Corrigendum: Sesquiterpene lactones attenuate paclitaxel resistance via inhibiting MALAT1/STAT3/ FUT4 axis and P-Glycoprotein transporters in lung cancer cells.

[This corrects the article DOI: 10.3389/fphar.2022.795613.].

Elevated 2-oxoglutarate antagonizes DNA damage responses in cholangiocarcinoma chemotherapy through regulating aspartate beta-hydroxylase.

Cholangiocarcinoma (CCA) is resistant to systemic chemotherapies that kill malignant cells mainly through DNA damage responses (DDRs). Recent studies suggest that the involvement of 2-oxoglutarate (2-OG) dependent dioxygenases in DDRs may be associated with chemoresistance in malignancy, but how 2-OG impacts DDRs in CCA chemotherapy remains elusive. We examined serum 2-OG levels in CCA patients before receiving chemotherapy. CCA patients are classified as progressive disease (PD), partial response (PR), and stable disease (SD) after receiving chemotherapy. CCA patients classified as PD showed significantly higher serum 2-OG levels than those defined as SD and PR. Treating CCA cells with 2-OG reduced DDRs. Overexpression of full-length aspartate beta-hydroxylase (ASPH) could mimic the effects of 2-OG on DDRs, suggesting the important role of ASPH in chemoresistance. Indeed, the knockdown of ASPH improved chemotherapy in CCA cells. Targeting ASPH with a specific small molecule inhibitor also enhanced the effects of chemotherapy. Mechanistically, ASPH modulates DDRs by affecting ATM and ATR, two of the major regulators finely controlling DDRs. More importantly, targeting ASPH improved the therapeutic potential of chemotherapy in two preclinical CCA models. Our data suggested the impacts of elevated 2-OG and ASPH on chemoresistance through antagonizing DDRs. Targeting ASPH may enhance DDRs, improving chemotherapy in CCA patients.

Molecular profiling reveals potential targets in cholangiocarcinoma.

BACKGROUND: Cholangiocarcinoma (CCA) is a devastating malignancy and has a very poor prognosis if tumors spread outside the liver. Understanding the molecular mechanisms underlying the CCA progression will likely yield therapeutic approaches toward treating this deadly disease. AIM: To determine the molecular pathogenesis in CCA progression. METHODS: In silico analysis, in vitro cell culture, CCA transgenic animals, histological, and molecular assays were adopted to determine the molecular pathogenesis. RESULTS: The transcriptomic data of human CCA samples were retrieved from The Cancer Genome Atlas (TGCA, CHOL), European Bioinformatics Institute (EBI, GAD00001001076), and Gene Expression Omnibus (GEO, GSE107943) databases. Using Gene set enrichment analysis, the cell cycle and Notch related pathways were demonstrated to be significantly activated in CCA in TCGA and GEO datasets. We, through differentially expressed genes, found several cell cycle and notch associated genes were significantly up-regulated in cancer tissues when compared with the non-cancerous control samples. The associated genes, via quantitative real-time PCR and western blotting assays, were further examined in normal human cholangiocytes, CCA cell lines, mouse normal bile ducts, and mouse CCA tumors established by specifically depleting P53 and expressing KrasG12D mutation in the liver. Consistently, we validated that the cell cycle and Notch pathways are up-regulated in CCA cell lines and mouse CCA tumors. Interestingly, targeting cell cycle and notch pathways using small molecules also exhibited significant beneficial effects in controlling tumor malignancy. More importantly, we demonstrated that several cell cycle and Notch associated genes are significantly associated with poor overall survival and disease-free survival using the Log-Rank test. CONCLUSION: In summary, our study comprehensively analyzed the gene expression pattern of CCA samples using publicly available datasets and identified the cell cycle and Notch pathways are potential therapeutic targets in this deadly disease.

Sesquiterpene Lactones Attenuate Paclitaxel Resistance Via Inhibiting MALAT1/STAT3/ FUT4 Axis and P-Glycoprotein Transporters in Lung Cancer Cells.

Paclitaxel resistance is a challenging factor in chemotherapy resulting in poor prognosis and cancer recurrence. Signal transducer and activator of transcription factor 3 (STAT3), a key transcription factor, performs a critical role in cancer development, cell survival and chemoresistance, while its inactivation overwhelms drug resistance in numerous cancer types including lung cancer. Additionally, the fucosyltransferase 4 (FUT4) is a crucial enzyme in post-translational modification of cell-surface proteins involved in various pathological conditions such as tumor multidrug resistance (MDR). The P-glycoprotein (P-GP) is the well-known ABC transporter member that imparts drug resistance in different cancer types, most notably paclitaxel resistance in lung cancer cells. LncRNA-MALAT1 exerts a functional role in the cancer development as well as the drug resistance and is linked with STAT3 activation and activity of FUT4. Moreover, STAT3-mediated induction of P-GP is well-documented. Natural compounds of Sesquiterpene Lactone (SL) family are well-known for their anticancer properties with particular emphasis over STAT3 inhibitory capabilities. In this study, we explored the positive correlation of MALAT1 with STAT3 and FUT4 activity in paclitaxel resistant A549 (A549/T) lung cancer cells. Additionally, we investigated the anticancer activity of two well-known members of SLs, alantolactone (ALT) and Brevilin A (Brv-A), in A549/T lung cancer cells. ALT and Brv-A induced apoptosis in A549/T cells. Furthermore, these two natural SLs suppressed MALAT1 expression, STAT3 activation, and FUT4 and P-GP expression which are the hallmarks for paclitaxel resistance in A549 lung cancer cells. The inhibition of MALAT1 enhanced the competence of these SLs members significantly, which accounted for the growth inhibition as well as anti-migratory and anti-invasive effects of ALT and Brv-A. These findings suggest SLs to be the promising agents for overcoming paclitaxel resistance in A549 lung cancer cells.

Latcripin-7A from Lentinula edodes C91-3 induces apoptosis, autophagy, and cell cycle arrest at G1 phase in human gastric cancer cells via inhibiting PI3K/Akt/mTOR signaling.

Gastric cancer (G.C) is one of the most lethal cancer types worldwide. Current treatment requires surgery along with chemotherapy, which causes obstacles for speedy recovery. The discovery of novel drugs is needed for better treatment of G.C with minimum side effects. Latcripin-7A (LP-7A) is a newly discovered peptide extracted from Lentinula edodes. It is recently studied for its anti-cancer activity. In this study, LP-7A was modeled using a phyre2 server. Anti-proliferation effects of LP-7A on G.C cells were examined via CCK-8, colony formation, and morphology assay. Apoptosis of LP-7A treated G.C cells was evaluated via Hoechst Stain, western blot and flow cytometry. Autophagy was assessed via acridine orange staining and western blot. The cell cycle was assessed via flow cytometry assay and western blot. Pathway was studied via western blot and STRING database. Anti-migratory effects of LP-7A treated G.C cells were analyzed via wound healing, western blot, and migration and invasion assay. LP-7A effectively inhibited the growth of G.C cells by inhibiting the PI3K/Akt/mTOR pathway. G.C cells treated with LP-7A arrested the cell cycle at the G1 phase, contributing to the inhibition of migration and invasion. Furthermore, LP-7A induced apoptosis and autophagy in gastric cancer cells. These results indicated that LP-7A is a promising anti-cancer agent. It affected the proliferation and growth of G.C cells (SGC-7901 and BGC-823) by inducing apoptosis, autophagy, and inhibiting cell cycle at the G1 phase in G.C cells.

IL-1ß Promotes Vasculogenic Mimicry of Breast Cancer Cells Through p38/MAPK and PI3K/Akt Signaling Pathways.

Vasculogenic mimicry (VM), a micro vessel-like structure formed by the cancer cells, plays a pivotal role in cancer malignancy and progression. Interleukin-1 beta (IL-1ß) is an active pro-inflammatory cytokine and elevated in many tumor types, including breast cancer. However, the effect of IL-1ß on the VM of breast cancer has not been clearly elucidated. In this study, breast cancer cells (MCF-7 and MDA-MB-231) were used to study the effect of IL-1ß on the changes that can promote VM. The evidence for VM stimulated by IL-1ß was acquired by analyzing the expression of VM-associated biomarkers (VE-cadherin, VEGFR-1, MMP-9, MMP-2, c-Fos, and c-Jun) via western blot, immunofluorescent staining, and Immunohistochemistry (IHC). Additionally, morphological evidence was collected via Matrigel-based cord formation assay under normoxic/hypoxic conditions and microvessel examination through Hematoxylin and Eosin staining (H&E). Furthermore, the STRING and Gene Ontology database was also used to analyze the VM-associated interacting molecules stimulated by IL-ß. The results showed that the expression of VM biomarkers was increased in both MCF-7 and MDA-MB-231 cells after IL-1ß treatment. The increase in VM response was observed in IL-1ß treated cells under both normoxia and hypoxia. IL-1ß also increased the activation of transcription factor AP-1 complex (c-Fos/c-Jun). The bioinformatics data indicated that p38/MAPK and PI3K/Akt signaling pathways were involved in the IL-1ß stimulation. It was further confirmed by the downregulated expression of VM biomarkers and reduced formation of the intersections upon the addition of the signaling pathway inhibitors. The study suggests that IL-1ß stimulates the VM and its associated events in breast cancer cells via p38/MAPK and PI3K/Akt signaling pathways. Aiming the VM-associated molecular targets promoted by IL-1ß may offer a novel anti-angiogenic therapeutic strategy to control the aggressiveness of breast cancer cells.

Inhibition of JNK-Mediated Autophagy Promotes Proscillaridin A- Induced Apoptosis via ROS Generation, Intracellular Ca+2 Oscillation and Inhibiting STAT3 Signaling in Breast Cancer Cells.

Breast cancer is the most heterogenous cancer type among women across the world. Despite concerted efforts, breast cancer management is still unsatisfactory. Interplay between apoptosis and autophagy is an imperative factor in categorizing therapeutics for cancer treatment. Proscillaridin A (PSD-A), a well-known cardiac glycoside used for cardiac arrest and arrythmias, has been unveiled in many cancer types but the underlying mechanism for apoptosis and autophagy in breast cancer is not fully understood. In our study, PSD-A restricted cell growth, inhibited STAT3 activation and induced apoptosis and autophagy in breast cancer cells via ROS generation and Ca+2 oscillation. Pretreatment of NAC and BAPTA-AM restored PSD-A induced cellular events in breast cancer cells. PSD-A induced apoptosis via DNA fragmentation, caspase-cascade activation, PARP cleavage, mitochondrial dysfunction, Bax/Bcl-2 proteins modulation and ER chaperone GRP78 inhibition along with decreased phosphorylation of ERK1/2. Inhibition of STAT3 activation was found to be associated with decreased phosphorylation of SRC. Moreover, PSD-A induced events of autophagy i.e. conversion of LC3-I to LC3-II, and Atg3 expression via JNK activation and decreased mTOR and AKT phosphorylation. In this study, pretreatment of SP600125, a JNK inhibitor, reduced autophagy and enhanced STAT3 inhibition and apoptosis. Additionally, SB203580, a commercial p38 inhibitor, stimulated STAT3 activation and improved autophagic events rate in breast cancer cells, displaying the role of the MAPK signaling pathway in interplay between apoptosis and autophagy. Our data suggest that the rate of apoptotic cell death is improved by blocking JNK-induced autophagy in PSD-A treated MCF-7 and MDA-MB-231 breast cancer cells.

Latcripin-7A, derivative of Lentinula edodes C91-3, reduces migration and induces apoptosis, autophagy, and cell cycle arrest at G1 phase in breast cancer cells.

Due to the high mortality rate and an increase in breast cancer incidence, it has been challenging for researchers to come across an effective chemotherapeutic strategy with minimum side effects. Therefore, the need for the development of effective chemotherapeutic drugs is still on the verge. Consequently, we approached a new mechanism to address this issue. The naturally available peptide named latcripin-7A (LP-7A), extracted from a mushroom called Lentinula edodes, provided us promising results in terms of growth arrest, apoptosis, and autophagy in breast cancer cells (MCF-7 and MDA-MB-231). Expressions of protein markers for apoptosis, autophagy, and cell cycle were confirmed via Western blot analysis. Migration and invasion assays were performed to analyze the anti-migratory and anti-invasive properties of LP-7A, while cell cycle analysis was performed via flow cytometry to evaluate its affect over cell growth. Supportive assays were performed like acridine orange, Hoechst 33258 stain, DNA fragmentation, and mitochondrial membrane potential (MMP) to further confirm the anticancer effect of LP-7A on breast cancer cell lines. It is concluded that LP-7A effectively reduces migration and promotes apoptosis as well as autophagy in MCF-7 and MDA-MB-231 breast cancer cell lines by inducing cell growth arrest at G0/G1 phase and decreasing mitochondrial membrane potential without adverse effects on MCF-10A normal breast cells. KEY POINTS: • In this study, we have investigated the anti-cancer activity of novel latcripin-7A (LP-7A), a protein extracted as a result of de novo characterization of Lentinula edodes C91-3. • We conclude in our research work that LP-7A can initiate diverse cell death-related events, i.e., apoptosis and autophagy in both triple-positive and triple-negative breast cancer cell lines by interacting with different nodes of cellular signaling that can further be investigated in vivo to gain a better understanding.

Brevilin A Inhibits STAT3 Signaling and Induces ROS-Dependent Apoptosis, Mitochondrial Stress and Endoplasmic Reticulum Stress in MCF-7 Breast Cancer Cells.

PURPOSE: Breast cancer is the most common malignancy among women across the globe. Despite concerted efforts to improve the prevailing treatment modalities, the overall prognosis of breast cancer remains unsatisfactory. Recently, antiproliferative activity of Brevilin A (Brv-A), a sesquiterpene lactone compound of Centipeda minima, has been unveiled in various cancer types. Here, we have explored anticancer activity of Brv-A in MCF-7 breast carcinoma cells by targeting various pathways. MATERIALS AND METHODS: Cell proliferation rate was determined by CCK-8 and clonogenic assay. Cellular morphological changes were observed under phase contrast microscope while calcein-AM and PI was used for live/dead assay. Cell cycle assay was performed by flow cytometry. Apoptotic cell percentage was determined by Hoechst 33258 staining and flow cytometric analysis. ROS generation and mitochondrial membrane potential were measured using commercially available kits while protein expression was measured by Western blotting. RESULTS: In our study, Brv-A exerted antiproliferative effect through mitotic arrest at G2/M phase of cell cycle and induced apoptosis in MCF-7 cells in a dose-dependent manner. Induction of apoptosis by Brv-A was found to be associated with ROS generation by targeting NOX2 and NOX3, mitochondrial dysfunction (MMP dissipation and Bcl-2 family proteins modulation), DNA fragmentation, JNK and p38 MAPK activation, endoplasmic reticulum (ER) stress by increasing Bip/GRP78, ATF4 and CHOP protein expressions and inhibition of STAT3 activation via decreased phosphorylation of JAK2 and SRC. Pretreatment of NAC, a ROS scavenger, partially reversed the aforesaid cellular events indicating ROS generation as the primary event to modulate cellular targets for induction of apoptosis. Besides, Brv-A has also been documented for inhibition of cell migration via decrease in COX-2 and MMP-2 expression. CONCLUSION: Taken together, Brv-A induces G2/M phase arrest, ROS-dependent apoptosis, ER stress, mitochondrial dysfunction and inhibits STAT3 activation in MCF-7 cells signifying it to be one of the potential anticancer therapeutics in future.

Tunicamycin enhances the suppressive effects of cisplatin on lung cancer growth through PTX3 glycosylation via AKT/NF-κB signaling pathway.

Long pentraxin­3 (PTX3) is an inflammatory molecule related to cancer proliferation, invasion, and metastasis. Many studies have highlighted the significance of glycosylated molecules in immune modulation, inflammation and cancer progression. Moreover, aberrant glycosylation of cancer cells is linked to chemoresistance. This study aimed to develop effective therapeutic strategies for deglycosylation of PTX3 (dePTX3) in order to enhance chemosensitivity to cisplatin (Cis) in lung cancer treatment. The A549 and SPCA1 cells were used to determine the role of PTX3 glycosylation in lung cancer growth. Our results revealed that PTX3 was higher in both human lung cancer tissues and serum in comparison with control. Furthermore, we found that deglycosylated PTX3 (dePTX3) by tunicamycin (TM), which is N­glycan precursor biosynthesis blocker, and PNGase F significantly reduced the survival and migration of lung cancer cells. To further confirm this, we also generated glycosylation­site mutant of PTX3 (mPTX3) to characterize the loss of glyco­function. dePTX3 and TM enhanced the suppressive effects of Cis on lung cancer cell growth, migration and invasion compared to individual treatment. Treatment with a combination of TM and Cis significantly inactivated AKT/NF­κB signaling pathway and induced apoptosis. In conclusion, these findings suggest that PTX3 is an important mediator of lung cancer progression, and dePTX3 by TM enhances the anticancer effects of Cis. The deglycosylation in chemotherapy may represent a potential novel therapeutic strategy against lung cancer.

Microbial fuel cells as an alternative energy source: current status.

Microbial fuel cell (MFC) technology is an emerging area for alternative renewable energy generation and it offers additional opportunities for environmental bioremediation. Recent scientific studies have focused on MFC reactor design as well as reactor operations to increase energy output. The advancement in alternative MFC models and their performance in recent years reflect the interests of scientific community to exploit this technology for wider practical applications and environmental benefit. This is reflected in the diversity of the substrates available for use in MFCs at an economically viable level. This review provides an overview of the commonly used MFC designs and materials along with the basic operating parameters that have been developed in recent years. Still, many limitations and challenges exist for MFC development that needs to be further addressed to make them economically feasible for general use. These include continued improvements in fuel cell design and efficiency as well scale-up with economically practical applications tailored to local needs.