Local Destruction of Tumors and Systemic Immune Effects

The Efficacy of Electrochemotherapy with Dacarbazine on Melanoma Cells

Electrochemotherapy (ECT) involves locally applying electrical pulses to permeabilize cell membranes, using electroporation (EP). This process enhances the uptake of low-permeant chemotherapeutic agents, consequently amplifying their cytotoxic effects. In melanoma treatment, dacarbazine (DTIC) is a cornerstone, but it faces limitations because of poor cell membrane penetration, necessitating the use of high doses, which, in turn, leads to increased side effects. In our study, we investigated the effects of DTIC and EP, both individually and in combination, on the melanoma cell line (SK-MEL-30) as well as human dermal fibroblasts (HDF) using in vitro assays. First, the effects of different DTIC concentrations on the viability of SK-MEL-30 and HDF cells were determined, revealing that DTIC was more effective against melanoma cells at lower concentrations, whereas its cytotoxicity at 1000 μM was similar in both cell types. Next, an ideal electric field strength of 1500 V/cm achieved a balance between permeability (84%) and melanoma cell viability (79%), paving the way for effective ECT. The combined DTIC-EP (ECT) application reduced IC50 values by 2.2-fold in SK-MEL-30 cells and 2.7-fold in HDF cells compared with DTIC alone. In conclusion, ECT not only increased DTIC's cytotoxicity against melanoma cells but also affected healthy fibroblasts. These findings emphasize the need for cautious, targeted ECT management in melanoma therapy.

Threatment Strategies for Recurrent Hepatocellular Carcinoma Patients: Ablation and its Combination Patterns

With the development of guidance technology and ablation equipment, ablative procedures have emerged as important loco-regional alternatives to surgical resection for recurrent hepatocellular carcinoma (rHCC) patients. Currently, ablation modalities used in clinical practice mainly include radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation (LA), cryoablation (CRA), high-intensity focused ultrasound (HIFU), and irreversible electroporation (IRE). Accumulated comparative data of ablation versus surgical resection reveal noninferior responses and outcomes but superior adverse effects. Moreover, studies demonstrate that ablation may serve as an excellent procedure for rHCC given its exact minimal invasiveness and immune modulation. We focus on the current status of ablation in clinical practice for rHCC and discuss new research in the field, including ablation combined with these other modalities, such as targeted therapy and immunotherapy.

Inducing the Abscopal Effect in Liver Cancer Treatment: The Impact of Microwave Ablation Power Levels and PD-1 Antibody Therapy

Microwave ablation (MWA) is an effective treatment for liver cancer (LC), but its impact on distant tumors remains to be fully elucidated. This study investigated the abscopal effects triggered by MWA treatment of LC, at different power levels and with or without combined immune checkpoint inhibition (ICI). We established a mouse model with bilateral subcutaneous LC and applied MWA of varied power levels to ablate the right-sided tumor, with or without immunotherapy. Left-sided tumor growth was monitored to assess the abscopal effect. Immune cell infiltration and distant tumor neovascularization were quantified via immunohistochemistry, revealing insights into the tumor microenvironment and neovascularization status. Th1- and Th2-type cytokine concentrations in peripheral blood were measured using ELISA to evaluate systemic immunological changes. It was found that MWA alone, especially at lower power, promoted distant tumor growth. On the contrary, combining high-power MWA with anti-programmed death (PD)-1 therapy promoted CD8+ T-cell infiltration, reduced regulatory T-cell infiltration, upregulated a Th1-type cytokine (TNF-α) in peripheral blood, and inhibited distant tumor growth. In summary, combining high-power MWA with ICI significantly enhances systemic antitumor immune responses and activates the abscopal effect, offering a facile and robust strategy for improving treatment outcomes.

The Pre-Ablation Circulating Tumor-Associated Inflammatory Index Predicts the Prognosis of Patients with Liver Metastasis from Pancreatic Cancer

OBJECTIVE

Ablation serves as a common local treatment for liver metastases from pancreatic cancer (PCLM), but the correlation between the prognosis of PCLM and inflammatory cytokines has been rarely reported. This study aimed to establish a cytokine-based prognostic model for patients with PCLM who are receiving ablation.

PATIENTS AND METHODS

Serum samples from peripheral blood were collected from patients with PCLM before their first ablation. Cytokines were measured using Luminex chips and ELISA. Cox regression and least absolute shrinkage and selection operator regression were used to select prognostic factors for overall survival (OS). Area under the receiver operating characteristic curve (AUC) was applied to compare the ability to predict survival.

RESULTS

The relationship between cytokines and clinical factors was evaluated and their prognostic value was compared. Six optimal predictors were selected, including IL-2, IL-7, HGF, IFN-γ, CA19-9 and CEA. The risk model based on these predictors was built and named circulating tumor-associated inflammatory index (CTII). The CTII (AUCs > 0.90) showed superior performance to systemic immune-inflammation index (SII, AUCs < 0.65) in OS.

CONCLUSION

A circulating cytokine-based risk model for patients with PCLM before first ablation has been proposed and validated, which has demonstrated superior performance in predicting survival and has the potential to inform clinical treatment strategies.

Pretreatment Immune Status, Predicts Response to Definite Chemo Radiotherapy in Advanced Stages of Cervical Cancer Patients

Objective

To evaluate the prognostic role of pretreatment CD4 + , CD8 + T lymphocytes in predicting response to definite chemo radiotherapy in advanced cervical cancer. Design: A hospital-based prospective one-year follow-up study.

Method

This observational study was conducted on 74 patients with advanced cervical cancer. Pretreatment CD4 + and CD8 + levels in cervical cancer tissue and peripheral blood was noted and quantitatively assessed in patients with complete remission or persistent disease after one year of follow-up.

Results

There was a statistically significant association of tumour volume with the remission or persistence of disease. In peripheral blood, mean CD4 + score and CD4 + /CD8 + ratio were significantly higher while mean CD8 + score is significantly lower in patients with remission. Similar results were seen in tumour tissue as well. On Receiver Operating Curve analysis, the cut-off value of CD4 + , CD8 + and CD4 + /CD8 + ratio in predicting remission or persistent disease in peripheral blood was 20.09, 18.51 and 0.41 while in tumor tissue was 19.71, 20.99 and 0.20, respectively.

Conclusion

The patients with tumor volume < 100 cm 2 have much higher chances of remission. The patients with higher CD4 + and CD4 + / CD8 + ratio, both in peripheral blood as well as tumor tissue, have higher chances of remission. The cut-off value of CD4 + , CD8 + and CD4 + /CD8 + ratio in predicting remission or persistent disease in peripheral blood was 20.09, 18.51 and 0.41 while in tumor tissue was 19.71, 20.99 and 0.20, respectively.

Local Destruction of Tumors for Systemic Immunoresponse: Engineering Antigen-Capturing Nanoparticles as Stimulus-Responsive Immunoadjuvants

Immunotherapy has established a new paradigm for cancer treatment and made many breakthroughs in clinical practice. However, the rarity of immune response suggests that additional intervention is necessary. In recent years, it has been reported that local tumor destruction (LTD) can cause cancer cell death and induce an immunologic response. Thus, the combination of immunotherapy and LTD methods will be a promising approach to improve immune efficiency for cancer treatment. Herein, a nanobiotechnology platform to achieve high-precision LTD for systemic cancer immunotherapy has been successfully constructed. Possessing radio-sensitizing and photothermal properties, the engineered immunoadjuvant-loaded nanoplatform, which could precisely induce radiotherapy (RT)/photothermal therapy (PTT) to eliminate local tumor and meanwhile lead to the release of tumor-derived protein antigens (TDPAs), has been facilely fabricated by commercialized SPG membrane emulsification technology. Further on, the TDPAs could be captured and form personal nanovaccines in situ to serve as both reservoirs of antigen and carriers of immunoadjuvant, which can effectively improve the immune response. The investigations suggest that the combination of RT/PTT and improved immunotherapy using adjuvant-encapsulated antigen-capturing nanoparticles holds tremendous promise in cancer treatments.

Tumor-Infiltrating Lymphocytes (TILs) as a Biomarker of Abscopal Effect of Cryoablation in Breast Cancer: A Pilot Study

Background

Morphological evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer is gaining momentum as an immunological biomarker. This experiment evaluates the role of TILs in distant tumors as a measure of abscopal effect from cryoablation of breast cancer.

Methods

BALB/c mice underwent bilateral orthotopic transplant with 4T1-12B (triple-negative) cells. At 2 weeks, left tumors were treated by either resection (standard of care group) or cryoablation (intervention group) followed by resection of the distant right tumors 1 week posttreatment. TIL scores were calculated from hematoxylin and eosin-stained sections and phenotyped for cytotoxic T-lymphocyte (CTL) markers by immunofluorescence. Primarily resected tumors served as baseline (Tbaseline), whereas resected distant right-sided served as the readout for abscopal effect (AbsRes or AbsCryo). Mice were monitored for tumor recurrence and metastasis.

Results

The AbsCryo had a significant mean (SD) increase in stromal (2.8 [1.1]%; p = 0.015) and invasive margin TILs (50 [12]%; p = 0.02) compared with TBaseline (1.0 [0]% and 31 [4.9]%, respectively). CTL phenotyping revealed a significant increase in mean (SD) CD8+ T cells (15.7 [12.1]; p = 0.02) and granzyme B (4.8 [3.6]; p = 0.048) for the AbsCryo compared with TBaseline (5.2 [4.7] and 2.4 [0.9], respectively). Posttreatment, the cryoablation group had no recurrence or metastasis, whereas the resected group showed local recurrence and lung metastasis in 40% of the mice. Postprocedure increase in TIL score of distant tumors was associated with decrease in tumor relapse (p = 0.02).

Conclusions

Cryoablation induced a robust tumor-specific TIL response compared with resection, suggesting an abscopal effect leading to the prevention of cancer recurrence and metastasis.