Comprehensive review on how platinum- and taxane-based chemotherapy of ovarian cancer affects biology of normal cells

The clinical significance of mitochondrial calcium uniporter in gastric cancer patients and its preliminary exploration of the impact on mitochondrial function and metabolism

Objective

The objective of this study is to elucidate the influence of MCU on the clinical pathological features of GC patients, to investigate the function and mechanism of the mitochondrial calcium uptake transporter MCU in the initiation and progression of GC, and to explore its impact on the metabolic pathways and biosynthesis of mitochondria. The ultimate goal is to identify novel targets and strategies for the clinical management of GC patients.

Methods

Tumor and adjacent tissue specimens were obtained from 205 patients with gastric cancer, and immunohistochemical tests were performed to assess the expression of MCU and its correlation with clinical pathological characteristics and prognosis. Data from TCGA, GTEx and GEO databases were retrieved for gastric cancer patients, and bioinformatics analysis was utilized to investigate the association between MCU expression and clinical pathological features. Furthermore, we conducted an in-depth analysis of the role of MCU in GC patients. We investigated the correlation between MCU expression in GC and its impact on mitochondrial function, metabolism, biosynthesis, and immune cells. Additionally, we studied the proteins or molecules that interact with MCU.

Results

Our research revealed high expression of MCU in the GC tissues. This high expression was associated with poorer T and N staging, and indicated a worse disease-free survival period. MCU expression was positively correlated with mitochondrial function, mitochondrial metabolism, nucleotide, amino acid, and fatty acid synthesis metabolism, and negatively correlated with nicotinate and nicotinamide metabolism. Furthermore, the MCU also regulates the function of the mitochondrial oxidative respiratory chain. The MCU influences the immune cells of GC patients and regulates ROS generation, cell proliferation, apoptosis, and resistance to platinum-based drugs in gastric cancer cells.

Conclusion

High expression of MCU in GC indicates poorer clinical outcomes. The expression of the MCU are affected through impacts the function of mitochondria, energy metabolism, and cellular biosynthesis in gastric cancer cells, thereby influencing the growth and metastasis of gastric cancer cells. Therefore, the mitochondrial changes regulated by MCU could be a new focus for research and treatment of GC.

Cancer‑associated fibroblasts under therapy‑induced senescence in the tumor microenvironment (Review)

Current cancer treatments target tumor cells; however, the tumor microenvironment (TME) induces therapeutic resistance, tumor development and metastasis, thus rendering these treatments ineffective. Research on the TME has therefore concentrated on nonmalignant cells. Cancer-associated fibroblasts (CAFs) are a major TME component, which contribute to cancer progression due to their diverse origins, phenotypes and functions, including cancer cell invasion and migration, extracellular matrix remodeling, tumor metabolism modulation and therapeutic resistance. Standard cancer treatment typically exacerbates the senescence-associated secretory phenotype (SASP) of senescent cancer cells and nonmalignant cells that actively leak proinflammatory signals in the TME. Therapy-induced senescence may impair cancer cell activity and compromise treatment responsiveness. CAFs and SASP are well-studied in the formation and progression of cancer. The present review discusses the current data on CAF senescence caused by anticancer treatment and assesses how senescence-like CAFs affect tumor formation. The development of senolytic medication for aging stromal cells is also highlighted. Combining cancer therapies with senolytics may boost therapeutic effects and provide novel possibilities for research.

Plant-based natural products in cancer therapeutics

Various cells in our body regularly divide to replace old cells and dead cells. For a living cell to be growing, cell division and differentiation is highly essential. Cancer is characterised by uncontrollable cell division and invasion of other tissues due to dysregulation in the cell cycle. An accumulation of genetic changes or mutations develops through different physical (UV and other radiations), chemical (chewing and smoking of tobacco, chemical pollutants/mutagens), biological (viruses) and hereditary factors that can lead to cancer. Now, cancer is considered as a major death-causing factor worldwide. Due to advancements in technology, treatment like chemotherapy, radiation therapy, bone marrow transplant, immunotherapy, hormone therapy and many more in the rows. Although, it also has some side effects like fatigue, hair fall, anaemia, nausea and vomiting, constipation. Modern improved drug therapies come with severe side effects. There is need for safer, more effective, low-cost treatment with lesser side-effects. Biologically active natural products derived from plants are the emerging strategy to deal with cancer proliferation. Moreover, they possess anti-carcinogenic, anti-proliferative and anti-mutagenic properties with reduced side effects. They also detoxify and remove reactive substances formed by carcinogenic agents. In this article, we discuss different plant-based products and their mechanism of action against cancer.

Senescent T Cells in Age-Related Diseases

Age-induced alterations in human immunity are often considered deleterious and are referred to as immunosenescence. The immune system monitors the number of senescent cells in the body, while immunosenescence may represent the initiation of systemic aging. Immune cells, particularly T cells, are the most impacted and involved in age-related immune function deterioration, making older individuals more prone to different age-related diseases. T-cell senescence can impact the effectiveness of immunotherapies that rely on the immune system's function, including vaccines and adoptive T-cell therapies. The research and practice of using senescent T cells as therapeutic targets to intervene in age-related diseases are in their nascent stages. Therefore, in this review, we summarize recent related literature to investigate the characteristics of senescent T cells as well as their formation mechanisms, relationship with various aging-related diseases, and means of intervention. The primary objective of this article is to explore the prospects and possibilities of therapeutically targeting senescent T cells, serving as a valuable resource for the development of immunotherapy and treatment of age-related diseases.

Residual ANTXR1+ myofibroblasts after chemotherapy inhibit anti-tumor immunity via YAP1 signaling pathway

Although cancer-associated fibroblast (CAF) heterogeneity is well-established, the impact of chemotherapy on CAF populations remains poorly understood. Here we address this question in high-grade serous ovarian cancer (HGSOC), in which we previously identified 4 CAF populations. While the global content in stroma increases in HGSOC after chemotherapy, the proportion of FAP+ CAF (also called CAF-S1) decreases. Still, maintenance of high residual CAF-S1 content after chemotherapy is associated with reduced CD8+ T lymphocyte density and poor patient prognosis, emphasizing the importance of CAF-S1 reduction upon treatment. Single cell analysis, spatial transcriptomics and immunohistochemistry reveal that the content in the ECM-producing ANTXR1+ CAF-S1 cluster (ECM-myCAF) is the most affected by chemotherapy. Moreover, functional assays demonstrate that ECM-myCAF isolated from HGSOC reduce CD8+ T-cell cytotoxicity through a Yes Associated Protein 1 (YAP1)-dependent mechanism. Thus, efficient inhibition after treatment of YAP1-signaling pathway in the ECM-myCAF cluster could enhance CD8+ T-cell cytotoxicity. Altogether, these data pave the way for therapy targeting YAP1 in ECM-myCAF in HGSOC.

Mechanisms of carboplatin- and paclitaxel-dependent induction of premature senescence and pro-cancerogenic conversion of normal peritoneal mesothelium and fibroblasts

Carboplatin (CPT) and paclitaxel (PCT) are the optimal non-surgical treatment of epithelial ovarian cancer (EOC). Although their growth-restricting influence on EOC cells is well known, their impact on normal peritoneal cells, including mesothelium (PMCs) and fibroblasts (PFBs), is poorly understood. Here, we investigated whether, and if so, by what mechanism, CPT and PCT induce senescence of omental PMCs and PFBs. In addition, we tested whether PMC and PFB exposure to the drugs promotes the development of a pro-cancerogenic phenotype. The results showed that CPT and PCT induce G2/M growth arrest-associated senescence of normal peritoneal cells and that the strongest induction occurs when the drugs act together. PMCs senesce telomere-independently with an elevated p16 level and via activation of AKT and STAT3. In PFBs, telomeres shorten along with an induction of p21 and p53, and their senescence proceeds via the activation of ERK1/2. Oxidative stress in CPT + PCT-treated PMCs and PFBs is extensive and contributes causatively to their premature senescence. Both PMCs and PFBs exposed to CPT + PCT fuel the proliferation, migration, and invasion of established (A2780, OVCAR-3, SKOV-3) and primary EOCs, and this activity is linked with an overproduction of multiple cytokines altering the cancer cell transcriptome and controlled by p38 MAPK, NF-κB, STAT3, Notch1, and JAK1. Collectively, our findings indicate that CPT and PCT lead to iatrogenic senescence of normal peritoneal cells, which paradoxically and opposing therapeutic needs alters their phenotype towards pro-cancerogenic. It cannot be excluded that these adverse outcomes of chemotherapy may contribute to EOC relapse in the case of incomplete tumor eradication and residual disease initiation. © 2023 The Pathological Society of Great Britain and Ireland.

Ginsenoside 20(S)-Rg3 reduces KIF20A expression and promotes CDC25A proteasomal degradation in epithelial ovarian cancer

Background

Ginsenoside 20(S)-Rg3 shows promising tumor-suppressive effects in ovarian cancer via inhibiting NF-κB signaling. This study aimed to explore the downstream tumor suppressive mechanisms of ginsenoside Rg3 via this signaling pathway.

Materials and methods

A systematical screening was applied to examine the expression profile of 41 kinesin family member genes in ovarian cancer. The regulatory effect of ginsenoside Rg3 on KIF20A expression was studied. In addition, we explored interacting proteins of KIF20A and their molecular regulations in ovarian cancer. RNA-seq data from The Cancer Genome Atlas (TCGA) was used for bioinformatic analysis. Epithelial ovarian cancer cell lines SKOV3 and A2780 were used as in vitro and in vivo cell models. Commercial human ovarian cancer tissue arrays were used for immunohistochemistry staining.

Results

KIF20A is a biomarker of poor prognosis among the kinesin genes. It promotes ovarian cancer cell growth in vitro and in vivo. Ginsenoside Rg3 can suppress the transcription of KIF20A. GST pull-down and co-immunoprecipitation (IP) assays confirmed that KIF20A physically interacts with BTRC (β-TrCP1), a substrate recognition subunit for SCFβ-TrCP E3 ubiquitin ligase. In vitro ubiquitination and cycloheximide (CHX) chase assays showed that via interacting with BTRC, KIF20A reduces BTRC-mediated CDC25A poly-ubiquitination and enhances its stability. Ginsenoside Rg3 treatment partly abrogates KIF20A overexpression-induced CDC25A upregulation.

Conclusion

This study revealed a novel anti-tumor mechanism of ginsenoside Rg3. It can inhibit KIF20A transcription and promote CDC25A proteasomal degradation in epithelial ovarian cancer.

Nanocurcumin preserves kidney function and haematology parameters in DMBA-induced ovarian cancer treated with cisplatin via its antioxidative and anti-inflammatory effect in rats

CONTEXT

Cisplatin, as a first-line treatment for ovarian cancer, is associated with debilitating adverse effects, including nephrotoxic and haematotoxic effects.

OBJECTIVE

This study determines whether nanocurcumin, combined with cisplatin, would give additional benefit to kidney function and haematological parameters in rats with ovarian cancer.

MATERIALS AND METHODS

Twenty-five Wistar rats were divided into five untreated rats and 20-dimethylbenz(a)anthracene (DMBA)-induced ovarian cancer rats. The 20 ovarian cancer rats were divided into four treatment groups: vehicle, cisplatin, cisplatin-curcumin, and cisplatin-nanocurcumin. Cisplatin was given at the dose of 4 mg/kg BW once weekly, while curcumin or nanocurcumin was administered at 100 mg/kg BW daily for four weeks. At the end of treatment, we analysed kidney function, haematological parameters, and inflammatory and oxidative stress markers from plasma.

RESULTS

Nanocurcumin alleviates the increase in kidney function markers and abnormalities in haematological indices in rats treated with cisplatin. Compared to cisplatin-treated rats, plasma urea levels decreased from 66.4 to 47.7 mg/dL, creatinine levels lowered from 0.87 to 0.82 mg/dL, and neutrophil gelatinase-associated lipocalin (NGAL) levels declined from 8.51 to 3.59 mIU/mg protein. Furthermore, the therapy increased glutathione activities (from 2.02 to 3.23 U/µL), reduced lipid peroxidation (from 0.54 to 0.45 nmol/mL), and decreased plasma TNF-α (from 270.6 to 217.8 pg/mL).

CONCLUSIONS

Cisplatin with nanocurcumin in an ovarian cancer rat model may provide additional benefits as a preventive agent against renal impairment and cisplatin-induced haematological toxicity. However, further research is required to prove that using nanocurcumin for a more extended time would not affect its anticancer properties.

Molecular interactions of cucurbitacins A and B with anaplastic lymphoma kinase for lung cancer treatment

Lung cancer is a major global public health issue and the leading cause of cancer-related deaths. Several medications are commonly used to treat lung cancer, either alone or in combination with other treatments. The anaplastic lymphoma kinase (ALK) protein is one of several target proteins that are thought to be potential therapeutic targets in the context of lung cancer. Several ALK inhibitors have been identified, but many of these have been associated with side effects and toxicity concerns. In this study, we intend to computationally predict the binding potential of cucurbitacins (CBNs), A and B to the active pockets of ALK, in order to estimate their potential ALK inhibitors. Compared to CBN-A, which has a binding energy of -7.9 kcal/mol, CBN B exhibits significantly better binding efficacy with a binding energy of -8.1 kcal/mol. This is closely comparable to the binding energy of Crizotinib, which is -8.2 kcal/mol. The results of the molecular dynamics simulation indicated that the docked complexes remained stable for the duration of the 100 ns simulation period. CBN inhibited the proliferation of both non-small cell lung cancer cell lines, H1299 and A549, in a dose-dependent manner. CBN-B inhibited the proliferation of lung cancer cells, showing IC50 values of 0.08 µM for H1299 cells and 0.10 µM for A549 cells. The computational analyses provide strong evidence that CBN-B has the potential to act as a potent natural inhibitor against ALK, and could prove to be a valuable treatment option for lung cancer.Communicated by Ramaswamy H. Sarma.

Identification of Potential Protein Targets in Extracellular Vesicles Isolated from Chemotherapy-Treated Ovarian Cancer Cells

Despite the ongoing clinical trials and the introduction of novel treatments over the past few decades, ovarian cancer remains one of the most fatal malignancies in women worldwide. Platinum- and paclitaxel-based chemotherapy is effective in treating the majority of patients with ovarian cancer. However, more than 70% of patients experience recurrence and eventually develop chemoresistance. To improve clinical outcomes in patients with ovarian cancer, novel technologies must be developed for identifying molecular alterations following drug-based treatment of ovarian cancer. Recently, extracellular vesicles (EVs) have gained prominence as the mediators of tumor progression. In this study, we used mass spectrometry to identify the changes in EV protein signatures due to different chemotherapeutic agents used for treating ovarian cancer. By examining these alterations, we identified the specific protein induction patterns of cisplatin alone, paclitaxel alone, and a combination of cisplatin and paclitaxel. Specifically, we found that drug sensitivity was correlated with the expression levels of ANXA5, CD81, and RAB5C in patients receiving cisplatin with paclitaxel. Our findings suggest that chemotherapy-induced changes in EV protein signatures are crucial for the progression of ovarian cancer.

Mitochondrial metabolism: a predictive biomarker of radiotherapy efficacy and toxicity

INTRODUCTION

Radiotherapy is a mainstay of cancer treatment. Clinical studies revealed a heterogenous response to radiotherapy, from a complete response to even disease progression. To that end, finding the relative prognostic factors of disease outcomes and predictive factors of treatment efficacy and toxicity is essential. It has been demonstrated that radiation response depends on DNA damage response, cell cycle phase, oxygen concentration, and growth rate. Emerging evidence suggests that altered mitochondrial metabolism is associated with radioresistance.

METHODS

This article provides a comprehensive evaluation of the role of mitochondria in radiotherapy efficacy and toxicity. In addition, it demonstrates how mitochondria might be involved in the famous 6Rs of radiobiology.

RESULTS

In terms of this idea, decreasing the mitochondrial metabolism of cancer cells may increase radiation response, and enhancing the mitochondrial metabolism of normal cells may reduce radiation toxicity. Enhancing the normal cells (including immune cells) mitochondrial metabolism can potentially improve the tumor response by enhancing immune reactivation. Future studies are invited to examine the impacts of mitochondrial metabolism on radiation efficacy and toxicity. Improving radiotherapy response with diminishing cancer cells' mitochondrial metabolism, and reducing radiotherapy toxicity with enhancing normal cells' mitochondrial metabolism.

Relationships among Inflammatory Biomarkers and Objectively Assessed Physical Activity and Sleep during and after Chemotherapy for Gynecologic Malignancies

Little is known regarding associations between inflammatory biomarkers and objectively measured physical activity and sleep during and after chemotherapy for gynecologic cancer; thus, we conducted a longitudinal study to address this gap. Women with gynecologic cancer (patients) and non-cancer controls (controls) completed assessments before chemotherapy cycles 1, 3, and 6 (controls assessed contemporaneously), as well as at 6- and 12-month follow-ups. Physical activity and sleep were measured using wrist-worn actigraphs and sleep diaries, and blood was drawn to quantify circulating levels of inflammatory markers. Linear and quadratic random-effects mixed models and random-effects fluctuation mixed models were used to examine physical activity and sleep over time, as well as the associations with inflammatory biomarkers. On average, patients (n = 97) and controls (n = 104) were 62 and 58 years old, respectively. Compared to controls, patients were less active, more sedentary, had more time awake after sleep onset, and had lower sleep efficiency (p-values < 0.05). Across groups, higher levels of TNF-α were associated with more sedentary time and less efficient sleep (p-values ≤ 0.05). Higher levels of IL-1β, TNF-α, and IL-6 were associated with lower levels of light physical activity (p-values < 0.05). Associations between inflammatory biomarkers, physical activity, and sleep did not differ between patients and controls. Given these results, we speculate that inflammation may contribute to less physical activity and more sleep problems that persist even 12 months after completing chemotherapy.

Discovery and development of botanical natural products and their analogues as therapeutics for ovarian cancer

Covering: 2015 through the end of July 2022Ovarian cancer is one of the most common cancers affecting the female reproductive organs and has the highest mortality rate among gynecological cancers. Although botanical drugs and their derivatives, namely members of the taxane and camptothecin families, represent significant therapeutics currently available for the treatment of ovarian cancer, new drugs that have alternative mechanisms of action are still needed to combat the disease. For this reason, many efforts to identify additional novel compounds from botanical sources, along with the further development of existing therapeutics, have continued to appear in the literature. This review is designed to serve as a comprehensive look at both the currently available small-molecule therapeutic options and the recently reported botanically-derived natural products currently being studied and developed as potential future therapeutics that could one day be used against ovarian cancer. Specifically, key properties, structural features, and biological data are highlighted that are important for the successful development of potential agents. Recently reported examples are specifically discussed in the context of "drug discovery attributes," including the presence of structure-activity relationship, mechanism of action, toxicity, and pharmacokinetic studies, to help indicate the potential for future development and to highlight where these compounds currently exist in the development process. The lessons learned from both the successful development of the taxanes and camptothecins, as well as the strategies currently being employed for new drug development, are expected to ultimately help guide the future development of botanical natural products for ovarian cancer.

"Double-edged sword" effect of reactive oxygen species (ROS) in tumor development and carcinogenesis

Reactive oxygen species (ROS) are small reactive molecules produced by cellular metabolism and regulate various physiological and pathological functions. Many studies have shown that ROS plays an essential role in the proliferation and inhibition of tumor cells. Different concentrations of ROS can have a "double-edged sword" effect on the occurrence and development of tumors. A certain concentration of ROS can activate growth-promoting signals, enhance the proliferation and invasion of tumor cells, and cause damage to biomacromolecules such as proteins and nucleic acids. However, ROS can enhance the body's antitumor signal at higher levels by initiating oxidative stress-induced apoptosis and autophagy in tumor cells. This review analyzes ROS's unique bidirectional regulation mechanism on tumor cells, focusing on the key signaling pathways and regulatory factors that ROS affect the occurrence and development of tumors and providing ideas for an in-depth understanding of the mechanism of ROS action and its clinical application.

WNT-Conditioned Mechanism of Exit from Postchemotherapy Shock of Differentiated Tumour Cells

BACKGROUND

the present study aims to prove or disprove the hypothesis that the state of copy number aberration (CNA) activation of WNT signalling pathway genes accounts for the ability of differentiated tumour cells to emerge from postchemotherapy shock.

METHODS

In the first step, the CNA genetic landscape of breast cancer cell lines BT-474, BT-549, MDA-MB-231, MDA-MD-468, MCF7, SK-BR-3 and T47D, which were obtained from ATCC, was examined to rank cell cultures according to the degree of ectopic activation of the WNT signalling pathway. Then two lines of T47D with ectopic activation and BT-474 without activation were selected. The differentiated EpCAM+CD44-CD24-/+ cells of these lines were subjected to IL6 de-differentiation with formation of mammospheres on the background of cisplatin and WNT signalling inhibitor ICG-001.

RESULTS

it was found that T47D cells with ectopic WNT signalling activation after cisplatin exposure were dedifferentiated to form mammospheres while BT-474 cells without ectopic WNT-signalling activation did not form mammospheres. The dedifferentiation of T47D cells after cisplatin exposure was completely suppressed by the WNT signalling inhibitor ICG-001. Separately, ICG-001 reduced, but did not abolish, the ability to dedifferentiate in both cell lines.

CONCLUSIONS

these data support the hypothesis that the emergence of differentiated tumour cells from postchemotherapy shock after chemotherapy is due to ectopic activation of WNT signalling pathway genes.

Chemotherapy induced oxidative stress in the ovary: drug-dependent mechanisms and potential interventions†

Cancer incidence and relative survival are expected to increase over the next few decades. With the majority of patients receiving combinatorial chemotherapy, an increasing proportion of patients experience long-term side effects from treatment-including reproductive disorders and infertility. A limited number of studies have examined mechanisms of single-agent chemotherapy-induced gonadotoxicity, with chemotherapy-induced oxidative stress being implicated in the loss of reproductive functions. Current methods of female fertility preservation are costly, invasive, only moderately successful, and seldom presented to cancer patients. The potential of antioxidants to alleviate chemotherapy has been overlooked at a time when it is becoming increasingly important to develop strategies to protect reproductive functions during chemotherapy. This review will summarize the importance of reactive oxygen species homeostasis in reproduction, chemotherapy-induced mitochondrial dysfunction in oocytes, chemotherapy-induced oxidative stress, and several promising natural adjuvants.

Treatment for taxane-resistant cutaneous angiosarcoma: A multicenter study of 50 Japanese cases

Cutaneous angiosarcoma (CAS) is a rare and highly aggressive type of vascular tumor. Although chemoradiotherapy with taxanes is recognized as a first-line therapy for CAS, second-line therapy for CAS remains controversial. From the above findings, the efficacy and safety profiles of taxane-switch (change paclitaxel to docetaxel or vise), eribulin methylate, and pazopanib regimens in second-line chemotherapy were evaluated retrospectively in 50 Japanese taxane-resistant CAS patients. Although there was no significant difference in progression-free survival (P = 0.3528) among the regimens, the incidence of all adverse events (AEs) (P = 0.0386), as well as severe G3 or more AEs (P = 0.0477) was significantly higher in the eribulin methylate group and pazopanib group than in the taxane-switch group. The present data suggest that switching to another taxane should be considered for the treatment of taxane-resistant CAS in second-line therapy based on the safety profiles.

Peptide-Platinum(IV) Conjugation Minimizes the Negative Impact of Current Anticancer Chemotherapy on Nonmalignant Cells

The relative success of platinum (Pt)-based chemotherapy comes at the cost of severe adverse side effects and is associated with a high risk of pro-oncogenic activation in the tumor microenvironment. Here, we report the synthesis of C-POC, a novel Pt(IV) cell-penetrating peptide conjugate showing a reduced impact against nonmalignant cells. In vitro and in vivo evaluation using patient-derived tumor organoids and laser ablation inductively coupled plasma mass spectrometry indicates that C-POC maintains robust anticancer efficacy while displaying diminished accumulation in healthy organs and reduced adverse toxicity compared to the standard Pt-based therapy. Likewise, C-POC uptake is significantly lowered in the noncancerous cells populating the tumor microenvironment. This results in the downregulation of versican, a biomarker of metastatic spreading and chemoresistance that we found upregulated in patients treated with standard Pt-based therapy. Altogether, our findings underscore the importance of considering the off-target impact of anticancer treatment on normal cells to improve drug development and patient care.

Targeting ATAD3A-PINK1-mitophagy axis overcomes chemoimmunotherapy resistance by redirecting PD-L1 to mitochondria

Only a small proportion of patients with triple-negative breast cancer benefit from immune checkpoint inhibitor (ICI) targeting PD-1/PD-L1 signaling in combination with chemotherapy. Here, we discovered that therapeutic response to ICI plus paclitaxel was associated with subcellular redistribution of PD-L1. In our immunotherapy cohort of ICI in combination with nab-paclitaxel, tumor samples from responders showed significant distribution of PD-L1 at mitochondria, while non-responders showed increased accumulation of PD-L1 on tumor cell membrane instead of mitochondria. Our results also revealed that the distribution pattern of PD-L1 was regulated by an ATAD3A-PINK1 axis. Mechanistically, PINK1 recruited PD-L1 to mitochondria for degradation via a mitophagy pathway. Importantly, paclitaxel increased ATAD3A expression to disrupt proteostasis of PD-L1 by restraining PINK1-dependent mitophagy. Clinically, patients with tumors exhibiting high expression of ATAD3A detected before the treatment with ICI in combination with paclitaxel had markedly shorter progression-free survival compared with those with ATAD3A-low tumors. Preclinical results further demonstrated that targeting ATAD3A reset a favorable antitumor immune microenvironment and increased the efficacy of combination therapy of ICI plus paclitaxel. In summary, our results indicate that ATAD3A serves not only as a resistant factor for the combination therapy of ICI plus paclitaxel through preventing PD-L1 mitochondrial distribution, but also as a promising target for increasing the therapeutic responses to chemoimmunotherapy.

Profiling of Taxoid Compounds in Plant Cell Cultures of Different Species of Yew (Taxus spp.)

Plant cell cultures of various yew species are a profitable source of taxoids (taxane diterpenoids) with antitumor activity. So far, despite intensive studies, the principles of the formation of different groups of taxoids in cultured in vitro plant cells have not been fully revealed. In this study, the qualitative composition of taxoids of different structural groups was assessed in callus and suspension cell cultures of three yew species (Taxus baccata, T. canadensis, and T. wallichiana) and two T. × media hybrids. For the first time, 14-hydroxylated taxoids were isolated from the biomass of the suspension culture of T. baccata cells, and their structures were identified by high-resolution mass spectrometry and NMR spectroscopy as 7β-hydroxy-taxuyunnanin C, sinenxane C, taxuyunnanine C, 2α,5α,9α,10β,14β-pentaacetoxy-4(20), 11-taxadiene, and yunnanxane. UPLC-ESI-MS screening of taxoids was performed in more than 20 callus and suspension cell lines originating from different explants and grown in over 20 formulations of nutrient media. Regardless of the species, cell line origin, and conditions, most of the investigated cell cultures retained the ability to form taxane diterpenoids. Nonpolar 14-hydroxylated taxoids (in the form of polyesters) were predominant under in vitro culture conditions in all cell lines. These results, together with the literature data, suggest that dedifferentiated cell cultures of various yew species retain the ability to synthesize taxoids, but predominantly of the 14-OH taxoid group compared to the 13-OH taxoids found in plants.

Long-term platinum-based drug accumulation in cancer-associated fibroblasts promotes colorectal cancer progression and resistance to therapy

A substantial proportion of cancer patients do not benefit from platinum-based chemotherapy (CT) due to the emergence of drug resistance. Here, we apply elemental imaging to the mapping of CT biodistribution after therapy in residual colorectal cancer and achieve a comprehensive analysis of the genetic program induced by oxaliplatin-based CT in the tumor microenvironment. We show that oxaliplatin is largely retained by cancer-associated fibroblasts (CAFs) long time after the treatment ceased. We determine that CT accumulation in CAFs intensifies TGF-beta activity, leading to the production of multiple factors enhancing cancer aggressiveness. We establish periostin as a stromal marker of chemotherapeutic activity intrinsically upregulated in consensus molecular subtype 4 (CMS4) tumors and highly expressed before and/or after treatment in patients unresponsive to therapy. Collectively, our study underscores the ability of CT-retaining CAFs to support cancer progression and resistance to treatment.

NK cell-derived exosomes enhance the anti-tumor effects against ovarian cancer by delivering cisplatin and reactivating NK cell functions

Exosomes are membranous vesicles actively secreted by almost all cells and they deliver certain intracellular molecules, including nucleic acids, proteins, and lipids, to target cells. They are also considered to be good carriers for drug delivery due to their biocompatibility, high permeability, low immunogenicity, and low toxicity. Exosomes from immune cells were also reported to have immunomodulatory activities. Herein we evaluated the application of exosomes derived from expanded natural killer cells (eNK-EXO) for the treatment of ovarian cancer (OC). We demonstrate that eNK-EXO express typical protein markers of natural killer (NK) cells, can be preferentially uptaken by SKOV3 cells, and display cytotoxicity against OC cells. Furthermore, eNK-EXO loaded with cisplatin could sensitize drug-resistant OC cells to the anti-proliferation effect of cisplatin. In addition, we show that eNK-EXO could activate NK cells from immunosuppressive tumor microenvironment, the mechanism of which is explored by transcriptional analysis. In summary, eNK-EXO exhibit anti-tumor activity against OC on its own, could be used to deliver cisplatin and enhance its cytotoxic effect against drug-resistant OC cells and also reverse the immunosuppression of NK cells, which may lead to great prospect of using eNK-EXO in the treatment of OC in the clinic. Our work also builds a strong foundation for further evaluation of eNK-EXO in other solid tumor therapies.

CAR T-Cell Immunotherapy Treating T-ALL: Challenges and Opportunities

T-cell acute lymphoblastic leukemia (T-ALL), a form of T-cell malignancy, is a typically aggressive hematological malignancy with high rates of disease relapse and a poor prognosis. Current guidelines do not recommend any specific treatments for these patients, and only allogeneic stem cell transplant, which is associated with potential risks and toxicities, is a curative therapy. Recent clinical trials showed that immunotherapies, including monoclonal antibodies, checkpoint inhibitors, and CAR T therapies, are successful in treating hematologic malignancies. CAR T cells, which specifically target the B-cell surface antigen CD19, have demonstrated remarkable efficacy in the treatment of B-cell acute leukemia, and some progress has been made in the treatment of other hematologic malignancies. However, the development of CAR T-cell immunotherapy targeting T-cell malignancies appears more challenging due to the potential risks of fratricide, T-cell aplasia, immunosuppression, and product contamination. In this review, we discuss the current status of and challenges related to CAR T-cell immunotherapy for T-ALL and review potential strategies to overcome these limitations.

Will the Interactions of Some Platinum (II)-Based Drugs with B-Vitamins Reduce Their Therapeutic Effect in Cancer Patients? Comparison of Chemotherapeutic Agents such as Cisplatin, Carboplatin and Oxaliplatin-A Review

Pt (II) derivatives show anti-cancer activity by interacting with nucleobases of DNA, thus causing some spontaneous and non-spontaneous reactions. As a result, mono- and diaqua products are formed which further undergo complexation with guanine or adenine. Consequently, many processes are triggered, which lead to the death of the cancer cell. The theoretical and experimental studies confirm that such types of interactions can also occur with other chemical compounds. The vitamins from B group have a similar structure to the nucleobases of DNA and have aromatic rings with single-pair orbitals. Theoretical and experimental studies were performed to describe the interactions of B vitamins with Pt (II) derivatives such as cisplatin, oxaliplatin and carboplatin. The obtained results were compared with the values for guanine. Two levels of simulations were implemented at the theoretical level, namely, B3LYP/6-31G(d,p) with LANL2DZ bases set for platinum atoms and MN15/def2-TZVP. The polarizable continuum model (IEF-PCM preparation) and water as a solvent were used. UV-Vis spectroscopy was used to describe the drug-nucleobase and drug-B vitamin interactions. Values of the free energy (ΔG_r) show spontaneous reactions with mono- and diaqua derivatives of cisplatin and oxaliplatin; however, interactions with diaqua derivatives are more preferable. The strength of these interactions was also compared. Carboplatin products have the weakest interaction with the studied structures. The presence of non-covalent interactions was demonstrated in the tested complexes. A good agreement between theory and experiment was also demonstrated.

Modulation of redox homeostasis: A strategy to overcome cancer drug resistance

Cancer treatment is hampered by resistance to conventional therapeutic strategies, including chemotherapy, immunotherapy, and targeted therapy. Redox homeostasis manipulation is one of the most effective innovative treatment techniques for overcoming drug resistance. Reactive oxygen species (ROS), previously considered intracellular byproducts of aerobic metabolism, are now known to regulate multiple signaling pathways as second messengers. Cancer cells cope with elevated amounts of ROS during therapy by upregulating the antioxidant system, enabling tumor therapeutic resistance via a variety of mechanisms. In this review, we aim to shed light on redox modification and signaling pathways that may contribute to therapeutic resistance. We summarized the molecular mechanisms by which redox signaling-regulated drug resistance, including altered drug efflux, action targets and metabolism, enhanced DNA damage repair, maintained stemness, and reshaped tumor microenvironment. A comprehensive understanding of these interrelationships should improve treatment efficacy from a fundamental and clinical research point of view.

Fraxetin Interacts Additively with Cisplatin and Mitoxantrone, Antagonistically with Docetaxel in Various Human Melanoma Cell Lines-An Isobolographic Analysis

Malignant melanoma is a skin cancer characterized by rapid development, poor prognosis and high mortality. Due to the frequent drug resistance and/or early metastases in melanoma, new therapeutic methods are urgently needed. The study aimed at assessing the cytotoxic and antiproliferative effects of scoparone and fraxetin in vitro, when used alone and in combination with three cytostatics: cisplatin, mitoxantrone, and docetaxel in four human melanoma cell lines. Our experiments showed that scoparone in the concentration range tested up to 200 µM had no significant effect on the viability of human malignant melanoma (therefore, it was not possible to evaluate it in combination with other cytostatics), while fraxetin inhibited cell proliferation with IC₅₀ doses in the range of 32.42-73.16 µM, depending on the cell line. Isobolographic analysis allowed for the assessment of the interactions between the studied compounds. Importantly, fraxetin was not cytotoxic to normal keratinocytes (HaCaT) and melanocytes (HEMa-LP), although it slightly inhibited their viability at high concentrations. The combination of fraxetin with cisplatin and mitoxantrone showed the additive interaction, which seems to be a promising direction in melanoma therapy. Unfortunately, the combination of fraxetin with docetaxel may not be beneficial due to the antagonistic antiproliferative effect of both drugs used in the mixture.

Nanoparticle-Based Follistatin Messenger RNA Therapy for Reprogramming Metastatic Ovarian Cancer and Ameliorating Cancer-Associated Cachexia

This study presents the first messenger RNA (mRNA) therapy for metastatic ovarian cancer and cachexia-induced muscle wasting based on lipid nanoparticles that deliver follistatin (FST) mRNA predominantly to cancer clusters following intraperitoneal administration. The secreted FST protein, endogenously synthesized from delivered mRNA, efficiently reduces elevated activin A levels associated with aggressive ovarian cancer and associated cachexia. By altering the cancer cell phenotype, mRNA treatment prevents malignant ascites, delays cancer progression, induces the formation of solid tumors, and preserves muscle mass in cancer-bearing mice by inhibiting negative regulators of muscle mass. Finally, mRNA therapy provides synergistic effects in combination with cisplatin, increasing the survival of mice and counteracting muscle atrophy induced by chemotherapy and cancer-associated cachexia. The treated mice develop few nonadherent tumors that are easily resected from the peritoneum. Clinically, this nanomedicine-based mRNA therapy can facilitate complete cytoreduction, target resistance, improve resilience during aggressive chemotherapy, and improve survival in advanced ovarian cancer.

Highly Charged Ru(II) Polypyridyl Complexes as Photosensitizer Agents in Photodynamic Therapy of Epithelial Ovarian Cancer Cells

Ovarian cancer recurrence is frequent and associated with chemoresistance, leading to extremely poor prognosis. Herein, we explored the potential anti-cancer effect of a series of highly charged Ru(II)-polypyridyl complexes as photosensitizers in photodynamic therapy (PDT), which were able to efficiently sensitize the formation of singlet oxygen upon irradiation (Ru12+ and Ru22+) and to produce reactive oxygen species (ROS) in their corresponding dinuclear metal complexes with the Fenton active Cu(II) ion/s ([CuRu1]4+ and [Cu2Ru2]6+). Their cytotoxic and anti-tumor effects were evaluated on human ovarian cancer A2780 cells both in the absence or presence of photoirradiation, respectively. All the compounds tested were well tolerated under dark conditions, whereas they switched to exert anti-tumor activity following photoirradiation. The specific effect was mediated by the onset of programed cell death, but only in the case of Ru12+ and Ru22+ was preceded by the loss of mitochondrial membrane potential soon after photoactivation and ROS production, thus supporting the occurrence of apoptosis via type II photochemical reactions. Thus, Ru(II)-polypyridyl-based photosensitizers represent challenging tools to be further investigated in the identification of new therapeutic approaches to overcome the innate chemoresistance to platinum derivatives of some ovarian epithelial cancers and to find innovative drugs for recurrent ovarian cancer.

Identifying Hub Genes Associated with Neoadjuvant Chemotherapy Resistance in Breast Cancer and Potential Drug Repurposing for the Development of Precision Medicine

Breast cancer is the second leading cause of morbidity and mortality in women worldwide. Despite advancements in the clinical application of neoadjuvant chemotherapy (NAC), drug resistance remains a major concern hindering treatment efficacy. Thus, identifying the key genes involved in driving NAC resistance and targeting them with known potential FDA-approved drugs could be applied to advance the precision medicine strategy. With this aim, we performed an integrative bioinformatics study to identify the key genes associated with NAC resistance in breast cancer and then performed the drug repurposing to identify the potential drugs which could use in combination with NAC to overcome drug resistance. In this study, we used publicly available RNA-seq datasets from the samples of breast cancer patients sensitive and resistant to chemotherapy and identified a total of 1446 differentially expressed genes in NAC-resistant breast cancer patients. Next, we performed gene co-expression network analysis to identify significantly co-expressed gene modules, followed by MCC (Multiple Correlation Clustering) clustering algorithms and identified 33 key hub genes associated with NAC resistance. mRNA–miRNA network analysis highlighted the potential impact of these hub genes in altering the regulatory network in NAC-resistance breast cancer cells. Further, several hub genes were found to be significantly involved in the poor overall survival of breast cancer patients. Finally, we identified FDA-approved drugs which could be useful for potential drug repurposing against those hub genes. Altogether, our findings provide new insight into the molecular mechanisms of NAC resistance and pave the way for drug repurposing techniques and personalized treatment to overcome NAC resistance in breast cancer.

PUMA overexpression dissociates thioredoxin from ASK1 to activate the JNK/BCL-2/BCL-XL pathway augmenting apoptosis in ovarian cancer

ASK1-JNK signaling promotes mitochondrial dysfunction-mediated apoptosis, but the bridge between JNK and apoptosis is not fully understood. PUMA induces apoptosis through BAX/BAK. Our previous study suggests a therapeutic potential of PUMA for ovarian cancer. However, whether and how PUMA activates ASK1 remains unclear. Here, we found for the first time that PUMA activated ASK1 by dissociating thioredoxin (TRX) from ASK1, however, it neither interacted with ASK1 nor TRX. Furthermore, PUMA overexpression caused ROS release from mitochondrial. H₂O₂ significantly impaired the interaction of ASK1 with TRX, whereas ROS scavenger NAC effectively abrogated the H₂O₂ effect, partly rescued PUMA-interfered interaction of ASK1 with TRX, and also abolished ASK1 phosphorylation. Interestingly, PUMA could not impair the association of ASK1 with TRX-C32S or TRX-C35S, two TRX mutants which are no longer oxidized in response to ROS. We further showed that PUMA activated ASK1-JNK axis to phosphorylate BCL-2 and BCL-XL, further augmenting apoptosis of ovarian cancer cells. In vivo, PUMA adenovirus combined with paclitaxel significantly inhibited intrinsically cisplatin-resistant ovarian cancer growth, and caused phosphorylation of BCL-2 and BCL-XL. Our results from human ovarian cancer TMA chips also revealed a positive correlation between PUMA expression and the phosphorylation of BCL-2 and BCL-XL. More importantly, all patients had no distal metastasis, implying a possibly clinical significance. Collectively, our results reveal a new pro-apoptotic signal amplification mechanism for PUMA by which PUMA overexpression first induces ROS-mediated dissociation of TRX from ASK1, and then causes JNK activation-triggering BCL-2/BCL-XL phosphorylation, ultimately augmenting apoptosis in ovarian cancer.

Acquisition of taxane resistance by p53 inactivation in ovarian cancer cells

Ovarian cancer is one of the most common gynecologic malignancies in women and has a poor prognosis. Taxanes are a class of standard first-line chemotherapeutic agents for the treatment of ovarian cancer. However, tumor-intrinsic and acquired resistance to taxanes poses major challenges to improving clinical outcomes. Hence, there is an urgent clinical need to understand the mechanisms of resistance in order to discover potential biomarkers and therapeutic strategies to increase taxane sensitivity in ovarian cancer. Here, we report the identification of an association between the TP53 status and taxane sensitivity in ovarian cancer cells through complementary experimental and informatics approaches. We found that TP53 inactivation is associated with taxane resistance in ovarian cancer cells, supported by the evidence from (i) drug sensitivity profiling with bioinformatic analysis of large-scale cancer therapeutic response and genomic datasets and (ii) gene signature identification based on experimental isogenic cell line models. Further, our studies revealed TP53-dependent gene expression patterns, such as overexpression of ACSM3, as potential predictive biomarkers of taxane resistance in ovarian cancer. The TP53-dependent hyperactivation of the WNT/β-catenin pathway discovered herein revealed a potential vulnerability to exploit in developing combination therapeutic strategies. Identification of this genotype-phenotype relationship between the TP53 status and taxane sensitivity sheds light on TP53-directed patient stratification and therapeutic discoveries for ovarian cancer treatment.

Alpha Mangostin and Cisplatin as Modulators of Exosomal Interaction of Ovarian Cancer Cell with Fibroblasts

The diversity of exosomes and their role in the microenvironment make them an important point of interest in the development of cancer. In our study, we evaluated the effect of exosomes derived from ovarian cancer cells on gene expression in fibroblasts, including genes involved in metastasis. We also attempted to evaluate the indirect effect of cisplatin and/or α-mangostin on metastasis. In this aspect, we verified the changes induced by the drugs we tested on vesicular transfer associated with the release of exosomes by cells. We isolated exosomes from ovarian cancer cells treated and untreated with drugs, and then normal human fibroblasts were treated with the isolated exosomes. Changes in the expression of genes involved in the metastasis process were then examined. In our study, we observed altered expression of genes involved in various steps of the metastasis process (including genes related to cell adhesion, genes related to the interaction with the extracellular matrix, the cell cycle, cell growth and proliferation, and apoptosis). We have shown that α-mangostin and/or cisplatin, as chemotherapeutic agents, not only directly affect tumor cells but may also indirectly (via exosomes) contribute to delaying metastasis development.

Cancer chemotherapy: insights into cellular and tumor microenvironmental mechanisms of action

Chemotherapy has historically been the mainstay of cancer treatment, but our understanding of what drives a successful therapeutic response remains limited. The diverse response of cancer patients to chemotherapy has been attributed principally to differences in the proliferation rate of the tumor cells, but there is actually very little experimental data supporting this hypothesis. Instead, other mechanisms at the cellular level and the composition of the tumor microenvironment appear to drive chemotherapy sensitivity. In particular, the immune system is a critical determinant of chemotherapy response with the depletion or knock-out of key immune cell populations or immunological mediators completely abrogating the benefits of chemotherapy in pre-clinical models. In this perspective, we review the literature regarding the known mechanisms of action of cytotoxic chemotherapy agents and the determinants of response to chemotherapy from the level of individual cells to the composition of the tumor microenvironment. We then summarize current work toward the development of dynamic biomarkers for response and propose a model for a chemotherapy sensitive tumor microenvironment.

Interfering with the expression of EEF1D gene enhances the sensitivity of ovarian cancer cells to cisplatin

Background

Eukaryotic translation elongation factors 1 δ (EEF1D), has garnered much attention with regards to their role in the drug resistance of cancers. In this paper, we investigated the effects and mechanisms of increasing the sensitivity of ovarian cancer cells to cisplatin or cis-dichlorodiammine platinum (DDP) by knockdown and knockout of EEF1D gene in cellular and animal models.

Methods

The EEF1D gene was knocked-down or -out by siRNA or CRISPR/Cas9 respectively in human ovarian cancer cell SKOV3, DDP-resistant subline SKOV3/DDP, and EEF1D gene in human primary ovarian cancer cell from 5 ovarian cancer patients with progressive disease/stable disease (PD/SD) was transiently knocked down by siRNA interference. The mice model bearing xenografted tumor was established with subcutaneous inoculation of SKOV3/DDP.

Results

The results show that reducing or removing EEF1D gene expression significantly increased the sensitivity of human ovarian cancer cells to DDP in inhibiting viability and inducing apoptosis in vitro and in vivo, and also boosted DDP to inhibit xenografted tumor growth. Interfering with EEF1D gene expression in mice xenografted tumor significantly affected the levels of OPTN, p-Akt, Bcl-2, Bax, cleaved caspase-3 and ERCC1 compared to DDP treated mice alone, and had less effect on PI3K, Akt and caspase-3.

Conclusions

The knocking down or out EEF1D gene expression could enhance the sensitivity of ovarian cancer cells to DDP partially, which may be achieved via inactivating the PI3K/AKT signaling pathway, thus inducing cell apoptosis and decreasing repairment of DNA damage. Our study provides a novel therapeutic strategy for the treatment of ovarian cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09699-7.

Off-label use of paclitaxel and pembrolizumab in a case of platinum refractory epithelial ovarian cancer and extensive thromboembolism

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Management of platinum refractory ovarian cancer is challenging.

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Extensive venous thromboembolism precludes anti-angiogenic combination chemotherapy.

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Weekly paclitaxel and immune-checkpoint inhibitor combination provides a durable tumor control option.

The Effect of α-Mangostin and Cisplatin on Ovarian Cancer Cells and the Microenvironment

Ovarian cancer is one of the cancers that, unfortunately, is detected at a late stage of development. The current use of treatment has many side effects. Notably, up to 20% of patients show cisplatin resistance. We assess the effects of cisplatin and/or α-mangostin, a natural plant derivative, on ovarian cancer cells and on the cancer cell microenvironment. The effect of cisplatin and/or α-mangostin on the following cells of ovarian cancer lines: A2780, TOV-21G, and SKOV-3 was verified using the XTT cytotoxicity assay. The separate and combined effects of tested drugs on ovarian cancer cell viability were assessed. We assessed the influence of chemotherapeutic agents on the possibility of modulating the microenvironment. For this purpose, we isolated exosomes from drug-treated and untreated ovarian cancer cells. We estimated the differences in the amounts of exosomes released from cancer cells (NTA technique). We also examined the effects of isolated exosome fractions on normal human cells (NHDF human fibroblast line). In the present study, we demonstrate that treatment of A2780, SKOV-3, and TOV-21G cells with α-mangostin in combination with cisplatin can allow a reduction in cisplatin concentration while maintaining the same cytotoxic effect. Ovarian cancer cells release a variable number of exosomes into the microenvironment when exposed to α-mangostin and/or cisplatin. However, it is important to note that the cargo carried by exosomes released from drug-treated cells may be significantly different.

Protective effect of food derived nutrients on cisplatin nephrotoxicity and its mechanism

Platinum-based metal complexes, especially cisplatin (cis-diamminedichloroplatinum II, CDDP), possess strong anticancer properties and a broad anticancer spectrum. However, the clinical application of CDDP has been limited by its side effects including nephrotoxicity, ototoxicity, and neurotoxicity. Furthermore, the therapeutic effects of current clinical protocols are imperfect. Accordingly, it is essential to identify key targets and effective clinical protocols to restrict CDDP-induced nephrotoxicity. Herein, we first analyzed the relevant molecular mechanisms during the process of CDDP-induced nephrotoxicity including oxidative stress, apoptosis, and inflammation. Evidence from current studies was collected and potential targets and clinical protocols are summarized. The evidence indicates an efficacious role of nutrition-based substances in CDDP-induced renal injury.

Magnetization transfer imaging of ovarian cancer: initial experiences of correlation with tissue cellularity and changes following neoadjuvant chemotherapy

Objectives

To investigate the relationship between magnetization transfer (MT) imaging and tissue macromolecules in high-grade serous ovarian cancer (HGSOC) and whether MT ratio (MTR) changes following neoadjuvant chemotherapy (NACT).

Methods

This was a prospective observational study. 12 HGSOC patients were imaged before treatment. MTR was compared to quantified tissue histology and immunohistochemistry. For a subset of patients (n = 5), MT imaging was repeated after NACT. The Shapiro-Wilk test was used to assess for normality of data and Spearman's rank-order or Pearson's correlation tests were then used to compare MTR with tissue quantifications. The Wilcoxon signed-rank test was used to assess for changes in MTR after treatment.

Results

Treatment-naïve tumour MTR was 21.9 ± 3.1% (mean ± S.D.). MTR had a positive correlation with cellularity, rho = 0.56 (p < 0.05) and a negative correlation with tumour volume, ρ = -0.72 (p = 0.01). MTR did not correlate with the extracellular proteins, collagen IV or laminin (p = 0.40 and p = 0.90). For those patients imaged before and after NACT, an increase in MTR was observed in each case with mean MTR 20.6 ± 3.1% (median 21.1) pre-treatment and 25.6 ± 3.4% (median 26.5) post-treatment (p = 0.06).

Conclusion

In treatment-naïve HGSOC, MTR is associated with cellularity, possibly reflecting intracellular macromolecular concentration. MT may also detect the HGSOC response to NACT, however larger studies are required to validate this finding.

Advances in knowledge

MTR in HGSOC is influenced by cellularity. This may be applied to assess for cell changes following treatment.

Collateral responses to classical cytotoxic chemotherapies are heterogeneous and sensitivities are sparse

Chemotherapy resistance is a major obstacle to curing cancer patients. Combination drug regimens have shown promise as a method to overcome resistance; however, to date only some cancers have been cured with this method. Collateral sensitivity-the phenomenon whereby resistance to one drug is co-occurrent with sensitivity to a second drug-has been gaining traction as a promising new concept to guide rational design of combination regimens. Here we evolved over 100 subclones of the Eµ-Myc; p19^ARF-/- cell line to be resistant to one of four classical chemotherapy agents: doxorubicin, vincristine, paclitaxel, and cisplatin. We then surveyed collateral responses to acquisition of resistance to these agents. Although numerous collateral sensitivities have been documented for antibiotics and targeted cancer therapies, we observed only one collateral sensitivity: half of cell lines that acquired resistance to paclitaxel also acquired a collateral sensitivity to verapamil. However, we found that the mechanism of this collateral sensitivity was unrelated to the mechanism of paclitaxel resistance. Interestingly, we observed heterogeneity in the phenotypic response to acquisition of resistance to most of the drugs we tested, most notably for paclitaxel, suggesting the existence of multiple different states of resistance. Surprisingly, this phenotypic heterogeneity in paclitaxel resistant cell lines was unrelated to transcriptomic heterogeneity among those cell lines. These features of phenotypic and transcriptomic heterogeneity must be taken into account in future studies of treated tumor subclones and in design of chemotherapy combinations.

SIAH1 reverses chemoresistance in epithelial ovarian cancer via ubiquitination of YBX-1

Chemoresistance is a severe outcome among patients with epithelial ovarian cancer (EOC) that leads to a poor prognosis. YBX-1 has been shown to cause treatment failure and cancer progression in EOC. However, strategies that directly target YBX-1 are not yet conceivable. Here, we identified that SIAH1 which was downregulated in chemoresistant EOC samples and cell lines functioned as novel E3 ligases to trigger degradation of YBX-1 at cytoplasm by RING finger domain. Mechanistic studies show that YBX-1 was ubiquitinated by SIAH1 at lys304 that lead to the instability of its target m5C-modified mRNAs, thus sensitized EOC cells to cDDP. Overexpression of SIAH1 enhanced the antitumor efficacy of cisplatin in vitro and in vivo, which were partially impaired by ectopic expression of YBX-1 or depletion of YBX-1 ubiquitination. In summary, our data identify the SIAH1/YBX-1 interaction as a therapeutic target for overcoming EOC chemoresistance.

Knowns and Unknowns about CAR-T Cell Dysfunction

Simple Summary

The primary issue of adoptive cell therapy is the poor in vivo persistence. In this context, it is necessary to clarify the fundamental mechanisms of T cell dysfunction. Here we review common dysfunctional states, including exhaustion and senescence, and discuss the challenges associated with phenotypical characterization of these T cell subsets. We overview the heterogeneity among exhausted T cells as well as mechanisms by which T cells get reinvigorated by checkpoint inhibitors. We emphasize that some cancers not responding to such treatment may activate distinct T cell dysfunction programs. Finally, we describe the dysfunction-promoting mechanisms specific for CAR-T cells and the ways to mitigate them.

Abstract

Immunotherapy using chimeric antigen receptor (CAR) T cells is a promising option for cancer treatment. However, T cells and CAR-T cells frequently become dysfunctional in cancer, where numerous evasion mechanisms impair antitumor immunity. Cancer frequently exploits intrinsic T cell dysfunction mechanisms that evolved for the purpose of defending against autoimmunity. T cell exhaustion is the most studied type of T cell dysfunction. It is characterized by impaired proliferation and cytokine secretion and is often misdefined solely by the expression of the inhibitory receptors. Another type of dysfunction is T cell senescence, which occurs when T cells permanently arrest their cell cycle and proliferation while retaining cytotoxic capability. The first section of this review provides a broad overview of T cell dysfunctional states, including exhaustion and senescence; the second section is focused on the impact of T cell dysfunction on the CAR-T therapeutic potential. Finally, we discuss the recent efforts to mitigate CAR-T cell exhaustion, with an emphasis on epigenetic and transcriptional modulation.

Identifying Mitotic Kinesins as Potential Prognostic Biomarkers in Ovarian Cancer Using Bioinformatic Analyses

Ovarian cancer (OC) is characterized by late-stage presentation, chemoresistance, and poor survival. Evaluating the prognosis of OC patients via effective biomarkers is essential to manage OC progression and to improve survival; however, it has been barely established. Here, we intend to identify differentially expressed genes (DEGs) as potential prognostic biomarkers of OC via bioinformatic analyses. Initially, a total of thirteen DEGs were extracted from different public databases as candidates. The expression of KIF20A, one of the DEGs, was correlated with a worse outcome of OC patients. The functional correlation of the DEGs with mitosis and the prognostic value of KIF20A imply a high correlation between mitotic kinesins (KIFs) and OC development. Finally, we found that KIF20A, together with the other nine mitotic KIFs (4A, 11, 14, 15, 18A, 18B, 23, C1, and2C) were upregulated and activated in OC tissues. Among the ten, seven overexpressed mitotic KIFs (11, 14, 18B, 20A, 23, and C1) were correlated with unfavorable clinical prognosis. Moreover, KIF20A and KIF23 overexpression was associated with worse prognosis in OC patients treated with platinum/taxol chemotherapy, while OCs overexpressing mitotic KIFs (11, 15, 18B, and C1) were resistant to MAPK pathway inhibitors. In conclusion, worse outcomes of OC patients were correlated with overexpression of several mitotic KIFs, which may serve both as prognostic biomarkers and therapeutic targets for OC.

Paclitaxel-Induced Epidermal Alterations: An In Vitro Preclinical Assessment in Primary Keratinocytes and in a 3D Epidermis Model

Paclitaxel is a microtubule-stabilizing chemotherapeutic agent approved for the treatment of ovarian, non-small cell lung, head, neck, and breast cancers. Despite its beneficial effects on cancer and widespread use, paclitaxel also damages healthy tissues, including the skin. However, the mechanisms that drive these skin adverse events are not clearly understood. In the present study, we demonstrated, by using both primary epidermal keratinocytes (NHEK) and a 3D epidermis model, that paclitaxel impairs different cellular processes: paclitaxel increased the release of IL-1α, IL-6, and IL-8 inflammatory cytokines, produced reactive oxygen species (ROS) release and apoptosis, and reduced the endothelial tube formation in the dermal microvascular endothelial cells (HDMEC). Some of the mechanisms driving these adverse skin events in vitro are mediated by the activation of toll-like receptor 4 (TLR-4), which phosphorylate transcription of nuclear factor kappa B (NF-κb). This is the first study analyzing paclitaxel effects on healthy human epidermal cells with an epidermis 3D model, and will help in understanding paclitaxel's effects on the skin.

Bioinformatic Analyses of the Ferroptosis-Related lncRNAs Signature for Ovarian Cancer

Both ferroptosis and lncRNAs are significant for ovarian cancer (OC). Whereas, the study of ferroptosis-related lncRNAs (FRLs) still few in ovarian cancer. We first constructed an FRL-signature for patients with OC in the study. A total of 548 FRLs were identified for univariate Cox regression analysis, and 21 FRLs with significant prognosis were identified. The prognostic characteristics of nine FRLs was constructed and validated, showing opposite prognosis in two subgroups based on risk scores. The multivariate Cox regression analysis and nomogram further verified the prognostic value of the risk model. By calculating ferroptosis score through ssGSEA, we found that patients with higher risk scores exhibited higher ferroptosis scores, and high ferroptosis score was a risk factor. There were 40 microenvironment cells with significant differences in the two groups, and the difference of Stromal score between the two groups was statistically significant. Six immune checkpoint genes were expressed at different levels in the two groups. In addition, five m6A regulators (FMR1, HNRNPC, METTL16, METTL3, and METTL5) were higher expressed in the low-risk group. GSEA revealed that the risk model was associated with tumor-related pathways and immune-associated pathway. We compared the sensitivity of chemotherapy drugs between the two risk groups. We also explored the co-expression, ceRNA relation, cis and trans interaction of ferroptosis-related genes and lncRNAs, providing a new idea for the regulatory mechanisms of FRLs. Moreover, the nine FRLs were selected for detecting their expression levels in OC cells and tissues.

Oxidative stress in cancer therapy: Friend or enemy?

Excessive cellular oxidative stress is widely perceived as a key factor in pathophysiological conditions and cancer development. Healthy cells use several mechanisms to maintain intracellular levels of reactive oxygen species (ROS) and overall redox homeostasis to avoid damage to DNA, proteins, and lipids. Cancer cells, in contrast, exhibit elevated ROS levels and upregulated protective antioxidant pathways. Counterintuitively, such elevated oxidative stress and enhanced antioxidant defence mechanisms in cancer cells provide a therapeutic opportunity for the development of drugs with different anticancer mechanisms of action (MoA). In this review, oxidative stress and the role of ROS in cells are described. The tumour-suppressive and tumour-promotive functions of ROS are discussed to compare these two different therapeutic strategies (increasing or decreasing ROS to fight cancer). Clinically approved drugs with demonstrated oxidative stress anticancer MoAs are highlighted before describing examples of metal-based anticancer drug candidates causing oxidative stress in cancer cells via novel MoAs.

Vitamin D Analogs Regulate the Vitamin D System and Cell Viability in Ovarian Cancer Cells

BACKGROUND

Ovarian cancer (OC) is one of the most lethal cancers in women. The active form of vitamin D₃, 1,25-dihydroxyvitamin D₃ (1,25D₃, calcitriol) has anticancer activity in several cancers, including ovarian cancer, but the required pharmacological doses may cause hypercalcemia. We hypothesized that newly developed, low calcemic, vitamin D analogs (an1,25Ds) may be used as anticancer agents instead of calcitriol in ovarian cancer cells.

METHODS

We used two patient-derived high-grade serous ovarian cancer (HGSOC) cell lines with low (13781) and high (14433) mRNA expression levels of the gene encoding 1,25-dihydroxyvitamin D₃ 24-hydroxylase CYP24A1, one of the main target genes of calcitriol. We tested the effect of calcitriol and four structurally related series of an1,25Ds (PRI-1906, PRI-1907, PRI-5201, PRI-5202) on cell number, viability, the expression of CYP24A1, and the vitamin D receptor (VDR).

RESULTS

CYP24A1 mRNA expression increased in a concentration-dependent manner after treatment with all compounds. In both cell lines, after 4 h, PRI-5202 was the most potent analog (in 13781 cells: EC₅₀ = 2.98 ± 1.10 nmol/L, in 14433 cells: EC₅₀ = 0.92 ± 0.20 nmol/L), while PRI-1907 was the least active one (in 13781 cells: EC₅₀ = n/d, in 14433 cells: EC₅₀ = n/d). This difference among the analogs disappeared after 5 days of treatment. The 13781 cells were more sensitive to the an1,25Ds compared with 14433 cells. The an1,25Ds increased nuclear VDR levels and reduced cell viability, but only in the 13781 cell line.

CONCLUSIONS

The an1,25Ds had different potencies in the HGSOC cell lines and their efficacy in increasing CYP24A1 expression was cell line- and chemical structure-dependent. Therefore, choosing sensitive cancer cell lines and further optimization of the analogs' structure might lead to new treatment options against ovarian cancer.

Current Advancements of Plant-Derived Agents for Triple-Negative Breast Cancer Therapy through Deregulating Cancer Cell Functions and Reprogramming Tumor Microenvironment

Triple-negative breast cancer (TNBC) is defined based on the absence of estrogen, progesterone, and human epidermal growth factor receptor 2 receptors. Currently, chemotherapy is the major therapeutic approach for TNBC patients; however, poor prognosis after a standard chemotherapy regimen is still commonplace due to drug resistance. Abnormal tumor metabolism and infiltrated immune or stromal cells in the tumor microenvironment (TME) may orchestrate mammary tumor growth and metastasis or give rise to new subsets of cancer cells resistant to drug treatment. The immunosuppressive mechanisms established in the TME make cancer cell clones invulnerable to immune recognition and killing, and turn immune cells into tumor-supporting cells, hence allowing cancer growth and dissemination. Phytochemicals with the potential to change the tumor metabolism or reprogram the TME may provide opportunities to suppress cancer metastasis and/or overcome chemoresistance. Furthermore, phytochemical intervention that reprograms the TME away from favoring immunoevasion and instead towards immunosurveillance may prevent TNBC metastasis and help improve the efficacy of combination therapies as phyto-adjuvants to combat drug-resistant TNBC. In this review, we summarize current findings on selected bioactive plant-derived natural products in preclinical mouse models and/or clinical trials with focus on their immunomodulatory mechanisms in the TME and their roles in regulating tumor metabolism for TNBC prevention or therapy.

DNA-PK inhibition by M3814 enhances chemosensitivity in non-small cell lung cancer

A significant proportion of non-small cell lung cancer (NSCLC) patients experience accumulating chemotherapy-related adverse events, motivating the design of chemosensitizating strategies. The main cytotoxic damage induced by chemotherapeutic agents is DNA double-strand breaks (DSB). It is thus conceivable that DNA-dependent protein kinase (DNA-PK) inhibitors which attenuate DNA repair would enhance the anti-tumor effect of chemotherapy. The present study aims to systematically evaluate the efficacy and safety of a novel DNA-PK inhibitor M3814 in synergy with chemotherapies on NSCLC. We identified increased expression of DNA-PK in human NSCLC tissues which was associated with poor prognosis. M3814 potentiated the anti-tumor effect of paclitaxel and etoposide in A549, H460 and H1703 NSCLC cell lines. In the four combinations based on two NSCLC xenograft models and two chemotherapy, we also observed tumor regression at tolerated doses in vivo. Moreover, we identified a P53-dependent accelerated senescence response by M3814 following treatment with paclitaxel/etoposide. The present study provides a theoretical basis for the use of M3814 in combination with paclitaxel and etoposide in clinical practice, with hope to aid the optimization of NSCLC treatment.