Multifunctional PAMAM Dendrimers Carrying SAHA, 5-FU, and a Therapeutic Gene for Targeted Co-Delivery Toward Colorectal Cancer Cells.

A promising approach to treat colorectal cancer (CRC) involves combining chemotherapy, epigenetics, and gene therapy to combat drug resistance. Multifunctional nanocarriers have emerged as a valuable tool for targeted CRC therapy. By delivering multiple treatments directly to cancer cells, these nanocarriers offer the potential for improved outcomes and reduced side effects.

Mouse models for cancer research - current state and the perspective.

Cancer is one of the leading causes of death worldwide. We still do not understand all the details of carcinogenesis, and effective treatment is lacking for many oncological diseases. Animal models provide an irreplaceable tool to observe the growth and spreading of neoplastic cells in an environment of living organisms, to test the efficacy of cancer treatment, side effects, and toxicity, and to study the tumor microenvironment.

Overexpression of TNFα induces senescence, autophagy and mitochondrial dysfunctions in melanoma cells.

Background: Tumor necrosis factor alpha (TNFα) is a pleiotropic cytokine with both anti-tumorigenic and pro-tumorigenic activity, affecting tumor cell biology, the balance between cell survival and death. The final effect of TNFα is dependent on the type of malignant cells, with the potential to arrest cancer progression.

Methods: In order to explain the diverse cellular response to TNFα, we engineered melanoma and colorectal carcinoma cell lines stably overexpressing this cytokine.

Silencing of carbonic anhydrase I enhances the malignant potential of exosomes secreted by prostatic tumour cells.

We report results showing that the silencing of carbonic anhydrase I (siCA1) in prostatic (PC3) tumour cells has a significant impact on exosome formation. An increased diameter, concentration and diversity of the produced exosomes were noticed as a consequence of this knock-down. The protein composition of the exosomes' cargo was also altered.

Cytotoxic response of 5-fluorouracil-resistant cells to gene- and cell-directed enzyme/prodrug treatment.

Gene-directed enzyme/prodrug therapy (GDEPT) mediated by mesenchymal stromal cells (MSC) was already approved for clinical study on a progressive disease refractory to standard therapy. In this work, we examined the effect of several GDEPT approaches on chemoresistant cells. First, we derived 5-fluorouracil (5-FU)-resistant variant of human colorectal adenocarcinoma cells HT-29 designated HT-29/EGFP/FUR.

Silencing of CA1 mRNA in tumour cells does not change the gene expression of the extracellular matrix proteins.

We report the silencing of CA1 mRNA in PC3 and MDA cells. The levels of mRNA coding CA1 protein in the knock-down mRNA (CA1 siRNA) cells have been measured by RT-PCR and were approximately 5% (PC3) and 20% (MDA-MB-231), respectively, of the level of control (Mock siRNA) used during silencing. In PC3 and MDA-MB-231 cells, the mRNAs for COL1A1 and COL4A4 were up-regulated.

Sera of patients with spontaneous tumour regression and elevated anti-CA I autoantibodies change the gene expression of ECM proteins.

Spontaneous tumour regression after high-dose therapy and autologous stem cell transplantation is associated with the aplastic anaemia-like syndrome and the presence of polyclonal autoantibodies against carbonic anhydrase I (CA I). When tumour cells were grown in vitro in the presence of patients' sera positive for anti-CA I autoantibodies, their morphological pattern was altered. These changes were accompanied by modifications in the gene expression profile.

Cisplatin-induced mesenchymal stromal cells-mediated mechanism contributing to decreased antitumor effect in breast cancer cells.

Background: Cells of the tumor microenvironment are recognized as important determinants of the tumor biology. The adjacent non-malignant cells can regulate drug responses of the cancer cells by secreted paracrine factors and direct interactions with tumor cells.

Results: Human mesenchymal stromal cells (MSC) actively contribute to tumor microenvironment.

Combined enzyme/prodrug treatment by genetically engineered AT-MSC exerts synergy and inhibits growth of MDA-MB-231 induced lung metastases.

Background: Metastatic spread of tumor cells remains a serious problem in cancer treatment. Gene-directed enzyme/prodrug therapy mediated by tumor-homing genetically engineered mesenchymal stromal cells (MSC) represents a promising therapeutic modality for elimination of disseminated cells. Efficacy of gene-directed enzyme/prodrug therapy can be improved by combination of individual systems.

Genetically engineered mesenchymal stromal cells producing TNFα have tumour suppressing effect on human melanoma xenograft.

Background: Mesenchymal stromal cells (MSC) are a promising tool for targeted cancer therapy due to their tumour-homing ability. Intrinsic resistance enables the MSC to longer tolerate therapeutic factors, such as prodrug converting enzymes, cytokines and pro-apoptotic proteins. Tumour necrosis factor alpha (TNFα) is known to be cytotoxic to a variety of cancer cells and exert a tumour-destructive capacity.

Increased proliferation and chemosensitivity of human mesenchymal stromal cells expressing fusion yeast cytosine deaminase.

Mesenchymal stromal cells (MSCs) are considered to be suitable vehicles for cellular therapy in various conditions. The expression of reporter and/or effector protein(s) enabled both the identification of MSCs within the organism and the exploitation in targeted tumor therapies. The aim of this study was to evaluate cellular changes induced by retrovirus-mediated transgene expression in MSCs in vitro.

Cytosine deaminase expressing human mesenchymal stem cells mediated tumour regression in melanoma bearing mice.

Background: Previously, we validated capability of human adipose tissue-derived mesenchymal stem cells (AT-MSC) to serve as cellular vehicles for gene-directed enzyme prodrug molecular chemotherapy. Yeast fusion cytosine deaminase : uracil phosphoribosyltransferase expressing AT-MSC (CD y-AT-MSC) combined with systemic 5-fluorocytosine (5FC) significantly inhibited growth of human colon cancer xenografts. We aimed to determine the cytotoxic efficiency to other tumour cells both in vitro and in vivo.

The KlPGS1 gene encoding phosphatidylglycerolphosphate synthase in Kluyveromyces lactis is essential and assigned to chromosome I.

The phosphatidylglycerolphosphate synthase (CDP-diacylglycerol:sn-glycerol-3-phosphate 3-phosphatidyltransferase, EC 2.7.8.