Neoadjuvant intratumoral influenza vaccine treatment in patients with proficient mismatch repair colorectal cancer leads to increased tumor infiltration of CD8+ T cells and upregulation of PD-L1: a phase 1/2 clinical trial

Precision oncolytic viral therapy in colorectal cancer: Genetic targeting and immune modulation for personalized treatment (Review)

Colorectal cancer (CRC) is a leading health issue and treatments to eradicate it, such as conventional chemotherapy, are non‑selective and come with a number of complications. The present review focuses on the relatively new area of precision oncolytic viral therapy (OVT), with genetic targeting and immune modifications that offer a new future for CRC treatment. In the present review, an overview of the selection factors that are considered optimal for an oncolytic virus, mechanisms of oncolysis and immunomodulation applied to the OVT, as well as new strategies to improve the efficacy of this method are described. Additionally, cause‑and‑effect relationships are examined for OVT efficacy, mediated by the tumor microenvironment, and directions for genetic manipulation of viral specificity are explored. The possibility of synergy between OVT and immune checkpoint inhibitors and other treatment approaches are demonstrated. Incorporating the details of the present review, biomarker‑guided combination therapies in precision OVT for individualized CRC care, significant issues and future trends in this required area of medicine are highlighted. Increasingly, OVT is leaving the experimental stage and may become routine practice; it provides a new perspective on overcoming CRC and highlights the importance of further research and clinical work.

Neoadjuvant intratumoral MBT(A) immunotherapy prevents distant metastases and recurrence in murine models

Neoadjuvant immunotherapy represents a pioneering approach in the preoperative treatment of cancer, providing new strategies for tumor reduction and improved patient outcomes by modulating the immune response. This study investigated neoadjuvant immunotherapy using intratumoral administration of mannan-BAM, Toll-like receptor ligands, and anti-CD40 antibody (MBTA therapy) followed by surgery in murine models of MTT pheochromocytoma, B16-F10 melanoma, and 4T1 and E0771.lmb mammary carcinomas. In the MTT pheochromocytoma model, it was found that neoadjuvant MBTA therapy followed by surgery could prevent the development of distant metastases in 100% of treated animals, compared to a 60% mortality rate in the control group due to metastatic disease after surgery. These outcomes were achieved even in tumors three times larger than those in the control group. In the aggressive 4T1 model, neoadjuvant MBTA therapy resulted in slower tumor progression and a significant prolongation of survival. In the B16-F10 and E0771.lmb models, neoadjuvant MBTA therapy also protected animals from metastases development and tumor recurrence upon rechallenge with tumor cells after surgery. Transcriptomic analysis revealed enhanced effector immune cell infiltration, cytotoxicity, and antigen presentation in retransplanted tumors from MBTA-treated mice, indicating robust immune memory. Notably, the exclusion of the anti-CD40 antibody from the neoadjuvant MBTA therapy (MBT therapy) yielded comparable outcomes in protection against metastases development. These findings advocate for further investigation of intratumoral neoadjuvant MBTA therapy for immunologically "cold" tumors, including those at high risk of metastases or recurrence.

ER+ HER2- Invasive Breast Cancer: Tumor Remission following Viscum Album Extract/Influenza Vaccine Treatment - A Report of 2 Cases

INTRODUCTION

Many patients with breast cancer use complementary and alternative medicine (CAM) including mistletoe preparations (Viscum album extracts, VAE). CAM alone has been associated with poor outcomes. Few, if any, confirmed breast cancer remissions have been reported with CAM treatment alone.

CASE PRESENTATIONS

Case 1: 60-year-old female with a histologically confirmed local recurrence of hormone receptor positive (HR+) Her2/neu negative (HER2-) breast cancer 3 years after the initial diagnosis and treatment. The patient declined conventional therapies and was treated with intratumoral VAE plus intratumoral influenza vaccine (IV) and concurrent VAE-induced hyperthermia. Lumpectomy 5 months later confirmed a near pathological complete remission (near pCR). Follow-up at 3 years confirms durable remission. Case 2: 57-year-old female with histologically confirmed HR+, HER2- right sided breast cancer with 2-[18F]FDG-PET/computed tomography (CT) positive metastatic disease who declined conventional treatment. The patient was treated with 17 monthly cycles of VAE-induced hyperthermia, eight of which included intratumoral VAE, four of these eight including intratumoral IV. Almost 2 years after treatment start, a follow-up 2-[18F]FDG-PET/CT showed marked morphological and metabolic reduction of breast tumor on the right side, stable local lymph node metastases in the right axilla, complete remission of pulmonary metastases, the single bone metastasis, and the majority of hilomediastinal lymph node metastases but a new metabolic highly active left adrenal lesion.

CONCLUSIONS

Clinical studies of intratumoral VAE-influenza vaccine with concurrent VAE-induced hyperthermia in ER positive HER2/neu negative breast cancer are warranted.

Number of intraepithelial lymphocytes and presence of a subepithelial band in normal colonic mucosa differs according to stainings and evaluation method

Chronic watery diarrhea is a frequent symptom. In approximately 10% of the patients, a diagnosis of microscopic colitis (MC) is established. The diagnosis relies on specific, but sometimes subtle, histopathological findings. As the histology of normal intestinal mucosa vary, discriminating subtle features of MC from normal tissue can be challenging and therefore auxiliary stainings are increasingly used. The aim of this study was to determine the variance in number of intraepithelial lymphocytes (IELs) and presence of a subepithelial band in normal ileum and colonic mucosa, according to different stains and digital assessment. Sixty-one patients without diarrhea referred to screening colonoscopy due to a positive feacal blood test and presenting with endoscopically normal mucosa were included. Basic histological features, number of IELs, and thickness of a subepithelial band was manually evaluated and a deep learning-based algorithm was developed to digitally determine the number of IELs in each of the two compartments; surface epithelium and cryptal epithelium, and the density of lymphocytes in the lamina propria compartment. The number of IELs was significantly higher on CD3-stained slides compared with slides stained with Hematoxylin-and-Eosin (HE) (p<0.001), and even higher numbers were reached using digital analysis. No significant difference between right and left colon in IELs or density of CD3-positive lymphocytes in lamina propria was found. No subepithelial band was present in HE-stained slides while a thin band was visualized on special stains. Conclusively, in this cohort of prospectively collected ileum and colonic biopsies from asymptomatic patients, the range of IELs and detection of a subepithelial collagenous band varied depending on the stain and method used for assessment. As assessment of biopsies from patients with diarrhea constitute a considerable workload in the pathology departments digital image analysis is highly desired. Knowledge provided by the present study highlight important differences that should be considered before introducing this method in the clinic.

Signaling pathways involved in colorectal cancer: pathogenesis and targeted therapy

Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide. Its complexity is influenced by various signal transduction networks that govern cellular proliferation, survival, differentiation, and apoptosis. The pathogenesis of CRC is a testament to the dysregulation of these signaling cascades, which culminates in the malignant transformation of colonic epithelium. This review aims to dissect the foundational signaling mechanisms implicated in CRC, to elucidate the generalized principles underpinning neoplastic evolution and progression. We discuss the molecular hallmarks of CRC, including the genomic, epigenomic and microbial features of CRC to highlight the role of signal transduction in the orchestration of the tumorigenic process. Concurrently, we review the advent of targeted and immune therapies in CRC, assessing their impact on the current clinical landscape. The development of these therapies has been informed by a deepening understanding of oncogenic signaling, leading to the identification of key nodes within these networks that can be exploited pharmacologically. Furthermore, we explore the potential of integrating AI to enhance the precision of therapeutic targeting and patient stratification, emphasizing their role in personalized medicine. In summary, our review captures the dynamic interplay between aberrant signaling in CRC pathogenesis and the concerted efforts to counteract these changes through targeted therapeutic strategies, ultimately aiming to pave the way for improved prognosis and personalized treatment modalities in colorectal cancer.

Neoadjuvant immunotherapy based on PD-1/L1 inhibitors for gastrointestinal tumors: a review of the rationale and clinical advances

The landscape of current tumor treatment has been revolutionized by the advent of immunotherapy based on PD-1/PD-L1 inhibitors. Leveraging its capacity to mobilize systemic antitumor immunity, which is primarily mediated by T cells, there is growing exploration and expansion of its potential value in various stages of clinical tumor treatment. Neoadjuvant immunotherapy induces a robust immune response against tumors prior to surgery, effectively facilitating tumor volume reduction, early eradication or suppression of tumor cell activity, and control of potential metastatic spread, to improve curative surgical resection rates, and prevent tumor recurrence. This review delineates the theoretical basis of neoadjuvant immunotherapy from preclinical research evidence, discusses specific challenges in clinical application, and provides a comprehensive overview of clinical research progress in neoadjuvant immunotherapy for gastrointestinal tumors. These findings suggest that neoadjuvant immunotherapy has the potential to ameliorate immunosuppressive states and enhance cytotoxic T cell function while preserving lymphatic drainage in the preoperative period. However, further investigations are needed on specific treatment regimens, suitable patient populations, and measurable endpoints. Despite numerous studies demonstrating the promising efficacy and manageable adverse events of neoadjuvant immunotherapy in gastrointestinal tumors, the availability of high-quality randomized controlled trials is limited, which highlights the necessity for further research.

The future of cancer vaccines against colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is the second most lethal malignancy worldwide. Immune checkpoint inhibitors (ICIs) benefit only 15% of patients with mismatch repair-deficient/microsatellite instability (dMMR/MSI) CRC. The majority of patients are not suitable due to insufficient immune infiltration. Cancer vaccines are a potential approach for inducing tumor-specific immunity within the solid tumor microenvironment.

AREA COVERED

In this review, we have provided an overview of the current progress in CRC vaccines over the past three years and briefly depict promising directions for further exploration.

EXPERT OPINION

Cancer vaccines are certainly a promising field for the antitumor treatment against CRC. Compared to monotherapy, cancer vaccines are more appropriate as adjuvants to standard treatment, especially in combination with ICI blockade, for microsatellite stable patients. Improved vaccine construction requires neoantigens with sufficient immunogenicity, satisfactory HLA-binding affinity, and an ideal delivery platform with perfect lymph node retention and minimal off-target effects. Prophylactic vaccines that potentially prevent CRC carcinogenesis are also worth investigating. The exploration of appropriate biomarkers for cancer vaccines may benefit prognostic prediction analysis and therapeutic response prediction in patients with CRC. Although many challenges remain, CRC vaccines represent an exciting area of research that may become an effective addition to current guidelines.

Redefining the battle against colorectal cancer: a comprehensive review of emerging immunotherapies and their clinical efficacy

Colorectal cancer (CRC) is the third most common cancer globally and presents a significant challenge owing to its high mortality rate and the limitations of traditional treatment options such as surgery, radiotherapy, and chemotherapy. While these treatments are foundational, they are often poorly effective owing to tumor resistance. Immunotherapy is a groundbreaking alternative that has recently emerged and offers new hope for success by exploiting the body's own immune system. This article aims to provide an extensive review of clinical trials evaluating the efficacy of various immunotherapies, including CRC vaccines, chimeric antigen receptor T-cell therapies, and immune checkpoint inhibitors. We also discuss combining CRC vaccines with monoclonal antibodies, delve into preclinical studies of novel cancer vaccines, and assess the impact of these treatment methods on patient outcomes. This review seeks to provide a deeper understanding of the current state of CRC treatment by evaluating innovative treatments and their potential to redefine the prognosis of patients with CRC.

Intratumoral Influenza Vaccine Administration Attenuates Breast Cancer Growth and Restructures the Tumor Microenvironment through Sialic Acid Binding of Vaccine Hemagglutinin

Breast cancer continues to have a high disease burden worldwide and presents an urgent need for novel therapeutic strategies to improve outcomes. The influenza vaccine offers a unique approach to enhance the anti-tumor immune response in patients with breast cancer. Our study explores the intratumoral use of the influenza vaccine in a triple-negative 4T1 mouse model of breast cancer. We show that the influenza vaccine attenuated tumor growth using a three-dose intratumoral regimen. More importantly, prior vaccination did not alter this improved anti-tumor response. Furthermore, we characterized the effect that the influenza vaccine has on the tumor microenvironment and the underlying mechanisms of action. We established that the vaccine facilitated favorable shifts in restructuring the tumor microenvironment. Additionally, we show that the vaccine's ability to bind sialic acid residues, which have been implicated in having oncogenic functions, emerged as a key mechanism of action. Influenza hemagglutinin demonstrated binding ability to breast cancer cells through sialic acid expression. When administered intratumorally, the influenza vaccine offers a promising therapeutic strategy for breast cancer patients by reshaping the tumor microenvironment and modestly suppressing tumor growth. Its interaction with sialic acids has implications for effective therapeutic application and future research.