The anti-proliferative and apoptotic effects of crocin on chemosensitive and chemoresistant cervical cancer cells

Therapeutic effects of saffron (Crocus sativus L) on female reproductive system disorders: A systematic review

The effect of Crocus sativus on several disorders has been discussed or even confirmed, but the efficacy of this herb on the female reproductive system has not been well presented. In this regard, this systematic review comprehensively discussed the efficacy of C. sativus and its main phytochemical compounds on the female reproductive system and its disorders for the first time. In this systematic review, scientific databases, including PubMed, Web of Sciences, Google Scholar, Scopus, and Scientific Information Database, were explored profoundly. In vivo, in vitro, and human studies published until the end of July 2023, which had investigated the pharmacological properties of C. sativus, crocin, crocetin, safranal, or picrocrocin on the female reproductive system, were selected. A total of 50 studies conducted on the effect of C. sativus on the female reproductive system were acquired. These studies confirmed the efficacy of C. sativus or its main phytochemical ingredients in several aspects of the female reproductive system, including regulation of sex hormones, folliculogenesis, ovulation, and protection of the ovary and uterus against several oxidative stress. Several retrieved studies indicated that this herb also can alleviate the symptoms of patients suffering from dysmenorrhea, premenstrual syndrome, menopause, polycystic ovary disease (PCOD), and sexual dysfunction. Furthermore, it is a promising candidate for future studies or even trials regarding ovarian and cervical cancers. This review concluded that C. sativus can improve the symptoms of several female reproductive system disorders, which is particularly due to the presence of phytochemical ingredients, such as crocin, crocetin, and safranal.

Research progress on the pharmacological activity, biosynthetic pathways, and biosynthesis of crocins

Crocins are water-soluble apocarotenoids isolated from the flowers of crocus and gardenia. They exhibit various pharmacological effects, including neuroprotection, anti-inflammatory properties, hepatorenal protection, and anticancer activity. They are often used as coloring and seasoning agents. Due to the limited content of crocins in plants and the high cost of chemical synthesis, the supply of crocins is insufficient to meet current demand. The biosynthetic pathways for crocins have been elucidated to date, which allows the heterologous production of these valuable compounds in microorganisms by fermentation. This review article provides a comprehensive overview of the chemistry, pharmacological activity, biosynthetic pathways, and heterologous production of crocins, aiming to lay the foundation for the large-scale production of these valuable natural products by using engineered microbial cell factories.

Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Concurrent Use of Crocin During Chemoradiation for Esophageal Squamous Cell Carcinoma

Crocin is the major active carotenoid of saffron (Crocus sativus L.). Its pluripotent effects have led to a growing body of literature investigating its antitumor properties as well as its diverse potentials for mood stabilization, normal tissue protection, and inflammation reduction; However, there is a gap in clinical trials testing this substance in cancer patients. In this randomized, double-blind, placebo-controlled clinical trial, patients with newly diagnosed esophageal squamous cell carcinoma were randomly assigned to either 30 mg/day of crocin or placebo, prescribed during the neoadjuvant chemo-radiotherapy. The primary endpoints were pathological response and toxicity, and secondary endpoints were depression and anxiety levels and survival analysis.

Combining Crocin and Sorafenib Improves Their Tumor-Inhibiting Effects in a Rat Model of Diethylnitrosamine-Induced Cirrhotic-Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies, with continuously increasing cases and fatalities. Diagnosis often occurs in the advanced stages, confining patients to systemic therapies such as sorafenib. Sorafenib (SB), a multi-kinase inhibitor, has not yet demonstrated sufficient efficacy against advanced HCC. There is a strong argument in favor of studying its use in combination with other medications to optimize the therapeutic results. According to our earlier work, crocin (CR), a key bioactive component of saffron, hinders HCC development and liver cancer stemness. In this study, we investigated the therapeutic use of CR or its combination with SB in a cirrhotic rat model of HCC and evaluated how effectively SB and CR inhibited tumor growth in this model. Diethylnitrosamine (DEN) was administered intraperitoneally to rats once a week for 15 weeks, leading to cirrhosis, and then 19 weeks later, leading to multifocal HCC. After 16 weeks of cancer induction, CR (200 mg/kg daily) and SB (10 mg/kg daily) were given orally to rats for three weeks, either separately or in combination. Consistently, the combination treatment considerably decreased the incidence of dyschromatic nodules, nodule multiplicity, and dysplastic nodules when compared to the HCC group of single therapies. Combined therapy also caused the highest degree of apoptosis, along with decreased proliferating and β-catenin levels in the tumor tissues. Additionally, when rats received combined therapy with CR, it showed anti-inflammatory characteristics where nuclear factor kappa B (NF-κB) and cyclooxygenase-2 (Cox-2) were considerably and additively lowered. As a result, CR potentiates the suppressive effects of SB on tumor growth and provides the opportunity to strengthen the therapeutic effects of SB in the treatment of HCC.

Advances on the anti-tumor mechanisms of the carotenoid Crocin

Saffron is located in the upper part of the crocus stigma of iridaceae, which has a long history of medicinal use. Crocin (molecular formula C44H64O24) is a natural floral glycoside ester compound extracted from saffron, which is a type carotenoid. Modern pharmacological studies have shown that crocin has multiple therapeutic effects including anti-inflammatory, anti-oxidant, anti-hyperlipidemic and anti-stone effects. In recent years, crocin has been widely noticed due to its considerable anti-tumor effects manifested by the induction of tumor cell apoptosis, inhibition of tumor cell proliferation, inhibition of tumor cell invasion and metastasis, enhancement of chemotherapy sensitivity and improvement of immune status. The anti-tumor effects have been shown in various malignant tumors such as gastric cancer, liver cancer, cervical cancer, breast cancer and colorectal cancer. In this review, we compiled recent studies on the anti-tumor effects of crocin and summarized its anti-tumor mechanism for developing ideas of treating malignancies and exploring anti-tumor drugs.

Modulating Effects of Cancer-Derived Exosomal miRNAs and Exosomal Processing by Natural Products

Cancer-derived exosomes exhibit sophisticated functions, such as proliferation, apoptosis, migration, resistance, and tumor microenvironment changes. Several clinical drugs modulate these exosome functions, but the impacts of natural products are not well understood. Exosome functions are regulated by exosome processing, such as secretion and assembly. The modulation of these exosome-processing genes can exert the anticancer and precancer effects of cancer-derived exosomes. This review focuses on the cancer-derived exosomal miRNAs that regulate exosome processing, acting on the natural-product-modulating cell functions of cancer cells. However, the role of exosomal processing has been overlooked in several studies of exosomal miRNAs and natural products. In this study, utilizing the bioinformatics database (miRDB), the exosome-processing genes of natural-product-modulated exosomal miRNAs were predicted. Consequently, several natural drugs that modulate exosome processing and exosomal miRNAs and regulate cancer cell functions are described here. This review sheds light on and improves our understanding of the modulating effects of exosomal miRNAs and their potential exosomal processing targets on anticancer treatments based on the use of natural products.

Yellow pigment from gardenia fruit: structural identification and evaluation of cytotoxic activity in HepG2 cells by induction of apoptosis

The preparation process of yellow pigment (YP) from gardenia (Gardenia jasminoides) fruit was investigated, and the main components of YP were characterized by liquid chromatography-time of flight-mass spectrometer/mass spectrometer (LC-TOF-MS/MS). Furthermore, cytotoxic activity in HepG2 cells by induction of apoptosis was also evaluated. The preparation results indicated that the color value of YP was 498.34, which was 8.6 times higher than crude YP. Fifteen compounds in YP were identified, and crocins were the predominant compounds. The cell experiment results showed that YP inhibited the proliferation of HepG2 cells in a time- and dose-dependent manner. Moreover, YP also inhibited HepG2 cells in G2/M stage, increased the level of intracellular reactive oxygen species (ROS), and enhanced cell apoptosis. Real-time quantitative polymerase chain reaction (RT-PCR) analysis revealed the up-regulation of caspase-3, 8, 9, and bax and down-regulation of bcl-2 in HepG2 cells. Overall, these findings suggested that YP had potential cytotoxic activity in HepG2 cells by induction of apoptosis, which might be beneficial to human health.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01133-9.

An In Vitro Study of Saffron Carotenoids: The Effect of Crocin Extracts and Dimethylcrocetin on Cancer Cell Lines

Crocus sativus L. has various pharmacological properties, known for over 3600 years. These properties are attributed mainly to biologically active substances, which belong to the terpenoid group and include crocins, picrocrocin and safranal. The aim of the current work was to examine the effects of crocins (CRCs) and their methyl ester derivate dimethylcrocetin (DMCRT) on glioblastoma and rhabdomyosarcoma cell lines, in terms of cytotoxicity and gene expression, implicated in proapoptotic and cell survival pathways. Cell cytotoxicity was assessed with Alamar Blue fluorescence assay after treatment with saffron carotenoids for 24, 48 and 72 h and concentrations ranging from 22.85 to 0.18 mg/mL for CRCs and 11.43 to 0.09 mg/mL for DMCRT. In addition, BAX, BID, BCL2, MYCN, SOD1, and GSTM1 gene expression was studied by qRT-PCR analysis. Both compounds demonstrated cytotoxic effects against glioblastoma and rhabdomyosarcoma cell lines, in a dose- and time-dependent manner. They induced apoptosis, via BAX and BID upregulation, MYCN and BCL-2, SOD1, GSTM1 downregulation. The current research denotes the possible anticancer properties of saffron carotenoids, which are considered safe phytochemicals, already tested in clinical trials for their health promoting properties.

Safranal Prevents Liver Cancer Through Inhibiting Oxidative Stress and Alleviating Inflammation

Despite all efforts, an effective and safe treatment for liver cancer remains elusive. Natural products and their derived biomolecules are potential resources to mine for novel anti-cancer drugs. Chemopreventive effects of safranal, a major bioactive ingredient of the golden spice "saffron", were evaluated in this study against diethylnitrosamine (DEN)-induced liver cancer in rats. Safranal's mechanisms of action were also investigated in the human liver cancer line "HepG2". When administered to DEN-treated rats, safranal significantly inhibited proliferation (Ki-67) and also induced apoptosis (TUNEL and M30 CytoDeath). It also exhibited anti-inflammatory properties where inflammatory markers such as NF-kB, COX2, iNOS, TNF-alpha, and its receptor were significantly inhibited. Safranal's in vivo effects were further supported in HepG2 cells where apoptosis was induced and inflammation was downregulated. In summary, safranal is reported here as a potent chemopreventive agent against hepatocellular carcinoma that may soon be an important ingredient of a broad-spectrum cancer therapy.

Evaluation of the Effect of Crocin on Doxorubicin-Induced Cardiotoxicity

Despite newer advances in cancer treatment, chemotherapy is still one of the most widely used treatment strategies in this field. However, this treatment strategy faces major challenges. Doxorubicin (Dox) is an effective chemotherapeutic agent used to treat various cancers. However, several studies have shown that the use of Dox in therapeutic concentrations is associated with serious side effects, such as cardiac toxicity. The use of natural products in combination with chemotherapeutic agents to reduce side effects is a novel approach, and several studies have shown promising results. In this regard, we examined the effect of Crocin on doxorubicin-induced cardiotoxicity in rat and H9c2 cell line. The in vitro model on H9C2 cells and the in vivo models on rats were treated with doxorubicin. Cell viability, DNA damage, and apoptosis were measured in H9C2 cell line in the presence and absence of Crocin. Oxidative stress and various inflammatory parameters, as well as cardiac function tests, also were assessed in doxorubicin-induced cardiotoxicity animal model in the presence and absence of Crocin. Our results showed that Crocin can significantly decrease apoptosis in H9C2 cell line through a reduction in ROS production and DNA damages. Moreover, evaluation of the effect of Crocin on doxorubicin-induced cardiotoxicity animal model showed that Crocin also can significantly reduce oxidative stress and inflammatory parameters in the serum of the animals. Assessment of cardiac function revealed that Crocin has a significant protective effect against doxorubicin-induced cardiotoxicity in the animal model. Our data indicate that Crocin significantly attenuated doxorubicin-induced cardiotoxicity. Hence, Crocin could be potentially used as an adjuvant treatment in combination with Dox to reduce cardiotoxicity.

The Pharmacological Activities of Crocus sativus L.: A Review Based on the Mechanisms and Therapeutic Opportunities of its Phytoconstituents

Crocus species are mainly distributed in North Africa, Southern and Central Europe, and Western Asia, used in gardens and parks as ornamental plants, while Crocus sativus L. (saffron) is the only species that is cultivated for edible purpose. The use of saffron is very ancient; besides the use as a spice, saffron has long been known also for its medical and coloring qualities. Due to its distinctive flavor and color, it is used as a spice, which imparts food preservative activity owing to its antimicrobial and antioxidant activity. This updated review discusses the biological properties of Crocus sativus L. and its phytoconstituents, their pharmacological activities, signaling pathways, and molecular targets, therefore highlighting it as a potential herbal medicine. Clinical studies regarding its pharmacologic potential in clinical therapeutics and toxicity studies were also reviewed. For this updated review, a search was performed in the PubMed, Science, and Google Scholar databases using keywords related to Crocus sativus L. and the biological properties of its phytoconstituents. From this search, only the relevant works were selected. The phytochemistry of the most important bioactive compounds in Crocus sativus L. such as crocin, crocetin, picrocrocin, and safranal and also dozens of other compounds was studied and identified by various physicochemical methods. Isolated compounds and various extracts have proven their pharmacological efficacy at the molecular level and signaling pathways both in vitro and in vivo. In addition, toxicity studies and clinical trials were analyzed. The research results highlighted the various pharmacological potentials such as antimicrobial, antioxidant, cytotoxic, cardioprotective, neuroprotective, antidepressant, hypolipidemic, and antihyperglycemic properties and protector of retinal lesions. Due to its antioxidant and antimicrobial properties, saffron has proven effective as a natural food preservative. Starting from the traditional uses for the treatment of several diseases, the bioactive compounds of Crocus sativus L. have proven their effectiveness in modern pharmacological research. However, pharmacological studies are needed in the future to identify new mechanisms of action, pharmacokinetic studies, new pharmaceutical formulations for target transport, and possible interaction with allopathic drugs.

Anticancer Effects of Valproic Acid via Regulation of Epigenetic Mechanisms in Non-small-cell Lung Cancer A549 Cell Line

Epigenetic mechanisms are the most important factors contributing to both the development and metastasis of cancer cells. We aimed to scrutinize the role of epigenetic alternations of genes involved in cancer metastasis, including CD44v6 (metastasis indicator) and Nm23-H1 (a novel tumor suppressor), in the A549 lung cancer cell line. The A549 cells were cultured in the DMEM medium. Valproic acid (VPA) was used as a histone deacetylase inhibitor. Caspase-3 activity was assessed by adding DEVD-pNA substrate to the cell lysate. Gene expression was determined by real-time PCR. Finally, protein expression was assessed by western blot. The results showed that VA significantly decreased the expression of the CD44v6 gene and its protein level. This was further accompanied by lower expressions of MMP-2 and MMP-9 genes. On the other hand, the expression of Nm23-H1 and its protein were significantly increased in the cells accompanied by higher activity of caspase-3 (P ˂ 0.05). Our results showed that epigenetic regulation of CD44v6, Nm23-H1, MMP-2, and MMP-9 might be involved in the pathogenesis and metastasis of lung cancer. Therefore, the use of histone deacetylase inhibitors can be effective in the suppression of metastases and the treatment of these tumors.

Crocins: A comprehensive review of structural characteristics, pharmacokinetics and therapeutic effects

Crocins, as a kind of water-soluble carotenoid pigment, are a series of ester compounds formed from crocetin and gentibiose or glucose, and mainly distributed among Crocus sativus L. (CSL), Gardenia jasminoides Ellis. (GJE). Crocins exhibit a wide range of pharmacological effects on neurodegeneration, cardiovascular disease, cerebrovascular disease, depression, liver disease, arthritis, tumor, diabetes, etc. This review systematically discussed the pharmacologic study of crocins in the aspect of structural characteristic and pharmacokinetics, and summarized the mechanism of treating disease. It summarized the abundant research of crocins from 1984 to 2020 based on the above aspects, which provide a reference for the deeply development and application of crocins.

Crocin and Metformin suppress metastatic breast cancer progression via VEGF and MMP9 downregulations: in vitro and in vivo studies

Metastatic breast cancer remains a serious health concern and numerous investigations recommended medicinal plants as a complementary therapy. Crocin is one of the known anticancer bio-component. Recently, the inhibitory effect of metformin has been studied on the various aspects of cancer. However, no study reported their combination effects on metastatic breast cancer. In the present study, we have assessed their anti-metastatic effects on in vitro and in vivo breast cancer models. Using MTT assay, scratch, and adhesion tests, we have evaluated the cytotoxic, anti-invasive and anti-adhesion effects of crocin and metformin on 4T1 cell line, respectively. Their protective effects and MMP9 as well as VEGF protein expression levels (Western blotting) investigated in the 4T1 murine breast cancer model. Our results showed that both crocin and metformin reduced cell viability, delayed scratch healing and inhibited the cell adhesion, in vitro. While crocin alone restored the mice's weight reduction, crocin, metformin, and their combination significantly reduced the tumor volume size and enhanced animal survival rate in murine breast cancer model, responses that were associated with VEGF and MMP9 down-regulation. These findings suggest that a combination of crocin and metformin could serve as a novel therapeutic approach to enhance the effectiveness of metastatic breast cancer therapy.

Study of the cardioprotective effects of crocin on Human Cardiac Myocyte cells and reduction of oxidative stress produced by aluminum phosphide poisoning

OBJECTIVES

The effects of Crocin as a cardioprotective material against Aluminum phosphide poisoning by reducing the oxidative stress is investigated.

METHODS

The level of biomarkers of oxidative stress (Catalase, Superoxide dismutase, Malondialdehyde and Protein carbonyl) were measured in the cell culture model on Human Cardiac Myocyte cells to detect the protective effect of crocin. Initially, to define the pure impact of aluminum phosphide poison and crocin on the heart cells, their effects on the biomarkers quantity in cell line were measured, separately, using the standard related kits. Later the effect of crocin with different concentration as a treatment on the oxidative stress biomarkers of the poisoned heart cells were monitored. Note that in pre-treatment case, the crocin was initially added to the cells before poisoning them. Data were analyzed using the analysis of variance method.

KEY FINDINGS

Results showed that crocin treatment reduced the aluminum phosphide (AlP) poisoning effect significantly. The treatment resulted in substantial deviation in the biomarkers of oxidative stress at the pre- and post-treatment phases for all groups. The oxidative markers values of the poisoned cells were recovered by crocin treatment.

CONCLUSIONS

Crocin is proposed as a potentially powerful antioxidant to treat the cardiotoxicity caused by aluminum phosphide poisoning.

Evaluation of anti-tumor effects of crocin on a novel 3D tissue-engineered tumor model based on sodium alginate/gelatin microbead

Crocin, as one of the biologically active components of saffron, has anti-inflammatory, anti-oxidant, anti-depressant and auxiliary anti-tumor effects. Studies have shown that crocin could promote breast cancer cell apoptosis. However, conventional methods are mainly based on two-dimensional (2D) cell culture models, which are difficult to reproduce the tumor environment in vivo due to space constraints. In this study, we prepared a three-dimensional (3D) cell model in vitro based on sodium alginate/gelatin to evaluate the inhibitory effect of crocin on MCF-7 cells, which could bridge the gap in crocin drug evaluation between 2D and 3D cell model in vitro. Different from the 2D culture, the cells were found to aggregate in a spherical shape in the 3D microgel beads. And the CCK-8 assay showed that the growth of MCF-7 cells exposed to crocin was inhibited in a time-related and concentration-related manner. Compared with 2D culture (IC₅₀ that MCF-7 cells treated with crocin at 24 h, 48 h, 72 h: 3.68, 2.55 and 1.53 mg/mL, respectively), the IC₅₀ value of 3D culture (IC₅₀ that MCF-7 cells treated with crocin at 24 h, 48 h, 72 h: 10.12, 6.89 and 6.64 mg/mL, respectively) was significantly increased by 2.77, 2.70, 4.34 times, respectively. Besides, live/dead staining and scanning electron microscope (SEM) revealed that the 2D cultured cells shrank and ruptured after crocin treatment, and the number of living cells was considerably reduced; the size of the cell colonies in the 3D microgel beads decreased.

Inhibitory Effect of Crocin Against Gastric Carcinoma via Regulating TPM4 Gene

Background

Gastric cancer (GC) is one of the most common malignant tumors and the second most frequent cause of cancer death worldwide. Crocin is a kind of bioactive constituent found in the stigmas of saffron, which has shown various pharmacological activities.

Methods

In this study, we investigated the inhibitory effect of crocin on gastric cancer AGS cells proliferation and explored the underlying mechanism. A series of methods were used including cell counting kit assay, gene microarray analysis, qRT-PCR, Celigo image cytometry, cell clone formation assay, Western blot, and cell xenograft growth in vivo.

Results

The results indicated that crocin inhibited AGS cells proliferation and promoted cell apoptosis. Further studies suggested that crocin decreased a series of genes expression, among which TPM4 gene downregulation inhibited the tumor cells proliferation and tumor growth in mice, and overexpression of TPM4 gene abolishes the inhibitory effect of crocin. Further study using microarray analysis suggested that knocking down of TPM4 altered genes related to the proliferation and apoptosis of cells.

Discussion

Crocin could inhibit the gastric cancer cells AGS cells proliferation by regulating TPM4 gene expression, and TPM4 may be a promising therapeutic target for GC treatment.

Crocin reverses 1-methyl-3-nitroso-1-nitroguanidine (MNNG)-induced malignant transformation in GES-1 cells through the Nrf2/Hippo signaling pathway

BACKGROUND

Crocin, an active constituent of saffron, has anticancer activity. In this study, we investigated the relationship of Crocin with human gastric epithelial cells induced by 1-methyl-3-nitroso-1-nitroguanidine (MNNG), and explored the underlying mechanism.

METHODS

In vivo, the animal growth and atypical hyperplasia were observed in Sprague-Dawley rats. A cell model was established by treating the human gastric mucosa epithelial cell line GES-1 with MNNG. The effects of Crocin on proliferation, cell cycle, apoptosis, and epithelial-mesenchymal transition (EMT) in GES-1 cells were analyzed using Cell Counting Kit-8, colony formation, flow cytometry, and Transwell assay, respectively. Western blot was used to explore the potential mechanism..

RESULTS

The gastric mucosa of animal model deteriorated obviously, the weight growth rate slowed down, and the atypical hyperplasia of gastric mucosa increased. The GES-1 cells had characteristics of malignant cells such as proliferation, apoptosis, and metastasis ability. It was found that Crocin suppressed the cell proliferation, increased apoptosis, and blocked the cycle arrest in G0/G1 phase simultaneously. Furthermore, Crocin negatively regulated the invasion ability of MNNG-treated GES-1 cells and EMT process. Crocin also increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), decreased TAZ in MNNG-treated GES-1 cells. Interestingly, Crocin regulated the expression of TAZ and yes-associated protein (YAP) by increasing Nrf2 level, as well as their upstream targets, mercaptopyruvate sulfurtransferase (MST) and large tumor suppressor (LATS).

CONCLUSIONS

Crocin protected against MNNG-induced malignant transformation through the Nrf2/Hippo signaling pathway, which might be a drug candidate for clinical gastric cancer management.

Genome-wide association study of prevalent and persistent cervical high-risk human papillomavirus (HPV) infection

Background

Genetic factors may influence the susceptibility to high-risk (hr) human papillomavirus (HPV) infection and persistence. We conducted the first genome-wide association study (GWAS) to identify variants associated with cervical hrHPV infection and persistence.

Methods

Participants were 517 Nigerian women evaluated at baseline and 6 months follow-up visits for HPV. HPV was characterized using SPF₁₀/LiPA₂₅. hrHPV infection was positive if at least one carcinogenic HPV genotype was detected in a sample provided at the baseline visit and persistent if at least one carcinogenic HPV genotype was detected in each of the samples provided at the baseline and follow-up visits. Genotyping was done using the Illumina Multi-Ethnic Genotyping Array (MEGA) and imputation was done using the African Genome Resources Haplotype Reference Panel. Association analysis was done for hrHPV infection (125 cases/392 controls) and for persistent hrHPV infection (51 cases/355 controls) under additive genetic models adjusted for age, HIV status and the first principal component (PC) of the genotypes.

Results

The mean (±SD) age of the study participants was 38 (±8) years, 48% were HIV negative, 24% were hrHPV positive and 10% had persistent hrHPV infections. No single variant reached genome-wide significance (p < 5 X 10^− 8). The top three variants associated with hrHPV infections were intronic variants clustered in KLF12 (all OR: 7.06, p = 1.43 × 10^− 6). The top variants associated with cervical hrHPV persistence were in DAP (OR: 6.86, p = 7.15 × 10^− 8), NR5A2 (OR: 3.65, p = 2.03 × 10^− 7) and MIR365–2 (OR: 7.71, p = 2.63 × 10^− 7) gene regions.

Conclusions

This exploratory GWAS yielded suggestive candidate risk loci for cervical hrHPV infection and persistence. The identified loci have biological annotation and functional data supporting their role in hrHPV infection and persistence. Given our limited sample size, larger discovery and replication studies are warranted to further characterize the reported associations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12881-020-01156-1.

Chemo-preventive effect of crocin against experimentally-induced hepatocarcinogenesis via regulation of apoptotic and Nrf2 signaling pathways

The results of the current study investigated the chemo-preventive effect of crocin against hepatocarcinogenesis in rats with particular focus on the evaluation of the modulatory impact of crocin on apoptotic and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. Thioacetamide (TAA) (200 mg/kg, I.P.) was used for experimental induction of hepatocarcinogenesis in rats. Crocin administration significantly attenuated TAA-induced cancerous lesions with concomitant attenuation of impaired liver functions. This was associated with significant enhancement in hepatic Nrf2 and heme oxygenase-1 (HO-1) expression with parallel suppression in Keap-1 expression. Inline, crocin induced a significant improvement in hepatic oxidative status with enhanced antioxidant batteries. Crocin administration significantly suppressed the hepatic content of c-Jun N-terminal kinase (c-JNK) with significant upregulation in TNF-related apoptosis-inducing ligand (TRAIL) and caspase-8 protein expression as well as p53 gene expression; biomarkers of apoptosis. Moreover, hepatic expression of the apoptotic BAX significantly increased and the anti-apoptotic Bcl-2 significantly decreased in the liver specimen; biomarkers of intrinsic apoptosis. In conclusion; crocin attenuates experimentally induced hepato-carcinogenesis via modulation of oxidative/apoptotic signaling. Namely, crocin induced hepatic expression of Nrf2 with downstream modulation of endogenous HO-1 and Keap-1 signaling with modulation of various key players of apoptosis including; c-JNK, p53, TRAIL, caspase-8, BAX, and Bcl-2.

Comparative assessment of immunomodulatory, proliferative, and antioxidant activities of crocin and crocetin on mesenchymal stem cells

Saffron (Crocus sativus L) is a well-known spice with active pharmacologic components including crocin, crocetin, safranal, and picrocrocin. Similar to crocin/crocetin, mesenchymal stem cells (MSCs) have been shown to display immunomodulatory and antioxidant properties, which could be beneficial in treatment of various diseases. In the current study, we have evaluated the effects of crocin and crocetin on the functions of MSCs. We used the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay to evaluate MSCs proliferation, and flow cytometry assay to measure the percentage of apoptotic MSCs and Tregs populations. Furthermore, we used the real-time polymerase chain reaction method to quantify messenger RNA (mRNA) expression of inflammatory and anti-inflammatory cytokines. Antioxidant assay was employed to quantify antioxidant parameters including nitric oxide and malondialdehyde levels besides superoxide dismutase activity. Our findings indicated that both crocin and crocetin at low concentrations (2.5 and 5 µM) exhibited significant effects on increasing MSCs viability and on protecting them against apoptosis-induced death. Furthermore, crocin and crocetin at low concentrations (2.5 and 5 µM) displayed a better antioxidant function. Moreover, increased Treg population was observed at lower doses. In addition, crocin/crocetin at low concentrations caused an elevation in mRNA expression of anti-inflammatory cytokines (transforming growth factor-β, interleukin-10 [IL-10], and IL-4), while at higher doses (25 and 50 µM) they led to lowering inflammatory cytokines (IL-1β, IL-6, IL-17, and interferon gamma). Altogether, both crocin and crocetin at lower concentrations exhibited more efficacies on MSCs with a better effect toward crocin. It seems that crocin and crocetin may be considered as complementary treatments for the patients who undergo MSCs transplantation.

Crocin induces autophagic cell death and inhibits cell invasion of cervical cancer SiHa cells through activation of PI3K/AKT

Background

Cervical cancer is a prevalent tumor mainly induced by Human Papilloma Virus (HPV). Autophagy was inactivated with HPV to promote cancer progression. Here we explored the effects of crocin on cervical cancer cells, mainly on autophagy and apoptosis.

Methods

SiHa cells were treated with crocin, and proliferation, metastases, apoptosis and autophagy were measured using a CCK-8 assay, transwell migration assay, flow cytometry and immunofluorescence. Protein levels were measured using western blotting. The antitumor effects of crocin were validated in female BALB/c nude mice injected with SiHa cells.

Results

The result showed that 2, 4, 8 and 16 mM of crocin significantly reduced the viability of SiHa cells within 24 h. Subsequently, 0, 1, 2 and 4 mM crocin concentrations were used in later experiments. Treatment with crocin reduced invasive cells, while increasing autophagic and apoptotic cells dose-dependently. The enhanced apoptosis and autophagy were partly validated by an increase in cleaved caspase-3/caspase-3, cleaved caspase-9/caspase9, LC3B II/I, Beclin1 and ATG7. AMPK and mTOR were inactivated with crocin treatment, while PI3K was activated. These results indicated that crocin might promote autophagy and apoptosis by inactivating AMPK and mTOR signaling. Tumor progression was inhibited in mice treated with 50 mg/kg/d of crocin, which was demonstrated by smaller tumor volumes, less VEGF expression, more intense caspase-3 staining and increased LC3B II/I in the tumor tissues.

Conclusions

Crocin inhibited the progression of cervical cancer in vitro and in vivo, possibly through inactivation of AMPK and mTOR, inhibition of proliferation and invasion, and promotion of autophagy and apoptosis. These results support the potential therapeutic value of crocin in treating cervical cancer.

Carotenoids in Cancer Apoptosis-The Road from Bench to Bedside and Back

An incidence and mortality of cancer are rapidly growing worldwide, especially due to heterogeneous character of the disease that is associated with irreversible impairment of cellular homeostasis and function. Targeting apoptosis, one of cancer hallmarks, represents a potent cancer treatment strategy. Carotenoids are phytochemicals represented by carotenes, xanthophylls, and derived compounds such as apocarotenoids that demonstrate a broad spectrum of anti-cancer effects involving pro-apoptotic signaling through extrinsic and intrinsic pathways. As demonstrated in preclinical oncology research, the apoptotic modulation is performed at post-genomic levels. Further, carotenoids demonstrate additive/synergistic action in combination with conventional oncostatic agents. In addition, a sensitization of tumor cells to anti-cancer conventional treatment can be achieved by carotenoids. The disadvantage of anti-cancer application of carotenoids is associated with their low solubility and, therefore, poor bioavailability. However, this deficiency can be improved by using nanotechnological approaches, solid dispersions, microemulsions or biofortification that significantly increase the anti-cancer and pro-apoptotic efficacy of carotenoids. Only limited number of studies dealing with apoptotic potential of carotenoids has been published in clinical sphere. Pro-apoptotic effects of carotenoids should be beneficial for individuals at high risk of cancer development. The article considers the utility of carotenoids in the framework of 3P medicine.

Anticancer and apoptotic activities of parthenolide in combination with epirubicin in mda-mb-468 breast cancer cells

Breast cancer is the most common malignancy in women worldwide. Unfortunately, current therapeutic methods are not completely efficient. Hence, combination therapy with medicinal plants has attracted several kinds of research. In the current study, we aimed to investigate the apoptotic and anti-cancer effect of Parthenolide in combination with Epirubicin in the MDA-MB-468 breast cancer cell line. In this study,  the anti-proliferative and pro-apoptotic effect of Parthenolide in combination with Epirubicin and without it, in the MDA-MB-468 cell line have been assessed by MTT test, Hoescht staining and flow cytometry methods. Our outcomes showed that Parthenolide treatment in the present of Epirubicin led to a decrease in the minimum toxic concentration of Parthenolide and Epirubicin in comparison with individual treatments. Then, to achieve a likely molecular mechanism of mentioned drugs Bax and Bcl2 expression level evaluated by Real-time PCR and subsequently, Western blotting has been estimated the protein level of Caspase 3. Our data indicated that the treatment of cells with Parthenolide led to up-regulation of Bax and downregulation of Bcl2 at mRNA level. Moreover, Parthenolide treatment led to the obvious alternation of Caspase3 protein level. These results indicated that Parthenolide in combination with Epirubicin have significant cytotoxicity due to targeting the main regulators of apoptosis. Hence, according to lack of cytotoxicity of Parthenolide on normal cells that lead to reduction of drug side effects, it could be suggested as an adjuvant therapy with Epirubicin after complementary research on animal model and clinical trial.

Crocin Increases Gastric Cancer Cells' Sensitivity to Doxorubicin

Background:

Crocin is one of the substantial constituents of saffron extract. It has multiple clinical effects including anti-cancer effects. The development of the multidrug resistance (MDR) phenotype is one of the principal causes of cancer chemotherapy failure. The multidrug resistance protein 1 (MDR1) is one of the MDR-related protein and is often overexpressed in different cancers. In the present study, we aimed to evaluate the influence of crocin on the expression and function of MDR1 protein in EPG85-257 and EPG85-257RDB gastric cancer cell lines.

Methods:

The cytotoxicity effect of crocin was evaluated by the MTT assay. The impacts of crocin on the expression and function of MDR1 were assessed by Real-time RT-PCR and MTT assay, respectively.

Results:

The results demonstrated that crocin decreased cell viability in a dose-dependent manner with higher intensity on the EPG85-257 than the EPG85-257RDB cells. Crocin did not make any significant changes in the MDR1 gene expression level in EPG85-257 and EPG85-257RDB cell lines. In contrast, crocin increased doxorubicin cytotoxicity in drug-resistant cells, which might be induced by reduced MDR1 activity.

Conclusion:

In summary, although crocin did not affect mRNA expression of MDR1, results of MTT assay suggest that it might inhibit the MDR1 function.

Tambuwala M. Dietary Crocin is Protective in Pancreatic Cancer while Reducing Radiation-Induced Hepatic Oxidative Damage

Pancreatic cancer is one of the fatal causes of global cancer-related deaths. Although surgery and chemotherapy are standard treatment options, post-treatment outcomes often end in a poor prognosis. In the present study, we investigated anti-pancreatic cancer and amelioration of radiation-induced oxidative damage by crocin. Crocin is a carotenoid isolated from the dietary herb saffron, a prospect for novel leads as an anti-cancer agent. Crocin significantly reduced cell viability of BXPC3 and Capan-2 by triggering caspase signaling via the downregulation of Bcl-2. It modulated the expression of cell cycle signaling proteins P53, P21, P27, CDK2, c-MYC, Cyt-c and P38. Concomitantly, crocin treatment-induced apoptosis by inducing the release of cytochrome c from mitochondria to cytosol. Microarray analysis of the expression signature of genes induced by crocin showed a substantial number of genes involved in cell signaling pathways and checkpoints (723) are significantly affected by crocin. In mice bearing pancreatic tumors, crocin significantly reduced tumor burden without a change in body weight. Additionally, it showed significant protection against radiation-induced hepatic oxidative damage, reduced the levels of hepatic toxicity and preserved liver morphology. These findings indicate that crocin has a potential role in the treatment, prevention and management of pancreatic cancer.

Dietary carotenoids in cancer chemoprevention and chemotherapy: A review of emerging evidence

In recent years, natural products have reemerged as biotherapeutic options, with several dietary carotenoids, viz. astaxanthin, fucoxanthin, siphonaxanthin, β-cryptoxanthin, α-carotene, β-carotene, and lycopene, developing as potential candidates for chemoprevention and chemotherapeutics of breast, colorectal, lung, and prostate cancers. The potent cytotoxic and antiproliferative effects of carotenoids against various cancer cells are mediated by a wide range of molecular mechanisms modulating oxidative stress and redox balance, mitogen-activated protein kinases (MAPK) and other cellular signaling proteins, transcription factors, caspase cascade pathways of apoptosis, cell cycle progression and proliferation, angiogenesis, metastasis, gap junction intercellular communication (GJIC), and multidrug resistance (MDR). This review discusses recent evidence demonstrating the crucial roles of carotenoids in these cellular and molecular events of cancer cell cytotoxicity. In addition, recent case-control and cohort studies are discussed to support the potential role of carotenoids in cancer prevention and therapy.

Antioxidant, Antimicrobial, Antidiabetic and Cytotoxic Activity of Crocus sativus L. Petals

The purpose of this research is to examine in vitro antioxidant, antimicrobial, antidiabetic and cytotoxic efficacy of different extracts of Crocus sativus L. petals. Antioxidant activity of extracts was assessed by DPPH and ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) assay. Among all extracts, ethanol (SPE) had the maximum radical scavenging activity with IC50 values 86.63 ± 7.53 μg/mL. The antimicrobial activity was determined by the evaluation of the minimum inhibitory concentration using the agar well plate procedure. The most effective extract was SPE with a minimum inhibitory concentration varying between 500 µg/mL, 250 µg/mL, 125 µg/mL, 62.5 µg/mL, 31.25 µg/mL, 15.63 µg/mL. Cytotoxic activity was tested against MDA-MB-231 cell lines using the MTT method whereas, antidiabetic activity was evaluated using an alpha-glucosidase inhibition assay. All extracts were found to have significant antidiabetic activity.

Crocins: The Active Constituents of Crocus Sativus L. Stigmas, Exert Significant Cytotoxicity on Tumor Cells In Vitro

Background::

Tumors of the childhood are considered to be grave and devastating pathologies, with high mortality rates. Current therapeutic options like cytotoxic drugs and radiotherapy target both healthy and malignant cells, thus resulting in long-term neurological and intellectual sequelae and endocrinological disorders.

Objectives::

In this study, we focused on the anticancer potency of crocins, the main constituents of Crocus sativus L, stigmas. Crocins were first extracted using organic solvents from the dried stigmas and then were identified using the HPLC analysis.

Materials and Methods::

TE-671 cells were treated with the extract of crocins using a range of concentrations between 0.25-mg/ mL and 16 mg/mL. Viability of the cells was measured at 24h, 48h, 72h and 96h. In addition, we have examined the expression levels of the p53 gene using Real-Time Reverse Transcription PCR.

Results::

Results showed that crocins exerted significant cytotoxic and anti-proliferative effects in a concentration and time - dependent-manner on TE-671 cells. Furthermore, p53 manifested similar expression pattern as the anti-proliferative effect of crocin.

Conclusion::

Our data demonstrate that crocins could be a novel promising agent for the improvement of tumor treatment.

Crocin inhibits the migration, invasion, and epithelial-mesenchymal transition of gastric cancer cells via miR-320/KLF5/HIF-1α signaling

The biological activities of crocin, one of the main bioactive compounds of saffron, include anti-inflammatory, antioxidant, antidepressant, and anticancer effects. Crocin has been shown to trigger the apoptosis of gastric cancer cells, but its effect on the metastasis of gastric cancer cells remains unclear. Krüppel-like factor 5 (KLF5) and hypoxia-inducible factor-1α (HIF-1α) are important transcription factors in the development of gastric cancer. KLF5 and HIF-1α expression were analyzed in gastric cancer tissues and cells. Following exposure to crocin, AGS and HGC-27 gastric cancer cells were assessed with regard to migration, invasion, and epithelial-mesenchymal transition (EMT) as well as the expression of KLF5, HIF-1α, and microRNA-320 (miR-320). The miR-320/KLF5/HIF-1α signaling pathway became the focus for further investigation of the mechanism of crocin in gastric cancer cell migration, invasion, and EMT. KLF5 and HIF-1α expression were elevated in gastric cancer tissues and cells, and KLF5 expression was positively correlated with the HIF-1α level in gastric cancer tissues. Crocin was associated with reduced expression of KLF5 and HIF-1α, whereas miR-320 expression was increased. Crocin also inhibited the migration, invasion, and EMT of gastric cancer cells. Upregulation of KLF5 attenuated crocin's function and elevated HIF-1α expression. Dual-luciferase reporter assay demonstrated that KLF5 was a target gene of miR-320. Crocin modulated KLF5 expression via elevation of miR-320 expression. In conclusion, crocin inhibits the EMT, migration, and invasion of gastric cancer cells, and this activity is mediated through miR-320/KLF5/HIF-1α signaling.

Crocin inhibits proliferation and induces apoptosis through suppressing MYCN expression in retinoblastoma

The pathogenetic mechanisms of retinoblastoma are still not yet fully elucidated, putting limits to efficacious treatment. Crocin is the main component of saffron, which exhibits significant antitumorigenic properties. The aim of this paper is to investigate the effect of crocin on retinoblastoma. The effects of crocin on the proliferation of human retinoblastoma cells were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell number assay, and colony formation assay. Cell apoptosis induced by crocin was measured by flow cytometry analysis. Cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 were tested by western blot analysis. The expression levels of MYCN were assessed by western blot and quantitative polymerase chain reaction and the stability of MYCN messenger RNA was determined by in vitro RNA degradation assays. We found that crocin significantly inhibited the cell proliferation and clonogenicity and induced cell apoptosis in Y79 and WERI-RB-1 cells. In addition, crocin treatment significantly reduced the expression and the stability of MYCN. Besides, overexpression of MYCN rescued the inhibitory effect of crocin in Y79 cells. Our findings suggest that crocin exhibits antitumorigenic effects in human retinoblastoma cell lines through a MYCN-dependent manner, which may provide guidance to logical therapeutic designs in prevention and treatment of retinoblastoma.

Crocin induces autophagic apoptosis in hepatocellular carcinoma by inhibiting Akt/mTOR activity

Background

Autophagy induction is a common mechanism for antitumor chemicals in induction of cancer cell death. However, the role of autophagy in crocin-induced apoptosis is barely studied in hepatocellular carcinoma (HCC).

Materials and methods

The influence of crocin on growth, apoptosis, and autophagy and its mutual relations were analyzed by Cell Counting Kit-8 assay, flow cytometer, EGFP-LC3 puncta analysis, and Western blot in HCC cells. The activities of Akt/mTOR axis and its roles in autophagy regulation were also detected by Western blot in HCC cells treated with crocin. Finally, the roles of Akt/mTOR axis in crocin-induced autophagic apoptosis were analyzed by Western blot and flow cytometer in HCC cells.

Results

The results showed that crocin can induce growth inhibition in a does- and time-dependent pattern by apoptosis. Increased LC3 puncta and upregulated LC3-II accumulation was observed as early as at 6 hours in HepG2 and HCCLM3 cells treated with 3 mg/mL crocin. Moreover, apoptosis analysis using flow cytometer and cleaved poly (ADP-ribose) polymerase detection revealed that autophagy initiation was prior to apoptosis activation in HCC cells treated with crocin. When autophagy was blocked with 3-methyladenine, crocin-induced apoptosis was inhibited in HCC cells. Furthermore, crocin treatment constrained the activities of key proteins in Akt/mTOR signaling, such as p-Akt (S473), p-mTOR (S2448), and p-p70S6K (T389), suggesting that crocin could induce autophagic apoptosis in HCC cells in an Akt/mTOR-dependent mechanism. Indeed, when autophagy was suppressed by forced expression of Akt, the crocin-induced apoptosis was also impaired in HCC cells.

Conclusion

The results suggested that crocin could induce autophagic apoptosis in HCC cells by inhibiting Akt/mTOR activity. This study originally revealed that autophagic apoptosis is a novel cytotoxic function of crocin, which lays the theoretical foundation for clinical application of crocin in HCC.

A comprehensive review of the pharmacological potential of Crocus sativus and its bioactive apocarotenoids

Crocus sativus is an herbaceous plant that belongs to family Iridaceae. It is commonly known as saffron and has been used for medicinal purposes since many centuries in India and other parts of the world. Saffron of commercial importance comprises of dried stigmas of the plant and is rich in flavonoids, vitamins, and carotenoids. Carotenoids represent the main components of saffron and their cleavage results in the formation of apocarotenoids such as crocin, picrocrocin, and safranal. Studies conducted during the past two decades have revealed the immense therapeutic potential of saffron. Most of the therapeutic properties are due to the presence of unique apocarotenoids having strong free radical scavenging activity. The mode of action of these apocarotenoids could be: modulatory effects on detoxifying enzymes involved in combating oxidative stress, decreasing telomerase activity, increased the proapoptotic effect, inhibition of DNA, RNA and protein synthesis, and by a strong binding capacity of crocetin with tRNA. The present review focuses on the therapeutic role of saffron and its bio oxidative cleavage products and also highlights the possible molecular mechanism of action. The findings reported in this review describes the wide range of applications of saffron and attributes its free radical scavenging nature the main property which makes this spice a potent chemotherapeutic agent for the treatment of various diseases.