PD-1/PD-L1 Checkpoints and Resveratrol: A Controversial New Way for a Therapeutic Strategy

Resveratrol contributes to NK cell-mediated breast cancer cytotoxicity by upregulating ULBP2 through miR-17-5p downmodulation and activation of MINK1/JNK/c-Jun signaling

BACKGROUNDS

Natural killer (NK) cell mediated cytotoxicity is a crucial form of anti-cancer immune response. Natural killer group 2 member D (NKG2D) is a prominent activating receptor of NK cell. UL16-binding protein 2 (ULBP2), always expressed or elevated on cancer cells, functions as a key NKG2D ligand. ULBP2-NKG2D ligation initiates NK cell activation and subsequent targeted elimination of cancer cells. Enhanced expression of ULBP2 on cancer cells leads to more efficient elimination of these cells by NK cells. Resveratrol (RES) is known for its multiple health benefits, while current understanding of its role in regulating cancer immunogenicity remains limited. This study aims to investigate how RES affects the expression of ULBP2 and the sensitivity of breast cancer (BC) cells to NK cell cytotoxicity, along with the underlying mechanisms.

METHODS

The effects of RES on ULBP2 expression were detected with qRT-PCR, western blot, flow cytometry analysis and immunohistochemistry. The effects of RES on sensitivity of BC cells to NK cell cytotoxicity were evaluated in vitro and in vivo. The target gene of miR-17-5p were predicted with different algorithms from five databases and further confirmed with dual-luciferase reporter assay. Overexpression and knockdown experiments of miR-17-5p and MINK1 were conducted to investigate their roles in regulating ULBP2 expression and subsequent JNK/c-Jun activation. The JNK inhibitor sp600125 was utilized to elucidate the specific role of JNK in modulating ULBP2 expression.

RESULTS

RES increased ULBP2 expression on BC cells, thereby augmenting their vulnerability to NK cell-mediated cytotoxicity both in vitro and in vivo. RES administration led to a reduction in cellular miR-17-5p level. MiR-17-5p negatively regulated ULBP2 expression. Specifically, miR-17-5p directly targeted MINK1, leading to its suppression. MINK1 played a role in facilitating the activation of JNK and its downstream effector, c-Jun. Furthermore, treatment with sp600125, a JNK inhibitor, resulted in the suppression of ULBP2 expression.

CONCLUSIONS：

RES potentiates ULBP2-mediated immune eradication of BC cells by NK cells through the downregulation of miR-17-5p and concurrent activation of the MINK1/JNK/c-Jun cascade. This finding identifies RES as a potentially effective therapeutic agent for inhibiting BC progression and optimizing NK cell-based cancer immunotherapy.

Progress in personalized immunotherapy for patients with brain metastasis

Brain metastasis leads to poor outcomes and CNS injury, significantly reducing quality of life and survival rates. Advances in understanding the tumor immune microenvironment have revealed the promise of immunotherapies, which, alongside surgery, chemotherapy, and radiation, offer improved survival for some patients. However, resistance to immunotherapy remains a critical challenge. This review explores the immune landscape of brain metastases, current therapies, clinical trials, and the need for personalized, biomarker-driven approaches to optimize outcomes.

Polyphenols as Immunomodulators and Epigenetic Modulators: An Analysis of Their Role in the Treatment and Prevention of Breast Cancer

Breast cancer poses a substantial health challenge for women globally. Recently, there has been a notable increase in scholarly attention regarding polyphenols, primarily attributed to not only the adverse effects associated with conventional treatments but also their immune-preventive impacts. Polyphenols, nature-derived substances present in vegetation, including fruits and vegetables, have received considerable attention in various fields of science due to their probable wellness merits, particularly in the treatment and hindrance of cancer. This review focuses on the immunomodulatory effects of polyphenols in breast cancer, emphasizing their capacity to influence the reaction of adaptive and innate immune cells within the tumor-associated environment. Polyphenols are implicated in the modulation of inflammation, the enhancement of antioxidant defenses, the promotion of epigenetic modifications, and the support of immune functions. Additionally, these compounds have been shown to influence the activity of critical immune cells, including macrophages and T cells. By targeting pathways involved in immune evasion, polyphenols may augment the capacity of the defensive system to detect and eliminate tumors. The findings suggest that incorporating polyphenol-rich foods into the diet could offer a promising, collaborative (integrative) approach to classical breast cancer remedial procedures by regulating how the defense mechanism interacts with the disease.

The Impact of Proton Pump Inhibitors on the Efficacy of Immune Checkpoint Inhibitor Combinations in Patients with HBV-Associated Advanced Hepatocellular Carcinoma

Purpose

There is limited research on whether Proton Pump Inhibitors (PPIs) will affect the efficacy of immune checkpoint inhibitors (ICIs) in treating hepatocellular carcinoma (HCC).This study aimed to determine whether PPIs affect the survival outcomes of patients with HBV-associated advanced HCC receiving combination therapy based on ICIs.

Methods

We retrospectively analyzed patients with hepatitis B virus (HBV)-associated advanced HCC who underwent ICIs combination therapy from January 1, 2020, to December 30, 2022. Patients were stratified into PPI and non-PPI groups based on whether they received PPI treatment within 30 days before or after ICIs therapy. Patients' survival and the risk of PPI-associated mortality was assessed. Adverse events were also evaluated.

Results

A total of 183 patients with HBV-associated HCC treated with ICI combination therapy were included. The median survival time (12.5 months vs 13.7 months, P = 0.285) and incidence of adverse events (P = 0.729) did not significantly differ between the PPI and non-PPI groups. Even after propensity score matching, the difference in median overall survival (OS) between the two groups was not significant (10.7 months vs 11.4 months; P = 0.596) and the patient's OS is not significantly related to the dosage of PPI application (P > 0.05).However, according to our subgroup analysis, among HCC patients with a serum HBV DNA concentration ≥ 200 IU/mL, the use of PPIs significantly increased the risk of mortality in patients receiving ICI combination therapy (P = 0.024).

Conclusion

PPIs do not notably influence the survival prognosis of patients receiving ICI combination therapy for HBV-associated advanced HCC. However, among patients with high levels of HBV DNA, PPIs increase the risk of mortality. Therefore, antiviral therapy should be intensified in the patients with HBVDNA > 200 IU/mL. Additionally, PPIs do not impact the incidence of adverse reactions in these patients.

The Putative Effects of Neoadjuvant Chemotherapy on the Immune System of Advanced Epithelial Ovarian Carcinoma

The epithelial ovarian carcinoma (EOC) is one of leading causes of cancer-related mortality in females. For some patients, complete resection cannot be achieved, thus neoadjuvant chemotherapy (NACT) following interval debulking surgery (IDS) could be an alternative choice. In general-held belief, cytotoxic chemotherapy is assumed to be immunosuppressive, because of its toxicity to dividing cells in the bone marrow and peripheral lymphoid tissues. However, increasing evidence highlighted that the anticancer activity of chemotherapy may also be related to its ability to act as an immune modulator. NACT not only changed the morphology of cancer cells, but also changed the transcriptomic and genomic profile of EOC, induced proliferation of cancer stem-like cells, gene mutation, and tumor-related adaptive immune response. This review will provide a comprehensive overview of recent studies evaluating the impact of NACT on cancer cells and immune system of advanced EOC and their relationship to clinical outcome. This information could help us understand the change of immune system during NACT, which might provide new strategies in future investigation of immuno-therapy for maintenance treatment of EOC.

A novel PD-1/PD-L1 pathway molecular typing-related signature for predicting prognosis and the tumor microenvironment in breast cancer

BACKGROUND

Currently, the development of breast cancer immunotherapy based on the PD-1/PD-L1 pathway is relatively slow, and the specific mechanism affecting the immunotherapy efficacy in breast cancer is still unclear.

METHODS

Weighted correlation network analysis (WGCNA) and the negative matrix factorization (NMF) were used to distinguish subtypes related to the PD-1/PD-L1 pathway in breast cancer. Then univariate Cox, least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression were used to construct the prognostic signature. A nomogram was established based on the signature. The relationship between the signature gene IFNG and breast cancer tumor microenvironment was analyzed.

RESULTS

Four PD-1/PD-L1 pathway-related subtypes were distinguished. A prognostic signature related to PD-1/PD-L1 pathway typing was constructed to evaluate breast cancer's clinical characteristics and tumor microenvironment. The nomogram based on the RiskScore could be used to accurately predict breast cancer patients' 1-year, 3-year, and 5-year survival probability. The expression of IFNG was positively correlated with CD8+ T cell infiltration in the breast cancer tumor microenvironment.

CONCLUSION

A prognostic signature is constructed based on the PD-1/PD-L1 pathway typing in breast cancer, which can guide the precise treatment of breast cancer. The signature gene IFNG is positively related to CD8+ T cell infiltration in breast cancer.

Characterization of Cell Death Induced by Imine Analogs of Trans-Resveratrol: Induction of Mitochondrial Dysfunction and Overproduction of Reactive Oxygen Species Leading to, or Not, Apoptosis without the Increase in the S-Phase of the Cell Cycle

Trans-resveratrol (RSV) is a non-flavonoid polyphenol (stilbene) with numerous biological activities, such as anti-tumor activities. However, RSV is rapidly metabolized, which limits its therapeutic use. The availability of RSV analogues with similar activities for use in vivo is therefore a major challenge. For this purpose, several isomeric analogues of RSV, aza-stilbenes (AZA-ST 1a–g), were synthesized, and their toxicities were characterized and compared to those of RSV on murine N2a neuronal cells using especially flow cytometric methods. All AZA-ST 1a–g have an inhibitory concentration 50 (IC50) between 11.3 and 25 µM when determined by the crystal violet assay, while that of RSV is 14.5 µM. This led to the characterization of AZA-ST 1a–g—induced cell death, compared to RSV, using three concentrations encompassing the IC50s (6.25, 12.5 and 25 µM). For AZA-ST 1a–g and RSV, an increase in plasma membrane permeability to propidium iodide was observed, and the proportion of cells with depolarized mitochondria measured with DiOC6(3) was increased. An overproduction of reactive oxygen species (ROS) was also observed on whole cells and at the mitochondrial level using dihydroethidium and MitoSox Red, respectively. However, only RSV induced a mode of cell death by apoptosis associated with a marked increase in the proportion of cells with condensed and/or fragmented nuclei (12.5 µM: 22 ± 9%; 25 µM: 80 ± 10%) identified after staining with Hoechst 33342 and which are characteristic of apoptotic cells. With AZA-ST, a slight but significant increase in the percentage of apoptotic cells was only detected with AZA-ST 1b (25 µM: 17 ± 1%) and AZA-ST 1d (25 µM: 26 ± 4%). Furthermore, only RSV induced significant cell cycle modifications associated with an increase in the percentage of cells in the S phase. Thus, AZA-ST 1a–g—induced cell death is characterized by an alteration of the plasma membrane, an induction of mitochondrial depolarization (loss of ΔΨm), and an overproduction of ROS, which may or may not result in a weak induction of apoptosis without modification of the distribution of the cells in the different phases of the cell cycle.

Protective effect of resveratrol against pembrolizumab-induced hepatotoxicity and neurotoxicity in male rats

The present study investigates the effects of resveratrol (RSV) on brain and liver tissues in rats with pembrolizumab (PEMB)-induced toxicity. Obtained for the study were 28 male Sprague-Dawley rats (3-4 months old) which were divided into four groups: Group 1: Control. Group 2: Administered PEMB at 5 mg/kg/day i.p. for a week. Group 3: Administered RSV orally at the dose of 20 mg/kg/day for 30 days by gavage. Group 4: Administered PEMB and RSV at 20 and 5 mg/kg/day RSV, respectively, for 30 days. The results of this study revealed that PEMB leads to a significant increase in thiobarbituric acid reactive substance (TBARS) levels and a significant decrease in glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD) activities, and glutathione (GSH) levels in the liver and brain tissues. The decreased SOD, CAT, GPx activities, and GSH levels increased significantly following RSV treatment in Group 4. The PEMB treatment showed histopathological alterations associated with strong positive cysteinyl aspartic acid-protease-3 (caspase-3) immunoreactivity, while RSV treatment reduced both the expression of caspase-3 protein and the histopathological changes. RSV administration prevents the biochemical, immunological, and histological alterations induced by PEMB. It can be suggested that the lower caspase-3 immunoreactivity in the PEMB + RSV group than in the PEMB group led to an inhibition of RSV on apoptosis.

B7 family protein glycosylation: Promising novel targets in tumor treatment

Cancer immunotherapy, including the inhibition of immune checkpoints, improves the tumor immune microenvironment and is an effective tool for cancer therapy. More effective and alternative inhibitory targets are critical for successful immune checkpoint blockade therapy. The interaction of the immunomodulatory ligand B7 family with corresponding receptors induces or inhibits T cell responses by sending co-stimulatory and co-inhibitory signals respectively. Blocking the glycosylation of the B7 family members PD-L1, PD-L2, B7-H3, and B7-H4 inhibited the self-stability and receptor binding of these immune checkpoint proteins, leading to immunosuppression and rapid tumor progression. Therefore, regulation of glycosylation may be the "golden key" to relieve tumor immunosuppression. The exploration of a more precise glycosylation regulation mechanism and glycan structure of B7 family proteins is conducive to the discovery and clinical application of antibodies and small molecule inhibitors.

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.

MDSCs might be "Achilles heel" for eradicating CSCs

During tumor initiation and progression, the complicated role of immune cells in the tumor immune microenvironment remains a concern. Myeloid-derived suppressor cells (MDSCs) are a group of immune cells that originate from the bone marrow and have immunosuppressive potency in various diseases, including cancer. In recent years, the key role of cancer stemness has received increasing attention in cancer development and therapy. Several studies have demonstrated the important regulatory relationship between MDSCs and cancer stem cells (CSCs). However, there is still no clear understanding regarding the complex interacting regulation of tumor malignancy, and current research progress is limited. In this review, we summarize the complicated role of MDSCs in the modulation of cancer stemness, evaluate the mechanism of the relationship between CSCs and MDSCs, and discuss potential strategies for eradicating CSCs with respect to MDSCs.

Look into my onco-forest - review of plant natural products with anticancer activity

Cancer is a multistage process that can be treated by numerous modalities including systemic treatment. About half of the molecules that have been approved in the last few decades count for plant derivatives. This review presents the application of tree/shrub-derived biologically active compounds as anticancer agents. Different parts of trees/shrubs - wood, bark, branches, roots, leaves, needles, fruits, flowers etc. - contain a wide variety of primary and secondary metabolites, which demonstrate anticancer properties. Special attention was paid to phenolics (phenolic acids and polyphenols, including flavonoids and non-flavonoids (tannins, lignans, stilbenes)), essential oils and their main constituents such as terpenes/terpenoids, phytosterols, alkaloids and many others. Anticancer properties of these compounds are mainly attributed to their strong antioxidant properties. In vitro experiments on various cancer cell lines revealed a cytotoxic effect of tree-derived extracts. Mechanisms of anticancer action of the extracts are also listed. Examples of drugs that successfully underwent clinical trials with well-established position in the guidelines created by oncological societies are provided. The review also focuses on directions for the future in the development of anticancer agents derived from trees/shrubs. Applying biologically active compounds derived from trees and shrubs as anticancer agents continuously seems a promising strategy in cancer systemic treatment.