Molecular characterization of breast cancer cell lines through multiple omic approaches.

BACKGROUND: Breast cancer cell lines are frequently used as model systems to study the cellular properties and biology of breast cancer. Our objective was to characterize a large, commonly employed panel of breast cancer cell lines obtained from the American Type Culture Collection (ATCC 30-4500 K) to enable researchers to make more informed decisions in selecting cell lines for specific studies. Information about these cell lines was obtained from a wide variety of sources. In addition, new information about cellular pathways that are activated within each cell line was generated. METHODS: We determined key protein expression data using immunoblot analyses. In addition, two analyses on serum-starved cells were carried out to identify cellular proteins and pathways that are activated in these cells. These analyses were performed using a commercial PathScan array and a novel and more extensive phosphopeptide-based kinome analysis that queries 1290 phosphorylation events in major signaling pathways. Data about this panel of breast cancer cell lines was also accessed from several online sources, compiled and summarized for the following areas: molecular classification, mRNA expression, mutational status of key proteins and other possible cancer-associated mutations, and the tumorigenic and metastatic capacity in mouse xenograft models of breast cancer. RESULTS: The cell lines that were characterized included 10 estrogen receptor (ER)-positive, 12 human epidermal growth factor receptor 2 (HER2)-amplified and 18 triple negative breast cancer cell lines, in addition to 4 non-tumorigenic breast cell lines. Within each subtype, there was significant genetic heterogeneity that could impact both the selection of model cell lines and the interpretation of the results obtained. To capture the net activation of key signaling pathways as a result of these mutational combinations, profiled pathway activation status was examined. This provided further clarity for which cell lines were particularly deregulated in common or unique ways. CONCLUSIONS: These two new kinase or "Kin-OMIC" analyses add another dimension of important data about these frequently used breast cancer cell lines. This will assist researchers in selecting the most appropriate cell lines to use for breast cancer studies and provide context for the interpretation of the emerging results.

Epigenetic silencing of CREB3L1 by DNA methylation is associated with high-grade metastatic breast cancers with poor prognosis and is prevalent in triple negative breast cancers.

BACKGROUND: CREB3L1 (cAMP-responsive element-binding protein 3-like protein 1), a member of the unfolded protein response, has recently been identified as a metastasis suppressor in both breast and bladder cancer. METHODS: Quantitative real time PCR (qPCR) and immunoblotting were used to determine the impact of histone deacetylation and DNA methylation inhibitors on CREB3L1 expression in breast cancer cell lines. Breast cancer cell lines and tumor samples were analyzed similarly, and CREB3L1 gene methylation was determined using sodium bisulfite conversion and DNA sequencing. Immunohistochemistry was used to determine nuclear versus cytoplasmic CREB3L1 protein. Large breast cancer database analyses were carried out to examine relationships between CREB3L1 gene methylation and mRNA expression in addition to CREB3L1 mRNA expression and prognosis. RESULTS: This study demonstrates that the low CREB3L1 expression previously seen in highly metastatic breast cancer cell lines is caused in part by epigenetic silencing. Treatment of several highly metastatic breast cancer cell lines that had low CREB3L1 expression with DNA methyltransferase and histone deacetylase inhibitors induced expression of CREB3L1, both mRNA and protein. In human breast tumors, CREB3L1 mRNA expression was upregulated in low and medium-grade tumors, most frequently of the luminal and HER2 amplified subtypes. In contrast, CREB3L1 expression was repressed in high-grade tumors, and its loss was most frequently associated with triple negative breast cancers (TNBCs). Importantly, bioinformatics analyses of tumor databases support these findings, with methylation of the CREB3L1 gene associated with TNBCs, and strongly negatively correlated with CREB3L1 mRNA expression. Decreased CREB3L1 mRNA expression was associated with increased tumor grade and reduced progression-free survival. An immunohistochemistry analysis revealed that low-grade breast tumors frequently had nuclear CREB3L1 protein, in contrast to the high-grade breast tumors in which CREB3L1 was cytoplasmic, suggesting that differential localization may also regulate CREB3L1 effectiveness in metastasis suppression. CONCLUSIONS: Our data further strengthens the role for CREB3L1 as a metastasis suppressor in breast cancer and demonstrates that epigenetic silencing is a major regulator of the loss of CREB3L1 expression. We also highlight that CREB3L1 expression is frequently altered in many cancer types suggesting that it could have a broader role in cancer progression and metastasis.

Children's proneness to shame and guilt predict risky and illegal behaviors in young adulthood.

Do shame and guilt help people avoid doing wrong? Although some research suggests that guilt-proneness is a protective factor while shame-proneness puts individuals at risk, most research is either cross-sectional or short-term. In this longitudinal study, 380 5th graders (ages 10-12) completed measures of proneness to shame and guilt. We re-interviewed 68 % of participants after they turned 18 years old (range 18-21). Guilt-proneness assessed in childhood predicted fewer sexual partners, less use of illegal drugs and alcohol, and less involvement with the criminal justice system. Shame-proneness, in contrast, was a risk factor for later deviant behavior. Shame-prone children were more likely to have unprotected sex and use illegal drugs in young adulthood. These results held when controlling for childhood SES and teachers' ratings of aggression. Children's moral emotional styles appear to be well established by at least middle childhood, with distinct downstream implications for risky behavior in early adulthood.

HIV risk behaviors of male and female jail inmates prior to incarceration and one year post-release.

Individuals cycling in and out of the criminal justice system are at high risk for contracting HIV/AIDS. Most infections are contracted in the community, not during incarceration, but little is known about the profile of risk behaviors responsible for this elevated infection rate. This study investigated pre-incarceration and post-release HIV risk behaviors in a longitudinal study of 542 male and female inmates in a Northern Virginia jail. Although there was a significant decrease in risky behavior from pre-incarceration to post-incarceration, participants reported high levels of unprotected sexual activity and risky IV drug behaviors at both time points, emphasizing the need for prevention programming among this at-risk population. Gender differences in participants' pre-incarceration and post-release HIV risk behaviors suggest the need for gender-specific interventions to reduce overall HIV risk. Identifying specific HIV risk behaviors of jail inmates is vital to improve treatment and intervention efforts inside and outside of correctional settings.

Exercise Programming Modelling a Standard of Care Approach Improves Physical Health and Patient-Reported Outcomes in Individuals Living with Breast Cancer: A Pilot Study.

Controlled study designs widely report that exercise improves the health of individuals living with breast cancer. Still, many individuals living with breast cancer are not active enough to experience the benefits of exercise. The Activating Cancer Communities through an Exercise Strategy for Survivors study was developed to reach more individuals living with cancer. This report describes the effects of a 12-week individualized exercise program that models a standard-of-care approach on body composition, physical fitness, and patient-reported outcomes in individuals living with breast cancer. Individuals living with breast cancer were recruited for the study and completed an exercise program twice weekly overseen by a Clinical Exercise Physiologist. A total of 43 participants completed the exercise intervention, and 36 withdrew from the study. All participants had significantly improved aerobic fitness, waist circumference, hip circumference, lower body endurance, physical activity behaviour, health-related quality of life, emotional status, and fatigue levels after completing the program. Flexibility, balance, and sleep scores did not change. The results from the 12-week individualized exercise program largely align with the results from more controlled study designs. These results support future initiatives integrating exercise therapy into the standard of care for individuals living with breast cancer.

Reduced CREB3L1 expression in triple negative and luminal a breast cancer cells contributes to enhanced cell migration, anchorage-independent growth and metastasis.

Women with metastatic breast cancer have a disheartening 5-year survival rate of only 28%. CREB3L1 (cAMP-responsive element binding protein 3 like 1) is a metastasis suppressor that functions as a transcription factor, and in an estrogen-dependent model of rat breast cancer, it repressed the expression of genes that promote breast cancer progression and metastasis. In this report, we set out to determine the expression level of CREB3L1 across different human breast cancer subtypes and determine whether CREB3L1 functions as a metastasis suppressor, particularly in triple negative breast cancers (TNBCs). CREB3L1 expression was generally increased in luminal A, luminal B and HER2 breast cancers, but significantly reduced in a high proportion (75%) of TNBCs. Two luminal A (HCC1428, T47D) and two basal TNBC (HCC1806, HCC70) CREB3L1-deficient breast cancer cell lines were characterized as compared to their corresponding HA-CREB3L1-expressing counterparts. HA-CREB3L1 expression significantly reduced both cell migration and anchorage-independent growth in soft agar but had no impact on cell proliferation rates as compared to the CREB3L1-deficient parental cell lines. Restoration of CREB3L1 expression in HCC1806 cells was also sufficient to reduce mammary fat pad tumor formation and lung metastases in mouse xenograft models of breast cancer as compared to the parental HCC1806 cells. These results strongly support a metastasis suppressor role for CREB3L1 in human luminal A and TNBCs. Further, the ability to identify the subset of luminal A (7%) and TNBCs (75%) that are CREB3L1-deficient provides opportunities to stratify patients that would benefit from additional treatments to treat their more metastatic disease.

Homoharringtonine demonstrates a cytotoxic effect against triple-negative breast cancer cell lines and acts synergistically with paclitaxel.

The lack of targeted therapies for triple-negative breast cancer (TNBC) contributes to their high mortality rates and high risk of relapse compared to other subtypes of breast cancer. Most TNBCs (75%) have downregulated the expression of CREB3L1 (cAMP-responsive element binding protein 3 like 1), a transcription factor and metastasis suppressor that represses genes that promote cancer progression and metastasis. In this report, we screened an FDA-approved drug library and identified four drugs that were highly cytotoxic towards HCC1806 CREB3L1-deficient TNBC cells. These four drugs were: (1) palbociclib isethionate, a CDK4/6 inhibitor, (2) lanatocide C (also named isolanid), a Na+/K+-ATPase inhibitor, (3) cladribine, a nucleoside analog, and (4) homoharringtonine (also named omacetaxine mepesuccinate), a protein translation inhibitor. Homoharringtonine consistently showed the most cytotoxicity towards an additional six TNBC cell lines (BT549, HCC1395, HCC38, Hs578T, MDA-MB-157, MDA-MB-436), and several luminal A breast cancer cell lines (HCC1428, MCF7, T47D, ZR-75-1). All four drugs were then separately evaluated for possible synergy with the chemotherapy agents, doxorubicin (an anthracycline) and paclitaxel (a microtubule stabilizing agent). A strong synergy was observed using the combination of homoharringtonine and paclitaxel, with high cytotoxicity towards TNBC cells at lower concentrations than when each was used separately.

The Impact of Exercise on Cardiotoxicity in Pediatric and Adolescent Cancer Survivors: A Scoping Review.

Childhood and adolescent cancer survivors are disproportionately more likely to develop cardiovascular diseases from the late effects of cardiotoxic therapies (e.g., anthracycline-based chemotherapy and chest-directed radiotherapy). Currently, dexrazoxane is the only approved drug for preventing cancer treatment-related cardiac damage. While animal models highlight the beneficial effects of exercise cancer treatment-related cardiac dysfunction, few clinical studies have been conducted. Thus, the objective of this scoping review was to explore the designs and impact of exercise-based interventions for managing cancer treatment-related cardiac dysfunction in childhood and adolescent cancer survivors. Reviewers used Joanna Briggs Institute's methodology to identify relevant literature. Then, 4616 studies were screened, and three reviewers extracted relevant data from six reports. Reviewers found that exercise interventions to prevent cancer treatment-related cardiac dysfunction in childhood and adolescent cancer survivors vary regarding frequency, intensity, time, and type of exercise intervention. Further, the review suggests that exercise promotes positive effects on managing cancer treatment-related cardiac dysfunction across numerous indices of heart health. However, the few clinical studies employing exercise interventions for childhood and adolescent cancer survivors highlight the necessity for more research in this area.

N-terminal residues of the yeast pheromone receptor, Ste2p, mediate mating events independently of G1-arrest signaling.

In Saccharomyces cerevisiae, mechanisms modulating the mating steps following cell cycle arrest are not well characterized. However, the N-terminal domain of Ste2p, a G protein-coupled pheromone receptor, was recently proposed to mediate events at this level. Toward deciphering receptor mechanisms associated with this mating functionality, scanning mutagenesis of targeted regions of the N-terminal domain has been completed. Characterization of ste2 yeast overexpressing Ste2p variants indicated that residues Ile 24 and Ile 29 as well as Pro 15 are critical in mediating mating efficiency. This activity was shown to be independent of Ste2p mediated G1 arrest signaling. Further analysis of Ile 24 and Ile 29 highlight the residues' solvent accessibility, as well as the importance of the hydrophobic nature of the sites, and in the case of Ile 24 the specific size and shape of the side chain. Mutation of these Ile's led to arrest of mating after cell contact, but before completion of cell wall degradation. We speculate that these extracellular residues mediate novel receptor interactions with ligand or proteins, leading to stimulation of alternate signaling effector pathways.

Health care access, use, and satisfaction among disabled Medicaid beneficiaries.

Despite being a vulnerable and costly population, little is known about disabled Medicaid beneficiaries. Using data from a 1999-2000 survey, we describe the population and their health care experiences in terms of access, use, and satisfaction with care. Results indicate that disabled beneficiaries are a unique population with wide-ranging circumstances and health conditions. Our results on access to care were indeterminate: by some measures, they had good access, but by others they did not. Beneficiaries' assessments of their health care were more clear: The bulk of the sample rated one or more area of care as being fair or poor.

Access to care among disabled adults on Medicaid.

Although disabled individuals account for a disproportionate share of Medicaid expenditures, little is known about their health care needs and experiences. This article explores differences in access and use among key disability subgroups--adults with physical disabilities, mental illness, and mental retardation/development disabilities (MR/DD). We find that disabled Medicaid beneficiaries with mental illness and those with greater health and functional limitations face more difficulties in obtaining care. This suggests a need for changes in the system of care under Medicaid, including targeting efforts to improve access to individuals with specific types of disabilities.

Unmet need among rural Medicaid beneficiaries in Minnesota.

Given the vulnerabilities of rural residents and the health care issues faced by the Medicaid population generally, the combined effects of being on Medicaid and living in a rural area raise important questions about access to health care services. This study looks at a key dimension of health care access: unmet needfor health care services. The study relies on data from a 1998 survey of rural Minnesota Medicaid beneficiaries. An overall response rate of 70% was obtained. For this study, the sample is limited to women who were on Medicaid for the full 12 months prior to the survey, resulting in 900 respondents. The study finds that the rural Medicaid beneficiaries face high levels of unmet need: more than 1 in 3 reported either delaying or not getting doctor, hospital, or specialist care that theyfelt they needed. Although the study lacks direct measures of the consequences of the high levels of unmet need, there is evidence that greater emergency room use is associated with unmet need. The survey data cannot necessarily be generalized to other rural areas, and like all surveys, this one is subject to nonresponse bias as well as potential biases because of respondent recall and self-assessment of medical needs. Nevertheless, thesefindings are suggestive of negative consequences of unmet need for both Medicaid beneficiaries and program costs.

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