Randomized Trial of Five or Two MRI-guided Adaptive Radiotherapy Treatments for Prostate Cancer (FORT)

PURPOSE/OBJECTIVE(S)

The objective of this randomized clinical trial is to demonstrate that 2 treatments of real-time MRI-guided radiotherapy (RT) does not significantly increase patient-reported GI and GU symptoms compared to 5 treatments of RT 2 years after treatment completion (24 months).

MATERIALS/METHODS

Key Eligibility Criteria: Inclusion Criteria 1. Men aged > 18 with histologically confirmed low or intermediate risk prostate cancer per NCCN guidelines. 2. ECOG 0 - 1 3. IPSS < 18 4. Ability to receive MRI-guided radiotherapy. 5. Ability to complete the Expanded Prostate Cancer Index Composite (EPIC) questionnaire. Exclusion Criteria 1. Prior history of receiving pelvic RT. 2. Patient with history of IBD. 3. Hip replacements. 4. History of bladder neck or urethral stricture. 5. TURP < 8 weeks prior to RT 6. Metastatic (pelvic nodal or distant) disease on CT, Bone, and/or PSMA PET scan. Study Design/Endpoints: This is a randomized phase II non-inferiority trial comparing 2 fractions of ultrahypofractionated RT (25 Gy total with optional PSMA/MRI boost to 28 Gy) versus 5 fractions of ultra-hypofractionated RT (37.5 Gy total with optional PSMA/MRI boost to 45 Gy) in the definitive setting for prostate cancer. Subjects will be stratified based on pre-specified stratification factors and randomized 1:1 to receive 2 or 5 fractions using permuted block randomization. The primary endpoint is the change in patient-reported GI and GU symptoms as measured by EPIC at 2 years from end of treatment. Secondary endpoints will include both the safety endpoints including change in GI and GU symptoms at 3, 6, 12 and 60 months from end of treatment, and multiple efficacy endpoints including time to progression, prostate cancer specific survival and overall survival.

SAMPLE SIZE

The sample size is calculated based on a non-inferiority design. The non-inferiority margins are set to be a change score of 6 points for the GI symptoms and 5 points for the GU symptoms. The standard deviations of the change scores are assumed to be 13.2 for the GI symptoms and 10.5 for the GU symptoms based on estimates generated in RTOG 0415 trial. This level of change in scores are deemed as clinically meaningful. For example, 6 points of change score for GI symptoms corresponds to two symptoms worsening by 1 level (i.e., loose stools and frequency of bowel movements change from "no problem" to "very small problem") or one of the symptoms worsening by 2 levels (i.e., loose stool change from "no problem" to "small problem"). A sample size of 122 with 61 in each arm will ensure 80% power for GI endpoint and 83% power for GU endpoint to detect non-inferiority using a one-sided two-sample t-test at the significance level of 0.05. Adjusting for a projected 10% EPIC/non-compliance rate, 136 patients (68 per arm) will be randomized. Stratification Factors: Patients will be stratified according to baseline EPIC bowel and urinary domain scores and country of treatment. Enrollment: Twenty patients.

RESULTS

To be determined.

CONCLUSION

To be determined.

STAT3/LKB1 controls metastatic prostate cancer by regulating mTORC1/CREB pathway

Prostate cancer (PCa) is a common and fatal type of cancer in men. Metastatic PCa (mPCa) is a major factor contributing to its lethality, although the mechanisms remain poorly understood. PTEN is one of the most frequently deleted genes in mPCa. Here we show a frequent genomic co-deletion of PTEN and STAT3 in liquid biopsies of patients with mPCa. Loss of Stat3 in a Pten-null mouse prostate model leads to a reduction of LKB1/pAMPK with simultaneous activation of mTOR/CREB, resulting in metastatic disease. However, constitutive activation of Stat3 led to high LKB1/pAMPK levels and suppressed mTORC1/CREB pathway, preventing mPCa development. Metformin, one of the most widely prescribed therapeutics against type 2 diabetes, inhibits mTORC1 in liver and requires LKB1 to mediate glucose homeostasis. We find that metformin treatment of STAT3/AR-expressing PCa xenografts resulted in significantly reduced tumor growth accompanied by diminished mTORC1/CREB, AR and PSA levels. PCa xenografts with deletion of STAT3/AR nearly completely abrogated mTORC1/CREB inhibition mediated by metformin. Moreover, metformin treatment of PCa patients with high Gleason grade and type 2 diabetes resulted in undetectable mTORC1 levels and upregulated STAT3 expression. Furthermore, PCa patients with high CREB expression have worse clinical outcomes and a significantly increased risk of PCa relapse and metastatic recurrence. In summary, we have shown that STAT3 controls mPCa via LKB1/pAMPK/mTORC1/CREB signaling, which we have identified as a promising novel downstream target for the treatment of lethal mPCa.

Ketogenic diets composed of long-chain and medium-chain fatty acids induce cardiac fibrosis in mice

Heart diseases are the leading cause of deaths worldwide. Metabolic interventions via ketogenic diets (KDs) have been used for decades to treat epilepsy, and more recently, also diabetes and obesity, as common comorbidities of heart diseases. However, recent reports linked KDs, based on long-chain triglycerides (LCTs), to cardiac fibrosis and a reduction of heart function in rodents. As intervention using medium-chain triglycerides (MCTs) was recently shown to be beneficial in murine cardiac reperfusion injury, the question arises as to what extent the fatty acid (FA)-composition in a KD alters molecular markers of FA-oxidation (FAO) and modulates cardiac fibrotic outcome. Here, we show that eight weeks of feeding an LCT-KD as well as an LCT/MCT mix (8:1 ketogenic ratio) induces cardiac fibrosis in male C57/BL6NRJ mice. Despite the increased amount of collagen fibers, cardiac tissue was immunologically indistinguishable between groups. MCT supplementation resulted in i) profound changes in plasma metabolome, ii) reduced hydroxymethylglutaryl-CoA synthase upregulation, and mitofusin 2 downregulation, iii) abrogation of LCT-induced mitochondrial enlargement, and iv) enhanced FAO profile. Contrary to literature, mitochondrial biogenesis was unaffected by KDs. We propose that the tissue remodeling, which we observed, is caused by the accumulation of 4-hydroxy-2-nonenal protein adducts, despite an inconspicuous nuclear factor (erythroid-derived 2)-like 2 pathway. We conclude that in spite of the generally favorable effects of MCTs, they cannot inhibit 4-hydroxy-2-nonenal adduct formation and fibrotic tissue formation in this setting. Furthermore, we support the burgeoning concern about the effect of KDs on the cardiac safety profile.

KMT2C methyltransferase domain regulated INK4A expression suppresses prostate cancer metastasis

BACKGROUND

Frequent truncation mutations of the histone lysine N-methyltransferase KMT2C have been detected by whole exome sequencing studies in various cancers, including malignancies of the prostate. However, the biological consequences of these alterations in prostate cancer have not yet been elucidated.

METHODS

To investigate the functional effects of these mutations, we deleted the C-terminal catalytic core motif of Kmt2c specifically in mouse prostate epithelium. We analysed the effect of Kmt2c SET domain deletion in a Pten-deficient PCa mouse model in vivo and of truncation mutations of KMT2C in a large number of prostate cancer patients.

RESULTS

We show here for the first time that impaired KMT2C methyltransferase activity drives proliferation and PIN formation and, when combined with loss of the tumour suppressor PTEN, triggers loss of senescence, metastatic dissemination and dramatically reduces life expectancy. In Kmt2c-mutated tumours we show enrichment of proliferative MYC gene signatures and loss of expression of the cell cycle repressor p16^INK4A. In addition, we observe a striking reduction in disease-free survival of patients with KMT2C-mutated prostate cancer.

CONCLUSIONS

We identified truncating events of KMT2C as drivers of proliferation and PIN formation. Loss of PTEN and KMT2C in prostate cancer results in loss of senescence, metastatic dissemination and reduced life expectancy. Our data demonstrate the prognostic significance of KMT2C mutation status in prostate cancer patients. Inhibition of the MYC signalling axis may be a viable treatment option for patients with KMT2C truncations and therefore poor prognosis.

Correction: Dependency on the TYK2/STAT1/MCL1 axis in anaplastic large cell lymphoma

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Dependency on the TYK2/STAT1/MCL1 axis in anaplastic large cell lymphoma

TYK2 is a member of the JAK family of tyrosine kinases that is involved in chromosomal translocation-induced fusion proteins found in anaplastic large cell lymphomas (ALCL) that lack rearrangements activating the anaplastic lymphoma kinase (ALK). Here we demonstrate that TYK2 is highly expressed in all cases of human ALCL, and that in a mouse model of NPM-ALK-induced lymphoma, genetic disruption of Tyk2 delays the onset of tumors and prolongs survival of the mice. Lymphomas in this model lacking Tyk2 have reduced STAT1 and STAT3 phosphorylation and reduced expression of Mcl1, a pro-survival member of the BCL2 family. These findings in mice are mirrored in human ALCL cell lines, in which TYK2 is activated by autocrine production of IL-10 and IL-22 and by interaction with specific receptors expressed by the cells. Activated TYK2 leads to STAT1 and STAT3 phosphorylation, activated expression of MCL1 and aberrant ALCL cell survival. Moreover, TYK2 inhibitors are able to induce apoptosis in ALCL cells, regardless of the presence or absence of an ALK-fusion. Thus, TYK2 is a dependency that is required for ALCL cell survival through activation of MCL1 expression. TYK2 represents an attractive drug target due to its essential enzymatic domain, and TYK2-specific inhibitors show promise as novel targeted inhibitors for ALCL.

Abstract P6-08-01: Not presented

This abstract was not presented at the conference.

Citation Format: Guimarães I, Gimba E, Castelo-Branco M, Sternberg C, Silva I, Rangel L. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-08-01.

Synergistic cross-talk of hedgehog and interleukin-6 signaling drives growth of basal cell carcinoma

Persistent activation of hedgehog (HH)/GLI signaling accounts for the development of basal cell carcinoma (BCC), a very frequent nonmelanoma skin cancer with rising incidence. Targeting HH/GLI signaling by approved pathway inhibitors can provide significant therapeutic benefit to BCC patients. However, limited response rates, development of drug resistance, and severe side effects of HH pathway inhibitors call for improved treatment strategies such as rational combination therapies simultaneously inhibiting HH/GLI and cooperative signals promoting the oncogenic activity of HH/GLI. In this study, we identified the interleukin‐6 (IL6) pathway as a novel synergistic signal promoting oncogenic HH/GLI via STAT3 activation. Mechanistically, we provide evidence that signal integration of IL6 and HH/GLI occurs at the level of cis‐regulatory sequences by co‐binding of GLI and STAT3 to common HH‐IL6 target gene promoters. Genetic inactivation of Il6 signaling in a mouse model of BCC significantly reduced in vivo tumor growth by interfering with HH/GLI‐driven BCC proliferation. Our genetic and pharmacologic data suggest that combinatorial HH‐IL6 pathway blockade is a promising approach to efficiently arrest cancer growth in BCC patients.

What's new?

Persistent activation of hedgehog (HH)/GLI signaling represents the main driver signal for the development of basal cell carcinoma (BCC), a common non‐melanoma skin cancer with rising incidence. Small molecule hedgehog pathway inhibitors are successfully used for the treatment of hedgehog‐driven BCC, but frequent drug resistance calls for improved strategies. Here, the authors identified the interleukin‐6 pathway as a novel synergistic signal promoting oncogenic HH/GLI via STAT3 activation. The synergistic interaction was required for the in vivo growth of hedgehog‐driven BCC. The study thus provides a rationale for effective combination treatments simultaneously targeting oncogenic hedgehog and interleukin‐6 signaling in BCC patients.

Behçet Syndrome Associated with Protein S Deficiency

Beçget syndrome is a multisystem disorder characterized by ocular, mucocutaneous, articular, gastrointestinal and neurologic abnormalities. We report here an unusual case of Beçget syndrome, characterized by the importance of the thrombotic events(7 phlebitis of both legs and resection of two toes). Additional manifestations of the Beçget syndrome occurred only 10 years after the first thrombotic episode. The oldest daugther of the propositus and his brother suffered also from thrombophlebitis; this familial history of thrombosis led to the performance of a haemostatic study. A congenital protein S deficiency was found in the propositus and in three of his children. Normal protein S levels were found in nine unrelated patients with Beçget syndrome. Thus this observation suggests that, when thrombotic manifestations are the first and major symptom of Beçget syndrom, an additional cause of thrombosis has to be investigated.

Antithrombin III Alger: A New Homozygous AT III Variant

A qualitative abnormality of antithrombin III (AT III) was found in the plasma of a 41-year old patient. The plasmatic AT III antigen concentration was 130% and the progressive anti-F IIa and anti-F Xa activities were normal (105% and 137%). The plasma heparin cofactor activity was less than 10%, when measured by F Ila or F Xa inhibition. Crossed immunoelectrophoresis of AT III in the presence of heparin revealed in the plasma an abnormal slow-moving peak. When tested by affinity chromatography on heparin Sepharose, this abnormal AT III did not bind to heparin. Among the investigated relatives, 5 subjects had normal AT III levels, whatever the test used, the nine others having reduced levels of antithrombin heparin cofactor activity (45-61%) but normal levels of immunoreactive AT III (97-122%). Consanguinity was found in the family history. We therefore considered our patient as homozygous for an AT III molecular abnormality affecting the binding site for heparin.

The use of biosimilar medicines in oncology - position statement of the Brazilian Society of Clinical Oncology (SBOC)

A biosimilar is a biologic product that is similar to a reference biopharmaceutical product, the manufacturing process of which hinders the ability to identically replicate the structure of the original product, and therefore, it cannot be described as an absolute equivalent of the original medication. The currently available technology does not allow for an accurate copy of complex molecules, but it does allow the replication of similar molecules with the same activity. As biosimilars are about to be introduced in oncology practice, these must be evaluated through evidence-based medicine. This manuscript is a position paper, where the Brazilian Society of Clinical Oncology (SBOC) aims to describe pertinent issues regarding the approval and use of biosimilars in oncology. As a working group on behalf of SBOC, we discuss aspects related to definition, labeling/nomenclature, extrapolation, interchangeability, switching, automatic substitution, clinical standards on safety and efficacy, and the potential impact on financial burden in healthcare. We take a stand in favor of the introduction of biosimilars, as they offer a viable, safe, and cost-effective alternative to the biopharmaceutical products currently used in cancer. We hope this document can provide valuable information to support therapeutic decisions that maximize the clinical benefit for the thousands of cancer patients in Brazil and can contribute to expedite the introduction of this new drug class in clinical practice. We expect the conveyed information to serve as a basis for further discussion in Latin America, this being the first position paper issued by a Latin American Oncology Society.

Antithrombotic and Anticoagulant Activities of a Low Molecular Weight Fucoidan by the Subcutaneous Route

Fucoidans (high-molecular-weight sulfated polysaccharides extracted from brown seaweeds) have anticoagulant and antithrombotic effects. They inhibit thrombin by catalyzing both serpins (antithrombin and heparin cofactor II) according to their chemical structures and origins. In this study, a low-molecular-weight (LMW) fucoidan of 8 kDa was obtained by chemical degradation of a high-molecular-weight fraction. The antithrombotic and anticoagulant activities of this new compound were compared to those of a low-molecular-weight heparin (LMWH), dalteparin, following subcutaneous administration to rabbits. This LMW fucoidan exhibited dose-related venous antithrombotic activity, with an ED80 of about 20 mg/kg, 2 h after a single subcutaneous injection. Its activity was comparable to that of dalteparin (close to 200 anti-Xa IU/kg) and was maximal 30 min after a single subcutaneous injection. The activity remained stable (about 70%) from 1 to 4 h after injection, but disappeared by 8 h. The antithrombotic activity was not associated with either a prolongation of the thrombin clotting time (TCT) or an increase in anti-Xa activity, contrary to dalteparin. A slight prolongation of APTT occurred with both compounds. This venous antithrombotic activity was associated with a decrease in ex vivo thrombin generation and with a significant increase in the lag phase in a thrombin generation test. LMW fucoidan thus has potent antithrombotic activity and a potentially weaker haemorrhagic effect (i.e. a smaller effect on coagulation tests and a smaller prolongation of the bleeding time) than dalteparin.

Radiotherapy modulates expression of EGFR, ERCC1 and p53 in cervical cancer

Cervical cancer is a public health problem and the molecular mechanisms underlying radioresistance are still poorly understood. Here, we evaluated the modulation of key molecules involved in cell proliferation, cell cycle and DNA repair in cervical cancer cell lines (CASKI and C33A) and in malignant tissues biopsied from 10 patients before and after radiotherapy. The expression patterns of epidermal growth factor receptor (EGFR), excision repair cross-complementation group 1 (ERCC1) and p53 were evaluated in cancer cell lines by quantitative PCR and western blotting, and in human malignant tissues by immunohistochemistry. The mutation status of TP53 gene was evaluated by direct sequencing. Among cell lines, absent or weak modulations of EGFR, ERCC1 and p53 were observed after exposure to 1.8 Gy. Conversely, increased expressions of p53 (5/10 patients; P=0.0239), ERCC1 (5/10 patients; P=0.0294) and EGFR (4/10 patients; P=0.1773) were observed in malignant tissues after radiotherapy with the same radiation dose. TP53 mutations were found only in one patient. Here we show that a single dose of radiotherapy induced EGFR, ERCC1 and p53 expression in malignant tissues from cervical cancer patients but not in cancer cell lines, highlighting the gap between in vitro and in vivo experimental models. Studies on larger patient cohorts are needed to allow an interpretation that an upregulation of p53, EGFR and ERCC1 may be part of a radioresistance mechanism.

Targeting class I histone deacetylases by the novel small molecule inhibitor 4SC-202 blocks oncogenic hedgehog-GLI signaling and overcomes smoothened inhibitor resistance

Aberrant activation of Hedgehog (HH)/GLI signaling is causally involved in numerous human malignancies, including basal cell carcinoma (BCC) and medulloblastoma. HH pathway antagonists targeting smoothened (SMO), an essential effector of canonical HH/GLI signaling, show significant clinical success in BCC patients and have recently been approved for the treatment of advanced and metastatic BCC. However, rapid and frequent development of drug resistance to SMO inhibitors (SMOi) together with severe side effects caused by prolonged SMOi treatment call for alternative treatment strategies targeting HH/GLI signaling downstream of SMO. In this study, we report that 4SC-202, a novel clinically validated inhibitor of class I histone deacetylases (HDACs), efficiently blocks HH/GLI signaling. Notably, 4SC-202 treatment abrogates GLI activation and HH target gene expression in both SMOi-sensitive and -resistant cells. Mechanistically, we propose that the inhibition of HDACs 1/2/3 is crucial for targeting oncogenic HH/GLI signaling, and that class I HDAC inhibitors either in combination with SMOi or as second-line therapy may improve the treatment options for HH-associated malignancies with SMOi resistance.

Acute myeloid leukemia - strategies and challenges for targeting oncogenic Hedgehog/GLI signaling

Treatment of acute myeloid leukemia (AML), an aggressive and heterogeneous hematological malignancy, remains a challenge. Despite advances in our understanding of the complex genetics and biology of AML pathophysiology, these findings have been translated to the clinic with only limited success, and poor outcomes persist for the majority of patients. Thus, novel treatment strategies are clearly needed for achieving deeper and prolonged remissions and for avoiding the development of resistance. Due to its profound role in (cancer) stem cell biology and differentiation, the Hedgehog (HH)/Glioma-associated Oncogene Homolog (GLI) signaling pathway may be an attractive novel therapeutic target in AML. In this review, we aim to provide a critical and concise overview of the currently known potential and challenges of HH/GLI targeting. We describe the biological role of the HH/GLI pathway in AML pathophysiology. We specifically focus on ways of targeting non-canonical HH/GLI signaling in AML, particularly in combination with standard treatment regimens, which may overcome some hurdles observed with approved HH pathway inhibitors in solid tumors.

[Patch Augmentation in Rotator Cuff Repair Surgery with Elder Patients]

Background: Massive rotator cuff tendon tears have a poor clinical prognosis. This holds especially true in older patients and after revision surgery. In order to reduce tears and increase long term shoulder parameters, patches made of a variety of materials have been applied to reinforce sutures in current orthopaedic practice. Material and Methods: In a clinical study on rotator cuff surgery from 2005 to 2011 (date of surgical intervention), we tested the efficacy of three different commercial patches, with 89 patients (63 m/26 w) enrolled with a mean age of over 60. Graft Jacket, a regenerative stable human tissue scaffold, Artelon, a slow-resorbable polyurethane-urea patch and Restore, an orthobiological degradable graft, were arthroscopically implanted in order to augment the fragile tendon-bone interface after massive tears of 2 to 3 tendons (supraspinatus and/or infraspinatus and/or subscapularis). Results: An overall repair integrity score of 75 % was achieved in primary rotator cuff surgery and of 65 % in revision surgery with either non- or slowly resorbable patches outperforming the degradable material. This effect is more marked after primary surgery. CS values indicate overall patient recovery at 6 months of 81.43 vs. 47.29 for Graft Jacket, 81.34 vs. 46.18 for Artelon and 78.45 vs. 41.93 for Restore. Subjective shoulder value (SSV) at 3 years increased to 9.11 vs. 4.32 for Graft Jacket, 9.31 vs. 3.53 for Artelon and 9.45 vs. 2.9 for Restore. No severe adverse affects were encountered. Conclusions: Tendons with reduced mechanical characteristics can greatly profit from patch augmentation. This holds especially true for older patients and in revision surgery. The success rate of our patch studies was up to 87 % for Graft Jacket in primary rotator cuff surgery and a minimum of 58.3 % for Restore in pure revision surgery (comparable studies/metastudies on massive rotator cuff tear repair success rates range from 43 to 59 %). This paves the way for a continued search for better and more intelligent materials. Yield load, stiffness and ultimate load will probably improve further in the very near future.

DYRK1B as therapeutic target in Hedgehog/GLI-dependent cancer cells with Smoothened inhibitor resistance

A wide range of human malignancies displays aberrant activation of Hedgehog (HH)/GLI signaling, including cancers of the skin, brain, gastrointestinal tract and hematopoietic system. Targeting oncogenic HH/GLI signaling with small molecule inhibitors of the essential pathway effector Smoothened (SMO) has shown remarkable therapeutic effects in patients with advanced and metastatic basal cell carcinoma. However, acquired and de novo resistance to SMO inhibitors poses severe limitations to the use of SMO antagonists and urgently calls for the identification of novel targets and compounds.Here we report on the identification of the Dual-Specificity-Tyrosine-Phosphorylation-Regulated Kinase 1B (DYRK1B) as critical positive regulator of HH/GLI signaling downstream of SMO. Genetic and chemical inhibition of DYRK1B in human and mouse cancer cells resulted in marked repression of HH signaling and GLI1 expression, respectively. Importantly, DYRK1B inhibition profoundly impaired GLI1 expression in both SMO-inhibitor sensitive and resistant settings. We further introduce a novel small molecule DYRK1B inhibitor, DYRKi, with suitable pharmacologic properties to impair SMO-dependent and SMO-independent oncogenic GLI activity. The results support the use of DYRK1B antagonists for the treatment of HH/GLI-associated cancers where SMO inhibitors fail to demonstrate therapeutic efficacy.

ILK Induction in Lymphoid Organs by a TNFα-NF-κB-Regulated Pathway Promotes the Development of Chronic Lymphocytic Leukemia

The proliferation of chronic lymphocytic leukemia (CLL) cells requires communication with the lymphoid organ microenvironment. Integrin-linked kinase (ILK) is a multifunctional intracellular adaptor protein that transmits extracellular signals to regulate malignant cell motility, metastasis, and cell-cycle progression, but is poorly characterized in hematologic malignancies. In this study, we investigated the role of ILK in the context of CLL and observed high ILK expression in patient samples, particularly in tumor cells harboring prognostic high-risk markers such as unmutated IGHV genes, high Zap70, or CD38 expression, or a signature of recent proliferation. We also found increased numbers of Ki67 (MKI67)-positive cells in regions of enhanced ILK expression in lymph nodes from CLL patients. Using coculture conditions mimicking the proliferative lymph node microenvironment, we detected a parallel induction of ILK and cyclin D1 (CCND1) expression in CLL cells that was dependent on the activation of NF-κB signaling by soluble TNFα. The newly synthesized ILK protein colocalized to centrosomal structures and was required for correct centrosome clustering and mitotic spindle organization. Furthermore, we established a mouse model of CLL in which B-cell-specific genetic ablation of ILK resulted in decelerated leukemia development due to reduced organ infiltration and proliferation of CLL cells. Collectively, our findings describe a TNFα-NF-κB-mediated mechanism by which ILK expression is induced in the lymph node microenvironment and propose that ILK promotes leukemogenesis by enabling CLL cells to cope with centrosomal defects acquired during malignant transformation. Cancer Res; 76(8); 2186-96. ©2016 AACR.

Modular microfluidic system as a model of cystic fibrosis airways

A modular microfluidic airways model system that can simulate the changes in oxygen tension in different compartments of the cystic fibrosis (CF) airways was designed, developed, and tested. The fully reconfigurable system composed of modules with different functionalities: multichannel peristaltic pumps, bubble traps, gas exchange chip, and cell culture chambers. We have successfully applied this system for studying the antibiotic therapy of Pseudomonas aeruginosa, the bacteria mainly responsible for morbidity and mortality in cystic fibrosis, in different oxygen environments. Furthermore, we have mimicked the bacterial reinoculation of the aerobic compartments (lower respiratory tract) from the anaerobic compartments (cystic fibrosis sinuses) following an antibiotic treatment. This effect is hypothesised as the one on the main reasons for recurrent lung infections in cystic fibrosis patients.

Caspase dependence of the death of neonatal retinal ganglion cells induced by axon damage and induction of autophagy as a survival mechanism

We examined the degeneration of post-mitotic ganglion cells in ex-vivo neonatal retinal explants following axon damage. Ultrastructural features of both apoptosis and autophagy were detected. Degenerating cells reacted with antibodies specific for activated caspase-3 or -9, consistent with the presence of caspase activity. Furthermore, peptidic inhibitors of caspase-9, -6 or -3 prevented cell death (100 µM Ac-LEDH-CHO, 50 µM Ac-VEID-CHO and 10 µM Z-DEVD-fmk, respectively). Interestingly, inhibition of autophagy by 7-10 mM 3-methyl-adenine increased the rate of cell death. Immunohistochemistry data, caspase activation and caspase inhibition data suggest that axotomy of neonatal retinal ganglion cells triggers the intrinsic apoptotic pathway, which, in turn, is counteracted by a pro-survival autophagic response, demonstrated by electron microscopy profiles and pharmacological autophagy inhibitor.

A phase II study of once-daily dasatinib for patients with castration-resistant prostate cancer (CRPC) (CA180085)

5147

Background: Dasatinib is a potent oral SRC family kinase inhibitor that also inhibits c-KIT and PDGFR in vitro. The anti-proliferative/anti-metastatic activity as well as osteoclast inhibitory function of dasatinib in pre-clinical models supports its potential as a targeted therapy for prostate cancer. Previously we presented results on BID dosing of dasatinib in the treatment of CRPC (ASCO. 2008 Abstract 5156). A second group of patients (pts) was enrolled to investigate the activity, safety and bone effects of 100 mg once daily dosing. Methods: Male pts with progressive metastatic CRPC, rising PSA, castrate levels of testosterone (< 50 ng/dL) and no prior chemotherapy were enrolled. Dasatinib dose was 100 mg QD. Continuation of bisphosphonates was permitted. Primary endpoint was a composite of: PSA responses, bone scans and disease control by RECIST. Urinary N-telopeptide (uNTX) and bone alkaline phosphatase (BAP) were determined Q 4-weeks as indicators of bone metabolism. Results: 47 pts were treated (median treatment duration was 2.3 months). 11 patients were evaluable by RECIST; of these 64% achieved SD. The composite response rate was (8/47) 17%. Of 22 pts with bone scans, 50% were stable at 12 weeks and 3/9 (33%) were stable at 24 weeks. A prolonged PSA doubling time was observed in 32 of 39 pts (82%), including one pt with a PSA response. Of the pts with evaluable bone markers, including those who continued on bisphosphonate therapy, 20/41 (49%) had a ≥ 35% decrease in uNTX and 21/42 (50%) had a decrease from baseline in BAP. Grade 3/4 adverse events (AEs) were experienced by 13% of pts (diarrhea, asthenia, and pleural effusion [n=1]). Grade 1/2 AEs (≥ 15% of pts) were diarrhea, nausea, headache, fatigue, asthenia, anorexia and dyspnea. Conclusions: Fewer and less severe AEs were observed in all categories for the QD dosing group compared to the previously reported BID dosing cohort. In addition, preliminary clinical activity (tumor and PSA response; decreasing bone turnover [uNTX, BAP]), is now confirmed to be similar in pts treated with 100mg QD and BID dosing. These data support the relevance of further studies of dasatinib in metastatic CRPC.

[Table: see text]

An open-label extension study to evaluate safety and efficacy of pazopanib in patients with advanced renal cell carcinoma (RCC)

5110

Background: The efficacy and safety of pazopanib (paz), a multikinase angiogenesis inhibitor, was evaluated in a randomized, double-blind placebo-controlled phase III study (VEG105192), in treatment-naïve and cytokine-pretreated patients (pts) with advanced RCC. Pts with progressive disease (PD) on placebo had the option to receive paz 800 mg QD via an extension study (VEG107769). Methods: Pts with ECOG PS ≤ 2, adequate organ function and no other systemic anticancer treatment since PD on VEG105192 were eligible. The primary endpoint was safety. Secondary endpoints included response rate (RR) per RECIST and progression-free survival (PFS). RR was described along with 95% confidence intervals (CIs). PFS was summarized descriptively using Kaplan-Meier estimates for the median, quartiles and PFS rates at 6, 12, and 18 mo along with approximate 95% CIs. Results: 70 placebo pts were enrolled (+ 1 paz pt as an exemption due to symptom improvement). 34 pts (48%) were treatment-naïve and 37 (52%) were cytokine pretreated (at baseline in VEG105192). Median age was 59 y (25–80); baseline ECOG PS 0 (32%), 1 (52%), and 2 (14%). Median time from randomization to placebo in VEG105192 to start of paz treatment on VEG107769 was 6.4 mo (1–18 mo). At VEG107769 clinical cut-off (May 08), 21 (30%) pts had died, 40 (56%) pts had discontinued paz, and 31 (44%) pts were still on paz. Median exposure to paz was 5.7 mo. Most pts died or discontinued paz due to PD. The majority of adverse events (AEs) were Gr 1/2. Gr 3/4 AEs were experienced by 21%/7% of pts. The most common AEs were hypertension (46%; 4% Gr 3/4), hair color changes (39%; 0% Gr 3/4), diarrhea (38%; 1% Gr 3/4), anorexia (24%; 1% Gr 3/4), and nausea (24%; 0% Gr 3/4). Two pts had fatal AEs: sudden death and gastrointestinal hemorrhage. The most common Gr 3 chemistry laboratory abnormalities were hyponatremia (7%) and elevated ALT (7%) and AST (6%); no Gr 4. RR was 32.4% (95% CI: 21.5, 43.3); median PFS was 8.3 mo (95% CI: 6.1, 11.4 mo). Conclusions: Patients with advanced RCC who developed PD on placebo in a phase III study subsequently achieved clinical benefit from paz treatment in this extension study. These findings support the continued evaluation of paz in advanced RCC.

[Table: see text]

Dose finding study of the combination of satraplatin and gemcitabine in patients with advanced solid tumors

e13534

Background: The potential advantage of combining satraplatin (S) a novel oral platinum with Gem is attractive. MTD and DLT of combination S and Gem in patients (pts) with advanced solid tumors was evaluated. Methods: Cohorts of 3–6 pts (modified Fibonacci) received escalating doses of i.v. Gem on days (d) 1, 8 and 15 Q 28 d followed by oral S on d 1–5. Seventeen pts with metastatic solid tumors were separated into 2 groups: A) Pts that had progressed following cytotoxic therapy and B) Pts who had received no prior chemotherapy. Starting dose was Gem 800 mg in both groups, S 40 mg and 60 mg for A and B respectively. Results: Group A. 6 previously treated pts with 1 or 2 regimens (3 prostate, 1 hepatocarcinoma, 1 bladder and 1 thymic ca) received 25 cycles, median 2 (2–12). 2 DLTs (G3 transaminases) were observed in 6 pts treated at level 1. Other G3 major toxicities were: thrombocytopenia (1 pt) and diarrhea (1 pt). 2 pts had PSA declines, with TTP of 630 days in 1 of them. Group B. 11 pts with no prior chemotherapy (4 hepatocarcinoma, 4 pancreas, 1 renal, 1 unknown origin and 1 gallbladder), received 38 cycles, median 2 (1–12). 1 DLT (G3 diarrhea) was observed in 8 pts treated at level 1 (2 not evaluable; received Gem d1 only), DLT (G3 thrombocytopenia) was observed in 3 pts treated at level 2 (Gem 1000, S 60). Other G3 toxicities were: thrombocytopenia (3 pts) and neutropenia (3 pts). 1 CR (pancreas) and 1 PR (gallbladder) were observed. Gem d8 or d15 was omitted in 11 of 17 pts during the 1st cycle. Conclusions: In this study the combination of S and Gem showed a clinically acceptable toxicity profile with promising antitumor activity. However, since in cycle 1, it was not possible to administer Gem on both d8 and d15 on 11 occasions, a 2nd study was initiated with S d1–3 and Gem d1 and 8 given on a Q 21 d schedule. Sponsored by GPC Biotech

No significant financial relationships to disclose.

Use of pain at baseline and pain progression to predict overall survival (OS) in patients (pts) with docetaxel pretreated metastatic castration-refractory prostate cancer (CRPC): Results from the SPARC trial

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Background: First-line chemotherapy trials have reported that pain predicts OS in CRPC. We report relationships between OS and baseline pain –a major component of CRPC patient reported outcomes (PRO) –and pain at progression, for docetaxel pre-treated patients in a second-line chemotherapy trial in CRPC. Methods: Docetaxel pre-treated pts (N = 488) were analyzed from the multi-national, randomized, double-blind SPARC trial, comparing second-line satraplatin + prednisone vs placebo + prednisone in 950 metastatic CRPC pts. Daily pain intensity and narcotic analgesic use were recorded as a PRO from one week prior to randomization until end-of-study. Pain was measured by the 6-point Present Pain Intensity (PPI) component of the McGill-Melzack Pain Questionnaire. After randomization, weekly PPI scores were calculated as the mean of the daily PPI scores (using ≥3 daily measurements/week). Baseline pain was the mean of ≥5 daily PPI scores recorded during 7 days preceding randomization. An independent blinded review committee (IRC) determined pain progression (defined as an increase in weekly PPI score ≥1 point from baseline or ≥2 points from nadir, or a >25% increase from baseline in weekly average analgesic score for ≥2 consecutive weeks). To examine the effects of pain on OS, pts were categorized as “no pain” (PPI ≤1) or pain (PPI ≥2) by baseline assessment; and, as either pain progressors or pain non-progressors. Results: Shortened OS was observed in pts with baseline pain; median survival of 178 pts with pain was 44 weeks vs 72 weeks for 287 pts without pain (Strat. Log-rank p < 0.0001, Strat. HR 0.59; 95% CI: 0.48–0.74). IRC found disease progression in 414 (84.4%) of the docetaxel pre-treated pts with 196 of these pts showing pain progression. Pain progression was strongly linked to OS with 196 pain progressors having median OS of 47 weeks compared to 71 weeks for 292 pain non-progressors (Strat. Log-Rank p = 0.0022; Strat. HR 0.71; 95% CI: 0.57–0.87). Conclusions: Both pain at baseline and pain at progression are important prognostic indicators of OS in metastatic CRPC pts failing first-line docetaxel.

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