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In eukaryotic cells, biological activities are executed in distinct cellular compartments or organelles. Canonical organelles with membrane‐bound structures are well understood. Cells also inherently contain versatile membrane‐less organelles (MLOs) that feature liquid or gel‐like bodies. A biophysical process termed liquid–liquid phase separation (LLPS) elucidates how MLOs form through dynamic biomolecule assembly. LLPS‐related molecules often have multivalency, which is essential for low‐affinity inter‐ or intra‐molecule interactions to trigger phase separation. Accumulating evidence shows that LLPS concentrates and organizes desired molecules or segregates unneeded molecules in cells. Thus, MLOs have tunable functional specificity in response to environmental stimuli and metabolic processes. Aberrant LLPS is widely associated with several hallmarks of cancer, including sustained proliferative signaling, growth suppressor evasion, cell death resistance, telomere maintenance, DNA damage repair, etc. Insights into the molecular mechanisms of LLPS provide new insights into cancer therapeutics. Here, the current understanding of the emerging concepts of LLPS and its involvement in cancer are comprehensively reviewed. [ABSTRACT FROM AUTHOR]

Objective To evaluate the adverse effects and therapeutic efficacy of our biocompatible polymer platform delivering targeted local therapy of cytokine CCL21 and cisplatin in a partially resected xenograft animal model of head and neck squamous cell carcinoma. In addition, to evaluate the efficacy of cotreatment with radiotherapy and assess the biocompatibility of the cisplatin-eluting polymer in the murine neck. Study Design Experimental animal study. Setting Academic research laboratory. Subjects and Methods SCCVII/SF cell injection established head and neck squamous cell carcinoma tumors in C3H/HeJ mice. Subjects underwent surgery, and a chemokine-eluting polymer was implanted into the resected site. Subjects treated with cisplatin received radiation or no radiation, and tissue was harvested after 8 weeks to assess polymer biocompatibility. Results Our results with the polymer platform significantly ( P < .05) reduced SCCVII/SF tumor size in C3H/HeJ mice with cisplatin (49% ± 8.7%, Δ3.4 ± 0.6 cm3 [95% CI]), CCL21 (42% ± 4.8%, Δ3.5 ± 0.4 cm3), and cisplatin/CCL21 dual-agent polymer (82% ± 4.4%, Δ8.0 ± 0.4 cm3) as compared with controls. Cisplatin polymer with high-dose (16 Gy) and low-dose (4 Gy) radiation reduced tumor mass (respectively, 92% ± 7.2%, Δ6.1 ± 0.5 cm3; 85% ± 7.4%, Δ5.7 ± 0.5 cm3) as compared with the reduction from high-dose radiotherapy alone (70% ± 7.9%, Δ4.7 ± 0.5 cm3). No significant toxicity or inflammation was noted on histopathology after radiotherapy and cisplatin-eluting polymer treatment. Conclusion Cisplatin, CCL21, and cisplatin/CCL21 dual-agent polymer all exhibit significant antitumor effects and decrease tumor burden. Moreover, combination cisplatin polymer with radiotherapy may permit a decrease in intensity of radiation therapy in patients having received the cisplatin polymer. Histopathologic analysis suggests that the polymer is free from significant adverse effects in this model and warrants clinical trial. [ABSTRACT FROM AUTHOR]

Development of effective treatments for alcohol use disorder (AUD) represents an important public health goal. This review provides a summary of completed preclinical and clinical studies testing pharmacotherapies for the treatment of AUD. We discuss opportunities for improving the translation from preclinical findings to clinical trial outcomes, focusing on the validity and predictive value of animal and human laboratory models of AUD. Specifically, while preclinical studies of medications development have offered important insights into the neurobiology of the disorder and alcohol's molecular targets, limitations include the lack of standardized methods and streamlined processes whereby animal studies can readily inform human studies. Behavioral pharmacology studies provide a less expensive and valuable opportunity to assess the feasibility of a pharmacotherapy prior to initiating larger scale clinical trials by providing insights into the mechanism of the drug, which can then inform recruitment, analyses, and assessments. Summary tables are provided to illustrate the wide range of preclinical, human laboratory, and clinical studies of medications development for alcoholism. Taken together, this review highlights the challenges associated with animal paradigms, human laboratory studies, and clinical trials with the overarching goal of advancing treatment development and highlighting opportunities to bridge the gap between preclinical and clinical research. [ABSTRACT FROM AUTHOR]

Our prior study utilized both in vitro and in vivo multiple myeloma ( MM) xenograft models to show that a novel alkylator melphalan-flufenamide (Melflufen) is a more potent anti- MM agent than melphalan and overcomes conventional drug resistance. Here we examined whether this potent anti- MM activity of melflufen versus melphalan is due to their differential effect on DNA damage and repair signalling pathways via γ-H2 AX/ ATR/ CHK1/Ku80. Melflufen-induced apoptosis was associated with dose- and time-dependent rapid phosphorylation of γ-H2 AX. Melflufen induces γ-H2 AX, ATR, and CHK1 as early as after 2 h exposure in both melphalan-sensitive and -resistant cells. However, melphalan induces γ-H2 AX in melphalan-sensitive cells at 6 h and 24 h; no γ-H2 AX induction was observed in melphalan-resistant cells even after 24 h exposure. Similar kinetics was observed for ATR and CHK1 in meflufen- versus melphalan-treated cells. DNA repair is linked to melphalan-resistance; and importantly, we found that melphalan, but not melflufen, upregulates Ku80 that repairs DNA double-strand breaks. Washout experiments showed that a brief (2 h) exposure of MM cells to melflufen is sufficient to initiate an irreversible DNA damage and cytotoxicity. Our data therefore suggest that melflufen triggers a rapid, robust, and an irreversible DNA damage which may account for its ability to overcome melphalan-resistance in MM cells. [ABSTRACT FROM AUTHOR]

Background There have been significant advances in understanding the pathophysiological mechanisms in patients with neurogastroenterological disorders including irritable bowel syndrome ( IBS) and functional abdominal pain, functional diarrhea, chronic constipation, gastroparesis, and functional dyspepsia. These advances have led to the development of novel pharmacological therapy of neurogastroenterological disorders. Purpose To review peer-reviewed articles or prominent preliminary communications presented in the past year regarding medications in development for functional gastrointestinal disorders or gastroparesis. The medications fall into two main categories: first, established classes of medications within established classes, such as 5- HT3 receptor antagonists and 5- HT4 receptor agonists, and second, new classes of medications such as a combined μ-opioid agonist and δ-antagonist, or a small molecule ghrelin agonist. [ABSTRACT FROM AUTHOR]

BACKGROUND: The authors report a retrospective analysis of high-dose ifosfamide, carboplatin, and etoposide (HD-ICE) for patients with refractory or relapsed neuroblastoma (NB). A major reason for using this regimen was the long time since patients received previous treatment with a platinum compound. The authors also summarized the published experience on ICE in patients with NB. METHODS: Treatment comprised ifosfamide (2000 mg/m2 daily for 5 days), carboplatin (500 mg/m2 daily for 2 days), and etoposide (100 mg/m2 daily for 5 days). Patients who had poor hematologic reserve (platelet count <100,000/μL) from previous therapy received peripheral blood stem cells (PBSCs) after HD-ICE. Disease status before and after HD-ICE was defined according to International Neuroblastoma Response Criteria (expanded to include 123I-metaiodobenzylguanidine findings). Publications that were informative about ICE for NB were reviewed. RESULTS: Seventy-four patients received 92 cycles of ICE, including 37 patients who received PBSC rescue. Grade 3 toxicities were rare: 1-3 patients had encephalopathy, mucositis, or gastroenteritis. Bacteremia was documented in 24 of 92 cycles (26%). The absolute neutrophil count reached 500/μL on day 17-30 (median, day 22) in patients who had satisfactory hematologic reserve. Disease regressions (major and minor responses) were achieved by 14 of 17 patients (82%) with a new relapse, 13 of 26 patients (50%) with refractory NB, and 12 of 34 patients (35%) who were treated for progressive disease during chemotherapy ( P = .005). In the literature, patients received ICE at lower dosages and achieved major response rates >36% in phase 1 and 2 studies (in which less comprehensive staging evaluations were used) that involved resistant NB and >70% in induction for newly diagnosed NB. CONCLUSIONS: HD-ICE is appealing as salvage treatment or consolidative therapy because of its anti-NB activity and the low risk of major nonhematologic toxicity. PBSC support is unnecessary for patients who had intact hematologic reserve. Cancer 2013. © 2012 American Cancer Society. [ABSTRACT FROM AUTHOR]

Abstract: The cancer stem cell (CSC) hypothesis postulates that tumors are maintained by a self-renewing CSC population that is also capable of differentiating into non-self-renewing cell populations that constitute the bulk of the tumor. Although, the CSC hypothesis does not directly address the cell of origin of cancer, it is postulated that tissue-resident stem or progenitor cells are the most common targets of transformation. Clinically, CSCs are predicted to mediate tumor recurrence after chemo- and radiation-therapy due to the relative inability of these modalities to effectively target CSCs. If this is the case, then CSC must be efficiently targeted to achieve a true cure. Similarities between normal and malignant stem cells, at the levels of cell-surface proteins, molecular pathways, cell cycle quiescence, and microRNA signaling present challenges in developing CSC-specific therapeutics. Approaches to targeting CSCs include the development of agents targeting known stem cell regulatory pathways as well as unbiased high-throughput siRNA or small molecule screening. Based on studies of pathways present in normal stem cells, recent work has identified potential “Achilles heals” of CSC, whereas unbiased screening provides opportunities to identify new pathways utilized by CSC as well as develop potential therapeutic agents. Here, we review both approaches and their potential to effectively target breast CSC. [Copyright &y& Elsevier]

OBJECTIVE To analyse the durability of response for patients with non-muscle-invasive bladder cancer (NMIBC) refractory to bacille Calmette-Guérin (BCG) therapy and treated with intravesical docetaxel in a combined induction and maintenance regimen. PATIENTS AND METHODS A previous phase I trial showed docetaxel to be safe for intravesical therapy, with no systemic absorption and minimal toxicity after six weekly instillations for patients with BCG-refractory NMIBC. In that trial, docetaxel gave a 56% complete response (CR) rate at 12 weeks, but the durability was only 22%. Thus a second group of patients was treated with a 6-week induction and then given monthly maintenance therapy with intravesical docetaxel. Thirteen patients with BCG-refractory Ta, T1, or Tis transitional cell carcinoma were treated. Induction therapy was administered as six weekly intravesical instillations of 75 mg followed by single-dose monthly maintenance therapy for nine additional instillations in patients who had a CR. The initial response at 12 weeks from the start of induction therapy was evaluated by cystoscopy with biopsy, and urine cytology. The follow-up consisted of quarterly cystoscopy with biopsy and cytology, and periodic imaging. RESULTS The median follow-up was 13 months; 10 of 13 patients had a CR after induction, and six have remained disease-free during the follow-up. Of those in who the treatment failed, six had transurethral resection of the tumour and one a cystectomy. All 10 initial responders completed at least three instillations of maintenance therapy to date (median nine instillations), of whom six have remained recurrence-free. CONCLUSION Monthly maintenance therapy with intravesical docetaxel appears to extend the durability of response to induction treatment for a selected group of patients with BCG-refractory NMIBC, and might decrease the overall risk of recurrence in high-risk NMIBC. [ABSTRACT FROM AUTHOR]

Aurora kinases are potential targets for cancer therapy. Previous studies have validated Aurora kinase A as a therapeutic target in multiple myeloma (MM), and have demonstrated in vitro anti-myeloma effects of small molecule Aurora kinase inhibitors that inhibit both Aurora A and B. This study demonstrated that Aurora B kinase was strongly expressed in myeloma cell lines and primary plasma cells. The selective Aurora B inhibitor AZD1152-induced apoptotic death in myeloma cell lines at nanomolar concentrations, with a cell cycle phenotype consistent with that reported previously for Aurora B inhibition. In some cases, AZD1152 in combination with dexamethasone showed increased anti-myeloma activity compared with the use of either agent alone. AZD1152 was active against sorted CD138+ BM plasma cells from myeloma patients but also, as expected, was toxic to CD138− marrow cells from the same patients. In a murine myeloma xenograft model, AZD1152-inhibited tumour growth at well-tolerated doses and induced cell death in established tumours, with associated mild, transient leucopenia. AZD1152 shows promise in these preclinical studies as a novel treatment for MM. [ABSTRACT FROM AUTHOR]

A number of studies are being published on investigational agents for the treatment of patients with chronic hepatitis C. Before incorporating new medications into therapy or electing to postpone therapy until an investigational agent receives regulatory approval, it is important to evaluate the following specific features of the published evidence: quality of the evidence, precision of the treatment effect, magnitude of the treatment effect, magnitude of the hazards, and other factors such as risk-benefit analysis and cost, including cost-effectiveness. Previous studies of treatment of patients with the disease allow us to establish some benchmarks and provide structure to evaluate the evidence of the efficacy and safety of these newer drugs. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a plasma cell malignancy that claims thousands of lives each year and has considerable morbidity. The disease remains incurable despite recent advances in the understanding of the disease biology and the introduction of more effective drugs is needed. This study evaluated the anti-MM activity of 3-(7-fluoro-4H-quinazolin-3-yl)-piperidine-2,6-dione, hydrochloride (FQPD), a novel immunomodulatory drug. FQPD inhibited the proliferation of multiple MM cell lines, including those resistant to conventional treatments, such as dexamethasone. It induced apoptosis in MM cell lines, as well as freshly isolated patient MM cells, without cytotoxicity on normal human lymphocytes. Moreover, it induced apoptosis in MM cells adherent to bone marrow (BM) stromal cells or in the presence of cytokines, such as interleukin-6 and vascular endothelial growth factor, confirming its ability to overcome the protective effects of the BM milieu. Apoptosis in the MM cells was mediated via poly-ADP ribose polymerase cleavage as well as cleavage of caspase 8 and caspase 9. Our studies therefore demonstrated in vitro anti-MM activity of FQPD and provide the rationale for its in vivo evaluation in animal models and derived clinical trials. [ABSTRACT FROM AUTHOR]