The re-emergence of thalidomide: results of a scientific conference

Assessing advantages of sequential boron neutron capture therapy (BNCT) in an oral cancer model with normalized blood vessels

BACKGROUND

We previously demonstrated the therapeutic success of sequential boron neutron capture therapy (Seq-BNCT) in the hamster cheek pouch oral cancer model. It consists of BPA-BNCT followed by GB-10-BNCT 24 or 48 hours later. Additionally, we proved that tumor blood vessel normalization with thalidomide prior to BPA-BNCT improves tumor control. The aim of the present study was to evaluate the therapeutic efficacy and explore potential boron microdistribution changes in Seq-BNCT preceded by tumor blood vessel normalization.

MATERIAL AND METHODS

Tumor bearing animals were treated with thalidomide for tumor blood vessel normalization, followed by Seq-BNCT (Th+ Seq-BNCT) or Seq-Beam Only (Th+ Seq-BO) in the window of normalization. Boron microdistribution was assessed by neutron autoradiography.

RESULTS

Th+ Seq-BNCT induced overall tumor response of 100%, with 87 (4)% complete tumor response. No cases of severe mucositis in dose-limiting precancerous tissue were observed. Differences in boron homogeneity between tumors pre-treated and not pre-treated with thalidomide were observed.

CONCLUSION

Th+ Seq-BNCT achieved, for the first time, response in all treated tumors. Increased homogeneity in tumor boron microdistribution is associated to an improvement in tumor control.

Rheumatic manifestations of human immunodeficiency virus infection

Rheumatic complaints are common in patients with HIV, and HIV positivity confers an increased susceptibility in populations with similar risk factors for HIV infection. With the advent of the modern combined antiretroviral treatment, HAART has had a profound beneficial effect on survival in HIV-infected patients, with lifelong control of HIV infection and normalization of life expectancy; but it has also contributed to both an altered frequency and a different nature of rheumatic complications now being observed in this population, with new rheumatic complications, such as osteoporosis, osteonecrosis, gout, mycobacterial, mycotic osteoarticular infections, and neoplasia perhaps more prevalent. Rheumatologists, internists, and general physicians need to be aware of these changes to provide optimal diagnosis and how to disclose the results to their patients. They also need to be familiar with the management of HIV infection and to direct careful attention to the prevention of HIV transmission in health care facilities.

Talidomida no tratamento do eritema nodoso hansênico: revisão sistemática dos ensaios clínicos e perspectivas de novas investigações

FUNDAMENTOS: A hanseníase persiste como problema de saúde pública, e episódios de ENH são eventos agudos que ocorrem antes, durante e após PQT. Na última década, o uso da talidomida como agente imunomodulador foi expandido a outras doenças. OBJETIVOS: realizar revisão sistemática dos ensaios clínicos publicados sobre a eficácia e efeitos colaterais da talidomida no ENH. Descrever metodologia e resultados da triagem para recrutamento de ensaio clínico visando avaliar dose-resposta da talidomida seguida de desmame no ENH moderado e grave, realizado no Brasil. MÉTODOS: Analisaram-se ensaios publicados sobre talidomida no ENH. Foi delineado um ensaio clínico duplo-cego randomizado para avaliar dose de 100 thalid 300mg/dia de talidomida durante fase aguda de ENH, seguida de desmame da talidomida, thalid placebo. Para este ensaio clínico descreve-se metodologia e dados de recrutamento de pacientes, com ênfase na gravidade dos episódios de ENH. RESULTADOS: Os seis ensaios clínicos publicados nas décadas de 1960 e 1970 apontam para o benefício da talidomida no ENH, embora diferenças metodológicas dificultem a comparação. Na fase de recrutamento do ensaio brasileiro, dos 143 pacientes de ENH triados, 65% eram potencialmente elegíveis. A associação com neurite em 56,4% dos ENH moderados e graves exigiu co-intervenção com corticosteróide. CONCLUSÃO: O padrão de recrutamento dos pacientes evidenciou alta freqüência de neurite nos episódios de ENH. O esquema de talidomida isolada no ENH foi avaliado como infreqüente na prática clínica brasileira. O desafio atual é acumular evidências sobre a eficácia e efeitos colaterais da talidomida em associação com corticosteróides.

Assessing Maternal Genetic Associations

BACKGROUND

In utero exposures, including maternal phenotypes, are potential risk factors for both early-onset and adult-onset diseases. Two alternative study designs use maternal genotypes at polymorphic loci as biomarkers of an offspring's in utero exposure: (1) a traditional case-control study with logistic regression analysis, in which cases, controls, and mothers of both types of subjects are genotyped; and (2) a case-parent triad study with log-linear analysis, in which cases and both parents are genotyped.

METHODS

We used computer simulations to compare the operating characteristics of the log-linear approach to case-parent triad data and the case-control approach for assessing relative risks (RRs) associated with maternal genotypes.

RESULTS

For high-risk allele frequencies (chromosomal prevalence; f) between 0.20 and 0.75, both methods allowed for valid, unbiased estimates of maternal RRs. The case-parent triad approach, however, had 43% greater power, on average, than the case-control approach with an equal number of genotypes, and 13% greater power with an equal number of cases. For example, under dominant inheritance, to detect 2-fold maternal RRs with 200 (or 150) cases when allele prevalence is between 0.15 and 0.40, the case-parent triad and equal-genotype case-control designs had, on average, 87% and 62% power, respectively. As f approached 0 or 1, the power of both methods decreased sharply.

DISCUSSION

The greater efficiency of case-parent triads may be due to the inclusion of paternal genotype information, which allows for independent tests of disease association with maternal or offspring genotypes. These results highlight one potential advantage of case-parent triad data in assessing maternal genetics as risk factors for offspring disease. We discuss these findings and other considerations between the 2 methodological approaches.

Crohn's disease: future anti-tumor necrosis factor therapies beyond infliximab

The dramatic benefit experienced by many Crohn's disease patients treated with the anti-tumor necrosis factor-alpha (TNF-alpha) antibody infliximab underscores the centrality of this cytokine in the pathogenesis of Crohn's disease and the potential use of the therapeutic strategy of blocking TNF-alpha in this disease. In the hopes of emulating and improving on the success of infliximab, numerous strategies are being devised and studied to inhibit the actions of TNF-alpha. This article focuses on those agents, other than infliximab, which target TNF-alpha to treat inflammatory bowel disease as their central mechanism of action.

An investigation of the effect of thalidomide on anti-gal antibody production in baboons

Previous data suggest that natural anti-Galalpha1,3Gal (Gal) antibody (Ab) is produced by mature plasma cells. As thalidomide is effectively used in the treatment of patients with multiple myeloma, its effect on natural anti-Gal Ab production has been assessed in two baboons. During a 10-week course of thalidomide administration (until it reached toxic levels in one baboon), there was no major reduction in Ab levels or in their rate of return after a course of extracorporeal immunoadsorption. A significant reduction of CD3+ cells (75%), and particularly of CD4+ cells (65 to 95%), was measured in the blood by flow cytometry. This was associated with general hyporesponsiveness on mixed lymphocyte reactivity in one baboon, but not in the other. Thalidomide would appear to have little effect on the production of natural Ab, but these observations lend some support to previous work by others indicating that thalidomide may suppress the cellular response to an allograft or xenograft.

Thalidomide and its derivatives: emerging from the wilderness

Forty years on from its worldwide withdrawal, thalidomide is currently undergoing a remarkable renaissance as a novel and powerful immunomodulatory agent. Over the last decade it has been found to be active in a wide variety of inflammatory and malignant disorders where conventional therapies have failed. Recently, considerable progress has been made in elucidating its complex mechanisms of action, which include both anticytokine and antiangiogenic properties. However, in addition to its well known teratogenic potential, it has a significant side effect profile that leads to cessation of treatment in up to 30% of subjects. In response to this, two new classes of potentially safer and non-teratogenic derivatives have recently been developed. This review summarises the biological effects, therapeutic applications, safety profile, and future potential of thalidomide and its derivatives.

Rheumatic manifestations of human immunodeficiency virus infection

Rheumatic complaints are common in patients with human immunodeficiency virus (HIV) infection. With the advent of the modern combined antiretroviral treatment, life-long control of HIV infection and normalization of life expectancy in HIV-positive patients have become realistic perspectives, but new rheumatic complications, such as osteoporosis, osteonecrosis, gout, and mycobacterial and mycotic osteoarticular infections may be more prevalent. Rheumatologists, internists, and general physicians need to be familiar with the presentation and treatment of these conditions in HIV-positive patients.

Thalidomide: a role in oral oncology?

Thalidomide is having increasing application in the management of a wide spectrum of immunologically-mediated and infectious disorders. It is also suggested that this agent may also have be of importance in the treatment of solid and non-solid malignancies. The present article reviews the role of thalidomide in the management of malignancy and outlines its possible potential in the treatment of malignancy of the mouth.

Evolving new therapies of autoimmune hepatitis

Refinements in the understanding of the mechanisms of immunocyte activation and the emergence of new immunosuppressive agents with highly selective actions has created opportunities for improving the treatment of autoimmune hepatitis. Drugs, such as budesonide and deflazacort, may inhibit immunocyte activation and limit corticosteroid-related side effects. Agents, such as cyclosporine and tacrolimus, can impair calcineurin activity and restrict the generation of transcription factors necessary for T cell responses. Intravenous immunoglobulin can bind anti-idiotype antibodies and reduce interleukin-2 secretion, and monoclonal antibodies directed against critical components of the T cell activation cascade can dampen the immune reaction. Drugs, such as mycophenolate mofetil, cyclophosphamide, methotrexate, and KF20444, can inhibit T cell proliferation, and other interventions promise to deplete activated T cells, impair effector mechanisms, and induce self-tolerance.

Drug-induced congenital defects: strategies to reduce the incidence

Approximately 1% of congenital anomalies relate to pharmacological exposure and are. in theory, preventable. Prevention consists of controlled administration of drugs known to have teratogenic properties (e.g. retinoids, thalidomide). When possible, prevention could take the form of the use of alternative pharmacological therapies during the pre-conception period for certain specific pathologies, selecting the most appropriate agent for use during pregnancy [e.g. haloperidol or a tricyclic antidepressant instead of lithium; anticonvulsant drug monotherapy in place of multitherapy; propylthiouracil instead of thiamazole (methimazole)], and substitution with the most suitable therapy during pregnancy (e.g. insulin in place of oral antidiabetics; heparin in place of oral anticoagulants; alpha-methyldopa instead of ACE inhibitors). Another strategy is the administration of drugs during pregnancy taking into account the pharmacological effects in relation to the gestation period (e.g. avoidance of chemotherapy during the first trimester, avoidance of nonsteroidal anti-inflammatory drugs in the third trimester, and avoidance of high doses of benzodiazepines in the period imminent to prepartum).

Antitumorigenic Evaluation of Thalidomide Alone and in Combination with Cisplatin in DBA2/J Mice

Thalidomide's reported ability to inhibit angiogenesis has led to clinical trials determining its effectiveness in combating various types of cancer. This study explored thalidomide's antitumorigenic potential when administered alone and in combination with cisplatin to DBA2/J mice whose tumors were induced by murine erythroleukemic cells. Thalidomide treatment alone produced no significant inhibitory effect on tumor development and metastasis. Mice that received both drugs had significantly lower incidences of both primary and secondary tumors as compared to the untreated control group. Cisplatin, administered alone or in combination with thalidomide, led to a significant delay in tumor formation and a longer life span than was recorded in untreated mice. However, the combination treatment results were not significantly different from those of cisplatin treatment used as a single agent. In in vitro cell multiplication studies using murine erythroleukemic and murine endothelial cells, thalidomide failed to inhibit cell proliferation. However, cisplatin treatment with or without thalidomide, significantly inhibited the multiplication of both cell lines in a dose dependent manner. Thalidomide does not appear to be a beneficial adjuvant to cisplatin treatment.

Thalidomide: dual benefits in palliative medicine and oncology

Thalidomide is an immunomodulator, anti-angiogenic agent, anti-cytokine, and anti-integrin. Alone or in combination with other drugs, thalidomide has also demonstrated anti-cachexin and anti-neoplastic properties. Anorexia and cachexia are common symptoms of advanced cancer. Since certain cytokines also promote tumor growth, we may have a class of agents with palliative and anti-tumor benefits in combination with anti-neoplastics and anti-cytokines, such as thalidomide.