AP2α controls the dynamic balance between miR-126&126* and miR-221&222 during melanoma progression.

Accumulating evidences have shown the association between aberrantly expressed microRNAs (miRs) and cancer, where these small regulatory RNAs appear to dictate the cell fate by regulating all the main biological processes. We demonstrated the responsibility of the circuitry connecting the oncomiR-221&222 with the tumor suppressors miR-126&126* in melanoma development and progression. According to the inverse correlation between endogenous miR-221&222 and miR-126&126*, respectively increasing or decreasing with malignancy, their enforced expression or silencing was sufficient for a reciprocal regulation. In line with the opposite roles of these miRs, protein analyses confirmed the reverse expression pattern of miR-126&126*-targeted genes that were induced by miR-221&222. Looking for a central player in this complex network, we revealed the dual regulation of AP2α, on one side directly targeted by miR-221&222 and on the other a transcriptional activator of miR-126&126*. We showed the chance of restoring miR-126&126* expression in metastatic melanoma to reduce the amount of mature intracellular heparin-binding EGF like growth factor, thus preventing promyelocytic leukemia zinc finger delocalization and maintaining its repression on miR-221&222 promoter. Thus, the low-residual quantity of these two miRs assures the release of AP2α expression, which in turn binds to and induces miR-126&126* transcription. All together these results point to an unbalanced ratio functional to melanoma malignancy between these two couples of miRs. During progression this balance gradually moves from miR-126&126* toward miR-221&222. This circuitry, besides confirming the central role of AP2α in orchestrating melanoma development and/or progression, further displays the significance of these miRs in cancer and the option of utilizing them for novel therapeutics.

Oncogenic HoxB7 requires TALE cofactors and is inactivated by a dominant-negative Pbx1 mutant in a cell-specific manner.

The homeobox containing gene HoxB7 is functionally associated with melanoma growth promotion through the direct transactivation of bFGF. Accordingly, the introduction of HoxB7 in the breast cancer line SkBr3 (SkBr3/B7), strongly increases its tumorigenic properties. Here we show that in SkBr3/B7 cells, HoxB7 regulates the expression of TALE Hox cofactors by increasing Pbx2 and Prep1 and decreasing Pbx1. The functional requirement of Hox cofactors in the oncogenic activity of HoxB7 was proven with a dominant-negative Pbx1 mutant, Pbx1NT, which sequesters Prep1 in the cytoplasm. The less aggressive phenotype of the SkBr3/B7/PbxNT cells, evaluated in vitro as well as in vivo, correlated well with increased apoptosis, decreased cycling and up-regulation of p16 and p53. Tumor cell-type specific functional effects of Pbx1NT were observed, possibly related to the presence of different Hox genes in melanoma or breast adenocarcinoma DNA-protein ternary complexes.

Laparoscopic transabdominal preperitoneal (TAPP) hernia repair: surgical phases and complications.

BACKGROUND: This study aimed to determine the nature of complications after transabdominal preperitoneal (TAPP) hernia repair, and to evaluate possible links to intraoperative factors in an effort to reduce the incidence of complications. METHODS: The TAPP procedures for inguinal/femoral hernias performed between 1992 and 2004 at a single center were analyzed retrospectively. Complications were categorized according to severity and stage of the surgical procedure at which they occurred. Individual surgeon performances were examined to determine whether the rates of complications were related to surgeon experience. RESULTS: A total of 1,973 TAPP procedures were reviewed, and 81% of the patients completed 5 years of follow-up evaluation. The 74 complications (3.7%) reported were categorized as follows: 33 major (1.7%) versus 41 minor (2.0%), 66 hernia-related (3.4%) versus 8 laparoscopy-related (0.5%) complications, and 12 recurrences (0.6%). Risk factors for complications included inguinoscrotal hernia (p < or = 0.001), dissection/reduction of the sac (p = 0.02), and surgeon experience (< 50 TAPP procedures; odds ratio, 7.1; 95% confidence interval, 4.2-11.9). CONCLUSIONS: Accuracy in dissection/reduction of the sac improves the outcome of TAPP hernia repair. This effect is related to the experience of the surgeon. Experience performing more than 75 procedures is required for optimal results.

HOXB7: a key factor for tumor-associated angiogenic switch.

We had demonstrated previously a functional bridge between altered homebox (HOX) gene expression and tumor progression through HOXB7 transactivation of basic fibroblast growth factor. Here, we have studied whether HOXB7, in addition to basic fibroblast growth factor, may induce other genes directly or indirectly related to neoangiogenesis and tumor invasion. Parental, beta-galactosidase-transduced, and HOXB7-transduced SkBr3 cell lines were examined for the expression of several growth factors and growth factor receptors involved in the proliferative and angiogenic processes. Vascular endothelial growth factor, melanoma growth-stimulatory activity/growth-related oncogenene alpha, interleukin-8, and angiopoietin-2 were up-regulated by HOXB7 transduction. The exception was angiopoietin-1 expression that was abrogated. Additional analyses included the expression levels of enzymes such as matrix metalloprotease (MMP)-2 and MMP-9 and heparanase, capable of proteolytic degradation of extracellular matrix and basement membranes. Results showed an induction of only MMP-9. The functional implication of such a finding was tested using an in vitro coculture assay in a three-dimensional matrix. A delay of differentiation with persistent nests of proliferating cells was found in endothelial cells cocultured with HOXB7-transduced SkBr3 cells. Tumorigenicity of these cells has been evaluated in vivo. Xenograft into athymic nude mice showed that SkBr3/HOXB7 cells developed tumors in mice, either irradiated or not, whereas parental SkBr3 cells did not show any tumor take unless mice were sublethally irradiated. Comparison of tumor nodules for vascularization by CD-31 and CD-34 immunostaining revealed an increased number of blood vessels in tumors expressing HOXB7. Together, the results indicate HOXB7 as a key factor up-regulating a variety of proangiogenic stimuli. Thus, HOXB7 gene or protein is a target to aim at to inhibit tumor-associated neoangiogenesis, considering the number and the redundancy of proangiogenic molecules that should be targeted one by one to theoretically achieve the same effect.

[Effect of brachial-radial and extensor carpi radialis longus tenodesis on elbow flexion-extension movements. Application to tendon transfers in tetraplegia]. / Mesure sur le brachio-radialis et l'extensor carpi radialis longus de l'effet ténodèse lié aux mouvements de flexion-extension du coude. Application aux transferts tendineux chez le tétraplégique.

The authors show that extension of the elbow produces a traction on brachioradialis (BR) and extensor carpi radialis longus (ECRL): if their tendon is distally freed, it is pulled in the proximal direction when the elbow extends. This phenomenon provides tenodesis effects, especially after tendon transfer in tetraplegia. It has been assessed on 31 upper limbs of patients and fresh cadavers. The mean tendon excursion, between 90 degrees flexion and full extension of the elbow, was 32 mm for BR and 19 mm for ECRL. These tenodesis effects related to the extension of the elbow leads the authors to recommend three practices in tetraplegic patients: active extension of the elbow should be restored before rehabilitation of the hand, and a 90 degrees flexion of the elbow is the position in which BR and ECRL transfers should be set intraoperatively, as well as immobilized postoperatively.

[Isokinetic dynamometric evaluation of rehabilitation results of elbow extension in tetraplegic patients]. / Evaluation par dynamomètre isocinétique des résultats de la réanimation de l'extension du coude chez le tétraplégique.

The authors designed a protocol to assess isokinetic muscle strength of elbow in tetraplegic patients after rehabilitation of elbow extension. Twenty-seven elbows from 16 patients were assessed, after deltoïd-to-triceps (10 cases) or biceps to triceps transfer (17 cases); the mean follow-up was 39 months. Seventeen elbows from 9 healthy individuals were also assessed. Regardless of the type of the transfer performed, the extension torque was on average much lower in the group of tetraplegic patients than in the control group, especially at the beginning of the movement. However the dynamic appearance of the curve of torque in extension was similar in the two groups. The mean flexion torque was on average very low after biceps-to-triceps transfer, especially at the end of the movement, but remained acceptable after deltoïd-to-triceps transfer.

[Anatomical study of the distal tendon of the brachial biceps muscle. Application to biceps-triceps transfer in tetraplegic patients]. / Etude anatomique du tendon distal du biceps brachial. Application au transfert biceps-triceps chez le tétraplégique.

In some cases of biceps-to-triceps transfer the muscle fibres of the biceps are inserted very distally, preventing correct setting of the transfer. A knowledge of the anatomy of the intramuscular part of the distal tendon of the biceps is useful to lengthen this tendon proximally. A study of 40 specimens showed that the intramuscular part of the distal tendon of the biceps is a large flattened lozenge-shaped aponeurosis located in a frontal plane. It receives muscle fibre insertions on both aspects. The length of the invisible part of the tendon can be estimated by a simple formula: 0.55 a + 4 cm, where "a" represents the length of the tendon between the most proximal tendinous point visible, and the most distal muscle point visible.

Functional outcome after surgery for trigonocephaly.

The long-term mental outcome of 76 children operated on for trigonocephaly was assessed, and the factors influencing the prognosis were studied. Final assessment of mental development was made on children who were more than 3 years old and was based on the occurrence of behavioral disturbances, learning disability, and school difficulties, and on intellectual efficiency. Children were graded into three groups: no abnormality, mild abnormalities but with normal social function, and grossly abnormal. Preoperative computed tomography scans were used to measure the severity of the frontal stenosis and to identify associated intracranial abnormalities, such as agenesis of the corpus callosum, dilatation of the subdural spaces, or hydrocephalus. Associated extracranial malformations and associated family cases were also noted. Lastly, the family setting was studied. Overall, 31.6 percent of patients had evidence of some degree of trouble. Several correlations were identified: mental development was worse when the frontal stenosis was severe, when cranial reconstruction was performed after 1 year of age, and when there were associated extracranial malformations. In addition, the family environment was found to have a major influence, but the presence of intracranial abnormalities did not correlate with mental development.

Organ culture in 3-dimensional matrix: in vitro model for evaluating biological compliance of synthetic meshes for abdominal wall repair.

A new in vitro method to evaluate the early critical interactions between synthetic prosthetic materials and growing tissues is reported. The correct spatial organization and proper cell to cell interaction required to mimic the in vivo environment was obtained in a 3-dimensional (3-D) embryo organ culture. The clot formed by plasma and chick-embryo extract provided a natural 3-D extracellular matrix that was able to support the growth and differentiation of intestinal tissue dissected from 12-day-old chick embryos. Different materials used for the repair of abdominal wall defects were taken as standards; all the prosthetic materials were devoid of any evident cytotoxic potential over a 10-day culture period, so they did not interfere with the organogenesis process. A polyglactin mesh (Vicryl) was fully incorporated into the growing tissue, but early signs of its degradation were detectable. The biologically inert materials polyethylene terephthalate (Mersilene) and polypropylene (Marlex, Prolene, and Herniamesh) retained their structural integrity when incubated with cultured tissue at 37 degrees C, and they did not hinder cellular proliferation or fibroblast migration. However, the outgrowth behavior was very different while the connective tissue invaded the interstices of the polyethylene terephthalate mesh; the explants and the migrating cells were repelled by hydrophobic polypropylene meshes. These findings are in agreement with other reported results in in vivo studies. Therefore, this method can be considered as reliable and predictable for the evaluation of biopolymers.

[Mental prognosis of trigonocephaly and therapeutic implications]. / Pronostic mental des trigonocéphalies et implications thérapeutiques.

The authors assessed the long-term mental prognosis of trigonocephaly, in a series of 76 operated cases. Mental prognosis factors were studied, showing that early cranial release and reconstruction were effective. Final assessment of mental development was performed on children of school age, and was based on the development of behavioral disturbances, learning disability, school difficulties, and intellectual efficiency. Children were graded into 3 groups: no abnormality, mild abnormalities with normal socialization, major abnormalities; 31.6% presented disorders. Preoperative C-T scans assessed the severity of the cranial deformity and identified associated intracranial abnormalities, such as agenesis of the corpus callosum, dilatation of the subdural spaces, or hydrocephalus. Associated extracranial malformations, and associated family cases were also noted. Finally, the quality of the family context was studied. Several correlations were identified; mental development was correlated with the severity of frontal stenosis, the age at surgery and the associated extracranial malformations. Family environment also had a major influence. Intracranial abnormalities were not correlated with mental development.

Antley-Bixler syndrome. Description of two new cases and a review of the literature.

Antley-Bixler syndrome was first described in 1975, and to date 20 cases have been reported. In addition to brachycephaly, the syndrome is associated with midface hypoplasia, often with choanal stenosis or atresia, bilateral radiohumeral synostosis, multiple joint contractures, femoral bowing and long bone fractures, "pear-shaped" nose, dysplastic ears and, occasionally, urogenital or cardiac defects. Survival is closely linked to upper airway obstruction. This, in addition to craniosynostosis, also affects mental prognosis. The cluster of malformations and their severity are variable, and while numerous children have died early from respiratory distress, one third of them are alive and have had quite satisfactory development. With early and effective prevention of respiratory complications and early treatment of craniosynostosis, the overall prognosis can be favorable. The mode of inheritance is probably autosomal recessive, and midtrimester prenatal diagnosis is feasible. Genetic counseling depends on accurate prognostic and therapeutic data. We describe two new cases, a 4-year-old boy with unilateral coronal synostosis and radiohumeral synostosis on the same side and an 18-month-old girl with brachycephaly and imperforate anus.

[Antley-Bixler syndrome. Description of two new cases and review of the literature. Prognostic and therapeutic aspects]. / Le syndrome d'Antley-Bixler. Description de deux nouveaux cas et revue de la littérature. Eléments pronostiques et thérapeutiques.

Antley-Bixler syndrome was first described in 1975, and to date, 20 cases have been reported. In addition to brachycephaly, the syndrome is associated with midface hypoplasia often with choanal stenosis or atresia, bilateral radiohumeral synostosis, multiple joint contractures, femoral bowing and long bone fractures, "pear-shaped nose", dysplasic ears, and occasionally urogenital or cardiac defects. Survival is closely linked to upper airway obstruction, which also affects (with craniosynostosis) mental prognosis. Association and severity of malformations are variable, and while numerous children have died early from respiratory distress, one third of them are alive, and have had quite satisfactory development. With early and effective prevention of respiratory complications, and early treatment of craniosynostosis, overall prognosis can be favorable. The mode of inheritance is probably autosomal recessive and midtrimester prenatal diagnosis is feasible; genetic counseling depends on accurate prognostic and therapeutic data. We describe 2 further cases. The first a 4 years old male, with unilateral coronal synostosis and radiohumeral synostosis predominating on the same side. The second an 18 months old female, with brachycephaly and an imperforate anus.

HOXB cluster genes in activated natural killer lymphocytes: expression from 3'-->5' cluster side and proliferative function.

The expression of HOXB cluster genes (i.e., B1 through B9) was evaluated in purified IL-2/IL-1 beta-activated NK lymphocytes from normal adult peripheral blood by RNase protection and reverse transcription-PCR. In quiescent NK cells these genes are essentially not expressed. After IL-2/IL-1 beta addition, we observed a coordinate induction wave in the 3'-5' HOXB cluster direction, i.e., from B1 through B9. As notable exceptions, B8 is silent, while B9 RNA is detected starting from 6 h through day 11. Furthermore, the 3' located B2/B3/B4 are expressed earlier and at higher level than the 5' located B5/B6/B7/B8. In IL-2/IL-1 beta-activated NK cells, treatment with antisense oligonucleotides targeting B2 mRNA causes a significant inhibition of both cell proliferation and expression of activation markers (i.e., IL-2R alpha-chain and transferrin receptor). These studies provide novel evidence of the role of HOX genes in adult NK cell proliferation. Thus, 1) a coordinate activation of HOXB genes from the 3'-->5' cluster side apparently underlies IL-2/IL-1 beta-induced NK cell activation. 2) Since NK cell activation and survival induced by IL-12 and c-kit ligand, respectively, are not associated with cell proliferation of HOXB gene expression, it is apparent that HOXB gene induction is specifically associated with IL-2-induced NK cell proliferation. 3) Studies with antisense oligomer targeting HOXB2 mRNA suggest an important role for 82 in NK cell proliferation, possibly in part via the IL-2R.

[Recurrent inguinal hernia. Propositions of classification and surgical strategy]. / Hernies récidivées de l'aine. Propositions de classification et de tactique chirurgicale.

We reviewed 1005 cases of groin hernia in 932 patients including 113 recurrent hernias. Eighty-seven percent of the patients were seen again one year after surgery for an evaluation of technique, results and complications. The data obtained was used to propose a simple anatomoclinical classification into three types which could be used to orient surgical strategy. Type R1 includes first relapse oblique external reducable hernia of less than 2 cm in non-obese patients: the Lichtenstine-gilbert technique is indicated. Type R2 includes inferior, direct reducable first relapse hernia of less than 2 cm in non-obese patients: the Wantz-Trabucco technique is indicated. Type R3 includes all the other forms: the Stoppa technique, or alternatively laparoscopy, is proposed.

[Use of polypropylene (Marlex) prosthesis in the surgical treatment of inguinal and crural hernia]. / L'uso delle protesi in polipropilene (Marlex) nel trattamento chirurgico dell'ernia inguinale e crurale.

High biocompatibility, low cost and easiness in use are most important reasons for the spread of biological prosthesis in inguinal and femoral hernia repairs; this fact has changed the surgical approach to this kind of pathologies. This new approach consists in re-creating a normal anatomic function of the abdominal wall, without new tension between muscles and aponeurotic structures. The authors present their experience after 379 inguinal and femoral hernia repairs between January 1992 and December 1993.

Cell cycle-dependent initiation and lineage-dependent abrogation of GATA-1 expression in pure differentiating hematopoietic progenitors.

The programmed activation/repression of transcription factors in early hematopoietic differentiation has not yet been explored. The DNA-binding protein GATA-1 is required for normal erythroid development and regulates erythroid-expressed genes in maturing erythroblasts. We analyzed GATA-1 expression in early human adult hematopoiesis by using an in vitro system in which "pure" early hematopoietic progenitors are induced to gradual and synchronized differentiation selectively along the erythroid or granulocyte-macrophage pathway by differential treatment with hematopoietic growth factors. The GATA-1 gene, though virtually silent in quiescent progenitors, is activated after entrance into the cell cycle upon stimulation with hematopoietic growth factors. Subsequently, increasing expression along the erythroid pathway contrasts with an abrupt downregulation in the granulocyte-macrophage lineage. These results suggest a microenvironment-directed, two-step model for GATA-1 expression in differentiating hematopoietic progenitors that involves (i) cycle-dependent initiation and (ii) lineage-dependent maintenance or suppression. Hypothetically, on/off switches of lineage-restricted transactivators may underlie the binary fate decisions of hematopoietic progenitors.

Molecular mechanisms underlying the expression of the human HOX-5.1 gene.

The complex mechanisms underlying homeobox genes expression involve regulation at transcriptional, post-transcriptional and translational levels. The multiple transcripts of the human HOX-5.1 gene are expressed differentially in tissue- and stage-specific patterns during embryogenesis, and differentially induced by retinoic acid (RA) in human embryonal carcinoma (EC) NT2/D1 cells. We have sequenced 6.3 Kb of the genomic region containing the HOX-5.1 gene and analyzed its mechanisms of expression. Two alternative promoters underlie the transcription of two classes of HOX-5.1-specific mRNAs. These classes differ in tissue and subcellular distribution, induction by RA, structure of the 5'-UT region and mRNA stability: these features are compatible with a differential function of the two classes of transcripts in embryogenesis.

Constitutive expression and abnormal glycosylation of transferrin receptor in acute T-cell leukemia.

The expression of transferrin receptors (TrfRs) was investigated in acute T-cell leukemia (T-ALL) blasts at the molecular, biochemical, immunological, and functional level. TrfRs, although not detected on quiescent T-cells from normal adults, are constitutively expressed at high level on the blasts from all T-ALL patients and bind normally to transferrin. Their number is modulated by the intracellular iron level, but is independent of exogenous interleukin 2. They also exhibit immunological and biochemical abnormalities, in that: (a) they react preferentially with monoclonal antibodies (MAb) that recognize ligand-binding domains of TrfR (42/6 and 43/31), as compared to MAbs (B3/25, OKT9) that interact with the nonligand binding domains; (b) they have a reduced molecular weight, as compared to TrfR on normal thymocytes and activated T-lymphocytes: this phenomenon is apparently related to a defective glycosylation. It is noteworthy that expression of TrfR was not observed in a large series of other types of acute leukemias, i.e., pre-B, B, and myeloid leukemias, excluding erythroleukemias. The constitutive, high level expression of TrfRs on T-ALL blasts may play a key role in the stepwise progression of this malignancy and particularly provide a proliferative advantage to T-ALL blasts as compared to normal T-lymphocytes. Furthermore, indirect evidence suggests that the glycosylation defect of TrfR on T-ALL blasts contributes to their tumorigenic capacity.

Expression of protein kinase C genes during ontogenic development of the central nervous system.

We have analyzed the RNA expression of three protein kinase C (PKC) genes (alpha, beta, and gamma) in human and murine central nervous systems during embryonic-fetal, perinatal, and adult life. Analysis of human brain poly(A)+ RNA indicates that expression of PKC alpha and beta genes can be detected as early as 6 weeks postconception, undergoes a gradual increase until 9 weeks postconception, and reaches its highest level in the adult stage, and that the PKC gamma gene, although not expressed during embryonic and early fetal development, is abundantly expressed in the adult period. Similar developmental patterns were observed in human spinal cord and medulla oblongata. A detailed analysis of PKC gene expression during mammalian ontogeny was performed on poly(A)+ RNA from the brain cells of murine embryos at different stages of development and the brain cells of neonatal and adult mice. The ontogenetic patterns were similar to those observed for human brain. Furthermore, we observed that the expression of PKC gamma is induced in the peri- and postnatal phases. These results suggest that expression of PKC alpha, beta, and gamma genes possibly mediates the development of central neuronal functions, and expression of PKC gamma in particular may be involved in the development of peri- and postnatal functions.