Immune checkpoint inhibitors in advanced renal cell carcinoma: experience to date and future directions.

In recent years, there has been dramatic expansion of the treatment armamentarium for patients with advanced renal cell carcinoma (aRCC), including drugs targeting vascular endothelial growth factor and mammalian target of rapamycin (mTOR) pathways. Despite these advances, patient outcomes remain suboptimal, underscoring the need for therapeutic interventions with novel mechanisms of action. The advent of immunotherapy with checkpoint inhibitors has led to significant changes in the treatment landscape for several solid malignancies. Specifically, drugs targeting the programmed death 1 (PD-1) and cytotoxic T-lymphocyte associated antigen (CTLA-4) pathways have demonstrated considerable clinical efficacy and gained regulatory approval as single-agent or combination therapy for the treatment of patients with metastatic melanoma, non-small cell lung cancer, aRCC, advanced squamous cell carcinoma of the head and neck, urothelial cancer and Hodgkin lymphoma. In aRCC, the PD-1 inhibitor nivolumab was approved in both the United States and Europe for the treatment of patients who have received prior therapy, based on improved overall survival compared with the mTOR inhibitor everolimus. Other checkpoint inhibitors, including the CTLA-4 inhibitor ipilimumab in combination with several agents, and the PD-L1 inhibitor atezolizumab, are in various stages of clinical development in patients with aRCC. In this review, current evidence related to the clinical use of checkpoint inhibitors for the treatment of patients with aRCC is discussed, including information on the frequency and management of unconventional responses and the management of immune-related adverse events. In addition, perspectives on the future use of checkpoint inhibitors are discussed, including the potential value of treatment beyond progression, the potential use in earlier lines of care or in combination with other agents, and the identification of biomarkers to guide patient selection and enable individualization of therapy.

Multidisciplinary treatment of olfactory neuroblastoma: Patterns of failure and management of recurrence.

PURPOSE: Esthesioneuroblastoma is an uncommon malignancy of the head and neck for which there is no defined treatment protocol. The purpose of this study is to report our experience with the treatment and patterns of failure of this disease. METHODS AND MATERIALS: From 1994 to 2012, 37 previously unreported patients with esthesioneuroblastoma were evaluated, and 32 eventually treated for cure at 2 academic medical centers. All patients were staged with Kadish criteria. The mean and median follow-ups were 96.1 and 76.5 months respectively (range 6-240 months). RESULTS: The Kadish stage was A in 6 patients, B in 13 patients, and C in 13 patients. Four patients were initially treated with concurrent chemo-radiation therapy. Twenty-eight patients were treated with primary surgery. Two (2) underwent open medial maxillectomy and 26 underwent craniofacial resection (open - 17, endoscopic - 9). Three patients received curative surgical resection only. Seven patients failed either within the cranial axis or distantly, 6 of the 7 are dead of disease, 10-194 months following initial treatment. Six patients had isolated neck recurrences, 4/6 were salvaged with neck dissection and additional chemo-radiation and remain alive 30-194 months following initial treatment. Estimated overall survival rate at 10 years was 78% based on Kadish and T stages. CONCLUSION: In this retrospective analysis of 32 patients, Kadish stage C and stage T3/T4 tumors were associated with worse outcome. Total radiation dose of 60 Gy, margin status, patient age, were not found to have significant prognostic value.

Axitinib versus sorafenib in advanced renal cell carcinoma: subanalyses by prior therapy from a randomised phase III trial.

BACKGROUND: In the AXIS trial, axitinib prolonged progression-free survival (PFS) vs sorafenib in patients with advanced renal cell carcinoma (RCC) previously treated with sunitinib or cytokines. METHODS: In post hoc analyses, patients were grouped by objective response to prior therapy (yes vs no), prior therapy duration (< vs ⩾median), and tumour burden (baseline sum of the longest diameter < vs ⩾median). PFS and overall survival (OS), and safety by type and duration of prior therapy were evaluated. RESULTS: Response to prior therapy did not influence outcome with second-line axitinib or sorafenib. PFS was significantly longer in axitinib-treated patients who received longer prior cytokine treatment and sorafenib-treated patients with smaller tumour burden following sunitinib. Overall survival with the second-line therapy was longer in patients who received longer duration of prior therapy, although not significant in the sunitinib-to-axitinib sequence subgroup; OS was also longer in patients with smaller tumour burden, but not significant in the cytokine-to-axitinib sequence subgroup. Safety profiles differed modestly by type and duration of prior therapy. CONCLUSIONS: AXIS data suggest that longer duration of the first-line therapy generally yields better outcome with the second-line therapy and that lack of response to first-line therapy does not preclude positive clinical outcomes with a second-line vascular endothelial growth factor-targeted agent in patients with advanced RCC.

Mice deficient in Six5 develop cataracts: implications for myotonic dystrophy.

Expansion of a CTG trinucleotide repeat in the 3' UTR of the gene DMPK at the DM1 locus on chromosome 19 causes myotonic dystrophy, a dominantly inherited disease characterized by skeletal muscle dystrophy and myotonia, cataracts and cardiac conduction defects. Targeted deletion of Dm15, the mouse orthologue of human DMPK, produced mice with a mild myopathy and cardiac conduction abnormalities, but without other features of myotonic dystrophy, such as myotonia and cataracts. We, and others, have demonstrated that repeat expansion decreases expression of the adjacent gene SIX5 (refs 7,8), which encodes a homeodomain transcription factor. To determine whether SIX5 deficiency contributes to the myotonic dystrophy phenotype, we disrupted mouse Six5 by replacing the first exon with a beta-galactosidase reporter. Six5-mutant mice showed reporter expression in multiple tissues, including the developing lens. Homozygous mutant mice had no apparent abnormalities of skeletal muscle function, but developed lenticular opacities at a higher rate than controls. Our results suggest that SIX5 deficiency contributes to the cataract phenotype in myotonic dystrophy, and that myotonic dystrophy represents a multigenic disorder.

Fluorescein colchicine. Synthesis, purification, and biological activity.

The synthesis of a fluorescent colchicine derivative permits the localization of colchicine-binding receptors in cells. Fluorescein colchicine (FC) was prepared by the addition of fluorescein isothiocyanate to deacetyl colchicine. The product, FC, was separated from the reactants by thin-layer chromatography (TLC). The purity of FC was demonstrated by TLC, UV spectral analysis, and analysis of the kinetics of photodecomposition. FC inhibited [3H] colchicine binding to purified brain tubulin. The biological activity of FC was compared to the activity of unlabeled colchicine on mitosis, motility, secretion, and myogenesis. The effects of FC were identical to those of unlabeled colchicine in all biological systems tested. The results demonstrate that FC may be substituted for colchicine in biological experiments without significant loss in specificity or effectiveness.

Growth and transparency in the lens, an epithelial tissue, stimulated by pulses of PDGF.

The rat lens undergoes dramatic growth during early postnatal development. Lens weight increased by a factor of 23 in 26 days. Growth rate per day oscillated between 0 and 87 percent. A new culture system was designed to study the oscillations in growth during development. Lens growth and transparency in vitro required pulsatile delivery of platelet-derived growth factor (PDGF) in HL-1 serum-free medium. Continuous delivery of HL-1 medium with PDGF or pulsatile delivery of HL-1 medium without PDGF resulted in lens opacity and no growth. These results provide direct evidence that PDGF stimulates an epithelial tissue and that oscillations in growth occur during normal development of the rat lens.

Overall survival by clinical risk category for high dose interleukin-2 (HD IL-2) treated patients with metastatic renal cell cancer (mRCC): data from the PROCLAIMSM registry.

BACKGROUND: Prognostic scoring systems are used to estimate the risk of mortality from metastatic renal cell carcinoma (mRCC). Outcomes from different therapies may vary within each risk group. These survival algorithms have been applied to assess outcomes in patients receiving T-cell checkpoint inhibitory immunotherapy and tyrosine kinase inhibitor therapy, but have not been applied extensively to patients receiving high dose interleukin-2 (HD IL-2) immunotherapy. METHODS: Survival of 810 mRCC patients treated from 2006 to 2017 with high dose IL-2 (aldesleukin) and enrolled in the PROCLAIMSM registry data base was assessed utilizing the International Metastatic RCC Database Consortium (IMDC) risk criteria. Median follow-up is 23.4 months (mo.) (range 0.2-124 mo.). Subgroup evaluations were performed by separating patients by prior or no prior therapy, IL-2 alone, or therapy subsequent to IL-2. Some patients were in two groups. We will focus on the 356 patients who received IL-2 alone, and evaluate outcome by risk factor categories. RESULTS: Among the 810 patients, 721 were treatment-naïve (89%) and 59% were intermediate risk. Overall, of the 249 patients with favorable risk, the median overall survival (OS) is 63.3 mo. and the 2-year OS is 77.6%. Of 480 patients with intermediate risk, median OS is 42.4 mo., 2-year OS 68.2%, and of 81 patients with poor risk, median OS 14 mo., 2-year OS 40.4%. Among those who received IL-2 alone (356 patients), median OS is 64.5, 57.6, and 14 months for favorable, intermediate and poor risk categories respectively. Two year survival among those treated only with HD IL-2 is 73.4, 63.7 and 39.8%, for favorable, intermediate and poor risk categories respectively. CONCLUSIONS: Among mRCC patients treated with HD IL-2, all risk groups have median and 2-year survival consistent with recent reports of checkpoint or targeted therapies for mRCC. Favorable and intermediate risk (by IMDC) patients treated with HD IL-2 have longer OS compared with poor risk patients, with most durable OS observed in favorable risk patients. Favorable risk patients treated with HD IL-2 alone have a 2-year OS of 74%. These data continue to support a recommendation for HD IL-2 for patients with mRCC who meet eligibility criteria. TRIAL REGISTRATION: PROCLAIM, NCT01415167 was registered with ClinicalTrials.gov on August 11, 2011, and initiated for retrospective data collection until 2006, and prospective data collection ongoing since 2011.

Small heat-shock proteins and their potential role in human disease.

The elevated expression of stress proteins is considered to be a universal response to adverse conditions, representing a potential mechanism of cellular defense against disease and a potential target for novel therapeutics, including gene therapy and chaperone-modulating reagents. Recently, a single mutation in the small heat-shock protein human alphaB-crystallin was linked to desmin-related myopathy, which is characterized by abnormal intracellular aggregates of intermediate filaments in human muscle. New findings demonstrate that the high level of expression of stress proteins can contribute to an autoimmune response and can protect proteins that contribute to disease processes.

Phase I trial of 2B1, a bispecific monoclonal antibody targeting c-erbB-2 and Fc gamma RIII.

2B1 is a bispecific murine monoclonal antibody (BsMAb) with specificity for the c-erbB-2 and Fc gamma RIII extracellular domains. This BsMAb promotes the targeted lysis of malignant cells overexpressing the c-erbB-2 gene product of the HER2/neu proto-oncogene by human natural killer cells and mononuclear phagocytes expressing the Fc gamma RIII A isoform. In a Phase I clinical trial of 2B1, 15 patients with c-erbB-2-overexpressing tumors were treated with 1 h i.v. infusions of 2B1 on days 1, 4, 5, 6, 7, and 8 of a single course of treatment. Three patients were treated with daily doses of 1.0 mg/m2, while six patients each were treated with 2.5 mg/m2 and 5.0 mg/m2, respectively. The principal non-dose-limiting transient toxicities were fevers, rigors, nausea, vomiting, and leukopenia. Thrombocytopenia was dose limiting at the 5.0 mg/m2 dose level in two patients who had received extensive prior myelosuppressive chemotherapy. Murine antibody was detectable in serum following 2B1 administration, and its bispecific binding properties were retained. The pharmacokinetics of this murine antibody were variable and best described by nonlinear kinetics with an average t 1/2 of 20 h. Murine antibody bound extensively to all neutrophils and to a proportion of monocytes and lymphocytes. The initial 2B1 treatment induced more than 100-fold increases in circulating levels of tumor necrosis factor-alpha, interleukin 6, and interleukin 8 and lesser rises in granulocyte-monocyte colony-stimulating factor and IFN-gamma. Brisk human anti-mouse antibody responses were induced in 14 of 15 patients. Several minor clinical responses were observed, with reductions in the thickness of chest wall disease in one patient with disseminated breast cancer. Resolution of pleural effusions and ascites, respectively, were noted in two patients with metastatic colon cancer, and one of two liver metastases resolved in a patient with metastatic colon cancer. Treatment with 2B1 BsMAb has potent immunological consequences. The maximum tolerated dose and Phase II daily dose for patients with extensive prior myelosuppressive chemotherapy was 2.5 mg/m2. Continued dose escalation is required to identify the maximally tolerated dose for patients who have been less heavily pretreated.

Binding characteristics and antitumor properties of 1A10 bispecific antibody recognizing gp40 and human transferrin receptor.

The bispecific murine monoclonal antibody (MAb) 1A10 has specificity for the human transferrin receptor (TfR) and the human tumor-associated antigen gp40. This antibody, therefore, functions as an "antigen fork" by binding to two distinct antigens on the same malignant cell. Highly purified 1A10 inhibits the growth of cells coexpressing high levels of human TfR and the tumor-associated antigen gp40 by binding to both target antigens. In SW948 cells, the majority of 1A10 binding is via its gp40 specificity, and half-maximal inhibition of cell growth by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay requires 20-30-micrograms/ml concentrations of 1A10. The binding of 1A10 correlates with growth inhibition in the cell lines HT-29, SK-OV-3, OVCAR-2, and OVCAR-3. The growth of OVCAR-10 cells, which express little gp40 and TfR, is not inhibited by 1A10. However, SK-BR-3 cells, which express abundant gp40 and extremely high levels of TfR, are insensitive to the effects of 1A10. In some cell lines, combined exposure to 1A10 and the iron chelator deferoxamine mesylate has synergistic antiproliferative effects. A single i.p. dose of 600 micrograms 1A10 is sufficient to achieve an estimated tumor concentration of at least 30 micrograms/ml for 7 days in C.B17/Icr-scid mice bearing SW948 human tumor xenografts. Treatment of scid mice bearing day 2 or day 4 SW948 xenografts with single or multiple 1A10 doses inhibits tumor growth in a dose-related fashion. Antitumor effects are not seen with therapy using either parental antibody of 1A10. The antiproliferative properties of 1A10 in tumor cells overexpressing gp40 and TfR suggest avenues for the development of new bispecific antibody-promoted treatment strategies.

Outpatient biochemotherapy with interleukin-2 and interferon alfa-2b in patients with metastatic malignant melanoma: results of two phase II cytokine working group trials.

PURPOSE: The Cytokine Working Group performed a randomized phase II trial of two outpatient biochemotherapy regimens to identify an outpatient regimen with high antitumor activity and less toxicity than inpatient regimens which might be compared with chemotherapy or inpatient biochemotherapy regimens in future phase III trials. PATIENTS AND METHODS: Eighty-one patients with metastatic malignant melanoma received dacarbazine 250 mg/m(2)/d intravenously (IV) and cisplatin 25 mg/m(2)/d IV on days 1, 2, and 3, plus interferon (IFN) alfa-2b 5 mU/m(2) subcutaneously (SC) on days 6, 8, 10, 13, and 15, given every 28 days. Interleukin-2 (IL-2) was given daily on days 6 to 10 and 13 to 15. In group 1, IV IL-2 was given at 18.0 MU/m(2), and in group 2, SC IL-2 was given at 5.0 mU/m(2). RESULTS: In group 1 (IV IL-2), there were five complete responses (CRs) and 11 partial responses (PRs) among 44 patients (objective response rate [ORR], 36%; 95% confidence interval [CI], 22% to 51%). In group 2 (SC IL-2), there was one CR and five PRs among the 36 patients (ORR, 17%; 95% CI, 4% to 29%). The median survival was 10.7 months in group 1 and 7.3 months in group 2. Eleven patients in group 1 and four patients in group 2 remain alive as of the last follow-up. Toxicities in both groups were similar. No patient required hospitalization for neutropenic fever. CONCLUSION: Biochemotherapy has activity in these outpatient regimens with acceptable toxicity. The antitumor activity observed with the IV IL-2 regimen seems similar to that of inpatient biochemotherapy regimens. If inpatient biochemotherapy regimens develop an established role in the management of melanoma, future phase III trial comparisons with this outpatient IV IL-2 regimen would be appropriate.

Lens cytoplasmic phase separation.

Cytoplasmic transparency is a unique feature of lens cells. The cytoplasm is a concentrated solution of crystallin proteins with minor constituents that include cytoskeletal proteins and lens specific intermediate filaments. Under normal physiological conditions, the proteins exist as a single transparent phase. With normal aging, progressive modification of the interactions between lens proteins occurs so that conditions within the lens become favorable for phase separation. These conditions produce intracellular inhomogeneities that approach or exceed the dimensions of the wavelength of visible light (400 to 700 nm) and light scattering from lens cells increases. The resulting opacification is the primary factor in the visual loss experienced in cataract, the leading cause of blindness in the world. We study biochemical factors that regulate the cytoplasmic phase separation and maintain normal cellular transparency.

Site-directed mutations within the core "alpha-crystallin" domain of the small heat-shock protein, human alphaB-crystallin, decrease molecular chaperone functions.

Site-directed mutagenesis was used to evaluate the effects on structure and function of selected substitutions within and N-terminal to the core "alpha-crystallin" domain of the small heat-shock protein (sHsp) and molecular chaperone, human alphaB-crystallin. Five alphaB-crystallin mutants containing single amino acid substitutions within the core alpha-crystallin domain displayed a modest decrease in chaperone activity in aggregation assays in vitro and in protecting cell viability of E. coli at 50 degrees C in vivo. In contrast, seven alphaB-crystallin mutants containing substitutions N-terminal to the core alpha-crystallin domain generally resembled wild-type alphaB-crystallin in chaperone activity in vitro and in vivo. Size-exclusion chromatography, ultraviolet circular dichroism spectroscopy and limited proteolysis were used to evaluate potential structural changes in the 12 alphaB-crystallin mutants. The secondary, tertiary and quaternary structures of mutants within and N-terminal to the core alpha-crystallin domain were similar to wild-type alphaB-crystallin. SDS-PAGE patterns of chymotryptic digestion were also similar in the mutant and wild-type proteins, indicating that the mutations did not introduce structural modifications that altered the exposure of proteolytic cleavage sites in alphaB-crystallin. On the basis of the similarities between the sequences of human alphaB-crystallin and the sHsp Mj HSP16.5, the only sHsp for which there exists high resolution structural information, a three-dimensional model for alphaB-crystallin was constructed. The mutations at sites within the core alpha-crystallin domain of alphaB-crystallin identify regions that may be important for the molecular chaperone functions of sHsps.

Theoretical and experimental basis for the inhibition of cataract.

Aggregation of the lens proteins to form high molecular weight clusters is a major contributing factor in age-onset nuclear cataract [Benedek, G. B. (1971) Theory of transparency of the eye. Appl. Optics, 10, 459-473]. This aggregation occurs continually throughout life and contributes to an exponential increase, as a function of age, in the intensity of the light backscattered out of the lens. The time constant deltaT for this exponential increase in human populations is a valuable index, helpful for conducting clinical trials. In-vitro studies have identified reagents capable of inhibiting high molecular weight aggregate formation, as well as the non-covalent interprotein interactions responsible for phase separation. These reagents are also found experimentally to be effective cataract inhibitors in animal model systems in vivo. We believe that the stage is now set for human clinical trials of putative cataract inhibitors. We present rough quantitative estimates of the trial parameters needed to assure an unambiguous determination of efficacy in a trial population. Such a trial simply requires a measurement of the time constant deltaT in the treated population relative to the untreated population. A successful outcome of the trial is indicated if deltaT increases by 20% over that found for the untreated population. Our estimates suggest efficacy could be determined in a two year trial involving about 300 subjects in the treated group.

Dendritic cells transduced with full-length wild-type p53 generate antitumor cytotoxic T lymphocytes from peripheral blood of cancer patients.

Accumulation of wild-type or mutant p53 protein occurs in approximately 50% of human malignancies. This overexpression may generate antigenic epitopes recognized by CTLs. Because normal cells have undetectable levels of p53, these CTLs are likely to be tumor specific. Here, for the first time, we test the hypothesis that full-length wild-type p53 protein can be used for generation of an immune response against tumor cells with p53 overexpression. T cells obtained from nine HLA-A2-positive cancer patients and three HLA-A2-positive healthy individuals were stimulated twice with dendritic cells (DCs) transduced with an adenovirus wild-type p53 (Ad-p53) construct. Significant cytotoxicity was detected against HLA-A2-positive tumor cells with accumulation of mutant or wild-type p53 but not against HLA-A2-positive tumor cells with normal (undetectable) levels of p53 or against HLA-A2-negative tumor cells. This response was specific and mediated by CD8+ CTLs. These CTLs recognized HLA-A2-positive tumor cells expressing normal levels of p53 protein after their transduction with Ad-p53 but not with control adenovirus. Stimulation of T cells with Ad-p53-transduced DCs resulted in generation of CTLs specific for p53-derived peptide. These data demonstrate that DCs transduced with the wild-type p53 gene were able to induce a specific antitumor immune response. This offers a new promising approach to immunotherapy of cancer.

Daily subcutaneous ultra-low-dose interleukin 2 with daily low-dose interferon-alpha in patients with advanced renal cell carcinoma.

A limited institution Phase II pilot study was performed using a very low-dose combination of daily s.c. interleukin (IL)-2 with IFN-alpha-2b in patients with advanced renal cancer in an attempt to duplicate or increase the response documented with higher dose schedules without the attendant toxicity profile. We selected a dose of IL-2 with documented immunological activity and combined it with clinically active low-dose IFN. Between August 1994 and September 1996, 19 patients with metastatic renal cell carcinoma, who had been judged incapable of tolerating high-dose i.v. IL-2, were treated with IL-2 (1 million units/m2/day) and IFN (1 million units/day), administered s.c. daily. All treatments were administered on an outpatient basis. Virtually all patients had bulky tumor burden with multiple sites of involvement, including five patients with bone metastases. No major objective responses were observed; however, one patient experienced a minor response lasting 13 months, with an associated improvement in performance status. Median survival was 6 months, and 1-year survival was 16%. Toxicity was generally mild and consisted almost entirely of constitutional symptoms. No serious grade 3 or 4 toxicity was observed, although two patients withdrew from treatment due to treatment-related fatigue. On therapy, mild eosinophilia but no lymphocytosis was noted; in fact, peripheral lymphocyte counts decreased, only to rebound after treatment was discontinued. No toxic deaths occurred. Despite the reasonable tolerability of this daily low-dose s.c. regimen, we conclude that this regimen is an ineffective treatment in metastatic renal cell carcinoma patients who are incapable of tolerating high-dose i.v. IL-2.

Clinical significance of defective dendritic cell differentiation in cancer.

Defective dendritic cell (DC) function has been described previously in cancer patients and tumor-bearing mice. It can be an important factor in the escape of tumors from immune system control. However, the mechanism and clinical significance of this phenomenon remain unclear. Here, 93 patients with breast, head and neck, and lung cancer were investigated. The function of peripheral blood and tumor draining lymph node DCs was equally impaired in cancer patients, consistent with a systemic rather than a local effect of tumor on DCs. The number of DCs was dramatically reduced in the peripheral blood of cancer patients. This decrease was associated with the accumulation of cells lacking markers of mature hematopoietic cells. The presence of these immature cells was closely associated with the stage and duration of the disease. Surgical removal of tumor resulted in partial reversal of the observed effects. The presence of immature cells in the peripheral blood of cancer patients was closely associated with an increased plasma level of vascular endothelial growth factor but not interleukin 6, granulocyte macrophage colony-stimulating factor, macrophage colony-stimulating factor, interleukin 10, or transforming growth factor-beta and was decreased in lung cancer patients receiving therapy with antivascular endothelial growth factor antibodies. These data indicate that defective DC function in cancer patients is the result of decreased numbers of competent DCs and the accumulation of immature cells. This effect may have significant clinical implications.

Radioprotection against cataract formation by WR-77913 in gamma-irradiated rats.

Protection by WR-77913 against radiation-induced cataract formation in rats was observed following intraperitoneal (i.p.) administration of drug (1160 mg/kg) 15-30 min before exposure to 15.3 Gy of Cs-137 whole head irradiation. Control groups included irradiated, non-protected animals, and sham-irradiated aging controls. Protection was documented photographically and by analysis of eye lens constituents. All non-protected irradiated animals developed dense cataracts throughout the lens between 90-120 days post-irradiation, while WR-77913 protected animals developed minimal lens opacification through 200 days post-irradiation. No opacification in aging controls was seen. Lens protein analysis by Lowry assay and size exclusion HPLC showed radioprotected and aging control animals were similar in protein content, distribution of total and soluble protein, and degree of lens hydration. This contrasted significantly with cataractous lenses of non-protected animals. In cataractous lenses, the soluble protein concentration in the 25-43 K dalton range was approximately 10% of that found in radioprotected or aging control lenses. Hydration was substantially higher in cataractous lens. These results indicate that WR-77913 protects against lens opacification, protein insolubilization, and hydration in lenses of irradiated animals. Biodistribution studies with [S-35]-WR-77913 showed ocular uptake of drug within 15 minutes after i.p. injection, which remained relatively constant through 60 min. The relative order of drug concentration for individual eye components was: globe greater than total eye approximately equal to humor greater than lens. Although the mechanism of radioprotection observed remains to be elucidated, WR-77913 clearly prevents radiation-induced cataracts in rats. The potentially significant clinical use for this radioprotective compound is being investigated further.

Metanephric adenosarcoma in a young adult: morphologic, immunophenotypic, ultrastructural, and fluorescence in situ hybridization analyses: a case report and review of the literature.

Metanephric neoplasms are uncommon renal tumors that arise in both children and adults. They may be composed of small epithelial cells or benign stroma, or both, and are termed metanephric adenoma, metanephric stromal tumor, or metanephric adenofibroma, respectively. Thus far, these tumors have been known for their benign behavior. We present the case of a 21-year-old woman who developed a neoplasm composed of a renal epithelial component identical to metanephric adenoma combined with a malignant spindle cell sarcoma. The epithelial component was positive for pankeratin AE1/3, whereas the sarcomatous component was negative for epithelial markers and positive for vimentin, CD34, and CD117. No smooth muscle differentiation was apparent in the sarcoma by immunohistochemistry or ultrastructural analysis. By fluorescent in situ hybridization analysis of the sarcomatous component there was monosomy of the X chromosome, but no apparent variation from the normal diploid pattern for chromosomes 3, 7, 12, and 17. We conclude that the spectrum of metanephric neoplasia should be expanded to include malignant stromal variants, and we propose the term "metanephric adenosarcoma" for the present case.

Inhibition of lens opacification during the early stages of cataract formation.

PURPOSE: To characterize the time period during cataract formation in which administration of pantethine inhibits lens cell opacification in the selenite model for cataract. METHODS: Pantethine was administered to neonatal rat pups at selected time points from -0.5 to 17 hours with respect to injection of selenite at time = 0. The injection dose of pantethine was 820 mg/kg (1.5 mmol/kg) diluted in water at 410 mg/ml concentration. The injection dose of selenite was 3.28 mg/kg (19 mumol/kg) diluted in saline at 1.8 mg/ml concentration. Opacification was observed using a slit lamp microscope at selected time points over a 14-day period. Cataracts were staged using a classification of opacity from 0 (normal) to 6 (mature). RESULTS: The effect of pantethine was characterized by three different time periods: administration -0.5 to 6 hours with respect to selenite injection provided highly significant protection, P < 0.001; administration 8 hours after selenite provided significant protection, P < 0.005; administration 10 to 17 hours after selenite was not protective. CONCLUSIONS: The metabolite pantethine inhibited lens opacification during cataract formation in the selenite model. Even when pantethine was injected several hours after the administration of selenite, opacification was inhibited. Advanced stages of opacification were unresponsive to the administration of pantethine. The inhibitory effect of pantethine was statistically significant when administered during the earliest stage of opacification in the selenite model for cataract.