Trisomy 14 mosaicism is a rare chromosomal abnormality with distinct and recognizable clinical features. We report a patient with presumed retinal dystrophy having diffuse retinal pigment epithelial abnormalities, which has not been previously reported in association with trisomy 14. This case expands the clinical spectrum of this rare entity.
doi:10.3341/kjo.2012.26.4.316
PMCID: PMC3408541
PMID: 22870035
Retinal dystrophies; Trisomy 14; Trisomy 14 mosaicism
Background
Cadmium(Cd), a heavy metal, which has a potent harmful effects, is a highly stress-inducible material that is robustly expressed following disruption of homeostasis in the endoplasmic reticulum (ER) (so-called ER stress). The mechanism Cd induced cell death of neuroblastoma cells complex, involving cellular signaling pathways as yet incompletely defined but, in part, involving the generation of reactive oxygen species (ROS). Several studies have correlated GADD153 expression with cell death, but a mechanistic link between GADD153 and apoptosis has never been demonstrated.
Results
SH-SY5Y cells were treated Cd led to increase in intracellular ROS levels. ROS generation is not consistent with intracellular [Ca2+]. The exposure of neuroblastoma cells to Cd led to increase in intracellular GADD153 and Bak levels in a doses and time dependent manner. The induction of these genes by Cd was attenuated by NAC. Cd-induced apoptosis is decreased in GADD153 knockdown cells compared with normal cells. The effect of GADD153 on the binding of C/EBP to the Bak promoters were analyzed ChIP assay. Basal constitutive GADD153 recruitment to the –3,398/–3,380 region of the Bak promoter is observed in SH-SY5Y cells.
Conclusions
The exposure of SH-SY5Y cells to Cd led to increase in intracellular ROS levels in a doses and time dependent manner. The generation of ROS result in the induction of GADD153 is causative of cadmium-induced apoptosis. GADD153 regulates Bak expression by its binding to promoter region (between −3,398 and −3,380). Therefore, we conclude that GADD153 sensitizes cells to ROS through mechanisms that involve up-regulation of BAK and enhanced oxidant injury.
doi:10.1186/1471-2121-14-4
PMCID: PMC3563515
PMID: 23339468
Cadmium; ROS; ER; Bak
Purpose
To describe the ophthalmoscopic features and natural history in a case series of eyes that developed intraocular hemorrhages associated with perinatal distress and to evaluate their clinical courses.
Methods
A retrospective chart review of 289 neonates with a medical history of perinatal distress was conducted. Among these 289 patients (578 eyes), 29 eyes of 17 neonates were found to have had retinal hemorrhages or vitreous hemorrhages (VH). A comprehensive chart review, including details of fundoscopic findings and perinatal history, was conducted.
Results
Intraocular hemorrhage was present in 5.5% of the patients. Most hemorrhages (82.7%) were intraretinal. In our population, 17% (n = 5) of hemorrhages resolved within two weeks, but 31% (n = 9) did not resolve even after four weeks. Most hemorrhages spontaneously resolved without any specific sequelae; however, one infant's dense unilateral VH persisted up to three months after birth. When the patient was seen again at 3.5 years of age, she had developed axial myopia and severe amblyopia of the involved eye.
Conclusions
In asphyxiated newborns, the possibility of intraocular hemorrhages should be considered. Long-standing, dense hemorrhages obscuring the macula may lead to severe vision deprivation amblyopia. Therefore, ophthalmic examination should be considered in neonates with perinatal distress, and close observation is necessary for hemorrhages that do not resolve in this amblyogenic age group.
doi:10.3341/kjo.2011.25.5.311
PMCID: PMC3178764
PMID: 21976937
Newborn infant; Perinatal distress; Retinal hemorrhage; Vitreous hemorrhage
Background. Although studies have shown that the use of complementary and alternative medicine (CAM) is common in cancer patients, few surveys have assessed CAM use and associated factors in various cancers in Korea. Objectives. We explored factors predicting CAM use among a nationally representative sample of cancer patients. Methods. In total, 2,661 cancer patients were administered questionnaires about their CAM use and factors that might predict CAM use including sociodemographics, clinical and quality-of-life factors, time since diagnosis, trust in physicians, trust in hospitals, satisfaction, and informational needs. Data were analyzed using Pearson's χ2
tests and multivariate logistic regression analysis. Results. Overall, 25.5% reported that they had used or were using CAM. Higher income, presence of metastasis, longer time since diagnosis, less trust in hospitals, lower overall satisfaction, and higher degree of informational need were significantly associated with CAM use. Conclusions. The use of CAM in patients with cancer can be interpreted as an attempt to explore all possible options, expression of an active coping style, or expression of unmet needs in the cancer care continuum. Physicians need to openly discuss the use of CAM with their patients and identify whether they have other unmet supportive needs.
doi:10.1155/2012/212386
PMCID: PMC3544541
PMID: 23346192
Suh, Beomseok | Shin, Dong Wook | Kim, So Young | Park, Jae-Hyun | Chang, Weon Young | Lim, Seung Pyung | Yim, Chang-Yeol | Cho, Be-Long | Park, Eun-Cheol | Park, Jong-Hyock
Background
While knowledge and risk perception have been associated with screening for second primary cancer (SPC), there are no clinically useful indicators to identify who is at risk of not being properly screened for SPC. We investigated whether the mode of primary cancer detection (i.e. screen-detected vs. non-screen-detected) is associated with subsequent completion of all appropriate SPC screening in cancer survivors.
Methods
Data were collected from cancer patients treated at the National Cancer Center and nine regional cancer centers across Korea. A total of 512 cancer survivors older than 40, time since diagnosis more than 2 years, and whose first primary cancer was not advanced or metastasized were selected. Multivariate logistic regression was used to examine factors, including mode of primary cancer detection, associated with completion of all appropriate SPC screening according to national cancer screening guidelines.
Results
Being screen-detected for their first primary cancer was found to be significantly associated with completion of all appropriate SPC screening (adjusted odds ratio, 2.13; 95% confidence interval, 1.36–3.33), after controlling for demographic and clinical variables. Screen-detected cancer survivors were significantly more likely to have higher household income, have other comorbidities, and be within 5 years since diagnosis.
Conclusions
The mode of primary cancer detection, a readily available clinical information, can be used as an indicator for screening practice for SPC in cancer survivors. Education about the importance of SPC screening will be helpful particularly for cancer survivors whose primary cancer was not screen-detected.
doi:10.1186/1471-2407-12-557
PMCID: PMC3517745
PMID: 23181637
Cancer survivor; Second primary cancer; Screening; Mode of detection; Screen-detected
Background
Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item.
Methods
We collected 811,920 and 669,750 paired (present and previous) test results for 27 clinical chemistry test items from inpatients and outpatients, respectively. We devised new decision criteria for the selection of delta check methods based on the ratio of the delta difference to the width of the reference range (DD/RR). Delta check methods based on these criteria were compared with those based on the CV% of the absolute delta difference (ADD) as well as those reported in 2 previous studies.
Results
The delta check methods suggested by new decision criteria based on the DD/RR ratio corresponded well with those based on the CV% of the ADD except for only 2 items each in inpatients and outpatients. Delta check methods based on the DD/RR ratio also corresponded with those suggested in the 2 previous studies, except for 1 and 7 items in inpatients and outpatients, respectively.
Conclusions
The DD/RR method appears to yield more feasible and intuitive selection criteria and can easily explain changes in the results by reflecting both the biological variation of the test item and the clinical characteristics of patients in each laboratory. We suggest this as a measure to determine delta check methods.
doi:10.3343/alm.2012.32.5.345
PMCID: PMC3427822
PMID: 22950070
Delta check; Detection methods; Reference range; Decision criteria
A 61-year-old man with no history of malignancy presented with a rapidly expanding left periorbital mass, first noticed one month prior to presentation. The mass was firm, and a pus-like discharge drained spontaneously from the center of the lesion. A biopsy was performed, and histopathology confirmed squamous cell carcinoma. Systemic evaluation revealed that the patient had a primary esophageal squamous cell carcinoma with multiple metastases. The prognosis of orbital metastasis is generally poor, and this patient expired after one month of conservative treatment.
doi:10.3341/kjo.2010.24.2.123
PMCID: PMC2851000
PMID: 20379463
Abscess; Orbital neoplasms; Squamous cell carcinoma
Purpose
The aim of this study was to develop an appropriate nursing information guideline according to corrected age, after investigating parents' concerns about the growth, development, and diseases of their premature infants after discharge from the neonatal intensive care unit (NICU).
Methods
The parents of premature infants (birth weight, <2,500 g; gestational age, <37 weeks) who went to a neonatal follow-up clinic after NICU discharge at Seoul St. Mary's Hospital from January 2005 to December 2009, were asked with regard to their concerns about their infants through a questionnaire survey. The results of physical examinations, including body measurements and neurodevelopmental status at 4, 8, 12, and 18 months of corrected age, were retrospectively reviewed in 390 infants.
Results
The most common parental concerns were developmental delay, poor growth, and feeding and nutritional problems. Parental concerns about developmental delay, growth failure in improvement in body weight and length, and overweightness were high in specificity but very low in sensitivity. After NICU discharge, 30% of premature infants experienced infectious diseases before 18 months of corrected age, the most common of which was respiratory tract infection.
Conclusion
For guiding of premature infants in outpatient day clinics after NICU discharge, it is necessary to identify the parents' highest concerns, to educate them about the possibilities of growth and neurodevelopmental disabilities in their infants and to provide them with handouts containing guidelines on the management of infectious diseases, especially respiratory infections.
doi:10.3345/kjp.2012.55.8.272
PMCID: PMC3433563
PMID: 22977439
Premature infant; Follow-up; Questionnaire; Guidance; Neonatal intensive care units
The purposes of this study were to determine phenolic compounds and to evaluate antioxidant activities of plums (Soldam, Oishiwase and Formosa). Soldam contains the highest amount of total phenolics among cultivars (Formosa: 4.0%, Oishiwase: 3.3%, Soldam: 6.4% for total phenolic) as well as the total flavonoids of which constituents were mainly myricetin and anthocyanidin. The antioxidant activities were measured by DPPH, ABTS radical scavenging, and SOD-like activities. The DPPH radical scavenging activity of Korean plum extracts (200 µg/mL) showed more than 43%, and the Soldam turned out to be the highest : ID50 value: 160-177 µg/mL for Formosa and Oishiwase; 58-64 µg/mL for Soldam. The ABTS radical scavenging activity of Korean plum extracts (200 µg/mL) was found to be more than 50%. The SOD-like activity of Korean plum extracts (200 µg/mL) showed more than 70%. Among three kinds of cultivars, Soldam had the highest antioxidant activity. The nitrite scavenging activity of Soldam was 61.5%, which is the highest, compared with that of the other cultivars, about 50%. From these results, Korean plums turned out to be phytochemical rich fruit as well as to show high antioxidant activities.
doi:10.4162/nrp.2012.6.4.277
PMCID: PMC3439570
PMID: 22977680
Antioxidant activity; phenolic compounds; oriental plums
Multiple treatment modalities, including topical and systemic corticosteroid and phototherapy, have been used in treatment of patients with atopic dermatitis. However, long-term corticosteroid therapy may have various adverse effects. The purpose of this study was to investigate the therapeutic efficacy and safety of bath therapy using green tea extracts for treatment of patients with atopic dermatitis. A total of four patients with atopic dermatitis were enrolled in this study. A Malassezia multiplex detection kit was used in performance of multiplex PCR on clinical isolates, which confirmed Malassezia sympodialis. Subjects underwent treatment with bath therapy using green tea extracts three times per wk for a period of 4 wk. Assessment using the scoring atopic dermatitis (SCORAD) index, the visual analogue scale for pruritus, and transepidermal water loss was performed weekly. Laboratory tests were performed before and after treatment. All patients showed marked improvement on the mean SCORAD and visual analogue scale, and a significant decrease in the mean values of serum eosinophil counts was observed after treatment. Bath therapy with green tea extract is an effective, safe, and nonsteroidal therapy for treatment of patients with atopic dermatitis associated with Malassezia sympodialis.
doi:10.5941/MYCO.2012.40.2.124
PMCID: PMC3408302
PMID: 22870055
Atopic dermatitis; Bath therapy; Catechin; Green tea extract
doi:10.5045/kjh.2012.47.1.7
PMCID: PMC3317475
PMID: 22479272
Several common neuropsychiatric disorders (e.g., obsessive-compulsive disorder, Tourette syndrome (TS), autistic spectrum disorder) are associated with unpleasant bodily sensations that are perceived as an urge for action. Similarly, many of our everyday behaviors are also characterized by bodily sensations that we experience as urges for action. Where do these urges originate? In this paper, we consider the nature and the functional anatomy of “urges-for-action,” both in the context of everyday behaviors such as yawning, swallowing, and micturition, and in relation to clinical disorders in which the urge-for-action is considered pathological and substantially interferes with activities of daily living (e.g., TS). We review previous frameworks for thinking about behavioral urges and demonstrate that there is considerable overlap between the functional anatomy of urges associated with everyday behaviors such as swallowing, yawning, and micturition, and those urges associated with the generation of tics in TS. Specifically, we show that the limbic sensory and motor regions—insula and mid-cingulate cortex—are common to all of these behaviors, and we argue that this “motivation-for-action” network should be considered distinct from an “intentional action” network, associated with regions of premotor and parietal cortex, which may be responsible for the perception of “willed intention” during the execution of goal-directed actions.
doi:10.1080/17588928.2011.604717
PMCID: PMC3259619
PMID: 22299020
Urge; Urge-for-action; Habit; Insula; Tourette syndrome; Action
The purpose of this study was to define a one-portion size of food frequently consumed by the Koreans aged 65 years or over. From the original 8,631 people who took part in the Forth Korea National Health and Nutrition Examination Survey (KNHANES IV-2) 2008, we analyzed the data on 1,458 persons (16.9%) aged 65 and over, and selected food items consumed based on the intake frequency of 30 or more by all participant. A total of 158 varieties of food items were selected. The portion size of food items was set on the basis of the median amount (50 percentile) in a single intake by a single person. In the cereals category, 13 items were selected, of which the most frequently consumed item was well-polished rice with portion size of 75 g. Among legumes, 7 items were selected, of which the most frequent item was dried black soybean with a portion size of 6 g. Among the 16 groups, the most varied food group (49 items) was vegetables, and among these the most frequently occurring item was garlic (5 g), while among the fruit group, only 11 items were selected, as their intake frequency was low. Fish and shellfish were more frequently consumed by the elderly than meats. The most frequently consumed meat was pork loin, with a portion size of 30 g. In fish and shellfish, the most frequently consumed item was dried and boiled large anchovy with a portion size of 2 g. Portion sizes for food items consumed regularly by the elderly may be conveniently and effectively used in dietary planning and in nutritional education programs, and in assessing the diet intake status of the elderly.
doi:10.4162/nrp.2011.5.6.553
PMCID: PMC3259299
PMID: 22259681
Portion size; Korean elderly; foods frequently consumed
A 47-day-old male infant presented with fever, poor oral intake, irritability, and right-sided bluish buccal swelling. Contrast-enhanced computed tomography of the neck showed a round mass lesion of about 2.0×1.5 cm that suggested abscess formation in the right masticator space. Ultrasound-guided extraoral aspiration of the abscess at the right masseter muscle was successful. Staphylococcus aureus was identified in the culture from the aspirated pus and blood. Appropriate antibiotics were given and the patient recovered. The patient underwent follow-up ultrasonography that showed an improved state of the previously observed right masseter muscle swelling at about 1 month after hospital discharge. A masticator space abscess usually originates from an odontogenic infection in adults. We report a case of masticator space abscess in a 47-day-old infant in whom septicemia without odontogenic infection was suspected.
doi:10.3345/kjp.2011.54.8.350
PMCID: PMC3212706
PMID: 22087203
Abscess; Infant; Bacteremia
Johannessen, Cory M. | Boehm, Jesse S. | Kim, So Young | Thomas, Sapana R. | Wardwell, Leslie | Johnson, Laura A. | Emery, Caroline M. | Stransky, Nicolas | Cogdill, Alexandria P. | Barretina, Jordi | Caponigro, Giordano | Hieronymus, Haley | Murray, Ryan R. | Salehi-Ashtiani, Kourosh | Hill, David E. | Vidal, Marc | Zhao, Jean J. | Yang, Xiaoping | Alkan, Ozan | Kim, Sungjoon | Harris, Jennifer L. | Wilson, Christopher J. | Myer, Vic E. | Finan, Peter M. | Root, David E. | Roberts, Thomas M. | Golub, Todd | Flaherty, Keith T. | Dummer, Reinhard | Weber, Barbara | Sellers, William R. | Schlegel, Robert | Wargo, Jennifer A. | Hahn, William C. | Garraway, Levi A.
Nature
2010;468(7326):968-972.
Oncogenic mutations in the serine/threonine kinase B-RAF are found in 50–70% of malignant melanomas1. Pre-clinical studies have demonstrated that the B-RAFV600E mutation predicts a dependency on the mitogen activated protein kinase (MAPK) signaling cascade in melanoma1–5—an observation that has been validated by the success of RAF and MEK inhibitors in clinical trials6–8. However, clinical responses to targeted anticancer therapeutics are frequently confounded by de novo or acquired resistance9–11. Identification of resistance mechanisms in a manner that elucidates alternative ‘druggable’ targets may inform effective long-term treatment strategies12. Here, we expressed ~600 kinase and kinase-related open reading frames (ORFs) in parallel to functionally interrogate resistance to a selective RAF kinase inhibitor. We identified MAP3K8 (COT/TPL2) as a MAPK pathway agonist that drives resistance to RAF inhibition in B-RAFV600E cell lines. COT activates ERK primarily through MEK-dependent mechanisms that do not require RAF signaling. Moreover, COT expression is associated with de novo resistance in B-RAFV600E cultured cell lines and acquired resistance in melanoma cells and tissue obtained from relapsing patients following treatment with MEK or RAF inhibition. We further identify combinatorial MAPK pathway inhibition or targeting of COT kinase activity as possible therapeutic strategies for reducing MAPK pathway activation in this setting. Together, these results provide new insights into resistance mechanisms involving the MAPK pathway and articulate an integrative approach through which high-throughput functional screens may inform the development of novel therapeutic strategies.
doi:10.1038/nature09627
PMCID: PMC3058384
PMID: 21107320
Kalender, Adem | Selvaraj, Anand | Kim, So Young | Gulati, Pawan | lé, Sophie Br | Viollet, Benoit | Kemp, Bruce | Bardeesy, Nabeel | Dennis, Patrick | Schlager, John J. | Marette, André | Kozma, Sara C. | Thomas, George
Dysfunctional mTORC1 signaling is associated with a number of human pathologies owing to its central role in controlling cell growth, proliferation, and metabolism. Regulation of mTORC1 is achieved by the integration of multiple inputs, including those of mitogens, nutrients, and energy. It is thought that agents that increase the cellular AMP/ATP ratio, such as the anti-diabetic biguanides metformin and phenformin, inhibit mTORC1 through AMPK activation of TSC1/2-dependent or -independent mechanisms. Unexpectedly, we found that biguanides inhibit mTORC1 signaling, not only in the absence of TSC1/2, but also in the absence of AMPK. Consistent with these observations, in two distinct pre-clinical models of cancer and diabetes, metformin acts to suppress mTORC1 signaling in an AMPK-independent manner. We found that the ability of biguanides to inhibit mTORC1 activation and signaling is, instead, dependent on the Rag GTPases.
doi:10.1016/j.cmet.2010.03.014
PMCID: PMC3081779
PMID: 20444419
Kang, Ji-Yeon | Kim, So-Young | Kim, Dooil | Kim, Dong-Hyun | Shin, Sun-Mi | Park, Sun-Ha | Kim, Keon-Hee | Jung, Heung-Chae | Pan, Jae-Gu | Joung, Young Hee | Chi, Youn-Tae | Chae, Ho Zoon | Ahn, Taeho | Yun, Chul-Ho
An extreme diversity of substrates and catalytic reactions of cytochrome P450 (P450) enzymes is considered to be the consequence of evolutionary adaptation driven by different metabolic or environmental demands. Here we report the presence of numerous natural variants of P450 BM3 (CYP102A1) within a species of Bacillus megaterium. Extensive amino acid substitutions (up to 5% of the total 1049 amino acid residues) were identified from the variants. Phylogenetic analyses suggest that this P450 gene evolve more rapidly than the rRNA gene locus. It was found that key catalytic residues in the substrate channel and active site are retained. Although there were no apparent variations in hydroxylation activity towards myristic acid (C14) and palmitic acid (C16), the hydroxylation rates of lauric acid (C12) by the variants varied in the range of >25-fold. Interestingly, catalytic activities of the variants are promiscuous towards non-natural substrates including human P450 substrates. It can be suggested that CYP102A1 variants can acquire new catalytic activities through site-specific mutations distal to the active site.
doi:10.1186/2191-0855-1-1
PMCID: PMC3159907
PMID: 21906327
We previously reported two modes of development of acquired TRAIL resistance: early phase and late phase [1]. In these studies, we observed that greater Akt activity and the expression of Bcl-xL were related mainly to the late phase of acquired TRAIL resistance.
Recently we became aware of a possible mechanism of early phase TRAIL resistance development through internalization and degradation of TRAIL receptors (DR4 and DR5). Our current studies demonstrate that TRAIL receptors rapidly diminish at the membrane as well as the cytoplasm within four hours after TRAIL exposure, but recover completely after one or two days. Our studies also reveal that Cbl, a ubiquitously expressed cytoplasmic adaptor protein, is responsible for the rapid degradation of TRAIL receptors; Cbl binds to them and induces mono-ubiquitination of these receptors concurrent with their degeneration soon after TRAIL exposure, creating the early phase of acquired TRAIL resistance.
doi:10.1016/j.cellsig.2009.11.012
PMCID: PMC2973327
PMID: 19932172
c-Cbl; TRAIL; TRAIL receptors; TRAIL resistance
Further advances in the prevention, diagnosis and treatment of cancer requires a more complete knowledge of the molecular mechanisms that program the malignant state. Until recently, identifying and validating genetic alterations in tumors that contribute to cancer involved painstaking efforts focused primarily on single mutations. However, the application of whole genome approaches to the study of cancer now makes it possible to contemplate performing systematic characterizations of the structural basis of cancer by identifying mutations associated with each cancer type. In parallel, recent technological advances also make it possible to methodically characterize the function of putative oncogenes and tumor suppressor genes. The integration of these approaches now provides the means to not only derive a complete molecular description of cancer but will also provide well-validated targets for the development of therapeutic agents.
doi:10.1016/j.bbagen.2009.02.003
PMCID: PMC2692376
PMID: 19364473
Cancer; genomics; mutation; integration
A 59-year-old man was admitted with numbness, pain, and a tingling sensation in both lower legs. He was initially diagnosed with diabetic peripheral neuropathy based on a symptom questionnaire and a quantitative sensory test. Despite symptomatic treatment of diabetic neuropathy, he complained of worsening sensory symptoms and additional motor weakness in both lower extremities. As the motor weakness of both extremities became more aggravated over time, brain and spine imaging tests and a nerve conduction test were performed. The nerve conduction study revealed motor and sensory axonal neuropathy. In his cerebrospinal analysis, albumino-cytologic dissociation, which is compatible to the Gillian-Barre syndrome, was found. Cerebrospinal fluid analysis showed albumino-cytologic dissociation. He was treated with intravenous immunoglobulin and his neurologic deficits were gradually improved.
doi:10.3904/kjim.2010.25.2.217
PMCID: PMC2880698
PMID: 20526398
Diabetes mellitus; Guillain-Barre syndrome; Diabetic neuropathy
Barbie, David A. | Tamayo, Pablo | Boehm, Jesse S. | Kim, So Young | Moody, Susan E. | Dunn, Ian F. | Schinzel, Anna C. | Sandy, Peter | Meylan, Etienne | Scholl, Claudia | Fröhling, Stefan | Chan, Edmond M. | Sos, Martin L. | Michel, Kathrin | Mermel, Craig | Silver, Serena J. | Weir, Barbara A. | Reiling, Jan H. | Sheng, Qing | Gupta, Piyush B. | Wadlow, Raymond C. | Le, Hanh | Hoersch, Sebastian | Wittner, Ben S. | Ramaswamy, Sridhar | Livingston, David M. | Sabatini, David M. | Meyerson, Matthew | Thomas, Roman K. | Lander, Eric S. | Mesirov, Jill P. | Root, David E. | Gilliland, D. Gary | Jacks, Tyler | Hahn, William C.
Nature
2009;462(7269):108-112.
The proto-oncogene KRAS is mutated in a wide array of human cancers, most of which are aggressive and respond poorly to standard therapies. Although the identification of specific oncogenes has led to the development of clinically effective, molecularly targeted therapies in some cases, KRAS has remained refractory to this approach. A complementary strategy for targeting KRAS is to identify gene products that, when inhibited, result in cell death only in the presence of an oncogenic allele1,2. Here we have used systematic RNA interference (RNAi) to detect synthetic lethal partners of oncogenic KRAS and found that the non-canonical IκB kinase, TBK1, was selectively essential in cells that harbor mutant KRAS. Suppression of TBK1 induced apoptosis specifically in human cancer cell lines that depend on oncogenic KRAS expression. In these cells, TBK1 activated NF-κB anti-apoptotic signals involving cREL and BCL-XL that were essential for survival, providing mechanistic insights into this synthetic lethal interaction. These observations identify TBK1 and NF-κB signaling as essential in KRAS mutant tumors and establish a general approach for the rational identification of co-dependent pathways in cancer.
doi:10.1038/nature08460
PMCID: PMC2783335
PMID: 19847166
Bass, Adam J. | Watanabe, Hideo | Mermel, Craig H. | Yu, Soyoung | Perner, Sven | Verhaak, Roel G. | Kim, So Young | Wardwell, Leslie | Tamayo, Pablo | Gat-Viks, Irit | Ramos, Alex H. | Woo, Michele S. | Weir, Barbara A. | Getz, Gad | Beroukhim, Rameen | O’Kelly, Michael | Dutt, Amit | Rozenblatt-Rosen, Orit | Dziunycz, Piotr | Komisarof, Justin | Chirieac, Lucian R. | LaFargue, Christopher J. | Scheble, Veit | Wilbertz, Theresia | Ma, Changqing | Rao, Shilpa | Nakagawa, Hiroshi | Stairs, Douglas B. | Lin, Lin | Giordano, Thomas J. | Wagner, Patrick | Minna, John D. | Gazdar, Adi F. | Zhu, Chang Qi | Brose, Marcia S. | Cecconello, Ivan | Ribeiro, Ulysses | Marie, Suely K. | Dahl, Olav | Shivdasani, Ramesh A. | Tsao, Ming-Sound | Rubin, Mark A. | Wong, Kwok K. | Regev, Aviv | Hahn, William C. | Beer, David G. | Rustgi, Anil K. | Meyerson, Matthew
Lineage survival oncogenes are activated by somatic DNA alterations in cancers arising from the cell lineages in which these genes play a role in normal development.1,2 Here we show that a peak of genomic amplification on chromosome 3q26.33, found in squamous cell carcinomas (SCCs) of the lung and esophagus, contains the transcription factor gene SOX2—which is mutated in hereditary human esophageal malformations3 and necessary for normal esophageal squamous development4, promotes differentiation and proliferation of basal tracheal cells5 and co-operates in induction of pluripotent stem cells.6,7,8
SOX2 expression is required for proliferation and anchorage-independent growth of lung and esophageal cell lines, as shown by RNA interference experiments. Furthermore, ectopic expression of SOX2 cooperated with FOXE1 or FGFR2 to transform immortalized tracheobronchial epithelial cells. SOX2-driven tumors show expression of markers of both squamous differentiation and pluripotency. These observations identify SOX2 as a novel lineage survival oncogene in lung and esophageal SCC.
doi:10.1038/ng.465
PMCID: PMC2783775
PMID: 19801978
Kim, So Young | Dunn, Ian F. | Firestein, Ron | Gupta, Piyush | Wardwell, Leslie | Repich, Kara | Schinzel, Anna C. | Wittner, Ben | Silver, Serena J. | Root, David E. | Boehm, Jesse S. | Ramaswamy, Sridhar | Lander, Eric S. | Hahn, William C. | Blagosklonny, Mikhail V.
Background
Aberrant β-catenin signaling plays a key role in several cancer types, notably colon, liver and breast cancer. However approaches to modulate β-catenin activity for therapeutic purposes have proven elusive to date.
Methodology
To uncover genetic dependencies in breast cancer cells that harbor active β-catenin signaling, we performed RNAi-based loss-of-function screens in breast cancer cell lines in which we had characterized β-catenin activity. Here we identify CSNK1E, the gene encoding casein kinase 1 epsilon (CK1ε) as required specifically for the proliferation of breast cancer cells with activated β-catenin and confirm its role as a positive regulator of β-catenin-driven transcription. Furthermore, we demonstrate that breast cancer cells that harbor activated β-catenin activity exhibit enhanced sensitivity to pharmacological blockade of Wnt/β-catenin signaling. We also find that expression of CK1ε is able to promote oncogenic transformation of human cells in a β-catenin-dependent manner.
Conclusions/Significance
These studies identify CK1ε as a critical contributor to activated β-catenin signaling in cancer and suggest it may provide a potential therapeutic target for cancers that harbor active β-catenin. More generally, these observations delineate an approach that can be used to identify druggable synthetic lethal interactions with signaling pathways that are frequently activated in cancer but are difficult to target with the currently available small molecule inhibitors.
doi:10.1371/journal.pone.0008979
PMCID: PMC2813871
PMID: 20126544
Vasudevan, Krishna M. | Barbie, David A. | Davies, Michael A. | Rabinovsky, Rosalia | McNear, Chontelle J. | Kim, Jessica J. | Hennessy, Bryan T. | Tseng, Hsiuyi | Pochanard, Panisa | Kim, So Young | Dunn, Ian F. | Schinzel, Anna C. | Sandy, Peter | Hoersch, Sebastian | Sheng, Qing | Gupta, Piyush B. | Boehm, Jesse S. | Reiling, Jan H. | Silver, Serena | Lu, Yiling | Stemke-Hale, Katherine | Dutta, Bhaskar | Joy, Corwin | Sahin, Aysegul A. | Gonzalez-Angulo, Ana Maria | Lluch, Ana | Rameh, Lucia E. | Jacks, Tyler | Root, David E. | Lander, Eric S. | Mills, Gordon B. | Hahn, William C. | Sellers, William R. | Garraway, Levi A.
Summary
Dysregulation of the phosphatidylinositol 3-kinase (PI3K) signaling pathway occurs commonly in human cancer. PTEN tumor suppressor or PIK3CA oncogene mutations both direct PI3K-dependent tumorigenesis largely through activation of the AKT/PKB kinase. However, here we show through phospho-protein profiling and functional genomic studies that many PIK3CA-mutant cancer cell lines and human breast tumors exhibit only minimal AKT activation, and a diminished reliance on AKT for anchorage-independent growth. Instead, these cells retain robust PDK1 activation and membrane localization, and exhibit dependency on the PDK1 substrate SGK3. SGK3 undergoes PI3K- and PDK1-dependent activation in PIK3CA-mutant cancer cells. Thus, PI3K may promote cancer through both AKT-dependent and AKT-independent mechanisms. Knowledge of differential PI3K/PDK1 signaling could inform rational therapeutics in cancers harboring PIK3CA mutations.
doi:10.1016/j.ccr.2009.04.012
PMCID: PMC2752826
PMID: 19573809
PI3 kinase; PTEN; AKT; PDK1; SGK3; cancer
Kim, So-Young | Kim, Hak-Ryul | Song, Jung-Sub | Hwang, Ki-Eun | Shin, Jeong-Hyun | Shin, Seoung-Nam | Kim, Dong | Park, Seong-Hoon | Yang, Sei-Hoon | Jeong, Eun-Taik
Pseudoaneurysm due to cancer is uncommon generally and is extremely rare in lung cancer. We report two cases of false aneurysms due to lung cancer that spontaneously regressed upon chemotherapy without intervention. Both patients had squamous cell carcinoma of the lung and the diagnosis of a pseudoaneurysm was made using computed tomography. There was no evidence of severe bronchial hemorrhage and the psuedoaneurysms were small and well-encased. Chemotherapy was performed and the pseudoaneurysms resolved.
doi:10.4143/crt.2009.41.4.237
PMCID: PMC2802847
PMID: 20057971
Aneurysm; False; Lung neoplasms