Tazemetostat synergistically combats multidrug resistance by the unique triple inhibition of ABCB1, ABCC1, and ABCG2 efflux transporters in vitro and ex vivo.

ATP-binding cassette (ABC) drug efflux transporters and drug metabolizing enzymes play crucial roles in pharmacokinetic drug-drug interactions and multidrug tumor resistance (MDR). Tazemetostat (EPZ-6438, Tazverik) is a novel epigenetic drug that has been recently approved for the therapy of advanced epithelioid sarcoma and follicular lymphoma. Additionally, this medication is currently being clinically tested to treat several other cancers such as non-small cell lung cancer (NSCLC). This study aimed to investigate the inhibitory effects of tazemetostat on selected ABC transporters/cytochrome P450 3A4 (CYP3A4) enzyme to comprehensively explore its role in MDR. First, our accumulation and molecular docking studies showed that tazemetostat is a unique triple inhibitor of ABCB1, ABCC1, and ABCG2 transporters. In contrast, tazemetostat exhibited only low level of interaction with the CYP3A4 isozyme. Drug combination assays confirmed that tazemetostat is a multipotent MDR modulator able to synergize with various conventional chemotherapeutics in vitro. Subsequent caspase activity assays and microscopic staining of apoptotic nuclei proved that the effective induction of apoptosis is behind the observed synergies. Notably, a potent MDR-modulatory capacity of tazemetostat was recorded in primary ex vivo NSCLC explants generated from patients' biopsies. On the contrary, its possible position of pharmacokinetic MDR's victim was excluded in comparative proliferation assays. Finally, tested drug has not been identified as an inducer of resistant phenotype in NSCLC cell lines. In conclusion, we demonstrated that tazemetostat is a unique multispecific chemosensitizer, which has strong potential to overcome limitations seen in the era of traditional MDR modulators.

Therapeutic effect of lymphography in the postoperative chylothorax - case reports and literature review.

Postoperative chylothorax is a well-known rare complication of thoracic surgery. It is a serious complication that is fatal in cases of inadequate treatment. The authors present 2 cases of postoperative chylothorax that were successfully treated by performing pedal and/or intranodal lymphography. In one case, the patient underwent lymphography after previous unsuccessful surgical ligation of the thoracic duct. The presented case reports describe therapeutic importance of conventional lymphography as a minimally invasive treatment of the postoperative chylothorax.

Encorafenib Acts as a Dual-Activity Chemosensitizer through Its Inhibitory Effect on ABCC1 Transporter In Vitro and Ex Vivo.

Encorafenib (LGX818, trade name Braftovi), a novel BRAF inhibitor, has been approved for the treatment of melanoma and colorectal cancer. In the present work, we evaluated encorafenib's possible antagonistic effects on the pharmacokinetic mechanisms of multidrug resistance (MDR), as well as its perpetrator role in drug interactions. Firstly, encorafenib potently inhibited the efflux function of the ABCC1 transporter in drug accumulation assays, while moderate and null interaction levels were recorded for ABCB1 and ABCG2, respectively. In contrast, the mRNA expression levels of all the tested transporters were not altered by encorafenib. In the drug combination studies, we found that daunorubicin and topotecan resistances were synergistically attenuated by the encorafenib-mediated interaction in A431-ABCC1 cells. Notably, further experiments in ex vivo patient-derived explants confirmed the MDR-modulating ability of encorafenib. Advantageously, the overexpression of tested drug efflux transporters failed to hinder the antiproliferative activity of encorafenib. In addition, no significant modulation of the CYP3A4 enzyme's activity by encorafenib was observed. In conclusion, our work indicated that encorafenib can act as an effective chemosensitizer targeting the ABCC1-induced MDR. Our in vitro and ex vivo data might provide valuable information for designing the novel effective scheme applicable in the clinical pharmacotherapy of BRAF-mutated/ABCC1-expressing tumors.

Talazoparib Does Not Interact with ABCB1 Transporter or Cytochrome P450s, but Modulates Multidrug Resistance Mediated by ABCC1 and ABCG2: An in Vitro and Ex Vivo Study.

Talazoparib (Talzenna) is a novel poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitor that is clinically used for the therapy of breast cancer. Furthermore, the drug has shown antitumor activity against different cancer types, including non-small cell lung cancer (NSCLC). In this work, we investigated the possible inhibitory interactions of talazoparib toward selected ATP-binding cassette (ABC) drug efflux transporters and cytochrome P450 biotransformation enzymes (CYPs) and evaluated its position in multidrug resistance (MDR). In accumulation studies, talazoparib interacted with the ABCC1 and ABCG2 transporters, but there were no significant effects on ABCB1. Furthermore, incubation assays revealed a negligible capacity of the tested drug to inhibit clinically relevant CYPs. In in vitro drug combination experiments, talazoparib synergistically reversed daunorubicin and mitoxantrone resistance in cells with ABCC1 and ABCG2 expression, respectively. Importantly, the position of an effective MDR modulator was further confirmed in drug combinations performed in ex vivo NSCLC patients-derived explants, whereas the possible victim role was refuted in comparative proliferation experiments. In addition, talazoparib had no significant effects on the mRNA-level expressions of MDR-related ABC transporters in the MCF-7 cellular model. In summary, our study presents a comprehensive overview on the pharmacokinetic drug-drug interactions (DDI) profile of talazoparib. Moreover, we introduced talazoparib as an efficient MDR antagonist.

Surgical treatment of primary cardiac tumors: 20-year single center experience.

Introduction: Primary cardiac tumors are a rare condition presenting with a variety of symptoms. The outcomes of their surgical treatment in the modern era from central Europe have not been recently reported. Aim: To evaluate the short- and long-term outcomes of the cardiac tumor operations at our department throughout the last 20 years. Material and methods: This was a retrospective analysis of all primary cardiac tumor operations performed at our institution between 2000 and 2020. Perioperative data were extracted from patient records. Long-term data were provided by the National Registry of Cardiac Surgery. Results: Sixty procedures for primary cardiac tumor were performed throughout the study period. The most common type of tumor was myxoma (88%), followed by fibroelastoma (8%), lipoma (2%) and sarcoma (2%). There were 2 perioperative deaths (3%). The most common perioperative complication was atrial fibrillation (47%). One (2%) patient underwent reoperation 6 years later because of myxoma recurrence. We recorded 13 long-term deaths, but only 1 patient died as a consequence of cardiac tumor (sarcoma) 15 months after the surgery. Long-term survival of the cohort was comparable with the age- and sex-matched general population up to 15 years postoperatively (relative survival 0.91, CI 0.68-1.23). Rich histopathological illustrations are provided in the online supplementary material. Conclusions: Surgical resection is the standard treatment of primary cardiac tumors. The outcomes of benign tumors are excellent and the long-term postoperative survival is comparable with the general population. The prognosis of malignant tumors remains poor.

Sonidegib potentiates the cancer cells' sensitivity to cytostatic agents by functional inhibition of ABCB1 and ABCG2 in vitro and ex vivo.

Sonidegib (LDE-225) is a Hedgehog pathway inhibitor used for the therapy of basal cell carcinoma. In addition, the drug is a subject of clinical trials for the treatment of other solid tumors including non-small cell lung cancer (NSCLC). In this study, we explored the potential of sonidegib to act as a perpetrator of drug-drug interactions (DDIs) and modulator of transporter- and enzyme-mediated multidrug resistance (MDR). First, we found that transport functions of ABCB1 and ABCG2 were effectively inhibited by sonidegib in accumulation studies. In contrast, the drug did not cause fluctuations in mRNA levels of tested efflux transporters. In drug combination assays, sonidegib synergistically enhanced the cytotoxicity of daunorubicin and mitoxantrone in ABCB1- and ABCG2-overexpressing cells, respectively. Notably, similar phenomena were also observed in explant tumor cultures derived from NSCLC-suffering patients. In addition, the anticancer effects of sonidegib were not hampered by the expression of the ABC transporters associated with MDR. Last, sonidegib had no significant influence on the activity of CYP3A4 isoform in vitro. In summary, our work suggests that sonidegib can be considered a potential perpetrator of clinical DDIs on ABCB1 and ABCG2. After in vivo evaluation, its chemosensitizing properties might be projected into efficient and safe treatment regimen for the clinical management of NSCLC patients with high ABCB1/ABCG2 expression.

Tepotinib Inhibits Several Drug Efflux Transporters and Biotransformation Enzymes: The Role in Drug-Drug Interactions and Targeting Cytostatic Resistance In Vitro and Ex Vivo.

Tepotinib is a novel tyrosine kinase inhibitor recently approved for the treatment of non-small cell lung cancer (NSCLC). In this study, we evaluated the tepotinib's potential to perpetrate pharmacokinetic drug interactions and modulate multidrug resistance (MDR). Accumulation studies showed that tepotinib potently inhibits ABCB1 and ABCG2 efflux transporters, which was confirmed by molecular docking. In addition, tepotinib inhibited several recombinant cytochrome P450 (CYP) isoforms with varying potency. In subsequent drug combination experiments, tepotinib synergistically reversed daunorubicin and mitoxantrone resistance in cells with ABCB1 and ABCG2 overexpression, respectively. Remarkably, MDR-modulatory properties were confirmed in ex vivo explants derived from NSCLC patients. Furthermore, we demonstrated that anticancer effect of tepotinib is not influenced by the presence of ABC transporters associated with MDR, although monolayer transport assays designated it as ABCB1 substrate. Finally, tested drug was observed to have negligible effect on the expression of clinically relevant drug efflux transporters and CYP enzymes. In conclusion, our findings provide complex overview on the tepotinib's drug interaction profile and suggest a promising novel therapeutic strategy for future clinical investigations.

Uniportal video-assisted thoracic surgery lobectomy: a consensus report from the Uniportal VATS Interest Group (UVIG) of the European Society of Thoracic Surgeons (ESTS).

OBJECTIVES: Our goal was to report the results of the first consensus paper among international experts in uniportal video-assisted thoracoscopic surgery (UniVATS) lobectomy obtained through a Delphi process, the objective of which was to define and standardize the main procedural steps, optimize its indications and perioperative management and identify elements to assist in future training. METHODS: The 40 members of the working group were convened and organized on a voluntary basis by the Uniportal VATS Interest Group (UVIG) of the European Society of Thoracic Surgeons (ESTS). An e-consensus finding exercise using the Delphi method was applied to require 75% agreement for reaching consensus on each question. Repeated iterations of anonymous voting continued for 3 rounds. RESULTS: Overall, 31 international experts from 18 countries completed all 3 rounds of questionnaires. Although a technical quorum was not achieved, most of the responders agreed that the maximum size of a UniVATS incision should be ≤4 cm. Agreement was reached on many points outlining the currently accepted definition of a UniVATS lobectomy, its indications and contraindications, perioperative clinical management and recommendations for training and future research directions. CONCLUSIONS: The UVIG Consensus Report stated that UniVATS offers a valid alternative to standard VATS techniques. Only longer follow-up and randomized controlled studies will predict whether UniVATS represents a valid alternative approach to multiport VATS for major lung resections or whether it should be performed only in selected cases and by selected centres. The next step for the ESTS UVIG is the establishment of a UniVATS section inside the ESTS databases.

[Treatment of 14 cases of Castlemans disease: the experience of one centre and an overview of literature]. / Lécba 14 prípadu Castlemanovy nemoci: zkusenosti jednoho centra a prehled literatury.

Castlemans disease is the term for reactive lymphocytary and plasmocytary proliferation which occurs in the unicentric (localized) form, usually without systemic symptoms, or in the generalized/multicentric form, typically with systemic symptoms (www.vzacne-diagnozy.cz). Over the past 25 years we diagnosed, treated and followed 14 histologically proven cases of Castlemans diseases. Seven patients had the localised form of the disease. In 5 of 7 cases the pathological lesion was located intrathoracically or intraabdominally and in only 2 cases it was on the surface of the body. No clinical symptoms were present in any of the patients with the unicentric form of the disease and surgical treatment led to the total removing of the disease in all of them. As opposed to that, all 7 patients with the multicentric form of Castlemans disease experienced febrile or subfebrile temperatures. Three of the 7 patients complained of severe troubling night sweats. Clinical expressions of vasculitis which was the cause of stroke, were present in 1 of 7 patients. Osteosclerotic changes on the skeleton were detected in 1 patient, who also suffered from fluid retention likely associated with this disease. Polyclonal propagation of immunoglobulins, predominantly immunoglobulin IgG type, was present in 5 of 7 patients with the multicentric form. In one case there was one complete molecule of monoclonal imunoglobuline present and in one case loose light chains κ were increased More than 1 sampling of material for histological examination of enlarged lymph nodes were needed in 6 of 7 patients for diagnosing the multicentric form of the disease. It has turned out beneficial with respect to diagnosing the disease to carry out surgical removal and histological examination of the nodes which accumulated the most fluorodeoxyglucose within PET-CT examination. The text describes experience of the treatment. In recent years the basis for the treatment has been the monoclonal antibody antiCD20 rituximab, or thalidomide and lenalidomide, or possibly their combination. The new medicine for these patients is interleukin-6 antibody called siltuximab (Sylvant), of which we have no own experience so far. Five of our seven patients with the multicentric form received treatment, 1 patient refused treatment and in one patient the signs of the disease activity are not expressed to such extent that would require treatment. The therapy containing rituximab reached complete remission in 2 patients and the therapy containing thalidomide and lenalidomide achieved the complete remission of the disease in 3 patients. In one of the above described cases the disease did not respond to the initial treatment with rituximab and remission was reached by thalidomide and lenalidomide and in one case the disease did not respond to the initial treatment with thalidomide and complete remission was reached with rituximab. Following the treatment, no patient with the multicentric form of Castlemans disease has had a relapse until now.

[PET-CT documented remission of multicentric Castleman disease after treatment with rituximab: case report and review]. / PET-CT dokumentovaná remise multicentrické formy Castlemanovy choroby po lécbe rituximabem Popis prípadu a prehled literatury.

We describe a case of multicentric Castleman disease with generalized lymphadenopathy and splenomegaly, accompanied by typical B symptoms - loss of 15 kg, fever of non-infectious origin, night sweats, symptoms of anemia. Histological examination of the nodes with the highest accumulation of fluorodeoxyglucose, taken from mediastinum by thoracoscopy, revealed plasmocellular type of Castleman disease. Tests for HIV and human herpesvirus 8 (HHV-8) were negative. Three recurrences of herpes zoster indicating an alteration of immunity preceded the dia-gnosis of disease. Treatment was initiated with combination of thalidomide, dexamethasone, and cyclophosphamide. The response after 2 months therapy was not clear and patient doesn't tolerated the therapy well. Therefore, this treatment was terminated and R-CHOP (Mabthera - rituximab, cyclophosphamide, adriamycin, vincristine, and prednisone) was selected as a second-line therapy. Lymphadenopathy and splenomegaly were reduced during the 2 cycles of treatment, however, serious infectious complications accompanied the therapy. Therefore, only use of Mabthera monotherapy 375 mg /m2 was administered in 28-day intervals. This treatment has shown efficacy and tolerability. PET-CT scan has demonstrated disappearance of lymphadenopathy and splenomegaly, in addition, normalized accumulation of fluorodeoxyglucose. Monotherapy with Mabthera has proved to be effective and well tolerated drug in this case. Currently, there are more effective therapeutic alternatives in multicentric Castleman disease: treatment with monotherapy of rituximab or in combination therapy with immunomodulatory drugs (thalidomide or lenalidomide, treatment with anti-IL-6 (siltuximab) or against its receptor (tocilizumab). In the case of ineffectiveness of one treatment option must be tested other alternative. In this case the therapy based on thalidomide wasn't successful, whereas the treatment with Mabthera has achieved disappearance of disease symptoms.