The HIV reverse transcriptase Inhibitor Tenofovir suppressed DMH/HFD-induced colorectal cancer in Wistar rats

Assessment of the therapeutic potential of a novel phosphoramidate acyclic nucleoside on induced hepatocellular carcinoma in rat model

AIMS

Hepatocellular Carcinoma (HCC) is renowned as a deadly primary cancer of hepatic origin. Sorafenib is the drug-of-choice for targeted treatment of unresectable end-stage HCC. Unfortunately, great proportion of HCC patients showed intolerance or unresponsiveness to treatment. This study assesses potency of novel ProTide; SH-PAN-19 against N-Nitrosodiethylamine (DEN)-induced HCC in male Wistar rats, compared to Sorafenib.

MAIN METHODS

Structural entity of the synthesized compound was substantiated via FT-IR, UV-Vis, 1H NMR and 13C NMR spectroscopic analysis. In vitro, SH-PAN-19 cytotoxicity was tested against 3 human cell lines; hepatocellular carcinoma; HepG-2, colorectal carcinoma; HCT-116 and normal fibroblasts; MRC-5. In vivo, therapeutic efficacy of SH-PAN-19 (300 mg/kg b.w./day) against HCC could be revealed and compared to that of Sorafenib (15 mg/kg b.w./day) by evaluating the morphometric, biochemical, histopathological, immunohistochemical and molecular key markers.

KEY FINDINGS

SH-PAN-19 was relatively safe toward MRC-5 cells (IC50 = 307.6 μg/mL), highly cytotoxic to HepG-2 cells (IC50 = 24.9 μg/mL) and prominently hepato-selective (TSI = 12.35). Oral LD50 of SH-PAN-19 was >3000 mg/kg b.w. DEN-injected rats suffered hepatomegaly, oxidative stress, elevated liver enzymes, hypoalbuminemia, bilirubinemia and skyrocketed AFP plasma titre. SH-PAN-19 alleviated the DEN-induced alterations in apoptotic, angiogenic and inflammatory markers. SH-PAN-19 produced a 2.5-folds increase in Caspase-9 and downregulated VEGFR-2, IL-6, TNF-α, TGFβ-1, MMP-9 and CcnD-1 to levels comparable to that elicited by Sorafenib. SH-PAN-19 resulted in near-complete pathological response versus partial response achieved by Sorafenib.

SIGNIFICANCE

This research illustrated that SH-PAN-19 is a promising chemotherapeutic agent capable of restoring cellular plasticity and could stop HCC progression.

Current trends and future prospects of drug repositioning in gastrointestinal oncology

Gastrointestinal (GI) cancers comprise a significant number of cancer cases worldwide and contribute to a high percentage of cancer-related deaths. To improve survival rates of GI cancer patients, it is important to find and implement more effective therapeutic strategies with better prognoses and fewer side effects. The development of new drugs can be a lengthy and expensive process, often involving clinical trials that may fail in the early stages. One strategy to address these challenges is drug repurposing (DR). Drug repurposing is a developmental strategy that involves using existing drugs approved for other diseases and leveraging their safety and pharmacological data to explore their potential use in treating different diseases. In this paper, we outline the existing therapeutic strategies and challenges associated with GI cancers and explore DR as a promising alternative approach. We have presented an extensive review of different DR methodologies, research efforts and examples of repurposed drugs within various GI cancer types, such as colorectal, pancreatic and liver cancers. Our aim is to provide a comprehensive overview of employing the DR approach in GI cancers to inform future research endeavors and clinical trials in this field.

The role of gut microbiota and drug interactions in the development of colorectal cancer

The human gut microbiota is a complex ecosystem regulating the host's environmental interaction. The same functional food or drug may have varying bioavailability and distinct effects on different individuals. Drugs such as antibiotics can alter the intestinal flora, thus affecting health. However, the relationship between intestinal flora and non-antibiotic drugs is bidirectional: it is not only affected by drugs; nevertheless, it can alter the drug structure through enzymes and change the bioavailability, biological activity, or toxicity of drugs to improve their efficacy and safety. This review summarizes the roles and mechanisms of antibiotics, antihypertensive drugs, nonsteroidal anti-inflammatory drugs, lipid-lowering drugs, hypoglycemic drugs, virus-associated therapies, metabolites, and dietary in modulating the colorectal cancer gut microbiota. It provides a reference for future antitumor therapy targeting intestinal microorganisms.

Tenofovir alone or combined with doxorubicin abrogates DMBA-induced mammary cell carcinoma: An insight into its modulatory impact on oxidative/Notch/apoptotic signaling

AIMS

Breast cancer incidence keeps on growing and emerging as one of the major global challenges, therefore, the introduction of new approaches is of great demand. Drug repurposing is crucial to faster and cheaper discovery of anti-cancer drugs. The antiviral tenofovir disproxil fumarate (TF) was reported to decrease hepatocellular carcinoma risk by interfering with cell cycle and proliferation. This study aimed to scrutinize the role of TF alone or combined with doxorubicin (DOX) in 7,12-dimethylbenz (a) anthracene (DMBA)-induced breast carcinoma rat model.

MATERIALS AND METHODS

Breast carcinoma was induced by DMBA (7.5 mg/kg, twice/week, SC into mammary gland) for 4 successive weeks. TF (25 and 50 mg/kg/day) was given orally and DOX (2 mg/kg) was injected once/week by tail vein starting from day 1.

KEY FINDINGS

The anti-cancerous effect of TF was mediated by suppression of oxidative stress markers and Notch signaling proteins (Notch1, JAG1, and HES1), attenuation of tumor proliferation markers (cyclin-D1 and Ki67), and boosting of apoptosis (P53 and Caspase3) and autophagy biomarkers (Beclin1 and LC3). In parallel, histopathological assessment displayed that mammary glands from animals treated with TF alone or combined with DOX showed better histopathological scores. Interestingly, TF and DOX co-treatment markedly decreased myocardial injury markers (AST, LDH, and CK-MB), restored the balance between GSH and ROS, prohibited lipid peroxidation, and preserved microscopic myocardial architecture.

SIGNIFICANCE

TF elicited antitumor activity via multiple molecular mechanisms. Moreover, combining TF with DOX might be a potential novel strategy to enhance DOX-anticancer activity and decrease its cardiac side effects.

The Potential Chemopreventive Effect of Andrographis paniculata on 1,2-Dimethylhydrazine and High-Fat-Diet-Induced Colorectal Cancer in Sprague Dawley Rats

Colorectal cancer (CRC) is responsible for a notable rise in the overall mortality rate. Obesity is found to be one of the main factors behind CRC development. Andrographis paniculata is a herbaceous plant famous for its medicinal properties, particularly in Southeast Asia for its anti-cancer properties. This study examines the chemopreventive impact of A. paniculata ethanolic extract (APEE) against a high-fat diet and 1,2-dimethylhydrazine-induced colon cancer in Sprague Dawley rats. Sprague Dawley rats were administered 1,2-dimethylhydrazine (40 mg/kg, i.p. once a week for 10 weeks) and a high-fat diet (HFD) for 20 weeks to induce colorectal cancer. APEE was administered at 125 mg/kg, 250 mg/kg, and 500 mg/kg for 20 weeks. At the end of the experiment, blood serum and organs were collected. DMH/HFD-induced rats had abnormal crypts and more aberrant crypt foci (ACF). APEE at a dose of 500 mg/kg improved the dysplastic state of the colon tissue and caused a 32% reduction in the total ACF. HFD increased adipocyte cell size, while 500 mg/kg APEE reduced it. HFD and DMH/HFD rats had elevated serum insulin and leptin levels. Moreover, UHPLC-QTOF-MS analysis revealed that APEE was rich in anti-cancer phytochemicals. This finding suggests that APEE has anti-cancer potential against HFD/DMH-induced CRC and anti-adipogenic and anti-obesity properties.

Overcoming Therapy Resistance in Colon Cancer by Drug Repurposing

Simple Summary

Despite improvements in standardized screening methods and the development of promising therapies for colorectal cancer (CRC), survival rates are still low. Drug repurposing offers an affordable solution to achieve new indications for previously approved drugs that could play a protagonist or adjuvant role in the treatment of CRC. In this review, we summarize the current data supporting drug repurposing as a feasible option for patients with CRC.

Abstract

Colorectal cancer (CRC) is the third most common cancer in the world. Despite improvement in standardized screening methods and the development of promising therapies, the 5-year survival rates are as low as 10% in the metastatic setting. The increasing life expectancy of the general population, higher rates of obesity, poor diet, and comorbidities contribute to the increasing trends in incidence. Drug repurposing offers an affordable solution to achieve new indications for previously approved drugs that could play a protagonist or adjuvant role in the treatment of CRC with the advantage of treating underlying comorbidities and decreasing chemotherapy toxicity. This review elaborates on the current data that supports drug repurposing as a feasible option for patients with CRC with a focus on the evidence and mechanism of action promising repurposed candidates that are widely used, including but not limited to anti-malarial, anti-helminthic, anti-inflammatory, anti-hypertensive, anti-hyperlipidemic, and anti-diabetic agents.

Viruses in colorectal cancer

Increasing evidence suggests that microorganisms might represent at least highly interesting cofactors in colorectal cancer (CRC) oncogenesis and progression. Still, associated mechanisms, specifically in colonocytes and their microenvironmental interactions, are still poorly understood. Although, currently, at least seven viruses are being recognized as human carcinogens, only three of these – Epstein–Barr virus (EBV), human papillomavirus (HPV) and John Cunningham virus (JCV) – have been described, with varying levels of evidence, in CRC. In addition, cytomegalovirus (CMV) has been associated with CRC in some publications, albeit not being a fully acknowledged oncovirus. Moreover, recent microbiome studies set increasing grounds for new hypotheses on bacteriophages as interesting additional modulators in CRC carcinogenesis and progression. The present Review summarizes how particular groups of viruses, including bacteriophages, affect cells and the cellular and microbial microenvironment, thereby putatively contributing to foster CRC. This could be achieved, for example, by promoting several processes – such as DNA damage, chromosomal instability, or molecular aspects of cell proliferation, CRC progression and metastasis – not necessarily by direct infection of epithelial cells only, but also by interaction with the microenvironment of infected cells. In this context, there are striking common features of EBV, CMV, HPV and JCV that are able to promote oncogenesis, in terms of establishing latent infections and affecting p53‐/pRb‐driven, epithelial–mesenchymal transition (EMT)‐/EGFR‐associated and especially Wnt/β‐catenin‐driven pathways. We speculate that, at least in part, such viral impacts on particular pathways might be reflected in lasting (e.g. mutational or further genomic) fingerprints of viruses in cells. Also, the complex interplay between several species within the intestinal microbiome, involving a direct or indirect impact on colorectal and microenvironmental cells but also between, for example, phages and bacterial and viral pathogens, and further novel species certainly might, in part, explain ongoing difficulties to establish unequivocal monocausal links between specific viral infections and CRC.