Enhanced response to PD-L1 silencing by modulation of TME via balancing glucose metabolism and robust co-delivery of siRNA/Resveratrol with dual-responsive polyplexes.

Since cellular metabolism reprogramming is one of the crucial hallmarks of tumor, glucose metabolic pathways are emerging as an important target for modulating immunosuppressive tumor microenvironment (TME) in favor of anti-PD-L1 therapy. Aiming at boosting immune response by modulation immunosuppressive TME via balancing the glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) of tumor cells, we developed a dual-responsive mPEG-PLA-PHis-ss-PEI polyplexes (DRP/Res/siP) for robust co-delivery of PD-L1 siRNA and resveratrol (Res). Isothermal titration calorimetry confirmed the non-electrostatic interactions between PD-L1 siRNA and PHis block of the copolymer, which contributed to the efficient and synchronized release of siRNA with Res in response to the acidic and reductive environment by destabilizing the siRNA polyplexes. The extracellular acidification rate (ECAR) and the oxygen consumption rate (OCR) as well as some key enzymes involved in glycolysis and mitochondrial OXPHOS pathways were determined to quantify the glucose metabolism balance. Effective downregulation of glycolysis and upregulation of mitochondrial OXPHOS were observed in the tumor cells treated with DRP/Res/siP, leading to remarkably reduced lactate production and glucose consumption. In vivo anti-tumor results showed that upregulation of mitochondrial OXPHOS pathways not only significantly promoted CD8+ and CD4+ T cells infiltration, IFN-γ secretion but also significantly suppressed the Treg cells and MDSCs at the same glycolysis level, resulting in superior anti-tumor effect in combination with PD-L1 silencing. Our findings indicate that balancing glucose metabolic pathways of glycolysis and mitochondrial OXPHOS provides a more reliable immune boosting strategy to PD-L1 silencing than exclusive glycolysis inhibition.

Stem cells from human exfoliated deciduous teeth correct the immune imbalance of allergic rhinitis via Treg cells in vivo and in vitro.

BACKGROUND: Several studies have demonstrated that mesenchymal stem cells can ameliorate the inflammation of allergic rhinitis (AR) and correct the Th1/Th2 immune imbalance. METHODS: This study was performed to explore the immunomodulation properties of stem cells from human exfoliated deciduous teeth (SHEDs) in the treatment of AR in vivo and in vitro. BALB/c mice were sensitized to ovalbumin (OVA) by intraperitoneal injection, and then SHEDs or bone marrow mesenchymal stem cells (BMMSCs) were injected intravenously before challenge. We evaluated nasal symptoms, inflammatory infiltration of nasal mucosa, immunoglobulin secretion, cytokine production, and mRNA expression in the spleen. In addition, peripheral blood mononuclear cells (PBMCs) from AR patients were cultured with SHEDs or BMMSCs in the presence of phytohemagglutinin (PHA). PBMCs cultured alone with or without PHA served as controls. After 3 days of culture, we examined the effect of SHEDs on T lymphocyte proliferation, cytokine secretion, and the proportion of Foxp3+ Treg cells via flow cytometry. Finally, to determine the role of soluble factors (TGF-ß1, PGE2) in the immunomodulatory mechanism, a cytokine neutralization assay was performed. RESULTS: Nasal symptoms and inflammatory infiltration were significantly reduced after SHED administration. The OVA-specific IgE and IgG1 levels in serum were significantly decreased, and the increased IL-4, IL-5, IL-13, and IL-17A levels in the spleen after OVA challenge were markedly downregulated, while the level of IFN-γ was upregulated by SHED administration. The mRNA expression levels also changed correspondingly. SHEDs significantly inhibited the proliferation of T lymphocytes; increased the levels of IFN-γ, IL-10, PGE2, and TGF-ß1; decreased the levels of IL-4 and IL-17A; and induced the expansion of Treg cells in the coculture system. The neutralization of TGF-ß1 partly relieved the immunosuppression of SHEDs, but blocking PGE2 did not. In addition, SHEDs were superior to BMMSCs in inhibiting the Th2 immune response in vivo and inducing the expansion of Treg cells in vitro. CONCLUSION: These results suggest that SHEDs could correct the CD4+ T cell immune imbalance via Treg cells and may be potential therapeutic agents for the treatment of allergic diseases, such as AR, in the future.

Upregulation of miR-216a exerts neuroprotective effects against ischemic injury through negatively regulating JAK2/STAT3-involved apoptosis and inflammatory pathways.

OBJECTIVE: Ischemic stroke remains a significant cause of death and disability in industrialized nations. Janus tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) of the JAK2/STAT3 pathway play important roles in the downstream signal pathway regulation of ischemic stroke-related inflammatory neuronal damage. Recently, microRNAs (miRNAs) have emerged as major regulators in cerebral ischemic injury; therefore, the authors aimed to investigate the underlying molecular mechanism between miRNAs and ischemic stroke, which may provide potential therapeutic targets for ischemic stroke. METHODS: The JAK2- and JAK3-related miRNA (miR-135, miR-216a, and miR-433) expression levels were detected by real-time quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis in both oxygen-glucose deprivation (OGD)-treated primary cultured neuronal cells and mouse brain with middle cerebral artery occlusion (MCAO)-induced ischemic stroke. The miR-135, miR-216a, and miR-433 were determined by bioinformatics analysis that may target JAK2, and miR-216a was further confirmed by 3' untranslated region (3'UTR) dual-luciferase assay. The study further detected cell apoptosis, the level of lactate dehydrogenase, and inflammatory mediators (inducible nitric oxide synthase [iNOS], matrix metalloproteinase-9 [MMP-9], tumor necrosis factor-α [TNF-α], and interleukin-1ß [IL-1ß]) after cells were transfected with miR-NC (miRNA negative control) or miR-216a mimics and subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) damage with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, annexin V-FITC/PI, Western blots, and enzyme-linked immunosorbent assay detection. Furthermore, neurological deficit detection and neurological behavior grading were performed to determine the infarction area and neurological deficits. RESULTS: JAK2 showed its highest level while miR-216a showed its lowest level at day 1 after ischemic reperfusion. However, miR-135 and miR-433 had no obvious change during the process. The luciferase assay data further confirmed that miR-216a can directly target the 3'UTR of JAK2, and overexpression of miR-216a repressed JAK2 protein levels in OGD/R-treated neuronal cells as well as in the MCAO model ischemic region. In addition, overexpression of miR-216a mitigated cell apoptosis both in vitro and in vivo, which was consistent with the effect of knockdown of JAK2. Furthermore, the study found that miR-216a obviously inhibited the inflammatory mediators after OGD/R, including inflammatory enzymes (iNOS and MMP-9) and cytokines (TNF-α and IL-1ß). Upregulating miR-216a levels reduced ischemic infarction and improved neurological deficit. CONCLUSIONS: These findings suggest that upregulation of miR-216a, which targets JAK2, could induce neuroprotection against ischemic injury in vitro and in vivo, which provides a potential therapeutic target for ischemic stroke.

Association between UDP-glucuronosyltransferase 2B7 tagSNPs and breast cancer risk in Chinese females.

This retrospective study was performed to evaluate the association between the UGT2B7 tagSNPs (rs12233719, rs4356975, rs7435335 and rs7441774) and breast cancer in Chinese females. Blood samples were collected from 672 patients with breast cancer and 670 healthy controls for DNA extraction. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to analyze UGT2B7 polymorphisms. Dual-luciferase reporter assays were further performed to investigate the regulatory function of UGT2B7 tagSNPs. The frequency of rs7441774 G allele in the breast cancer cases was statistically significantly higher than in the controls (0.412 vs 0.358, P = .006; odds ratio [OR] = 1.27, 95% CI = 1.08-1.48). After adjusting for conventional risk factors, individuals with the GG genotype had a higher breast cancer risk than those with the AA genotype (adjusted OR = 1.63, 95% CI = 1.18-2.26; P = .008). The GCGG haplotype of UGT2B7 was also associated with breast cancer (OR = 1.22, 95% CI = 1.04-1.45; P = .027). Meanwhile, the rs7441774 G allele could significantly decrease the transcriptional activity of the UGT2B7 gene. This study indicates that UGT2B7 polymorphisms may play a crucial role in the occurrence and development of breast cancer in the Han Chinese population.

Pharmacokinetics and pharmacodynamics of a polyethylene glycol (PEG)-conjugated GLP-receptor agonist once weekly in Chinese patients with type 2 diabetes.

This multi-center, randomized, double-blind, multiple dose-escalation study was conducted to assess the pharmacokinetics and pharmacodynamics of a newly developed polyethylene glycol (PEG)-conjugated glucagon-like peptide-1 (GLP-1) receptor agonist, PEX168 once weekly in Chinese patients with type 2 diabetes (T2DM). Fifty patients aged 20-65 years, either treatment-naive or having been treated with single oral antidiabetic agents were eligible. Antidiabetic agents were stopped for 14 days before the study was initiated. Patients were allocated randomly into groups with subcutaneous PEX168 or placebo once-weekly for 8 weeks followed by 6 weeks observation. From baseline to 8 weeks, HbA1c were decreased by up to 0.0, 0.2, 0.6, 0.9, and -0.4% in the 50, 100, 200, 300 µg PEX168 groups, and placebo group respectively. The mean elimination half-life of PEX168 was 131.8-139.8 hours. The mean tmax was 67.3 hours. Steady-state plasma PEX168 concentrations were attained after 4 weeks. PEX168 once-weekly were tolerable by the patients: adverse effects reported ranged from 'mild' to 'moderate'. The most frequent drug-related adverse effects were nausea, vomiting, and diarrhea of mild to moderate severity. Administration of the PEG-conjugated GLP-1 receptor agonist PEX168 resulted in dose-proportional pharmacokinetic and antidiabetic pharmacodynamic activity.

Pharmacoeconomics evaluation of morphine, MS contin and oxycodone in the treatment of cancer pain.

OBJECTIVE: To analyze cost-effectiveness of morphine, MS contin and oxycodone in the treatment of cancer pain, providing guidance for rational drug use in the clinic. METHODS: Confirmed by histology, a total of 171 patients with various cancers who required analgesic treatment were selected and divided into 3 groups, 57 cases for each group, given morphine, MS contin and oxycodone, respectively. If there appeared a poor short-term effect or aggravated sudden pain during the treatment, a short-acting morphine injection was given and adverse reactions were processed by symptomatic treatment. The pain relief rate and adverse reactions of groups were observed and pharmacoeconomics evaluation was undertaken. RESULTS: The pain relief rates with morphine, MS contin and oxycodone were 89.5%(51/57), 91.2%(52/57) and 93.0%(53/57), respectively, with no difference samong groups (χ2=4.4489, P=0.6162). The occurrence rates of adverse reactions were 59.7%(34/57), 54.4%(31/57) and 43.9%(25/57), again with no significant variation (P>0.05). The ratios of cost-effectiveness (C/E) for the 3 groups were 14.6±7.21, 15.0±7.44 and 16.1±8.10. When the price of 3 kinds of analgesics was reduced by 10%, the ratios of cost-effectiveness were 12.2±6.53, (13.4±6.08 and 14.5±6.74 but there was no differences when compared with before the price adjustment (t=1.86, P=0.0651; t=1.30, P=0.1948; t=1.17, P=0.2453). CONCLUSION: Morphine, MS contin and oxycodone give similar pain relief and adverse reaction rates but of all, morphine is the preferred drug for the treatment of cancer pain from the perspective of pharmacoeconomics.

[Progress in the study of targeted drug delivery systems for cancer stem cells].

The discovery, sorting and identification methods as well as targeted drug delivery systems for cancer stem cells (CSCs) have been reviewed by consulting the recent research papers. CSCs have been believed to be responsible for the occurrence and development of chemo-resistance, leading to the failure of chemotherapy. Much progress has been made in the approaches for CSCs targeting drug delivery systems. The understanding and targeted drug delivery systems for CSCs are promising to provide an alternative for cancer therapy.

[Analysis of gene mutation in a Chinese family with Norrie disease].

OBJECTIVE: To detect the pathogenic mutation in a Chinese family with Norrie disease. METHODS: Clinical diagnosis was based on familial history, clinical sign and B ultrasonic examination. Peripheral blood samples were obtained from all available members in a Chinese family with Norrie disease. Genomic DNA was extracted from lymphocytes by the standard SDS-proteinase K-phenol/chloroform method. Two coding exons and all intron-exon boundaries of the NDP gene were PCR amplified using three pairs of primers and subjected to automatic DNA sequence. The causative mutation was confirmed by restriction enzyme analysis and genotyping analysis in all members. RESULTS: Sequence analysis of NDP gene revealed a missense mutation c.220C > T (p.Arg74Cys) in the proband and his mother. Further mutation identification by restriction enzyme analysis and genotyping analysis showed that the proband was homozygote of this mutation. His mother and other four unaffected members (III3, IV4, III5 and II2) were carriers of this mutation. The mutant amino acid located in the C-terminal cystine knot-like domain, which was critical motif for the structure and function of NDP. CONCLUSION: A NDP missense mutation was identified in a Chinese family with Norrie disease.

[The characterisitics of temperature/pH sensitive block copolymer micelles in vitro].

The dialysis method was employed to prepare blank and doxorubicin (DOX) loaded micelles formed by temperature- and pH- sensitive polyhistidine-co-polyDL-lactide-co-glycolide-co-polyethyleneglycol-co-polyDL-lactide-co-glycolide-co-polyhistidine (PHis-b-PLGA-b-PEG-b-PLGA-b-PHis). The critical micelle concentrations (CMC) of the copolymers were measured with Pyrene Fluorescent Probe Technique. The temperature- and pH- sensitive properties of the blank micelles solution were investigated by optical transmittance measurement. The morphology and diameter of DOX micelles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The entrapment rate and drug-loading rate were determined with dialysis method. The in vitro release study was further performed to examine the temperature- and pH-responsive drug release behavior from DOX-loaded micelles. The results indicated that the CMC, entrapment efficiency and drug-loaded amount of the micelles were 7.5 x 10(-3) g x L(-1), 85.2 +/- 3.1% and 10.4 +/- 4.5%, respectively. The DOX micelle was globular-shaped with a mean diameter of 91.1 +/- 15.8 nm. The transmittance of micelle solution consistently increased with the increasing temperature or decreasing pH. In comparison to the drug release profile at physiological conditions (37 degrees C, pH 7.4), the DOX-loaded micelles showed faster drug release rate at higher temperature (41 degrees C), lower pH (pH 7.0, pH 6.5, pH 5.0) or higher temperature and lower pH (41 degrees C, pH 5.0). This indicated that the micelles showed a temperature and pH-triggered drug release pattern. Base on the above results, it can be concluded that PHis-b-PLGA-b-PEG-b-PLGA-b-PHis block copolymer micelles which respond to temperature and pH stimuli are promising smart carriers for anti-tumor drugs with the advantages of temperature- and pH- triggered drug release.

Preparation and characterization of ß-elemene-loaded microemulsion.

Intravenously injectable emulsion of ß-elemene was studied in detail. Both blank and ß-elemene-loaded microemulsions were prepared using a simple water titration method. The pseudoternary phase diagram was constructed for the optimization of microemulsion. The loading capacity test, dilutability test, and especially the influence of antioxidants were conducted for further optimization of ß-elemene-loaded microemulsion. Transmission electron microscope showed intact and spherical microemulsion droplets. Conductivity and viscosity measurements were used to study the phase behaviors of ß-elemene-loaded microemulsions, providing convincing explanation. In vitro release study showed that ß-elemene was steadily released until 12 h, which most fitted the first order.

Preparation and characterization of nanostructured lipid carriers loaded traditional Chinese medicine, zedoary turmeric oil.

BACKGROUND: The objective of this work was to study the preparation and characteristics of zedoary turmeric oil (ZTO), a traditional Chinese oily medicine, loaded with nanostructured lipid carriers (NLCs). METHOD: Aqueous dispersions of NLC were successfully prepared by melt-emulsification technique using Crodamol SS as the solid lipid, Miglyol 812N as the liquid oil, and soybean phosphatidylcholine (SbPC) as the emulsifier. Properties of NLC such as the particle size and its distribution, the transmission electron microscope (TEM), drug entrapment efficiency (EE), and drug release behavior were investigated, respectively. The Germacrone blood concentration after intravenous administration of ZTO-NLC was determined and compared with that of ZTO-injection. RESULT: As a result, the drug EEs were improved by adding the liquid lipid into the solid lipid of nanoparticles (SLNs). In vitro drug release experiments indicated that the prepared NLC could enhance the drug release rate over the SLN, and the drug release rate could be adjusted by the liquid lipid content in lipid nanospheres. X-ray and differential scanning calorimetry (DSC) measurements revealed that imperfect crystallization occurred in the inner core of the NLC particles. CONCLUSION: The results suggest that the presented NLC system might be a promising intravenous dosage form of water-insoluble oily drugs.

[Preparation of adriamycin-loaded temperature/pH sensitive self-assembly block copolymer micelles].

The dialysis method was employed to load adriamycin into the micelles formed by temperature and pH sensitive polyhistidine-co-DL-lactide-co-glycolide-polyethylene glycol poly DL-lactide-co-glycolide-co-histidine (OLH-b-PLGA-b-PEG-b-PLGA-b-OLH). The critical micelle concentration (CMC) of the copolymer was measured with pyrene fluorescent probe method under different temperatures. The entrapment rate and drug-loading rate were determined with dialysis method. The diameter, morphology and surface potential of the copolymer micelles were investigated by corresponding instruments, respectively. The release behavior of adriamycin from copolymer micelles and the pH sensitivity were studied. The CMC of the copolymers ranged from 0.022 4 to 0.001 7 microg x mL(-1). The entrapment rate and drug-loading rate were 92.8% and 15.7%, respectively. The micelles have a mean diameter of (61.7 +/- 13.4) nm, and zeta potential was -9.88 mV. The in vitro adriamycin release rate increased with the pH dropping from 7.4 to 5.0. The results indicated that the CMC of the copolymers decreased as the raising of temperature, drug release behavior from the micelles possessed clearly pH sensitivity, and the copolymers may have a potential in targeted delivery system for anticancer drugs.

[Identification of a novel TP53 germline mutation in one child with adrenocortical carcinoma].

OBJECTIVE: To detect the germline TP53 gene mutation in a child with pediatric adrenocortical carcinoma (ADCC) in order to provide genetic diagnosis and counseling. METHODS: Genomic DNA was extracted from peripheral blood from a girl with ADCC and her parents. All TP53 exons and their flanking intronic sequences were PCR-amplified and subjected to automatic DNA sequencing. RESULTS: Direct sequencing of PCR products revealed a heterozygous G insertion between nucleotide 522 and 523 (c.522-523insG) in TP53 exon 5. This novel mutation is predicted to result in a frame shift at codon 175, producing a new reading frame ending in a stop at position 6 (p.R175AfsX6). The same heterozygous mutation was also found in her father, but not in her mother. CONCLUSION: A novel germline mutation in the TP53 gene has been identified in one case with pediatric ADCC.

[Primary risk factors in Chinese patients with first acute myocardial infarction].

OBJECTIVE: To analyze the primary risk factors of patients with first ST elevation acute myocardial infarction (FSTEMI) in Beijing and Shenyang area between 2004--2005. The Attributable risk percentage (ARP) and population attributable risk percentage (PARP) of every risk factor were determined. METHOD: A total of 426 consecutive FSTEMI patients and 426 gender and age matched healthy controls were included in this 1:1 matched case-control study. RESULT: Multivariate logistic regression analysis showed that following 8 primary risk factors were associated with FSTEMI: heavy smoking (OR = 3.170), diabetes (OR = 2.835), positive family history (OR = 2.243), lack of soybeans intake (OR = 2.243), higher psychological stress (OR = 2.138), lack of fish intake (OR = 1.740), lower education level (OR = 1.572) and recent adverse life events (< 6 months before FSTEMI, OR = 1.515). The ARP are 71.53%, 58.33%, 54.05%, 40.81%, 56.85%, 41.53%, 48.62%, 54.00%; the PARP are 38.79%, 10.40%, 4.69%, 33.72%, 36.03%, 24.96%, 29.56%, 14.83%, respectively. CONCLUSION: In this patient cohort, the harmful risk factors responsible for the development of FSTEMI in Beijing and Shenyang areas during 2004--2005 are heavy smoking, higher psychological stress, lack of soybeans intake, lower education level, lack of fish intake, recent adverse life events, diabetes and positive family history.

[Preparation of docetaxel-loaded pH-sensitive block copolymer micelles].

Basing on the synthesis of pH-sensitive amphiphilic block copolymer poly (2-ethyl-2-oxazoline)-poly (D, L-lactide)(PEOz-PDLLA), this paper presents the preparation of docetaxel-loaded pH-sensitive block copolymer micelles using film dispersion method. The critical micelle concentration (CMC) was measured by pyrene fluorescent probe technique. The entrapment efficiency and drug-loaded amount were determined by HPLC. The morphology, diameter and surface potential of the micelles were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential analyzer, respectively. The in vitro release behavior of DTX from polymeric micelles was investigated using dialysis method. The results indicated that the CMC, drug-loaded amount and entrapment efficiency of the micelles was 1.0 x 10(-3) g x L(-1), 15.0% and 91.1%, respectively. The micelles had a narrow size distribution, with a mean diameter of 28.7 nm. The micelle was globular-shaped and its zeta potential was (1.19 +/- 0.12) mV. In pH 7.4 PBS, docetaxel was released in a sustained manner from the micelles; while in PBS at pH 5.0, drug was released more rapidly, which suggested the pH-sensitive drug release behavior of the PEOz-PDLLA micelles. According to all the studies above, it can be concluded that the PEOz-PDLLA block copolymer micelles may be applied as promising drug delivery system for hydrophobic anti-tumor drugs.

[Preparation and in vitro tumor cells selectivity of sterically stabilized immunoliposomal peptides in bee venom].

Recently the use of peptides in bee venom (PBV) for cancer therapy has attracted considerable attention. In this study, the sterically stabilized liposomal PBV (PBV-SL) was prepared using soybean phosphatidylcholine, cholesterol, and cholesterol-PEG-COOH. The humanized antihepatoma disulfide-stabilized Fv (hdscFv25) was coupled to sterically stabilized liposomes using the N-hydroxysuccinimide ester method. The hdscFv25-immunoliposomes (SIL[hdscFv25]) were immunoreactive as determined by ELISA assay. SIL[hdscFv25] showed higher tumor cells selectivity. PBV-SIL[hdscFv25] can kill SMMC-7721 cells in vitro with higher efficiency than non-targeted liposomes. Whereas cytotoxicties were compared for Hela cells, no significant differences was observed between PBV-SIL[hdscFv25] and PBV-SL. Sterically stabilized immunoliposomal peptides in bee venom could be one drug targeting delivery system.

[HOXD13 polyalanine tract expansion in synpolydactyly: mutation detection and prenatal diagnosis in a large Chinese family].

OBJECTIVE: Synpolydactyly (SPD, MIM 186000), also known as syndactyly type II, is a dominantly inherited limb malformation with incomplete penetrance and variable expressivity. Polyalanine tract expansion in HOXD13 has been shown to be the disease-causing mutation in SPD. The present study was designed to identify mutation in HOXD13 and to provide prenatal diagnosis, in a large Chinese SPD family consisting of 54 individuals. METHODS: The proband and 4 other affected individuals in the family were evaluated physically and radiologically to ascertain the SPD phenotype. Genomic DNA was extracted from peripheral blood samples obtained from 18 family members (9 affected and 9 unaffected), and from amniotic fluid and chorionic villus samples obtained from the proband during her two consecutive pregnancies. With the use of a pair of specific primers, a fragment of 161bp was amplified by polymerase chain reaction (PCR) to cover the imperfect GCN triplet repeat sequence in exon 1 of HOXD13 encoding the 15-residue polyalanine tract. The PCR products were detected by agarose gel electrophoresis, and sequenced after cloning into pMD18T vector. To confirm prenatal diagnosis, haplotype analysis was also performed by allele-typing three microsatellite markers, including the intronic CA repeats in HOXD13. RESULTS: Digital and radiographic findings indicated a typical SPD phenotype in the family. These included 3/4 finger syndactyly and 4/5 toe syndactyly with an extra digit in the syndactylous web. Unilateral finger syndactyly in the proband, unilateral toe syndactyly in 2 individuals, bilateral brachydactyly of the fifth toes in 1 individual, and clinodactyly of the fifth fingers in 4 individuals were also observed, indicating variable expressivity. Gel electrophoresis of the PCR products showed an additional longer fragment in all 9 affected individuals but not in the unaffected ones. Sequence analysis of the longer fragment revealed a 9-alanine expansion. The expansion was detectable in DNA from the amniotic fluid and chorionic villus samples. Furthermore, haplotype analysis ruled out potential contamination of the maternal DNA. These suggested that the two fetuses carried the same polyalanine expansion. CONCLUSION: HOXD13 polyalanine expansion was detected in a large Chinese family with SPD and prenatal diagnosis of two affected fetuses was achieved. This is the first report on prenatal diagnosis of SPD by detecting the HOXD13 polyalanine expansion in the Han population of the Chinese mainland.