Venkateshwar Madka

Bladder cancer (BCa) is the second most common cancer of the genitourinary tract globally. It has limited treatment options, high recurrence rate, and acquires resistance to platinum-based therapy. Therefore, identifying novel therapeutic targets is urgently needed. Analysis of the TCGA data revealed that the enzyme galactokinase-1 (GALK1) is overexpressed (p < 0.0001) in bladder tumors compared to normal tissue. Our data also confirmed GALK1 protein upregulation in multiple human BCa cell lines and rodent bladder tumors. However, the precise role of GALK1 in BCa progression and effects of its specific inhibitor remain unexamined. In this study, we demonstrate that GALK1 gene silencing using shRNA resulted in a significant reduction in BCa cell proliferation, migration, and invasion. Pharmacological inhibition of GALK1 using small molecule Cpd36 resulted in anticancer efficacy against BCa. Cpd36 inhibited proliferation, migration, and invasion of BCa cells. Further, Cpd36 induced G1 phase cell cycle arrest, apoptosis, mitochondrial membrane depolarization, and ROS production in the BCa cells. Mechanistically, Cpd36-induced reduction in cell proliferation was associated with a decrease in expression of GALK1, PCNA proteins. Inhibition of metastatic potential was accompanied by decreased migration, invasion, and MMP-9 expression. Cell cycle arrest was associated with decrease in Cyclin D1 and increased expression of p21 and p27. Induction of apoptosis was linked with increased expression of cleaved caspase-3 and cleaved PARP, while downregulating p-AKT. Additionally, Cpd36 in combination with cisplatin or gemcitabine showed a strong synergistic effect on BCa cells. Taken together, our findings suggest that GALK1 plays a significant role in BCa cell survival and validates its inhibitors as promising therapeutic options for managing this disease.

Cancer initiation and progression are associated with numerous somatic mutations, genomic rearrangements, and structure variants. The transformation of a normal cell into a cancer cell involves spatio-temporal changes in the regulation of different gene networks. The accessibility of these genes within the cell nucleus is manipulated via nucleosome remodeling ATPases, comprising one of the important mechanisms. Here, we reviewed studies of an ATP-dependent chromatin remodulator, chromodomain helicase DNA-binding 4 (CHD4), in cancer. Multiple domains of CHD4 are known to take part in nucleosome mobilization and histone binding. By binding with other proteins, CHD4 plays a vital role in transcriptional reprogramming and functions as a key component of Nucleosome Remodeling and Deacetylase, or NuRD, complexes. Here, we revisit data that demonstrate the role of CHD4 in cancer progression, tumor cell proliferation, DNA damage responses, and immune modulation. Conclusively, CHD4-mediated chromatin accessibility is essential for transcriptional reprogramming, which in turn is associated with tumor cell proliferation and cancer development.

Colorectal cancer (CRC) is one of the major reasons for cancer-related deaths around the world. Constitutive activation of WNT pathway, due to APC gene mutation, is the characteristic feature of most human colon tumors. Familial adenomatous polyposis (FAP) patients inherit APC mutations and pose an absolute risk of developing CRC in their lifetime. The genetically modified APC mouse models have paved the way to study various aspects of the hereditary human CRC, including biochemical, molecular, and histological aspects. Preclinical and clinical data suggest that certain dietary supplements, NSAIDs, natural products, and chemically synthesized compounds, can help in intercepting CRC incidence and progression by modulating various hallmarks of cancer. In this review, we have provided a summary of promising natural and synthetic agents that demonstrated chemopreventive efficacy against CRC in the FAP-mimicking APC^Min/+ mouse model.

TRIP13 is a member of the large AAA+ ATPase protein superfamily that plays a crucial role in the precise segregation of chromosomes during mitosis. The abnormal function of TRIP13 has diverse functions, including mitotic processes, DNA repair pathways, and spindle assembly checkpoints, which may contribute to chromosomal instability (CIN). Emerging evidence suggests that the overexpression of TRIP13, observed in many cancers, plays a significant role in drug resistance, autophagy, and immune invasion. Recently, significant advances have been made in identifying TRIP13-associated signaling pathways that have been implicated in cancer progression. Several small molecules that specifically inhibit TRIP13 function and reduce cancer cell growth have been developed. Combination treatments, including TRIP13 inhibitors and other anticancer drugs, have shown promising results. While these findings are promising, TRIP13 inhibitors are awaiting clinical trials. This review discusses recent progress in understanding the oncogenic function of TRIP13 and its possible therapeutic targets, which could be exploited as an attractive option for cancer management.

Bladder cancer (BCa) is one of the most lethal genitourinary malignancies owing to its propensity for recurrence and poor survival. The biochemical pathway, signal transducer and activator of transcription 3 (STAT3), has gained significance as a molecular pathway that promotes proliferation, invasion, and chemoresistance. In this study, we explored the targeting of STAT3 with TTI-101 and SH5-07 in BCa and elucidated the mechanisms in three-dimensional (3D) spheroid and organoid models. We optimized the growth of spheroids from human, rat, and mouse BCa cell lines (J82, NBT-II, and MB49 respectively) and organoids from BBN (N-butyl-N-(4-hydroxybutyl)-nitrosamine)-induced rat bladder tumors. Cell viability was assessed using MTT and trypan blue assays. Intracellular ATP production, ROS production, and calcium AM (CA)/EtBr staining were used to measure the spheroid and organoid inhibition and mitochondrial function. Western blot analysis was performed to evaluate the pharmacodynamic markers involved in cell proliferation, apoptosis, cancer stem cells (CSCs), and STAT3 signaling in BCa. We found that targeting STAT3 (using TTI-101 and SH5-07) significantly reduced the proliferation of BCa spheroids and organoids, which was accompanied by decreased expression of pSTAT3, Cyclin D1, and PCNA. Our data also demonstrated that treatment with STAT3 inhibitors induced ROS production and cell death in BCa spheroids and organoids. STAT3 inhibition-induced cell death was associated with the activation of caspase 3/7 and PARP cleavage. Moreover, TTI-101 and SH5-07 target cancer stem cells by downregulating the expression of CD44 and CD133 in 3D models. This study provides the first evidence for the prevention of BCa with small-molecule inhibitors TTI-101 and SH5-07 via suppression of CSCs and STAT3 signaling.

Bladder cancer (BC) is one of the most lethal genitourinary malignancies owing to its propensity for recurrence and poor survival. The biochemical pathway, signal transducer and activator of transcription 3 (STAT3), has gained significance as a molecular pathway that promotes proliferation, invasion, and chemoresistance. In this study, we explored the targeting of STAT3 with TTI-101 and SH5-07 in bladder cancer (BCa) and elucidated the mechanisms in three-dimensional (3D) spheroid and tumoroid models. We optimized the growth of spheroids from human, rat, and mouse BCa cell lines (J82, NBT-II, and MB49, respectively), and tumoroids from BBN (N-butyl-N-(4-hydroxybutyl)-nitrosamine) induced rat bladder tumors. Cell viability was assessed using MTT and trypan blue assays. ATP production, ROS production, and calcium AM (CA)/EtBr staining were used to measure the spheroid and organoid inhibition and mitochondrial function. Western blot analysis was performed to evaluate the pharmacodynamic markers involved in cell proliferation, apoptosis, cancer stem cells (CSCs), and STAT3 signaling in BCa. We found that targeting STAT3 (using TTI-101 and SH5-07) significantly reduced the proliferation of BCa spheroids, and tumoroids, which was accompanied by decreased expression of pSTAT3, Cyclin D1, and PCNA. Our data also demonstrated that treatment with STAT3 inhibitors induced ROS production and cell death in BCa spheroids and organoids. STAT3 inhibition induced cell death was associated with the activation of caspase 3/7 and PARP cleavage. Moreover, TTI-101 and SH5-07 targets cancer stem cells by downregulating the expression of CD44 and CD133 in 3D models. This study provides the first evidence for the prevention of bladder cancer with small-molecule inhibitors TTI101 and SH5-07 via suppression of CSCs and STAT3 signaling.