Cisplatin increases PD-L1 expression and optimizes immune check-point blockade in non-small cell lung cancer

Nonlinear association between PD-L1 expression levels and the risk of postoperative recurrence in non-small cell lung cancer

Accurate prediction of postoperative recurrence is important for optimizing the treatment strategies for non-small cell lung cancer (NSCLC). Previous studies identified the PD-L1 expression in NSCLC as a risk factor for postoperative recurrence. This study aimed to examine the contribution of PD-L1 expression to predicting postoperative recurrence using machine learning. The clinical data of 647 patients with NSCLC who underwent surgical resection were collected and stratified into training (80%), validation (10%), and testing (10%) datasets. Machine learning models were trained on the training data using clinical parameters including PD-L1 expression. The top-performing model was assessed on the test data using the SHAP analysis and partial dependence plots to quantify the contribution of the PD-L1 expression. Multivariate Cox proportional hazards model was used to validate the association between PD-L1 expression and postoperative recurrence. The random forest model demonstrated the highest predictive performance with the SHAP analysis, highlighting PD-L1 expression as an important feature, and the multivariate Cox analysis indicated a significant increase in the risk of postoperative recurrence with each increment in PD-L1 expression. These findings suggest that variations in PD-L1 expression may provide valuable information for clinical decision-making regarding lung cancer treatment strategies.

Impact of platinum-based chemotherapy on the tumor mutational burden and immune microenvironment in non-small cell lung cancer with postoperative recurrence

PURPOSE

To investigate the impact of platinum-based adjuvant chemotherapy on the immunotherapeutic biomarkers of postoperative recurrent tumors in non-small cell lung cancer (NSCLC).

METHODS

This study involved twenty-two cases of NSCLC, all of which underwent postoperative platinum-based chemotherapy, with matched surgical samples obtained from both their primary tumors (PTs) and recurrent tumors (RTs). Multiplex immunofluorescence was performed to assess the tumor proportion score (TPS) and immune cells (IC) on whole sections. Whole exon sequencing (WES) was conducted to investigate the tumor mutational burden (TMB) and tumor neoantigen burden (TNB).

RESULTS

Compared to paired PTs, RTs exhibited higher PD-L1 expression, along with a slightly elevated density of intratumoral PD-L1+ cells (p = 0.082) and an increased tumor proportion score (mean TPS: 40.51% vs. 28.56%, p = 0.046). Regarding IC infiltration, RTs generally demonstrated significantly lower CD8+  cytotoxic T lymphocyte (CTL) density (p = 0.011) and lower CD68+  macrophage density (p = 0.005), with a loss of tertiary lymphoid structure (TLS). The comparison between RTs and PTs revealed no significant differences in TMB (p = 0.795), whereas the count of TNB in RTs was notably increased compared to PTs (p = 0.033). Prognosis analysis indicated that a higher density of CD8+  CTLs in RTs was positively correlated with improved overall survival (OS).

CONCLUSIONS

In NSCLC patients with a history of postoperative platinum-based chemotherapy, the RTs demonstrated a trend towards increased PD-L1 expression and TMB/TNB, but a state of immunosuppression characterized by decreased ICs and loss of TLS, which may potentially impact the therapeutic benefits of immunotherapy.

Centipeda minima and 6-O-angeloylplenolin enhance the efficacy of immune checkpoint inhibitors in non-small cell lung cancer

BACKGROUND

Chemotherapeutic agents including cisplatin, gemcitabine, and pemetrexed, significantly enhance the efficacy of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) by increasing PD-L1 expression and potentiating T cell cytotoxicity. However, the low response rate and adverse effects limit the application of chemotherapy/ICI combinations in patients.

METHODS

We screened for medicinal herbs that could perturb PD-L1 expression and enhance T cell cytotoxicity in the presence of anti-PD-L1 antibody, and investigated the underlying mechanisms.

RESULTS

We found that the aqueous extracts of Centipeda minima (CM) significantly enhanced the cancer cell-killing activity and granzyme B expression level of CD8+ T cells, in the presence of anti-PD-L1 antibody. Both CM and its active component 6-O-angeloylplenolin (6-OAP) upregulated PD-L1 expression by suppressing GSK-3β-β-TRCP-mediated ubiquitination and degradation. CM and 6-OAP significantly enhanced ICI-induced reduction of tumor burden and prolongation of overall survival of mice bearing NSCLC cells, accompanied by upregulation of PD-L1 and increase of CD8+ T cell infiltration. CM also exhibited anti-NSCLC activity in cells and in a patient-derived xenograft mouse model.

CONCLUSIONS

These data demonstrated that the induced expression of PD-L1 and enhancement of CD8+ T cell cytotoxicity underlay the beneficial effects of 6-OAP-rich CM in NSCLCs, providing a clinically available and safe medicinal herb for combined use with ICIs to treat this deadly disease.

Cisplatin in the era of PARP inhibitors and immunotherapy

Platinum compounds such as cisplatin, carboplatin and oxaliplatin are widely used in chemotherapy. Cisplatin induces cytotoxic DNA damage that blocks DNA replication and gene transcription, leading to arrest of cell proliferation. Although platinum therapy alone is effective against many tumors, cancer cells can adapt to the treatment and gain resistance. The mechanisms for cisplatin resistance are complex, including low DNA damage formation, high DNA repair capacity, changes in apoptosis signaling pathways, rewired cell metabolisms, and others. Drug resistance compromises the clinical efficacy and calls for new strategies by combining cisplatin with other therapies. Exciting progress in cancer treatment, particularly development of poly (ADP-ribose) polymerase (PARP) inhibitors and immune checkpoint inhibitors, opened a new chapter to combine cisplatin with these new cancer therapies. In this Review, we discuss how platinum synergizes with PARP inhibitors and immunotherapy to bring new hope to cancer patients.

The significance of inflammatory markers in prognosticating the effectiveness and safety of immunotherapy in conjunction with chemotherapy during the primary intervention of advanced non-small cell lung carcinoma

OBJECTIVE

The aim of this study is to scrutinize the prognostic significance of inflammatory biomarkers concerning the effectiveness and safety of combining PD-1 inhibition with chemotherapy in the management of advanced NSCLC.

METHODS

We conducted a retrospective analysis involving 206 NSCLC patients who received treatment at Qingdao Municipal Hospital. The study encompassed the acquisition of baseline clinical attributes and hematological parameters of these patients. The optimal threshold values for PLT and NLR were ascertained based on pre-treatment evaluations, with a particular focus on their association with PFS. Variables linked to PFS were subject to scrutiny through Kaplan-Meier analysis and logistic regression. The Receiver Operating Characteristic (ROC) curve served as the means to determine the ideal cut-off values for categorizing levels of inflammatory markers into high and low classifications. We employed Chi-square tests to evaluate the relationship between elevated and reduced baseline levels of inflammatory markers and irAE.

RESULTS

Kaplan-Meier analysis disclosed that patients in the low baseline PLT group and the low NLR group exhibited a substantially more favorable prognosis in contrast to their counterparts in the high baseline PLT and high NLR groups. Multivariate analysis indicated that diminished baseline PLT and NLR levels before treatment independently foretell extended PFS. Chi-square analysis underscored a substantial correlation between baseline WBC, NEUT, LYMPH, MONO, and NLR levels and irAE.

CONCLUSION

Subdued baseline PLT and NLR levels may serve as indicators of a more auspicious prognosis in patients contending with advanced NSCLC undergoing the combination of PD-1 inhibition and chemotherapy. Elevated baseline levels of inflammatory markers antedating PD-1 therapy in advanced NSCLC may be intimately interrelated with the occurrence of irAE.

Identification of a cisplatin resistant-based prognostic immune related gene signature in MIBC

Cisplatin resistance plays a significant role in the dismal prognosis and progression of muscle-invasive bladder cancer (MIBC). However, the strategies to predict prognosis and cisplatin resistance are inefficient, and it remains unclear whether cisplatin resistance is associated with tumor immunity. In this study, we integrated the transcriptional data from cisplatin-resistant cell lines and a TCGA-MIBC cohort to establish cisplatin-resistance-related cluster classification and a cisplatin-resistance-related gene risk score (CRRGRS). Kaplan-Meier survival curves showed that compared with those in low CRRGRS group, MIBC patients belonging to high CRRGRS group had worse prognosis in TCGA-MIBC cohort and external GEO cohorts. Meanwhile, CRRGRS was able to help forecast chemotherapy and immunotherapy response of MIBC patients in the TGCA cohort and IMvigor210 cohort. Moreover, compared with the low CRRGRS group, the high CRRGS group possessed a relatively immunosuppressive "cold tumor" phenotype with a higher tumor immune dysfunction and exclusion (TIDE) score, ESTIMATE score, stromal score and immune score and a lower immunophenoscore (IPS) score. The upregulated expression levels of immune checkpoint genes, including PD-1, PD-L1 and CTLA4, in the high CRRGRS group also further indicated that a relative immunosuppressive tumor microenvironment may exist in MIBC patients belonging to high CRRGRS group. In addition, we integrated CRRGRS and clinical characteristics with prognostic value to develop a nomogram, which could help forecast overall survival of MIBC patients. Furthermore, DIAPH3 was identified as a regulator of proliferation and cisplatin resistance in MIBC. The expression of DIAPH3 was increased in cisplatin-resistant cell lines and chemotherapy-unsensitive people. Further mechanism exploration revealed that DIAPH3 facilitated tumor proliferation and cisplatin resistance by regulating the NF-kB and epithelial-mesenchymal transition (EMT) pathways. In conclusion, the comprehensive investigations of CRRGRS increased the understanding of cisplatin resistance and provided promising insights to restrain tumor growth and overcome chemoresistance by targeting DIAPH3.

Doxorubicin induces deglycosylation of cancer cell-intrinsic PD-1 by NGLY1

Tumor cells can express the immune checkpoint protein programmed death-1 (PD-1), but how cancer cell-intrinsic PD-1 is regulated in response to cellular stresses remains largely unknown. Here, we uncover a unique mechanism by which the chemotherapy drug doxorubicin (Dox) regulates cancer cell-intrinsic PD-1. Dox upregulates PD-1 mRNA while reducing PD-1 protein levels in tumor cells. Although Dox shortens the PD-1 half-life, it fails to directly induce PD-1 degradation. Instead, we observe that Dox promotes the interaction between peptide-N(4)-(N-acetyl-beta-glucosaminyl)asparagine amidase (NGLY1) and PD-1, facilitating NGLY1-mediated PD-1 deglycosylation and destabilization. The maintenance of PD-1 sensitizes tumor cells to Dox-mediated antiproliferative effects. Our study unveils a regulatory mechanism of PD-1 in response to Dox and highlights a potential role of cancer cell-intrinsic PD-1 in Dox-mediated antitumor effects.

Mitotic MTH1 inhibitor TH1579 induces PD-L1 expression and inflammatory response through the cGAS-STING pathway

The mitotic MTH1 inhibitor TH1579 is a dual inhibitor that inhibits mitosis and incorporation of oxidative DNA damage and leads to cancer-specific cell death. The response to immune checkpoint inhibitor (ICI) treatment is often augmented by DNA damaging agents through the cGAS-STING pathway. This study investigates whether TH1579 can improve the efficacy of immune checkpoint blockades through its immunomodulatory properties. Various human and murine cancer cell lines were treated with mitotic MTH1i TH1579, and the expression of PD-L1 and T-cell infiltration-related chemokines was analysed by flow cytometry and real-time qPCR. Syngeneic mouse models were established to examine the combined effect of TH1579 and PD-L1 blockade. In our investigation, we found that TH1579 upregulates PD-L1 expression at both the protein and mRNA levels in human cancer cell lines. However, in murine cell lines, the increase was less pronounced. An in vivo experiment in a syngeneic mouse melanoma model showed that TH1579 treatment significantly increased the efficacy of atezolizumab, an anti-PD-L1 antibody, compared to vehicle or atezolizumab monotherapy. Furthermore, TH1579 exhibited immune-modulatory properties, elevating cytokines such as IFN-β and chemokines including CCL5 and CXCL10, in a cGAS-STING pathway-dependent manner. In conclusion, TH1579 has the potential to improve ICI treatment by modulating immune checkpoint-related proteins and pathways.

The efficacy and safety of neoadjuvant chemoradiotherapy combined with immunotherapy for locally advanced rectal cancer patients: a systematic review

Background

Several studies have explored the effectiveness of PD-1/PD-L1 inhibitors combined with neoadjuvant chemoradiotherapy (nCRT) in the treatment of locally advanced rectal cancer(LARC), particularly in microsatellite stable(MSS) or mismatch repair proficient(pMMR) LARC patients. We undertook a single-arm systematic review to comprehensively evaluate the advantages and potential risks associated with the use of PD-1/PD-L1 inhibitors in conjunction with nCRT for patients diagnosed with locally advanced rectal cancer.

Methods

The PubMed, Embase, Cochrane Library, ClinicalTrials.gov, ASCO and ESMO were searched for related studies. The main outcomes were pathologic complete response (pCR), major pathological response (MPR), anal preservation, and adverse effects (AEs).

Results

Fourteen articles including 533 locally advanced rectal cancer (LARC) patients were analyzed. The pooled pCR, MPR, and anal preservation rates were 36%, 66% and 86%. Grade ≥3 adverse events occurred in 20%. Subgroup analysis showed that; dMMR/MSI-H had a pooled pCR (100%) and MPR (100%), pMMR/MSS had a pooled pCR (38%) and MPR (60%); the short-course radiotherapy and long-course radiotherapy had pooled pCR rates of 51% and 30%, respectively. The rates of pCR for the concurrent and sequential immuno-chemoradiotherapy subgroups at 30% and 40%, mirroring pCR rates for the PD-L1 and PD-1 inhibitor subgroups were 32% and 40%, respectively.

Conclusion

In cases of locally advanced rectal cancer, PD-1/PD-L1 inhibitors combined with neoadjuvant chemoradiotherapy have shown promising response rates and acceptable toxicity profiles. PD-1/PD-L1 inhibitors combined with neoadjuvant chemoradiotherapy hence has a positive outcome even in MSS LARC patients.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/#myprospero, identifier CRD42023465380.

Dihydroartemisinin, a potential PTGS1 inhibitor, potentiated cisplatin-induced cell death in non-small cell lung cancer through activating ROS-mediated multiple signaling pathways

Dihydroartemisinin (DHA) exerts an anti-tumor effect in multiple cancers, however, the molecular mechanism of DHA and whether DHA facilitates the anti-tumor efficacy of cisplatin in non-small cell lung cancer (NSCLC) are unclear. Here, we found that DHA potentiated the anti-tumor effects of cisplatin in NSCLC cells by stimulating reactive oxygen species (ROS)-mediated endoplasmic reticulum (ER) stress, C-Jun-amino-terminal kinase (JNK) and p38 MAPK signaling pathways both in vitro and in vivo. Of note, we demonstrated for the first time that DHA inhibits prostaglandin G/H synthase 1 (PTGS1) expression, resulting in enhanced ROS production. Importantly, silencing PTGS1 sensitized DHA-induced cell death by increasing ROS production and activating ER-stress, JNK and p38 MAPK signaling pathways. In summary, our findings provided new experimental basis and therapeutic prospect for the combined therapy with DHA and cisplatin in some NSCLC patients.

Immune checkpoint inhibitor for different age patients with NSCLC in efficacy: A systematic review and meta-analysis

OBJECTIVE

This article is a Meta-analysis aiming to systematically evaluate the difference in efficacy of immune checkpoint inhibitor in patients with non-small cell lung cancer (NSCLC) by age.

METHODS

We performed a Meta-analysis of published randomized controlled trials concerning for patients with NSCLC by age. We compared overall survival among three groups (age <65 years, age 65-75 years, age ≥75 years). Hazard ratios (HRs) and 95% confidence intervals (CIs) were collected and pooled.

RESULTS

A total of 10,291 patients from 17 RCTs were included. In the group under age 65 years, immune checkpoint inhibitor can significantly prolong the overall survival of patients with NSCLC (HR = 0.73, 95% CI: 0.66∼0.81, P < 0.00001). In the age 65-75 years group, immune checkpoint inhibitors prolonged overall survival in patients with NSCLC (HR = 0.78, 95% CI:0.71∼0.84, P < 0.00001). However, it has no significant effect on the overall survival of NSCLC patients (HR = 0.88, 95% CI:0.72∼1.08, P > 0.05) in the group older than 75 years.

CONCLUSIONS

Immune checkpoint inhibitors prolonged the overall survival of NSCLC patients in the age <65 years group and the age 65-75 years group, but in the age ≥75 years group, there was no significant effect on overall survival. This may be related to innate immune and adaptive immune dysregulation due to "immunosenescence" in older patients.

Use of non-small cell lung cancer multicellular tumor spheroids to study the impact of chemotherapy

BACKGROUND

Lung cancers represent the main cause of cancer related-death worldwide. Recently, immunotherapy alone or in combination with chemotherapy has deeply impacted the therapeutic care leading to an improved overall survival. However, relapse will finally occur, with no efficient second line treatment so far. New therapies development based on the comprehension of resistance mechanisms is necessary. However, the difficulties to obtain tumor samples before and after first line treatment hamper to clearly understand the consequence of these molecules on tumor cells and also to identify adapted second line therapies.

METHODS

To overcome this difficulty, we developed multicellular tumor spheroids (MCTS) using characterized Non-Small Cell Lung Cancer (NSCLC) cell lines, monocytes from healthy donors and fibroblasts. MCTS were treated with carboplatin-paclitaxel or -gemcitabine combinations according to clinical administration schedules. The treatments impact was studied using cell viability assay, histological analyses, 3'RNA sequencing, real-time PCR, flow cytometry and confocal microscopy.

RESULTS

We showed that treatments induced a decrease in cell viability and strong modifications in the transcriptomic profile notably at the level of pathways involved in DNA damage repair and cell cycle. Interestingly, we also observed a modification of genes expression considered as hallmarks of response to immune check point inhibitors and immunogenicity, particularly an increase in CD274 gene expression, coding for PD-L1. This result was validated at the protein level and shown to be restricted to tumor cells on MCTS containing fibroblasts and macrophages. This increase was also observed in an additional cell line, expressing low basal CD274 level.

CONCLUSIONS

This study shows that MCTS are interesting models to study the impact of first line therapies using conditions close to clinical practice and also to identify more adapted second line or concomitant therapies for lung cancer treatment.

Boosting immune responses in lung tumor immune microenvironment: A comprehensive review of strategies and adjuvants

The immune system has a substantial impact on the growth and expansion of lung malignancies. Immune cells are encompassed by a stroma comprising an extracellular matrix (ECM) and different cells like stromal cells, which are known as the tumor immune microenvironment (TIME). TME is marked by the presence of immunosuppressive factors, which inhibit the function of immune cells and expand tumor growth. In recent years, numerous strategies and adjuvants have been developed to extend immune responses in the TIME, to improve the efficacy of immunotherapy. In this comprehensive review, we outline the present knowledge of immune evasion mechanisms in lung TIME, explain the biology of immune cells and diverse effectors on these components, and discuss various approaches for overcoming suppressive barriers. We highlight the potential of novel adjuvants, including toll-like receptor (TLR) agonists, cytokines, phytochemicals, nanocarriers, and oncolytic viruses, for enhancing immune responses in the TME. Ultimately, we provide a summary of ongoing clinical trials investigating these strategies and adjuvants in lung cancer patients. This review also provides a broad overview of the current state-of-the-art in boosting immune responses in the TIME and highlights the potential of these approaches for improving outcomes in lung cancer patients.

Transforming the landscape of colorectal cancer treatment with immunotherapy: Evolution and future horizons

Colorectal cancer (CRC) continues to be one of the most prevalent and lethal cancers worldwide. Over the past decades, immune checkpoint inhibitors (ICIs) have shown to significantly improve patient outcomes in mismatch repair-deficient metastasized CRC. However, widening the scope of this novel treatment modality has been the object of growing interest. This article will review several landmark trials, while exploring various aspects of this rapidly evolving field, including potential neoadjuvant (or even entirely nonsurgical) and adjuvant indications in localized disease. We will also discuss differences between management of rectal and colon cancer, current and expected challenges (eg. resistance, toxicities, pseudoprogression, biomarkers) and other future opportunities including combinations with other therapeutic agents and the role of ICIs in the treatment of both deficient as well as proficient mismatch repair (dMMR and pMMR respectively) CRC.

Immunotherapy for the treatment of biliary tract cancer: an evolving landscape

Biliary tract cancers (BTCs), consisting of intrahepatic and extrahepatic cholangiocarcinoma and gallbladder cancer, are an aggressive, heterogeneous malignancy. They are most often diagnosed in the locally advanced or metastatic setting, at which point treatment consists of systemic therapy or best supportive care. Our understanding of the tumor microenvironment and the molecular classification has led to the identification of targetable mutations, such as isocitrate dehydrogenase 1 and fibroblast growth factor receptor 2. Despite the identification of these genomic alterations, until recently, little advancement had been made in the first-line setting for advanced BTC. While immunotherapy (IO) has revolutionized the treatment of many malignancies, the use of IO in BTC had yielded limited results prior to TOPAZ-1. In this review, we discuss the systemic therapeutic advances for BTC over the past decade, the rationale for immunotherapy in BTC, prior trials utilizing IO in BTC, and current and emerging immune-based therapeutic options. We further analyze the culmination of these advances, which resulted in the approval of durvalumab with gemcitabine and cisplatin for the first-line treatment of BTC per TOPAZ-1. We also discuss the results of KEYNOTE-966, which similarly reported improved clinical outcomes with the use of pembrolizumab in combination with gemcitabine and cisplatin.

Immunomodulatory effects and improved outcomes with cisplatin- versus carboplatin-based chemotherapy plus atezolizumab in urothelial cancer

In metastatic urothelial cancer (mUC), cisplatin versus carboplatin leads to durable disease control in a subset of patients. The IMvigor130 trial reveals more favorable effects with atezolizumab combined with gemcitabine and cisplatin (GemCis) versus gemcitabine and carboplatin (GemCarbo). This study investigates the immunomodulatory effects of cisplatin as a potential explanation for these observations. Our findings indicate that improved outcomes with GemCis versus GemCarbo are primarily observed in patients with pretreatment tumors exhibiting features of restrained adaptive immunity. In addition, GemCis versus GemCarbo ± atezolizumab induces transcriptional changes in circulating immune cells, including upregulation of antigen presentation and T cell activation programs. In vitro experiments demonstrate that cisplatin, compared with carboplatin, exerts direct immunomodulatory effects on cancer cells, promoting dendritic cell activation and antigen-specific T cell killing. These results underscore the key role of immune modulation in cisplatin's efficacy in mUC and highlight the importance of specific chemotherapy backbones in immunotherapy combination regimens.

Atractylenolide II ameliorates myocardial fibrosis and oxidative stress in spontaneous hypertension rats

BACKGROUND

Hypertension is a well-recognized risk factor for cardiovascular, which is also a critical factor in causing myocardial fibrosis (MF).

OBJECTIVE

The study aimed to explore the effect of Atractylenolide II (ATL-II) on MF and oxidative stress in spontaneous hypertension rats (SHR).

METHODS

The body weight of rats after injection of ATL-II was quantitatively analyzed. The left ventricular function of SHR was evaluated by Echocardiographic. HE staining, Masson trichrome staining, left ventricular mass index (LVMI) and immunofluorescence was applied to investigate the effects of ATL-II on MF. RT qPCR was used to detect the Collagen I, α-SMA, Fibronectin, and Vimentin mRNA expression levels in myocardial slices. The effect ATL-II on cardiomyocyte apoptosis was detected by TUNEL staining and western blot. An immunohistochemistry assay was conducted to detect α-SMA protein and TGF-β1 protein. The contents of H2O2, GSH-PX, SOD, and MDA were measured by colorimetry.

RESULTS

ATL-II could dose-dependently improve the BW of SHRs (P< 0.05) and enhance myocardial function. Moreover, ATL-II effectively reduced cardiomyocyte apoptosis in SHRs. Alternatively, ATL-II could inhibit the Collagen I, α-SMA, Fibronectin, and Vimentin mRNA and protein expression levels in SHRs. ATL-II could ameliorate oxidative stress by improving the activities of SOD and GSH-PX and lowering the contents of H2O2 and MDA in ATL-II-treated SHRs, which reach about 80%.

CONCLUSION

ATL-II could exert an inhibiting effect on MF and oxidative stress in SHRs. Hence, ATL-II may hold promise for the treatment of MF and oxidative stress in Spontaneous Hypertension.

Immune Checkpoint Inhibitor Plus Chemotherapy as First-Line Treatment for Advanced Gastric or Gastroesophageal Junction Cancer: A Systematic Review and Meta-Analysis

Background: Immune checkpoint inhibitor (ICI) plus chemotherapy is effective in advanced gastric or gastroesophageal junction (G/GEJ) cancer. This study aims to evaluate the clinical effect of first-line immunotherapy in combination with chemotherapy for advanced G/GEJ cancer. Methods: PubMed, Web of Science, Embase and Cochrane databases were systematically searched from the inception of the databases to December 2021. Randomized trials comparing ICI plus chemotherapy with chemotherapy in first-line treatment for advanced G/GEJ cancer were included. The outcomes were overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs). Analyses were performed in Stata 14.0 software. The study protocol was registered with PROSPERO, number CRD42022300907. Results: Five trials were included for analysis, involving 2, 814 patients. ICI plus chemotherapy can significantly improve OS (hazards ratio [HR], 0.86; 95% CI 0.78-0.94; P = .002), PFS (HR, 0.79; 95% CI 0.63-0.99; P ＜ .001) and ORR (relative ratio [RR], 1.20; 95% CI 1.11-1.30; P < .001). In safety analyses, there were no significant differences in incidence of all AEs, treatment-related adverse event (TRAE), TRAE of grade 3 or higher, serious TRAE and TRAE leading to death between two arms (P > .05). Conclusions: ICI plus chemotherapy is more effective first-line treatment for advanced G/GEJ cancer in contrast to chemotherapy regrading to improving OS, PFS and ORR, without increasing TRAE risk. This study will redefine the role of ICI in combination with chemotherapy in the first-line setting for G/GEJ cancer, and provide reference for clinical treatment.

Stromal and tumor immune microenvironment reprogramming through multifunctional cisplatin-based liposomes boosts the efficacy of anti-PD-1 immunotherapy in pancreatic cancer

The dense stromal barrier in pancreatic cancer tissues blocks intratumoral delivery and distribution of chemotherapeutics and therapeutic antibodies, causing poor chemoimmunotherapy responses. We designed a multi-targeted pH-sensitive liposome which encapsulates cisplatin (Pt) in its water core (denoted as ATF@Pt Lps) and shows high affinity for uPAR receptors in pancreatic cancer cells, tumor-associated macrophages, and cancer-associated fibroblasts. Systemic administration of ATF@Pt Lps enabled overcoming the central stromal cellular barrier and effective drug delivery into tumor cells, resulting in a strong therapeutic response in a Panc02 cell derived transplanted tumor mouse model. More importantly, ATF@Pt Lps degradation of collagen contributes to the infiltration of CD8+ T cells into tumors as well as an enhanced accumulation of anti PD-1 monoclonal antibodies. Furthermore, the killing of tumor cells by Pt also leads to the release of tumor antigens, which promote the proliferation of immune cells, especially CD83+ cells, Th1 CD4+ cells, and CD8+ cytotoxic T cells, that converted an immunoscore "cold" pancreatic cancer into a pro-immune "hot" tumor. A further combination with an immune checkpoint agent, anti PD-1 antibodies that inhibit PD-1, can enhance tumor specific cytotoxic T cell response. Accordingly, ATF@Pt Lps displays multi-targeting, controlled drug release, stromal disruption, enhanced penetration, killing of cancer cells, modification of the immunosuppressive microenvironment, and enhancement of immunity. This study provides important mechanistic information for the further development of a combination of ATF@Pt Lps and anti PD-1 antibodies for the effective treatment of pancreatic cancer.

CD200/CD200R: Bidirectional Role in Cancer Progression and Immunotherapy

As an immune checkpoint molecule, CD200 serves a foundational role in regulating immune homeostasis and promoting self-tolerance. While CD200 expression occurs in various immune cell subsets and normal tissues, its aberrant expression patterns in hematologic malignancies and solid tumors have been linked to immune evasion and cancer progression under pathological conditions, particularly through interactions with its cognate receptor, CD200R. Through this CD200/CD200R signaling pathway, CD200 exerts its immunosuppressive effects by inhibiting natural killer (NK) cell activation, cytotoxic T cell functions, and M1-polarized macrophage activity, while also facilitating expansion of myeloid-derived suppressor cells (MDSCs) and Tregs. Moreover, CD200/CD200R expression has been linked to epithelial-to-mesenchymal transition and distant metastasis, further illustrating its role in cancer progression. Conversely, CD200 has also been shown to exert anti-tumor effects in certain cancer types, such as breast carcinoma and melanoma, indicating that CD200 may exert bidirectional effects on cancer progression depending on the specific tumor microenvironment (TME). Regardless, modulating the CD200/CD200R axis has garnered clinical interest as a potential immunotherapeutic strategy for cancer therapy, as demonstrated by early-phase clinical trials. However, further research is necessary to fully understand the complex interactions of CD200 in the tumor microenvironment and to optimize its therapeutic potential in cancer immunotherapy.

Immune Checkpoint Inhibitors in pMMR/MSS Colorectal Cancer

BACKGROUND

Immune checkpoint inhibitors have recently replaced over chemotherapy as the first-line treatment for microsatellite instability-high or mismatch repair deficient (dMMR/MSI-H) stage 4 colorectal cancers. Considering this success, many studies have tried to replicate the use of immune checkpoint inhibitors, either as a single agent or in combination with other therapeutic agents, in the treatment of proficient mismatch repair (pMMR/MSS) stage 4 colorectal cancers. This review summarizes the seminal clinical data about the immune checkpoint inhibitors used in pMMR/MSS colorectal cancers and some future directions.

RESULTS

Studies concerning the use of immune checkpoint inhibitors as a single agent or in combination with other immune checkpoint inhibitors, targeted therapy, chemotherapy, or radiotherapy have proven inefficient in the treatment of pMMR/MSS colorectal cancer. However, a small subset of patients with pMMR/MSS colorectal cancer who has a mutation in POLE and POLD1 enzymes may respond to immunotherapy. Moreover, patients without liver metastasis appear to have a better chance of response. New immune checkpoint targets are being identified, such as VISTA, TIGIT, LAG3, STING signal pathway, and BTLA, and studies are ongoing to determine their efficiency in this disease type.

CONCLUSION

Immune checkpoint inhibitor-based regimens have not yet shown any meaningful positive outcomes for most pMMR/MSS colorectal cancers. A beneficial effect among a minority of these patients has been observed, but concrete biomarkers of response are lacking. Understanding the underlying mechanisms of immune resistance should guide further research for overcoming these obstacles.

Eicosapentaenoic acid enhances the sensitivity of osteosarcoma to cisplatin by inducing ferroptosis through the DNA-PKcs/AKT/NRF2 pathway and reducing PD-L1 expression to attenuate immune evasion

Acquired drug resistance poses a significant challenge in osteosarcoma therapy. Therefore, it is necessary for us to discover and develop an alternative anti-cancer strategy. Previous studies have shown that eicosapentaenoic acid (EPA) significantly increases chemosensitivity in cancer cells. In this study, we discovered that EPA enhances the sensitivity of osteosarcoma to cisplatin (DDP). Interestingly, in addition to inhibiting growth and inducing apoptosis, EPA also enhances DDP-induced ferroptosis. Western blot analysis confirmed that EPA treatment significantly decreases the expression of DNA-dependent protein kinase catalytic subunit (DNA-PKcs), p-AKT, nuclear factor erythroid 2-related factor 2 (NRF2), and glutathione peroxidase 4 (GPX4) in cells. Knockdown of DNA-PKcs by siRNA further enhances the level of ferroptosis induced by EPA. Importantly, EPA can reverse the high expression level of programmed death ligand 1 (PD-L1) induced by DDP. ELISA and western blotting analysis revealed that EPA treatment decreases the levels of IL-6 and p-STAT3, which are increased by DDP treatment. Furthermore, a co-immunoprecipitation (co-IP) assay confirmed the interaction between DNA-PKcs and PD-L1, and knockdown of DNA-PKcs further reduces the expression of PD-L1. This data provides the first evidence that EPA suppresses the DNA-PKcs/AKT/NRF2/GPX4 pathway to enhance ferroptosis, and inhibits IL-6/STAT3 and DNA-PKcs to decrease PD-L1 expression, thereby sensitizing osteosarcoma to DDP. The combination of EPA and DDP presents an encouraging and promising anti-tumor strategy.

Dynamic Up-Regulation of PD-L1 in the Progression of Oral Squamous Cell Carcinoma

The introduction of immune checkpoint inhibition for recurrent and metastatic head and neck cancer has brought a new treatment option for patients suffering from advanced oral cancers without a chance for curation using surgery or radiotherapy. The application of immune checkpoint inhibitors in most cases is based on the expression levels of PD-L1 in the tumor tissue. To date, there is a lack of data on the dynamic regulation of PD-L1 during disease progression. Therefore, this study aimed to evaluate the expression levels of PD-L1 in a large cohort of patients (n = 222) with oral squamous cell carcinoma including primary and recurrent tumors. Semiautomatic digital pathology scoring was used for the assessment of PD-L1 expression levels in primary and recurrent oral squamous cell carcinoma. Survival analysis was performed to evaluate the prognostic significance of the protein expression at different stages of the disease. We found a significant up-regulation of PD-L1 expression from primary disease to recurrent tumors (mean PD-L1 H-scores: primary tumors: 47.1 ± 31.4; recurrent tumors: 103.5 ± 62.8, p < 0.001). In several cases, a shift from low PD-L1 expression in primary tumors to high PD-L1 expression in recurrent tumors was identified. Multivariate Cox regression analysis did not reveal a significantly higher risk of death (p = 0.078) or recurrence (p = 0.926) in patients with higher PD-L1 expression. Our findings indicate that the exclusive analysis of primary tumor tissue prior to the application of checkpoint blockade may lead to the misjudgment of PD-L1 expression in recurrent tumors.

PD-L1 expression in recurrent or metastatic head and neck squamous cell carcinoma in China (EXCEED study): a multicentre retrospective study

AIMS

Programmed death-ligand 1 (PD-L1) is known to be highly expressed in various malignancies, including head and neck squamous cell carcinoma (HNSCC). We aimed to determine the prevalence of PD-L1 expression in recurrent or metastatic HNSCC (R/M HNSCC) among Chinese patients.

METHODS

This multicentre, retrospective analysis of data from six centres in China included patients with R/M HNSCC treated from 9 August 2021 to 28 February 2022. PD-L1 expression in tumour tissue was assessed and represented using a combined positive score (CPS). The χ2 and Cochran-Mantel-Haenszel χ2 tests were used to compare the prevalence of different PD-L1 expression statuses according to related co-variables.

RESULTS

For all 402 examined patients with R/M HNSCC, 168 cases (41.8%) had PD-L1 expression with a CPS ≥20, and 337 cases (83.8%) had PD-L1 expression with a CPS ≥1. Between the PD-L1 CPS ≥20 group and PD-L1 CPS <20 group, statistically significant differences were observed for variables of sex (p<0.001), smoking habit (p=0.0138 for non-smokers vs current smokers) and primary tumour site (p<0.001 for hypopharynx vs oral cavity and p=0.0304 for larynx vs oral cavity, respectively).

CONCLUSION

PD-L1 with CPS ≥20 was expressed in about 41.8% of cases with R/M HNSCC among Chinese patients, and PD-L1 expression was significantly associated with sex, smoking history and primary tumour site. Our findings regarding the variables related to PD-L1 expression level provide insight for clinical practice and a solid basis for future research on immunotherapy in HNSCC.

TRIAL REGISTRATION NUMBER

ISRCTN10570964.

Crosstalk between PD-L1 and Jak2-Stat3/ MAPK-AP1 signaling promotes oral cancer progression, invasion and therapy resistance

BACKGROUND

Programmed cell death ligand-1 (PD-L1)is an antitumor immunity molecule and a great target to cure oral cancer; nonetheless, the limited success can be attributed to many complex pathways and tumor-related interferences.

METHODS

In the present study, 150 human oral squamous cell carcinoma (OSCC) tissue samples, including 17 adjacent normals, 56 primary tumors, 47 invasive tumors, and 30 therapy-resistant (RT) samples, were included. The parental/cisplatin-resistant (CisR-SCC4/9) cells were utilized for overexpression (Jak1-3 wild type and catalytically inactive), knockdown (PD-L1 siRNA), targeting MAPK/PI3K/Jak-Stat pathways (SMIs) and checking microsomes. The expression of PD-L1, transcription factors (TFs), signaling pathways, survival/apoptosis, therapy resistance, and invasiveness-related molecules/their activity were determined by RT-PCR, Immunohistochemistry, Western blot, Gelatin Zymography, and MTT assay.

RESULTS

Advanced OSCC tumors (invasive and drug-resistance), CisR-SCC4/9 cells, and secretory exosomes (CisR-SCC4/9) were found with increased PD-L1 expression. PD-L1 mRNA/protein showed a positive correlation with different TFs (AP1 > Stat3 > c-myc > NFκB) in tumor samples. The PD-L1 expression was more influenced by Jak-Stat/ MAPK-AP1 pathways over PI3K. The ectopic expression of Jak1-3 suggests Jak2 inducted PD-L1 level over Jak1/Jak3. Finally, PD-L1 directly supports survival (Bcl-xL, Bax, cleaved caspase-3), invasion (MMP2/9), and drug-resistance (ALDH-1A1/-3A1) program in OSCC through its link with several molecules.

CONCLUSIONS

PD-L1 was regulated mainly by the Jak2-Stat3/ MAPK-AP1 pathway, and besides the routine immunological functions, it supports OSCC survival, invasion, and therapy resistance. PD-L1 can be used as an indicator of severity and can be targeted along with Jak2-Stat3/ MAPK-AP1 for a better outcome OSCC.

Do patients receive any benefit from the addition of perioperative immunotherapy-chemotherapy for solid tumors?

BACKGROUND

Progress in the use of neoadjuvant immunotherapy combined with chemotherapy has become a highlight of cancer research. Our meta-analysis aimed to better elucidate the activity, efficacy and safety of this combination using data obtained from randomized controlled trials (RCTs).

METHODS

A systematic search of PubMed, Embase, Web of Science, the Cochrane Library and conference proceedings up to January 31, 2023 was carried out to identify RCTs investigating neoadjuvant immunotherapy combined with chemotherapy for the treatment of solid tumors. Using fixed- and random-effects models, pooled odds ratios (ORs) and hazard ratios with 95% confidence intervals (CIs) were calculated for pathological complete response (pCR, defined as ypT0/is pN0) and immunotherapy treatment-related adverse events.

RESULTS

A total of 1876 studies were identified, and 6 RCTs (N = 2558 patients) were included. The pCR was significantly higher with neoadjuvant immunotherapy combined with chemotherapy than with neoadjuvant chemotherapy alone (OR = 2.30, 95% CI: 1.43-3.71, P < .001). The pCR was confirmed to be statistically significant in the PD-L1-positive subgroup (OR = 2.01; 95% CI: 1.55-2.59, P = .012). The pCR was confirmed to be statistically significant in the PD-1 inhibitor subgroup (OR = 4.17; 95% CI: 1.47-11.87, P = .000), while no statistically significant was observed in the PD-L1 inhibitor subgroup (OR = 1.52; 95% CI: 1.12-2.07, P = .308). The pooled ORs of any grade treatment-related or immunotherapy-related adverse events were significant, but the grade 3-4 immunotherapy-related adverse events were not.

CONCLUSION

Our study provides comprehensive data that the addition of PD1 blockade to neoadjuvant chemotherapy resulted in better treatment efficacy than neoadjuvant chemotherapy alone in patients with solid tumors and had a similar safety profile.

In vitro vascularized immunocompetent patient-derived model to test cancer therapies

This work describes a patient-derived tumoroid model (PDTs) to support precision medicine in lung oncology. The use of human adipose tissue-derived microvasculature and patient-derived peripheral blood mononuclear cells (PBMCs) permits to achieve a physiologically relevant tumor microenvironment. This study involved ten patients at various stages of tumor progression. The vascularized, immune-infiltrated PDT model could be obtained within two weeks, matching the requirements of the therapeutic decision. Histological and transcriptomic analyses confirmed that the main features from the original tumor were reproduced. The 3D tumor model could be used to determine the dynamics of response to antiangiogenic therapy and platinum-based chemotherapy. Antiangiogenic therapy showed a significant decrease in vascular endothelial growth factor (VEGF)-A expression, reflecting its therapeutic effect in the model. In an immune-infiltrated PDT model, chemotherapy showed the ability to decrease the levels of lymphocyte activation gene-3 protein (LAG-3), B and T lymphocyte attenuator (BTLA), and inhibitory receptors of T cells functions.

The nexus of dynamic T cell states and immune checkpoint blockade therapy in the periphery and tumor microenvironment

Immune checkpoint blockade (ICB) therapies, that is, using monoclonal antibodies to reinvigorate tumor-reactive, antigen-specific T cells from the inhibitory effects of CTLA-4, PD-1 and PD-L1 immune checkpoints, have revolutionized the therapeutic landscape of modern oncology. However, only a subset of patients can benefit from the ICB therapy. Biomarkers associated with ICB response, resistance and prognosis have been subjected to intensive research in the past decade. Early studies focused on the analysis of tumor specimens and their residing microenvironment. However, biopsies can be challenging to obtain in clinical practice, and do not reflect the dynamic changes of immunological parameters during the ICB therapy. Recent studies have investigated profiles of antigen-specific T cells derived from the peripheral compartment using multi-omics approaches. By tracking the clonotype and diversity of tumor-reactive T cell receptor repertoire, these studies collectively establish that de novo priming of antigen-specific T cells in peripheral blood occurs throughout the course of ICB, whereas preexisting T cells prior to ICB are exhausted to various degrees. Here, we review what is known about ICB-induced T cell phenotypic and functional changes in cancer patients both within the tumor microenvironment and in the peripheral compartment. A better understanding of parameters influencing the response to ICBs will provide rationales for developing novel diagnostics and combinatorial therapeutic strategies to maximize the clinical efficacies of ICB therapies.

Poliovirus receptor (PVR) mediates carboplatin-induced PD-L1 expression in non-small-cell lung cancer cells

Programmed death-ligand-1 (PD-L1) is an immune suppressor that inhibits T cell based immunity. Anti-PD-L1/PD-1 immunotherapy benefits those patients receiving platinum-based combinational chemotherapy. However, the underlying mechanism is still largely unknown. In this study, we found that carboplatin could induce PD-L1 expression in NSCLC H292, A549 and H1299 cells in a dose-dependent manner. mRNA sequencing and the subsequent validation assays found that carboplatin significantly induced PVR expression, which is considered as an immuno-adhesion molecule. Mechanistically, PVR knockdown significantly abrogated carboplatin-induced PD-L1 expression. Functionally, knockdown of PVR significantly reversed the CD3+ T cells proliferation inhibition caused by carboplatin increased PD-L1. Moreover, the carboplatin-induced PVR and subsequent up-regulation of PD-L1 might be mediated via the EGFR, PI3K/AKT, and ERK signaling pathways. Immunohistochemical staining results showed that the PD-L1 expression was positively associated with PVR expression in clinical NSCLC samples. Our study reveals a novel regulatory mechanism of PD-L1 expression, provides evidence that carboplatin inhibits tumor immune response by up-regulating PD-L1 expression and explains the rationale for combining platinum-based chemotherapy with PD-L1/PD-1 inhibitors.

Modulation of PD‑L1 expression by standard therapy in head and neck cancer cell lines and exosomes

Although checkpoint inhibitors (CPI) have recently extended the treatment options and improved clinical response of advanced stage head and neck squamous cell carcinoma (HNSCC), treatment success remains unpredictable. Programmed cell death ligand‑1 (PD‑L1) is a key player in immunotherapy. Tumor cells, and exosomes derived therefrom, are carriers of PD‑L1 and efficiently suppress immune responses. The aim of the present study was to analyze the influence of established therapies on PD‑L1 expression of HNSCC cell lines and their exosomes. The HNSCC cell lines, UM‑SCC‑11B, UM‑SCC‑14C and UM‑SCC‑22C were treated with fractionated radiotherapy (RT; 5x2 Gy), cisplatin (CT) and cetuximab (Cetux) as monotherapy, or combined therapy, chemoradiotherapy (CRT; RT and CT) or radioimmunotherapy (RT and Cetux). The expression of PD‑L1 and phosphorylated (p)ERK1/2 as a mediator of radioresistance were assessed using western blotting, immunohistochemistry and an ex vivo vital tissue culture model. Additionally, exosomes were isolated from concentrated supernatants of the (un‑)treated HNSCC cell lines by size exclusion chromatography. Exosomal protein expression levels of PD‑L1 were detected using western blotting and semi‑quantitative levels were calculated. The functional impact of exosomes from the (un‑)treated HNSCC cell lines on the proliferation (MTS assay) and apoptosis (Caspase 3/7 assay) of the untreated HNSCC cell lines were measured and compared. The HNSCC cell lines UM‑SCC‑11B and UM‑SCC‑22B showed strong expression of pERK1/2 and PD‑L1, respectively. RT upregulated the PD‑L1 expression in UM‑SCC‑11B and UM‑SCC‑14C and in exosomes from all three cell lines. CT alone induced PD‑L1 expression in all cell lines. CRT induced the expression of PD‑L1 in all HNSCC cell lines and exosomes from UM‑SCC‑14C and UM‑SCC‑22B. The data indicated a potential co‑regulation of PD‑L1 and activated ERK1/2, most evident in UM‑SCC‑14C. Exosomes from irradiated UM‑SCC‑14C cells protected the unirradiated cells from apoptosis by Caspase 3/7 downregulation. The present study suggested a tumor cell‑mediated regulation of PD‑L1 upon platinum‑based CRT in HNSCC and in exosomes. A co‑regulation of PD‑L1 and MAPK signaling response was hypothesized.

Resistance to anti-PD-1/anti-PD-L1: galectin-3 inhibition with GB1211 reverses galectin-3-induced blockade of pembrolizumab and atezolizumab binding to PD-1/PD-L1

Background

Galectin-3 (Gal-3) is a β-galactoside-binding lectin that is highly expressed within the tumor microenvironment of aggressive cancers and has been suggested to predict a poor response to immune checkpoint therapy with the anti-PD-1 monoclonal antibody pembrolizumab. We aimed to assess if the effect of Gal-3 was a result of direct interaction with the immune checkpoint receptor.

Methods

The ability of Gal-3 to interact with the PD-1/PD-L1 complex in the absence and presence of blocking antibodies was assessed in in vitro biochemical and cellular assays as well as in an in vivo syngeneic mouse cancer model.

Results

Gal-3 reduced the binding of the checkpoint inhibitors pembrolizumab (anti-PD-1) and atezolizumab (anti-PD-L1), by potentiating the interaction between the PD-1/PD-L1 complex. In the presence of a highly selective Gal-3 small molecule inhibitor (GB1211) the binding of the anti-PD-1/anti-PD-L1 therapeutics was restored to control levels. This was observed in both a surface plasmon resonance assay measuring protein-protein interactions and via flow cytometry. Combination therapy with GB1211 and an anti-PD-L1 blocking antibody reduced tumor growth in an in vivo syngeneic model and increased the percentage of tumor infiltrating T lymphocytes.

Conclusion

Our study suggests that Gal-3 can potentiate the PD-1/PD-L1 immune axis and potentially contribute to the immunosuppressive signalling mechanisms within the tumor microenvironment. In addition, Gal-3 prevents atezolizumab and pembrolizumab target engagement with their respective immune checkpoint receptors. Reversal of this effect with the clinical candidate GB1211 offers a potential enhancing combination therapeutic with anti-PD-1 and -PD-L1 blocking antibodies.

Neoadjuvant anti-PD-1/PD-L1 therapy for colorectal cancer: Current status and future prospects

Immunotherapy, particularly programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) inhibitors, has made revolutionary progress in the treatment strategies for various types of cancer. Regarding colorectal cancer (CRC), the current clinical application of PD-1/PD-L1 inhibitors is primarily categorized based on mutation patterns, including deficient mismatch repair (dMMR)/high microsatellite instability (MSI-H) and proficient mismatch repair (pMMR) or non-high microsatellite instability (non-MSI-H). PD-1/PD-L1 inhibitors have demonstrated good efficacy against dMMR/MSI-H CRC by increasing T-cell infiltration into tumor tissues. However, the effectiveness of PD-1/PD-L1 inhibitors for pMMR/non-MSI-H CRC remains uncertain. Due to the lower prevalence of dMMR/MSI-H in CRC, recent clinical trials have reported combined applications of PD-1/PD-L1 inhibitors with other anti-tumor treatments such as chemotherapy, radiotherapy, and targeted therapy to achieve better therapeutic outcomes. Neoadjuvant therapy, primarily consisting of chemotherapy and radiotherapy, not only downstages the tumor but also provides benefits from local control, thus improving clinical symptoms and quality of life. Integrating immunotherapy into neoadjuvant therapy may alter the treatment approach for potentially resectable or certain metastatic CRC cases. In this article, we focus on the development of neoadjuvant anti-PD-1/PD-L1 therapy and discuss its future prospects for the treatment of CRC.

ARIH1 activates STING-mediated T-cell activation and sensitizes tumors to immune checkpoint blockade

Despite advances in cancer treatment, immune checkpoint blockade (ICB) only achieves complete response in some patients, illustrating the need to identify resistance mechanisms. Using an ICB-insensitive tumor model, here we discover cisplatin enhances the anti-tumor effect of PD-L1 blockade and upregulates the expression of Ariadne RBR E3 ubiquitin-protein ligase 1 (ARIH1) in tumors. Arih1 overexpression promotes cytotoxic T cell infiltration, inhibits tumor growth, and potentiates PD-L1 blockade. ARIH1 mediates ubiquitination and degradation of DNA-PKcs to trigger activation of the STING pathway, which is blocked by the phospho-mimetic mutant T68E/S213D of cGAS protein. Using a high-throughput drug screen, we further identify that ACY738, less cytotoxic than cisplatin, effectively upregulates ARIH1 and activates STING signaling, sensitizing tumors to PD-L1 blockade. Our findings delineate a mechanism that tumors mediate ICB resistance through the loss of ARIH1 and ARIH1-DNA-PKcs-STING signaling and indicate that activating ARIH1 is an effective strategy to improve the efficacy of cancer immunotherapy.

Cisplatin in Liver Cancer Therapy

Hepatocellular carcinoma (HCC) is the most common primary liver tumor and is often diagnosed at an unresectable advanced stage. Systemic chemotherapy as well as transarterial chemoembolization (TACE) and hepatic arterial infusion chemotherapy (HAIC) are used to treat advanced HCC. TACE and HAIC have long been the standard of care for patients with unresectable HCC but are limited to the treatment of intrahepatic lesions. Systemic chemotherapy with doxorubicin or chemohormonal therapy with tamoxifen have also been considered, but neither has demonstrated survival benefits. In the treatment of unresectable advanced HCC, cisplatin is administered transhepatic arterially for local treatment. Subsequently, for cisplatin-refractory cases due to drug resistance, a shift to systemic therapy with a different mechanism of action is expected to produce new antitumor effects. Cisplatin is also used for the treatment of liver tumors other than HCC. This review summarizes the action and resistance mechanism of cisplatin and describes the treatment of the major hepatobiliary cancers for which cisplatin is used as an anticancer agent, with a focus on HCC.

Withaferin A Increases the Effectiveness of Immune Checkpoint Blocker for the Treatment of Non-Small Cell Lung Cancer

Treatment of late-stage lung cancers remains challenging with a five-year survival rate of 8%. Immune checkpoint blockers (ICBs) revolutionized the treatment of non-small cell lung cancer (NSCLC) by reactivating anti-tumor immunity. Despite achieving durable responses, ICBs are effective in only 20% of patients due to immune resistance. Therefore, synergistic combinatorial approaches that overcome immune resistance are currently under investigation. Herein, we studied the immunomodulatory role of Withaferin A (WFA)-a herbal compound-and its effectiveness in combination with an ICB for the treatment of NSCLC. Our in vitro results show that WFA induces immunogenic cell death (ICD) in NSCLC cell lines and increases expression of the programmed death ligand-1 (PD-L1). The administration of N-acetyl cysteine (NAC), a reactive oxygen species (ROS) scavenger, abrogated WFA-induced ICD and PD-L1 upregulation, suggesting the involvement of ROS in this process. Further, we found that a combination of WFA and α-PD-L1 significantly reduced tumor growth in an immunocompetent tumor model. Our results showed that WFA increases CD-8 T-cells and reduces immunosuppressive cells infiltrating the tumor microenvironment. Administration of NAC partially inhibited the anti-tumor response of the combination regimen. In conclusion, our results demonstrate that WFA sensitizes NSCLC to α-PD-L1 in part via activation of ROS.

Cell-in-cell promotes lung cancer malignancy by enhancing glucose metabolism through mitochondria transfer

Heterotypic cell-in-cell structure (CICs) is the definition of the entry of one type of living cells into another type of cell. CICs between immune cells and tumor cells have been found to correlate with malignancy in many cancers. Since tumor immune microenvironment promotes non-small cell lung cancer (NSCLC) progression and drug resistance, we wondered the potential significance of heterotypic CICs in NSCLC. Heterotypic CICs was analyzed by histochemistry in an expanded spectrum of clinical lung cancer tissue specimens. In vitro study was performed using the mouse lung cancer cell line LLC and splenocytes. Our results revealed that CICs formed by lung cancer cells and infiltrated lymphocytes were correlated with malignancy of NSCLC. In addition, we found CICs mediated the transfer of lymphocyte mitochondria to tumor cells, and promoted cancer cell proliferation and anti-cytotoxicity by activating MAPK pathway and up-regulating PD-L1 expression. Furthermore, CICs induces glucose metabolism reprogramming of lung cancer cells by upregulating glucose intake and glycolytic enzyme. Our findings suggest that CICs formed by lung cancer cell and lymphocyte contribute to NSCLC progression and reprogramming of glucose metabolism, and might represent a previously undescribed pathway for drug resistance of NSCLC.

Dual inhibition of IDO1/TDO2 enhances anti-tumor immunity in platinum-resistant non-small cell lung cancer

BACKGROUND

The impact of non-small cell lung cancer (NSCLC) metabolism on the immune microenvironment is not well understood within platinum resistance. We have identified crucial metabolic differences between cisplatin-resistant (CR) and cisplatin-sensitive (CS) NSCLC cells with elevated indoleamine 2,3-dioxygenase-1 (IDO1) activity in CR, recognized by increased kynurenine (KYN) production.

METHODS

Co-culture, syngeneic, and humanize mice models were utilized. C57BL/6 mice were inoculated with either Lewis lung carcinoma mouse cells (LLC) or their platinum-resistant counterpart (LLC-CR) cells. Humanized mice were inoculated with either A (human CS cells) or ALC (human CR cells). Mice were treated with either IDO1 inhibitor or TDO2 (tryptophan 2,3-dioxygenase-2) inhibitor at 200 mg/kg P.O. once a day for 15 days; or with a new-in-class, IDO1/TDO2 dual inhibitor AT-0174 at 170 mg/kg P.O. once a day for 15 days with and without anti-PD1 antibody (10 mg/kg, every 3 days). Immune profiles and KYN and tryptophan (TRP) production were evaluated.

RESULTS

CR tumors exhibited a more highly immunosuppressive environment that debilitated robust anti-tumor immune responses. IDO1-mediated KYN production from CR cells suppressed NKG2D on immune effector natural killer (NK) and CD8⁺ T cells and enhanced immunosuppressive populations of regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Importantly, while selective IDO1 inhibition attenuated CR tumor growth, it concomitantly upregulated the TDO2 enzyme. To overcome the compensatory induction of TDO2 activity, we employed the IDO1/TDO2 dual inhibitor, AT-0174. Dual inhibition of IDO1/TDO2 in CR mice suppressed tumor growth to a greater degree than IDO1 inhibition alone. Significant enhancement in NKG2D frequency on NK and CD8⁺ T cells and a reduction in Tregs and MDSCs were observed following AT-1074 treatment. PD-L1 (programmed death-ligand-1) expression was increased in CR cells; therefore, we assessed dual inhibition + PD1 (programmed cell death protein-1) blocking and report profound anti-tumor growth and improved immunity in CR tumors which in turn extended overall survival in mice.

CONCLUSION

Our study reports the presence of platinum-resistant lung tumors that utilize both IDO1/TDO2 enzymes for survival, and to escape immune surveillance as a consequence of KYN metabolites. We also report early in vivo data in support of the potential therapeutic efficacy of the dual IDO1/TDO2 inhibitor AT-0174 as a part of immuno-therapeutic treatment that disrupts tumor metabolism and enhances anti-tumor immunity.

Modulation of immune checkpoint regulators in interferon γ induced urothelial carcinoma and activated T-lymphocyte cells by cytostatics

Exploring the regulation of co-inhibitory (PD-1, PD-L1, CTLA-4) and co-stimulatory (CD28) genes by chemotherapeutic drugs is important for combined immune checkpoint blockade (ICB) therapy. ICB interferes with T-cell receptor and major histocompatibility complex (MHC) signaling by antibody drugs directed against the co-inhibitors. Here, we analyzed urothelial (T24) cell line with respect to cytokine signaling by interferon γ (IFNG) and the leukemia lymphocyte (Jurkat) cell line with respect to T-cell activation as mimicked by phorbolester and calcium ionophore (pma/iono). Alongside, we considered possible intervention with the chemotherapeutics gemcitabine, cisplatin and vinflunine. Noteworthy, cisplatin significantly induced PD-L1-mRNA in naïve and IFNG treated cells whereas gemcitabine and vinflunine had no effect on PD-L1-mRNA. At the protein level, PD-L1 showed typical induction in IFNG treated cells. In Jurkat cells, cisplatin significantly induced PD-1-mRNA and PD-L1-mRNA. Pma/iono administration did not alter PD-1-mRNA and PD-L1-mRNA but significantly increased CTLA-4-mRNA and CD28-mRNA levels where vinflunine suppressed the CD28-mRNA induction. In sum, we demonstrated that certain cytostatic drugs being relevant for the therapy of urothelial cancer, affect co-inhibitory and co-stimulatory modulators of immune signaling with potential impact for perspective combined ICB therapy of patients. MHC-TCR signaling between antigen presenting cells and T-lymphocytes with co-stimulator (blue) and co-inhibitors (red) and interacting proteins (blank). Co-inhibitory connections are shown by lines and co-stimulatory connections by dotted lines. The inducible or suppressive actions of the drugs (underlined) on the respective targets are indicated.

Efficacy of bronchoscopic intratumoral injection of endostar and cisplatin in lung squamous cell carcinoma patients underwent conventional chemoradiotherapy

Bronchoscopy has been widely used for the therapy of lung cancer. This study aimed to evaluate the therapeutic efficacy and adverse reactions of bronchoscopic intratumoral injection of endostar and cisplatin in patients with lung squamous cell carcinoma (LSCC). A total of 40 LSCC patients who underwent conventional chemoradiotherapy were included in this study, and 20 of them received a bronchoscopic injection of endostar and cisplatin as an additive therapeutic modality (treatment group). The clinical response rate, progression-free survival (PFS), and adverse reactions of the patients were compared and analyzed. The treatment group had better short- and long-term therapeutic efficacy compared to the control group, but no significant differences were observed between the two therapeutic regimens in adverse reactions. Elderly and advanced LSCC patients had worse therapeutic efficacy and a high probability of adverse reactions after the therapy. Collectively, our analysis data demonstrated that the bronchoscopic intratumoral injection of endostar and cisplatin had improved therapeutic efficacy, and the cardiovascular adverse reactions were within the controllable range in the treatment of LSCC in clinical practices.

Ginsenoside Rg3 alleviates the migration, invasion, and angiogenesis of lung cancer cells by inhibiting the expressions of cyclooxygenase-2 and vascular endothelial growth factor

Lung cancer (LC) is a common cancer with high incidence and mortality rates. In recent years, ginsenoside Rg3 (Rg3), a traditional medicine, is widely used for the treatment of LC. Herein, we concentrate on assessing the effect of Rg3 on LC cell migration and invasion. The effects of Rg3 (0, 25, 50, and 100 μg/ml) on the viability, migration, invasion, angiogenesis, and expressions of epithelial-mesenchymal transition (EMT)-related proteins, cyclooxygenase-2 (COX2), and vascular endothelial growth factor (VEGF) of LC cell lines were evaluated by cell counting kit-8 (CCK-8), scratch, transwell, tube formation, and western blot assays. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to assess transfection efficiency. COX2 overexpression plasmid and short hairpin RNA for VEGF (shVEGF) were applied to evaluate whether the effect of Rg3 is related to COX2 and VEGF through rescue assay. In this study, Rg3 significantly dose-dependently suppressed the viability, migration, invasion, angiogenesis, and protein expressions of N-cadherin, vimentin, COX2, and VEGF in H1299 and A549 cells, while promoting the expression of E-cadherin protein. COX2 overexpression markedly reversed the effects of Rg3 on the viability, migration, invasion, angiogenesis, and EMT-related protein expression levels in LC cells; however, such effects of COX2 overexpression were offset by VEGF knockdown. In sum, Rg3 alleviates the migration, invasion, and angiogenesis of LC cells by inhibiting the expressions of COX2 and VEGF.

Clinical and biomarker analyses of sintilimab plus gemcitabine and cisplatin as first-line treatment for patients with advanced biliary tract cancer

The prognosis of biliary tract cancer (BTC) remains unsatisfactory. This single-arm, phase II clinical trial (ChiCTR2000036652) investigated the efficacy, safety, and predictive biomarkers of sintilimab plus gemcitabine and cisplatin as the first-line treatment for patients with advanced BTCs. The primary endpoint was overall survival (OS). Secondary endpoints included toxicities, progression-free survival (PFS), and objective response rate (ORR); multi-omics biomarkers were assessed as exploratory objective. Thirty patients were enrolled and received treatment, the median OS and PFS were 15.9 months and 5.1 months, the ORR was 36.7%. The most common grade 3 or 4 treatment-related adverse events were thrombocytopenia (33.3%), with no reported deaths nor unexpected safety events. Predefined biomarker analysis indicated that patients with homologous recombination repair pathway gene alterations or loss-of-function mutations in chromatin remodeling genes presented better tumor response and survival outcomes. Furthermore, transcriptome analysis revealed a markedly longer PFS and tumor response were associated with higher expression of a 3-gene effector T cell signature or an 18-gene inflamed T cell signature. Sintilimab plus gemcitabine and cisplatin meets pre-specified endpoints and displays acceptable safety profile, multiomics potential predictive biomarkers are identified and warrant further verification.

Switch-maintenance avelumab immunotherapy following first-line chemotherapy for patients with advanced, unresectable or metastatic urothelial carcinoma: the first Japanese real-world evidence from a multicenter study

OBJECTIVE

To develop the first Japanese real-world evidence of switch-maintenance avelumab in advanced, unresectable or metastatic urothelial carcinoma (aUC).

METHODS

A multicenter-derived database registered 505 patients diagnosed with aUC between 2008 and 2021. Of these, 204 patients (40%) were selected and stratified according to the type of therapy used: maintenance avelumab group (27 [5.3%]), second-line (2 L) pembrolizumab group (103 [20%]) and 2 L cytotoxic chemotherapy group (74 [15%]). The progression-free survival and overall survival from the initiation of following therapy were compared. Tumor response was evaluated based on the Response Evaluation Criteria in Solid Tumors guideline v1.1 during the treatment period. A detailed analysis was performed in the maintenance avelumab group to investigate possible factors associated with response to avelumab therapy.

RESULTS

The maintenance avelumab group had a longer overall survival, not progression-free survival, compared with the other two treatment groups. The median treatment-free interval between the last dose of first-line (1 L) chemotherapy and the initiation of avelumab therapy was 6 weeks (range, 3-22). Disease control rate of maintenance avelumab therapy in patients with a treatment-free interval of ≤6 weeks was higher than that in patients with a treatment-free interval of >6 weeks (77 vs 40%, P = 0.029). The patients showing objective response to 1 L chemotherapy were less likely to experience tumor relapse (4 of 19) after the initiation of avelumab therapy compared with those showing stable disease (7 of 8).

CONCLUSIONS

Objective response to 1 L chemotherapy and early induction of maintenance avelumab therapy may be associated with increased benefit from maintenance avelumab therapy.

Perfusion Air Culture of Precision-Cut Tumor Slices: An Ex Vivo System to Evaluate Individual Drug Response under Controlled Culture Conditions

Precision-cut tumor slices (PCTS) maintain tissue heterogeneity concerning different cell types and preserve the tumor microenvironment (TME). Typically, PCTS are cultured statically on a filter support at an air-liquid interface, which gives rise to intra-slice gradients during culture. To overcome this problem, we developed a perfusion air culture (PAC) system that can provide a continuous and controlled oxygen medium, and drug supply. This makes it an adaptable ex vivo system for evaluating drug responses in a tissue-specific microenvironment. PCTS from mouse xenografts (MCF-7, H1437) and primary human ovarian tumors (primary OV) cultured in the PAC system maintained the morphology, proliferation, and TME for more than 7 days, and no intra-slice gradients were observed. Cultured PCTS were analyzed for DNA damage, apoptosis, and transcriptional biomarkers for the cellular stress response. For the primary OV slices, cisplatin treatment induced a diverse increase in the cleavage of caspase-3 and PD-L1 expression, indicating a heterogeneous response to drug treatment between patients. Immune cells were preserved throughout the culturing period, indicating that immune therapy can be analyzed. The novel PAC system is suitable for assessing individual drug responses and can thus be used as a preclinical model to predict in vivo therapy responses.

Prognostic and predictive biomarkers for immunotherapy in advanced renal cell carcinoma

The therapeutic algorithm of renal cell carcinoma has been revolutionized by the approval of immunotherapy agents by regulatory agencies. However, objective and durable responses are still not observed in a large number of patients, and prognostic and predictive biomarkers for immunotherapy response are urgently needed. Prognostic models used in clinical practice are based on clinical and laboratory factors (such as hypercalcaemia, neutrophil count or Karnofsky Performance Status), but, with progress in molecular biology and genome sequencing techniques, new renal cell carcinoma molecular features that might improve disease course and outcomes prediction have been highlighted. An implementation of current models is needed to improve the accuracy of prognosis in the immuno-oncology era. Moreover, several potential biomarkers are currently under evaluation, but effective markers to select patients who might benefit from immunotherapy and to guide therapeutic strategies are still far from validation.

Doxorubicin-An Agent with Multiple Mechanisms of Anticancer Activity

Doxorubicin (DOX) constitutes the major constituent of anti-cancer treatment regimens currently in clinical use. However, the precise mechanisms of DOX's action are not fully understood. Emerging evidence points to the pleiotropic anticancer activity of DOX, including its contribution to DNA damage, reactive oxygen species (ROS) production, apoptosis, senescence, autophagy, ferroptosis, and pyroptosis induction, as well as its immunomodulatory role. This review aims to collect information on the anticancer mechanisms of DOX as well as its influence on anti-tumor immune response, providing a rationale behind the importance of DOX in modern cancer therapy.

Effect of Radio-Chemotherapy on PD-L1 Immunohistochemical Expression in Head and Neck Squamous Cell Carcinoma

BACKGROUND

Programmed death-ligand 1 (PD-L1) checkpoint inhibitors represent a mainstay of therapy in head and neck squamous cell cancer (HNSCC). However, little is known about the influence of combined therapy on PD-L1 expression. The study aims to gather evidence on this topic.

METHODS

A systematic search was carried out in electronic databases Pubmed-MEDLINE and Embase to retrieve studies on the comparison of PD-L1 expression before and after conventional therapy. Data were extracted and a quantitative analysis with pooled odds ratios (ORs) was performed when applicable.

RESULTS

Of 5688 items, 15 were finally included. Only a minority of studies assessed PD-L1 with the recommended combined positive score (CPS). The results are highly heterogeneous, with some studies reporting an increase in PD-L1 expression and others reporting a decrease. Three studies allowed for quantitative analysis and showed a pooled OR of 0.49 (CI 0.27-0.90).

CONCLUSIONS

From the present evidence, a clear conclusion towards an increase or decrease in PD-L1 expression after combined therapy cannot be drawn, but even with few studies available, a trend towards an increase in expression in tumor cells at a cutoff of 1% can be noted in patients undergoing platinum-based therapy. Future studies will provide more robust data on the effect of combined therapy on PD-L1 expression.

Drug-loaded microbubble delivery system to enhance PD-L1 blockade immunotherapy with remodeling immune microenvironment

BACKGROUND

Although programmed cell death protein 1 (PD-1)/ programmed cell death-ligand protein 1 (PD-L1) checkpoint blockade immunotherapy demonstrates great promise in cancer treatment, poor infiltration of T cells resulted from tumor immunosuppressive microenvironment (TIME) and insufficient accumulation of anti-PD-L1 (αPD-L1) in tumor sites diminish the immune response. Herein, we reported a drug-loaded microbubble delivery system to overcome these obstacles and enhance PD-L1 blockade immunotherapy.

METHODS

Docetaxel (DTX) and imiquimod (R837)-loaded microbubbles (RD@MBs) were synthesized via a typical rotary evaporation method combined with mechanical oscillation. The targeted release of drugs was achieved by using the directional "bursting" capability of ultrasound-targeted microbubble destruction (UTMD) technology. The antitumor immune response by RD@MBs combining αPD-L1 were evaluated on 4T1 and CT26 tumor models.

RESULTS

The dying tumor cells induced by DTX release tumor-associated antigens (TAAs), together with R837, promoted the activation, proliferation and recruitment of T cells. Besides, UTMD technology and DTX enhanced the accumulation of αPD-L1 in tumor sites. Moreover, RD@MBs remolded TIME, including the polarization of M2-phenotype tumor-associated macrophages (TAMs) to M1-phenotype, and reduction of myeloid-derived suppressor cells (MDSCs). The RD@MBs + αPD-L1 synergistic therapy not only effectively inhibited the growth of primary tumors, but also significantly inhibited the mimic distant tumors as well as lung metastases.

CONCLUSION

PD-L1 blockade immunotherapy was enhanced by RD@MBs delivery system.

PD-1/PD-L1 and DNA Damage Response in Cancer

The application of immunotherapy for cancer treatment is rapidly becoming more widespread. Immunotherapeutic agents are frequently combined with various types of treatments to obtain a more durable antitumor clinical response in patients who have developed resistance to monotherapy. Chemotherapeutic drugs that induce DNA damage and trigger DNA damage response (DDR) frequently induce an increase in the expression of the programmed death ligand-1 (PD-L1) that can be employed by cancer cells to avoid immune surveillance. PD-L1 exposed on cancer cells can in turn be targeted to re-establish the immune-reactive tumor microenvironment, which ultimately increases the tumor's susceptibility to combined therapies. Here we review the recent advances in how the DDR regulates PD-L1 expression and point out the effect of etoposide, irinotecan, and platinum compounds on the anti-tumor immune response.

Add-On Effect of Hemagglutinating Virus of Japan Envelope Combined with Chemotherapy or Immune Checkpoint Inhibitor against Malignant Pleural Mesothelioma: An In Vivo Study

Malignant pleural mesothelioma (MPM) is a refractory tumor because most of the lesions are already disseminated at diagnosis. Previously, the main treatment for MPM was combination chemotherapy. However, recently, immune checkpoint inhibitors (ICIs) are also used. For better efficacy of MPM treatment, we focused on hemagglutinating virus of Japan envelope (HVJ-E), which activates antitumor immunity and induces tumor-specific cell death. In this paper, we aimed to determine whether HVJ-E as a single agent therapy or in combination with chemotherapy or ICIs is effective in MPM bearing mouse. We confirmed its antitumor efficacy in MPM-bearing mouse. HVJ-E significantly prolonged the survival of human MPM-bearing mouse compared to that of control mouse and when combined with CDDP. This efficacy was lost in NOD-SCID mouse, suggesting that activation of innate immunity by HVJ-E was related to the survival rate. HVJ-E also showed antitumor efficacy in murine MPM-bearing mouse. The combination of chemotherapy and HVJ-E caused a significant increase in cytotoxic T cells (CTLs) compared to chemotherapy alone, suggesting that not only innate immunity activated by HVJ-E but also the increase in CTLs contributed to improved survival. The combination of anti-PD-1 antibody and HVJ-E significantly prolonged the survival rate of murine MPM-bearing mouse. Further, HVJ-E might have exhibited antitumor effects by maintaining immunogenicity against tumors. We believe that HVJ-E may be a beneficial therapy to improve MPM treatment in the future.