The therapeutic potential of renin-angiotensin system inhibitors in the treatment of pancreatic cancer

Synergistic effects of calcium channel blockers and renin-angiotensin inhibitors with gemcitabine-based chemotherapy on the survival of patients with pancreatic cancer

PURPOSE

Pancreatic cancer remains a significant public health challenge, with poor long-term outcomes due to the lack of effective treatment options. Repurposing commonly used clinical drugs, such as ACE inhibitors, ARBs, CCBs, and metformin, may enhance the efficacy of chemotherapy and offer a promising therapeutic strategy for improving patient outcomes.

METHODS

A retrospective analysis of concomitant treatment with ACE-Is, ARBs, CCBs, and metformin alongside gemcitabine chemotherapy in patients with pancreatic cancer was conducted. Treatment responses were evaluated, with overall survival (OS) estimated using the Kaplan-Meier method. Additionally, the Cox proportional hazards model was employed to assess the impact of these specific agents on patient survival.

RESULTS

4628 patients with various stages of pancreatic cancer were identified in the database between 2007 and 2016. The estimated overall survival (OS) in the analyzed group was 6.9 months (95% CI 6.4-7). The use of any of the analyzed drugs was associated with a significant improvement in mOS of 7.5 months (95% CI 6.8-7.8) vs. 6.7 months (95% CI 6.4-7.0) for patients who did not have additional treatment (p < 0.0001). ARBs, ACE-Is, CCBs, and metformin varied in their effectiveness in prolonging mOS among patients. The longest mOS of 8.9 months (95% CI 7.7-11.6) was observed in patients receiving additional therapy with ARBs, while the shortest mOS of 7.7 months (95% CI 6.5-8.9) was achieved by patients receiving metformin. In the adjusted Cox analysis, metformin was associated with a significantly weaker effect on mOS (p = 0.029). A particularly interesting trend in prolonging 5-year survival was demonstrated by ARBs and CCBs with 14.1% (95% CI 9-22%) and 14.8% (95% CI 11.1-19.6%), respectively, compared to patients not taking these drugs, who achieved a 5-year OS of 3.8% (95% CI 3.2-4.4%).

CONCLUSION

Our results demonstrate a significant positive impact of ARBs, ACE inhibitors, and CCBs on survival in patients with pancreatic cancer treated with gemcitabine. The addition of these inexpensive and relatively safe drugs in patients with additional comorbidities may represent a potential therapeutic option in this indication. However, prospective clinical trials to evaluate the optimal patient population and further studies to determine the potential impact of these agents on chemotherapy are necessary.

The Counteracting Effects of Ang II and Ang-(1-7) on the Function andGrowth of Insulin-secreting NIT-1 Cells

INTRODUCTION

China now has the highest number of diabetes in the world. Angiotensin II (Ang II) causes insulin resistance by acting on the insulin signaling pathway of peripheral target tissues. However, its effect on islet β-cells remains unclear. The possible role of Angiotensin-( 1-7) [Ang-(1-7)] as an antagonist to the effects of Ang II and in treating diabetes needs to be elucidated.

OBJECTIVES

To assess the effects of Ang II and Ang-(1-7) on the function and growth of islet β cell line NIT-1, which is derived from the islets of non-obese diabetic/large T-antigen (NOD/LT) mice with insulinoma.

METHODS

NIT-1 cells were treated with Ang II, Ang-(1-7) and their respective receptor antagonists. The impact on cell function and growth was then evaluated.

RESULTS

Ang II significantly reduced insulin-stimulated IR-β-Tyr and Akt-Ser; while Ang-(1-7), saralasin (an Ang II receptor antagonist), and diphenyleneiodonium [DPI, a nicotinamide adenine dinucleotide phosphate oxidase (NOX) antagonist] reversed the inhibiting effect. Conversely, Ang II significantly increased insulin-stimulated intracellular H2O2 and P47 phox, while saralasin and DPI reverted the effect. Furthermore, Ang-(1-7) reduced the elevated concentrations of ROS and MDA while increasing the proliferation rate that was reduced by high glucose, all of which were reversed by A-779, an antagonist of the Mas receptor (MasR).

CONCLUSION

Angiotensin II poses a negative regulatory effect on insulin signal transduction, increases oxidative stress, and may inhibit the transcription of insulin genes stimulated by insulin in NIT-1 cells. Meanwhile, angiotensin-(1-7) blocked these effects via MasR. These results corroborate the rising potential of the renin-angiotensin system (RAS) in treating diabetes.

The renin-angiotensin-aldosterone system (RAAS) signaling pathways and cancer: foes versus allies

The renin-angiotensin-aldosterone system (RAAS), is an old system with new fundamental roles in cancer biology which influences cell growth, migration, death, and metastasis. RAAS signaling enhances cell proliferation in malignancy directly and indirectly by affecting tumor cells and modulating angiogenesis. Cancer development may be influenced by the balance between the ACE/Ang II/AT1R and the ACE2/Ang 1-7/Mas receptor pathways. The interactions between Ang II/AT1R and Ang I/AT2R as well as Ang1-7/Mas and alamandine/MrgD receptors in the RAAS pathway can significantly impact the development of cancer. Ang I/AT2R, Ang1-7/Mas, and alamandine/MrgD interactions can have anticancer effects while Ang II/AT1R interactions can be involved in the development of cancer. Evidence suggests that inhibitors of the RAAS, which are conventionally used to treat cardiovascular diseases, may be beneficial in cancer therapies.Herein, we aim to provide a thorough description of the elements of RAAS and their molecular play in cancer. Alongside this, the role of RAAS components in sex-dependent cancers as well as GI cancers will be discussed with the hope of enlightening new venues for adjuvant cancer treatment.

Screening of Differentially Expressed Genes Based on the ACRG Molecular Subtypes of Gastric Cancer and the Significance and Mechanism of AGTR1 Gene Expression

BACKGROUND

The Asian Cancer Research Group (ACRG) classification is a molecular classification established based on the tissues of gastric cancer (GC) patients in Asia. Patients with different ACRG subtypes differ significantly with regard to treatment response and prognosis, which indicates that the ACRG molecular classification is more valuable than the traditional pathological classification. However, the specific differentially expressed genes (DEGs) and the value of the ACRG molecular subtypes of GC have not been studied in depth.

METHODS

Through the analysis of the GEO database, the DEGs in GC tissues of different ACRG molecular subtypes were investigated. The expression and mechanism of the screened angiotensin II receptor type 1 (AGTR1) gene were bioinformatically analyzed and experimentally verified. The role of AGTR1 in GC cells was mainly investigated using CCK-8, wound-healing, transwell invasion assays, qRT-PCR, and Western blotting.

RESULTS

The bioinformatics results showed the presence of multiple DEGs in GC tissues with different ACRG molecular subtypes. Certain DEGs in GC tissues of different ACRG molecular subtypes have prognostic significance. AGTR1 levels in tumor tissues were significantly higher than in paired paracancerous tissues. The prognosis of GC patients with high expression of AGTR1 was poor (p < 0.05). The AGTR1 gene in GC samples was associated with the expression of immune pathways and immune checkpoint genes. After modifying AGTR1 expression in cell lines, cells' proliferation, invasion, and migration abilities and the expression of related genes changed.

CONCLUSIONS

There were significant DEGs in GC tissues with different ACGR molecular types, among which the increased expression of AGTR1 was a molecular feature of MSS/EMT type gastric cancer. Further study found that AGTR1 was closely related to tumor immune infiltration and invasion and may be a new therapeutic target gene for gastric cancer.

Concentrations of Transition Metal Ions in Rat Lungs after Tobacco Smoke Exposure and Treatment with His-Leu Dipeptide

Tobacco smoking is deleterious to the lungs because it exposes them to many toxic substances. These include transition metal ions, such as cadmium. However, there is a lack of information about the influence of endogenous metal-binding peptides, such as His-Leu (HL), on the lung distribution of transition metals in smokers. To address this, we administered HL subcutaneously to rats exposed to tobacco smoke for six weeks, then we measured the concentrations of transition metal ions in the lungs. We found that exposure to tobacco smoke elevates the concentrations of Cd(II) and Cu(II). Administration of the HL peptide, whose elevation is a consequence of angiotensin receptor blocker anti-hypertension therapy, increases the concentration of Fe in the lungs of rats exposed to smoke. These findings suggest that smoking is a risk factor for patients receiving angiotensin receptor blockers to treat hypertension.

Breaking the Bottleneck in Anticancer Drug Development: Efficient Utilization of Synthetic Biology

Natural products have multifarious bioactivities against bacteria, fungi, viruses, cancers and other diseases due to their diverse structures. Nearly 65% of anticancer drugs are natural products or their derivatives. Thus, natural products play significant roles in clinical cancer therapy. With the development of biosynthetic technologies, an increasing number of natural products have been discovered and developed as candidates for clinical cancer therapy. Here, we aim to summarize the anticancer natural products approved from 1950 to 2021 and discuss their molecular mechanisms. We also describe the available synthetic biology tools and highlight their applications in the development of natural products.

Antihypertensive Drugs and Cancer Risk

Hypertension is the most prevalent comorbidity in cancer patients. Consequently, many cancer patients are prescribed antihypertensive drugs before cancer diagnosis or during cancer treatment. However, whether antihypertensive drugs affect the incidence, treatment efficacy, or prognosis of cancer remains unanswered. For instance, renin-angiotensin and β-adrenergic signaling may be involved not only in blood pressure elevation but also in cell proliferation, angiogenesis, and tissue invasion. Therefore, the inhibition of these pathways may have beneficial effects on cancer prevention or treatment. In this article, we reviewed several studies regarding antihypertensive drugs and cancer. In particular, we focused on the results of clinical trials to evaluate whether the use of antihypertensive drugs affects future cancer risk and prognosis. Unfortunately, the results are somewhat inconsistent, and evidence demonstrating the effect of antihypertensive drugs remains limited. We indicate that the heterogeneity in the study designs makes it difficult to clarify the causal relationship between antihypertensive drugs and cancer. We also propose that additional experimental studies, including research with induced pluripotent cells derived from cancer patients, single-cell analyses of cancer cell clusters, and clinical studies using artificial intelligence electronic health record systems, might be helpful to reveal the precise association between antihypertensive drugs and cancer risk.

Angiotensin-converting Enzyme Inhibitors and Angiotensin Receptor Blockers as Potential Therapeutic Options for Pancreatic Cancer

The renin-angiotensin system (RAS) has been reported to have a role in carcinogenesis, and therefore it may be of value as a potential therapeutic target in inhibiting tumor growth. It has been shown that inhibition of RAS via angiotensin I-converting enzyme inhibitors (ACEIs) and angiotensin II type-1 receptor (ARBs) inhibitors may have a protective effect against several malignancies. Here, we provide an overview of the potential value of the RAS pathway and targeting via ACE/ARB inhibitors in pancreatic cancer. Whilst the potential role of RAS as a target for the treatment of pancreatic cancer has been reported, the use of candesartan with gemcitabine failed to improve outcomes in pancreatic cancer. Another study of 1-3 years using ARB was found to reduce the risk of pancreatic cancer. In line with these trials, others have demonstrated that the ARBs in combination with gemcitabine might improve clinical outcomes in patients with advanced pancreatic cancer. Prospective trials are warranted to investigate this hypothesis.

Potential Prognostic Biomarkers of OSBPL Family Genes in Patients with Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly fatal malignancy with poor survival outcomes. In addition, oxysterol-binding protein-like (OSBPL) family members are reported to be involved in lipid binding and transport and play critical roles in tumorigenesis. However, relationships between PDAC and OSBPL family members have not comprehensively been elucidated. In this study, we used the Oncomine and GEPIA 2 databases to analyze OSBPL transcription expressions in PDAC. The Kaplan–Meier plotter and TIMER 2.0 were used to assess the relationships between overall survival (OS) and immune-infiltration with OSBPL family members. Co-expression data from cBioPortal were downloaded to assess the correlated pathways with OSBPL gene family members using DAVID. The expressions of OSBPL3, OSBPL8, OSBPL10, and OSBPL11 were found to be highly upregulated in PDAC. Low expressions of OSBPL3, OSBPL8, and OSBPL10 indicated longer OS. The functions of OSBPL family members were mainly associated with several potential signaling pathways in cancer cells, including ATP binding, integrin binding, receptor binding, and the renin-angiotensin system (RAS) signaling pathway. The transcription levels of OSBPL gene family members were connected with several immune infiltrates. Collectively, OSBPL family members are influential biomarkers for the early diagnosis of PDAC and have prognostic value, with the promise of precise treatment of PDAC in the future.

Drug Repurposing, an Attractive Strategy in Pancreatic Cancer Treatment: Preclinical and Clinical Updates

Pancreatic cancer (PC) is one of the deadliest malignancies worldwide, since patients rarely display symptoms until an advanced and unresectable stage of the disease. Current chemotherapy options are unsatisfactory and there is an urgent need for more effective and less toxic drugs to improve the dismal PC therapy. Repurposing of non-oncology drugs in PC treatment represents a very promising therapeutic option and different compounds are currently being considered as candidates for repurposing in the treatment of this tumor. In this review, we provide an update on some of the most promising FDA-approved, non-oncology, repurposed drug candidates that show prominent clinical and preclinical data in pancreatic cancer. We also focus on proposed mechanisms of action and known molecular targets that they modulate in PC. Furthermore, we provide an explorative bioinformatic analysis, which suggests that some of the PC repurposed drug candidates have additional, unexplored, oncology-relevant targets. Finally, we discuss recent developments regarding the immunomodulatory role displayed by some of these drugs, which may expand their potential application in synergy with approved anticancer immunomodulatory agents that are mostly ineffective as single agents in PC.