Cyclin-dependent kinase (CDK)-7 inhibitors are emerging as promising drugs for the treatment of different types of cancer that show chemotherapy resistance. Evaluation of the effects of CDK7 inhibitor, THZ1, alone and combined with tamoxifen is of paramount importance. Thus, in the current work, we assessed the effects of THZ1 and/or tamoxifen in two estrogen receptor-positive (ER+) breast cancer cell lines (MCF7) and its tamoxifen resistant counterpart (LCC2) in vitro and in xenograft mouse models of breast cancer. Furthermore, we evaluated the expression of CDK7 in clinical samples from breast cancer patients. Cell viability, apoptosis, and genes involved in cell cycle regulation and tamoxifen resistance were determined. Tumor volume and weight, proliferation marker (Ki67), angiogenic marker (CD31), and apoptotic markers were assayed. Bioinformatic data indicated CDK7 expression was associated with negative prognosis, enhanced pro-oncogenic pathways, and decreased response to tamoxifen. Treatment with THZ1 enhanced tamoxifen-induced cytotoxicity, while it inhibited genes involved in tumor progression in MCF-7 and LCC2 cells. In vivo, THZ1 boosted the effect of tamoxifen on tumor weight and tumor volume, reduced Ki67 and CD31 expression, and increased apoptotic cell death. Our findings identify CDK7 as a possible therapeutic target for breast cancer whether it is sensitive or resistant to tamoxifen therapy.

Reusing food waste is becoming popular in pharmaceutical industries. Watermelon (Citrullus lanatus) rind is commonly discarded as a major solid waste. Here, the in vitro cytotoxic potential of watermelon rind extracts was screened against a panel of human cancer cell lines. Cell cycle analysis was used to determine the induction of cell death, whereas annexin V-FITC binding, caspase-3, BAX, and BCL-2 mRNA expression levels were used to determine the degree of apoptosis. VEGF-promoting angiogenesis and cell migration were also evaluated. Moreover, the identification of phytoconstituents in the rind extract was achieved using UPLC/T-TOF-MS/MS, and a total of 45 bioactive compounds were detected, including phenolic acids, flavonoids aglycones, and their glycoside derivatives. The tested watermelon rind extracts suppressed cell proliferation in seven cancer cell lines in a concentration-dependent manner. The cytotoxicity of the rind aqueous extract (RAE) was higher compared with that of the other extracts. In addition to a substantial inhibitory effect on cell migration, the RAE triggered apoptosis in HCT116 and Hep2 cells by driving the accumulation of cells in the S phase and elevating the activity of caspase-3 and the BAX/BCL-2 ratio. Thus, a complete phytochemical and cytotoxic investigation of the Citrullus lanatus rind extract may identify its potential potency as an anticancer agent.

Hepatocellular carcinoma (HCC) is characterized by its high vascularity and metastasis. Thymoquinone (TQ), the main bio-active constituent of Nigella sativa, has shown anticancer and hepatoprotective effects. TQ’s anticancer effect is mediated through miRNA regulation. miR-1-3p plays a significant role in various cancers but its role in HCC invasiveness remains poorly understood. Bio-informatics analysis predicted that the 3′-UTR of TIMP3 is a target for miR-1-3p; Rats were equally divided into four groups: Group 1, the negative control; Group 2 received TQ; Group 3 received DEN; and Group 4 received DEN after pretreatment with TQ. The expression of TIMP3, MMP2, MMP9, and VEGF in rats’ liver was determined immunohistochemically. RT-qPCR was used to measure the miR-1-3p level in rats’ liver, and TIMP3, MMP2, MMP9, and VEGF in the HepG2 cells after being transfected with miR-1-3p mimic or inhibitor; In rats pretreated with TQ, a decreased expression of MMP2, MMP9 and VEGF, and increased expression levels of TIMP3 and miR-1-3p were detected. Treating the HepG2 cells with miR-1-3p mimic led to the upregulation of TIMP3 and downregulation of MMP2, MMP9, and VEGF, and showed a significant delay in wound healing; These results suggested that the anti-angiogenic effect of TQ in HCC may be mediated through the regulation of miR-1-3p.

Colorectal cancer (CRC) remains one of the leading causes of cancer mortality, with a poor survival rate of less than 15%. Imatinib (IM) and Zebularine (ZEB) alone have shown potential effects in CRC treatment, but their combination has not been thoroughly studied. This study investigates the potential effects of IM and ZEB in colon cancer cells to provide a novel therapeutic agent for managing CRC. Cell growth inhibition, oxidative stress markers, and cell cycle progression were assessed in HCT‐116 cells treated with IM, ZEB, and their combinations. ZEB uptake levels were analyzed by LC‐MS/MS, apoptosis was quantified by flow cytometry, and gene expression changes were analyzed by qPCR. The expression of metastatic markers, apoptotic regulators, and EGFR was assessed. Both IM and ZEB inhibited cell growth in a concentration‐dependent manner, and their combination showed synergistic effects. The combination significantly enhanced oxidative stress. The combination therapy increased apoptosis and necrosis. Furthermore, the combination induced significant S‐phase arrest in the cell cycle. The combination treatment reduced metastatic markers (MMP9, MMP2), and the apoptotic marker Caspase‐9 was upregulated. Additionally, the Bcl‐2 protein, a key regulator of apoptosis, was significantly downexpressed. Remarkably, the combination treatment showed significant inhibition in EGFR levels. Both IM and ZEB combination showed promise in the management of CRC by inducing oxidative stress, promoting apoptosis, and modulating critical genes involved in metastasis and apoptosis. Further investigation will be needed to verify their application in preclinical and clinical settings.

A novel ruthenium(III)-pyrimidine Schiff base was synthesized and characterized using different analytical and spectroscopic techniques. Molecular geometries of the ligand and ruthenium complex were investigated using the DFT-B3LYP level of theory. The quantum global reactivity descriptors were also calculated. Various biological and molecular docking studies of the complex are reported to explore its potential application as therapeutic drug. Cytotoxicity of the complex was screened against cancer colorectal (HCT116), breast (MCF-7 and T47D), hepatocellular (HepG2) cell lines as well as human normal cell line (HSF). The complex effectively inhibited the tested cancer cells with variable degree with higher activity towards HepG2. The complex induced apoptosis and cell cycle arrest in the S phase of HepG2 cells. The complex significantly induced the expression of H2AX, and caspase 3 and caspase 7 gene and protein level of caspase 3 as well as inhibited VEGF-A, and mTOR /AKT, SND1, NFkB gene expression. The molecular docking studies supported the increased the total apoptosis of treated HepG2 cells due to strong interaction of the complex with DNA. Also, the possible binding interaction of the complex with caspase 3 could be responsible for the elevated activity of caspase 3 treated cells.