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Multiple myeloma (MM) is a plasma cell malignancy for which there is currently no cure. While treatment options for MM have expanded over the last two decades, all patients will eventually become resistant to current therapies. Thus, there is an urgent need for novel therapeutic strategies to treat MM. The isoprenoid biosynthetic pathway (IBP) is responsible for the post-translational modification of proteins belonging to the Ras small GTPase superfamily, such as Ras, Rho and Rab family members. Given the important roles these GTPase proteins play in various cellular processes, there is significant interest in the development of inhibitors that disturb their prenylation and consequently their activity in MM cells. Numerous preclinical studies have demonstrated that IBP inhibitors have anti-MM effects, including the induction of apoptosis in MM cells and inhibition of osteoclast activity. Some IBP inhibitors have made their way into the clinic. For instance, nitrogenous bisphosphonates are routinely prescribed for the management MM bone disease. Other IBP inhibitors, including statins and farnesyltransferase inhibitors, have been evaluated in clinical trials for MM, while there is substantial preclinical investigation into geranylgeranyl diphosphate synthase inhibitors. Here we discuss recent advances in the development of IBP inhibitors, assess their mechanism of action and evaluate their potential as anti-MM agents. [ABSTRACT FROM AUTHOR]

Geranylgeranyl diphosphate synthase (GGDPS), an enzyme in the isoprenoid biosynthesis pathway, is responsible for the production of geranylgeranyl pyrophosphate (GGPP). GGPP serves as a substrate for the post‐translational modification (geranylgeranylation) of proteins, including those belonging to the Ras superfamily of small GTPases. These proteins play key roles in signalling pathways, cytoskeletal regulation and intracellular transport, and in the absence of the prenylation modification, cannot properly localise and function. Aberrant expression of GGDPS has been implicated in various human pathologies, including liver disease, type 2 diabetes, pulmonary disease and malignancy. Thus, this enzyme is of particular interest from a therapeutic perspective. Here, we review the physiological function of GGDPS as well as its role in pathophysiological processes. We discuss the current GGDPS inhibitors under development and the therapeutic implications of targeting this enzyme. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the epidemiology and clinical characteristics of infants presenting with conjunctival, palpebral, or orbital congenital choristomas (dermolipomas, epidermoids, and dermoid cysts) and children undergoing surgery for congenital choristomas in the ocular adnexa. Methods: We reviewed the medical files of congenital choristomas in children seen in The Capital Region of Denmark during a 5-year period (2014–2018). Children (< 18 years) were divided into two groups: those referred < 1 year of age (Group I) and those undergoing surgery to remove the lesion (Group II). Group I was used to calculate a population-based incidence of congenital choristomas by comparing our data to birth statistics from the Danish Medical Birth Registry. Results: A total of 97 children were included, 43 in Group I and 70 in Group II (including 16 patients from Group I). The total incidence of congenital choristomas was 1 in 2537 live born children. Most lesions were palpebral choristomas (27/43, 63%) located in the superotemporal region (17/27, 63%), followed by the superonasal region (7/27, 26%). The main reasons for surgical removal of a congenital choristoma were growth (28/70, 40%) or cosmesis (25/70, 36%). Conclusion: The total incidence of congenital choristomas in the ocular adnexa of infants < 1 year of age, including both conjunctival and palpebral congenital choristomas, is about 1 in 2537 live born children in The Capital Region of Denmark. Hence, congenital choristomas are common masses found in the ocular adnexa. [ABSTRACT FROM AUTHOR]

The plasma cell neoplasm multiple myeloma (MM) is currently considered incurable. However, significant advances in treatment options over the past 20 years have led to unprecedented response rates to initial therapy as well as prolonged survival rates. Induction regimens have evolved from alkylator-based therapies to those consisting of immunomodulatory drugs and proteasome inhibitors. The combination of bortezomib/lenalidomide/dexamethasone (VRd) has emerged as a standard regimen for both transplant-eligible (TE) and transplant-ineligible (TI) patient populations. More recent efforts have focused on the incorporation of monoclonal antibody therapy into the newly diagnosed setting, particularly anti-CD38 monoclonal antibodies. In the TI patient population, the combination of daratumumab/lenalidomide/dexamethasone is now considered another standard therapy. In the TE setting, it remains to be determined whether the addition of daratumumab to the VRd backbone results in improved long-term outcomes. Recent studies have confirmed the progression-free survival benefit of upfront autologous stem cell transplant and have established lenalidomide maintenance as a standard of care. Multiple studies are evaluating whether inclusion of monoclonal antibody therapy in the maintenance setting will improve outcomes. The optimal management of newly diagnosed patients with high-risk cytogenetics remains to be determined. We discuss the emerging therapies that will likely shape management of newly diagnosed MM in the future. [ABSTRACT FROM AUTHOR]

The rising popularity of alcohol mixed with energy drinks (AmEDs) has become a significant public health concern, with AmED users reporting higher levels of alcohol intake than non-AmED users. One mechanism proposed to explain this heightened level of alcohol intake in AmED users is that the high levels of caffeine found in energy drinks may increase the positive reinforcing properties of alcohol, an effect that may be dependent on interactions between adenosine receptor signaling pathways and the dopamine D2 receptor. Therefore, the purpose of the current study was to confirm whether caffeine does increase the positive reinforcing effects of alcohol using both fixed ratio (FR) and progressive ratio (PR) designs, and to investigate a potential role of the dopamine D2 receptor to caffeine-induced increases in alcohol self-administration. Male Long-Evans rats were trained to self-administer a sweetened alcohol solution (10% v/v alcohol + 2% w/v sucrose) on an FR2 schedule of reinforcement, and the effects of caffeine (0, 5, 10, and 20 mg/kg, i. p. [intraperitoneally]) on the maintenance of alcohol self-administration and alcohol break point were examined. Parallel experiments in rats trained to self-administer sucrose (0.8% w/v) were conducted to determine whether caffeine's reinforcement-enhancing effects extended to a non-drug reinforcer. Caffeine pretreatment (5-10 mg/kg) significantly increased sweetened alcohol self-administration and motivation for a sweetened alcohol reinforcer. However, similar increases in self-administration of a non-drug reinforcer were not observed. Contrary to our hypothesis, the D2 receptor antagonist eticlopride did not block a caffeine-induced increase in sweetened alcohol self-administration, nor did it alter caffeine-induced increases in motivation for a sweetened alcohol reinforcer. Taken together, these results support the hypothesis that caffeine increases the positive reinforcing effects of alcohol, which may explain caffeine-induced increases in alcohol intake. However, the reinforcement-enhancing effects of caffeine appear to be independent of D2 receptor function. [ABSTRACT FROM AUTHOR]

• A comprehensive summary of the 2019 BMT CTN Myeloma Intergroup Minimal Residual Disease (MRD) and Immune Profiling (IP) workshop is provided. • MRD is a prognostic biomarker and should be incorporated into trial designs. • IP provides insight into disease biology and response to treatment. The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup has organized an annual workshop focused on minimal residual disease (MRD) testing and immune profiling (IP) in multiple myeloma since 2016. In 2019, the workshop took place as an American Society of Hematology (ASH) Friday Scientific Workshop titled "Immune Profiling and Minimal Residual Disease Testing in Multiple Myeloma." This workshop focused on 4 main topics: the molecular and immunologic evolution of plasma cell disorders, development of new laboratory- and imaging-based MRD assessment approaches, chimeric antigen receptor T cell therapy research, and statistical and regulatory issues associated with novel clinical endpoints. In this report, we provide a summary of the workshop and discuss future directions. [ABSTRACT FROM AUTHOR]

• CALGB (Alliance) 100001 evaluated tandem autologous/allogeneic transplant for myeloma. • A fludarabine/cyclophosphamide conditioning regimen was associated with a very low treatment-related mortality rate. • Long-term follow-up demonstrates a subset of patients who derived benefit from this approach. CALGB (Alliance) 100001 was a phase II study evaluating autologous stem cell transplant (ASCT) followed by nonmyeloablative allogeneic stem cell transplant (alloSCT) in patients with multiple myeloma who had received no more than 18 months of prior therapy and had experienced no more than 1 prior progression event. Conditioning for ASCT was with high-dose melphalan (200 mg/m2). The alloSCT reduced-intensity conditioning (RIC) regimen consisted of fludarabine (30 mg/m2/d i.v. on days -7 through -3) and cyclophosphamide (1 g/m2/d i.v. on days -4 through -3). The primary objective was to determine the 6-month post-alloSCT treatment-related mortality (TRM) rate. Additional objectives included determining the proportion of patients who could complete this tandem ASCT-alloSCT approach in a cooperative group setting, overall response rates, rates of donor chimerism, rates of graft-versus-host disease (GVHD), disease-free survival, and overall survival (OS). Sixty patients were enrolled, of whom 57 (95%) completed ASCT and 49 (82%) completed tandem ASCT-alloSCT. The TRM rate was 2% (1/49; 90% confidence interval, 0.10% to 9.3%). Moderate to severe (grades 2 to 3) acute GVHD was observed in 13 of 49 alloSCT patients (27%). One patient died due to GVHD within 9 months of alloSCT. Twenty-seven of the 49 patients (55%) who underwent alloSCT reported chronic GVHD as either limited (15/49; 31%) or extensive (12/49; 24%) in the first year post-alloSCT and prior to the start of nonprotocol therapy for progressive disease. With a median follow-up for survival of 11 years, the median OS time is 6.6 years and the median time to disease progression is 3.6 years. Similar to other studies, this study confirmed that tandem ASCT/alloSCT is associated with durable disease control in a subset of patients. This study demonstrated the feasibility of performing tandem ASCT/alloSCT in a cooperative group setting and determined that a fludarabine/cyclophosphamide RIC regimen is associated with a very low TRM rate. [ABSTRACT FROM AUTHOR]

Chemotherapy-related neurotoxicity (CRNT) is an emerging public health concern. Visual pathway degeneration may be a symptom of CRNT. We surveyed the current literature for evidence of visual pathway degeneration in cancer patients receiving chemotherapy. A systematic review was conducted in PubMed. Six published articles met our inclusion criteria. The studies showed reduced retinal thickness, primarily in the retinal nerve fibre layer, and impaired inner retinal function in patients receiving chemotherapy. In summary, the current literature suggests chemotherapy may induce visual pathway degeneration. Future research may benefit from improving study design, exploring mechanisms of chemotherapy-related visual pathway degeneration, and incorporating these findings into biomarker development. [ABSTRACT FROM AUTHOR]

• This is a comprehensive summary from the third annual Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Minimal Residual Disease (MRD) and Immune Profiling (IP) workshop. • MRD is not yet established as a surrogate endpoint but is a prognostic biomarker. • Incorporation of IP as an exploratory endpoint in trial design is recommended. The third annual Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup Workshop on Minimal Residual Disease and Immune Profiling was held on November 29, 2018, at the American Society of Hematology (ASH) annual meeting. This workshop featured the latest research focused on minimal residual disease (MRD) assessment and immune profiling (IP) in myeloma as well as discussion of the statistical and regulatory issues intrinsic to the development of MRD as a surrogate endpoint. In this report, we provide a summary of the workshop and focus on the integration of MRD and IP assessment into trial design and clinical practice. [ABSTRACT FROM AUTHOR]

Benzodiazepines are one of the most commonly prescribed anxiolytic drugs in America, and between 2006 and 2015 prescription rates increased by an estimated 27.1%. Weight gain is a common side effect of these drugs and it may result from increased feeding caused by drug-enhanced food palatability. We investigated the role of specific GABA A receptor subtypes involved with benzodiazepine-induced food consumption through third ventricle injections of L-838,417, a partial agonist of GABA A α2, α3, and α5 subunits, and a full antagonist of the α1 receptor subunit. A microanalysis of the licking behavior of adult male rats to a sucrose solution was used to isolate drug effects on specific consummatory behaviors that include: hedonic taste evaluation, food approach behavior, and oromotor function. L-838,417 dose-dependently increased intake through increases in the motivation to approach the solution (shorter pause intervals between bouts of licking) and through enhancement of measures associated with hedonic taste evaluation. Oromotor depressant effects previously associated with broad-spectrum benzodiazepine receptor agonists were not observed. These results indicate that nuclei in proximity to the ventricles respond to GABA A α2, α3, or α5 activation to induce motivation to feed, absent of α1 receptor subunit activation. Furthermore, activation of the α1 subunit is not necessary for benzodiazepine hyperphagia and may instead contribute to the oromotor depressant and sedative properties of classic benzodiazepine agonists. Hypothalamic nuclei such as the paraventricular nucleus may be involved in the benzodiazepine-increased motivation to feed, while the parabrachial nucleus of the hindbrain could contribute to benzodiazepine-induced enhancement of taste palatability. • The novel compound L-838,417 is a partial agonist of GABA A α2, α3, and α5 and a full antagonist of the α1 receptor subunit. • Dose-dependent ICV injections of L-838,417 increase hedonic taste evaluation and the motivation to consume sucrose. • L-838,417 did not affect satiation or satiety-related processes. • α2/α3/α5-containing GABA A receptors play a role in benzodiazepine-induced hyperphagia. [ABSTRACT FROM AUTHOR]

Highlights • Summary from the second annual BMT CTN Myeloma Intergroup minimal residual disease (MRD)/immune profiling (IP) workshop. • MRD is currently considered a prognostic biomarker from a regulatory perspective. • Additional prospective studies are required to develop MRD as a surrogate endpoint. • Standardization of immunophenotyping/IP studies is needed. Abstract The second annual Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup Workshop on Minimal Residual Disease and Immune Profiling was convened on December 7, 2017, at the American Society of Hematology (ASH) meeting. During this workshop, investigators from around the world presented their latest research involving assessment of minimal residual disease (MRD) and immune profiling (IP) in myeloma. This document summarizes the workshop presentations as well as relevant ASH abstracts and focuses on the regulatory issues involved in the integration of MRD and IP assessment in clinical trial design and practice. [ABSTRACT FROM AUTHOR]

Purpose: Lacrimal gland tumours constitute a wide spectrum of neoplastic lesions that are histologically similar to tumours of the salivary gland. In the salivary gland, pleomorphic adenoma (PA) is frequently characterized by recurrent chromosomal rearrangements of the PLAG1 and HMGA2 genes, a genetic feature retained in carcinoma ex pleomorphic adenoma (ca‐ex‐PA) that makes it possible to distinguish ca‐ex‐PA from de novo carcinomas. However, whether PLAG1 and HMGA2 gene rearrangements are found in lacrimal gland PA and ca‐ex‐PA is not known. Methods: Twenty‐one lacrimal gland PAs and four ca‐ex‐PAs were retrospectively reviewed and subjected to break‐apart fluorescence in situ hybridization (FISH) for rearrangements of the PLAG1 gene. Cases without PLAG1 abnormalities were subjected to HMGA2 break‐apart FISH. Immunohistochemical staining for PLAG1 and HMGA2 protein was performed and correlated with gene status. Results: Sixteen of 21 PAs showed rearrangement of PLAG1 and were all positive for PLAG1 protein. Two of the remaining five PAs showed rearrangement of HMGA2 and were the only cases positive for HMGA2 with immunohistochemistry. The three FISH‐negative PAs expressed PLAG1 protein. All four ca‐ex‐PAs showed rearrangement of PLAG1 and expressed PLAG1 protein. None of the de novo carcinomas showed rearrangement of either of the two genes or expression of the two proteins. Conclusion: Rearrangement of PLAG1 and HMGA2 and expression of the corresponding proteins are frequent and specific findings in lacrimal gland PA and ca‐ex‐PA. The mechanism for PLAG1 overexpression in FISH‐negative PAs is yet to be clarified. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is the second most common hematologic malignancy with an increasing incidence and prevalence. The wide array of effective antimyeloma agents have transformed MM into a chronic condition for some patients, requiring long-term management planning. Immunomodulatory drugs and proteasome inhibitors have played a pivotal role in defining the most effective regimens for both transplantation-eligible and transplantation-ineligible subgroups. Nevertheless, recent approvals of immunotherapies in MM such as daratumumab have added another important component to combination treatments for both relapsed or refractory and newly diagnosed disease. Evolving novel therapies such as chimeric antigen receptor T cells are poised to raise the bar even further, holding a promise of effective treatment option for patients who would otherwise have limited treatment alternatives. As we continue to therapeutically exploit the essential roles of cell-mediated immune surveillance, antigen presentation, and modulation of inhibitory surface signaling, we are rapidly establishing the cornerstone role of immunotherapies in the management of all phases of MM. In this review, we will cover the spectrum of available immunotherapies approved for clinical use in MM, as well as briefly describe those in early- and late-phase development, with the focus of raising the awareness of the expanding immuno-oncology armamentarium in MM. [ABSTRACT FROM AUTHOR]

The Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Minimal Residual Disease and Immune Profiling was convened on December 1, 2016 at the American Society of Hematology meeting to discuss the emerging data and technologies for minimal residual disease assessment and immune profiling in myeloma. Particular emphasis was placed on developing strategies to incorporate these techniques into clinical trial design. This document reviews the literature, summarizes the topics discussed in the workshop, and provides recommendations for integration of these techniques into future clinical trial design. [ABSTRACT FROM AUTHOR]

Adolescence is a developmental period characterized by unique behavioral phenotypes (increased novelty seeking, risk taking, sociability and impulsivity) and increased risk for destructive behaviors, impaired decision making and psychiatric illness. Adaptive and maladaptive adolescent traits have been associated with development of the medial prefrontal cortex (mPFC), a brain region that mediates regulatory control of behavior. However, the molecular changes that underlie brain development and behavioral vulnerability have not been fully characterized. Using high-throughput 2D DIGE spot profiling with identification by MALDI-TOF mass spectrometry, we identified 62 spots in the PFC that exhibited age-dependent differences in expression. Identified proteins were associated with diverse cellular functions, including intracellular signaling, synaptic plasticity, cellular organization and metabolism. Separate Western blot analyses confirmed age-related changes in DPYSL2, DNM1, STXBP1 and CFL1 in the mPFC and expanded these findings to the dorsal striatum, nucleus accumbens, motor cortex, amygdala and ventral tegmental area. Ingenuity Pathway Analysis (IPA) identified functional interaction networks enriched with proteins identified in the proteomics screen, linking age-related alterations in protein expression to cellular assembly and development, cell signaling and behavior, and psychiatric illness. These results provide insight into potential molecular components of adolescent cortical development, implicating structural processes that begin during embryonic development as well as plastic adaptations in signaling that may work in concert to bring the cortex, and other brain regions, into maturity. [ABSTRACT FROM AUTHOR]

Over the last two decades, the outcomes for patients with multiple myeloma, a plasma cell malignancy, have dramatically improved. The development of the immunomodulatory drugs (IMiDs), which include thalidomide, lenalidomide, and pomalidomide, has contributed significantly to these improved outcomes. While thalidomide is now less commonly prescribed, lenalidomide is widely used in the treatment of newly diagnosed transplant-eligible and transplant-ineligible patients, in the maintenance setting post-transplant and in the relapsed/refractory setting, while pomalidomide is currently utilized in the relapsed/refractory setting. The IMiDs have been reported to have a multitude of activities, including anti-angiogenic, cytotoxic, and immunomodulatory. However, the more recent discoveries that the IMiDs bind to cereblon and thus regulate the ubiquitination of key transcription factors including IKZF1 and IKZF3 have provided greater insight into their mechanism of action. Here, the clinical efficacy of these agents in myeloma is reviewed and the structure-function relationship, the molecular mechanisms of action, and the association of IMiDs with second primary malignancies and thrombosis are discussed. [ABSTRACT FROM AUTHOR]

Increased binge alcohol consumption has been reported among adolescents as compared to adults in both humans and rodent models, and has been associated with serious long-term health consequences. However, the neurochemical mechanism for age differences in binge drinking between adolescents and adults has not been established. The present study was designed to evaluate the mechanistic role of the cannabinoid CB1 receptor in adolescent and adult binge drinking. Binge consumption was established in adolescent and adult male C57BL/6J mice by providing access to 20% alcohol or 1% sucrose for 4 h every other day. Pretreatment with the CB1 antagonist/inverse agonist AM-251 (0, 1, 3, and 10 mg/kg) in a Latin square design dose-dependently reduced adolescent alcohol consumption to adult levels without altering adult intake. AM-251 (3 mg/kg) also reduced adolescent but not adult sucrose consumption. Adolescent reductions in alcohol and sucrose were not associated with alterations in open-field locomotor activity or thigmotaxis. These findings point to age differences in CB1 receptor activity as a functional mediator of adolescent-typical increased binge drinking as compared to adults. Developmental alterations in endocannabinoid signaling in the adolescent brain may therefore be responsible for the drinking phenotype seen in this age group. [ABSTRACT FROM AUTHOR]

Background Binge drinking during adolescence is associated with increased risk for developing alcohol use disorders; however, the neural mechanisms underlying this liability are unclear. In this study, we sought to determine whether binge drinking alters expression or phosphorylation of 2 molecular mechanisms of neuroplasticity, calcium/calmodulin-dependent kinase II alpha (Ca MKII α) and the GluA1 subunit of AMPA receptors ( AMPARs) in addiction-associated brain regions. We also asked whether activation of Ca MKII α-dependent AMPAR activity escalates binge-like drinking. Methods To address these questions, Ca MKII αT286 and GluA1S831 protein phosphorylation and expression were assessed in the amygdala and striatum of adolescent and adult male C57 BL/6J mice immediately after voluntary binge-like alcohol drinking (blood alcohol >80 mg/dl). In separate mice, effects of the Ca MKII α-dependent GluA1S831 phosphorylation (pGluA1S831)-enhancing drug tianeptine were tested on binge-like alcohol consumption in both age groups. Results Binge-like drinking decreased Ca MKII αT286 phosphorylation ( pCaMKII αT286) selectively in adolescent amygdala with no effect in adults. Alcohol also produced a trend for reduced pGluA1S831 expression in adolescent amygdala but differentially increased pGluA1S831 in adult amygdala. No effects were observed in the nucleus accumbens or dorsal striatum. Tianeptine increased binge-like alcohol consumption in adolescents but decreased alcohol consumption in adults. Sucrose consumption was similarly decreased by tianeptine pretreatment in both ages. Conclusions These data show that the adolescent and adult amygdalae are differentially sensitive to effects of binge-like alcohol drinking on plasticity-linked glutamate signaling molecules. Tianeptine-induced increases in binge-like drinking only in adolescents suggest that differential Ca MKII α-dependent AMPAR activation may underlie age-related escalation of binge drinking. [ABSTRACT FROM AUTHOR]

A 77-year-old female, with proptosis, reduced eye motility and diplopia which had developed over two to three months and a 69-year-old female with proptosis, oedema of the eyelid, reduced motility and ptosis, which had developed over three weeks, are presented in the present study. Computed tomography scans revealed irregular lacrimal gland tumours in the two patients. The two patients had history of breast cancer. The first breast cancer metastasis in the lacrimal gland demonstrated a cribriform growth pattern containing ductal elements. The epithelial tumour cells stained positive for cytokeratin (1-8, 10, 14-16, 18 and 19), oestrogen receptor, epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA) and gross cystic disease fluid protein 15 (GCDFP-15). The second metastatic tumour was positive for EMA and estrogen receptor, but variably positive for CEA and GCDFP-15. The metastasis in the lacrimal gland was a pleomorphic tumour. The tumour cells were positive for EMA and variably positive for oestrogen and CEA. Metastases to the lacrimal gland are extremely rare, and metastases to the lacrimal gland should be considered in the diagnoses of lacrimal gland tumours. The present study aimed to describe two such cases and draw attention to breast carcinomas as a differential diagnosis and the most frequent cause of lacrimal gland metastasis. [ABSTRACT FROM AUTHOR]

Autologous stem cell transplantation (ASCT) remains a standard of care for multiple myeloma patients who are eligible to receive high-dose therapy, recognizing that the optimal timing and integration of this approach is now under study in a number of randomized trials. Despite the improved response rates with induction therapy consisting of immunomodulatory drugs and/or proteasome inhibitors, as well as the increasing use of post-ASCT maintenance therapy, most myeloma patients relapse and die of their disease. Here we discuss the options for managing post-ASCT relapse, including the role of various salvage regimens in the setting of relapsed and refractory myeloma, salvage ASCT, and salvage allogeneic SCT. [ABSTRACT FROM AUTHOR]

Purpose: To study genetic alterations in lacrimal gland pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma (Ca-ex-PA) with focus on copy number changes and expression patterns of the trans- location target genes PLAG1, HMGA2, and CRTC1-MAML2 in relation to clinical data. Design: Experimental study. Participants: A total of 36 tumors from 32 patients with lacrimal gland PA or Ca-ex-PA were included in the study. Methods: Genome wide, high-resolution array-based comparative genomic hybridization (arrayCGH) and immunohistochemistry were used to study the genomic profiles and expression patterns of the translocation targets PLAG1, HMGA2, and CRTC1-MAML2. Main Outcome Measures: Copy number alterations (gains/losses) and protein expression of PLAG1, HMGA2, and CRTC1-MAML2. Results: Genome-wide arrayCGH analysis revealed normal genomic profiles in 10 of 17 PA samples. The average number of genomic imbalances per tumor was 3.25 (range, 1-7) in primary and recurrent PAs with alterations compared with 7.7 (range, 4-12) in Ca-ex-PAs. Five recurrent copy number alterations were identified in PAs, including losses of 1pter-p31.3, 6q22.1-q24.3, 8q24.22-q24.3, and 13q21.31-q21.33, and gain of 9p23- p22.3. Gain of 9p23-p22.3 also was seen in a Ca-ex-PA. In Ca-ex-PA, gain of 22q12.3-qter was the only recurrent alteration. Detailed analysis of the array data identified NFIB and PDGFB as the 2 major candidate target oncogenes that may be activated as a result of copy number gains involving 9p and 22q. Both genes have been implicated in the pathogenesis of PA and other types of salivary gland tumors. Immunohistochemical analysis revealed frequent overexpression of the translocation target gene PLAG1 in PAs and in 1 Ca-ex-PA. In contrast, overexpression of HMGA2 was observed in only a small subset of PAs. The CRTC1-MAML2 fusion oncoprotein was overexpressed in 2 mucoepidermoid Ca-ex-PAs. Conclusions: Lacrimal and salivary gland PAs and Ca-ex-PAs have similar genomic profiles and frequently overexpress the PLAG1 oncoprotein. Copy number gains involving 9p23-p22.3 (NFIB) and 22q12-qter (PDGFB) may be of importance for disease progression in a subset of lacrimal gland PAs. [ABSTRACT FROM AUTHOR]

Tumours of the lacrimal gland are rare, but the prognosis may be grave. To date, no population-based incidence and distribution data on lacrimal gland tumours exist. In addition, almost nothing is known about the genetic profile of epithelial tumours of the lacrimal gland. We collected specimens and clinical files on all biopsied lacrimal gland lesions in Denmark over a 34-year period and re-evaluated the diagnosis to provide updated population-based incidence rates and epidemiological characteristics. Clinical data regarding symptoms, clinical examinations, treatment and follow-up were collected for patients with adenoid cystic carcinoma ( ACC), pleomorphic adenoma ( PA), carcinoma ex pleomorphic adenoma (Ca-ex- PA) and mucoepidermoid carcinoma ( MEC). Using RT- PCR, FISH, immunohistochemistry, Q- PCR and high-resolution array-based comparative genomic hybridization (array CGH) we explored the genetic characteristics including copy number alterations ( CNA) in ACC, PA, Ca-ex- PA and MEC. The incidence of biopsied lacrimal gland lesions was 1.3/1 000 000/year, and ~50% were neoplastic lesions. Of these, 55% were malignant tumours with epithelial tumours as the most frequent. The overall incidence was increasing, and this was caused by an increase in biopsied non-neoplastic lesions. We found that 10/14 ACCs either expressed the MYB- NFIB fusion gene and/or had rearrangements of MYB. All ACCs expressed the MYB protein. ACC was characterized by recurrent copy number losses involving 6q, 12q and 17q and gains involving 19q, 8q and 11q. Array CGH revealed an apparently normal genomic profile in 11/19 PAs. The remaining 8 PAs had recurrent copy number losses involving 1p, 6q, 8q and 13q and gain involving 9p. PA expressed PLAG1 in all tumours whereas only 2/29 tumours expressed HMGA2. Ca-ex- PA was characterized by recurrent copy number gain involving 22q. PLAG1 was expressed in 3/5 Ca-ex- PA whereas none of these tumours expressed HMGA2. MEC expressed the CRTC1- MAML2, and this fusion was found to be tumour-specific for lacrimal gland MEC. In conclusion, lacrimal gland lesions that require pathological evaluation are rare in the Danish population, and the incidence rate of biopsied benign lesions is increasing. Epithelial tumours of the lacrimal gland are molecularly very similar to their salivary gland counterparts in the expression of the tumour-specific fusion genes and in their genomic imbalances as demonstrated by array CGH. MYB- NFIB is a useful biomarker for ACC and MYB, and its downstream target genes may be potential therapeutic targets for these tumours. [ABSTRACT FROM AUTHOR]

Purpose: To investigate genetic alterations in lacrimal gland adenoid cystic carcinomas (ACCs) with emphasis on the MYB-NFIB fusion oncogene and its downstream targets, MYB rearrangements, and copy number alterations in relation to clinical data and survival. Design: Experimental study. Participants and Controls: Fourteen patients with primary lacrimal gland ACC were included. As a control, we also studied the expression of MYB-NFIB in 19 non-ACC lacrimal gland tumors. Methods: The expression and identity of MYB-NFIB fusion transcripts were studied using reverse transcriptase polymerase chain reaction (RT-PCR) and nucleotide sequence analyses. Quantitative polymerase chain reaction (PCR) and immunohistochemistry were used to evaluate the expression of MYB/MYB-NFIB target genes. High-resolution array-based comparative genomic hybridization (arrayCGH) and fluorescence in situ hybridization were used to study copy number alterations and MYB rearrangements. Main Outcome Measures: mRNA or protein expression of MYB-NFIB, MYB, and its down stream targets; copy number alterations; and genomic rearrangements. Results: The median age of the patients was 43 years (equal gender distribution), and the median time of survival was 8.6 years. The MYB-NFIB fusion was expressed in 7 of 14 ACCs. In contrast, all non-ACC tumors were fusion-negative. All 13 ACCs tested stained positive for the MYB protein, and for the MYB targets KIT and BCL2, 12 were positive for MYC and CCNE1, and 9 were positive for CCNB1. Rearrangements of MYB were detected in 8 of 13 cases, including 2 cases with gain of an apparently intact MYB gene. The arrayCGH analysis revealed recurrent copy number alterations with losses involving 6q23-q27, 12q12-q14.1, and 17p13.3-p12, and gains involving 19q12, 19q13.31-qter, 8q24.13-q24.21, 11q12.3-q14.1, and 6q23.3. Neither MYB-NFIB fusion nor any copy number alteration correlated with survival. Conclusions: Lacrimal gland ACCs are frequently positive for the MYB-NFIB fusion, overexpress MYB and its downstream targets, and have genomic profiles characterized by losses involving 6q, 12q, and 17p, and gains involving 19q, 8q, and 11q. Our findings show that lacrimal gland ACCs are genetically and clinically similar to their salivary gland counterparts and that MYB-NFIB is a clinically useful diagnostic biomarker for ACC. Our data also suggest that MYB and its downstream targets are potential therapeutic targets for these tumors. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article. [Copyright &y& Elsevier]

. Purpose: To evaluate the incidence rate, distribution, patient characteristics and indications for surgical intervention of lacrimal gland lesions in Denmark between 1974 and 2007. Material and methods: All biopsied/surgically removed lacrimal gland lesions in Denmark during the period 1974-2007 were identified by searching two population-based registries. Specimens were collected and re-evaluated. The following data were collected: age, gender, indications for surgical intervention and local recurrence. Results: A total of 232 lesions from 210 patients with a histologically verified lesion of the lacrimal gland were included. The incidence rate of lacrimal gland lesions was 1.3/1 000 000/year. The overall annual age- and gender-adjusted incidence rate more than doubled during the study period, owing to an increase in non-malignant lesions. Approximately half of the lesions were neoplasms (119) and 55% (66) of these were malignant. Dacryops constituted 10% (24), inflammatory lesions 27% (62), normal tissue 12% (27), benign tumours 23% (53) and malignant tumours 29% (66). Patients with malignant neoplasms were significantly older than patients with benign neoplasms (63 versus 48 years, p < 0.001). The indication for surgical intervention was suspicion of a tumour in more than 90% of the neoplastic lesions and in 30% of the non-neoplastic lesions. Conclusion: Lacrimal gland lesions that require surgical evaluation are rare in the Danish population and represent a wide spectrum of diagnoses, mostly benign. The overall incidence rate of biopsied lacrimal gland lesions is increasing. [ABSTRACT FROM AUTHOR]

. Epithelial tumours of the lacrimal gland represent a large spectrum of lesions with similarities in clinical signs and symptoms but with different biological behaviour and prognosis. They are rare, but with aggressive malignant potential. Tumours of the lacrimal gland may present with swelling of the lacrimal gland, displacement of the eyeball, reduced eye motility and diplopia. Pain and symptoms of short duration before the first ophthalmic consultation are characteristic of malignant tumours. The histological diagnosis determines the subsequent treatment regimen and provides important clues regarding the prognosis. The purpose of this paper is to describe the various primary epithelial tumours of the lacrimal gland. In the first part of the review, the frequency, demographics, clinical presentation and diagnostic features are described. In the second part, primarily tumour-specific histological characteristics are given. Finally, treatment modalities including surgical procedures and medical oncology as well as prognosis are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Neural processes influenced by γ-aminobutyric acid B (GABAB) receptors appear to contribute to acute ethanol sensitivity, including the difference between lines of mice bred for extreme sensitivity (FAST) or insensitivity (SLOW) to the locomotor stimulant effect of ethanol. One goal of the current study was to determine whether selection of the FAST and SLOW lines resulted in changes in GABAB receptor function, since the lines differ in sensitivity to the GABAB receptor agonist baclofen and baclofen attenuates the stimulant response to ethanol in FAST mice. A second goal was to determine whether the baclofen-induced reduction in ethanol stimulation in FAST mice is associated with an attenuation of the mesolimbic dopamine response to ethanol. In Experiment 1, the FAST and SLOW lines were found to not differ in GABAB receptor function (measured by baclofen-stimulated [35S]GTPγS binding) in whole brain or in several regional preparations, except in the striatum in one of the two replicate sets of selected lines. In Experiment 2, baclofen-induced attenuation of the locomotor stimulant response to ethanol in FAST mice was not accompanied by a reduction in dopamine levels in the nucleus accumbens, as measured by microdialysis. These data suggest that, overall, GABAB receptor function does not play an integral role in the genetic difference in ethanol sensitivity between the FAST and SLOW lines. Further, although GABAB receptors do modulate the locomotor stimulant response to ethanol in FAST mice, this effect does not appear to be due to a reduction in tonic dopamine signaling in the nucleus accumbens. [Copyright &y& Elsevier]

It has been over 20 years since it was first recognized that the function of both normal and oncogenic Ras is dependent on the post-translational modification termed farnesylation. Since that time, intense effort has been expended on the development of farnesyltransferase inhibitors as novel anticancer agents. Over 70 clinical trials have now been conducted, with limited efficacy demonstrated. Here we provide an update of the most recently published clinical trials, discuss the use of the RASGRP1/APTX two-gene expression screen to select patients with acute myeloid leukemia for therapy, and report on the latest discoveries related to the targets of prenyltransferase inhibitors. [Copyright &y& Elsevier]

Background: Binge alcohol drinking during adolescence is a serious health problem that may increase future risk of an alcohol use disorder. Although there are several different procedures by which to preclinically model binge-like alcohol intake, limited-access procedures offer the advantage of achieving high voluntary alcohol intake and pharmacologically relevant blood alcohol concentrations (BACs). Therefore, in the current study, developmental differences in binge-like alcohol drinking using a limited-access cycling procedure were examined. In addition, as alcohol drinking has been negatively correlated with sensitivity to the aversive properties of alcohol, we examined developmental differences in sensitivity to an alcohol-induced conditioned taste aversion (CTA). Methods: Binge-like alcohol consumption was investigated in adolescent (4 weeks) and adult (10 weeks) male C57BL/6J mice for 2 to 4 h/d for 16 days. Developmental differences in sensitivity to an alcohol-induced CTA were examined in adolescent and adult mice, with saline or alcohol (3 or 4 g/kg) repeatedly paired with the intake of a novel tastant (NaCl). Results: Adolescent mice showed a significant increase in alcohol intake as compared to adults, with adolescents achieving higher BACs and increasing alcohol consumption over successive cycles of the binge procedure. Conversely, adolescent mice exhibited a dose-dependent reduction in sensitivity to the aversive properties of alcohol, as compared to adult mice, with adolescent mice failing to develop a CTA to 3 g/kg alcohol. Finally, extinction of an alcohol CTA was observed following conditioning with a higher dose of alcohol in adolescent, versus adult, mice. Conclusions: These results indicate that adolescent mice consume more alcohol, per kilogram body weight, than adults in a binge-like model of alcohol drinking and demonstrate a blunted sensitivity to the conditioned aversive effects of alcohol. Overall, this supports a behavioral framework by which heightened binge alcohol intake during adolescence occurs, in part, via a reduced sensitivity to the aversive properties of alcohol. [ABSTRACT FROM AUTHOR]

Abstract: Myeloma is characterized by the overproduction and secretion of monoclonal protein. Inhibitors of the isoprenoid biosynthetic pathway (IBP) have pleiotropic effects in myeloma cells. To investigate whether IBP inhibition interferes with monoclonal protein secretion, human myeloma cells were treated with specific inhibitors of the IBP or prenyltransferases. These studies demonstrate that agents that inhibit Rab geranylgeranylation disrupt light chain trafficking, lead to accumulation of light chain in the endoplasmic reticulum, activate the unfolded protein response pathway and induce apoptosis. These studies provide a novel mechanism of action for IBP inhibitors and suggest that further exploration of Rab-targeted agents in myeloma is warranted. [Copyright &y& Elsevier]

Abstract: Thalidomide has emerged as an effective agent for treating multiple myeloma, however the precise mechanism of action remains unknown. Agents known to target the isoprenoid biosynthetic pathway (IBP) can have cytotoxic effects in myeloma cells. The interactions between thalidomide and IBP inhibitors in human multiple myeloma cells were evaluated. Enhanced cytotoxicity and induction of apoptosis were observed in RPMI-8226 cells. Examination of intracellular levels of farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP) revealed a wide variance in basal levels and response to IBP inhibitors. These findings provide a mechanism for the differential sensitivity of myeloma cells to pharmacologic manipulation of the IBP. [Copyright &y& Elsevier]

Abstract: Tyrosine kinase inhibitors (TKIs) directed against the Bcr-Abl kinase have revolutionized the treatment of chronic myelogenous leukemia (CML). Relatively little is known regarding the effects of these agents on the kidney. Clinically, there have been a handful of reports associating imatinib with acute renal failure. Preclinical reports indicate that imatinib inhibits signaling pathways which may play a role in renal injury. We report the case of a patient with imatinib-resistant CML who developed renal failure after being placed on dasatinib. When she later became resistant to dasatinib she was switched to nilotinib. Shortly thereafter, she became dialysis-independent. Second-generation Bcr-Abl TKIs may influence renal function based on differential inhibition of related tyrosine kinases. [Copyright &y& Elsevier]

Background: The γ-aminobutyric acid (GABA) system is implicated in the neurobiological actions of ethanol, and pharmacological agents that increase the activity of this system have been proposed as potential treatments for alcohol use disorders. As ethanol has its own GABA mimetic properties, it is critical to determine the mechanism by which GABAergic drugs may reduce the response to ethanol (i.e., via an inhibition or an accentuation of the neurobiological effects of ethanol). Methods: In this study, we examined the ability of 3 different types of GABAergic compounds, the GABA reuptake inhibitor NO-711, the GABAA receptor agonist muscimol, and the GABAB receptor agonist baclofen, to attenuate the locomotor stimulant response to ethanol in FAST mice, which were selectively bred for extreme sensitivity to ethanol-induced locomotor stimulation. To determine whether these compounds produced a specific reduction in stimulation, their effects on ethanol-induced motor incoordination were also examined. Results: NO-711, muscimol, and baclofen were all found to potently attenuate the locomotor stimulant response to ethanol in FAST mice. However, both NO-711 and muscimol markedly increased ethanol-induced ataxia, whereas baclofen did not accentuate this response. Conclusions: These results suggest that pharmacological agents that increase extracellular concentrations of GABA and GABAA receptor activity may attenuate the stimulant effects of ethanol by accentuating its intoxicating and sedative properties. However, selective activation of the GABAB receptor appears to produce a specific attenuation of ethanol-induced stimulation, suggesting that GABAB receptor agonists may hold greater promise as potential pharmacotherapies for alcohol use disorders. [ABSTRACT FROM AUTHOR]

Abstract: Mice selectively bred for divergent sensitivity to the locomotor stimulant effects of ethanol (FAST and SLOW) also differ in their locomotor response to morphine. The GABAB receptor has been implicated in the mediation of locomotor stimulation to both ethanol and morphine, and a reduction in ethanol-induced stimulation has been found with the GABAB receptor agonist baclofen in FAST mice. We hypothesized that GABAB receptor activation would also attenuate the locomotor stimulant responses to morphine in these mice. In order to test this hypothesis, baclofen was administered to FAST-1 and FAST-2 mice 15 min prior to morphine, and activity was recorded for 30 min. Baclofen attenuated stimulation to 32 mg/kg morphine in FAST-1 mice, but only at a dose that also reduced saline activity. There was no stimulant response to 32 mg/kg morphine in FAST-2 mice, or to 16 mg/kg or 48 mg/kg morphine in FAST-1 mice, but the combination of baclofen with these morphine doses accentuated locomotor activity. Therefore, it appears that GABAB receptor activation is not a common mechanism for the locomotor stimulant responses to ethanol and morphine in FAST mice; however, these data suggest that GABAB receptor activation may instead enhance some of the behavioral effects of morphine. [Copyright &y& Elsevier]

Lovastatin, an inhibitor of the rate-limiting enzyme in the cholesterol biosynthetic pathway, hydroxymethylglutaryl coenzyme A reductase, has shown interesting antiproliferative activities in cell culture and in animal models of cancer. The goal of the current study is to determine whether lovastatin bioactivity levels, in a range equivalent to those used in in vitro and preclinical studies, can be safely achieved in human subjects. Here we present the findings from a dose-escalating trial of lovastatin in subjects with advanced malignancies. Lovastatin was administered every 6 h for 96 h in 4-week cycles in doses ranging from 10 mg/m2 to 415 mg/m2. Peak plasma lovastatin bioactivity levels of 0.06–12.3 μM were achieved in a dose-independent manner. Cholesterol levels decreased during treatment and normalized during the rest period. A dose-limiting toxicity was not reached and there were no clinically significant increases in creatine phosphokinase or serum hepatic aminotransferases levels. No antitumor responses were observed. These results demonstrate that high doses of lovastatin, given every 4 h for 96 h, are well-tolerated and in select cases, bioactivity levels in the range necessary for antiproliferative activity were achieved. [ABSTRACT FROM AUTHOR]

Rationale: Previous studies suggest that some behavioral effects of ethanol and morphine are genetically correlated. For example, mice bred for sensitivity (FAST) or insensitivity (SLOW) to the locomotor stimulant effects of ethanol differ in their locomotor response to morphine. Objective: To evaluate a possible common mechanism for these traits, we examined the effect of naloxone, an opioid receptor antagonist, on ethanol- and morphine-induced locomotion in FAST and SLOW mice, as well as on ethanol- induced locomotion in two heterogeneous stocks of mice. Method: In experiments 1 and 2, naloxone was given to FAST and SLOW mice 30 min prior to 2 g/kg ethanol or 32 mg/kg morphine, and locomotor activity was measured for 15 min (ethanol) or 30 min (morphine). In experiments 3 and 4, naloxone was administered 30 min prior to 1.25 g/kg ethanol, and locomotor activity was assessed in FAST mice and in a heterogeneous line of mice [Withdrawal Seizure Control (WSC)]. Experiment 5 assessed the effect of naloxone on ethanol-induced stimulation in outbred National Institutes of Health (NIH) Swiss mice. Results: There was no effect of naloxone on the locomotor response to ethanol in FAST, SLOW, WSC, or NIH Swiss mice. However, naloxone did significantly attenuate the locomotor effects of morphine in FAST and SLOW mice. Conclusions: These results suggest that a common opioidergic mechanism is not responsible for the correlated locomotor responses to ethanol and morphine in FAST and SLOW mice, and that activation of the endogenous opioid system is not critical for the induction of ethanol-induced alterations in activity. [ABSTRACT FROM AUTHOR]

Abstract: Lovastatin, a competitive inhibitor of hydroxymethylglutaryl coenzyme A reductase (HMGR), is used therapeutically to lower plasma cholesterol levels and has garnered attention for its cytotoxic effects in leukemia cells. In this study, escalating doses of lovastatin were administered to nine patients with acute myelogenous leukemia. Peripheral blood leukemia cells were drawn pre- and post-lovastatin dosing. Plasma lovastatin bioactivity ranged up to 234nM lovastatin equivalents. Our results show that in vivo lovastatin, at up to 200mg/dose, induces an increased activity of leukemia cell HMGR and alters leukemia cell proliferation without discernibly altering Ras processing. [Copyright &y& Elsevier]

Abstract: A sensitive, nonradioactive analytical method has been developed to simultaneously determine the concentrations of farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP) in cultured cells. Following extraction, enzyme assays involving recombinant farnesyl protein transferase or geranylgeranyl protein transferase I are performed to conjugate FPP or GGPP to dansylated peptides. The reaction products are then separated and quantified by high-performance liquid chromatography coupled to a fluorescence detector at the excitation wavelength 335nm and the emission wavelength 528nm. The retention times for farnesyl–peptide and geranylgeranyl–peptide are 8.4 and 16.9min, respectively. The lower limit of detection is 5pg of FPP or GGPP (∼0.01pmol). A linear response has been established over a range of 5–1000pg (∼0.01–2pmol) with good reproducibility. The method has been used to determine the levels of FPP (0.125±0.010pmol/106cells) and GGPP (0.145±0.008pmol/106cells) in NIH3T3 cells. Furthermore, changes in FPP and GGPP levels following treatment of cells with isoprenoid biosynthetic pathway inhibitors were measured. This method is suitable for the determination of the concentrations of FPP and GGPP in any cell type or tissue. [Copyright &y& Elsevier]

The isoprenoids farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP) are synthetic precursors for numerous molecules essential for cellular function as well as substrates in isoprenylation reactions. We have previously demonstrated that depletion of mevalonate results in the upregulation of Ras-related proteins which can be prevented by FPP or GGPP, independent of restoration of protein isoprenylation. To better define the regulatory properties of isoprenoid pyrophosphates, we have investigated the abilities of isoprenoid analogues to regulate the expression of the Ras-related proteins. Farnesyl phosphonic acids potentiate the upregulation of these proteins induced by mevalonate depletion independent of inhibitory activity against farnesyl protein transferase, geranylgeranyl protein transferase I, FPP synthase, or GGPP synthase. The potentiation of RhoB upregulation is at both the mRNA and protein level. The ability of these analogues to serve as functional antagonists of the isoprenoid pyrophosphates is dependent on the nature of the functional group at the head of the molecule, the charge of the molecule, and the length of the isoprenoid chain. Metabolites and additional analogues of isoprenoid pyrophosphates were found to possess agonist properties relative to FPP and GGPP. Interestingly, the structurally related retinoids all-trans-retinoic acid and 9-cis-retinoic acid also display slight agonist properties. These studies provide evidence for direct roles of FPP and GGPP in regulating transcriptional and post-transcriptional events. [ABSTRACT FROM AUTHOR]

Mevalonate depletion by inhibition of hydroxymethylglutaryl coenzyme A reductase impairs post-translational processing of Ras and Ras-related proteins. We have previously shown that this mevalonate depletion also leads to the upregulation of Ras, Rap1a, RhoA, and RhoB. This upregulation may result from global inhibition of isoprenylation or depletion of key regulatory isoprenoid species. Studies utilizing specific isoprenoid pyrophosphates in mevalonate-depleted cells reveal that farnesyl pyrophosphate (FPP) restores Ras processing and prevents RhoB upregulation while geranylgeranyl pyrophosphate (GGPP) restores Rapla processing and prevents RhoA and RhoB upregulation. Either FPP or GGPP completely prevents lovastatin-induced upregulation of RhoB mRNA. Inhibition of FPP or squalene synthase allowed for the further identification of the putative regulatory species. Studies involving the specific isoprenyl transferase inhibitors FTI-277 and GGTI-286 demonstrate that selective inhibition of protein isoprenylation does not mimic lovastatin's ability to increase Ras and RhoA synthesis, decrease Ras and RhoA degradation, increase RhoB mRNA, or increase total levels of Ras, Rapla, RhoA, and RhoB. In aggregate, these findings reveal a novel role and mechanism for isoprenoids to influence levels of Ras and Ras-related proteins. [ABSTRACT FROM AUTHOR]

Autologous stem cell transplantation (ASCT) has been a backbone of therapy for newly diagnosed patients with multiple myeloma eligible for high-dose therapy for decades. Survival outcomes have continued to improve over time, in part because of the incorporation of highly effective induction regimens prior to ASCT as well as post-ASCT maintenance therapy. Randomized phase III clinical trials have helped establish lenalidomide maintenance as a standard of care. However, as nearly all patients will eventually experience disease relapse, there continues to be significant interest in developing novel maintenance strategies to improve upon lenalidomide maintenance. In this review, we summarize the available evidence for the use of immunomodulatory drugs, proteasome inhibitors, and monoclonal antibodies as post-ASCT maintenance therapies as well as discuss future directions and unanswered questions in the field. [ABSTRACT FROM AUTHOR]

Summary: Due in part to racial disparities and underrepresentation in clinical studies, optimal therapies for Black patients with multiple myeloma remain undefined. This final analysis of GRIFFIN by race showed that the addition of daratumumab (D) to lenalidomide/bortezomib/dexamethasone (RVd) provides clinical benefit among both Black and White transplant‐eligible newly diagnosed patients compared with RVd alone. However, Black patients were more likely to discontinue ≥1 drug due to treatment‐emergent adverse events. In summary, these findings suggest a benefit of D‐RVd front‐line therapy among Black and White patients and underscore the importance of equitable treatment access for all patients. [ABSTRACT FROM AUTHOR]

Purpose: To investigate ophthalmic onset manifestations and the impact of diagnostic delay on the prognosis in infants (<1 year) diagnosed with a brain tumour. Methods: A retrospective population‐based nationwide study of infants diagnosed with a brain tumour between 2007 and 2017 in Denmark. Data was retrieved from the Danish Childhood Cancer Registry, the National Danish Health registries, and medical files. Primary outcome measures included symptoms, clinical findings, time to diagnosis and survival. Results: Thirty‐seven infants were diagnosed with a brain tumour in Denmark between 2007 and 2017. In total, 19/37 infants (51%, 95% CI: 34–68) had ophthalmic manifestations at any time prior to or at diagnosis; and in 6/37 (16%, 95% CI: 6–32) ophthalmic manifestations were the initial symptom. The most common ophthalmic manifestations were strabismus (n = 7), sunset eyes (n = 6), nystagmus (n = 4), reduced pupillary light reflex (n = 4), and/or decreased vision (n = 4). The median number of symptoms per infant at the time of diagnosis was three (range 0–9). The median diagnostic delay was 26 days (range 0–283, IQR: 6;90). 5‐year survival rate was 75% (95% CI: 61–90) and all children with diagnostic delay > 100 days (n = 9, 24%) were still alive at the end of follow‐up (median 6.3 years, range 2.2–10.2). Conclusion: We provide an overview of symptoms and clinical signs in a nation‐wide series of infants with CNS tumours and demonstrate that ophthalmic manifestations are frequently observed in infants prior to diagnosis, but, often in combination with other clinical signs. The diagnostic delay was substantial for a large part of the infants, but this was not associated with increased mortality. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is a primary malignant bone tumor characterized by frequent metastasis, rapid disease progression, and a high rate of mortality. Treatment options for OS have remained largely unchanged for decades, consisting primarily of cytotoxic chemotherapy and surgery, thus necessitating the urgent need for novel therapies. Tropolones are naturally occurring seven‐membered non‐benzenoid aromatic compounds that possess antiproliferative effects in a wide array of cancer cell types. MO‐OH‐Nap is an α‐substituted tropolone that has activity as an iron chelator. Here, we demonstrate that MO‐OH‐Nap activates all three arms of the unfolded protein response (UPR) pathway and induces apoptosis in a panel of human OS cell lines. Co‐incubation with ferric chloride or ammonium ferrous sulfate completely prevents the induction of apoptotic and UPR markers in MO‐OH‐Nap‐treated OS cells. MO‐OH‐Nap upregulates transferrin receptor 1 (TFR1) protein levels, as well as TFR1, divalent metal transporter 1 (DMT1), iron‐regulatory proteins (IRP1, IRP2), ferroportin (FPN), and zinc transporter 14 (ZIP14) transcript levels, demonstrating the impact of MO‐OH‐Nap on iron‐homeostasis pathways in OS cells. Furthermore, MO‐OH‐Nap treatment restricts the migration and invasion of OS cells in vitro. Lastly, metabolomic profiling of MO‐OH‐Nap‐treated OS cells revealed distinct changes in purine and pyrimidine metabolism. Collectively, we demonstrate that MO‐OH‐Nap‐induced cytotoxic effects in OS cells are dependent on the tropolone's ability to alter cellular iron availability and that this agent exploits key metabolic pathways. These studies support further evaluation of MO‐OH‐Nap as a novel treatment for OS. [ABSTRACT FROM AUTHOR]

A letter to the editor on granular cell tumor in eye is presented.

Rab GTPases are critical regulators of protein trafficking in the cell. To ensure proper cellular localization and function, Rab proteins must undergo a posttranslational modification, termed geranylgeranylation. In the isoprenoid biosynthesis pathway, the enzyme geranylgeranyl diphosphate synthase (GGDPS) generates the 20‐carbon isoprenoid donor (geranylgeranyl pyrophosphate [GGPP]), which is utilized in the prenylation of Rab proteins. We have pursued the development of GGDPS inhibitors (GGSI) as a novel means to target Rab activity in cancer cells. Osteosarcoma (OS) and Ewing sarcoma (ES) are aggressive childhood bone cancers with stagnant survival statistics and limited treatment options. Here we show that GGSI treatment induces markers of the unfolded protein response (UPR) and triggers apoptotic cell death in a variety of OS and ES cell lines. Confirmation that these effects were secondary to cellular depletion of GGPP and disruption of Rab geranylgeranylation was confirmed via experiments using exogenous GGPP or specific geranylgeranyl transferase inhibitors. Furthermore, GGSI treatment disrupts cellular migration and invasion in vitro. Metabolomic profiles of OS and ES cell lines identify distinct changes in purine metabolism in GGSI‐treated cells. Lastly, we demonstrate that GGSI treatment slows tumor growth in a mouse model of ES. Collectively, these studies support further development of GGSIs as a novel treatment for OS and ES. [ABSTRACT FROM AUTHOR]

Tropolones, such as β-thujaplicin, are small lead-like natural products that possess a variety of biological activities. While the β-substituted natural products and their synthetic analogs are potent inhibitors of human cancer cell growth, less is known about their α-substituted counterparts. Recently, we synthesized a series of α-substituted tropolones including 2-hydroxy-7-(naphthalen-2-yl)cyclohepta-2,4,6-trien-1-one (α-naphthyl tropolone). Here, we evaluate the antiproliferative mechanisms of α-naphthyl tropolone and the related α-benzodioxinyl analog. The α-substituted tropolones inhibit growth of lymphocytic leukemia cells, but not healthy blood cells, with nanomolar potency. Treatment of leukemia cell lines with the tropolone dose-dependently induces apoptosis as judged by staining with annexin V and propidium iodide and Western blot analysis of cleaved caspase 3 and 7. Moreover, pre-treatment of cells with the caspase inhibitor Z-VAD-FMK inhibited the apoptotic effects of the tropolone in two lymphocytic lines. Caspase inhibition also blocked elevated histone acetylation caused by the tropolone, indicating that its effects on histone acetylation are potentiated by caspases. In contrast, α-naphthyl tropolone upregulated p53 expression and phosphorylation of Akt and mTOR in a manner that was not rescued by caspase inhibition. The effects of tropolone were blocked by co-incubation with high levels of free extracellular iron but not by pre-loading with iron. Additionally, dose and time dependent reduction in ex vivo viability of cells from leukemia patients was observed. Taken together, we demonstrate that α-substituted tropolones upregulate DNA damage repair pathways leading to caspase-dependent apoptosis in malignant lymphocytes. [ABSTRACT FROM AUTHOR]

The enzyme geranylgeranyl diphosphate synthase (GGDPS) is believed to receive the substrate farnesyl diphosphate through one lipophilic channel and release the product geranylgeranyl diphosphate through another. Bisphosphonates with two isoprenoid chains positioned on the α-carbon have proven to be effective inhibitors of this enzyme. Now a new motif has been prepared with one isoprenoid chain on the α-carbon, a second included as a phosphonate ester, and the potential for a third at the α-carbon. The pivaloyloxymethyl prodrugs of several compounds based on this motif have been prepared and the resulting compounds have been tested for their ability to disrupt protein geranylgeranylation and induce cytotoxicity in myeloma cells. The initial biological studies reveal activity consistent with GGDPS inhibition, and demonstrate a structure–function relationship which is dependent on the nature of the alkyl group at the α-carbon. [ABSTRACT FROM AUTHOR]

Summary: Patients with multiple myeloma are at increased risk of vascular thromboembolic events (VTEs). This post hoc analysis evaluated VTEs in the randomised phase 2 GRIFFIN study (ClinicalTrials.gov Identifier: NCT02874742) that investigated lenalidomide/bortezomib/dexamethasone (RVd) ± daratumumab (D). Patients with newly diagnosed multiple myeloma who were eligible for autologous stem cell transplantation (ASCT) received D‐RVd/RVd induction, high‐dose therapy and ASCT, D‐RVd/RVd consolidation and up to 2 years of lenalidomide maintenance therapy ± D. VTE prophylaxis was recommended (at least aspirin, ≥162 mg daily) in accordance with International Myeloma Working Group guidelines. In the safety population (D‐RVd, n = 99; RVd, n = 102), VTEs occurred in 10.1% of D‐RVd patients and 15.7% of RVd patients; grade 2–4 VTEs occurred in 9.1% and 14.7%, respectively. Median time to the first onset of VTE was longer for D‐RVd versus RVd patients (305 days vs 119 days). Anti‐thrombosis prophylaxis use was similar between arms (D‐RVd, 84.8% vs RVd, 83.3%); among patients with VTEs, prophylaxis use at time of first VTE onset was 60.0% for D‐RVd and 68.8% for RVd. In summary, the addition of daratumumab to RVd did not increase the incidence of VTEs, but the cumulative VTE incidence was relatively high in this cohort and anti‐thrombotic prophylaxis use was suboptimal. [ABSTRACT FROM AUTHOR]