Dealing with digital paralysis: Surviving a cyberattack in a National Cancer center

INTRODUCTION

Cyberattacks represent a growing threat for healthcare delivery globally. We assess the impact and implications of a cyberattack on a cancer center in Ireland.

METHODS

On May 14th 2021 (day 0) Cork University Hospital (CUH) Cancer Center was involved in the first national healthcare ransomware attack in Ireland. Contingency plans were only present in laboratory services who had previously experienced information technology (IT) failures. No hospital cyberattack emergency plan was in place. Departmental logs of activity for 120 days after the attack were reviewed and compared with historical activity records. Daily sample deficits (routine daily number of samples analyzed - number of samples analyzed during cyberattack) were calculated. Categorical variables are reported as median and range. Qualitative data were collected via reflective essays and interviews with key stakeholders from affected departments in CUH.

RESULTS

On day 0, all IT systems were shut down. Radiotherapy (RT) treatment and cancer surgeries stopped, outpatient activity fell by 50%. hematology, biochemistry and radiology capacity fell by 90% (daily sample deficit (DSD) 2700 samples), 75% (DSD 2250 samples), and 90% (100% mammography/PET scan) respectively. Histopathology reporting times doubled (7 to 15 days). Radiotherapy (RT) was interrupted for 113 patients in CUH. The median treatment gap duration was six days for category 1 patients and 10 for the remaining patients. Partner organizations paused all IT links with CUH. Outsourcing of radiology and radiotherapy commenced, alternative communication networks and national conference calls in RT and Clinical Trials were established. By day 28 Email communication was restored. By day 210 reporting and data storage backlogs were cleared and over 2000 computers were checked/replaced.

CONCLUSION

Cyberattacks have rapid, profound and protracted impacts. While laboratory and diagnostic deficits were readily quantified, the impact of disrupted/delayed care on patient outcomes is less readily quantifiable. Cyberawareness and cyberattack plans need to be embedded in healthcare.

POLICY SUMMARY

Cyberattacks pose significant challenges for healthcare systems, impacting patient care, clinical outcomes, and staff wellbeing. This study provides a comprehensive review of the impact of the Conti ransomware attack on cancer services in Cork University Hospital (CUH), the first cyberattack on a national health service. Our study highlights the widespread disruption caused by a cyberattack including shutdown of information technology (IT) services, marked reduction in outpatient activity, temporary cessation of essential services such as radiation therapy. We provide a framework for other institutions for mitigating the impact of a cyberattack, underscoring the need for a cyberpreparedness plan similar to those made for natural disasters and the profound legacy of a cyberattack on patient care.

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.

Clinical boundaries in adult cases of large B cell lymphoma with IRF4 rearrangement

AIMS

Large B-cell lymphoma with IRF4 rearrangement (LBCL-IRF4) is a recently described entity included in the revised 4th edition of the WHO Classification of Haematolymphoid Tumours (2017). Here we highlight the difficulties in classification of those cases which arise in adult patients with unusual clinical features.

RESULTS

We present three cases with morphological and immunohistochemical features consistent with large B-cell lymphoma arising in adult patients, which were found to have isolated IRF4 rearrangements on FISH analysis. Each patient presented with advanced-stage disease and had a history of immunosuppression; clinical features that are not typical of LBCL-IRF4 and which make the distinction from DLBCL, not otherwise specified (NOS) challenging.

CONCLUSION

We propose that the clinical boundaries of LBCL-IRF4 arising in adult patients need further delineation to allow distinction from true cases of DLBCL, NOS.

The Impact of a National Cyberattack Affecting Clinical Trials: The Cancer Trials Ireland Experience

PURPOSE

Cyberattacks are increasing in health care and cause immediate disruption to patient care, have a lasting impact, and compromise scientific integrity of affected clinical trials. On the May 14, 2021, the Irish health service was the victim of a nationwide ransomware attack. Patient care was disrupted across 4,000 locations, including 18 cancer clinical trials units associated with Cancer Trials Ireland (CTI). This report analyses the impact of the cyberattack on the organization and proposes steps to mitigate the impact of future cyberattacks.

METHODS

A questionnaire was distributed to the units within the CTI group; this examined key performance indicators for a period of 4 weeks before, during, and after the attack, and was supplemented by minutes of weekly conference call with CTI units to facilitate information sharing, accelerate mitigation, and support affected units. A total of 10 responses were returned, from three private and seven public hospitals.

RESULTS

The effect of the attack on referrals and enrollment to trials was marked, resulting in a drop of 85% in referrals and 55% in recruitment before recovery. Radiology, radiotherapy, and laboratory systems are heavily reliant on information technology systems. Access to all was affected. Lack of preparedness was highlighted as a significant issue. Of the sites surveyed, two had a preparedness plan in place before the attack, both of these being private institutions. Of the eight institutions where no plan was in place, three now have or are putting a plan in place, whereas no plan is in place at the five remaining sites.

CONCLUSION

The cyberattack had a dramatic and sustained impact on trial conduct and accrual. Increased cybermaturity needs to be embedded in clinical trial logistics and the units conducting them.

A pilot project investigating the use of ONCOpatient®-An electronic patient-reported outcomes app for oncology patients

Purpose

To investigate the feasibility of implementing a remote patient monitoring system using an electronic patient-reported outcomes (ePROs) platform in a tertiary cancer center in the Republic of Ireland.

Methods

Patients receiving oral chemotherapy and oncology clinicians were invited to participate in the study. Patients were asked to submit weekly symptom questionnaires through an ePRO mobile phone application (app)-ONCOpatient®. Clinical staff were invited to use the ONCOpatient® clinician interface. After 8 weeks all participants submitted evaluation questionnaires.

Results

Thirteen patients and five staff were enrolled in the study. The majority of patients were female (85%) with a median age of 48 years (range 22-73). Most (92%) were enrolled over telephone requiring on average 16 minutes. Compliance with the weekly assessments was 91%. Alerts were triggered by 40% of patients who then required phone calls to aid with symptom management. At the end of study, 87% of patients reported they would use the app frequently, 75% reported that the platform met their expectations, and 25% that it exceeded their expectations. Similarly, 100% of staff reported they would use the app frequently, 60% reported that it met their expectations, and 40% that it exceeded their expectations.

Conclusions

Our pilot study showed that it is feasible to implement ePRO platforms in the Irish clinical setting. Small sample bias was recognized as a limitation, and we plan to confirm our findings on a larger cohort of patients. In the next phase we will integrate wearables including remote blood pressure monitoring.

Impact of Conti ransomware attack on cancer trials Ireland sites

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Background: Cancer trials in Ireland are conducted in both public Health Service Executive (HSE) and private hospitals and are overseen by Cancer Trials Ireland (CTI). On the 14th of May 2021 the Irish National HSE was the victim of a “Conti” ransomware attack. The attack triggered a “Critical Incident Process,” and the shutting down of all HSE IT systems at a national level. Disruption to patient care across the HSE’s 4000 locations, 54 acute hospitals, and 70,000 connected devices was drastic, immediate and without warning. Methods: The purpose of this study is to quantify the impact of the attack on the clinical trials network. A questionnaire was distributed by CTI to the 16 trials units within the group, this examined patient referrals and key performance indexes for a period of 4 weeks; prior, during, and after the attack. A total of 10 responses were returned, with a split of 3 private and 7 HSE hospitals. Results: The effect of the attack on referrals and enrollment to clinical trials was marked. In the 4 weeks prior to the attack 273 patients in total were referred to the trials units for screening, this fell to 41 patients in the 4 weeks during and recovering to 323, 4 weeks after. 49 patients were enrolled in trials prior the attack, 22 during and 38 after, a drop of 85% in referrals and 55% in recruitment to trials before recovery. Radiotherapy delivery was interrupted for patients on treatment or delayed for those initiating it. Radiology, lab systems and radiotherapy are heavily reliant on IT systems. Access to all was impacted, with only urgent diagnostic tests being carried out. Requesting tests and reports pivoted to a paper based systems. With staff having to present in person to request and collect reports. Patient safety was prioritized, with accurate paper records and logs in lieu of electronic records. Scientific integrity of trials involving combined modality or radiotherapy was compromised in HSE hospitals. No change in adverse outcomes was reported across all units surveyed before, during and after the attack. Normal access to emails in sites that were impacted ranged from days at a minimum to 6 weeks in the worst affected centers. Normal access to radiology and lab tests took on average 26 and 32 days respectively. Conclusions: A significant issue highlighted by the cyber-attack was the lack of redundancy in the IT systems used throughout Irish hospitals on a daily basis and a lack of a plan when these systems fail. Of the 10 sites surveyed, 2 had a preparedness plan in place prior to the attack, both of these private institutions. Of the 8 institutions where no plan was in place only 3 now have or are putting a plan in place, no plan is in place in the 5 remaining sites. At this time one HSE hospital has been subject to a repeat ransomware attack and patient data from another has been released on the dark web. Reviewing the impact of the cyber attack on CTI highlights the usefulness of preparedness, with units that had a plan in place prior to the attack least affected overall.

The impact of a ransomware cyber attack on a breast cancer center

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Background: On the 14th of May 2021 the Irish Health Service Executive (HSE) was the victim of a “Conti” ransomware attack. The HSE is a nationwide organization providing Ireland’s public health service, consisting of approximately 4000 locations and more than 70,000 connected devices. The study aim is to quantify the impact of the cyber attack by examining the effect on the Breast Cancer services at Cork University Hospital 1 of 8 national cancer centres & 1 of 54 HSE acute hospitals. Methods: New patient referrals through the weekly Breast cancer MDT meeting were used as the study nidus. Patient referrals & key performance indexes for a period of 4 weeks prior, during & after the attack were examined. Time was the key metric examined. Results: The attack triggered a Critical Incident Protocol, resulting in the switching off of all HSE IT systems at national level. Disruption to patient care & operations within the HSE was immediate & without warning. Initially encrypted messaging groups were established to facilitate communication & paper based tracking & data management logs were created. Diagnostics, scheduling & radiotherapy services were most severely affected. The attack resulted in the immediate shut down of the hospitals radiotherapy department with all new treatments transferred off site to a private facility, ongoing treatments delayed, replanned or rescheduled. The effect on the radiology department was catastrophic, all outpatient & non-urgent scans were cancelled. Digital report & image stores were unavailable. Historic imaging & ongoing emergency imaging was unavailable. Taking 7 months to restore impacted data storage & to ensure accurate capture of all reports for examinations during the cyber downtime. The average time from surgery to completed pathology went from 7.04 to 15.03 & 11.8 days in the 4 weeks prior, during & after the attack respectively. Services that were least impacted during the IT outage were those that relied on paper records including chemotherapy administration. The average time from biopsy report to up front surgery decreased from 21.75 to 17 & 14 days in the 4 weeks prior, during & after the attack respectively. Likely due to the increased availability of theatre time, as all non cancer related elective procedures were cancelled. There was little effect on the time from MDT discussion to review by medical oncology, taking an average of 6, 5.7 & 5.8 days in the 4 weeks prior, during & after the attack respectively. The majority of new referrals to the service being seen off site in a satellite clinic & infusion unit that relied on a paper based booking system prior to the attack. Conclusions: The cyber attack had significant disruptive effects lasting months. The impact on patient outcome due to delayed or interrupted treatment will take years to clarify. The attack was facilitated by the presence of multiple, fragmented IT platforms & demonstrated a lack of preparedness in the system which needs to be addressed to prevent recurrence.

Sexual Dimorphism in Colon Cancer

A higher incidence of colorectal cancer (CRC) is found in males compared to females. Young women (18-44 years) with CRC have a better survival outcome compared to men of the same age or compared to older women (over 50 years), indicating a global incidence of sexual dimorphism in CRC rates and survival. This suggests a protective role for the sex steroid hormone estrogen in CRC development. Key proliferative pathways in CRC tumorigenesis exhibit sexual dimorphism, which confer better survival in females through estrogen regulated genes and cell signaling. Estrogen regulates the activity of a class of Kv channels (KCNQ1:KCNE3), which control fundamental ion transport functions of the colon and epithelial mesenchymal transition through bi-directional interactions with the Wnt/β-catenin signalling pathway. Estrogen also modulates CRC proliferative responses in hypoxia via the novel membrane estrogen receptor GPER and HIF1A and VEGF signaling. Here we critically review recent clinical and molecular insights into sexual dimorphism of CRC biology modulated by the tumor microenvironment, estrogen, Wnt/β-catenin signalling, ion channels, and X-linked genes.

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.

Cost Implications of Reactive Versus Prospective Testing for Dihydropyrimidine Dehydrogenase Deficiency in Patients With Colorectal Cancer: A Single-Institution Experience

Background:

Severe toxicity is experienced by a substantial minority of patients receiving fluoropyrimidine-based chemotherapy, with approximately 20% of these severe toxicities attributable to polymorphisms in the DPYD gene. The DPYD codes for the enzyme dihydropyrimidine dehydrogenase (DPD) important in the metabolism of fluoropyrimidine-based chemotherapy. We questioned whether prospective DPYD mutation analysis in all patients commencing such therapy would prove more cost-effective than reactive testing of patients experiencing severe toxicity.

Methods:

All patients experiencing severe toxicity from fluoropyrimidine-based chemotherapy for colorectal cancer in an Irish private hospital over a 3-year period were tested for 4 DPYD polymorphisms previously associated with toxicity. The costs associated with an index admission for toxicity in DPD-deficient patients were examined. A cost analysis was undertaken comparing the anticipated cost of implementing screening for DPYD mutations versus current usual care. One-way sensitivity analysis was conducted on known input variables. An alternative scenario analysis from the perspective of the Irish health-care payer (responsible for public hospitals) was also performed.

Results:

Of 134 patients commencing first-line fluoropyrimidine chemotherapy over 3 years, 30 (23%) patients developed grade 3/4 toxicity. Of these, 17% revealed heterozygote DPYD mutations. The cost of hospitalization for the DPYD-mutated patients was €232 061, while prospectively testing all 134 patients would have cost €23 718. Prospective testing would result in cost savings across all scenarios.

Conclusions:

The cost of hospital admission for severe chemotherapy-related toxicity is significantly higher than the cost of prospective DPYD testing of each patient commencing fluoropyrimidine chemotherapy.

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.

GPER mediates differential effects of estrogen on colon cancer cell proliferation and migration under normoxic and hypoxic conditions

The estrogen receptor ERβ is the predominant ER subtype expressed in normal well-differentiated colonic epithelium. However, ERβ expression is lost under the hypoxic microenvironment as colorectal cancer (CRC) malignancy progresses. This raises questions about the role of signalling through other estrogen receptors such as ERα or G-protein coupled estrogen receptor (GPER, GPR30) by the estrogen 17β-estradiol (E2) under hypoxic conditions after ERβ is lost in CRC progression. We tested the hypothesis that E2 or hypoxia can act via GPER to contribute to the altered phenotype of CRC cells.

GPER expression was found to be up-regulated by hypoxia and E2 in a panel of CRC cell lines. The E2-modulated gene, Ataxia telangiectasia mutated (ATM), was repressed in hypoxia via GPER signalling. E2 treatment enhanced hypoxia-induced expression of HIF1-α and VEGFA, but repressed HIF1-α and VEGFA expression under normoxic conditions. The expression and repression of VEGFA by E2 were mediated by a GPER-dependent mechanism. E2 treatment potentiated hypoxia-induced CRC cell migration and proliferation, whereas in normoxia, cell migration and proliferation were suppressed by E2 treatment. The effects of E2 on these cellular responses in normoxia and hypoxia were mediated by GPER. In a cohort of 566 CRC patient tumor samples, GPER expression significantly associated with poor survival in CRC Stages 3-4 females but not in the stage-matched male population.

Our findings support a potentially pro-tumorigenic role for E2 in ERβ-negative CRC under hypoxic conditions transduced via GPER and suggest a novel route of therapeutic intervention through GPER antagonism.

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.

The development of cisplatin resistance in neuroblastoma is accompanied by epithelial to mesenchymal transition in vitro

Neuroblastoma is a challenging childhood malignancy, with a very high percentage of patients relapsing following acquisition of drug resistance, thereby necessitating the identification of mechanisms of drug resistance as well as new biological targets contributing to the aggressive pathogenicity of the disease. In order to investigate the molecular pathways that are involved with drug resistance in neuroblastoma, we have developed and characterised cisplatin resistant sublines SK-N-ASCis24, KellyCis83 and CHP-212Cis100, integrating data of cell behaviour, cytotoxicity, genomic alterations and modulation of protein expression. All three cisplatin resistant cell lines demonstrated cross resistance to temozolomide, etoposide and irinotecan, all of which are drugs in re-initiation therapy. Array CGH analysis indicated that resistant lines have acquired additional genomic imbalances. Differentially expressed proteins were identified by mass spectrometry and classified by bioinformatics tools according to their molecular and cellular functions and their involvement into biological pathways. Significant changes in the expression of proteins involved with pathways such as actin cytoskeletal signalling (p = 9.28E-10), integrin linked kinase (ILK) signalling (p = 4.01E-8), epithelial adherens junctions signalling (p = 5.49E-8) and remodelling of epithelial adherens junctions (p = 5.87E-8) pointed towards a mesenchymal phenotype developed by cisplatin resistant SK-N-ASCis24. Western blotting and confocal microscopy of MYH9, ACTN4 and ROCK1 coupled with invasion assays provide evidence that elevated levels of MYH9 and ACTN4 and reduced levels of ROCK1 contribute to the increased ROCK1-independent migratory potential of SK-N-ASCis24. Therefore, our results suggest that epithelial-to-mesenchymal transition is a feature during the development of drug resistance in neuroblastoma.

Modulation of chemotherapeutic drug resistance in neuroblastoma SK-N-AS cells by the neural apoptosis inhibitory protein and miR-520f

The acquisition of multidrug resistance is a major impediment to the successful treatment of neuroblastoma, a clinically heterogeneous cancer accounting for ∼15% of all pediatric cancer deaths. The MYCN transcription factor, whose gene is amplified in ∼30% of high-risk neuroblastoma cases, influences drug resistance by regulating a cadre of genes, including those involved with drug efflux, however, other high-risk subtypes of neuroblastoma lacking MYCN amplification, such as those with chromosome 11q deletions, also acquire multidrug resistance. To elucidate additional mechanisms involved with drug resistance in non-MYCN amplified tumour cells, an SK-N-AS subline (SK-N-AsCis24) that is significantly resistant to cisplatin and cross resistant to etoposide was developed through a pulse-selection process. High resolution aCGH analysis of SK-N-AsCis24 revealed a focal gain on chromosome 5 containing the coding sequence for the neural apoptosis inhibitory protein (NAIP). Significant overexpression of NAIP mRNA and protein was documented, while experimental modulation of NAIP levels in both SK-N-AsCis24 and in parental SK-N-AS cells confirmed that NAIP was responsible for the drug resistant phenotype by apoptosis inhibition. Furthermore, a decrease in the NAIP targeting microRNA, miR-520f, was also demonstrated to be partially responsible for increased NAIP levels in SK-N-AsCis24. Interestingly, miR-520f levels were determined to be significantly lower in postchemotherapy treatment tumours relative to matched prechemotherapy samples, consistent with a role for this miRNA in the acquisition of drug resistance in vivo, potentially through decreased NAIP targeting. Our findings provide biological novel insight into neuroblastoma drug-resistance and have implications for future therapeutic research.

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.

Estrogen reduces lipid content in the liver exclusively from membrane receptor signaling

Estrogen induces signal transduction through estrogen receptor α (ERα), which localizes to both the plasma membrane and nucleus. Using wild-type mice, ERα knockout (ERKO) mice, or transgenic mice expressing only the ligand-binding domain of ERα exclusively at the plasma membrane (MOER), we compared the transcriptional profiles of liver tissue extracts after mice were injected with the ERα agonist propyl-pyrazole-triol (PPT). The expression of many lipid synthesis-related genes was comparably decreased in livers from MOER or wild-type mice but was not suppressed in ERKO mice, indicating that only membrane-localized ERα was necessary for their suppression. Cholesterol, triglyceride, and fatty acid content was decreased only in livers from wild-type and MOER mice exposed to PPT, but not in the livers from the ERKO mice, validating the membrane-driven signaling pathway on a physiological level. PPT-triggered activation of ERα at the membrane induced adenosine monophosphate-activated protein kinase to phosphorylate sterol regulatory element-binding factor 1 (Srebf1), preventing its association with and therefore its proteolytic cleavage by site-1 protease. Consequently, Srebf1 was sequestered in the cytoplasm, preventing the expression of cholesterol synthesis-associated genes. Thus, we showed that inhibition of gene expression mediated by membrane-localized ERα caused a metabolic phenotype that did not require nuclear ERα.

MicroRNA-497 increases apoptosis in MYCN amplified neuroblastoma cells by targeting the key cell cycle regulator WEE1

Background

Neuroblastoma is responsible for 15% of all childhood cancer deaths. Despite advances in treatment and disease management, the overall 5-year survival rates remain poor in high-risk disease (25-40%). MiR-497 was previously identified by our laboratory as a member of a miRNA expression signature, predictive of neuroblastoma patient survival and has been reported as a tumor suppressor in a variety of other cancers. WEE1, a tyrosine kinase regulator of the cell cycle and predicted target of miR-497, has emerged as an oncogene in several cancer types and therefore represents an attractive potential target for novel therapy approaches in high-risk neuroblastoma. Our aim was to investigate the potential tumor suppressive role of miR-497 in high-risk neuroblastoma.

Methods

Expression levels of miR-497 and WEE1 in tissues and cells were determined using RT-PCR. The effect of miR-497 and siWEE1 on cell viability was evaluated using MTS assays, apoptosis levels were determined using FACS analysis of Annexin V/PI stained cells, and target protein expression was determined using western blot. Luciferase reporter plasmids were constructed to confirm direct targeting. Results were reported as mean±S.E.M and differences were tested for significance using 2-tailed Students t-test.

Results

We determined that miR-497 expression was significantly lower in high-risk MYCN amplified (MNA) tumors and that low miR-497 expression was associated with worse EFS and OS in our cohort. Over-expression of miR-497 reduced cell viability and increased apoptosis in MNA cells. We identified WEE1 as a novel target for miR-497 in neuroblastoma. Furthermore, our analysis showed that high WEE1 levels are significantly associated with poor EFS and OS in neuroblastoma and that siRNA knockdown of WEE1 in MNA cell lines results in significant levels of apoptosis, supporting an oncogenic role of WEE1 in neuroblastoma. Cisplatin (CDDP) treatment of both miR-497 over-expressing cells and WEE1 inhibited cells, resulted in a significant increase in apoptosis in MNA cells, describing a synergistic effect and therefore a potential therapeutic for high-risk neuroblastoma.

Conclusion

Our study’s results are consistent with miR-497 being a candidate tumor suppressor in neuroblastoma, through the direct targeting of WEE1. These findings re-enforce the proposal of WEE1 as a therapeutic target in neuroblastoma.

Inhibition of neuroblastoma tumor growth by targeted delivery of microRNA-34a using anti-disialoganglioside GD2 coated nanoparticles

Background

Neuroblastoma is one of the most challenging malignancies of childhood, being associated with the highest death rate in paediatric oncology, underlining the need for novel therapeutic approaches. Typically, patients with high risk disease undergo an initial remission in response to treatment, followed by disease recurrence that has become refractory to further treatment. Here, we demonstrate the first silica nanoparticle-based targeted delivery of a tumor suppressive, pro-apoptotic microRNA, miR-34a, to neuroblastoma tumors in a murine orthotopic xenograft model. These tumors express high levels of the cell surface antigen disialoganglioside GD2 (GD₂), providing a target for tumor-specific delivery.

Principal Findings

Nanoparticles encapsulating miR-34a and conjugated to a GD₂ antibody facilitated tumor-specific delivery following systemic administration into tumor bearing mice, resulted in significantly decreased tumor growth, increased apoptosis and a reduction in vascularisation. We further demonstrate a novel, multi-step molecular mechanism by which miR-34a leads to increased levels of the tissue inhibitor metallopeptidase 2 precursor (TIMP2) protein, accounting for the highly reduced vascularisation noted in miR-34a-treated tumors.

Significance

These novel findings highlight the potential of anti-GD₂-nanoparticle-mediated targeted delivery of miR-34a for both the treatment of GD₂-expressing tumors, and as a basic discovery tool for elucidating biological effects of novel miRNAs on tumor growth.

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

e11595

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.

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)