Pan-drug and drug-specific mechanisms of 5-FU, irinotecan (CPT-11), oxaliplatin, and cisplatin identified by comparison of transcriptomic and cytokine responses of colorectal cancer cells

Unlocking the Potential of Therapy-Induced Cytokine Responses: Illuminating New Pathways in Cancer Precision Medicine

Precision cancer medicine primarily aims to identify individual patient genomic variations and exploit vulnerabilities in cancer cells to select suitable patients for specific drugs. These genomic features are commonly determined by gene sequencing prior to therapy, to identify individuals who would be most responsive. This precision approach in cancer therapeutics remains a powerful tool that benefits a smaller pool of patients, sparing others from unnecessary treatments. A limitation of this approach is that proteins, not genes, are the ultimate effectors of biological functions, and therefore the targets of therapeutics. An additional dimension in precision medicine that considers an individual's cytokine response to cancer therapeutics is proposed. Cytokine responses to therapy are multifactorial and vary among individuals. Thus, precision is dictated by the nature and magnitude of cytokine responses in the tumor microenvironment exposed to therapy. This review highlights cytokine responses as modules for precision medicine in cancer therapy, including potential challenges. For solid tumors, both detectability of cytokines in tissue fluids and their being amenable to routine sensitive analyses could address the difficulty of specimen collection for diagnosis and monitoring. Therefore, in precision cancer medicine, cytokines offer rational targets that can be utilized to enhance the efficacy of cancer therapy.

The role of p53 in anti-tumor immunity and response to immunotherapy

p53 is a transcription factor that regulates the expression of genes involved in tumor suppression. p53 mutations mediate tumorigenesis and occur in approximately 50% of human cancers. p53 regulates hundreds of target genes that induce various cell fates including apoptosis, cell cycle arrest, and DNA damage repair. p53 also plays an important role in anti-tumor immunity by regulating TRAIL, DR5, TLRs, Fas, PKR, ULBP1/2, and CCL2; T-cell inhibitory ligand PD-L1; pro-inflammatory cytokines; immune cell activation state; and antigen presentation. Genetic alteration of p53 can contribute to immune evasion by influencing immune cell recruitment to the tumor, cytokine secretion in the TME, and inflammatory signaling pathways. In some contexts, p53 mutations increase neoantigen load which improves response to immune checkpoint inhibition. Therapeutic restoration of mutated p53 can restore anti-cancer immune cell infiltration and ameliorate pro-tumor signaling to induce tumor regression. Indeed, there is clinical evidence to suggest that restoring p53 can induce an anti-cancer immune response in immunologically cold tumors. Clinical trials investigating the combination of p53-restoring compounds or p53-based vaccines with immunotherapy have demonstrated anti-tumor immune activation and tumor regression with heterogeneity across cancer type. In this Review, we discuss the impact of wild-type and mutant p53 on the anti-tumor immune response, outline clinical progress as far as activating p53 to induce an immune response across a variety of cancer types, and highlight open questions limiting effective clinical translation.

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.

Prognostic Ability of Enhancer RNAs in Metastasis of Non-Small Cell Lung Cancer

(1) Background: Non-small cell lung cancer (NSCLC) is the most common lung cancer. Enhancer RNA (eRNA) has potential utility in the diagnosis, prognosis and treatment of cancer, but the role of eRNAs in NSCLC metastasis is not clear; (2) Methods: Differentially expressed transcription factors (DETFs), enhancer RNAs (DEEs), and target genes (DETGs) between primary NSCLC and metastatic NSCLC were identified. Prognostic DEEs (PDEEs) were screened by Cox regression analyses and a predicting model for metastatic NSCLC was constructed. We identified DEE interactions with DETFs, DETGs, reverse phase protein arrays (RPPA) protein chips, immunocytes, and pathways to construct a regulation network using Pearson correlation. Finally, the mechanisms and clinical significance were explained using multi-dimensional validation unambiguously; (3) Results: A total of 255 DEEs were identified, and 24 PDEEs were selected into the multivariate Cox regression model (AUC = 0.699). Additionally, the NSCLC metastasis-specific regulation network was constructed, and six key PDEEs were defined (ANXA8L1, CASTOR2, CYP4B1, GTF2H2C, PSMF1 and TNS4); (4) Conclusions: This study focused on the exploration of the prognostic value of eRNAs in the metastasis of NSCLC. Finally, six eRNAs were identified as potential markers for the prediction of metastasis of NSCLC.

Immunotherapy for Colorectal Cancer: Mechanisms and Predictive Biomarkers

Simple Summary

Late-stage colorectal cancer treatment often involves chemotherapy and radiation that can cause dose-limiting toxicity, and therefore there is great interest in developing targeted therapies for this disease. Immunotherapy is a targeted therapy that uses peptides, cells, antibodies, viruses, or small molecules to engage or train the immune system to kill cancer. Here, we discuss the preclinical and clinical development of immunotherapy for treatment of colorectal cancer and provide an overview of predictive biomarkers for such treatments. We also consider open questions including optimal combination treatments and sensitization of colorectal cancer patients with proficient mismatch repair enzymes.

Abstract

Though early-stage colorectal cancer has a high 5 year survival rate of 65–92% depending on the specific stage, this probability drops to 13% after the cancer metastasizes. Frontline treatments for colorectal cancer such as chemotherapy and radiation often produce dose-limiting toxicities in patients and acquired resistance in cancer cells. Additional targeted treatments are needed to improve patient outcomes and quality of life. Immunotherapy involves treatment with peptides, cells, antibodies, viruses, or small molecules to engage or train the immune system to kill cancer cells. Preclinical and clinical investigations of immunotherapy for treatment of colorectal cancer including immune checkpoint blockade, adoptive cell therapy, monoclonal antibodies, oncolytic viruses, anti-cancer vaccines, and immune system modulators have been promising, but demonstrate limitations for patients with proficient mismatch repair enzymes. In this review, we discuss preclinical and clinical studies investigating immunotherapy for treatment of colorectal cancer and predictive biomarkers for response to these treatments. We also consider open questions including optimal combination treatments to maximize efficacy, minimize toxicity, and prevent acquired resistance and approaches to sensitize mismatch repair-proficient patients to immunotherapy.

Chemotherapy-induced cytokines and prognostic gene signatures vary across breast and colorectal cancer

The mechanisms by which chemotherapeutic drugs mediate efficacy and toxicity in patients across cancers are not fully understood. A poorly understood aspect of the tumor cell response to chemotherapy is cytokine regulation. Some drug-induced cytokines promote the anti-cancer activity of the drugs, but others may promote proliferation, metastasis, and drug resistance. We evaluated effects of clinical chemotherapeutics oxaliplatin, cisplatin, 5-fluorouracil (5-FU), doxorubicin, paclitaxel, docetaxel, and carboplatin on a panel of 52 cytokines in MCF7 breast cancer (BC) cells. We observed pan-drug effects, such as the upregulation of TRAIL-R2 and Chitinase 3-like 1 and drug-specific effects on interleukin and CXCL cytokines. We compared cytokine regulation in MCF7 BC and HCT116 colorectal cancer (CRC) cells, revealing tissue-specific drug effects such as enhanced upregulation of TRAIL-R2 and downregulation of IFN-β and TRAIL in MCF7 by cisplatin, oxaliplatin, and 5-FU. We found that chemotherapy-inducible transcripts have varying potential for prognostic significance in CRC versus BC. Among the non-prognostic CRC genes that were prognostic in BC were NFKBIA and GADD45A, both of which support anti-cancer drug mechanisms. Thus, we establish a novel 7-drug, 52-cytokine signature in MCF7 BC cells and a 3-drug, 40-cytokine signature in HCT116 CRC cells that suggest drug-specific and tissue-specific cytokine regulation. Distinct differences across prognostic gene signatures in BC and CRC further support tissue specificity in the relative impact of drug-regulated genes on patient survival.

Differential p53-Mediated Cellular Responses to DNA-Damaging Therapeutic Agents

The gene TP53, which encodes the tumor suppressor protein p53, is mutated in about 50% of cancers. In response to cell stressors like DNA damage and after treatment with DNA-damaging therapeutic agents, p53 acts as a transcription factor to activate subsets of target genes which carry out cell fates such as apoptosis, cell cycle arrest, and DNA repair. Target gene selection by p53 is controlled by a complex regulatory network whose response varies across contexts including treatment type, cell type, and tissue type. The molecular basis of target selection across these contexts is not well understood. Knowledge gained from examining p53 regulatory network profiles across different DNA-damaging agents in different cell types and tissue types may inform logical ways to optimally manipulate the network to encourage p53-mediated tumor suppression and anti-tumor immunity in cancer patients. This may be achieved with combination therapies or with p53-reactivating targeted therapies. Here, we review the basics of the p53 regulatory network in the context of differential responses to DNA-damaging agents; discuss recent efforts to characterize differential p53 responses across treatment types, cell types, and tissue types; and examine the relevance of evaluating these responses in the tumor microenvironment. Finally, we address open questions including the potential relevance of alternative p53 transcriptional functions, p53 transcription-independent functions, and p53-independent functions in the response to DNA-damaging therapeutics.