bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Pseudopodial Actin Dynamics Control Epithelial-Mesenchymal Transition in Metastatic Cancer Cells
Authors: Shankar Jay , Messenberg Anat , Chan Jackie , Underhill T. Michael , Foster Leonard J. , Nabi Ivan R.
Published: March 2024

Abstract
A key cellular process associated with the invasive or metastatic program in many cancers is the transformation of epithelial cells toward a mesenchymal state, a process called epithelial to mesenchymal transition or EMT. Actin-dependent protrusion of cell pseudopodia is a critical element of mesenchymal cell migration and therefore of cancer metastasis. However, whether EMT occurs in human cancers and, in particular, whether it is a prerequisite for tumor cell invasion and metastasis, remains a subject of debate. Microarray and proteomic analysis of actin-rich pseudopodia from six metastatic human tumor cell lines identified 384 mRNAs and 64 proteins common to the pseudopodia of six metastatic human tumor cell lines of various cancer origins leading to the characterization of 19 common pseudopod-specific proteins. Four of these (AHNAK, septin-9, eIF4E, and S100A11) are shown to be essential for pseudopod protrusion and tumor cell migration and invasion. Knockdown of each of these proteins in metastatic cells resulted in reduced actin cytoskeleton dynamics and induction of mesenchymal-epithelial transition (MET) that could be prevented by the stabilization of the actin cytoskeleton. Actin-dependent pseudopodial protrusion and tumor cell migration are therefore determinants of EMT. Protein regulators of pseudopodial actin dynamics may represent unique molecular targets to induce MET and thereby inhibit the metastatic potential of tumor cells. Cancer Res; 70(9); 3780–90. ©2010 AACR.
Data from The Bioreductive Prodrug PR-104A Is Activated under Aerobic Conditions by Human Aldo-Keto Reductase 1C3
Authors: Guise Christopher P. , Abbattista Maria R. , Singleton Rachelle S. , Holford Samuel D. , Connolly Joanna , Dachs Gabi U. , Fox Stephen B. , Pollock Robert , Harvey Justin , Guilford Parry , Doñate Fernando , Wilson William R. , Patterson Adam V.
Published: March 2024

Abstract
PR-104, currently in phase II clinical trials, is a phosphate ester pre-prodrug which is converted in vivo to its cognate alcohol, PR-104A, a prodrug designed to exploit tumor hypoxia. Bioactivation occurs via one-electron reduction to DNA crosslinking metabolites in the absence of oxygen. However, certain tumor cell lines activate PR-104A in the presence of oxygen, suggesting the existence of an aerobic nitroreductase. Microarray analysis identified a cluster of five aldo-keto reductase (AKR) family members whose expressions correlated with aerobic metabolism of PR-104A. Plasmid-based expression of candidate genes identified aldo-keto reductase 1C3 as a novel nitroreductase. AKR1C3 protein was detected by Western blot in 7 of 23 cell lines and correlated with oxic PR-104A metabolism, an activity which could be partially suppressed by Nrf2 RNAi knockdown (or induced by Keap1 RNAi), indicating regulation by the ARE pathway. AKR1C3 was unable to sensitize cells to 10 other bioreductive prodrugs and was associated with single-agent PR-104 activity across a panel of 9 human tumor xenograft models. Overexpression in two AKR1C3-negative tumor xenograft models strongly enhanced PR-104 antitumor activity. A population level survey of AKR1C3 expression in 2,490 individual cases across 19 cancer types using tissue microarrays revealed marked upregulation of AKR1C3 in a subset including hepatocellular, bladder, renal, gastric, and non–small cell lung carcinoma. A survey of normal tissue AKR1C3 expression suggests the potential for tumor-selective PR-104A activation by this mechanism. These findings have significant implications for the clinical development of PR-104. Cancer Res; 70(4); 1573–84
Data from Prospective Study of the Association of Serum γ-Glutamyltransferase with Cervical Intraepithelial Neoplasia III and Invasive Cervical Cancer
Authors: Strasak Alexander M. , Goebel Georg , Concin Hans , Pfeiffer Ruth M. , Brant Larry J. , Nagel Gabriele , Oberaigner Willi , Concin Nicole , Diem Günter , Ruttmann Elfriede , Gruber-Moesenbacher Ulrike , Offner Felix , Pompella Alfonso , Pfeiffer Karl P. , Ulmer Hanno
Published: March 2024

Abstract
Epidemiologic studies indicate that elevated levels of γ-glutamyltransferase (GGT), a key enzyme of glutathione metabolism, might be associated with increased cancer risk. Furthermore, preclinical studies support a role for GGT in tumor invasion and progression. However, the relationship between GGT and risks of cervical intraepithelial neoplasia III (CIN-III) and invasive cervical cancer (ICC) have not been evaluated. We investigated the association of enzymatically determined GGT in blood serum with subsequent incidence of CIN-III and ICC in a prospective population-based cohort of 92,843 women ages 18 to 95, of whom 79% had at least one gynecologic examination including Pap smear testing during follow-up. Cox regression was used to compute adjusted hazard ratios (HR) with 95% confidence intervals for the association of GGT with CIN-III and ICC. During median follow-up of 13.8 years, 702 CIN-III and 117 ICC diagnoses were observed. Compared with normal low GGT (<17.99 units/L), risk of ICC was significantly elevated for all other baseline GGT categories, with adjusted HRs of 2.31 (1.49–3.59) for normal high GGT (18.00–35.99 units/L), 2.76 (1.52–5.02) for elevated GGT (36.00–71.99 units/L), and 3.38 (1.63–7.00) for highly elevated GGT [>72.00 units/L; P trend < 0.0001, HR log unit increase 3.45 (1.92–6.19)]. In contrast, associations between GGT serum levels and CIN-III risk were not statistically significant in the main analysis. Exclusion of the first 2 or 5 years of follow-up did not change the results. Effects did not differ by age, body mass index, or socioeconomic status. Our findings implicate GGT in the progression of premalignant cervical lesions to invasive cancer. Cancer Res; 70(9); 3586–93. ©2010 AACR.
Data from miR-212 Increases Tumor Necrosis Factor–Related Apoptosis-Inducing Ligand Sensitivity in Non–Small Cell Lung Cancer by Targeting the Antiapoptotic Protein PED
Authors: Incoronato Mariarosaria , Garofalo Michela , Urso Loredana , Romano Giulia , Quintavalle Cristina , Zanca Ciro , Iaboni Margherita , Nuovo Gerald , Croce Carlo Maria , Condorelli Gerolama
Published: March 2024

Abstract
PED/PEA-15 (PED) is a death effector domain family member of 15 kDa with a broad antiapoptotic function found overexpressed in a number of different human tumors, including lung cancer. To date, the mechanisms that regulate PED expression are unknown. Therefore, we address this point by the identification of microRNAs that in non–small cell lung cancer (NSCLC) modulate PED levels. In this work, we identify miR-212 as a negative regulator of PED expression. We also show that ectopic expression of this miR increases tumor necrosis factor–related apoptosis-inducing ligand (TRAIL)–induced cell death in NSCLC cells. In contrast, inhibition of endogenous miR-212 by use of antago-miR results in increase of PED protein expression and resistance to TRAIL treatment. Besides, in NSCLC, we show both in vitro and in vivo that PED and miR-212 expressions are inversely correlated, that is, PED is upregulated and miR-212 is rarely expressed. In conclusion, these findings suggest that miR-212 should be considered as a tumor suppressor because it negatively regulates the antiapoptotic protein PED and regulates TRAIL sensitivity. Cancer Res; 70(9); 3638–46. ©2010 AACR.
Data from Anti–Vascular Endothelial Growth Factor Therapies as a Novel Therapeutic Approach to Treating Neurofibromatosis-Related Tumors
Authors: Wong Hon Kit , Lahdenranta Johanna , Kamoun Walid S. , Chan Annie W. , McClatchey Andrea I. , Plotkin Scott R. , Jain Rakesh K. , di Tomaso Emmanuelle
Published: March 2024

Abstract
Patients with bilateral vestibular schwannomas associated with neurofibromatosis type 2 (NF2) experience significant morbidity such as complete hearing loss. We have recently shown that treatment with bevacizumab provided tumor stabilization and hearing recovery in a subset of NF2 patients with progressive disease. In the current study, we used two animal models to identify the mechanism of action of anti–vascular endothelial growth factor (VEGF) therapy in schwannomas. The human HEI193 and murine Nf2−/− cell lines were implanted between the pia and arachnoid meninges as well as in the sciatic nerve to mimic central and peripheral schwannomas. Mice were treated with bevacizumab (10 mg/kg/wk i.v.) or vandetanib (50 mg/kg/d orally) to block the VEGF pathway. Using intravital and confocal microscopy, together with whole-body imaging, we measured tumor growth delay, survival rate, as well as blood vessel structure and function at regular intervals. In both models, tumor vessel diameter, length/surface area density, and permeability were significantly reduced after treatment. After 2 weeks of treatment, necrosis in HEI193 tumors and apoptosis in Nf2−/− tumors were significantly increased, and the tumor growth rate decreased by an average of 50%. The survival of mice bearing intracranial schwannomas was extended by at least 50%. This study shows that anti-VEGF therapy normalizes the vasculature of schwannoma xenografts in nude mice and successfully controls the tumor growth, probably by reestablishing a natural balance between VEGF and semaphorin 3 signaling. Cancer Res; 70(9); 3483–93. ©2010 AACR.
Data from Protection from Rapamycin-Induced Apoptosis by Insulin-Like Growth Factor-I Is Partially Dependent on Protein Kinase C Signaling
Authors: Thimmaiah Kuntebommanahalli N. , Easton John B. , Houghton Peter J.
Published: March 2024

Abstract
Rapamycin-induced apoptosis in sarcoma cells is inhibited by insulin-like growth factor-I (IGF-I) through a signaling pathway independent of Ras-extracellular signal-regulated kinase 1/2 and Akt. IGF-I induces Bad phosphorylation (Ser112, Ser136, and Ser155) in a pathway involving phosphoinositide 3′ kinase (PI3K) and protein kinase C (PKC; μ, ϵ, or θ) resulting in sequestering Bad from mitochondria and subsequently interacting with 14-3-3γ in the cytosol. Gene knockdown of Bad, Bid, Akt1, Akt2, PKC-μ, PKC-ϵ, or PKC-θ was achieved by transient transfection using small interfering RNAs. Results indicate that IGF-I signaling to Bad requires activation of PI3K and PKC (μ, θ, ϵ) but not mTOR, Ras-extracellular signal-regulated kinase 1/2, protein kinase A, or p90RSK. Wortmannin blocked the phosphorylation of PKC-μ (Ser744/Ser748), suggesting that PI3K is required for the activation of PKCs. PKCs phosphorylate Bad under in vitro conditions, and the association of phosphorylated Bad with PKC-μ or PKC-ϵ, as shown by immunoprecipitation, indicated direct involvement of PKCs in Bad phosphorylation. To confirm these results, cells overexpressing pEGFP-N1, wt-Bad, or Bad with a single site mutated (Ser112Ala; Ser136Ala; Ser155Ala), two sites mutated (Ser112/136Ala; Ser112/155Ala; Ser136/155Ala), or the triple mutant were tested. IGF-I protected completely against rapamycin-induced apoptosis in cells overexpressing wt-Bad and mutants having either one or two sites of phosphorylation mutated. Knockdown of Bid using small interfering RNA showed that Bid is not required for rapamycin-induced cell death. Collectively, these data suggest that IGF-I–induced phosphorylation of Bad at multiple sites via a pathway involving PI3K and PKCs is important for protecting sarcoma cells from rapamycin-induced apoptosis. Cancer Res; 70(5); 2000–9
Data from ID1 Enhances Docetaxel Cytotoxicity in Prostate Cancer Cells through Inhibition of p21
Authors: Geng Hao , Rademacher Brooks L. , Pittsenbarger Janet , Huang Chung-Ying , Harvey Christopher T. , Lafortune Marie C. , Myrthue Anne , Garzotto Mark , Nelson Peter S. , Beer Tomasz M. , Qian David Z.
Published: March 2024

Abstract
To identify potential mechanisms underlying prostate cancer chemotherapy response and resistance, we compared the gene expression profiles in high-risk human prostate cancer specimens before and after neoadjuvant chemotherapy and radical prostatectomy. Among the molecular signatures associated with chemotherapy, transcripts encoding inhibitor of DNA binding 1 (ID1) were significantly upregulated. The patient biochemical relapse status was monitored in a long-term follow-up. Patients with ID1 upregulation were found to be associated with longer relapse-free survival than patients without ID1 increase. This in vivo clinical association was mechanistically investigated. The chemotherapy-induced ID1 upregulation was recapitulated in the prostate cancer cell line LNCaP. Docetaxel dose-dependently induced ID1 transcription, which was mediated by ID1 promoter E-box chromatin modification and c-Myc binding. Stable ID1 overexpression in LNCaP increased cell proliferation, promoted G1 cell cycle progression, and enhanced docetaxel-induced cytotoxicity. These changes were accompanied by a decrease in cellular mitochondria content, an increase in BCL2 phosphorylation at serine 70, caspase-3 activation, and poly(ADP-ribose) polymerase cleavage. In contrast, ID1 siRNA in the LNCaP and C42B cell lines reduced cell proliferation and decreased docetaxel-induced cytotoxicity by inhibiting cell death. ID1-mediated chemosensitivity enhancement was in part due to ID1 suppression of p21. Overexpression of p21 in LNCaP-ID1–overexpressing cells restored the p21 level and reversed ID1-enhanced chemosensitivity. These molecular data provide a mechanistic rationale for the observed in vivo clinical association between ID1 upregulation and relapse-free survival. Taken together, it shows that ID1 expression has a novel therapeutic role in prostate cancer chemotherapy and prognosis. Cancer Res; 70(8); 3239–48. ©2010 AACR.
Data from An Oncogenic Role for ETV1 in Melanoma
Authors: Jané-Valbuena Judit , Widlund Hans R. , Perner Sven , Johnson Laura A. , Dibner Aurora C. , Lin William M. , Baker Alissa C. , Nazarian Rosalynn M. , Vijayendran Krishna G. , Sellers William R. , Hahn William C. , Duncan Lyn M. , Rubin Mark A. , Fisher David E. , Garraway Levi A.
Published: March 2024

Abstract
Copy gains involving chromosome 7p represent one of the most common genomic alterations found in melanomas, suggesting the presence of “driver” cancer genes. We identified several tumor samples that harbored focal amplifications situated at the peak of common chromosome 7p gains, in which the minimal common overlapping region spanned the ETV1 oncogene. Fluorescence in situ hybridization analysis revealed copy gains spanning the ETV1 locus in >40% of cases, with ETV1 amplification (>6 copies/cell) present in 13% of primary and 18% of metastatic melanomas. Melanoma cell lines, including those with ETV1 amplification, exhibited dependency on ETV1 expression for proliferation and anchorage-independent growth. Moreover, overexpression of ETV1 in combination with oncogenic NRASG12D transformed primary melanocytes and promoted tumor formation in mice. ETV1 overexpression elevated microphthalmia-associated transcription factor expression in immortalized melanocytes, which was necessary for ETV1-dependent oncogenicity. These observations implicate deregulated ETV1 in melanoma genesis and suggest a pivotal lineage dependency mediated by oncogenic ETS transcription factors in this malignancy. Cancer Res; 70(5); 2075–84
Data from Antibodies to Merkel Cell Polyomavirus T Antigen Oncoproteins Reflect Tumor Burden in Merkel Cell Carcinoma Patients
Authors: Paulson Kelly G. , Carter Joseph J. , Johnson Lisa G. , Cahill Kevin W. , Iyer Jayasri G. , Schrama David , Becker Juergen C. , Madeleine Margaret M. , Nghiem Paul , Galloway Denise A.
Published: March 2024

Abstract
Merkel cell polyomavirus (MCPyV) is a common infectious agent that is likely involved in the etiology of most Merkel cell carcinomas (MCC). Serum antibodies recognizing the MCPyV capsid protein VP1 are detectable at high titer in nearly all MCC patients and remain stable over time. Although antibodies to the viral capsid indicate prior MCPyV infection, they provide limited clinical insight into MCC because they are also detected in more than half of the general population. We investigated whether antibodies recognizing MCPyV large and small tumor-associated antigens (T-Ag) would be more specifically associated with MCC. Among 530 population control subjects, these antibodies were present in only 0.9% and were of low titer. In contrast, among 205 MCC cases, 40.5% had serum IgG antibodies that recognize a portion of T-Ag shared between small and large T-Ags. Among cases, titers of T-Ag antibodies fell rapidly (∼8-fold per year) in patients whose cancer did not recur, whereas they rose rapidly in those with progressive disease. Importantly, in several patients who developed metastases, the rise in T-Ag titer preceded clinical detection of disease spread. These results suggest that antibodies recognizing T-Ag are relatively specifically associated with MCC, do not effectively protect against disease progression, and may serve as a clinically useful indicator of disease status. Cancer Res; 70(21); 8388–97. ©2010 AACR.
Data from Molecular Target Class Is Predictive of In vitro Response Profile
Authors: Greshock Joel , Bachman Kurtis E. , Degenhardt Yan Y. , Jing Junping , Wen Yuan H. , Eastman Stephen , McNeil Elizabeth , Moy Christopher , Wegrzyn Ronald , Auger Kurt , Hardwicke Mary Ann , Wooster Richard
Published: March 2024

Abstract
Preclinical cellular response profiling of tumor models has become a cornerstone in the development of novel cancer therapeutics. As efforts to predict clinical efficacy using cohorts of in vitro tumor models have been successful, expansive panels of tumor-derived cell lines can recapitulate an “all comers” efficacy trial, thereby identifying which tumors are most likely to benefit from treatment. The response profile of a therapy is most often studied in isolation; however, drug treatment effect patterns in tumor models across a diverse panel of compounds can help determine the value of unique molecular target classes in specific tumor cohorts. To this end, a panel of 19 compounds was evaluated against a diverse group of cancer cell lines (n = 311). The primary oncogenic targets were a key determinant of concentration-dependent proliferation response, as a total of five of six, four of four, and five of five phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway, insulin-like growth factor-I receptor (IGF-IR), and mitotic inhibitors, respectively, clustered with others of that common target class. In addition, molecular target class was correlated with increased responsiveness in certain histologies. A cohort of PI3K/AKT/mTOR inhibitors was more efficacious in breast cancers compared with other tumor types, whereas IGF-IR inhibitors more selectively inhibited growth in colon cancer lines. Finally, specific phenotypes play an important role in cellular response profiles. For example, luminal breast cancer cells (nine of nine; 100%) segregated from basal cells (six of seven; 86%). The convergence of a common cellular response profile for different molecules targeting the same oncogenic pathway substantiates a rational clinical path for patient populations most likely to benefit from treatment. Cancer Res; 70(9); 3677–86. ©2010 AACR.
Data from BRCA1-IRIS Overexpression Promotes Cisplatin Resistance in Ovarian Cancer Cells
Authors: Chock Kerri L. , Allison Jamie M.S. , Shimizu Yoshiko , ElShamy Wael M.
Published: March 2024

Abstract
Evasion of apoptosis plays a key role in cancer development, drug resistance, and recurrence. The BRCA1 locus product protein BRCA1-IRIS is overexpressed in several cisplatin-resistant ovarian cancer cell lines, but its relationship to resistance is uncertain. Here, we show that in human ovarian surface epithelial (HOSE) cells, overexpression of BRCA1-IRIS triggers expression of the antiapoptotic protein survivin. Negative modulation of phosphatidylinositol 3-kinase (PI3K) signaling or AKT silencing reduced survivin expression in this setting. Conversely, silencing BRCA1-IRIS in ovarian cancer cell lines derepressed PTEN expression along with the antiapoptotic AKT targets FOXO1 and FOXO3a, suppressing survivin expression. Cisplatin (≤50 μmol/L) exposure was sufficient to activate expression of the BRCA1-IRIS-AKT-survivin cascade in HOSE cells, whereas under similar conditions cisplatin failed to induce apoptosis in ovarian cancer cell lines expressing this regulatory cascade. Mechanistic investigations indicated that BRCA1-IRIS triggers survivin expression through a PI3K/AKT-dependent pathway involving NF-κB, but also through a PI3K/AKT-independent pathway involving PTEN, FOXO1, and FOXO3a. Our findings indicate how BRCA1-IRIS overexpression prevents chemotherapy-induced cell death by upregulating expression of survivin, and they highlight this regulatory cascade as a candidate focus to improve treatment of advanced drug-resistant ovarian cancers. Cancer Res; 70(21); 8782–91. ©2010 AACR.
Data from Heat Shock Protein 27 Differentiates Tolerogenic Macrophages That May Support Human Breast Cancer Progression
Authors: Banerjee Sanjib , Lin Chuen-Fu L. , Skinner Kristin A. , Schiffhauer Linda M. , Peacock James , Hicks David G. , Redmond Eileen M. , Morrow David , Huston Alissa , Shayne Michelle , Langstein Howard N. , Miller-Graziano Carol L. , Strickland Jennifer , O'Donoghue Lauren , De Asit K.
Published: March 2024

Abstract
Tumor cells release several factors that can help the progression of the tumor by directly supporting tumor growth and/or suppressing host antitumor immunity. Here, we report that human primary breast tumor cells not only express elevated levels of heat shock protein 27 (Hsp27) at the intracellular level but also release extremely high levels of Hsp27 compared with the same patients' serum Hsp27 levels, predicting an acutely increased concentration of soluble Hsp27 in the human breast tumor microenvironment (HBTM). We demonstrate that Hsp27 levels in the HBTM can be extremely elevated as evidenced by high soluble Hsp27 levels in patients' tumor interstitial fluid. Because increasing numbers of tumor-associated macrophages (TAM) in the HBTM negatively correlate to patients' clinical outcomes and we have previously reported the immunoregulatory activity of soluble Hsp27, here, we tested for any specific effects of soluble Hsp27 on human monocyte to macrophage differentiation. We demonstrate that soluble Hsp27 causes the differentiation of monocytes to macrophages with immuno-tolerizing phenotypes (HLA-DRlow, CD86low, PD-L1high, ILT2high, and ILT4high). We detected the presence of TAMs with similar phenotypes in breast cancer patients. Hsp27-differentiated macrophages induce severe unresponsiveness/anergy in T cells. Moreover, these macrophages lose tumoricidal activity but become extremely proangiogenic, inducing significant neovascularization, a process that is critically important for tumor growth. Thus, our data demonstrate a novel immune escape and tumor growth–supporting mechanism mediated by soluble Hsp27 that may be operative in human breast cancer. Cancer Res; 71(2); 318–27. ©2011 AACR.
Data from Piracy of Prostaglandin E2/EP Receptor–Mediated Signaling by Kaposi's Sarcoma-Associated Herpes Virus (HHV-8) for Latency Gene Expression: Strategy of a Successful Pathogen
Authors: George Paul Arun , Sharma-Walia Neelam , Kerur Nagaraj , White Carl , Chandran Bala
Published: March 2024

Abstract
Kaposi's sarcoma-associated herpes virus (KSHV) is implicated in the pathogenesis of KS, a chronic inflammation-associated malignancy. Cyclooxygenase-2 (COX-2) and its metabolite prostaglandin E2 (PGE2), two pivotal proinflammatory/oncogeneic molecules, are proposed to play roles in the expression of major KSHV latency-associated nuclear antigen-1 (LANA-1). Microsomal PGE2 synthase, PGE2, and its receptors (EP1, EP2, EP3, and EP4) were detected in KS lesions with the distinct staining of EP2/EP4 in KS lesions. In latently infected endothelial TIVE-LTC cells, EP receptor antagonists downregulated LANA-1 expression as well as Ca2+, p-Src, p-PI3K, p-PKCζ/λ, and p-NF-κB, which are also some of the signal molecules proposed to be important in KS pathogenesis. Exogenous PGE2 and EP receptor agonists induced the LANA-1 promoter in 293 cells, and YY1, Sp1, Oct-1, Oct-6, C/EBP, and c-Jun transcription factors seem to be involved in this induction. PGE2/EP receptor-induced LANA-1 promoter activity was downregulated significantly by the inhibition of Ca2+, p-Src, p-PI3K, p-PKCζ/λ, and p-NF-κB. These findings implicate the inflammatory PGE2/EP receptors and the associated signal molecules in herpes virus latency and uncover a novel paradigm that shows the evolution of KSHV genome plasticity to use inflammatory response for its survival advantage of maintaining latent gene expression. These data also suggest that potential use of anti-COX-2 and anti-EP receptor therapy may not only ameliorate the chronic inflammation associated with KS but could also lead to elimination of the KSHV latent infection and the associated KS lesions. Cancer Res; 70(9); 3697–3708. ©2010 AACR.
Data from Pierce1, a Novel p53 Target Gene Contributing to the Ultraviolet-Induced DNA Damage Response
Authors: Sung Young Hoon , Kim Hye Jin , Devkota Sushil , Roh Jusik , Lee Jaehoon , Rhee Kunsoo , Bahk Young Yil , Lee Han-Woong
Published: March 2024

Abstract
Retinoblastoma (Rb) and p53 genes are mutated or inactivated in most human cancers and mutually regulate each other. Recently, we reported that expression of diverse genes was altered in Rb-deficient mouse embryonic fibroblasts (MEF). In this study, we found that Pierce1, a novel transcript upregulated in Rb-deficient MEFs, is a transcriptional target of p53. Although Pierce1 promoter did not respond to the ectopic expression of E2F1, it was strongly activated by p53 via 2 cis-elements. Consistently, the expression of Pierce1 was induced by genotoxic stresses that activate p53 but was not detected in p53-deficient MEFs. Pierce1 was posttranslationally stabilized by ultraviolet C (UVC) irradiation, and UVC-activated ATR (ataxia telangiectasia-mutated and Rad3-related) signaling suppressed proteosomal degradation of Pierce1 protein. Furthermore, knockdown of Pierce1 compromised the checkpoint response of wild-type MEFs to UVC irradiation, accompanying the diminished expression of p53 target genes. Together, our data suggest that Pierce1 is an important p53 target gene contributing to normal DNA damage response and may play crucial roles in maintaining genomic integrity against genotoxic stresses, including UVC irradiation. Cancer Res; 70(24); 10454–63. ©2010 AACR.
Data from Class III β-Tubulin Expression Predicts Prostate Tumor Aggressiveness and Patient Response to Docetaxel-Based Chemotherapy
Authors: Ploussard Guillaume , Terry Stéphane , Maillé Pascale , Allory Yves , Sirab Nanor , Kheuang Laurence , Soyeux Pascale , Nicolaiew Nathalie , Coppolani Estelle , Paule Bernard , Salomon Laurent , Culine Stéphane , Buttyan Ralph , Vacherot Francis , de la Taille Alexandre
Published: March 2024

Abstract
Expression of class III β-tubulin (βIII-tubulin) correlates with tumor progression and resistance to taxane-based therapies for several human malignancies, but its use as a biomarker of tumor behavior in prostate cancer (PCa) remains largely unexplored. Here, we describe βIII-tubulin immunohistochemical staining patterns of prostate tumors obtained from a broad spectrum of PCa patients, some of whom subsequently received docetaxel therapy for castration-resistant PCa (CRPC). Elevated βIII-tubulin expression was significantly associated with tumor aggressiveness in PCa patients with presumed localized disease, as it was found to be an independent marker of biochemical recurrence after treatment. Additionally, βIII-tubulin expression in tumor cells was an independent predictor of lower overall survival for patients receiving docetaxel-based chemotherapy for CRPC. Manipulation of βIII-tubulin expression in human PCa cell lines using a human βIII-tubulin expression vector or βIII-tubulin small interfering RNA altered cell survival in response to docetaxel treatment in a manner that supports a role for βIII-tubulin expression as a mediator of PCa cell resistance to docetaxel therapy. Our findings suggest a role for βIII-tubulin as candidate theranostic biomarker to predict the response to docetaxel-based chemotherapy as well as to target for treatment of docetaxel-resistant CRPC. Cancer Res; 70(22); 9253–64. ©2010 AACR.
Data from Notch3 Activation Promotes Invasive Glioma Formation in a Tissue Site-Specific Manner
Authors: Pierfelice Tarran J. , Schreck Karisa C. , Dang Louis , Asnaghi Laura , Gaiano Nicholas , Eberhart Charles G.
Published: March 2024

Abstract
Although Notch signaling has been widely implicated in neoplastic growth, direct evidence for in vivo initiation of neoplasia by the pathway in murine models has been limited to tumors of lymphoid, breast, and choroid plexus cells. To examine tumorigenic potential in the eye and brain, we injected retroviruses encoding activated forms of Notch1, Notch2, or Notch3 into embryonic mice. Interestingly, the majority of animals infected with active Notch3 developed proliferative lesions comprised of pigmented ocular choroid cells, retinal and optic nerve glia, and lens epithelium. Notch3-induced lesions in the choroid, retina, and optic nerve were capable of invading adjacent tissues, suggesting that they were malignant tumors. Although Notch3 activation induced choroidal tumors in up to 67% of eyes, Notch1 or Notch2 activation never resulted in such tumors. Active forms of Notch1 and Notch2 did generate a few small proliferative glial nodules in the retina and optic nerve, whereas Notch3 was 10-fold more efficient at generating growths, many of which were large invasive gliomas. Expression of active Notch1/Notch3 chimeric receptors implicated the RBPjk-association molecule and transactivation domains of Notch3 in generating choroidal and glial tumors, respectively. In contrast to our findings in the optic nerve and retina, introduction of active Notch receptors, including Notch3, into the brain never caused glial tumors. Our results highlight the differential ability of Notch receptor paralogs to initiate malignant tumor formation, and suggest that glial precursors of the optic nerve, but not the brain, are susceptible to transformation by Notch3. Cancer Res; 71(3); 1115–25. ©2011 AACR.
Data from Critical Roles of Mucin 1 Glycosylation by Transactivated Polypeptide N-Acetylgalactosaminyltransferase 6 in Mammary Carcinogenesis
Authors: Park Jae-Hyun , Nishidate Toshihiko , Kijima Kyoko , Ohashi Takao , Takegawa Kaoru , Fujikane Tomoko , Hirata Koichi , Nakamura Yusuke , Katagiri Toyomasa
Published: March 2024

Abstract
The structure of O-glycosylated proteins is altered in breast cancer cells, but the mechanisms of such an aberrant modification have been largely unknown. We here report critical roles of a novel druggable target, polypeptide N-acetylgalactosaminyltransferase 6 (GALNT6), which is upregulated in a great majority of breast cancers and encodes a glycosyltransferase responsible for initiating mucin-type O-glycosylation. Knockdown of GALNT6 by small interfering RNA significantly enhanced cell adhesion function and suppressed the growth of breast cancer cells. Western blot and immunostaining analyses indicated that wild-type GALNT6 protein could glycosylate and stabilize an oncoprotein mucin 1 (MUC1), which was upregulated with GALNT6 in breast cancer specimens. Furthermore, knockdown of GALNT6 or MUC1 led to similar morphologic changes of cancer cells accompanied by the increase of cell adhesion molecules β-catenin and E-cadherin. Our findings implied that overexpression of GALNT6 might contribute to mammary carcinogenesis through aberrant glycosylation and stabilization of MUC1 and that screening of GALNT6 inhibitors would be valuable for the development of novel therapeutic modalities against breast cancer. Cancer Res; 70(7); 2759–69
Data from HER Kinase Axis Receptor Dimer Partner Switching Occurs in Response to EGFR Tyrosine Kinase Inhibition despite Failure to Block Cellular Proliferation
Authors: Jain Anjali , Penuel Elicia , Mink Sheldon , Schmidt Joanna , Hodge Amanda , Favero Kristin , Tindell Charles , Agus David B.
Published: March 2024

Abstract
The human epidermal receptor (HER) axis consists of a dynamic, interconnected family of receptors that make critical contributions to a number of malignancies. Therapeutics targeting epidermal growth factor receptor (EGFR) are unable to effectively inhibit tumor growth in a majority of cases. These tumors are assumed to possess primary resistance to anti-EGFR therapies, but the consequence of inhibiting EGFR in these tumors is unclear. We established isogenic cell lines by prolonged gefitinib treatment at concentrations that are in excess of that which is required for complete EGFR kinase inhibition but only minimally affected growth. Subsequently, we monitored the ligand-dependent HER profiles based on receptor expression, phosphorylation, and dimerization in conjunction with measurements of cellular susceptibility to gefitinib. Chronic EGFR kinase inhibition rapidly switched the HER network from dependence on EGFR to HER2. However, both receptors activated the critical signaling proteins AKT and mitogen-activated protein kinase, and in both cases, HER3 was the common association partner. Remarkably, the switch in receptor dimers caused diminished susceptibility to EGFR-targeted inhibitors gefitinib and cetuximab but acquired susceptibility to the HER2-targeted inhibitor pertuzumab. Overall, our study indicates that the EGFR pathway is responsive to EGFR inhibiting therapies that are not dependent on EGFR for their growth and survival, thus challenging the current definition of primary therapeutic resistance. Furthermore, EGFR kinase inhibition induces HER kinase receptors to engage in alternative dimerization that can ultimately influence therapeutic selection and responsiveness. Cancer Res; 70(5); 1989–99
Data from Targeted Radiosensitization of Cells Expressing Truncated DNA Polymerase β
Authors: Neijenhuis Sari , Verwijs-Janssen Manon , van den Broek Lenie J. , Begg Adrian C. , Vens Conchita
Published: March 2024

Abstract
Ionizing radiation (IR) is an effective anticancer treatment, although failures still occur. To improve radiotherapy, tumor-targeted strategies are needed to increase radiosensitivity of tumor cells, without influencing normal tissue radiosensitivity. Base excision repair (BER) and single-strand break repair (SSBR) contribute to the determination of sensitivity to IR. A crucial protein in BER/SSBR is DNA polymerase β (polβ). Aberrant polβ expression is commonly found in human tumors and leads to inhibition of BER. Here, we show that truncated polβ variant (polβ-Δ)–expressing cells depend on homologous recombination (HR) for survival after IR, indicating that a considerable fraction of polβ-Δ–induced lesions are subject to repair by HR. Increased sensitization was found not to result from involvement in DNA-dependent protein kinase–dependent nonhomologous end joining, the other major double-strand break repair pathway. Caffeine and the ATM inhibitor Ku55933 cause polβ-Δ–dependent radiosensitization. Consistent with the observed HR dependence and the known HR-modulating activity of ATM, polβ-Δ–expressing cells showed increased radiosensitization after BRCA2 knockdown that is absent under ATM-inhibited conditions. Our data suggest that treatment with HR modulators is a promising therapeutic strategy for exploiting defects in the BER/SSBR pathway in human tumors. Cancer Res; 70(21); 8706–14. ©2010 AACR.
Data from Increase of Plasma VEGF after Intravenous Administration of Bevacizumab Is Predicted by a Pharmacokinetic Model
Authors: Stefanini Marianne O. , Wu Florence T. H. , Mac Gabhann Feilim , Popel Aleksander S.
Published: March 2024

Abstract
Vascular endothelial growth factor (VEGF) is one of the most potent cytokines targeted in antiangiogenic therapies. Bevacizumab, a recombinant humanized monoclonal antibody to VEGF, is being used clinically in combination with chemotherapy for colorectal, non–small cell lung and breast cancers, and as a single agent for glioblastoma and is being tested for other types of cancer in numerous clinical trials. It has been reported that the intravenous injection of bevacizumab leads to an increase of plasma VEGF concentration in cancer patients. The mechanism responsible for this counterintuitive increase has not been elucidated, although several hypotheses have been proposed. We use a multiscale systems biology approach to address this problem. We have constructed a whole-body pharmacokinetic model comprising three compartments: blood, normal tissue, and tumor tissue. Molecular interactions among VEGF-A family members, their major receptors, the extracellular matrix, and an anti-VEGF ligand are considered for each compartment. Diffusible molecules extravasate, intravasate, are removed from the healthy tissue through the lymphatics, and are cleared from the blood. Cancer Res; 70(23); 9886–94. ©2010 AACR.
Data from Peptide Vaccination Breaks Tolerance to HER-2/neu by Generating Vaccine-Specific FasL+ CD4+ T Cells: First Evidence for Intratumor Apoptotic Regulatory T Cells
Authors: Gritzapis Angelos D. , Voutsas Ioannis F. , Lekka Eftychia , Papamichail Michael , Baxevanis Constantin N.
Published: March 2024

Abstract
BALB/c mice transgenic (Tg) for the transforming rat neu oncogene (BALB-neuT) are genetically predestined to develop mammary carcinogenesis in a process similar to that in humans. We crossed HLA-A2.1/HLA-DR1 (A2.1/DR1) Tg mice with BALB-neuT mice to generate A2.1/DR1 × BALB-neuT triple Tg (A2.1/DR1 × neuT+) mice, which represent an improvement over BALB-neuT mice for evaluating vaccination regimens to overcome tolerance against HER-2/neu. A vaccine formulation strategy, consisting of synthetic peptides from the rat HER-2/neu oncogene combined with granulocyte macrophage colony-stimulating factor, was highly effective in preventing the growth of established transplantable tumors in male A2.1/DR1 × neuT+ mice. Vaccination with HER-2(435–443) (p435) CTL peptide alone induced weak antitumor responses, which were characterized by increased numbers of regulatory T cells (Treg) and low numbers of vaccine-specific CD8+ CTL and helper T cells (Th). The administration of p435 plus HER-2(776–790) (p776; helper peptide) reversed this situation, inducing functionally active, peptide-specific CTL and Th. There was a striking change in the intratumoral balance of Tregs (decrease) and vaccine-specific Th (increase) that directly correlated with tumor rejection. Intratumoral administration of anti-FasL antibody promoted tumor growth. The decrease in Tregs (Fas+) was due to apoptosis induced by cell contact with Fas ligand+ (L)+ Th. Mice vaccinated with p435 plus p776 exhibited long-lasting antitumor immunity. Our vaccine regimen also significantly delayed the outgrowth of mammary carcinomas in female A2.1/DR1 × neuT+ animals. We provide a mechanism to overcome tolerance against HER-2/neu, which proposes a combined vaccination with two (Th and CTL) HER-2 peptides against HER-2/neu–expressing tumors. Cancer Res; 70(7); 2686–96
Data from Drugging the PI3 Kinome: From Chemical Tools to Drugs in the Clinic
Authors: Workman Paul , Clarke Paul A. , Raynaud Florence I. , van Montfort Rob L.M.
Published: March 2024

Abstract
The phosphatidylinositide 3-kinase (PI3K) pathway is very commonly activated in a wide range of human cancers and is a major driving force in oncogenesis. One of the class I lipid kinase members of the PI3K family, p110α, is probably the most commonly mutated kinase in the human genome. Alongside genetic, molecular biological, and biochemical studies, chemical inhibitors have been extremely helpful tools in understanding the role of PI3K enzymes in signal transduction and downstream physiological and pathological processes, and also in validating PI3Ks as therapeutic targets. Although they have been valuable in the past, the early and still frequently employed inhibitors, wortmannin and LY294002, have significant limitations as chemical tools. Here, we discuss the case history of the discovery and properties of an increasingly used chemical probe, the pan-class I PI3K and mammalian target of rapamycin (mTOR) inhibitor PI-103 (a pyridofuropyrimidine), and its very recent evolution into the thienopyrimidine drug GDC-0941, which exhibits excellent oral anticancer activity in preclinical models and is now undergoing phase I clinical trials in cancer patients. We also illustrate the impact of structural biology on the design of PI3K inhibitors and on the interpretation of their effects. The challenges and outlook for drugging the PI3 kinome are discussed in the more general context of the role of structural biology and chemical biology in innovative drug discovery. Cancer Res; 70(6); 2146–57
Data from Higher miRNA Tolerance in Immortal Li-Fraumeni Fibroblasts with Abrogated Interferon Signaling Pathway
Authors: Li Qunfang , Tainsky Michael A.
Published: March 2024

Abstract
The IFN pathway is abrogated in fibroblasts from Li-Fraumeni syndrome (LFS) patients during spontaneous cellular immortalization, a necessary step in carcinogenesis. Microarray profiling of differentially expressed microRNAs (miRNA) revealed that most miRNAs were upregulated in IFN pathway–defective MDAH087-10 fibroblasts compared with MDAH087-N cells with relatively normal IFN signaling. Overexpression of Dicer, a critical enzyme in miRNA biogenesis, promoted cell growth and colony formation in MDAH087-10 cells. However, double-stranded miRNA produced by Dicer enhanced the expression of IFN-stimulated genes in MDAH087-N cells resulting in significant cell death and reduced cell growth. Furthermore, manipulation of the IFN pathway in immortal LFS fibroblasts through transcription factor IRF7 reversed their response to Dicer overexpression due to changed IFN pathway activity. Dicer overexpressing MDAH087-N cells contained lower levels of miRNA than vector control, and conversely much higher miRNA expression was detected in Dicer-transfected MDAH087-10 cells. Therefore, cells with a defective IFN pathway have a higher miRNA tolerance than cells with normal IFN pathway. This work indicates for the first time that the IFN pathway as mediated through the transcription factor IRF7 must be disrupted to permit miRNA upregulation to occur in early carcinogenesis. The IFN pathway appears to provide a checkpoint for miRNA level tolerance and its abrogation leads to cellular immortalization. Cancer Res; 71(1); 255–65. ©2010 AACR.
Data from RBCK1 Drives Breast Cancer Cell Proliferation by Promoting Transcription of Estrogen Receptor α and Cyclin B1
Authors: Gustafsson Nina , Zhao Chunyan , Gustafsson Jan-Åke , Dahlman-Wright Karin
Published: March 2024

Abstract
Cell cycle regulatory pathways in breast cancer are incompletely described. Here, we report an important role in estrogen receptor α (ERα)–positive breast cancer cells for the protein kinase C1 (PKC1)–interacting protein RBCK1 in supporting cell cycle progression by driving transcription of ERα and cyclin B1. RBCK1-depleted cells exhibited increased accumulation in G2-M phase of the cell cycle, decreased proliferation, and reduced mRNA levels for ERα and its target genes cyclin D1 and c-myc. Chromatin immunoprecipitation revealed that ERα transcription is associated with RBCK1 recruitment to the ERα promoter, suggesting that transcriptional regulation is one mechanism by which RBCK1 affects ERα mRNA levels. G2-M phase arrest was mediated independently from reduced ERα levels, instead associated with transcriptional inhibition of the key G2-M regulator cyclin B1. In breast tumor samples, there was a positive correlation between levels of RBCK1, ERα, and cyclin B1 mRNA levels. Our findings suggest that RBCK1 regulates cell cycle progression and proliferation of ERα-positive breast cancer cells by supporting transcription of ERα and cyclin B1. Cancer Res; 70(3); 1265–74
Data from Preclinical Evaluation of Radiation and Perifosine in a Genetically and Histologically Accurate Model of Brainstem Glioma
Authors: Becher Oren J. , Hambardzumyan Dolores , Walker Talia R. , Helmy Karim , Nazarian Javad , Albrecht Steffen , Hiner Rebecca L. , Gall Sarah , Huse Jason T. , Jabado Nada , MacDonald Tobey J. , Holland Eric C.
Published: March 2024

Abstract
Brainstem gliomas (BSG) are a rare group of central nervous system tumors that arise mostly in children and usually portend a particularly poor prognosis. We report the development of a genetically engineered mouse model of BSG using the RCAS/tv-a system and its implementation in preclinical trials. Using immunohistochemistry, we found that platelet-derived growth factor (PDGF) receptor α is overexpressed in 67% of pediatric BSGs. Based on this observation, we induced low-grade BSGs by overexpressing PDGF-B in the posterior fossa of neonatal nestin tv-a mice. To generate high-grade BSGs, we overexpressed PDGF-B in combination with Ink4a-ARF loss, given that this locus is commonly lost in high-grade pediatric BSGs. We show that the likely cells of origin for these mouse BSGs exist on the floor of the fourth ventricle and cerebral aqueduct. Irradiation of these high-grade BSGs shows that although single doses of 2, 6, and 10 Gy significantly increased the percent of terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling (TUNEL)–positive nuclei, only 6 and 10 Gy significantly induce cell cycle arrest. Perifosine, an inhibitor of AKT signaling, significantly induced TUNEL-positive nuclei in this high-grade BSG model, but in combination with 10 Gy, it did not significantly increase the percent of TUNEL-positive nuclei relative to 10 Gy alone at 6, 24, and 72 hours. Survival analysis showed that a single dose of 10 Gy significantly prolonged survival by 27% (P = 0.0002) but perifosine did not (P = 0.92). Perifosine + 10 Gy did not result in a significantly increased survival relative to 10 Gy alone (P = 0.23). This PDGF-induced BSG model can serve as a preclinical tool for the testing of novel agents. Cancer Res; 70(6); 2548–57
Data from Interaction of Developmental Transcription Factor HOXC11 with Steroid Receptor Coactivator SRC-1 Mediates Resistance to Endocrine Therapy in Breast Cancer
Authors: McIlroy Marie , McCartan Damian , Early Sarah , Gaora Peadar Ó , Pennington Stephen , Hill Arnold D.K. , Young Leonie S.
Published: March 2024

Abstract
Mechanisms of acquired resistance to endocrine therapy in breast cancer, a major clinical challenge, are poorly understood. We have used a mass spectrometry–based screen to identify proteins that are associated with the endocrine-resistant phenotype. In this study, we report the identification of a novel pathway of resistance to endocrine therapy involving interactions of the developmental transcription HOXC11 with the steroid receptor coactivator protein SRC-1, which is a strong predictor of reduced disease-free survival in breast cancer patients. HOXC11 and SRC-1 cooperate to regulate expression of the calcium-binding protein S100β in resistant breast cancer cells. Nuclear HOXC11 and S100β were found to strongly predict poor disease-free survival in breast cancer patients (n = 560; hazard ratios: 5.79 and 5.82, respectively; P < 0.0001). Elevated serum levels of S100β detected in patients also predicted reduced disease-free survival (n = 80; hazard ratio: 5.3; P = 0.004). Our findings define a biomolecular interaction network that drives an adaptive response to endocrine therapy with negative consequences for survival in breast cancer. Cancer Res; 70(4); 1585–94