Polyneuropathy organomegaly endocrinopathy M-protein and skin changes syndrome with ascites as an early-stage manifestation: A case report.

BACKGROUND: Polyneuropathy organomegaly endocrinopathy M-protein and skin changes (POEMS) syndrome is a rare paraneoplastic syndrome caused by a potential plasma cell tumor. The clinical manifestations of POEMS syndrome are diverse. Due to the insidious onset and lack of specific early-stage manifestations, POEMS syndrome is easily misdiagnosed or never diagnosed, leading to delayed treatment. Neurological symptoms are usually the first clinical manifestation, while ascites is a rare symptom in patients with POEMS syndrome. CASE SUMMARY: A female patient presented with unexplained ascites as an initial symptom, which is a rare early-stage manifestation of the condition. After 1 year, the patient gradually developed progressive renal impairment, anemia, polyserosal effusion, edema, swollen lymph nodes on the neck, armpits, and groin, and decreased muscle strength of the lower extremities. The patient was eventually diagnosed with POEMS syndrome after multidisciplinary team discussion. Treatment comprised bortezomib + dexamethasone, continuous renal replacement therapy, chest and abdominal closed drainage, transfusions of erythrocytes and platelets, and other symptomatic and supportive treatments. The patient's condition initially improved after treatment. However, then her symptoms worsened, and she succumbed to the illness and died. CONCLUSION: Ascites is a potential early manifestation of POEMS syndrome, and this diagnosis should be considered for patients with unexplained ascites. Furthermore, multidisciplinary team discussion is helpful in diagnosing POEMS syndrome.

Portal hypertension exacerbates intrahepatic portosystemic venous shunt and further induces refractory hepatic encephalopathy: A case report.

BACKGROUND: Intrahepatic portosystemic venous shunt (IPSVS) is a rare hepatic disease with different clinical manifestations. Most IPSVS patients with mild shunts are asymptomatic, while the patients with severe shunts present complications such as hepatic encephalopathy. For patients with portal hypertension accompanied by intrahepatic shunt, portal hypertension may lead to hemodynamic changes that may result in exacerbated portal shunt and increased shunt flow. CASE SUMMARY: A 57-year-old man, with the medical history of chronic hepatitis B and liver cirrhosis, was admitted to our hospital with abnormal behavior for 10 mo. He had received the esophageal varices ligation and entecavir therapy 1 year ago. Comparing with former examination results, the degree of esophageal varices was significantly reduced, while the right branch of the portal vein was significantly expanded and tortuous. Meanwhile, abdominal ultrasound presented the right posterior branch of portal vein connected with the retrohepatic inferior vena cava. The imaging findings indicated the diagnosis of IPSVS and hepatic encephalopathy. Instead of radiologic interventions or surgical therapies, this patient had only accepted symptomatic treatment. No recurrence of hepatic encephalopathy was observed during 1-year follow-up. CONCLUSION: Hemodynamic changes may exacerbate intrahepatic portosystemic shunt. The intervention or surgery should be carefully applied to patients with severe portal hypertension due to the risk of hemorrhage.

An Integrated Microarray Analysis Reveals Significant Diagnostic and Prognostic Biomarkers in Pancreatic Cancer.

BACKGROUND Pancreatic cancer (PAC) is a lethal cancer and it is essential to develop accurate diagnostic and prognostic biomarkers for PAC. MATERIAL AND METHODS An integrated microarray analysis of PAC was conducted to identify differentially expressed genes (DEGs) between PAC and non-tumor controls. Expression of DEGs were further confirmed by The Cancer Genome Atlas and the Genotype-Tissue Expression. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis, and protein-protein integration network construction were performed to further research the biological functions of DEGs. Receiver-operating characteristic analysis and survival analysis were used to evaluate the diagnostic and prognostic value of DEGs for PAC. RESULTS Seventeen microarray datasets were downloaded from Gene Expression Omnibus to conduct the integrated microarray analysis. A total of 1136 DEGs (596 upregulated and 540 downregulated DEGs) in PAC tissues compared with non-tumor controls were identified. Pancreatic secretion (Kegg: 04972), insulin signaling pathway (Kegg: 04910), and several cancer-related pathways including pathways in cancer (Kegg: 05200), MAPK signaling pathway (Kegg: 04010), and pancreatic cancer (Kegg: 05212) were enriched for DEGs in PAC. Seven DEGs (AHNAK2, CDH3, IFI27, ITGA2, LAMB3, SLC6A14, and TMPRSS4) were found to have both great diagnostic and prognostic value for PAC. High expression of these 7 DEGs were significantly associated with poor prognosis of patients with PAC. CONCLUSIONS These 7 DEGs might be potential diagnostic and prognostic biomarkers for PAC and help uncovering the mechanism of PAC.

The oncoprotein HBXIP competitively binds KEAP1 to activate NRF2 and enhance breast cancer cell growth and metastasis.

The nuclear factor E2-related factor 2 (NRF2)-Kelch-like ECH-associated protein 1 (KEAP1) signaling cascades is a key transcriptional pathway governing cellular oxidative stress and tumor development. Mammalian hepatitis B X-interacting protein (HBXIP) has critical roles in modulating cancer malignance and tumor progression. However, whether HBXIP interacts with KEAP1 and NRF2 is unclear. Here, we found that HBXIP can effectually compete with NRF2 for binding with KEAP1 protein via its highly conserved GLNLG motif. The HBXIP-mediated reduction in NRF2-KEAP1 complexes promotes NRF2 accumulation and nuclear entry, which facilities the activation of antioxidant response element (ARE)-dependent signaling cascades, thereby reducing the accumulation of endogenous cellular reactive oxygen species (ROS). We also found a strong positive correlation between HBXIP expression and NRF2 expression in breast cancer cells, tissue microarrays and clinical breast cancer tissues. Furthermore, this positive correlation was further confirmed via analysis of 1905 clinical cases of breast carcinoma provided by the cancer genomics database cBioPortal. Strikingly, disrupting the HBXIP-KEAP1 axis via mutating the GLNLG motif of HBXIP leads to potent inhibition of the malignancy of breast carcinoma both in vivo and in vitro. Our findings broaden our understanding of HBXIP as a modulation factor of cellular oxidative stress and address a novel regulatory mechanism governing redox homeostasis and the progression of breast carcinoma.

Author Correction: Diversity and bioactive potential of culturable fungal endophytes of Dysosma versipellis; a rare medicinal plant endemic to China.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Diversity and bioactive potential of culturable fungal endophytes of Dysosma versipellis; a rare medicinal plant endemic to China.

The plant Dysosma versipellis is known for its antimicrobial and anticancer properties but is a rare and vulnerable perennial herb that is endemic to China. In this study, 224 isolates were isolated from various tissues of D. versipellis, and were classified into 53 different morphotypes according to culture characteristics and were identified by sequence analyses of the internal transcribed spacer (ITS) region of the rRNA gene. Although nine strains were not assignable at the phylum level, 44 belonged to at least 29 genera of 15 orders of Ascomycota (93%), Basidiomycota (6%), and Zygomycota (1%). Subsequent assays revealed antimicrobial activities of 19% of endophytic extracts against at least one pathogenic bacterium or fungus. Antimicrobial activity was also determined using the agar diffusion method and was most prominent in extracts from four isolates. Moreover, high performance liquid chromatography (HPLC) and ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry analyses (UPLC-QTOF MS) showed the presence of podophyllotoxin in two Fusarium strains, with the highest yield of 277 µg/g in Fusarium sp. (WB5121). Taken together, the present data suggest that various endophytic fungi of D. versipellis could be exploited as sources of novel natural antimicrobial or anticancer agents.

The LPI/GPR55 axis enhances human breast cancer cell migration via HBXIP and p-MLC signaling.

The G protein-coupled receptor 55 (GPR55) is expressed in multiple tissues, and has been implicated in cancer pathogenesis, but little is known about its role in the migratory behavior of cancer cells, particularly breast cancer cells. In this study we first showed that GPR55 expression levels in 38 metastatic lymph nodes of breast cancer patients were profoundly elevated, and were positively associated in human breast cancer cells with their migratory ability. Moreover, the plasma levels of GPR55 endogenous agonist L-a-lysophosphatidylinositol (LPI) were significantly increased in breast cancer patients compared with healthy individuals. In human breast cancer LM-MCF-7 and MDA-MB-231 cells, treatment with LPI (2.5 µmol/L) significantly increased filopodia formation and resulted in cell migration, which could be blocked either by the GPR55 antagonist CID16020046 or by siRNA-mediated GPR55 knockdown. Furthermore, dual-luciferase report gene assays showed that GPR55 upregulated HBXIP at the promoter; GPR55 expression levels were positively correlated with HBXIP expression levels in breast cancer tissues and 8 breast cancer cell lines. We also showed that the LPI/GPR55 axis promoted the migration of breast cancer cells via two mutually exclusive pathways - the HBXIP/p-ERK1/2/Capn4 and MLCK/MLC signaling pathways. In xenograft nude mouse model, loss of GPR55 mainly affected breast cancer cell metastasis and the formation of metastatic foci. Thus, GPR55 is involved in the migratory behavior of human breast cancer cells and could serve as a pharmacological target for preventing metastasis.

Inhibition of autophagy enhances effects of PF-04691502 on apoptosis and DNA damage of lung cancer cells.

Autophagy modulation has been considered as a potential therapeutic strategy for lung diseases. The PI3K-Akt-mTOR pathway may be one of the main targets for regulation of autophagy. We previously reported that a PI3K/mTOR dual inhibitor PF-04691502 suppressed hepatoma cells growth in vitro. However, it is still unclear whether PF-04691502 induces autophagy and its roles in DNA damage and cell death in human lung cancer cells. In this study, we investigate the effects of PF-04691502 on the autophagy and its correlation with cell apoptosis and DNA damage in non-small-cell lung cancer (NSCLC) cell lines. PF-04691502 efficiently inhibited the phosphorylation of Akt and showed dose-dependent cytotoxicity in A549 and H1299 cells. PF-04691502 also triggered apoptosis and the cleavage of caspase-3 and PARP. Phosphorylated histone H2AX (γ-H2AX), a hallmark of DNA damage response, was dramatically induced by PF-04691502 treatment. By exposure to PF-04691502, A549 cells acquired a senescent-like phenotype with an increase in the level of ß-galactosidase. Furthermore, PF-04691502 enhanced the expression of LC3-II in a concentration-dependent manner. More interestingly, effects of PF-04691502 on toxicity and DNA damage were remarkably increased by co-treatment with an autophagy inhibitor, chloroquine (CQ), in human lung cancer cells. These data suggest that a strategy of blocking autophagy to enhance the activity of PI3K/mTOR inhibitors warrants further attention in treatment of NSCLC cells.

Norditerpenoid alkaloids from Delphinium anthriscifolium.

Two new norditerpenoid alkaloids with lycoctonine skeleton, anthriscifolcones A (1) and B (2), were isolated from the whole plant of Delphinium anthriscifolium var. Majus by extensive column chromatography. Their structures were established by IR, MS, (1)H NMR, (13)C NMR, and 2D NMR methods (including HSQC, (1)H-(1)H COSY, HMBC, and NOESY experiments).

Repeated pancreatitis-induced splenic vein thrombosis leads to intractable gastric variceal bleeding: A case report and review.

Gastric varices (GV) are one of the most common complications for patients with portal hypertension. Currently, histoacryl injection is recommended as the initial treatment for bleeding of GV, and this injection has been confirmed to be highly effective for most patients in many studies. However, this treatment might be ineffective for some types of GV, such as splenic vein thrombosis-related localized portal hypertension (also called left-sided, sinistral, or regional portal hypertension). Herein, we report a case of repeated pancreatitis-induced complete splenic vein thrombosis that led to intractable gastric variceal bleeding, which was treated by splenectomy. We present detailed radiological and pathological data and blood rheology analysis (the splenic artery - after a short gastric vein or stomach vein - gastric coronary vein - portal vein). The pathophysiology can be explained by the abnormal direction of blood flow in this patient. To our knowledge, this is the first reported case for which detailed pathology and blood rheology data are available.

[Study on chemical constituents of Citrullus vulgaris Schrad vine (II)].

OBJECTIVE: To study the chemical constituents of ethyl acetate fraction of Citrullus vulgaris Schrad vine. METHODS: Compounds were isolated and purified by polyamide column chromatography, silica gel column chromatography, thin layer chromatography and sephadex gel column chromatography. Their structures were elucidated on the basis of physicochemical properties and spectral data. RESULTS: Ten compounds were isolated from Citrullus vulgaris Schrad vine and elucidated as: pentadecanoic acid (1), monopentadecanoin (2), 2, 3-dihydroxypropyl nonadecoate (3), lignoceric acid-2, 3-dihydroxy-propanenyl ester (4), lancerebroside 5 (5), salicylic acid (6), 4-hydroxybenzoic acid (7), hydroquinone (8), succinic acid (9) and vanillic acid (10). CONCLUSION: Compounds 1 - 10 are obtained from Citrullus vulgaris Schrad vine for the first time.

[Microscopic observation on mycorrhiza of rare herb Dysosma versipellis].

Endophytic fungi played an important role in the growth of its host plant. To investigate the mycorrhizal characteristics and the distribution of fungi in the root, an endangered wild plant-Dysosma versipellis was collected and observed by electron microscope. The results showed that the host was closely associated with endophytic fungi. The fungi were mainly distributed in the epidermis and cortex. The aseptate and septate fungi with swollen hyphae were observed in some cell of the cortex. The result provides a reference for the study of mycorrhizal structure of Dysosma genus and the interaction between the fungi and its host.

[The polymorphisms of XRCC1 gene and susceptibility to pulmonary cancer].

OBJECTIVE: To explore the relationship between the polymorphisms of DNA repair gene XRCC1 and susceptibility to pulmonary cancer. METHODS: A case-control study of 209 lung cancer patients and 256 control subjects was conducted to investigate the role of XRCC1 gene in lung cancer. Genotyping was performed using PCR based restriction fragment length polymorphism (PCR-RFLP) technique. RESULTS: The frequency (19.1%) of XRCC1-194 Trp/Trp in case group was significantly higher than that (10.9%) in control group (P < 0.05), OR for lung cancer was 2.215 (95% CI: 1.276-3.845). The frequency (6.7%) of XRCC1-280 His/His in case group was significantly higher than that (4.3%) in control group (P < 0.05), OR for lung cancer was 2.46 (95% CI: 1.141-5.304). There was no significant difference for XRCC1-399 Gln/Gln genotype between the two groups. Interaction analysis of gene polymorphisms and environment factors indicated that there was interactions between XRCC1-194 Trp/Trp and XRCC1-280 His/His genotypes and smoking. The risks of lung cancer in smokers with XRCC1-194 Arg/Trp+Trp/Trp and XRCC1-280 His/His+Arg/His were 4.889 (95% CI: 2.828-8.452) and 6.281(95% CI: 3.572-11.046), respectively. CONCLUSION: These findings supported the hypothesis that the interaction of polymorphisms of XRCC1-194 Trp/Trp, XRCC1-280 His/His with smoking resulted in the increased risk of lung cancer, and the polymorphisms of XRCC and smoking could play an role in development of lung cancer.

[Preventive effects of modified chitosan medical anti-adhesion membrane on postoperative intra-abdominal adhesion].

OBJECTIVE: To explore the preventive effects of modified chitosan medical anti-adhesion membrane on postoperative intra-abdominal adhesion. METHODS: A total of 86 patients with obstructive colorectal carcinoma undergoing emergent colostomy and second-stage anastomosis were randomly divided into 2 groups (n = 43 each). In the research group modified chitosan medical anti-adhesion membrane were put both at the area of operation and under the incision before abdomen closing, but not so in the control group. The recovery procedures were recorded including gut movement, degree and duration of abdominal pain and cases of adhesive ileus. During the reopening of abdominal cavities 3 to 6 months later, intestinal anastomosis was performed. And adhesive severity was graded blindly and the level of hydroxyproline measured within injured posterior peritoneum and adhesive tissue. RESULTS: As compared with the control, postoperative abdominal pain was weaker; the recovery of gut motor function and eating better ((3.3 ± 1.0) vs (4.2 ± 1.1) days, P < 0.05), the incidence of adhesive ileus lower (1(2.3%) vs 4(9.3%), P < 0.05), adhesion significantly lighter and the hydroxyproline level lower ((0.832 ± 0.071) vs (1.375 ± 0.108) µg/mg protein, P < 0.05) in the research group. CONCLUSION: Modified chitosan medical anti-adhesion membrane has preventive effects on postoperative intra-abdominal adhesion so as to decrease the incidence of adhesive ileus.

Myosin light chain kinase is responsible for high proliferative ability of breast cancer cells via anti-apoptosis involving p38 pathway.

AIM: To investigate whether myosin light chain kinase (MLCK) contributed to the high proliferative ability of breast cancer cells. METHODS: Soft agar colony formation on the MCF-7 and LM-MCF-7 cell lines was determined. The cell cycles of MCF-7 and LM-MCF-7 were detected using flow cytometry analysis. Western blot analysis was performed to detect the expression levels of p-ERK1/2, total-ERK1/2, p-p38, total p38, p-JNK, total-JNK, survivin, Bcl-2, p-MLC, caspase-9, cleaved caspase-9, and MLCK. After treatment with adriamycin (ADR), ML-7 and SB203580, apoptosis was examined using flow cytometry analysis and Annexin V-FITC fluorescence microscopy. RESULTS: The breast cancer LM-MCF-7 cell line with high metastasis potential (a metastitic sub-clone of MCF-7) had higher anti-apoptosis ability relative to MCF-7 cells in response to adriamycin treatment (apoptosis rate: 6.76% vs 28.58%, P<0.05). Moreover, the expression level of MLCK was upregulated and the level of phosphorylated p38 (p-p38) was decreased in LM-MCF-7 cells. Flow cytometry analysis showed that ML-7, selective inhibitor of MLCK, could induce apoptosis of the LM-MCF-7 cells, in which the level of p-p38 was increased. Meanwhile, the expression levels of Bcl-2 and survivin were downregulated, while the caspase-9 was upregulated suggesting that the cells were undergone apoptosis. Flow cytometry analysis showed that SB203580, an inhibitor of p38, abolished ML-7-induced apoptosis, which resulted in the upregulation of Bcl-2 and survivin, and downregulation of caspase-9, suggesting that Bcl-2, survivin and caspase-9 are downstream effectors of p38. CONCLUSION: MLCK is responsible for high proliferative ability of breast cancer cells through anti-apoptosis, in which p38 pathway was involved.

Common variants in human CRC genes as low-risk alleles.

The genetic susceptibility to colorectal cancer (CRC) has been estimated to be around 35% and yet high-penetrance germline mutations found so far explain less than 5% of all cases. Much of the remaining variations could be due to the co-inheritance of multiple low penetrant variants. The identification of all the susceptibility alleles could have public health relevance in the near future. To test the hypothesis that what are considered polymorphisms in human CRC genes could constitute low-risk alleles, we selected eight common SNPs for a pilot association study in 1785 cases and 1722 controls. One SNP, rs3219489:G>C (MUTYH Q324H) seemed to confer an increased risk of rectal cancer in homozygous status (OR=1.52; CI=1.06-2.17). When the analysis was restricted to our 'super-controls', healthy individuals with no family history for cancer, also rs1799977:A>G (MLH1 I219V) was associated with an increased risk in both colon and rectum patients with an odds ratio of 1.28 (CI=1.02-1.60) and 1.34 (CI=1.05-1.72), respectively (under the dominant model); while 2 SNPs, rs1800932:A>G (MSH6 P92P) and rs459552:T>A (APC D1822V) seemed to confer a protective effect. The latter, in particular showed an odds ratio of 0.76 (CI=0.60-0.97) among colon patients and 0.73 (CI=0.56-0.95) among rectal patients. In conclusion, our study suggests that common variants in human CRC genes could constitute low-risk alleles.

Downregulation of Dickkopf-1 is responsible for high proliferation of breast cancer cells via losing control of Wnt/beta-catenin signaling.

AIM: To investigate the role of DKK-1/Wnt/beta-catenin signaling in high proliferation of LM-MCF-7 breast cancer cells, a sub-clone of MCF-7 cell line. METHODS: Two cell lines (MCF-7 and LM-MCF-7) with different proliferation abilities were used. LM-MCF-7 cells were transiently transfected with the pcDNA3-DKK-1 plasmid encoding the DKK-1 gene (or MCF-7 cells were transfected siRNA targeting DKK-1 mRNA). Flow cytometry analysis and 5-bromo-2'-deoxyuridine (BrdU) incorporation assay were applied to detect the cell proliferation. The expression levels of beta-catenin, phosphorylated beta-catenin, c-Myc, cyclin D1 and Survivin were examined by Western blot analysis. The regulation of Survivin was investigated by Luciferase reporter gene assay. RESULTS: Western blot and RT-PCR analysis showed that the expression level of DKK-1 was downregulated in LM-MCF-7 relative to MCF-7 cells. Flow cytometry and BrdU incorporation assay showed DKK-1 could suppress growth of breast cancer cells. Overexpression of DKK-1 was able to accelerate phosphorylation-dependent degradation of beta-catenin and downregulate the expression of beta-catenin, c-Myc, cyclin D1 and Survivin. Luciferase reporter gene assay demonstrated that Survivin could be regulated by beta-catenin/TCF4 pathway. CONCLUSION: We conclude that the downregulation of DKK-1 is responsible for the high proliferation ability of LM-MCF-7 breast cancer cells via losing control of Wnt/beta-catenin signaling pathway, in which c-Myc, cyclinD1 and Survivin serve as essential downstream effectors. Our finding provides a new insight into the mechanism of breast cancer cell proliferation.

[Personal protective and healthcare seeking behaviors urban residents before and during an influenza pandemic in Beijing].

OBJECTIVE: To provide evidence-based recommendations to the government on strategies for reducing the impact of the imminent influenza pandemic, we conducted a survey on the personal protective and healthcare seeking behaviors of Beijing residents in the wake of the worldwide epidemic of the novel 2009 H1N1 influenza virus, and potential changes in these behaviors during a full-blown pandemic. METHODS: We used a two-stage Mitofsky-Waksberg telephone survey to collect information for Beijing residents >/= 18 years of age and weighted the sample by the census estimate of Beijing population for 2008. A structured questionnaire was used to collect information about the respondents' knowledge regarding the novel influenza virus, current personal protective and healthcare seeking behaviors during a full-blown influenza pandemic. RESULTS: 286 Beijing urban residents were interviewed during May 15 to 18 (response rate: 62%). 77% (95%CI: 71% - 82%) of the residents that they would cover their sneezes at home, and 93% (95%CI: 89% - 96%) would do so in a public place. Of the residents would cover their sneezes at home, 66% (95%CI: 57% - 74%) would covered their sneezes by hand, 33% (95%CI: 25% - 42%) by facial tissue, and only 0.4% (95%CI: 0.1% - 2.9%) by sleeves. Similarly, of the residents would cover their sneezes at a public place, 64% (95%CI: 56% - 71%) would cover their sneezes by hand, 33% (95%CI: 26% - 41%) by facial tissue and 0% by sleeves. 46% (95%CI: 32% - 59%) of the residents would wash their hands after covering their sneezes with hand in public places, and 77% (95%CI: 64% - 89%) would do so at home. Higher percentages of residents would wear a mask (63%, 95%CI: 56% - 70%) and get vaccinated (43%, 95%CI: 37% - 50%) during a pandemic than under currently situation (3.5%, 95%CI: 1.7% - 7.0% for wearing a mask; 13%, 95%CI: 9.8% - 18% for getting vaccinated). 86% (95%CI: 81% - 89%) of the residents would visit a doctor for an influenza-like illness during a pandemic, similar to the percentage currently seen (76%, 95%CI: 70% - 81%). 71% (95%CI: 63% - 78%) of the residents would visit a doctor for influenza-like illness and would choose a tertiary medical center; with percentage (74%, 95%CI: 66% - 80%) similar to the one during a pandemic. CONCLUSION: Beijing residents need to be aware of the proper ways to cover their noses when sneezing (especially using their sleeves more), and to wash their hands. An effective plan to triage patients should be immediately established to efficiently utilize the limited healthcare resources, which would likely be further strained during a pandemic.

Genome-wide linkage scan for colorectal cancer susceptibility genes supports linkage to chromosome 3q.

BACKGROUND: Colorectal cancer is one of the most common causes of cancer-related mortality. The disease is clinically and genetically heterogeneous though a strong hereditary component has been identified. However, only a small proportion of the inherited susceptibility can be ascribed to dominant syndromes, such as Hereditary Non-Polyposis Colorectal Cancer (HNPCC) or Familial Adenomatous Polyposis (FAP). In an attempt to identify novel colorectal cancer predisposing genes, we have performed a genome-wide linkage analysis in 30 Swedish non-FAP/non-HNPCC families with a strong family history of colorectal cancer. METHODS: Statistical analysis was performed using multipoint parametric and nonparametric linkage. RESULTS: Parametric analysis under the assumption of locus homogeneity excluded any common susceptibility regions harbouring a predisposing gene for colorectal cancer. However, several loci on chromosomes 2q, 3q, 6q, and 7q with suggestive linkage were detected in the parametric analysis under the assumption of locus heterogeneity as well as in the nonparametric analysis. Among these loci, the locus on chromosome 3q21.1-q26.2 was the most consistent finding providing positive results in both parametric and nonparametric analyses Heterogeneity LOD score (HLOD) = 1.90, alpha = 0.45, Non-Parametric LOD score (NPL) = 2.1). CONCLUSION: The strongest evidence of linkage was seen for the region on chromosome 3. Interestingly, the same region has recently been reported as the most significant finding in a genome-wide analysis performed with SNP arrays; thus our results independently support the finding on chromosome 3q.

DNA mismatch repair gene hMLH3 variants in meiotic arrest.

Defects of the DNA mismatch repair gene hMLH3 were screened by denaturing high-performance liquid chromatography and sequencing in germinal tissue DNA from patients with spermatogenic arrest, with sequence variations being confirmed in genomic DNA by polymerase chain reaction (PCR) direct sequencing analysis. Four missense (2896T/C, 2531C/T) and eight intronic (IVS9+66G/A) variants were found, with the combination of 2531C/T and IVS9+66G/A being identified only in patients with primary meiotic arrest, thus suggesting that two simultaneous hMLH3 variants might predispose to spermatogenic arrest.