On the mode of action of intravesical bacillus Calmette-Guérin: in vitro characterization of BCG-activated killer cells

An armamentarium of wart treatments

Patients and clinicians experience the frustration of cutaneous viral warts caused by infection with the human papilloma virus (HPV).Warts appear in various forms on different sites of the body and include common warts (verruca vulgaris), plane or flat warts, myrmecia, plantar warts, coalesced mosaic warts, filiform warts, periungual warts, anogenital warts (venereal or condyloma acuminata), oral warts and respiratory papillomas. Cervical infection with HPV is now known to cause cervical cancer if untreated. A review of the medical literature reveals a huge armamentarium of wart monotherapies and combination therapies. Official evidence-based guidelines exist for the treatment of warts, but very few of the reported treatments have been tested by rigorous blinded, randomized controlled trials.Therefore, official recommendations do not often include treatments with reportedly high success rates, but they should not be ignored when considering treatment options. It is the purpose of this review to provide a comprehensive overview of the wart treatment literature to expand awareness of the options available to practitioners faced with patients presenting with problematic warts.

Cytokine gene polymorphisms can alter the effect of Bacillus Calmette-Guérin (BCG) immunotherapy

Various types of cancer are more frequent in men than women, and bladder cancer is one of the most common of these. Intravesical instillation of Bacillus Calmette-Guérin (BCG) after transurethral resection is the most effective treatment for superficial bladder cancers. The main aim of this study was to investigate for possible links between cytokine gene polymorphisms and different outcomes after BCG immunotherapy. Sixty patients who had been diagnosed with transitional cell cancer were investigated. All genotyping experiments were performed using polymerase chain reaction sequence-specific primers and a commercially available kit. The genes investigated were those that code for interleukin (IL)-1alpha, IL-1beta, IL-1R, IL-1RA, IL-4RA, IL-2, IL-4, IL-6, IL-10, IL-12, interferon-gamma (IFN-gamma), transforming growth factor-beta (TGF-beta), and tumor necrosis factor-alpha (TNF-alpha). Analyses of the data identified TGF-beta codon 25 GG (92.85% vs. 64.44%, p=0.04, OR=7.17), IL-4 -1098 GG (16.6% vs. 0.0%, p=0.05, OR=18.33), IL-10 -1082 GG (28.5% vs. 6.8%, p=0.05, OR=5.47), and IL-10 -1082 GCC/GCC (28.57% vs. 4.5%, p=0.025, OR=8.4) polymorphisms as risk factors for progression of bladder cancer.

Interaction between photodynamic therapy and BCG immunotherapy responsible for the reduced recurrence of treated mouse tumors

Subcutaneous mouse EMT6 tumors were treated by individual or combined regimens of a single Bacillus Calmette-Guérin (BCG) vaccine administration and photodynamic therapy (PDT). Six clinically relevant photosensitizers characterized by different action mechanisms were used: Photofrin, benzoporphyrin derivative, tetra(m-hydroxyphenyl)chlorin (foscan), mono-L-aspartylchlorin e6, lutetium texaphyrin or zinc phthalocyanine. Irrespective of the type of photosensitizer used, the optimized BCG protocols improved the cure rate of PDT-treated tumors. This indicates that the interaction does not take place during the early phase of tumor ablation but at later events involved in preventing tumor recurrence. Beneficial effects on tumor cure were observed even when the BCG injection was delayed to 7 days after PDT. The accumulation of activated myeloid cells that markedly increases in tumors treated by Photofrin-based PDT was not additionally affected by BCG treatment. However, the incidence of immune memory T cells in tumor-draining lymph nodes that almost doubled at 6 days after Photofrin-PDT further increased close to three-fold with adjuvant BCG. This suggests that BCG immunotherapy amplifies the T-lymphocyte-mediated immune response against PDT-treated tumors. Since both these modalities are established for the treatment of superficial bladder carcinomas, use of their combination for this condition should be clinically tested.

Reduction of side effects of intravesical therapy with bacille Calmette-Guérin by pentoxifylline?--an in vitro approach

Immunotherapy with intravesical bacille Calmette-Guérin (BCG) is the treatment of choice against superficial bladder cancer recurrences. However, this therapy is associated with side effects that are considered to be the result of inflammatory cytokines. Since pentoxifylline is known to interfere with the production of cytokines, this drug was tested in vitro with regard to a later clinical application in BCG-treated patients. The cytokine release and the cytotoxicity of interleukin-2 or BCG-stimulated mononuclear cells were analyzed, and the growth of BCG under the influence of pentoxifylline was assayed. The results showed an inhibition of cytokine release of stimulated mononuclear cells. The cytotoxicity of BCG-stimulated mononuclear cells but not of lymphokine-stimulated mononuclear cells against bladder carcinoma cells was significantly inhibited. Restimulation with fresh BCG restored cytotoxicity. Direct coincubation of BCG and pentoxifylline resulted in a reduction of mycobacterial metabolism. From these data, we conclude that the use of pentoxifylline to reduce BCG-related side effects should be tested further in a clinical study.

Non-specific, rapidly generated cytotoxicity in lymphocytes induced by BCG in vitro: no evidence of enhancing effect from preceding interaction between BCG and transitional cell line cells

PURPOSE

To study short-term events in the mechanism of action of BCG with an emphasis on the interaction between BCG and T24 cell line cells.

MATERIALS AND METHODS

Peripheral blood mononuclear cells (PBMNC) or/and several tumor cell lines were incubated with BCG (Oncotice) using various clinical and subclinical BCG concentrations.

RESULTS

3 h BCG incubation of PBMNC at 10(7) - 5*10(5) CFU/ml., followed by a 4 h cytotoxicity test, resulted in a significant augmentation of cytotoxicity of PBMNC against T24 cells, and the augmentation was almost significant at 10(5) CFU/ml. Overnight BCG incubation of PBMNC further augmented that cytotoxicity at all concentrations down to 10(4) CFU/ml. The minimum overall time (incubation with BCG + cytotoxicity test), where stimulation of PBMNC could be detected, was only 4 h. The BCG enhanced cytotoxicity of PBMNC could be demonstrated against all the tested cell line cells in a 4 h cytotoxicity test by using a preceding overnight BCG incubation of PBMNC, and against the majority of the cell lines by using a preceding 3 h BCG incubation of PBMNC. No convincing evidence was obtained to support the hypothesis that BCG should be first processed by T24 cells to make these cells more susceptible to cell mediated lysis by PBMNC.

CONCLUSIONS

Clinical and subclinical concentrations of BCG are directly stimulatory to PBMNC, which become, in a minimum time of a few hours, more capable of killing tumor cells, without a need for preceding interaction between BCG and tumor cells.

Epididymo-orchitis and Reiter's disease. Two infrequent complications after intravesical bacillus Calmette-Guérin therapy

Two cases of adverse reactions to intravesical treatment with bacillus Calmette-Guérin are reported. The first patient presented with a severe suppurating epididymo-orchitis three months after his last treatment. The second patient developed Reiter's disease with arthritis of one knee and conjunctivitis 1 week after the fourth instillation.