Legumain affects the PI3K/AKT tumor progression pathway in retinoblastoma.

Known as a common malignant tumor among children, retinoblastoma (RB) is highly malignant and has poor prognosis, damages children's vision and degrades quality of life. To identify a potential molecular mechanism of RB, we conducted this study on legumain (LGMN), which is highly expressed in multiple tumors. In this study, we found that LGMN was significantly upregulated in RB cells and was positively expressed in RB tissues. We confirmed that LGMN overexpression (LGMN-OE) can promote RB cell proliferation and inhibit cell apoptosis through CCK8 experiments and flow cytometry. In addition, real-time quantitative polymerase chain reaction (RT‒qPCR) and Western blot results showed that LGMN-OE could regulate the expression of epithelial-mesenchymal transformation-related genes and proteins, related to tumor invasion and metastasis. Moreover, after LGMN knock down, the result was the opposite., RNA sequence analysis revealed 1159 differentially expressed genes between LGMN-OE and the negative control (NCOE), of which 564 were upregulated and 595 were downregulated. The first 10 genes were verified by RT‒qPCR based on P value and fold change. Interestingly, we found that LGMN could regulate the expression of recoverin (RCVRN)through a gene responsible for cancer-related retinopathy. We also screened and verified that LGMN partially activated the PI3K/AKT pathway in RB. Furthermore, we evaluated the effect of legumain inhibitors (e.g., esomeprazole) on RB, and the results suggest that esomeprazole may provide a reference for the clinical adjuvant treatment of RB. In conclusion, legumain can serve as an attractive target for RB therapy and hopefully provide new insights and ideas for the development of targeted drugs and precise personalized clinical therapy.

Prospective phase II study of children affected by bilateral intraocular retinoblastoma with macular involvement of both eyes or in the only preserved eye. Macular tumor control, eye preservation rate, and visual outcome.

BACKGROUND: Conservative treatments of intraocular retinoblastoma often consist of chemotherapy and focal treatments. The protocols vary and currently may combine two or three drugs, with different number of cycles, associated to the ocular treatments. In case of macular/paramacular involvement, tumor location and retinal scars induced by focal treatments often have a major negative impact on final visual outcome. METHODS: This study aimed to include children affected by bilateral intraocular macular/paramacular retinoblastoma in a prospective phase II study. The protocol consisted of six cycles of a three-drug combination (vincristine, etoposide, carboplatin), and the addition of macula-sparing transpupillary thermotherapy (TTT) to the third cycle. The primary endpoint was the local control rate without external beam radiotherapy (EBR) and/or enucleation. RESULTS: Nineteen patients (26 eyes) were included from July 2004 to November 2009. Thirteen eyes belonged to group V of the Reese-Ellsworth classification and 10 to group D of the International Intraocular Retinoblastoma Classification. Macular/paramacular tumors were treated with chemotherapy alone in nine eyes, and with chemotherapy associated with macula-sparing TTT in 17 eyes. Four eyes experienced macular relapse. At a median follow up of 77 months, 23 eyes (88.5%) were saved without EBR, two were enucleated and one received EBR. The median visual acuity of the 24 saved eyes was 20/50. No severe adverse effect was observed. CONCLUSION: Six cycles of a three-drug combination associated with macula-sparing TTT achieved good tumor control, improved eye preservation rates without EBR, and decreased macular damage, often providing satisfactory visual results with long-term follow up.

Effectively suppressed angiogenesis-mediated retinoblastoma growth using celastrol nanomicelles.

Celastrol, a Chinese herbal medicine, has already shown an inhibition effect on retinoblastoma growth activity in our previous research, but its mechanism is not well understood. Angiogenesis is a main driving force in many tumors. Here, we studied whether celastrol could inhibit angiogenesis-mediated retinoblastoma growth, if so, through what mechanism. In this work, we developed celastrol-loaded polymeric nanomicelles to improve the poor water solubility of celastrol. When given an intraperitoneal injection to mice bearing human retinoblastoma xenografts, celastrol nanomicelles (CNMs, 27.2 mg/kg/2 days) significantly reduced the weight and the volume of tumors and decreased tumor angiogenesis. We found that CNMs suppressed hypoxia-induced proliferation, migration, and invasion by human umbilical vascular endothelial cells (EA.hy 926) in a dose-dependent manner. Furthermore, CNMs inhibited SO-Rb 50 cells-induced sprouting of the vessels and vascular formation in chick embryo chorioallantoic membrane assay in vitro. To understand the molecular mechanism of these activities, we assessed the signaling pathways in CoCl2 treated EA.hy 926. CNMs inhibited the hypoxia-induced HIF-1α and VEGF. In conclusion, our results reveal that CNMs target the HIF-1α/VEGF pathway, which may be an important reason for the suppression of retinoblastoma growth and angiogenesis.

Tetramethylpyrazine downregulates transcription of the CXC receptor 4 (CXCR4) via nuclear respiratory factor­1 (Nrf­1) in WERI­Rb1 retinoblastoma cells.

Tetramethylpyrazine (TMP; an extract of the Chinese herbal medicine, Chuanxiong) has been shown to exert remarkable antiretinoblastoma (RB) effects. Based on our previous study, the target gene was found to be C­X­C chemokine receptor type 4 (CXCR4). CXCR4 is a prognostic marker in various types of cancer, but the exact mechanisms underlying the regulation of CXCR4 expression by TMP in WERI­Rb1 cells have yet to be fully elucidated. In the present study, it was revealed that TMP significantly downregulated CXCR4 expression and inhibited CXCR4 promoter activity in WERI­Rb1 cells, indicating that TMP inhibits CXCR4 expression in WERI­Rb1 cells through transcriptional regulatory mechanisms. Among the numerous transcription factors involved in CXCR4 function, including Yin Yang 1 (YY1), nuclear respiratory factor­1 (Nrf­1), Krüppel­like Factor 2 (KLF2), specificity protein 1 (SP1), and nuclear factor­κB subunit 1 (NF­κB1), only TMP led to a significant downregulation of Nrf­1 expression. Chromatin immunoprecipitation assays further indicated that Nrf­1 directly binds to the promoter region of CXCR4, and silencing Nrf­1 via siRNA transfection notably inhibited CXCR4 expression in WERI­Rb1 cells. In addition, the expression levels of both Nrf­1 and CXCR4 increased concomitantly with WERI­Rb1 cell density. Furthermore, the downregulation of Nrf­1 and CXCR4 expression in RB by TMP was confirmed in vivo. Taken together, the results of the present study have uncovered a novel mechanism in which CXCR4 expression is regulated by Nrf­1 in WERI­Rb1 cells, thereby identifying novel potential targets for the treatment of RB, and providing evidence for the clinical application of TMP in adjuvant retinoblastoma therapy.

Conservative treatment of retinoblastoma: a prospective phase II randomized trial of neoadjuvant chemotherapy followed by local treatments and chemothermotherapy.

PurposeIntraocular retinoblastoma treatments often combine chemotherapy and focal treatments. A first prospective protocol of conservative treatments in our institution showed the efficacy of the use of two courses of chemoreduction with etoposide and carboplatin, followed by chemothermotherapy using carboplatin as a single agent and diode laser. In order to decrease the possible long-term toxicity of chemotherapy due to etoposide, a randomized neoadjuvant phase II protocol was conducted using vincristine-carboplatin vs etoposide-carboplatin.Patients and methodsThe study was proposed when initial tumor characteristics did not allow front-line local treatments. Patients included in this phase II noncomparative randomized study of neoadjuvant chemotherapy received vincristin-carboplatin (new arm) vs etoposide-carboplatin (our reference arm). They were subsequently treated by local treatments and chemothermotherapy. Primary end point was the need for secondary enucleation or external beam radiotherapy (EBRT) not exceeding 40% at 2 years.ResultsA total of 65 eyes in 55 children were included in the study (May 2004 to August 2009). Of these, 32 eyes (27 children) were treated in the arm etoposide-carboplatin and 33 eyes (28 children) in the arm vincristin-carboplatin. At 2 years after treatment, 23/33 (69.7%) eyes were treated and salvaged without EBRT or enucleation in the arm vincristin-carboplatin and 26/32 (81.2%) in the arm etoposide-carboplatin.ConclusionEven if the two treatment arms could be considered as sufficiently active according to the study decision rules, neoadjuvant chemotherapy by two cycles of vincristine-carboplatin followed by chemothermotherapy appear to offer less optimal local control than the etoposide-carboplatin combination.

Indocyanine Green-Enhanced Transpupillary Thermotherapy for Retinoblastoma: Analysis of 42 Tumors.

PURPOSE: To evaluate the efficacy of indocyanine green-enhanced transpupillary thermotherapy (ICG-TTT) for retinoblastoma that shows suboptimal response to conventional treatments. METHODS: A single center, retrospective chart review. The technique involved ICG infusion (range: 0.3 to 0.5 mg/kg) 1 minute prior to applying TTT using the indirect ophthalmoscope technique with a spot size of 1.2 mm. RESULTS: There were 42 retinoblastomas in 30 eyes of 21 patients treated with ICG-TTT. The reasons for ICG enhancement included suboptimal response to standard TTT (n = 31, 74%), recurrence after standard TTT (n = 3, 7%), or minimally pigmented fundus with poor standard TTT uptake (n = 8, 19%). The mean patient age at treatment was 12 months (median: 11.6 months, range: 3 to 31 months). The mean tumor base was 3.5 mm (median: 3 mm), mean tumor thickness was 2.5 mm (median; 2 mm), mean distance to the foveola was 2.6 mm (median: 3 mm), and mean distance to the optic disc was 2.2 mm (median: 0.75 mm). Treatment parameters included a spot size of 1.2 mm, mean power of 760 mW (median: 800 mW, range: 400 to 1,200 mW), and mean duration of 4 minutes (median: 4 minutes, range: 0.5 to 14 minutes). Following a median of 2 sessions (range: 1 to 5 sessions) of ICG-TTT, 33 (79%) tumors demonstrated complete regression. The mean tumor thickness postoperatively was 1.7 mm. Two (5%) tumors showed minimal regression after ICG-TTT. During a mean follow-up of 46 months (median: 33 months), tumor recurrence after ICG-TTT developed in 7 (17%) cases at a mean interval of 7 months. Local complications of ICG-TTT included focal paraxial cataract (n = 2, 7%), iris atrophy (n = 1, 3%), and transient retinal hemorrhage (n = 2, 7%). Systemic problems included ICG allergy (n = 1, 5%). Overall, tumor control and globe salvage was achieved in all 30 (100%) eyes. There were no metastatic events. CONCLUSIONS: ICG-TTT is an effective alternative for reti-noblastoma control, particularly for small tumors that show suboptimal response to standard

[Available approaches to retinoblastoma therapy--literature review]. / Dostepne metody leczenia siatkówczaka--przeglad pismiennictwa.

Retinoblastoma is a malignant tumor and treatment should be started as soon as possible. Currently, the most common approach combines local therapy with chemotherapy. Chemoreduction represents a significant advance in the treatment of retinoblastoma. This paper presents treatment approaches including local chemotherapy, intraarterial and intravitreous chemiotheraphy. retinoblastoma, chemotherapy chemoreduction, brachytherapy, thermotherapy, laser photocoagulation, proton radiotherapy, teleradiotherapy, intraarterial chemotherapy.

Treatment of retinoblastoma: The Institut Curie experience on a series of 730 patients (1995 to 2009).

INTRODUCTION: To describe the results of retinoblastoma treatment from 1995-2009 in a single institution. MATERIAL AND METHODS: Retrospective review of the charts of patients treated for retinoblastoma. Clinical characteristics at diagnosis, treatments and outcomes in terms of survival and ocular preservation are described. RESULTS: During the study period 826 children were referred for retinoblastoma and 730 were managed in our institution. Four hundred and eleven children presented with unilateral retinoblastoma and 319 with bilateral retinoblastoma. Median follow-up is of 93 months. Global survival is 98.5% of children, 10 children presented with second tumors, 11 children died (6 of tumor-related causes). Of the 411 children with unilateral retinoblastoma enucleation was needed at diagnosis for 324 (78.8%). Conservative treatments were attempted for 87 patients (21.2%) and ocular preservation obtained for 65 patients (74% of eyes). Three hundred and nineteen patients presented with bilateral retinoblastoma. Three hundred and ten could be treated conservatively for at least one eye. Initial intravenous chemotherapy was necessary for 75% of them. Ocular preservation without external beam radiation was possible for 221 patients (70%). The use of EBR decreased significantly after 2004 (9.1% of eyes vs 25.1%: P<0.001). DISCUSSION: Management and treatment of retinoblastoma are complex, adapted to the extent of the disease. Survival is good. Enucleation is still required for extensive ocular disease, especially for unilateral patients. Intravenous chemotherapy allows good tumor control and eye preservation and decrease the need of EBR. CONCLUSIONS: Retinoblastoma treatment with intravenous chemotherapy and ocular adjuvant therapies is very effective on the local tumor control and eye preservation.

Synergistic Effect of Curcumin in Combination with Anticancer Agents in Human Retinoblastoma Cancer Cell Lines.

PURPOSE: Curcumin (diferuloylmethane), a phenolic compound obtained from the rhizome of the herb Curcuma longa, is known to have anti-proliferative and anti-tumor properties. In this study, we evaluated the cytotoxic effect of curcumin alone and in combination with individual drugs like carboplatin, etoposide, or vincristine in a human retinoblastoma (RB) cancer cell line. MATERIALS AND METHODS: A drug-drug interaction was analyzed using the median effect/isobologram method and combination index values were used to characterize the interaction as synergistic or additive. We also performed the apoptosis and cell-cycle kinetics study with single drugs in combination with curcumin in a human RB cell lines (Y79 and Weri-Rb1). RESULTS: Curcumin caused concentration-dependent decrease in cell proliferation, cell kinetics, and also induced apoptosis in both the RB cell lines. When combination of curcumin with individual drugs like carboplatin or etoposide or vincristine was treated on to RB cells, both cell viability and cell cycling were reduced and increased apoptosis was noted, in comparison with single drug treatment. These effects were significant in both the cell lines, indicating the ability of curcumin to increase the sensitivity of RB cells to chemotherapy drugs. CONCLUSION: Our in vitro findings showed that the combination of curcumin with single drug treatment showed marked synergistic inhibitory effect against RB cell lines. These results suggest that curcumin can be used as a modulator which may have a potential therapeutic value for the treatment of RB cancer patients.

BAG3 protects against hyperthermic stress by modulating NF-κB and ERK activities in human retinoblastoma cells.

PURPOSE: BCL2-associated athanogene 3 (BAG3), a co-chaperone of HSP70, is a cytoprotective and anti-apoptotic protein that acts against various stresses, including heat stress. Here, we examined the effect of BAG3 on the sensitivity of human retinoblastoma cells to hyperthermia (HT). METHODS: We examined the effects of BAG3 knockdown on the sensitivity of Y79 and WERI-Rb-1cells to HT (44 °C, 1 h) by evaluating apoptosis and cell proliferation using western blotting, real-time quantitative PCR (qPCR), flow cytometry, and a WST-8 assay kit. Furthermore, we examined the effects of activating nuclear factor-kappa B (NF-κB) and extracellular signal-regulated kinase (ERK) using western blotting and real time qPCR. RESULTS: HT induced considerable apoptosis along with the activation of caspase-3 and chromatin condensation. The sensitivity of Y79 and WERI-Rb-1 cells to HT was significantly enhanced by BAG3 knockdown. Compared to HT alone, the combination of BAG3 knockdown and HT reduced phosphorylation of the inhibitors of kappa B α (IκBα) and p65, a subunit of NF-κB, and degraded IκB kinase γ (IKKγ) during the recovery period after HT. Furthermore, BAG3 knockdown increased the HT-induced phosphorylation of ERK after HT treatment, and the ERK inhibitor U0126 significantly improved the viability of the cells treated with a combination of BAG3 knockdown and HT. CONCLUSIONS: The silencing of BAG3 seems to enhance the effects of HT, at least in part, by maintaining HT-induced inactivity of NF-κB and the phosphorylation of ERK. These findings indicate that BAG3 may be a potential molecular target for modifying the outcomes of HT in retinoblastoma.

Clinical efficacy and prognostic factors of chemoreduction combined with topical treatment for advanced intraocular retinoblastoma.

OBJECTIVE: To explore the clinical efficacy and prognostic factors of chemoreduction combined with topical treatment of advanced intraocular retinoblastoma (RB). MATERIALS AND METHODS: A total of 22 eyes from 17 children with RB were selected for the study and treated with chemoreduction combined with topical cryotherapy, transpupillary thermotherapy (TTT) or episcleral plaque brachytherapy. Clinical and follow-up data were retrospectively analyzed. RESULTS: All children received 2~6 courses of chemoreduction treatment, (4.5±0.8 courses on average); 17 eyes from 13 children were treated by chemoreduction combined with cryotherapy or TTT and 5 eyes from 4 children with chemoreduction combined with 125I episcleral plaque brachytherapy. The eye retention rate was 81.8% (18/22), among which 38.9% (7/18) featured restored or maintained good vision. Postoperative follow-up period was 7 to 34 months, (18.6 ± 5.2 months on average). The recurrence rate was 41.2% (7/17), among which 57.1% (4/7) were controlled by supplementing or appending cryotherapy or TTT treatment during the follow-up period. The tumor basal diameter and thickness were significantly reduced (P<0.05 or P<0.01) after treatment. All children demonstrated different degrees of hair loss, 70.6% (12/17) with different degrees of gastrointestinal reactions, 5.88% (1/17) with neutropenia and 11.8% (2/17) being seriously infected during the chemotherapeutic treatment. Univariate and logistic regression analysis showed that tumor basal diameter before treatment had a significant effect on the prognosis (P<0.01). CONCLUSIONS: Chemoreduction combined with topical therapy can effectively control RB in the short term, and tumor basal diameter before treatment is an independent risk factor for prognosis.

In vitro moxifloxacin drug interaction with chemotherapeutics: implications for retinoblastoma management.

Retinoblastoma (RB) is a common malignant intraocular tumor primarily affecting children. Multidrug resistance (MDR) proteins (P-gp and MRPs) mediated chemoresistance have been considered as a major cause of treatment failure in treatment of RB. Ocular cells have shown good tolerability against moxifloxacin (MFX). Hence, the aim of present study was to investigate the effect of moxifloxacin on the functionality of MDR proteins. Furthermore, we have also examined an interaction of MFX with anticancer agents (Topotecan, etoposide and vinblastine) for RB treatment. For interaction of MFX with efflux transporter, model cell lines transfected with the efflux transporters (MDCK-MDR1 and MDCK-MRP2) were used to perform uptake and bi-directional transport experiments. Modulation of anticancer induced cell cytotoxicity, pro-inflammatory cytokines (IL-6 and IL-8) release and caspase-3 enzyme activity in presence of MFX was also evaluated. Result indicates that MFX is a substrate of both MDR1 and MRP2 efflux transporters. Furthermore elevation of anticancer uptake and bi-directional transport, reduction in IC50 cytotoxic value and modulation of antiproliferative and cytokines release in presence of MFX by anticancer agents was observed. Our results demonstrate that MFX may not only modulate the permeability of anticancer agents at efflux sites but it may also potentiate antiproliferative activity of anticancer agents in retinoblastoma cells. This study may be further extended to explore in vivo outcome of this finding.

Inhibition of polo-like kinase 1 promotes hyperthermia sensitivity via inactivation of heat shock transcription factor 1 in human retinoblastoma cells.

PURPOSE: Hyperthermia (HT) has been recognized as an effective focal treatment in retinoblastoma. However, one of the problems with HT therapy is that cells acquire acquisition. The purpose of this study was to evaluate whether the inhibition of polo-like kinase 1 (PLK1) would promote HT sensitivity in human retinoblastoma cells. METHODS: We examined the effects of PLK1 knockdown by small interfering RNA (siRNA) or by the inhibition of PLK1 activity with PLK1 inhibitor (BI-2536) on the sensitivity to HT (44°C, 1 hour) in human retinoblastoma Y79 and WERI-Rb-1 cells by evaluating apoptosis and cell proliferation using flow cytometry, Western blotting, real-time quantitative polymerase chain reaction, and WST-8 assay. Furthermore, we investigated the effects of activating heat shock transcription factor 1 (HSF1) through a combination of PLK1 knockdown and HT using Western blotting and immunocytochemistry. RESULTS: The combination of PLK1 inhibition and HT enhanced sensitivity to HT synergistically. Furthermore, PLK1 knockdown inhibited HT-induced phosphorylation of HSF1, the nuclear translocation of HSF1 from the cytoplasm, and nuclear granule formation of HSF1. Heat shock transcription factor 1, inactivated by the silencing of PLK1, reduced the expression of heat shock proteins (HSPs), such as HSP70 and HSP40, as well as the expression of Bcl-2-associated athanogene 3 (BAG3). CONCLUSIONS: Polo-like kinase 1 inhibition may attenuate the thermoresistance of HT through the inactivation of HSF1 concomitant with reductions in HSPs and BAG3. The combination of PLK1 inhibition and HT may become an option for HT therapy in patients with retinoblastoma.

Artesunate exerts specific cytotoxicity in retinoblastoma cells via CD71.

Retinoblastoma (RB) is an intraocular cancer that affects young children. There is an ongoing effort to find new agents for RB management that are effective, specific and with few side-effects. In the present study, we tested artesunate (ART), a synthetic derivative from the herbal drug artemisinin, used in the clinic for the treatment of malaria. We analyzed ART cytotoxicity in an RB cell line (RB-Y79) and in a retinal epithelial cell line (hTERT-RPE1) by flow cytometric analysis (FCM). We related the effect of ART to the expression of transferrin receptor 1 (TfR-1, also known as CD71) by knocking down CD71 with RNAi and analyzing cell cycle variables by FCM. We found that the cytotoxic action of ART is specific for RB cells in a dose-dependent manner, with low toxicity in normal retina cells. ART is more effective in RB than carboplatin with a markedly strong cytotoxic effect on carboplatin-resistant RB cells. RB had higher CD71 levels at the membrane compared to normal retinal cells. We showed that ART internalization in RB cells is dependent upon the expression of the CD71. In addition, ART blocked the cell cycle progression at the G1 phase, even at low doses, and decreased the proportion of RB cells in the S phase. In conclusion, we showed that ART is a promising drug exhibiting high selective cytotoxicity even against multidrug-resistant RB cells. Thus, we suggest that ART could be used in the treatment of RB.

[Diagnosis and treatment of retinoblastoma: current strategies for effective tumour control and preservation of vision]. / Diagnose und behandlung des retinoblastoms: aktuelle konzepte zur sicheren tumorkontrolle bei erhalt des sehvermögens.

There are approximately 40 new cases of retinoblastoma in Germany per year. Children in whom the tumour is detected when still intraocular have an excellent overall survival rate (> 95%). However, the prognosis of metastasised retinoblastoma remains poor. About 40% of retinoblastoma patients have tumours in both eyes. For these children in particular it is important to save the eye and visual function as much as possible. There are several options for conservative treatment of localised retinoblastoma including laser coagulation, thermotherapy, cryotherapy, brachytherapy and chemotherapy. In recent years, systemic chemotherapy has become the established standard for primary treatment of intraocular retinoblastoma. In case series, intra-arterial, intravitreal and periocular applications of chemotherapy were also shown to be effective in treating intraocular retinoblastoma. Genetic testing is an integral part of the routine diagnostics of all patients. Mutation analysis of tumour material is invaluable for identification of somatic mutations including mutational mosaicism. Genetic testing also identifies children with heritable retinoblastoma, which represent 50% of cases. These children also have a predisposition for the development of tumours outside of the eye (second primary neoplasm). To adequately address these and other late effects in survivors of retinoblastoma, a multidisciplinary approach is needed that optimises therapy and long-term follow-up. Upcoming multicentre clinical trials will evaluate treatment concepts for localised and metastasised retinoblastoma to improve survival rates and quality of life of children with retinoblastoma. This article was translated and modified and was primarily published in Klin Padiatr 2012; 224: 339-347.

Regression patterns in treated retinoblastoma with chemotherapy plus focal adjuvant therapy.

PURPOSE: The aim of this study was evaluation of the regression patterns after 3, 6, and 8 months of treatment. METHODS: A total of 100 retinoblastoma tumors (57 eyes of 35 patients) were treated with 6 (n = 8) or 8 (n = 92) cycles of systemic chemoreduction and tumor consolidation (transpupillary thermotherapy [TTT] or cryotherapy) during this prospective study. RESULTS: After 3 months of treatment, type 3 was the predominant pattern (n = 57%, 57%), while after 6 and 8 months of treatment the tumors regressed to type 4 most often (44% and 52%, respectively). Smaller tumors and the peripheral tumors were likely to regress to type 4, whereas larger tumors and those nearer to fovea were more likely to become type 1 pattern. Tumors consolidated with cryotherapy mostly showed type 4 regression (3rd month: 40%, 6th month: 90%, and 8th month: 87.5%). Whereas, those treated with TTT rather regressed to type 3 after 3 months (57.9%) and to type 4 after 6 and 8 months of treatment (51.4% and 59.5%, respectively). Recurrence of the tumor was 40% in our cases with defined correlation with tumor location, size, and subretinal seeds. CONCLUSION: We conclude that regression patterns of tumors in patients undergoing systemic chemoreduction with focal adjuvant treatments predominantly changed over time and their changes are dependent on tumor size, location, and type of treatment. It appears that subretinal seeds, tumor size, and location of tumors are the most important factors predicting tumor recurrence.

Current concepts for diagnosis and treatment of retinoblastoma in Germany: aiming for safe tumor control and vision preservation.

Retinoblastoma affects approximately 40 children in Germany per year. Most children are diagnosed early with localized intraocular disease, and the overall survival rate exceeds 95%. However, the prognosis of metastasized retinoblastoma remains poor. In 40% of the patients, retinoblastoma occurs bilaterally and, especially for these children, the salvage of the eye and visual function is of major importance. The variety of conservative treatment options for localized retinoblastoma includes laser coagulation, thermotherapy, cryotherapy, brachytherapy and chemotherapy. While systemic chemotherapy has nearly completely replaced external beam radiotherapy in the primary treatment of intraocular retinoblastoma, intra-arterial, intravitreal and periocular application of chemotherapy was also shown to be effective in treating intraocular retinoblastoma in case series. Genetic testing is an integral part of the routine diagnostics of all patients. Available tumor material should be analyzed to detect mutational mosaicism, that affects >10% of children with unilateral retinoblastoma. Genetic testing also identifies children with heritable (50% of patients) retinoblastoma. These children have a genetic predisposition for second malignancies. For this reason, late effects are an increasing concern and the care of patients with retinoblastoma requires a multidisciplinary approach to tailor therapy and long-term follow-up. Multicenter clinical trials are being developed to evaluate evidence-based treatment concepts for localized and metastasized retinoblastoma to improve survival rates and quality of life of children with retinoblastoma.

[Retinoblastoma regression patterns and results following chemo reduction and adjuvant therapy].

OBJECTIVE: To evaluate retinoblastoma regression patterns following chemo reduction and adjuvant therapy. METHODS: Retrospective case series. 122 tumors of 47 eyes of 37 patients following chemo reduction and adjuvant therapy between January 2005 and June 2009 in the Eye & ENT hospital of Fudan University. Twenty-seven patients are male, and 10 patients are female. The average age was 22 months. The combined therapy included chemo reduction using vincristine, etoposide, and carboplatin (VEC) combined with local cryotherapy and/or transpupillary thermotherapy (TTT). The average follow-up duration was 32 months ranging from 12 to 60 months. Regression patterns included type 0 (no remnant), type 1 (calcified remnant), type 2 (noncalcified remnant), type 3 (partially calcified remnant), and type 4 (flat scar). Wilcoxon rank sum test was used to test the difference of tumor number between the patients with family history and those without family history. Chi-square test was used to test the difference between the tumor thickness, tumor location and regression patterns. Multivariate logistic regression analysis was used to test the correlation between the regression patterns and age, sex, tumor thickness, tumor location and family history. Statistical significance was assigned at P < 0.05. RESULTS: Forty-seven eyes according to the International Intraocular Retinoblastoma Classification, 20 eyes (42.6%) were group A, 13 eyes (27.6%) group B, 6 eyes (12.8%) group C, 8 eyes (17.0%) group D. Of 122 tumors, the average number of tumors per eye was 2.6. Retinoblastoma regressions were type 0 (n = 3), type 1 (n = 15), type 2 (n = 8), type 3 (n = 25), and type 4 (n = 71). Tumor thickness and tumor location were related to regression patterns. Tumors with an initial thickness of 2 mm or less regressed most often to type 4, and those thicker than 8 mm regressed to type 1 or type 3. Tumors with greater distance from the foveola regressed most often to type 4. The factors predictive of regression pattern type 1 included tumor thickness larger than 8 mm (Z = 3.02, P = 0.003). The factors predictive of regression pattern type 3 included older age, tumor thickness larger than 8 mm and location not in the equator to ora serrata region (Z = 3.98, 2.23, 3.60; P = 0.000, 0.025, 0.000). The factors predictive of regression pattern type 4 included familial hereditary pattern, tumor thickness smaller than 2 mm and location in the equator to ora serrata region. (Z = 4.37, 3.42, 2.42; P = 0.000, 0.000, 0.021). 12 tumors recurred, 9 tumors were type 3 and 3 tumors were type 4. 8 eyes developed 15 new tumors. 5 patients developed new tumors were all younger patients and had familial hereditary history. The average period of recurrence of main tumors and development of new tumors was six months after the end of chemo reduction. CONCLUSIONS: Following chemo reduction, type 3 and type 4 regression patterns were most common. Smaller tumors were usually seen in type 4, and bigger tumors were usually seen in type 1 or type 3. Tumor recurrence was usually found following regression pattern type 3 or type 4. Younger patients and patients with familial hereditary history trend to develop new tumors. Patients accept chemo reduction and adjuvant therapy need close follow-up.

Focused ultrasound facilitated thermo-chemotherapy for targeted retinoblastoma treatment: a modeling study.

Retinoblastoma is the most common type of intraocular tumors in children. Currently, with early detection and improved systemic chemo-adjuvant therapies, treatment paradigm has shifted from survival to globe salvation/vision preservation. The objective of our work has been to explore the possible application of focused ultrasound (FUS) for targeted drug delivery in the posterior pole retinoblastoma. Specifically, theoretical models were implemented to evaluate the feasibility of using FUS to generate localized hyperthermia in retinal tumor areas, for potential triggering the chemotherapeutic agent deployment from heat-sensitive drug carriers. In-vitro experiments were conducted in tissue-mimicking phantoms with embedded excised rabbit eyes to validate the reliability of the modeling results. After confirming the reliability of our model, various FUS transducer parameters were investigated to induce maximal hyperthermia coverage in the tumor, while sparing adjacent eye structures (e.g. the lens). The evaluated FUS parameters included operating frequency, total acoustic power, geometric dimensions, transducer f-number, standoff distance, as well as different pulsing scenarios. Our modeling results suggest that the most suitable ultrasound frequency for this type of treatments was in the range of 2-3.5 MHz depending on the size of retinoblastoma. Appropriate transducer f-number (close to 1) and standoff distance could be selected to minimize the risks of over-heating undesired regions. With the total acoustic power of 0.4 W, 56.3% of the tumor was heated to hyperthermic temperature range (39-44 °C) while the temperature in lens was maintained below 41 °C. In conclusion, FUS-induced hyperthermia for targeted drug delivery may be a viable option in treatments of juxta-foveal or posterior pole retinoblastomas. Future in-vivo studies will allow us to determine the effectiveness and safety of the proposed approach.