POR overexpression induces tamoxifen-resistance in breast cancer through the STAT1/c-Myc pathway

Breast cancer is the most common cancer in women worldwide. Although tamoxifen (TAM), a selective estrogen receptor (ER) modulator, is widely used to treat ER-positive breast cancers, resistance to TAM remains a major clinical problem. NADPH-dependent cytochrome P450 reductase (POR) is known to participate in drug metabolism and steroid metabolism. Recent studies showed that high POR expression was correlated with poor outcomes in triple-negative breast cancer (TNBC), and POR might be a prognostic biomarker in TNBC. However, the role of POR in TAM resistance is still elusive. In this study, we found that high POR expression was associated with poor prognosis of ER-positive and TAM-treated breast cancer patients. In addition, COX analysis showed that POR expression was an independent prognostic biomarker for ER-positive as well as TAM-treated breast cancer patients. Furthermore, our results suggested that POR overexpression promoted TAM resistance by activating the STAT1/c-Myc pathway in ER-positive breast cancer cells. Immunohistochemical analysis showed that high POR/STAT1 expression was correlated with poor prognosis in TAM-treated breast cancer patients. Notably, combined treatment with TAM and a specific STAT1 inhibitor Fludarabine was more effective for inhibiting TAM-resistant breast cancer cells. Altogether, our findings suggested that POR overexpression induced TAM resistance through STAT1/c-Myc pathway and might serve as an independent prognostic biomarker in TAM-treated breast cancer patients. Combining TAM and STAT1 inhibitors might be an effective strategy for treating POR-induced TAM-resistant breast cancer.

Immune Checkpoint Inhibitors and Opioids in Patients with Solid Tumours: Is Their Association Safe? A Systematic Literature Review

BACKGROUND

Immune checkpoint inhibitors (ICIs) represent one of the most effective treatments for patients with cancer. As their activity relies on host immune system reactivity, the role of concomitant medications such as corticosteroids and antibiotics has been extensively evaluated. Preclinical data suggest that opioids may influence the immune system.

METHODS

a systematic literature revision was performed using specific keywords on the major search engines. Two authors analysed all the studies and provided a selection of the following inclusion and exclusion criteria, respectively: 1. data collection of patients older than 18 years old affected by solid tumours; 2. description of ICIs efficacy in terms of PFS, OS, TTF, and ORR; 3. concomitant ICIs-opioids treatment and 1. language different from English; 2. not pertinent analyses.

RESULTS

523 studies were analysed, and 13 were selected and included in our series. A possible negative interaction between oral opioids and ICIs efficacy was observed. Most evidence was retrospective, and studies were heterogeneous.

CONCLUSIONS

Even if oral opioids seem to impact negatively on ICIs efficacy in cancer patients, to date there is not sufficient evidence to avoid their prescription in this population.

Incidence of Delirium With Different Oral Opioids in Previously Opioid-Naive Patients

Background: Opioids are known to induce delirium, but few studies have closely investigated differences in incidence of delirium among different opioids. Objectives: To determine whether there is a clinically significant difference in the incidence of delirium between oral opioids in previously opioid-naive patients. Methods: Subjects were 259 opioid-naive in-patients with cancer who were started on morphine sulfate, oxycodone hydrochloride, or tapentadol hydrochloride extended-release tablets at our hospital between August 1, 2014, and September 30, 2018. The incidence of delirium during the first week of treatment was compared between the drugs. Results: The incidence of delirium was 4.8% (n = 83) for morphine sulfate, 6.9% (n = 131) for oxycodone hydrochloride, and 6.7% (n = 45) for tapentadol hydrochloride. The incidence did not significantly differ between oxycodone hydrochloride (OR = .69, 95% CI = .20–2.30, P [Fisher’s exact test] = .77) or tapentadol hydrochloride (OR = .71, 95% CI = .15–3.32, P [Fisher’s exact test] = .70) and morphine sulfate (reference group). Moreover, the incidence did not significantly differ between tapentadol hydrochloride (OR = 1.03, 95% CI = .27–3.00, P [Fisher’s exact test] = 1.00) and oxycodone hydrochloride (reference group). Conclusion: The incidence of delirium in previously opioid-naive patients did not differ significantly among morphine sulfate, oxycodone hydrochloride, and tapentadol hydrochloride extended-release tablets, suggesting similar risk of delirium in opioid-naive patients among these oral opioids.

Practice Patterns of Medications for Patients With Malignant Bowel Obstruction Using a Nationwide Claims Database and the Association Between Treatment Outcomes and Concomitant Use of H2-Blockers/Proton Pump Inhibitors and Corticosteroids With Octreotide

CONTEXT

Malignant bowel obstruction impairs the quality of life in patients with advanced cancer. Octreotide, acid-suppressing medications such as H₂-receptor antagonists (H₂-blockers) and proton pump inhibitors (PPIs), and corticosteroids are often used in combination for symptom control.

OBJECTIVES

We evaluated the practice patterns of medications for patients hospitalized with malignant bowel obstruction using a large claims database in Japan. In addition, we explored the association of adding H₂-blockers/PPIs or corticosteroids to octreotide on treatment outcomes.

METHODS

We analyzed data from a nationwide medical claims database from April 2010 to March 2015 containing 975,000 patients. We included all adult inpatients with cancer who used octreotide 300 μg/day or more and summarized each patient's medication use. We also assessed whether concomitant use of H₂-blockers/PPIs or corticosteroids was associated with the number of days of nasogastric tube (NGT) insertion; logistic regression was used to adjust the patients' baseline factors.

RESULTS

We included 3090 patients; octreotide alone was used in 1649 (53%) cases. A combination of octreotide and H₂-blockers or PPIs was used in 419 and 337 cases (14% and 11%), respectively; a combination of octreotide and corticosteroids was used in 374 cases (12%). Of the 1595 patients who underwent NGT insertion, those using corticosteroids with octreotide had a higher odds ratio of NGT removal within four days of insertion (adjusted odds ratio = 1.16; 95% CI = 1.08-1.23).

CONCLUSION

Octreotide alone was used in the majority of patients, and the concomitant use of corticosteroids was more likely to be associated with early NGT removal.

Potential drug-drug interactions in inpatients treated at the Internal Medicine ward of Tikur Anbessa Specialized Hospital

PURPOSE

Although the concomitant use of multiple drugs often increases therapeutic effectiveness, certain combinations result in unwanted drug-drug interactions (DDIs). Most interactions go unnoticed by physicians due to the absence of new clinical signs and symptoms, and because they often produce a worsening of already existing symptoms. Quantification of the occurrence of the potential DDIs is essential to prevent the harmful effects associated with interactions. This study was launched to assess the prevalence of potential DDIs in the Internal Medicine ward of Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia.

PATIENTS AND METHODS

Cross-sectional data were gathered from the medical charts of 252 randomly selected patients who were admitted to the Internal Medicine ward during August 23 to October 23, 2013, and exposed to at least two concomitant drugs. Potential DDIs were identified using Medscape Drug Interaction Checker. The data were analyzed using SPSS software. Logistic regression analysis was used to determine the presence of association between variables and p-value <0.05 was considered statistically significant.

RESULTS

At least one potential DDI was found in 78.2% of the patients. The mean number of potential interactions per patient was 3.7±3.4. Out of the 719 potential interactions identified, 49.8% were pharmacokinetic type, 44.6% were pharmacodynamic and the remaining 5.6% were unknown mechanisms. Major potential DDIs accounted for 13.1% of the whole interactions; 53.5% were moderate interactions; and the remaining 33.4% were minor interactions. Ceftriaxone, cimetidine and heparin were the three most involved drugs in major potential interactions. Prescription of five or more concomitant drugs was associated with high risk of encountering potential DDIs.

CONCLUSION

The findings of this study showed that the prevalence of potential DDIs among inpatients was high. Pharmacists should closely review drugs prescribed for patients and avoid dispensing combinations of drugs that may have serious DDIs.

Supportive care in patients with advanced non-small-cell lung cancer

The present study describes supportive care (SC) in patients with advanced non-small-cell lung cancer (NSCLC), evaluating whether it is affected by concomitant chemotherapy, patient's performance status (PS) and age. Data of patients enrolled in three randomised trials of first-line chemotherapy, conducted between 1996 and 2001, were pooled. The analysis was limited to the first three cycles of treatment. Supportive care data were available for 1185 out of 1312 (90%) enrolled patients. Gastrointestinal drugs (45.7%), corticosteroids (33.4%) and analgesics (23.8%) were the most frequently observed categories. The mean number of drugs per patient was 2.43; 538 patients (45.4%) assumed three or more supportive drugs. Vinorelbine does not produce substantial variations in the SC pattern, while cisplatin-based treatment requires an overall higher number of supportive drugs, with higher use of antiemetics (41 vs 27%) and antianaemics (10 vs 4%). Patients with worse PS are more exposed to corticosteroids (42 vs 30%). Elderly patients require drugs against concomitant diseases significantly more than adults (20 vs 7%) and are less frequently exposed to antiemetics (12 vs 27%). In conclusion, polypharmacotherapy is a relevant issue in patients with advanced NSCLC. Chemotherapy does not remarkably affect the pattern of SC, except for some drugs against side effects. Elderly patients assume more drugs for concomitant diseases and receive less antiemetics than adults.