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La leucémie lymphoïde chronique (LLC) est l'hémopathie maligne la plus fréquente des pays occidentaux. Elle se caractérise par une accumulation de cellules leucémiques dans le sang, la moelle osseuse et les organes lymphoïdes secondaires. Malgré les nouvelles thérapies, la LLC reste incurable. Dans la LLC, comme dans tout cancer, le microenvironnement tumoral, un milieu complexe contenant des cellules immunitaires pouvant être pro-tumorales, prend une part croissante aussi bien dans la physiopathologie que le pronostic. La recherche de nouvelles thérapies ciblant les interactions des cellules leucémiques avec ce microenvironnement représente aujourd'hui une piste prometteuse pour traiter cette pathologie. Les " nurse-like " cells (NLC) semblaient être les macrophages associés aux tumeurs (TAM) de la LLC. Ces cellules, retrouvées dans les ganglions lymphatiques de patients, favorisent in vitro la survie des cellules leucémiques. Elles partagent avec les TAM de nombreuses caractéristiques telles que des capacités immunosuppressives, un profil transcriptomique proche et une implication dans la résistance aux traitements. Nous l'avons confirmé par une analyse fonctionnelle et phénotypique. Nos travaux indiquent clairement que les NLC sont les TAM de la LLC avec une forte expression de CD68 et de CD163 et qu'elles favorisent la survie des cellules leucémiques. Suite à ce travail, nous avons déterminé l'impact pronostique des NLC dans la LLC, en émettant l'hypothèse que, comme dans d'autres cancers, une forte infiltration par les TAM pouvait être de mauvais pronostic. Nous avons alors montré que le taux de NLC présentes au sein du ganglion lymphatique chez le patient est corrélé à la progression de la LLC. Les NLC relarguent également un facteur soluble le CD163 soluble (sCD163) dans le sang des patients, dont le taux est corrélé à des marqueurs de mauvais pronostic dans la LLC tels que le statut IgHV non muté, le caryotype complexe et les mutations de TP53. Enfin, le taux de sCD163 est un marqueur pronostique indépendant dans la LLC : un fort taux étant associé à un raccourcissement du temps avant retraitement, de la survie sans progression et de la survie globale des patients. Ensuite nous avons étudié l'impact d'une thérapie innovante, l'ibrutinib, un inhibiteur de tyrosine kinase ciblant spécifiquement la Bruton Tyrosine Kinase, sur ces NLC. In vitro, les monocytes se différencient toujours en NLC et leur phénotype n'est pas modifié. De plus, ces cellules sont toujours capables de protéger les cellules leucémiques de l'apoptose. Finalement, nous avons mis en évidence qu'elles pouvaient participer à la chimiorésistance, en protégeant in vitro les cellules leucémiques de l'ibrutinib mais pas du dasatinib, de l'idélalisib, du vénétoclax, de la bendamustine et du rituximab. L'ensemble de nos résultats indique que cibler les NLC est une piste prometteuse dans le traitement de la LLC. Les interactions cellulaires entre NLC et cellules leucémiques pourraient représenter une cible thérapeutique intéressante. Nous avons montré qu'in vitro le contact entre NLC et cellules leucémiques est nécessaire à la survie de ces dernières. Suite à une étude transcriptomique, nous avons mis en évidence plusieurs couples moléculaires potentiellement impliqués dans ces interactions. Seul le couple LFA3/CD2 s'est révélé être nécessaire dans ce contact via un mécanisme dépendant d'Akt et son blocage inhibe totalement les effets pro-survie des NLC sur les cellules leucémiques. En conclusion, les NLC via des interactions dépendantes du couple LFA-3/CD2 protègent les cellules leucémiques de l'apoptose in vitro. De plus, elles participent à la chimiorésistance en protégeant aussi les cellules leucémiques de l'ibrutinib. Elles relarguent également du sCD163, dosable dans le sérum, un facteur pronostique indépendant de la LLC. La recherche de nouvelles thérapies plus spécifiques, ciblant les NLC constitue donc une piste thérapeutique intéressante dans la LLC. / Chronic lymphocytic leukemia (CLL) is the most common hemopathy in western countries. This pathology is characterized by an accumulation of leukemic cells in blood, bone marrow and secondary lymphoid organs. Despite new therapies, CLL is still incurable. In CLL, the microenvironment, a complex media containing immune cells witch can favor the tumor, takes now a large place in the physiopathology and the prognosis. The research of new therapies targeting interactions between CLL cells and microenvironment is a promising runway to find new drugs in CLL. "Nurse-like" cells (NLC) should be the tumor associated macrophages (TAM) of CLL. This cells, found in the lymph node of CLL patients, protect CLL cells against in vitro apoptosis. They share with TAM many characteristics including immunosubversive proprieties chemoresistance induction and a close gene expression profiling. We confirmed that by functional and phenotypical analysis. Our results indicate that NLC are the TAM of CLL with a high expression of CD68 and CD163 and that NLC can protect CLL cells against in vitro apoptosis. Thus, we focused on the clinical impact of NLC in CLL. Because in several cancers a high infiltration of TAM is correlated with a poor clinical outcome, we hypothesized that NLC infiltration should be associated with CLL outcome. We showed that infiltration of NLC in the lymph node can be correlated with the progressivity of CLL. Moreover, NLC release a soluble factor, the sCD163 (soluble sCD163), in the blood of CLL patients. High levels of this factor, can be correlated with previously established prognostic makers in CLL such as TP53 mutations, unmutatted IgHV status and complex karyotype. Finally, sCD163 was an independent prognostic marker in CLL and high levels are associated with shorter time to next treatment, progression free survival and overall survival. Next, we studied the impact of ibrutinib, a new therapy in CLL, on NLC. Ibrutinib is a specific tyrosine kinase inhibitor witch targets specifically the Bruton Tyrosine Kinase. In vitro, NLC differentiated from ibrutinib treated patients have the same phenotype as NLC from untreated patients and are still able to protect CLL cells against apoptosis. To end, we tested if in vitro NLC could protect CLL cells against chemotherapy and showed that NLC protect CLL cells against ibrutinib but not against idelalisib, dasatinib, venetoclax, bendamustin and rituximab. All our previous studies reveal that NLC are a good target to find new therapies in CLL. We focused our work on the interaction between NLC and CLL cells. First, we demonstrated that the NLC/CLL cells contact is necessary to prevent CLL cells death in vitro. Next, by gene expression profiling, we screened several couple of molecules potentially implicated in these interactions. Finally, only LFA-3/CD2 couple was necessary for this contact through an Akt pathway dependent and the inhibition of this couple totally inhibited the pro-survival effect of NLC on CLL cells. To conclude, NLC protect CLL cells from in vitro apoptosis through LFA-3/CD2. Moreover, they protect CLL cells against ibrutinib and so facilitate the chemoresistance. They release sCD163, an independent marker in CLL, which can be measured in the serum. The research of new targets, which can be considerate as more specific, targeting NLC is still an interesting way to find new therapies in CLL.

Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Lucie Čermáková Supervisor: RNDr. Eva Novotná, Ph.D. Title of diploma thesis: The effect of acalabrutinib and ibrutinib on the efficacy of daunorubicin in cancer cells Leukemia presents malignant diseases of hematopoiesis, which essence is the malignant transformation of a hematopoietic stem cell at various levels of maturation and increased proliferative activity. Chemotherapy is the gold standard in the treatment of leukemia. One of the many treatments is the use of anthracycline chemotherapeutics, especially daunorubicin (DAU). Anthracyclines are widely used in clinical practice but have high cardiotoxic effects that limit their dosage. One of the main causes of side effects is the reduction of an anthracycline chemotherapeutic to the appropriate toxic metabolite, which accumulates in the heart. Carbonyl, reducing enzymes from the superfamily aldo-ketoreductase (AKR), and short-chain dehydrogenase/reductase (SDR) are involved in this reduction. At the same time, carbonyl reducing enzymes, has been shown to be involved in the mechanisms that cause tumor cells to be resistant to anthracyclines, thereby reducing the inhibition of the growth of these cells. In the diploma thesis we found that...

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Ibrutinib is the first Bruton`s tyrosine kinase (BTK) inhibitor for oral administration approved by FDA in 2014. It is the first-line treatment for B-cell malignancies, which are the most common hematologic neoplasia. Ibrutinib is a relatively safe alternative for currently used treatment modalities that are associated with long-term toxicity and resistance. However, ibrutinib is considered as BCS class II drug and has very low solubility in an aqueous medium (13 μg/ml at PH 8.0) and has six different polymorphic forms. Furthermore, recommended daily dose of ibrutinib is about 420 mg to 560 mg, which causes severe GI disturbances, with poor patient compliance. This represent a major critical concern because drug is used chronically. Increasing drug solubility and controlling rate of drug release may improve both bioavailability at significantly lower daily administered doses and by implication could minimize GI side effects and improve patient compliance.The objective of this study is to utilize Hot Melt Extrusion (HME) to develop a stable amorphous solid dispersion (ASD) of ibrutinib using Copovidone (PlasdoneTM S-630 Ultra) as a carrier for inclusion into a hydrating matrix for sustained release delivery. Development of ASD based on HME is an efficient method to overcome poor solubility problem and stabilize the drug`s metastable polymorphic states. It is known that amorphous systems are energetically at a higher thermodynamic state and can dissolve to a much greater extent relative to their crystalline counterpart. A stable sustained-release ASD based system may offer many advantages, including reduction in frequency of administration and GI disturbances with propensity to enhance solubilization while suppressing recrystallization. The ASD systems prepared in this study was stable, amorphous, and single-phase systems up to 60% API load as confirmed by X-ray powder diffraction (XRPD), modulated differential scanning calorimetry (mDSC), and rheological analysis. Supersaturated micro-dissolution testing of melt-extruded powder in fasted state simulated intestinal fluid demonstrated up to 70% increase in supersaturation solubility than the saturation solubility of crystalline counterparts. In addition, dissolution data based on the standard USP paddle method for the formulated SR tablets demonstrated a prolonged release up to six hours and a maximum of 53% higher drug release than crystalline ibrutinib. In conclusion, the results of this study indicate that ibrutinib amorphous solid dispersion developed utilizing hot-melt extrusion technology and Copovidone (PlasdoneTM S-630 Ultra) as a carrier is able to produce stable and homogeneous single-phase ASD system with enhanced solubility and desirable sustained drug release rate. / Pharmaceutical Sciences

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