An Analysis of Ketamine Doses Administrated to Nonintubated Casualties Prehospital.

INTRODUCTION: Previous studies demonstrate that a significant proportion of casualties do not receive pain medication prehospital after traumatic injuries. To address possible reasons, the U.S. Military has sought to develop novel delivery methods to aid in administration of pain medications prehospital. We sought to describe the dose and route of ketamine administered prehospital to help inform materiel solutions. MATERIALS AND METHODS: This is a secondary analysis of a previously described dataset focused on prehospital data within the Department of Defense Trauma Registry from 2007 to 2020. We isolated encounters in which ketamine was administered along with the amount dosed and the route of administration in nonintubated patients. RESULTS: Within our dataset, 862 casualties met inclusion for this analysis. The median age was 28 and nearly all (98%) were male. Most were battle injuries (88%) caused by explosives (54%). The median injury severity score was 10 with the extremities accounting to the most frequent seriously injured body region (38%). The mean dose via intravenous route was 50.4 mg (n = 743, 95% CI 46.5-54.3), intramuscular was 66.7 mg (n = 234, 95% CI 60.3-73.1), intranasal was 56.5 mg (n = 10, 39.1-73.8), and intraosseous was 83.3 mg (n = 34, 66.3-100.4). Most had a medic or CLS in their chain of care (87%) with air evacuation as the primary mechanism of evacuation (86%). CONCLUSIONS: The average doses administered were generally larger than the doses recommended by Tactical Combat Casualty Care guidelines. Currently, guidelines may underdose analgesia. Our data will help inform materiel solutions based on end-user requirements.

Implementing Pool-Based Surveillance Testing for SARS-CoV-2 at the Army Public Health Center Laboratory and across the Army Public Health Laboratory Enterprise.

With limited clinical resources, burgeoning testing requests from Army and other Service units to clinical laboratories, and the continued spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) throughout the military population, the Army Public Health Laboratory (APHL) Enterprise was tasked to establish surveillance testing capabilities for active duty military populations in an expedient manner. Following a proof-of-concept study conducted by Public Health Command-Pacific, Public Health Command-Europe was the first public health laboratory to offer the capability to assess for SARS-CoV-2 in pooled samples, followed closely by the Army Public Health Center (APHC) at Aberdeen Proving Grounds, MD, paralleling the spread of the SARS-CoV-2 virus from China to Europe to the continental US. The APHLs have selected pool sizes of up to 10 samples per pool based on the best evidence available at the time of method development and validation. Real-Time quantitative Reverse Transcriptase-Polymerase Chain Reaction (qRT-PCR) assays using RNA extracts from pooled nasopharyngeal swabs preserved in viral transport media were selected to assess the presence of SARS-CoV-2. The rapid development of initial surveillance testing capabilities depended on existing equipment in each laboratory, with a plan to implement full operational capability using additional staff and common high-throughput platforms. APHL Enterprise has successfully used existing resources to begin to address the changing and complex needs for COVID-19 testing within the Army population. Successful implementation of pooled surveillance testing at the APHC Laboratory has enabled more than 8,600 Soldiers to avoid clinical testing to date. The APHC Laboratory alone has tested over 10,000 samples and prevented approximately 8,600 soldiers from seeking testing with clinical diagnostic assays.

Expanding Health Care Access Through Education: Dissemination and Implementation of the ECHO Model.

Project ECHO (Extension for Community Healthcare Outcomes) is an evidence-based model that provides high-quality medical education for common and complex diseases through telementoring and comanagement of patients with primary care clinicians. In a one to many knowledge network, the ECHO model helps to bridge the gap between primary care clinicians and specialists by enhancing the knowledge, skills, confidence, and practice of primary care clinicians in their local communities. As a result, patients in rural and urban underserved areas are able to receive best practice care without long waits or having to travel long distances. The ECHO model has been replicated in 43 university hubs in the United States and five other countries. A new replication tool was developed by the Project ECHO Pain team and U.S. Army Medical Command to ensure a high-fidelity replication of the model. The adoption of the tool led to successful replication of ECHO in the Army Pain initiative. This replication tool has the potential to improve the fidelity of ECHO replication efforts around the world.

The intraoperative administration of ketamine to burned U.S. service members does not increase the incidence of post-traumatic stress disorder.

AIM: Patients with severe burns typically undergo multiple surgeries, and ketamine is often used as part of the multimodal anesthetic regimen during such surgeries. The anesthetic ketamine is an N-methyl-D-aspartate receptor antagonist that also provides analgesia at subanesthetic doses, but the psychoactive side effects of ketamine have caused concern about its potential psychological effects on a combat-wounded population. Post-traumatic stress disorder (PTSD) affects approximately 30% of burned U.S. service members injured in Operation Iraqi Freedom/Operation Enduring Freedom. A preliminary analysis by our research group reported that patients who received perioperative ketamine had a significantly lower prevalence of PTSD than those injured service members who did not receive ketamine. We have now expanded this research to examine the relationship between ketamine and PTSD development in a much larger population. METHODS: A retrospective analysis on data from service members being treated for burns at the San Antonio Military Medical Center was conducted. Collected data included drugs received, injury severity score (ISS), total body surface area (TBSA) burned, length of hospital stay (LOS), number of intensive care unit days, number of surgeries, and PTSD Checklist-Military (PCL-M) scores and administration dates. Subjects were grouped based on intraoperative receipt of ketamine, and the groups were compared. The groups were binary for ketamine (yes or no), and dose of ketamine administered was not included in data analyses. Propensity score matching based on ISS and TBSA was performed to control for individual differences in burn severity. RESULTS: Two hundred eighty-nine burned U.S. service members received the PCL-M at least 30 days after injury. Of these subjects, 189 received intraoperative ketamine, and 100 did not. Despite significantly greater injuries, as evidenced by significantly higher TBSA burned and ISS (p < 0.01), patients who received ketamine did not screen positive for PTSD at a different rate than those patients who did not (24% vs. 26.98%, p = 0.582). Patients receiving intraoperative ketamine also underwent a significantly greater number of surgeries, spent more time in the hospital, spent more days in the ICU, and received more morphine equivalent units (p < 0.0001). Propensity score matching based on ISS and TBSA resulted in a total subject number of 130. In the matched samples, subjects who received ketamine still underwent significantly more surgeries and experienced longer hospital stays (p < 0.0001). Again, there was no statistically significant difference in the incidence of a positive screen for PTSD based upon the receipt of ketamine (28% vs. 26.15%, p = 0.843). CONCLUSIONS: Ketamine is often used in burn patients to reduce opioid usage and decrease the hemodynamic and respiratory side effects. Although this study does not show a benefit of ketamine on PTSD development that was identified in previous work with a smaller sample number, it does support the conclusion that ketamine does not increase PTSD development in burned service members.

State of the science review: Advances in pain management in wounded service members over a decade at war.

The pain conditions and comorbidities experienced by injured service members and the challenge of pain management by the military medical system offer a unique opportunity to inform pain management and medical research. In this article, acute and chronic pain issues, current treatment options and limitations, as well as novel approaches to pain management are discussed within the context of combat casualty care, from the battlefield to hospitalization and rehabilitation. This review will also highlight the current pain management limitations that need to be addressed in future clinical and basic science research to improve care for our nation's injured service members.

Curcumin: a novel therapeutic for burn pain and wound healing.

INTRODUCTION: Managing burn injury-associated pain and wounds is a major unresolved clinical problem. Opioids, nonsteroidal antiinflammatory drugs (NSAIDs), antidepressants and anticonvulsants remain the most common forms of analgesic therapy to treat burn patients. However, prolonged treatment with these drugs leads to dose escalation and serious side effects. Additionally, severe burn wounds cause scarring and are susceptible to infection. Recent encouraging findings demonstrate that curcumin, a major bioactive component found in turmeric, is a natural pharmacotherapeutic for controlling both severe burn pain and for improved wound healing. AREAS COVERED: This article covers current pr-clinical and clinical studies on the analgesic and wound healing effects. Particular emphasis has been placed on studies aimed at developing improved curcumin delivery vehicles that increase its bioavailability. Based on the available evidence, a hypothesis is proposed that the dual beneficial effects of curcumin, analgesia and enhanced wound healing are mediated through common anti-inflammatory mechanisms. EXPERT OPINION: Emerging studies have demonstrated that curcumin is a promising investigational drug to treat both pain and wounds. The adequate control of severe burn pain, particularly over the long courses required for healing, as well improvements in burn wound healing are unmet clinical needs.

Safety and efficacy of oral transmucosal fentanyl citrate for prehospital pain control on the battlefield.

BACKGROUND: Acute pain, resulting from trauma and other causes, is a common condition that imposes a need for prehospital analgesia on and off the battlefield. The narcotic most frequently used for prehospital analgesia on the battlefield during the past century has been morphine. Intramuscular morphine has a delayed onset of pain relief that is suboptimal and difficult to titrate. Although intravenously administered morphine can readily provide rapid and effective prehospital analgesia, oral transmucosal fentanyl citrate (OTFC) is a safe alternative that does not require intravenous access. This study evaluates the safety and efficacy of OTFC in the prehospital battlefield environment. METHODS: Data collected during combat deployments (Afghanistan and Iraq) from March 15, 2003, to March 31, 2010, were analyzed. Patients were US Army Special Operations Command casualties. Patients receiving OTFC for acute pain were evaluated. Pretreatment and posttreatment pain intensities were quantified by the verbal numeric rating scale (NRS) from 0 to 10. OTFC adverse effects and injuries treated were also evaluated. RESULTS: A total of 286 patients were administered OTFC, of whom 197 had NRS pain evaluations conducted before and approximately 15 minutes to 30 minutes following treatment. The difference between NRS pain scores at 0 minutes (NRS, 8.0 [1.4]) and 15 minutes to 30 minutes (NRS, 3.2 [2.1]) was significant (p < 0.001). Only 18.3% (36 of 197) of patients were also administered other types of analgesics. Nausea was the most common adverse effect as reported by 12.7% (25 of 197) of patients. The only major adverse effect occurred in the patient who received the largest opioid dose, 3,200-µg OTFC and 20-mg morphine. This patient exhibited hypoventilation and saturation of less than 90% requiring low-dose naloxone. CONCLUSION: OTFC is a rapid and noninvasive pain management strategy that provides safe and effective analgesia in the prehospital battlefield setting. OTFC has considerable implications for use in civilian prehospital and austere environments. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Translational advances in pain and anesthesia for cancer patients.

Effective cancer pain management requires multidisciplinary approaches for multimodal analgesia. Although opioids have been the cornerstone, developments such as regional anesthesia and interventional pain techniques, complementary and alternative medicine, and new pharmaceuticals also have shown promise to relieve cancer pain. This overview of relevant clinical efforts and the modern day state of the science will afford a better understanding of pain mechanisms and multimodal approaches beneficial in optimizing analgesia for cancer patients.

The relationship between gabapentin and pregabalin and posttraumatic stress disorder in burned servicemembers.

Posttraumatic stress disorder (PTSD) affects approximately 30% of burned Servicemembers returning from Operation Iraqi Freedom/Operation Enduring Freedom. Gabapentin and pregabalin are anticonvulsant drugs that limited evidence suggests may also be effective treatments for some psychological disorders. This study examines the relationship between these anticonvulsants and PTSD development in burned Servicemembers. Drugs received, injury severity score, TBSA burned, length of hospital stay, number of intensive care unit days, number of surgeries, and PTSD Checklist-Military scores and administration dates were collected. Subjects were grouped based on receipt of gabapentin or pregabalin, and the groups were compared. The primary outcome was incidence of a positive screen for PTSD. Because injury severity was significantly different between the two groups, propensity score matching based on injury severity score and TBSA was performed. Two hundred ninety burned Servicemembers received the PTSD Checklist-Military at least 30 days after injury. Of these subjects, 104 received gabapentin, pregabalin, or both and 186 did not. Despite significantly greater injuries, the group that received gabapentin or pregabalin did not develop PTSD at a different rate than those patients who did (P = .727). Propensity score matching resulted in 57 patients in each group; there was no difference between these groups in the incidence of PTSD (P = .663). These data suggest that gabapentin or pregabalin administration may not affect PTSD development in burned Servicemembers. Many factors influence the development and progression of PTSD, but few drugs have been identified that are effective at treating or preventing PTSD.

Use of ultra rapid opioid detoxification in the treatment of US military burn casualties.

BACKGROUND: The purpose of this case series was to review the management of burn patients who requested ultrarapid opioid detoxification under anesthesia after extended duration of narcotic use for chronic pain related to burn injury. METHODS: The treatment plan of six opioid-dependent burn patients was analyzed to assess the effectiveness of our detoxification practice to date. Demographic and clinical information was used to characterize the patient population served: age, burn size, injury severity, duration of narcotic use before detoxification intervention, and length of hospitalization stay. Daily narcotic consumption, in morphine equivalent units, was noted both before and after detoxification. RESULTS: Six burn patients (average age, 31 years) underwent detoxification at the Burn Center during a hospitalization lasting between 1 day and 2 days. Average burn size was 38% total body surface area (range, 17-65); average Injury Severity Score was 30 (range, 25-38). Mean duration of narcotic use was 672 days (range, 239-1,156 days); average use of narcotics at time of detoxification was >200 units daily. Mean outpatient consumption for opioids after the intervention was minimal (<25 units/d). No complications were noted during any procedures. CONCLUSIONS: The results of ultrarapid opioid detoxification under anesthesia suggests that it is safe and effective for treating opioid addiction in military burn casualties when a coordinated, multidisciplinary approach is used. Safety and effectiveness to date validate current practice and supports incorporation into clinical practice guidelines. Further clinical research is warranted to identify those patients who may benefit most from detoxification and to determine the timing of such treatment.

Virtual reality pain control during burn wound debridement of combat-related burn injuries using robot-like arm mounted VR goggles.

BACKGROUND: This is the first controlled study to explore whether adjunctive immersive virtual reality (VR) can reduce excessive pain of soldiers with combat-related burn injuries during wound debridement. METHODS: Patients were US soldiers burned in combat attacks involving explosive devices in Iraq or Afghanistan. During the same wound care session using a within-subject experimental design, 12 patients received half of their severe burn wound cleaning procedure (~6 minutes) with standard of care pharmacologies and half while in VR (treatment order randomized). Three 0 to 10 Graphic Rating Scale pain scores for each of the treatment conditions served as the primary variables. RESULTS: Patients reported significantly less pain when distracted with VR. "Worst pain" (pain intensity) dropped from 6.25 of 10 to 4.50 of 10. "Pain unpleasantness" ratings dropped from "moderate" (6.25 of 10) to "mild" (2.83 of 10). "Time spent thinking about pain" dropped from 76% during no VR to 22% during VR. Patients rated "no VR" as "no fun at all" (<1 of 10) and rated VR as "pretty fun" (7.5 of 10). Follow-up analyses showed VR was especially effective for the six patients who scored 7 of 10 or higher (severe to excruciating) on the "worst pain" (pain intensity) ratings. CONCLUSIONS: These preliminary results provide the first evidence from a controlled study that adjunctive immersive VR reduced pain of patients with combat-related burn injuries during severe burn wound debridement. Pain reduction during VR was greatest in patients with the highest pain during no VR. These patients were the first to use a unique custom robot-like arm mounted VR goggle system.

Relationships between early acute pain scores, autonomic nervous system function, and injury severity in wounded soldiers.

BACKGROUND: Acute pain after injury affects the comfort and function of the wounded soldier and the physiology of multiple body systems. In the civilian population, pain alters the function of the autonomic nervous system, causing increased heart rate and blood pressure. However, there are no data regarding the impact of combat-related pain on physiologic responses. This study is a retrospective analysis that examined the relationship of pain and physiologic parameters in injured soldiers. METHODS: After Institutional Review Board approval, the Joint Trauma Theater Registry (JTTR) was queried to identify soldiers who had pain scores recorded in the Emergency Department (ED) in theater. Subject data collected from the JTTR included the following: pain score, Injury Severity Score (ISS), blood pressure, heart rate, and respiratory rate. RESULTS: We identified 2,646 soldiers with pain scores recorded in the ED. The pain score was not related to most physiologic parameters measured in the ED. Pain intensity had no correlation with blood pressure or heart rate. However, there were relationships between the pain score and respiratory rate, with patients reporting a pain score of 10 having a slightly higher respiratory rate. Increasing pain scores were also associated with increased ISS (p < 0.001). CONCLUSIONS: In contrast to data from civilian patients, early pain scores were not related to heart rate or blood pressure. A pain score of 10 corresponded to an increased respiratory rate. Despite little relationship between pain and injury severity in the civilian population, the increasing ISS was proportional to the pain scale in wounded soldiers.

The relationship of early pain scores and posttraumatic stress disorder in burned soldiers.

Early acute pain after injury has been linked to long-term patient outcomes, including the development of posttraumatic stress disorder (PTSD). Several studies have identified a negative correlation between early anesthetic/analgesic usage and subsequent development of PTSD. This retrospective study examined the relationship between early acute pain and severity of PTSD symptoms in soldiers with burn injuries. Of the soldiers injured in Overseas Contingency Operations who had pain scores recorded at admission to the Emergency Department, 113 had burn injuries. Of those transferred to the military burn center, 47 were screened for PTSD using the PTSD checklist-military (PCL-M) survey at least 1 month after injury. Soldiers with mild, moderate, and severe pain scores had similar Injury Severity Scores and TBSA burned (P = .339 and .570, respectively). However, there were significant differences in PCL-M scores between the mild and severe pain groups (P = .017). The pain levels positively correlated with the PCL-M score (rho = 0.41, P = .004) but not with injury severity markers (Injury Severity Score and TBSA). These data suggest that early acute pain may be related to increased PCL-M score and PTSD symptoms. The intensity of pain was not related to the injury severity, and these data also show no association between pain intensity and physiological measures, including blood pressure and heart rate. However, this is a small sample size, and many other factors likely influence PTSD development. Further study is necessary to explore the relationship between early acute pain and subsequent development of PTSD symptoms.

Solution structure of Gfi-1 zinc domain bound to consensus DNA.

Gfi-1 is a crucial transcriptional repressor for the precise regulation of cell proliferation and differentiation in hematopoiesis. Recently, this protein has also been demonstrated to be capable of restricting the proliferation of hematopoietic stem cells, a process that appears to be vital for the long-term competency of hematopoietic stem cells. These two seemingly opposite outcomes of regulation are likely to arise from its interactions with a variety of cellular partners. Such interactions can directly affect the genes that Gfi-1 recognizes through its DNA binding zinc-finger domain. In this work, we report the determination of the solution structure of Gfi-1 zinc fingers 3-5 in complex with a 16-mer consensus DNA using multidimensional NMR method. Unlike a proposed minor-groove binding model based on methylation interference experiments, our structure clearly shows that Gfi-1 zinc fingers 3-5 bind into the major groove of the target DNA reminiscent of canonical C(2)H(2) zinc-finger domains. The fourth and fifth zinc fingers recognize the AATC core sequence by forming base-specific hydrogen bonds between the side chains of Asn382, Gln379, and Asp354 and the bases of the invariant adenines and cytosine. Overall, the current work provides valuable insight into the structural determinants for DNA binding specificity, in particular for the TCA triplet that has not been observed in any other structures of zinc finger-DNA complexes, as well as molecular rationales for a naturally occurring mutation that causes acute myeloid leukemia.

The relationship of intravenous midazolam and posttraumatic stress disorder development in burned soldiers.

BACKGROUND: Midazolam, a short-acting benzodiazepine, is administered preoperatively and intraoperatively for amnesia and anxiolysis. Subsequently, patients often do not recall events which occurred while they were sedated. Recent studies have also reported retrograde facilitation after midazolam exposure. Posttraumatic stress disorder PTSD is based on memory of a traumatic event. Because of the concern that midazolam may enhance memory of the traumatic event in which soldiers were injured, we investigated the prevalence of PTSD in those burned soldiers who received perioperative midazolam and those who did not. We also investigated the intensity of the memories related to the traumatic event. METHODS: After institutional review board approval, all charts of US soldiers who completed the PTSD Checklist-Military (PCL-M) screening tool (2004-2008) after admission to US Army Institute of Surgical Research were reviewed to determine the number of operations, the anesthetic regime, total body surface area (TBSA) burned, and Injury Severity Score (ISS). RESULTS: The PCL-M was completed by 370 burned soldiers from Operation Iraqi Freedom/Operation Enduring Freedom. During surgery, 142 received midazolam, whereas 69 did not. The prevalence of PTSD was higher in soldiers receiving midazolam as compared with those who did not (29% vs. 25%) (p = 0.481). Both groups had similar injuries based on TBSA and ISS. Patients who received midazolam also had similar scores on PCL-M questions related to memory of the event. CONCLUSIONS: Rates of PTSD are not statistically different in combat casualties receiving midazolam during intraoperative procedures. Intraoperative midazolam is not associated with increased PTSD development or with increased intensity of memory of the traumatic event. Patients receiving midazolam had similar injuries (TBSA and ISS) and underwent a similar number of operations as those not receiving midazolam.

The effect of propranolol on posttraumatic stress disorder in burned service members.

Posttraumatic stress disorder (PTSD) is reported to affect almost one third of the civilian burn patient population. Predisposing factors for PTSD include experiencing a traumatic event. Of Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) soldiers returning home after deployment without injury, 17% reported cognitive symptoms of PTSD. The authors recent study of soldiers burned in OIF/OEF showed a PTSD prevalence of approximately 30%, which is similar to civilian studies. Burns are characterized by hypermetabolism and increased catecholamine levels. beta-Adrenergic receptor blocking agents, like propranolol, decrease catecholamine levels. Propranolol may reduce consolidation of memory and a prophylaxis for PTSD. This retrospective study examines the relationship between PTSD prevalence and propranolol administration. After institutional review board approval, propranolol received, number of surgeries, anesthetic/analgesic regimen, TBSA burned, and injury severity score were collected from patients charts. The military burn center received 603 soldiers injured in OIF/OEF, of which 226 completed the PTSD Checklist-Military. Thirty-one soldiers received propranolol and 34 matched soldiers did not. In propranolol patients, the prevalence of PTSD was 32.3% vs 26.5% in those not receiving propranolol (P = .785). These data suggest propranolol does not decrease PTSD development in burned soldiers. The prevalence of PTSD in patients receiving propranolol is the same as those not receiving propranolol. More research is needed to determine the relationship between PTSD and propranolol.

The correlation between ketamine and posttraumatic stress disorder in burned service members.

BACKGROUND: Predisposing factors for posttraumatic stress disorder (PTSD) include experiencing a traumatic event, threat of injury or death, and untreated pain. Ketamine, an anesthetic, is used at low doses as part of a multimodal anesthetic regimen. However, since ketamine is associated with psychosomatic effects, there is a concern that ketamine may increase the risk of developing PTSD. This study investigated the prevalence of PTSD in Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) service members who were treated for burns in a military treatment center. METHODS: The PTSD Checklist-Military (PCL-M) is a 17-question screening tool for PTSD used by the military. A score of 44 or higher is a positive screen for PTSD. The charts of all OIF/OEF soldiers with burns who completed the PCL-M screening tool (2002-2007) were reviewed to determine the number of surgeries received, the anesthetic regime used, including amounts given, the total body surface area burned, and injury severity score. Morphine equivalent units were calculated using standard dosage conversion factors. RESULTS: The prevalence of PTSD in patients receiving ketamine during their operation(s) was compared with patients not receiving ketamine. Of the 25,000 soldiers injured in OIF/OEF, United States Army Institute of Surgical Research received 603 burned casualties, of which 241 completed the PCL-M. Of those, 147 soldiers underwent at least one operation. Among 119 patients who received ketamine during surgery and 28 who did not; the prevalence of PTSD was 27% (32 of 119) versus 46% (13 of 28), respectively (p = 0.044). CONCLUSIONS: Contrary to expectations, patients receiving perioperative ketamine had a lower prevalence of PTSD than soldiers receiving no ketamine during their surgeries despite having larger burns, higher injury severity score, undergoing more operations, and spending more time in the ICU.

RUNX1 (AML-1) and RUNX2 (AML-3) cooperate with prostate-derived Ets factor to activate transcription from the PSA upstream regulatory region.

The RUNX transcription factors (RUNX1, RUNX2, and RUNX3) play essential roles in hematopoiesis and skeletal development. Consistent with these roles in differentiation and cell cycle, the activity of both RUNX1 and RUNX3 is perturbed in cancer. To determine a role for the RUNX factors in prostate biology, we investigated the expression of RUNX factors in prostate epithelial cell lines and normal prostate tissue. RUNX1, RUNX2, and RUNX3 were expressed in both normal prostate tissue and an immortalized, non-transformed cell line. We found that prostate cancer-derived cell lines expressed RUNX1 and RUNX2, but not RUNX3. Next, we sought to identify prostate-specific genes whose expression could be regulated by RUNX proteins. Four consensus RUNX sites are located within the prostate-specific antigen (PSA) regulatory region. Chromatin immunoprecipitation (ChIP) analysis showed that RUNX1 is specifically bound to the PSA regulatory region in LNCaP cells. RUNX1 and RUNX2 activated the PSA regulatory region alone or cooperatively with prostate-derived ETS factor (PDEF) and RUNX1 physically associated with PDEF. Taken together, our results suggest that RUNX factors participate in prostate epithelial cell function and cooperate with an Ets transcription factor to regulate PSA gene expression.

Mtgr1 is a transcriptional corepressor that is required for maintenance of the secretory cell lineage in the small intestine.

Two members of the MTG/ETO family of transcriptional corepressors, MTG8 and MTG16, are disrupted by chromosomal translocations in up to 15% of acute myeloid leukemia cases. The third family member, MTGR1, was identified as a factor that associates with the t(8;21) fusion protein RUNX1-MTG8. We demonstrate that Mtgr1 associates with mSin3A, N-CoR, and histone deacetylase 3 and that when tethered to DNA, Mtgr1 represses transcription, suggesting that Mtgr1 also acts as a transcriptional corepressor. To define the biological function of Mtgr1, we created Mtgr1-null mice. These mice are proportionally smaller than their littermates during embryogenesis and throughout their life span but otherwise develop normally. However, these mice display a progressive reduction in the secretory epithelial cell lineage in the small intestine. This is not due to the loss of small intestinal progenitor cells expressing Gfi1, which is required for the formation of goblet and Paneth cells, implying that loss of Mtgr1 impairs the maturation of secretory cells in the small intestine.

Gfi-1 attaches to the nuclear matrix, associates with ETO (MTG8) and histone deacetylase proteins, and represses transcription using a TSA-sensitive mechanism.

Gfi-1 and Gfi-1B can repress transcription and play important roles in hematopoietic cell survival and differentiation. Although these proteins are known to bind DNA through a C-terminal zinc-finger domain and may require an N-terminal SNAG domain (SNAIL/Gfi-1) to repress transcription, the mechanism by which Gfi-1 and Gfi-1B act is unknown. A first step towards understanding the mechanism by which these proteins repress transcription is to identify interacting proteins that could contribute to transcriptional repression. ETO (also termed MTG8), was first identified through its involvement in the (8;21) translocation associated with acute myelogenous leukemia. It attaches to the nuclear matrix and associates with histone deacetylases and the co-repressors N-CoR, SMRT, and mSin3A, and may act as a co-repressor for site-specific transcriptions factors. In this report we demonstrate that Gfi-1 interacts with ETO and related proteins both in vitro and in vivo and with histone deacetylase proteins in vivo. We observed that a portion of Gfi-1 and Gfi-1B associated with the nuclear matrix, as is the case with ETO. Moreover, Gfi-1 and ETO co-localize to punctate subnuclear structures. When co-expressed in mammalian cells, Gfi-1 associates with histone deacetylse-1 (HDAC-1), HDAC-2, and HDAC-3. These data identify ETO as a partner for Gfi-1 and Gfi-1B, and suggest that Gfi-1 proteins repress transcription through recruitment of histone deacetylase-containing complexes.