Key Spec Table
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|H||FC, ICC, IHC, IH(P), WB||M||Purified||Monoclonal Antibody|
|Presentation||Mouse monoclonal IgG1 in buffer containing 0.02 M Phosphate buffer, 0.25 M NaCl, pH 7.6 with 0.1% sodium azide.|
|Safety Information according to GHS|
|Storage and Shipping Information|
|Storage Conditions||Stable for 1 year at 2-8ºC from date of receipt.|
|Material Size||100 µg|
|Anti-Ki-67, clone Ki-S5||2475762|
|Anti-Ki-67, clone Ki-S5 - 2366564||2366564|
|Anti-Ki-67, clone Ki-S5 - 1951044||1951044|
|Anti-Ki-67, clone Ki-S5 - 1998927||1998927|
|Anti-Ki-67, clone Ki-S5 - 2024193||2024193|
|Anti-Ki-67, clone Ki-S5 - 2055444||2055444|
|Anti-Ki-67, clone Ki-S5 - 2207168||2207168|
|Anti-Ki-67, clone Ki-S5 - 2512440||2512440|
|Anti-Ki-67, clone Ki-S5 - LV1387121||LV1387121|
|Anti-Ki-67, clone Ki-S5 - LV1523210||LV1523210|
|Reference overview||Application||Pub Med ID|
|Biodegradable Gelatin Microcarriers Facilitate Re-Epithelialization of Human Cutaneous Wounds - An In Vitro Study in Human Skin.|
Lönnqvist, S; Rakar, J; Briheim, K; Kratz, G
PloS one 10 e0128093 2015
The possibility to use a suspended tridimensional matrix as scaffolding for re-epithelialization of in vitro cutaneous wounds was investigated with the aid of a human in vitro wound healing model based on viable full thickness skin. Macroporous gelatin microcarriers, CultiSpher-S, were applied to in vitro wounds and cultured for 21 days. Tissue sections showed incorporation of wound edge keratinocytes into the microcarriers and thicker neoepidermis in wounds treated with microcarriers. Thickness of the neoepidermis was measured digitally, using immunohistochemical staining of keratins as epithelial demarcation. Air-lifting of wounds enhanced stratification in control wounds as well as wounds with CultiSpher-S. Immunohistochemical staining revealed expression of keratin 5, keratin 10, and laminin 5 in the neoepidermal component. We conclude that the CultiSpher-S microcarriers can function as tissue guiding scaffold for re-epithelialization of cutaneous wounds.
|Induced pluripotent stem cells reveal functional differences between drugs currently investigated in patients with hutchinson-gilford progeria syndrome.|
Blondel, S; Jaskowiak, AL; Egesipe, AL; Le Corf, A; Navarro, C; Cordette, V; Martinat, C; Laabi, Y; Djabali, K; de Sandre-Giovannoli, A; Levy, N; Peschanski, M; Nissan, X
Stem cells translational medicine 3 510-9 2014
Hutchinson-Gilford progeria syndrome is a rare congenital disease characterized by premature aging in children. Identification of the mutation and related molecular mechanisms has rapidly led to independent clinical trials testing different marketed drugs with a preclinically documented impact on those mechanisms. However, the extensive functional effects of those drugs remain essentially unexplored. We have undertaken a systematic comparative study of the three main treatments currently administered or proposed to progeria-affected children, namely, a farnesyltransferase inhibitor, the combination of an aminobisphosphonate and a statin (zoledronate and pravastatin), and the macrolide antibiotic rapamycin. This work was based on the assumption that mesodermal stem cells, which are derived from Hutchinson-Gilford progeria syndrome-induced pluripotent stem cells expressing major defects associated with the disease, may be instrumental to revealing such effects. Whereas all three treatments significantly improved misshapen cell nuclei typically associated with progeria, differences were observed in terms of functional improvement in prelamin A farnesylation, progerin expression, defective cell proliferation, premature osteogenic differentiation, and ATP production. Finally, we have evaluated the effect of the different drug combinations on this cellular model. This study revealed no additional benefit compared with single-drug treatments, whereas a cytostatic effect equivalent to that of a farnesyltransferase inhibitor alone was systematically observed. Altogether, these results reveal the complexity of the modes of action of different drugs, even when they have been selected on the basis of a similar mechanistic hypothesis, and underscore the use of induced pluripotent stem cell derivatives as a critical and powerful tool for standardized, comparative pharmacological studies.
|Laminin receptor 37/67LR regulates adhesion and proliferation of normal human intestinal epithelial cells.|
Khalfaoui, T; Groulx, JF; Sabra, G; GuezGuez, A; Basora, N; Vermette, P; Beaulieu, JF
PloS one 8 e74337 2013
Interactions between the cell basal membrane domain and the basement membrane are involved in several cell functions including proliferation, migration and differentiation. Intestinal epithelial cells can interact with laminin, a major intestinal basement membrane glycoprotein, via several cell-surface laminin-binding proteins including integrin and non-integrin receptors. The 37/67kDa laminin receptor (37/67LR) is one of these but its role in normal epithelial cells is still unknown. The aim of this study was to characterise the expression pattern and determine the main function of 37/67LR in the normal human small intestinal epithelium. Immunolocalization studies revealed that 37/67LR was predominantly present in the undifferentiated/proliferative region of the human intestinal crypt in both the immature and adult intestine. Using a human intestinal epithelial crypt (HIEC) cell line as experimental model, we determined that 37/67LR was expressed in proliferative cells in both the cytoplasmic and membrane compartments. Small-interfering RNA-mediated reduction of 37/67LR expression led to HIEC cell-cycle reduction and loss of the ability to adhere to laminin-related peptides under conditions not altering ribosomal function. Taken together, these findings indicate that 37/67LR regulates proliferation and adhesion in normal intestinal epithelial cells independently of its known association with ribosomal function.
|MGMT inhibition restores ER? functional sensitivity to antiestrogen therapy.|
Bobustuc, GC; Smith, JS; Maddipatla, S; Jeudy, S; Limaye, A; Isley, B; Caparas, ML; Constantino, SM; Shah, N; Baker, CH; Srivenugopal, KS; Baidas, S; Konduri, SD
Molecular medicine (Cambridge, Mass.) 18 913-29 2012
Antiestrogen therapy resistance remains a huge stumbling block in the treatment of breast cancer. We have found significant elevation of O(6) methylguanine DNA methyl transferase (MGMT) expression in a small sample of consecutive patients who have failed tamoxifen treatment. Here, we show that tamoxifen resistance is accompanied by upregulation of MGMT. Further we show that administration of the MGMT inhibitor, O(6)-benzylguanine (BG), at nontoxic doses, leads to restoration of a favorable estrogen receptor alpha (ER?) phosphorylation phenotype (high p-ER? Ser167/low p-ER? Ser118), which has been reported to correlate with sensitivity to endocrine therapy and improved survival. We also show BG to be a dual inhibitor of MGMT and ER?. In tamoxifen-resistant breast cancer cells, BG alone or in combination with antiestrogen (tamoxifen [TAM]/ICI 182,780 [fulvestrant, Faslodex]) therapy enhances p53 upregulated modulator of apoptosis (PUMA) expression, cytochrome C release and poly (ADP-ribose) polymerase (PARP) cleavage, all indicative of apoptosis. In addition, BG increases the expression of p21(cip1/waf1). We also show that BG, alone or in combination therapy, curtails the growth of tamoxifen-resistant breast cancer in vitro and in vivo. In tamoxifen-resistant MCF7 breast cancer xenografts, BG alone or in combination treatment causes significant delay in tumor growth. Immunohistochemistry confirms that BG increases p21(cip1/waf1) and p-ER? Ser167 expression and inhibits MGMT, ER?, p-ER? Ser118 and ki-67 expression. Collectively, our results suggest that MGMT inhibition leads to growth inhibition of tamoxifen-resistant breast cancer in vitro and in vivo and resensitizes tamoxifen-resistant breast cancer cells to antiestrogen therapy. These findings suggest that MGMT inhibition may provide a novel therapeutic strategy for overcoming antiestrogen resistance.
|Progenitor-like traits contribute to patient survival and prognosis in oligodendroglial tumors.|
Ng, FS; Toh, TB; Ting, EH; Koh, GR; Sandanaraj, E; Phong, M; Wong, SS; Leong, SH; Kon, OL; Tucker-Kellogg, G; Ng, WH; Ng, I; Tang, C; Ang, BT
Clinical cancer research : an official journal of the American Association for Cancer Research 18 4122-35 2012
Patient-derived glioma-propagating cells (GPC) contain karyotypic and gene expression profiles that are found in the primary tumor. However, their clinical relevance is unclear. We ask whether GPCs contribute to disease progression and survival outcome in patients with glioma by analyzing gene expression profiles.We tapped into public sources of GPC gene expression data and derived a gene signature distinguishing oligodendroglial from glioblastoma multiforme (GBM) GPCs. By adapting a method in glioma biology, the Connectivity Map, we interrogated its strength of association in public clinical databases. We validated the top-ranking signaling pathways Wnt, Notch, and TGF?, in GPCs and primary tumor specimens.We observed that patients with better prognosis correlated with oligodendroglial GPC features and lower tumor grade, and this was independent of the current clinical indicator, 1p/19q status. Patients with better prognosis had proneural tumors whereas the poorly surviving cohort had mesenchymal tumors. In addition, oligodendroglial GPCs were more sensitive to Wnt and Notch inhibition whereas GBM GPCs responded to TGF?R1 inhibition.We provide evidence that GPCs are clinically relevant. In addition, the more favorable prognosis of oligodendroglial tumors over GBM could be recapitulated transcriptomically at the GPC level, underscoring the relevance of this cellular model. Our gene signature detects molecular heterogeneity in oligodendroglial tumors that cannot be accounted for by the 1p/19q status alone, indicating that stem-like traits contribute to clinical status. Collectively, these data highlight the limitation of morphology-based histologic analyses in tumor classification, consequently impacting on treatment decisions.
|Identification of a Src tyrosine kinase/SIAH2 E3 ubiquitin ligase pathway that regulates C/EBP? expression and contributes to transformation of breast tumor cells.|
Sarkar, TR; Sharan, S; Wang, J; Pawar, SA; Cantwell, CA; Johnson, PF; Morrison, DK; Wang, JM; Sterneck, E
Molecular and cellular biology 32 320-32 2012
The transcription factor CCAAT/enhancer-binding protein delta (C/EBP?, CEBPD) is a tumor suppressor that is downregulated during breast cancer progression but may also promote metastasis. Here, we have investigated the mechanism(s) regulating C/EBP? expression and its role in human breast cancer cells. We describe a novel pathway by which the tyrosine kinase Src downregulates C/EBP? through the SIAH2 E3 ubiquitin ligase. Src phosphorylates SIAH2 in vitro and leads to tyrosine phosphorylation and activation of SIAH2 in breast tumor cell lines. SIAH2 interacts with C/EBP?, but not C/EBP?, and promotes its polyubiquitination and proteasomal degradation. Src/SIAH2-mediated inhibition of C/EBP? expression supports elevated cyclin D1 levels, phosphorylation of retinoblastoma protein (Rb), motility, invasive properties, and survival of transformed cells. Pharmacological inhibition of Src family kinases by SKI-606 (bosutinib) induces C/EBP? expression in an SIAH2-dependent manner, which is necessary for "therapeutic" responses to SKI-606 in vitro. Ectopic expression of degradation-resistant mutants of C/EBP?, which do not interact with SIAH2 and/or cannot be polyubiquitinated, prevents full transformation of MCF-10A cells by activated Src (Src truncated at amino acid 531 [Src-531]) in vitro. These data reveal that C/EBP? expression can be regulated at the protein level by oncogenic Src kinase signals through SIAH2, thus contributing to breast epithelial cell transformation.
|3-phosphoinositide-dependent kinase 1 controls breast tumor growth in a kinase-dependent but akt-independent manner.|
Paolo Armando Gagliardi,Laura di Blasio,Francesca Orso,Giorgio Seano,Roberto Sessa,Daniela Taverna,Federico Bussolino,Luca Primo
Neoplasia (New York, N.Y.) 14 2012
3-Phosphoinositide-dependent protein kinase 1 (PDK1) is the pivotal element of the phosphatidylinositol 3 kinase (PI3K) signaling pathway because it phosphorylates Akt/PKB through interactions with phosphatidylinositol 3,4,5 phosphate. Recent data indicate that PDK1 is overexpressed in many breast carcinomas and that alterations of PDK1 are critical in the context of oncogenic PI3K activation. However, the role of PDK1 in tumor progression is still controversial. Here, we show that PDK1 is required for anchorage-independent and xenograft growth of breast cancer cells harboring either PI3KCA or KRAS mutations. In fact, PDK1 silencing leads to increased anoikis, reduced soft agar growth, and pronounced apoptosis inside tumors. Interestingly, these phenotypes are reverted by PDK1 wild-type but not kinase-dead mutant, suggesting a relevant role of PDK1 kinase activity, even if PDK1 is not relevant for Akt activation here. Indeed, the expression of constitutively active forms of Akt in PDK1 knockdown cells is unable to rescue the anchorage-independent growth. In addition, Akt down-regulation and pharmacological inhibition do not inhibit the effects of PDK1 overexpression. In summary, these results suggest that PDK1 may contribute to breast cancer, even in the absence of PI3K oncogenic mutations and through both Akt-dependent and Akt-independent mechanisms.
|Reduction of ?-amyloid deposits by ?-secretase inhibitor is associated with the attenuation of secondary damage in the ipsilateral thalamus and sensory functional improvement after focal cortical infarction in hypertensive rats.|
Zhang, Y; Xing, S; Zhang, J; Li, J; Li, C; Pei, Z; Zeng, J
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 31 572-9 2011
Abnormal ?-amyloid (A?) deposits in the thalamus have been reported after cerebral cortical infarction. In this study, we investigated the association of A? deposits, with the secondary thalamic damage after focal cortical infarction in rats. Thirty-six stroke-prone renovascular hypertensive rats were subjected to distal middle cerebral artery occlusion (MCAO) and then randomly divided into MCAO, vehicle, and N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT) groups and 12 sham-operated rats as control. The DAPT was administered orally at 72?hours after MCAO. Seven days after MCAO, sensory function, neuron loss, and glial activation and proliferation were evaluated using adhesive removal test, Nissl staining, and immunostaining, respectively. Thalamic A? accumulation was evaluated using immunostaining and enzyme-linked immunosorbent assay (ELISA). Compared with vehicle group, the ipsilateral thalamic A?, neuronal loss, glial activation and proliferation, and the mean time to remove the stimulus from right forepaw significantly decreased in DAPT group. The mean time to remove the stimulus from the right forepaw and thalamic A? burden were both negatively correlated with the number of thalamic neurons. These findings suggest that A? deposits are associated with the secondary thalamic damage. Reduction of thalamic A? by ?-secretase inhibitor may attenuate the secondary damage and improve sensory function after cerebral cortical infarction.
|XB130, a novel adaptor protein, promotes thyroid tumor growth.|
Shiozaki, Atsushi, et al.
Am. J. Pathol., 178: 391-401 (2011) 2011
Adaptor proteins with multimodular structures can participate in the regulation of various cellular functions. We have cloned a novel adaptor protein, XB130, which binds the p85? subunit of phosphatidyl inositol 3-kinase and subsequently mediates signaling through RET/PTC in TPC-1 thyroid cancer cells. In the present study, we sought to determine the role of XB130 in the tumorigenesis in vivo and in related molecular mechanisms. In WRO thyroid cancer cells, knockdown of XB130 using small interfering RNA inhibited G(1)-S phase progression, induced spontaneous apoptosis, and enhanced intrinsic and extrinsic apoptotic stimulus-induced cell death. Growth of tumors in nude mice formed from XB130 shRNA stably transfected WRO cells were significantly reduced, with decreased cell proliferation and increased apoptosis. Microarray analysis identified 246 genes significantly changed in XB130 shRNA transfected cells. Among them, 57 genes are related to cell proliferation or survival, including many transcription regulators. Ingenuity Pathway Analysis showed that the top-ranked disease related to XB130 is cancer, and the top molecular and cellular functions are cellular growth and proliferation and cell cycle. A human thyroid tissue microarray study identified expression of XB130 in normal thyroid tissue as well as in human thyroid carcinomas. These observations suggest that the expression of XB130 in these cancer cells may affect cell proliferation and survival by controlling the expression of multiple genes, especially transcription regulators.
|Blockade of MGMT expression by O6 benzyl guanine leads to inhibition of pancreatic cancer growth and induction of apoptosis.|
Konduri SD, Ticku J, Bobustuc GC, Sutphin RM, Colon J, Isley B, Bhakat KK, Srivenugopal KS, Baker CH
Clinical cancer research : an official journal of the American Association for Cancer Research 15 6087-95 2009
PURPOSE: We sought to determine whether administration of a MGMT blocker, O(6)-benzyl guanine (O(6)BG), at an optimal biological dose alone or in combination with gemcitabine inhibits human pancreatic cancer cell growth. EXPERIMENTAL DESIGN: Human pancreatic cancer L3.6pl and PANC1 cells were treated with O(6)BG, either alone or in combination with gemcitabine, and the therapeutic efficacy and biological activity of these drug combinations were investigated. RESULTS: O(6)BG sensitized pancreatic cancer cells to gemcitabine. Protein and mRNA expression of MGMT, cyclin B1, cyclin B2, cyclin A, and ki-67 were significantly decreased in the presence of O(6)BG. In sharp contrast, protein expression and mRNA message of p21(cip1) were significantly increased. Interestingly, O(6)BG increases p53-mediated p21(cip1) transcriptional activity and suppresses cyclin B1. In addition, our results indicate that p53 is recruited to p21 promoter. Furthermore, an increase in p21(cip1) and a decrease in cyclin transcription are p53 dependent. The volume of pancreatic tumors was reduced by 27% in mice treated with gemcitabine alone, by 47% in those treated with O(6)BG alone, and by 65% in those mice given combination. Immunohistochemical analysis showed that O(6)BG inhibited expression of MGMT and cyclins, and increased expression of p21(cip1). Furthermore, there was a significant decrease in tumor cell proliferation and an increase in tumor cell apoptosis. CONCLUSIONS: Collectively, our results show that decreased MGMT expression is correlated with p53 activation, and significantly reduced primary pancreatic tumor growth. These findings suggest that O(6)BG either alone or in combination with gemcitabine may provide a novel and effective approach for the treatment of human pancreatic cancer.
|Anti-Ki-67, clone Ki-S5 - Data Sheet|
|Reprogramming Cell Fate and Function Novel Strategies for iPSC Generation, Characterization, and Differentiation|