Advances in targeted therapies for hepatocellular carcinoma in the genomic era

Mortality owing to liver cancer has increased in the past 20 years, and the latest estimates indicate that the global health burden of this disease will continue to grow. Most patients with hepatocellular carcinoma (HCC) are still diagnosed at intermediate or advanced disease stages, where curative approaches are often not feasible. Among the treatment options available, the molecular targeted agent sorafenib is able to significantly increase overall survival in these patients. Thereafter, up to seven large, randomized phase III clinical trials investigating other molecular therapies in the first-line and second-line settings have failed to improve on the results observed with this agent. Potential reasons for this include intertumour heterogeneity, issues with trial design and a lack of predictive biomarkers of response. During the past 5 years, substantial advances in our knowledge of the human genome have provided a comprehensive picture of commonly mutated genes in patients with HCC. This knowledge has not yet influenced clinical decision-making or current clinical practice guidelines. In this Review the authors summarize the molecular concepts of progression, discuss the potential reasons for clinical trial failure and propose new concepts of drug development, which might lead to clinical implementation of emerging targeted agents.

Correction: Usage of Complementary Medicine in Switzerland: Results of the Swiss Health Survey 2012 and Development Since 2007.

[This corrects the article DOI: 10.1371/journal.pone.0141985.]

Targeted therapies for small cell lung cancer: Where do we stand?

Small cell lung cancer (SCLC) accounts for 15% of lung cancer cases and is associated with a dismal prognosis. Standard therapeutic regimens have been improved over the past decades, but without a major impact on patient survival. The development of targeted therapies based on a better understanding of the molecular basis of the disease is urgently needed. At the genetic level, SCLC appears very heterogenous, although somatic mutations targeting classical oncogenes and tumor suppressors have been reported. SCLC also possesses somatic mutations in many other cancer genes, including transcription factors, enzymes involved in chromatin modification, receptor tyrosine kinases and their downstream signaling components. Several avenues have been explored to develop targeted therapies for SCLC. So far, however, there has been limited success with these targeted approaches in clinical trials. Further progress in the optimization of targeted therapies for SCLC will require the development of more personalized approaches for the patients.

Preclinical modeling of multi-drug cancer therapies

Anticancer drugs typically are administered in the clinic in the form of mixtures, sometimes called combinations. Only in rare cases, however, are mixtures approved as drugs. Rather, research on mixtures tends to occur after single drugs have been approved. The goal of this research project was to develop modeling approaches that would encourage rational preclinical mixture design. To this end, a series of models were developed. First, several QSAR classification models were constructed to predict the cytotoxicity, oral clearance, and acute systemic toxicity of drugs. The QSAR models were applied to a set of over 115,000 natural compounds in order to identify promising ones for testing in mixtures. Second, an improved method was developed to assess synergistic, antagonistic, and additive effects between drugs in a mixture. This method, dubbed the MixLow method, is similar to the Median-Effect method, the de facto standard for assessing drug interactions. The primary difference between the two is that the MixLow method uses a nonlinear mixed-effects model to estimate parameters of concentration-effect curves, rather than an ordinary least squares procedure. Parameter estimators produced by the MixLow method were more precise than those produced by the Median-Effect Method, and coverage of Loewe index confidence intervals was superior. Third, a model was developed to predict drug interactions based on scores obtained from virtual docking experiments. This represents a novel approach for modeling drug mixtures and was more useful for the data modeled here than competing approaches. The model was applied to cytotoxicity data for 45 mixtures, each composed of up to 10 selected drugs. One drug, doxorubicin, was a standard chemotherapy agent and the others were well-known natural compounds including curcumin, EGCG, quercetin, and rhein. Predictions of synergism/antagonism were made for all possible fixed-ratio mixtures, cytotoxicities of the 10 best-scoring mixtures were tested, and drug interactions were assessed. Predicted and observed responses were highly correlated (r2 = 0.83). Results suggested that some mixtures allowed up to an 11-fold reduction of doxorubicin concentrations without sacrificing efficacy. Taken together, the models developed in this project present a general approach to rational design of mixtures during preclinical drug development. ^

The results of a barrier analysis on complementary feeding practices among mothers in the Central River Division of the Gambia

Currently, the barriers to appropriate infant feeding practices are largely unknown in the Central River Division of the Gambia. A questionnaire was developed and implemented by a local Non Governmental Organization (NGO), the Gambia Food and Nutrition Agency, in order to gain more information and ultimately to improve the child mortality rate of the country. There were two participant groups: 88 Doers who are women who had adopted the appropriate complementary feeding practice guidelines as defined by the World Health Organization and 87 Non Doers who are women who had in some way strayed from the appropriate complementary feeding practice guidelines. The questionnaire included aspects of the Health Belief Model which can be used in the development of a future intervention. The Yes/No questions were analyzed using the Chi-square statistical method and the open-ended questions used a descriptive analysis method of evaluation. The constructs for perceived susceptibility, perceived action efficacy, perceived self efficacy, cues for action and perception of divine showed significant differences between the Doers and the Non Doers (p<0.05). The descriptive analysis revealed that both participant groups had a limited understanding of the preventative qualities of the adoption of appropriate complementary feeding practices. The women in both of groups also showed a strong perception of divine will. Women in the Central River Division perceive their husband and in-laws to be the most influential in the decision-making process regarding infant feeding practices. Recommendations for future interventions must acknowledge the importance and influence of the community surrounding the women in their adoption of the appropriate infant feeding practices. It would also be important to educate women about of the specific guidelines of the appropriate complementary feeding practices, specifically the delay in early initiation of complementary feeding. The results of this barrier analysis provide useful information to plan and implement an effective intervention to improve the child mortality rate in the Gambia. ^

Application of cell line based genomic predictors to predict response to targeted therapies in breast cancer

Cancer cell lines can be treated with a drug and the molecular comparison of responders and non-responders may yield potential predictors that could be tested in the clinic. It is a bioinformatics challenge to apply the cell line-derived multivariable response predictors to patients who respond to therapy. Using the gene expression data from 23 breast cancer cell lines, I developed three predictors of dasatinib sensitivity by selecting differentially expressed genes and applying different classification algorithms. The performance of these predictors on independent cell lines with known dasatinib response was tested. The predictor based on weighted voting method has the best overall performance. It correctly predicted dasatinib sensitivity in 11 out of 12 (92%) breast and 17 out of 23 (74%) lung cancer cell lines. These predictors were then applied to the gene expression data from 133 breast cancer patients in an attempt to predict how the patients might respond to dasatinib therapy. Two predictors identified 13 patients in common to be dasatinib sensitive. Sixty two percent of these cases are triple negative (ER-negative, HER2-negative and PR-negative) and 76% are double negative. The result is consistent with the findings from other studies, which identified a target population for dasatinib treatment to be triple negative or basal breast cancer subtype. In conclusion, we think that the cell line-derived dasatinib classifiers can be applied to the human patients. ^

Quality of life, symptom experience, and use of complementary and alternative medicine among women with ovarian cancer

The objectives of this dissertation were to determine the quality of life in women with ovarian cancer and the association of their physical and emotional well-being with the number of symptoms, duration of symptoms, and the scores of common symptoms of ovarian cancer; to study the prevalence of complementary and alternative medicine techniques for symptom relief and its association with the number of symptoms, age, education, insurance, comorbidity, and satisfaction with medical care they received, and their pre-diagnostic experience of symptoms.^ This study was based on a secondary data analysis of a study of early detection of ovarian cancer. A sample of 139 women with ovarian cancer was recruited and was administered a questionnaire comprised of questions on their quality of life, their symptoms and what they did about the symptoms, whether they used any complementary and alternative medicine techniques, and other medical conditions they had. Out of this sample, 53 patients underwent in-depth interviews relating to their symptoms before the diagnosis and their experiences with the health care system leading to the ovarian cancer diagnosis. ^ In article #1, ovarian cancer patients were observed to have significantly poorer quality of life on all subscales and summary scores except pain, compared to that of the general population of US women. Physical well-being scores were negatively associated with the number of symptoms before diagnosis and a significant negative association of comorbidity index was observed with physical well-being. Higher education and increase in time since diagnosis was found to have better physical scores. Emotional well-being scores showed marginally significant associations with number of symptoms and bloating. ^ In article #2, a thematic content analysis of the ovarian cancer patients’ interviews revealed that on recognition of their symptoms women first assumed their symptoms to be a normal transient occurrence due to a pre-existing disease condition, or due to some other disease. A series of misattributions of their symptoms on their and their doctors’ part impacted their health care seeking.In article #3, a significantly greater likelihood of CAM use with an increase in the number of symptoms was observed.^ Based on the foregoing results, it is important to educate women on possible signs of ovarian cancer and also to educate doctors about the results of current research regarding ovarian cancer diagnosis. This will help to avoid a delay in getting a diagnosis and improve women’s quality of life. It emphasizes the diagnosis of ovarian cancer in earlier stages by more sensitive screening techniques. This study emphasizes the importance of consideration of comorbidity in any quality of life research. Additionally, educating women in the safe use of CAM techniques carries immense significance because the efficacy and safety of many of the currently advertized CAM products has not been scientifically validated. Further research is needed to confirm the findings of this study. ^

Quantitative comparison of late effects following photon versus proton external-beam radiation therapies: Toward an evidence-based approach to selecting a treatment modality

Radiation therapy has been used as an effective treatment for malignancies in pediatric patients. However, in many cases, the side effects of radiation diminish these patients’ quality of life. In order to develop strategies to minimize radiogenic complications, one must first quantitatively estimate pediatric patients’ relative risk for radiogenic late effects, which has not become feasible till recently because of the calculational complexity. The goals of this work were to calculate the dose delivered to tissues and organs in pediatric patients during contemporary photon and proton radiotherapies; to estimate the corresponding risk of radiogenic second cancer and cardiac toxicity based on the calculated doses and on dose-risk models from the literature; to test for the statistical significance of the difference between predicted risks after photon versus proton radiotherapies; and to provide a prototype of an evidence-based approach to selecting treatment modalities for pediatric patients, taking second cancer and cardiac toxicity into account. The results showed that proton therapy confers a lower predicted risk of radiogenic second cancer, and lower risks of radiogenic cardiac toxicities, compared to photon therapy. An uncertainty analysis revealed that the qualitative findings of this study are insensitive to changes in a wide variety of host and treatment related factors.

Evaluating alternative therapies. Support/imagery and immune function in breast cancer: A pilot study

Cancer patients increasingly request alternative therapies such as imagery techniques and support groups. Although research suggests evidence of enhanced psychosocial functioning with supportive group therapy and enhanced immune function with imagery techniques, studies are anecdotal or limited to case studies or descriptive reports. The efficacy of these alternative therapies should be validated by randomized, controlled trials and the mechanisms of action mediating immune function and outcome examined.^ In a 12-month pilot study, we evaluate the feasibility of conducting a controlled study with clinical trial methodology to test the effects of imagery/relaxation and support on quality of life, emotional well-being, and immune function for women after breast cancer. Using a randomized pre-post test design with three intervention waves, we assigned women (n = 47) to either standard care (n = 15), standard care plus 6-weekly support sessions (n = 16) or imagery/relaxation sessions (n = 16).^ The primary aim of this pilot study is to determine the feasibility of conducting a clinical trial of alternative therapies in a clinical care setting. Secondary aims are to determine parameter estimates for the effects of the two treatment groups on quality of life, coping, social support, and immune function and describe methodology issues related to trials of alternative therapies.^ The research provides direction for future studies of alternative therapies by describing the recruitment, clinical trial experience, and related methodology issues. The study extends previous work by differentiating the effects of support group from mental imagery among outpatient groups who are homogeneous regarding cancer type and treatment stage. The study provides data for future longitudinal studies of disease progression by differentiating the effectiveness of interventions designed to enhance quality of life, coping, social support, and immune function and subsequently, alter the clinical course of disease. ^

BIM MEDIATES IMATINIB-INDUCED APOPTOSIS OF GASTROINTESTINAL STROMAL TUMORS: TRANSLATIONAL IMPLICATIONS

Gastrointestinal stromal tumors (GISTs) are oncogene-addicted cancers driven by activating mutations in the genes encoding receptor tyrosine kinases KIT and PDGFR-α. Imatinib mesylate, a specific inhibitor of KIT and PDGFR-α signaling, delays progression of GIST, but is incapable of achieving cure. Thus, most patients who initially respond to imatinib therapy eventually experience tumor progression, and have limited therapeutic options thereafter. To address imatinib-resistance and tumor progression, these studies sought to understand the molecular mechanisms that regulate apoptosis in GIST, and evaluate combination therapies that kill GISTs cells via complementary, but independent, mechanisms. BIM (Bcl-2 interacting mediator of apoptosis), a pro-apoptotic member of the Bcl-2 family, effects apoptosis in oncogene-addicted malignancies treated with targeted therapies, and was recently shown to mediate imatinib-induced apoptosis in GIST. This dissertation examined the molecular mechanism of BIM upregulation and its cytotoxic effect in GIST cells harboring clinically-representative KIT mutations. Additionally, imatinib-induced alterations in BIM and pro-survival Bcl-2 proteins were studied in specimens from patients with GIST, and correlated to apoptosis, FDG-PET response, and survival. Further, the intrinsic pathway of apoptosis was targeted therapeutically in GIST cells with the Bcl-2 inhibitor ABT-737. These studies show that BIM is upregulated in GIST cells and patient tumors after imatinib exposure, and correlates with induction of apoptosis, response by FDG-PET, and disease-free survival. These studies contribute to the mechanistic understanding of imatinib-induced apoptosis in clinically-relevant models of GIST, and may facilitate prediction of resistance and disease progression in patients. Further, combining inhibition of KIT and Bcl-2 induces apoptosis synergistically and overcomes imatinib-resistance in GIST cells. Given that imatinib-resistance and GIST progression may reflect inadequate BIM-mediated inhibition of pro-survival Bcl-2 proteins, the preclinical evidence presented here suggests that direct engagement of apoptosis may be an effective approach to enhance the cytotoxicity of imatinib and overcome resistance.

Identifying and Targeting Molecular Deregulations in Uterine Leiomyosarcoma: A Role for mTOR Inhibition-Based Combination Therapies

Uterine leiomyosarcoma (ULMS) is an aggressive malignancy characterized by marked chemoresistance, frequent relapses, and poor outcome. Despite efforts to improve survival over the past several decades, only minimal advances have been made. Hence, there is an urgent and unmet need for better understanding of the molecular deregulations that underlay ULMS and development of more effective therapeutic strategies. This work identified several common deregulations in a large (n=208) tissue microarray of ULMS compared to GI smooth muscle, myometrium, and leiomyoma controls. Our results suggest that significant loss of smooth muscle and gynecological differentiation markers is common in ULMS, a finding that could help render improved ULMS diagnosis, especially for advanced disease. Similarly to reports in other malignancies, we found that several cancer-related proteins were differentially expressed; these could be useful together as biomarkers for ULMS. Notably, we identified significant upregulation and overexpression of the mTOR pathway in ULMS, examined the possible contribution of tyrosine kinase receptor deregulation promoting mTOR activation, and unraveled a role for pS6RP and p4EBP1 as molecular disease prognosticators. The significance of mTOR activation in ULMS and its potential as a therapeutic target were further investigated. Rapamycin abrogated ULMS cell growth and cell cycle progression in vitro but induced only sight growth delay in vivo. Given that effective mTOR therapies likely require combination mTOR blockade with inhibition of other targets, coupled with recent observations suggesting that Aurora A kinase (Aurk A) deregulations commonly occur in ULMS, the preclinical impact of dually targeting both pathways was evaluated. Combined therapy with rapamycin (an mTORC1 inhibitor) and MLN8237 (an investigational Aurk A inhibitor) profoundly and synergistically abrogated ULMS growth in vitro. Interestingly, the superior effects were noted only when MLN8237 was pre-administered. This novel therapeutic combination and scheduling regimen resulted in marked tumor growth inhibition in vivo. Together, these data support further exploration of dual mTOR and Aurk A blockade for the treatment of human ULMS.

Mind-body therapy use among U.S. children and adolescents

The use of complementary and alternative medicine (CAM) has increased dramatically in the United States in the past several decades. While botanicals and dietary supplements have received the majority of attention in the popular and scholarly literature on alternative therapies, mind-body therapies, such as biofeedback, meditation, hypnosis, massage and chiropractic care presently constitute a large portion of the American public's use of CAM. The present study explores the patterns and prevalence of such therapy use among an under-studied population of CAM users: children and adolescents. Using data from the 2007 National Health Interview Survey, this paper describes the prevalence, patterns, and predictors of mind-body therapy use among a nationally representative sample of children (n=9,417) using a multidimensional model of health care behavior. The contribution of predisposing, enabling, and medical factors to mind-body therapy use among children will be also examined. Results provide additional evidence to a growing body of literature documenting that children and adolescents increasingly turn to mind-body therapies to alleviate symptoms, cope with chronic or life-threatening diseases, and to promote overall well-being. ^

Adherence to HIV /AIDS therapies among low -literacy populations: The ALP project

Adherence to HIV/AIDS therapies has been an important health problem since the early 1980s when AZT was first prescribed as a therapy for HIV/AIDS. It became particularly important between 1995 and 1997 with the advent of protease inhibitors (Chesney, Ickovics, Hecht, Sikipa, & Rabkin J., 1999) and became even more significant as persons with HIV/AIDS began to develop resistance to medications. Low-literacy populations have poorer health (Brez & Taylor, 1997) and higher AIDS rates (Simon, Hu, Diaz, & Kerndt, 1995), than their higher literacy counterparts due to delayed treatment (Baker, Parker, Williams, Clark, & Nurss, 1997), shame of literacy skills (Parikh, 1996), and poor access to care (Williams, et al., 1995). Poorer health and higher AIDS rates can also be attributed to poor patient-provider relationships (Crespo-Fierro, 1997; Eldred, Wu, Chaisson, & Moore, 1998) to a poorer understanding of medical protocols (Murphy, 1997), and inadequate patient education (Ungvarski, 1997; Davis, Michielutte, Askov, Williams, & Weiss, 1998, Doak, Doak, & Root, 1996). ^ The ALP intervention was developed for HIV positive low-literacy populations of African American women in Houston, Texas. The intervention was based on a needs assessment, using the PRECEDE model, an innovative process referred to as Intervention Mapping, and validated using formative evaluation methods with 54 individuals. The needs assessment resulted in a list of behavioral, environmental, predisposing, enabling, and reinforcing determinants of adherence. The Intervention Mapping framework was used to refine these determinants and develop a list of objectives describing what must be learned or changed to for the target population to adhere to HIV/AIDS therapies. Methods and strategies, were developed using theoretical constructs from the Health Belief Model (Rosenstock, 1974) and Social Cognitive Theory (Bandura, 1986). These theories, empirical evidence, and information from the target population indicated that perceived susceptibility, perceived severity, outcome expectations, and self-efficacy were important and changeable determinants of adherence to HIV/AIDS therapies for this population. ^ These components were brought together in the form of a theory-based color cartoon book and 10-minute cassette tape. The book was developed for people with 2.9 years of U.S. education as measured with the Flesch-Kincaid Grade Level method and the script was recorded onto a cassette tape to make it suitable for populations with even lower-literacy skills. A formative evaluation was conducted to ensure that the content and structure were accurate, clear, realistic, readable, appropriate, and likely to be used as intended. ^

Are trading partners complementary in international trade?

We use a unique dataset on trading transactions at the firm level to investigate a complementary effect in international transactions between sellers and buyers; trading transactions are more likely to be international when both sellers and buyers are large in size than when either sellers or buyers are large. Our econometric analysis provides evidence for the complementary effect between trading partners on the likelihood of international trade, which is most prominent for exports from North to South.