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PubMed2003

11q23-24 loss is associated with chromosomal instability in endometrial cancer.

A loss of the DNA copy number at chromosomal region 11q23-24 as detected by comparative genomic hybridization (CGH) is a marker of poor prognosis in patients with endometrial cancer. Malignant tumors display genetic instability, which is classified into two types: microsatellite instability (MIN) and chromosomal instability (CIN). In the present study, we examined whether there is a relation between loss of 11q23-24 and genetic instability in endometrial adenocarcinoma. Loss of 11q23-24 was detected in 4 of 70 endometrial cancers by fluorescence in situ hybridization (FISH), and DNA aneuploidy was detected by laser scanning cytometry (LSC) in 14 tumors. All tumors with 11q23-24 loss were aneuploid, and three of them were considered to have CIN. These findings suggest that 11q23-24 contains gene(s) necessary for normal chromosome replication and cell division.

Adult↗
PubMed1992

Lunate-triquetral and midcarpal joint instability.

Instability of the ulnar side of carpus centers around the triquetrum, which is suspended by the ulnar triquetral ligaments and supported proximally by the TFCC. The triquetrum guides the lunate by an interosseous membrane and stout palmar ligaments that provide a relatively rigid connection between the two bones. Disruption of the LT ligament is frequently associated with pathology in the ulnar carpal area and may progress to triquetral instability, VISI, and finally, degenerative arthritic changes on the ulnar side of the carpus. The diagnosis of LT injuries is made by stress radiographs, arthrography, video-fluoroscopy, and arthroscopy. Treatment is initially nonoperative, but if symptoms persist, surgery is warranted. Arthroscopic debridement and pinning the LT joint, ligament repair or reconstruction, and intercarpal arthrodesis have all been reported as successful treatments. For the chronic problem confined to the LT joint, a limited intercarpal arthrodesis of the joint is the most predictable procedure for relieving pain without causing any significant restrictions in wrist motions. When there is a dissociation pattern in addition to LT instability, a more extensive intercarpal arthrodesis is required. Midcarpal instability occurs at the triquetral-hamate joint and is characterized by a dynamic subluxation of the joint. During ulnar deviation, the joint undergoes an exaggerated shift from volar flexion to dorsiflexion. Supportive care is generally successful; although in chronic cases, a midcarpal joint arthrodesis is often required.

Arthrodesis↗
PubMed2003

Magnetic resonance imaging in diagnosis of chronic posterolateral rotatory instability of the elbow.

Posterolateral rotatory instability of the elbow can be difficult to diagnose and requires a high degree of clinical suspicion. Cases of chronic posterolateral rotatory instability (symptoms present more than 1 year) may be an even more perplexing subgroup. This is a case report of a patient with a 30-year history of intermittent elbow instability. Clinical examination was equivocal, and magnetic resonance imaging was unable to define any ligamentous injury around the elbow. Examination under anesthesia and surgical findings were consistent with complete disruption of the lateral ulnar collateral ligament. The 12-month follow-up after surgical reconstruction showed complete resolution of symptoms. Posterolateral rotatory instability is a diagnosis largely made by examination under anesthesia. A thorough history and a high clinical suspicion are necessary to support the physician's decision to place the patient under anesthesia. Confirmation of a chronic tear of the lateral ulnar collateral ligament of the elbow with magnetic resonance imaging can be difficult and sometimes misleading.

Adult↗
PubMed2003

[Treatment of degenerative lumbar spine instability with transpedical screw fixation and intertransverse process autogenous bone grafting].

OBJECTIVE: To observe the early clinical results with degenerative lumbar instability treated with transpedical screw fixation and intertransverse process autogenous bone grafting. METHODS: From September 2000 to February 2002, 19 patients (5 males and 14 females) of degenerative lumbar spine instability were treated with decompression for spinal canal stenosis, transpedical screw fixation and intertransverse process autogenous bone grafting. The locations of degenerative lumbar spine instability were between L4 and L5 in 10 patients, between L3, L4 and L5 in 4 cases, between L3 and L4 in 3 cases, between L5 and S1 in 2 cases. The results were evaluated after operation. The preoperative clinical symptoms disappeared completely as excellent results, relieved obviously as good results, improved as fair results and unrelieved or worsened as poor results. RESULTS: Seventeen patients were followed up for 4-18 months with an average of 8.1 months. The results of the treatment were excellent in 12 patients, good in 4 patients and fair in 1 patient. The excellent and good rate was 94.1%. Intertransverse process arthrodesis was obtained after 6 months of operation in all cases. No loosened and broken instruments occurred. CONCLUSION: The advantages of degenerative lumbar spine instability treated with transpedical screw fixation and intertransverse are reliable fixation, high successful rate of fusion and less influence on spinal canal. The above results show satisfactory clinical outcome.

Bone Screws↗
PubMed2003

[Manifestation of glutathione S-transferase GSTM1 and GSTT1 in female patients with bleomycin-positive chromosome instability].

OBJECTIVES: The purpose of this research is to assess the incidence of gene polymorphisms coding the GSTM1 and GSTT1 enzymes in a population of female patients with chromosome instability. MATERIALS AND METHODS: The PCR method was used to determine the genotype for GSTM1 and GSTT1. The breaks per cell and the percentage of damaged cells were calculated. The separation point used to diagnose chromosome instability in tested females was assumed to be 2.5. RESULTS: In a tested population of 85 females with chromosome instability, the deletion of both the alleles of the GSTT1 gene was observed in 22 females (25% of the group) and deletion of both the alleles of the GSTM1 gene was observed in 42 females (53% of the group). In addition, the incidence of individual genes was calculated for the tested population. The X2 test showed that the differences between the observed and expected values of the tested genes were statistically immaterial, i.e. the likelihood of randomness for these differences exceeded 99%. CONCLUSIONS: No relationship between the manifestation of genotypes for the GSTM1 and GSTT1 glutathione S-transferases and an increased chromosome instability confirmed with the bleomycin test was proven for a population of females with a neoplastic risk.

Adult↗
PubMed2003

Hyper-recombination and genetic instability in BLM-deficient epithelial cells.

Genetic instability appears to be required for a normal colorectal epithelial cell to evolve into a cancerous one. Bloom syndrome patients have a strong predisposition to cancer that affects a variety of tissues. The mechanism of disease is attributed to genomic instability, but many questions about the nature of this instability have not yet been answered. To investigate these issues, we used gene-targeting techniques to disrupt the BLM gene in karyotypically stable colorectal cancer epithelial cells. BLM knockout cells showed an increased tendency of sister chromatids to exchange DNA strands and were substantially more likely to undergo homologous recombination at chromosomal loci than parental cells. Surprisingly, BLM-deficient colorectal cancer epithelial cells did not display gross chromosomal rearrangements nor a change in the rates of chromosome gains and losses. However, the enhanced homologous recombination was associated with losses of heterozygosity. These observations define a type of genetic instability that has significant implications for the evolution of cancer.

Adenosine Triphosphatases↗
PubMedDate not supplied

[Prognostic significance of chromosome and microsatellite instability in colorectal cancer].

The prediction of recurrence and the prognosis of colorectal cancer have always been related to the stage of the disease. Clinical pathological classifications are unable to predict the individual risk of recurrence and the prognosis which would also appear to be linked to additional factors, which have yet to be properly assessed, such as the genetic endowment of the tumour. In this study we assessed how microsatellite and chromosomal instability may help us to stratify two classes of risk of recurrence in patients at the same stage. From July 1996 to June 1999 we prospectively collected data on 112 patients (59 male, 53 female) affected by colorectal cancer and undergoing surgery with a radical intent. Biopsies of normal and tumor tissue were submitted to DNA extraction and amplification to evaluate the presence of chromosomal instability (loss of heterozygosity) and microsatellite instability. Analysis of the data revealed that loss of heterozygosity in the long arm of chromosome 18 is associated, in patients with stage III colorectal cancer, with a higher risk of recurrence and therefore with a worse prognosis. Microsatellite instability proved to be associated with a better prognosis even in cases of recurrence.

Aged↗
PubMed2004

[Crystalline nickel sulfide-induced genomic instability in transformed human broncho-epithelial cells].

OBJECTIVE: To detect the genomic instability in the 16 human broncho-epithelial (16HBE) cells induced by crystalline nickel sulfide so as to provide the scientific basis for further study of nickel-induced cancer molecular mechanism. METHODS: To analyse the genomic instability in transformed 16HBE cells induced by crystalline nickel sulfide by random amplified polymorphic DNA (RAPD). RESULTS: All the 7 random primers selected could amplify 1 - 6 clear PCR bands. There were no significant differences between transformed 16HBE cells and negative control cells in the 4th, 5th, and 7th primers, but in the rest 4 primers there were significant differences, with special PCR bands for the same primer, indicating that genomic instability in transformed 16 HBE cells was induced by crystalline nickel sulfide. CONCLUSION: Crystalline nickel sulfide could induce genomic instability in 16HBE cells.

Cell Line, Transformed↗
PubMed2004

[Post-traumatic anterior shoulder instability--arthroscopic stabilization method using bone anchors].

PURPOSE OF THE STUDY: To evaluate the short-term results of re-insertion of the ventral labrum associated with plication of the capsular structures in anterior post-traumatic instability of the shoulder. MATERIAL: The patients treated in our institution between April 2000 and December 2002 and followed up for periods ranging from 3 to 20 months were included. A total of 65 patients were treated for post-traumatic ventral instability. Open capsular shift, after a final evaluation of preoperative examination under total anesthesia and arthroscopic inspection of the labroligamentous complex affected, was used in four patients. Arthroscopic stabilization was carried out in 49 men and 12 women, aged 18 to 49 years (average, 28.5). These patients were allocated to groups according to the number of previous dislocations as follows: group 1 (24 patients), one to five dislocations; group 2 (27 patients) six to ten dislocations; and group 3 (10 patients) 11 and more dislocations. The glenohumeral joint was inspected arthroscopically to find out potential lesions and evaluate them in relation to the number of previous dislocations. METHODS: Stabilization was carried out by means of non-absorbable anchors. It involved re-insertion of the ventral labrum and plication of the ventral capsular structures. The patients were evaluated on the basis of a modified system of Rowe and Zarins. RESULTS: In group 1, the anterior labrum or capsule showed only isolated lesions; most injury-related lesions were found in group 3. With the increasing number of dislocations, there was an increase in associated findings and severity of injury to the labroligamentous complex. The average score before the operation was 37.87 points (range, 20 to 60). After rehabilitation was completed, 57 (93.44%) patients scored good or excellent (70 or more points), with 29 (47.54%) having over 90 points; only four (6.56%) patients scored less than 70 points. Fifty-seven patients resumed their previous sports and four patients carried on with recreational sports activities. DISCUSSION: Open stabilization has been reported as being slightly more effective in maintaining stability, as compared with arthroscopic procedures. The major advantages of arthroscopy include a good view of the intra-articular structures, minimal invasiveness and less restricted range of postoperative motion. However, the arthroscopic stabilization technique becomes more difficult with an increasing number of dislocations sustained before this procedure. The ventral structures of the shoulder joint, known as labroligamentous complex, should be regarded in their complexity and anterior stability should be achieved both by re-insertion or adaptation of the glenoid labrum and by stretching the capsular structures, particularly the inferior glenohumeral ligament. Studies reporting a high degree of recurrence after the initial dislocation in subjects aged 20 to 30 years are discussed. In top, active sportsmen and sportswomen, stabilization after the first dislocation followed by instability appears to be a very effective therapy. CONCLUSIONS: Arthroscopic stabilization with the use of non-absorbable anchors for the treatment of anterior post-traumatic instability of the humeral joint is a method that, in indicated cases assessed mainly by mobility of the labrum and laxity of the anterior capsule, shows a high success rate. Indications are based on medical histories, clinical and radiographic findings and, most importantly, clinical tests under total anesthesia and arthroscopic confirmation of lesions of the ventral structures of the joint.

Adolescent↗
PubMed2004

Genomic instability in cancer: biological and mathematical approaches.

Genomic instability occurs in a majority of cancers. It manifests itself in a large number genetic alterations in cancer cells, such as small scale mutations, losses and gains of whole chromosomes and parts of chromosomes and mitotic recombinations. The role of genomic instability is still unknown. It is difficult to study because of its heterogeneous nature. Most methods based on looking for defined features of genes or gene expressions, are not applicable for unstable populations of cells. A variety of approaches are used to study genomic instability. These include experimental studies of cancer cell lines and mouse models, analysis of large amounts of data on loss of heterozygocity, and mathematical modeling of the relevant processes. We describe these approaches here; integration of different methods can improve our understanding of genomic instability.

Aging↗
PubMed2005

High grade sarcomas are associated with microsatellite instability (chromosom 12) and loss of heterozygosity (chromosom 2).

BACKGROUND: The genetic changes in DNA microsatellites - short, tandem repeat segments dispersed throughout the human genome - probably play a role in carcinogenesis. Microsatellite instability (MSI) is reflected in alterations in the patterns of these polymorphic repeat segments. In our study, human sarcomas were analyzed for the presence of microsatellite instability and loss of heterozygosity (LOH). MATERIAL/METHODS: Studies were performed on tissue specimens obtained at surgical resection from 20 patients with malignant and non-malignant soft tissue tumors (8 G1 sarcomas, 8 G3 sarcomas, 2 lipomas and 2 fibromas). Samples of venous blood from the patients served as respective controls. DNA was isolated using organic extraction. Additional microcolumn purification was performed. Fluorescent multiplex polymerase chain reaction (PCR) was used to amplify 10 microsatellite loci included in commercially available human identification kits. Microsatellite marker BAT 26 was amplified in separate PCR reactions. RESULTS: All the G3 sarcomas manifested MSI. MSI was detected on 12p in all the specimens except for recurrent synovial sarcomas. LOH in BAT 26 analysis (chromosome 2) was present in 75% of G3 sarcomas. No MSI or LOH was found in G1 sarcomas or in benign tumors. CONCLUSIONS: Genomic instability may contribute to tumorgenesis in sarcomas, and both MSI and LOH may reflect genomic instability in sarcomas. These parameters may be helpful in the differential diagnosis of malignant versus nonmalignant lesions.

Chromosomes, Human, Pair 12↗
PubMed2004

[Reconstruction of humeral head retroversion in the treatment of anterior shoulder instability].

Reduction of the physiologic retroversion of the humeral head can lead to shoulder luxation. After shoulder luxation it can also lead to shoulder instability. The aim of the paper was to check the level of humeral head retroversion in patients with anterior shoulder instability and to estimate the effectiveness of treatment of this instability with the derotational Weber osteotomy. The study included 38 patients, 34 males and 4 females, ranged 16-48 yr. (mean 31) treated in our Clinic. Every patient was done CT in order to estimate the level of humeral head retroversion. Patients with reduced humeral head retroversion qualified for operational treatment with Weber method derotational osteotomy. The outcomes were estimated according to the Rowe and Zarins score. 34 patients had excellent or good results. Pain was retreated, patients could come back to their normal activities, before the first luxation. Only 4 patients had another luxation in spite of our treatment. The control CT showed that the humeral head retroversion was 30 or more degrees. The arthroscopy was performed, the Bankart lesion was found and the patients were qualified for treatment this lesion. Weber osteotomy could be the satisfactory method of treatment of anterior shoulder instability in patients with physiologic reduction of humeral head retroversion.

Adolescent↗
PubMed2005

Microsatellite instability (MSI) analysis in patients with endometrial cancer.

Microsatellite instability (MSI) seems to be important for the development of various human cancers including sporadic endometrial cancer. The aim of this study was evaluation of microsatellite instability in 20 postmenopausal women with endometrial adenocarcinoma in DNA samples obtained from cancer tissue and blood of the same patients. Control DNA was obtained from normal endometrial tissue (n=25). MSI was studied at five loci containing single- or dinucleotide repeat sequences and mapping to different chromosomal locations: BAT-25 (at locus 4q12), BAT-26 (2pl6), D2S123 (2pl6-p21), D5S346 (5q21-q22) and D17S250 (17q11.2-q12). No differences in the MSI frequencies between blood and cancer tissue obtained from patients were detected. The microsatellite instability status was significantly higher in endometrial cancer tissue [5/20 (25%)] as compared to control [3/25 (12%)] (p < 0.05). There were no significant differences between MSI presence in the subgroups assigned to the histological grades (p > 0.05). The results suggest that the microsatellite instability seems to be important in the development of sporadic endometrial cancer.

Adenocarcinoma↗
PubMed2005

[Shoulder instability: classification and methods of clinical examination].

The shoulder is a complex joint whose stability relies on both dynamic and static factors. Dysfunction of one of these components gives rise to shoulder problems. Diagnosis of shoulder instability depends on a detailed history and appropriate physical examination. Despite the presence of many tests, none has proved to be purely diagnostic for shoulder instability. Therefore, these tests should be regarded as a part of the diagnostic procedure rather than a referral to diagnosis itself. Tests performed to assess laxity and instability are different in nature; thus, positive laxity tests do not necessarily show instability unless supported by further evidence. The reliability of the tests for superior labrum anterior-posterior lesions has not been adequately validated by clinical studies and few anatomical studies have examined the effect of these tests on the superior labral complex.

Humans↗
PubMed2005

[Open surgical treatment of recurrent anterior instability of the shoulder].

Recurrent anterior gleonohumeral instability is the most frequent joint instability of the body. Because of the complex stability mechanisms and diverse instability patterns of the glenohumeral joint, most cases present with more than one anatomic cause. Thus, the treatment of recurrent anterior instability of the shoulder should be designed to treat these pathologies. Although arthroscopic repair has outweighed the use of open surgical methods especially for the first dislocations, recurrent dislocations still require open repair techniques to overcome capsular laxity accompanying a Bankart lesion.

Humans↗
PubMed2005

[Study on genetic instability of NM23H1 gene in Chinese with the epithelial ovarian tumor].

The aim of this study was to examine microsatellite instability (MSI) and loss of heterozygosity (LOH) of locus D17S396 on chromosome 17 and their influence on the expression of nm23H1 in the epithelial ovarian tumors, which may provide experimental basis for the mechanism of nm23H1 gene and tumor metastasis. Techniques such as DNA extraction from formalin-fixed paraffin-embedded tissues, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), ordinary silver stain were used to study MSI and LOH of locus D17S396. Envision immunohistochemistry and Leica-Qwin computer imaging techniques were used to assess the expression of nm23H1 gene. In our experiments, the frequency of heredity instability of malignant ovarian tumors was 40%, which is higher than that of borderline ovarian tumors, while there were no heredity instability occurred in benign ovarian tumors and normal ovarian tissue. Among 25 epithelial ovarian carcinomas, the frequency of LOH in lymph node metastasis cases (66.67%) was significantly higher than those without metastasis (10.53%). Moreover, the frequency of LOH was higher in FIGO stage III and IV than in stage I and II. However, the frequency of MSI showed no correlation with any clinicopathologic characteristics. The positive frequency of nm23H1 protein in the ovarian epithelial carcinoma and borderline tumors were 56.00% and 57.14%, respectively. They were both higher than those of the benign tumors and normal ovarian tissue. In the epithelial ovarian carcinomas, the positive frequency of nm23H1 protein in lymph node metastasis case was significantly lower than those without metastasis. FIGO stage III and IV also exhibited lower positive frequency of nm23H1 protein compared with stage I and II. Furthermore, there was no difference in nm23H1 protein expression intensity analyzed by computer imaging. In the epithelial ovarian carcinomas, the positive frequency of nm23H1 protein in LOH positive group was 0.00%, which is lower than that of LOH negative group (P < 0.01). The results indicated that the heredity instability of nm23H1 gene might be implicated in pathogenesis and progression of epithelial ovarian tumor. The occurrence of LOH might be the molecule marker of the deteriorism of ovarian tissue. Both MSI and LOH of nm23H1 gene controlled development of the epithelial ovarian tumor independently in different paths. LOH could inhibit the expression of nm23H1 in local tissue of the epithelial ovarian carcinoma, which endowed it with high aggressive and poor prognosis. Increasing the amount of nm23H1 protein expression could effectively restrain metastasis of the ovarian epithelial carcinoma and improve prognosis of patients.

Asian People↗
PubMed2006

Study of microsatellite instability in epithelial ovarian tumors.

OBJECTIVE: To evaluate the frequency of MSI in epithelial ovarian tumors and its relationship with clinicopathologic features. METHODS: Ninety fresh specimens of epithelial ovarian tumors, including 74 primary and 16 secondary tumors, were collected. Microsatellite analysis was carried out using 5 mono-and dinucleotide markers from the National Cancer Institute Consensus Panel by fluorescence-labeled polymerase chain reaction. RESULTS: Of 90 epithelial ovarian tumors analyzed, 18 demonstrated a high level of microsatellite instability (MSI-H), 30 demonstrated a low level of microsatellite instability (MSI-L), and the remaining 42 exhibited microsatellite stability (MSS). Frequency of microsatellite instability (MSI) at loci BAT-25 was higher than that at any other loci. No correlation was found between MSI level and patient age, tumor type, tumor differentiation (P>0.05). But the microsatellite instability-high phenotype correlates with clinical stage. It tended to occur more frequently in early-stage tumors (P=0.03). CONCLUSION: The frequent MSI in epithelial ovarian tumors suggests that it is an early event to involve in the development of epithelial ovarian tumors.

Adult↗
PubMed2006

Relationship of the methylenetetrahydrofolate reductase C677T polymorphism with microsatellite instability and promoter hypermethylation in sporadic colorectal cancer.

The methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is associated with the expression of a thermolabile enzyme with decreased activity that influences the pool of methyl-donor molecules. Several studies have reported an association between C677T polymorphism and susceptibility to colorectal cancer (CRC). Considering that methylation abnormalities appear to be important for the pathogenesis of CRC, we examined the correlation between the genotype of the MTHFR C677T polymorphism, hypermethylation of the promoter region of five relevant genes (DAPK, MGMT, hMLH1, p16(INK4a), and p14(ARF)), and microsatellite instability, in 106 patients with primary CRCs in Brazil. We did not find significant differences in the genotypic frequencies of the MTHFR C677T polymorphism when one or more loci were hypermethylated. However, we did find a significant excess of 677TT individuals among patients with CRC who had microsatellite instability. This strong association was independent of the methylation status of hMLH1 and of the biogeographical genomic ancestry of the patients. Although the mechanism responsible for the link between the C677T polymorphism and microsatellite instability was not apparent, this finding may provide a clue towards a better understanding of the pathogenesis of microsatellite instability in human colorectal cancer.

Biomarkers, Tumor↗