Associations between IL-1α, IL-1ß, TNFα, and IL-6 variations, and susceptibility to transposition of the great arteries.

BACKGROUND: To evaluate the relationship between IL-1α -889C/T (rs1800587), IL-1ß -511C > T (rs16944), TNFα -308G > A (rs1800629), TNFα -238G > A (rs361525), IL-6 -174G > C (rs1800795), and IL-6 -572G > C (rs1800796) polymorphisms and the susceptibility to transposition of the great arteries (TGA). METHODS: A prospective analysis was performed on mothers whose newborns were diagnosed as having TGA. For each case of TGA, a mother who gave birth to a healthy neonate in the same period was randomly selected for the control group. The sample size was calculated before planning the study with 80% power and 5% alpha. RESULTS: Twenty-seven mothers whose newborn had TGA anomalies (group 1) and 27 mothers whose newborn had no TGA (group 2) were included in the study. There were no significant differences between the groups in terms of maternal age, pregestational body mass index, gestational age at birth and infant sex (p > 0.05). The genotype and allele distributions of IL-1α -889C/T (rs1800587), IL-1ß -511C > T (rs16944), TNFα -308G > A (rs1800629), TNFα -238G > A (rs361525), IL-6 -174G > C (rs1800795) and IL-6 -572G > C (rs1800796) gene variants were not different between the two groups (p > 0.05). CONCLUSIONS: There was no relation between IL-1α, IL-1ß, IL-6, and TNFα promoter gene polymorphisms and TGA occurrence in our study group. TRIAL REGISTRATION: This present prospective case-control study was conducted in Baskent University Hospital, Ankara, Turkey, between May 2020 and November 2021. Ethical approval was obtained from the university's Clinical Research Ethics Commitee (No: KA20/211) in accordance with the Declaration of Helsinki.

Biochemical, radiologic, ultrastructural, and genetic evaluation of iron overload in acute leukemia and iron-chelation therapy.

Iron overload in hereditary hemochromatosis and hematologic malignancy has unfavorable effects on morbidity. Herein, 53 children (age 108.4±58.3 mo, 25 girls and 28 boys) with acute myeloblastic and lymphoblastic leukemia, who received 4 different chemotherapy protocols, were evaluated for iron overload throughout chemotherapy. Iron overload arose: (1) before chemotherapy, which was dependent on neither chemotherapy nor packed red blood cell transfusions and (2) after chemotherapy, which was dependent on the duration and nature of chemotherapy and partially on transfusion of packed red blood cells. Iron overload was documented in 75% of patients with a ferritin level >1000 ng/mL, by liver and heart magnetic resonance imaging, and they were administered iron-chelation therapy with success. Three of 10 radiologically iron-overloaded patients were heterozygous for H63D mutation. Aminolevulinic acid and porphobilinogen levels were normal. Light microscopic examination of the bone marrow revealed increased iron granules in erythroblasts, platelets, and megakaryocytes, iron-laden macrophages, free iron in the matrix, dyshematopoiesis, and apoptotic cells. Electron microscopic examination revealed iron-laden secondary lysosomes and autolysosomes in normoblasts and iron-laden primary granules in promyelocytes, irrelevant to the ferritin level, implying autophagia due to chemotherapy as a source of the excess iron. We think that iron overload, which is an important complication of acute leukemia, should be evaluated separately from "transfusion overload," and the management principles specific to leukemia should be implemented.

Fractalkine receptor polymorphism and chronic tonsillitis.

The objective of this study is to examine whether there is an association of fractalkine gene receptor polymorphisms with chronic tonsillitis. This is a cross-sectional study in the setting of a tertiary referral center. The study group included 79 patients with chronic tonsillitis and 76 controls without history of chronic tonsillitis. Genotypes were identified by restriction fragment length polymorphism analyses after polymerase chain reaction. c.745G>A (V249I) single nucleotide polymorphism and the frequencies of the G and A alleles did not differ in the patient and control groups (p = 0.363; p = 0.743, respectively). c.839C>T (T280M) single nucleotide polymorphism was found to be higher in controls than in the patients with chronic tonsillitis (p < 0.001). Consistent with this result, T allele frequency was higher in controls than in the patients with chronic tonsillitis (p < 0.001). In this study, we suggested that fractalkine gene receptor c.839C>T (T280M) single nucleotide polymorphism could be associated with a reduced risk of chronic tonsillitis.

beta-Adrenoreceptor antagonists reduce cancer cell proliferation, invasion, and migration.

CONTEXT: Propranolol, atenolol, and ICI118,551 are non-selective ß-adrenergic receptor (AR), ß1-AR, and ß2-AR antagonists, respectively. OBJECTIVE: We investigated the efficacy of propranolol, atenolol, and ICI118,551 on proliferation, migration, and invasion of non-stimulated breast (MCF7), colon (HT-29), and hepatocellular (HepG2) cancer cells. MATERIALS AND METHODS: ß-AR expression profiling of cells was performed by real time PCR. Cell proliferation was determined by MTT. Boyden chamber and scratch assays were performed to evaluate invasion and migration. RESULTS AND DISCUSSION: All cell lines expressed ß-ARs. ICI118,551 was the most cytotoxic, whereas atenolol was the least effective ß-AR antagonist for 24, 48, and 72 h. Cell invasion was inhibited by ICI118,551 (45, 46, and 50% for MCF7, HT29, and HepG2, respectively) and propranolol (72, 65, and 90% for MCF7, HT29, and HepG2, respectively). Propranolol, atenolol, and ICI118,551 reduced migration of MCF7, HT-29, and HepG2 cells to varying extents depending on the application concentration and duration. Propranolol and atenolol reduced migration of MCF7 and HT-29 in a concentration-dependent manner, whereas migration of these cells decreased after 48 and 72 h of ICI118,551 applications. CONCLUSION: Beta2-AR antagonist seemed to be the most cytotoxic ß-blocker on non-stimulated cancer cells. Propranolol and ICI118,551 were more effective than atenolol in inhibiting invasion and migration of non-stimulated MCF7 and HT-29 cells; ICI118,551 being the most potent. Concordantly, ß2-selective blockage seemed to be more effective for non-stimulated cells. Effect of the selective ß-AR antagonists showed variation depending on the concentration, incubation time, and histological origin of cells.

Determination of the Frequency of BCL-2 Polymorphisms (c.-717C>A and c.*2364G>A) and LIF Polymorphism (c.*1414T>G) in Patients with Congenital Anomalies of the Kidney and Urinary Tract.

Introduction: Congenital anomalies of the kidney and urinary tract (CAKUT) are characterized by several malformations. Its prevalence is 0.3-0.6% in live births. The B-cell lymphoma (BCL-2) gene regulates apoptosis, and the Leukemia Inhibitory Factor (LIF) gene plays a role in many biological processes, such as blastocyst growth and uterine preparation for implantation. In this study, two single nucleotide polymorphisms (SNPs) of the BCL-2 gene (rs2279115 and rs4987856) and one SNP of the LIF gene (rs929271) were investigated in CAKUT patients for the first time. Methods: Hundred and twenty-nine CAKUT patients and 105 controls were enrolled in this study. We used polymerase chain reaction-restriction fragment length polymorphism for rs2279115 and rs929271 and SNaPshot for rs4987856. The χ2 test was used to compare discrete variables, and the independent sample t test was used to compare continuous variables. Results: The allele frequencies for the rs2279115 and rs4987856 polymorphisms of BCL-2 and the rs929271 polymorphism of LIF were not significantly different between the patient and control groups (p = 0.162, p = 0.053, p = 0.635, respectively). However, the co-segregation analysis revealed a significant difference in the distribution of allele frequencies between the patient and control groups for two genetic variations: LIF rs929271 SNP and BCL-2 rs4987856 SNP (p = 0.034). The relative odds ratio was 2.444 (95% Confidence Interval (CI) 1.054-5.671). Conclusion: This study, which is the first time in the literature, showed that changes in BCL-2 and LIF genes are associated with CAKUT disease.

The impact of developmental genes in non-syndromic cleft lip and/or palate

Non-syndromic cleft lip and/or palate (NSCL/P) is a congenital malformation with a prevalence of 1:700 births. It has a multifactorial etiology. Human craniofacial development takes place during the first 10 weeks of pregnancy. Normal craniofacial development arises from the convergence and fusion of the facial and palatal processes and involves interactions between genes that regulate cell growth, proliferation, differentiation, epithelial-to-mesenchymal transition, and apoptosis. Whole genome/exome analysis, and also genome-wide association studies give us to chance to identify the genetic factors which contribute to the development of NSCL/P. After detecting a cleft lip and/or palate on ultrasonography without associated anomalies, the patient should be evaluated in collaboration with a clinical geneticist, taking into account the many genes and environmental factors involved in NSCL/P etiopathogenesis, and a roadmap for possible genetic diagnosis should be drawn.

Impact of Matrix Metalloproteinases 2 and 9 and Tissue Inhibitor of Metalloproteinase 2 Gene Polymorphisms on Allograft Rejection in Pediatric Renal Transplant Recipients.

OBJECTIVES: Acute and chronic allograft rejection have been continuously an important obstacle in the follow-up of renal transplant recipients. During clinical management, several factors acting simultaneously result in acute rejection and chronic allograft nephropathy. Matrix metalloproteinases and tissue inhibitors of metalloproteinases are responsible for the organization of the extracellular matrix and play roles in cell proliferation and cellular invasion. Changes in matrix metalloproteinase expression levels have been reported to be associated with renal allograft rejection and interstitial fibrosis. In this study, we aimed to investigate functional polymorphisms of MMP2, MMP9, and TIMP2 genes in pediatric renal transplant recipients. MATERIALS AND METHODS: Our study included 68 kidney transplant recipients and 58 control patients. The kidney transplant recipient group was further divided into 2 subgroups: no graft rejection (n = 47) and graft rejection (n =21). MMP2 -735C >T (rs2285053), MMP2 -1306C >T (rs243865), MMP2 -1575G >A (rs243866), MMP9 c.-1562C >T (rs3918242), TIMP2 -418G >C (rs8179090), and TIMP2 303C > T (rs2277698) polymorphisms were analyzed with the use of polymerase chain reaction and restriction fragment-length polymorphism methods. Allele prevalence was compared with reference values of the control group, and Hardy-Weinberg equilibrium was tested. RESULTS: Mean ages were 16.7 ± 3.9 years for the study group and 14.8 ± 5.6 years for the control group. The mean follow-up time after transplant was 37.7 ± 7.9 months. We compared allele frequencies in the 2 groups and calculated a statistically significant difference in rs2285053, rs243865, rs243866, rs3918242, rs8179090, and rs2277698 polymorphism frequencies between the transplant recipients and control patients. When the transplant recipient group was compared in itself with regard to allograft rejection, all investigated polymorphisms except TIMP2 -418G >C (rs8179090) revealed a statistically significant difference between those with and without rejection (P < .05). CONCLUSIONS: Matrix metalloproteinases and their tissue inhibitors could be important predictive biological markers for the follow-up of kidney transplant recipients.

Absence of exon 17 c.2970-2872delAAT mutation in Turkish NF1 patients with mild phenotype.

INTRODUCTION: Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterized by café-au-lait spots, neurofibromas, skinfold freckles, Lisch nodules, bone deformities, learning disabilities, and predisposition to neoplasms. It is caused by various mutations of the NF1 gene. Recently a 3-bp in-frame deletion in exon 17, c.2970-2972 delAAT mutation, has been associated with a milder phenotype of NF1 manifesting with pigmentary skin changes only. MATERIALS AND METHODS: We therefore analyzed 35 NF1 patients without neurofibromas, learning problems, or bone lesions (19 familial, 16 sporadic, age 7-44 years) for exon 17 mutations by DNA sequencing. RESULTS: We did not find the c.2970-2972 delAAT mutation in this group but identified two base changes in exon 17 (c.2989A>G and c.2894T>A), whether these two novel mutations are related to a mild phenotype remains to be confirmed in further studies. Our results suggest the reported phenotypic associations may not be valid for all populations.

Learning disability and oligodendrocyte myelin glycoprotein (OMGP) gene in neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is an autosomal dominant disease where phenotypic heterogeneity is explained by the effect of modifier genes. Thirty to 65% of patients have learning disability. The oligodendrocyte myelin glycoprotein (OMGP) gene located within the neurofibromatosis type 1 (NF1) gene might affect the phenotype of learning disability because it is expressed in the brain, and OMGP gene mutations have been associated with cognitive disturbances. We analyzed the OMGP gene in NF1 patients with and without learning disability (n = 50 each) and healthy controls (n = 100). The allele distribution of OMGP62 polymorphism was not significantly different between the groups (p = 0.447). These results do not support a relationship between the OMGP gene and the learning disability phenotype observed in NF1. Other modifying genes, post-translational modifications or receptor interactions might be involved in the phenotypic variability of NF1.

Persistent Hyperinsulinemic Hypoglycemia with Pancreatic Teratoma in Infancy: A Case Report.

BACKGROUND Pediatric intraabdominal pancreatic teratomas have been rarely reported. This is the first case of severe hyperinsulinemic hypoglycemia in a 6-month-old infant secondary to an intraabdominal teratoma. The hypoglycemia resolved after surgical removal. CASE REPORT A 6-month-old infant was seen in a pediatric emergency department with complaints of lethargy and abnormal eye movements. She was diagnosed with hyperinsulinemic hypoglycemia and started on diazoxide. A CT and MRI of the abdomen revealed a 165×77×72 mm cyst with a 51×45×30 mm solid structure connecting to the wall of the cyst by a stalk, raising suspicion of a fetus in fetu. The mass had no connection to her pancreas. Following total excision of the intraabdominal mass, her hypoglycemia resolved. Histopathological examination showed immature fetal pancreatic tissue consistent with a mature teratoma. Whole exon sequencing of the infant's peripheral blood showed a negative mutation of ABCC8 and presence of heterozygous variations of HNF1ß and IRS1 genes. CONCLUSIONS This is the first case report of an infant with severe hyperinsulinemic hypoglycemia secondary to a pancreatic teratoma. The heterozygous variations of HNF1ß and IRS1 genes likely played a role in the embryogenesis, causing a pancreatic teratoma and hyperinsulinemic hypoglycemia.

The differences in the expression of fractalkine and its receptor in conditions of tonsillar hypertrophy and chronic tonsillitis.

OBJECTIVE: Fractalkine, member of chemokine family, is involved in many inflammatory processes in the human body. The aim of this study is to compare expression levels of fractalkine ligand and its receptor in chronic tonsillitis and hypertrophic tonsil samples. METHODS: The study was conducted at Baskent University Departments of Otorhinolaryngology and Medical Genetics. It is designed as a prospective, non-randomized, controlled clinical study. Total 97 samples, obtained from adenotonsillectomy due to chronic tonsillitis or tonsillar hypertrophy, were participated in the study. Fractalkine and its receptor expression levels were determined and comparison was made between the tissue groups. c.839C>T (T280M) polymorphism of fractalkine receptor was analyzed, then relationship between polymorphism and the expression level of fractalkine receptor was investigated. RESULTS: Fractalkine receptor expression was significantly higher in the hypertrophic tonsil group than chronic tonsillitis group (p<0.05). CONCLUSION: Fractalkine, member of chemokine family, and its receptor may play role in preventing chronic-recurrent tonsillitis.

Vitamin D receptor gene TaqI single nucleotide polymorphism is not associated with lead levels in maternal and umbilical cord blood.

PURPOSE: We aimed to investigate the association of vitamin D receptor (VDR) gene TaqI single nucleotide polymorphism (SNPs) with serum lead (Pb) levels in maternal and umbilical cord blood. MATERIALS AND METHODS: Eighty-one patients who lived in Konya, Turkey for the last 3 years and had delivery at Baskent University Konya Hospital in 2016 were included in this study. Venous blood samples were drawn from each volunteer immediately before giving birth to determine the maternal Pb levels and VDR SNPs. Additionally, umbilical cord blood samples were collected from the umbilical vein into tube with EDTA as an anticoagulant immediately after birth to determine Pb levels of the fetus. RESULTS: The median level of Pb in the maternal blood was 29.00 (Interquartile Range (IQR) = 16.35) µg/L and the median Pb level in the cord blood was 22.50 (IQR = 9.75) µg/L. Blood Pb level of women living in the urban area was significantly higher than in those living in the rural area (Z = 2.118; p = .034). There was a very strong positive correlation between the Pb levels in the maternal blood and in the umbilical cord blood (ρ = 0.825, p < .001, respectively). Regarding VDR SNPs, "TT", "TC", and "CC" VDR TaqI genotypes were observed in 28 (34.6%), 45 (55.5%), and eight samples (9.9%), respectively. Pb levels in maternal and cord blood were higher in women with the "CC" VDR TaqI genotype; however, there was no statistically significant difference (p > .05). CONCLUSIONS: Although women with the "CC" VDR TaqI genotype had higher maternal and cord blood Pb levels, this was statistically insignificant and therefore, VDR TaqI SNPs did not significantly affect maternal and umbilical cord blood Pb levels.

A highly efficient and faithful MDS patient-derived xenotransplantation model for pre-clinical studies.

Comprehensive preclinical studies of Myelodysplastic Syndromes (MDS) have been elusive due to limited ability of MDS stem cells to engraft current immunodeficient murine hosts. Here we report a MDS patient-derived xenotransplantation model in cytokine-humanized immunodeficient "MISTRG" mice that provides efficient and faithful disease representation across all MDS subtypes. MISTRG MDS patient-derived xenografts (PDX) reproduce patients' dysplastic morphology with multi-lineage representation, including erythro- and megakaryopoiesis. MISTRG MDS-PDX replicate the original sample's genetic complexity and can be propagated via serial transplantation. MISTRG MDS-PDX demonstrate the cytotoxic and differentiation potential of targeted therapeutics providing superior readouts of drug mechanism of action and therapeutic efficacy. Physiologic humanization of the hematopoietic stem cell niche proves critical to MDS stem cell propagation and function in vivo. The MISTRG MDS-PDX model opens novel avenues of research and long-awaited opportunities in MDS research.

Odontogenic effects of two calcium silicate-based biomaterials in human dental pulp cells.

BACKGROUND: The goal of treating exposed pulp with an appropriate pulp capping material is to promote the dentinogenic potential of the pulpal cells. There have been recent attempts to develop more effective pulp-capping materials. OBJECTIVES: The aim of this study was to evaluate the effect of newly developed calcium silicate-based material on odontogenic differentiation of primary human dental pulp cells (HDPCs), in comparison with a contemporary calcium silicate-based material. MATERIAL AND METHODS: Human dental pulp cells isolated from dental pulps were cultured in standard culture conditions in Dulbecco's Modified Eagle's Medium (DMEM) and then the effects of Micro-Mega mineral trioxide aggregate (MM-MTA) (Micro-Mega, Besançon, France) and ProRoot MTA (MTA) (Dentsply Sirona, Tulsa, USA) (positive control) were evaluated on HDPCs at 1, 7 and 14 days. Untreated cells were used as a negative control. Odontoblastic differentiation was assessed by alkaline phosphatase (ALP) activity. Runtrelated transcription factor 2 (RUNX2), alkaline phosphatase liver/bone/kidney (ALPL), bone morphogenetic protein 2 (BMP2), dentin sialophosphoprotein (DSPP), and Distal-less homeobox 3 (DLX3), as odontoblastic/ osteoblastic expression markers, were evaluated by semi-quantitative real-time polymerase chain reaction (RT-PCR) analysis. Calcium levels of culture media were also determined. RESULTS: The MM-MTA group significantly increased the expression of BMP2 compared with that of the MTA group at 3 different time periods (p < 0.05). The up-regulation of ALPL between day 1 and 14 and the up-regulation of DSPP between day 7 and 14 were significant in both groups (p < 0.05). Micro-Mega MTA and MTA exhibited similar messenger RNA (mRNA) expression levels of ALPL, DSPP, RUNX2, DLX3, and ALP activities, as well as calcium levels. CONCLUSIONS: Based on the cell responses observed in this study, MM-MTA might be used efficiently in dental pulp therapy as a potential alternative to MTA.

Neurofibromatosis: novel and recurrent mutations in Turkish patients.

Neurofibromatosis type 1 is an autosomal-dominant disorder affecting approximately 1 in 3500 births. It is characterized by café-au-lait spots, neurofibromas, axillary/inguinal freckling, and skeletal and neurologic signs. It exhibits full penetrance and a high mutation rate: 50% of neurofibromatosis type 1 patients represent a new mutation. The gene, located at 17q11.2, contains 60 exons that encode a 11-13-kb mRNA transcript. The mutation rate for neurofibromatosis type 1 is one of the highest known for human disorders, probably because of the large size of the gene, gene conversions mediated by pseudogenes, and the presence of repeated sequences. No clear genotype-phenotype correlation is established, except for patients with deletion of the entire neurofibromatosis type 1 gene. Neurofibromatosis type 1 mutations seem to be equally distributed along the gene. However, some exons in the neurofibromatosis type 1 gene may have a higher mutation rate, and the majority of these mutations are recurrent. We analyzed five exons (exons 4b, 16, 29, 31, and 37) for recurrent mutations and unknown mutations in 100 Turkish patients with neurofibromatosis type 1. We identified 496delGT and 499delTGTT mutations in exon 4b and 5866delA as a new mutation in exon 31 (Human Gene Mutation Database accession number Hd0524).

Enhancement of vascular endothelial growth factor's angiogenic capacity by the therapeutic modulation of notch signalling improves tram flap survival in rats submitted to nicotine.

BACKGROUND: Smoke of cigarettes, and specifically nicotine, has been shown to diminish pedicled transverse rectus abdominis musculocutaneous (TRAM) flap survival. Considering that Notch signalling through its ligand Delta-like 4 (Dll4) functions as anti-angiogenic factor by inhibiting the pro-angiogenic effects of vascular endothelial growth factor (VEGF), it is hypothesised that inhibition of the Notch would promote angiogenesis and increase TRAM flap survival in rats submitted to nicotine. METHODS: Twenty rats were treated with nicotine for 28 days preoperatively. Thereafter, a pedicled TRAM flap was created in all animals. The Notch inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine-t-butyl-ester was administered in animals of the treatment group. Animals in the control group were given the same amount of solvent. Five days after the surgery, viable flap areas were determined. Skin samples were evaluated for VEGF and Dll4 mRNA levels. Immunohistochemical analysis was used for the assessment of endothelial Dll4 expression. Vascular density was determined histologically. Plasma levels of VEGF and Dll4 were measured. RESULTS: A significant improvement in TRAM flap surviving area was observed in the treatment group (53.50 ± 14.25%) compared with the controls (32.20 ± 9.15%). Immunohistochemical analysis revealed a significant increase in the number of Dll4 stained vessels in animals of the treatment group (9.2 ± 1.6) in comparison with the controls (5.7 ± 1.9). VEGF mRNA levels (0.22 ± 0.08) in the treatment group were significantly lower than those in the control group (0.36 ± 0.09). CONCLUSION: Notch inhibition significantly improved TRAM flap survival in animals exposed to nicotine by promoting VEGF-induced angiogenesis.

The Notch Signaling System Is Involved in the Regulation of Reparative Angiogenesis in the Zone of Stasis.

The Notch pathway ligand Delta-like 4 (Dll4) functions as an antiangiogenic factor, inhibiting vascular endothelial growth factor (VEGF)-induced angiogenesis. This function is documented in tumor and embryonic vasculature. However, its implication in burn wounds remains unexplored. Our objective was to explore the involvement of the Notch in the healing of zone of stasis burns. We hypothesized that anti-Dll4 therapy would prevent progressive necrosis in the stasis zone by promoting angiogenesis. Burns were created in 21 rats using the comb burn model. The Notch inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine-t-butyl-ester was administered in the treatment group. Controls were given the same amount of solvent. Seven days after the burn, skin samples were evaluated for VEGF and Dll4 gene expressions. Immunohistochemical analysis was used for the assessment of vascular density, endothelial Dll4 expression, and apoptosis count. Histologic grading of tissue damage was performed. Circulating levels of VEGF and Dll4 were determined. VEGF and Dll4 mRNA levels were found to be simultaneously induced after the burn. In the treatment group, a significant increase in the number of vessels was observed. However, gross evaluation documented an expansion of necrosis to the zone of stasis with marked activation of apoptosis. Histologic assessment showed that the resultant vascular overgrowth was accompanied by extensive edema and abundant infiltration of leukocytes. We provide evidence for the involvement of Notch in the regulation of angiogenesis in zone of stasis burns.

Two neurofibromatosis type 1 cases associated with rhabdomyosarcoma of bladder, one with a large deletion in the NF1 gene.

Neurofibromatosis type 1 (NF1) is the most common neurogenetic disorder, affecting approximately 1 in 3,500 individuals worldwide. Mutations of the NF1 tumor suppressor gene predispose individuals to a variety of benign and malignant tumors. Rhabdomyosarcoma (RMS) is an uncommon malignant soft tissue sarcoma and is also a rare tumor type in NF1 patients. We report two cases of NF1 with RMS. The first is that of an infant with overlapping phenotypic features of NF1 and Noonan syndrome (NS) who presented with RMS of the bladder. The second infant likewise exhibited NF1 features and was also associated with bladder RMS. DNA samples were extracted from peripheral blood and tumor tissue samples. We performed loss of heterozygosity (LOH) analysis of the NF1 gene by using seven intragenic markers (IVS27AAAT2.1, IVS27EVI-20, IVS27AC24.8, IVS27AC28.4, M98509, IVS27AC33.1, IVS38TG53.0) and one extragenic polymorphic marker (3'NF1). A large deletion was detected in the NF1 gene in the NF1-Noonan syndrome (NF-NS) case associated with RMS.