Tetrahydroisoquinoline alkaloids are a class of structurally complex natural products and a huge number of its natural product widely exist in nature which, from the discovery has been more than a century, it compounds with high anti-tumor activity, antibacterial and other physical activity, but also because of its special structure, with low oncentration of biological activity, but these alkaloids are not sold in the market mainly due to a less natural extraction, chemical synthesis method and multi-step, low yield. Therefore, we constructed a combination of tetrahydroisoquinoline alkaloids and the pyrazino [2,1-b] quinazoline-3,6-diones structure of the new compounds, which have the quinazolinone compounds which is the drug synthesis and drug activity on the bond, is also a kind of unique and widely used drug structure, and causes a lot of scientists and drug research interest and discussion, as we develop the motivation.

No description available.

T-cells are lymphocytes that make up part of the adaptive arm of the immune system, and are essential for efficient protection from and eradication of viruses and pathogens. T-cells not only play an important role in protection from external agents, but also regulate and prevent activation towards self-peptides and detect and remove erratically growing cells. Alterations in T-cell activation and suppression contribute to auto-immunity, immunocompromised disorders, and cancer progression. The immune system, and T-cells in particular, provides daily surveillance, recognition and destruction of aberrant cells. Although the immune system is proficient at suppressing malignant progression, tumor cells acquire various methods of immune evasion. Myelodysplastic Syndrome (MDS) is a pre-malignant dysplastic disorder of the bone marrow characterized by ineffective hematopoiesis and clonality in the myeloid lineage, where lack of immune response has been implicated in the propensity for progression to acute myeloid leukemia (AML). Leukemia progression is associated with the acquisition of complex genetic abnormalities. Alterations in immune system regulation have been implicated in various stages of the disease process, although the role of the immune system in response to several therapies in MDS has not been fully discovered. Lenalidomide is a small molecule therapeutic preferentially effective in MDS patients with an interstitial chromosome 5q deletion (del(5q)). Improved erythropoiesis has also been reported to occur in 20-30% of low-risk, non-del(5q) patients. Although lenalidomide is a potent immunomodulatory drug that potentiates T-cell and NK-cell responses, the T-cell compartment in MDS is highly deregulated by aberrant repertoire skewing, decreased function and abnormal naïve and memory cell homeostasis. The presence of lymphoid infiltrates in the bone marrow of lenalidomide-responsive patients suggests that T-cells may participate in the hematopoietic response, but it is unclear if lenalidomide is capable of reversing these functional T-cell defects. We therefore assessed immunological changes in low-risk MDS patients before and after 16-weeks of lenalidomide therapy, and assessed the relationship to erythroid response. Although MDS T-cells were anergic prior to treatment, we have shown that T-cells in responders have a significant increase in antigen-induced proliferative response and T helper type-1 (Th1) cytokine production (IL-2, IFN-γ, TNF-α) compared to non-responders. The change in function positively correlated with an increase in naïve T-cells and a decrease in memory cells, indicating that lenalidomide has immunomodulatory activity to reverse anergy in MDS. Although it is known that lenalidomide may increase T-cell activation and proliferation in the absence of co-stimulatory signals, a direct mechanism of action has yet to be elucidated. Since CD28 is one of the most important co-stimulatory molecules deregulated in cancer, we therefore set out to determine if the expression of CD28 was essential for lenalidomide's mechanism in T-cells. We knocked out CD28 expression in healthy donor T-cells, and sorted on inherently deficient, CD28null, T-cells that accumulate in older healthy donors and found that lenalidomide-induced proliferation and function were completely ablated within the CD28null subset. These data indicate the immunotyrosine-based activation motifs (ITAMs) on the intracellular domain of the CD28 receptor are necessary for lenalidomide action. Interestingly, during the natural aging process, repeated exposure to antigens results in the accumulation of CD28null T-cells that are phenotypically distinct and functionally deficient due to excessive proliferative history in vivo. We therefore examined whether CD28 expression on MDS patient T-cells affected responses to lenalidomide, and if this could be used as a predictive biomarker of responsiveness. We found that patients who fail lenalidomide therapy had higher CD8+ Terminal Effector Memory (TEM), which are inherently CD28null, and that non-responders had an overall increase in CD4+ and CD8+CD28null T-cells, as well as an increase in CD28null cells within the TEM compartment compared to hematologic responders. We then sought to determine the particular protein target of lenalidomide responsible for increased CD28 receptor signaling in T-cells. Several targets in a variety of cell types have been postulated, although the direct mechanism in T-cells is unclear. Our group has previously shown that lenalidomide inhibits the activity of two haplodeficient phosphatases located within the commonly deleted region (CDR) on chromosome 5q in the MDS myeloid clone, Protein Phosphatase 2A (PP2A) and Cdc25c. PP2Ac is known to bind CD28 and is hypothesized to inhibit T-cell co-stimulation. Therefore, it is plausible that lenalidomide and other IMiDs inhibit the phosphatase activity of PP2A which leads to increased activation of T-cell proximal signals dependent on CD28 expression. We examined this hypothesis using molecular modeling and virtual screening and found that all of the IMiDs (lenalidomide, pomalidomide, and thalidomide) can theoretically interact with the catalytic pocket of the PP2A heterotrimer, potentially inhibiting PP2Ac activity. In vitro phosphatase activity assays supported these findings as lenalidomide-inhibition of PP2Ac activity was seen in both ad293 and Jurkat cell lines, and in primary T-cells. Mutations of theorized lenalidomide hydrogen-bond sites within the catalytic pocket of PP2A rendered the enzyme catalytically dead, indicating that these are important residues for enzymatic activity, but unfortunately could not be used to determine if lenalidomide activity was disrupted by mutation of those sites. These data together suggest that the ability of lenalidomide to augment immune activation in vivo in MDS patients, and potentially other diseases, is extremely important to patient response. Also, that CD28 expression on T-cells is essential for lenalidomide immune-mediated tumor eradication through CD28 downstream signaling, and potentially through inhibition of PP2A. These results are useful in designing future lenalidomide-combination therapy trials in other hematologic and solid malignancies, and could be used to help stratify patients for future therapeutic decisions in MDS and other malignancies.

PURPOSE: This phase I dose-escalation study was undertaken to establish the maximum tolerated dose of the sequence-selective minor groove DNA binding agent SJG-136 in patients with advanced solid tumors. The study also investigated antitumor activity and provided pharmacokinetic and pharmacodynamic data. EXPERIMENTAL DESIGN: Sixteen patients were assigned sequentially to escalating doses of SJG-136 (15-240 microg/m(2)) given as a 10-minute i.v. infusion every 21 days. The dose was subsequently reduced in incremental steps to 45 microg/m(2) due to unexpected toxicity. RESULTS: The maximum tolerated dose of SJG-136 was 45 microg/m(2). The main drug-related adverse event was vascular leak syndrome (VLS) characterized by hypoalbuminemia, pleural effusions, ascites, and peripheral edema. Other unexpected adverse events included elevated liver function tests and fatigue. The VLS and liver toxicity had delayed onset and increased in severity with subsequent cycles. Disease stabilization was achieved for >6 weeks in 10 patients; in 2 patients this was maintained for >12 weeks. There was no evidence of DNA interstrand cross-linking in human blood lymphocytes with the use of the comet assay. Evidence of DNA interaction in lymphocytes and tumor cells was shown through a sensitive gamma-H2AX assay. SJG-136 had linear pharmacokinetics across the dose range tested. CONCLUSIONS: SJG-136 was associated with dose-limiting VLS and hepatotoxicity when administered by short injection every 21 days. DNA damage was noted, at all dose levels studied, in circulating lymphocytes. The etiology of the observed toxicities is unclear and is the subject of further preclinical research. Alternative clinical dosing strategies are being evaluated.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / The Hasumi vaccine (VH) is an imune-stimulant mode by two preparations obtained from distinctive forms, it is an assisting in a pool of tumours antigens. The assisting is taken off from calf splens and the antigen, from different forms of tumor. The VH is a sterile uncoloured liquid, conditioned in 0,5mL glass ampoules, separately. The present research aimed to evaluate, throughout a Phase I study, the security of VH, as well as the comprehension of its action mechanism. The clinical experiment was conducted in 24 healthy volunteers in wich the VH was given subcutaneously every 5 days during 2 months, accomplishing an amount in wich the two first ones were given in the hospital. Before the first administration, all the voluteers did the Prick test, to evaluate the possibility of reacting to hipersensibility. After that they were submit to clinical and laboratorial evaluation (hemogram, biochemical, urine extract and parasitological excrements exams, sorology to B and C hepatitis, HIV, FAN, reumatoidic factor, C3, CD3, CD4, CD8, IgA, IgG, IgE, IgM, PSA, CEA, AFP and HCG-beta). The planning of the experiment also had the repetition of such exams after the 3th, 6th and the 12th doses, as well as in the after-study 30 days after the last dose. By hte and of the study, significant adverse events were not observed. Therefore, in the last dose and within the stabilished treatment period of this experiment, the VH was shown to be safe and with no toxity. / A Vacina Hasumi (VH) à um imuno estimulante constituÃdo por duas preparaÃÃes obtidas de formas distintas, sendo um adjuvante e um pool de antÃgenos tumorais. O adjuvante à retirado de cÃlulas de baÃo de bezerros e o antÃgeno, de diversas formas de tumor. A VH à um lÃquido incolor estÃril, acondicionado em ampolas de vidro, no volume de 0,5mL, separadamente. O presente trabalho objetivou avaliar, atravÃs de um Estudo de Fase I, a seguranÃa da VH, bem como a compreensÃo do seu mecanismo de aÃÃo. O ensaio clÃnico foi conduzido em 24 voluntÃrios sadios nos quais a VH foi administrada por via subcutÃnea a cada 5 dias durante 2 meses, perfazendo um total de 12 administraÃÃes, sendo as 2 primeiras em regime de internamento hospitalar. Antes da primeira administraÃÃo, todos os voluntÃrios realizaram o prick teste, para avaliar a possibilidade de reaÃÃo de hipersensibilidade, apÃs o que, foram submetidos a avaliaÃÃes clÃnica e laboratorial (hemograma completo, bioquÃmica, sumÃrio de urina, parasitolÃgico de fezes, sorologia para hepatite B e C, HIV, FAN, fator reumatÃide, C3, CD3, CD4, CD8, IgA, IgG, IgE, IgM, PSA, CEA, AFP, Beta HCG). O planejamento do experimento compreendeu tambÃm a repetiÃÃo das avaliaÃÃes apÃs a 3a, 6a e a 12a doses e no pÃs-estudo, 30 dias apÃs a Ãltima dose. Ao final do estudo nÃo foram observados eventos adversos significantes. Portanto, na dose e no tempo de tratamento estabelecidos neste ensaio, a VH mostrou-se segura e nÃo apresentou toxicidade.

Le ciblage de l’activité de l’IFNα est une stratégie développée afin d’augmenter l’index thérapeutique de cette cytokine, dont l’efficacité requiert de fortes doses au site d’action, responsables d’une toxicité systémique. Du fait de l’expression ubiquitaire de son récepteur, le ciblage de l’IFNα par immunocytokine est limité. En se basant sur le concept d'immunocytokine et utilisant un IFNα muté, peu actif, une efficacité de ciblage de 3 log a pu être obtenue, dans le système humain et murin, grâce au rétablissement de l'activité de l'IFNα sur les cellules ciblées. Ces IFNα ciblés sont doués d'une activité biologique, notamment antitumorale, dont la cible cellulaire reste à déterminer. Une stratégie inverse, en cours d'optimisation, permet d'inhiber l’activité des IFN-I spécifiquement sur les cellules ciblées. Cette double stratégie de ciblage de l’activité et de l’inhibition de l’IFN devrait permettre de déterminer les cibles des effets bénéfiques et néfastes des IFN-I, avec des applications thérapeutiques éventuelles. / Targeting IFN activity is a strategy developed to increase the therapeutic index of thiscytokine, whose efficiency requires high doses to site of action, responsible for systemictoxicity. Due to the ubiquitous expression of its receptor, the targeting efficiency of IFNbasedimmunocytokine is limited. Using a mutated IFNα, poorly active, a 3 log targetingefficiency was achieved, in the human and mouse system, by restoring the activity of IFNα ontargeted cells. The biological activity of these targeted IFNα include an antitumoral effect,the cellular target remains to be determined. A reverse strategy being optimized, can inhibitIFN-I activity specifically on targeted cells. This dual targeting strategy of the activity andinhibition of IFN should identify the targets of beneficial and deleterious effects of IFN-I,with possible therapeutic applications.

No description available.

The heterogeneity of pancreatic cancer renders many available general therapies ineffective holding the five-year survival rate close to 10% for decades. Surgical resection eligibility, resistance to chemotherapy and limited efficacy of immunotherapy emphasize the dire need for diverse and innovative treatments to combat this challenging disease. This study evaluates co-therapy strategies that combine non-thermal, minimally invasive ablation technology and targeted drug delivery to enhance treatment efficacy. Our research begins by uncovering the multifaceted potential of Irreversible Electroporation (IRE), a cutting-edge non-thermal tumor ablation technique. This study demonstrates IRE-mediated ability to trigger programmed necrotic cell death, induce cell cycle arrest, and modulate immune cell populations within the tumor microenvironment. This transformation from a pro-tumor state to a proinflammatory milieu, enriched with cytotoxic T lymphocytes and neutrophils. IRE-induced proinflammation in the tumor site renders immunologically "cold" tumor into immunologically "hot" tumor and holds significant promise of improving treatment efficacy. Notably, IRE-treated mice exhibited an extended period of progression-free survival, implying clinical potential. The transient nature of these effects suggests potential mechanisms of tumor recurrence highlighting the need for further studies to maximize the efficacy of IRE. Our mechanistic studies evaluated the IFN-STAT1-PD-L1 feedback loop as a possible reason for pancreatic tumor recurrence. Our data also suggest a stronger IFN-PD-L1 feedback loop compared to mammary, osteosarcoma and glioblastoma tumors rendering pancreatic cancer immunologically "cold". This study also investigates the use of histotripsy (a non-thermal, noninvasive, nonionizing ultrasound-guided ablation modality) to treat pancreatic cancer utilizing a novel immunocompromised swine model. We successfully generated human orthotopic pancreatic tumors in the immune deficient pigs, which allowed for consequent investigation of clinical challenges presented by histotripsy. While rigorous clinical studies are indispensable for validation, the promise of histotripsy offers new hope for patients. In parallel, we used our immunocompromised swine model of orthotopic pancreatic cancer to investigate the SonoTran® system, which employs ultrasound-activated oscillating particles to enhance drug delivery within hard-to-reach tumors. Our study demonstrates that SonoTran® significantly enhances the intratumoral penetrance of therapeutic agents, including commonly used chemotherapy drugs like paclitaxel and gemcitabine. Additionally, SonoTran® improved delivery of the anti-epidermal growth factor (EGFR) monoclonal antibody, cetuximab- which is frequently used in cancer immunotherapy. Together, our findings address challenges in the delivery of a range of therapeutics while simultaneously exposing challenges like off-target damage. In conclusion, this study presents a multifaceted approach to confront the complex characteristics of pancreatic cancer. Given the variations in patient response and the complexity of the disease, it is clear that a singular solution is unlikely. Our research, which combines IRE, histotripsy, and SonoTran®, to interrogate a promising array of tools to tackle different challenges to provide tailored treatments. In the ever-evolving landscape of pancreatic cancer therapy, this research opens new avenues to investigate deeper into molecular mechanisms, co-therapy treatment options, future preclinical and clinical studies which eventually encourage the potential for improved patient outcomes. / Doctor of Philosophy / Pancreatic cancer is a formidable disease, known for its late-stage diagnosis and limited treatment options with a poor 5-year survival rate of ~10%. However, a promising frontier in the battle against this lethal disease has emerged through combining mechanical, cell based and immunotherapies to attack the cancer from multiple angles at once. In my PhD research, I explored novel approaches to transform the landscape of pancreatic cancer treatment. We began by investigating Irreversible Electroporation (IRE), a non-thermal method to ablate tumors. Beyond its known function of reducing tumor size, IRE initiated programmed necrotic cell death, halted tumor cell division, and triggered changes in the immune landscape within the tumor. In response to IRE treatment, the immune environment shifted from pro-tumor to proinflammatory state, showing potential for clinical use. Mice treated with IRE experienced extended cancer progression-free survival temporarily, followed by eventual relapse. During relapse, we found that immune cells reverted back to their original, pre- IRE treated state. This observation logically implies combining IRE and immune checkpoint inhibitors aimed towards maintaining the IRE-altered immunological environment. Next, we developed and used novel pig models that closely resemble human pancreatic cancer patients to test histotripsy, a first phase toward making histotripsy as a non-invasive treatment approach for pancreatic cancer. Use of orthotopic tumor in a large animal model and clinical device allowed us to expose some challenges of ultrasound guidance of histotripsy. Notably, the treatment results in partial ablation and a reduction in stroma materials, which play a role in the tumor's resistance to commonly used treatments. While rigorous clinical studies are needed for validation, this approach offers hope in the quest for innovative pancreatic cancer treatment. Another promising approach we investigated involves SonoTran® particles, ultrasound-activated oscillating particles that can increase drug absorption in a targeted fashion. Our study demonstrated increased concentrations of commonly used therapeutic agents within tumors through SonoTran®-facilitated delivery, providing an effective means to overcome drug delivery issues within pancreatic tumors. There is no one size fits all treatment to address the complexity of pancreatic cancer. The future of treatment lies in the integration of IRE, histotripsy and SonoTran® into clinical practice. In summary, this PhD research identified promising novel technologies and combinations of treatments for pancreatic cancer, reaffirming the importance of exploring innovative solutions to combat pancreatic cancer. The dynamic nature of the pancreatic tumor microenvironment underscores the importance of further research to extend the positive impacts of these treatments and improve tumor debulking.

No description available.

No / Inadequate drug delivery to tumours is now recognised as a key factor that limits the efficacy of anticancer drugs. Extravasation and penetration of therapeutic agents through avascular tissue are critically important processes if sufficient drug is to be delivered to be therapeutic. The purpose of this study is to develop an in silico model that will simulate the transport of the clinically used cytotoxic drug doxorubicin across multicell layers (MCLs) in vitro. Three cell lines were employed: DLD1 (human colon carcinoma), MCF7 (human breast carcinoma) and NCI/ADR-Res (doxorubicin resistant and P-glycoprotein [Pgp] overexpressing ovarian cell line). Cells were cultured on transwell culture inserts to various thicknesses and doxorubicin at various concentrations (100 or 50 microM) was added to the top chamber. The concentration of drug appearing in the bottom chamber was determined as a function of time by HPLC-MS/MS. The rate of drug penetration was inversely proportional to the thickness of the MCL. The rate and extent of doxorubicin penetration was no different in the presence of NCI/ADR-Res cells expressing Pgp compared to MCF7 cells. A mathematical model based upon the premise that the transport of doxorubicin across cell membrane bilayers occurs by a passive "flip-flop" mechanism of the drug between two membrane leaflets was constructed. The mathematical model treats the transwell apparatus as a series of compartments and the MCL is treated as a series of cell layers, separated by small intercellular spaces. This model demonstrates good agreement between predicted and actual drug penetration in vitro and may be applied to the prediction of drug transport in vivo, potentially becoming a useful tool in the study of optimal chemotherapy regimes.