原因不明习惯性流产患者封闭抗体活性与肿瘤坏死因子-α的关系

目的观察原因不明习惯性流产(RSA)患者的封闭抗体效应与辅助性T细胞(Th)1型免疫之间的关系。方法以20例连续发生过3次以上早期自然流产的患者作为观察对象。采用比重离心法从外周血中提取淋巴细胞,以1×106/ml浓度加入含有1%小牛血清的RPMI中。每毫升淋巴细胞悬浮液中加入植物血凝素(PHA)2μg培养72 h。采用酶联免疫吸附试验(ELISA法)检测培养液中肿瘤坏死因子(TNF)-α的水平。采用混合淋巴细胞培养方法检测研究对象的封闭抗体效应(MLR-BE),>22%为阳性,≤22%为阴性。分析TNF-α水平与MLR-BE的关系。结果20例患者TNF-α的平均浓度为(561.0±522.9)pg/ml,平均MLR-BE为(-6.5±37.6)%(阴性14例、阳性6例)。MLR-BE阴性患者的TNF-α水平为(676.1±585.0)pg/ml,显著高于MLR-BE阳性患者的(292.5±159.5)pg/ml(P<0.05)。TNF-α水平与MLR-BE不相关(R2=0.015,P>0.05)。结论MLR-BE可能影响母体Th1/Th2的平衡,从而导致习惯性流产的发生。     

Borderline resectable pancreatic cancer: rationale for multidisciplinary treatment

Background

Borderline resectable pancreatic cancer (BRPC) appears to be most frequently related to a positive surgical margin and has a poor prognosis after resection. However, few reports are available on differences in tumor characteristics and prognoses among resectable pancreatic cancer (PC), BRPC, and unresectable PC.

Methods

Records of 133 patients resected for pancreatic ductal adenocarcinoma and 185 patients treated as locally advanced PC (LAPC) were reviewed.

Results

Twenty-four patients who initially underwent resection (BRPC-s) and 10 patients who were initially treated as LAPC (BRPC-n) met the criteria for BRPC. Prognosis of BRPC was significantly better than that of unresectable PC, but was significantly worse than that of resectable PC. BRPC-s showed more frequent nerve plexus invasion (P < 0.01), portal vein invasion (P < 0.01), and loco-regional recurrence (P = 0.03) than resectable PC. The positive surgical margin rate was not significantly higher in BRPC-s (29%) than in resectable PC (19%) (P = 0.41).

Conclusions

BRPC had a poorer prognosis with more local failure than resectable PC although prognosis of BRPC was significantly better than that of unresectable PC. Considering the tumor and treatment characteristics, multidisciplinary treatment including resection is required for BRPC.     

Lack of non-hematological cross intolerance of dasatinib to imatinib in imatinib-intolerant patients with Philadelphia chromosome positive chronic myeloid leukemia or acute lymphatic leukemia: a retrospective safety analysis

The aim of this retrospective study was to evaluate the toxicity profiles of dasatinib in patients with Philadelphia chromosome positive chronic myeloid leukemia (CML) or acute lymphatic leukemia (ALL) who were intolerant to imatinib, and who had been enrolled in our previous clinical trials to evaluate efficacy of dasatinib in patients resistant or tolerant to imatinib therapy. Twenty-four patients with CML and four with ALL were enrolled in the clinical studies to evaluate the efficacy according to the eligibility criteria related to intolerance to imatinib therapy. The toxicities reported during imatinib therapy were non-hematological toxicities in 23 patients and hematological toxicities in six patients. Patients were administered dasatinib 50-70 mg BID or 100 mg QD. Cross intolerance was observed in four patients who showed hematological toxicity after dasatinib treatment. However, it was possible to successfully continue therapy with only temporary interruption. No cross intolerance in non-hematological toxicity was found with the exception of one patient who showed cross intolerance, which did not result in treatment interruption. Dasatinib can be safely administered to imatinib-intolerant CML or Ph-positive ALL patients.     

Cancer specific promoter CpG Islands hypermethylation of homeodomain only protein X gene and its potential tumor suppressive role in pancreatic carcinogenesis

ABSTRACT: BACKGROUND: We have recently identified homeodomain only protein X (HOPX) as a tumor suppressor gene candidate, characterized by tumor-specific promoter DNA hypermethylation in human cancers, and it can remarkably inhibit tumors' aggressive phenotypes. In this current study, we for the first time examined methylation level of HOPX and tested the functional relevance in pancreatic cancer (PC). METHODS: Clinical features of HOPX promoter hypermethylation was investigated in 89 PC tissues, and immunohistochemistry was added. We also examined its functional relevance in phenotype assays such as soft agar, proliferation, invasion, and cell cycle analysis. RESULTS: PC tissues had HOPX gene hypermethylation as compared to the corresponding normal pancreas tissues, and its uniqueness was robust to discriminate tumor from normal tissues (AUC = 0.85, P < 0.0001). Unexpectedly, HOPX was increased in expression in tumor tissues, and immunohistochemistry revealed its predominant expression in the Langerhans islet cells, where HOPX is reduced in expression for PC cells with promoter hypermethylation. HOPX transfectants exhibited G1 arrest with subG1 accumulation, and inhibit tumor forming and invasive ability. CONCLUSION: Defective expression of HOPX which is consistent with promoter DNA hypermethylation may explain aggressive phenotype of pancreatic cancer, and intense expression of HOPX in the Langerhans cells may in turn uniquely contribute to pancreatic carcinogenesis.     

Epigenetic Silencing of HOPX Promotes Cancer Progression in Colorectal Cancer

Homeodomain-only protein X (HOPX)-β promoter methylation was recently shown to be frequent in human cancers and was suggested as tumor suppressor gene in esophageal and gastric cancer. The aim of this study was to investigate the mechanistic roles of HOPX-β promoter methylation and its clinical relevance in colorectal cancer (CRC). HOPX-β promoter methylation was assessed in human CRC cell lines and 294 CRC tissues. HOPX mRNA and protein levels were measured in relation to HOPX-β promoter methylation. The effects of forced HOPX expression on tumorigenesis were studied using in vitro and in vivo assays. The association between HOPX-β promoter methylation and clinical relevance of CRC patients was determined. HOPX-β promoter methylation is cancer-specific and frequently found in CRC cell lines and tissues, resulting in the down-regulation of HOPX mRNA and protein levels. In CRC cell lines, forced expression of HOPX suppressed proliferation, invasion, and anchorage-independent growth. DNA microarray analyses suggested critical downstream genes that are associated with cancer cell proliferation, invasion or angiogenesis. In a mouse xenograft model, HOPX inhibited tumorigenesis and angiogenesis. Finally, HOPX-β promoter methylation was associated with worse prognosis of stage III CRC patients (hazard ratio= 1.40, P = .035) and also with poor differentiation (P = .014). In conclusion, HOPX-β promoter methylation is a frequent and cancer-specific event in CRC progression. This epigenetic alteration may have clinical ramifications in the diagnosis and treatment of CRC patients.     

Uptake of 3-[125I]iodo-α-methyl-l-tyrosine into colon cancer DLD-1 cells: characterization and inhibitory effect of natural amino acids and amino acid-like drugs

IntroductionWe examined 3-[¹²³I]iodo-α-methyl-l-tyrosine ([¹²³I]IMT) uptake and inhibition by amino acids and amino acid-like drugs in the human DLD-1 colon cancer cell line, to discuss correlation between the inhibition effect and structure.MethodsExpression of relevant neutral amino acid transporters was examined by real-time PCR with DLD-1 cells. The time course of [¹²⁵I]IMT uptake, contributions of transport systems, concentration dependence and inhibition effects by amino acids and amino acid-like drugs (1 mM) on [¹²⁵I]IMT uptake were examined.ResultsExpression of system L (4F2hc, LAT1 and LAT2), system A (ATA1, ATA2) and system ASC (ASCT1) was strongly detected; system L (LAT3, LAT4) and MCT8 were weakly detected; and B⁰AT was not detected. [¹²⁵I]IMT uptake in DLD-1 cells involved Na⁺-independent system L primarily and Na⁺-dependent system(s). Uptake of [¹²⁵I]IMT in Na⁺-free buffer followed Michaelis–Menten kinetics, with a K_m of 78 μM and V_max of 333 pmol/10⁶ cells per minute. Neutral d- and l-amino acids with branched or aromatic large side chains inhibited [¹²⁵I]IMT uptake. Tyrosine analogues, tryptophan analogues, l-phenylalanine and p-halogeno-l-phenylalanines, and gamma amino acids [including 3,4-dihydroxy-l-phenylalanine (l-DOPA), dl-threo-β-(3,4-dihydroxyphenyl)serine (DOPS), 4-[bis(2-chloroethyl)amino]-l-phenylalanine and 1-(aminomethyl)-cyclohexaneacetic acid] strongly inhibited [¹²⁵I]IMT uptake, but l-tyrosine methyl ester and R(+)/S(?)-baclofen weakly inhibited uptake. The substrates of system ASC and A did not inhibit [¹²⁵I]IMT uptake except l-serine and d/l-cysteine.Conclusions[¹²⁵I]IMT uptake in DLD-1 cells involves mostly LAT1 and its substrates' (including amino acid-like drugs derived from tyrosine, tryptophan and phenylalanine) affinity to transport via LAT1. Whether transport of gamma amino acid analogues is involved in LAT1 depends on the structure of the group corresponding to the amino acid residue. Beta-hydroxylation may confer reduction of transport affinity of tyrosine analogues via LAT1.     

Radioiodinated 4-iodo-L-meta-tyrosine, a system L selective artificial amino acid: molecular design and transport characterization in Chinese hamster ovary cells (CHO-K1 cells)

IntroductionHigh expression of the system L amino acid transporter has been observed in clinically important tissues including tumors and the blood-brain barrier. We examined amino acid transport system L selectivity of ¹⁴C(U)-l-tyrosine (¹⁴C-Tyr), ¹²⁵I-4-iodo-l-meta-tyrosine (4-¹²⁵I-mTyr), ¹²⁵I-6-iodo-l-meta-tyrosine (6-¹²⁵I-mTyr), ¹²⁵I-3-iodo-α-methyl-l-tyrosine (¹²⁵I-IMT) and ¹²⁵I-3-iodo-l-tyrosine (3-¹²⁵I-Tyr) using Chinese hamster ovary cells (CHO-K1).MethodsCells in the exponential growth phase were incubated with 18.5 kBq of labeled amino acid in 2 mL of phosphate-buffered saline-based uptake solution and an uptake solution with/without Na⁺ at 37°C or 4°C. We examined the effects of the following compounds (1.0 mM) on transport: 2-(methylamino)isobutyric acid (a specific inhibitor of system A, in Na⁺-containing uptake solution); 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid (a specific inhibitor of system L, in Na⁺-free uptake solution); sodium azide and 2,4-dinitrophenol (NaN₃ and DNP, inhibitors of the generation of adenosine triphosphate); p-aminohippurate and tetraethylammonium (PAH and TEA, inhibitors of organic anion and cation transporters); and l- and d-isomers of natural amino acids.Results¹⁴C-Tyr exhibited affinity for systems L, A and ASC. 4-¹²⁵I-mTyr and 3-¹²⁵I-Tyr exhibited high specificity for system L, whereas 6-¹²⁵I-mTyr and ¹²⁵I-IMT exhibited affinity for both systems L and ASC. Uptake of 4-¹²⁵I-mTyr was markedly reduced by incubation at 4 °C, and was not significantly inhibited by NaN₃, DNP, PAH or TEA. The inhibition profiles of the l- and d-isomers of natural amino acids indicated that system L mediates the transport of 4-¹²⁵I-mTyr.Conclusions4-¹²⁵I-mTyr exhibited the greatest system L specificity (93.46±0.13%) of all of the tested amino acids.     

Concordance Rates of Birth Defects After Assisted Reproductive Technology Among 17 258 Japanese Twin Pregnancies: A Nationwide Survey, 2004–2009

Background

Most twins after assisted reproductive technology (ART) are dizygotic. Analysis of dizygotic twin pairs is useful in assessing familial aggregation in the development of birth defects.

Methods

Using nationwide post-ART data from the Japan Society of Obstetrics and Gynecology, recurrence risk ratios (RRRs)—defined as probandwise concordance rates of birth defects in twins divided by the prevalence of birth defects in the general population—were calculated as indicators of familial aggregation. Birth defects were then reclassified according to the ICD-10 categories corresponding to codes Q00–Q99. From 2004 to 2009, there were 17 258 twin pregnancies.

Results

At least 1 birth defect was noted in 236 twin pairs: 11 concordant and 225 discordant pairs. Regarding major organ systems, high probandwise concordance rates were observed for congenital malformations of eye, ear, face, and neck (11.8%), cleft lip and cleft palate (10.5%), congenital malformations of the nervous system (9.8%), and other congenital malformations of the digestive system (9.5%). High RRRs were observed for congenital malformations of eye, ear, face, and neck (RRR = 233), specifically other congenital malformations of the ear (RRR = 449); congenital malformations of the great arteries (RRR = 235), specifically those of the patent ductus arteriosus (RRR = 530); and for cleft lip and cleft palate (RRR = 208), specifically cleft palate with cleft lip (RRR = 609). The probandwise concordance rate of any birth defect (8.9%) was nearly identical to the approximated recurrence risk of sib-pairs (8.8%), which assumed multifactorial inheritance.

Conclusions

The present findings suggest that familial aggregation is a factor in some birth defects.Key words: birth defects, assisted reproductive technology (ART), twin pairs, concordance rate, nationwide epidemiologic study     

Transcellular transport of 4-iodo-L-meta-tyrosine via system L across monolayers of kidney epithelial cell line LLC-PK1

The substance 4-[(125)I]iodo-L-meta-tyrosin (4-[(125)I]mTyr) is a radioiodinated amino acid that exhibits high in vivo stability and rapid renal elimination in vivo. We investigated transport of 4-[(125)I]mTyr in LLC-PK(1) (porcine kidney epithelial cell line) monolayers grown on collagen-coated, micro-porous membrane filters. We found that 4-[(125)I]mTyr transport in LLC-PK(1) cells was carrier-mediated and sodium-independent, and that 4-[(125)I]mTyr transport was similar to that of L-Tyr and 3-iodo-alpha-methyl-L-tyrosine. The results of the inhibition experiments suggest that 4-[(125)I]mTyr transport is predominantly mediated by a L-type amino acid transporter 1-like porcine homologue (a component of system L) in both basolateral and apical membrane.