Six-step etoposide desensitization protocol: A pediatric, adolescent, and young adult case series.

Etoposide administration can be complicated by hypersensitivity reactions. Desensitization may provide a strategy to prevent hypersensitivity recurrence. One challenge with desensitization is regimen complexity. This case series describes 12 pediatric, adolescent, and young adult patients who received a simplified six-step etoposide desensitization protocol. This protocol contains 50% fewer titration steps compared with previously described protocols and eliminates infusion rate changes during titration. Simplified titration may minimize risk of error during administration and improve safety. This protocol was tolerated by 92% of patients. Given increasing frequency and duration of drug shortages, a simplified desensitization protocol provides a valuable treatment option.

Review of hypersensitivity reactions to antineoplastic agents.

OBJECTIVE: To review the characteristics and management of hypersensitivity reactions caused by antineoplastic agents. METHOD: We conducted a search in the Pubmed and EMBASE databases for the last 10 years. RESULTS: Almost all chemotherapeutic agents have the potential to cause hypersensitivity reactions, but some groups have been associated with increased risk, such as platinum compounds, taxanes, asparaginase, monoclonal antibodies and epipodophyllotoxins. The clinical manifestations of these reactions are variable and unpredictable, including symptoms affecting the skin and the pulmonary, cardiac and gastrointestinal systems. The mechanism associated with their development is not yet fully understood. Diagnosis is based on patients' signs and symptoms and skin testing. The management of patients who suffer a hypersensitivity reaction to a chemotherapeutic agent varies with the severity of the reaction, the need to continue treatment, and the availability of alternative therapies. CONCLUSIONS: Due to a progressive increase in the use of chemotherapeutic agents an increased incidence of hypersensitivity reactions is to be expected. Desensitisation protocols are a noteworthy alternative that make it possible to re-initiate patients' therapy with the causative agent of the hypersensitivity reaction. Their use should be assessed individually, weighing risks and benefits.

Simultaneous evaluation of viability and Bcl-2 in small-cell lung cancer.

When designing molecular targeted therapeutic strategies against cancer, it is important to correlate protein expression and cell viability. However, such goal can be difficult if performed in separate assays, especially when only a fraction of cells has been efficiently transfected. Therefore, the aim of the present study was to establish a flow cytometry procedure to assess simultaneously Bcl-2 protein level and viability in small-cell lung cancer (SCLC) cells. Viability assessment was performed by staining cells with Annexin V-fluorescein isothiocyanate (FITC) and 7-aminoactinomycin D (7-AAD). Intracellular detection of Bcl-2 was carried out by immunodetection with monoclonal antibodies. Regarding viability determination, the FSC/7-AAD plot identifies the same percentage of viable cells as the FSC/Annexin V-FITC plot, although with greater sensitivity. The procedures involving cells' fixation with 1% paraformaldehyde and permeabilization with digitonin, required for intracellular Bcl-2 immunostaining did not compromise the association of 7-ADD (nor Annexin V-FITC) previously incubated with SCLC cells. It was therefore possible to simultaneously assess cell viability and Bcl-2 protein in SCLC cells. A simple, sensitive, and versatile procedure was established for the first time for the simultaneous evaluation of cell viability and intracellular detection of Bcl-2 in SCLC.

Alpha(4)beta(7)/alpha(4)beta(1) dual integrin antagonists block alpha(4)beta(7)-dependent adhesion under shear flow.

The alpha(4) integrin, alpha(4)beta(7), plays an important role in recruiting circulating lymphocytes to the gastrointestinal tract, where its ligand mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is preferentially expressed on high endothelial venules (HEVs). Dual antagonists of alpha(4)beta(1) and alpha(4)beta(7), N-(2,6-dichlorobenzoyl)-(L)-4-(2',6'-bis-methoxyphenyl)phenylalanine (TR14035) and N-(N-[(3,5-dichlorobenzene)sulfonyl]-2-(R)-methylpropyl)-(D)-phenylalanine (compound 1), were tested for their ability to block the binding of alpha(4)beta(7)-expressing cells to soluble ligand in suspension and under in vitro and in vivo shear flow. Compound 1 and TR14035 blocked the binding of human alpha(4)beta(7) to an (125)I-MAdCAM-Ig fusion protein with IC(50) values of 2.93 and 0.75 nM, respectively. Both compounds inhibited binding of soluble ligands to alpha(4)beta(1) or alpha(4)beta(7) on cells of human or rodent origin with similar potency. Under shear flow in vitro, TR14035 and compound 1 blocked binding of human alpha(4)beta(7)-expressing RPMI-8866 cells or murine mesenteric lymph node lymphocytes to MAdCAM-Ig with IC(50) values of 0.1 and 1 microM, respectively. Intravital microscopy was used to quantitate alpha(4)-dependent adhesion of fluorescent murine lymphocytes in Peyer's patch HEVs. When cells were prestimulated with 2 mM Mn(2+) to activate alpha(4)beta(7) binding to ligand, anti-alpha(4) monoclonal antibody (mAb) [10 mg/kg (mpk) i.v.] blocked adhesion by 95%, and anti-beta(1) mAb did not block adhesion, demonstrating that this interaction was dependent on alpha(4)beta(7). TR14035 blocked adhesion to HEVs [ED(50) of 0.01-0.1 mpk i.v.], and compound 1 blocked adhesion by 47% at 10 mpk i.v. Thus, alpha(4)beta(7)/alpha(4)beta(1) antagonists blocked alpha(4)beta(7)-dependent adhesion of lymphocytes to HEVs under both in vitro and in vivo shear flow.

Bleomycin-induced hyperpigmentation and hypersensitivity reactions to etoposide and vinblastine in a child with endodermal sinus tumor.

We report a pediatric case who developed bleomycin-induced hyperpigmentation and hypersensitivity reactions to both etoposide and vinblastine while receiving chemotherapy for germ cell tumor. Skin hyperpigmentation related to chemotherapeutic agents has been reported only rarely in pediatric patients. This patient developed a characteristic skin hyperpigmentation which was "flagellate" in appearance. Two features of the hyperpigmentation were noteworthy: development at a low cumulative dose of bleomycin and persistence after cessation of chemotherapy. Additive effect of cisplatinum-induced hyperpigmentation was suggested. Although hypersensitivity reactions to etoposide have been previously reported, hypersensitivity reactions to vinblastine are almost unknown. To our knowledge, this is the first report of hypersensitivity reaction to vinblastine in a child in English literature.

A highly sensitive enzyme-linked immunosorbent assay for etoposide using beta-D-galactosidase as a label.

A highly sensitive enzyme-linked immunosorbent assay (ELISA) for etoposide (EP) was developed, which is capable of accurately measuring as little as 40 pg EP/ml. Anti-EP sera were obtained by immunizing rabbits with EP conjugated with mercaptosuccinyl bovine serum albumin (MS.BSA) using N-[beta-(4-diazophenyl)ethyl]maleimide (DPEM) as a heterobifunctional coupling agent. An enzyme marker was similarly prepared by coupling EP with beta-D-galactosidase (beta-Gal; EC 3.2.23) via DPEM. This ELISA was specific for EP and showed a very slight cross-reactivity with its major metabolite, cis-hydroxy acid of EP (0.91%), but none with 4'-demethylepipodophyllotoxin and drugs commonly used with EP in combination chemotherapy for cancer treatment. The values for EP concentration detected by this assay were comparable with those detected by the high-performance liquid chromatography (HPLC) method. However, the ELISA was about 1,250 times more sensitive in detecting EP at lower concentrations. Using this assay, drug levels were easily determined in the blood and urine of rats for 7 h after i.v. administration of EP at a single dose of 3 mg/kg. Due to its sensitivity and specificity for EP, the ELISA should prove to be a valuable new tool for use in clinical pharmacological studies.

Immunocytochemical localisation of VP16-213 in normal and malignant tissues.

Immunocytochemistry has been used to visualise the distribution of the anti-cancer drug VP16-213 in tissues from normal and leukaemic mice, and in EMT6 mammary tumours. Uptake of the drug into EMT6 tumour tissue was poor compared to uptake into normal tissues (liver, kidney, heart, small intestine). Uptake of the drug into tissues from L1210 mice was greater than that into normal tissues. Immunocytochemistry promises to be a very useful additional technique for studying the distribution of drugs given singly or in combination, specific organ toxicities, and mechanisms of resistance.