/bg mice. Experimental results in support of this hypothesis are presented. © 1995 Wiley-Liss, Inc.     

Importance of interferon alpha in the resistance of allogeneic C57B1/6 mice to the multiplication of Friend erythroleukemia cells in the liver

Friend erythroleukemia cells (FLC) (H-2d) injected intravenously multiply extensively in the livers of syngeneic DBA/2 mice and not at all in the livers of allogeneic C57B1/6 mice. Our results indicate that interferon alpha (IFN-alpha) is an important factor in the resistance of allogeneic mice to the multiplication of FLC in the liver. (a) After i.v. inoculation of FLC there was an inverse correlation between the presence of IFN-alpha in the serum and the capacity of FLC to multiply in the liver. Thus, all 44 FLC-injected adult C57B1/6 mice had circulating IFN-alpha and FLC did not multiply in the liver of any of the mice. Interferon was not detected in the serum of 83% of 41 FLC-injected DBA/2 mice (and was found only at a low titer in 17% of the mice) and FLC multiplied in the liver of all mice. (b) FLC did multiply in the livers of newborn C57B1/6 mice and in the livers of irradiated adult C57B1/6 mice, and IFN-alpha was not detected in their sera. In contrast, after i.v. inoculation of FLC, IFN-alpha was detected in the sera of 3-week-old and athymic nu/nu adult C57B1/6 mice while FLC failed to multiply in the liver. (c) FLC also induced IFN-alpha in congenic B10.D2 (H-2d) mice and FLC did not multiply in the liver. We suggest that, depending on the site of tumor implantation, different host mechanisms have various degrees of importance in controlling the growth and/or rejection of allogeneic tumor cells, and that IFN-alpha is particularly important when FLC are injected i.v.     

IFN-α1 gene transfection completely abolishes the tumorigenicity of murine B16 melanoma cells in allogeneic DBA/2 mice and decreases their tumorigenicity in syngeneic C57BL/6 mice

The murine B16 melanoma (H-2^b) was transfected with a retroviral vector containing the mouse IFN-α₁ gene. IFN-α₁-transfected cells produced IFN-α in vitro and exhibited an altered phenotype characterized by a decreased rate of multiplication, enhanced expression of H-2 antigens, an antiviral state to VSV, and decreased pigmentation. Control and IFN-α₁-transfected cells were tested for their ability to grow in syngeneic (H-2^b) CS7B1/6 and allogeneic (H-2^d) DBA/2 mice. IFN-α₁producing B16 clones were less tumorigenic after s.c, i.p., and i.v. routes of injection than IFN-non-producer BI6 clones in syngeneic CS7B1/6 mice. IFN-α₁-producing B16 cells were, however, totally rejected by allogeneic DBA/2 mice regardless of the routes and inocula tested, while control B16 cells grew in and killed DBA/2 mice. The total rejection of IFN-α₁-transfected B16 cells in allogeneic mice appeared to be dependent on T cells as these cells grew in DBA/2 nude mice. Incubation of IFN-α-producing clones with anti-mouse IFN-α/β prior to injection into C57BI/6 mice did not enhance their tumorigenicity. Likewise, injection of C57BI/6 and DBA/2 mice with antibody to IFN-α/β did not enhance the tumorigenicity of IFN-α₁-transfected cells. C57B1/6 mice immunized with irradiated IFN-α₁ cells were only slightly protected against a subsequent challenge with parental B16 cells. In contrast, DBA/2 mice immunized with irradiated IFN-α₁ cells exhibited tumor-specific, long-lasting immunity to subsequent challenge with parental B16 cells. © 1995 Wiley-Liss, Inc.     

Inhibition of mouse alpha/beta-interferon of the multiplication of alpha/beta-interferon-resistant Friend erythroleukemia cells cocultured with mouse hepatocytes

Administration of alpha/beta-interferon (IFN) exerts a marked antitumor effect in DBA/2 mice given injections i.v. of large numbers of IFN-alpha/beta-resistant erythroleukemia cells (FLC). To investigate the possible mechanisms of FLC tumor inhibition in the liver of interferon-treated mice, we developed an in vitro model consisting of a coculture of IFN-alpha/beta-resistant 3Cl8 FLC and syngeneic mouse hepatocytes. Whereas IFN-alpha/beta did not inhibit the multiplication of 3Cl8 FLC cultivated alone, it effectively inhibited the multiplication of 3Cl8 FLC in coculture with hepatocytes. The inhibitory effect was directly proportional to the amount of IFN-alpha/beta added to the cocultures, and more than 90% inhibition of FLC multiplication was noted with 1.6 x 10(5) IU/ml of IFN-alpha/beta on Day 3 of coculture. When FLC were separated from the monolayer of hepatocytes by a pored membrane (0.4 microns), the inhibitory effect on FLC proliferation was unchanged, indicating that a soluble factor(s) released from IFN-treated hepatocytes was most important in the inhibition of FLC multiplication. An inhibitory activity of FLC multiplication was detected only in the conditioned medium of IFN-treated hepatocytes but not in the conditioned medium of control hepatocytes nor in extracts of IFN-treated or control hepatocytes. The inhibitory factor(s) in the conditioned medium of IFN-treated hepatocytes was retained by an ultrafiltration membrane (Mr cut off 10,000), and its activity was completely abrogated by trypsin digestion. Its stability to treatment with 1 M acetic acid as well as lack of correlation between the antiproliferative effect and the amount of L-arginine in the medium distinguished this factor(s) from liver arginase which was also found to be a potent inhibitor of FLC multiplication in vitro. The inhibitory factor(s) was also distinguishable in its biological activity from IFN gamma, interleukin 1 alpha and beta, and transforming growth factor beta 1 and beta 2. These results suggest the possibility that the inhibitory effect of IFN-alpha/beta on the development of 3Cl8 FLC in the livers of IFN-treated mice may be mediated by an IFN-induced inhibitor of FLC multiplication.     

Biologic and biochemical differences between in vitro and in vivo passaged Friend erythroleukemia cells. I. Tumorigenicity and capacity to metastasize

Cloned interferon-sensitive (745) and interferon-resistant (3Cl-8) Friend erythroleukemia cells (FLC) passaged in vitro, are not very tumorigenic when first injected intraperitoneally (i.p.) into syngeneic DBA/2 mice although they do form solid tumors when injected subcutaneously (s.c.). By serially passaging FLC (either 745 or 3Cl-8 cells) i.p. in DBA/2 mice, we obtained two different FLC lines capable of growing i.p. and inducing tumor ascites. The s.c. injection of DBA/2 mice with these in vivo passaged FLC resulted in tumor metastases in the liver and spleen, whereas metastases were not observed in mice inoculated s.c. with in vitro passaged FLC. The capacity of in vivo passaged FLC to metastasize was acquired after several i.p. passages. This highly malignant behavior was a stable characteristic of these cells. All the clones derived from in vivo passaged FLC and passaged more than 14 times in vitro induced hemorrhagic ascites when injected i.p., and metastasized to the liver and spleen when injected s.c. The phenotype of sensitivity or resistance to the inhibitory effect of alpha/beta mouse interferon on virus replication and cell multiplication was conserved during serial i.p. passages and maintained in the clones derived from in vivo passaged cells. These FLC showed a decreased capacity to differentiate in vitro upon treatment with dimethylsulfoxide (DMSO) and a reduced production of Friend leukemia virus with respect to the original clones passaged in vitro.     

Interferon treatment markedly inhibits the development of tumor metastases in the liver and spleen and increases survival time of mice after intravenous inoculation of Friend erythroleukemia cells

To investigate the effect of interferon treatment on the development of tumor metastases, DBA/2 mice were injected i.v. with 2 X 10(6) Friend erythroleukemia cells (FLC) (equivalent to about 5 X 10(5) LD50). FLC multiplied rapidly in the liver and spleen and all untreated or control treated mice died between 7 and 12 days. Daily treatment of mice with potent preparations of mouse interferon alpha/beta was initiated 3 to 72 hr after i.v. inoculation of tumor cells, at times when FLC were already present in the liver and spleen. Interferon treatment resulted in a 100 to 1,000-fold inhibition of the multiplication of FLC in the liver and spleen and a marked increase in mean survival time. Small numbers of tumor cells persisted in the liver and spleen in some interferon-treated mice and could be recovered by bioassay several weeks after tumor inoculation. Most interferon-treated mice died with tumor in the ensuing months. Three of 34 interferon-treated mice were considered cured as they were alive at 386, 325 and 284 days after tumor inoculation. Daily treatment of tumor-inoculated mice with human recombinant interferons alpha D and alpha BDDD, which had antiviral activity on mouse cells in culture, also increased the survival time of mice injected i.v. with FLC. The use of the interferon-resistant 3C18 line of FLC suggests that the marked inhibition of development of established liver and spleen metastases was not due to a direct effect of interferon on the tumor cells, but was host-mediated.     

Anti-tumor effects of interleukin-2 and interleukin-1 in mice transplanted with different syngeneic tumors

We have studied the anti-tumor effects of human recombinant IL-2, alone or in association with LAK cells, in mice transplanted subcutaneously (s.c.) with the following syngeneic tumors: highly metastatic Friend leukemia cells (FLC), nonmetastatic FLC, lymphoma RBL-5 cells and HeJ16 fibrosarcoma cells. In these tumor models, peri-tumoral injections of IL-2 were more effective in inhibiting tumor growth than a systemic treatment. Although s.c. IL-2 treatment resulted in marked inhibition of tumor growth in mice injected s.c. with highly metastatic FLC, it was not effective in inhibiting growth of FLC in the liver and spleen. IL-2 therapy was more effective at increasing survival time in mice transplanted with non-metastatic FLC or with RBL-5 cells. In mice transplanted with HeJ16 fibrosarcomas, s.c. IL-2 treatment resulted in highly significant anti-tumor effect and survival of 70% of tumor-injected mice. No general correlation was found between in vitro sensitivity or resistance to the cytolytic activity of LAK cells and the anti-tumor effects observed in vivo. Subcutaneous injection of IL-1 beta in mice transplanted with highly metastatic FLC resulted in a marked increase in survival time and inhibition of metastatic tumor growth in liver and spleen. Combined treatment of IL-1 beta and IL-2 produced a synergistic anti-tumor effect: 60% of mice injected with highly metastatic FLC survived. Combined IL-1/IL-2 treatments exerted no anti-tumor activity either in DBA/2 mice injected with antibody to Thy 1.2 antigen or in nude mice, indicating that T cells play important roles during IL-1/IL-2 therapy. In vitro treatment of FLC with IL-1 beta resulted in a slight inhibition of cell multiplication, whereas even high doses of IL-2 did not affect FLC multiplication. Our results indicate that local combined treatments with IL-1 and IL-2 can induce potent, host-dependent (T cell-mediated) anti-tumor effects against highly malignant tumors.     

mTOR kinase inhibitor AZD8055 enhances the immunotherapeutic activity of an agonist CD40 antibody in cancer treatment

mTOR is a central mediator of cancer cell growth, but it also directs immune cell differentiation and function. On this basis, we had explored the hypothesis that mTOR inhibition can enhance cancer immunotherapy. Here, we report that a combination of αCD40 agonistic antibody and the ATP-competitive mTOR kinase inhibitory drug AZD8055 elicited synergistic antitumor responses in a model of metastatic renal cell carcinoma. In contrast to the well-established mTOR inhibitor rapamycin, AZD8055 increased the infiltration, activation, and proliferation of CD8(+) T cells and natural killer cells in liver metastatic foci when combined with the CD40 agonist. AZD8055/αCD40-treated mice also display an increased incidence of matured macrophages and dendritic cells compared with that achieved in mice by αCD40 or AZD8055 treatment alone. We found that the combination treatment also increased macrophage production of TNFα, which played an indispensable role in activation of the observed antitumor immune response. Levels of Th1 cytokines, including interleukin 12, IFN-γ, TNFα, and the Th1-associated chemokines RANTES, MIG, and IP-10 were each elevated significantly in the livers of mice treated with the combinatorial therapy versus individual treatments. Notably, the AZD8055/αCD40-induced antitumor response was abolished in IFN-γ(-/-) and CD40(-/-) mice, establishing the reliance of the combination therapy on host IFN-γ and CD40 expression. Our findings offer a preclinical proof of concept that, unlike rapamycin, the ATP-competitive mTOR kinase inhibitor AZD8055 can contribute with αCD40 treatment to trigger a restructuring of the tumor immune microenvironment to trigger regressions of an established metastatic cancer.     

Effects of tamoxifen and interferon-β or the combination on tumor-induced angiogenesis

Inhibition of angiogenesis by anti-tumor agents may play a role in tumor growth arrest. Tamoxifen and interferon-α/β (IFN-α/β) exhibit potentiated anti-proliferative activity against tumor cells. However, additional host-mediated effects such as modulation of angiogenesis may also inhibit tumor growth in vivo. The effect of tamoxifen and IFN-β on angiogenesis induced by 2 human tumors, MCF-7 breast carcinoma (estradiol dependent) and NIH-OVCAR-3 ovarian carcinoma (estradiol independent), was assessed. Treatment of nude mice bearing MCF-7 tumors with tamoxifen resulted in a 68% decrease in the number of vessels at the tumor periphery. Treatment with IFN-β yielded a 33% reduction. Treatment of nude mice bearing NIH-OVCAR-3 tumors with tamoxifen resulted in a 73% decrease in the number of vessels. Treatment with IFN-β yielded a 57% reduction. Combination treatment resulted in augmented anti-angiogenic effects. As single agents, both tamoxifen and IFN-β inhibited xenograft tumor growth. Ten weeks of tamoxifen treatment resulted in growth inhibition of MCF-7 and NIH-OVCAR-3 carcinomas by 85% and 66%, respectively. Ten weeks of IFN-β treatment resulted in inhibition of growth of MCF-7 and NIH-OVCAR-3 carcinomas by 67% and 88%, respectively. The combination of tamoxifen and IFN-β completely prevented growth of MCF-7 and NIH-OVCAR-3 carcinomas. The anti-angiogenic effects of tamoxifen and IFN-β were additive. Inhibition of angiogenesis was detectable before measurable effects on tumor volume in both MCF-7 and NIH-OVCAR-3 tumors. Potentiation of anti-angiogenic effects by tamoxifen and IFN-β, possibly resulting from enhanced IFN-induced gene expression, may contribute to anti-tumor activity in both estradiol-dependent and estradiol-independent tumors in vivo. Int. J. Cancer 71:456-461, 1997. © 1997 Wiley-Liss Inc.     

IFN-β基因诱导裸鼠胶质瘤Fas 表达上调及细胞凋亡的实验研究

 目的 研究β干扰素基因对人脑胶质瘤的诱导凋亡作用,以及能否诱导胶质瘤细胞Fas表达上调,并探讨了β干扰素基因诱导细胞凋亡及Fas表达上调之间的联系. 方法 建立裸鼠SHG44胶质瘤模型,用脂质体包埋法将IFN-β基因的真核表达载体pSV2IFNβ注入裸鼠皮下SHG44脑胶质瘤,观察肿瘤生长情况并计算肿瘤体积,通过免疫组化、TUNEL染色,了解IFN-β基因诱导人脑胶质瘤细胞凋亡的作用以及胶质瘤细胞Fas表达情况. 结果 IFN-β在荷瘤裸鼠瘤体内获得表达,裸鼠皮下胶质瘤生长受到抑制,并诱导SHG44胶质瘤细胞凋亡,胶质瘤细胞Fas表达明显高于对照组. 结论 IFN-β基因能够抑制人脑胶质瘤生长,并诱导胶质瘤细胞凋亡;IFN-β基因诱导胶质瘤细胞凋亡可能是Fas表达上调的结果.     

Expression of retinoic acid α and β receptor genes in liver and hepatocellular carcinoma

cDNA probes for human retinoic acid receptors α and β (RARα and RARβ) were modified for use as specific hybridization probes to study hepatocellular carcinomas (HCC) and cell lines, liver regeneration, and fetal development. RARβ mRNA was detected at low levels in adult liver and rose markedly during the early phase of liver regeneration. RARβ mRNA was present at very low levels in HCC and was not detected in fetal liver. In contrast, RARα mRNA was present at low levels in normal liver, but showed a marked elevation in several HCCs and cell lines. Growth of cell lines was altered by retinoic acid (RA), but the effects could not be predicted by the levels of either RARα or RARβ mRNA. However, the response correlated with cell phenotype. Three cell lines with an adult phenotype (high albumin and low α-fetoprotein) were inhibited by RA, two undifferentiated lines showed moderate growth stimulation, and two of three cell lines that had high levels of α-fetoprotein were markedly stimulated by RA.     

Transforming Growth Factor-β CD4+ T cells Tumor-bearing state Immunosuppression Enhanced Production of TGF-β and a Progressive Increase in TGF-β Susceptibility of Anti-tumor CD4+ T Cell Function

The present study deals with the effect of transforming growth factor-β (TGF-β) on anti-tumor immune responsiveness at various stages of the tumor-bearing state. Spleen cells from BALB/c mice bearing a syngeneic tumor (CSA1M) 1–3 wk after inoculation with CSA1M cells produced interleukin-2 (IL-2) and macrophage-activating factor (MAF)/interferon-γ (IFN-γ) upon in vitro culture without addition of exogenous tumor antigens. This lymphokine production was achieved through collaboration between anti-CSA1M CD4⁺ T cells and antigen-presenting cells that had been pulsed with CSA1M tumor antigens in vivo in the tumor-bearing state. The IL-2-producing capacity of CD4⁺ T cells reached the maximal level as early as one week after tumor implantation but decreased with the progress of tumor-bearing stages. In contrast, the capacity of CD4⁺ T cells to produce MAF/IFN-γ was not affected but was maintained at high levels even late in the tumor-bearing state. The addition of recombinant TGF-β (rTGF-β) to cultures of spleen cells from various tumor-bearing stages resulted in the suppression of lymphokine production. However, the magnitude of the TGF-β-induced suppression varied depending on which tumor-bearing stages of splenic cells were tested as a responding cell population; it was slight in cells from early (1–3 wk) tumor-bearing stages but increased in cells from donor mice at later tumor-bearing stages. Thus, spleen cells from late tumor-bearing stages with weak but significant IL-2-producing and considerable MAF/IFN-γ producing capacities failed to produce these lymphokines when rTGF-β was present in cultures. A progressive increase in the TGF-β susceptibility was also observed for IL-4-producing Th2 as well as IL-2/MAF-producing Th1 cells. In addition, increased levels of TGF-β were detected in plasma from tumor-bearing mice at late stages. Taken together, these results indicate that tumor-bearing mice exhibit enhanced production of TGF-β as well as a progressive increase in the susceptibility of anti-tumor CD4⁺ T cells to TGF-β-induced suppressive mechanisms.     

Normal breast epithelial cells produce interleukins 6 and 8 together with tumor-necrosis factor: Defective il6 expression in mammary carcinoma

Virtually pure primary cultures of normal mammary epithelial cells (MEC) obtained from healthy women were shown to release interleukin 6 and 8 (IL6, IL8) and to produce a non-secreted form of tumor-necrosis factor (TNF). No interferon (IFN), whether α, β or γ, or ILI-α or -β could be detected. Analysis of cellular RNA confirmed these findings and showed that MEC also express IL6 receptor and TNF-α-related mRNAs. Epithelial cells were selectively stained by antibodies to IL6, IL8 and TNF-α both in primary cultures and in the normal mammary gland. Samples of human milk contained sizable amounts of IL6, IL8 and IFN-γ; yet the liquid phase was consistently negative for other cytokines (i.e., TNF-α, IFN-α/-β, ILI-α/-β). Expression of IL6 (but not of IL8 and TNF-α) was abolished in ductal infiltrating carcinomas and greatly reduced in cultures of oncogene-transfected mammary cells, suggesting that alterations of IL6 expression are associated with pathogenesis in breast cancer.     

Anti-tumor effects of interferon in mice injected with interferon-sensitive and interferon-resistant Friend leukemia cells. VI. Adjuvant therapy after surgery in the inhibition of liver and spleen metastases

Adult DBA/2 mice were injected s.c. with the highly malignant, interferon-resistant 3C18 line of Friend erythroleukemia cells (FLC). Eight or 9 days after established s.c. tumors had developed, the primary tumor was excised and mice were treated i.p. with either mouse interferon alpha/beta or a control preparation. At the time of surgery, mice already had tumor cells in the liver. All control-treated mice died in the ensuing 2 weeks with extensive tumor metastases in the liver and spleen. Interferon treatment resulted in an inhibition of the development of liver and spleen metastases and a markedly increased survival time. We conclude that interferon alpha/beta is effective as adjuvant therapy after surgery for metastatic disease in mice.     

转染CD40配体的卵巢癌细胞株OVHM抗卵巢癌肝转移机制的研究

目的 探讨转染CD40配体(CIMOL)的卵巢癌细胞株OVHM(CD40L-OVHM)体内抗卵巢癌肝转移的可能机制.方法 6～8周龄的C57BL/6N×C3H/He杂交一代(B6C3F1)雌性小鼠5只,经小鼠脾脏内接种OVHM,应用HE染色法验证小鼠肝脾转移模型是否建立成功.将OVHM细胞、空载体DNA-pMKITneo-OVHM细胞和CD40L-OVHM细胞接种于B6C3F1小鼠的脾脏,应用流式细胞术,分析荷瘤小鼠脾细胞CD11c分子的表达情况;应用四甲基偶氮唑蓝(MTT)法,检测荷瘤小鼠脾脏细胞毒性T淋巴细胞(CTL)的杀伤活性;应用酶联免疫吸附试验(ELISA),检测荷瘤小鼠外周血血清中干扰素(IFN)-γ、肿瘤坏死因子(TNF)-α、白细胞介素(IL)-12、IL-4和IL-10的含量,并且观察小鼠脾脏和肝脏的成瘤情况及小鼠生存时间.结果 经病理学证实,卵巢癌肝脾转移动物模型建立成功.CD40L-OVHM组中小鼠脾细胞CD11c阳性细胞率明显高于OVHM组和转染空载体DNA-pMKITneo-OVHM组.CD40L-OVHM组小鼠脾脏内CTL的特异性杀伤活性明显增强,小鼠外周血血清中IFN-γ、TNF-α和IL-12的含量明显升高,而IL-4和IL-10的含量则明显降低,与OVHM组和转染空载体DNA-pMKITneo-OVHM组相比,差异均有统计学意义(P<0.05).CD40L-OVHM组小鼠的肝脏和脾脏重量均明显低于OVHM组和转染空载体DNA-pMKITneo-OVHM组,并且小鼠的生存期也明显延长(P<0.05).结论 转染CD40L cDNA的卵巢癌细胞可促进脾脏树突状细胞(DC)的成熟和分化,增强脾脏CTL的特异性杀伤活性,诱导Th1型细胞因子的分泌,抑制Th2型细胞因子的分泌,这可能是CD40L基因体内抗卵巢癌肝转移的机制之一.     

丹参水溶性组分SABP对小鼠肝癌免疫微环境的影响

目的 探讨丹参水溶性组分SABP影响H22细胞肝癌原位移植瘤生长及肝癌免疫微环境的效应。方法 建立H22细胞肝癌原位移植瘤小鼠模型。ELISA检测肝脏中PD-L1、TGF-β、IL-1β、IL-10、IL-4、IFN-γ、IL-18、IL-7、IL-2、CCL-2和CCL-21的表达量。计算肝脏、脾脏和肾脏的脏器系数。结果 SABP抑制H22细胞肝癌原位移植瘤的生长,提高肝癌微环境中PD-L1、TGF-β、IL-1β和IL-10的表达水平,增加了肝、脾和肾系数。结论 SABP能抑制H22细胞肝癌原位移植瘤生长,促进肝癌微环境中PD-L1、TGF-β、IL-1β和IL-10抑制性免疫分子的表达。     

Lymphotoxin‐β receptor activation by lymphotoxin‐α1β2 and LIGHT promotes tumor growth in an NFκB‐dependent manner

Lymphotoxin beta receptor (LTβR) activation on mouse fibrosarcoma cells (BFS‐1) results in enhanced solid tumor growth paralleled by increased angiogenesis induced by the expression of pro‐angiogenic CXCL2. In our study, we demonstrate that both functional ligands of the LTβR, namely LTα₁β₂ and LIGHT, are involved in the activation of LTβR in solid fibrosarcomas. To identify whether the lymphocyte population is involved in the activation of LTβR in these fibrosarcoma tumors, we used conditional LTβ‐deficient mice that specifically lack LTβ expression either on T cells (T‐LTβ^?/?) or on B cells (B‐LTβ^?/?). Solid tumor growth was reduced in both mouse strains when compared to tumor growth in wild‐type mice, indicating the participation of both T and B host lymphocytes in the activation of LTβR in these tumors. Tumor growth was also reduced in LIGHT‐deficient mice, suggesting a contribution of this ligand to the activation of LTβR in BFS‐1 fibrosarcomas. LTβR signaling can involve IκBα and/or NFκB‐inducing kinase (NIK) for subsequent NFκB activation in different types of cells. Expression of a dominant negative form of IκBα or of a dominant negative mutant of NIK resulted in decreased activation of NFκB signaling and reduced expression of pro‐angiogenic CXCL2 in vitro. Moreover, expression of dominant negative form of NIK or an IκBα repressor in these fibrosarcoma cells resulted in reduced solid tumor growth in vivo, suggesting that both IκBα and NIK are involved in pro‐angiogenic signaling after LTβR activation. Our data support the idea that the ablation of LTβR signaling should be considered for cancer treatment.     

Growth inhibition of intracerebral rat glioma by transfection-induced human interferon-β

In our previous study on liposome-mediated transfection of the human interferon-β (HuIFN-β) gene into subcutaneously implanted human gliomas in nude mice, we found that HuIFN-β was produced and secreted by the tumor cells and that the growth of solid tumors was completely inhibited. The present study investigated the growth-inhibitory effect of liposomes containing the HuIFN-β gene inserted into a vector (PSV2IFN-β) on T9 rat glioma implanted into the brains of rats. Tumor cells and liposomes containing pSV2IFN-β or other additives were simultaneously injected into the brains of rats. HuIFN-β was detected in solid gliomas growing in the brains of rats injected with liposomes and magnetic resonance imaging (MRI) showed that tumor growth was inhibited. In addition, the latent period until the appearance of neurological symptoms was significantly prologed in rats treated with liposomes containing pSV2IFN-β. However, the survival time of the treated rats was not significantly increased. © 1995 Wiley-Liss, Inc.     

Expression of β1 integrin receptors in transformed mouse epidermal keratinocytes: Upregulation of α5β1 in spindle carcinoma cells

The adhesive properties and the expression of extracellular matrix receptors of the β1-integrin subfamily were analyzed in transformed epidermal keratinocyte cell lines of different stages of mouse skin carcinogenesis. One- and two-dimensional analyses of the immunoprecipitates obtained with anti-β1- and specific anti-α-integrin subunits showed qualitative and quantitative changes in the expression of β1 integrins by the different cell lines. The polyvalent α3β1 integrin was expressed by all analyzed cell lines, although the levels detected in undifferentiated spindle CarC cells were lower than those present in the rest of keratinocyte cell lines. In contrast, spindle cells expressed high levels of the specific fibronectin receptor α5β1, whereas this integrin was absent or expressed at very reduced levels in the other epithelial cell lines. Expression of α5β1 integrin in spindle cells appeared organized in cell-substratum contact areas on spread cells. In addition, high and homogenous expression of α5β1 was detected in fully undifferentiated tumors induced in nude mice by three independent spindle cell lines. These results suggest that the expression of α5β1 integrin is upregulated during the development of spindle cell carcinomas that occur in the last stages of mouse skin carcinogenesis and can be associated with the acquisition of the fibroblastoid phenotype of spindle cells. On the other hand, expression of the collagen receptor α2β1 was demonstrated in a transformed cell line (PDV), and it was apparently also expressed in two other malignant keratinocyte cell lines (PDVC57 and HaCa4). The expression of α2β1 was correlated with the increased adhesion to collagen type I and Collagen type IV exhibited by the tumorigenic cell lines. © 1995 Wiley-Liss Inc.