Improvement of Docetaxel Efficacy through Simultaneous Blockade of Transcription Factors NF-κB and STAT-3 Using Pentoxifylline and Stattic in Prostate Cancer Cells.

Prostate cancer (PCa) is a common and deadly disease in men. It is often diagnosed at advanced stages, at which point patients are treated mainly with docetaxel (DTX), which is effective but limited by resistance and side effects. Overactivation of the transcription factors NF-κB and STAT-3 plays a critical role in the development, progression, and chemoresistance of PCa. In this regard, the blockade of NF-κB with pentoxifylline (PTX) or STAT-3 with Stattic (STT) is known to increase the sensitivity of tumor cells to chemotherapy in both in vitro and in vivo models. We investigated whether simultaneous blockade with PTX and STT increases the efficacy of the DTX treatment in inducing apoptosis in metastatic castration-resistant PCa DU-145 cells. Our results showed that the combination of PTX + STT led to higher levels of apoptosis, regardless of whether or not DTX was present in the treatment. Determining caspases and ΔΨm indicates that the intrinsic caspase pathway of apoptosis is principally favored. In addition, this combination inhibited proliferation and colony formation and arrested the cell cycle in the G1 phase. These results indicate that the combination of the PTX + STAT-3 inhibitor could potentiate DTX effectively, opening the possibility of effective treatments in PCa.

Pentoxifylline Inhibits TNF-α/TGF-ß1-Induced Epithelial-Mesenchymal Transition via Suppressing the NF-κB Pathway and SERPINE1 Expression in CaSki Cells.

Cervical cancer (CC) is one of the most common and deadly types of female cancer worldwide. Late diagnosis in CC increases the risk of tumor cells spreading to distant organs (metastasis). The epithelial-mesenchymal transition (EMT) is a fundamental process of cancer metastasis. Inflammation can lead to tumor progression, EMT induction, and metastasis. The inflammatory microenvironment is a potent inducer of EMT; inflammatory cytokines such as Tumor Necrosis Factor-alpha (TNF-α) and Transforming growth factor-beta (TGF-ß1) activate transcriptional factors such as STAT3, Snail, Smad, and the Nuclear Factor kappa light-chain-enhancer of activated beta cells (NF-κΒ), which drive EMT. Anti-inflammatory compounds may be an option in the disruption of EMT. PenToXifylline (PTX) possesses potent anti-inflammatory effects by inhibiting NF-κB activity. In addition, PTX exerts an anti-fibrotic effect by decreasing Smad2/3/4. We hypothesize that PTX could exert anti-EMT effects. CaSki human cervical tumor cells were exposed to TNF-α 10 ng/mL and TGF-ß1 alone or in combination for 5 days. Our results revealed that TNF-α and TGF-ß1 induced N-cadherin and Vimentin, confirming the induction of EMT. Furthermore, the combination of cytokines synergized the expression of mesenchymal proteins, enhanced IκBα and p65 phosphorylation, and upregulated Serpin family E member 1 (SERPINE1) mRNA. PTX pretreatment prior to the addition of TNF-α and TGF-ß1 significantly reduced N-cadherin and Vimentin levels. To our knowledge, this is the first time that this effect of PTX has been reported. Additionally, PTX reduced the phosphorylation of IκB-α and p65 and significantly decreased SERPINE1 expression, cell proliferation, migration, and invasion. In conclusion, PTX may counteract EMT in cervical cancer cells by decreasing the NF-κB and SERPINE1.

Metformin in combination with chemotherapy increases apoptosis in gastric cancer cells and counteracts senescence induced by chemotherapy.

Gastric cancer (GC) is the fourth leading cause of cancer death in the world, and there is a demand for new therapeutic agents to treat GC. Metformin has been demonstrated to be an antineoplastic agent in some types of cancer; however, it has not been sufficiently valued in treating GC because the effect of metformin in combination with chemotherapy regimens has not yet been evaluated. The present study aimed to evaluate the mechanisms underlying cell death induced by metformin alone or when combined with chemotherapy. The cytogenetic characteristics of the NCI-N87 cell line were determined by fluorescence in situ hybridization (FISH). To determine viability, the cells were treated with metformin, epirubicin, cisplatin, docetaxel and 5-fluorouracil (individually and at different concentrations). Subsequently, the cells were treated with metformin alone, and in combination with the chemotherapeutic drugs and the epirubicin + cisplatin + 5-fluorouracil, docetaxel + cisplatin + 5-fluorouracil, and cisplatin + 5-fluorouracil regimens. Cell viability, proliferation and mitochondrial membrane potential (ΔΨm) were analyzed by spectrophotometry. Apoptosis, caspase activity and cell cycle progression were assessed by flow cytometry. Finally, light microscopy was used to evaluate senescence and clonogenicity. The results revealed that metformin, alone and when combined with chemotherapy, increased the proportion of apoptotic cells, promoted the loss of ΔΨm, and induced apoptosis through caspase activity in GC cells. Moreover, metformin decreased cell proliferation. In addition, metformin alone did not induce senescence and it counteracted the effects of chemotherapy-induced senescence in GC cells. Additionally, metformin, alone and when combined with chemotherapy, decreased the clonogenic capacity of NCI-N87 GC cells. In conclusion, metformin may increase the effects of chemotherapy on NCI-N87 cell death and could represent an option to improve the treatment of GC.

Expression of ornithine decarboxylase in peripheral blood mononuclear cells from patients with pancreatic adenocarcinoma: A preliminary report.

Ductal adenocarcinoma represents 90-95% of pancreatic cancer (PC) cases and it is an aggressive disease with asymptomatic evolution at early stages, non-specific symptoms and a typical late diagnosis with a 5-year survival rate estimated to be 8%. A window of opportunity lies in early diagnosis as there are currently no reliable biomarkers. CA 19-9 is one of the most frequently used biomarkers of PC, with 75 and 77.6% sensitivity (Se) and specificity (Sp), respectively, and the carcinoembryonic antigen (CEA) shows 39.5 and 81.3% of Se and Sp, respectively. A case-control study was conducted including adult patients with a histological diagnosis of PC (n=11) without previous treatment at the Oncology Service of the CMNO-IMSS between 2019 and 2020, and a control group of adult volunteers (n=11) who were clinically healthy or with controlled disease including hypertension, hypothyroidism and diabetes. Clinical, laboratory and sociodemographic data as well as blood, urine and saliva samples were collected following patient consent. Polyamines were quantified using high-performance liquid chromatography with fluorescence detection, CA 19-9 and CEA were evaluated using enzyme-linked immunosorbent assay, and the protein expression of ornithine decarboxylase (ODC) was evaluated using western blotting. Polyamine metabolism and modulation by means of ODC were increased in the serum and saliva of patients with PC, and the expression of ODC alone was increased in peripheral blood mononuclear cells (PBMCs). The present study focused on the evaluation of putrescine, spermine, spermidine and ODC in PBMCs associated with CA 19-9 and CEA as an auxiliary tool in PC diagnosis.

FOXP3 Isoforms Expression in Cervical Cancer: Evidence about the Cancer-Related Properties of FOXP3Δ2Δ7 in Keratinocytes.

Cervical cancer (CC) is the fourth most common type of cancer among women; the main predisposing factor is persistent infection by high-risk human papillomavirus (hr-HPV), mainly the 16 or 18 genotypes. Both hr-HPVs are known to manipulate the cellular machinery and the immune system to favor cell transformation. FOXP3, a critical transcription factor involved in the biology of regulatory T cells, has been detected as highly expressed in the tumor cells of CC patients. However, its biological role in CC, particularly in the keratinocytes, remained unclarified. Therefore, this work aimed to uncover the effect of FOXP3 on the biology of the tumoral cells. First, public databases were analyzed to identify the FOXP3 expression levels and the transcribed isoforms in CC and normal tissue samples. The study's findings demonstrated an increased expression of FOXP3 in HPV16+ CC samples. Additionally, the FOXP3Δ2 variant was detected as the most frequent splicing isoform in tumoral cells, with a high differential expression level in metastatic samples. However, the analysis of FOXP3 expression in different CC cell lines, HPV+ and HPV-, suggests no relationship between the presence of HPV and FOXP3 expression. Since the variant FOXP3Δ2Δ7 was found highly expressed in the HPV16+ SiHa cell line, a model with constitutive expression of FOXP3Δ2Δ7 was established to evaluate its role in proliferation, migration, and cell division. Finally, RNAseq was performed to identify differentially expressed genes and enriched pathways modulated by FOXP3Δ2Δ7. The exogenous expression of FOXP3Δ2Δ7 promotes cell division, proliferation, and migration. The transcriptomic analyses highlight the upregulation of multiple genes with protumor activities. Moreover, immunological and oncogenic pathways were detected as highly enriched. These data support the hypothesis that FOXP3Δ2Δ7 in epithelial cells induces cancer-related hallmarks and provides information about the molecular events triggered by this isoform, which could be important for developing CC.