The Impact of Nonsteroidal Anti-Inflammatory Drugs, Beta Blockers, and Metformin on the Efficacy of Anti-PD-1 Therapy in Advanced Melanoma

Clinical evidence for the prognostic impact of metformin in cancer patients treated with immune checkpoint inhibitors

BACKGROUND

Preclinical studies suggest that metformin might enhance the efficacy of immune checkpoint inhibitors (ICIs) and potentially influence the prognoses of cancer patients undergoing ICIs treatment. This study endeavors to assess the prognostic significance of metformin in cancer patients undergoing ICIs therapy, aiming to furnish evidence-based insights for clinical practice.

METHODS

A thorough literature search was conducted across electronic databases to encompass all potential records published before November 20th, 2023. A meta-analysis was executed utilizing Stata 17.0 to derive pooled hazard ratios (HRs) with 95% confidence intervals (CIs) for both overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 22 studies encompassing 9,011 patients met the inclusion criteria. Meta-analyses revealed a significant correlation between metformin use and poorer OS (HR, 1.13; 95 %CI, 1.04-1.23; P = 0.004) rather than PFS (HR, 1.04; 95 %CI, 0.96-1.14; P = 0.345) among cancer patients undergoing ICIs treatment. Subgroup analysis delineated that the concurrent administration of metformin and ICIs significantly associated with adverse prognoses in the European population (OS: HR, 1.23; 95 %CI, 1.10-1.39; P = 0.001; PFS: HR, 1.14; 95 %CI, 1.02-1.28; P = 0.024).

CONCLUSION

Based on current clinical evidence, concomitant metformin use does not appear to improve the prognostic outcomes for cancer patients undergoing ICIs therapy and may potentially correlate with inferior prognoses. Further studies are imperative to comprehensively elucidate the impact of metformin within the realm of ICIs therapy.

Impact of metformin on melanoma: a meta-analysis and systematic review

Background

There is evidence of a modest reduction in skin cancer risk among metformin users. However, no studies have further examined the effects of metformin on melanoma survival and safety outcomes. This study aimed to quantitatively summarize any influence of metformin on the overall survival (OS) and immune-related adverse effects (irAEs) in melanoma patients.

Methods

Selection criteria: The inclusion criteria were designed based on the PICOS principles. Information sources: PubMed, EMBASE, Cochrane Library, and Web of Science were searched for relevant literature published from the inception of these databases until November 2023 using 'Melanoma' and 'Metformin' as keywords. Survival outcomes were OS, progression-free survival (PFS), recurrence-free survival (RFS), and mortality; the safety outcome was irAEs. Risk of bias and data Synthesis: The Cochrane tool for assessing the risk of bias in randomized trial 2 (RoB2) and methodological index for non-randomized studies (MINORS) were selected to assess the risk of bias. The Cochrane Q and I 2 statistics based on Stata 15.1 SE were used to test the heterogeneity among all studies. Funnel plot, Egger regression, and Begg tests were used to evaluate publication bias. The leave-one-out method was selected as the sensitivity analysis tool.

Results

A total of 12 studies were included, involving 111,036 melanoma patients. The pooled HR for OS was 0.64 (95% CI [0.42, 1.00], p = 0.004, I2 = 73.7%), HR for PFS was 0.89 (95% CI [0.70, 1.12], p = 0.163, I2 = 41.4%), HR for RFS was 0.62 (95% CI [0.26, 1.48], p = 0.085, I2 = 66.3%), and HR for mortality was 0.53 (95% CI [0.46, 0.63], p = 0.775, I2 = 0.0%). There was no significant difference in irAEs incidence (OR = 1.01; 95% CI [0.42, 2.41]; p = 0.642) between metformin and no metformin groups.

Discussion

The improvement in overall survival of melanoma patients with metformin may indirectly result from its diverse biological targets and beneficial effects on multiple systemic diseases. While we could not demonstrate a specific improvement in the survival of melanoma patients, the combined benefits and safety of metformin for patients taking the drug are worthy of recognition.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024518182.

Impact of Non-steroidal Anti-inflammatory Drugs, Glucocorticoids, and Disease-Modifying Anti-Rheumatic Drugs on Cancer Response to Immune Checkpoint Inhibitor Therapy

Immune checkpoint inhibitor (ICI) therapy for advanced malignancies often leads to off-target adverse events. Rheumatic immune-related adverse events can often linger beyond the duration of ICI therapy and sometimes requires the use of immunomodulator therapy. A key question, therefore, is if the commonly used therapies affect cancer outcomes. In this review, the authors summarize the state of the data as it currently stands, taking into consideration the limitations of the various source studies. The most information is known about glucocorticoids, which appear to be harmful especially when used early and at high doses.

Prognostic and predictive value of non-steroidal anti-inflammatory drugs in the EORTC 1325/KEYNOTE-054 phase III trial of pembrolizumab versus placebo in resected high-risk stage III melanoma

BACKGROUND

Pain is common in patients with cancer. The World Health Organisation recommends paracetamol or non-steroidal anti-inflammatory drugs (NSAIDs) for mild pain and combined with other agents for moderate/severe pain. This study estimated associations of NSAIDs with recurrence-free survival (RFS), distant metastasis-free survival (DMFS) and the incidence of immune-related adverse events (irAEs) in high-risk patients with resected melanoma in the EORTC 1325/KEYNOTE-054 phase III clinical trial.

PATIENTS AND METHODS

Patients with AJCC7 stage IIIA, IIIB or IIIC resected melanoma were randomized to receive 200 mg of adjuvant pembrolizumab (N = 514) or placebo (N = 505) 3-weekly for one year or until recurrence. As previously reported, pembrolizumab prolonged RFS and DMFS. NSAID use was defined as administration between 7 days pre-randomization and starting treatment. Multivariable Cox and Fine and Gray models were used to estimate hazard ratios (HRs) for associations of NSAIDs with RFS, DMFS and irAEs.

RESULTS

Of 1019 patients randomized, 59 and 44 patients in the pembrolizumab and placebo arms, respectively, used NSAIDs. NSAIDs were not associated with RFS (HR 0.91, 95% CI 0.58-1.43) or DMFS in the pembrolizumab (HR 1.03, 95% CI 0.65-1.66) or placebo arms (for RFS, HR 0.76, 95% CI 0.48-1.20; for DMFS, HR 0.80, 95% CI 0.49-1.31). NSAIDs were associated with the incidence of irAEs in the placebo arm (HR 3.06, 95% CI 1.45-6.45) but not in the pembrolizumab arm (HR 0.94, 95% CI 0.58-1.53).

CONCLUSION

NSAIDs were not associated with efficacy outcomes nor the risk of irAEs in patients with resected high-risk stage III melanoma receiving adjuvant pembrolizumab.

Readily available drugs and other interventions to potentially improve the efficacy of immune checkpoint blockade in cancer

To improve the efficacy of immune checkpoint inhibitors (ICIs) for cancer treatment, various strategies, including combination therapies with repurposed drugs, are being explored. Several readily available interventions with potential to enhance programmed death 1 (PD-1) blockade have been identified. However, these interventions often remain overlooked due to the lack of financial incentives for their development, making them financial orphans. This review summarizes current knowledge regarding off-label drugs, supplements, and other readily available interventions that could improve the efficacy of PD-1 blockade. The summary of each intervention includes the proposed mechanism of action for combination with checkpoint inhibitors and data from animal and human studies. Additionally, we include summaries of common interventions to be avoided by patients on PD-1 blockade. Finally, we present approaches for conducting further studies in patients, with the aim of expediting the clinical development of these interventions. We strive to increase awareness of readily available combination therapies that may advance cancer immunotherapy and help patients today.

Predictive Factors in Metastatic Melanoma Treated with Immune Checkpoint Inhibitors: From Clinical Practice to Future Perspective

The introduction of immunotherapy revolutionized the treatment landscape in metastatic melanoma. Despite the impressive results associated with immune checkpoint inhibitors (ICIs), only a portion of patients obtain a response to this treatment. In this scenario, the research of predictive factors is fundamental to identify patients who may have a response and to exclude patients with a low possibility to respond. These factors can be host-associated, immune system activation-related, and tumor-related. Patient-related factors can vary from data obtained by medical history (performance status, age, sex, body mass index, concomitant medications, and comorbidities) to analysis of the gut microbiome from fecal samples. Tumor-related factors can reflect tumor burden (metastatic sites, lactate dehydrogenase, C-reactive protein, and circulating tumor DNA) or can derive from the analysis of tumor samples (driver mutations, tumor-infiltrating lymphocytes, and myeloid cells). Biomarkers evaluating the immune system activation, such as IFN-gamma gene expression profile and analysis of circulating immune cell subsets, have emerged in recent years as significantly correlated with response to ICIs. In this manuscript, we critically reviewed the most updated literature data on the landscape of predictive factors in metastatic melanoma treated with ICIs. We focus on the principal limits and potentiality of different methods, shedding light on the more promising biomarkers.

Repurposing drugs for solid tumor treatment: focus on immune checkpoint inhibitors

Cancer remains a significant global health challenge with limited treatment options beyond systemic therapies, such as chemotherapy, radiotherapy, and molecular targeted therapy. Immunotherapy has emerged as a promising therapeutic modality but the efficacy has plateaued, which therefore provides limited benefits to patients with cancer. Identification of more effective approaches to improve patient outcomes and extend survival are urgently needed. Drug repurposing has emerged as an attractive strategy for drug development and has recently garnered considerable interest. This review comprehensively analyses the efficacy of various repurposed drugs, such as transforming growth factor-beta (TGF-β) inhibitors, metformin, receptor activator of nuclear factor-κB ligand (RANKL) inhibitors, granulocyte macrophage colony-stimulating factor (GM-CSF), thymosin α1 (Tα1), aspirin, and bisphosphonate, in tumorigenesis with a specific focus on their impact on tumor immunology and immunotherapy. Additionally, we present a concise overview of the current preclinical and clinical studies investigating the potential therapeutic synergies achieved by combining these agents with immune checkpoint inhibitors.

Effect of concurrent beta-blocker use in patients receiving immune checkpoint inhibitors for advanced solid tumors

PURPOSE

Stress-induced adrenergic signaling can suppress the immune system. In animal models, pharmacological beta-blockade stimulates CD8 + T-cell activity and improves clinical activity of immune checkpoint blockade (ICB) in inhibiting tumor growth. Herein, we investigated the effect of BB on clinical outcomes of patients receiving ICB in advanced solid tumors.

METHODS

We retrospectively evaluated patients with solid tumors treated with ICB at our institution from January 1, 2011 to April 28, 2017. The primary clinical outcome was disease control. Secondary clinical outcomes were overall survival (OS), and duration of therapy (DoT). The primary predictor was use of BB. Association between disease control status and BB use was assessed in univariable and multivariable logistic regression. OS was calculated using hazard ratios of BB-recipient patients vs. BB non-recipient patients via Cox proportional hazards regression models. All tests were two-sided at a significance level of 0.05.

RESULTS

Of 339 identified patients receiving ICB, 109 (32%) also received BB. In covariate-adjusted analysis, odds of disease control were significantly higher among BB recipients compared to BB-non-recipients (2.79; [1.54-5.03]; P = 0.001). While we did not observe significant association of OS with the use of BB overall, significant association with better OS was observed for the urothelial carcinoma cohort (HR: 0.24; [0.09, 0.62]; P = 0.0031).

CONCLUSIONS

Concurrent use of BB may enhance the clinical activity of ICB and influence overall survival, particularly in patients with urothelial carcinoma. Our findings warrant further investigation to understand the interaction of beta adrenergic signaling and antitumor immune activity and explore a combination strategy.

Metformin plays an antitumor role by downregulating inhibitory cells and immune checkpoint molecules while activating protective immune responses in breast cancer

This study seeks to test the effect of metformin treatment on the outcomes of breast cancer in BALB/c mice bearing 4 T1 breast cancer cells. The survival rate and tumor size of mice were compared, as well as evaluation of the changes of immune cells in spleens and the microenvironment of tumors using flow cytometry and ELISA. Our results demonstrate that metformin prolongs mouse survival. A significant decrease in M2-like macrophages (F4/80⁺CD206⁺) was found in mice spleen treated with metformin. The treatment also inhibited monocytic myeloid-derived suppressor cells (M-MDSCs, CD11b⁺Gr-1⁺) and regulatory T cells (Tregs, CD4⁺CD25⁺Foxp3⁺). Metformin treatment resulted in an increase in the level of IFN-γ and a decrease in IL-10. Expression of the immune checkpoint molecule PD-1 on T cells was inhibited following treatment. Metformin enhances local antitumor activity in the tumor microenvironment, and our data supports the drug as a candidate for evaluation in the treatment of breast cancer.

Outcomes of beta blocker use in advanced hepatocellular carcinoma treated with immune checkpoint inhibitors

Background

In patients with cirrhosis, portal hypertension increases intestinal permeability, dysbiosis, and bacterial translocation, promoting an inflammatory state that can lead to the progression of liver disease and development of hepatocellular carcinoma (HCC). We aimed to investigate whether beta blockers (BBs), which can mediate portal hypertension, conferred survival benefits in patients treated with immune checkpoint inhibitors (ICIs).

Methods

We conducted a retrospective, observational study of 578 patients with unresectable HCC treated with ICI from 2017 to 2019 at 13 institutions across three continents. BB use was defined as exposure to BBs at any time during ICI therapy. The primary objective was to assess the association of BB exposure with overall survival (OS). Secondary objectives were to evaluate the association of BB use with progression-free survival (PFS) and objective response rate (ORR) according to RECIST 1.1 criteria.

Results

In our study cohort, 203 (35%) patients used BBs at any point during ICI therapy. Of these, 51% were taking a nonselective BB. BB use was not significantly correlated with OS (hazard ratio [HR] 1.12, 95% CI 0.9-1.39, P = 0.298), PFS (HR 1.02, 95% CI 0.83-1.26, P = 0.844) or ORR (odds ratio [OR] 0.84, 95% CI 0.54-1.31, P = 0.451) in univariate or multivariate analyses. BB use was also not associated with incidence of adverse events (OR 1.38, 95% CI 0.96-1.97, P = 0.079). Specifically, nonselective BB use was not correlated with OS (HR 0.94, 95% CI 0.66-1.33, P = 0.721), PFS (HR 0.92, 0.66-1.29, P = 0.629), ORR (OR 1.20, 95% CI 0.58-2.49, P = 0.623), or rate of adverse events (OR 0.82, 95% CI 0.46-1.47, P = 0.510).

Conclusion

In this real-world population of patients with unresectable HCC treated with immunotherapy, BB use was not associated with OS, PFS or ORR.

Association of metformin use and survival in patients with cutaneous melanoma and diabetes

BACKGROUND

Metformin use has been associated with improved survival in patients with different types of cancer, but research regarding the effect of metformin on cutaneous melanoma (CM) survival is sparse and inconclusive.

OBJECTIVES

To investigate the association between metformin use and survival among patients with CM and diabetes.

METHODS

All adult patients with a primary invasive CM between 2007 and 2014 were identified in the Swedish Melanoma Registry and followed until death, or end of follow-up on 31 December 2017 in this population-based cohort study. Patients with both CM and type 2 diabetes mellitus were assessed further. Overall survival (OS) and melanoma-specific survival (MSS) were the primary endpoints. Cox proportional hazard models estimating crude and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were used comparing peridiagnostic use vs. nonuse of metformin. Dose response was evaluated based on defined daily doses.

RESULTS

Among a total of 23 507 patients, 1162 patients with CM and type 2 diabetes mellitus were included in the final cohort, with a median follow-up time of 4.1 years (interquartile range 2.4-6.1). Peridiagnostic metformin use was associated with a significantly decreased risk of death by any cause (HR 0.68, 95% CI 0.57-0.81). Cumulative pre- and postdiagnostic metformin use was also associated with improved OS: the HR for prediagnostic use was 0.90 (95% CI 0.86-0.95) for every 6 months of use and the HR for postdiagnostic use ranged from 0.98 (95% CI 0.97-0.98) for 0-6 months to 0.59 (0.49-0.70) for 24-30 months of use. No association was found for metformin use and MSS.

CONCLUSIONS

Metformin use was associated with improved OS in patients with CM and diabetes regardless of timing (pre-, post- or peridiagnostic use) and followed a dose-response pattern. However, further research regarding the underlying mechanisms is warranted.

The Association of Improved Overall Survival with NSAIDs in Non-Small Cell Lung Cancer Patients Receiving Immune Checkpoint Inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICI) are commonly used in the management of patients with advanced non-small cell lung cancer (NSCLC), but response is suboptimal. Preclinical data suggest ICI efficacy may be enhanced with concomitant nonsteroidal anti-inflammatory (NSAID) medications.

PATIENTS AND METHODS

In this retrospective study, the Veterans Health Administration Corporate Data Warehouse was queried for patients diagnosed with NSCLC and treated with ICI from 2010 to 2018. Concomitant NSAID use was defined as NSAID dispensation by a VA pharmacy within 90 days of the any ICI infusion. To mitigate immortal time bias, patients who started NSAIDs 60 or more days after ICI initiation were excluded from analysis. Survival was measured from start of ICI.

RESULTS

We identified 3634 patients with NSCLC receiving ICI; 2336 (64.3%) were exposed to concomitant NSAIDs. On multivariable analysis, NSAIDs were associated with better overall survival (HR = 0.90; 95% CI, 0.83-0.98; P = .010). When stratifying by NSAID type, diclofenac was the only NSAID with significant association with overall survival (HR = 0.75; 95% CI, 0.68-0.83; P < .001). Propensity score matching of the original cohort yielded 1251 patients per cohort balanced in characteristics. NSAIDs remained associated with improved overall survival (HR = 0.85; 95% CI, 0.78-0.92; P < .001).

CONCLUSION

This study of Veterans with NSCLC treated with ICI demonstrated that concomitant NSAIDs are associated with longer OS. This may indicate that NSAIDs can enhance ICI-induced antitumor immunity and should prospectively validated.

Brief Communication on the Impact of β-blockers on Outcomes in Patients Receiving Cancer Immunotherapy

Preclinical studies show that β-adrenergic activation suppresses the immune system and reduces the effectiveness of cancer immunotherapy. As a result, there is considerable interest in using β-blockers (BBs), a cheap and safe class of medication, in combination with immunotherapy to improve outcomes in cancer. This study is a systematic review and meta-analysis of clinical studies. A comprehensive literature search was performed up to May 2022. Studies were included if they reported hazard ratios (HRs) of overall survival (OS), all-cause mortality or progression-free survival (PFS) associated with BBs in patients with solid organ cancer treated with immunotherapy. Study-specific HRs and 95% confidence intervals were pooled in random effects meta-analyses. Nine studies involving over 6350 patients with melanoma, lung, renal, urothelial, or other solid cancers treated with a range of immunotherapies met the inclusion criteria. Across all studies combined, there was no association between concomitant BB use and OS (HR 0.99, 0.83-1.18) or PFS (HR 0.97, 0.89-1.05). In subgroup analyses, BB use made no difference to OS or PFS in melanoma (OS HR 0.66, 0.33-1.34; PFS HR 0.81, 0.62-1.05) or to OS in lung cancer (OS HR 1.00, 0.49-2.07). In summary, this study found no evidence that BBs enhance immunotherapy effectiveness.

Adding Cyclooxygenase Inhibitors to Immune Checkpoint Inhibitors Did Not Improve Outcomes in Metastatic Renal Cell Carcinoma

Modulating the cyclooxygenase 2 (COX-2) pathway has improved responses to immune checkpoint inhibitors (ICIs) in certain solid tumors, such as melanoma. Little is known about COX-2 inhibition in response to ICIs in metastatic renal cell carcinoma (mRCC). In this retrospective cohort study, we examined the effect of COX-2 inhibitors on the long-term outcomes of mRCC patients undergoing ICI therapies. Among 211 patients with mRCC, 23 patients were excluded due to loss to follow-up. Among 188 included patients, 120 patients received either an NSAID or aspirin for at least three weeks during ICI therapies. Clear cell histology was present in 96% of cases. The median overall survival (OS) was similar regardless of the COX inhibitor (COXi) (i.e., NSAID or aspirin) use (27 months for COXi vs. 33 months for no-COXi groups; p = 0.73). The no-COXi group showed a trend toward longer median progression-free survival (8 months for COXi vs. 13 months for no-COXi groups; p = 0.13). When looking specifically at NSAID use in a multivariate analysis, NSAID use was associated with a higher risk of progression (HR = 1.52 [95% CI, 1.04–2.22]) and death (HR = 1.60 [95% CI, 1.02–2.52]). In summary, COXis did not improve disease control or survival among patients with mRCC who were undergoing ICI therapies. Instead, the concurrent use of NSAIDs was associated with worse outcomes. Larger studies are needed to validate our observation.

Drug Repurposing to Enhance Antitumor Response to PD-1/PD-L1 Immune Checkpoint Inhibitors

Monoclonal antibodies targeting the PD-1/PD-L1 immune checkpoint have considerably improved the treatment of some cancers, but novel drugs, new combinations, and treatment modalities are needed to reinvigorate immunosurveillance in immune-refractory tumors. An option to elicit antitumor immunity against cancer consists of using approved and marketed drugs known for their capacity to modulate the expression and functioning of the PD-1/PD-L1 checkpoint. Here, we have reviewed several types of drugs known to alter the checkpoint, either directly via the blockade of PD-L1 or indirectly via an action on upstream effectors (such as STAT3) to suppress PD-L1 transcription or to induce its proteasomal degradation. Specifically, the repositioning of the approved drugs liothyronine, azelnidipine (and related dihydropyridine calcium channel blockers), niclosamide, albendazole/flubendazole, and a few other modulators of the PD-1/PD-L1 checkpoint (repaglinide, pimozide, fenofibrate, lonazolac, propranolol) is presented. Their capacity to bind to PD-L1 or to repress its expression and function offer novel perspectives for combination with PD-1 targeted biotherapeutics. These known and affordable drugs could be useful to improve the therapy of cancer.

Effect of Concomitant Use of Analgesics on Prognosis in Patients Treated With Immune Checkpoint Inhibitors: A Systematic Review and Meta-Analysis

Background

Drug–drug interactions (DDIs) pose new challenges beyond traditional pharmacodynamics in the context of optimizing the treatment options with immune checkpoint inhibitors (ICIs). To alleviate cancer-related pain, analgesics are of absolute vital importance as chronic medications used by cancer patients. However, the possible outcome of ICI treatment concomitant with analgesics remains unclear.

Methods

Original articles describing the possible influence of analgesics use on ICI treatment published before December 1, 2021 were retrieved from PubMed, Embase, and the Cochrane Library. Odds ratio (OR) with 95% confidence interval (CI) for objective response rate (ORR), hazard ratio (HR) with 95% CI for progression-free survival (PFS), and overall survival (OS) were calculated using the random-effects or fixed-effects model, and heterogeneity was assessed using the χ²-based Q-test. Publication bias was examined by funnel plot analysis.

Results

A total of 11 studies involving 4,404 patients were included. The pooled OR showed that opioid use decreased the response of opioid users to ICIs compared to non-opioid users (OR = 0.49, 95% CI = 0.37–0.65, p < 0.001). Compared to patients who did not receive opioids, opioid users had an increased risk of progression and mortality (HR = 1.61, 95% CI = 1.37–1.89, p < 0.001; HR = 1.67, 95% CI =1.30–2.14, p < 0.001, respectively). Furthermore, the concomitant use of non-steroidal anti-inflammatory drugs (NSAIDs) was not significantly associated with differences in ORR, PFS, and OS in patients treated with ICIs (OR = 1.40, 95% CI = 0.84–2.32, p = 0.190; HR = 0.90, 95% CI = 0.77–1.06, p = 0.186; HR = 0.90, 95% CI = 0.71–1.14, p = 0.384, respectively).

Conclusion

The concomitant use of opioids during ICI treatment has an adverse effect on patient prognosis, while the use of NSAIDs is not significantly associated with the prognosis in patients treated with ICIs.

Clinical and Biological Variables Influencing Outcome in Patients with Advanced Non-Small Cell Lung Cancer (NSCLC) Treated with Anti-PD-1/PD-L1 Antibodies: A Prospective Multicentre Study

Introduction: Immune checkpoint inhibitors (ICIs) have become the standard of treatment for patients with non-small cell lung cancer (NSCLC). However, there are still many uncertainties regarding the selection of the patient who could benefit more from this treatment. This study aims to evaluate the prognostic and predictive role of clinical and biological variables in unselected patients with advanced NSCLC candidates to receive ICIs. Methods: This is an observational and prospective study. The primary objective is the evaluation of the relationship between clinical and biological variables and the response to ICIs. Secondary objectives included: safety; assessment of the relationship between clinical and biological parameters/concomitant treatments and progression-free survival at 6 months and overall survival at 6 and 12 months. Nomograms to predict these outcomes have been generated. Results: A total of 166 patients were included. An association with response was found in the presence of the high immunohistochemical PD-L1 expression, squamous cell histotype, and early line of treatment, whereas a higher probability of progression was seen in the presence of anemia, high LDH values and neutrophil/lymphocyte ratio (NLR), pleural involvement, and thrombosis before treatment. The nomogram showed that anemia, PD-L1 expression, NLR, and LDH represented the most informative predictor as regards the three parameters of interest. Conclusions: In the era of personalized medicine, the results are useful for stratifying the patients and tailoring the treatments, considering both the histological findings and the clinical features of the patients.

Immune-checkpoint inhibitors: long-term implications of toxicity

The development of immune-checkpoint inhibitors (ICIs) has heralded a new era in cancer treatment, enabling the possibility of long-term survival in patients with metastatic disease, and providing new therapeutic indications in earlier-stage settings. As such, characterizing the long-term implications of receiving ICIs has grown in importance. An abundance of evidence exists describing the acute clinical toxicities of these agents, although chronic effects have not been as well catalogued. Nonetheless, emerging evidence indicates that persistent toxicities might be more common than initially suggested. While generally low-grade, these chronic sequelae can affect the endocrine, rheumatological, pulmonary, neurological and other organ systems. Fatal toxicities also comprise a diverse set of clinical manifestations and can occur in 0.4-1.2% of patients. This risk is a particularly relevant consideration in light of the possibility of long-term survival. Finally, the effects of immune-checkpoint blockade on a diverse range of immune processes, including atherosclerosis, heart failure, neuroinflammation, obesity and hypertension, have not been characterized but remain an important area of research with potential relevance to cancer survivors. In this Review, we describe the current evidence for chronic immune toxicities and the long-term implications of these effects for patients receiving ICIs.

Recent advances in primary resistance mechanisms against immune checkpoint inhibitors

PURPOSE OF REVIEW

The resistance of immune checkpoint inhibitors (ICIs) has become an obstacle to further improve the survival of patients with advanced cancer. This review provides an overview of recent advances in primary resistance mechanisms of ICIs.

RECENT FINDINGS

With the improvement of study approach, new characteristics and trends have emerged in the classification of tumor immune subtypes. The effects of germline genetic on tumor microenvironment and the efficacy of immunotherapy have been further studied. Exosomal programmed death-ligand 1 (PD-L1) is an increasing focus of research in primary resistance mechanisms of ICIs. In addition to antibiotics and steroids, the influence of other concomitant medications on the efficacy of ICIs has recently gained more attention.

SUMMARY

Exploring the resistance mechanisms of ICIs is one of the great challenges in the field of tumor immunotherapy. Continued work to understand the resistance mechanism of ICIs is ongoing.

Comprehensive Statistical Exploration of Prognostic (Bio-)Markers for Responses to Immune Checkpoint Inhibitor in Patients with Non-Small Cell Lung Cancer

Simple Summary

Metastatic non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs) may suffer from heavy side effects, and not all patients benefit from the treatment. Therefore, it is crucial to gain knowledge about possible (bio-)markers for response to ICIs. We used retrospective data acquired from NSCLC patients treated with ICIs in first- or further-line therapy settings, including 16 possible markers. We conducted a comprehensive statistical analysis study to find markers for response to treatment, assessed the robustness of our results, and discussed often encountered statistical pitfalls. Our study yielded hypotheses for various predictive and prognostic (bio-)markers for response to ICIs in NSCLC patients. In particular, we found that high basophil counts may be predictive for treatment response in patients in further-line therapy settings.

Abstract

Metastatic non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs) may suffer from heavy side effects and not all patients benefit from the treatment. We conducted a comprehensive statistical analysis to identify promising (bio-)markers for treatment response. We analyzed retrospective data from NSCLC patients treated with ICIs in first- or further-line therapy settings at the University Hospital Zurich. We investigated 16 possible prognostic markers with respect to overall survival, tumor size reduction, and the development of an immune-related adverse event (irAE) and assessed the robustness of our results. For the further-line patient group, the most significant result was that increased basophil counts were associated with increased odds of tumor size reduction within three months and with the development of an irAE. For the first-line patient group, the most significant results were that increased lymphocyte counts, the histology of adenocarcinoma, and the intake of non-steroidal anti-rheumatic drugs (NSAR) were associated with decreased hazards of dying. Our study yielded new hypotheses for predictive (bio-)markers for response to ICIs in NSCLC patients. The possibly beneficial role of high basophil counts is a particularly interesting finding. Our results should be tested on independent data in a prospective fashion.

Prognostic Value of Baseline Medications Plus Neutrophil-to-Lymphocyte Ratio in the Effectiveness of Nivolumab and Pembrolizumab in Patients With Advanced Non-Small-Cell Lung Cancer: A Retrospective Study

Background

Nivolumab and pembrolizumab are the standard treatments for patients with advanced non-small-cell lung cancer (NSCLC). While there are reports on several inflammatory indices and the prognosis of patients with cancer, no study has combined baseline medication with the neutrophil-to-lymphocyte ratio (NLR) to predict clinical outcomes. This study investigated the efficacy of baseline medications plus NLR to predict the effectiveness of nivolumab and pembrolizumab in a real-world clinical setting.

Methods

We conducted a single-center retrospective observational study of consecutive patients with advanced NSCLC who received nivolumab or pembrolizumab as first-line, second-line, or beyond treatment between December 2015 and November 2018 at the National Cancer Center Hospital in Japan. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. The drug-based prognostic score for baseline medications plus NLR was weighed based on the regression β coefficients. The multivariable Cox proportional hazard model was used to assess the association between the prognostic score-stratified groups and survival outcomes.

Results

In total, 259 patients were evaluated in this study. A prognostic score calculated from the baseline medications plus NLR was used to categorize the patients into good (score 0), intermediate (scores 1–2), and poor (scores 3–6) -prognosis groups. The multivariable Cox proportional hazard model revealed a significant association between the poor-prognosis group and reduced OS. The hazard ratio of OS was 1.75 (95% confidence interval: 1.07–2.99; P = 0.031). In contrast, no association between these prognosis groups and PFS was observed.

Conclusions

The findings suggest that the baseline medications with nivolumab or pembrolizumab plus NLR could lead to progressively shorter survival outcomes in patients with advanced NSCLC and could be used as a prognostic index for poor outcomes. However, to ascertain the clinical application of these findings, these concomitant medications need further validation in a large-scale multicenter study.

NSAIDs: Old Acquaintance in the Pipeline for Cancer Treatment and Prevention─Structural Modulation, Mechanisms of Action, and Bright Future

The limitations of current chemotherapeutic drugs are still a major issue in cancer treatment. Thus, targeted multimodal therapeutic approaches need to be strategically developed to successfully control tumor growth and prevent metastatic burden. Inflammation has long been recognized as a hallmark of cancer and plays a key role in the tumorigenesis and progression of the disease. Several epidemiological, clinical, and preclinical studies have shown that traditional nonsteroidal anti-inflammatory drugs (NSAIDs) exhibit anticancer activities. This Perspective reports the most recent outcomes for the treatment and prevention of different types of cancers for several NSAIDs alone or in combination with current chemotherapeutic drugs. Furthermore, an extensive review of the most promising structural modifications is reported, such as phospho, H₂S, and NO releasing-, selenium-, metal complex-, and natural product-NSAIDs, among others. We also provide a perspective about the new strategies used to obtain more efficient NSAID- or NSAID derivative- formulations for targeted delivery.

Directing T-Cell Immune Responses for Cancer Vaccination and Immunotherapy

Cancer vaccination and immunotherapy revolutionised the treatment of cancer, a result of decades of research into the immune system in health and disease. However, despite recent breakthroughs in treating otherwise terminal cancer, only a minority of patients respond to cancer immunotherapy and some cancers are largely refractive to immunotherapy treatment. This is due to numerous issues intrinsic to the tumour, its microenvironment, or the immune system. CD4+ and CD8+ αβ T-cells emerged as the primary effector cells of the anti-tumour immune response but their function in cancer patients is often compromised. This review details the mechanisms by which T-cell responses are hindered in the setting of cancer and refractive to immunotherapy, and details many of the approaches under investigation to direct T-cell function and improve the efficacy of cancer vaccination and immunotherapy.

Targeting of the tumor immune microenvironment by metformin

Stimulating antitumor immunity is an attractive idea for suppressing tumors. CD4 + and CD8 + T cells as well as natural killer cells (NK) are the primary antitumor immune cells in the tumor microenvironment (TME). In contrast to these cells, regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), cancer-associated fibroblasts (CAFs), and tumor-associated macrophages (TAMs) release several molecules to suppress antitumor immunity and stimulate cancer cell invasion and proliferation. Adjuvant treatment with certain nontoxic agents is interesting to boost antitumor immunity. Metformin, which is known as an antidiabetes drug, can modulate both antitumor and protumor immune cells within TME. It has the ability to induce the proliferation of CD8 + T lymphocytes and NK cells. On the other hand, metformin attenuates polarization toward TAMs, CAFs, and Tregs. Metformin also may stimulate the antitumor activity of immune system cells, while it interrupts the positive cross-talk and interactions between immunosuppressive cells and cancer cells. The purpose of this review is to explain the basic mechanisms for the interactions and communications between immunosuppressive, anti-tumoral, and cancer cells within TME. Next, we discuss the modulating effects of metformin on various cells and secretions in TME.

Anti-Inflammatory Drugs Remodel the Tumor Immune Environment to Enhance Immune Checkpoint Blockade Efficacy

Identifying strategies to improve the efficacy of immune checkpoint blockade (ICB) remains a major clinical need. Here, we show that therapeutically targeting the COX2/PGE2/EP2-4 pathway with widely used nonsteroidal and steroidal anti-inflammatory drugs synergized with ICB in mouse cancer models. We exploited a bilateral surgery model to distinguish responders from nonresponders shortly after treatment and identified acute IFNγ-driven transcriptional remodeling in responder mice, which was also associated with patient benefit to ICB. Monotherapy with COX2 inhibitors or EP2-4 PGE2 receptor antagonists rapidly induced this response program and, in combination with ICB, increased the intratumoral accumulation of effector T cells. Treatment of patient-derived tumor fragments from multiple cancer types revealed a similar shift in the tumor inflammatory environment to favor T-cell activation. Our findings establish the COX2/PGE2/EP2-4 axis as an independent immune checkpoint and a readily translatable strategy to rapidly switch the tumor inflammatory profile from cold to hot. SIGNIFICANCE: Through performing in-depth profiling of mice and human tumors, this study identifies mechanisms by which anti-inflammatory drugs rapidly alter the tumor immune landscape to enhance tumor immunogenicity and responses to immune checkpoint inhibitors.See related commentary by Melero et al., p. 2372.This article is highlighted in the In This Issue feature, p. 2355.

Dual Blockade of Lactate/GPR81 and PD-1/PD-L1 Pathways Enhances the Anti-Tumor Effects of Metformin

Metformin is a widely used antidiabetic drug for cancer prevention and treatment. However, the overproduction of lactic acid and its inefficiency in cancer therapy limit its application. Here, we demonstrate the synergistic effects of the lactate/GPR81 blockade (3-hydroxy-butyrate, 3-OBA) and metformin on inhibiting cancer cells growth in vitro. Simultaneously, this combination could inhibit glycolysis and OXPHOS metabolism, as well as inhibiting tumor growth and reducing serum lactate levels in tumor-bearing mice. Interestingly, we observed that this combination could enhance the functions of Jurkat cells in vitro and CD8+ T cells in vivo. In addition, considering that 3-OBA could recover the inhibitory effects of metformin on PD-1 expression, we further determined the dual blockade effects of PD-1/PD-L1 and lactate/GPR81 on the antitumor activity of metformin. Our results suggested that this dual blockade strategy could remarkably enhance the anti-tumor effects of metformin, or even lead to tumor regression. In conclusion, our study has proposed a novel and robust strategy for a future application of metformin in cancer treatment.

The effect of concomitant use of statins, NSAIDs, low-dose aspirin, metformin and beta-blockers on outcomes in patients receiving immune checkpoint inhibitors: a systematic review and meta-analysis

Immunotherapy shows promising therapeutic efficacy against various types of cancer, but most fail to respond. Preclinical studies have suggested that concomitant medications, such as statins, non-steroidal anti-inflammatory drugs (NSAIDs), aspirin, metformin and beta-blockers, might affect clinical outcomes if used with immune checkpoint inhibitors (ICIs), but their clinical roles are conflicting. This meta-analysis investigates the effect of these concomitant medications on outcomes in patients treated with ICIs. A search was conducted for all reports published until 31 March 2021 in PubMed, Web of Science, Cochrane Library, EMBASE and conference proceedings. Studies were included if they investigated the association between the concomitant use of these medications and progression-free survival (PFS) or overall survival (OS) during ICI treatment. A total of 3331 patients from 13 eligible studies were included. Among them, five articles on statins, six studies evaluating NSAIDs, five studies employing low-dose aspirin, eight studies on metformin and four articles on beta-blockers were included. The concomitant use of statins during ICI treatment was correlated with improved OS and PFS. Low-dose aspirin was associated with better PFS instead of OS. No significant association was demonstrated between the concurrent use of NSAIDs, beta-blockers and metformin and OS or PFS. The concomitant use of statins and low-dose aspirin during ICI treatment showed a positive impact on treatment outcomes. The concurrent use of NSAIDs, beta-blockers and metformin is not significantly associated with clinical benefits. The effect of these medications in different cancer patients treated with ICI is needed to be further validated.

In Vitro Effects of Selective COX and LOX Inhibitors and Their Combinations with Antineoplastic Drugs in the Mouse Melanoma Cell Line B16F10

The constitutive expression or overactivation of cyclooxygenase (COX) and lipoxygenase (LOX) enzymes results in aberrant metabolism of arachidonic acid and poor prognosis in melanoma. Our aim is to compare the in vitro effects of selective COX-1 (acetylsalicylic acid), COX-2 (meloxicam), 5-LOX (MK-886 and AA-861), 12-LOX (baicalein) and 15-LOX (PD-146176) inhibition in terms of proliferation (SRB assay), mitochondrial viability (MTT assay), caspase 3-7 activity (chemiluminescent assay), 2D antimigratory (scratch assay) and synthesis of eicosanoids (EIA) in the B16F10 cell line (single treatments). We also explore their combinatorial pharmacological space with dacarbazine and temozolomide (median effect method). Overall, our results with single treatments show a superior cytotoxic efficacy of selective LOX inhibitors over selective COX inhibitors against B16F10 cells. PD-146176 caused the strongest antiproliferation effect which was accompanied by cell cycle arrest in G₁ phase and an >50-fold increase in caspases 3/7 activity. When the selected inhibitors are combined with the antineoplastic drugs, only meloxicam provides clear synergy, with LOX inhibitors mostly antagonizing. These apparent contradictions between single and combination treatments, together with some paradoxical effects observed in the biosynthesis of eicosanoids after FLAP inhibition in short term incubations, warrant further mechanistical in vitro and in vivo scrutiny.

Clinical impact of probiotics on the efficacy of anti-PD-1 monotherapy in patients with nonsmall cell lung cancer: A multicenter retrospective survival analysis study with inverse probability of treatment weighting

The gastrointestinal microbiota was reported as an important factor for the response to cancer immunotherapy. Probiotics associated with gastrointestinal dysbiosis and bacterial richness may affect the efficacy of cancer immunotherapy drugs. However, the clinical impact of probiotics on the efficacy of cancer immunotherapy in patients with nonsmall cell lung cancer (NSCLC) is poorly understood. The outcomes of 294 patients with advanced or recurrent NSCLC who received antiprogrammed cell death-1 (PD-1) therapy (nivolumab or pembrolizumab monotherapy) at three medical centers in Japan were analyzed in our study. We used inverse probability of treatment weighting (IPTW) to minimize the bias arising from the patients' backgrounds. The IPTW-adjusted Kaplan-Meier curves showed that progression-free survival (nonuse vs use: hazard ratio [HR] [95% confidence interval {CI}] = 1.73 [1.42-2.11], log-rank test P = .0229), but not overall survival (nonuse vs use: HR [95%CI] = 1.40 [1.13-1.74], log-rank test P = .1835), was significantly longer in patients who received probiotics. Moreover, the IPTW-adjusted univariate analyses showed that nonuse or use of probiotics was significantly associated with disease control (nonuse vs use: odds ratio [OR] [95%CI] = 0.51 [0.35-0.74], P = .0004) and overall response (nonuse vs use: OR [95%CI] = 0.43 [0.29-0.63], P < .0001). In this multicenter and retrospective study, probiotics use was associated with favorable clinical outcomes in patients with advanced or recurrent NSCLC who received anti-PD-1 monotherapy. The findings should be validated in a future prospective study.

Effect of cyclooxygenase inhibitor use on immunotherapy efficacy in non-small cell lung cancer

BACKGROUND

A synergistic effect of cyclooxygenase inhibitors (COX-I) and immune checkpoint inhibitors (ICIs) has been suggested. However, the impact of COX-I on the efficacy of ICIs is unclear. Here, we aimed to evaluate the relationship between COX-I use and the efficacy of ICI in patients with non-small cell lung cancer (NSCLC).

METHODS

We retrospectively reviewed NSCLC patients who received ICI monotherapy. We defined COX-I use as regular use of COX-I other than low-dose aspirin during the initiation of ICIs to the first evaluation of efficacy. The efficacy of ICIs was evaluated with response rate (RR), disease control rate (DCR), progression free survival (PFS), and overall survival (OS). Differences in baseline characteristics by COX-I use were controlled by using an inverse probability of treatment weighting (IPW) adjusted analysis.

RESULTS

A total of 198 patients with NSCLC received ICIs; 128, 50, and 20 patients received nivolumab, pembrolizumab, and atezolizumab, respectively; there were 65 (32.8%) COX-I users. While there was no significant difference in RR (15.4% vs. 13.5%; p = 0.828), DCR (41.5% vs. 49.6%; p = 0.294), PFS (median, 2.69 vs. 3.68 months; 95% confidence intervals [CI], 1.77-5.19 vs. 2.20-4.60 months; p = 0.630), COX-I users had significantly shorter OS than non-COX-I users (median, 6.08 vs. 16.10 months; 95% CI: 3.78-11.66 vs. 9.49-19.68 months; p = 0.003). On IPW adjusted analysis, there was no significant difference in OS (median, 7.85 vs. 15.11 months; 95% CI: 5.03-14.92 vs. 9.49-19.32 months; p = 0.081).

CONCLUSIONS

There was no additional or negative impact of COX-I use on the efficacy of ICIs in NSCLC.

Pleiotropic Effects of Metformin on the Antitumor Efficiency of Immune Checkpoint Inhibitors

Cancer is an important threat to public health because of its high morbidity and mortality. In recent decades, immune checkpoint inhibitors (ICIs) have ushered a new therapeutic era in clinical oncology. The rapid development of immune checkpoint therapy is due to its inspiring clinical efficacy in a group of cancer types. Metformin, an effective agent for the management of type 2 diabetes mellitus (T2DM), has shown beneficial effects on cancer prevention and cancer treatment. Emerging studies have suggested that metformin in combination with ICI treatment could improve the anticancer effects of ICIs. Hence, we conducted a review to summarize the effects of metformin on ICI therapy. We also review the pleiotropic mechanisms of metformin combined with ICIs in cancer therapy, including its direct and indirect effects on the host immune system.

Effect of concomitant medications with immune-modulatory properties on the outcomes of patients with advanced cancer treated with immune checkpoint inhibitors: development and validation of a novel prognostic index

BACKGROUND

Concomitant medications are known to impact on clinical outcomes of patients treated with immune checkpoint inhibitors (ICIs). We aimed weighing the role of different concomitant baseline medications to create a drug-based prognostic score.

METHODS

We evaluated concomitant baseline medications at immunotherapy initiation for their impact on objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) in a single-institution cohort of patients with advanced cancer treated with ICIs (training cohort, N = 217), and a drug-based prognostic score with the drugs resulting significantly impacting the OS was computed. Secondly, we externally validated the score in a large multicenter external cohort (n = 1012).

RESULTS

In the training cohort (n = 217), the median age was 69 years (range: 32-89), and the primary tumours were non-small-cell lung cancer (70%), melanoma (14.7%), renal cell carcinoma (9.2%) and others (6%). Among baseline medications, corticosteroids (hazard ratio [HR] = 2.3; 95% confidence interval [CI]: 1.60-3.30), systemic antibiotics (HR = 2.07; 95% CI: 1.31-3.25) and proton-pump inhibitors (PPIs) (HR = 1.57; 95% CI: 1.13-2.18) were significantly associated with OS. The prognostic score was calculated using these three drug classes, defining good, intermediate and poor prognosis patients. Within the training cohort, OS (p < 0.0001), PFS (p < 0.0001) and ORR (p = 0.0297) were significantly distinguished by the score stratification. The prognostic value of the score was also demonstrated in terms of OS (p < 0.0001), PFS (p < 0.0001) and ORR (p = 0.0006) within the external cohort.

CONCLUSION

Cumulative exposure to corticosteroids, antibiotics and PPIs (three likely microbiota-modulating drugs) leads to progressively worse outcomes after ICI therapy. We propose a simple score that can help stratifying patients in routine practice and clinical trials of ICIs.

Integrated analysis of concomitant medications and oncological outcomes from PD-1/PD-L1 checkpoint inhibitors in clinical practice

Background

Concomitant medications, such as steroids, proton pump inhibitors (PPI) and antibiotics, might affect clinical outcomes with immune checkpoint inhibitors.

Methods

We conducted a multicenter observational retrospective study aimed at evaluating the impact of concomitant medications on clinical outcomes, by weighing their associations with baseline clinical characteristics (including performance status, burden of disease and body mass index) and the underlying causes for their prescription. This analysis included consecutive stage IV patients with cancer, who underwent treatment with single agent antiprogrammed death-1/programmed death ligand-1 (PD-1/PD-L1) with standard doses and schedules at the medical oncology departments of 20 Italian institutions. Each medication taken at the immunotherapy initiation was screened and collected into key categories as follows: corticosteroids, antibiotics, gastric acid suppressants (including proton pump inhibitors - PPIs), statins and other lipid-lowering agents, aspirin, anticoagulants, non-steroidal anti-inflammatory drugs (NSAIDs), ACE inhibitors/Angiotensin II receptor blockers, calcium antagonists, β-blockers, metformin and other oral antidiabetics, opioids.

Results

From June 2014 to March 2020, 1012 patients were included in the analysis. Primary tumors were: non-small cell lung cancer (52.2%), melanoma (26%), renal cell carcinoma (18.3%) and others (3.6%). Baseline statins (HR 1.60 (95% CI 1.14 to 2.25), p=0.0064), aspirin (HR 1.47 (95% CI 1.04 to 2.08, p=0.0267) and β-blockers (HR 1.76 (95% CI 1.16 to 2.69), p=0.0080) were confirmed to be independently related to an increased objective response rate. Patients receiving cancer-related steroids (HR 1.72 (95% CI 1.43 to 2.07), p<0.0001), prophylactic systemic antibiotics (HR 1.85 (95% CI 1.23 to 2.78), p=0.0030), prophylactic gastric acid suppressants (HR 1.29 (95% CI 1.09 to 1.53), p=0.0021), PPIs (HR 1.26 (95% CI 1.07 to 1.48), p=0.0050), anticoagulants (HR 1.43 (95% CI: 1.16 to 1.77), p=0.0007) and opioids (HR 1.71 (95% CI 1.28 to 2.28), p=0.0002) were confirmed to have a significantly higher risk of disease progression. Patients receiving cancer-related steroids (HR 2.16 (95% CI 1.76 to 2.65), p<0.0001), prophylactic systemic antibiotics (HR 1.93 (95% CI 1.25 to 2.98), p=0.0030), prophylactic gastric acid suppressants (HR 1.29 (95% CI 1.06 to 1.57), p=0.0091), PPI (HR 1.26 (95% CI 1.04 to 1.52), p=0.0172), anticoagulants (HR 1.45 (95% CI 1.14 to 1.84), p=0.0024) and opioids (HR 1.53 (95% CI 1.11 to 2.11), p=0.0098) were confirmed to have a significantly higher risk of death.

Conclusion

We confirmed the association between baseline steroids administered for cancer-related indication, systemic antibiotics, PPIs and worse clinical outcomes with PD-1/PD-L1 checkpoint inhibitors, which can be assumed to have immune-modulating detrimental effects.

Clinically feasible and prospective immunotherapeutic interventions in multidirectional comprehensive treatment of cancer

INTRODUCTION

The immune system is able to exert both tumor-destructive and tumor-protective functions. Immunotherapeutic technologies aim to enhance immune-based anti-tumor activity and (or) weaken tumor-protective immunity.

AREAS COVERED

Cancer vaccination, antibody (Ab)-mediated cytotoxicity, Ab-based checkpoint molecule inhibition, Ab-based immunostimulation, cytokine therapy, oncoviral therapy, drug-mediated immunostimulation, exovesicular therapy, anti-inflammatory therapy, neurohormonal immunorehabilitation, metabolic therapy, as well as adoptive cell immunotherapy, could be coherently used to synergize and amplify each other in achieving robust anti-cancer responses in cancer patients. Tumor-specific immunotherapy applied at early stages is capable of eliminating remaining tumor cells after surgery, thus preventing the development of minimal residual disease. Patients with advanced disease stages could benefit from combined immunotherapy, which would be aimed at providing tumor cell/mass dormancy. Traditional therapeutic anti-cancer interventions (chemoradiotherapy, hyperthermia, anti-hormonal therapy) could significantly enhance tumor sensitivity to anti-cancer immunotherapy. It is important that lower-dose (metronomic) chemotherapy regimens, which are well-tolerated by normal cells, could advance immune-mediated control over tumor growth.

EXPERT OPINION

We envisage that combined immunotherapy regimens in the context of traditional treatment could become the mainstream modality for treating cancers in all phases of the tumorigenesis. The effectiveness of the anti-cancer treatment could be monitored by the following blood parameters: C-reactive protein, lactate dehydrogenase, and neutrophil-to-lymphocyte ratio.

Impact of metformin on immunological markers: Implication in its anti-tumor mechanism

Metformin, an anti-hyperglycemic drug, has been known to have antitumor properties for around 15 years. Although there are a number of reports attributing the antitumor function of metformin to its impact on energy homeostasis and oxygen re-distribution in tumor microenvironment, detailed mechanisms remain largely unknown. In the past several years, there is an increasing number of publications indicating that metformin can affect various immunological components including lymphocytes, macrophages, cytokines and several key immunological molecules in both human and animal studies. These interesting results appear to be in line with emerging data that suggest associations between immune responses and energy homeostasis/oxygen re-distribution, which may explain effective impacts of metformin on immunotherapies against autoimmune diseases as well as cancers. This review article is to analyse and discuss recent development in the above areas with aim to justify metformin as a new adjuvant for immunotherapy against human cancers. We hope that our summary will help to optimize the application of metformin for various types of human cancers.