Doxorubicin (DOX) is a potent anti-cancer agent that has garnered great interest in research due to its high efficacy despite dose-limiting toxicities. Several strategies have been exploited to enhance the efficacy and safety profile of DOX. Liposomes are the most established approach. Despite the improvement in safety properties of liposomal encapsulated DOX (in Doxil and Myocet), the efficacy is not superior to conventional DOX. Functionalized (targeted) liposomes present a more effective system to deliver DOX to the tumor. Moreover, encapsulation of DOX in pH-sensitive liposomes (PSLs) or thermo-sensitive liposomes (TSLs) combined with local heating has improved DOX accumulation in the tumor. Lyso-thermosensitive liposomal DOX (LTLD), MM-302, and C225-immunoliposomal(IL)-DOX have reached clinical trials. Further functionalized PEGylated liposomal DOX (PLD), TSLs, and PSLs have been developed and evaluated in preclinical models. Most of these formulations improved the anti-tumor activity compared to the currently available liposomal DOX. However, the fast clearance, the optimization of ligand density, stability, and release rate need more investigations. Therefore, we reviewed the latest approaches applied to deliver DOX more efficiently to the tumor, preserving the benefits obtained from FDA-approved liposomes.

Immune checkpoint inhibitors (ICIs) have changed how we think about tumor management. Combinations of anti-programmed death ligand-1 (PD-L1) immunotherapy have become the standard of care in many advanced-stage cancers, including as a first-line therapy. Aside from improved anti-tumor immunity, the mechanism of action of immune checkpoint inhibitors (ICIs) exposes a new toxicity profile known as immune-related adverse effects (irAEs). This novel toxicity can damage any organ, but the skin, digestive and endocrine systems are the most frequently afflicted. Most ICI-attributed toxicity symptoms are mild, but some are severe and necessitate multidisciplinary side effect management. Obtaining knowledge on the various forms of immune-related toxicities and swiftly changing treatment techniques to lower the probability of experiencing severe irAEs has become a priority in oncological care. In recent years, there has been a growing understanding of an intriguing link between the gut microbiome and ICI outcomes. Multiple studies have demonstrated a connection between microbial metagenomic and metatranscriptomic patterns and ICI efficacy in malignant melanoma, lung and colorectal cancer. The immunomodulatory effect of the gut microbiome can have a real effect on the biological background of irAEs as well. Furthermore, specific microbial signatures and metabolites might be associated with the onset and severity of toxicity symptoms. By identifying these biological factors, novel biomarkers can be used in clinical practice to predict and manage potential irAEs. This comprehensive review aims to summarize the clinical aspects and biological background of ICI-related irAEs and their potential association with the gut microbiome and metabolome. We aim to explore the current state of knowledge on the most important and reliable irAE-related biomarkers of microbial origin and discuss the intriguing connection between ICI efficacy and toxicity.

Triple‐negative breast cancer (TNBC) is a leading cause of cancer mortality and lacks modern therapy options. Modulated electro‐hyperthermia (mEHT) is an adjuvant therapy with demonstrated clinical efficacy for the treatment of various cancer types. In this study, we report that mEHT monotherapy stimulated interleukin‐1 beta (IL‐1β) and interleukin‐6 (IL‐6) expression, and consequently cyclooxygenase 2 (COX‐2), which may favor a cancer‐promoting tumor microenvironment. Thus, we combined mEHT with nonsteroid anti‐inflammatory drugs (NSAIDs): a nonselective aspirin, or the selective COX‐2 inhibitor SC236, in vivo. We demonstrate that NSAIDs synergistically increased the effect of mEHT in the 4T1 TNBC model. Moreover, the strongest tumor destruction ratio was observed in the combination SC236 + mEHT groups. Tumor damage was accompanied by a significant increase in cleaved caspase‐3, suggesting that apoptosis played an important role. IL‐1β and COX‐2 expression were significantly reduced by the combination therapies. In addition, a custom‐made nanostring panel demonstrated significant upregulation of genes participating in the formation of the extracellular matrix. Similarly, in the B16F10 melanoma model, mEHT and aspirin synergistically reduced the number of melanoma nodules in the lungs. In conclusion, mEHT combined with a selective COX‐2 inhibitor may offer a new therapeutic option in TNBC.

Modulated electro-hyperthermia (mEHT) is an adjuvant cancer therapy that enables tumor-selective heating (+2.5 °C). In this study, we investigated whether mEHT accelerates the tumor-specific delivery of doxorubicin (DOX) from lyso-thermosensitive liposomal doxorubicin (LTLD) and improves its anticancer efficacy in mice bearing a triple-negative breast cancer cell line (4T1). The 4T1 cells were orthotopically injected into Balb/C mice, and mEHT was performed on days 9, 12, and 15 after the implantation. DOX, LTLD, or PEGylated liposomal DOX (PLD) were administered for comparison. The tumor size and DOX accumulation in the tumor were measured. The cleaved caspase-3 (cC3) and cell proliferation were evaluated by cC3 or Ki67 immunohistochemistry and Western blot. The LTLD+mEHT combination was more effective at inhibiting tumor growth than the free DOX and PLD, demonstrated by reductions in both the tumor volume and tumor weight. LTLD+mEHT resulted in the highest DOX accumulation in the tumor one hour after treatment. Tumor cell damage was associated with cC3 in the damaged area, and with a reduction in Ki67 in the living area. These changes were significantly the strongest in the LTLD+mEHT-treated tumors. The body weight loss was similar in all mice treated with any DOX formulation, suggesting no difference in toxicity. In conclusion, LTLD combined with mEHT represents a novel approach for DOX delivery into cancer tissue.

Triple-negative breast cancer (TNBC) is a highly aggressive breast cancer type with no targeted therapy and hence limited treatment options. Modulated electrohyperthermia (mEHT) is a novel complementary therapy where a 13.56 MHz radiofrequency current targets cancer cells selectively, inducing tumor damage by thermal and electromagnetic effects. We observed severe vascular damage in mEHT-treated tumors and investigated the potential synergism between mEHT and inhibition of tumor vasculature recovery in our TNBC mouse model. 4T1/4T07 isografts were orthotopically inoculated and treated three to five times with mEHT. mEHT induced vascular damage 4–12 h after treatment, leading to tissue hypoxia detected at 24 h. Hypoxia in treated tumors induced an angiogenic recovery 24 h after the last treatment. Administration of the cardiac glycoside digoxin with the potential hypoxia-inducible factor 1-α (HIF1-α) and angiogenesis inhibitory effects could synergistically augment mEHT-mediated tumor damage and reduce tissue hypoxia signaling and consequent vascular recovery in mEHT-treated TNBC tumors. Conclusively, repeated mEHT induced vascular damage and hypoxic stress in TNBC that promoted vascular recovery. Inhibiting this hypoxic stress signaling enhanced the effectiveness of mEHT and may potentially enhance other forms of cancer treatment.

Background Metastasis is the main cause of death in breast cancer patients. Lymph node metastasis is associated with poor overall survival and is often associated with recurrences. The molecular mechanisms controlling tumor metastasis are complex and there is an emerging evidence supporting the direct involvement of the chemokines and their receptors in this process. To the interest of this study, previous data from the literature show that the CCL21 and CCL19 and their receptor CCR7 are expressed in breast cancer and may be associated with lymph node metastasis. The aim of this study is to assess the expression of CCL19/CCL21 and their receptor CCR7 in breast cancer tissues and both negative and positive regional lymph nodes using RT-PCR technology. Material and Methods Formalin fixed paraffin embedded breast cancer specimens obtained from mastectomy were included in the study. RNA isolation using Acidic Phenol method was performed, and then RT-PCR was conducted on both primary tumor and corresponding lymph nodes using specific primers for the studied CCL21/CCL19 chemokines, CCR7 receptor and the positive control GAPDH. Results The results of this study have revealed a significant positive correlation in mRNA expression in the tumor samples between CCL21 vs. CCL19 (R²=0.9, P-value= 0.02), as well as between CCR7 vs CCL21, and CCR7vs. CCL19 (R²=0.87, P value= 0.04) (R²=0.98, P value= 0.002) respectively. Moreover, there was a significant positive correlation (R²=0.9, P value= 0.02) in CCL19 expression in primary and secondary tumor. Furthermore, the expression of CCL21 chemokine in negative lymph nodes was more than the expression of it in positive lymph nodes with significant importance (P value = 0.01). The Study of the correlation between CCL21/CCL19 expression in breast tumors and the clinical and pathological parameters, has illustrated a significant correlation between CCL21 vs. CCL19 mRNA expression in breast tumors and triple negative of PR, ER, Her-2 receptors. Conclusion The results of the study have revealed a potential role of CCR7-CCL21/CCL19 axis in breast cancer. Moreover the results suggest an important role of CCL19 in Lymph nodes metastasis compared to CCL21. Furthermore, the study has showed that CCL21/CCL19 chemokines are expressed in breast tumors with poor prognosis.