T cells and adoptive immunotherapy: recent developments and future prospects in gastrointestinal oncology. Clin Dev Immunol. 2011;2011:320571. [PMID: 22110523 PMCID: PMC3216375 DOI: 10.1155/2011/320571]

Preclinical evaluation of chimeric antigen receptor T cells targeting the carcinoembryonic antigen as a potential immunotherapy for gallbladder cancer

Gallbladder cancer (GBC) is commonly diagnosed at late stages when conventional treatments achieve only modest clinical benefit. Therefore, effective treatments for advanced GBC are needed. In this context, the administration of T cells genetically engineered with chimeric antigen receptors (CAR) has shown remarkable results in hematological cancers and is being extensively studied for solid tumors. Interestingly, GBC tumors express canonical tumor-associated antigens, including the carcinoembryonic antigen (CEA). However, the potential of CEA as a relevant antigen in GBC to be targeted by CAR-T cell-based immunotherapy has not been addressed. Here we show that CEA was expressed in 88% of GBC tumors, with higher levels associated with advanced disease stages. CAR-T cells specifically recognized plate-bound CEA as evidenced by up-regulation of 4-1BB, CD69 and PD-1, and production of effector cytokines IFN-γ and TNF-α. In addition, CD8+ CAR-T cells up-regulated the cytotoxic molecules granzyme B and perforin. Interestingly, CAR-T cell activation occurred even in the presence of PD-L1. Consistent with these results, CAR-T cells efficiently recognized GBC cell lines expressing CEA and PD-L1, but not a CEA-negative cell line. Furthermore, CAR-T cells exhibited in vitro cytotoxicity and reduced in vivo tumor growth of GB-d1 cells. In summary, we demonstrate that CEA represents a relevant antigen for GBC that can be targeted by CAR-T cells at the preclinical level. This study warrants further development of the adoptive transfer of CEA-specific CAR-T cells as a potential immunotherapy for GBC.

The role of immunogenic cell death in gastrointestinal cancer immunotherapy (Review)

Modern cancer immunotherapy techniques are aimed at enhancing the responses of the patients' immune systems to fight against the cancer. The main promising strategies include active vaccination of tumor antigens, passive vaccination with antibodies specific to cancer antigens, adoptive transfer of cancer-specific T cells and manipulation of the patient's immune response by inhibiting immune checkpoints. The application of immunogenic cell death (ICD) inducers has been proven to enhance the immunity of patients undergoing various types of immunotherapy. The dying, stressed or injured cells release or present molecules on the cell surface, which function as either adjuvants or danger signals for detection by the innate immune system. These molecules are now termed 'damage-associated molecular patterns'. The term 'ICD' indicates a type of cell death that triggers an immune response against dead-cell antigens, particularly those derived from cancer cells, and it was initially proposed with regards to the effects of anticancer chemotherapy with conventional cytotoxic drugs. The aim of the present study was to review and discuss the role and mechanisms of ICD as a promising combined immunotherapy for gastrointestinal tumors.

Metabolomics profile in gastrointestinal cancers: Update and future perspectives

Despite recent progress in diagnosis and therapy, gastrointestinal (GI) cancers remain one of the most important causes of death with a poor prognosis due to late diagnosis. Serum tumor markers and detection of occult blood in the stool are the current tests used in the clinic of GI cancers; however, these tests are not useful as diagnostic screening since they have low specificity and low sensitivity. Considering that one of the hallmarks of cancer is dysregulated metabolism and metabolomics is an optimal approach to illustrate the metabolic mechanisms that belong to living systems, is now clear that this -omics could open a new way to study cancer. In the last years, nuclear magnetic resonance (NMR) metabolomics has demonstrated to be an optimal approach for diseases' diagnosis nevertheless a few studies focus on the NMR capability to find new biomarkers for early diagnosis of GI cancers. For these reasons in this review, we will give an update on the status of NMR metabolomic studies for the diagnosis and development of GI cancers using biological fluids.

Immunotherapeutic Strategies for Gastric Carcinoma: A Review of Preclinical and Clinical Recent Development

Gastric carcinoma (GC) is the 2nd most common cause of cancer-related death. Despite advances in conventional treatment and surgical interventions, a high percentage of GC patients still have poor survival. Recently, immunotherapy has become a promising approach to treat GC. Here, we present preclinical and clinical studies encouraging the use of vaccination, adoptive T-cell therapy (ACT), and immune checkpoint inhibitors, such as programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) or cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). The ongoing immunotherapy clinical trials have shown promising results in safety and tolerability even in late-stage GC patients. Moreover, we highlight that the combination of ACT with chemotherapy could be the best choice to treat GC.

Immunotherapy in Gastrointestinal Cancers

Gastrointestinal cancers represent a major public health problem worldwide. Immunotherapeutic strategies are currently under investigation in this setting and preliminary results of ongoing trials adopting checkpoint inhibitors are striking. Indeed, although a poor immunogenicity for GI has been reported, a strong biological rationale supports the development of immunotherapy in this field. The clinical and translational research on immunotherapy for the treatment of GI cancers started firstly with the identification of immune-related mechanisms possibly relevant to GI tumours and secondly with the development of immunotherapy-based agents in clinical trials. In the present review a general overview is firstly provided followed by a focus on major findings on gastric, colorectal, and hepatocellular carcinomas. Finally, pathological and molecular perspectives are provided since many efforts are ongoing in order to identify possible predictive biomarkers and to improve patients' selection. Many issues are still unsolved in this field; however, we strongly believe that immunotherapy might positively affect the natural history of a subgroup of GI cancer patients improving outcome and the overall quality of life.

Prognostic Value of Lymph Node Ratio in Locally Advanced Rectal Cancer Patients After Preoperative Chemoradiotherapy Followed by Total Mesorectal Excision

Although the absolute number of positive lymph nodes (LNs) has been established as 1 of the most important prognostic factors in rectal cancers, many researchers have proposed that the lymph node ratio (LNR) may have better predicted outcomes. We conducted a retrospective study to compare the predictive ability of LNR and ypN category in rectal cancer. A total of 264 locally advanced rectal cancer (LARC) patients who underwent preoperative chemoradiotherapy (CRT) followed by total mesorectal excision (TME) between 2005 and 2012 were reviewed. All patients were categorized into 3 groups or patients with metastatic LNs were categorized into 2 groups according to the LNR. The prognostic effect on overall survival (OS) and disease-free survival (DFS) was evaluated. With a median follow-up of 45 months, the OS and DFS were 68.4% and 59.3% for the entire cohort, respectively. The respective 5-year OS and DFS rates for the 3 groups (LNR = 0, 0 < LNR ≤ 0.20, and 0.20 < LNR ≤ 1.0) were as follows: 83.2%, 72.6%, and 49.4% (P < 0.001) and 79.5%, 57.3%, and 33.5% (P < 0.001), respectively. Multivariate analysis revealed that LNR and differentiation, but not the number of positive LNs, had independent prognostic value for OS (hazard ratio [HR] = 2.328, 95% confidence interval [CI]: 1.850-4.526, P < 0.001) and DFS (HR = 3.004, 95% CI: 1.616-5.980, P < 0.001). As for patients with positive LNs, the respective 5-year OS and DFS rates for the 2 groups (0 < LNR ≤ 0.20, and 0.20 < LNR ≤ 1.0) were 72.6% and 49.4% (P < 0.001) and 57.3% and 33.5% (P < 0.001), respectively. Multivariate analysis revealed that only LNR was an independent factor for OS (HR = 3.214, 95% CI: 1.726-5.986, P < 0.001) and DFS (HR = 4.230, 95% CI: 1.825-6.458, P < 0.001). Subgroups analysis demonstrated that the ypN category had no impact on survival whereas increased LNR was a significantly prognostic indicator for worse survival in the LNs < 12 subgroup. LNR is an independent prognostic factor in LARC patients treated with preoperative CRT followed by TME. It may be a better independent staging method than the number of metastatic LNs when <12 LNs are harvested after preoperative CRT.

Immune response, safety, and survival and quality of life outcomes for advanced colorectal cancer patients treated with dendritic cell vaccine and cytokine-induced killer cell therapy

Purpose. To determine the immune response after dendritic cell (DC) vaccine and cytokine-induced killer cells (CIK) therapy and assess its associated toxicity, survival benefit, and changes in the quality of life (QOL) of advanced colorectal cancer (CRC) patients. Methods. We recruited 100 patients with unresectable CRC orrelapsed CRC after surgery who received DC vaccine and CIK cells (group immunotherapy, group I), and, as a control, 251 patients who had similar characteristics and underwent similar treatments, except for this immunotherapy (group nonimmunotherapy, group NI). After a follow-up period of 489.2 ± 160.4 days, overall survival (OS) of the two groups was compared using the Kaplan-Meier method. Results. In group I, 62% of patients developed a positive delayed type hypersensitivity response, and most patients showed an improvement in physical strength (75.2%), appetite (74.2%), sleeping (72.1%), and body weight (70.1%). Adverse events were fever (29.5%), insomnia (19.2%), anorexia (9.1%), sore joints (5.4%), and skin rash (1.0%). No toxicity was observed in patients treated with DC vaccine and CIK therapy. OS was significantly longer in group I than in group NI (P = 0.043). Conclusion. DC vaccine and CIK therapy were safe and could induce an immune response against CRC, thereby improving QOL and prolonging OS.

Immunotherapy for gastrointestinal malignancies

BACKGROUND

Gastrointestinal (GI) cancers are the most common human tumors encountered worldwide. The majority of GI cancers are unresectable at the time of diagnosis, and in the subset of patients undergoing resection, few are cured. There is only a modest improvement in survival with the addition of modalities such as chemotherapy and radiation therapy. Due to an increasing global cancer burden, it is imperative to integrate alternative strategies to improve outcomes. It is well known that cancers possess diverse strategies to evade immune detection and destruction. This has led to the incorporation of various immunotherapeutic strategies, which enable reprogramming of the immune system to allow effective recognition and killing of GI tumors.

METHODS

A review was conducted of the results of published clinical trials employing immunotherapy for esophageal, gastroesophageal, gastric, hepatocellular, pancreatic, and colorectal cancers.

RESULTS

Monoclonal antibody therapy has come to the forefront in the past decade for the treatment of colorectal cancer. Immunotherapeutic successes in solid cancers such as melanoma and prostate cancer have led to the active investigation of immunotherapy for GI malignancies, with some promising results.

CONCLUSIONS

To date, monoclonal antibody therapy is the only immunotherapy approved by the US Food and Drug Administration for GI cancers. Initial trials validating new immunotherapeutic approaches, including vaccination-based and adoptive cell therapy strategies, for GI malignancies have demonstrated safety and the induction of antitumor immune responses. Therefore, immunotherapy is at the forefront of neoadjuvant as well as adjuvant therapies for the treatment and eradication of GI malignancies.