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1.
J Assoc Nurses AIDS Care ; 31(1): 35-41, 2020.
Article in English | MEDLINE | ID: mdl-30958407

ABSTRACT

Unannounced telephone pill counts are an objective antiretroviral therapy adherence measurement tool, but this method has not been validated in young adults (YA) living with perinatal HIV infection. Perinatally infected YA, recruited from the Child and Adolescent Self-Awareness and Health Study, agreed to unannounced telephone pill counts to measure medication adherence over 4 months and phlebotomy to measure viral load (VL). Differences in pill count adherence scores among YA with a VL of ≤20 versus >20, and demographic differences were assessed. Participants (N = 62) were, on average, 24 years old; 57% were African American, and 40% were Latino. Participants with VL of ≤20 (60%) had significantly higher adherence scores (85% versus 62%; p = .004). Associations were not significant among older YA (range, 25-28 years) or Latinos. Unannounced telephone pill counts are a valid measure of antiretroviral therapy adherence in YA with perinatal HIV infection. Studies with larger samples are needed.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Infectious Disease Transmission, Vertical , Medication Adherence/statistics & numerical data , Telephone , Adolescent , Anti-HIV Agents/administration & dosage , Child , Female , HIV Infections/virology , Health Care Surveys/methods , Humans , Interviews as Topic , Male , Reproducibility of Results , Viral Load/drug effects , Young Adult
2.
J Assoc Nurses AIDS Care ; 29(4): 538-549, 2018.
Article in English | MEDLINE | ID: mdl-29526603

ABSTRACT

As youth with perinatally acquired HIV infection age, there is a need for studies that identify predictors and correlates of sexual risk behaviors. We examined the association between psychiatric disorders and substance use disorders (SUD) with sexual risk behaviors in youth with perinatally acquired HIV infection and perinatally HIV-exposed but uninfected youth. Participants were recruited from four medical centers in New York City. The Diagnostic Interview Schedule for Children and the Adolescent Sexual Behavior Assessment were administered to assess psychiatric disorders and sexual behaviors, respectively. SUD and behavior disorders were correlated with either ever having had penetrative sex or recent condomless sex for participants with perinatally acquired HIV infection only. Results suggest that clinicians should screen and treat patients for SUD and behavioral disorders to reduce sexual risk behaviors in youth with perinatally acquired HIV infection.


Subject(s)
HIV Infections/epidemiology , Mental Disorders/epidemiology , Risk-Taking , Sexual Behavior/psychology , Substance-Related Disorders/epidemiology , Adolescent , Adolescent Behavior/psychology , Cross-Sectional Studies , Female , HIV Infections/complications , HIV Infections/psychology , Humans , Infectious Disease Transmission, Vertical , Longitudinal Studies , Male , Mental Disorders/complications , New York City/epidemiology , Prevalence , Substance-Related Disorders/complications , Substance-Related Disorders/psychology , Unsafe Sex
3.
Pediatr Infect Dis J ; 37(7): 673-677, 2018 07.
Article in English | MEDLINE | ID: mdl-29227462

ABSTRACT

BACKGROUND: Perinatally HIV-infected (PHIV+) adolescents and young adults (AYA) are at risk for suboptimal antiretroviral therapy (ART) adherence and mental health and substance use problems that, in HIV-infected adults, predict nonadherence. Studies on the relationship between psychiatric and substance use disorders (SUD) and adherence among PHIV+ AYA are limited, but may be important for informing evidence-based interventions to promote adherence. METHODS: Data were analyzed from 3 annual follow-up interviews (FU2-FU4, N = 179) in a longitudinal study of PHIV+ AYA. Psychiatric disorders (anxiety, disruptive behavior, mood and SUD) were assessed with the Diagnostic Interview Schedule for Children. Adherence was self-reported missed ART doses within the past week. Viral load (VL) results were abstracted from medical charts. Multiple logistic regression analyzed cross-sectional associations between psychiatric disorders and (1) missed ART dose and (2) VL > 1000 copies/mL. Multiple linear regression assessed associations between psychiatric disorders and proportion of VL values >1000 copies/mL over time. RESULTS: At FU2, 53% of PHIV+ AYA had any psychiatric disorder, 35% missed an ART dose in the past week and 47% had a VL > 1000 copies/mL. At FU2, behavioral disorders were associated with missed dose (P = 0.009) and VL > 1000 (P = 0.019), and mood disorders were associated with missed dose (P = 0.041). At FU4, behavioral disorders were associated with missed dose (P = 0.009). Behavioral disorders (P = 0.041), SUD (P = 0.016) and any disorder (P = 0.008) at FU2 were associated with higher proportion of VLs >1000 across FU2-FU4. CONCLUSIONS: Addressing psychiatric disorder and SUD among PHIV+ AYA may improve ART adherence outcomes in this population. Targeted interventions should be developed and tested.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Medication Adherence , Mental Disorders/complications , Substance-Related Disorders/complications , Viremia/drug therapy , Adolescent , Anti-HIV Agents/administration & dosage , Antiretroviral Therapy, Highly Active , Child , Cognitive Dysfunction/complications , Cross-Sectional Studies , Female , HIV/drug effects , HIV Infections/psychology , Humans , Infectious Disease Transmission, Vertical , Longitudinal Studies , Male , New York City , Surveys and Questionnaires , Viral Load
4.
J Pediatr Psychol ; 42(9): 1006-1015, 2017 10 01.
Article in English | MEDLINE | ID: mdl-28369465

ABSTRACT

Objective: To examine unannounced telephone pill counts as a measure of adherence to antiretroviral therapy among adolescents and young adults living with perinatal HIV infection. Methods: Participants were recruited from an ongoing longitudinal study to complete four monthly, unannounced telephone pill counts. Detailed notes concerning participants' medication habits surrounding adherence were recorded. Results: Two-thirds of 102 eligible participants aged 18-27 years participated; 57% were female, 69% were Black. Blacks and participants with viral loads >40 and >1,000 copies/ml were less likely to participate. Average adherence across calls was 77%. Those who completed all calls averaged significantly higher adherence scores than those who did not. Calls revealed adherence barriers at individual (e.g., medication disorganization), social (e.g., limited support), and system (e.g., pharmacy problems) levels. Conclusions: Despite challenges, this procedure can be implemented with this population and can help identify adherence barriers important for interventions that address medication-taking behaviors.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/psychology , Medication Adherence/statistics & numerical data , Telephone , Adolescent , Adult , Female , Health Behavior , Health Surveys , Humans , Longitudinal Studies , Male , Self Administration/psychology , Social Support , United States , Viral Load , Young Adult
5.
AIDS Behav ; 21(1): 129-140, 2017 Jan.
Article in English | MEDLINE | ID: mdl-26874846

ABSTRACT

Similar to same-age peers, perinatally HIV-infected (PHIV+) youth in the US are engaging in sex, including condomless sex. Understanding decisions about serostatus disclosure to sexual partners is important to domestic and global HIV prevention efforts, since large numbers of PHIV+ children are entering adolescence and becoming sexually active. Using Social Action Theory (SAT) to inform variable selection, we examined correlates of disclosure among 98 PHIV+ adolescents/young adults in New York City. Over half of these youth reported not disclosing to any casual partners (59 %) or to any partners when using condoms (55 %). In bivariate analyses, increased disclosure was associated with older age; being female; earlier age of learning one's serostatus; and increased STD knowledge, disclosure intentions, and parent-child communication. Multiple regression analyses revealed a strong fit with the SAT model. As with adults, disclosure to sexual partners is difficult for PHIV+ youth and challenges prevention efforts. Effective interventions that help youth with disclosure decisions are needed to curb the epidemic.


Subject(s)
HIV Infections/prevention & control , Health Knowledge, Attitudes, Practice , Infectious Disease Transmission, Vertical , Self Disclosure , Sexual Behavior , Sexual Partners , Adolescent , Adult , Communication , Condoms/statistics & numerical data , Disclosure , Female , HIV Infections/transmission , Humans , Intention , Male , New York City , Parent-Child Relations , Regression Analysis , Young Adult
6.
Nat Commun ; 7: 11245, 2016 Apr 13.
Article in English | MEDLINE | ID: mdl-27071537

ABSTRACT

RAS signalling through phosphoinositide 3-kinase (PI3-Kinase) has been shown to have an essential role in tumour initiation and maintenance. RAS also regulates cell motility and tumour invasiveness, but the role of direct RAS binding to PI3-Kinase in this remains uncertain. Here, we provide evidence that disruption of RAS interaction with PI3-Kinase p110α decreases cell motility and prevents activation of Rac GTPase. Analysis of gene expression in cells lacking RAS interaction with p110α reveals increased levels of the extracellular matrix glycoprotein Reelin and activation of its downstream pathway resulting in upregulation of E-cadherin expression. Induction of the Reelin/E-cadherin axis is also observed in Kras mutant lung tumours that are regressing due to blockade of RAS interaction with PI3-Kinase. Furthermore, loss of Reelin correlates with decreased survival of lung and breast cancer patients. Reelin thus plays a role in restraining RAS and PI3-kinase promotion of cell motility and potentially tumour metastasis.


Subject(s)
Cell Adhesion Molecules, Neuronal/metabolism , Cell Movement , Extracellular Matrix Proteins/metabolism , Nerve Tissue Proteins/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Serine Endopeptidases/metabolism , Signal Transduction , ras Proteins/metabolism , Animals , Cadherins/metabolism , Cell Polarity , Enzyme Activation , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice , Protein Binding , Reelin Protein , Up-Regulation , rac1 GTP-Binding Protein/metabolism
7.
J Pediatr Psychol ; 41(3): 277-86, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26698841

ABSTRACT

OBJECTIVE:  To examine longitudinal reciprocal relationships between marijuana use and psychiatric disorders, and identify the role of HIV in a sample (N = 340) of youth perinatally infected with HIV (PHIV+) and youth perinatally exposed but uninfected with HIV (PHIV-) (60.6% PHIV+; 9-16 years at baseline; 51% female). METHODS: Cross-lagged structural equation modeling was used to examine longitudinal associations between changes in marijuana use and changes in any behavioral, mood, and anxiety disorders at three time points across adolescence. RESULTS: Marijuana use predicted behavioral and mood disorders in youth, regardless of HIV status. Behavioral and mood disorders predicted marijuana use for PHIV- youth; behavioral disorders predicted marijuana use for PHIV+ youth. Anxiety disorders and marijuana use were not associated for either group. CONCLUSIONS: For PHIV+ and PHIV- youth, interventions that target early marijuana use may reduce later psychiatric disorders. Similarly, treatment for early behavioral disorders may prevent subsequent marijuana use.


Subject(s)
HIV Infections/epidemiology , Infectious Disease Transmission, Vertical/statistics & numerical data , Marijuana Smoking/epidemiology , Mental Disorders/epidemiology , Pregnancy Complications, Infectious/epidemiology , Adolescent , Child , Comorbidity , Female , Humans , Infant, Newborn , Male , Pregnancy
8.
J Acquir Immune Defic Syndr ; 69 Suppl 1: S16-24, 2015 May 01.
Article in English | MEDLINE | ID: mdl-25867774

ABSTRACT

BACKGROUND: Engagement in HIV care helps to maximize viral suppression, which in turn, reduces morbidity and mortality and prevents further HIV transmission. With more HIV cases than any other US city, New York City reported in 2012 that only 41% of all persons estimated to be living with HIV (PLWH) had a suppressed viral load, whereas nearly three-quarters of those in clinical care achieved viral suppression. Thus, retaining PLWH in HIV care addresses this central goal of both the US National HIV/AIDS Strategy and Governor Cuomo's plan to end the AIDS epidemic in New York State. METHODS: We conducted 80 in-depth qualitative interviews with PLWH in 4 New York City populations that were identified as being inconsistently engaged in HIV medical care: African immigrants, previously incarcerated adults, transgender women, and young men who have sex with men. RESULTS: Barriers to and facilitators of HIV care engagement fell into 3 domains: (1) system factors (eg, patient-provider relationship, social service agencies, transitions between penal system and community), (2) social factors (eg, family and other social support; stigma related to HIV, substance use, sexual orientation, gender identity, and incarceration), and (3) individual factors (eg, mental illness, substance use, resilience). Similarities and differences in these themes across the 4 populations as well as research and public health implications were identified. CONCLUSIONS: Engagement in care is maximized when the social challenges confronted by vulnerable groups are addressed, patient-provider communication is strong, and coordinated services are available, including housing, mental health and substance use treatment, and peer navigation.


Subject(s)
HIV Infections/epidemiology , Patient Acceptance of Health Care , Vulnerable Populations , Adolescent , Adult , Communication , Continuity of Patient Care , Female , HIV Infections/drug therapy , HIV Infections/prevention & control , Humans , Male , Middle Aged , New York City/epidemiology , Primary Health Care , Sexual Behavior , Social Stigma , Social Support , Transgender Persons , Young Adult
9.
AIDS Behav ; 19 Suppl 2: 163-76, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25566763

ABSTRACT

Multimedia technologies offer powerful tools to increase capacity of health workers to deliver standardized, effective, and engaging antiretroviral medication adherence counseling. Masivukeni-is an innovative multimedia-based, computer-driven, lay counselor-delivered intervention designed to help people living with HIV in resource-limited settings achieve optimal adherence. This pilot study examined medication adherence and key psychosocial outcomes among 55 non-adherent South African HIV+ patients, on antiretroviral therapy (ART) for at least 6 months, who were randomized to receive either Masivukeni or standard of care (SOC) counseling for ART non-adherence. At baseline, there were no significant differences between the SOC and Masivukeni groups on any outcome variables. At post-intervention (approximately 5-6 weeks after baseline), -clinic-based pill count adherence data available for 20 participants (10 per intervention arm) showed a 10 % improvement for-participants and a decrease of 8 % for SOC participants. Masivukeni participants reported significantly more positive attitudes towards disclosure and medication social support, less social rejection, and better clinic-patient relationships than did SOC participants. Masivukeni shows promise to promote optimal adherence and provides preliminary evidence that multimedia, computer-based technology can help lay counselors offer better adherence counseling than standard approaches.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Community Health Workers , Counseling/methods , HIV Infections/drug therapy , Medication Adherence , Multimedia , Adult , CD4 Lymphocyte Count , Female , HIV Infections/psychology , Health Knowledge, Attitudes, Practice , Humans , Male , Middle Aged , Patient Education as Topic , Pilot Projects , Program Evaluation , Social Support , South Africa , Treatment Outcome , Viral Load , Young Adult
10.
AIDS Patient Care STDS ; 29(1): 43-51, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25372391

ABSTRACT

We examined youth-caregiver adherence report concordance and association of different adherence self-report items with HIV RNA viral load (VL) in perinatally HIV-infected adolescents assessed in 2003-2008. Youth (n=194; 9-19 years) and their caregivers completed a multi-step 2-day recall, one item on last time medications were missed, and one item on responsibility for managing youths' medications. Across early (9-12 years), middle (13-15 years), and late (16+years) adolescence, both youth and caregivers reported having primary responsibility for youths' medication regimens and demonstrated poor to moderate youth-caregiver concordance on adherence items. Responses to the last-time-missed item had greater association with VL than did the 2-day recall, particularly for longer times (e.g., past month). By age group, significant associations with VL were found for caregiver reports in early adolescence, caregiver and youth reports in middle adolescence, and youth reports in late adolescence, suggesting that caregivers offer better reports of youth adherence during early adolescence, but by later adolescence, youth are better informants. Although design limitations preclude definitive conclusions about the reliability and validity of specific adherence items, this study suggests important issues related to age group, caregiver vs. youth informants of adherence, and recall periods for child adherence assessment that warrant further research.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Caregivers , HIV Infections/drug therapy , HIV Infections/psychology , Medication Adherence/statistics & numerical data , Adolescent , Child , Female , Humans , Interviews as Topic , Longitudinal Studies , Male , Medication Adherence/psychology , Multivariate Analysis , New York City , Parents , Reproducibility of Results , Socioeconomic Factors , Surveys and Questionnaires , Viral Load , Young Adult
11.
Cancer Discov ; 4(5): 606-19, 2014 May.
Article in English | MEDLINE | ID: mdl-24535670

ABSTRACT

Activating mutations in the EGF receptor (EGFR) are associated with clinical responsiveness to EGFR tyrosine kinase inhibitors (TKI), such as erlotinib and gefitinib. However, resistance eventually arises, often due to a second EGFR mutation, most commonly T790M. Through a genome-wide siRNA screen in a human lung cancer cell line and analyses of murine mutant EGFR-driven lung adenocarcinomas, we found that erlotinib resistance was associated with reduced expression of neurofibromin, the RAS GTPase-activating protein encoded by the NF1 gene. Erlotinib failed to fully inhibit RAS-ERK signaling when neurofibromin levels were reduced. Treatment of neurofibromin-deficient lung cancers with a MAP-ERK kinase (MEK) inhibitor restored sensitivity to erlotinib. Low levels of NF1 expression were associated with primary and acquired resistance of lung adenocarcinomas to EGFR TKIs in patients. These findings identify a subgroup of patients with EGFR-mutant lung adenocarcinoma who might benefit from combination therapy with EGFR and MEK inhibitors.


Subject(s)
Antineoplastic Agents/administration & dosage , Carcinoma, Non-Small-Cell Lung/drug therapy , Drug Resistance, Neoplasm , Erlotinib Hydrochloride/administration & dosage , Lung Neoplasms/drug therapy , Neurofibromin 1/genetics , Pyridones/administration & dosage , Pyrimidinones/administration & dosage , Animals , Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/genetics , Cell Line, Tumor , Erlotinib Hydrochloride/therapeutic use , Humans , Lung Neoplasms/genetics , MAP Kinase Signaling System , Mice , Neoplasms, Experimental , Neurofibromin 1/metabolism , Pyridones/therapeutic use , Pyrimidinones/therapeutic use
12.
J Sex Res ; 51(5): 599-604, 2014.
Article in English | MEDLINE | ID: mdl-24299282

ABSTRACT

Among young adults who use condoms, incomplete condom use (putting a condom on after beginning or taking a condom off before finishing sex) and condom failure (condom breaking or slipping off during sex) are common. Therefore, sexual behavior surveys that ask only if a condom was used are likely to underestimate the actual prevalence of unprotected sex. This study examined data from 135 sexually active perinatally HIV-infected (PHIV+) youth and perinatally exposed but uninfected (PHIV-) youth, ages 13 to 24. Participants were asked whether they used a condom on their first and their most recent occasion of vaginal sex. Youth who reported using a condom were asked a follow-up question about whether there was any time during that occasion when sex was not protected by a condom. This follow-up question identified additional participants--almost double the proportions who initially said they did not use a condom--who had unprotected sex. Incomplete condom use was similar among PHIV+ and PHIV-youth, boys and girls, Latinos and African Americans, and younger and older youth. These findings illustrate the importance of asking specifically about whether any unprotected behavior occurred from start to finish of sex to achieve more valid estimates of sexual risk behavior.


Subject(s)
Adolescent Behavior/psychology , Condoms/statistics & numerical data , HIV Infections/prevention & control , Infectious Disease Transmission, Vertical/statistics & numerical data , Unsafe Sex/statistics & numerical data , Adolescent , Adult , Female , HIV Infections/epidemiology , Humans , Male , New York City/epidemiology , Young Adult
13.
Clin Cancer Res ; 19(13): 3533-44, 2013 Jul 01.
Article in English | MEDLINE | ID: mdl-23674493

ABSTRACT

PURPOSE: Endometrioid endometrial cancers (EEC) frequently harbor coexisting mutations in phosphoinositide 3-kinase (PI3K) pathway genes, including PTEN, PIK3CA, PIK3R1, and KRAS. We sought to define the genetic determinants of PI3K pathway inhibitor response in EEC cells, and whether PTEN-mutant EEC cell lines rely on p110ß signaling for survival. EXPERIMENTAL DESIGN: Twenty-four human EEC cell lines were characterized for their mutation profile and activation state of PI3K and mitogen-activated protein kinase (MAPK) signaling pathway proteins. Cells were treated with pan-class I PI3K, p110α, and p110ß isoform-specific, allosteric mTOR, mTOR kinase, dual PI3K/mTOR, mitogen-activated protein/extracellular signal-regulated kinase (MEK), and RAF inhibitors. RNA interference (RNAi) was used to assess effects of KRAS silencing in EEC cells. RESULTS: EEC cell lines harboring PIK3CA and PTEN mutations were selectively sensitive to the pan-class I PI3K inhibitor GDC-0941 and allosteric mTOR inhibitor temsirolimus, respectively. Subsets of EEC cells with concurrent PIK3CA and/or PTEN and KRAS mutations were sensitive to PI3K pathway inhibition, and only 2 of 6 KRAS-mutant cell lines showed response to MEK inhibition. KRAS RNAi silencing did not induce apoptosis in KRAS-mutant EEC cells. PTEN-mutant EEC cell lines were resistant to the p110ß inhibitors GSK2636771 and AZD6482, and only in combination with the p110α selective inhibitor A66 was a decrease in cell viability observed. CONCLUSIONS: Targeted pan-PI3K and mTOR inhibition in EEC cells may be most effective in PIK3CA- and PTEN-mutant tumors, respectively, even in a subset of EECs concurrently harboring KRAS mutations. Inhibition of p110ß alone may not be sufficient to sensitize PTEN-mutant EEC cells and combination with other targeted agents may be required.


Subject(s)
Endometrial Neoplasms/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Apoptosis/drug effects , Apoptosis/genetics , Cell Line, Tumor , Class Ia Phosphatidylinositol 3-Kinase/genetics , Class Ia Phosphatidylinositol 3-Kinase/metabolism , Endometrial Neoplasms/genetics , Female , Gene Silencing , Humans , Indazoles/pharmacology , Mutation , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Phosphatidylinositol 3-Kinases/genetics , Phosphoinositide-3 Kinase Inhibitors , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins p21(ras) , Signal Transduction/drug effects , Sulfonamides/pharmacology , ras Proteins/genetics , ras Proteins/metabolism
14.
AIDS Behav ; 17(6): 1979-91, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23468079

ABSTRACT

Effective medical treatment for HIV/AIDS requires patients' optimal adherence to antiretroviral therapy (ART). In resource-constrained settings, lack of adequate standardized counseling for patients on ART remains a significant barrier to adherence. Masivukeni ("Let's Wake Up" in Xhosa) is an innovative multimedia-based intervention designed to help people living with HIV in resource-limited settings achieve and maintain high levels of ART adherence. Adapted from a couples-based intervention tested in the United States (US), Masivukeni was developed through community-based participatory research with US and South African partners and informed by Ewart's Social Action Theory. Innovative computer-based multimedia strategies were used to translate a labor- and training-intensive intervention into one that could be readily and widely used by lay counselors with relatively little training with low-literacy patients. In this paper, we describe the foundations of this new intervention, the process of its development, and the evidence of its high acceptability and feasibility.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Medication Adherence , Multimedia , Patient Education as Topic/methods , Adult , Counseling/methods , Female , HIV Infections/psychology , Health Knowledge, Attitudes, Practice , Humans , Male , Medication Adherence/psychology , Program Evaluation , Self Disclosure , Social Support , South Africa
15.
Cell Res ; 22(8): 1227-45, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22613949

ABSTRACT

Oncogenic mutations in RAS genes are very common in human cancer, resulting in cells with well-characterized selective advantages, but also less well-understood vulnerabilities. We have carried out a large-scale loss-of-function screen to identify genes that are required by KRAS-transformed colon cancer cells, but not by derivatives lacking this oncogene. Top-scoring genes were then tested in a larger panel of KRAS mutant and wild-type cancer cells. Cancer cells expressing oncogenic KRAS were found to be highly dependent on the transcription factor GATA2 and the DNA replication initiation regulator CDC6. Extending this analysis using a collection of drugs with known targets, we found that cancer cells with mutant KRAS showed selective addiction to proteasome function, as well as synthetic lethality with topoisomerase inhibition. Combination targeting of these functions caused improved killing of KRAS mutant cells relative to wild-type cells. These observations suggest novel targets and new ways of combining existing therapies for optimal effect in RAS mutant cancers, which are traditionally seen as being highly refractory to therapy.


Subject(s)
Antineoplastic Agents/pharmacology , Colonic Neoplasms/genetics , Proto-Oncogene Proteins/metabolism , ras Proteins/metabolism , Alleles , Apoptosis , Boronic Acids/pharmacology , Bortezomib , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Cell Survival , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , DNA Topoisomerases, Type I/metabolism , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacology , GATA2 Transcription Factor/genetics , GATA2 Transcription Factor/metabolism , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , Humans , Mutation , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Proteasome Endopeptidase Complex/genetics , Proteasome Endopeptidase Complex/metabolism , Proteasome Inhibitors/pharmacology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins p21(ras) , Pyrazines/pharmacology , RNA Interference , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Topoisomerase I Inhibitors/pharmacology , Topotecan/pharmacology , Transcriptional Activation , ras Proteins/genetics , Gemcitabine
16.
Mol Cell Biol ; 30(2): 481-95, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19917724

ABSTRACT

The target of rapamycin (TOR) complex 1 (TORC1) signaling pathway is a critical regulator of translation and cell growth. To identify novel components of this pathway, we performed a kinome-wide RNA interference (RNAi) screen in Drosophila melanogaster S2 cells. RNAi targeting components of the p38 stress-activated kinase cascade prevented the cell size increase elicited by depletion of the TOR negative regulator TSC2. In mammalian and Drosophila tissue culture, as well as in Drosophila ovaries ex vivo, p38-activating stresses, such as H(2)O(2) and anisomycin, were able to activate TORC1. This stress-induced TORC1 activation could be blocked by RNAi against mitogen-activated protein kinase kinase 3 and 6 (MKK3/6) or by the overexpression of dominant negative Rags. Interestingly, p38 was also required for the activation of TORC1 in response to amino acids and growth factors. Genetic ablation either of p38b or licorne, its upstream kinase, resulted in small flies consisting of small cells. Mutants with mutations in licorne or p38b are nutrition sensitive; low-nutrient food accentuates the small-organism phenotypes, as well as the partial lethality of the p38b null allele. These data suggest that p38 is an important positive regulator of TORC1 in both mammalian and Drosophila systems in response to certain stresses and growth factors.


Subject(s)
Cell Cycle Proteins/metabolism , Drosophila Proteins/metabolism , Transcription Factors/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Alleles , Animals , Antibiotics, Antineoplastic/pharmacology , Cell Cycle Proteins/genetics , Cell Line , Cell Size/drug effects , Drosophila Proteins/genetics , Drosophila melanogaster/cytology , Drosophila melanogaster/enzymology , Drosophila melanogaster/genetics , Estrogen Antagonists/pharmacology , Female , Gene Expression Regulation, Developmental/drug effects , Gene Expression Regulation, Developmental/genetics , Gene Expression Regulation, Developmental/physiology , Humans , Hydrogen Peroxide/pharmacology , Larva/genetics , Larva/metabolism , Male , Mutation , Ovary/cytology , Ovary/enzymology , Oxidants/pharmacology , Phosphorylation/drug effects , Phosphorylation/physiology , RNA Interference/physiology , Signal Transduction/drug effects , Signal Transduction/physiology , Sirolimus/pharmacology , Tamoxifen/pharmacology , Transcription Factors/drug effects , Transcription Factors/genetics , p38 Mitogen-Activated Protein Kinases/drug effects , p38 Mitogen-Activated Protein Kinases/genetics
17.
Cell ; 129(5): 957-68, 2007 Jun 01.
Article in English | MEDLINE | ID: mdl-17540175

ABSTRACT

Ras proteins signal through direct interaction with a number of effector enzymes, including type I phosphoinositide (PI) 3-kinases. Although the ability of Ras to control PI 3-kinase has been well established in manipulated cell culture models, evidence for a role of the interaction of endogenous Ras with PI 3-kinase in normal and malignant cell growth in vivo has been lacking. Here we generate mice with mutations in the Pi3kca gene encoding the catalytic p110alpha isoform that block its interaction with Ras. Cells from these mice show proliferative defects and selective disruption of signaling from growth factors to PI 3-kinase. The mice display defective development of the lymphatic vasculature, resulting in perinatal appearance of chylous ascites. Most importantly, they are highly resistant to endogenous Ras oncogene-induced tumorigenesis. The interaction of Ras with p110alpha is thus required in vivo for certain normal growth factor signaling and for Ras-driven tumor formation.


Subject(s)
Cell Transformation, Neoplastic/metabolism , Phosphatidylinositol 3-Kinases/metabolism , ras Proteins/metabolism , Amino Acid Sequence , Animals , Cattle , Cell Proliferation , Class I Phosphatidylinositol 3-Kinases , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Fibroblasts/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Lymphatic Abnormalities/genetics , Lymphatic Abnormalities/metabolism , Mice , Mice, Inbred C57BL , Molecular Sequence Data , Phosphatidylinositol 3-Kinases/genetics , Point Mutation , Protein Binding , Protein Structure, Tertiary , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Sequence Alignment , Signal Transduction
18.
Cancer Cell ; 11(6): 498-512, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17560332

ABSTRACT

Cytotoxic drug resistance is a major cause of cancer treatment failure. We report an RNA interference screen to identify genes influencing sensitivity of different cancer cell types to chemotherapeutic agents. A set of genes whose targeting leads to resistance to paclitaxel is identified, many of which are involved in the spindle assembly checkpoint. Silencing these genes attenuates paclitaxel-induced mitotic arrest and induces polyploidy in the absence of drug. We also identify a ceramide transport protein, COL4A3BP or CERT, whose downregulation sensitizes cancer cells to multiple cytotoxic agents, potentiating endoplasmic reticulum stress. COL4A3BP expression is increased in drug-resistant cell lines and in residual tumor following paclitaxel treatment of ovarian cancer, suggesting that it could be a target for chemotherapy-resistant cancers.


Subject(s)
Ceramides/metabolism , Drug Resistance, Neoplasm , Mitosis , Paclitaxel/pharmacology , Protein Serine-Threonine Kinases/physiology , Cell Line, Tumor , Cell Survival/drug effects , Chromosomal Instability , Down-Regulation , Drug Resistance, Multiple/genetics , Female , Humans , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/metabolism , Paclitaxel/therapeutic use , Polyploidy , Protein Kinases/metabolism , RNA, Small Interfering/pharmacology
19.
J Youth Adolesc ; 36(3): 265-78, 2007 Apr.
Article in English | MEDLINE | ID: mdl-27519026

ABSTRACT

HIV-negative, inner-city adolescents with HIV-infected parents are considered to be at high risk for acquiring HIV themselves. Using a modified theory of health behavior, this study examined the effects of maternal HIV infection and psychosocial variables on the onset of sexual and drug risk behavior in 144 HIV-negative adolescents with and without HIV-positive mothers. Adolescents and their mothers were interviewed when the youths were 10-14 years old and again when they were 13-19 years old. By follow-up, 42% of youths reported the onset of vaginal sex (vs 5% at baseline). Marijuana and alcohol use increased from 6 and 38%, respectively, at baseline to 25 and 60% at follow-up. Among those reporting risk behaviors, 40--50% reported onset prior to 14 years. Youth and family psychosocial variables, but not maternal HIV status, were associated with risk behaviour outcomes.

20.
J Acquir Immune Defic Syndr ; 43 Suppl 1: S69-78, 2006 Dec 01.
Article in English | MEDLINE | ID: mdl-17133206

ABSTRACT

There is a dearth of evidence on the relative efficacy of intervention modalities to improve and maintain patient adherence to antiretroviral medications. Although empiric findings from research on HIV/AIDS, other diseases, and chronic medical conditions consistently demonstrate that social support plays an important role in facilitating adherence, few HIV/AIDS interventions have directly targeted this factor. Ewart's social action theory emphasizes the role of social relationships in behavior change and provides a comprehensive and useful guide to the development of interventions for adherence. We describe the development, content, and testing of SMART Couples, an effective antiretroviral adherence intervention that is grounded in social action theory and designed to enhance social support for ART adherence. Finally, we discuss some of the challenges of translating findings from the randomized clinical trial of this intervention into clinical practice and offer recommendations for integration of lessons learned into ongoing clinical care.


Subject(s)
Anti-HIV Agents/administration & dosage , Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Patient Compliance , Sexual Partners , Health Knowledge, Attitudes, Practice , Humans
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