Targeting c-Met in the treatment of urologic neoplasms: Current status and challenges

Deciphering molecular pathways in urological cancers: a gateway to precision therapeutics

BACKGROUND

Urological cancers, including prostate, kidney, bladder, testicular, and penile cancers, pose a significant health challenge, particularly in their metastatic stages. Surgical interventions remain fundamental, but recent advancements in medical therapies like chemotherapy, immunotherapy, and targeted therapies have shown promise in improving patient outcomes.

AIM OF REVIEW

This review aims to explore the current landscape of targeted therapies in urological cancers, focusing on the role of key signaling pathways such as phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), mechanistic (mammalian) target of rapamycin (mTOR), growth factor-related mechanisms, c-Mesenchymal-epithelial transition factor (c-Met)/ hepatocyte growth factor (HGF), programmed cell death protein 1 and its ligand programmed death-ligand 1 (PD-1/PD-L1), and steroid hormone receptor pathways in tumor progression and therapeutic resistance. Key scientific concepts of review Dysregulation of pathways like PI3K/Akt and mTOR contributes to tumorigenesis, metastasis, and resistance to treatment, underscoring their relevance as therapeutic targets. Tyrosine kinase inhibitors and immune checkpoint inhibitors have demonstrated efficacy but face challenges such as intrinsic resistance and treatment-related toxicities. Integrating insights from signaling pathway research with clinical practice holds potential for developing more effective treatment paradigms, enhancing the efficacy of targeted therapies, and improving survival rates for patients with urological cancers.

From infection to tumor: genetic evidence of viral antibody immune response' role in urologic cancer development

BACKGROUND

Urologic tumors are among the most common malignancies worldwide, and the association between chronic infections and the risk of developing these tumors has garnered significant attention. However, traditional observational studies are prone to confounding factors, making it challenging to establish a clear causal relationship.

METHOD

This study employs a two-sample bidirectional Mendelian randomization analysis, utilizing genetic data on antibody levels and urologic tumors obtained from GWAS databases. The inverse variance weighted (IVW) method was used to estimate causal relationships, while MR-Egger and MR-PRESSO methods were applied for sensitivity analyses to assess horizontal pleiotropy and heterogeneity.

RESULT

The results showed that antibody levels associated with various viral infections were significantly correlated with the risk of developing urologic tumors. For example, antibodies related to cytomegalovirus IgG and Epstein-Barr virus (EBV) were found to have complex associations with the risk of prostate cancer, bladder cancer, and testicular cancer. Some antibodies, such as those related to Varicella zoster virus, were associated with a reduced risk of clear cell renal carcinoma. Additionally, sensitivity analyses suggested the potential presence of horizontal pleiotropy in bladder and testicular cancers.

CONCLUSION

Through Mendelian randomization analysis, we revealed a potential causal relationship between antibody immune responses and urologic tumors. These findings provide new evidence for the role of chronic infections in the pathogenesis of urologic tumors, suggesting that prevention and treatment strategies targeting related pathogens, such as vaccination and antiviral therapies, could offer new avenues for the prevention and management of urologic cancers.

Molecular mechanisms and targeted therapy for the metastasis of prostate cancer to the bones (Review)

The incidence of prostate cancer (PCa) is increasing, making it one of the prevalent malignancies among men. Metastasis of PCa to the bones poses the greatest danger to patients, potentially resulting in treatment ineffectiveness and mortality. At present, the management of patients with bone metastasis focuses primarily on providing palliative care. Research has indicated that the spread of PCa to the bones occurs through the participation of numerous molecules and their respective pathways. Gaining knowledge regarding the molecular processes involved in bone metastasis may result in the development of innovative and well‑tolerated therapies, ultimately enhancing the quality of life and prognosis of patients. The present article provides the latest overview of the molecular mechanisms involved in the formation of bone metastatic tumors from PCa. Additionally, the clinical outcomes of targeted drug therapies for bone metastasis are thoroughly analyzed. Finally, the benefits and difficulties of targeted therapy for bone metastasis of PCa are discussed, aiming to offer fresh perspectives for treatment.

Mechanisms of sensitivity and resistance to CDK4/CDK6 inhibitors in hormone receptor-positive breast cancer treatment

Cell cycle dysregulation is a hallmark of cancer that promotes eccessive cell division. Cyclin-dependent kinase 4 (CDK4) and cyclin-dependent kinase 6 (CDK6) are key molecules in the G1-to-S phase cell cycle transition and are crucial for the onset, survival, and progression of breast cancer (BC). Small-molecule CDK4/CDK6 inhibitors (CDK4/6i) block phosphorylation of tumor suppressor Rb and thus restrain susceptible BC cells in G1 phase. Three CDK4/6i are approved for the first-line treatment of patients with advanced/metastatic hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) BC in combination with endocrine therapy (ET). Though this has improved the clinical outcomes for survival of BC patients, there is no established standard next-line treatment to tackle drug resistance. Recent studies suggest that CDK4/6i can modulate other distinct effects in both BC and breast stromal compartments, which may provide new insights into aspects of their clinical activity. This review describes the biochemistry of the CDK4/6-Rb-E2F pathway in HR+ BC, then discusses how CDK4/6i can trigger other effects in BC/breast stromal compartments, and finally outlines the mechanisms of CDK4/6i resistance that have emerged in recent preclinical studies and clinical cohorts, emphasizing the impact of these findings on novel therapeutic opportunities in BC.

Renal cancer: signaling pathways and advances in targeted therapies

Renal cancer is a highlyheterogeneous malignancy characterized by rising global incidence and mortalityrates. The complex interplay and dysregulation of multiple signaling pathways,including von Hippel-Lindau (VHL)/hypoxia-inducible factor (HIF), phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR), Hippo-yes-associated protein (YAP), Wnt/ß-catenin, cyclic adenosine monophosphate (cAMP), and hepatocyte growth factor (HGF)/c-Met, contribute to theinitiation and progression of renal cancer. Although surgical resection is thestandard treatment for localized renal cancer, recurrence and metastasiscontinue to pose significant challenges. Advanced renal cancer is associatedwith a poor prognosis, and current therapies, such as targeted agents andimmunotherapies, have limitations. This review presents a comprehensiveoverview of the molecular mechanisms underlying aberrant signaling pathways inrenal cancer, emphasizing their intricate crosstalk and synergisticinteractions. We discuss recent advancements in targeted therapies, includingtyrosine kinase inhibitors, and immunotherapies, such as checkpoint inhibitors.Moreover, we underscore the importance of multiomics approaches and networkanalysis in elucidating the complex regulatory networks governing renal cancerpathogenesis. By integrating cutting-edge research and clinical insights, this review contributesto the development of innovative diagnostic and therapeutic strategies, whichhave the potential to improve risk stratification, precision medicine, andultimately, patient outcomes in renal cancer.

Hepatocyte growth factor promotes retinal pigment epithelium cell activity through MET/AKT signaling pathway

AIM

To explore the effects of hepatocyte growth factor (HGF) on retinal pigment epithelium (RPE) cell behaviors.

METHODS

The human adult retinal pigment epithelial cell line-19 (ARPE-19) were treated by HGF or mesenchymal-epithelial transition factor (MET) inhibitor SU11274 in vitro. Cell viability was detected by a Cell Counting Kit-8 assay. Cell proliferation and motility was detected by a bromodeoxyuridine incorporation assay and a wound healing assay, respectively. The expression levels of MET, phosphorylated MET, protein kinase B (AKT), and phosphorylated AKT proteins were determined by Western blot assay. The MET and phosphorylated MET proteins were also determined by immunofluorescence assay.

RESULTS

HGF increased ARPE-19 cells' viability, proliferation and migration, and induced an increase of phosphorylated MET and phosphorylated AKT proteins. SU11274 significantly reduced cell viability, proliferation, and migration and decreased the expression of MET and AKT proteins. SU11274 suppressed HGF-induced increase of viability, proliferation, and migration in ARPE-19 cells. Additionally, SU11274 also blocked HGF-induced phosphorylation of MET and AKT proteins.

CONCLUSION

HGF enhances cellular viability, proliferation, and migration in RPE cells through the MET/AKT signaling pathway, whereas this enhancement is suppressed by the MET inhibitor SU11274. HGF-induced MET/AKT signaling might be a vital contributor of RPE cells survival.

A Large Genetic Causal Analysis of the Gut Microbiota and Urological Cancers: A Bidirectional Mendelian Randomization Study

BACKGROUND

Several observational studies and clinical trials have shown that the gut microbiota is associated with urological cancers. However, the causal relationship between gut microbiota and urological cancers remains to be elucidated due to many confounding factors.

METHODS

In this study, we used two thresholds to identify gut microbiota GWAS from the MiBioGen consortium and obtained data for five urological cancers from the UK biobank and Finngen consortium, respectively. We then performed a two-sample Mendelian randomization (MR) analysis with Wald ratio or inverse variance weighted as the main method. We also performed comprehensive sensitivity analyses to verify the robustness of the results. In addition, we performed a reverse MR analysis to examine the direction of causality.

RESULTS

Our study found that family Rikenellaceae, genus Allisonella, genus Lachnospiraceae UCG001, genus Oscillibacter, genus Eubacterium coprostanoligenes group, genus Eubacterium ruminantium group, genus Ruminococcaceae UCG013, and genus Senegalimassilia were related to bladder cancer; genus Ruminococcus torques group, genus Oscillibacter, genus Barnesiella, genus Butyricicoccus, and genus Ruminococcaceae UCG005 were related to prostate cancer; class Alphaproteobacteria, class Bacilli, family Family XI, genus Coprococcus2, genus Intestinimonas, genus Lachnoclostridium, genus Lactococcus, genus Ruminococcus torques group, and genus Eubacterium brachy group were related to renal cell cancer; family Clostridiaceae 1, family Christensenellaceae, genus Eubacterium coprostanoligenes group, genus Clostridium sensu stricto 1, and genus Eubacterium eligens group were related to renal pelvis cancer; family Peptostreptococcaceae, genus Romboutsia, and genus Subdoligranulum were related to testicular cancer. Comprehensive sensitivity analyses proved that our results were reliable.

CONCLUSIONS

Our study confirms the role of specific gut microbial taxa on urological cancers, explores the mechanism of gut microbiota on urological cancers from a macroscopic level, provides potential targets for the screening and treatment of urological cancers, and is dedicated to providing new ideas for clinical research.

New pyrazolopyridine and pyrazolothiazole-based compounds as anti-proliferative agents targeting c-Met kinase inhibition: design, synthesis, biological evaluation, and computational studies

c-Met tyrosine kinase plays a key role in the oncogenic process. Inhibition of the c-Met has emerged as an attractive target for human cancer treatment. This work deals with the design and synthesis of a new set of derivatives bearing pyrazolo[3,4-b]pyridine, pyrazolo[3,4-b]thieno[3,2-e]pyridine, and pyrazolo[3,4-d]thiazole-5-thione scaffolds, 5a,b, 8a-f, and 10a,b, respectively, utilizing 3-methyl-1-tosyl-1H-pyrazol-5(4H)-one (1) as a key starting material. All the new compounds were evaluated as antiproliferative agents against HepG-2, MCF-7, and HCT-116 human cancer cell lines utilizing 5-fluorouracil and erlotinib as two standard drugs. Compounds 5a,b and 10a,b represented the most promising cytotoxic activity of IC₅₀ values ranging from 3.42 ± 1.31 to 17.16 ± 0.37 μM. Both 5a and 5b showed the most cytotoxicity and selectivity toward HepG-2, with IC₅₀ values of 3.42 ± 1.31 μM and 3.56 ± 1.5 μM, respectively. The enzyme assay demonstrated that 5a and 5b had inhibition potency on c-Met with IC₅₀ values in nanomolar range of 4.27 ± 0.31 and 7.95 ± 0.17 nM, respectively in comparison with the reference drug cabozantinib (IC₅₀; 5.38 ± 0.35 nM). The impact of 5a on the cell cycle and apoptosis induction potential in HepG-2 and on the apoptotic parameters; Bax, Bcl-2, p53, and caspase-3 was also investigated. Finally, the molecular docking simulation of the most promising derivatives 5a and 5b was screened against c-Met to investigate the binding patterns of both compounds in the active site of the c-Met enzyme. In silico ADME studies were also performed for 5a and 5b to predict their physicochemical and pharmacokinetic characteristics.