INT-1B3, an LNP formulated miR-193a-3p mimic, promotes anti-tumor immunity by enhancing T cell mediated immune responses via modulation of the tumor microenvironment and induction of immunogenic cell death.

microRNAs (miRNAs) are small, non-coding RNAs that regulate expression of multiple genes. MiR-193a-3p functions as a tumor suppressor in many cancer types, but its effect on inducing specific anti-tumor immune responses is unclear. Therefore, we examined the effect of our lipid nanoparticle (LNP) formulated, chemically modified, synthetic miR-193a-3p mimic (INT-1B3) on anti-tumor immunity. INT-1B3 inhibited distant tumor metastasis and significantly prolonged survival. INT-1B3-treated animals were fully protected against challenge with autologous tumor cells even in absence of treatment indicating long-term immunization. Protection against autologous tumor cell challenge was hampered upon T cell depletion and adoptive T cell transfer abrogated tumor growth. Transfection of tumor cells with our miR-193a-3p mimic (1B3) resulted in tumor cell death and apoptosis accompanied by increased expression of DAMPs. Co-culture of 1B3-transfected tumor cells and immature DC led to DC maturation and these mature DC were able to stimulate production of type 1 cytokines by CD4+ and CD8+ T cells. CD4-CD8- T cells also produced type 1 cytokines, even in response to 1B3-transfected tumor cells directly. Live cell imaging demonstrated PBMC-mediated cytotoxicity against 1B3-transfected tumor cells. These data demonstrate for the first time that miR-193a-3p induces long-term immunity against tumor development via modulation of the tumor microenvironment and induction of immunogenic cell death.

Multi-modal effects of 1B3, a novel synthetic miR-193a-3p mimic, support strong potential for therapeutic intervention in oncology.

Compelling evidence demonstrates that miR-193a-3p is a tumor suppressor microRNA in many cancer types, and its reduced expression is linked to cancer initiation and progression, metastasis, and therapy resistance. However, its mechanism of action is not consistently described between studies, and often contradicts the pleiotropic role of a microRNA in manipulating several different mRNA targets. We therefore comprehensively investigated miRNA-193a-3p's mode of action in a panel of human cancer cell lines, with a variety of genetic backgrounds, using 1B3, a synthetic microRNA mimic. Interestingly, the exact mechanism through which 1B3 reduced cell proliferation varied between cell lines. 1B3 efficiently reduced target gene expression, leading to reduced cell proliferation/survival, cell cycle arrest, induction of apoptosis, increased cell senescence, DNA damage, and inhibition of migration. SiRNA silencing of 1B3 target mRNAs further highlighted the advantage of the pleiotropic mechanism of 1B3 action, as repression of individual targets did not achieve the same robust effect on cell proliferation in all cell lines. Importantly, a novel lipid nanoparticle-based formulation of 1B3, INT-1B3, demonstrated marked anti-tumor activity as a single agent following systemic administration in tumor-bearing mice. Together, these data strongly support the development of 1B3 as a novel therapeutic agent for treatment of human cancer.

Transcriptome-wide analysis reveals insight into tumor suppressor functions of 1B3, a novel synthetic miR-193a-3p mimic.

Emerging data show that microRNA 193a-3p (miR-193a-3p) has a suppressive role in many cancers and is often downregulated in tumors, as compared to surrounding normal tissues. Therefore, mimics of miR-193a-3p could be used as an attractive therapeutic approach in oncology. To better understand and document the molecular mechanism of action of 1B3, a novel synthetic miRNA-193a-3p mimic, RNA sequencing was performed after transfection of 1B3 in six different human tumor cell lines. Genes differentially expressed (DE) in at least three cell lines were mapped by Ingenuity Pathway Analysis (IPA), and interestingly, these results strongly indicated upregulation of the tumor-suppressive phosphatase and tensin homolog (PTEN) pathway, as well as downregulation of many oncogenic growth factor signaling pathways. Importantly, although unsurprisingly, IPA identified miR-193a-3p as a strong upstream regulator of DE genes in an unbiased manner. Furthermore, biological function analysis pointed to an extensive link of 1B3 with cancer, via expected effects on tumor cell survival, proliferation, migration, and cell death. Our data strongly suggest that miR-193a-3p/1B3 is a potent tumor suppressor agent that targets various key oncogenic pathways across cancer types. Therefore, the introduction of 1B3 into tumor cells may represent a promising strategy for cancer treatment.

The use of medical care and the prevalence of serious illness in an adult Prader-Willi syndrome cohort.

INTRODUCTION: Adults with Prader-Willi syndrome (PWS) have an increased occurrence of several medical conditions. We report on the consequences of high morbidity rates such as prevalence rate of hospital admissions, medication use and surgery in a Dutch cohort of adults with PWS. Special attention is paid to causes and symptoms of serious illness. METHOD: Participants were contacted via the Dutch Prader-Willi Parent Association and through physicians specializing in persons with ID. The persons with PWS and their main caregivers were visited at home. Information was collected through semi-structured interviews on 102 adults with PWS. RESULTS: The need for medical care in the neonatal period is associated with hypotonia and feeding problems. Hospital admissions for respiratory tract infections are frequent. During childhood most hospital admissions were due to PWS syndrome specific surgery. During adolescence hospital admissions occurred for scoliosis surgery and endocrine evaluations. At adult age, hospitalization was associated with inguinal hernia surgery, diabetes mellitus, psychosis, erysipelas, water and drug intoxications. In the older group, respiratory infections were again the main reason for hospital admissions. Frequently used medications at adult age included psychotropics, laxatives, anti-diabetics and dermatologic preparations. Abnormal drinking patterns, problems with anesthesia, decreased ability to vomit, abnormal pain awareness and unpredictable fever responses were frequent and often lead to delayed diagnoses of serious conditions. DISCUSSION: People with PWS are frequent users of medical-care. Reasons for hospitalization and medication use are age specific. Knowledge on the different presentation of symptoms in people with PWS is needed. In case of unexplained illness, disturbances of consciousness and behavioral changes in people with PWS, an infection should be ruled out in the first place. Information from this study may help in preventing conditions and recognizing conditions in an early stage. Adequate preventive management and treatment of PWS related morbidity, could reduce medical care use in the long term and could improve quality adjusted life years.

Behavioral phenotype in adults with Prader-Willi syndrome.

Prader-Willi syndrome (PWS) is characterized by temper tantrums, impulsivity, mood fluctuations, difficulty with change in routine, skinpicking, stubbornness and aggression. Many studies on behavior in PWS are limited by sample size, age range, a lack of genetically confirmed diagnosis of PWS and inconsistent assessment of behavior. The aim of this study was to explore systematically the relation between behavioral problems and age groups, genetic subtypes and BMI categories in an adult PWS population. Participants were contacted via the Dutch Prader-Willi Parent Association and through physicians specialized in persons with ID. Behaviors were studied using the Developmental Behavior Checklist for Adults (DBC-A). The forms were completed by the main caregivers of 98 adults with a genetically confirmed diagnosis of PWS. Differences between age groups were statistically significant (ANOVA, p=0.03). DBC-A total scores were higher in the consecutive age groups, with the most behavioral problems in the oldest age groups. Differences between genetic subtypes were also statistically significant (ANOVA, p<0.01). Persons with mUPD had higher total scores on the DBC-A than persons with a deletion. Those with a Type I deletion showed higher total DBC-A scores than persons with a Type II deletion. There were no statistically significant differences in DBC-A total scores between the different BMI categories. Individuals with a BMI<25 had higher scores on the self-absorbed subscale compared to persons with a BMI between 25 and 30. Unlike previous descriptions of the behavioral phenotype in adults with PWS, we did not find a reduction in behavioral problems in older adults. Therefore, special attention should be paid to behavioral problems as part of general management of adults with PWS. Longitudinal studies are warranted to gain more insight into the natural history and course of behavioral problems in adults and older people with PWS over the long term and possible risk and preventive factors.

Analysis of candidate imprinted genes in PWS subjects with atypical genetics: a possible inactivating mutation in the SNURF/SNRPN minimal promoter.

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder associated with abnormalities of chromosome 15q11q13. The majority of cases result either from a deletion approximately 4 Mb in size, affecting chromosome 15 of paternal origin or from UPD(15)mat; these account for approximately 70 and approximately 20-25% of PWS cases, respectively. In the remaining 3-5% of PWS cases where neither the deletion nor UPD is detectable, PWS is thought to be caused either by a defect in the imprinting centre resulting in a failure to reset the paternally inherited chromosome 15 derived from the paternal grandmother or, very occasionally, from a balanced translocation involving a breakpoint in 15q11q13. Nine probands with a firm clinical diagnosis of PWS but who had neither a typical deletion in the PWS region nor UPD(15)mat were investigated for inactivating mutations in 11 genes located in the PWS region, including SNURF and SNRPN, which are associated with the imprinting centre. Other genes studied for mutations included MKRN3, NDN, IPW, HBII-85, HBII-13, HBII-436, HBII-438a, PAR1 and PAR5. A possibly inactivating mutation in the SNRPN minimal promoter region was identified. No other inactivating mutations were found in the remainder of our panel of PWS subjects with atypical genetics. Expression levels of several of the candidate genes for PWS were also investigated in this series of probands. The results indicate that PWS may result from a stochastic partial inactivation of important genes.