Spontaneous Regression of Hepatocellular Carcinoma with Multiple Lung Metastases: A Case Report and Review of the Literature

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare event. Here we present a case of spontaneous regression of metastatic HCC. A 53-year-old man with hepatitis C and alcoholic cirrhosis was found to have a large liver mass consistent with HCC based on its radiographic features. Imaging also revealed left portal and hepatic vein thrombosis, as well as multiple lung nodules concerning for metastases. Approximately 2 months after the initial diagnosis, both the primary liver lesion and the lung metastases decreased in size and eventually resolved without any intervention. Thereafter, the left hepatic vein thrombus progressed into the inferior vena cava and the right atrium, and the patient died due to right heart failure. In this case report and literature review, we discuss the potential mechanisms for and review the literature on spontaneous regression of metastatic HCC.

Meta-analysis of transcriptome data identifies a novel 5-gene pancreatic adenocarcinoma classifier

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is largely incurable due to late diagnosis. Superior early detection biomarkers are critical to improving PDAC survival and risk stratification.

EXPERIMENTAL DESIGN

Optimized meta-analysis of PDAC transcriptome datasets identified and validated key PDAC biomarkers. PDAC-specific expression of a 5-gene biomarker panel was measured by qRT-PCR in microdissected patient-derived FFPE tissues. Cell-based assays assessed impact of two of these biomarkers, TMPRSS4 and ECT2, on PDAC cells.

RESULTS

A 5-gene PDAC classifier (TMPRSS4, AHNAK2, POSTN, ECT2, SERPINB5) achieved on average 95% sensitivity and 89% specificity in discriminating PDAC from non-tumor samples in four training sets and similar performance (sensitivity = 94%, specificity = 89.6%) in five independent validation datasets. This classifier accurately discriminated PDAC from chronic pancreatitis (AUC = 0.83), other cancers (AUC = 0.89), and non-tumor from PDAC precursors (AUC = 0.92) in three independent datasets. Importantly, the classifier distinguished PanIN from healthy pancreas in the PDX1-Cre;LSL-KrasG12D PDAC mouse model. Discriminatory expression of the PDAC classifier genes was confirmed in microdissected FFPE samples of PDAC and matched surrounding non-tumor pancreas or pancreatitis. Notably, knock-down of TMPRSS4 and ECT2 reduced PDAC soft agar growth and cell viability and TMPRSS4 knockdown also blocked PDAC migration and invasion.

CONCLUSIONS

This study identified and validated a highly accurate 5-gene PDAC classifier for discriminating PDAC and early precursor lesions from non-malignant tissue that may facilitate early diagnosis and risk stratification upon validation in prospective clinical trials. Cell-based experiments of two overexpressed proteins encoded by the panel, TMPRSS4 and ECT2, suggest a causal link to PDAC development and progression, confirming them as potential therapeutic targets.

Implications of aligning full registration of doctors with medical school graduation: a qualitative study of stakeholder perspectives

OBJECTIVES

The Shape of Training report recommended that full registration is aligned with medical school graduation. As part of a General Medical Council-funded study about the preparedness for practice of UK medical graduates, we explored UK stakeholders' views about this proposal using qualitative interviews (30 group and 87 individual interviews) and Framework Analysis.

SETTING

Four UK study sites, one in each country.

PARTICIPANTS

185 individuals from eight stakeholder groups: (1) foundation year 1 (F1) doctors (n=34); (2) fully registered trainee doctors (n=33); (3) clinical educators (n=32); (4) undergraduate/postgraduate Deans, and Foundation Programme Directors (n=30); (5) other healthcare professionals (n=13); (6) employers (n=7); (7) policy and government (n=11); (8) patient and public representatives (n=25).

RESULTS

We identified four main themes: (1) The F1 year as a safety net: patients were protected by close trainee supervision and 'sign off' to prevent errors; trainees were provided with a safe environment for learning on the job; (2) Implications for undergraduate medical education: if the proposal was accepted, a 'radical review' of undergraduate curricula would be needed; undergraduate education might need to be longer; (3) Implications for F1 work practice: steps to protect healthcare team integration and ensure that F1 doctors stay within competency limits would be required; (4) Financial, structural and political implications: there would be cost implications for trainees; clarification of responsibilities between undergraduate and postgraduate medical education would be needed. Typically, each theme comprised arguments for and against the proposal.

CONCLUSIONS

A policy change to align the timing of full registration with graduation would require considerable planning and preliminary work. These findings will inform policymakers' decision-making. Regardless of the decision, medical students should take on greater responsibility for patient care as undergraduates, assessment methods in clinical practice and professionalism domains need development, and good practice in postgraduate supervision and support must be shared.

Stereotactic Body Radiotherapy (SBRT) Reirradiation for Recurrent Pancreas Cancer

OBJECTIVES

After adjuvant or definitive radiation for pancreas cancer, there are limited conventional treatment options for recurrent pancreas cancer. We explored the role of (Stereotactic Body Radiotherapy) SBRT for reirradiation of recurrent pancreas Cancer.

METHODS

This is a retrospective study of patients reirradiated with SBRT for recurrent pancreas cancer. All patients were deemed unresectable and treated with systemic therapy. Fiducial gold markers were used. CT simulation was performed with oral and IV contrast and patients were treated with respiratory motion tracking in the Cyberknife(TM) system.

RESULTS

30 patients (17 men and 13 women) with a median age of 67 years were included in the study. The median target volume was 41.29cc. The median prescription dose was 25Gy (24-36Gy) in a median of 5 fractions prescribed to a mean 78% isodose line. The median overall survival was 14 months. The 1 and 2 year local control was 78%. The worst toxicity included 3/30(10%) Grade III acute toxicity for pain, bleeding and vomiting. There was 2/30 (7%) Grade III long-term bowel obstructions.

CONCLUSIONS

SBRT can be a useful and tolerable option for patients with recurrent pancreas cancer after prior radiation.

Abstract B118: A phase 1, open-label multiple dose escalation trial to determine safety and tolerability of once daily OPB-111077 in subjects with advanced cancer

Background: OPB-111077 is a new chemical entity with anticancer activity in vitro and in human tumor xenograft models. The compound modulates STAT3 phosphorylation but has no marked effect on activity of any of 69 tested human tyrosine or serine/threonine kinases. This P1 study evaluated safety, pharmacokinetics, and antitumor activity of OPB-111077 in subjects with advanced cancers.

Methods: Primary objectives determined safety, tolerability, and maximum tolerated dose (MTD) of OPB-111077 given orally once daily to subjects with advanced cancer. Secondary objectives included pharmacokinetics (PK) and antitumor activity. In the first 2 cycles of dose escalation, Day 1 dose was followed by 2 days off study therapy for PK. The starting dose was 100 mg once daily. Single subject cohorts with dose level doublings were studied until the first ≥ Grade 2 AE that was possibly drug-related. Then a 3+3 design was used. After MTD determination, expansion cohorts were opened for subjects with malignancies possibly susceptible to inhibition by OPB-111077, including breast, cervical, colorectal, gastric, kidney, myeloma, non-small cell lung, non-Hodgkin's lymphoma, ovarian, and prostate cancers, as well as “rare tumors” for which STAT3 inhibition might generate clinical activity.

Results: Overall 145 subjects received OPB-111077. Mean age was 61 years (range 21-88), and 51% of subjects were female. Dose escalation occurred in 18 subjects. Four DLTs were observed: 2 at 400 mg QD (G3 nausea/vomiting), and 2 at 300 mg QD (G3 vertigo and G3 nausea/vomiting). The MTD was 250 mg QD. All subjects recovered from DLTs after drug discontinuation. Adverse events (AEs) that may be attributable to OPB-111077 include nausea (71%), vomiting (46%), fatigue (44%), dizziness/vertigo (26%), and hypothyroidism (19%). Most AEs were CTCAE Grades 1 or 2 and manageable with supportive treatment. OPB-111077 exposures increase dose proportionally and linearly with increasing single and multiple doses up to 250 mg. Median time to peak plasma concentration (tmax) is about 4 hours. Mean maximum plasma concentration (Cmax) is 16 μmol/L and mean trough concentration is 6 μmol/L after multiple doses of 250 mg QD. Terminal half-life is about 23 hours and steady state was reached by about 1 week. The major metabolites in plasma are pharmacologically inactive and unlikely to contribute to efficacy. Administration with a high fat meal did not significantly alter OPB-111077 bioavailability. Expansion cohorts enrolled 127 subjects, including NSCLC (13), breast (13), ovarian (11), kidney (11), colorectal (10), prostate (8), lymphoma (8), gastric (7), cervical (3) cancers, and myeloma (1). Rare tumors with STAT rationale included sarcomas (13), neuroendocrine tumors (7), squamous cell carcinomas (5), other carcinomas (12), and other malignant tumors (5). One RECIST Partial Response occurred in a subject with Diffuse Large B Cell Lymphoma. In addition, 7 subjects with had stable disease for at least 8 treatment cycles, including gastric (2), cholangiocarcinoma, kidney, prostate, K-Ras mutant colon cancer, and esthesioneuroblastoma.

Conclusions: OPB-111077 can be given safely and achieves clinically active drug levels in humans. Single agent clinical activity was observed. Translational work is ongoing to determine factors driving clinical activity

Citation Format: Gregory Cote, Kyriakos Papadopoulos, Amita Patnaik, Drew Rascoe, Lon Smith, Andrea Bullock, Keith Flaherty, Geoffrey Shapiro, Jordan Berlin, Manish Monga, Thomas Habermann, Thomas Witzig, Chester Lin, Lin-Feng Tsai, Agnes Elekes, Naoto Ohi, Kunihiko Tatsumi, Anthony Tolcher. A phase 1, open-label multiple dose escalation trial to determine safety and tolerability of once daily OPB-111077 in subjects with advanced cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B118.

Stereotactic Body Radiotherapy (SBRT) for Intrahepatic and Hilar Cholangiocarcinoma

Background: Unresectable intrahepatic and hilar cholangiocarcinomas carry a dismal prognosis. Systemic chemotherapy and conventional external beam radiation and brachytherapy have been used with limited success. We explored the use of stereotactic body radiotherapy (SBRT) for these patients.

Methods: Patients with unresectable intrahepatic or hilar cholangiocarcinoma or those with positive margins were included in this study. Systemic therapy was used at the discretion of the medical oncologist. The Cyberknife^TM stereotactic body radiotherapy system used to treat these patients. Patients were treated with three daily fractions. Clinical and radiological follow-up were performed every three months.

Results: 34 patients (16 male and 18 female) with 42 lesions were included in this study. There were 32 unresectable tumors and two patients with resected tumors with positive margins. The median SBRT dose was 30Gy in three fractions. The median follow-up was 38 months (range 8-71 months). The actuarial local control rate was 79%. The median overall survival was 17 months and the median progression free survival was ten months. There were four Grade III toxicities (12%), including duodenal ulceration, cholangitis and liver abscess.

Conclusions: SBRT is an effective and reasonably safe local therapy option for unresectable intrahepatic or hilar cholangiocarcinoma.

Abstract PR07: Transcriptome meta-analysis identifies new 5-gene classifier for early detection of pancreatic cancer

Background: Pancreatic ductal adenocarcinoma (PDAC) is a truly devastating disease, primarily due to late diagnosis when curative resection is no longer possible and the lack of accurate early detection biomarkers. Therefore, increasing PDAC survival depends heavily on improving the accuracy and effectiveness of early PDAC detection.

Methods:Key PDAC biomarkers were identified through an optimized meta-analysis strategy of raw data in 4 PDAC transcriptome datasets (training sets). Application of identical normalization and statistical testing procedures for each dataset generated a list of differentially expressed genes by empirical Bayes moderated t-statistic. The top ranking PDAC-specific genes from this list that were consistently differentially expressed in these training sets were used for developing a classifier for PDAC. The biomarker panel with the highest sensitivity and specificity in the training sets was validated for diagnostic performance in nine independent validation datasets. A subset of genes in the panel were evaluated by immunohistochemistry (IHC) in human PDAC tissue sections. Cell based assays assessed the effect of two genes on PDAC migration and invasion.

Results and Conclusions: A 5-gene classifier panel was identified that disntinguished between PDAC and normal pancreas with high sensitivity, specificity and accuracy in the four training sets. Validation of this 5-gene predictor in 9 independent test sets confirmed the diagnostic accuracy to not only discriminate accurately between PDAC and healthy controls, but also between pancreatitis and PDAC. IHC analysis of two of the proteins encoded by the panel confirmed enhanced expression in PDAC cells. Cell-based experiments demonstrated that both proteins enhance migration and invasion of PDAC cells as well as soft agar growth, suggesting a causal link to PDAC development and progression. The immediate clinical utility upon further prospective validation of this PDAC biomarker panel will be accurate PDAC diagnosis in patients with pancreatic abnormalities on imaging, risk stratification and evaluation of the risk of malignancy in pancreatic cysts.

This abstract is also presented as Poster B26.

Citation Format: Manoj Bhasin, Octavian Bucur, Ken Ndebele, Jessica Plati, Andrea Bullock, Xuesong Gu, Eduardo Castan, Robert Najarian, Jen Jen Yeh, Channing Der, Jon Cody Haines, Karl Ruping, Rebecca Miksad, Roya Khosravi-Far, Towia Aron Libermann. Transcriptome meta-analysis identifies new 5-gene classifier for early detection of pancreatic cancer. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Innovations in Research and Treatment; May 18-21, 2014; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2015;75(13 Suppl):Abstract nr PR07.

Abstract LB-173: Early detection of pancreatic cancer using a new 5-gene classifier

Background: Largely due to late diagnosis when curative resection is no longer possible, Pancreatic Adenocarcinoma (PDAC) is a devastating disease marked by a mortality rate nearly equivalent to its incidence rate. While serum CA19-9 is associated with PDAC, it lacks the sensitivity and specificity needed for early and accurate diagnosis. Thus, early diagnosis of PDAC is critical to improving survival for PDAC patients and for accurate PDAC risk stratification.

Methods: We have identified key PDAC biomarkers through an optimized meta-analysis strategy of raw data (training sets). From this analysis, the top ranking genes that distinguish PDAC from normal pancreas were selected through statistical significance comparison of the consistency in differential PDAC gene expression across studies. The biomarker panel with the highest sensitivity and specificity in the training sets was chosen for assessment of predictive power in nine independent validation datasets. For a subset of genes in the panel, immunohistochemistry (IHC) analysis was performed in human PDAC and pancreatitis to validate our panel.

Results and Conclusions: We have identified a 5-gene classifier panel with specificity of 88.9% and sensitivity of 100% with an overall accuracy of 93.3% and AUC of 0.94 for discriminating PDAC from non-malignant (normal or pancreatitis) tissue. IHC analysis of two of the proteins confirmed enhanced expression in PDAC cells. Cell-based experiments demonstrated that both proteins enhance migration and invasion of PDAC cells as well as soft agar growth indicating that they may be causative in PDAC. The 5-gene predictor discriminated PDAC from healthy controls, as well as pancreatitis, with highest accuracy in nine independent validation sets. Our identified PDAC panel may facilitate early diagnosis and improve risk-stratification.

Citation Format: Manoj Bhasin, Andrea Bullock, Xuesong Gu, Octavian Bucur, Robert Najarian, Jon Cody Haines, Karl Ruping, Rebecca Miksad, Towia Libermann, Roya Khosravi-Far. Early detection of pancreatic cancer using a new 5-gene classifier. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-173. doi:10.1158/1538-7445.AM2014-LB-173

Abstract NG05: Depletion of a putatively druggable class of phosphatidylinositol kinases inhibits growth of p53 null tumors

The phosphoinositide family of lipids includes seven derivatives of phosphatidylinositol (PI) that are formed through the phosphorylation of the 3-, 4-, and 5-positions on the inositol ring. Phosphoinositides have distinct biological roles and regulate many cellular processes, including proliferation, survival, glucose uptake, and migration. Phosphoinositide kinases, phosphatases, and phospholipases spatially and temporally regulate the generation of the different phosphoinositide species, which localize to different subcellular compartments. Phosphatidylinositol-3,4,5-trisphosphate (PI-3,4,5-P3) is synthesized by phosphoinositide 3-kinase (PI3K) and serves as the plasma membrane docking site for a subset of proteins that have pleckstrin-homology (PH) domains that bind this lipid, including the serine/threonine protein kinase AKT (also known as protein kinase B or PKB). AKT is a proto-oncogene that has critical regulatory roles in insulin signaling and cancer progression. Phosphatidylinositol-4,5-bisphosphate (PI-4,5-P2) is the major substrate for Class I PI3Ks and has a significant role itself in mediating the localization of proteins to the plasma membrane and in nucleating cortical actin polymerization (1).

Until 1997 it was thought that PI-4,5-P2 was produced exclusively by phosphorylation of phosphatidylinositol-4-phosphate (PI-4-P) at the 5 position of the inositol ring, a reaction catalyzed by the Type 1 PI-4-P 5-kinases (encoded by the genes PIP5K1A, B and C). Unexpectedly, a second highly-related family of PIP kinases (called Type 2) was found to produce PI-4,5-P2 by phosphorylating the 4 position of phosphatidylinositol-5-phosphate (PI-5-P), a lipid that had been previously overlooked due to its co-migration with the much more abundant PI-4-P (2-3). The Type 2 PIP kinases are not present in yeast but are conserved in higher eukaryotes from worms and flies to mammals. Humans and mice have three distinct genes, PIP4K2A, B and C encoding enzymes called PI5P4Kα, β, and γ, respectively. The bulk of PI-4,5-P2 in most tissues is almost certainly derived from the Type 1 PIP5Ks, yet recent quantitative proteomic studies on cell lines have revealed a higher abundance of PI5P4Ks than PI4P5Ks (4). This high abundance of the Type 2 enzymes may, in part, explain why the substrate, PI-5-P is present at very low levels. While the Type 1 PIP kinases generate PI-4,5-P2 at the plasma membrane, the Type 2 kinases are located at internal membranes, including the ER, Golgi and nucleus and probably generate PI-4,5-P2 at those locations (5-8). The vast majority of PI-4,5-P2 is located at the plasma membrane and it is not clear whether the critical function of the Type 2 PIP kinases is to generate PI-4,5-P2 at intracellular sites or to maintain low levels of PI-5-P (or both).

In a previous study we generated mice in which one of the Type 2 PIP kinase genes (PIP4K2B) was deleted in the germline. These mice were viable, exhibited enhanced insulin sensitivity and enhanced insulin-dependent activation of AKT in skeletal muscle (9). Paradoxically, despite increased AKT activation the mice were smaller and had decreased adiposity on a high fat diet. Cell based assays revealed that PI5P4Kβ (encoded by PIP4K2B) becomes phosphorylated by p38 at Ser326 in response to cellular stresses, such as UV and H2O2, and that this causes inhibition of the PI5P 4-kinase activity and results in increased cellular PI-5-P levels (10). These studies suggest that the Type 2 PIP kinases mediate cellular stress responses downstream of p38 (presumably by altering the PI-5-P/PI-4,5-P2 ratio at intracellular locations) and that under conditions of low stress, these enzymes suppress the PI3K/AKT signaling pathway. It should be pointed out that the Type 2 PIP kinases are unlikely to supply PI-4,5-P2 as a substrate for PI3K since activation of AKT correlates with loss of PI5P4K activity rather than gain.

In this study we have interrogated the potential role of Type 2 PIP kinases in cancers. We found high levels of either PI5P4Kα or PI5P4Kβ enzymes or both in a number of breast cancer cell lines, and more importantly, found amplification of the PIP4K2B gene and high levels of both the PI5P4Kα and PI5P4Kβ proteins in a subset of human breast tumors. We found that knocking down the levels of both PI5P4Kα and PI5P4Kβ in a TP53 deficient breast cancer cell line blocked growth on plastic and in xenografts. This impaired growth correlated with impaired glucose metabolism and enhanced levels of reactive oxygen species (ROS) leading to senescence. The impaired glucose metabolism, despite activation of the PI3K-AKT pathway (which typically enhances glucose metabolism) was paradoxical. The results indicate that PI3K activation is not driving the ROS production, but may be an inadequate feedback attempt to restore glucose uptake and metabolism.

To assess the role of Type 2 PIP kinases in tumor formation, we generated mice with germline deletions of PIP4K2A and PIP4K2B and crossed these with TP53-/- mice and evaluated tumor formation in all the viable genotypes. We found that mice with homozygous deletion of both TP53 and PIP4K2B were not viable, indicating a synthetic lethality for loss of these two genes. Importantly, mice with the genotype PIP4K2A-/-, PIP4KB+/-, TP53-/- were viable and had a dramatic reduction in tumor formation compared to siblings that were TP53-/- and wild type for PIP4K2B and/or PIP4K2A genes. The decreased tumor incidence in the background of PIP4K2A-/-, PIP4K2B+/-, TP53-/- compared to TP53-/- alone is particularly interesting in respect to Li Fraumeni Syndrome (germline TP53 mutations). Our results indicate that expression of PI5P4Kα and/or β is critical for the growth of tumors with TP53 mutations or deletions. Thus, co-amplification of PIP4K2B with ERBB2 might explain why breast cancers in patients with Li Fraumeni syndrome show ERBB2 amplifications (HER2-positive) in over 83% of cases as opposed to 16% of age-matched patients with wild type TP53 (11).

The results that we present here suggest that PI5P4Kα and β play a critical role in mediating changes in metabolism in response to stress, and in particular ROS stress that occurs in the absence of p53. Germ-line deletion of either PIP4K2A or PIP4K2B alone resulted in mice with normal lifespans, and germ-line deletion of both PIP4K2A and PIP4K2B resulted in full-term embryos of normal size and appearance at birth, indicating that these genes do not play a major role in normal embryonic growth and development. Yet the PIP4K2A-/-, PIP4K2B-/- pups die shortly after birth, consistent with these genes having a role in mediating stress responses known to occur following birth. Importantly, germ-line deletion of both PIP4K2B and TP53 resulted in lethality while germ-line deletion of either gene alone resulted in Mendelian ratios of viable pups. Thus, the genetic studies suggest that TP53 and PIP4K2B have overlapping roles in mediating cellular responses to stress and that, while neither gene alone is essential, loss of both genes is not tolerated.

The most exciting observation from these studies in regard to potentially new therapies for p53 mutant tumors is that germ-line deletion of both alleles of PIP4K2A and one allele of PIP4K2B in the context of TP53-/- results in a viable mouse with a dramatic reduction in tumor-dependent death compared to TP53-/- mice that are wild type for PIP4K2A and B. These results (and studies of the PIP4K2A-/-, PIP4K2B+/- or PIP4K2A+/-, PIP4K2B-/- mice in the context of wild type TP53) indicate that normal tissues tolerate well the loss of three out of four alleles of the PIP4K2A and PIP4K2B genes, but that tumors are not viable in this context. PI5P4Kα and β are kinases and pharmaceutical companies have shown that it is possible to develop highly specific inhibitors of both protein kinases and lipid kinases. The synthetic lethality that we observe between TP53 loss and loss of these kinases indicates that drugs that target either the enzyme PI5P4Kβ alone or that target both PI5P4Kα and β are likely to be well-tolerated and very effective on tumors that have loss of function mutations or deletions of TP53. Our observations with BT474 cells suggest that HER2 positive tumors that have amplifications of PIP4K2B and mutations in TP53 may be particularly sensitive to PI5P4Kα,β inhibitors. The ERBB2 (Her2) amplicon on chromosome 17 is variable in size and can contain a number of cancer-related genes in addition to the ERBB2 locus. Clinically, patients who have tumors with small amplicons confined to the ERBB2 locus have the greatest benefit from ERBB2-directed therapies such as Trastuzumab, while tumors with wider ERBB2 amplicons have poor responses, suggesting co-amplification of genes that contribute to Trastuzumab resistance (11). PIP4K2B, which is located in a chromosomal region (17q12) close to ERBB2, may be a candidate for an adjacent co-amplified gene that confers Trastuzumab resistance, and, conversely, concomitant inhibition of ERBB2 and PIP4K2B could be a highly effective treatment option for ERBB2 (Her2) positive tumors that are p53-mutant and PIP4K2B-amplified.

References

1. Cantley, L.C. The phosphoinositide 3-kinase pathway. Science 2002;296:1655-1657.

2. Rameh, L.E., and Cantley, L.C. The role of phosphoinositide 3-kinase lipid products in cell function. J Biol Chem 1999;274:8347-8350.

3. Rameh, L.E., Tolias, K.F., Duckworth, B.C., and Cantley, L.C. A new pathway for synthesis of phosphatidylinositol-4,5-bisphosphate. Nature 1997;390:192-196.

4. Nagaraj, N., Wisniewski, J.R., Geiger, T., Cox, J., Kircher, M., Kelso, J., Paabo, S., and Mann, M. Deep proteome and transcriptome mapping of a human cancer cell line. Mol Syst Biol 2011;7: 548.

5. Fruman, D.A., Meyers, R.E., and Cantley, L.C. Phosphoinositide kinases. Annu Rev Biochem 1998;67:481-507.

6. Sarkes, D., and Rameh, L.E. A novel HPLC-based approach makes possible the spatial characterization of cellular PtdIns5P and other phosphoinositides. Biochem J 2010;428:375-384.

7. Schaletzky, J., Dove, S.K., Short, B., Lorenzo, O., Clague, M.J., and Barr, F.A. Phosphatidylinositol-5-phosphate activation and conserved substrate specificity of the myotubularin phosphatidylinositol 3-phosphatases. Curr Biol 2003;13:504-509.

8. Walker, D.M., Urbe, S., Dove, S.K., Tenza, D., Raposo, G., and Clague, M.J. Characterization of MTMR3. an inositol lipid 3-phosphatase with novel substrate specificity. Curr Biol 2001;11:1600-1605.

9. Lamia, K.A., Peroni, O.D., Kim, Y.B., Rameh, L.E., Kahn, B.B., and Cantley, L.C. Increased insulin sensitivity and reduced adiposity in phosphatidylinositol 5-phosphate 4-kinase beta-/- mice. Mol Cell Biol 2004;24:5080-5087.

10. Jones, D.R., Bultsma, Y., Keune, W.J., Halstead, J.R., Elouarrat, D., Mohammed, S., Heck, A.J., D'Santos, C.S., and Divecha, N. Nuclear PtdIns5P as a transducer of stress signaling: an in vivo role for PIP4Kbeta. Mol Cell 2006;23:685-695.

11. Morrison, L.E., Jewell, S.S., Usha, L., Blondin, B.A., Rao, R.D., Tabesh, B., Kemper, M., Batus, M., and Coon, J.S. Effects of ERBB2 amplicon size and genomic alterations of chromosomes 1, 3, and 10 on patient response to trastuzumab in metastatic breast cancer. Genes Chromosomes Cancer 2007;46:397-405.

Citation Format: Brooke M. Emerling, Jonathan B. Hurov, George Poulogiannis, Rayman Choo-Wing, Gerburg M. Wulf, Hye-Seok Shim, Katja A. Lamia, Lucia E. Rameh, Xin Yuan, Andrea Bullock, Gina M. DeNicola, Jiaxi Song, Sabina Signoretti, Lewis C. Cantley. Depletion of a putatively druggable class of phosphatidylinositol kinases inhibits growth of p53 null tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr NG05. doi:10.1158/1538-7445.AM2014-NG05

Imitation in Mediation: Effects of the Duration of Mimicry on Reaching Agreement

We conducted 2 experiments (N = 180 participants in Study 1 and N = 102 in Study 2) to examine the effect of imitation shown by a mediator towards negotiators who were on opposing sides in regard to a financial decision being made by a fictitious company. Contrary to what was expected, data in the first study showed that, when the mediator imitated the negotiator during the first 5 minutes of an interview, this was insufficient to predispose negotiators to be more likely to reach an agreement with one another. The results in the second study showed that imitation conducted over a longer time and repeated more often during negotiations predisposed opposing parties to be more likely to agree with one another. Applications and limitations of these studies are discussed.

Depletion of a putatively druggable class of phosphatidylinositol kinases inhibits growth of p53-null tumors

Here, we show that a subset of breast cancers express high levels of the type 2 phosphatidylinositol-5-phosphate 4-kinases α and/or β (PI5P4Kα and β) and provide evidence that these kinases are essential for growth in the absence of p53. Knocking down PI5P4Kα and β in a breast cancer cell line bearing an amplification of the gene encoding PI5P4K β and deficient for p53 impaired growth on plastic and in xenografts. This growth phenotype was accompanied by enhanced levels of reactive oxygen species (ROS) leading to senescence. Mice with homozygous deletion of both TP53 and PIP4K2B were not viable, indicating a synthetic lethality for loss of these two genes. Importantly however, PIP4K2A(-/-), PIP4K2B(+/-), and TP53(-/-) mice were viable and had a dramatic reduction in tumor formation compared to TP53(-/-) littermates. These results indicate that inhibitors of PI5P4Ks could be effective in preventing or treating cancers with mutations in TP53.

The effect of priming with a love concept on blood donation promise

This field study on blood donor behavior tests the effectiveness of semantic priming on donor intention and commitment. Using face-to-face interactions, participants were primed with the concept of love and solicited to promise blood to the French National Blood Bank. Results showed a significant effect on willingness to donate blood and on donor commitment. The relatively simple and easily implemented technique used in this study could be of interest in improving performance of recruitment and retention campaigns.

Tumor necrosis on magnetic resonance imaging correlates with aggressive histology and disease progression in clear cell renal cell carcinoma

OBJECTIVE

The study objective was to correlate the magnetic resonance imaging (MRI) features of clear cell renal cell carcinoma (ccRCC) with the histopathologic features and disease progression.

METHODS

Institutional review board approval for this retrospective study was obtained; patient consent was not required. The initial staging MRI scans of 75 patients with histologically confirmed ccRCC were retrospectively reviewed. The imaging was assessed by 2 radiologists for the presence of tumor necrosis, cystic degeneration, intracellular fat, hemorrhage, retroperitoneal collaterals, and renal vein thrombosis. Quantitative analysis for the MRI presence of intracellular lipid within tumors was performed. MRI findings were correlated with histopathologic findings of clear cell percentage, alveolar and tubular growth pattern, and disease progression. Statistical associations were evaluated with nonparametric univariable analyses and multivariable logistic regression models.

RESULTS

Correlation between MRI and histopathologic features was performed in 75 patients, whereas follow-up data were available for progression analysis in 68 patients. The presence of tumor necrosis, retroperitoneal collaterals, and renal vein thrombosis on MRI was significantly associated with a low percentage of tumor cells with clear cytoplasm (P < .01) and metastatic disease at presentation or disease progression (P < .01). At multivariable analysis, necrosis remained the only feature statistically associated with disease progression (P = .03; adjusted odds ratio, 27.7; 95% confidence interval, 1.4-554.7 for reader 1 and P = .02; adjusted odds ratio, 29.3; 95% confidence interval, 1.7-520.8 for reader 2).

CONCLUSIONS

Necrosis in ccRCC on MRI correlates with the histopathologic finding of lower percentage of tumor cells with clear cytoplasm and is a poor prognostic indicator irrespective of tumor size.