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A Newcastle disease virus (NDV) oncolysate has been established as a unique and effective immune-stimulatory root for tumor treatment. Thus, the aim of the current study was to investigate the effects of intratumoral administration of NDV oncolysate on immune response and tumor regression of C57BL/6 mouse model of human papillomavirus (HPV) related transplanted with TC-1 syngeneic cancer cells. To further investigate the mechanism underlying the antitumor response, cytolytic and lymphocyte proliferation responses in splenocytes were measured using lactate dehydrogenase (LDH) release and MTT assays, respectively. In this regard, levels of IL-10, IFN-γ, and IL-4 were measured using ELISA after re-stimulation. The immune responses efficacy was evaluated by in vivo tumor regression assay. The results showed that immunization with the different titers of NDV lysate significantly reduced tumor volume in comparison with a combination of virus lysate and tumor cell lysate. Also, virus lysate could significantly enhance cytotoxic T lymphocyte production and lymphocyte proliferation rates versus tumor cell lysate. Also, our major findings are that the peritumorally injection of NDV oncolysate effectively induces antitumor immune responses through increased levels of IL-4, IFN-γ, and reduction of IL-10. These results indicate that this treatment is a specific, active immune mechanism stimulator, and may prove to be a useful therapeutic for a treatment against cervical cancers and merits further investigation.

T-VEC, a HSV-1 derived oncolytic virus, is approved for the treatment of advanced melanoma. The mechanisms that underly the systemic anti-tumor effect that is seen following intratumoral injection have not yet been studied but are likely to be mediated by myeloid dendritic cells (myDC) that initiate an adaptive immune response. In this study we could demonstrate that T-VEC is non-toxic for human myDC. T-VEC and a T-VEC oncolysate of melanoma cell lines were able to mature human myDC. myDC were able to take up lysed melanoma cells and cross-present melanoma-derived tumor antigens to antigen-specific T cells. Our results support the possible role of myDC as mediators of an adaptive anti-tumor effect and intratumoral co-administration of T-VEC plus autologous myDC could be a complementary treatment option. A clinical trial that investigates this hypothesis is currently ongoing. ispartof: FRONTIERS IN IMMUNOLOGY vol:12 ispartof: location:Switzerland status: published

Oncolytic adenoviruses are emerging agents for treatment of cancer by tumor-restricted virus infection and cell lysis. Clinical trials have shown that oncolytic adenoviruses are well tolerated in patients but also that their antitumor activity needs improvement. A promising strategy toward this end is to trigger systemic and prolonged antitumor immunity by adenoviral oncolysis. Antitumor immune activation depends in large part on antigen presentation and T cell activation by dendritic cells (DCs). Thus, it is likely that the interaction of lysed tumor cells with DCs is a key determinant of such "oncolytic vaccination." Our study reveals that human DCs effectively phagocytose melanoma cells at late stages of oncolytic adenovirus infection, when the cells die showing preferentially features of necrotic cell death. Maturation, migration toward CCL19 and T cell stimulatory capacity of DCs, crucial steps for immune induction, were, however, not induced by phagocytosis of oncolysate, but could be triggered by a cytokine maturation cocktail. Therefore, oncolytic adenoviruses and adenoviral oncolysate did not block DC maturation, which is in contrast to reports for other oncolytic viruses. These results represent a rationale for inserting immunostimulatory genes into oncolytic adenovirus genomes to assure critical DC maturation. Indeed, we report here that adenoviral transduction of melanoma cells with CD40L during oncolysis triggers the maturation of human DCs with T cell stimulatory capacity similar to DCs matured by cytokines. We conclude that triggering and shaping DC-induced antitumor immunity by oncolytic adenoviruses "armed" with immunostimulatory genes holds promise for improving the therapeutic outcome of viral oncolysis in patients.

The natural adjuvant properties of bacterial ghosts (BGs) lie within the presence of intact pathogen-associated molecular patterns on their surface. BGs can improve the direct delivery, natural processing and presentation of target antigens within dendritic cells (DCs). Moreover, sensitization of human DCs by cancer cell lysate (oncolysate)-loaded BGs in the presence of IFN-α and GM-CSF enhanced DC maturation as indicated by an increased expression of maturation markers and co-stimulatory molecules, higher production of IL-12p70 and stimulation of significantly increased proliferation of both autologous CD4+ and CD8+ T cells compared to DCs matured in the presence of purified lipopolysaccharide. The induced T cells efficiently recognized oncolysate-derived tumor-associated antigens expressed by cancer cells used for the production of oncolysate. Our optimized one-step simultaneous antigen delivery and DC maturation-inducing method emerges as a promising tool for the development and implementation of next-generation cellular cancer immunotherapies.

The development of effective adjuvant therapies for the treatment of high-risk melanoma patients is critical for the prevention of metastatic disease and improvement of patient survival. Active specific immunotherapy has been tested as an adjuvant treatment in numerous clinical trials with overall limited, but occasionally promising, success rates. Newcastle disease virus (NDV) oncolysate has been utilized as an adjunctive immunotherapeutic agent in the postsurgical management of these patients. A phase II study initiated in 1975 using adjuvant vaccine therapy composed of allogeneic and autologous human melanoma cells infected with live NDV (NDV oncolysate) in patients with AJCC stage III melanoma following therapeutic lymph node dissection has shown >60% survival rate at 10 years with no adverse effects. Continued long-term analysis of trials with promising early results as well as assessment of immunologic responses generated in these patients may result in improved therapeutic decisions for clinical trials in the future. We analyzed the 15-year survival of patients treated postsurgically with NDV oncolysate in the phase II study described above. In an attempt to understand the immunological effects of this treatment, we have also carried out a comprehensive analysis of the peripheral blood T cell repertoire in these patients. The overall 15-year survival of this group of patients is 55%. Previous studies have suggested that improved outcome in patients undergoing immunotherapy is correlated with increased numbers of CD8+CD57+ cells. In surviving patients, we observed a striking oligoclonality in the CD8+ T cell population in peripheral blood, which reflects clonal expansions in the CD8+CD57+ subset. The data suggest that adjuvant vaccination with NDV oncolysates is associated with prolonged survival of patients with lymph node-positive malignant melanoma and that CD8+ T cells may be an important component of therapeutic efficacy.

Dendritic cell-based active immunotherapies of cancer patients are aimed to provoke the proliferation and differentiation of tumor-specific CD4(+) and CD8(+) T-lymphocytes towards protective effector cells. Isolation and in vitro differentiation of circulating blood monocytes has been established a reasonable platform for adoptively transferred DC-based immunotherapies. In the present study the safety and tolerability of vaccination by autologous tumor cell lysates (oncolysate)- or carcinoembriogenic antigen (CEA)-loaded DCs in patients with colorectal cancer was investigated in a phase I-II trial. The study included 12 patients with histologically confirmed colorectal cancer (Dukes B2-C stages). Six of the patients received oncolysate-pulsed, whereas the other six received recombinant CEA-loaded autologous DCs. The potential of the tumor antigen-loaded DCs to provoke the patient's immune system was studied both in vivo and in vitro. The clinical outcome of the therapy evaluated after 7 years revealed that none of the six patients treated with oncolysate-loaded DCs showed relapse of colorectal cancer, whereas three out of the six patients treated with CEA-loaded DCs died because of tumor relapse. Immunization with both the oncolysate- and the CEA-loaded autologous DCs induced measurable immune responses, which could be detected in vivo by cutaneous reactions and in vitro by lymphocyte proliferation assay. Our results show that vaccination by autologous DCs loaded with autologous oncolysates containing various tumor antigens represents a well tolerated therapeutic modality in patients with colorectal cancer without any detectable adverse effects. Demonstration of the efficacy of such therapy needs further studies with increased number of patients.

Vaccinia melanoma oncolysate (VMO) prepared by infecting B16F10 melanoma cells with recombinant vaccinia virus encoding murine GM-CSF gene was tested for its therapeutic effect on the preestablished melanoma. C57BL/6 mice were inoculated s.c. with 1 × l0 5 B16F10 melanoma cells and received s.c. administration with VMO prepared with GM-CSF gene-encoded vaccinia virus(GM-CSFVMO), VMO prepared with thymidine kinase gene-deficient vaccinia virus(TKVMO), B16F10 melanoma oncolysate(BMO), or PBS 3 days after tumor inoculation. The same treatment was bolstered one week later. The results demonstrated that GM-CSFVMO treatment significantly inhibited the growth of subcutaneous tumor and prolonged the survival period of tumor-bearing mice. Further study elucidated that cytotoxicity of PBL and splenocytes towards B16F10 increased obviously after treatment with GM-CSFVMO, but NK activity remained unchanged. These results suggest that the tumor oncolysate vaccine prepared with GM-CSF gene-encoded vaceinia virus might exert potent therapeutic effect on the preestablished tumor through the efficient induction of specific antitumor immune response of the host.

Background. Although a wealth of information is available on adjuvant immunotherapy for melanoma, little is known about adjuvant immunotherapy for head and neck melanoma. Interestingly, a few immunotherapy clinical trials report the observation of clinical responses in a subset of patients with head and neck melanoma. Method. An up-to-date literature search was performed to identify the current information on adjuvant immunotherapy for patients with melanoma, including head and neck melanoma. Moreover, a retrospective analysis of a subset of primary head and neck melanoma was performed using data from a phase III, randomized, double-blind, multi-institutinal, vaccinia melanoma oncolysate adjuvant immunotherapy trial that was performed in our laboratory for patients with stage III (AJCC) melanoma. Results. In a passive immunotherapy trial with an antibody to melanoma ganglioside antigen GM2, a complete regression was observed in one patient with lesions of the right cheek. In three active specific immunotherapy trials, including our phase III trial, a subset of patients with head and neck primary melanoma showed a longer disease-free and overall survival with immunotherapy. Moreover, these clinical responses were correlated to the induction of immune response, delayed-type hypersensitivity response and melanoma-specific antibody response. Conclusions. The above results therefore suggest that patients with head and neck melanoma clinically respond to immunotherapy. However, these results need to be confirmed in a prospectively randomized trial for patients with head and neck melanoma.

A 67-year-old man with metastatic melanoma and chronic lymphocytic leukemia was inadvertently given a vaccinia melanoma oncolysate vaccination. He developed progressive vaccinia at the site of inoculation. The lesion started to heal only when he was treated with ribavirin. Vaccinia immune globulin was administered and appeared to help control the initial lesion and limit the development of satellite lesions.

Development of a melanoma-specific vaccine is of clinical necessity. Therefore, a phase III, randomized, double-blind trial was performed (June 1988–June 1991) to assess the clinical effectiveness of our vaccinia melanoma oncolysate (VMO) vaccine in stage III melanoma patients. Patient data were collected from 11 institutions, as well as from the Social Security Death Index and were analyzed from April through August 2008 for disease-free interval (DFI) and overall survival (OS). The median OS for patients who were administered the VMO vaccine was 7.71 years, compared to 7.95 years for patients administered the vaccinia virus vaccine (V) (p=0.70). The median DFI for the VMO group was six years, while the median DFI for the V group has not yet been reached. This analysis demonstrated a statistically significant difference in OS in females in both groups (VMO, 79%; V, 92%), as compared to males (VMO, 57%; V, 68%) (p=0.0473). This follow-up analysis demonstrated that females had a survival advantage over males, thus warranting further investigation. This significant observation may facilitate the recruitment of patients for future clinical trials, as well as determine which patients are more likely to benefit from receiving the VMO vaccine.

Background. In a Phase II trial, surgical adjuvant active specific immunotherapy using a live vaccinia virus-augmented allogeneic polyvalent melanoma cell lysate, vaccinia melanoma oncolysate (VMO), produced a significant disease free interval (DFI) in patients with International Union Against Cancer Stage II melanoma with positive lymph nodes. Therefore, a Phase III randomized prospective, double-blind, multiinstitutional, surgical adjuvant VMO trial was performed to determine the efficacy of VMO to increase the DFI and the overall survival in this group of patients with Stage II disease. Methods. Two hundred and fifty patients with Stage II melanoma were divided into two postsurgical groups. One group received VMO (total protein equals 2 mg/ml) and the other received the placebo of live vaccinia vaccine virus (V) (105.4 TCID50/ml), an adjuvant component of the VMO. Patients initially received these biologies once a week for 13 weeks and then once every 2 weeks for an additional 39 weeks or until recurrence. All surviving patients have been followed for at least 30 months. Results. Statistical analysis of survival data (n = 217) for this first interim analysis shows that there is no statistically significant (P = 0.99) increase in DFI of patients treated with VMO (n = 104) when compared with V (n = 113). The median DFI is 38.0 months for patients treated with VMO and 37.0 months for patients treated with V. At 2- and 4-year intervals, 70 and 38%, respectively, of patients treated with VMO vs. 66 and 36%, respectively, of patients treated with V were free of melanoma. The median overall survival is not available because the pa-tients treated with VMO have not yet reached the 50% mark and the median overall survival is 45.0 months for patients treated with V. At 2- and 4-year intervals, 70 and 38%, respectively, of VMO-treated patients survived when compared with 66 and 36%, respectively, of pa-tients treated with V. Although the overall survival of pa-tients treated with VMO is not statistically significant (P = 0.88) at this point, there is an increasing trend in the overall survival of patients treated with VMO; a 10% increase at the 4-year time point. Moreover, in the subset analysis, VMO-treated male patients (n = 63) showed a 17% improvement in survival at 4-year time point when compared with male patients treated with V (n = 67) (P = 0.19) at the same time point and male patients (n = 20) between the ages of 44 and 57 having 1-5 positive lymph nodes showed a 37% difference in overall survival at the 4-year time point when compared with those patients treated with V (n = 18) (P = 0.13) at the same time point. Conclusion. In this first interim analysis, active specific immunotherapy with VMO vs. V showed no difference in the disease free interval or overall survival. Subset analyses likewise showed no significant differences in outcome but the data suggest a potential difference in immunoreactivity between male and female patients with melanoma that awaits further follow up and may merit further investigation.

The role of cytokines as primary or adjuvant antineoplastic agents has been well established. Interleukin-2 (IL-2) and the interferons have, particularly, proven to be effective antitumor agents when given alone, and seem to act synergistically on the eradication of metastases from immunogenic tumors. Active specific immunotherapy, in the form of viral oncolysates, has also shown effectiveness in cancer therapy. Bearing this in mind, we decided to combine these agents in an adjuvant triple regimen and compare their effectiveness to other treatments in terms of tumor burden and survival in a murine colon cancer hepatic metastases model. BALB/c mice were injected with CC-36, a weakly immunogenic murine colon adenocarcinoma, intrasplenically, to produce artificial liver metastases. The animals were divided into one control group and seven treatment groups receiving either vaccinia colon oncolysate (VCO), IL-2, interferon-alpha (IFN alpha) alone, or combinations of these agents. Half the animals were followed for survival and the other half were sacrificed at the end of the experiment for quantification of tumor burden. The blood of the sacrificed animals was utilized in a series of immunological tests in order to demonstrate the cytolytic potential of the peripheral blood lymphocytes (PBL) in each treatment group, as well as to characterize phenotypically the cells acting as effectors. The triple-adjuvant regimen group was by far the most effective treatment group, demonstrating 100% survival and a significant reduction in tumor burden when compared to other groups. Furthermore, the PBL from the animals in this group showed 69.4% lysis of the CC-36 target cells in vitro. These effector lymphocytes were characterized as ASMG1-/Lyt2.2+ cytolytic lymphocytes. We conclude that these lymphocytes were stimulated by the administration of VCO and further augmented by the immunomodulation of the cytokines given in the triple regimen, and that such a regimen might prove beneficial in the treatment of established hepatic metastases from weakly immunogenic tumors.

Dendritic cells (DCs) possess the unique abilities to initiate a primary immune response and to present antigens to naive T lymphocytes. Recently, there has been a rapidly growing interest in the use of DCs in active specific immunotherapy (ASI) for the treatment of patients with cancer. In the present study, we determined the ability of DCs to express Melanoma-Associated Antigens (MAAs) from a polyvalent Melanoma Vaccine (DC-MelVac; Patent# 11221/5) developed in our facility. The vaccine consists of a recombinant IL-2 gene-encoded vaccinia melanoma oncolysate (rIL-2VMO) derived from an established human melanoma cell line. Our results show that r-IL2VMO-pulsed DCs express MAAs presented by the Mel-2 melanoma cell line oncolysate used in this study. We believe that these promising results will prove useful as an active specific immunotherapeutic agent for patients with Stage III melanoma.

Background This study was conducted to test the efficacy of a new cancer vaccine, composed of dendritic cells (DCs) pulsed with an interleukin-2 gene-encoded vaccinia virus tumor oncolysate (DC-IL-2VCO) in a CC-36 murine colon adenocarcinoma model. Materials and methods CC-36 tumor cells were injected subcutaneously into the left flank of four- to six-week old male BALB/c mice. The mice were divided into three groups, each of which received one of the following treatments: (1) DCs pulsed with the IL-2 gene-encoded vaccinia oncolysate (DC-IL-2VCO), (2) DCs pulsed with the tumor oncolysate alone (DC-CO), or (3) no treatment (control). Tumor incidence was measured, and survival rates were compared using a paired Student’s t-test. Cytolytic T cell activity was measured in peripheral blood lymphocytes (PBL) and splenic lymphocytes using a 51Cr-release assay. Lastly, mice were depleted of either CD4+ or CD8+ lymphocytes prior to receiving the vaccine to test the mechanism of tumor immunity in these mice. Results Mice treated with DC-IL-2VCO demonstrated decreased tumor burden, increased survival, and greater cytolytic activity compared with control mice and mice receiving DC-CO. In addition, mice depleted of CD8+ T cells prior to immunization with IL-2VV + DC-IL-2VCO had a significant increase in the incidence of tumor, similar to the untreated control mice. Conclusions DCs pulsed with an IL-2 gene-encoded vaccinia virus tumor oncolysate (DC-IL-2VCO) produced safe and effective immune responses in a murine CC-36 colon adenocarcinoma model. This vaccine (DC-MelVac; Patent no. 11221/5) has the potential to treat humans with cancer, and has received FDA approval for use in Phase I clinical trials.

A phase III, randomized, double-blind, multi-institutional vaccinia melanoma oncolysate (VMO) trial was performed for patients with stage III (AJCC) melanoma. When compared with the control vaccinia virus (V) therapy, VMO therapy did not show clinical efficacy in the final analysis of data from this trial. However, the data did allude to significant therapeutic efficacy with VMO therapy if it had been compared with an observation arm. Therefore, a comparative overview statistical analysis was performed to identify the therapeutic efficacy of VMO. This review compares VMO results with data from the treatment and observation arms of other prominent randomized anti-melanoma biologic trials (i.e., ECOG EST 1684; SWOG, IFN-gamma (J. Natl. Cancer Inst. 87 (1995) 1710); WHO IFN-alfa-2a (ASCO 14 (1995) 410); Mayo IFN-alfa-2a (J. Clin. Oncol. 13 (1995) 2776); French IFN-alfa-2a (ASCO 15 (1996) 437). The analysis was carried out comparing the disease-free interval (DFI) and overall survival (OS). The analysis shows that the VMO results are fairly comparable to the results of the treatment arms from the ECOG and Mayo trials at the 5-year mark; percent DFI 0.37, 0.37, and 0.4, percent OS 0.48, 0.46, 0.47, respectively. In some cases, VMO DFI is superior to the observation arms from other studies; ECOG, Mayo, and WHO; 0.37 versus 0.26, 0.3, 0.27 (4 years), respectively. These comparative results suggest that the vaccinia arm is not a true observation arm in the VMO trial, and the VMO could have shown an enhanced efficacy had the trial included a no-treatment observation control arm.

OBJECTIVE: The efficacy of vaccinia melanoma oncolysate (VMO) vaccine to increase overall survival and disease-free survival of patients with surgically resected International Union Against Cancer (UICC) stage II melanoma was studied in a phase III, randomized, multi-institutional trial. SUMMARY BACKGROUND DATA: Phase I and II trials with VMO showed minimal toxicity and clinical efficacy in patients with melanoma. In a recently completed phase III VMO trial, the first interim analysis performed in April 1994 showed an increasing trend in the survival of patients treated with VMO. The second interim analysis was performed in April 1995. METHODS: Patients with surgically resected stage II (UICC) melanoma were treated with VMO (N = 104) or placebo vaccinia vaccine virus (V) (N = 113) once a week for 13 weeks and then once every 2 weeks for a total of 12 months. Patients' clinical data were collected as of May 1995 and analyzed for survival. RESULTS: In this second interim analysis, the mean follow-up time is 42.28 months. No survival difference was observed between VMO and V treatments. However, in a retrospective subset analysis, a subset of males between the ages of 44 and 57 years and having one to five positive nodes (at 2-, 3-, and 5-year intervals, 13.6%, 15.9%, and 20.3% difference insurvival in favor of VMO [N = 20] when compared to V [N = 18] [p = 0.037]) and another subset of patients with clinical stage I (at 3- and 5-year intervals, 30% and 7% difference in survival in favor of VMO [N = 20] when compared to V [N = 23], [p = 0.05]) showed significant survival advantage with VMO. CONCLUSIONS: Although VMO vaccine therapy in surgical adjuvant setting did not produce a significant survival benefit to all patients with melanoma, patients from the above two subsets had significant survival benefit.

A phase III, randomized, double-blind, multi-institutional trial was performed evaluating active specific immunotherapy using vaccinia melanoma oncolysate (VMO) in the surgical adjuvant setting in patients with stage II melanoma (UICC staging). The first interim analysis showed no significant difference in disease-free and overall survival. The data were further analyzed to identify subsets of patients with improved outcome when treated with VMO.Patients received either VMO or placebo of live vaccinia vaccine virus (V), once a week for 13 weeks and then once every 2 weeks for an additional 39 weeks or until recurrence. Having stratified patients according to sex, age, number of positive nodes, tumor thickness, and clinical stage, data were analyzed for disease-free survival and overall survival.Male patients showed a 17% difference in overall survival at 4 years when treated with VMO (p = 0.19). A subset of male patients57 years of age with one to five positive nodes showed a 30% difference at 4 years with VMO (p = 0.06). Patients with clinical stage I but pathological stage II disease (both male and female), who had undergone prophylactic node dissection, showed a 23% difference in survival at 3 years with VMO (p = 0.11).This subset analysis shows encouraging survival benefit in certain subsets of patients and an increasing trend in overall survival. Further follow-up of this phase III trial from a second interim analysis will be forthcoming.

Vaccinia melanoma oncolysate (VMO) prepared with recombinant vaccinia virus encoding the gene of murine granulocyte/macrophage-colony-stimulating factor (GM-CSF) was tested for its therapeutic effect on melanoma pulmonary metastasis. The murine pulmonary metastasis model was established by injecting 2 x 10(5) B16F10 melanoma cells into the tail vein of a C57BL/6 mouse. Intraperitoneal injection of VMO was performed in tumor-bearing mice 3 and 10 days after B16F10 cell inoculation. The results showed that treatment with VMO prepared with GM-CSF-gene-encoded vaccinia virus (GM-CSFVMO) significantly decreased the number of murine pulmonary metastases and prolonged the survival of the tumor-bearing mice. Lymphocytes isolated from fresh blood and spleen of GM-CSFVMO-treated mice showed higher cytolytic activity against B16F10 melanoma cells when compared with lymphocytes from the mice of other treatment groups. Natural killer activity remained unchanged in the GM-CSFVMO-treated group. Cytotoxic activities of peritoneal macrophages were found to be greatly elevated in mice treated with GM-CSFVMO. Further study illustrated that the increased tumor necrosis factor and nitric oxide release from macrophages may contribute to their cytotoxic effects. These results suggest that the tumor oncolysate vaccine prepared with GM-CSF-gene-encoded vaccinia virus has a potent therapeutic effect on tumor metastasis through the efficient induction of antitumor immunity of the host, mainly through the cytotoxic effects of cytotoxic T lymphocytes and macrophages.

This paper deals with the design of tumor vaccines for either prophylactic application, such as viral vaccines, or for therapeutic application in cancer patients. It discusses important aspects in the design of vaccines which come from experience in the fields of infectious diseases and autoimmunity. As examples of tumor vaccines which are presently being tested, virus-infected tumor cell vaccines and gene-transfected tumor cell vaccines are further discussed. Such live cell vaccines are compared with oncolysate vaccines or vaccines prepared from purified tumor antigens and adjuvants. Future perspectives of such approaches for biotherapy of cancer are also discussed.

Vaccinia CC-36 murine colon oncolysate (VCO) prepared with interleukin-2-gene encoded recombinant vaccinia virus (IL-2VCO) was used in the treatment of a syngeneic murine colon adenocarcinoma (CC-36) hepatic metastasis to test the beneficial effect of the interleukin-2-gene encoded vaccinia virus over a control recombinant vaccinia virus in producing a vaccinia oncolysate tumor cell vaccine. Results suggest that the IL-2VCO treatment significantly reduced the hepatic tumor burden in comparison with the controls that received either IL-2-gene-encoded recombinant vaccinia virus or a plain recombinant vaccinia virus or vaccinia oncolysate prepared with the plain recombinant virus. The survival of mice treated with IL-2VCO was also improved in comparison with mice treated with other preparations. The induction of a cytolytic T lymphocyte response was examined to elucidate the mechanism of the induction of antitumor responses in IL-2VCO-treated mice. Fresh peripheral blood lymphocytes (PBL) isolated from IL-2VCO-treated mice showed a higher cytolytic activity against CC-36 tumor cell target when compared to PBL from the mice of other treatment groups, suggesting that the IL-2VCO induced an antitumor cytolytic T lymphocyte response. These results suggest that a vaccinia oncolysate, prepared with recombinant vaccinia virus encoding an immunomodulating cytokine gene will enhance antitumor responses in the host.

e19031 Background: We present a 10-year analysis of the first randomized, prospective, double-blind, multi- institutional melanoma vaccine trial with patients treated with either vaccinia melanoma ...

We reported earlier that oncolysate retained in the excision wound of a local tumor inhibits growth of remote tumor in the rat. We further studied this effect on pulmonary metastasis. C57BL/6 mice were given B16 melanoma F10 cells subcutaneously into the gluteal area (Day 0) and then intravenously on Day 10. On Day 14, mice were divided into four groups. Group 1 received a sham operation and no further treatment. Tumors were excised in the remaining mice. Group 2 received tumor excision alone. Groups 3 and 4 received injections of freeze-lysed tumor cells (TC) and lysate modified (PTC) with a hapten, L-phenylalanine mustard (PhM), respectively, into excision wounds. On Day 24, metastases were assessed by determining metastatic burden. Average diameters of excised tumors in repeated experiments ranged from 8.7 to 10.9 mm. In repeat experiments, pulmonary metastatic burden increased by as much as 52 to 181% in the tumor excised group (Group 2) in comparison with those receiving sham surgery (Group 1). However, metastatic burden was always reduced in Group 3. An even greater reduction was seen in Group 4. To study the possible involvement of macrophages, the production of prostaglandin-E2 (PGE2) and cytotoxicity of macrophages in these animals were examined. It was found that tumor excision enhanced PGE2 production by macrophages and suppressed their cytotoxicity, while TC inoculation prevented both of these changes. An even greater prevention was observed with PTC inoculation. These results indicate an association among macrophage cytotoxicity, PGE2 production of macrophages, and metastasis. In order to clarify the mechanism for these reactions, we did experiments using adherent splenic macrophages from the four groups of animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Newcastle disease virus oncolysate was examined as an adjunctive immunotherapeutic agent in the postsurgical management of 83 cases of Stage II malignant melanoma. At this time, all the patients have been under observation for at least 10 years, and over 60% are alive and free of recurrent disease. Older studies in the United States report postsurgical survival figures for Stage II cases of 5-15%. More contemporary studies indicate a 33% survival at 10 years. The unusual disease-free survival periods in the present study, including exceptional survivals in 21 patients with head and neck disease and six cases with cerebral metastases, suggest a unique role for the administration of Newcastle disease virus oncolysate in the management of Stage II malignant melanoma patients.

Vaccinia melanoma oncolysate is an investigative agent for active specific adjuvant immunotherapy. Viral oncolysate work in animals has led to application of this treatment in humans. Success of initial trials in treatment of melanoma has led to a phase III randomized, prospective, double-blind, multi-institutional trial, which is currently under way.

SELECTED CASES CASE 1. —A 26-year-old woman was referred to the Surgery Branch, National Cancer Institute, Bethesda, Md, with metastatic melanoma. A year earlier the patient had noted an enlarging mole on her right upper extremity; the results of the biopsy revealed a melanoma. She underwent a wide local excision and right axillary lymph node dissection. Of 30 lymph nodes, two contained melanoma. Despite experimental treatment with vaccinia tumor oncolysate, her disease progressed. On presentation to the National Institutes of Health in June 1989, she had about 30 subcutaneous deposits of melanoma, multiple lung metastases, and oral lesions on her tonsils and soft palate. On June 21,1989, she underwent resection of six separate subcutaneous lesions ranging in diameter from 2 to 5 cm to harvest tumor-infiltrating lymphocytes (TIL) (T cells that infiltrate into animal and human tumors and can be grown in culture with interleukin 2 [IL-2]). 1 Eight days

A live vaccinia vaccine virus-augmented and lysed murine tumor cell vaccine (vaccinia oncolysate) is used as a specific active immune mechanism stimulator in a syngeneic SV40-transformed BALB/c male mouse peritoneal macrophage tumor system. BALB/c mice pretreated with subcutaneous injections of vaccinia oncolysates prior to challenge with tumor cells failed to develop tumors at the injection sites. Cross-immunization and immunotherapy experiments were also performed. Because of the encouraging results in this murine tumor system, preliminary trials were instituted to evaluate vaccinia oncolysates as an immunotherapeutic agent in human cancer.

A vaccinia virus-lysed autochthonous tumor cell vaccine (vaccinia oncolysate) is introduced as a new specific, active immunotherapeutic agent against human cancer. Mouse experiments showed the vaccine to be a safe and potent immune mechanism stimulator. Human experimentation was undertaken in the knowledge of relative safety of the components of the vaccine, i.e. vaccinia vaccine and lysed, autochthonous tumor cells. Vaccine-treated patients had advanced metastatic cancer but reacted to one or more common recall antigen skin tests. None of the 13 patients had untoward responses; 7/13 patients had classic delayed hypersensitivity reactions at the vaccine injection sites; and 2/7 patients with injection site reactions had significant reduction in tumor burden. These results indicate that this vaccine is a specific, active immune mechanism stimulator, and may prove to be a useful therapeutic agent in the treatment of human cancer.

Although the therapy of carcinoma of the colon and rectum has been investigated, little progress has been made in prolonging the survival in these patients. Specific active immunotherapy may provide the answer. Previous investigators have shown that colorectal cancer elicits an immune response and may be susceptible to immunologic manipulation. My laboratory has shown that a live vaccinia virus-augmented (vaccinia oncolysate) tumor cell vaccine is safe and may be worthwhile in the surgical adjuvant treatment of colorectal cancer. Nine patients with advanced cancer were treated. 0/9 showed adverse effect and 3/9 showed lack of progression of disease. Randomized prospective trials are now underway.

A live vaccinia virus-augmented tumor cell vaccine (vaccinia oncolysate) has been used as a specific active immune mechanism stimulator against certain advanced human cancers. This preliminary trial, in which the same dose of vaccinia oncolysate was used in 29 patients, showed the vaccine to be safe, non-toxic, and potentially effective. This study was designed as a toxicity/feasibility trial at a single vaccine dose. There was no effort to look at other dose levels. The heterogeneity of this early tumor group only reflects the type of patient available to the study during the early phase of vaccine testing. Randomized prospective trials have begun to make future analysis easier.

A Newcastle disease virus lysate of malignant melanoma cells was examined for its possible value in delaying the progression of malignant melanoma with palpable regional node disease (Stage II) to disseminated melanoma (Stage III). This Phase II study was carried out in a group of 32 patients following therapeutic lymphadenectomy. The patients were not prospectively randomized. In each patient, the viral oncolysate was administered subcutaneously at regular intervals over 3 years. The cumulated progressions to disseminated disease at 1, 2 and 3 years were 6%, 8% and 12% of the study group, respectively. These experienced losses were considerably lower than in the control group and in similar control groups described by other investigators. The results suggest that an oncolysate prepared with Newcastle disease virus is a helpful adjunct to surgery in the management of Stage II malignant melanoma.

Primary explants of human malignant melanoma were utilized in the preparation of oncolysates by Newcastle disease virus. The concentrated lysate, administered parenterally, was employed in an effort to augment antitumor immunologic responses in patients with metastatic melanoma. Observed cellular changes suggested a benefit, but humoral antibody measurements were not impressive.

Melanoma cell oncolysate, prepared with Newcastle disease virus, was administered as an immunostimulant to 13 patients with metastatic melanoma. The oncolysate was well tolerated. Six treated patients evidenced a decrease in the size of skin nodules or diseased lymph nodes. Visceral lesions were not favorably influenced to any marked degree. One case of fulminating disease showed a change to slow progression and survived a year longer than was otherwise expected. Another patient, whose melanoma could not be controlled by surgery or chemotherapy, has been in complete remission for 2 years. It appears that viral oncolysate might be particularly helpful to patients with early disease.

A2G mice could be solidly immunized against the Ehrlich ascites tumor by single intraperitoneal injections of homogenized and lyophilized tumor cells which had been infected with oncolytic strains of influenza A virus. Similar homogenates from noninfected tumor cells were not immunogenic, even when mixed with egg-grown virus. The immunizing principle in viral oncolysates could not be separated from the oncolytic virus by differential centrifugation or adsorption to and elution from red cells. It could be inhibited by antibody raised in rabbits against the egg-grown oncolytic virus. This reaction showed serologic specificity. Thus, the immunogenicity of an oncolysate produced with the WSA strain of neurotropic influenza virus could be inhibited by rabbit anti-WSA, but not by rabbit antibody to the TUR strain of fowl plague virus. Conversely, the immunogenicity of an oncolysate prepared with the TUR strain could be inhibited by rabbit anti-TUR, but not by anti-WSA. When mice were preimmunized (primed) with egg-grown WSA virus, their antitumor response to a later injection of WSA oncolysate was of the anamnestic type. Priming with egg-grown influenza B virus had no such effect. It was concluded that the immunogenicity of certain host cell components was greatly increased by incorporation into the makeup of the oncolytic virus.

In a study conducted since August 1974 by the Swiss Group for Clinical Cancer Research, 57 of 107 patients suffering from acute myelogenous leukemia achieved a complete remission. Thirty of these 57 patients were randomly selected to receive maintenance chemotherapy alone; the other 27 patients received, in addition to the same chemotherapy, monthly injections of viral oncolysate (i.e., formalin-treated fowl plaque virus-infected allogenous leukemia cells). The levels of antifowl plaque virus antibody titers in the sera were determined at regular intervals. All patients with an initial antibody titer of zero and a titer increase after the very first injection of oncolysate had remission times of less than six months (P less than or equal to 0.02). After the fifth injection there wa a clear reverse correlation of titer values and remission lengths (P less than or equal to 0.01). Several patients showed an association of changes of antiviral antibodies in the serum and the percentage of myeloblasts in the bone marrow. Immunization by viral oncolysate can therefore be used to predict the course of patients who are in remission from acute myelogenous leukemia; it may furthermore be helpful in detecting patients whose treatment has been insufficient.

• In this phase la/lb trial, vaccinia melanoma oncolysate (VMO) is a virus-augmented melanoma cell membrane vaccine that has been shown to be safe and to stimulate the production of antimelanoma antibodies in high-risk melanoma patients treated in a surgical adjuvant setting. One patient with stage I and 38 patients with stage II melanoma were entered in the study between December 1984 and October 1985, with a mean follow-up of approximately 17 months. Each patient received a smallpox booster injection followed one week later by the first of 13 weekly intradermal injections of 2.0 mg of VMO. At the end of 13 weeks, injections were given every other week for 12 months or until recurrence. Clinical results show that 25 of the 39 patients had no evidence of disease as of December 1986. Moreover and more importantly, statistical comparison of patients in this study with 39 matched controls shows a significant increase in disease-free survival for the patients treated with VMO. Serum obtained prior to treatment and at three-month intervals during treatment was tested in a Staphylococcus protein A rosette assay for reactivity with melanoma cell lines. All pretreatment samples (39/39) were negative, and 64% became positive by 12 months after appropriate dosage escalations. Moreover, enzyme-linked immunosorbent assay showed a positive correlation between antimelanoma IgG antibody titer and disease-free survival. ( Arch Surg 1987;122:1460-1463)

In Reply.— The letter by Dr Yettra reports another response of CLL to smallpox vaccination, although not as complete nor as long (our patient remains in complete remission now 4 ½ years after smallpox vaccination) as in our case. Of interest is the relatively rapid response over several months, suggesting lymphocyte destruction as the mechanism of action, rather than decreased production. Immunotherapy with any living organism is contraindicated in CLL because of risk of overwhelming infection. However, the demonstrated efficacy of vaccinia virus-lysed autochthonous tumor cell vaccine against other neoplasms is encouraging. 1 In view of these two proven responses of CLL to smallpox vaccination, a pilot study in patients with CLL, with vaccinia oncolysate as treatment, seems warranted.

To the Editor.— Hansen and Libnoch have recently described in theArchives(138:1137-1138, 1978) a patient with chronic lymphocytic leukemia (CLL) who attained a complete remission after smallpox vaccination. Proposed mechanisms for this remission included spontaneous regression, direct viral destruction of lymphocytes, and lymphocyte destruction through viral-induced host immune defenses. A trial of vaccinia oncolysate therapy for CLL was proposed. We wish to propose another mechanism for this remission: induction of endogenous interferon production. Interferon preparations have been shown to have both antiviral and antimitotic properties. 1,2 Viral infection induces host production of interferon. It has been shown that lymphocyte interferon production is increased in response to vaccinia antigen challenge. 3 Inhibition of the proliferation of tumor cells by interferon has been demonstrated with in vitro and in vivo animal systems. 2 Human malignancies have also responded to exogenous interferon treatment. 4 Interferon has been used as adjuvant therapy for