AI implementation in the UK landscape: Knowledge of AI governance, perceived challenges and opportunities, and ways forward for radiographers

INTRODUCTION

Despite the rapid increase of AI-enabled applications deployed in clinical practice, many challenges exist around AI implementation, including the clarity of governance frameworks, usability of validation of AI models, and customisation of training for radiographers. This study aimed to explore the perceptions of diagnostic and therapeutic radiographers, with existing theoretical and/or practical knowledge of AI, on issues of relevance to the field, such as AI implementation, including knowledge of AI governance and procurement, perceptions about enablers and challenges and future priorities for AI adoption.

METHODS

An online survey was designed and distributed to UK-based qualified radiographers who work in medical imaging and/or radiotherapy and have some previous theoretical and/or practical knowledge of working with AI. Participants were recruited through the researchers' professional networks on social media with support from the AI advisory group of the Society and College of Radiographers. Survey questions related to AI training/education, knowledge of AI governance frameworks, data privacy procedures, AI implementation considerations, and priorities for AI adoption. Descriptive statistics were employed to analyse the data, and chi-square tests were used to explore significant relationships between variables.

RESULTS

In total, 88 valid responses were received. Most radiographers (56.6 %) had not received any AI-related training. Also, although approximately 63 % of them used an evaluation framework to assess AI models' performance before implementation, many (36.9 %) were still unsure about suitable evaluation methods. Radiographers requested clearer guidance on AI governance, ample time to implement AI in their practice safely, adequate funding, effective leadership, and targeted support from AI champions. AI training, robust governance frameworks, and patient and public involvement were seen as priorities for the successful implementation of AI by radiographers.

CONCLUSION

AI implementation is progressing within radiography, but without customised training, clearer governance, key stakeholder engagement and suitable new roles created, it will be hard to harness its benefits and minimise related risks.

IMPLICATIONS FOR PRACTICE

The results of this study highlight some of the priorities and challenges for radiographers in relation to AI adoption, namely the need for developing robust AI governance frameworks and providing optimal AI training.

Abstract P5-19-04: The WISDOM study: Reducing sequential steps and implementing parallel workflows in pragmatic trials

Background:The WISDOM Study is a preference-tolerant pragmatic study, comparing annual mammograms to a risk-based screening. Eligibility includes women ages 40-74 years with no history of breast cancer or DCIS. Participants are enrolled to one study arm: annual screening or risk-based screening (includes genetic testing). Pragmatic trials often involve gathering real-time data over multiple time points. Collecting real-time data sequentially can limit enrollment, delay study assignments, and reduce participant engagement. The WISDOM Study has identified such bottlenecks and has implemented parallel workflows, reducing the overall wait time for participants to complete required study steps. These data highlight how moving participants through the study more efficiently can improve enrollment and retention and inform other pragmatic trials. Methods: WISDOM participants have the option to either choose their study arm or be randomized into one as part of the preference tolerant randomized trial design. Participants then complete breast health questionnaires and genetic testing (if in the risk-based arm). This information is analyzed by the WISDOM breast cancer risk assessment algorithm, the result of which is then communicated to the participant through a screening assignment letter (SAL). Specific data elements, such as breast density found participants’ mammogram reports and genetic testing results are required for study randomization process and risk assessment calculations, respectively. The WISDOM randomization algorithm is stratified by several factors, including breast cancer risk estimated using the Breast Cancer Surveillance Consortium (BCSC) model, which uses mammographic density as a key input variable. The study team changed the workflow to allow participants to proceed to randomization without specific information by imputing both density and risk. Additionally, a parallel workflow improvement process was implemented to obtain mammogram reports while genetic testing was being completed. Results: Before the weighted BCSC and imputed density algorithms were introduced, it took an average of 47 days to randomize participants after completion of the baseline enrollment questionnaires. Now, participants are randomized immediately which has reduced delays by 100%. Prior to implementing the parallel workflow for genetic testing and mammogram ascertainment, genetic testing kits were sent only after mammogram reports were collected and validated. The expected turnaround time for genetic testing results was 30-60 days and on average, results were returned to participants in 42 days. Streamlining the study design to obtain mammogram reports while participants complete their genetic testing has shortened the time for participants to receive their screening assignment letters (SALs) from an average of 160 days to 78 days, a reduction by 49%. In comparison, participants in the annual arm of the study who do not complete genetic testing, receive their SALs after an average of 38 days from enrollment. This is due to long wait times to obtain mammographic densities from outside medical facilities. Conclusions: Creating parallel data ascertainment workflows and reducing sequential steps in the study process has increased completion of individual enrollment activities. Participants now are randomized immediately upon joining the study and have access to their SALs and genetic results more rapidly. This approach eliminated randomization wait times and improved efficiency of the early in the enrollment process. We are evaluating the impact on participant retention going forward. Workflow efficiency is critical to improve the patient experience, and our learnings can inform future trial design, particularly for studies requiring data from outside sources.

Citation Format: Tomiyuri Lewis, Stephanie Flores, Leah Sabacan, Patricia Choy, Halle Thannickal, Yiwey Shieh, Jeffrey Tice, Elad Ziv, Lisa Madlensky, Martin Eklund, Christina Yau, Amie Blanco, Barry Tong, Deborah Goodman, Nancy Anderson, Heather Harvey, Steele Fors, Hannah L Park, Samrrah Raouf, Skye Stewart, Janet Wernisch, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Dolores Moorehead, Barbara A Parker, Alexander Borowsky, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Laura van ‘t Veer, Andrea Z LaCroix, Olufunmilayo I Olopade, Deepa Sheth, Agustin Garcia, Rachel Lancaster, Michael Plaza, Wisdom Study, Athena Breast Health Network Investigators, Advocate Partners, Allison S Fiscalini, Laura Esserman. The WISDOM study: Reducing sequential steps and implementing parallel workflows in pragmatic trials [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-19-04.

Abstract P5-19-01: The impact of streamlined processes and patient-directed messaging to improve enrollment in a remote, pragmatic clinical trial

Background Recent advances in technology have made it possible to conduct remote clinical trials that allow individuals to participate from home with comfort, privacy, and ease. Despite these advances, challenges persist in running remote trials, such as survey question redundancies, lack of patient-initiated data-sharing tools, and unclear patient communication around critical enrollment steps. The Women Informed to Screen Depending on Measures of risk (WISDOM) Study is a pragmatic, preference-tolerant randomized control breast cancer screening trial comparing personalized risk-based screening to traditional, annual screening. The study population includes women ages 40-74 without a history of breast cancer or DCIS. Since 2016, study enrollment has been available to all women in the U.S. who meet study eligibility criteria. Since October 2020, WISDOM has implemented multiple strategies to improve participant experience: participant-initiated data-sharing tools and clear participant messaging. This abstract presents the efficacy of these interventions as they relate to increasing patient enrollment in remote, pragmatic clinical trials. Methods The WISDOM Study online enrollment process includes registration, participant study arm selection or randomization, online consent, and enrollment (submission of multiple study surveys over a secure, online platform). Barriers to online enrollment were uncovered through an internally-conducted needs assessment of participants who enrolled between 2019-2020, and participant feedback obtained through phone interviews conducted by WISDOM’s embedded ethics study. Improvements to our online enrollment procedures were executed in October 2020 and included: improving the clarity of study arm selection options, streamlining data collection surveys, and enacting a secure, patient-initiated online data-sharing tool and an online portal feature with auto-launch of critical information. Study metrics were obtained through Google Analytics and Salesforce. Results Prior to the end of 2020, only 62% of the 30,046 participants who registered for the WISDOM Study completed study enrollment. After improving the enrollment process, of the 5,334 participants registered for the study between Jan-June 2021, 69% completed the enrollment process finishing both the online consent and survey forms. Conversion from consent to enrollment went from 78% in January 2020 to 93% in June 2021. Currently, 56% participants complete enrollment in one day. Streamlining online patient questionnaires led to an increase in completion rates, with 75% of participants completing their yearly surveys, compared to 59% prior to April 2021. A secure patient upload feature for data sharing led to 1,054 participants successfully sharing their mammogram reports with WISDOM between March - June 2021. Previously, mammogram reports were missing for 20% of enrolled participants. This feature has enabled WISDOM to process 300 additional mammogram reports per month. Integration of an auto-launch feature in the participant’s portal in Feb 2021 has led to a 17% increase in participants viewing their screening recommendations in Yr 1. Prior to auto-launch, only 59% (n=6328) of Yr 1 screening recommendations and 61% (n=3681) of genetic testing reports were viewed by participants. Since implementation, the numbers increased to 78% (n=8406) and 85% (n=5160), respectively. Conclusions. Streamlining data to the most essential elements, and minimizing the steps required to share clinical documents, complete questionnaires and open key study notification is essential to improving enrollment rates in virtual, pragmatic trials. Patient-initiated data-sharing tools such as the ability for participants to share documents through secure, online portals is one example of success.

Citation Format: Patricia Choy, Tomiyuri Lewis, Stephanie Flores, Leah Sabacan, Halle Thannickal, Steffanie Goodman, Yiwey Shieh, Lisa Madlensky, Jeffrey A. Tice, Elad Ziv, Martin Eklund, Amie Blanco, Barry Tong, Deborah Goodman, Nancy Anderson, Heather Harvey, Steele Fors, Hannah Lui Park, Antonia Petruse, Skye Stewart, Samrrah Raouf, Janet Wernisch, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Dolores Moorehead, Barbara A Parker, Alexander Borowsky, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Laura van 't Veer, Andrea Z LaCroix, Olufunmilayo I. Olopade, Deepa Sheth, Agustin Garcia, Rachel Lancaster, Jennifer James, Galen Joseph, Wisdom Study, Athena Breast Health Network Investigators and Advocates, Allison Stover Fiscallini, Laura Esserman. The impact of streamlined processes and patient-directed messaging to improve enrollment in a remote, pragmatic clinical trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-19-01.

Abstract OT-21-01: Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM)

Background: WISDOM is a 100,000 healthy women preference-tolerant, pragmatic study comparing traditional annual screening to personalized risk-based breast screening. The novelty of WISDOM personalized screening is the integration of previously validated genetic and clinical risk factors (age, family history, breast biopsy results, ethnicity, mammographic density) into a single risk assessment model that directs the starting age, timing, and frequency of screening. The goal of WISDOM is to determine if personalized screening, compared to annual screening, is as safe, less morbid, enables prevention, and is more accepted by women. The study is registered on ClinicalTrials.gov, NCT02620852. Methods: Women aged 40-74 years with no history of breast cancer, DCIS or previous double mastectomy can join the study online at wisdomstudy.org. Participants can either elect randomization or self-select a study arm. Then, they provide electronic consent and sign the Release for Medical Information via DocuSign. For all participants, 5-year risk of developing breast cancer is calculated according to the Breast Cancer Surveillance Consortium (BCSC) model. Participants in the personalized arm undergo panel-based mutation testing (BRCA1, BRCA2, TP53, PTEN, STK11, CDH1, ATM, PALB2, and CHEK2), and their 5-year risk is calculated using the BCSC score combined with a Polygenic Risk Score (BCSC-PRS) that includes 229 single nucleotide polymorphisms (SNPs) known to increase breast cancer risk. The SNPs and mutations are assessed by saliva-based testing through Color Genomics. Five-year risk level thresholds are used to stratify participants as low-, moderate- and high risk. Risk stratification determines age to start, stop, and frequency of screening in the personalized arm. Accrual: As of July 2020 the WISDOM Study is open to all eligible women in the United States. To date, 38,762 eligible women have registered, and 28,706 women have consented to participate in the trial. The median age is 56 years. Seventy-seven percent of participants are Caucasian, 2% African-American, 5% Asian, and 8% of self-reported Hispanic ethnicity. WISDOM is partnering with Blue Cross Blue Shield Association for regional plan opt-in coverage, self-insured companies (Salesforce, Genentech, Qualcomm, CalPERS) and Medi-Cal (Inland Empire Health Plan) using a coverage with evidence progression approach. Accrual expansion and diversity: To ensure that resulting data are meaningful and potentially practice-changing for all populations of women, the WISDOM Study is enhancing the diversity of our participant population by establishing WISDOM sites in diverse areas with large African-American (Alabama, Louisiana, Illinois) and Latina (Florida) populations. These new recruitment sites, intentionally selected for the diverse communities they serve, have established partnerships with community organizations and outreach navigators. Additionally, we have translated the WISDOM Study to Spanish to facilitate access by Latina communities. With the engagement of patient advocates and community partnerships, expanding diversity in the study population will strengthen our scientific knowledge of breast cancer risk and improve access to personalized breast cancer screening recommendations for all women. Enrollment will continue through 2022. Conclusions: Results of 5 years follow-up will enable us to demonstrate whether personalized screening improves outcomes for future patients and it improves healthcare value by reducing screen volumes and costs without jeopardizing outcomes.

Citation Format: Irene Acerbi, Allison Stover Fiscalini, Mandy Che, Yiwey Shieh, Lisa Madlensky, Jeffrey Tice, Elad Ziv, Martin Eklund, Amie Blanco, Barry Tong, Deborah Goodman, Lamees Nassereddine, Nancy Anderson, Heather Harvey, Steele Fors, Hannah L Park, Antonia Petruse, Skye Stewart, Janet Wernisch, Larissa Risty, Ian Hurley, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Leah Sabacan, Tianyi Wang, Barbara A Parker, Alexander Borowsky, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Melinda Talley, Laura van 't Veer, Andrea Z LaCroix, Olufunmilayo I Olopade, Deepa Sheth, Augustin Garcia, Rachel Lancaster, Wisdom Study and Athena Breast Health Network Investigators and Advocate Partners, Laura Esserman. Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-21-01.

Family readiness for evidence-based injury prevention and car seat safety in Jordan

Primary prevention involves developing positive health behaviours designed to avert adverse health outcomes, whereas evidence-based primary prevention adopts practices that reduce illness and injury. This study's objective was to determine whether families in Jordan would adopt car safety measures after participating in an evidence-based injury prevention programme. Parents of children attending a regional government hospital in Jordan took part in an evidence-based educational class on child car restraints and car safety, six months later follow-up phone calls were made to see if the parents implemented the knowledge obtained in the class. Fifty families participated in the injury prevention class. The results showed that the evidence-based class on child restraint systems led to the adoption of the three interventions by the parents. At the time of the class 45% of parents allowed their infants to sit in the front seat, in the lap of an adult, this was reduced to 12%, being a 33% reduction. In addition, for children aged 6-12 using a seat belt in the back seat, the parents reported that their children using a seat belt increased from 13% to 70%. Finally, parents who participated were more likely to use a child car seat.

Abstract OT3-03-02: Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM)

Background: WISDOM is a 100,000 healthy women preference-tolerant, pragmatic study comparing traditional annual screening to personalized risk-based breast screening. The novelty of WISDOM personalized screening is the integration of previously validated genetic and clinical risk factors (age, family history, breast biopsy results, ethnicity, mammographic density) into a single risk assessment model that directs the starting age, timing, and frequency of screening. The goal of WISDOM is to determine if personalized screening, compared to annual screening, is as safe, less morbid, enables prevention, and is more accepted by women. The study is registered on ClinicalTrials.gov, NCT02620852.

Methods: Women aged 40-74 years with no history of breast cancer or DCIS, and no previous double mastectomy can join the study online at wisdomstudy.org. Participants can either elect randomization or self-select a study arm. Then, they can provide electronic consent and sign the Release for Medical Information via DocuSign. For all participants, 5-year risk of developing breast cancer is calculated according to the Breast Cancer Screening Consortium (BCSC) model. Participants in the personalized arm undergo panel-based mutation testing (BRCA1, BRCA2, TP53, PTEN, STK11, CDH1, ATM, PALB2, and CHEK2), and their 5-year risk is calculated using the BCSC score combined with a Polygenic Risk Score (BCSC-PRS) that includes 75 single nucleotide polymorphisms (SNPs) known to increase breast cancer risk (will increase to 229). The SNPs and mutations are assessed by saliva-based testing through Color Genomics. 5-year risk level thresholds are used to stratify for low-, moderate- and high risk. Risk stratification determines age to start, stop, and frequency of screening.

Accrual: As of July 2019, the WISDOM study is open to all eligible women in California, North Dakota, South Dakota, Minnesota, Iowa, Illinois, and New Jersey. To date, 30,392 eligible women have registered, and 21,392 women have consented to participate in the trial. The median age was 56 years. 85% of participants were Caucasian, 2% African-American, and 5% Asian. 6% self-reported Hispanic ethnicity. WISDOM is actively partnering with Blue Cross Blue Shield Association for national coverage, self-insured companies (Salesforce, Genentech, Qualcomm, CalPERS) and Medi-Cal (Inland Empire Health Plan) using a coverage with evidence progression approach.

Accrual expansion and diversity: To strengthen generalizability, the WISDOM Study is enhancing the diversity of our potential participant population by expanding to other states (Alabama, Louisiana), and partnering with other health insurers and self-insured companies. Future expansion regions include Texas, Florida, South Carolina, Oklahoma, Montana, and New Mexico. Additionally, we have translated the whole study experience to Spanish to further reach Spanish-speaking communities. With the engagement of patient advocates and community partnerships, expanding diversity recruitment will strengthen our scientific knowledge of breast cancer risk and increase access to personalized breast cancer screening recommendations for all women. WISDOM enrollment will continue through 2020.

Conclusions: Results at 5 years will enable us to demonstrate that personalized screening improves healthcare value by reducing screen volumes and costs without jeopardizing outcomes.

Citation Format: Mandy Che, Allison Stover Fiscallini, Irene Acerbi, Yiweh Shieh, Lisa Madlensky, Jeffrey Tice, Elad Ziv, Martin Eklund, Amie Blanco, Barry Tong, Deborah Goodman, Lamees Nassereddine, Nancy Anderson, Heather Harvey, Steele Fors, Hannah L Park, Antonia Petruse, Skye Stewart, Janet Wernisch, Larissa Risty, Ian Hurley, Barbara Koenig, Celia Kaplan, Robert Hiatt, Neil Wenger, Vivian Lee, Diane Heditsian, Susie Brain, Leah Sabacan, Barbara Parker, Alexander Borowsky, Hoda Anton-Culver, Hoda Anton-Culver, Arash Naeim, Andrea Kaster, Melinda Talley, Laura van't Veer, Andrea LaCroix, Olufunmilayo I Olopade, Deepa Sheth, WISDOM Study and Athena Breast Health Network Investigators and Advocate Partners and Laura Esserman. Personalized breast cancer screening in a population-based study: Women informed to screen depending on measures of risk (WISDOM) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-03-02.

Abstract OT2-08-01: Personalized breast cancer screening in a population based study: Women Informed to Screen Depending On Measures of risk (WISDOM)

Background: WISDOM is a 100,000 healthy women preference-tolerant, pragmatic study comparing annual to personalized risk-based breast screening. The novelty of WISDOM personalized screening is the integration of previously validated genetic and clinical risk factors (age, family history, breast biopsy results, ethnicity, mammographic density) into a single risk assessment model that directs the starting age, timing, and frequency of screening. The goal of WISDOM is to determine if personalized screening, compared to annual screening, is as safe, less morbid, enables prevention, and is preferred by women. The study is registered on ClinicalTrials.gov, NCT02620852.

Methods: Women aged 40-74 years with no history of breast cancer or DCIS, and no previous double mastectomy can join the study online at wisdomstudy.org. Participants can elect randomization or self-select a study arm, and provide electronic consent and Release for Medical Information using DocuSign. For all participants, 5-year risk of developing breast cancer is calculated according to the Breast Cancer Screening Consortium (BCSC) model. Participants in the personalized arm undergo panel-based mutation testing, and their 5-year risk is calculated using the BCSC score combined with a Polygenic Risk Score (BCSC-PRS) that includes 75 single nucleotide polymorphisms (SNPs, increase to 229) known to increase breast cancer risk. SNPs and mutations (BRCA1, BRCA2, TP53, PTEN, STK11, CDH1, ATM, PALB2, and CHEK2) are assessed by saliva-based testing through Color Genomics. 5-year risk level thresholds are used to stratify for low-, moderate- and high risk. Risk stratification determines age to start, stop, and frequency of screening.

Enrollment: As of July 2018, the WISDOM study is open to all eligible women in California, North Dakota, South Dakota, Minnesota and Iowa. To date, 23,329 eligible women have registered and 14,393 women have consented to participate in the trial. We analyzed 3,255 participants who have completed risk assessment in the personalized arm. The median age was 56 years. 82% were Caucasian, 1% African-American, and 6% Asian. 9% self-reported as Hispanic. We are partnering with health insurers and self-insured companies using coverage with evidence progression. To strengthen generalizability, we are expanding to other states. WISDOM enrollment will continue past 2019.

Feasibility: To evaluate the addition of PRS, we used paired statistical tests (McNemar) to compare the distributions of BCSC, and BCSC-PRS risk estimates around low-risk (<1.3%), and very-high risk (>6%) thresholds, the latter corresponding to 5-year risk of a BRCA mutation carrier. The median 5-year risk was 1.5% (IQR 1.0-2.1%) using the BCSC model, and 1.4% (IQR 0.8-2.5%) using the BCSC-PRS model. The BCSC-PRS model classified more women into the low (<1%) and very high (≥6%) risk categories compared to the BCSC model (p < 0.001).

Conclusions: Our findings demonstrate that incorporating genetic variants into a validated clinical model is feasible and impacts risk classification compared to a model without genetic risk factors. Results at 5 years will reveal if this classification improves healthcare value by reducing screen volumes and costs without jeopardizing outcomes.

Citation Format: Acerbi I, Shieh Y, Madlensky L, Tice J, Ziv E, Eklund M, Blanco A, DeRosa D, Tong B, Goodman D, Nassereddine L, Anderson N, Harvey H, Layton T, Park HL, Petruse A, Stewart S, Wernisch J, Risty L, Koenig B, Sarrafan S, Firouzian R, Kaplan C, Hiatt R, Parker BA, Wenger N, Lee V, Heditsian D, Brain S, Stover Fiscalini A, Borowsky AD, Anton-Culver H, Naeim A, Kaster A, Talley M, van 't Veer LJ, LaCroix A, Wisdom Study and Athena Breast Health Network Investigators and Advocate Partners, Esserman LJ. Personalized breast cancer screening in a population based study: Women Informed to Screen Depending On Measures of risk (WISDOM) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-08-01.

A physiologically relevant 3D collagen-based scaffold-neuroblastoma cell system exhibits chemosensitivity similar to orthotopic xenograft models

3D scaffold-based in vitro cell culturing is a recent technological advancement in cancer research bridging the gap between conventional 2D culture and in vivo tumours. The main challenge in treating neuroblastoma, a paediatric cancer of the sympathetic nervous system, is to combat tumour metastasis and resistance to multiple chemotherapeutic drugs. The aim of this study was to establish a physiologically relevant 3D neuroblastoma tissue-engineered system and explore its therapeutic relevance. Two neuroblastoma cell lines, chemotherapeutic sensitive Kelly and chemotherapeutic resistant KellyCis83 were cultured in a 3D in vitro model on two collagen-based scaffolds containing either glycosaminoglycan (Coll-GAG) or nanohydroxyapatite (Coll-nHA) and compared to 2D cell culture and an orthotopic murine model. Both neuroblastoma cell lines actively infiltrated the scaffolds and proliferated displaying >100-fold increased resistance to cisplatin treatment when compared to 2D cultures, exhibiting chemosensitivity similar to orthotopic xenograft in vivo models. This model demonstrated its applicability to validate miRNA-based gene delivery. The efficacy of liposomes bearing miRNA mimics uptake and gene knockdown was similar in both 2D and 3D in vitro culturing models highlighting the proof-of-principle for the applicability of 3D collagen-based scaffolds cell system for validation of miRNA function. Collectively, this data shows the successful development and characterisation of a physiologically relevant, scaffold-based 3D tissue-engineered neuroblastoma cell model, strongly supporting its value in the evaluation of chemotherapeutics, targeted therapies and investigation of neuroblastoma pathogenesis. While neuroblastoma is the specific disease being focused upon, the platform may have multi-functionality beyond this tumour type.

STATEMENT OF SIGNIFICANCE

Traditional 2D cell cultures do not completely capture the 3D architecture of cells and extracellular matrix contributing to a gap in our understanding of mammalian biology at the tissue level and may explain some of the discrepancies between in vitro and in vivo results. Here, we demonstrated the successful development and characterisation of a physiologically relevant, scaffold-based 3D tissue-engineered neuroblastoma cell model, strongly supporting its value in the evaluation of chemotherapeutics, targeted therapies and investigation of neuroblastoma pathogenesis. The ability to test drugs in this reproducible and controllable tissue-engineered model system will help reduce the attrition rate of the drug development process and lead to more effective and tailored therapies. Importantly, such 3D cell models help to reduce and replace animals for pre-clinical research addressing the principles of the 3Rs.

Explaining the accreditation process from the institutional isomorphism perspective: a case study of Jordanian primary healthcare centers

BACKGROUND

While the main focus of accreditation initiatives has been on hospitals, the implementation of these programs is a relatively new notion among other types of healthcare facilities. Correspondingly, this study aims to understand how accreditation is perceived among primary public healthcare centers using an isomorphic institutional theory.

DESIGN/METHODOLOGY

Semi-structured, in-depth interviews were conducted with 56 healthcare professionals and administrative staff from seven non-profit healthcare centers in Jordan using an explanatory case-study approach.

RESULTS

The informants' narratives revealed that all three components of institutional theory: coercive, mimetic, and normative pressure, were drivers for institutional change in seeking accreditation. There was an overlapping and blending between the three various types of pressure. While participants perceived that healthcare centers faced formal and informal pressures to achieve accreditation, health centers were reluctant about the time, amount of effort, and their ability to achieve the accreditation. Ambiguity and fear of failure forced them to model successful ones. Moreover, the findings revealed that normative values of health professionals enhanced institutional isomorphism and influenced the accreditation process.

CONCLUSION

Identifying these isomorphic changes may help key stakeholders to develop plans, policies, and procedures that could improve the quality of healthcare and enhance accreditation as an organizational strategic plan. Moreover, the study provided explanations of why and how organizations move to adopt new interventions and grow over time. Copyright © 2016 John Wiley & Sons, Ltd.

eEF-2 kinase is a critical regulator of Warburg effect through controlling PP2A-A synthesis

Cancer cells predominantly metabolize glucose by glycolysis to produce energy in order to meet their metabolic requirement, a phenomenon known as Warburg effect. Although Warburg effect is considered a peculiarity critical for survival and proliferation of cancer cells, the regulatory mechanisms behind this phenomenon remain incompletely understood. We report here that eukaryotic elongation factor-2 kinase (eEF-2K), a negative regulator of protein synthesis, has a critical role in promoting glycolysis in cancer cells. We showed that deficiency in eEF-2K significantly reduced the uptake of glucose and decreased the productions of lactate and adenosine triphosphate in tumor cells and in the Ras-transformed mouse embryonic fibroblasts. We further demonstrated that the promotive effect of eEF-2K on glycolysis resulted from the kinase-mediated restriction of synthesis of the protein phosphatase 2A-A (PP2A-A), a key factor that facilitates the ubiquitin-proteasomal degradation of c-Myc protein, as knockdown of eEF-2K expression led to a significant increase in PP2A-A protein synthesis and remarkable downregulation of c-Myc and pyruvate kinase M2 isoform, the key glycolytic enzyme transcriptionally activated by c-Myc. In addition, depletion of eEF-2K reduced the ability of the transformed cells to proliferate and enhanced the sensitivity of tumor cells to chemotherapy both in vitro and in vivo. These results, which uncover a role of the eEF-2K-mediated control of PP2A-A in tumor cell glycolysis, provide new insights into the regulation of the Warburg effect.

Abstract P2-16-05: Efficacy of ABT-888 (veliparib) in patients with BRCA-associated breast cancer

Background: The potential for exploiting BRCA deficiencies with DNA repair inhibitors has both pre-clinical and clinical support. ABT-888 (veliparib), a DNA repair inhibitor initially thought to target Poly(ADP-Ribose) Polymerases (PARP), has demonstrated in vitro inhibition of BRCA1 and BRCA2 deficient mouse embryonic stell cells, with a larger effect on BRCA1 cells. We report on the pre-planned interim analysis of the efficacy of single agent veliparib in patients with either BRCA1 or BRCA2-associated stage IV breast cancer. Methods: BRCA 1 or 2 carrier patients with stage IV breast cancer, with measurable disease, without prior exposure to a PARP inhibitor or a platinum compound in the metastatic setting, were eligible. Velapirib was administered orally, at doses of 400 mg twice daily. Dose adjustments based on toxicity were permitted. Patients progressing on velapirib alone received carboplatin at an AUC of 5, IV, given Q 21 days, and velapirib 150 mg twice daily (the maximum tolerated dose [MTD] of the combination from our completed Phase I study: J Clin Oncol 30, 2012 [suppl; abstr 1024]). Patients were to be accrued from 7 NCI NO1- supported consortia. Initially 10 patients were to be accrued to each stratum (BRCA1 and BRCA2) to provide evidence of single agent activity. If there was sufficient activity to warrant consideration of velapirib as single agent therapy (defined as 2 or more confirmed partial [PR] or better responses out of 10 per stratum), an additional 12 patients would be accrued per stratum. Results: 20 evaluable patients (11 BRCA1 and 9 BRCA2 [1 in screening]) have been accrued, the majority with lung or liver as visceral metastatic sites of disease. Median age (range) is 46 (29-68) years. Tumors from 9 patients were hormone receptor positive. BRCA1 cohort: 4 of 11 patients are off treatment at a median of 2 months (1-4); 1 patient stopped velapirib due to toxicity (grade 2 rash/pruritus, grade 2 vomiting), 3 stopped for progressive disease (one with an unconfirmed PR). Seven patients are still on single agent veliparib with 1 unconfirmed PR, and 1 patient with two evaluations showing stable disease. BRCA2 cohort: 2 patients are off treatment at 2 months for progressive disease, 7 are still on treatment with 1 confirmed PR, and 3 unconfirmed PRs. Data on patients receiving combination of velapirib and carboplatin after progression is too early. Treatment-related toxicity is being updated and has so far been reported from 14 patients: 1 patient had grade 3 fatigue, 1 patient with liver metastasis had both grade 3 alanine aminotransferase elevation and grade 3 abdominal pain. Grade 2 toxicities occurring in more than 1 patient included nausea/vomiting (6 patients), chills (2 patients), and fatigue (2 patients). Conclusion: Velapirib has single agent activity in both BRCA1 and BRCA2-associated stage IV breast cancer patients, and is well-tolerated. Mature response, treatment, and toxicity data will be presented.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-05.

PilM/N/O/P proteins form an inner membrane complex that affects the stability of the Pseudomonas aeruginosa type IV pilus secretin

The highly conserved pilM/N/O/P/Q gene cluster is among the core set of genes required for cell surface expression of type IV pili and associated twitching motility. With the exception of the outer membrane secretin, a multimer of PilQ subunits, the specific functions of the products encoded by this gene cluster are poorly characterized. Orthologous proteins in the related bacterial type II secretion system have been shown to interact to form an inner membrane complex required for protein secretion. In this study, we provide evidence that the PilM/N/O/P proteins form a functionally equivalent type IVa pilus complex. Using Pseudomonas aeruginosa as model organism, we found that all four proteins, including the nominally cytoplasmic PilM, colocalized to the inner membrane. Stability studies via Western blot analyses revealed that loss of one component has a negative impact on the levels of other members of the putative complex. Furthermore, complementation studies revealed that the stoichiometry of the components is important for the correct formation of a stable complex in vivo. We provide evidence that an intact inner membrane complex is required for optimal formation of the outer membrane complex of the type IVa pilus system in P. aeruginosa, as PilQ stability is negatively affected in its absence. Finally, we show that, in the absence of the pilin subunit, the levels of membrane-bound components of the inner membrane complex are negatively regulated by the PilR/S two-component system, suggesting a role for PilR/S in sensing the piliation status of the cell.

Incidence of peripheral neuropathy in high-risk early-stage breast cancer patients receiving dose-dense paclitaxel in central Pennsylvania

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Background: Paclitaxel (P) is an important part of chemotherapy regimens for early breast cancer. Breast cancer survivors may be left with iaotrogenic peripheral neuropathy which can affect their quality of life. Methods: We conducted a retrospective, IRB approved, medical chart review to determine the rate of peripheral neuropathy in a tertiary care practice in central Pennsylvania. Patients had biopsy proven, newly diagnosed, high risk breast cancer. Patients were treated with a standard dose dense (DD) regimen where 4 cycles of adriamycin (A) 60 mg/m2/cyclophosphamide (C) 600 mg/m2 were followed by four cycles of paclitaxel (P) 175 mg/m2 every 2 weeks (Citron et al) between 7/2006 to7/2008 at Penn State Cancer Institute. All patients who received dose dense chemotherapy by a single provider were included (n=23). No peripheral neuropathy (PN) was reported before initiating paclitaxel, but 3 of 23 patients had type II diabetes. Electronic medical charts were reviewed and data was abstracted to analyze incidence of peripheral neuropathy. These data were compared to reported published data. Results: 22 pts received dose dense AC followed by P chemotherapy. 100% completed 4 cycles of AC and 87% complete 4 cycles of P. Overall, 82% developed neuropathy (32% with grade 1, 41 % with grade 2, 9 % with grade 3). Almost 30% of patients required gabapentin for control of neuropathic pain. 35% of patients with PN had symptoms persisting >3 months after chemotherapy. Conclusions: A considerable percentage of high risk, early breast cancer patients treated with AC followed by DD paclitaxel developed at least mild neurotoxicity. Rates of Grade 3 neurotoxicity were much higher (9%) than the previous CALGB-9741 study (4%). This may be related to regional pharmacogenomic differences. Although dense dose paclitaxel has been shown to improve disease free survival, PN affects most patients treated with paclitaxel and for some patients can have a prolonged impact on their quality of life. Future studies should attempt identify which patients are at risk for severe peripheral neuropathy.

No significant financial relationships to disclose.

Constructs of health and environment inform child obesity prevention in American Indian communities

OBJECTIVE

Obesity prevention efforts have had limited success in American Indian (AI) populations. More effective prevention programs might be designed using insights into linkages between parental health beliefs, environmental constraints and healthy lifestyle choices.

METHODS AND PROCEDURES

Focus group sessions (n = 42 participants) were conducted to explore parental perspectives on children's health, diet and physical activity in three Wisconsin Tribal communities. Focus group questions were derived from preliminary interviews and observations on environmental barriers surrounding nutrition and physical activity.

RESULTS

Two broad thematic areas emerged from the focus groups: child health themes and environmental themes. Health themes included views of child health (emphasizing emotional health), views on parenting, and assessment of risks to child safety. Environmental (social and physical) themes included assessments of personal support networks, assessments of local facilities and programs, and values regarding household relationships. A provisional model of family behaviors related to child nutrition and physical activity was developed to better understand these themes and the potential tensions among them.

DISCUSSION

Understanding the unique cultural constructs of health and environment of AI communities can inform decision making in community-level prevention research. The proposed model served as a useful starting point for designing healthy lifestyle interventions in these AI communities. This model may also be applicable to other minority communities.

The arm as a skin graft donor site in eyelid reconstruction

PURPOSE

To report the technique, success, and complications of using the arm as a donor site for full-thickness skin grafts used in eyelid and facial reconstruction.

METHODS

The charts of 42 patients were reviewed. The arm was used as a donor site for harvesting full-thickness skin grafts in 52 procedures of eyelid or facial reconstruction.

RESULTS

The size of skin grafts varied from 4.0 cm2 to 59.5 cm2. There were few recipient site complications: partial necrosis (n=2), severe contraction (n=2), and hair growth (n=4). Donor site complications included wound dehiscence (n=2) and hypertrophic scarring (n=2).

CONCLUSIONS

The arm is an acceptable donor site for harvesting full-thickness skin grafts for use in eyelid and facial reconstruction when either traditional donor sites are unavailable or a large amount of skin is needed.

Safety and efficacy of bisphosphonates beyond 24 months in cancer patients

PURPOSE

Bisphosphonate therapy has decreased the risk of skeletal complications associated with osteolytic bone lesions in patients with breast cancer and multiple myeloma. The large prospective studies have used 21 to 24 months of treatment. We studied the safety and efficacy of bisphosphonates in a subset of patients who received therapy for more than 24 months.

PATIENTS AND METHODS

Patients who received bisphosphonates (pamidronate or zoledronic acid) were identified. Data on skeletal events and laboratory parameters were gathered by chart review.

RESULTS

We studied 22 patients who received intravenous pamidronate or zoledronic acid for a duration of 3.6 years (range, 2.2 to 6.0 years). Prolonged therapy was well tolerated. No significant calcium, phosphorus, electrolyte, or WBC count abnormalities were encountered. There was a clinically insignificant decrease in hemoglobin and platelet count and an increase in creatinine in these patients. The fracture rate beyond 2 years was no greater than during the first 2 years of treatment. There were no stress fractures of long bones with prolonged therapy.

CONCLUSION

Prolonged treatment with the potent bisphosphonates pamidronate and zoledronic acid seems to be well tolerated and should be studied in prospective, randomized studies to document prolonged skeletal efficacy.

What did we learn about interdisciplinary collaboration in institutions?

The Interdisciplinary Generalist Curriculum (IGC) Project significantly advanced collaboration in the development of medical school curricula. As primary care faculty began to work together they encountered and overcame many challenges inherent in this new process. Inclusion of other faculty and departments, as well as dedicated support from the deans' offices, became necessary to the success of the projects. The continuation of successful collaborative projects in the medical school environment requires a common commitment of faculty, students, department chairs, and the dean's office; protected time; and involvement of faculty from other disciplines. This article outlines initial models of collaboration implemented in the IGC Project, followed by a description of the expected and unexpected outcomes of these collaborative efforts, and a discussion of the emergence of new ways of collaborating, with recommendations for successful collaborative efforts.

The Interdisciplinary Generalist Curriculum Project at Joan C. Edwards School of Medicine at Marshall University

The Interdisciplinary Generalist Curriculum (IGC) Project was designed to enhance interest in and support of generalism during the first two years of medical education. The original goals at Joan C. Edwards School of Medicine at Marshall University included the design and implementation of a core curriculum, Introduction to Patient Care (IPC), and enhancement of teaching excellence through faculty development. The core curriculum facilitated integration with the basic sciences and early introduction of physical examination skills, which were further developed in longitudinal clinical experiences with mentors. Although it was not originally intended to include basic scientists in the preceptor groups, they became important additions and created additional opportunities for interdisciplinary teaching and reciprocal learning. The mentor program, another well-received and intended curriculum change, evolved from a structured experience to a more flexible component of the curriculum. The program met the requirements of the IGC Project but 53% of the originally intended mentor time was achievable, due to curriculum constraints. Faculty development, another success, was originally intended to target IPC faculty but ultimately became a university-wide effort. The changes implemented as a result of the IGC Project continue to flourish beyond the funding period and have become integral aspects of the curriculum and the medical school.

A phase I dose-ranging trial of monthly infusions of zoledronic acid for the treatment of osteolytic bone metastases

Bisphosphonates are potent inhibitors of bone resorption and provide a therapeutic benefit for patients with bone metastases. Zoledronic acid is a highly potent, nitrogen-containing bisphosphonate. In the present trial, we assessed the safety and tolerability of increasing doses of zoledronic acid and its effects on urinary markers of bone resorption in cancer patients with bone metastases. Fifty-nine cancer patients with bone metastases were enrolled sequentially into one of 8 treatment groups in the core protocol. Each patient received a 5-min i.v. infusion of 0.1, 0.2, 0.4, 0.8, 1.5, 2, 4, or 8 mg zoledronic acid monthly for 3 months. Patients were monitored for clinical findings, adverse events, electrocardiograms, markers of bone resorption, as well as routine hematology, blood chemistries, and urinalysis. Thirty patients who demonstrated a radiographic response to treatment or stable disease in the core protocol were enrolled in a humanitarian extension protocol and continued to receive monthly infusions. Zoledronic acid was well tolerated at all dose levels. Adverse events reported by >10% of patients included skeletal pain, nausea, fatigue, upper respiratory tract infection, constipation, headache, diarrhea, and fever. Three patients in the core protocol and one patient in the extension protocol experienced grade 3 skeletal pain, "flu-like" symptoms, or hypophosphatemia, which were possibly related to treatment; all recovered completely. Adverse events were reported with similar frequency across all of the dosage groups. Zoledronic acid resulted in sustained, dose-dependent decreases in urinary markers of bone resorption. Zoledronic acid was safe and well tolerated and demonstrated potent inhibition of bone resorption.

Wrestling with typology: penetrating the "black box" of managed care by focusing on health care system characteristics

The health care system has undergone a fundamental transformation undermining the usefulness of the typology of the health maintenance organization, the independent practice association, the preferred provider organization, and so forth. The authors present a new approach to studying the health care system. In matrix form, they have identified a set of organizational and delivery characteristics with the potential to influence outcomes of interest, such as access to services, quality, health status and functioning, and cost. The matrix groups the characteristics by domain--financial features, structure, care delivery and management policies, and products--and by key roles in the health care system--sponsor, plan, provider intermediary organization, and direct services provider. The matrix is a tool for researchers, administrators, clinicians, data collectors, regulators, and other policy makers. It suggests a new set of players to be studied, emphasizes the relationships among the players, and provides a checklist of independent, control, and interactive variables to be included in analyses.

Overexpression of HER2 modulates bcl-2, bcl-XL, and tamoxifen-induced apoptosis in human MCF-7 breast cancer cells

Overexpression of HER2 in estrogen receptor (ER)-positive human breast tumors has been associated with resistance to endocrine therapy. Here we investigated the effects of HER2 on expression of apoptotic pathways and modulation of tamoxifen-induced apoptosis in ER-positive MCF-7 breast cancer cells. We report that HER2 overexpression in MCF-7 cells is accompanied by up-regulation of antiapoptotic Bcl-2 and Bcl-XL proteins and suppression of tamoxifen-induced apoptosis. In addition, human tumor cell lines that are both ER positive and overexpress HER2 also express enhanced levels of Bcl-2 compared to cells that are either ER positive or overexpress HER2 alone. Our findings suggest that possible deregulation of antiapoptotic Bcl-2 and Bcl-XL may be associated with the enhanced survival of HER2-overexpressing and ER-positive breast cancer cells treated with antiestrogens.

Intravenous vinorelbine as first-line and second-line therapy in advanced breast cancer

PURPOSE

We evaluated single-agent intravenous (IV) vinorelbine as first- and second-line treatment for advanced breast cancer (ABC) in patients who were not resistant to anthracyclines. Objective tumor response (TR) and toxicity were assessed.

PATIENTS AND METHODS

A total of 107 women were enrolled onto this multicenter, nonrandomized, open-label phase II study. Patients were stratified into first- and second-line treatment groups, based on prior treatment history. Vinorelbine was initially given at 30 mg/m2/wk, with dose modification for toxicity as indicated. Therapy was continued until disease progression or severe toxicity mandated withdrawal or until the patient asked to be removed from the study.

RESULTS

The objective response rate for all patients was 34% (95% confidence interval [CI], 25% to 44%): 35% (95% CI, 23% to 48%) for first-line patients and 32% (95% CI, 20% to 47%) for second-line patients. Nine first-line and three second-line patients obtained a complete response (CR). The median duration of objective response was 34 weeks in both groups. The overall survival durations of first- and second-line patients were 67 weeks and 62 weeks, respectively. Granulocytopenia was the predominant dose-limiting toxicity. Two patients died on study as a result of granulocytopenic sepsis.

CONCLUSION

Single-agent vinorelbine is an effective and well-tolerated agent for first- and second-line therapy of ABC. The results of this study confirm the findings of similar international trials and suggest vinorelbine should be considered a valid treatment option for patients with ABC and a potential component in future combination regimens for this disease.

A unifying hypothesis that links benign prostatic hyperplasia and prostatic intraepithelial neoplasia with prostate cancer. Invited comments

Prostatic Intraepithelial Neoplasia (PIN) and prostatic cancer (PCA) are not caused by infection, allergic reaction, inadequate immunological response, ischemia, ageing, systemic hormones, carcinogens, nor prostatic ductal contents. PIN and PCA are apparently caused by increased inner acinar pressure due to partially blocked draining ducts. Only this explanation can account for all the observations about PIN and PCA. All other possible causes are disproved by specific observations. In order to further clarify the cause of PIN and PCA, it is important to discover if peripheral zone lesions cluster around ducts or blood vessels. PIN patterns are the morphological precursors of both PCA and prostatic cysts. Different PIN patterns represent different adaptive stages to increasing inner acinar pressure. The immediate tissue cause of PCA is PIN disruption seeding the stroma with high-grade PIN (HGPIN) cells. These cells, programmed for adaptive proliferation and mobility in PIN, are sufficient in the stroma to cause all stages and patterns of invasive PCA. No mutated cells are necessary. For reasons given, the primary cause of the initial ductal blockage that results in PIN and PCA cannot be inflammation, stones, proteineous plugs, infarction, venus thrombosis, ductal hyperplasia, nor a constricted penis at ejaculation. Only benign prostatic hyperplasia (BPH) can explain all the facts and is thus the primary cause of the ductal blockage resulting in cysts, PIN and PCA. The main causes of BPH are apparently disuse atrophy of sexual and abdominal muscles, and atherosclerosis of the capsular branch of the prostatic artery, causes atypical adenomatous hyperplasia (AAH) in the transition zone. The resulting muscular and glandular atrophy decreases local and general growth inhibitors. New growth in the adult prostate is abnormal because epithelial cells grow into ducts rather into the stroma. In such ducts, the growths cannot receive stromal growth inhibitory signals, and thus continue to grow indefinitely and result in BPH, AAH-adenosis, blockage of ducts, cysts, PIN and PCA.

Elevated serum c-erbB-2 antigen levels and decreased response to hormone therapy of breast cancer

PURPOSE

Decisions concerning the use of hormone therapy to treat metastatic breast cancer are made on the basis of the presence of estrogen receptor (ER). Despite the presence of ER, half of patients will not respond to hormone treatment. The purpose of this study was to determine the effect of overexpression of HER-2/neu on the response to hormone therapy.

PATIENTS AND METHODS

Sera from 300 metastatic breast cancer patients with ER-positive (ER+), ER status unknown, or ER-/progesterone receptor-positive (PR+) randomized to receive second-line hormone therapy with either megestrol acetate or fadrozole were evaluated. An enzyme immunoassay (EIA) specific for the extracellular domain of the c-erbB-2 (HER-2/neu) oncogene product was used to detect serum levels.

RESULTS

Fifty-eight patients (19.3%) had elevated serum c-erbB-2 protein levels, using a selected cut-point of 30 U/mL. The response rate (complete responses [CRs] plus partial responses [PRs] plus stable disease [S]) to endocrine therapy was 40.9% in 242 patients with low serum c-erbB-2 levels and only 20.7% in 58 patients with elevated serum c-erbB-2 levels (P = .004). The median duration of treatment response was longer in the group with low serum c-erbB-2 levels (15.5 months) compared with the group with elevated serum c-erbB-2 levels (11.6 months). Survival was also significantly shorter in patients with elevated serum c-erbB-2 levels (P < .0001).

CONCLUSION

Patients with ER+/c-erbB-2+ metastatic breast cancer are less likely to respond to hormone treatment than ER+/c-erbB-2- patients. Their survival duration is also shorter.

Aromatase inhibitor development for treatment of breast cancer

Inhibition of estrogen production provides effective therapy for patients with hormone-dependent breast cancer. The source of estrogens in premenopausal women is predominantly the ovary, but after the menopause, estradiol is synthesized in peripheral tissues through the aromatization of androgens to estrogens. Uptake from plasma is the primary mechanism for maintenance of estradiol concentrations in breast cancer tissue in premenopausal women, whereas several steps may be operant in postmenopausal women. These include enzymatic synthesis of estradiol via sulfatase, aromatase, and 17 beta-hydroxysteroid dehydrogenase in the tumor itself. Aromatization of androgens secreted by the adrenal to estrogens in peripheral tissues and transport to the tumor via circulation in the plasma provides another means of maintaining breast tumor estradiol levels in postmenopausal women. These various sources contribute to the high tissue estrogen levels measured in breast tumor tissue. To effectively suppress tissue concentrations of estrogens and circulating estradiol in postmenopausal patients, various aromatase inhibitors have been developed recently. These include steroidal inhibitors such as 4-hydroxy-androstenedione as well as non-steroidal compounds with imidazole and triazole structures. The most potent of these, CGS 20267, is reported to suppress levels of active estrogens (i.e., estrone, estrone sulfatase, and estradiol) by more than 95%. This compound can suppress both serum and 24-hr urine estrogens to a greater extent than produced by the second generation inhibitor, CGS 16949A. CGS 20267 is highly specific since it does not affect cortisol and aldosterone serum levels during ACTH stimulation tests nor sodium and potassium balance in 24-hr urine samples.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased urinary excretion of pyridinium cross-links in cancer patients

Pyridinoline (PYD) and deoxypyridinoline (DPD), two collagen-based cross-links found in bone, were measured by high-performance liquid chromatography in urine samples from 65 control subjects and 97 patients with either untreated or progressive cancer. Patients with cancer had significantly (P < 0.001) higher urine concentrations of PYD and DPD than did control subjects. Both cross-links were increased in cancer patients with and without clinically detectable bone metastases, although patients with bone and liver involvement had higher mean concentrations. The mean concentrations of both cross-links were also significantly higher in the urine samples of inpatients than in an outpatient ambulatory population. These findings suggest that the measurement of PYD and DPD in urine may be useful in assessing bone metastases and bone resorption in cancer patients.

Increased urinary excretion of pyridinium cross-links in cancer patients

Pyridinoline (PYD) and deoxypyridinoline (DPD), two collagen-based cross-links found in bone, were measured by high-performance liquid chromatography in urine samples from 65 control subjects and 97 patients with either untreated or progressive cancer. Patients with cancer had significantly (P &lt; 0.001) higher urine concentrations of PYD and DPD than did control subjects. Both cross-links were increased in cancer patients with and without clinically detectable bone metastases, although patients with bone and liver involvement had higher mean concentrations. The mean concentrations of both cross-links were also significantly higher in the urine samples of inpatients than in an outpatient ambulatory population. These findings suggest that the measurement of PYD and DPD in urine may be useful in assessing bone metastases and bone resorption in cancer patients.

Interleukin-2 and interferon-alpha-2a outpatient therapy for metastatic renal cell carcinoma

The combination of interleukin-2 (IL-2) and interferon-alpha-2a (IFN-alpha-2a) has synergistic bioactivity in numerous preclinical model systems. Thirty-nine patients with metastatic renal cell cancer were treated with continuous intravenous infusion IL-2 for 4-5 days plus intramuscular IFN-alpha-2a 2-3 days a week for 4 consecutive weeks. A 2- to 4-week rest period was permitted after each 4 weeks of treatment. Thirty-one of the 39 patients were assessable for response determination. Response rate (six complete+seven partial remissions) was 33.3% for all patients, or 41.9% when the analysis was restricted to the 31 evaluable patients. Three patients were unable to tolerate treatment due to anorexia, weight loss, and severe fatigue. This therapy was relatively well tolerated in the outpatient setting in the other patients despite fever, chills, fatigue, anorexia, and weight loss. There was no correlation of response with site of metastases or bulk of disease.

Hormonal and immunological regulation of 2', 5'-oligoadenylate synthetase activity in human peripheral blood mononuclear cells

A newly developed method for assaying 2', 5'-oligoadenylate (2, 5A) synthetase activity by polyacrylamide gel electrophoresis was applied to peripheral blood mononuclear cells (PBMC) from normal subjects, HIV-positive subjects, and renal cell carcinoma (RCC) patients. Sex differences were observed in 2, 5A synthetase activity of PBMC from normal young adults, males having eightfold higher activities of this enzyme than females. Moreover, compared to values for postmenopausal (PM) females receiving estrogen replacement, untreated PM females had higher activities. Collectively, these results suggest that estrogen downregulates 2, 5A synthetase activity. Activities of 2, 5A synthetase were investigated in two disease states associated with altered immune function. In one patient with AIDS-related Kaposi's sarcoma, interferon-alpha (IFN-alpha) therapy increased 2, 5A synthetase activity twofold. In addition, combined therapy with interleukin-2 (IL-2) and IFN-alpha increased 2, 5A synthetase activities in eight of nine patients with RCC. Therefore, in patients receiving immunotherapy with IL-2 and IFN-alpha, our new assay could contribute to evaluation of immune stimulation. In general, studies in vitro confirmed these observations; however, exposure of PBMC from RCC patients revealed that in vitro IL-2 failed to induce this enzyme activity as it did in PBMC from normal volunteers.