Endoplasmic reticulum stress and IRE-1 signaling cause apoptosis in colon cancer cells in response to andrographolide treatment

Effect of 2,5-hexanedione on rat ovarian granulosa cell apoptosis involves endoplasmic reticulum stress-dependent m-TOR signaling pathway

Occupational exposure to N-hexane/2,5-hexanedione (2,5-HD) was found to adversely affect reproductive functions in females. However, there are few studies regarding the mechanisms underlying reproductive system damage initiated by 2,5-HD. Several studies demonstrated that 2,5-HD exerts hormonal dysfunctions in females by promoting apoptosis using rat ovarian granulosa cells (GCs) as a model. The endoplasmic reticulum (ER) plays a key role in cellular processes such as protein folding and modification, Ca2+ storage, and lipid synthesis, which are known to involve the activation of stress (ERS)-dependent m-TOR signaling pathway. Thus, the aim of this study was to examine the effects of 2,5-HD on ER and the associated activation of stress (ERS)-dependent m-TOR signaling pathway resulting in consequent apoptosis of ovarian GCs. Data demonstrated that after intraperitoneal treatment with 100, 200, or 400 mg/kg 2,5-HD for 6 consecutive weeks, 5 times per week, a decrease in body weight, ovarian weight, and relative ovary weight was found. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay showed that 2,5-HD promoted apoptosis of ovarian GCs, which involved enhanced relative protein expression levels of m-TOR/p-mTOR. Our findings demonstrated that 2,5-HD (1) elevated expression levels of pro-apoptosis-related genes Bax and Caspase 3, (2) decreased expression levels of the anti-apoptosis gene Bcl-2, and (3) activated the protein expression of glucose-regulatory protein 78 (GRP78), inositol-requiring enzyme-1 (IRE1), and c-Jun terminal kinase (JNK) associated with increased apoptosis. Evidence indicates that chronic exposure to 2,5-HD induced apoptosis of ovarian GCs, and the possible mechanism underlying this effect involves the ERS-dependent m-TOR signaling pathway.

Targeting mitochondrial ribosomal protein expression by andrographolide and melatonin for colon cancer treatment

Colospheroids contain colon cancer stem cells (CSCs) that cause colorectal cancer metastasis (mCRC). Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the U.S. Little is known about the role of mitochondria in the survival and metastatic ability of CSCs. In this study, we investigate the effect of andrographolide (AGP) and melatonin (MLT) on mitochondrial dynamics (including fusion and fission) and the expression of mitochondrial ribosomal proteins (MRPs). Our results show that AGP and MLT synergistically reduce the total active mitochondrial mass, downregulate fusion and fission proteins, reduce OXPHOS proteins, and lead to CSC growth inhibition via Nrf2 and KEAP1 signaling. Microarray revealed 4389 differentially expressed mRNAs in the AGP and MLT combination compared to the control. Results exhibiting a three-fold induction/reduction were validated by qRT-PCR and immunoblot. MRPS6, a mitochondrial ribosomal (Mitoribosome) small subunit protein, was dramatically downregulated by AGP + MLT treatment compared to control. MRPS6 inhibition by siRNA reduced mCRC cell viability. Molecular docking-based protein-ligand interactions showed that AGP has direct physical interaction with MRPS6 and increases the binding affinity of MLT to MRPS6. This drug combination downregulated genes in the NRF2 (NFE2L2) pathway in CSCs. MRPS6 may be directly linked to CSC proliferation and could be a therapeutic target for this population. Functionally, MRPS6 knockdown significantly reduced colony formation, with enhanced suppression in AGP + MLT-treated cells. In xenograft models, the AGP-MLT combination synergistically decreased MRPS6 expression and increased apoptosis, as evidenced by TUNEL assays, demonstrating the therapeutic potential of targeting MRPS6 in CRC.

Exploring the molecular interactions between ferroptosis and the Wnt/β-catenin signaling pathway: Implications for cancer and disease therapy

Ferroptosis, a regulated form of cell death dependent on iron and marked by lipid peroxidation, is increasingly recognized for its role in a wide array of diseases, including cancers, neurodegenerative disorders, and tissue damage. This review examines the dynamic interaction between ferroptosis and the Wnt/β-catenin signaling pathway, focusing on how Wnt surface receptors, ligands, antagonists, and associated components influence the regulation of ferroptosis. Key elements such as Frizzled receptors, Wnt ligands, and antagonists like DKK1 are shown to affect ferroptosis by altering oxidative stress, lipid dynamics, and iron metabolism. A central aspect of this interaction is the role of the destruction complex, particularly GSK-3β, which regulates ferroptosis through its upstream modulation by the AKT pathway and downstream control over NRF2, GPX4, and SLC7A11. Furthermore, the involvement of β-catenin/TCF transcription factors in the regulation of ferroptosis emphasizes the significance of this pathway in promoting cell survival and resisting ferroptosis, particularly in various cancers. Multiple cancers, including colorectal, breast, ovarian, and lung cancers, are affected by disruptions in the Wnt/ferroptosis axis, where enhanced Wnt signaling helps cancer cells evade ferroptosis and develop resistance to treatments. Beyond cancer, this axis also plays a crucial role in neurodegenerative diseases and conditions like myocardial infarction. Additionally, natural compounds have shown potential in modulating the Wnt/ferroptosis pathway, offering promising therapeutic approaches for a variety of diseases. This review highlights the molecular mechanisms of the Wnt/ferroptosis axis, paving the way for innovative treatment options in cancer and other diseases.

Regulatory function of endoplasmic reticulum stress in colorectal cancer: Mechanism, facts, and perspectives

Colorectal cancer (CRC) is an exceedingly common and profoundly impactful malignancy of the digestive system, posing a grave threat to human health. Endoplasmic reticulum stress (ERS) is an intracellular biological reaction that mobilizes the unfolded protein response (UPR) to tackling dysregulation in protein homeostasis. This process subtly modulates the cell to either restore normal cellular function or steer it towards apoptosis. The high metabolic demands of CRC cells sculpt a rigorous tumor microenvironment (TME), compelling CRC cells to experience ERS. Adaptive responses induced by mild ERS furnish the necessary conditions for the survival of CRC cells, whereas the cell death mechanisms triggered by sustained ERS could be considered a prospective strategy for cancer therapy. Considering the complex regulation of ERS in cancer development, this article offers a comprehensive review of the molecular mechanisms through which ERS influences CRC fate. It provides crucial insights for exploring the role of ERS in the occurrence and progression of CRC, laying a new theoretical foundation for devising precise therapeutic strategies targeting ERS. Furthermore, by synthesizing extensive clinical and preclinical studies, we delve into therapeutic strategies targeting ERS, including the potential of targeting ERS in immunotherapy, the utilization of native compounds, advancements in proteasome inhibitors, and the potential synergies of these strategies with traditional chemotherapy agents and emerging therapeutic approaches.

Asiatic acid improves the damage of HaCaT cells induced by nitrogen mustard through inhibiting endoplasmic reticulum stress

Nitrogen mustard (NM) belongs to vesicant agents. Blisters are one of the important characteristics of NM skin damage. It is urgent to further elucidate the mechanism and develop effective countermeasures for the skin damage induced by NM. The endoplasmic reticulum (ER) is an important intracellular organelle, playing an important role in maintaining cellular homeostasis. In this study, we explored the role of endoplasmic reticulum stress (ERS) and the protective effect of asiatic acid (AA) in the HaCaT cells induced by NM. It was found that the key regulatory proteins of ERS, such as glucose regulated protein 78 (GRP78), X-box binding protein 1 (XBP1), inositol requiring enzyme 1 (IRE1), Phospho-IRE1 (pIRE1), and TNF receptor associated factor 2 (TRAF2) were increased respectively in HaCaT cells exposed to NM compared with those of the control group, showing an increasing trend with the increase of NM exposure concentration and exposure time. Additionally, the protein expression of Caspase-3 and the Cleaved-Caspase-3 was also increased by NM in HaCaT cells, resulting in the apoptosis of HaCaT cells. Meanwhile, the content of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) was also increased in HaCaT cells exposed to NM. Further study showed that AA pretreatment could decrease the protein expression of GRP78, XBP1 and IRE1, pIRE1, TRAF2, Caspase-3, and Cleaved-Caspase-3. And moreover, AA also could reduce the content of TNF-α and IL-6. Overall, the present study showed that AA played an important protective effect in HaCaT cells exposed to NM through the inhibition of the ERS-induced apoptosis and inflammatory response.

GRP78: A new promising candidate in colorectal cancer pathogenesis and therapy

Colorectal cancer (CRC) is a significant global health challenge, marked by varying incidence and mortality rates across different regions. The pathogenesis of CRC involves multiple stages, including initiation, promotion, progression, and metastasis, influenced by genetic and epigenetic factors. The chaperone protein glucose-regulated protein 78 (GRP78), crucial in regulating the unfolded protein response (UPR) during endoplasmic reticulum (ER) stress, plays a pivotal role in CRC pathogenesis. This review discusses the expression profile of GRP78 in CRC, highlighting its potential as a prognostic biomarker and its role in modulating the cellular mechanisms of CRC, including ER response regulation, cell proliferation, migration and invasion. The complex molecular interactions of GRP78 with key signaling pathways such as protein kinase B (Akt), Wnt, protein kinase R-like ER kinase (PERK), vascular endothelial growth factor (VEGF), and Kirsten rat sarcoma virus (Kras) are explored, elucidating its contributions to tumor survival, proliferation, invasion, and chemoresistance. GRP78's involvement in autophagy, glycolysis, and immune regulation further underscores its importance in CRC progression. The review also covers the therapeutic potential of targeting GRP78 in CRC, examining various natural products like curcumin, epigallocatechin gallate (EGCG), and aloe-emodin, which modulate GRP78 expression and activity. Additionally, GRP78's role in mediating resistance to chemotherapeutic agents like 5-fluorouracil (5-FU) and oxaliplatin is discussed, emphasizing its significance in the development of resistance mechanisms in CRC. In conclusion, GRP78 emerges as a central player in CRC pathogenesis and a promising target for therapeutic interventions aimed at improving treatment outcomes and overcoming chemoresistance in colorectal cancer.

An Innovative Method of Improving an Extract of Andrographis paniculata from Leaves: Its Anticancer Effect Involves the Cell Endoplasmic Reticulum

In this manuscript, the effects of two extracts from Andrographis paniculata were tested: (a) an extract titrated to 49.7% of andrographolide and obtained from leaves of the plant: (b) the pure andrographolide titrated to 99%. The extracts were dissolved in 1-butanol and tested on tumor lines (MCF7 and SH-SY5Y) and the non-tumor line (Huvec) to understand the effects on cell proliferation. The addition of a sonication process improved their dissolution and efficacy making these extracts unique and innovative. The experiments conducted (viability measurements, solubility of the extracts, IC50 tests, measurement of oxidative potential, lipid and cytosolic calcium concentration, and mortality assessment by annexin assay) showed a different behavior of the extracts on cancer cells and not. In particular, the extracts did not cause toxic effects on the viability of the Huvec cells, while both tumor lines were damaged, demonstrating that cancer cells are more susceptible to extracts of A. paniculata than healthy cells. The mechanism of action responsible for the damage detected involved the functioning of the endoplasmic reticulum organelle and finally resulted in apoptotic death. For this reason, the extracts considered have shown a potential anti-tumor role and A. paniculata could be used and exploited in pharmacological therapy against cancer. However, further studies, obtained in clinical practice, should be conducted to increase knowledge of the effects of A. paniculata on the organism and its phytotherapeutic role.

Comprehensive Insights Into the Combinatorial Uses of Selected Phytochemicals in Colorectal Cancer Prevention and Treatment: Isothiocyanates, Quinones, Carotenoids, and Alkaloids

Despite the advancement in cancer diagnosis and treatment, colorectal cancer remains the leading cause of cancer-related death worldwide. Given the high recurrence rate of colorectal cancer even after surgical resection, chemotherapy has been clinically used to improve the treatment outcomes of colorectal cancer. However, chemotherapy is well-known for its toxic side effects. Thus, phytochemicals have been widely studied in recent years as preventive and therapeutic agents for colorectal cancer owing to their relatively low toxicity. Moreover, combinatorial uses of phytochemicals with other natural compounds or with drugs may amplify the positive outcomes of colorectal cancer prevention and treatment by intervening in multiple signaling pathways and targets. This review summarized the combinatorial use of several well-studied groups of phytochemicals, that is, isothiocyanates, quinones, carotenoids, and alkaloids, in the prevention and treatment of colorectal cancer, and suggested it as a potential approach to improve the anticancer efficacy of single compounds and minimize the toxic side effects associated with conventional drugs. Notably, we generalized the in vitro, in vivo, and clinical experiments-based molecular mechanisms whereby the selected phytochemicals in combination with other compounds exerted anti-colorectal cancer effects by inhibiting cancer cell proliferation, cell apoptosis, cell invasion, and tumor growth. Overall, this review provides a reference and new perspective to propel further advancements in research and development of preventative and therapeutic strategies for colorectal cancer.

Revisiting Luteolin Against the Mediators of Human Metastatic Colorectal Carcinoma: A Biomolecular Approach

Metastatic colorectal carcinoma (mCRC) is one of the prevalent subtypes of human cancers and is caused by the alterations of various lifestyle and diet-associated factors. β-catenin, GSK-3β, PI3K-α, AKT1, and NF-κB p50 are known to be the critical regulators of tumorigenesis and immunopathogenesis of mCRC. Unfortunately, current drugs have limited efficacy, side effects and can lead to chemoresistance. Therefore, searching for a nontoxic, efficacious anti-mCRC agent is crucial and of utmost interest. The present study demonstrates the identification of a productive and nontoxic anti-mCRC agent through a five-targets (β-catenin, GSK-3β, PI3K-α, AKT1, and p50)-based and three-tier (binding affinity, pharmacokinetics, and pharmacophore) screening strategy involving a series of 30 phytocompounds having a background of anti-inflammatory/anti-mCRC efficacy alongside 5-fluorouracil (FU), a reference drug. Luteolin (a phyto-flavonoid) was eventually rendered as the most potent and safe phytocompound. This inference was verified through three rounds of validation. Firstly, luteolin was found to be effective against the different mCRC cell lines (HCT-15, HCT-116, DLD-1, and HT-29) without hampering the viability of non-tumorigenic ones (RWPE-1). Secondly, luteolin was found to curtail the clonogenicity of CRC cells, and finally, it also disrupted the formation of colospheroids, a characteristic of metastasis. While studying the mechanistic insights, luteolin was found to inhibit β-catenin activity (a key regulator of mCRC) through direct physical interactions, promoting its degradation by activating GSK3-β and ceasing its activation by inactivating AKT1 and PI3K-α. Luteolin also inhibited p50 activity, which could be useful in mitigating mCRC-associated proinflammatory milieu. In conclusion, our study provides evidence on the efficacy of luteolin against the critical key regulators of immunopathogenesis of mCRC and recommends further studies in animal models to determine the effectiveness efficacy of this natural compound for treating mCRC in the future.

The therapeutic potential of andrographolide in cancer treatment

Cancer poses a substantial global health challenge, necessitating the widespread use of chemotherapy and radiotherapy. Despite these efforts, issues like resistance development and severe side effects remain. As such, the search for more effective alternatives is critical. Andrographolide, a naturally occurring compound, has recently gained attention for its extensive biological activities. This review explores the role of andrographolide in cancer therapy, especially focusing on the molecular mechanisms that drive its anti-tumor properties. It also examines innovative methods to enhance andrographolide's bioavailability, thus boosting its effectiveness against cancer. Notably, andrographolide has potential for use in combination with various clinical drugs, and both preclinical and clinical studies provide strong evidence supporting its broader anticancer applications. Additionally, this paper proposes future research directions for andrographolide's anti-cancer effects and discusses the challenges in its clinical usage along with current research efforts to address these issues. In summary, this review underscores andrographolide's potential roles and contributes to the development of improved cancer treatment strategies.

Sustained high expression of NRF2 inhibits cell apoptosis in arsenite-transformed human keratinocytes

Our previous study identified that nuclear factor-erythroid-2 p45-related factor 2 (NRF2) was activated in arsenite-induced tumorigenesis. However, the underlying mechanisms of NRF2 mediating apoptosis in arsenic-induced skin carcinogenesis remain unknown. This study explored the dynamic changes in apoptosis rate and the expression of apoptosis proteins in immortalized human keratinocytes (HaCaT) malignant transformation caused by 1.0 μM NaAsO2 at passages 0, 1, 7, 14, 21, 28, and 35. The result showed that the apoptosis rate decreased. The apoptosis-related proteins cleaved-caspase-3/caspase-3 ratio decreased in the later stages (passages 21, 28, and 35). Moreover, the expression of intrinsic ER stress pathway-related CHOP, ATF4, ATF6, and the intrinsic mitochondrial pathway-related Bax protein decreased in the later stages, while Bcl-2 and Mcl-1 increased, and NRF2 protein levels also increased. The apoptosis rate increased by silencing NRF2 expression in arsenite-transformed HaCaT (T-HaCaT) cells. Meanwhile, the expression of pro-apoptotic proteins (cleaved-caspase-3/caspase-3, CHOP, Bax) and ATF4, ATF6 increased. On the contrary, antiapoptotic protein levels (Bcl-2 and Mcl-1) decreased. The ability of colony formation and migration of T-HaCaT cells decreased. In conclusion, arsenite activated NRF2 in the later stages, decreasing apoptosis characterized by inhibiting endoplasmic reticulum stress-depended and mitochondria-depended apoptosis pathway, and further promoting NaAsO2-induced HaCaT cellular malignant transformation.

The preventive effects of natural plant compound carvacrol against combined UVA and UVB-induced endoplasmic reticulum stress in skin damage of rats

The skin is constantly exposed to a variety of environmental stressors, including ultraviolet (UV) radiation. Exposure of the skin to UV radiation causes a number of detrimental biological damages such as endoplasmic reticulum (ER) stress. The ER stress response is a cytoprotective mechanism that maintains homeostasis of the ER by increasing the capacity of the ER against the accumulation of unfolded proteins in the ER. Carvacrol (CRV) is a monoterpenoid phenol found in essential oils with antimicrobial and anti-inflammatory activities. We investigated for the first time in the literature the potential protective role of CRV against combined UVA and UVB-induced skin damage by targeting the ER stress pathway in a rat model. For this purpose, expressions of Grp78, Perk, Atf6, Ire-1, Chop, Xbp1, Casp12, elF2α, and Traf2 genes related to ER stress were analyzed by RT-PCR and protein expression levels of GRP78, ATF6, CHOP, and XBP1 were determined by ELISA assay in tissue sections taken from the back of the rats. As a result of analysis, it was seen that the expression levels of aforementioned ER stress genes increased significantly in the UVA + UVB irradiated group compared to the control group, while their expression levels decreased markedly by supplementation of CRV in UVA + UVB + CRV group. With regard to expressions of foregoing proteins, their levels escalated notably with UVA + UVB application and decreased markedly by CRV supplementation. In conclusion, present study revealed that CRV ameliorates UVA + UVB-induced ER stress via reducing the expression of mRNA as well as proteins involved in the unfolded protein response (UPR) pathway and inducing apoptosis as evidenced from high Caspase12 level.

Possible role of endoplasmic reticulum stress in the pathogenesis of chronic adenoiditis and adenoid hypertrophy: A prospective, parallel-group study

Background

Adenoid tissue is a first-line host defense secondary lymphoid organ, especially in childhood. The endoplasmic reticulum (ER) is required to maintain balanced cellular activity. With impaired ER functions, protein accumulation occurs, resulting in ER stress, which plays a role in the etiopathogenesis of many diseases.

Objective

We aimed to investigate the relationship between ER stress and adenoid tissue disorders, thereby elucidating the mechanisms of immunity-related diseases.

Methods

Fifty-four pediatric patients (>3 years old) who underwent adenoidectomy for chronic adenoiditis (CA) or adenoid hypertrophy (AH) were enrolled in this prospective, parallel-group clinical study. Adenoids were divided into two groups (CA or AH) based on their size and evaluated for ER stress pathway and apoptosis pathway markers by Real-time PCR and Western blot analysis.

Results

ER stress pathway markers significantly differed between the CA and AH groups. Children with CA had higher ER stress marker levels than the AH group (p < .001 for ATF-4, ATF-6, and GRP78, and p < .05 for EDEM1, CHOP, EIF2AK3, ERNI, and GRP94). Apoptosis pathway marker levels (BAX and BCL-2) were not different between groups.

Conclusions

ER stress contributes to the etiopathogenesis of adenoid tissue diseases and the pathogenesis of adenoid tissue disorders, which are part of the immune response. These results may guide the development of new and alternative treatments for immune system disorders.

Cytotoxic Effect of Andrographis paniculata Associated with 2-Aminoethyl Dihydrogen Phosphate in Triple-Negative Breast Cells

Cancer stands out as a major global public health concern and a significant impediment to increasing life expectancy worldwide. Natural bioactives derived from plants are renowned for their efficacy in treating various types of cancer. Andrographis paniculata (Burm.f.) is a well-known plant traditionally employed in diverse medical systems across the globe. The 2-AEH2P monophosphoester, a molecule intricately involved in phospholipid turnover, demonstrates antiproliferative effects across a broad spectrum of cancer types. This study aims to assess the antitumor, antiproliferative, and pharmacological effects of andrographolide at different concentrations, both individually and in conjunction with 2-aminoethyl dihydrogen phosphate. The cytotoxicity of the treatments was evaluated using the colorimetric MTT method, cell cycle phases, mitochondrial electrical potential, and markers expression via flow cytometry, while the pharmacological effects were assessed using SynergyFinder software 3.0. Treatments with A. paniculata, isolated at concentrations of 10%, 30%, and 50% of andrographolide, induced cell death in tumor cells, resulting in a reduction in mitochondrial electrical potential and alterations in cell cycle phases, particularly a decrease in the population of MDA MB-231 cells in the G0/G1 phase. The combination treatments exhibited significant cytotoxicity toward tumor cells, with minimal toxicity observed in normal fibroblast cells FN1. This led to a reduction in mitochondrial electrical potential and cell cycle arrest in the S phase for MDA MB-231 cells. Across all concentrations, the combined treatments demonstrated a synergistic pharmacological effect, underscoring the efficacy of the association. There was a change in the markers involved in cell death, such as p53, caspase 3, Bcl-2, and cytochrome c, suggesting the induction of regulated cell death. Markers associated with progression and proliferation, such as cyclin D1 and p21, corroborate the findings for cytotoxicity and cell cycle arrest.

Differential Signaling Pathways in Medulloblastoma: Nano-biomedicine Targeting Non-coding Epigenetics to Improve Current and Future Therapeutics

BACKGROUND

Medulloblastomas (MDB) are malignant, aggressive brain tumors that primarily affect children. The survival rate for children under 14 is approximately 72%, while for ages 15 to 39, it is around 78%. A growing body of evidence suggests that dysregulation of signaling mechanisms and noncoding RNA epigenetics play a pivotal role in this disease.

METHODOLOGY

This study conducted an electronic search of articles on websites like PubMed and Google. The current review also used an in silico databases search and bioinformatics analysis and an extensive comprehensive literature search for original research articles and review articles as well as retrieval of current and future medications in clinical trials.

RESULTS

This study indicates that several signaling pathways, such as sonic hedgehog, WNT/β-catenin, unfolded protein response mediated ER stress, notch, neurotrophins and TGF-β and ERK, MAPK, and ERK play a crucial role in the pathogenesis of MDB. Gene and ncRNA/protein are also involved as an axis long ncRNA to sponge micro-RNAs that affect downstream signal proteins expression and translation affection disease pathophysiology, prognosis and present potential target hit for drug repurposing. Current treatment options include surgery, radiation, and chemotherapy; unfortunately, the disease often relapses, and the survival rate is less than 5%. Therefore, there is a need to develop more effective treatments to combat recurrence and improve survival rates.

CONCLUSION

This review describes various MDB disease hallmarks, including the signaling mechanisms involved in pathophysiology, related-causal genes, epigenetics, downstream genes/epigenes, and possibly the causal disease genes/non-protein coding (nc)RNA/protein axis. Additionally, the challenges associated with MDB treatment are discussed, along with how they are being addressed using nano-technology and nano-biomedicine, with a listing of possible treatment options and future potential treatment modalities.

Anticancer effect of polyphenolic acid enriched fractions from Grewia bracteata Roth on tumor cells and their p53 gene independent ROS mediated apoptosis in colon cancer cells

It is the first report on leaves of Grewia bracteata Roth for its anticancer effect. In this study, three polarity-guided solvent extracts of Grewia bracteata leaves from n-hexane (GLH), ethyl acetate (GLE), and methanol (GLM) were screened for anticancer effects on HeLa, HCT-116, MCF-7, HCT-116 p53-/- and PC-3 cells via methyl thiazoldiphenyltetrazolium bromide (MTT) assay. Based on the results, GLM was fractionated, and the obtained fractions were tested on HCT-116 cells. Further, FT-IR, HPLC analysis, clonogenic assay, wound healing assay, DCFDA, and cell cycle experiments were conducted on HCT-116 cells. The extracts from methanol (GLM) and ethyl-acetate (GLE) demonstrated a more selective and promising inhibition on HCT-116 cells than others. Notably, GLM recorded superior inhibition on HCT-116 p53-/- than GLE. Amongst, the methanol column fraction (GMCF) showed prominent inhibition on HCT-116 (IC50:63.55 ± 0.61 μg/ml) and HCT-116 p53-/- (IC50: 84.51 ± 0.58 μg/ml) cells. Further, the test on normal cells (NKE) revealed minimal toxicity of GMCF. The phytochemical test, FT-IR, HPLC, and LC-HRMS analyses confirmed the high abundance of polyphenolic acid/polyphenols in GMCF. Further, the clonogenic and wound healing assays on HCT-116 cells were also performed. Later, the probable cell death mechanism was identified using DCFDA and cell cycle experiments. These experiments disclosed that GMCF induced HCT-116 cell death was probably due to reactive oxygen species (ROS) upregulation and cells cycle arrest at SubG0 phase. It inferred that the activity is most probably p53 independent, a tumor suppressor gene responsible for drug resistance in colon cancer.

Activation of hypermethylated P2RY1 mitigates gastric cancer by promoting apoptosis and inhibiting proliferation

The P2RY1 receptor is known to cause cancer by activating the ERK signal pathway, and its DNA methylation status and corresponding regulatory mechanism remain unknown. This study used the DNA methylation chip to profile the genome-wide DNA methylation level in gastric cancer tissues. The proliferation and apoptosis of the SGC7901 gastric cancer cell line were determined after treatment with a selective P2RY1 receptor agonist, MRS2365. The promoter region of P2RY1 was found to be highly methylated with four hypermethylated sites (|Δβ value| > 0.2) in diffuse gastric cancer and was validated by bioinformatics analysis in the TCGA database. Also, immunohistochemical staining data obtained from the HPA database demonstrated the downregulated expression of proteins encoded by P2RY1 in stomach cancer tissue. The analysis of MRS2365-treated cells by annexin V/propidium iodide staining and caspase-3 activity assays indicated the induction of apoptosis in SGC7901 cells. The P2RY1 receptor activation in human SGC7901 gastric cancer cells via the MRS2365 agonist induced apoptosis and reduced cell growth. High DNA methylation in the promoter region of P2RY1 might have contributed to the reduced expression of P2RY1's mRNA, which was likely responsible for the "aggressive" nature of the diffuse gastric cancer.

Research progress of treatment of functional dyspepsia with traditional Chinese medicine compound based on cell signal pathway

Functional dyspepsia (FD) is the most common clinical gastrointestinal disease, with complex and prolonged clinical symptoms. The prevalence of FD is increasing year by year, seriously affecting the quality of life of patients. The main causes of FD are related to abnormal gastrointestinal dynamics, increased visceral sensitivity, Helicobacter pylori (HP) infection, intestinal flora disturbance and psychological factors. A review of the relevant literature reveals that the mechanisms of traditional Chinese medicine (TCM) in the treatment of FD mainly involve the following pathways:5-HT signal pathway, AMPK signal pathway,C-kit signal pathway, CRF signal pathway, PERK signal pathway,NF-κB signal pathway. Based on a holistic concept, TCM promotes gastrointestinal motility, regulates visceral sensitivity and alleviates gastrointestinal inflammation through multiple signal pathways, reflecting the advantages of multi-level, multi-pathway and multi-targeted treatment of FD.

Endoplasmic Reticulum Stress in Elderly Patients with COVID-19: Potential of Melatonin Treatment

Aging processes, including immunosenescence, inflammation, inflammasome formation, genomic instability, telomeric attrition, and altered autophagy, are involved in viral infections and they may contribute to increased pathophysiological responses to the SARS-CoV-2 infection in the elderly; this poses additional risks of accelerated aging, which could be found even after recovery. Aging is associated with oxidative damage. Moreover, SARS-CoV-2 infections may increase the production of reactive oxygen species and such infections will disturb the Ca++ balance via an endoplasmic reticulum (ER) stress-mediated unfolded protein response. Although vaccine development and anti-inflammation therapy lower the severity of COVID-19, the prevalence and mortality rates are still alarming in some countries worldwide. In this review, we describe the involvement of viral proteins in activating ER stress transducers and their downstream signals and in inducing inflammation and inflammasome formation. Furthermore, we propose the potential of melatonin as an ER stress modulator, owing to its antioxidant, anti-inflammatory, and immunoregulatory effects in viral infections. Considering its strong safety profile, we suggest that additive melatonin supplementation in the elderly could be beneficial in treating COVID-19.

System analysis based on the ER stress-related genes identifies WFS1 as a novel therapy target for colon cancer

BACKGROUND

Colon cancer (COAD) is the third-largest common malignant tumor and the fourth major cause of cancer death in the world. Endoplasmic reticulum (ER) stress has a great influence on cell growth, migration, proliferation, invasion, angiogenesis, and chemoresistance of massive tumors. Although ER stress is known to play an important role in various types of cancer, the prognostic model based on ER stress-related genes (ERSRGs) in colon cancer has not been constructed yet. In this study, we established an ERSRGs prognostic risk model to assess the survival of COAD patients.

METHODS

The COAD gene expression profile and clinical information data of the training set were obtained from the GEO database (GSE40967) and the test set COAD gene expression profile and clinical informative data were downloaded from the TCGA database. The endoplasmic reticulum stress-related genes (ERSRGs) were obtained from Gene Set Enrichment Analysis (GSEA) website. Differentially expressed ERSRGs between normal samples and COAD samples were identified by R "limma" package. Based on the univariate, lasso, and multivariate Cox regression analysis, we developed an ERSRGs prognostic risk model to predict survival in COAD patients. Finally, we verified the function of WFS1 in COAD through in vitro experiments.

RESULTS

We built a 9-gene prognostic risk model based on the univariate, lasso, and multivariate Cox regression analysis. Kaplan-Meier survival analysis and Receiver operating characteristic (ROC) curve revealed that the prognostic risk model has good predictive performance. Subsequently, we screened 60 compounds with significant differences in the estimated half-maximal inhibitory concentration (IC50) between high-risk and low-risk groups. In addition, we found that the ERSRGs prognostic risk model was related to immune cell infiltration and the expression of immune checkpoint molecules. Finally, we determined that knockdown of the expression of WFS1 inhibits the proliferation of colon cancer cells.

CONCLUSIONS

The prognostic risk model we built may help clinicians accurately predict the survival of patients with COAD. Our findings provide valuable insights into the role of ERSRGs in COAD and may provide new targets for COAD therapy.

Andrographolide elevates tumor necrosis factor-related apoptosis-inducing ligand lethality through reactive oxygen species accumulation and gasdermin E cleavage in breast cancer cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is selectively lethal to cancer cells and harmless to normal cells, making it a potential agent for cancer therapy. However, some breast cancer cells are resistant to TRAIL. This study revealed that andrographolide (Andro), an extract from Andrographis paniculate, a natural compound, sensitized breast cancer cells to TRAIL-induced tumor suppression; it identified apoptosis-associated protein regulation, reactive oxygen species accumulation, mitochondria membrane potential disruption, caspase cascade activation, and gasdermin-E cleavage to be involved in the tumor lethality mediated by Andro combined with TRAIL treatment. The flow cytometry results showed the combination of Andro and TRAIL repressed breast cancer cells by cell death induction, and the assessment of combined index indicated that the combined treatment with Andro and TRAIL repressed breast cancer cells synergistically. Blotting results displayed Andro and TRAIL combination elevated TRAIL-associated receptors, death receptors 4 and 5, at protein levels. These results provided critical insight into breast cancer patients' therapy and exploration direction for TRAIL clinical application.

Melatonin and andrographolide synergize to inhibit the colospheroid phenotype by targeting Wnt/beta-catenin signaling

β-catenin signaling, and angiogenesis are associated with colospheroid (CSC), development. CSCs, spheroids derived from colon cancer cells, are responsible for metastasis, drug resistance, and disease recurrence. Whether dysregulating β-catenin and inhibiting angiogenesis reduce CSC growth is unknown. In this study, the molecular mechanism of CSC growth inhibition was evaluated using a novel combination of melatonin (MLT) and andrographolide (AGP). These drugs have anticarcinogenic, antioxidant, and antimetastatic properties. CSCs were obtained from two metastatic colon cancer cell lines (HT29 and HCT-15). The viability and stemness were monitored (FDA propidium iodide staining and immunoblot for CD44, CD133, Nanog, Sox2, and Oct4). The drug combination synergistically diminished stemness via increased reactive oxygen species (ROS) levels, reduced mitochondrial membrane potential and ATP level. MLT + AGP induced cell death by inhibiting β-catenin expression and its downregulatory signals, Cyclin D1, c-Myc. MLT + AGP treated cells exhibited translocation of phospho-β-catenin to the nucleus and dephosphorylated-β-catenin. Downregulation of β-catenin activation and its transcription factors (TCF4 and LEF1) and GTP binding/G-protein related activity were found in the dual therapy. Angiogenic inhibition is consistent with downregulation of VEGF messenger RNA transcripts (VEGF189), phosphorylated VEGF receptor protein expression, matrigel invasion, and capillary tube inhibition. In vivo, the intravenous injection of MLT + AGP slowed HT29 metastatic colon cancer. Histopathology indicated significant reduction in microvascular density and tumor index. Immunohistochemistry for caspase 7, and β-catenin found increased apoptosis and downregulation of β-catenin signals. The mechanism(s) of decreased colospheroids growth were the inhibition of the Wnt/β-catenin pathway. Our results provide a rationale for using MLT in combination with AGP for the inhibition of CRCs.

Triazole fungicide tebuconazole induces apoptosis through ROS-mediated endoplasmic reticulum stress pathway

Tebuconazole (TEB) is a common triazole fungicide that has been widely applied in the treatment of fungal diseases. It is reported that TEB could exert harmful effects on mammals' health. However, the molecular mechanism involved in TEB toxicity remain undefined. Our study aimed to investigate the mechanisms of TEB-induced toxicity in intestinal cells. We found that TEB stimulates apoptosis through the mitochondrial pathway. Additionally, TEB triggers endoplasmic reticulum (ER) stress as demonstrated by the activation of the three arms of unfolded protein response (UPR). The incubation with the chemical chaperone 4-phenylbutyrate (4-PBA) alleviated ER stress and reduced TEB-induced apoptosis, suggesting that ER stress plays an important role in mediating TEB-induced toxicity. Furthermore, inhibition of ROS by N-acetylcysteine (NAC) inhibited TEB-induced ER stress and apoptosis. Taken together, these findings suggest that TEB exerts its toxic effects in HCT116 cells by inducing apoptosis through ROS-mediated ER stress and mitochondrial apoptotic pathway.

An insight into the pharmacological and analytical potential of Andrographolide

Andrographis paniculata is an annual medicinal herb from the family Acanthaceae. Andrographolide is generally considered an essential bioactive component of plant A. paniculata. Since ancient times, it has been widely recognized for its therapeutic qualities and has attracted the scientific and medical communities' attention. This review summarizes the molecular, clinical, and in vitro research of compound andrographolide and its mechanism of action. Andrographolide, when combined with other enhancing agents, offers a wide variety of health benefits. The therapeutic potential of andrographolide has been exemplified and exhibited by directly regulating genes and indirectly interacting with small molecules and different enzymes. This review compiles and consolidates the pharmacological action of andrographolide and its analogs and deciphers the gaps that have hindered its use in medicinal research.

Recombinant human growth hormone improves the immune status of rats with septic encephalopathy: The role of VEGFR2 in the prevalence of endoplasmic reticulum stress repair module

Septic encephalopathy results from the intense reaction of the immune system to infection. The role of growth hormone (GH) signaling in maintaining brain function is well established; however, the involvement of the vascular endothelial growth factor receptor-2 (VEGFR2) in the potential modulatory effect of GH on septic encephalopathy-associated endoplasmic reticulum stress (ERS) and blood-brain barrier (BBB) permeability is not well-understood. Therefore, after the induction of mid-grade sepsis by cecal ligation/perforation, rats were subcutaneously injected with recombinant human GH (rhGH)/somatropin alone or preceded by the VEGFR2 antagonist WAG-4S for 7 days. rhGH/somatropin reduced bodyweight loss and plasma endotoxin, maintained the hyperthermic state, and improved motor/memory functions. Additionally, rhGH/somatropin increased the junctional E-cadherin and β-catenin pool in the cerebral cortex to enhance the BBB competency, effects that were abolished by VEGFR2 blockade. Also, it activated cortical VEGFR2/mammalian target of the Rapamycin (mTOR) axis to mitigate ERS. The latter was reflected by the deactivation of the inositol-requiring enzyme-1α (IRE1α)/spliced X-box binding protein-1 (XBP1s) trajectory and the reduction in the protein levels of the death markers, C/EBP homologous protein (CHOP)/growth arrest and DNA damage-153 (GADD153), c-jun-N-terminal kinase (JNK), and caspase-3 with the simultaneous augmentation of expression of the unfolded protein response transducer proteinkinaseR-like ERkinase (PERK). Furthermore, rhGH/somatropin suppressed the phosphorylation of eukaryotic initiation factor-2α (eIF2α), upregulated the gene expression of activating transcription factor-4 (ATF4), GADD34, and glucose-regulated protein-78/binding immunoglobulin (GRP78/Bip). Moreover, it increased the glutathione level and reduced lipid peroxidation in the cerebral cortex. The VEGFR2 antagonist reversed the effect of rhGH/somatropin on PERK and IRE1α and boosted the apoptotic markers but neither affected p-eIF2α nor GADD34. Hence, we conclude that VEGFR2 activation by rhGH/somatropin plays a crucial role in assembling the BBB adherens junctions via its antioxidant capacity, ERS relief, and reducing endotoxemia in septic encephalopathy.

The Adroitness of Andrographolide as a Natural Weapon Against Colorectal Cancer

The conventional carcinoma treatment generally encompasses the employment of radiotherapy, chemotherapy, surgery or use of cytotoxic drugs. However, recent advances in pharmacological research have divulged the importance of traditional treatments in cancer. The aim of the present review is to provide an overview of the importance of one such medicinal herb of Chinese and Indian origin: Andrographis paniculate on colorectal cancer with special emphasis on its principal bioactive component andrographolide (AGP) and its underlying mechanisms of action. AGP has long been known to possess medicinal properties. Studies led by numerous groups of researchers shed light on its molecular mechanism of action. AGP has been shown to act in a multi-faceted manner in context of colorectal cancer by targeting matrix metalloproteinase-9, Toll-like receptor or NFκB signaling pathways. In this review, we highlighted the recent studies that show that AGP can act as an effective immunomodulator by harnessing effective anti-tumor immune response. Recent studies strongly recommend further research on this compound and its analogues, especially under in-vivo condition to assess its actual potential as a prospective and efficient candidate against colorectal cancer. The current review deals with the roles of this phytomedicine in context of colorectal cancer and briefly describes its perspectives to emerge as an essential anti-cancer drug candidate. Finally, we also point out the drawbacks and difficulties in administration of AGP and indicate the use of nano-formulations of this phytomedicine for better therapeutic efficacy.

Bifidobacterium dentium-derived y-glutamylcysteine suppresses ER-mediated goblet cell stress and reduces TNBS-driven colonic inflammation

Endoplasmic reticulum (ER) stress compromises the secretion of MUC2 from goblet cells and has been linked with inflammatory bowel disease (IBD). Although Bifidobacterium can beneficially modulate mucin production, little work has been done investigating the effects of Bifidobacterium on goblet cell ER stress. We hypothesized that secreted factors from Bifidobacterium dentium downregulate ER stress genes and modulates the unfolded protein response (UPR) to promote MUC2 secretion. We identified by mass spectrometry that B. dentium secretes the antioxidant γ-glutamylcysteine, which we speculate dampens ER stress-mediated ROS and minimizes ER stress phenotypes. B. dentium cell-free supernatant and γ-glutamylcysteine were taken up by human colonic T84 cells, increased glutathione levels, and reduced ROS generated by the ER-stressors thapsigargin and tunicamycin. Moreover, B. dentium supernatant and γ-glutamylcysteine were able to suppress NF-kB activation and IL-8 secretion. We found that B. dentium supernatant, γ-glutamylcysteine, and the positive control IL-10 attenuated the induction of UPR genes GRP78, CHOP, and sXBP1. To examine ER stress in vivo, we first examined mono-association of B. dentium in germ-free mice which increased MUC2 and IL-10 levels compared to germ-free controls. However, no changes were observed in ER stress-related genes, indicating that B. dentium can promote mucus secretion without inducing ER stress. In a TNBS-mediated ER stress model, we observed increased levels of UPR genes and pro-inflammatory cytokines in TNBS treated mice, which were reduced with addition of live B. dentium or γ-glutamylcysteine. We also observed increased colonic and serum levels of IL-10 in B. dentium- and γ-glutamylcysteine-treated mice compared to vehicle control. Immunostaining revealed retention of goblet cells and mucus secretion in both B. dentium- and γ-glutamylcysteine-treated animals. Collectively, these data demonstrate positive modulation of the UPR and MUC2 production by B. dentium-secreted compounds.

Disease-Dependent Antiapoptotic Effects of Cannabidiol for Keratinocytes Observed upon UV Irradiation

Although apoptosis of keratinocytes has been relatively well studied, there is a lack of information comparing potentially proapoptotic treatments for healthy and diseased skin cells. Psoriasis is a chronic autoimmune-mediated skin disease manifested by patches of hyperproliferative keratinocytes that do not undergo apoptosis. UVB phototherapy is commonly used to treat psoriasis, although this has undesirable side effects, and is often combined with anti-inflammatory compounds. The aim of this study was to analyze if cannabidiol (CBD), a phytocannabinoid that has anti-inflammatory and antioxidant properties, may modify the proapoptotic effects of UVB irradiation in vitro by influencing apoptotic signaling pathways in donor psoriatic and healthy human keratinocytes obtained from the skin of five volunteers in each group. While CBD alone did not have any major effects on keratinocytes, the UVB treatment activated the extrinsic apoptotic pathway, with enhanced caspase 8 expression in both healthy and psoriatic keratinocytes. However, endoplasmic reticulum (ER) stress, characterized by increased expression of caspase 2, was observed in psoriatic cells after UVB irradiation. Furthermore, decreased p-AKT expression combined with increased 15-d-PGJ₂ level and p-p38 expression was observed in psoriatic keratinocytes, which may promote both apoptosis and necrosis. Application of CBD partially attenuated these effects of UVB irradiation both in healthy and psoriatic keratinocytes, reducing the levels of 15-d-PGJ₂, p-p38 and caspase 8 while increasing Bcl2 expression. However, CBD increased p-AKT only in UVB-treated healthy cells. Therefore, the reduction of apoptotic signaling pathways by CBD, observed mainly in healthy keratinocytes, suggests the need for further research into the possible beneficial effects of CBD.

A Nudibranch Marine Extract Selectively Chemosensitizes Colorectal Cancer Cells by Inducing ROS-Mediated Endoplasmic Reticulum Stress

The present study shows the putative antiproliferative mechanism of action of the previously analytically characterized nudibranch extract (Dolabella auricularia, NB) and its different effects in colon cancer cells vs. nontumor colon cells. NB extract increased the accumulation of reactive oxygen species (ROS) and increased endoplasmic reticulum (ER) stress via stimulation of the unfolded protein response. Stress scavengers, N-acetylcysteine (NAC) and 4-phenylbutyric acid (4-PBA), decreased the stress induced by NB. The results showed that NB extract increased ER stress through overproduction of ROS in superinvasive colon cancer cells, decreased their resistance threshold, and produced a nonreturn level of ER stress, causing DNA damage and cell cycle arrest, which prevented them from achieving hyperproliferative capacity and migrating to and invading other tissues. On the contrary, NB extract had a considerably lower effect on nontumor human colon cells, suggesting a selective effect related to stress balance homeostasis. In conclusion, our results confirm that the growth and malignancy of colon cancer cells can be decreased by marine compounds through the modification of one of the most potent resistance mechanisms present in tumor cells; this characteristic differentiates cancer cells from nontumor cells in terms of stress balance.

Andrographolide - A prospective remedy for chikungunya fever and viral arthritis

AIM

Andrographolide, the major bioactive compound of the plant Andrographis paniculata, exerts anti-inflammatory, cyto-, neuro- and hepato-protective effects. Traditional remedies for infectious diseases include A. paniculata for maladies like fever, pain, rashes which are associated with chikungunya and other arboviral diseases. Since andrographolide and A. paniculata have potent antiviral properties, the present review aims to provide a comprehensive report of symptoms and immunological molecules involved in chikungunya virus (CHIKV) infection and the therapeutic role of andrographolide in the mitigation of chikungunya and associated symptoms.

MATERIALS AND METHODS

Studies on the therapeutic role of A. paniculata and andrographolide in chikungunya and other viral infections published between 1991 and 2021 were searched on various databases.

RESULTS AND DISCUSSION

The havoc created by chikungunya is due to the associated debilitating symptoms including arthralgia and myalgia which sometimes remains for years. The authors reviewed and summarized the various symptoms and immunological molecules related to CHIKV replication and associated inflammation, oxidative and unfolded protein stress, apoptosis and arthritis. Additionally, the authors suggested andrographolide as a remedy for chikungunya and other arboviral infections by highlighting its role in the regulation of molecules involved in unfolded protein response pathway, immunomodulation, inflammation, virus multiplication, oxidative stress, apoptosis and arthritis.

CONCLUSION

The present review demonstrated the major complications associated with chikungunya and the role of andrographolide in alleviating the chikungunya associated symptoms to encourage further investigations using this promising compound towards early development of an anti-CHIKV drug. Chemical Compound studied: andrographolide (PubChem CID: 5318517).

A Comprehensive Overview of Colon Cancer- A Grim Reaper of the 21st Century

A few decades ago, the incidence of colorectal cancer (CRC) was low and is now the fourth in the list of deadly cancers producing nearly a million deaths annually. A population that is aging along with risk factors such as smoking, obesity, sedentary lifestyle with little or no physical activity, and non-healthy food habits of developed countries can increase the risk of colorectal cancer. The balance in gut microbiota and the metabolites produced during bacterial fermentation within the host plays a significant role in regulating intestinal diseases as well as colorectal cancer development. Recent progress in the understanding of illness resulted in multiple treatment options such as surgery, radiation, and chemotherapy, including targeted therapy and multitherapies. The treatment plan for CRC depends on the location, stage and grade of cancer as well as genomic biomarker tests. Despite all the advancements made in the genetic and molecular aspects of the disease, the knowledge seems inadequate as the drug action as well as the wide variation in drug response did not appear strongly correlated with the individual molecular and genetic characteristics, which suggests the requirement of comprehensive molecular understanding of this complex heterogeneous disease. Furthermore, multitherapies or a broad spectrum approach, which is an amalgamation of the various promising as well as effective therapeutic strategies that can tackle heterogeneity and act on several targets of the disease, need to be validated in clinical studies. The latest treatment options have significantly increased the survival of up to three years in the case of advanced disease. The fact that colorectal cancer is developed from a polypoid precursor, as well as the symptoms of the disease that occur at an advanced stage, underlines how screening programs can help early detection and decrease mortality as well as morbidity from CRC.

The regulation of miR-320a/XBP1 axis through LINC00963 for endoplasmic reticulum stress and autophagy in diffuse large B-cell lymphoma

Background

This study incorporates fundamental research referring to considerable amounts of gene-sequencing data and bioinformatics tools to analyze the pathological mechanisms of diffuse large B-cell lymphoma (DLBCL).

Methods

A lncRNA-miRNA-mRNA ceRNA network of DLBCL was constructed through database analysis combining GTEx and TCGA. qPCR was used to detect the expression of LINC00963 and miR-320a in DLBCL cell lines. After LINC00963 or miR-320a overexpression in vitro, western blot was performed to assess the protein levels of UPR sensors (GRP78, p-IRE1, IRE1, active ATF6, ATF4 and XBP1), along with apoptosis markers (Bcl-2, Bax, caspase 3) and autophagy indicators (Beclin1, LC3II, LC3I and p62). Additionally, the expression of LC3 was analyzed through immunofluorescence (IF) assay. 

Results

Following LINC00963 overexpression in vitro, SUDHL4 cell line showed a marked increase in the level of UPR-related GRP78, p-IRE1 and spliced XBP-1/XBP-1(s), apoptosis-related Bax and cleaved caspase 3, as well as autophagy-related Beclin1 and LC3II, whereas miR-320a mimic greatly diminished the effects of LINC00963 overexpression. Moreover, LINC00963 targeted miR-320a while miR-320a bound to the 3’UTR of XBP1. It was also found that LINC00963 overexpression resulted in significantly delayed tumor growth in a xenograft model of DLBCL. 

Conclusion

Mechanistically, LINC00963/miR-320a regulated XBP1-apoptosis pathway and autophagy, implying the therapeutic potential of this pathway for selective targeting. The data presented here illustrated the mechanism of LINC00963/miR-320a/XBP1 in DLBCL for the first time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01992-y.

Impact of Andrographolide and Melatonin Combinatorial Drug Therapy on Metastatic Colon Cancer Cells and Organoids

Background:

The death rate (the number of deaths per 100 000 people per year) of colorectal cancer (CRC) has been dropping since 1980 due to increased screening, lifestyle-related risk factors, and improved treatment options; however, CRC is the third leading cause of cancer-related deaths in men and women in the United States. Therefore, successful therapy for CRC is an unmet clinical need. This study aimed to investigate the impacts of andrographolide (AGP) and melatonin (MLT) on CRC and the underlying mechanism.

Methods:

To investigate AGP and MLT anticancer effects, a series of metastatic colon cancer cell lines (T84, Colo 205, HT-29, and DLD-1) were selected. In addition, a metastatic patient-derived organoid model (PDOD) was used to monitor the anticancer effects of AGP and MLT. A series of bioassays including 3D organoid cell culture, MTT, colony formation, western blotting, immunofluorescence, and quantitative polymerase chain reaction (qPCR) were performed.

Results:

The dual therapy significantly promotes CRC cell death, as compared with the normal cells. It also limits CRC colony formation and disrupts the PDOD membrane integrity along with decreased Ki-67 expression. A significantly higher cleaved caspase-3 and the endoplasmic reticulum (ER) stress proteins, IRE-1 and ATF-6 expression, by 48 hours were found. This combinatorial treatment increased reactive oxygen species (ROS) levels. Apoptosis signaling molecules BAX, XBP-1, and CHOP were significantly increased as determined by qPCR.

Conclusions:

These findings indicated that AGP and MLT associated ER stress-mediated apoptotic metastatic colorectal cancer (mCRC) cell death through the IRE-1/XBP-1/CHOP signaling pathway. This novel combination could be a potential therapeutic strategy for mCRC cells.

Triazoloacridone C-1305 impairs XBP1 splicing by acting as a potential IRE1α endoribonuclease inhibitor

Inositol requiring enzyme 1 alpha (IRE1α) is one of three signaling sensors in the unfolding protein response (UPR) that alleviates endoplasmic reticulum (ER) stress in cells and functions to promote cell survival. During conditions of irrevocable stress, proapoptotic gene expression is induced to promote cell death. One of the three signaling stressors, IRE1α is an serine/threonine-protein kinase/endoribonuclease (RNase) that promotes nonconventional splicing of XBP1 mRNA that is translated to spliced XBP1 (XBP1s), an active prosurvival transcription factor. Interestingly, elevated IRE1α and XBP1s are both associated with poor cancer survival and drug resistance. In this study, we used next-generation sequencing analyses to demonstrate that triazoloacridone C-1305, a microtubule stabilizing agent that also has topoisomerase II inhibitory activity, dramatically decreases XBP1s mRNA levels and protein production during ER stress conditions, suggesting that C-1305 does this by decreasing IRE1α’s endonuclease activity.

MANF protects pancreatic acinar cells against alcohol-induced endoplasmic reticulum stress and cellular injury

BACKGROUND/PURPOSE

Heavy alcohol drinking is associated with pancreatitis. Pancreatitis is initiated by the damage to the pancreatic acinar cells. The endoplasmic reticulum (ER) stress has been shown to play an important role in alcohol-induced pancreatic damage. Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an ER stress-inducible protein. The aim of the study was to determine whether MANF can ameliorate alcohol-induced ER stress and cellular damages to pancreatic acinar cells.

METHODS

Alcohol-induced damage to mouse pancreatic 266-6 acinar cells was determined by MTT and flow cytometry. MANF expression was downregulated by MANF siRNA using the Neon Transfection System. The overexpression of MANF was performed by the infection with the adenoviral vector carrying mouse MANF gene. The expression of ER stress markers was determined by immunoblotting and immunofluorescence.

RESULTS

Alcohol caused ER stress, oxidative stress and induced apoptosis of 266-6 acinar cells. Recombinant human MANF alleviated alcohol-induced ER stress and cell death by inhibiting IRE1-caspase 12-caspase 3 apoptotic pathway. Overexpression of mouse MANF also protected cells against alcohol-induced apoptosis. In contrast, inhibiting MANF by siRNA exacerbated alcohol-induced cellular damage.

CONCLUSIONS

MANF was protective against alcohol-induced ER stress and cellular injury in pancreatic acinar cells. The findings suggest a potential therapeutic value of MANF for alcoholic pancreatitis.

Synergistic potential of dual andrographolide and melatonin targeting of metastatic colon cancer cells: Using the Chou-Talalay combination index method

Colorectal cancer (CRC) mortality has diminished for decades due to new and improved treatment profiles. However, CRC still ranks as the third most diagnosed cancer in the US. Therefore, a new therapeutic approach is needed to overcome colospheroids inhibition and drug resistance. It is well documented that andrographolide (AGP) and melatonin (MLT) have anti-carcinogenic properties. Our goal was to evaluate their synergistic effects on metastatic colon cancer cells (mCRC) and colospheroids. HT-29 and HCT-15 mCRC cells were simultaneously treated with serial dilutions of AGP and MLT for 24, 48 and 72 h. Cell viability was monitored using the MTT assay. The Chou-Talalay method for drug combination is based on the median effect equation, providing a theoretical basis for the combination index and the isobologram equation. This allows quantitative determination of drug interactions using the CompuSyn software, where CI < 1, = 1, and >1 indicates synergistic, additive, and antagonistic effects respectively. Our results demonstrate that AGP and MLT in combination show synergism with CI values of 0.35293 and 0.34152 for HT-29 and HCT-15 respectively and a fractional inhibition of Fa = 0.50-0.90, as shown by the Fa-CI plot and isobologram. The synergism value was validated in colospheroids (HT-29-s and HCT-15-s) based on morphology, viability, and colony formation and in 5-FU drug resistant cell (HT-29R and HCT-116R) viability. The mechanism(s) of decreased cell viability are due to the induction of ER stress proteins and angiogenic inhibition. Our results provide rationale for using AGP in combination with MLT on mCRC.

In vitro anticancer activity of Eclipta alba whole plant extract on colon cancer cell HCT-116

BACKGROUNDS

Colon cancer is the third most deadly and one of the most diagnosed diseases in the world. Although routine screening and early detection during last decades has improved the survival, colon cancer still claims hundreds of thousands lives each year worldwide. Surgery and chemotherapy is mainstay of current treatment, nevertheless toxicity associated with this treatment underscores the urgency of demand of a better therapeutics. Close to 50% of current chemotherapeutic drugs are direct or indirect descendants compounds isolated from medicinal plants, which indicate plants are great potential sources of novel therapeutics. In our literature review we found Eclipta alba to posses many pharmacological activities, including those with anticancer potentials. However, no study on anticancer activity of this kind has been reported.

METHODS

Phytochemicals were extracted by maceration method from shade dried whole plant of Eclipta alba using methanol as a solvent. The anticancer effect of extract was investigated on various cancer cell lines like human colorectal carcinoma (HCT-116), human prostate cancer (PC-3), Michigan cancer foundation-breast cancer (MCF-7) and renal cell carcinoma (RCC-45). We have also studied the effects on normal human embryonic lung fibroblast cell (WI-38) using MTT (methyl thiazoldiphenyltetrazolium bromide) assay, clonogenic (colony formation) and migration assay. Finally obtained results were analyzed using ANNOVA and Dunnett's test.

RESULTS

Results obtained from MTT assay revealed that the methanolic extract of Eclipta alba carried significant (p < 0.005) specificity against HCT-116 cells as compared to the other cancer cells. This extract also showed minimal or nontoxicity to WI-38 cells. Migration as well as clonogenic assays also confirmed the anticancer potential of the extract against HCT-116 cells.

CONCLUSION

This is a unique finding of its kind because the specific anticancer effect with minimal toxicity on normal cells has not been reported on Eclipta alba extract. Finally this finding opens up a great possibility to develop a novel antitumor drug candidate against deadly colon cancer in the future.

Andrographolide and Its 14-Aryloxy Analogues Inhibit Zika and Dengue Virus Infection

Andrographolide is a labdene diterpenoid with potential applications against a number of viruses, including the mosquito-transmitted dengue virus (DENV). In this study, we evaluated the anti-viral activity of three 14-aryloxy analogues (ZAD-1 to ZAD-3) of andrographolide against Zika virus (ZIKV) and DENV. Interestingly, one analogue, ZAD-1, showed better activity against both ZIKV and DENV than the parental andrographolide. A two-dimension (2D) proteomic analysis of human A549 cells treated with ZAD-1 compared to cells treated with andrographolide identified four differentially expressed proteins (heat shock 70 kDa protein 1 (HSPA1A), phosphoglycerate kinase 1 (PGK1), transketolase (TKT) and GTP-binding nuclear protein Ran (Ran)). Western blot analysis confirmed that ZAD-1 treatment downregulated expression of HSPA1A and upregulated expression of PGK1 as compared to andrographolide treatment. These results suggest that 14-aryloxy analogues of andrographolide have the potential for further development as anti-DENV and anti-ZIKV agents.

Endogenous Anti-Cancer Candidates in GPCR, ER Stress, and EMT

The majority of cellular responses to external stimuli are mediated by receptors such as G protein-coupled receptors (GPCRs) and systems including endoplasmic reticulum stress (ER stress). Since GPCR signalling is pivotal in numerous malignancies, they are widely targeted by a number of clinical drugs. Cancer cells often negatively modulate GPCRs in order to survive, proliferate and to disseminate. Similarly, numerous branches of the unfolded protein response (UPR) act as pro-survival mediators and are involved in promoting cancer progression via mechanisms such as epithelial to mesenchymal transition (EMT). However, there are a few proteins among these groups which impede deleterious effects by orchestrating the pro-apoptotic phenomenon and paving a therapeutic pathway. The present review exposes and discusses such critical mechanisms and some of the key processes involved in carcinogenesis.

Calreticulin promotes EMT in pancreatic cancer via mediating Ca2+ dependent acute and chronic endoplasmic reticulum stress

Background

Our previous study showed that calreticulin (CRT) promoted EGF-induced epithelial-mesenchymal transition (EMT) in pancreatic cancer (PC) via Integrin/EGFR-ERK/MAPK signaling. We next investigated the novel signal pathway and molecular mechanism involving the oncogenic role of CRT in PC.

Methods

We investigated the potential role and mechanism of CRT in regulating intracellular free Ca²⁺ dependent acute and chronic endoplasmic reticulum stress (ERS)-induced EMT in PC in vitro and vivo.

Results

Thapsigargin (TG) induced acute ERS via increasing intracellular free Ca²⁺ in PC cells, which was reversed by CRT silencing. Additionally, CRT silencing inhibited TG-induced EMT in vitro by reversing TG-induced changes of the key proteins in EMT signaling (ZO-1, E-cadherin and Slug) and ERK/MAPK signaling (pERK). TG-promoted cell invasion and migration was also rescued by CRT silencing but enhanced by IRE1α silencing (one of the key stressors in unfolded protein response). Meanwhile, CRT was co-immunoprecipitated and co-localized with IRE1α in vitro and its silencing led to the chronic ERS via upregulating IRE1α independent of IRE1-XBP1 axis. Moreover, CRT silencing inhibited IRE1α silencing-promoted EMT, including inhibiting the activation of EMT and ERK/MAPK signaling and the promotion of cell mobility. In vivo, CRT silencing decreased subcutaneous tumor size and distant liver metastasis following with the increase of IRE1α expression. A negative relationship between CRT and IRE1α was also observed in clinical PC samples, which coordinately promoted the advanced clinical stages and poor prognosis of PC patients.

Conclusions

CRT promotes EMT in PC via mediating intracellular free Ca²⁺ dependent TG-induced acute ERS and IRE1α-mediated chronic ERS via Slug and ERK/MAPK signaling.

Andrographolide Mitigates Unfolded Protein Response Pathway and Apoptosis Involved in Chikungunya Virus Infection

BACKGROUND

Chikungunya virus (CHIKV) is an arthropod-borne RNA virus which induces host Endoplasmic Reticulum (ER) stress by accumulating unfolded or misfolded proteins. ER stress activates the unfolded protein response (UPR) pathway to enable proper protein folding and maintain cellular homeostasis. There is no approved drug or vaccine available for CHIKV treatment, therefore, a pharmacological countermeasure is warranted for preventing CHIKV infection.

OBJECTIVE

With a view to find a treatment modality for chikungunya infection, "andrographolide", a plant-derived diterpenoid with reported antiviral, anti-inflammatory and immunomodulatory effects, was used to investigate its role in chikungunya induced unfolded protein stress and apoptosis.

METHODS

Cells and supernatant collected on andrographolide and VER-155008, a GRP78 inhibitor, treatment in CHIKV infected and mock-infected THP-1 cells were tested for differential expression of UPR pathway proteins including GRP78, PERK, EIF-2&#945;, IRE-1&#945;, XBP-1 and ATF6. Furthermore, the inflammasome and apoptosis pathway proteins, i.e., caspase-1, caspase-3 and PARP, were tested by immunoblotting, and cytokines, i.e., IL-1&#946;, IL-6 and IFN-&#947; were tested by ELISA.

RESULTS

Andrographolide treatment in CHIKV infected THP-1 cells significantly reduced IRE1α and downstream spliced XBP1 protein expression. Furthermore, CHIKV induced apoptosis and viral protein expression were also reduced on andrographolide treatment. A comparative analysis of andrographolide versus VER-155008, confirmed that andrographolide surpasses the effects of VER-155008 in suppressing the CHIKV induced ER stress.

CONCLUSION

The study, therefore, confirms that andrographolide is a potential remedy for chikungunya infection and suppresses CHIKV induced ER stress and apoptosis.

Modulation of endoplasmic reticulum stress response in gut-origin encephalopathy: Impact of vascular endothelial growth factor receptor-2 manipulation

BACKGROUND

Septic encephalopathy, the most frequent complication of sepsis, is orchestrated by a complex interplay of signals that leads to high mortality rates among intensive care unit patients. However, the role of the vascular endothelial growth factor receptor-2 (VEGFR2) in endoplasmic reticulum stress response (ERSR), during septic encephalopathy, is still elusive.

AIM

This study was aimed to examine the effect of an in-house designed/synthesized VEGFR2 antagonist, named WAG4S, on septic encephalopathy using cecal ligation and perforation (CLP).

MAIN METHODS

Rats were intraperitoneally injected with WAG-4S (1 mg/kg/d) for 7 days post-CLP.

KEY FINDINGS

In septic animals, VEGFR2 antagonism declined the expression of cortical p-VEGFR2 and p-mammalian target of rapamycin complex-1 (p-mTORC1). It also worsened the behavioral and histopathological alterations beyond CLP. However, and contrary to CLP, WAG-4S decreased the p-protein kinase R-like ER kinase (p-PERK) and eukaryotic initiation factor-2α (p-eIF2α) expression. Moreover, VEGFR2 blockade upregulated the mRNA expression of activating transcription factor-4 (ATF4), binding immunoglobulin protein/glucose-regulated protein-78 (Bip/GRP78), growth arrest and DNA damage-34 (GADD34) and spliced X-box binding protein-1 (XBP1s) above CLP. Similarly, it boosted inositol requiring enzyme-1α (IRE1α) activation and redox imbalance. In the same context, WAG-4S augmented the protein levels of CLP-induced ERSR apoptotic markers, namely C/EBP homologous protein (CHOP/GADD153), c-jun N-terminal kinase (JNK) and caspase-3.

SIGNIFICANCE

In conclusion, the PERK/eIF2α axis inhibition, during septic encephalopathy, is VEGFR2-independent, whereas the activated IRE1α/XBP1s/CHOP/JNK/caspase-3 cue promotes the ERSR execution module through VEGFR2 inhibition. This has turned VEGFR2 into a potential therapeutic target for ameliorating such an ailment.

Crosstalk between endoplasmic reticulum stress and anti-viral activities: A novel therapeutic target for COVID-19

The outbreak of COVID-19 caused by 2019–nCov/SARS-CoV-2 has become a pandemic with an urgent need for understanding the mechanisms and identifying a treatment. Viral infections including SARS-CoV are associated with increased levels of reactive oxygen species, disturbances of Ca⁺⁺ caused by unfolded protein response (UPR) mediated by endoplasmic reticulum (ER) stress and is due to the exploitation of virus's own protein i.e., viroporins into the host cells. Several clinical trials are on-going including testing Remdesivir (anti-viral), Chloroquine and Hydroxychloroquine derivatives (anti-malarial drugs) etc. Unfortunately, each drug has specific limitations. Herein, we review the viral protein involvement to activate ER stress transducers (IRE-1, PERK, ATF-6) and their downstream signals; and evaluate combination therapies for COVID-19 mediated ER stress alterations. Melatonin is an immunoregulator, anti-pyretic, antioxidant, anti-inflammatory and ER stress modulator during viral infections. It enhances protective mechanisms for respiratory tract disorders. Andrographolide, isolated from Andrographis paniculata, has versatile biological activities including immunomodulation and determining SARS-CoV-2 binding site. Considering the properties of both compounds in terms of anti-inflammatory, antioxidant, anti-pyrogenic, anti-viral and ER stress modulation and computational approaches revealing andrographolide docks with the SARS-CoV2 binding site, we predict that this combination therapy may have potential utility against COVID-19.

Andrographolide alleviates Parkinsonism in MPTP-PD mice via targeting mitochondrial fission mediated by dynamin-related protein 1

BACKGROUND AND PURPOSE

Accumulating evidence indicates that mitochondrial dynamics play an important role in the progressive deterioration of dopaminergic neurons. Andrographolide has been found to exert neuroprotective effects in several models of neurological diseases. However, the mechanism of how andrographolide protects neurons in Parkinson's disease (PD) remains not fully understood.

EXPERIMENTAL APPROACH

Behavioural experiments were performed to examine the effect of andrographolide in 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-PD mice. Mitochondrial mass and morphology were visualized using transmission electron microscopy (TEM). SH-SY5Y cells and primary mouse neurons were exposed to rotenone to mimic PD in vitro. Western blotting, co-immunoprecipitation and immunofluorescence were performed. The target protein of andrographolide was identified by biotin-andrographolide pulldown assay as well as drug affinity responsive target stability (DARTS), cellular thermal shift (CETSA), and surface plasmon resonance (SPR) assays.

KEY RESULTS

Andrographolide administration improved behavioural deficits and attenuated loss of dopaminergic neurons in MPTP-exposed mice and reduced cell death induced by rotenone in vitro. An increased mitochondrial mass, and decreased surface area were found in the striatum from MPTP-PD mice, as well as in rotenone-treated primary neurons and SH-SY5Y cells, while andrographolide treatment preserved mitochondrial mass and morphology. Dynamin-related protein 1 (DRP1) was identified as a target protein of andrographolide. Andrographolide bound to DRP1 and inhibited its GTPase activity, thereby preventing excessive mitochondria fission and neuronal damage in PD.

CONCLUSIONS AND IMPLICATIONS

Our findings suggest that andrographolide may protect neurons against rotenone- or MPTP-induced damage in vitro and in vivo through inhibiting mitochondrial fission.

Bursopentin (BP5) induces G1 phase cell cycle arrest and endoplasmic reticulum stress/mitochondria-mediated caspase-dependent apoptosis in human colon cancer HCT116 cells

Background

Bursopentin (BP5) is a multifunctional pentapeptide found in the chicken bursa of Fabricius. Recent study indicated that BP5 significantly stimulates expression of p53 protein in colon cancer HCT116 cells. However, the effects and underlying mechanisms of BP5 on HCT116 cell proliferation remain largely unclear.

Methods

Analyses of cell viability, cell cycle arrest as well as apoptosis were performed to study the actions of BP5 on HCT116 cells. Western blot analyse was assayed to measure the cell cycle-related and apoptosis-related proteins. Specific siRNAs targeting IRE1, ATF-6, and PERK were used for IRE1, ATF-6, and PERK knockdown, respectively. Cellular reactive oxygen species (ROS) were detected using a H₂DCF-DA green fluorescence probe. Cytosolic free Ca²⁺ concentrations and mitochondrial membrane potential (ΔΨm) were measured using Fluo-3 AM and JC-1 stains, respectively.

Results

BP5 possessed strong inhibitory effects on the cell growth and induced apoptosis in HCT116 cells. Mechanistically, BP5 arrested the cell cycle at G1 phase by increasing p53 and p21 expression and decreasing cyclin E1-CDK2 complex expression. BP5 treatment dramatically activated the endoplasmic reticulum (ER) stress-mediated apoptotic pathway, as revealed by the significantly enhanced expression of unfolded protein response (UPR) sensors (IRE1α, ATF6, PERK) as well as downstream signaling molecules (XBP-1s, eIF2α, ATF4 and CHOP), and by the significantly altered the BP5-induced phenotypic changes in IRE1, ATF6, and PERK knockdown cells. Additionally, BP5-induced ER stress was accompanied by the accumulation of cytosolic free Ca²⁺ and intracellular ROS. Furthermore, BP5 treatment resulted in the increase of Bax expression, the decrease of Bcl-2 expression and the reduction of ΔΨm, subsequently causing a release of cytochrome c from the mitochondria into the cytoplasm and finally enhancing the activities of caspase-9 and -3. In addition, z-VAD-fmk, a pan-caspase inhibitor, markedly rescued BP5-induced cell viability reduction and reduced BP5-induced apoptosis.

Conclusions

Our present results suggest that BP5 has an anticancer capacity to arrest cell cycle at G1 phase and to trigger ER stress/mitochondria-mediated caspase-dependent apoptosis in HCT116 cells. Therefore, our findings provide insight into further investigations of the anticancer activities of BP5.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0849-3) contains supplementary material, which is available to authorized users.

Andrographolide sensitizes prostate cancer cells to TRAIL-induced apoptosis

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent for anticancer therapy. The identification of small molecules that can establish the sensitivity of prostate cancer (PCa) cells to TRAIL-induced apoptosis is crucial for the targeted treatment of PCa. PC3, DU145, JAC-1, TsuPr1, and LNCaP cells were treated with Andrographolide (Andro) and TRAIL, and the apoptosis was measured using the Annexin V/PI double staining method. Real time-polymerase chain reaction (PCR) and Western blot analysis were performed to measure the expression levels of target molecules. RNA interference technique was used to down-regulate the expression of the target protein. We established a nude mouse xenograft model of PCa, which was used to measure the caspase-3 activity in the tumor cells using flow cytometry. In this research study, our results demonstrated that Andro preferentially increased the sensitivity of PCa cells to TRAIL-induced apoptosis at subtoxic concentrations, and the regulation mechanism was related to the up-regulation of DR4. In addition, it also increased the p53 expression and led to the generation of reactive oxygen species (ROS) in the cells. Further research revealed that the DR4 inhibition, p53 expression, and ROS generation can significantly reduce the apoptosis induced by the combination of TRAIL and Andro in PCa cells. In conclusion, Andro increases the sensitivity of PCa cells to TRAIL-induced apoptosis through the generation of ROS and up-regulation of p53 and then promotes PCa cell apoptosis associated with the activation of DR4.

ER Stress is Involved in Epithelial-To-Mesenchymal Transition of Alveolar Epithelial Cells Exposed to a Hypoxic Microenvironment

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive and fatal interstitial lung disease of unknown origin. Alveolar epithelial cells (AECs) play an important role in the fibrotic process as they undergo sustained endoplasmic reticulum (ER) stress, and may acquire a mesenchymal phenotype through epithelial-to-mesenchymal transition (EMT), two phenomena that could be induced by localized alveolar hypoxia. Here we investigated the potential links between hypoxia, ER stress and EMT in AECs. Methods: ER stress and EMT markers were assessed by immunohistochemistry, western blot and qPCR analysis, both in vivo in rat lungs exposed to normoxia or hypoxia (equivalent to 8% O₂) for 48 h, and in vitro in primary rat AECs exposed to normoxia or hypoxia (1.5% O₂) for 2–6 days. Results: Hypoxia induced expression of mesenchymal markers, pro-EMT transcription factors, and the activation of ER stress markers both in vivo in rat lungs, and in vitro in AECs. In vitro, pharmacological inhibition of ER stress by 4-PBA limited hypoxia-induced EMT. Calcium chelation or hypoxia-inducible factor (HIF) inhibition also prevented EMT induction under hypoxic condition. Conclusions: Hypoxia and intracellular calcium are both involved in EMT induction of AECs, mainly through the activation of ER stress and HIF signaling pathways.

MiR-451a suppressing BAP31 can inhibit proliferation and increase apoptosis through inducing ER stress in colorectal cancer

The global morbidity and mortality of colorectal cancer (CRC) are ranked the third among gastrointestinal tumors in the world. MiR-451a is associated with several types of cancer, including CRC. However, the roles and mechanisms of miR-451a in CRC have not been elucidated. BAP31 is a predicted target gene of miR-451a in our suppression subtractive hybridization library. Its relationship with miR-451a and function in CRC are unclear. We hypothesized that miR-451a could induce apoptosis through suppressing BAP31 in CRC. Immunohistochemistry and real-time PCR were used to measure BAP31 expressions in CRC tissues and pericarcinous tissues from 57 CRC patients and CRC cell lines. Dual-luciferase reporter assay was used to detect the binding of miR-451a to BAP31. The expression of BAP31 protein in CRC tissues was significantly higher than that in pericarcinous tissues, which was correlated with distant metastasis and advanced clinical stages of CRC patients. The expression of BAP31 was higher in HCT116, HT29, SW620, and DLD cells than that in the normal colonic epithelial cell line NCM460. The expression of BAP31 was absolutely down-regulated when over-expressing miR-451a in HCT116 and SW620 cells compared with control cells. Mir-451a inhibited the expression of BAP31 by binding to its 5'-UTR. Over-expressing miR-451a or silencing BAP31 suppressed the proliferation and apoptosis of CRC cells by increasing the expressions of endoplasmic reticulum stress (ERS)-associated proteins, including GRP78/BIP, BAX, and PERK/elF2α/ATF4/CHOP, which resulted in increased ERS, cytoplasmic calcium ion flowing, and apoptosis of CRC cells. These changes resulting from over-expressing miR-451a were reversed by over-expressing BAP31 with mutated miR-451a-binding sites. Over-expressing miR-451a or silencing BAP31 inhibited tumor growth by inducing ERS. The present study demonstrated that miR-451a can inhibit proliferation and increase apoptosis through inducing ERS by binding to the 5'-UTR of BAP31 in CRC.

Identification of Cross Talk between FoxM1 and RASSF1A as a Therapeutic Target of Colon Cancer

Metastatic colorectal cancer (mCRC) is characterized by the expression of cellular oncogenes, the loss of tumor suppressor gene function. Therefore, identifying integrated signaling between onco-suppressor genes may facilitate the development of effective therapy for mCRC. To investigate these pathways we utilized cell lines and patient derived organoid models for analysis of gene/protein expression, gene silencing, overexpression, and immunohistochemical analyses. An inverse relationship in expression of oncogenic FoxM1 and tumor suppressor RASSF1A was observed in various stages of CRC. This inverse correlation was also observed in mCRC cells lines (T84, Colo 205) treated with Akt inhibitor. Inhibition of FoxM1 expression in mCRC cells as well as in our ex vivo model resulted in increased RASSF1A expression. Reduced levels of RASSF1A expression were found in normal cells (RWPE-1, HBEpc, MCF10A, EC) stimulated with exogenous VEGF₁₆₅. Downregulation of FoxM1 also coincided with increased YAP phosphorylation, indicative of tumor suppression. Conversely, downregulation of RASSF1A coincided with FoxM1 overexpression. These studies have identified for the first time an integrated signaling pathway between FoxM1 and RASSF1A in mCRC progression, which may facilitate the development of novel therapeutic options for advanced colon cancer therapy.