Citations

SummaryPatients with early stage diffuse large B‐cell lymphoma (DLBCL) receive RCHOP (rituximab cyclophosphamide, doxorubicin, vincristine, prednisone) alone or with involved field radiotherapy (IFRT). Anti‐CD20 radioimmunotherapy (RIT) delivers radiation to microscopic sites outside of known disease. This phase II study aimed to achieve a functional complete response (CR) rate of ≥75% to RCHOP and 90Yttrium‐ibritumomab tiuxetan RIT. Patients with stages I/II DLBCL received 4–6 cycles of RCHOP followed by RIT [14·8 MBq/kg (0·4 mCi/kg)]; patients with positron emission tomographypositive sites of disease after RCHOP/RIT received 30 Gy IFRT. Of the 62 patients enrolled; 53 were eligible. 42% (22/53) had stage I/IE; 58% (31/53) stage II/IIE. After RCHOP, 79% (42/53) were in CR/unconfirmed CR. Forty‐eight patients proceeded to RIT. One partial responder after RIT received IFRT and achieved a CR. The best response after RCHOP + RIT in all 53 patients was a functional CR rate of 89% (47/53; 95% confidence interval: 77–96%). With a median follow‐up of 5·9 years, 7 (13%) patients have progressed and 4 (8%) have died (2 with DLBCL). At 5 years, 78% of patients remain in remission and 94% are alive. Chemoimmunotherapy and RIT is an active regimen for early stage DLBCL patients. Eighty‐nine percent of patients achieved functional CR without the requirement of IFRT. This regimen is worthy of further study for early stage DLBCL in a phase III trial.

Abstract microRNAs (miRNAs) regulate gene expression and some have been shown to function as either oncogenes or tumor suppressors (oncomirs). Changes in miRNA expression have been observed in many human cancers but their role in endometrioid endometrial cancer (EEC) remains poorly understood. We studied the expression of 365 human miRNAs using Taqman low density arrays in 98 EECs as well as 60 normal endometria. Potentially interesting miRNAs were then validated by qRT-PCR. Expression of highly deregulated miRNAs on malignant cell properties was also examined in vitro using pre-/anti-miRNA transfection. Predicted mRNA targets for the miRNA of interest were also verified. We identified 16 significantly deregulated miRNAs in EEC and 7 of these are reported for the first time. Of these, miR-7, miR-194 and miR-449b knockdown and miR-204 induction repressed migration, invasion and extracellular matrix-adhesion in HEC1A endometrial cancer cells. For the cancer progression dysregulation of the expression of miR204 mediates migration and invasion of endometrial cancer by regulating FOXC1-related miR-204, FOXC1 was determined as its target gene possessing two miR-204-binding sites at the 3’-untranslated region. FOXC1 expression was inversely related to miR-204 expression in EEC. Functional analysis also revealed the involvement of FOXC1 in migration of HEC1A cells. We have identified dysfunctional miRNAs in endometrial cancer and elucidated the crucial role of miR-204-FOXC1 interaction in endometrial cancer progression. This work provides insight into miRNA-based diagnostic and therapeutic approaches for endometrial cancers.

Abstract Background: MRX34 is a liposome-formulated double-stranded mimic of tumor suppressor microRNA-34 (miR-34), which is lost or expressed at reduced levels in many solid and hematologic malignancies. miR-34 functions in the p53 tumor suppressor pathway and regulates the expression of more than 20 cancer-related genes including BCL2, E2F3, HDAC1, MET, MEK1, CDK4/6, PDGFR-ɑ, SIRT1, WNT1/3, NOTCH-1, β-catenin, CD44, Nanog and AXL. miR-34 also suppresses stem-like properties in cancer cells and sensitizes cancer cells to cytotoxic and targeted therapies. A multicenter phase I clinical trial of MRX34 is being conducted in patients with unresectable hepatocellular carcinoma or metastatic cancer with liver involvement. Methods: Eligible patients are enrolled in a standard 3 + 3 dose escalation study at MRX34 starting dose of 10 mg/m2, administered IV on days 1, 4, 8, 11, 15, and 18 of 28-day cycles. Dexamethasone premedication was added after the first 2 dose levels. The primary objective is to determine the RP2D, and secondary objectives include assessments of safety, PK and objective response rate (ORR). Response is evaluated by CT/MRI every 8 weeks. Once RP2D has been established, expansion cohort will be treated at the RP2D, with specific focus on determining biological response in tumor biopsy material. The latter will include assessing tumor uptake of miR-34 mimic and down-regulation of target gene expression as was observed in animal models of cancer. Results: Twenty-five patients received study drug, and enrollment is currently ongoing at the 5th dose level (70 mg/m2) and MTD has not been reached. There were 18 Caucasians, 15 males, with a median age of 62.5 years and a median of 4 prior treatments. Liposomal formulation-associated infusion reactions have been observed as characterized by the following treatment emergent adverse events (AEs) out of 20 patients: fever (13), chills (12), fatigue (12), thrombocytopenia (8), diarrhea (8), back/flank pain (6), nausea (6), and neutropenia (4). Most common Gr 3/4 AEs were neutropenia (4), thrombocytopenia (3), fatigue (2), AST/ALT elevation (4) and back/flank pain (2). Addition of pre-dose dexamethasone with higher dose levels ameliorated infusion reactions. One patient died on study from disease progression. One dose-limiting toxicity was observed at the 2nd dose level (20 mg/m2; Gr 3 acute kidney injury associated with nausea, vomiting, diarrhea and dehydration) and one at the 5th dose level (70 mg/m2; Gr 3 increased AST). Conclusions: MRX34 has a manageable safety profile in patients with unresectable primary liver cancer or metastatic cancer with liver involvement. Determination of the R2PD, assessment of clinical response, and analyses of molecular markers are ongoing. Citation Format: Muhammad Shaalan Beg, Mitesh Borad, Jasgit Sachdev, David S. Hong, Susan Smith, Andres Bader, Jay Stoudemire, Sinil Kim, Andrew Brenner. Multicenter phase I study of MRX34, a first-in-class microRNA miR-34 mimic liposomal injection. [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 CT327. doi:10.1158/1538-7445.AM2014-CT327

Abstract Metastatic invasion of tumors into peripheral tissues is known to rely upon protease-mediated degradation of the surrounding stroma. This remodeling process is dependent upon complex, actin-based specializations of the plasma membrane termed “invadopodia” that act to both sequester and release matrix metalloproteases. Here we report that cells of mesenchymal origin, including fibroblasts, pancreatic stellate cells, and tumor-associated fibroblasts, degrade substantial amounts of surrounding matrix by a mechanism independent of conventional invadopodia. First, as tumor cell-derived invadopodia are dependent upon the action of the GTPase Dyn2, loss of Dyn2 function inhibits invadopodia-based matrix degradation by pancreatic tumor cells. In surprising contrast, we have found that loss of Dyn2 function in mesenchymal cells does not inhibit degradation, but actually leads to a marked increase. Second, these degradative sites lack the punctate shape of conventional invadopodia but are instead spread along the cell base and are reticular and/or fibrous in character. Third, inhibition of either Src or Cdc42 function, known to drive invadopodia formation, had no effect on the mesenchymal matrix degradation induced by loss of Dyn2. Taken together, these data indicate that this mechanism of degradation is independent of classical invadopodial degradation. To define the mechanistic processes that differ between tumor and stromal cell types, we screened for matrix metalloprotease activity using zymography. An unexpected and significant upregulation of MMP2 activity in mesenchymal-derived cells upon loss of Dyn2 was observed, whereas MMP2 was nearly completely absent in the tumor cells. Further, loss of Dyn2 resulted in an upregulation of surface-bound MT1-MMP, known to activate MMP2. In contrast, loss of Dyn2 in the pancreatic tumor cells reduced surface levels of MT1-MMP. Thus, in mesenchymal cells, loss of Dyn2 induces retention of MT1-MMP at the surface, leading to large scale matrix degradation through an MT1-MMP/MMP2-dependent mechanism. Excitingly, co-culture invasion experiments demonstrate that the matrix degradation induced in these stromal fibroblasts is sufficient to promote invasion by pancreatic tumor cells. These findings provide evidence for a novel matrix remodeling process conducted by mesenchymal cells that is substantially more effective than conventional invadopodia, distinct in structural organization, independent of the classical invadopodial machinery, and capable of promoting invasion by pancreatic tumor cells. Supported by NCI RO1 CA104125 to MAM. Citation Format: Hong Cao, Robbin Eppinga, Eugene Krueger, Jing Chen, Gina Razidlo, Mark A. McNiven. Differential mechanisms utilized by pancreatic tumor cells and associated fibroblasts to remodel stroma during metastatic invasion. [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 3162. doi:10.1158/1538-7445.AM2014-3162

SummaryAimsNeurodegenerative disorders are caused by progressive neuronal loss in the brain, and hence, compounds that could promote neuritogenesis may have therapeutic values. In this study, the effects of bis(heptyl)‐cognitin (B7C), a multifunctional dimer, on neurite outgrowth were investigated in both PC12 cells and primary cortical neurons.MethodsImmunocytochemical staining was used to evaluate the proneuritogenesis effects, and Western blot and short hairpin RNA assays were applied to explore the underlying mechanisms.ResultsB7C (0.1–0.5 μM) induced robust neurite outgrowth in PC12 cells, as evidenced by the neurite‐bearing morphology and upregulation of growth‐associated protein‐43 expression. In addition, B7C markedly promoted neurite outgrowth in primary cortical neurons as shown by the increase in the length of β‐III‐tubulin‐positive neurites. Furthermore, B7C rapidly increased ERK phosphorylation. Specific inhibitors of alpha7‐nicotinic acetylcholine receptor (α7‐nAChR) and MEK, but not those of p38 or JNK, blocked the neurite outgrowth as well as ERK phosphorylation induced by B7C. Most importantly, genetic depletion of α7‐nAChR significantly abolished B7C‐induced neurite outgrowth in PC12 cells.ConclusionB7C promoted neurite outgrowth through the activation of α7‐nAChR/ERK pathway, which offers novel insight into the potential application of B7C in the treatment of neurodegenerative disorders.

Preclinical studies are important in helping practitioners and device developers improve techniques and tools for endovascular treatment of intracranial aneurysms. Thus an understanding of the major animal models used in such studies is important. The New Zealand rabbit elastase induced arterial aneurysm of the common carotid artery is one of the most commonly used models in testing the safety and efficacy of new endovascular devices. In this review we discuss: (1) the various techniques used to create the aneurysm, (2) complications of aneurysm creation, (3) natural history of the arterial aneurysm, (4) histopathologic and hemodynamic features of the aneurysm, (5) devices tested using this model, and (6) weaknesses of the model. We demonstrate how preclinical studies using this model are applied in the treatment of intracranial aneurysms in humans. The model has similar hemodynamic, morphological, and histologic characteristics to human aneurysms, and demonstrates similar healing responses to coiling as human aneurysms. Despite these strengths, however, the model does have many weaknesses, including the fact that the model does not emulate the complex inflammatory processes affecting growing and ruptured aneurysms. Furthermore, the extracranial location of the model affects its ability to be used in preclinical safety assessments of new devices. We conclude that the rabbit elastase model has characteristics that make it a simple and effective model for preclinical studies on the endovascular treatment of intracranial aneurysms, but further work is needed to develop aneurysm models that simulate the histopathologic and morphologic characteristics of growing and ruptured aneurysms.

We report generation and characterization of pain‐related behavior in a minimally invasive facet joint degeneration (FJD) animal model in rats. FJD was produced by a non‐open percutaneous puncture‐induced injury on the right lumbar FJs at three consecutive levels. Pressure hyperalgesia in the lower back was assessed by measuring the vocalization response to pressure from a force transducer. After hyperalgesia was established, pathological changes in lumbar FJs and alterations of intervertebral foramen size were assessed by histological and imaging analyses. To investigate treatment options for lumber FJ osteoarthritis‐induced pain, animals with established hyperalgesia were administered with analgesic drugs, such as morphine, a selective COX‐2 inhibitor, a non‐steroidal anti‐inflammatory drug (NSAID) (ketorolac), or pregabalin. Effects were assessed by behavioral pain responses. One week after percutaneous puncture‐induced injury of the lumbar FJs, ipsilateral primary pressure hyperalgesia developed and was maintained for at least 12 weeks without foraminal stenosis. Animals showed decreased spontaneous activity, but no secondary hyperalgesia in the hind paws. Histopathological and microfocus X‐ray computed tomography analyses demonstrated that the percutaneous puncture injury resulted in osteoarthritis‐like structural changes in the FJs cartilage and subchondral bone. Pressure hyperalgesia was completely reversed by morphine. The administration of celecoxib produced moderate pain reduction with no statistical significance while the administration of ketorolac and pregabalin produced no analgesic effect on FJ osteoarthritis‐induced back pain. Our animal model of non‐open percutanous puncture‐induced injury of the lumbar FJs in rats shows similar characteristics of low back pain produced by human facet arthropathy. J. Cell. Physiol. 9999: 2837–2847, 2015. © 2015 Wiley Periodicals, Inc.

Summary A persistently positive positron emission tomography ( PET ) scan during therapy for diffuse large B‐cell lymphoma ( DLBCL ) is predictive of treatment failure. A response‐adapted strategy consisting of an early treatment change to four cycles of R‐ ICE (rituximab, ifosfamide, carboplatin, etoposide) was studied in the Eastern Cooperative Oncology Group E3404 trial. Previously untreated patients with DLBCL stage III, IV, or bulky II, were eligible. PET scan was performed after three cycles of R‐ CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) and scored as positive or negative by central review during the fourth cycle. PET ‐positive patients received four cycles of R‐ ICE , PET ‐negative patients received two more cycles of R‐ CHOP . A ≥45% 2‐year progression‐free survival ( PFS ) for mid‐treatment PET ‐positive patients was viewed as promising. Of 74 patients, 16% were PET positive, 79% negative. The PET positivity rate was much lower than the 33% expected. Two‐year PFS was 70%; 42% [90% confidence interval (CI), 19–63%] for PET ‐positives and 76% (90% CI 65–84%) for PET ‐negatives. Three‐year overall survival ( OS ) was 69% (90% CI 43–85%) and 93% (90% CI 86–97%) for PET ‐positive and ‐negative cases, respectively. The 2‐year PFS for mid‐treatment PET ‐positive patients intensified to R‐ ICE was 42%, with a wide confidence interval due to the low proportion of positive mid‐treatment PET scans. Treatment modification based on early PET scanning should remain confined to clinical trials.

BACKGROUNDNVP‐AUY922 (AUY; Luminespib) with or without bortezomib showed preclinical activity against multiple myeloma (MM) cells. This phase 1/1B study assessed NVP‐AUY922 alone and with bortezomib in patients with relapsed or refractory MM.METHODSDose escalation was guided by an adaptive Bayesian logistic regression model. In phase 1, patients who progressed after 2 to 4 prior therapies received NVP‐AUY922 intravenously once weekly. In phase 1B, patients who progressed after 2 or fewer prior therapies received NVP‐AUY922 plus bortezomib. The primary objective was to determine the maximum tolerated dose (MTD) of NVP‐AUY922.RESULTSTwenty‐four patients received NVP‐AUY922 monotherapy at doses of 8 to 70 mg/m2. One dose‐limiting toxicity (DLT) was observed (grade 3 blurred vision at 70 mg/m2); no MTD was reached. The recommended phase 2 dose was 70 mg/m2. The most frequent drug‐related adverse events (AEs) were diarrhea, nausea, and ocular toxicities. Grade 3/4 AEs were uncommon (<10%). Eight patients discontinued treatment because of AEs; 5 had ocular toxicities (≥45 mg/m2). The best response was stable disease in 66.7% of the patients. There were no partial or complete responses. Five patients received NVP‐AUY922 (which was started at 50 mg/m2) plus bortezomib (1.3 mg/m2). Three of these patients experienced DLT. No further dose escalation was performed; the MTD for NVP‐AUY922 plus bortezomib was not established.CONCLUSIONSThis study showed disease stabilization with NVP‐AUY922 in patients with relapsed or refractory MM. The MTD for NVP‐AUY922 was not reached, but reversible ocular toxicity has been reported at high dose levels. Bortezomib at the standard recommended dose plus NVP‐AUY922 was not tolerated. Cancer 2015;121:2185–2192. © 2015 American Cancer Society.