Prophylactic vaccines against cancers of non-infectious origin: a dream or a real possibility?

The dramatic progress in tumour biology and immunology in the past several years has opened new avenues for the treatment and prevention of cancer. One of the great contributions of the immunotherapeutic approaches is an increasing understanding of the immunology of cancer, which is, gradually creating conditions for the development of prophylactic anti-cancer vaccines. Efficient vaccines have been developed and employed for the prophylaxis of two frequent cancers of viral origin, namely cervical cancer and liver cancer.

Intracellular Cytokines Produced by Stimulated CD3+ Cells from Chronic Myeloid Leukemia Patients.

Our work examined the production of intracellular interferon (INF)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-2, and IL-4 by in vitro stimulated CD3+ cells from 38 chronic myeloid leukemia (CML) patients. At the time of diagnosis the percentages of cells producing INF-γ, TNF-α, and IL-2 were strongly suppressed compared to those in healthy control subjects. Hematological remission achieved through treatment with tyrosine-kinase inhibitors was associated with a highly significant increase in the ratio of cells producing all 4 cytokines.

The Relationship of Kynurenine and Neopterin Levels and Their Association with a Selection of Other Immune Markers in Chronic Myeloid Leukaemia Patients.

Among malignant diseases, chronic myeloid leukaemia (CML) is one of the best suited candidates for immunotherapy. For this purpose it is necessary to broaden the present knowledge on the immunology of this disease. As a part of such a project, the levels of kynurenine (KYN) and neopterin (NPT) were studied in 28 CML patients and in the same number of healthy subjects.

Predictive value of serum cytokine levels in chronic myeloid leukemia patients.

Serum samples taken at diagnosis in 28 chronic myeloid leukemia patients were tested for the presence of 20 cytokines by a magnetic bead-based Bio-plex immunoassay. According to complete cytogenetic remission achieved at 12 months of treatment, patients were divided into groups with either optimal or non-optimal outcome. Patients with increased cytokine levels tended to react optimally to the therapy more frequently than those others.

[Indoleamine 2,3-dioxygenase in oncology and psychiatry].

In the last years an attention has been paid to the indoleamine 2,3-dioxygenase (IDO), an enzyme catabolising L-tryptophan to kynurenine. Growing evidence has been accumulated that kynurenine and other metabolites of tryptophan play an important role in the pathogenesis of malignant tumours and some neurological and psychiatric disorders. The gradual recognition of mechanisms operative in their development may help to identify etiological factors involved and becomes prerequisite for the progress in their diagnostics and therapy.

Kynurenine and uric acid levels in chronic myeloid leukemia patients.

Indoleamine 2,3-dioxygenase 1 (IDO1), IDO2 and tryptophan 2,3-dioxygenase (TDO) represent some of the key immune regulators. Their increased activity has been demonstrated in a number of human malignancies but not yet in chronic myeloid leukemia (CML). In the present study, the activity of these enzymes was tested in 29 CML patients and 28 healthy subjects by monitoring the kynurenine (KYN)/tryptophan ratio.

Immunology of chronic myeloid leukemia: current concepts and future goals.

Although chronic myeloid leukemia is a rare malignancy, it has developed into a model system for the study of a variety of aspects of cancer biology and immunology. The introduction of tyrosine kinase inhibitors has resulted in a significant prolongation of the survival rates of chronic myeloid leukemia patients but has not resulted in a cure. There is a growing conviction that this aim can be achieved through immunotherapy.

Administration of a plasmid that expresses SDF-1α affects the oncogenic potential of mouse bcr-abl-transformed cells.

Stromal-derived factor 1α (SDF‑1α, also known as CXCL12) is a chemokine that exerts its effects through the G-protein coupled receptors, C-X-C chemokine receptor type 4 (CXCR4) and 7 (CXCR7). There is marked evidence that the SDF-1/CXCR4 axis is involved in the pathogenesis of leukemia and therapies that target this axis are under development. The present study aimed to increase the efficacy of a DNA-based bcr-abl vaccine by simultaneously immunizing mice with a plasmid carrying the whole SDF-1α gene.

Tumor protective activity of CD4+ but not of CD8+ T cells in DNA-vaccinated mice challenged with bcr-abl-transformed cells.

In the recent past, it has repeatedly been reported that CD4 cells play an important role in the immunology of chronic myeloid leukaemia. It was therefore of interest to test their activity in an animal model using bcr-abl-transformed cells. BALB/c mice were four times immunized with a DNA vaccine carrying the bcr-abl fusion gene.

Properties of bcr-abl-transformed mouse 12B1 cells secreting interleukin-2 and granulocyte-macrophage colony stimulating factor (GM-CSF): II. Adverse effects of GM-CSF.

Granulocyte-macrophage colony stimulating factor (GM-CSF) is considered to be the most effective immunostimulating factor for the construction of gene-engineered anti-cancer vaccines. In some tumour cells, this type of genetic modification has resulted in the loss of the oncogenic potential. This was not the case with bcr-abl-transformed mouse 12B1 cells.

Properties of bcr-abl-transformed mouse 12B1 cells secreting interleukin-2 and granulocyte-macrophage colony-stimulating factor: I. Derivation, genetic stability, oncogenicity and immunogenicity.

The highly oncogenic bcr-abl-transformed mouse (Balb/c) 12B1 cells were transfected with plasmids carrying genes for either mouse interleukin-2 (IL‑2) or the mouse granulocyte-macrophage colony-stimulating factor (GM‑CSF) and the gene for blasticidine resistance. From the transduced cells several clones widely differing in the production of either cytokine were isolated. For further experiments, clones with the highest secretion of the cytokines were selected.

Unexpected properties of endostatin-producing mouse BCR-ABL-transformed cells.

We investigated whether a genetic modification of BCR-ABL-transformed mouse cells that resulted in endostatin (ES) production altered their oncogenic potential. Mouse B210 cells, which express p210bcr-abl fusion protein and induce leukemia-like disease and extremely rarely solid tumors after intravenous (i.v.

Changes of immunological profiles in patients with chronic myeloid leukemia in the course of treatment.

In the previous paper of ours we compared, prior to start any treatment, a number of immunological parameters in 24 chronic myeloid leukemia patients with the same number of healthy subjects matched by age and sex. We found significant differences in the levels of immunoglobulins, the C4 component of complement, the C-reactive protein, interleukin 6, the composition of lymphocyte population and the production of some cytokines by stimulated CD3+ cells. Eleven of these patients were followed longitudinally.

[Will vaccines appear on the scene of oncology in the near future?].

In parallel with the increasing knowledge of the role played by the immune system in the control oftumourgrowth, the efforts to develop anti-cancer vaccines intensify. In the present time two highly efficient prophylactic vaccines against the virus-induced cancers are in use, but a rapid progress in the development of anti-cancer therapeutic vaccines can also be seen. It is conditioned by an increasing understanding of the biology of the tumor cells and the rapid progress in the field of immunology.

Immunotherapy of chronic myeloid leukemia: present state and future prospects.

In spite of the considerable successes that have been achieved in the treatment of chronic myeloid leukemia (CML), cure for the disease can only be obtained by the present means in a rather small minority of patients. During the past decade, considerable progress has been made in the understanding of the immunology of CML, which has raised hopes that this disease may be curable by supplementing the current targeted chemotherapy with immunotherapeutic approaches. More than ten small-scale clinical trials have been carried out with experimental vaccines predominantly based on the p210bcr-abl fusion protein.

In vitro and in vivo effects of reovirus on HPV16-transformed mice cells.

Unlabelled: Oncolytic viruses are examined to serve as anticancer therapeutics. It is expected that in addition to direct oncolytic effect their action will also help eliciting a solid antitumor immunity. In presented series of experiments we have employed two HPV16-transformed mouse (strain C57/B6) cell lines, TC-1 and MK16/III/ABC (MK16), and reovirus type 3, strain Dearing (RV).

Bcr-Abl fusion sequences do not induce immune responses in mice when administered in mouse polyomavirus based virus-like particles.

Mouse polyomavirus-like particles (MPyV-VLPs) carrying inside a fragment of the Bcr-Abl hybrid protein containing the epitope of chronic myeloid leukemia fusion region were prepared. A sequence encoding 171 amino acids covering Bcr-Abl breakpoint was fused to the C-terminal part of VP3 minor protein connecting it to the VP1 capsomeres. Chimeric particles, the Bcr-Abl VLPs, were tested for their ability to induce Bcr-Abl specific immune response in mice after their intranasal (i.

DNA vaccination against bcr-abl-positive cells in mice.

A series of DNA vaccines based on the bcr-abl fusion gene were developed and tested in mice. Two mouse (BALB/c) bcr-abl-transformed cell lines, B210 and 12B1, which both expressed p210bcr-abl and were oncogenic for syngeneic animals but differed in some other respects, were used as a model system. In the first series of experiments, plasmids carrying either the complete bcr-abl fusion gene or a fragment thereof coding for a 25-amino acid-long junction zone (bcr-abl25aa) linked with genes coding for a variety of immunostimulatory factors were used as the DNA vaccines.

Effects of endostatin production on oncogenicity and metastatic activity of HPV16-transformed mouse cells: role of interleukin 1alpha.

Two mouse HPV16-transformed cell lines, viz. MK16 cells, which induce metastasizing tumors, and TC-1 cells, which induce non-metastasizing tumors were transduced with the gene for mouse endostatin. Two clones constitutively expressing endostatin were isolated from each of them.

Isolation and properties of gene-modified mouse bcr-abl-transformed cells expressing various immunostimulatory factors.

Unlabelled: B210 cells are murine (BALB/c) cells transformed by bcr-abl fusion gene. After intravenous administration they are capable of inducing leukaemia-like disease in syngeneic mice. From these cells a thymidine-kinase less subline was derived.

Combined chemo- and immunotherapy of tumors induced in mice by bcr-abl-transformed cells.

For our experiments we selected two oncogenic, bcr-abl-transformed mouse cell lines, viz. B210 and 12B1. Both cell types are capable of inducing leukemia-like disease in syngeneic BALB/c mice after intravenous inoculation.

Efficacy of reovirus therapy combined with cyclophosphamide and gene-modified cell vaccines on tumors induced in mice by HPV16-transformed cells.

Oncolytic virotherapy is a novel approach to cancer treatment. In the present study we tested the ability of reovirus type 3, strain Dearing, to suppress the growth of tumors induced in mice by HPV16-transformed TC-1 cells. In vitro, these cells are highly susceptible to the virus.

Human hair follicle and interfollicular keratinocyte reactivity to mouse HPV16-transformed cells: an in vitro study.

The role of stem cells in cancer formation and spreading has been established. As with normal tissue, the cancer stem cells need a special microenvironment to support their growth. This microenvironment may be represented by the tumor stroma.

Vaccines against human papillomaviruses--a major breakthrough in cancer prevention.

Carcinoma of the cervix (CaCer) is the second most frequent malignancy in women on a global scale. Epidemiological studies carried out at the beginning of the second half of the 20th century showed that CaCer was of infectious nature and that its agent was transmitted by sexual intercourse. For some 15 years, herpes simplex virus type 2 (HSV2), the genital herpes virus, was suspected to be the etiological agent.