Effect of frequently prescribed drugs on gastric cancer risk

Intake of Proton-Pump Inhibitors and Gastric Cancer within the Stomach Cancer Pooling (StoP) Project

BACKGROUND

A potential association between proton-pump inhibitors (PPI) and gastric cancer remains undefined. Thus, we aimed to evaluate such association within the Stomach cancer Pooling (StoP) Project.

METHODS

Data from five case-control studies of the StoP Project were included (1,889 cases and 6,517 controls). We assessed the impact of different exposure definitions, specifically any reported use of PPIs and exposure definitions based on the duration of PPI intake. Additionally, we modeled the dose-response relationship between the cumulative duration of PPI intake and gastric cancer.

RESULTS

Significant associations between PPI intake and gastric cancer, both overall and in the stratified analyses, were limited to exposure definitions based on short durations of intake. The overall odds ratio (OR) for any reported PPI intake was 1.78 [95% confidence interval (CI): 0.76-4.14]. In the dose-response analysis, the ORs of gastric cancer were found to be higher for short durations of PPI intake (6 months: OR 3.26; 95% CI: 2.40-4.42; one year: OR 2.14; 95% CI: 1.69-2.70; 2 years: OR 1.50; 95% CI: 1.22-1.85; 3 years: OR 1.27; 95% CI: 1.03-1.56), with the association becoming not significant for durations longer than 3 years.

CONCLUSIONS

Our findings suggest that the observed association between PPIs and gastric cancer might be mainly due to reverse causality.

IMPACT

The results of this study suggest that PPIs are a safe therapeutic choice regarding their effect on the occurrence of gastric cancer. See related commentary by Richman and Leiman, p. 1127.

Phenolic-rich extract of Nopalea cochenillifera attenuates gastric lesions induced in experimental models through inhibiting oxidative stress, modulating inflammatory markers and a cytoprotective effect

Nopalea cochenillifera (Cactaceae), popularly known as "palma" or "palma doce", is from Mexico, but it was widely introduced in Brazil through crops. It has been used as food and in traditional medicine and is a good source of phenolic compounds. In this study the phytochemical profile and gastroprotective activity of phenolic-rich extract of N. cochenillifera in acute gastric lesion models induced by ethanol and indomethacin were evaluated. High-performance liquid chromatography coupled with mass spectrometry (HPLC/ESI/MSⁿ) allowed the characterization of 12 compounds such as sugars, phenolics and flavonoids. Among polyphenols, the main peak was assigned to isorhamnetin-3-O-(2'',3''-O-di-rhamnose)-glucoside. The TPC and TFC in the dry extract were 67.85 mg of gallic acid equivalent per g/extract and 46.16 mg quercetin equivalent per g/extract, respectively. In the in vitro MTT assay, the extract showed no cytotoxicity and suppressed ROS levels in LPS-treated RAW 264.7 cells. Preclinical models in rats showed that a dose of 100 mg kg^-1 (p < 0.0001) in the ethanol model and doses of 100 mg kg^-1 (p < 0.5) and 200 mg kg^-1 (p < 0.01) in the indomethacin model reduced the gastric lesions. Also, the extract reduced the MPO, MDA, TNF-α and IL-1β levels and increased the GSH and IL-10 levels. The pre-treatment with the extract led to the upregulation of SOD and the downregulation of COX-2 by immunohistochemical analysis. It also showed a cytoprotective effect in the histopathological analysis and stimulated the restoration of the mucus content as observed in the periodic acid-Schiff analysis without modifying the pH, volume or total acidity of the gastric juice. Taken together, N. cochenillifera extract can be applied as a novel gastroprotective ingredient for food or pharmaceutical products.

Statins Are Associated with Improved Survival of Patients with Gastric Cancer: A Systematic Review and Meta-Analysis

Statins are associated with gastric cancer (GC) risk. The present study aimed to clarify the efficacy of statins on the overall survival (OS) benefits in patients with GC. Publications were retrieved from PubMed, Embase, and the Cochrane Library as of April 2022. Data from the eligible cohort, case-control studies, and randomized control trials (RCTs) were extracted for the meta-analysis. Hazard ratio (HR) and 95% confidence intervals (CI) were used to assess the association between statins users and OS in GC patients. Subgroup analysis was performed based on the study design (prospective vs. retrospective). A total of 6 studies encompassing 5693 GC patients were included. Statins added to the standard treatment prolonged the patient's OS outcome (HR (95% CI): 0.72 (0.53-0.97), p = 0.032; I ² = 88.0%, p _{heterogeneity}  < 0.001). A prospective study did not find any statistically significant difference in OS between statins users vs. nonstatin users (HR (95% CI): 0.92 (0.68-1.26), p = 0.614; I ² = 11.7%, p _{heterogeneity}  = 0.322), whereas the retrospective studies showed prolonged OS in statins users (HR (95% CI): 0.63 (0.42-0.961), p = 0.032; I ² = 94.6%, p _{heterogeneity}  < 0.001). Statin users had significantly improved OS compared to nonstatin users in GC treatment. This long-term survival benefit was only observed in the pooled analysis of retrospective studies but not in prospective studies.

Gastric Ulcer Healing Property of Bryophyllum pinnatum Leaf Extract in Chronic Model In Vivo and Gastroprotective Activity of Its Major Flavonoid

Gastric ulcer is a common disease that develops complications such as hemorrhages and perforations when not properly treated. Extended use of drugs in the treatment of this pathology can provoke many adverse effects. Therefore, finding medicinal plants with gastroprotective and mucosal healing properties has gained increasing interest. Bryophyllum pinnatum (Crassulaceae), popularly known in Brazil as “saião” or “coirama,” has been used to treat inflammatory disorders. It is rich in flavonoids, and quercetin 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside-Bp1 is its major compound. In this study, we aimed to investigate ulcer healing properties of B. pinnatum against an acetic acid–induced chronic ulcer model and the gastroprotective activity of Bp1 against gastric lesions induced by ethanol and indomethacin. Ultrafast liquid chromatography was used to quantify the main compounds (mg/g of the extract)—quercetin 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (33.12 ± 0.056), kaempferol 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (3.98 ± 0.049), and quercetin 3-O-α-L-rhamnopyranoside (4.26 ± 0.022) and showed good linearity, specificity, selectivity, precision, robustness, and accuracy. In vivo studies showed that treatment with the extract at 250 and 500 mg/kg stimulated the healing process in the gastric mucosa with significant ulceration index reduction, followed by improvement in the antioxidant defense system [increased glutathione (GSH) levels, decreased superoxide dismutase upregulation, and malondialdehyde (MDA) levels]. Moreover, the extract decreased interleukin-1β and tumor necrosis factor-a levels and myeloperoxidase (MPO) activity, increased interleukin 10 levels, showed a cytoprotective effect in histological analyzes and also downregulated the expression of cyclooxygenase-2 and NF-κB (p65). The pretreatment with Bp1 at a dose of 5 mg/kg reduced gastric lesions in the ethanol and indomethacin models, increased GSH, and decreased MDA levels. In addition, the pretreatment decreased MPO activity, interleukin-1β and tumor necrosis factor-α levels, while also showing a cytoprotective effect in histological analyzes. Our study suggests that treatment with B. pinnatum extract showed a higher inhibition percentage than pretreatment with the Bp1. This might in turn suggest that Bp1 has gastroprotective activity, but other compounds can act synergistically, potentiating its effect. We conclude that B. pinnatum leaf extract could be a new source of raw material rich in phenolic compounds to be applied in food or medicine.

Pharmacological inhibition of KDM5A for cancer treatment

Lysine-specific demethylase 5A (KDM5A, also named RBP2 or JARID1A) is a demethylase that can remove methyl groups from histones H3K4me1/2/3. It is aberrantly expressed in many cancers, where it impedes differentiation and contributes to cancer cell proliferation, cell metastasis and invasiveness, drug resistance, and is associated with poor prognosis. Pharmacological inhibition of KDM5A has been reported to significantly attenuate tumor progression in vitro and in vivo in a range of solid tumors and acute myeloid leukemia. This review will present the structural aspects of KDM5A, its role in carcinogenesis, a comparison of currently available approaches for screening KDM5A inhibitors, a classification of KDM5A inhibitors, and its potential as a drug target in cancer therapy.