How Chemotherapy Affects the Tumor Immune Microenvironment: A Narrative Review

Temozolomide monotherapy versus combination therapies in melanoma: a meta-analysis of efficacy and safety

Temozolomide is used in melanoma therapy, but the comparative efficacy and safety of monotherapy vs combination therapies are unclear. This meta-analysis evaluates temozolomide monotherapy vs combination therapies in melanoma patients. PubMed, Embase, and Cochrane Library were searched up to August 2024 for studies comparing temozolomide monotherapy with combination therapies in melanoma. Primary outcomes were 1-year survival and objective response rates (RR); secondary outcomes included hematologic and non-hematologic toxicities. Data were pooled using risk ratios with 95% confidence intervals (CIs). Seven studies were included. Combination therapies improved objective RR over temozolomide monotherapy (risk ratio 0.68, 95% CI: 0.53-0.88). One-year survival did not differ significantly between groups (risk ratio 0.81, 95% CI: 0.59-1.12). Temozolomide monotherapy was associated with reduced incidence of leukopenia (risk ratio 0.54, 95% CI: 0.30-0.95). Adding interferon-alpha (IFN-α) to temozolomide significantly improved 1-year survival (risk ratio 0.54, 95% CI: 0.35-0.84) and objective RR (risk ratio 0.57, 95% CI: 0.42-0.78) compared to temozolomide alone, without significantly increasing toxicity. Combination therapies enhance objective RR over temozolomide monotherapy, with similar 1-year survival. Temozolomide monotherapy offers a better hematologic safety profile. Combining temozolomide with IFN-α significantly improves survival and RR without increasing toxicity. Clinicians should balance efficacy and safety when choosing melanoma treatments.

Unveiling the Synergistic Potential: Bispecific Antibodies in Conjunction with Chemotherapy for Advanced Non-Small-Cell Lung Cancer Treatment

Lung cancer remains the leading cause of cancer-related mortality worldwide, with non-small-cell lung cancer (NSCLC) accounting for the majority of the cases. Despite advancements in targeted therapies and immunotherapies, many patients still rely on chemotherapy, highlighting the need for innovative treatment strategies. Bispecific antibodies (bsAbs), which feature two distinct binding sites capable of targeting different antigens, have emerged as a promising therapeutic approach, particularly in combination with chemotherapy. This review explores the scientific evolution and clinical application of bsAbs in NSCLC, focusing on their synergistic potential with chemotherapy. BsAbs, such as amivantamab, which targets EGFR and MET, have demonstrated significant efficacy in clinical trials, particularly in patients with EGFR mutations. The combination of bsAbs with chemotherapy enhances immune-mediated tumor destruction by modulating the tumor microenvironment and overcoming resistance mechanisms. Recent clinical trials have shown improved progression-free survival and overall survival when bsAbs such as amivantamab are combined with chemotherapy, underscoring their potential to transform NSCLC treatment. Many other clinical trials are underway that are evaluating newer bsAbs, such as ivonescimab, which targets PD1 and VEGF. This review also discusses ongoing clinical trials investigating various bsAbs targeting EGFR, PD-1, PD-L1, HER2, and other pathways, highlighting the future directions of bsAb-based therapies. As the field evolves, bsAbs are poised to become a cornerstone of multimodal NSCLC treatment, offering more effective and personalized therapeutic options for patients with advanced disease.

Chemotherapy Response Score (CRS): A comprehensive review of its prognostic and predictive value in High-Grade Serous Carcinoma (HGSC)

Ovarian carcinoma, the second most common gynecological cancer in Western countries, is frequently diagnosed at advanced stages, necessitating complex treatment strategies. While cytoreductive surgery remains the standard for improving survival, neoadjuvant chemotherapy (NACT) has become essential for cases unsuitable for immediate surgery, aiming to reduce tumor burden preoperatively. Introduced in 2015, the Chemotherapy Response Score (CRS) is now a key histopathological tool for assessing response to NACT, stratifying patients into three response categories. CRS3 is associated with improved progression-free survival (PFS) and overall survival (OS), while CRS1 and CRS2 are linked to poorer outcomes. Validated across clinical cohorts, CRS has proven valuable not only as a prognostic tool but also as a predictor for molecular-targeted therapies, such as PARP inhibitors, especially in BRCA wild-type patients. Studies also suggest a potential role for CRS in guiding the use of PD-L1 inhibitors, especially in partial responders (CRS1 and CRS2), where immunotherapy may complement chemotherapy. In the present paper we exlored the actual knowledge on CRS scoring for ovarian carcinoma. Diagnostic and prognostic implications of CRS as well as its correlation with therapeutic response and other biomarkers are discussed.

Successful repositioning of mertansine for improved chemotherapy by combining a polymer prodrug approach and PET imaging

Mertansine (DM1), a potent tumor-killing maytansinoid, requires conjugation to antibodies or incorporation into nanocarriers due to its high toxicity. However, these carriers often result in undesirable biodistribution, leading to rapid and long-term accumulation in the kidneys or liver and potentially increased toxicity. To overcome this limitation, we used the hydrophilic, biocompatible, and stealth properties of polyacrylamide (PAAm) as a scaffold to develop water-soluble PAAm-DM1 polymer prodrugs, leveraging PAAm's previous success in delivering paclitaxel via subcutaneous administration. To monitor distribution and predict efficacy, we have imparted Positron Emission Tomography (PET) imaging capabilities to well-defined PAAm-DM1 polymer prodrugs. Our studies demonstrated the same tumor accumulation and the same distribution of PAAm-DM1 in the main organs such as liver, kidneys muscle, regardless of delivery route (subcutaneous or intravenous). Interestingly, tumor accumulation of PAAm-DM1 was primarily driven by passive accumulation, as indicated by PET imaging, without significantly altering treatment efficacy. This suggests complex mechanisms, possibly involving immune system interactions by influencing notably the metabolism and clearance. To enhance therapeutic outcomes, we combined the polymer prodrug with immunotherapy, specifically anti-CTLA4. Our findings highlight the promising potential of PAAm-DM1, offering a novel formulation strategy for DM1 in cancer therapy.

Roles of CDK12 mutations in PCa development and treatment

Prostate cancer (PCa) is one of the most common cancers in men, and cyclin-dependent kinase 12 (CDK12) is emerging as a novel star player in the PCa tumorigenesis and progression to castration-resistant prostate cancer (CRPC). In PCa, CDK12 alterations are mostly loss-of-function mutations featuring intronic polyadenylation (IPA), focal tandem duplications (FTDs), and R-loops formation and transcription-replication conflicts (TRCs). The occurrence of IPA can result in homologous recombination deficiency (HRD) and androgen receptor (AR) variation. FTDs induce neoantigens and increase the expression of the AR, MYC, and other hotspot- associated genes. R-loops lead to TRCs and influence various cellular processes, including gene expression and genome stability. Due to the poor prognosis of CDK12-mutant PCa patients and the mediocre response to classic standard therapies, HRD and increased neoantigen levels have provided clinicians with new insights into alternative systematic treatments for this novel PCa phenotype. In this review, we summarize the roles of CDK12 mutations in PCa and discuss their clinical value, suggesting that CDK12 potentially represents a target for further research and the development of clinical strategies for PCa.

PD-1/PD-L1 Inhibitors Increase Pathological Complete Response in Locally Advanced Gastric Cancer: A Meta-analysis and Trial Sequential Analysis

BACKGROUND AND OBJECTIVE

Gastric cancer (GC) remains a leading cause of morbidity and mortality worldwide. The current standard of care involves neoadjuvant chemotherapy (NACT) followed by radical gastrectomy. This study aims to evaluate the efficacy of neoadjuvant therapy with PD-1/PD-L1 inhibitors in comparison to chemotherapy alone for patients with locally advanced gastric cancer (LAGC).

METHODS

We conducted a systematic search of PubMed, Web of Science, and Embase to identify studies examining the addition of PD-1/PD-L1 inhibitors to neoadjuvant therapy for LAGC. Odds ratios (OR) were calculated for binary outcomes, such as pathological complete response (pCR), with corresponding 95% confidence intervals (CI).

RESULTS

Seven studies were included, encompassing a total of 1772 patients. Baseline median age ranged from 31 to 75 years. Most patients had an ECOG performance status score of 0 (942 patients), while 294 had an ECOG score of 1. The estimated pCR (OR 5.94, 95% CI 3.98-8.87; p < 0.000001) significantly favored the PD-1/PD-L1 inhibitors combined with chemotherapy over chemotherapy alone. Additionally, the incidence of certain adverse events increased significantly in the intervention group, including any-grade hypothyroidism (OR 4.55, 95% CI 2.27-9.10; p = 0.000019) and rash (OR 1.74, 95% CI 1.10-2.76; p = 0.017). Conversely, the control group showed a statistically significant lower incidence of grade ≥ 3 fatigue (OR 2.80, 95% CI 1.15-6.85; p = 0.024) compared to the intervention group.

CONCLUSION

This systematic review and meta-analysis indicate that the addition of PD-1/PD-L1 inhibitors to neoadjuvant chemotherapy is associated with a higher pathological complete response rate compared to chemotherapy alone in patients with locally advanced gastric cancer.

Alteration of PD-L1 (SP142) status after neoadjuvant chemotherapy and its clinical significance in triple-negative breast cancer

PURPOSE

The tumor immune microenvironment can change after neoadjuvant chemotherapy (NAC) for triple-negative breast cancer (TNBC). We aimed to investigate the effects of NAC on PD-L1 (SP142) status and its clinical significance in TNBC.

METHODS

Paired samples of biopsy and resection specimens were collected from 182 patients with TNBC before and after NAC. PD-L1 (SP142) expression in immune cells in pre- and post-NAC breast cancer samples and the changes between them were analyzed, along with their relationships with the clinicopathological features and clinical outcomes of the patients.

RESULTS

Of the 182 patients, 61 (33.5%) achieved pathologic complete response (pCR) after NAC. PD-L1 (SP142) positivity, defined as immune cell staining in ≥ 1% of tumor area, was a predictor for pCR. PD-L1-positive immune cells significantly increased after NAC (2.8% to 5.2% on average) in 109 patients with measurable residual disease. Alteration of PD-L1 status was observed in 24 (22.0%) of the 109 patients with measurable residual tumors after NAC, and all PD-L1 status-converted patients, except one, revealed negative-to-positive conversion. Regarding chemotherapeutic agents, the use of platinum agents was associated with a significant increase in PD-L1-positive immune cells after NAC. In survival analyses, a positive PD-L1 status after NAC and increase of PD-L1-positive immune cells after NAC were associated with better recurrence-free survival of the patients.

CONCLUSION

PD-L1 (SP142) status changes after NAC, mostly as a positive conversion. As PD-L1 (SP142) status can convey prognostic and predictive information, it needs to be tested before and after NAC.

Magnetic resonance imaging radiomics-based prediction of severe inflammatory response in locally advanced rectal cancer patients after neoadjuvant radiochemotherapy

PURPOSE

To predict severe inflammatory response after neoadjuvant radiochemotherapy in locally advanced rectal cancer (RC) patients using magnetic resonance imaging (MRI) radiomics models.

METHODS

This retrospective study included patients who underwent radical surgery for RC cancer after neoadjuvant radiochemotherapy between July 2017 and December 2019 at XXX Hospital. MRI radiomics features were extracted from T2WI images before (pre-nRCT-RF) and after (post-nRCT-RF) neoadjuvant radiochemotherapy, and the variation of radiomics features before and after neoadjuvant radiochemotherapy (delta-RF) were calculated. Eight, eight, and five most relevant features were identified for pre-nRCT-RF, post-nRCT-RF, and delta-RF, respectively.

RESULTS

Eighty-six patients were included and randomized 3:1 to the training and test set (n = 65 and n = 21, respectively). The prediction model based on delta-RF had areas under the curve (AUCs) of 0.80 and 0.85 in the training and test set, respectively. A higher rate of difficult operations was observed in patients with severe inflammation (65.5% vs. 42.9%, P = 0.045).

CONCLUSION

The prediction model based on MRI delta-RF may be a useful tool for predicting severe inflammatory response after neoadjuvant radiochemotherapy in locally advanced RC patients.

Real-World Assessment of Recommended COVID-19 Vaccination Waiting Period after Chemotherapy

There is a knowledge gap concerning the proper timing for COVID-19 vaccination in cancer patients undergoing chemotherapy. We aimed to evaluate the suitability of the guidelines that recommend waiting at least three months after undergoing chemotherapy before receiving a COVID-19 vaccine. This retrospective cohort study used aggregated data from the TriNetX US Collaboratory network. Participants were grouped into two groups based on the interval between chemotherapy and vaccination. The primary outcome assessed was infection risks, including COVID-19; skin, intra-abdominal, and urinary tract infections; pneumonia; and sepsis. Secondary measures included healthcare utilization and all causes of mortality. Kaplan-Meier analysis and the Cox proportional hazard model were used to calculate the cumulative incidence and hazard ratio (HR) and 95% confidence intervals for the outcomes. The proportional hazard assumption was tested with the generalized Schoenfeld approach. Four subgroup analyses (cancer type, vaccine brand, sex, age) were conducted. Sensitivity analyses were performed to account for competing risks and explore three distinct time intervals. Patients receiving a vaccine within three months after chemotherapy had a higher risk of COVID-19 infection (HR: 1.428, 95% CI: 1.035-1.970), urinary tract infection (HR: 1.477, 95% CI: 1.083-2.014), and sepsis (HR: 1.854, 95% CI: 1.091-3.152) compared to those who adhered to the recommendations. Hospital inpatient service utilization risk was also significantly elevated for the within three months group (HR: 1.692, 95% CI: 1.354-2.115). Adhering to a three-month post-chemotherapy waiting period reduces infection and healthcare utilization risks for cancer patients receiving a COVID-19 vaccine.

Effect of Neoadjuvant Chemotherapy on Tumor-Infiltrating Lymphocytes in Resectable Gastric Cancer: Analysis from a Western Academic Center

Tumor-infiltrating lymphocytes (TILs) are an emerging biomarker predictive of response to immunotherapy across a spectrum of solid organ malignancies. The characterization of TILs in gastric cancer (GC) treated with contemporary, multiagent neoadjuvant chemotherapy (NAC) is understudied. In this retrospective investigation, we analyzed the degree of infiltration, phenotype, and spatial distribution of TILs via immunohistochemistry within resected GC specimens treated with or without NAC at a Western center. We hypothesized that NAC executes immunostimulatory roles, as evidenced by an increased number of anti-tumor TILs in the tumor microenvironment. We found significantly elevated levels of conventional and memory CD8+ T cells, as well as total TILs (CD4+, CD8+, Treg, B cells), within chemotherapy-treated tumors compared with chemotherapy-naïve specimens. We also revealed important associations between survival and pathologic responses with enhanced TIL infiltration. Taken together, our findings advocate for an immunostimulatory role of chemotherapy and underscore the potential synergistic effect of combining chemotherapy with immunotherapy in resectable gastric cancer.

Hsp90 inhibition leads to an increase in surface expression of multiple immunological receptors in cancer cells

Heat shock protein 90 (Hsp90) is a molecular chaperone important for maintaining protein homeostasis (proteostasis) in the cell. Hsp90 inhibitors are being explored as cancer therapeutics because of their ability to disrupt proteostasis. Inhibiting Hsp90 increases surface density of the immunological receptor Major Histocompatibility Complex 1 (MHC1). Here we show that this increase occurs across multiple cancer cell lines and with both cytosol-specific and pan-Hsp90 inhibitors. We demonstrate that Hsp90 inhibition also alters surface expression of both IFNGR and PD-L1, two additional immunological receptors that play a significant role in anti-tumour or anti-immune activity in the tumour microenvironment. Hsp90 also negatively regulates IFN-γ activity in cancer cells, suggesting it has a unique role in mediating the immune system's response to cancer. Our data suggests a strong link between Hsp90 activity and the pathways that govern anti-tumour immunity. This highlights the potential for the use of an Hsp90 inhibitor in combination with another currently available cancer treatment, immune checkpoint blockade therapy, which works to prevent immune evasion of cancer cells. Combination checkpoint inhibitor therapy and the use of an Hsp90 inhibitor may potentiate the therapeutic benefits of both treatments and improve prognosis for cancer patients.

Sintilimab with two cycles of chemotherapy for the treatment of advanced squamous non-small cell lung cancer: a phase 2 clinical trial

This was a single-arm, multicenter phase 2 clinical trial (ChiCTR1900021726) involving advanced squamous non-small cell lung cancer (sq-NSCLC) patients undergoing 2 cycles of nab-paclitaxel/carboplatin and sintilimab (anti-PD-1), followed by sintilimab maintenance therapy. The median progression-free survival (PFS) was 11.4 months (95% CI: 6.7-18.1), which met the pre-specified primary endpoint. Secondary endpoints included objective response rate reaching 70.5% and a disease control rate of 93.2%, with a median duration of response of 13.6 months [95% CI: 7.0-not evaluable (NE)]. The median overall survival was 27.2 months (95% CI: 20.2-NE) with treatment-related adverse events grades ≥3 occurring in 10.9% of patients. Predefined exploratory endpoints comprised relationships between biomarkers and treatment efficacy, and the association between circulating tumor DNA (ctDNA) dynamics and PFS. Biomarker analysis revealed that the breast cancer gene 2, BMP/Retinoic Acid Inducible Neural Specific 3, F-box/WD repeat-containing protein 7, tyrosine-protein kinase KIT and retinoblastoma 1 abnormalities led to shorter PFS, while ctDNA negative at baseline or clearance at 2 cycles of treatment was associated with longer PFS (18.1 vs. 4.3 months). Taken together, sintilimab in combination with 2 cycles of nab-paclitaxel/carboplatin treatment produced encouraging PFS and better tolerability as first-line treatment for advanced sq-NSCLC.

Evaluation of the Immunosafety of Cucurbit[n]uril In Vivo

Cucurbiturils are a family of macrocyclic oligomers capable of forming host-guest complexes with various molecules. Due to noncovalent binding to drug molecules and low toxicity, cucurbiturils has been extensively investigated as potential carriers for drug delivery. However, the immune system's interactions with different drug carriers, including cucurbiturils, are still under investigation. In this study, we focused on cucurbiturils' immunosafety and immunomodulation properties in vivo. We measured blood counts and lymphocyte subpopulations in blood, spleen, and bone marrow, and assessed the in vivo toxicity to spleen and bone marrow cells after intraperitoneal administration to BALB/c mice. When assessing the effect of cucurbit[6]uril on blood parameters after three intraperitoneal injections within a week in laboratory animals, a decrease in white blood cells was found in mice after injections of cucurbit[6]util, but the observed decrease in the number of white blood cells was within the normal range. At the same time, cucurbit[7]uril and cucurbit[8]uril did not affect the leukocyte counts of mice after three injections. Changes in the number of platelets, erythrocytes, and monocytes, as well as in several other indicators, such as hematocrit or erythrocyte volumetric dispersion, were not detected. We show that cucurbiturils do not have immunotoxicity in vivo, with the exception of a cytotoxic effect on spleen cells after сucurbit[7]uril administration at a high dosage. We also evaluated the effect of cucurbiturils on cellular and humoral immune responses. We founded that cucurbiturils in high concentrations affect the immune system in vivo, and the action of various cucurbiturils differs in different homologues, which is apparently associated with different interactions in the internal environment of the body.

Overcoming Resistance Mechanisms to Immune Checkpoint Inhibitors: Leveraging the Anti-Tumor Immune Response

As far back as 3000 years ago, the immune system was observed to play a role in mediating tumor regression. Since then, many strategies have been developed to leverage the anti-tumor immune response. However, while many patients respond to ICIs up front some do not, and many of those that do eventually experience tumor progression. Currently, there are several predictive biomarkers of the immune checkpoint inhibitor response; however, no one test appears to be universally predictive and their application varies by disease site. There are many ways in which cancer cells develop primary or acquired resistance to immune checkpoint inhibitors. Efforts to reverse resistance include ways to combat T cell exhaustion, reprogram the tumor microenvironment, increase the availability of tumor neo-antigens, target alternative immune checkpoints, restore a normal/healthy patient gut microbiome, oncolytic viruses and tumor vaccines. The most studied and most promising methods include combining ICIs with therapies targeting alternative immune checkpoints and restoring a normal/healthy patient gut microbiome. This review will discuss T cell-mediated immunity, how this is leveraged by modern immunotherapy to treat cancer and mechanisms of immune checkpoint inhibitor resistance, while highlighting strategies to overcome primary and secondary resistance mechanisms.

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.

Progress in research on tumor microenvironment-based spatial omics technologies

Spatial omics technology integrates the concept of space into omics research and retains the spatial information of tissues or organs while obtaining molecular information. It is characterized by the ability to visualize changes in molecular information and yields intuitive and vivid visual results. Spatial omics technologies include spatial transcriptomics, spatial proteomics, spatial metabolomics, and other technologies, the most widely used of which are spatial transcriptomics and spatial proteomics. The tumor microenvironment refers to the surrounding microenvironment in which tumor cells exist, including the surrounding blood vessels, immune cells, fibroblasts, bone marrow-derived inflammatory cells, various signaling molecules, and extracellular matrix. A key issue in modern tumor biology is the application of spatial omics to the study of the tumor microenvironment, which can reveal problems that conventional research techniques cannot, potentially leading to the development of novel therapeutic agents for cancer. This paper summarizes the progress of research on spatial transcriptomics and spatial proteomics technologies for characterizing the tumor immune microenvironment.

Synergistic chemo-photo anticancer therapy by using reversible Diels-Alder dynamic covalent bond mediated polyprodrug amphiphiles and immunoactivation investigation

Highly efficient endocytosis and multi-approach integrated therapeutic tactics are important factors in oncotherapy. With the aid of thermally reversible furan-maleimide dynamic covalent bonds and the "polyprodrug amphiphiles" concept, thermo- and reduction-responsive PEG(-COOH)Fu/MI(-SS-)CPT copolymers were fabricated by the Diels-Alder (D-A) coupling of hydrophilic Fu(-COOH)-PEG and hydrophobic MI(-SS-)-CPT building blocks. The copolymers could self-assemble to form composite nanoparticles with a photothermal conversion reagent (IR780) and maintain excellent stability. In the in vitro simulated environments, the composite nanoparticles could detach Fu(-COOH)-PEG chains by a retro-D-A reaction upon near-infrared light (NIR) irradiation and reduce the size to facilitate endocytosis. Once in the intracellular environment, glutathione (GSH) could trigger a cascade reaction to release active CPT drugs to achieve chemotherapy, which could be further promoted by NIR light induced photothermal therapy. The in vivo mouse tumor model experiments demonstrated that these nanoparticles had an excellent therapeutic effect on solid tumors and inhibited their recurrence. Not only that, the synergistic chemical and optical therapy induced body immune response was also systematically evaluated; the maturation of dendritic cells, the proliferation of T cells, the increase of high mobility group box protein 1, and the decrease of immunosuppressive regulatory T cells confirmed that such synergistic therapy could effectively provide immune protection to the body. We believe such in situ generation of small-sized therapeutic units brought by a dynamically reversible D-A reaction could expand the pathway to design next generation drug delivery systems possessing superior design philosophy and excellent practice effects compared to currently available ones.

Tumor Immune Microenvironment Heterogeneity at the Invasion Front and Tumor Center in Oral Squamous Cell Carcinoma as a Perspective of Managing This Cancer Entity

BACKGROUND

Evaluating the tumor microenvironment and its influence on clinical management and therapy response is becoming increasingly important. However, only a few studies deal with the spatial distribution of immune cells within the tumor. This study aimed to describe the topology of immune cells in the microenvironment of oral squamous cell carcinoma (OSCC) sectioned by tumor invasion front and tumor center and to test their prognostic relevance regarding patient survival.

METHODS

A total of 55 OSCC patient specimens were collected retrospectively. The cancer tissue was immunohistochemically stained using an automated tissue stainer Ventana Benchmark Ultra (Roche) and analyzed using discrete expression marker profiles on immune cells. We investigated CD4+ lymphocytes, CD8+ lymphocytes, CD68+ macrophages, CD163+ macrophages, and M1 macrophages regarding their spatial distribution.

RESULTS

The statistical analysis revealed that the quantity and distribution of CD4+ (p = 0.007), CD8+ (p < 0.001), CD68+ (p < 0.001), CD163+ cells (p = 0.004), and M1 (p < 0.001) macrophages were significantly higher at the invasion front compared to the tumor center in all observed cases. However, high and low immune cell counts in the tumor center and invasion front were not associated with overall survival.

CONCLUSION

Our results show two distinct immune microenvironments of the tumor center compared to the invasion front. Future studies are needed to explore how these results can be leveraged to improve patient therapy and outcome.

Temozolomide combined with ipilimumab plus nivolumab enhances T cell killing of MGMT-expressing, MSS colorectal cancer cells

Colorectal cancer (CRC) is the third most frequently diagnosed cancer and third-deadliest cancer globally. Over 95% of patients with metastatic CRC have tumors that are microsatellite stable (MSS) and do not respond to immune checkpoint inhibitors (ICI). Results from the 2022 MAYA clinical trial suggest that the DNA-damaging agent temozolomide (TMZ), which is usually used to treat glioblastoma (GBM), sensitizes patients with MSS, MGMT-silenced CRC to ipilimumab + nivolumab ICI. The benefit of adding ipilimumab + nivolumab to TMZ and the impact of MGMT silencing remain unclear. Here, we aimed to determine in a controlled in vitro system if adding ICI to TMZ enhances T cell killing of MSS CRC cells. We also aimed to determine the contribution of MGMT to this response. Western blot analysis indicated that CRC cells (n = 4) had significantly elevated MGMT expression as compared to GBM cells (n = 4) likely due to MGMT promoter methylation in GBM cells. In line with this, CRC cells were slightly more resistant to TMZ compared to GBM cells after five days of treatment. TMZ + ICI sensitized MGMT-expressing, MSS CRC cells to T cell killing. TMZ alone did not enhance T cell killing of MSS or MSI CRC cells but did slightly enhance T cell killing of T98G GBM cells. Our results indicate that TMZ sensitizes MSS, MGMT-expressing CRC cells to ipilimumab + nivolumab ICI. Importantly, this suggests that TMZ-mediated sensitization to ipilimumab + nivolumab appears independent of MGMT status and the patient cohort that may benefit from TMZ + ipilimumab + nivolumab may be expanded to CRC patients with MGMT-expressing, MSS tumors.

Immune checkpoint blockade for locally advanced or recurrent/metastatic cervical cancer: An update on clinical data

Immunotherapy has shown great promise in the field of oncology, and recent clinical trials have illustrated that immune checkpoint blockade (ICB) is safe and effective at treating a range of tumor types. Cervical cancer (CC) is the fourth most common malignancy in women. However, first-line treatments for locally advanced cervical cancer (LACC) and recurrent/metastatic (R/M) CC have limited efficacy. Thus, it is necessary to explore new treatment approaches. The National Comprehensive Cancer Network (NCCN) currently recommends pembrolizumab, a programmed cell death protein 1 (PD-1) monoclonal antibody, as a first line therapy for individuals with R/M CC. This study reviews the progress of ICB therapy for LACC and R/M CC and describes the current status of the combination of ICB therapy and other therapeutic modalities, including radiotherapy, chemotherapy, targeted therapy, and other immunotherapies. The focus is placed on studies published since 2018 with the aim of highlighting novel CC-specific immunotherapeutic approaches and treatment targets.