Toxicity and efficacy profiles of intrathecal injection of I-131 NaI via intraventricular (IVent) or intralumbar (Ilumb) route for leptomeningeal metastases (LM) therapy

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Background: LM is a fatal complication occurring in up to 30% of cancer patients. Intrathecal chemotherapy of LM is limited by diffusion while external beam irradiation is limited by neurotoxicity. Radioiodine I-131 may serve as a ablating agent because of its radiations transverse the meningeal thinkness but spare distant underlying nervous tissues. Two phase I studies are designed to determine MTD and to evaluate potential toxicity and efficacy of intrathecal I-131 sodium iodide (NaI) injected via IVent or the ILumb route. Methods: The IVent or Ilumb protocols each accured 5 groups of patients with cytology-confirmed LM from solid tumors. An injection of 15, 30, 60, 90 or 120 mCi of I-131 NaI was performed after thyroid blockade (Lugol solution and perchlorate), via an Ommaya reservoir (IVent) or lumbar puncture (ILumb). Patients underwent whole-body scintigraphy for biodistribution and radiation dosimetry. Follow-up studies consisted of serial CSF cytology, neuropsychology, ophthalmology, and serum tests (TSH and CBC) to 6 months. Results: The IVent and Ilumb studies accured 16 and 15 patients respectively with LM from melanoma, lung, breast and other tumors (13, 8, 6 and 4 of 31 patients). Because of re-entry into the protocols, one patient received a total of 407 mCi; the maximum radiation absorbed doses were estimated at 3716 cGy in the ventricular CSF and 54 cGy in the red marrow. No treatment-related NCI-Grade II/III/IV neurologic, hematologic or thyroid toxicity is noted. Transient improvements up to 6 weeks are noted in neuropsychologic tests (5/16 and 5/15), ophthalomologic test (3/16 and 1/15) and CSF cytology conversion (to negative) in 5/16 and 4/15 patients, respectively. Electrophysiology tests of 2 patients demonstrated normalization of P37 waves measured by somatosensory evoked potentials along with neuropsychologic test improvements. Conclusions: The MTD has not been reached up to 120 mCi on either the IVent or Ilumb protocol. Intrathecal I-131 NaI is likely to be efficacious to eradicate tumors in the CSF for LM therapy. Because of the low toxicity and likely efficacy, a phase II study with higher dosages is needed to fully explore therapeutic potentials of intrathecal I-131 NaI.

No significant financial relationships to disclose.

A phase I study of temozolomide (TMZ) and the farnesyltransferase inhibitor (FTI), lonafarnib (Sarazar, SCH66336) in recurrent glioblastoma

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Background: Farnesylation is essential for the post-translational modification of several proteins that play a role in cell proliferation and growth. FTIs demonstrate antiproliferative effects in a variety of tumor cell lines and xenograft models and enhanced efficacy by combining lonafarnib with TMZ compared with TMZ alone. Clinical studies show that dose-intense TMZ may have better efficacy then conventional dosing (Wick, Neurology 2004). Objective: Determine the maximum tolerated dose of lonafarnib when combined with a dose-intensified schedule of TMZ. Eligibility criteria: Histologically proven GBM; evidence of relaspe or progression; up to 2 prior chemotherapy regimens, prior TMZ permitted; KPS ≥ 60. No enzyme-inducing anticonvulsants. Methods: TMZ was given at 150 mg/m2 days 1–7 and 15–21; lonafarnib escalated by cohort: 100 mg BID, 150 mg BID, 200 mg BID on days 8–14 and 22–28 of a 28-day cycle. Response: Toxicity measured after cycle 1 using NCI CTCAE v3. Patient (pt)accrual used a 3 + 3 design. Response was evaluated q2 cycles. Standard response criteria (MacDonald) were used. Results: 15 patients were accrued. Median age 47 yrs; median KPS 90. M:F ratio was 11:4. No DLTs in any dose cohort, a pt (cohort 1) died day 29 of unrelated cardiac disease. 4 pts demonstrated partial response, all with prior TMZ failure, 3 pts showed prolonged stable disease. 6-month PFS rate estimated at 33%, median PFS 14 weeks. Treatment was well tolerated: 1 episode each of grade 3 diarrhea, esophagitis, fatigue and hypokalemia; 3 episodes of grade 3/4 leukopenia, 2 episodes of grade 3/4 neutropenia, and 2 episodes of grade 4 thrombocytopenia. Seven pts had grade 3/4 lymphopenia, some with persistant lymphopenia from prior TMZ. 1 pt had grade 4 pneumonitis of uncertain etiology. Conclusions: The alternating week schedule of TMZ/lonafarnib was well tolerated. Preliminary results suggest anti-tumor activity even in pts who had failed prior TMZ. It is not certain whether this activity is due to the dose-intensified TMZ or the treatment combination. Studies are planned to evaluate potential predictors of response (i.e MGMT gene promoter methylation) and expand the trial to obtain pharmacokinetic and additional efficacy data.

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Thalidomide: dermatological indications, mechanisms of action and side-effects

Thalidomide was first introduced in the 1950s as a sedative but was quickly removed from the market after it was linked to cases of severe birth defects. However, it has since made a remarkable comeback for the U.S. Food and Drug Administration-approved use in the treatment of erythema nodosum leprosum. Further, it has shown its effectiveness in unresponsive dermatological conditions such as actinic prurigo, adult Langerhans cell histiocytosis, aphthous stomatitis, Behçet's syndrome, graft-versus-host disease, cutaneous sarcoidosis, erythema multiforme, Jessner-Kanof lymphocytic infiltration of the skin, Kaposi sarcoma, lichen planus, lupus erythematosus, melanoma, prurigo nodularis, pyoderma gangrenosum and uraemic pruritus. This article reviews the history, pharmacology, mechanism of action, clinical uses and adverse effects of thalidomide.

Cobalt-Protoporphyrin treatment renders islets tolerant to interleukin-1 beta suppression

This study examined whether treating donor mice with a single dose of cobalt protoporphyrin (CoPP) induced heme oxygenase-1 (HO-1) and protected islet cells from interleukin-1 beta (IL-1 beta) suppression. Islets were isolated from mice receiving a single dose of either CoPP (20 mg/kg of body weight, CoPP islets) or isotonic NaCl solution vehicle (control islets), 24 hours before isolation. Glucose-stimulated insulin secretion (GSIS) and insulin content (IC) of the islets were determined following incubation in the presence versus absence of murine IL-1 beta for 21 or 65 hours. The HO-1 protein level of CoPP-induced islets, as determined by an enzyme immunoassay, was significantly higher than that of control islets at 12 hours (P <.01) and 30 hours (P <.05), and returned to basal levels at 56 hours (P = NS). Following a 21-hour incubation with IL-1 beta, CoPP islets secreted significantly more insulin upon glucose stimulation and preserved significantly more IC than control islets. After 65-hour incubation with IL-1 beta, CoPP islets secreted significantly less insulin upon glucose stimulation than control islets and preserved significantly less IC compared to islets incubated without IL-1 beta. In conclusion, treatment with cobalt-protoporphyrin to induce heme oxygenase-1 protects islets against the suppressive effects of IL-1 beta.

Cobalt-protoporphyrin treatment enhances murine isoislets engraftment

To study the effect of treatment with cobalt-protoporphyrin (CoPP) for the induction of the heme oxygenase-1 (HO-1) enzyme on islet engraftment donor mice received either a single intraperitoneal injection of CoPP (20 mg/kg body weight) 1 day prior to islet isolation or this injection plus a 9 day posttransplantation course of Copp. After a single injection of CoPP, the CoPP-induced islets contained higher HO-1 proteins than did the normal islets both at 12 (5.3 +/- 1.5 vs 0.1 +/- 0.1 ng/mg protein, P < .01) and at 30 hours (6.8 +/- 2.1 vs 0.4 +/- 0.3 ng/mg protein, P < .05), but not at 56 hours (1.9 +/- 0.8 vs 1.6 +/- 0.8 ng/mg protein, P > .05). In contrast, diabetic mice that received 75 CoPP-induced islets and a 9-day CoPP injection course posttransplantation showed better improvement in blood glucose levels and body weights than did the mice that only received CoPP-induced islets. Mice of both CoPP-treated groups displayed better improvement in glycemic control than mice that received control islets. At 8 weeks after transplantation, the insulin content of grafts from both CoPP groups was significantly higher than that in the control group. In conclusion, CoPP treatment for the induction of HO-1 enhances engraftment of islets in a syngeneic murine transplantation model.

Adenovirus hexon T-cell epitope is recognized by most adults and is restricted by HLA DP4, the most common class II allele

The immunogenicity of adenovirus (Ad) vectors is enhanced by virus-specific memory immune responses present in most individuals as a result of past exposure to these ubiquitous pathogens. We previously identified the first human T-cell epitope from the major capsid protein hexon, H910-924, and found that it is highly conserved among different Ad serotypes. Memory/effector T-cell responses to H910-924 were detected in 14 of 18 (78%) healthy adults by an interferon-gamma ELISPOT assay. Hexon peptide-specific CD4 T-cell lines were generated from three HLA-typed donors and analyzed using a panel of HLA homozygous B-cell lines and monoclonal antibodies to HLA class II loci. These studies reveal that the hexon epitope is restricted by HLA DP4, a class II allele present in 75% of the population. Analysis of overlapping peptides and peptides with single residue mutations identified a HLA DP4-binding motif. Additionally, antibodies to the hexon peptide were detected in all donor sera by dot blot assay and ELISA. Therefore, most individuals exhibit both memory B- and T-cell responses to this highly conserved epitope on hexon, an obligate component of all Ad vectors, including 'gutted' vectors. These data suggest that current strategies for the use of Ad gene therapy vectors will not evade memory immune responses to Ad.

Maintaining updated DNA-based HLA assignments in the National Marrow Donor Program Bone Marrow Registry

The National Marrow Donor Program (NMDP) has instituted an approach to address the impact of new alleles on the DNA-based HLA assignments obtained during volunteer donor typing. This approach was applied to the DRB typing results from 371,187 donors received from 14 laboratories in 1999. Samples were tested with a standardized set of sequence specific oligonucleotide reagents and the positive and negative hybridization results transmitted electronically to the NMDP. A software program interpreted the primary data into HLA assignments and rejected assignments which did not produce a result at the specified level of resolution. Comparison of the HLA assignments derived by the NMDP software to the assignments made by the laboratories using several local software prograins showed 90.5% of the assignments to be identical. Differences in assignments were explained by varying levels of typing resolution, variation in the inclusion of the second expressed DRB loci, disparity arising when alternative assignments were summarized, and failure to submit correct information. When the primary data collected in 1999 were interpreted into HLA assignments using the set of alleles defined in July 2000, 74% of the HLA-DRB assignments were altered by the description of new alleles, justifying the development of this software.

Transforming growth factor beta 1 dysregulation in a human oral carcinoma tumour progression model

A human oral tumour progression model was established that consists of normal epithelial cells and three cell lines representing stages from dysplastic to metastatic cells. To investigate the impact of exogenous transforming growth factor-beta 1 on this model system, we analysed the responsiveness of those cells to transforming growth factor-beta 1 and explored the potential mechanism underlying the transforming growth factor-beta 1 activity. We found that the growth of all cell types, regardless of their stage of tumour progression, is inhibited by transforming growth factor-beta 1, although to different degrees. Transforming growth factor-beta 1 induced the expression of cyclin-dependent kinase inhibitors p15(INK4B), p21WAF1/(CIP1) and p27(KIP1). In contrast, transforming growth factor-beta 1 was found to stimulate the invasive potential of one cell type that represents the most advanced stage of tumour phenotype, suggesting that the impact of transforming growth factor-beta 1 on functional features of tumour cells other than cellular proliferation may play a significant role in the process of oral tumour progression.

Becker's melanosis in a woman

Becker's melanosis is a relatively common, benign hamartoma, which is usually characterized by a hyperpigmented, hypertrichotic patch on the upper trunk or proximal upper extremities of males, with its onset during the peripubertal years. Commonly, there is an associated smooth muscle hamartoma on histology. We present a woman with a Becker's melanosis on the leg without hypertrichosis. We believe that the spectrum of Becker's nevus is greater than commonly thought and that cases similar to ours are not rare, but have been diagnosed as other conditions.

Chemopreventive effects of green tea polyphenols correlate with reversible induction of p57 expression

Green tea polyphenols are known to induce apoptosis in certain types of tumor cells. However, the mechanism(s) that enables normal cells to evade the apoptotic effect is still not understood. In this study, Western blot analysis combined with cycloheximide treatment was used to examine the effects of green tea polyphenols on the expression levels of p57, a cyclin-dependent kinase and apoptosis inhibitor, in normal human keratinocytes and in the oral carcinoma cell lines SCC25 and OSC2. The results showed that the most potent green tea polyphenol, (-)-epigallocatechin-3-gallate (EGCG), induced p57 in normal keratinocytes in a dosage- and time-dependent manner, while the levels of p57 protein in oral carcinoma cells were unaltered. The differential response in p57 induction was consistent with the apoptosis status detected by annexin V assay. The data suggest that the chemopreventive effects of green tea polyphenols may involve p57-mediated cell cycle regulation in normal epithelial cells.