PEG-IL-2 therapy of advanced cancer in the guinea pig. Impact of the primary tumor and beneficial effect of cyclopphosphamide

The efficacy of tumor therapy using polyethylene-glycolmodified interleukin-2 (PEG-IL-2), alone or in combination with cyclophosphamide, was studied in advanced metastatic disease in the guinea pig. Line 10 (L10) tumor cells appeared in the axillary lymph node only 7 days after intradermal tumor-cell inoculation, and lymph-node leukocytes were almost completely replaced by tumor cells on day 28. Local treatment of the intradermally growing L10 hepatocarcinoma in the guinea pig with a relatively low dose of PEG-IL-2 resulted in regression of the primary tumor and prevention of lymph-node metastases. Therapy was completely curative (4 out of 5 animals) when started on day 7 or 14 after tumor-cell inoculation. When started on day 21, therapy was effective in only some (2 out of 5 cured) of the treated animals. Anti-tumor effects against the primary tumor and against lymph-node metastases were observed only after intratumoral (i.t.) administration of PEG-IL-2. Injection of the agent into or near lymph-node metastases in the absence of the primary tumor had no curative effect. In PBS/BSA-treated control animals the primary tumor and metastases grew progressively. In the treatment of far advanced metastatic disease, the combination of i.t. administration of PEG-IL-2 and i.p. injection of cyclophosphamide (Cy) resulted in improved anti-tumoral effects (5/5 guinea pigs were cured) when compared with monotherapy using either agent (one and none out of 5 animals cured, respectively). PBS/BSA heated controls showed progressive tumor-growth. We conclude that large primary tumors and lymph-node metastases can be treated effectively with PEG-IL-2. The i.t. route of administration is of major importance in the treatment of metastases, since administration of PEG-IL-2 near or into the lymph node had no therapeutic effect. Combination of PEG-IL-2 therapy with systemic injections of Cy significantly improved the curative effects of the treatment of advanced metastatic cancer.     

Pharmacokinetics and toxicity of intrathecal administration of recombinant interleukin 2

In order to contribute to the development of adoptive immunotherapy against malignant brain tumors, the pharmacokinetics and toxicity of intrathecally administered recombinant interleukin-2 in dogs and human patients were analyzed. The pharmacokinetics showed that a high concentration of IL-2 was maintained in the intrathecal cavity in both dogs and human (t1/2 = 1.41 and 1.68 hours, respectively) after administration. However, no activity of IL-2 was detected in the cerebrospinal fluid after the systemic administration of rIL-2 in one dog. No meningitis, ventriculitis or degeneration of neurons was seen histopathologically in dogs 3 weeks after the intrathecal administration of rIL-2 (200 units). A high concentration of IL-2 in the tumor cavity was maintained for a very long time (t1/2 = 14.8 hours) after the intratumoral administration of rIL-2 in one of the patients. Although low-grade fever and mild headache were sometimes observed after the intrathecal administration of rIL-2 in patients, there was no other side effect mentioned. Intrathecal or intratumoral administration of rIL-2 appeared to be an valuable procedure which should be evaluated in conjunction with adoptive immunotherapy against malignant brain tumors.     

Angiosarcoma of the scalp treated with curative radiotherapy plus recombinant interleukin-2 immunotherapy

PURPOSE: To evaluate the effectiveness of curative radiotherapy (RT) plus recombinant interleukin-2 (rIL-2) immunotherapy regarding the treatment results for angiosarcoma of the scalp. Curative resection of angiosarcoma of the scalp is usually difficult because of the diffuse, clinically undetectable local spread. RT is a rational therapeutic approach, because a wide region of the dermis can be treated, while sparing the underlying normal tissues. Recently, the effectiveness of immunotherapy with rIL-2 has also been reported in the treatment of angiosarcoma of the scalp. METHODS AND MATERIALS: The data of 20 patients with angiosarcoma of the scalp treated with curative RT plus rIL-2 immunotherapy between January 1988 and June 2002 were retrospectively analyzed. The total radiation dose was 70.3 +/- 6.9 Gy. The fractions were 2-3 Gy daily, given 5 d/wk. rIL-2 immunotherapy was performed by transcatheter arterial administration in 10 patients, systemic administration in 11 during the course of RT, and intratumoral injection in 10 during and/or after RT; 12 patients received a combination of two. Five patients underwent limited surgery, and concomitant pacilitaxel chemotherapy was also used in 2 patients. RESULTS: The median survival time for overall, local recurrence-free, and distant metastasis-free survival was 36.2, 11.1, and 17.8 months, respectively. Local recurrence developed in 7 patients (35%), 4 of whom also had evidence of distant metastases. An additional 7 patients (35%) developed distant metastases alone. Recurrence within the radiation field was recognized in 2 patients with systemic rIL-2 administration alone (p < 0.05). Arterial or intratumoral administration combined with systemic administration of rIL-2 resulted in better distant metaststasis-free survival rates (p < 0.05). CONCLUSION: Curative RT plus rIL-2 immunotherapy provided an efficient, effective means of treating angiosarcoma of the scalp. Arterial or intratumoral administration combined with systemic administration of rIL-2 may prolong survival. Additional studies with detailed treatment protocols are recommended.     

Local adoptive immunotherapy of human head and neck cancer xenografts in nude mice with lymphokine-activated killer cells and interleukin 2

The efficacy of local adoptive immunotherapy with human lymphokine-activated killer cells and recombinant interleukin 2 (rIL-2) in growth inhibition of established squamous cell carcinoma of the head and neck (SCCHN) was evaluated in a nude mouse model. The model of xenografted SCCHN was established by s.c. injections of in vitro maintained tumor cells (2-10 x 10(6) cells/mouse) into the flank of splenectomized animals pretreated with cyclophosphamide (200 mg/kg). The SCCHN line used was tumorigenic in 95% of the appropriately conditioned nude mice. Inhibition of tumor growth by locally administered effector cells was the end point of the study, since the tumors did not metastasize within 6 weeks of tumor challenge. Either i.p. or local administration of rIL-2 alone (1000 units/day) to the tumor site daily for 2 weeks resulted in a significant inhibition of tumor growth. In the absence of detectable natural killer activity in these mice, a modest dose of rIL-2 had a direct antitumor effect on SCCHN cells in vivo. In addition, complete inhibition of tumor growth was achieved with 3 times weekly injections of 5-10 x 10(6) lymphokine-activated killer cells delivered to the tumor site and 1000 units of rIL-2 administered locally every day for 2 weeks. Our data indicate that local or systemic immunotherapy with rIL-2 alone or local adoptive immunotherapy with an adequate dose of lymphokine-activated killer cells plus rIL-2 may be effective in preventing the growth of established SCCHN tumors in vivo.     

Antitumor effect of interleukin-1 beta in the double grafted tumor system

The antimetastatic effect of recombinant human interleukin-1 beta (rIL-1 beta) in a new experimental mouse model was studied. Intratumoral administration of IL-1 beta strongly inhibited the growth of Meth-A solid tumors in male BALB/c mice and led to a complete regression of tumors and resistance to reinoculated tumor. Subsequently, the anti-metastatic effect of IL-1 beta was examined in the double grafted tumor system, in which mice first received simultaneous intradermal inoculations of Meth-A in both right (10(6) cells) and left (2 X 10(5) cells) flanks and were then injected with 0.2 micrograms of IL-1 beta in the right tumor on days 3, 4 and 5. IL-1 beta significantly inhibited the growth of the left, non-treated tumor. When mice received only an inoculation of Meth-A (2 X 10(5) cells) in the left flank and were injected subcutaneously with IL-1 beta into the right flank on day 3 (single tumor system), there was no inhibition of the growth of the left, non-treated tumor. These findings suggest that intratumoral IL-1 beta immunotherapy in one region has an effect on tumor growth in another region. Immunized spleen cells were taken from mice which had been cured by the intratumoral administration of IL-1 beta. Adoptive transfer of the immunized spleen cells caused the complete regression of Meth-A tumors. These results suggest that intratumoral administration of IL-1 beta might induce cytotoxic cells in the left non-treated tumor of the double grafted tumor system and bring about the regression of metastatic tumors.(ABSTRACT TRUNCATED AT 250 WORDS)     

Antitumor Effect of Interleukin-1β in the Double Grafted Tumor System

The antimetastatic effect of recombinant human interleukin-1β (rIL-1β) in a new experimental mouse model was studied. Intratumoral administration of IL-1β strongly inhibited the growth of Meth-A solid tumors in male BALB/c mice and led to a complete regression of tumors and resistance to reinoculated tumor. Subsequently, the anti-metastatic effect of IL-1β was examined in the double grafted tumor system, in which mice first received simultaneous intradermal inoculations of Meth-A in both right (10⁶ cells) and left (2×10⁵ cells) flanks and were then injected with 0.2 μg of IL-1β in the right tumor on days 3, 4 and 5. IL-1β significantly inhibited the growth of the left, non-treated tumor. When mice received only an inoculation of Meth-A (2×10⁵ cells) in the left flank and were injected subcutaneously with IL-1β into the right flank on day 3 (single tumor system), there was no inhibition of the growth of the left, non-treated tumor. These findings suggest that intratumoral IL-1β immunotherapy in one region has an effect on tumor growth in another region. Immunized spleen cells were taken from mice which had been cured by the intratumoral administration of IL-1β. Adoptive transfer of the immunized spleen cells caused the complete regression of Meth-A tumors. These results suggest that intratumoral administration of IL-1β might induce cytotoxic cells in the left non-treated tumor of the double grafted tumor system and bring about the regression of metastatic tumors. On the other hand, recombinant tumor necrosis factor was effective only on the treated, right tumor, having no effect on the distant, left tumor in the double grafted tumor system. Recombinant interleukin-2 was effective on neither the right tumor nor the left tumor in this system. These results show that there are major differences of antitumor mechanism among cytokines.     

Inhibition of tumor growth by the intralesional administration of interleukin-3 into mice implanted with solid tumors.

The antitumor activity of three interleukin-3 (IL-3) preparations administered intralesionally into mice bearing syngeneic solid tumors was investigated. IL-3 preparations used in this study included S-IL-3, which was isolated from the culture fluid of murine inguinal lymph node cells stimulated with an arabinomannan extracted from Mycobacterium tuberculosis (SSM), the culture fluid of WEHI-3 cells (W-IL-3) and recombinant IL-3 (rIL-3). When a 1,500 U/kg dose of S-IL-3 or W-IL-3 was injected intralesionally into BALB/c mice bearing Meth-A solid tumors three time per week beginning 3 days after tumor inoculation, tumor growth was inhibited by 60% or 74% at 24 days after tumor inoculation, respectively. In these experiments, 1 unit of IL-3 activity was determined to be the concentration that induced 50% of maximal proliferation of an IL-3 dependent cell line (FCD-P2 cells). The administration of this dose of rIL-3 inhibited tumor growth by 34%. When these three preparations of IL-3 were pretreated with anti-IL-3 monoclonal antibody in vitro, the antitumor activity, as well as their growth promoting activity on FDC-P2 cells, was eliminated. Since direct cytotoxic activities of these IL-3 preparations against cultured Meth-A tumor cells in vitro have not been demonstrated, these results suggest that their antitumor activities might be expressed through interactions between tumor cells and antitumor effector cells which were stimulated by the intralesional administration of the IL-3 preparations.     

Antitumor effects of polyethylene glycol-modified recombinant human interleukin-2 on mouse uterine cervical carcinomain vivo

Polyethylene glycol (PEG-8000)-modified recombinant human interleukin-2 (PEG-rIL-2) is a cytokine with prolonged circulatory half-life. In this paper, the antitumor effects of PEG-rIL-2 against mouse uterine cervical carcinoma (U₁₄) transplanted intraperitoneally or subcutaneously is reported. PEG-rIL-2 at different doses was administered intraperitoneally. The results showed that PEG-rIL-2 (4500 IU, i.p., QD×5) prolonged survival time of mice bearing ascites tumor as compared to rIL-2 (P<0.01), but PEG-rIL-2 at lower doses was without therapeutic effect In addition, compared to rIL-2, PEG-rIL-2 at different doses (1500–13500 IU, s.c, QD×5) caused significant dose-dependent growth inhibition of solid tumor (P<0.01) when the treatment started at day 4 after subcutaneous inoculation of tumor.     

Adoptive immunotherapy for recurrent glioblastoma multiforme using lymphokine activated killer cells and recombinant interleukin-2

Thirteen patients with recurrent glioblastoma were treated with adoptively transferred autologous lymphokine activated killer (LAK) cells and recombinant interleukin-2 (rIL-2). Patients' blood mononuclear cells (MNC) obtained by leukapheresis were cultured at 2.5 million MNC per ml for 3 to 5 days in media containing 1000 U rIL-2/ml. After incubation, the nonadherent MNC from all cultures (0.5-5 X 10(9] were combined and concentrated for infusion in 5 to 10 ml saline containing 10(6) U rIL-2. Nine patients received one injection of LAK cells and rIL-2 into the brain tissue immediately surrounding the tumor cavity during craniotomy for subtotal tumor removal (Group 1). On each of the 3 days after surgery, patients received boosters of 10(6) U rIL-2 delivered into the tumor cavity through a skin flap or via an Ommaya reservoir. Approximately 1 to 2 weeks after this series of injections, these patients were treated with a second cycle of LAK cells and rIL-2 injected into the tumor cavity using the reservoir. Four patients received both adoptive immunotherapy cycles by intracavitary injection (Group 2). In this relatively small patient pool, neither age, sex, Karnofsky score, treatment history, nor anticonvulsant and steroid dosage appeared to influence a patient's ability to make LAK cells. The therapy, itself, was well-tolerated by all patients although they all displayed symptoms of aseptic meningitis and increased intracranial pressure, i.e., headache, fever, malaise on the days of LAK cell and/or rIL-2 infusion. The therapy did not appear to have a significant impact on patient survival (mean, 30 weeks) especially for those patients with a high postsurgical tumor burden. As the therapy is safe, the authors believe its efficacy can best be tested in patients with a newly diagnosed or recurrent glioblastoma which lies in an area where a near-total resection is possible.     

In situ tumor vaccination with interleukin-12-encapsulated biodegradable microspheres: induction of tumor regression and potent antitumor immunity

An alternative technology for the local and sustained delivery of cytokines to tumors for cancer immunotherapy was evaluated and shown here to induce tumor regression, suppression of metastasis, and development of systemic antitumor immunity. Treatment of tumor-bearing BALB/c mice with a single intratumoral injection of biodegradable polylactic acid microspheres loaded with recombinant interleukin-12 (IL-12) promoted complete regression of the primary tumor and prevented the metastatic spread to the lung. Mice that experienced tumor regression after being treated rejected a subsequent challenge with live tumor cells, which indicated the development of systemic antitumor immunity. In situ tumor vaccination, ie., injection of IL-12 microspheres into existing tumors, was superior to vaccination of mice with mixtures of tumor cells (live or irradiated) and IL-12 microspheres in inducing systemic antitumor immunity. The sustained release of IL-12 from the microspheres was superior to bolus injection of free IL-12, and intratumoral delivery of microspheres was more effective than other routes of administration. These studies establish the utility of biodegradable polymer microspheres as a clinically feasible alternative to systemic cytokine therapy and cytokine gene-modified cell vaccines for the treatment of neoplastic disease.     

Intratumoral PEG-interleukin-2 therapy in patients with locoregionally recurrent head and neck squamous-cell carcinoma

BACKGROUND: An enhanced efficacy of local as compared to systemic administrationof interleukin-2 (IL-2) has been demonstrated in several experimentaltumors. We previously reported that guinea pigs with palpabletumors and regional micrometastases could be cured by intratumoralinjections of polyethylene glycol-modified IL-2 (PEG-IL-2).In the present study this treatment schedule was applied ina clinical situation. PATIENTS AND METHODS: Nineteen patients with 11 local and 11 regional recurrencesof head and neck squamous cell carcinoma (HNSCC) were treatedwith intratumoral injections of 200,000 U of PEG-IL-2 3 timesweekly in courses of 4 weeks. RESULTS: Treatment was given on an out-patient basis, and was well tolerated.Temporary regional swelling and redness developed in 10 patients,and in 9 of them systemic eosinophilia was documented. Medianduration of treatment was 4 weeks (range 2–14 weeks).Seventeen patients were evaluable for response. One completeresponse (CR; 6%; duration 91 weeks), and 6 stable diseases(SDs; duration 8–57+ weeks) were recorded. The CR andthe 3 best SDs (23, 40, 57+ weeks) occurred in patients witha single regional tumor recurrence of relatively small size.During treatment, all 4 developed locoregional edema and redness,and high levels of circulating eosinophils. Median survivalwas 23 weeks for all patients, and 45+ weeks for the patientswith SD. CONCLUSION: Intratumoral injection of PEG-IL-2 in patients with HNSCC isfeasible. This treatment appears beneficial for highly selectedpatients. The objective response rate is insufficient to justifywide clinical application. head and neck squamous-cell carcinoma, immunotherapy, PEG-interleukin-2     

Combination therapy of colon carcinoma 26 in mice with recombinant human interleukin-2 and interferon-alpha A/D: occurrence of large granular cells in the tumor

The antitumor effects of recombinant human interleukin-2 (rIL-2), in combination with recombinant human interferon-alpha A/D hybrid (rIFN-alpha A/D) on colon carcinoma 26 (colon 26) in mice were examined histologically. Colon 26 was transplanted subcutaneously into female BALB/c mice on day 0. The mice bearing the tumor received intramuscular injections of rIL-2, rIFN-alpha A/D or the combination of rIL-2 and rIFN-alpha A/D for 2-10 consecutive days starting on day 7. Mice were killed on days 9, 13, 17 and 21. After day 13, growth of the tumor was significantly suppressed in the mice treated with rIL-2 or rIFN-alpha A/D alone and was stopped in the mice treated with rIL-2 in combination with rIFN-alpha A/D. Histologically, tumor necrosis developed in all treated groups, though the degree was the most severe in the group receiving combination treatment. Many large cells (about 15-30 microns in diameter) infiltrated into the tumor, and they had Thy-1 surface antigen and many periodic acid-Schiff-positive round granules in the cytoplasm. The incidence of these large granular cells was correlated well with the reduction in tumor weight. The ultrastructural features of the large granular cells were very similar to those of murine large granular lymphocyte-like cells maintained in vitro in an IL-2-containing medium. The present large granular cells appear to be a kind of activated lymphoid cells.     

ANTITUMOR EFFECTS OF POLYETHYLENE GLYCOLMODIFIED RECOMBINANT HUMAN INTERLEUKIN-2 ON MOUSE UTERINE CERVICAL CARCINOMA IN VIVO

Rqcombinanthumaninterleukin-2(rIL-2)isoneofthecytokines,whichplananimportantroleinantitllmorimmunotherapy.However,rIL-2haslimitedsolubility,andrIL-2israpidlyclearedfromcirculationofhumanwhenitisinjectedintohuman,resultinginshort-termplasmahalf-lifeandlimitedclinicalapplication.WehavemodifiedrIL-2bypolyethyleneglycol(PEG),whichincreaseditssolubilityandprolongeditsplasmahalf-life.Inthispaper,theantitumoreffectsofPEG-modifiedrecombinanthumaninterleukin-2(PEG-rIL-2)againstmouseuterinecervi…     

Combination therapy of an orthotopic renal cell carcinoma model using intratumoral vector-mediated costimulation and systemic interleukin-2.

PURPOSE: Interleukin (IL)-2 therapy is currently used for therapy of renal cell carcinoma (RCC). However, it is only effective in approximately 10% to 15% of patients, showing a need for additional therapies. We have previously described a replication-defective fowlpox vector encoding three costimulatory molecules (B7-1, ICAM-1, and LFA-3), designated rF-TRICOM. Here, we show that intratumoral administration of rF-TRICOM in an orthotopic RCC model effectively enhances tumor immunogenicity and reduces tumor burden in mice and the combination of rF-TRICOM and IL-2 is more effective than either therapy alone. EXPERIMENTAL DESIGN: RCC cells were implanted under the capsule of the kidney, and mice were given rF-TRICOM intratumorally 14 days later. We compared the effect of rF-TRICOM, rF-granulocyte macrophage colony-stimulating factor (GM-CSF), and two doses of IL-2 and combinations of the above on antitumor efficacy and survival. Host CD4(+) and CD8(+) T-cell responses were also evaluated. RESULTS: The results show that (a) systemic IL-2 therapy was moderately effective in the reduction of tumor burden in an orthotopic RCC model; (b) a single intratumoral injection of rF-TRICOM and rF-GM-CSF significantly reduced tumor burden; (c) the addition of systemic IL-2 to intratumoral rF-TRICOM/rF-GM-CSF administration resulted in further reduction of tumor burden, decrease in the incidence of metastasis, and extended survival in tumor-bearing mice above that seen with either treatment alone; and (d) CD8(+) T cells played a critical role in the antitumor effect seen with rF-TRICOM/rF-GM-CSF + IL-2 therapy. Finally, the addition of systemic recombinant IL-15 or intratumoral vector-delivered IL-15 to intratumoral rF-TRICOM/rF-GM-CSF administration resulted in substantially more tumor-free mice than either therapy alone. CONCLUSIONS: These studies show that intratumoral administration of rF-TRICOM admixed with rF-GM-CSF is effective at reducing tumor burden in mice and the addition of IL-2 further contributes to this effect. These studies thus form the rationale for combination immunotherapy clinical trials in patients with RCC.     

Lymphokine-activated killer cell plus recombinant interleukin-2 therapy of erythroleukemia in mice

The antileukemic effects of lymphokine-activated killer (LAK) cells plus recombinant interleukin-2 (rIL-2) therapy were assessed in mice with Friend virus (FV)-induced erythroleukemia. LAK cells were generated by incubating normal spleen cells for 72 hr in the presence of rIL-2 (1000 units/ml). At the time of injection, the LAK cells were cytotoxic in vitro against FV-infected fibroblasts and NK-sensitive and -resistant tumor targets but not normal controls. To determine in vivo activity, fully leukemic mice (spleen weight greater than 0.75 g) were injected with either PBS or LAK cells (10(8) cells/mouse IV at 14 and 17 days post virus) and rIL-2 (10,000 units/mouse IP every 8 hr on days 14 through 18 post virus). More than 70% of the progressively leukemic mice experienced permanent leukemia regressions (disease-free for greater than 100 days) following LAK cell plus rIL-2 therapy. Regressions were characterized by return of spleen and liver weights to normal and elimination of virus-infected erythroid (CFU-E) and macrophage (CFU-C) progenitor cells from spleen and marrow. Leukemic animals treated with either LAK cells alone or IL-2 alone experienced only transient leukemia regressions. These results demonstrate that LAK cell plus rIL-2 treatment can induce permanent regressions in progressively leukemic mice and provide a responsive and manipulable model system to elucidate the mechanisms involved in this form of immunotherapy.     

Splenic versus hepatic artery infusion of interleukin-2 in patients with liver metastases

In an attempt to improve the therapeutic index of recombinant interleukin-2 (rIL-2) by generating or activating lymphokine-activated killer (LAK) cells and tumor-infiltrating lymphocytes (TIL) regionally and/or in situ, we randomly assigned 28 patients with liver metastases to receive rIL-2 by continuous infusion for 5 days via either the splenic artery or the hepatic artery. Clinically significant and lasting tumor regression was observed only in two of 28 patients (7%), one in each of the two treatment arms. The maximum-tolerated daily dosage of rIL-2 was 3 x 10(6) U/m2; beyond this dosage, toxicity was excessive. Peripheral LAK cell activity measured in vitro and clinical tumor regression did not correlate. This observation, coupled with the equal distribution of regressions between the two treatment arms, raises the possibility that tumor regression, rare though it may be in response to rIL-2 administration, is largely mediated by TIL activation and not by LAK cell generation.     

Antitumor effector mechanism of interleukin-1 beta at a distant site in the double grafted tumor system.

Recombinant human interleukin-1 beta (IL-1 beta) inhibited the growth of not only the right, but also the left non-treated tumor in a double grafted tumor system. Since the antitumor activity of IL-1 beta against the right and left tumors was not seen in nude mice, lymphocytes have a key role in the antitumor effect of intratumoral administration of IL-1 beta. TIL (tumor-infiltrating leukocytes) obtained from left and right side tumors treated with IL-1 beta were examined by Winn assay for their antitumor activity against Meth-A sarcoma in BALB/c mice. TIL from the right side clearly inhibited the growth of admixed Meth-A cells, but control TIL did not. Spleen cells and right and left regional lymph node cells prepared from IL-1-treated mice were examined for Lyt-1, Lyt-2 and L3T4 phenotypes. The number of Lyt-1-positive lymphocytes increased in the spleen and in the right regional lymph nodes after intratumoral administration of IL-1. Isolated tumor cells obtained from the right tumor treated with IL-1 beta and the left side tumor on day 6 were cultured in RPMI 1640 with 10% fetal calf serum for 24 h. The culture supernatants were harvested and tested for the presence of chemotactic activity for neutrophils or macrophages. Significant neutrophil chemotactic factor and macrophage chemotactic factor activities were detected in the culture media from IL-1-treated tumor tissues cultured for 24 h. Neither significant neutrophil nor macrophage chemotactic activity was detected in the media from untreated tumor tissues. These results suggest that intratumoral administration of IL-1 first induces neutrophils and macrophages in the right tumor, then Lyt-1-positive cells in the right regional lymph nodes and in the spleen, and subsequently induces macrophages in the left, non-treated tumor.     

Augmented antitumor effect of recombinant human interleukin-1 alpha by indomethacin

In murine syngeneic tumor models, the antitumor effect of recombinant human interleukin-1 alpha (rHu IL-1 alpha) was significantly augmented by oral coadministration of indomethacin (IND). The augmentation was more or less observed by various routes of rHu IL-1 alpha (i.m., i.v., and intratumoral routes), against various tumors (Meth A sarcoma, colon 26 adenocarcinoma, B16 melanoma, and Lewis lung carcinoma) and irrespective of administration timings (in early and late stages of tumor growth). This results suggests that prostaglandin E2 produced by host cells in response to rHu IL-1 alpha and/or by tumor mass might interfere with the antitumor activity of rHu IL-1 alpha and also that cyclooxygenase inhibitors such as IND might counteract such interference. In the combination of rHu IL-1 alpha with IND, its efficacious doses (5-50 micrograms/kg) against murine tumors were at least 300-3000 times lower than its median lethal dose (more than 15 mg/kg). In addition, IND partially prevented the loss of body weight attributed to rHu IL-1 alpha injections at relatively high doses. Combined use of rHu IL-1 alpha with IND seems to be desirable from both therapeutic and toxicological viewpoints.     

Treatment of hepatocellular carcinoma utilizing lymphokine-activated killer cells and interleukin-2

This paper is a report on adoptive immunotherapy involving consecutive injections of recombinant interleukin-2 and lymphokine-activated killer (LAK) cells in the treatment of hepatocellular carcinoma. Peripheral blood lymphocytes, obtained by leukopheresis, acted as the activated killer cells with a co culture of recombinant interleukin-2 in the culture system. After 4 days, the activated killer cells were returned into the patients' bodies intra-arterially and intravenously. No complete remissions or partial remissions have resulted, although five of the seven patients showed a significant decrease in their serum -fetoprotein levels after treatment. In addition, one case showed a patent portal truncus while another indicated the appearance of central necrosis on the computerized tomograph scan. Although the period of observation was short, there were no recurrences after the combination therapy of tumor resection and LAK adoptive immunotherapy. It might be difficult to treat hepatocellular carcinoma with adoptive immunotherapy alone, but there is some possibility of conducting therapy for hepatocellular carcinoma after removing the majority of the tumor cells by surgical resection and transcatheter arterial embolization therapy. This conclusion indicates, at least theoretically, that adoptive immunotherapy will be suitable in the treatment of hepatocellular carcinoma as one of the combination therapies with the two major forms of treatment mentioned above.     

Local adoptive immunotherapy of advanced head and neck tumors with LAK cells and interleukin-2

Since October 1987 a pilot phase I-II study on the effect of loco-regional injections of recombinant interleukin 2 (rIL-2) in association with LAK cells has been performed in advanced, recurrent head and neck cancer patients. Fourteen patients were treated with autologous LAKs and rIL-2 (Glaxo) given peritumorally and in the mastoid region (rIL-2 only in the latter site). LAKs (2-70 x 10(7)) + rIL-2 were injected on the first day of therapy, followed by 9 daily injections of rIL-2 only. The total daily dose of rIL-2 was escalated from 2,400 to 1.8 x 10(6) IU. Clinical evaluation was performed 30 days from the onset of therapy; 3 partial (95%, 66% and 50% reduction) and 3 minor responses were seen in the evaluated patients. All the other patients with a progressive disease after the first cycle were shifted to palliative chemotherapy. The partial responses were found in patients with a tumor burden less than 20 cm2. Cervical node metastasis did not respond to treatment. No relevant side effects occurred. These results indicate that loco-regional immunotherapy with rIL-2 and LAK cells can produce clinical responses in advanced head and neck cancer patients.