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1.
Cancer Discov ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38552003

RESUMO

Resistance to poly (ADP-ribose) polymerase inhibitors (PARPi) limits the therapeutic efficacy of PARP inhibition in treating breast cancer susceptibility gene 1 (BRCA1)-deficient cancers. Here we reveal that BRCA1 has a dual role in regulating ferroptosis. BRCA1 promotes the transcription of voltage-dependent anion channel 3 (VDAC3) and glutathione peroxidase 4 (GPX4); consequently, BRCA1 deficiency promotes cellular resistance to erastin-induced ferroptosis but sensitizes cancer cells to ferroptosis induced by GPX4 inhibitors (GPX4i). In addition, nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy and defective GPX4 induction unleash potent ferroptosis in BRCA1-deficient cancer cells upon PARPi and GPX4i co-treatment. Finally, we show that xenograft tumors derived from BRCA1-mutant breast cancer patients with PARPi resistance exhibit decreased GPX4 expression and high sensitivity to PARP and GPX4 co-inhibition. Our results show that BRCA1 deficiency induces a ferroptosis vulnerability to PARP and GPX4 co-inhibition and inform a therapeutic strategy for overcoming PARPi resistance in BRCA1-deficient cancers.

2.
Eur J Oncol Nurs ; 68: 102469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38039708

RESUMO

PURPOSE: Cancer-related fatigue (CRF) is a highly prevalent and debilitating symptom reported by breast cancer survivors (BCS). CRF has been associated with the co-occurrence of anxiety, depression, poor sleep quality, cognitive impairment, which are collectively termed as psychoneurophysiological (PNP) symptoms. CRF and these PNP symptoms are often reported during and after treatment with long-lasting distress. It is unclear how CRF and these PNP symptoms influence each other. This study aimed to explore predictive factors (i.e., PNP symptoms and social-demographic factors) of CRF, and test exploratory path models of the relationships of CRF with PNP symptoms (depression, anxiety, sleep disturbance, pain, and cognitive function) in BCS. METHODS: This paper is part of a larger descriptive, correlational, and cross-sectional study. Validated and reliable instruments assessed CRF, depression, anxiety, sleep disturbance, pain, and cognitive function. Descriptive statistics, Pearson correlation, multiple linear regression models, and path analysis were employed. RESULTS: Patients (N = 373) who reported less bodily pain had worst CRF (r = -0.45, p < .01). Significant predictors of CRF included depression, sleep disorder, bodily pain, perceived cognitive ability, and dispositional (state) optimism. Depression alone accounted for 31% of the variance in CRF. An integrative path model with bodily pain, neuropathic pain, CRF, and depression showed a good fit across different indices (CFI = 0.993, RMSEA = 0.047, 90% CI 0-0.12, SRMR = 0.027). CONCLUSIONS: This study identified significant predictors of CRF and revealed a good fit mediation model with significant pathways for CRF, suggesting that a common etiology may underpin the co-occurrence of CRF with PNP symptoms (pain and depression). However, further investigation with longitudinal design is necessary to explore the causal relationships of these symptoms. Evidence-based strategies/interventions are needed to reduce or eliminate the burden of these symptoms on the lives of BCS.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Neuralgia , Humanos , Feminino , Neoplasias da Mama/complicações , Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Estudos Transversais , Fadiga/diagnóstico , Fadiga/epidemiologia , Fadiga/etiologia , Depressão/epidemiologia , Depressão/etiologia , Qualidade de Vida
4.
Am J Cancer Res ; 13(4): 1209-1239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168336

RESUMO

Nuclear epidermal growth factor receptor (EGFR) has been shown to be correlated with drug resistance and a poor prognosis in patients with cancer. Previously, we have identified a tripartite nuclear localization signal (NLS) within EGFR. To comprehensively determine the functions and underlying mechanism of nuclear EGFR and its clinical implications, we aimed to explore the nuclear export signal (NES) sequence of EGFR that is responsible for interacting with the exportins. We combined in silico prediction with site-directed mutagenesis approaches and identified a putative NES motif of EGFR, which is located in amino acid residues 736-749. Mutation at leucine 747 (L747) in the EGFR NES led to increased nuclear accumulation of the protein via a less efficient release of the exportin CRM1. Interestingly, L747 with serine (L747S) and with proline (L747P) mutations were found in both tyrosine kinase inhibitor (TKI)-treated and -naïve patients with lung cancer who had acquired or de novo TKI resistance and a poor outcome. Reconstituted expression of the single NES mutant EGFRL747P or EGFRL747S, but not the dual mutant along with the internalization-defective or NLS mutation, in lung cancer cells promoted malignant phenotypes, including cell migration, invasiveness, TKI resistance, and tumor initiation, supporting an oncogenic role of nuclear EGFR. Intriguingly, cells with germline expression of the NES L747 mutant developed into B cell lymphoma. Mechanistically, nuclear EGFR signaling is required for sustaining nuclear activated STAT3, but not for Erk. These findings suggest that EGFR functions are compartmentalized and that nuclear EGFR signaling plays a crucial role in tumor malignant phenotypes, leading to tumorigenesis in human cancer.

5.
Nat Cancer ; 3(10): 1211-1227, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36253486

RESUMO

Poly(ADP-ribose) polymerase (PARP) inhibitors have demonstrated promising clinical activity in multiple cancers. However, resistance to PARP inhibitors remains a substantial clinical challenge. In the present study, we report that anaplastic lymphoma kinase (ALK) directly phosphorylates CDK9 at tyrosine-19 to promote homologous recombination (HR) repair and PARP inhibitor resistance. Phospho-CDK9-Tyr19 increases its kinase activity and nuclear localization to stabilize positive transcriptional elongation factor b and activate polymerase II-dependent transcription of HR-repair genes. Conversely, ALK inhibition increases ubiquitination and degradation of CDK9 by Skp2, an E3 ligase. Notably, combination of US Food and Drug Administration-approved ALK and PARP inhibitors markedly reduce tumor growth and improve survival of mice in PARP inhibitor-/platinum-resistant tumor xenograft models. Using human tumor biospecimens, we further demonstrate that phosphorylated ALK (p-ALK) expression is associated with resistance to PARP inhibitors and positively correlated with p-Tyr19-CDK9 expression. Together, our findings support a biomarker-driven, combinatorial treatment strategy involving ALK and PARP inhibitors to induce synthetic lethality in PARP inhibitor-/platinum-resistant tumors with high p-ALK-p-Tyr19-CDK9 expression.


Assuntos
Quinase do Linfoma Anaplásico , Antineoplásicos , Neoplasias da Mama , Quinase 9 Dependente de Ciclina , Animais , Feminino , Humanos , Camundongos , Quinase do Linfoma Anaplásico/metabolismo , Antineoplásicos/farmacologia , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Quinase 9 Dependente de Ciclina/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Fator B de Elongação Transcricional Positiva , Tirosina/química , Tirosina/metabolismo , Ubiquitina-Proteína Ligases/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Estados Unidos
6.
Am J Cancer Res ; 12(5): 2363-2375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693073

RESUMO

Immunotherapies that block PD-L1/PD-1 immune checkpoint proteins represent a landmark breakthrough in cancer treatment. Although the role of PD-L1 in suppressing T cell activity has been extensively studied, its cancer cell-intrinsic functions are not well understood. Herein, we demonstrated that PD-L1 is important for the repair of DNA damage in cancer cells. Mechanically, depletion of PD-L1 led to the downregulation of the critical molecules involved in the homologous recombination (HR) repair pathway, such as ATM and BRCA1, but did not obviously affect the non-homologous end joining (NHEJ) pathway. Notably, PD-L1 silence sensitized cancer cells to chemotherapy agents and the inhibitor of DNA-PK, which is an important kinase for NHEJ. Furthermore, PD-L1 depletion potentiated DNA damage-induced cGAS-STING pathway and induction of IFNß. The regulation of DNA repair and cGAS-STING pathway by PD-L1 represents its connection with innate immunity that can be exploited to enhance the efficacy of existing immunotherapy. Our findings thus expand the focus of PD-L1 from tumor antigen-specific CD8+ T cells to innate immunity, and support targeting tumor-intrinsic PD-L1 combined with DNA-PK inhibition for tumor eradication, through promoting synthetic lethality and innate immune response.

7.
Transl Behav Med ; 12(6): 752-760, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35661225

RESUMO

Underserved populations, including those from racial and ethnic groups and with low socioeconomic status, often lack access to mobile apps aimed at reducing health risk factors. This study evaluated the feasibility, acceptability, and preliminary effectiveness of the mobile app, My Wellness Coach (MWC), designed to promote behavior change in seven core areas of integrative health among underserved populations. Patients and staff were recruited from clinic and other settings. Some participants used MWC in a weekly group setting (n = 5); others on their own with support from a coordinator (n = 36). Health outcomes were assessed at baseline and 3 months. Mobile app ratings were collected at 5 weeks and 3 months. Goal setting data were analyzed at 3 months. Most participants (76%) set at least one goal, 71% created action steps for goals, and 29% completed a goal. Patients in the group setting had the highest rate of goal completion (60%) compared to patients (20%) and staff (27%) using the app on their own. Significant (p < .05) changes in pre- and post-test scores were documented for overall wellbeing, global physical health, BMI, vigorous physical activity, and eHealth literacy. Most participants (75%-91%) gave MWC high ratings for impact on behavior change, help seeking, intent to change, attitudes, knowledge, and awareness. This study documented preliminary evidence of the potential benefits of MWC among underserved communities. Future evaluations of Spanish and Android versions and comparisons between group and individual administration will inform implementation strategies for scaling MWC-based interventions to reach underserved communities nationally.


Many underserved populations, including those from diverse racial and ethnic groups and with low income, do not have access to mobile apps to improve health. This study examined whether using the My Wellness Coach (MWC) app was feasible, acceptable, and effective. MWC was designed to promote behavior change in integrative health (Movement, Nutrition, Spirituality, Resilience, Relationships, Sleep, and Environment) among underserved populations. Five participants used MWC in a group setting and 36 participants used MWC on their own with assistance from a coordinator. Participants completed surveys at the beginning of the study and 3 months later. Most participants (76%) set at least one health goal, 71% created action steps for goals, and 29% completed a goal. Participants who used MWC with the weekly group had the highest rate of goal completion (60%). Participants reported significant changes in wellbeing, physical health, body mass index, physical activity, and ability to find and understand electronic health information. Most participants (75%­91%) gave MWC positive ratings. This study provided evidence of the potential benefits of MWC among underserved communities. Future studies with Spanish and Android versions and comparisons between group and individual administration will inform strategies for expanding the reach of MWC-based interventions to underserved communities.


Assuntos
Medicina Integrativa , Aplicativos Móveis , Telemedicina , Humanos , Hispânico ou Latino , Populações Vulneráveis , Saúde Holística , Determinantes Sociais da Saúde , Grupos Minoritários , Baixo Nível Socioeconômico , Estados Unidos
8.
Am J Cancer Res ; 12(1): 337-354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35141022

RESUMO

Acquired resistance and clonal heterogeneity are critical challenges in cancer treatment, and the lack of effective computational tools hampers the discovery of new treatments to overcome resistance. Using high-throughput transcriptomic databases of compound perturbation profiles, we have developed a bioinformatic strategy for identifying candidate drugs to overcome resistance with combinatorial therapy. We devised this strategy during an investigation into the acquired resistance against PARP inhibitors (PARPi) in a triple-negative inflammatory breast cancer cell line. In this study, we derived multiple PARPi-resistant clones and characterized their transcriptomic adaptations compared to the parental clone. The transcriptomes of the resistant clones showed substantial heterogeneity, highlighting the importance of characterizing multiple clones from the same tumour. Surprisingly, we found that these transcriptomic changes may not actually confer PARPi resistance, but they may nevertheless induce a shared secondary vulnerability. By modeling our data in relation to transcriptomic perturbation profiles of compounds, we uncovered deficiencies in Ras signaling that resulted from transcriptional adaptation to long-term PARPi treatment across multiple resistant clones. Due to these induced deficiencies, we predicted that the resistant clones would be sensitive to pharmacological reinforcement of PARPi-induced transcriptional adaptation. We then experimentally validated this predicted vulnerability that is shared by multiple resistant clones. Our results thus provide a promising paradigm for integrating transcriptomic data with compound perturbation profiles in order to identify drugs that can exploit an induced vulnerability and overcome therapeutic resistance, thus providing another strategy towards precision oncology.

9.
Nurs Res ; 70(6): 475-480, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34380980

RESUMO

BACKGROUND: Cancer-related fatigue (CRF) is a highly prevalent, debilitating, and persistent symptom experienced by patients receiving cancer treatments. Up to 71% of men with prostate cancer receiving radiation therapy experience acute and persistent CRF. There is neither an effective therapy nor a diagnostic biomarker for CRF. This pilot study aimed to discover potential biomarkers associated with chronic CRF in men with prostate cancer receiving radiation therapy. METHODS: We used a longitudinal repeated-measures research design. Twenty men with prostate cancer undergoing radiation therapy completed all study visits. CRF was evaluated by a well-established and validated questionnaire, the Patient-Reported Outcomes Measurement Information System for Fatigue (PROMIS-F) Short Form. In addition, peripheral blood mononuclear cells were harvested to quantify ribonucleic acid (RNA) gene expression of mitochondria-related genes. Data were collected before, during, on completion, and 24 months postradiation therapy and analyzed using paired t-tests and repeated-measures analysis of variance. RESULTS: The mean of the PROMIS-F T score was significantly increased over time in patients with prostate cancer, remaining elevated at 24 months postradiation therapy compared to baseline. A significant downregulated BC1 ubiquinol-cytochrome c reductase synthesis-like (BCS1L) was observed over time during radiation therapy and at 24 months postradiation therapy. An increased PROMIS-F score was trended with downregulated BCS1L in patients 24 months after completing radiation therapy. DISCUSSION: This is the first evidence to describe altered messenger RNA for BCS1L in chronic CRF using the PROMIS-F measure with men receiving radiation therapy for prostate cancer. CONCLUSION: Our results suggest that peripheral blood mononuclear cell messenger RNA for BCS1L is a potential biomarker and therapeutic target for radiation therapy-induced chronic CRF in this clinical population.


Assuntos
Biomarcadores/sangue , Metabolismo Energético , Fadiga/diagnóstico , Fadiga/etiologia , Leucócitos Mononucleares , Neoplasias da Próstata/complicações , Neoplasias da Próstata/radioterapia , Idoso , Doença Crônica , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Inquéritos e Questionários
10.
FEBS J ; 288(9): 2884-2887, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33570247

RESUMO

The efficacy of the combination of a PARP inhibitor (PARPi) and an EZH2 inhibitor has been investigated in breast cancer cells with either BRCA1 mutation or BRCA2 mutation. However, earlier studies focused on the efficacy of this combination against BRCA-mutated but not BRCA-proficient breast cancer. Yang et al. observed that PARP1 depletion combined with EZH2 depletion via PRC2 depletion did not affect the growth of BRCA1/2 wild-type breast cancer cells in vitro. Moreover, Yang et al. reported that this combination stimulated synthetic viability of BRCA1/2-proficient breast cancer cells in vivo by regulating the tumor microenvironment to induce angiogenesis and differentiation of M2-type macrophages. The findings of Yang et al. provided evidence that both in vitro and animal models should be employed in the studies of PARPi combination therapies in order to involve the alteration of the tumor microenvironment in these investigations. These studies of PARP inhibition combined with EZH2 inhibition in breast cancer showed that this combination may benefit breast cancer patients carrying BRCA1-mutated tumor, but the combination may also enhance recurrence of BRCA2-mutated tumor and may even promote BRCA-proficient cancer cell survival. Therefore, BRCA1 mutation status should be used to select breast cancer patients for PARPi and EZH2 inhibitor combination treatment in clinical trials in the future.


Assuntos
Neoplasias da Mama , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Humanos , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Microambiente Tumoral
11.
Am J Cancer Res ; 11(1): 236-250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33520371

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer that lack effective therapeutic strategies. The response rate of PDAC for treatment with gemcitabine, a current first-line chemotherapeutic for this tumor, is lower than 20%. Identifying key targetable molecules that mediate gemcitabine resistance and developing novel strategies for precision PDAC medicine are urgently needed. Most PDACs have either intratumoral hypoxia or high reactive oxygen species (ROS) production; cytotoxic chemotherapy can elevate ROS production in PDACs. Although excessive ROS production leads to oxidative damage of macromolecules such as DNA, pancreatic cancer cells can survive high DNA damage stress levels. Therefore, identifying molecular mechanisms of overcoming ROS-induced stress in pancreatic cancer cells is important for developing novel therapeutic strategies. ROS-induced DNA damage is predominantly repaired via poly (ADP-ribose) polymerase 1 (PARP1)-mediated DNA repair mechanisms. A recent clinical trial reported that PARP inhibitors are effective in treating pancreatic patients carrying BRCA mutations. However, only less than 10% of pancreatic cancer patients bearing BRCA mutated tumors. Activation of the receptor tyrosine kinase c-MET positively correlates with poor prognosis for PDAC, and our previous study showed that nuclear c-MET can phosphorylate PARP1 at tyrosine 907 under ROS stimulation to promote DNA repair. As described herein, we proposed to expand PARP inhibitor-targeted therapy to more pancreatic cancer patients regardless of BRCA mutation status by combining olaparib, a PARP inhibitor, with c-MET inhibitors as we demonstrated in our previous studies in breast cancer. In this prospective study, we found that ROS-inducing chemotherapeutic drugs such as gemcitabine and doxorubicin stimulated nuclear accumulation of c-MET in BxPC-3 and L3.6pl pancreatic cancer cells. We further showed that combining a c-MET inhibitor with gemcitabine or a PARP inhibitor induced more DNA damage than monotherapy did. Moreover, we demonstrated the synergistic antitumor effects of c-MET inhibitors combined with a PARP inhibitor or gemcitabine in eliminating pancreatic cancer cells. These data suggested that accumulation of ROS in pancreatic cancer cells promotes nuclear localization of c-MET, resulting in resistance to both chemotherapy and PARP inhibitors. Our findings suggest that combining c-MET inhibitors with PARP inhibitors or gemcitabine is a novel, rational therapeutic strategy for advanced pancreatic cancer.

12.
Explore (NY) ; 17(6): 505-512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32229083

RESUMO

BACKGROUND: Although there is mounting clinical and cost-effectiveness evidence supporting integrative healthcare (IH), a significant knowledge gap hinders widespread adoption by health professionals. INTERVENTION: Foundations in Integrative Health (FIH), a 32-h online competency-based interprofessional course to address this knowledge gap. METHODS: The course was pilot-tested by an interprofessional sample of providers in various clinical settings as professional and staff development. OUTCOME MEASURES: Prior to and following the course, participants completed an IH knowledge test, an IH self-efficacy self-assessment, and validated measures of burnout, wellness behaviors, and attitudes toward IH, interprofessional teams, and patient involvement. Evaluation surveys were administered following each unit and the course. RESULTS: Thirty-one percent of the participants (n = 214/690) completed the course. Pre/post course improvements were found in IH knowledge, IH self-efficacy, attitudes towards IH and interprofessional teams, and several wellness behaviors. The course was positively evaluated with 81% of the participants indicating interest in applying IH principles in their practice and 92% reported that the course enhanced their clinical experience. CONCLUSION: This study demonstrates the outcomes of a multi-site, online IH curriculum offered to a diverse group of health professionals in various clinical settings. This course may allow clinical settings to offer an interprofessional, IH curriculum even with limited on-site faculty expertise.


Assuntos
Currículo , Pessoal de Saúde , Atitude do Pessoal de Saúde , Humanos , Relações Interprofissionais , Inquéritos e Questionários
13.
Adv Cancer Res ; 147: 59-107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32593407

RESUMO

Signaling functions of plasma membrane-localized receptor tyrosine kinases (RTKs) have been extensively studied after they were first described in the mid-1980s. Plasma membrane RTKs are activated by extracellular ligands and cellular stress stimuli, and regulate cellular responses by activating the downstream effector proteins to initiate a wide range of signaling cascades in the cells. However, increasing evidence indicates that RTKs can also be transported into the intracellular compartments where they phosphorylate traditional effector proteins and non-canonical substrate proteins. In general, internalization that retains the RTK's transmembrane domain begins with endocytosis, and endosomal RTK remains active before being recycled or degraded. Further RTK retrograde transport from endosome-Golgi-ER to the nucleus is primarily dependent on membranes vesicles and relies on the interaction with the COP-I vesicle complex, Sec61 translocon complex, and importin. Internalized RTKs have non-canonical substrates that include transcriptional co-factors and DNA damage response proteins, and many nuclear RTKs harbor oncogenic properties and can enhance cancer progression. Indeed, nuclear-localized RTKs have been shown to positively correlate with cancer recurrence, therapeutic resistance, and poor prognosis of cancer patients. Therefore, understanding the functions of nuclear RTKs and the mechanisms of nuclear RTK transport will further improve our knowledge to evaluate the potential of targeting nuclear RTKs or the proteins involved in their transport as new cancer therapeutic strategies.


Assuntos
Núcleo Celular/enzimologia , Neoplasias/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Animais , Endocitose , Humanos , Neoplasias/enzimologia , Neoplasias/patologia , Fosforilação , Transporte Proteico , Transdução de Sinais
14.
Am J Cancer Res ; 10(2): 564-571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195027

RESUMO

Non-small cell lung cancer (NSCLC) patients with c-MET dysregulation may benefit from c-MET inhibitors therapy as inhibition of c-MET activity has emerged as a therapeutic approach against this disease. Although several c-MET inhibitors have been evaluated in multiple clinical trials in lung cancer, their benefits so far have been modest. Thus, furthering our understanding of the mechanisms contributing to the lack of success of c-MET inhibitors in clinical trials is essential toward the development of rational and effective combination strategies. Here we show that exposure of NCSLC cell lines to c-MET inhibitor tivantinib increases their expression of PD-L1, which in turn causes cells to become more resistant to T-cell killing. Mechanistically, inhibition of c-MET suppresses p-GSK3ß, leading to the stabilization of PD-L1 similar to that observed in liver cancer cells. Collectively, our findings suggest a potential crosstalk between c-MET inhibition and immune escape and provide a rationale for the combination therapy of c-MET inhibitors and immune checkpoint blockade in NSCLC.

15.
Am J Cancer Res ; 10(2): 648-661, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195033

RESUMO

The limited treatment options and therapeutic failure due to acquired resistance for patients with triple-negative breast cancer (TNBC) represent a significant challenge. Inhibitors against poly (ADP-ribose) polymerase (PARP), olaparib and talazoparib, were recently approved for the treatment of metastatic breast cancer (including TNBC) in patients with germline BRCA1/2 mutations. Despite impressive response rates of ~60%, the prolongation in median progression-free survival with a PARPi is modest, suggesting the emergence of resistance. Several studies have reported that receptor tyrosine kinases (RTKs), such as c-MET (also known as hepatocyte growth factor receptor), are involved in resistance to various anti-neoplastic agents, including PARPi. However, the mechanism by which c-MET contributes to acquired resistance to PARPi in TNBC is not fully understood. In this study, we show that hyperactivated c-Met is detected in TNBC cells with acquired resistance to PARPi, and the combination of talazoparib and crizotinib (a multi-kinase inhibitor that inhibits c-MET) synergistically inhibits proliferation in these cells. Unexpectedly, depleting c-MET had limited effect on talazoparib sensitivity in PARPi-resistant cells. Interestingly, we found evidence of epidermal growth factor receptor (EGFR) hyperactivation and interaction of EGFR/c-Met in these cells. Notably, combining EGFR and PARP inhibitors resulted in greater inhibition of proliferation in c-MET-depleted TNBC cells, and combined c-MET and EGFR inhibition increased sensitivity to talazoparib in TNBC cells with acquired resistance to PARPi. Our findings suggest that combined inhibition of c-MET and EGFR could potentially re-sensitize TNBC to the cytotoxic effects of PARPi.

16.
Fam Med ; 52(3): 189-197, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32027377

RESUMO

BACKGROUND AND OBJECTIVES: Opioid misuse is at an all-time crisis level, and nationally enhanced resident and clinician education on chronic pain management is in demand. To date, broad-reaching, scalable, integrative pain management educational interventions have not been evaluated for effectiveness on learner knowledge or attitudes toward chronic pain management. METHODS: An 11-hour integrative pain management (IPM) online course was evaluated for effect on resident and faculty attitudes toward and knowledge about chronic pain. Participants were recruited from family medicine residencies participating in the integrative medicine in residency program. Twenty-two residencies participated, with 11 receiving the course and 11 serving as a control group. Evaluation included pre/post medical knowledge and validated measures of attitude toward pain patients, self-efficacy for nondrug therapies, burnout, and compassion. RESULTS: Forty-three participants (34.4%) completed the course. The intervention group (n=50), who received the course, improved significantly (P<.05) in medical knowledge, attitude toward pain patients, and self-efficacy to prescribe nondrug therapies while the control group (n=54) showed no improvement. There was no effect on burnout or compassion for either group. The course was positively evaluated, with 83%-94% rating the course content and delivery very high. All participants responded that they would incorporate course information into practice, and almost all thought what they learned in the course would improve patient care (98%). CONCLUSIONS: Our findings demonstrate the feasibility of an online IPM course as an effective and scalable intervention for residents and primary care providers in response to the current opioid crisis and need for better management of chronic pain. Future directions include testing scalability in formats that lead to improved completion rates, implementation in nonacademic settings, and evaluation of clinical outcomes such as decreased opioid prescribing.


Assuntos
Medicina de Família e Comunidade/educação , Medicina Integrativa/educação , Internato e Residência , Médicos , Humanos , Avaliação de Programas e Projetos de Saúde
17.
Explore (NY) ; 16(6): 392-400, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31980372

RESUMO

BACKGROUND: Although there is mounting clinical and cost-effectiveness evidence supporting integrative healthcare (IH), a significant knowledge gap hinders widespread adoption by primary care professionals. INTERVENTION: Based on IH competencies developed by an interprofessional team and a needs assessment, a 32-h online interprofessional IH course, Foundations in Integrative Health, was developed. Trainees learn to conduct an IH assessment and how patients are assessed and treated from the diverse professions in integrative primary care. METHODS: The course was pilot-tested with educational program trainees, faculty and clinical staff at graduate level primary care training programs (primary care residencies, nursing, pharmacy, public health, behavioral health, and licensed complementary and IH programs). OUTCOME MEASURES: Prior to and following the course, participants completed an IH knowledge test, an IH efficacy self-assessment, and validated measures of IH attitudes, interprofessional learning, provider empathy, patient involvement, resiliency, self-care, wellness behaviors, and wellbeing. Evaluation surveys were administered following each unit and the course. RESULTS: Almost one-half (n = 461/982, 47%) completed the course. Pre/post course improvements in IH knowledge, IH self-efficacy, IH attitudes, interprofessional learning, provider empathy, resiliency, self-care, several wellness behaviors, and wellbeing were observed. The course was positively evaluated with most (93%) indicating interest in applying IH principles and that the course enhanced their educational experience (92%). CONCLUSION: This study demonstrates the feasibility and effectiveness of a multi-site, online curriculum for introducing IH to a diverse group of primary care professionals. Primary care training programs have the ability to offer an interprofessional, IH curriculum with limited on-site faculty expertise.


Assuntos
Educação a Distância/métodos , Medicina Integrativa/educação , Atenção Primária à Saúde/métodos , Adulto , Currículo , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Centrada no Paciente/métodos , Projetos Piloto
18.
Nat Commun ; 10(1): 5654, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31827085

RESUMO

Poly(ADP-ribose)ylation (PARylation) by PAR polymerase 1 (PARP1) and PARylation removal by poly(ADP-ribose) glycohydrolase (PARG) critically regulate DNA damage responses; yet, conflicting reports obscure PARG biology and its impact on cancer cell resistance to PARP1 inhibitors. Here, we found that PARG expression is upregulated in many cancers. We employed chemical library screening to identify and optimize methylxanthine derivatives as selective bioavailable PARG inhibitors. Multiple crystal structures reveal how substituent positions on the methylxanthine core dictate binding modes and inducible-complementarity with a PARG-specific tyrosine clasp and arginine switch, supporting inhibitor specificity and a competitive inhibition mechanism. Cell-based assays show selective PARG inhibition and PARP1 hyperPARylation. Moreover, our PARG inhibitor sensitizes cells to radiation-induced DNA damage, suppresses replication fork progression and impedes cancer cell survival. In PARP inhibitor-resistant A172 glioblastoma cells, our PARG inhibitor shows comparable killing to Nedaplatin, providing further proof-of-concept that selectively inhibiting PARG can impair cancer cell survival.


Assuntos
Replicação do DNA/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Neoplasias/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Humanos , Neoplasias/enzimologia , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Poli ADP Ribosilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Bibliotecas de Moléculas Pequenas/química
19.
Cancer Manag Res ; 11: 6703-6717, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410061

RESUMO

Introduction: Cancer-related fatigue (CRF) is the most debilitating symptom with the greatest adverse side effect on quality of life. The etiology of this symptom is still not understood. The purpose of this study was to examine the relationship between mitochondrial gene expression, mitochondrial oxidative phosphorylation, electron transport chain complex activity, and fatigue in prostate cancer patients undergoing radiotherapy (XRT), compared to patients on active surveillance (AS). Methods: The study used a matched case-control and repeated-measures research design. Fatigue was measured using the revised Piper Fatigue Scale from 52 patients with prostate cancer. Mitochondrial oxidative phosphorylation, electron-transport chain enzymatic activity, and BCS1L gene expression were determined using patients' peripheral mononuclear cells. Data were collected at three time points and analyzed using repeated measures ANOVA. Results: The fatigue score was significantly different over time between patients undergoing XRT and AS (P<0.05). Patients undergoing XRT experienced significantly increased fatigue at day 21 and day 42 of XRT (P<0.01). Downregulated mitochondrial gene (BC1, ubiquinol-cytochrome c reductase, synthesis-like, BCS1L, P<0.05) expression, decreased OXPHOS-complex III oxidation (P<0.05), and reduced activity of complex III were observed over time in patients with XRT. Moreover, increased fatigue was significantly associated with downregulated BCS1L and decreased complex III oxidation in patients undergoing XRT. Conclusion: Our results suggest that BCS1L and complex III in mitochondrial mononuclear cells are potential biomarkers and feasible therapeutic targets for acute XRT-induced fatigue in this clinical population.

20.
Am J Cancer Res ; 9(3): 479-495, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949405

RESUMO

Nasopharyngeal carcinoma (NPC), arising from the nasopharynx epithelium, is prevalent among South and East Asia. The radiotherapy is the primary treatment for NPC patients. However, the acquired radioresistance dramatically diminishes the therapeutic effect of radiotherapy. Meanwhile, recurrence and metastasis always occur in line with the radioresistance, but the underlying mechanisms are still unclear. In this study, we established two radioresistant NPC cell lines, CNE1R and SUNE1R, by sequentially irradiated parental CNE1 and SUNE1 cells up to a clinical treatment dose of 72 Gy. A transcriptome profile analysis of CNE1R and CNE1 reveals that activated oncogenic pathways are highly enriched in CNE1R. As the result, CNE1R showed higher proliferation rate but lower apoptosis rate after irradiation, and enhanced metastasis ability in comparison with CNE1. Significantly, a group of metastasis associated genes were increased in CNE1R while the irradiation proceeded, including several matrix metallopeptidase (MMP) members, especially MMP10 and MMP13. With further analysis, we found both MMP10 and MMP13 are highly upregulated in metastatic head and neck cancer specimens compared to non-metastatic ones. More importantly, patients with lower expression of both MMP10 and MMP13 showed a better five-year survival than the double high group. Our findings unveiled the potential mechanisms of radioresistance related metastasis in NPC patients, and the increase of MMP10 and MMP13 may serve as high risk factors for metastasis during radiotherapy.

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