Current Cancer Drug Targets - Volume 23, Issue 9, 2023

The corresponding mRNA vaccines Comirnaty (BNT162b2) and Spikevax (mRNA-1273) have been authorized for emergency use since the COVID-19 outbreak. Most clinical researches have also discovered that the mRNA vaccine is a revolutionary strategy for preventing and treating numerous diseases, including cancers. Unlike viral vectors or DNA vaccines, mRNA vaccines cause the body to directly produce proteins following injection. Delivery vectors and mRNAs that encode tumor antigens or immunomodulatory molecules work together to trigger an anti-tumor response. Before mRNA vaccines may be employed in clinical trials, a number of challenges need to be resolved. These include establishing effective and safe delivery systems, generating successful mRNA vaccines against diverse types of cancers, and proposing improved combination therapy. Therefore, we need to improve vaccine-specific recognition and develop mRNA delivery mechanisms. This review summarizes the complete mRNA vaccines’ elemental composition and discusses recent research progress and future direction for mRNA tumor vaccines.

Resistance to conventional antitumour therapies and Hypoxia in patients with advanced solid tumours are two major reasons for the failure of conventional anti-tumour therapies. Therefore, it is important to find a new therapeutic method that can overcome these problems. An attenuated anaerobic bacterium, Clostridium novyi-NT, could target Hypoxic and Necrotic areas of tumours causing tumour lysis and stimulating a host anti-tumour immune response. To the best of our knowledge, the combination of bacterial anti-tumour therapy, chemotherapy, radiotherapy and immunotherapy may promote tumour regression, inhibit metastasis and develop a new strategy for the treatment of solid tumours. However, the possible molecular mechanisms of the combined therapies are still the biggest challenge. This review provides an overview of the history of bacterial cancer therapy and the development of a non-lethal strain of Clostridium novyi. Below is a precise definition of Hypoxic conditions in solid tumour tissue. To understand the anticancer effect of Clostridium novyi-NT spores, possible cell death mechanisms were summarised by the enzyme phospholipase C (nt01cx0979), which is secreted by Clostridium novyi-NT spores after germination in tumour tissue. The function of Clostridium novyi-NT spores in stimulating the host immune system to elicit anti-tumour responses was reviewed. Then, the results of anti-tumour combination therapies based on Clostridium novyi-NT spores were compiled. Identifying the molecular mechanisms of Clostridium novyi-NT in treating tumours and inducing cell death in invasive cancer cells, ultimately leading to tumour regression, may develop promising clinical strategies in the combined treatment of solid tumours.

There is a significant unmet demand for the treatment of pancreatic cancer. Many patients do not make it to past five years after diagnosis. The effectiveness of treatment varies greatly from patient to patient, and many people are too weak to endure chemotherapy or surgery. Unfortunately, by the time patients receive the diagnosis, the tumour typically spreads, rendering these chemotherapies ineffective. Effective anticancer drugs can be better formulated with the help of nanotechnology, which can help them overcome issues with their physicochemical features, such as their poor water solubility or their short half-life in the bloodstream after administration. Many of the reported nanotechnologies offer multifunctional qualities including image guidance and controlled release, in addition to site-specific targeting to the site of action. In this review, we will examine the current status of the most promising nanotechnologies for treating pancreatic cancer, including those still in the research and development phase as well as those that have recently been given the green signal for use in clinical practice.

Background: The optimal second-line therapy for hormone receptor-positive (HR+)/ human epidermal growth factor receptor 2 negative (HER2−) advanced or metastatic breast cancer is yet to be established. Therefore, we conducted a network meta-analysis (NMA) of marketed drugs to compare their efficacy. Methods: We searched the literature in PubMed, Embase, Web of Science databases, and the main international conferences in the past 5 years to find phase III clinical trials on drugs available in the market. Network meta-analysis of progression-free survival (PFS), overall survival (OS), and the objective response rate (ORR) was performed using R software. The efficiency of treatment options was compared using hazard ratios and 95% credibility intervals. Results: Overall, 12 studies with 6120 patients were included in the analysis. In an indirect comparison of the five regimens, cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) plus 500 mg fulvestrant (Ful500) gave the best PFS results; palbociclib ranked first with a surface under the cumulative ranking (SUCRA) of 94.99%, followed by mammalian target of rapamycin inhibitor (mTORi) plus everolimus (SUCRA=73.07%), phosphoinositide 3-kinase inhibitor (PI3Ki) plus Ful500 (SUCRA=66.73%), Ful500 alone (SUCRA=44.55%), and histone deacetylase inhibitor (HDACi) plus exemestane (SUCRA= 43.49%). However, no significant difference was found in the PFS rates of CDK4/6i, mTORi, and PI3Ki. For OS, CDK4/6i plus Ful500 ranked first; the SUCRA of ribociclib, abemaciclib, and palbociclib were 86.20%, 83.98%, and 78.52%, respectively. Alpelisib plus Ful500 (SUCRA=66.91%) ranked second but was not statistically different from CDK4/6i. The mTORi plus everolimus group had the best ORR (SUCRA=88.73%). In terms of safety, 81.56% of patients in the tucidinostat plus exemestane regimen developed neutropenia, suggesting strong hematological toxicity; 13.40% of patients developed grade 3-4 diarrhea after using abemaciclib plus Ful500. Conclusion: For second-line endocrine therapy in HR+/HER2− advanced/metastatic breast cancer, CDK4/6i is a better choice than mTORi, PI3Ki, HDACi, and Ful; it shows good PFS and OS outcomes and a low probability for serious adverse events.

Introduction: Pancreatic cancer is highly fatal and its incidence is rising worldwide. Its poor prognosis is attributed to a lack of effective diagnostic and therapeutic strategies. Dihydrotanshinone I (DHT), a phenanthrene quinone liposoluble compound from Salvia miltiorrhiza Bunge (Danshen), exerts anti-tumor effects by inhibiting cell proliferation, enhancing apoptosis, and inducing cell differentiation. However, its effects on pancreatic cancer are unclear. Methods: The role of DHT in the growth of tumor cells was explored using real-time cell analysis (RTCA), colony formation assay, and CCK-8. The effects of DHT on tumor cells invasion as well as migration were assessed by Transwell and migration assays. Expressions of pro-apoptosis and metastasis factors in tumor cells were examined using western blot. Tumor apoptosis rates were studied using flow cytometry. The anticancer effect of DHT in vivo was assessed by tumor transplantation into nude mice. Results: Our analyses show that DHT has a suppressive role in epithelial-mesenchymal transition (EMT), invasiveness, proliferation, as well as migratory ability of Patu8988 and PANC-1 cells via Hedgehog/Gli signaling. Moreover, it drives apoptosis via caspases/BCL2/BAX signaling. Experiments in nude mice transplanted with tumors have shown DHT to have anticancer effects in vivo. Conclusion: Our data show that DHT effectively suppresses pancreatic cancer cell proliferation as well as metastasis, and induces apoptosis via Hedgehog/Gli signaling. These effects have been reported to be dose- and time-dependent. Therefore, DHT can be exploited as a potential treatment for pancreatic cancer.

Background: Inhibiting cancer metabolism via glutaminase (GLS) is a promising strategy to disrupt tumor progression. However, the mechanism regarding GLS acetylation remains largely unknown. Methods: Mitochondrial protein isolation and glutaminase activity assay were used to examine GLS activity. RT-qPCR, western blot, sphere-formation, ALDH activity, and tumor-initiating assays were performed to evaluate the alteration of cell stemness. Co-IP and rescuing experiments were conducted to explore the underlying mechanisms. Results: In this study, we demonstrated that GLS acetylation is a vital post-translational modification that inhibits GLS activity in glioma. We identified GLS as deacetylated by HDAC4, a class II deacetylase. GLS acetylation stimulated the interaction between GLS and SIRT5, thereby promoting GLS ubiquitination and inhibiting GLS activity. Furthermore, GLS overexpression suppressed the stemness of glioma cells, which was rescued by the deacetylation of GLS. Conclusion: Our findings reveal a novel mechanism of GLS regulation by acetylation and ubiquitination that participate in glioma stemness.