Gopalrao V.N. Velagaleti

Human umbilical cord matrix stem cells : Preliminary characterization and effect of transplantation in a rodent model of parkinson's disease

The umbilical cord contains an inexhaustible, noncontroversial source of stem cells for therapy. In the U.S., stem cells found in the umbilical cord are routinely placed into bio‐hazardous waste after birth. Here, stem cells derived from human umbilical cord Whartons Jelly, called umbilical cord matrix stem (UCMS) cells, are characterized. UCMS cells have several properties that make them of interest as a source of cells for therapeutic use. For example, they 1) can be isolated in large numbers, 2) are negative for CD34 and CD45, 3) grow robustly and can be frozen/thawed, 4) can be clonally expanded, and 5) can easily be engineered to express exogenous proteins. UCMS cells have genetic and surface markers of mesenchymal stem cells (positive for CD10, CD13, CD29, CD44, and CD90 and negative for CD14, CD33, CD56, CD31, CD34, CD45, and HLA‐DR) and appear to be stable in terms of their surface marker expression in early passage (passages 4–8). Unlike traditional mesenchymal stem cells derived from adult bone marrow stromal cells, small populations of UCMS cells express endoglin (SH2, CD105) and CD49e at passage 8. UCMS cells express growth factors and angiogenic factors, suggesting that they may be used to treat neurodegenerative disease. To test the therapeutic value of UCMS cells, undifferentiated human UCMS cells were transplanted into the brains of hemiparkinsonian rats that were not immune‐suppressed. UCMS cells ameliorated apomorphine‐induced rotations in the pilot test. UCMS cells transplanted into normal rats did not produce brain tumors, rotational behavior, or a frank host immune rejection response. In summary, the umbilical cord matrix appears to be a rich, noncontroversial, and inexhaustible source of primitive mesenchymal stem cells.

Position Effects Due to Chromosome Breakpoints that Map ∼900 Kb Upstream and ∼1.3 Mb Downstream of SOX9 in Two Patients with Campomelic Dysplasia

Campomelic dysplasia (CD) is a semilethal skeletal malformation syndrome with or without XY sex reversal. In addition to the multiple mutations found within the sex-determining region Y–related high-mobility group box gene (SOX9) on 17q24.3, several chromosome anomalies (translocations, inversions, and deletions) with breakpoints scattered over 1 Mb upstream of SOX9 have been described. Here, we present a balanced translocation, t(4;17)(q28.3;q24.3), segregating in a family with a mild acampomelic CD with Robin sequence. Both chromosome breakpoints have been identified by fluorescence in situ hybridization and have been sequenced using a somatic cell hybrid. The 17q24.3 breakpoint maps ∼900 kb upstream of SOX9, which is within the same bacterial artificial chromosome clone as the breakpoints of two other reported patients with mild CD. We also report a prenatal identification of acampomelic CD with male-to-female sex reversal in a fetus with a de novo balanced complex karyotype, 46,XY,t(4;7;8;17)(4qter→4p15.1::17q25.1→17qter;7qter→7p15.3::4p15.1→4pter;8pter→8q12.1::7p15.3→7pter;17pter→17q25.1::8q12.1→8qter). Surprisingly, the 17q breakpoint maps ∼1.3 Mb downstream of SOX9, making this the longest-range position effect found in the field of human genetics and the first report of a patient with CD with the chromosome breakpoint mapping 3′ of SOX9. By using the Regulatory Potential score in conjunction with analysis of the rearrangement breakpoints, we identified a candidate upstream cis-regulatory element, SOX9cre1. We provide evidence that this 1.1-kb evolutionarily conserved element and the downstream breakpoint region colocalize with SOX9 in the interphase nucleus, despite being located 1.1 Mb upstream and 1.3 Mb downstream of it, respectively. The potential molecular mechanism responsible for the position effect is discussed.

Fanconi anemia: myelodysplasia as a predictor of outcome.

The adverse potential of the development of myelodysplastic syndrome (MDS) in Fanconi anemia (FA) was examined in a retrospective study of 41 FA patients who had bone marrow morphology and chromosomes reviewed by a single group. Thirty-three patients had adequate cytogenetic studies, and 16 (48%) had one or more abnormal studies: nine initially, and seven more on follow-up. Cytogenetic clonal variation was frequent, including disappearance of clones, clonal evolution, and appearance of new clones. The estimated five-year survival with a cytogenetic clone is 0.40, compared to 0.94 without a clone. Morphologic myelodysplasia (MDS), independent of a cytogenetic clone, was found in 13/41 patients (32%). The estimated five-year survival with MDS is 0.09, versus 0.92 without MDS. Leukemia developed in three patients whose initial cytogenetic clones prior to leukemia were t(1;18), t(5;22) and monosomy 7; the one with t(1;18) also had MDS. Our results focus on marrow morphology, and suggest that morphologic MDS may be more important than classical cytogenetics in prediction of an adverse outcome.

Ossifying fibromyxoid tumor of soft parts: report of a case with novel cytogenetic findings

A slowly growing tumor of the left thenar region in a 40-year-old man had the classic features of an ossifying fibromyxoid tumor of soft parts, including an incomplete shell of lamellar bone; a center composed of nodular aggregates of small spindled, oval, and stellate cells in abundant myxoid stroma; and strong expression of vimentin, S-100, and neuron-specific enolase by the tumor cells. Clonal chromosomal abnormalities included loss of a chromosome 6, extra material of unknown origin attached to the long arm of chromosome 12, and an unbalanced translocation involving the short arm of a chromosome 6 and the long arm of a chromosome 14. The karyotype was interpreted as 45,XY, der(6;14)(p10;q10),add(12)(q24.3). The chromosomal abnormalities suggest osteochondroblastic rather than neuronal or schwannian lineage.

Cytogenetic findings in a case of nodular fasciitis of subclavicular region

We report a case of nodular fasciitis with a reciprocal translocation involving both homologues of chromosome 15 [46,XX,t(15;15)(q13;q25)]. This is the third case of nodular fasciitis with involvement of chromosome 15. Two genes that are involved in either wound healing and/or tumorigenesis have been mapped to chromosome 15. One of the genes, the keratinocyte growth factor or fibroblast growth factor 7 (KGF or FGF7) was mapped to the 15q22 region, which was involved in a cytogenetic rearrangement in one case of nodular fasciitis. KGF is implicated in wound healing, healing lung injuries and tumorigenesis of various cancers such as breast and prostate. The second gene involved is TRKC or NTRK3 mapped to the 15q25 region. TRKC is implicated in congenital fibrosarcoma, a benign proliferation of fibroblasts. The breakpoint and overexpression of the protein in our case further suggest a possible involvement of TRKC.

PKA/AMPK signaling in relation to adiponectin's antiproliferative effect on multiple myeloma cells

Obesity increases the risk of developing multiple myeloma (MM). Adiponectin is a cytokine produced by adipocytes, but paradoxically decreased in obesity, that has been implicated in MM progression. Herein, we evaluated how prolonged exposure to adiponectin affected the survival of MM cells as well as putative signaling mechanisms. Adiponectin activates protein kinase A (PKA), which leads to decreased AKT activity and increased AMP-activated protein kinase (AMPK) activation. AMPK, in turn, induces cell cycle arrest and apoptosis. Adiponectin-induced apoptosis may be mediated, at least in part, by the PKA/AMPK-dependent decline in the expression of the enzyme acetyl-CoA-carboxylase (ACC), which is essential to lipogenesis. Supplementation with palmitic acid, the preliminary end product of fatty acid synthesis, rescues MM cells from adiponectin-induced apoptosis. Furthermore, 5-(tetradecyloxy)-2-furancarboxylic acid (TOFA), an ACC inhibitor, exhibited potent antiproliferative effects on MM cells that could also be inhibited by fatty acid supplementation. Thus, adiponectin’s ability to reduce survival of MM cells appears to be mediated through its ability to suppress lipogenesis. Our findings suggest that PKA/AMPK pathway activators, or inhibitors of ACC, may be useful adjuvants to treat MM. Moreover, the antimyeloma effect of adiponectin supports the concept that hypoadiponectinemia, as occurs in obesity, promotes MM tumor progression.

A Rapid and Noninvasive Method for Detecting Tissue-Limited Mosaicism: Detection of i(12)(p10) in Buccal Smear from a Child with Pallister-Killian Syndrome

Pallister-Killian syndrome (PKS), a rare disorder, is characterized by tissue-limited or tissue-specific mosaicism. The characteristic chromosome abnormality associated with PKS is i(12p), which is seen predominantly in skin fibroblast cultures. Diagnosis of i(12p) has been carried out on buccal smears before and was shown to be an easy and feasible method. All previously published studies used alpha-satellite probes for the diagnosis and as such have several pitfalls. Our approach, using dual-color, locus-specific probes, has high specificity and sensitivity for the diagnosis of i(12p). Using statistical analysis, we have also confirmed that the signal pattern in interphase nuclei is consistent with isochromosome 12p.

Malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation (malignant triton tumor) with balanced t(7;9)(q11.2;p24) and unbalanced translocation der(16)t(1;16)(q23;q13)

Malignant peripheral nerve sheath tumors (MPNST) with skeletal muscle differentiation are termed malignant triton tumors. A case of malignant triton tumor arising in a patient without signs of neurofibromatosis with two consistent chromosomal abnormalities is described. The first was of a balanced translocation between the long arm of chromosome 7 and the short arm of chromosome 9. The second was an unbalanced rearrangement between chromosomes 1 and 16, leading to partial trisomy for the long arm of chromosome 1 and partial monosomy for the long arm of chromosome 16. Review of previous reports on chromosomal abnormalities in malignant triton tumors revealed consistent abnormalities involving chromosome 1, regardless of the presence or absence of neurofibromatosis. This finding may relate to the observed poor prognostic outcome in this type of sarcoma. Also unique to our case is the translocation involving 7q and 9p, both regions may play a role in MPNST.

Prenatal Diagnosis of a Fetus with Unbalanced Translocation (4;13)(p16;q32) with Overlapping Features of Patau and Wolf-Hirschhorn Syndromes

Wolf-Hirschhorn syndrome (WHS) and Patau syndrome are two of the most severe conditions resulting from chromosome abnormalities. WHS is caused by a deletion of 4p16, while Patau syndrome is caused by trisomy for some or all regions of chromosome 13. Though the etiologies of these syndromes differ, they share several features including pre- and postnatal growth retardation, microcephaly, cleft lip and palate, and cardiac anomalies. We present here a female fetus with deletion of 4p16 → pter and duplication of 13q32 → qter due to unbalanced segregation of t(4;13)(p16;q32) in the father. She displayed overlapping features of both of these syndromes on ultrasound. To the best of our knowledge, this is the first report of a fetus with both partial trisomy 13 and deletion of 4p16, the critical region for WHS.

Acute myeloid leukemia associated with hemophagocytic syndrome and t(4;7)(q21;q36)

Hemophagocytic syndrome (HS) is a histiocytic reactive process often associated with infections and/or malignancies. Clonal karyotypic abnormalities have been the hallmark of several hematological malignancies and have been shown to be of clinical significance in terms of both diagnosis and prognosis. While there are limited reports of both clonal and nonclonal abnormalities in HS, their clinical significance has not been established. Detection of such clonal abnormalities, as seen in some cases of HS, may indicate the presence of an occult malignant process, even when there is no microscopic evidence of a hematological malignancy. We report a case of HS in a child with clonal t(4;7)(q21;q36) which later progressed to acute myeloid leukemia (AML) with further clonal evolution. Our case strengthens the argument that cytogenetic studies in HS may be important in identifying the underlying occult malignant process.