Click Pt(IV)-Carbohydrates Pro-Drugs for Treatment of Osteosarcoma

The selectivity vs. cancer cells has always been a major challenge for chemotherapeutic agents and in particular for cisplatin, one of the most important anticancer drugs for the treatment of several types of tumors. One strategy to overtake this challenge is to modify the coordination sphere of the metallic center with specific vectors whose receptors are overexpressed in the tumoral cell membrane, such as monosaccharides. In this paper, we report the synthesis of four novel glyco-modified Pt(IV) pro-drugs, based on cisplatin scaffold, and their biological activity against osteosarcoma (OS), a malignant tumor affecting in particular adolescents and young adults. The sugar moiety and the Pt scaffold are linked exploiting the Copper Azide Alkyne Cycloaddition (CUAAC) reaction, which has become the flagship of click chemistry due to its versatility and mild conditions. Cytotoxicity and drug uptake on three different OS cell lines as well as CSCs (Cancer Stem Cell) are described.

Single-cell mtDNA heteroplasmy in colorectal cancer

Human mitochondria can be genetically distinct within the same individual, a phenomenon known as heteroplasmy. In cancer, this phenomenon seems exacerbated, and most mitochondrial mutations seem to be heteroplasmic. How this genetic variation is arranged within and among normal and tumor cells is not well understood. To address this question, here we sequenced single-cell mitochondrial genomes from multiple normal and tumoral locations in four colorectal cancer patients. Our results suggest that single cells, both normal and tumoral, can carry various mitochondrial haplotypes. Remarkably, this intra-cell heteroplasmy can arise before tumor development and be maintained afterward in specific tumoral cell subpopulations. At least in the colorectal patients studied here, the somatic mutations in the single-cells do not seem to have a prominent role in tumorigenesis.

A Preclinical Pipeline for Translational Precision Medicine—Experiences from a Transdisciplinary Brain Tumor Stem Cell Project

Efficient transdisciplinary cooperation promotes the rapid discovery and clinical application of new technologies, especially in the competitive sector of oncology. In this review, written from a clinical-scientist point of view, we used glioblastoma—the most common and most aggressive primary brain tumor as a model disease with a largely unmet clinical need, despite decades of intensive research—to promote transdisciplinary medicine. Glioblastoma stem-like cells (GSCs), a special tumoral cell population analogue to healthy stem cells, are considered largely responsible for the progression of the disease and the mediation of therapy resistance. The presented work followed the concept of translational science, which generates the theoretical backbones of translational research projects, and aimed to close the preclinical gap between basic research and clinical application. Thus, this generated an integrated translational precision medicine pipeline model based on recent theoretical and experimental publications, which supports the accelerated discovery and development of new paths in the treatment of GSCs. The work may be of interest to the general field of precision medicine beyond the field of neuro-oncology such as in Cancer Neuroscience.

Fucoxanthin Holds Potential to Become a Drug Adjuvant in Breast Cancer Treatment: Evidence from 2D and 3D Cell Cultures

Fucoxanthin (Fx) is a carotenoid derived from marine organisms that exhibits anticancer activities. However, its role as a potential drug adjuvant in breast cancer (BC) treatment is still poorly explored. Firstly, this study investigated the cytotoxic effects of Fx alone and combined with doxorubicin (Dox) and cisplatin (Cis) on a panel of 2D-cultured BC cell lines (MCF7, SKBR3 and MDA-MB-231) and one non-tumoral cell line (MCF12A). Fucoxanthin induced cytotoxicity against all the cell lines and potentiated Dox cytotoxic effects towards the SKBR3 and MDA-MB-231 cells. The combination triggering the highest cytotoxicity (Fx 10 µM + Dox 1 µM in MDA-MB-231) additionally showed significant induction of cell death and genotoxic effects, relative to control. In sequence, the same combination was tested on 3D cultures using a multi-endpoint approach involving bioactivity assays and microscopy techniques. Similar to 2D cultures, the combination of Fx and Dox showed higher cytotoxic effects on 3D cultures compared to the isolated compounds. Furthermore, this combination increased the number of apoptotic cells, decreased cell proliferation, and caused structural and ultrastructural damages on the 3D models. Overall, our findings suggest Fx has potential to become an adjuvant for Dox chemotherapy regimens in BC treatment.

Repurposing ketoconazole as an exosome directed adjunct to sunitinib in treating renal cell carcinoma

Renal Cell Carcinoma (RCC) is the most common form of kidney cancer, with clear cell RCC (ccRCC) representing about 85% of all RCC tumors. There are limited curable treatments available for metastatic ccRCC because this disease is unresponsive to conventional targeted systemic pharmacotherapy. Exosomes (Exo) are small extracellular vesicles (EVs) secreted from cancer cells with marked roles in tumoral signaling and pharmacological resistance. Ketoconazole (KTZ) is an FDA approved anti-fungal medication which has been shown to suppress exosome biogenesis and secretion, yet its role in ccRCC has not been identified. A time-course, dose-dependent analysis revealed that KTZ selectively decreased secreted Exo in tumoral cell lines. Augmented Exo secretion was further evident by decreased expression of Exo biogenesis (Alix and nSMase) and secretion (Rab27a) markers. Interestingly, KTZ-mediated inhibition of Exo biogenesis was coupled with inhibition of ERK1/2 activation. Next, selective inhibitors were employed and showed ERK signaling had a direct role in mediating KTZ’s inhibition of exosomes. In sunitinib resistant 786-O cells lines, the addition of KTZ potentiates the efficacy of sunitinib by causing Exo inhibition, decreased tumor proliferation, and diminished clonogenic ability of RCC cells. Our findings suggest that KTZ should be explored as an adjunct to current RCC therapies.

Hybrid Cyclobutane/Proline-Containing Peptidomimetics: The Conformational Constraint Influences Their Cell-Penetration Ability

A new family of hybrid β,γ-peptidomimetics consisting of a repetitive unit formed by a chiral cyclobutane-containing trans-β-amino acid plus a Nα-functionalized trans-γ-amino-l-proline joined in alternation were synthesized and evaluated as cell penetrating peptides (CPP). They lack toxicity on the human tumoral cell line HeLa, with an almost negligible cell uptake. The dodecapeptide showed a substantial microbicidal activity on Leishmania parasites at 50 µM but with a modest intracellular accumulation. Their previously published γ,γ-homologues, with a cyclobutane γ-amino acid, showed a well-defined secondary structure with an average inter-guanidinium distance of 8–10 Å, a higher leishmanicidal activity as well as a significant intracellular accumulation. The presence of a very rigid cyclobutane β-amino acid in the peptide backbone precludes the acquisition of a defined conformation suitable for their cell uptake ability. Our results unveiled the preorganized charge-display as a relevant parameter, additional to the separation among the charged groups as previously described. The data herein reinforce the relevance of these descriptors in the design of CPPs with improved properties.

Effect of Isolated Serum from Breast Cancer Patients with Pectoral Nerves Block on Breast Cancer Cell Line (MDA-MB-231) Apoptosis Index

Background: Breast cancer (BC) is the most frequent cause of cancer death in women. The thoracic pectoral nerve (PECS) block has been described as the gold standard analgesic modality for BC surgery. It has been previously reported that PECS is associated with decreased BC recurrence post-mastectomy. Although several anesthetic drugs and techniques are used in surgical oncology, their effects on the behavior of cancer cells are yet to be known and the key question of whether the anesthetic technique affects cancer outcome remains unresolved. Objectives: Since anesthetic drugs and techniques and post-operative pain may affect BC recurrence, this study aimed to determine whether the anesthetic choice and technique, PECS II block, affects in vitro apoptosis of the MDA-MB-231 BC cell line. Methods: Twenty-two female BC patients, 20 to 75-years-old, with the same pathologic grades were included in this study. The patients were randomly divided into two groups. The first group received propofol general anesthesia (PGA) associated with PECS and the second group received standard PGA. Blood was sampled pre and post-operation from all patients. The sera were isolated and then exposed to the MDA-MB-231 human BC cell line. The mean percentage of apoptosis indices was analyzed by flow cytometry using Annexin V-fluorescein isothiocyanate 24 hours after treatment with patients’ sera. Results: A significant decrease was seen in the mean viability percentage of BC cell line in the PECS group, besides a significant increase in the mean percentage of necrosis and late apoptosis indices compared to the control group after exposure to sera collected from patients post-operation. Intra-group analysis of the control group showed that the exposure of the tumoral cell to post-operation sera resulted in a significant increase in the mean percentage of necrosis and late apoptosis index compared to pre-operation sera exposure. In the PECS group, the exposure of the tumoral cell to post-operation sera resulted in a significant increase in the mean percentage of cell viability and late apoptosis index compared to pre-operation sera exposure. Conclusions: In conclusion, anesthesia and BC surgery may induce apoptosis indices in the MDA-MB-231 human BC cell line. We also found that sera collected from PECS II block patients with BC could induce more apoptosis in the MDA-MB-231 cell line compared to collected sera from systemic analgesia alone after BC surgery.

Hepatic Arterial Buffer Response in Liver Radioembolization and Potential Use for Improved Cancer Therapy

Liver radioembolization is a treatment option for unresectable liver cancers, performed by infusion of 90Y or 166Ho loaded spheres in the hepatic artery. As tumoral cells are mainly perfused via the liver artery unlike hepatic lobules, a twofold tumor to normal liver dose ratio is commonly obtained. To improve tumoral cell killing while preserving lobules, co-infusion of arterial vasoconstrictor has been proposed but with limited success: the hepatic arterial buffer response (HABR) and hepatic vascular escape mechanism hamper the arterioles vasoconstriction. The proposed project aims to take benefit from the HABR by co-infusing a mesenteric arterial vasodilator: the portal flow enhancement inducing the vasoconstriction of the intra sinusoids arterioles barely impacts liver tumors that are mainly fed by novel and anarchic external arterioles. Animal studies were reviewed and dopexamine was identified as a promising safe candidate, reducing by four the hepatic lobules arterial flow. A clinical trial design is proposed. A four to sixfold improvement of the tumoral to normal tissue dose ratio is expected, pushing the therapy towards a real curative intention, especially in HCC where ultra-selective spheres delivery is often not possible.

In Search of Outliers. Mining for Protein Kinase Inhibitors Based on Their Anti-Proliferative NCI-60 Cell Lines Profile

Protein kinases play a pivotal role in signal transduction, protein synthesis, cell growth and proliferation. Their deregulation represents the basis of pathogenesis for numerous diseases such as cancer and pathologies with cardiovascular, nervous and inflammatory components. Protein kinases are an important target in the pharmaceutical industry, with 48 protein kinase inhibitors (PKI) already approved on the market as treatments for different afflictions including several types of cancer. The present work focuses on facilitating the identification of new PKIs with antitumoral potential through the use of data-mining and basic statistics. The National Cancer Institute (NCI) granted access to the results of numerous previously tested compounds on 60 tumoral cell lines (NCI-60 panel). Our approach involved analyzing the NCI database to identify compounds that presented similar growth inhibition (GI) profiles to that of existing PKIs, but different from approved oncologic drugs with other mechanisms of action, using descriptive statistics and statistical outliers. Starting from 34,000 compounds present in the database, we filtered 400 which displayed selective inhibition on certain cancer cell lines similar to that of several already-approved PKIs.