Molecular markers and Schistosoma-associated bladder carcinoma: A systematic review and meta-analysis

From the discovery of helminths to the discovery of their carcinogenic potential

Cancer involves a major aberration in the normal behaviour of cells, making them divide continuously, which interferes with the normal physiology of the body. The link between helminths and their cancer-inducing potential has been proposed in the last century. The exact pathway is still not clear but chronic inflammation in response to the deposited eggs, immune response against soluble egg antigens, and co-infection with a third party (a bacteria, a virus, or infection leading to a change in microbiome) seems to be the reasons for cancer induction. This review looks into the historical outlook on helminths along with their epidemiology, morphology, and life cycle. It then focuses on providing correlations between helminth infection and molecular mechanism of carcinogenesis by elaborating upon epidemiological, clinical, and surgical studies. While the cancer-inducing potential has been convincingly established only for a few helminths and studies point out towards possible cancer-inducing ability of the rest of the helminths elucidated in this work, however, more insights into the immunobiology of helminths as well as infected patients are required to conclusively comment upon this ability of the latter.

Bladder carcinomas in patients with neurogenic bladder and urinary schistosomiasis: are they the same tumors?

PURPOSE

The aim of our study was to evaluate and compare the expression of different immunohistochemical markers in Bladder Carcinomas (BC) in patients with Neurogenic Bladder (NB) and Urinary Schistosomiasis (US) infection.

MATERIALS AND METHODS

We collected tissue samples from patients with Neurogenic Bladder and Bladder Carcinoma (NBC Group) and from patients with Urinary Schistosomiasis infection and Bladder Carcinoma (SBC Group). We compared to these two groups to control samples from resection from patients with Urinary Schistosomiasis without Bladder Carcinoma (US Group); we also investigate patients' characteristics according to urothelial transitional cell carcinoma (TCC), and squamous cell carcinoma (SCC) histopathological differentiation. The expression of markers in all groups (CK7, CK14, CK20, FoxP3, GATA3, STAG2, CD3, CD8, Ki67, and P53) was analyzed using immunohistochemistry of tissue micro-array sections (TMA).

RESULTS

Overall, 136 patients were included in the study (n = 72 in the NBC group, n = 33 in the SBC group, and n = 31 in the US group). In the TCC subgroup, the expression of CK7, CK14, CK20, and Ki67 was significantly higher compared to US controls (p 0.002; p < 0.001; p 0.036; p < 0.001). In the SCC subgroup, the expression of CK7, CK14, and CK20 was significantly higher compared to US controls (p 0.007; p < 0.001; p 0.005). Both in TCC and SCC subgroups, no difference in the expression of any tested markers was found comparing NBC and SBC groups. In US group, a significant higher expression of STAG2 was found compared to SCC subgroup (p 0.005).

CONCLUSION

Based on our results, the profile of immunohistochemical biomarkers' expression in both NBC and SBC groups is similar.

Camptothecin shows better promise than Curcumin in the inhibition of the Human Telomerase: A computational study

OBJECTIVES

The Human Telomerase enzyme has become a drug target in the treatment of cancers and age-related disorders. This study aims to identify potential natural inhibitors of the Human Telomerase from compounds derived from edible African plants.

MATERIALS AND METHODS

A library of 1,126 natural compounds was molecularly docked against the Telomerase Reverse Transcriptase (PDB ID: 5ugw), the catalytic subunit of the target protein. Curcumin, a known Telomerase inhibitor was used as the standard. The front-runner compounds were screened for bioavailability, pharmacokinetic properties, and bioactivity using the SWISSADME, PKCSM, and Molinspiration webservers respectively. The molecular dynamic simulation and analyses of the apo and holo proteins were performed by the Galaxy supercomputing webserver.

RESULTS

The results of the molecular docking and virtual screening reveal Augustamine and Camptothecin as lead compounds. Augustamine has better drug-likeness and pharmacokinetic properties while Camptothecin showed better bioactivity and stronger binding affinity (-8.2 kcal/mol) with the target. The holo structure formed by Camptothecin showed greater inhibitory activity against the target with a total RMSF of 169.853, B-Factor of 20.164, and 108 anti-correlating residues.

CONCLUSION

Though they both act at the same binding site, Camptothecin induces greater Telomerase inhibition and better molecular stability than the standard, Curcumin. Further tests are required to investigate the inhibitory activities of the lead compounds.

Interleukin-4 Signaling Plays a Major Role in Urogenital Schistosomiasis-Associated Bladder Pathogenesis

Interleukin-4 (IL-4) is crucial in many helminth infections, but its role in urogenital schistosomiasis, infection with Schistosoma haematobium worms, remains poorly understood due to a historical lack of animal models. The bladder pathology of urogenital schistosomiasis is caused by immune responses to eggs deposited in the bladder wall. A range of pathology occurs, including urothelial hyperplasia and cancer, but associated mechanisms and links to IL-4 are largely unknown. We modeled urogenital schistosomiasis by injecting the bladder walls of IL-4 receptor-alpha knockout (Il4ra-/- ) and wild-type mice with S. haematobium eggs. Readouts included bladder histology and ex vivo assessments of urothelial proliferation, cell cycle, and ploidy status. We also quantified the effects of exogenous IL-4 on urothelial cell proliferation in vitro, including cell cycle status and phosphorylation patterns of major downstream regulators in the IL-4 signaling pathway. There was a significant decrease in the intensity of granulomatous responses to bladder-wall-injected S. haematobium eggs in Il4ra-/- versus wild-type mice. S. haematobium egg injection triggered significant urothelial proliferation, including evidence of urothelial hyper-diploidy and cell cycle skewing in wild-type but not Il4ra-/- mice. Urothelial exposure to IL-4 in vitro led to cell cycle polarization and increased phosphorylation of AKT. Our results show that IL-4 signaling is required for key pathogenic features of urogenital schistosomiasis and that particular aspects of this signaling pathway may exert these effects directly on the urothelium. These findings point to potential mechanisms by which urogenital schistosomiasis promotes bladder carcinogenesis.

Understanding Urogenital Schistosomiasis-Related Bladder Cancer: An Update

Infection with Schistosoma haematobium leads to urogenital schistosomiasis, which has been correlated with the occurrence of bladder cancer. However, mechanisms responsible for this association have not yet been clearly identified. In this short review, we provide an update, highlighting the most recent studies on schistosome-associated bladder cancer, including those that focus on identifying changes in host biology during S. haematobium infection, as well as studies for the identification of potentially pro-carcinogenic parasite molecules, and we offer a discussion on some possible mechanisms driving schistosomal bladder cancer.

Recombinant adenovirus-p53 enhances the therapeutic effect of surgery and chemoradiotherapy combination in hypopharyngeal squamous cell carcinomas patients

The purpose of our study was to assess the safety and efficacy of recombinant adenovirus-p53 (rAd-p53) combined with surgery and chemoradiotherapy (CRT) for patients with hypopharyngeal squamous cell carcinomas (HPSCC). This study retrospectively and consecutively collected clinical data of 102 patients with primary HPSCC who were admitted to the Department of Otolaryngology of West China Hospital, Sichuan University in China between March 2010 and December 2015. A retrospective clinical study of 102 patients with HPSCC was carried out from March 2010 to December 2015. All patients were male and were divided into 3 groups based on the treatments they received, including Single Surgery, Surgery + CRT, and Surgery + CRT + rAd-p53. In the Surgery + CRT + rAd-p53 group, rAd-p53 was intratumorally injected on the 1st day preoperatively; peritumorally injected on the 7th day intraoperatively, and on the 21st, 28th, and 35th days postoperatively. Their clinical data were retrospectively collected and analyzed. In our study, for all 102 patients with HPSCC, 16 patients received Single Surgery, 44 patients received Surgery + CRT therapy, and 42 patients received Surgery + CRT + rAd-p53 therapy. In the Surgery + CRT + rAd-p53 group, all patients could tolerate rAd-p53 treatment and no serious side effect was observed. In addition, rAd-p53 application did not increase the side reactions caused by surgery and CRT. Compared with the 3-year overall survival rates of Single Surgery group and Surgery + CRT group, the 3-year overall survival rates of Surgery + CRT + rAd-p53 group was significantly enhanced (P < .05). Similar results were also observed for the 3-year disease-free survival rates. Our results indicate that rAd-p53 therapy may improve the therapeutic effect of patients with HPSCC, and is a safe and effective treatment method for patients with HPSCC. However, further prospective studies with larger sample sizes are needed to validate our findings.

Helminths and Cancers From the Evolutionary Perspective

Helminths include free-living and parasitic Platyhelminthes and Nematoda which infect millions of people worldwide. Some Platyhelminthes species of blood flukes (Schistosoma haematobium, Schistosoma japonicum, and Schistosoma mansoni) and liver flukes (Clonorchis sinensis and Opisthorchis viverrini) are known to be involved in human cancers. Other helminths are likely to be carcinogenic. Our main goals are to summarize the current knowledge of human cancers caused by Platyhelminthes, point out some helminth and human biomarkers identified so far, and highlight the potential contributions of phylogenetics and molecular evolution to cancer research. Human cancers caused by helminth infection include cholangiocarcinoma, colorectal hepatocellular carcinoma, squamous cell carcinoma, and urinary bladder cancer. Chronic inflammation is proposed as a common pathway for cancer initiation and development. Furthermore, different bacteria present in gastric, colorectal, and urogenital microbiomes might be responsible for enlarging inflammatory and fibrotic responses in cancers. Studies have suggested that different biomarkers are involved in helminth infection and human cancer development; although, the detailed mechanisms remain under debate. Different helminth proteins have been studied by different approaches. However, their evolutionary relationships remain unsolved. Here, we illustrate the strengths of homology identification and function prediction of uncharacterized proteins from genome sequencing projects based on an evolutionary framework. Together, these approaches may help identifying new biomarkers for disease diagnostics and intervention measures. This work has potential applications in the field of phylomedicine (evolutionary medicine) and may contribute to parasite and cancer research.

Telomerase Inhibitors from Natural Products and Their Anticancer Potential

Telomeres and telomerase are nowadays exploring traits on targets for anticancer therapy. Telomerase is a unique reverse transcriptase enzyme, considered as a primary factor in almost all cancer cells, which is mainly responsible to regulate the telomere length. Hence, telomerase ensures the indefinite cell proliferation during malignancy—a hallmark of cancer—and this distinctive feature has provided telomerase as the preferred target for drug development in cancer therapy. Deactivation of telomerase and telomere destabilization by natural products provides an opening to succeed new targets for cancer therapy. This review aims to provide a fundamental knowledge for research on telomere, working regulation of telomerase and its various binding proteins to inhibit the telomere/telomerase complex. In addition, the review summarizes the inhibitors of the enzyme catalytic subunit and RNA component, natural products that target telomeres, and suppression of transcriptional and post-transcriptional levels. This extensive understanding of telomerase biology will provide indispensable information for enhancing the efficiency of rational anti-cancer drug design.

The role of estradiol metabolism in urogenital schistosomiasis-induced bladder cancer

Urogenital schistosomiasis is a neglected tropical disease that can lead to bladder cancer. How urogenital schistosomiasis induces carcinogenesis remains unclear, although there is evidence that the human blood fluke Schistosoma haematobium, the infectious agent of urogenital schistosomiasis, releases estradiol-like metabolites. These kind of compounds have been implicated in other cancers. Aiming for enhanced understanding of the pathogenesis of the urogenital schistosomiasis-induced bladder cancer, here we review, interpret, and discuss findings of estradiol-like metabolites detected in both the parasite and in the human urine during urogenital schistosomiasis. Moreover, we predict pathways and enzymes that are involved in the production of these metabolites emphasizing their potential effects on the dysregulation of the tumor suppressor gene p53 expression during urogenital schistosomiasis. Enhanced understanding of these potential carcinogens may not only shed light on urogenital schistosomiasis-induced neoplasia of the bladder, but would also facilitate development of interventions and biomarkers for this and other infection-associated cancers at large.