Survival following liver transplantation for locally advanced, unresectable intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (iCCA) has previously been considered a contraindication to liver transplantation (LT). However, recent series showed favorable outcomes for LT after neoadjuvant therapy. Our center developed a protocol for neoadjuvant therapy and LT for patients with locally advanced, unresectable iCCA in 2010. Patients undergoing LT were required to demonstrate disease stability for 6 months on neoadjuvant therapy with no extrahepatic disease. During the study period, 32 patients were listed for LT and 18 patients underwent LT. For transplanted patients, the median number of iCCA tumors was 2, and the median cumulative tumor diameter was 10.4 cm. Patients receiving LT had an overall survival at 1-, 3-, and 5-years of 100%, 71%, and 57%. Recurrences occurred in seven patients and were treated with systemic therapy and resection. The study population had a higher than expected proportion of patients with genetic alterations in fibroblast growth factor receptor (FGFR) and DNA damage repair pathways. These data support LT as a treatment for highly selected patients with locally advanced, unresectable iCCA. Further studies to identify criteria for LT in iCCA and factors predicting survival are warranted.

64Cu/177Lu-DOTA-diZD, a Small-Molecule-Based Theranostic Pair for Triple-Negative Breast Cancer.

Despite advances in targeted therapies, the prognosis for patients with triple-negative breast cancer (TNBC) is poor because there are few actionable molecular targets. The dependence of solid tumor growth on angiogenesis prompted our development of angiogenic-receptor-targeted radionuclide therapy (TRT) to treat TNBC by targeted delivery of therapeutic doses of ionizing radiation to tumors. A high-affinity vascular endothelial growth factor receptor (VEGFR)-targeted agent, diZD, was synthesized and labeled with 177Lu and 64Cu by 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelator giving the TRT agent, 177Lu-DOTA-diZD, and PET imaging agent, 64Cu-DOTA-diZD. We showed that "64Cu/177Lu"-DOTA-diZD radiotracers are a promising theranostic pair for TNBC. 4T1-bearing mice treated with 177Lu-DOTA-diZD-based TRT survived with a median of 28 days, which was significantly longer than that of control mice as 18 days. Anti-PD1 immunotherapy resulted in a shorter median survival of 16 days. This work presents for the first time that small-molecule VEGFR-oriented TRT is a promising therapeutic option to treat "immunogenic cold" TNBC.

Structural Analysis of Hippocampal Kinase Signal Transduction.

Kinases are a major clinical target for human diseases. Identifying the proteins that interact with kinases in vivo will provide information on unreported substrates and will potentially lead to more specific methods for therapeutic kinase regulation. Here, endogenous immunoprecipitations of evolutionally distinct kinases (i.e., Akt, ERK2, and CAMK2) from rodent hippocampi were analyzed by mass spectrometry to generate three highly confident kinase protein-protein interaction networks. Proteins of similar function were identified in the networks, suggesting a universal model for kinase signaling complexes. Protein interactions were observed between kinases with reported symbiotic relationships. The kinase networks were significantly enriched in genes associated with specific neurodevelopmental disorders providing novel structural connections between these disease-associated genes. To demonstrate a functional relationship between the kinases and the network, pharmacological manipulation of Akt in hippocampal slices was shown to regulate the activity of potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel(HCN1), which was identified in the Akt network. Overall, the kinase protein-protein interaction networks provide molecular insight of the spatial complexity of in vivo kinase signal transduction which is required to achieve the therapeutic potential of kinase manipulation in the brain.

Gene repressive mechanisms in the mouse brain involved in memory formation.

Gene regulation in the brain is essential for long-term plasticity and memory formation. Despite this established notion, the quantitative translational map in the brain during memory formation has not been reported. To systematically probe the changes in protein synthesis during memory formation, our recent study exploited ribosome profiling using the mouse hippocampal tissues at multiple time points after a learning event. Analysis of the resulting database revealed novel types of gene regulation after learning. First, the translation of a group of genes was rapidly suppressed without change in mRNA levels. At later time points, the expression of another group of genes was downregulated through reduction in mRNA levels. This reduction was predicted to be downstream of inhibition of ESR1 (Estrogen Receptor 1) signaling. Overexpressing Nrsn1, one of the genes whose translation was suppressed, or activating ESR1 by injecting an agonist interfered with memory formation, suggesting the functional importance of these findings. Moreover, the translation of genes encoding the translational machineries was found to be suppressed, among other genes in the mouse hippocampus. Together, this unbiased approach has revealed previously unidentified characteristics of gene regulation in the brain and highlighted the importance of repressive controls. [BMB Reports 2016; 49(4): 199-200].

Multiple repressive mechanisms in the hippocampus during memory formation.

Memory stabilization after learning requires translational and transcriptional regulations in the brain, yet the temporal molecular changes that occur after learning have not been explored at the genomic scale. We used ribosome profiling and RNA sequencing to quantify the translational status and transcript levels in the mouse hippocampus after contextual fear conditioning. We revealed three types of repressive regulations: translational suppression of ribosomal protein-coding genes in the hippocampus, learning-induced early translational repression of specific genes, and late persistent suppression of a subset of genes via inhibition of estrogen receptor 1 (ESR1/ERα) signaling. In behavioral analyses, overexpressing Nrsn1, one of the newly identified genes undergoing rapid translational repression, or activating ESR1 in the hippocampus impaired memory formation. Collectively, this study unveils the yet-unappreciated importance of gene repression mechanisms for memory formation.

The microtubule nucleation activity of centrobin in both the centrosome and cytoplasm.

Centrobin resides in daughter centriole and play a critical role in centriole duplication. Nucleation and stabilization of microtubules are known biological activities of centrobin. Here, we report a specific localization of centrobin outside the centrosome. Centrobin was associated with the stable microtubules. In hippocampal cells, centrobin formed cytoplasmic dots in addition to the localization at both centrosomes with the mother and daughter centrioles. Such specific localization pattern suggests that cytoplasmic centrobin is not just a reserved pool for centrosomal localization but also has a specific role in the cytoplasm. In fact, centrobin enhanced microtubule formation outside as well as inside the centrosome. These results propose specific roles of the cytoplasmic centrobin for noncentrosomal microtubule formation in specific cell types and during the cell cycle.

Estimating dynamic lung images from high-dimension chest surface motion using 4D statistical model.

Computed Tomography (CT) has been widely used in image-guided procedures such as intervention and radiotherapy of lung cancer. However, due to poor reproducibility of breath holding or respiratory cycles, discrepancies between static images and patient's current lung shape and tumor location could potentially reduce the accuracy for image guidance. Current methods are either using multiple intra-procedural scans or monitoring respiratory motion with tracking sensors. Although intra-procedural scanning provides more accurate information, it increases the radiation dose and still only provides snapshots of patient's chest. Tracking-based breath monitoring techniques can effectively detect respiratory phases but have not yet provided accurate tumor shape and location due to low dimensional signals. Therefore, estimating the lung motion and generating dynamic CT images from real-time captured high-dimensional sensor signals acts as a key component for image-guided procedures. This paper applies a principal component analysis (PCA)-based statistical model to establish the relationship between lung motion and chest surface motion from training samples, on a template space, and then uses this model to estimate dynamic images for a new patient from the chest surface motion. Qualitative and quantitative results showed that the proposed high-dimensional estimation algorithm yielded more accurate 4D-CT compared to fiducial marker-based estimation.

Optimization of AAV expression cassettes to improve packaging capacity and transgene expression in neurons.

Adeno-associated virus (AAV) vectors can deliver transgenes to diverse cell types and are therefore useful for basic research and gene therapy. Although AAV has many advantages over other viral vectors, its relatively small packaging capacity limits its use for delivering large genes. The available transgene size is further limited by the existence of additional elements in the expression cassette without which the gene expression level becomes much lower. By using alternative combinations of shorter elements, we generated a series of AAV expression cassettes and systematically evaluated their expression efficiency in neurons to maximize the transgene size available within the AAV packaging capacity while not compromising the transgene expression. We found that the newly developed smaller expression cassette shows comparable expression efficiency with an efficient vector generally used for strong gene expression. This new expression cassette will allow us to package larger transgenes without compromising expression efficiency.

Efficient electroporation of liposomes doped with pore stabilizing nisin.

CONTEXT: Liposomes have a long history as passive and active drug carriers. Recently, a few methods have been realized to control the release from liposomes, including heating, ultrasound and laser. OBJECTIVE: We report on a new approach to drive release from liposomes using electric fields. MATERIALS AND METHODS: Liposomes were manufactured containing a high concentration of (quenched) 5-6 carboxyfluorescein dye. Nisin, a well-known amphiphilic peptide lantibiotic that works by stabilizing pores formed in cell membranes, was mixed in solution inside or outside the liposomes. The liposomes were then electroporated using a range of voltages, and assayed for increases in fluorescence due to release of dye. Release was measured against positive and negative controls, with positive control release driven by a strong detergent. RESULTS: Our results demonstrate that the addition of nisin significantly reduces the electric field required to release the contents of liposomes, from 2000 V/m to approximately 200 V/m. This result proves that, in principle, electroporation (EP) of liposomes doped with small amounts of amphiphilic pore stabilizing peptides may be a practical means to drive release of liposomal contents in vivo. CONCLUSION: Drug delivery from liposomes doped with amphiphilic peptides using EP is feasible. This technique could be developed into a potent adjuvant to tumor ablation using irreversible EP.

A fast CT and CT-fluoroscopy registration algorithm with respiratory motion compensation for image-guided lung intervention.

CT-fluoroscopy (CTF) is an efficient imaging technique for guiding percutaneous lung intervention such as biopsy and ablation. In CTF-guided procedures, four to ten axial images are captured in a very short time period during breath holding to provide near real-time feedback of patients' anatomy so that physicians can adjust the needle as it is advanced toward a target lesion. Although popularly used in clinics, this procedure requires frequent scans to guide the needle, which may cause increased procedure time, complication rates, and radiation exposure to both clinicians and patients. In addition, CTF only generates a limited number of 2-D axial images and does not provide sufficient 3-D anatomical information. Therefore, how to provide volumetric anatomical information using CTF while reducing intraoperative scan is an important and challenging problem. In this paper, we propose a fast CT-CTF deformable registration algorithm that warps the inhale preprocedural CT onto the intraprocedural CTF for guidance in 3-D. In the algorithm, the deformation in the transverse plane is modeled using 2-D B-Spline, and the deformation along z-direction is regularized by smoothness constraint. A respiratory motion compensation framework is also incorporated for accurate registration. A parallel implementation strategy is adopted to accomplish the registration in several seconds. With electromagnetic tracking, the needle position can be superimposed onto the deformed inhale CT image, thereby providing 3-D image guidance during breath holding. Experiments were conducted using both simulated CTF images with known deformation and real CTF images captured during lung cancer biopsy studies. The experiments demonstrated satisfactory registration results of our proposed fast CT-CTF registration algorithm.

Giant invasive spinal schwannoma: its clinical features and surgical management.

BACKGROUND: Giant invasive spinal schwannoma (GISS) is defined as a lesion that extends over > 2 vertebral levels, erodes vertebral bodies, and extends posteriorly and laterally into the myofascial planes. Because of its rarity, few reports have been issued. OBJECTIVE: To analyze the clinical features and outcomes of GISS and to discuss surgical strategies. METHODS: We analyzed the medical records, pathological findings, and radiographic studies of patients with GISS. RESULTS: Fourteen patients with GISS were surgically treated between 2002 and 2007. Five lesions were in the sacral region, 4 in the lumbosacral, 2 in the thoracolumbar, and 1 each in the cervical, cervicothoracic, and thoracic regions. Gross total resection was performed in 11 of the 14 patients. Satisfactory decompression was performed in all patients for neural compression. Postoperatively, all patients showed relief of preoperative pain and paresthesia. The growth potential with the Ki-67 index was > 2% in 6 patients, and 4 of them experienced tumor regrowth or recurrence. All patients were followed up for at least 24 months. Final follow-up magnetic resonance images showed asymptomatic small tumor recurrence on the sacrum in 2 patients. Two patients required spinal stabilization. No instability was found on follow-up. CONCLUSION: Total resection is the treatment of choice for patients with GISS and provides functional improvements, low permanent morbidity, and a low rate of recurrence. Total resection of the intraspinal portion and regular follow-up with consideration of the Ki-67 index is recommended when total resection is not achieved.

PI3Kγ is required for NMDA receptor-dependent long-term depression and behavioral flexibility.

Phosphatidylinositol 3-kinase (PI3K) has been implicated in synaptic plasticity and other neural functions in the brain. However, the role of individual PI3K isoforms in the brain is unclear. We investigated the role of PI3Kγ in hippocampal-dependent synaptic plasticity and cognitive functions. We found that PI3Kγ has a crucial and specific role in NMDA receptor (NMDAR)-mediated synaptic plasticity at mouse Schaffer collateral-commissural synapses. Both genetic deletion and pharmacological inhibition of PI3Kγ disrupted NMDAR long-term depression (LTD) while leaving other forms of synaptic plasticity intact. Accompanying this physiological deficit, the impairment of NMDAR LTD by PI3Kγ blockade was specifically correlated with deficits in behavioral flexibility. These findings suggest that a specific PI3K isoform, PI3Kγ, is critical for NMDAR LTD and some forms of cognitive function. Thus, individual isoforms of PI3Ks may have distinct roles in different types of synaptic plasticity and may therefore influence various kinds of behavior.

CT and MRI improve detection of hepatocellular carcinoma, compared with ultrasound alone, in patients with cirrhosis.

BACKGROUND & AIMS: In patients with cirrhosis, hepatocellular carcinoma (HCC) is detected by ultrasound (US), computed tomography (CT), or magnetic resonance imaging (MRI); US is recommended for screening and surveillance. We performed a retrospective analysis of the abilities of these cross-sectional imaging modalities to detect HCC. METHODS: We analyzed data from 638 consecutive adult patients with cirrhosis who received liver transplants within 6 months of imaging at a tertiary care institution. Imaging reports and serum alpha-fetoprotein levels were compared with results from pathology analysis of explants as the reference standard. Sensitivities of US, CT, and MRI were calculated overall and in defined size categories. False-positive imaging results and patient-based specificities were evaluated. RESULTS: Of the 638 patients, 225 (35%) had HCC, confirmed by pathology analysis of liver explants. In 23 cases, the lesions were infiltrative or extensively multifocal. In the remaining 202 explants (337 numerable, discrete nodules), respective lesion-based sensitivities of US, CT, and MRI were 46%, 65%, and 72% overall and 21%, 40%, and 47% for small (<2 cm) HCC. The sensitivity of US increased with the availability of CT or MRI data (P = .049); sensitivity values were 62% and 85% for lesions 2-4 and ≥ 4 cm, respectively. Patient-based specificities of US, CT, and MRI were 96%, 96%, and 87%, respectively. CONCLUSIONS: US, CT, and MRI did not detect small HCC lesions with high levels of sensitivity, although CT and MRI provide substantial improvements over unenhanced US in patients with cirrhosis who received liver transplants.

Sequential changes in echogenicity and conspicuity of small hepatocellular carcinoma on gray scale sonography after transcatheter arterial chemoembolization.

OBJECTIVE: The purpose of this study was to assess sequential changes in the echogenicity and conspicuity of small hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE). METHODS: Seventy patients with nodular HCC underwent 3 serial abdominal sonographic examinations before (t0), immediately after (t1), and 2 to 4 days after (t2) TACE. The echogenicity and conspicuity of the HCC nodules were prospectively graded using a 5-point scale. For all tumors, any changes in the echogenicity and conspicuity scores obtained at t0, t1, and t2 were evaluated. The degree of intratumoral uptake of iodized oil was categorized as compact or noncompact based on unenhanced computed tomographic images. Within each group, the sequential changes in the echogenicity and conspicuity were analyzed. Cross-sectional comparisons of the echogenicity and conspicuity at each time point between the two groups were also made. RESULTS: Overall, the lesion echogenicity and conspicuity at t1 increased compared with those at t0 (P < .05). Thereafter, both the echogenicity and conspicuity at t2 decreased compared with those at t1 (P < .05). There were 41 HCC nodules with compact iodized oil uptake and 29 with noncompact uptake. Significant sequential changes in the echogenicity (increase at t1 followed by decrease at t2) were noted in both groups, but only the compact group showed a significant change in conspicuity. In a cross-sectional comparison, the compact group showed higher scores for both echogenicity and conspicuity than the noncompact group at both t1 and t2 (P < .05). CONCLUSIONS: The echogenicity and conspicuity of HCC are increased immediately after TACE. These effects are significantly diminished 2 to 4 days after TACE.

Life-threatening late hemorrhage due to superior thyroid artery dissection after anterior cervical discectomy and fusion.

STUDY DESIGN: Case report. OBJECTIVE: The object of this report is to identify causes of late bleeding after anterior cervical discectomy and to suggest an optimal management plan. SUMMARY OF BACKGROUND DATA: The anterior discectomy and fusion is one of the most common spine procedures for cervical disc disease. Although this procedure has a low postoperative morbidity rate, rarely fatal vascular complications occur, the majority of which can be predicted intraoperatively. However, causes of unpredicted delayed bleeding are not fully understood. METHODS: We reviewed the hospital charts and radiographs of a patient who underwent coil embolization for late bleeding after anterior cervical discectomy with fusion (ACDF). RESULTS: A 33-year-old man underwent ACDF for cervical discs at C3-C4 and C4-C5. Intraoperatively, there was no major bleeding and the operation was completed after meticulous hemostasis. The patient was discharged 6 days after surgery without complications. However, at 16 days after surgery, the patient revisited the emergency room with sudden progressive neck swelling and accompanying respiratory difficulty. Because the neck swelling was rapidly progressing, the wound was opened in the intensive care unit under local anesthesia due to suspicion of hematoma. After evacuating the hematoma, we encountered active bleeding, which was controlled with gauze packing, but we were unable to identify the bleeding focus. After intubation, emergency right common carotid angiography was performed. Dissection of the right superior thyroid artery with active bleeding was identified, and this was promptly embolized with coils. After angiographic intervention, the remnant hematoma was removed in an operating room. The patient was discharged 5 days later without complication. CONCLUSION: This is the first report that shows late hemorrhage due to superior thyroid artery dissection after ACDF. This case cautions that intraoperative injury to an artery, unrecognized at operation, may cause late hemorrhage.

Targeted sonography for small hepatocellular carcinoma discovered by CT or MRI: factors affecting sonographic detection.

OBJECTIVE: The purpose of this study was to evaluate the detection rate of targeted sonography for small (

Hepatocellular carcinoma in liver transplantation candidates: detection with gadobenate dimeglumine-enhanced MRI.

OBJECTIVE: The purpose of this study was to retrospectively evaluate the diagnostic performance of dynamic gadobenate dimeglumine-enhanced MRI with explant pathologic correlation in the detection of hepatocellular carcinoma (HCC) in patients undergoing liver transplantation. MATERIALS AND METHODS: Forty-seven patients (28 men, 19 women; mean age, 49 years) underwent dynamic gadobenate dimeglumine-enhanced MRI within 3 months before primary liver transplantation. Dynamic imaging was performed before (unenhanced) and after (hepatic arterial, portal venous, equilibrium, and 1-hour delayed phases) IV bolus administration of gadobenate dimeglumine at 0.1 mmol/kg body weight. Retrospective image analysis to detect HCC nodules was performed independently by two abdominal radiologists who had no pathologic information. On a per-nodule basis, the sensitivity and positive predictive value were calculated for the two observers. Sensitivity and specificity in the diagnosis of HCC also were evaluated. Fisher's exact test was performed to determine whether there was a detection difference between HCC nodules 1 cm in diameter or larger and nodules smaller than 1 cm and to evaluate the differences in causes of false-positive MRI findings based on lesion size (>or= 1 cm vs < 1 cm). RESULTS: Twenty-seven patients had 41 HCCs. In HCC detection, gadobenate dimeglumine-enhanced MRI had a sensitivity of 85% (35 of 41 HCCs) and a positive predictive value of 66% (35 of 53 readings) for observer 1 and a sensitivity of 80% (33 of 41 HCCs) and a positive predictive value of 65% (34 of 52 readings) for observer 2. For both observers, sensitivity in the detection of HCCs 1 cm in diameter and larger (91-94%) was significantly different (p < 0.05) from that in detection of HCCs smaller than 1 cm (29-43%). Nonneoplastic arterial hypervascular lesions more often caused false-positive diagnoses of lesions smaller than 1 cm in diameter (80-86%) on MR images than of those 1 cm in diameter and larger (0-25%). The difference was statistically significant (p < 0.05) for both observers. In diagnosis, gadobenate dimeglumine-enhanced MRI had a sensitivity of 87% (20 of 23 patients) and a specificity of 79% (19 of 24 patients) for both observers. CONCLUSION: Dynamic gadobenate dimeglumine-enhanced MRI has a sensitivity of 80-85% and a positive predictive value of 65-66% in the detection of HCC. The technique, however, is of limited value for detecting and characterizing lesions smaller than 1 cm in diameter.

Radiofrequency ablation of hepatocellular carcinoma: can subcapsular tumors be safely ablated?

OBJECTIVE: Our purpose was to retrospectively evaluate percutaneous radiofrequency ablation of unifocal subcapsular hepatocellular carcinoma (HCC) in comparison with nonsubcapsular tumors with regard to the technical and clinical outcomes. MATERIALS AND METHODS: A total of 42 patients (23 men and 18 women; age range, 22-83 years) with unifocal HCC underwent percutaneous radiofrequency ablation as their sole interventional treatment between May 1998 and August 2003. Subcapsular tumors were selected for ablation if there was no large exophytic component, and they were ablated through an indirect puncture, a gradual increase in radiofrequency power output, and needle track ablation. Technical effectiveness after single-session radiofrequency ablation, complications, local tumor progression, overall survival, and event-free survival rates were compared between the two groups. RESULTS: There were 15 patients with subcapsular HCC and 27 patients with nonsubcapsular HCC. The technical effectiveness was 93% (14/15) in the subcapsular HCC group and 96% (26/27) in the nonsubcapsular group (p > 0.99), complication rates were 0% (0/15) and 7.4% (2/27) (p = 0.53), and rates of local tumor progression were 21% (3/14) and 15% (4/26) (p = 0.68), respectively. No needle track or peritoneal seeding was found in either group. No significant differences were found in overall survival (3 years: 60% vs 56%; p = 0.78) and event-free survival rates (3 years: 59% vs 48%; p > 0.99) between the two groups. CONCLUSION: Radiofrequency ablation of subcapsular HCC can be comparable to that of nonsubcapsular HCC with regard to the technical and clinical outcomes when there is proper patient selection and an optimized technique is used.

Intraoperative triple antenna hepatic microwave ablation.

OBJECTIVE: Microwave ablation is emerging as a new treatment option for patients with unresectable hepatic malignancies. This two-center study shows the results of a phase 1 clinical trial of patients with known hepatic masses who underwent synchronous triple antenna microwave ablation before elective hepatic resection. SUBJECTS AND METHODS: Intraoperative microwave ablation was performed before hepatic resection. Hepatic lesions were targeted using real-time intraoperative sonography with three microwave antennas positioned in a triangular configuration. Microwave ablation was performed at 45 W for 10 minutes. Hepatic resection was then completed in the standard fashion. Gross specimens were sectioned and measured to determine tumor and ablation sizes. Representative areas were stained with H and E stain and vital histochemical nicotinamide adenine dinucleotide (NADH) stain. RESULTS: Ten patients with a mean age of 64 years (range, 48-79 years) were treated. Tumor histology included colorectal carcinoma metastases and hepatocellular carcinoma. The mean maximal tumor diameter was 4.4 cm (range, 2.0-5.7 cm). The mean maximal ablation diameter was 5.5 cm (range, 5.0-6.5 cm), while the average ablation zone volume was 50.8 cm3 (range, 30.3-65.5 cm3). Gross and microscopic examinations of areas after microwave ablation showed clear coagulation necrosis, even surrounding large hepatic vessels (> 3 mm in diameter). A marked thermallike effect was observed with maximal intensity closest to the antenna sites. NADH staining confirmed the uniform absence of viable tumor in the ablation zone. CONCLUSION: This study shows the feasibility of using multiple microwave antennas simultaneously in the treatment of liver tumors intraoperatively. Additional percutaneous studies are currently under way to investigate the safety and efficacy in treating nonsurgical candidates.