Abstract 1643: p53 family and oncogenic signaling in cancer metastasis

The tumor suppressor protein p53 is mutated in over 50% of human cancers. Multiple lines of evidence have shown that mutant p53 not only loses its ability to inhibit tumorigenesis, but also gains pro-metastatic functions. However, the molecular mechanisms underlying these effects are still not totally understood. In this study, we demonstrate that the p53 hotspot point mutant, p53(R273H), potently induces cell spreading, migration, and invasion. At the molecular level, p53(R273H) regulates the DLX2-NRP2 pathway in promoting cancer cell migration in vitro and metastasis in vivo. Interestingly, p53(R273H) strongly inhibits tumor cell growth in vitro and in xenograft nude mice model. In addition, we show that p53-related p63 inhibits Erk2 signaling in regulating cell migration/invasion.

Citation Format: Zhi-Xiong Xiao, Tao Lv, Yang Wan, Johann Bergholz, Yujun Zhang. p53 family and oncogenic signaling in cancer metastasis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1643.

Nanoscale Electron Bunching in Laser-Triggered Ionization Injection in Plasma Accelerators

Ionization injection is attractive as a controllable injection scheme for generating high quality electron beams using plasma-based wakefield acceleration. Because of the phase-dependent tunneling ionization rate and the trapping dynamics within a nonlinear wake, the discrete injection of electrons within the wake is nonlinearly mapped to a discrete final phase space structure of the beam at the location where the electrons are trapped. This phenomenon is theoretically analyzed and examined by three-dimensional particle-in-cell simulations which show that three-dimensional effects limit the wave number of the modulation to between >2k_{0} and about 5k_{0}, where k_{0} is the wave number of the injection laser. Such a nanoscale bunched beam can be diagnosed by and used to generate coherent transition radiation and may find use in generating high-power ultraviolet radiation upon passage through a resonant undulator.

Capturing relativistic wakefield structures in plasmas using ultrashort high-energy electrons as a probe

A new method capable of capturing coherent electric field structures propagating at nearly the speed of light in plasma with a time resolution as small as a few femtoseconds is proposed. This method uses a few femtoseconds long relativistic electron bunch to probe the wake produced in a plasma by an intense laser pulse or an ultra-short relativistic charged particle beam. As the probe bunch traverses the wake, its momentum is modulated by the electric field of the wake, leading to a density variation of the probe after free-space propagation. This variation of probe density produces a snapshot of the wake that can directly give many useful information of the wake structure and its evolution. Furthermore, this snapshot allows detailed mapping of the longitudinal and transverse components of the wakefield. We develop a theoretical model for field reconstruction and verify it using 3-dimensional particle-in-cell (PIC) simulations. This model can accurately reconstruct the wakefield structure in the linear regime, and it can also qualitatively map the major features of nonlinear wakes. The capturing of the injection in a nonlinear wake is demonstrated through 3D PIC simulations as an example of the application of this new method.

Meta-analysis of the IL-10 promoter polymorphisms and pediatric asthma susceptibility

The results of previous epidemiological studies exploring the relationship between interleukin-10 (IL-10) promoter polymorphisms and susceptibility to pediatric asthma are not consistent. Therefore, we have performed a systematic review and meta-analysis to provide a more convincing conclusion. Odds ratios (OR) with their 95% confidence intervals (CIs) were used to evaluate the strength of association between the IL-10 promoter polymorphisms and susceptibility to pediatric asthma. Publication bias was examined by Begg's funnel plots and the Egger test. A detailed literature search based on stringent parameters yielded sixteen relevant studies, comprising 2494 cases and 2160 controls. The overall population showed no significant association between the IL-10 -1082G/A polymorphism and pediatric asthma risk in any of the genetic models (dominant model: OR = 1.583, 95%CI = 0.614-4.076, P = 0.342; allelic model: OR = 1.214, 95%CI = 0.748-1.971, P = 0.433; additive model: OR = 2.240, 95%CI = 0.950-5.277, P = 0.065; recessive model: OR = 1.435, 95%CI = 0.659-3.128, P = 0.363). Subgroup analyses revealed a significant association between different ethnicity and atopic status subgroups. However, there was no evidence of a significant association between the other two polymorphisms (-819C/ T and -592C/A) and pediatric asthma in our study. No significant publication bias was observed in this meta-analysis. The results of this study indicate that the IL-10 -1082G/A polymorphism might be a risk factor for asthma in children. However, because of the small sample size included in the subgroup analyses, the results should be interpreted with caution.

Cardiac Specific Overexpression of hHole Attenuates Isoproterenol-Induced Hypertrophic Remodeling through Inhibition of Extracellular Signal-Regulated Kinases (ERKs) Signalling

The human Hole gene (hHole) encodes a six-transmembrane protein with 319- amino acids. Our previous study showed that hHole was strongly expressed in adult heart and may act as a suppressor of extracellular signal-regulated kinases (ERKs), overactivation of which contributed to pathological cardiac hypertrophy. In this study, it was observed that Hole expression was up-regulated in murine hypertrophic hearts. In a cardiac specific transgenic mouse model, it was observed that overexpression of hHole specifically in heart attenuated cardiac hypertrophy and fibrosis induced by isoproterenol (ISO), with blunted transcriptions of ERK1/2, total ERK1/2 proteins and phosphorylated ERK1/2 (p-ERK1/2) levels. Furthermore, overexpression of hHole in mice by hydrodynamic tail-vein injection with hHole plamids also inhibited cardiac hypertrophy induced by ISO. Our work identified hHole as a novel repressor of cardiac hypertrophy, and provided new insights into the possible target for the prevention or treatment of cardiac diseases.

Endosome Escape Strategies for Improving the Efficacy of Oligonucleotide Delivery Systems

Gene therapy requires safe and effective vectors to deliver genes to their target site of action. Non-viral gene delivery systems have attracted growing attention due to their low toxicity, low immunogenicity and ease of production compared to viral vectors. Most non-viral gene delivery systems enter cells via endocytic pathways, and their escape from endosomes is therefore crucial for successful transfection. Several reagents have been developed to promote endosomal escape, including peptides, polymers and lipids. Among these, endosome-disrupting peptides have been used in many studies, and have proven to be one of the most promising approaches to overcome endosomal entrapment and lysosomal degradation. This review provides an up-to-date summary of strategies for enhancing endosomal escape, with a focus on the modification of endosome-disrupting peptides to further increase the efficient delivery of oligonucleotides.

[Clinical and genetic features of dyskeratosis congenital with bone marrow failure in eight patients]

目的

加深对先天性角化不良（dyskeratosis congenital，DC）伴骨髓衰竭的认识。

方法

收集2010年9月30日至2015年9月30日8例伴骨髓衰竭DC患儿的临床资料，利用二代测序技术对DKC1、TERC、TERT、NOP10、NHP2、TINF2等16种端粒相关基因进行全外显子及剪接位点测序分析。

结果

8例DC患儿中男6例、女2例，中位发病月龄为42(15~60）个月。初诊血常规：中位WBC 3.99（1.26~5.44）×10⁹/L，中位中性粒细胞计数1.11(0.38~2.15）×10⁹/L，中位RBC 2.45(0.37~3.56）×10¹²/L，中位HGB 82.5(15~127) g/L，中位PLT 27（2~112）×10⁹/L。8例患儿中6例骨髓增生减低或重度减低。3例患儿检出DKC1基因突变：c.961C>A 1例，c.1058C>T 2例；4例患儿检出TINF2基因突变：c.849delC、c.844C>T、c.811C>T、c.862T>A合并c.871delA各1例；1例患儿检出TINF2基因突变（c.848C>A）合并TERT基因突变（c.1138C>T）。其中DKC c.961C>A、TINF2 c.849delC、TINF2 c.871delA突变为首次报道。7例患儿口服雄激素治疗，其中5例血常规指标改善。1例患儿死于重症感染，其余7例患儿维持治疗。

结论

DC伴骨髓衰竭以TINF2突变和DKC1突变为主。雄激素治疗对部分病例有效。

Physics of Phase Space Matching for Staging Plasma and Traditional Accelerator Components Using Longitudinally Tailored Plasma Profiles

Phase space matching between two plasma-based accelerator (PBA) stages and between a PBA and a traditional accelerator component is a critical issue for emittance preservation. The drastic differences of the transverse focusing strengths as the beam propagates between stages and components may lead to a catastrophic emittance growth even when there is a small energy spread. We propose using the linear focusing forces from nonlinear wakes in longitudinally tailored plasma density profiles to control phase space matching between sections with negligible emittance growth. Several profiles are considered and theoretical analysis and particle-in-cell simulations show how these structures may work in four different scenarios. Good agreement between theory and simulation is obtained, and it is found that the adiabatic approximation misses important physics even for long profiles.

Transcriptome analysis reveals a ribosome constituents disorder involved in the RPL5 downregulated zebrafish model of Diamond-Blackfan anemia

BACKGROUND

Diamond-Blackfan anemia (DBA) was the first ribosomopathy associated with mutations in ribosome protein (RP) genes. The clinical phenotypes of DBA include failure of erythropoiesis, congenital anomalies and cancer predisposition. Mutations in RPL5 are reported in approximately 9 ~ 21 % of DBA patients, which represents the most common pathological condition related to a large-subunit ribosomal protein. However, it remains unclear how RPL5 downregulation results in severe phenotypes of this disease.

RESULTS

In this study, we generated a zebrafish model of DBA with RPL5 morphants and implemented high-throughput RNA-seq and ncRNA-seq to identify key genes, lncRNAs, and miRNAs during zebrafish development and hematopoiesis. We demonstrated that RPL5 is required for both primitive and definitive hematopoiesis processes. By comparing with other DBA zebrafish models and processing functional coupling network, we identified some common regulated genes, lncRNAs and miRNAs, that might play important roles in development and hematopoiesis.

CONCLUSIONS

Ribosome biogenesis and translation process were affected more in RPL5 MO than in other RP MOs. Both P53 dependent (for example, cell cycle pathway) and independent pathways (such as Aminoacyl-tRNA biosynthesis pathway) play important roles in DBA pathology. Our results therefore provide a comprehensive basis for the study of molecular pathogenesis of RPL5-mediated DBA and other ribosomopathies.

Long-term association between dairy consumption and risk of childhood obesity: a systematic review and meta-analysis of prospective cohort studies

BACKGROUND/OBJECTIVES

Data from small-scale, short-term, clinical trials suggest a beneficial effect of dairy consumption on the risk of childhood obesity; however, the long-term association is unclear. Therefore, we aim to examine the longitudinal association between dairy consumption and the risk of overweight/obesity in children and adolescents by conducting a systematic review and meta-analysis of prospective cohort studies.

SUBJECTS/METHODS

Eligible studies were identified by searching PubMed and EMBASE through March 2015. Additional studies were retrieved via Google Scholar or a hand review of the reference lists from relevant articles. Pooled associations of interest were estimated by using a random-effects model. The heterogeneity for each pooled analysis was evaluated by I(2) statistic as well as by Cochran's Q test. Publication bias was assessed by using both Egger's and Begg's tests.

RESULTS

Ten studies comprising 46,011 children and adolescents with an average 3-year follow-up were included. As compared with those who were in the lowest group of dairy consumption, children in the highest intake group were 38% less likely to have childhood overweight/obesity (pooled odds ratio (OR)=0.62; 95% confidence interval (CI): 0.49, 0.80). With each 1 serving/day increment in dairy consumption, the percentage of body fat was reduced by 0.65% (β=0.65; 95% CI: -1.35, 0.06; P=0.07), and the risk of overweight/obesity was 13% lower (OR=0.87; 95% CI: 0.74, 0.98).

CONCLUSIONS

Accumulated evidence from prospective cohort studies suggests that dairy consumption is inversely and longitudinally associated with the risk of childhood overweight/obesity. Further studies are warranted to examine the types of dairy products in relation to the risk of childhood overweight/obesity.

Spontaneous renal hemorrhage caused by invasive mole: a case report

CASE

The authors report a case with spontaneous renal hemorrhage caused by invasive mole. The diagnosis was gestational trophoblastic disease (GTD), with metastasis to brain, kidneys, and lungs at Stage IV. The patient was given etoposide-methotrexate-actinomycin D plus cyclophosphamide-vincristine (EMACO) treatment regimen for 11 times including three times with consolidation chemotherapies. Laparoscopically-assisted vaginal hysterectomy (LAVH) + laparoscopic-assisted left renal excision + evacuation of the left perirenal hematoma were performed during the eighth chemotherapy.

CONCLUSION

Post-operational pathological examination revealed trophoblasts within the lesions present in uterine fundus and the residue images of a few trophoblasts present in the left renal mass.

Bmi1 promotes erythroid development through regulating ribosome biogenesis

While Polycomb group protein Bmi1 is important for stem cell maintenance, its role in lineage commitment is largely unknown. We have identified Bmi1 as a novel regulator of erythroid development. Bmi1 is highly expressed in mouse erythroid progenitor cells and its deficiency impairs erythroid differentiation. BMI1 is also important for human erythroid development. Furthermore, we discovered that loss of Bmi1 in erythroid progenitor cells results in decreased transcription of multiple ribosomal protein genes and impaired ribosome biogenesis. Bmi1 deficiency stabilizes p53 protein, leading to upregulation of p21 expression and subsequent G0/G1 cell cycle arrest. Genetic inhibition of p53 activity rescues the erythroid defects seen in the Bmi1 null mice, demonstrating that a p53-dependent mechanism underlies the pathophysiology of the anemia. Mechanistically, Bmi1 is associated with multiple ribosomal protein genes and may positively regulate their expression in erythroid progenitor cells. Thus, Bmi1 promotes erythroid development, at least in part through regulating ribosome biogenesis. Ribosomopathies are human disorders of ribosome dysfunction, including Diamond-Blackfan anemia (DBA) and 5q- syndrome, in which genetic abnormalities cause impaired ribosome biogenesis, resulting in specific clinical phenotypes. We observed that BMI1 expression in human hematopoietic stem and progenitor cells from patients with DBA is correlated with the expression of some ribosomal protein genes, suggesting that BMI1 deficiency may play a pathological role in DBA and other ribosomopathies.

Synthetic innate defense regulator peptide combination using CpG ODN as a novel adjuvant induces long‑lasting and balanced immune responses

Vaccines are critical tools for the prevention and treatment of several diseases. Adjuvants have been traditionally used to enhance immunity to vaccines and experimental antigens. In the present study, the adjuvant combination of CpG oligodeoxynucleotides (CpG ODN) and the innate defense regulator (IDR) peptide, IDR‑HH2, was evaluated for its ability to enhance and modulate the immune response when formulated with alum and the recombinant hepatitis B surface antigen (HBsAg). The CpG‑HH2 complex enhanced the secretions of tumor necrosis factor‑α, monocyte chemotactic protein 1 and interferon‑γ by human peripheral blood mononuclear cells and promoted murine bone marrow dentritic cell maturation. In addition, the present study demonstrated that IDR‑HH2 was chemotactic for human neutrophils, THP‑1 cells and RAW264.7 cells at concentrations between 2.5 and 40 µg/ml. The present study also observed that significantly higher anti‑HBs antibody titers, which were sustained at high levels for as long as 35 weeks following the boost immunization, were induced by the combination adjuvant, even when co‑administered with a commercial hepatitis B vaccine at a low antigen dose (0.1 µg HBsAg). Notably, the level of IgG2a was almost equal to the level of IgG1, indicating that a balanced T helper (Th)1/Th2 immune response was elicited by the novel vaccine, which was consistent with the ELISpot results. These data suggest that the CpG‑HH2 complex may be a potential effective adjuvant, which facilitates a reduction in the dose of antigen and induces long‑lasting, balanced immune responses.

Genetically modified human placenta‑derived mesenchymal stem cells with FGF‑2 and PDGF‑BB enhance neovascularization in a model of hindlimb ischemia

Ischemic diseases represent a challenging worldwide health burden. The current study investigated the therapeutic potential of genetically modified human placenta‑derived mesenchymal stem cells (hPDMSCs) with basic fibroblast growth factor (FGF2) and platelet‑derived growth factor‑BB (PDGF‑BB) genes in hindlimb ischemia. Mesenchymal stem cells obtained from human term placenta were transfected ex vivo with adenoviral bicistronic vectors carrying the FGF2 and PDGF‑BB genes (Ad‑F‑P). Unilateral hindlimb ischemia was surgically induced by excision of the right femoral artery in New Zealand White rabbits. Ad‑F‑P genetically modified hPDMSCs, Ad‑null (control vector)‑modified hPDMSCs, unmodified hPDMSCs or media were intramuscularly implanted into the ischemic limbs 7 days subsequent to the induction of ischemia. Four weeks after cell therapy, angiographic analysis revealed significantly increased collateral vessel formation in the Ad‑F‑P‑hPDMSC group compared with the control group. Histological examination revealed markedly increased capillary and arteriole density in the Ad‑F‑P‑hPDMSC group. The xenografted hPDMSCs survived in the ischemic tissue for at least 4 weeks subsequent to cell therapy. The current study demonstrated that the combination of hPDMSC therapy with FGF2 and PDGF‑BB gene therapy effectively induced collateral vessel formation and angiogenesis, suggesting a novel strategy for therapeutic angiogenesis.

Prediction of outcomes by early treatment responses in childhood T-cell acute lymphoblastic leukemia: a retrospective study in China

BACKGROUND

Early treatment responses are important prognostic factors in childhood T-cell acute lymphoblastic leukemia (T-ALL) patients. The predictive values of early treatment responses in Chinese childhood T-ALL patients were still unknown.

METHODS

From January 2003 to December 2012, 74 consecutive patients aged ≤ 15 years with newly diagnosed T-ALL were treated with BCH-2003 protocol or CCLG-2008 protocol in the Department of Pediatric, Institute of Hematology and Blood Diseases Hospital in China. Predictive values of early treatment responses, including prednisone response, bone marrow morphology at day 15 and day 33 during induction chemotherapy, and minimal residual disease (MRD) monitored by flow cytometry after induction therapy (time point 1, TP1) and before consolidation therapy (time point 2, TP2), were analyzed.

RESULTS

The 5-year event free survival (EFS) and overall survival (OS) rates for these patients were 62.5% (SE, 6.4) and 62.7% (SE, 6.6), respectively. Prednisone poor responder was strongly associated with increased chance of induction failure (14.8%) and decreased survival rate (5 year EFS rate, 51.1 % (SE, 10.5)). Patients with ≥ 25% blast cells in bone marrow at day 15 were more likely to have an inferior outcome. 93.2% of the T-ALL patients achieved complete remission at day 33 while patients with resistant disease all died of disease progression. MRD ≥ 10(-2) at TP1 or MRD ≥ 10(-3) at TP2 was significantly related to dismal prognosis. Risk groups classified by MRD at two time points could stratify patients into different groups: 29.0% of the patients were MRD standard risk (MRD < 10(-4) at both time points) with 3-year EFS rate of 100%, 29.0% were MRD high risk (MRD ≥ 10(-2) at TP1 or MRD ≥ 10(-2) at TP2) with 3-year EFS rate of 55.6% (SE, 16.6) , and the rest of patients were defined as MRD intermediate risk with 3-year EFS rate of 85.7% (SE, 13.2).

CONCLUSION

Our study demonstrated that MRD was the most powerful predictor of treatment outcome in childhood T-ALL patients and conventional morphological assessments of treatment response still played important roles in predicting treatment outcome and tailoring treatment intensity especially in countries with inadequate skills or financial resources for MRD monitoring.

[Prognostic Value of Prednisone Response in CCLG-ALL 2008]

OBJECTIVE

To ovaluate the prognostic value of prednisone response in treatment regimes of children with acute lymphoblastic leukemia.

METHODS

A total of 598 newly diagnosed ALL patients were enrolled and received prednisone pre-treatment. Based on the peripheral lymphoblast count on day 8, these patients were divided into 2 groups: prednisone good response (PGR) and prednisone poor response (PPR). PPR patients were classified into high risk group immediately and then received intensed chemotherapy. The all enrolled patients were followed up and the clinical features and treatment outcomes of the two groups were analyzed.

RESULTS

Compared with PGR group, PPR group had different characteristics. They were older in age and had higher initial white blood cell count (P<0.05). T-cell ALL (T-ALL) and Philadelphia chromosome positive ALL (Ph+ ALL) were frequent in PPR group (P<0.05). Event-free survival (EFS) rate of PPR group was significantly lower than that of PGR group (P<0.05). 2 year event-free survival(EFS) rate of PGR group was (88.3±1.5)%, while the 2-year EFS rate of PPR group was (58.4±5.3)%. 5 year EFS rates of PGR and PPR were (80.8±2.1)% and (53.4±6.0)%, respectively. The EFS rate of PPR group was falling rapidly within 2 years. PPR group had higher relapse rate, and most relapses occurred within 18 months (P<0.05). PPR group had more high incidence of minimal residual disease (MRD) both on day 33 and on week 12 (P<0.05). No significant difference of EFS and relapse time was found between PPR and high risk PGR patients (P>0.05). In multi-variate regression analysis, the PPR, the presence of BCR-ABL1 and MLL were significantly unfavorable factors (P<0.05).

CONCLUSION

Prednisone response has been confirmed to be still great prognostic value and PPR children patients have poor outcomes generally. It is likely that the response to prednisone does not make much sense to high risk ALL patients.

Inhibitory effect of liposomal quercetin on acute hepatitis and hepatic fibrosis induced by concanavalin A

Immune response plays an important role in the development of hepatic fibrosis. In the present study, we investigated the effects of quercetin on hepatitis and hepatic fibrosis induced by immunological mechanism. In the acute hepatitis model, quercetin (2.5 mg/kg) was injected iv into mice 30 min after concanavalin A (Con A) challenge. Mice were sacrificed 4 or 24 h after Con A injection, and aminotransferase tests and histopathological sections were performed. Treatment with quercetin significantly decreased the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Consistent with this observation, treatment with quercetin markedly attenuated the pathologic changes in the liver. A hepatic fibrosis model was also generated in mice by Con A challenge once a week for 6 consecutive weeks. Mice in the experimental group were treated with daily iv injections of quercetin (0.5 mg/kg). Histopathological analyses revealed that treatment with quercetin markedly decreased collagen deposition, pseudolobuli development, and hepatic stellate cells activation. We also examined the effects of quercetin on the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and transforming growth factor beta (TGF-β) pathways by immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction (RT-PCR). NF-κB and TGF-β production was decreased after treatment with quercetin, indicating that the antifibrotic effect of quercetin is associated with its ability to modulate NF-κB and TGF-β production. These results suggest that quercetin may be an effective therapeutic strategy in the treatment of patients with liver damage and fibrosis.

Effect of daily short-duration weight-bearing on disuse-induced deterioration of musculoskeletal system

OBJECTIVES

To investigate deterioration of musculoskeletal system due to prolonged disuse and the potential of daily short-duration weight-bearing as countermeasures.

METHODS

Twenty-four adult male Sprague-Dawley rats were divided into Control Group (CG, no intervention), Tail-suspension Group (TG, tail-suspension without treatment), and Weight-Bearing Group (WBG, tail-suspension with 20 min/day, 5 days/week body weight loading). After four weeks of treatment, femur and tibia, soleus and extensor digitorum longus were evaluated for bone and muscle quality respectively. Tensile properties of bone-tendon insertion (BTI) were evaluated using patella-patellar tendon complex.

RESULTS

Disuse induced deterioration on bone, muscle, and BTI after four weeks. Compared with CG, TG and WBG showed significant decrease in bone mineral density (BMD) of trabecular bone in distal femur (4.3-15.2%), muscle mass (31.3-52.3%), muscle cross-sectional area (29.1-35%), and failure strength of BTI (23.9-29.4%). Tensile test showed that the failure mode was avulsion of bone at the BTI. No significant difference was detected between TG and WBG for all assessments on bone, muscle, and BTI.

CONCLUSIONS

Disuse caused deterioration of bone, muscle, and BTI while daily short-duration of weight-bearing did not prevent this deterioration. Mechanical stimulation with higher intensity and longer duration may be necessary to prevent musculoskeletal deterioration resulted from prolonged disuse.

Mutation analysis of Chinese sporadic congenital sideroblastic anemia by targeted capture sequencing

Background

Congenital sideroblastic anemias (CSAs) comprise a group of heterogenous genetic diseases that are caused by the mutation of various genes involved in heme biosynthesis, iron-sulfur cluster biogenesis, or mitochondrial solute transport or metabolism. However, approximately 40 % of patients with CSA have not been found to have pathogenic gene mutations. In this study, we systematically analyzed the mutation profile in 10 Chinese patients with sporadic CSA.

Findings

We performed targeted deep sequencing analysis in ten patients with CSA using a panel of 417 genes that included known CSA-related genes. Mitochondrial genomes were analyzed using next-generation sequencing with a mitochondria enrichment kit and the HiSeq2000 sequencing platform. The results were confirmed by Sanger sequencing. The ALAS2 mutation was detected in one patient. SLC25A38 mutations were detected in three patients, including three novel mutations. Mitochondrial DNA deletions were detected in two patients. No disease-causing mutations were detected in four patients.

Conclusion

To our knowledge, the pyridoxine-effective mutation C471Y of ALAS2, the compound heterozygous mutation W87X, I143Pfs146X, and the homozygous mutation R134C of SLC25A38 were found for the first time. Our findings add to the number of reported cases of this rare disease and to the CSA pathogenic mutation database. Our findings expand the phenotypic profile of mitochondrial DNA deletion mutations. This work also demonstrates the application of a congenital blood disease assay and targeted capture sequencing for the genetic screening analysis and diagnosis of heterogenous genetic CSA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-015-0154-0) contains supplementary material, which is available to authorized users.