Natural Products in Preventing Tumor Drug Resistance and Related Signaling Pathways.

Drug resistance is still an obstacle in cancer therapy, leading to the failure of tumor treatment. The emergence of tumor drug resistance has always been a main concern of oncologists. Therefore, overcoming tumor drug resistance and looking for new strategies for tumor treatment is a major focus in the field of tumor research. Natural products serve as effective substances against drug resistance because of their diverse chemical structures and pharmacological effects. We reviewed the signaling pathways involved in the development of tumor drug resistance, including Epidermal growth factor receptor (EGFR), Renin-angiotensin system (Ras), Phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt), Wnt, Notch, Transforming growth factor-beta (TGF-ß), and their specific signaling pathway inhibitors derived from natural products. This can provide new ideas for the prevention of drug resistance in cancer therapy.

Quantitative proteomics analysis of differentially expressed proteins induced by astragaloside IV in cervical cancer cell invasion.

BACKGROUND: Cervical cancer remains the second leading cause of mortality in women in developing countries. While surgery, chemotherapy, radiotherapy, and vaccine therapy are being applied for its treatment, individually or in combination, the survival rate in advanced cervical cancer patients is still very low. Traditional Chinese medicine has been found to be effective in the treatment of cervical cancer. Astragaloside IV (AS-IV), a compound belonging to Astragalus polysaccharides, shows anticancer activity through several cell signaling pathways. However, the detailed molecular mechanism governing the anticancer activity of AS-IV remains unknown. MATERIAL AND METHODS: In our study, we performed tumor xenograft analysis, transwell cell migration and invasion assay, Western blot analysis, and iTRAQ combination by parallel reaction monitoring (PRM) analysis to study the molecular mechanism of AS-IV in the suppression of cervical cancer cell invasion. RESULTS: Our results showed that AS-IV suppressed cervical cancer cell invasion and induced autophagy in them, with the tumor growth curve increasing slowly. We also identified 32 proteins that were differentially expressed in the SiHa cells when treated with AS-IV, with 16 of them involved in the upregulation and 16 in the downregulation of these cells. These differentially expressed proteins, which were predominantly actin-myosin complexes, controlled cell proliferation and cell development by steroid binding and altering the composition of the cell cytoskeleton. DCP1A and TMSB4X, the two proteins regulating autophagy, increased in cervical cancer cells when treated with AS-IV. CONCLUSIONS: We conclude that AS-IV could inhibit cervical cancer invasion by inducing autophagy in cervical cancer cells. Since iTRAQ combination by PRM has been observed to be useful in identifying macromolecular target compounds, it may be considered as a novel strategy in the screening of anticancer compounds used in the treatment of cervical cancer.

TCF7L1 indicates prognosis and promotes proliferation through activation of Keap1/NRF2 in gastric cancer.

Gastric cancer is one of the most common cancers worldwide and is the third leading cause of cancer-related deaths globally. Although significant progress has been made in the diagnosis and treatment for the cancer, less improvement has been made in overall survival rate. Thus, there is an urgent need for a better understanding of the biological aspects of the cancer. The transcription factor transcription factor 7-like 1 (TCF7L1) is an embryonic stem cell signature gene that is upregulated in multiple aggressive cancer types, but its role in gastric cancer has seldom been discussed. In the present study, by using the Cancer Genome Atlas dataset analysis, we demonstrated that patients with higher expression of TCF7L1 could be used to reflect prognosis. An examination of the mechanisms demonstrated that TCF7L1 could positively regulate antioxidant response in gastric cancer cells by positively regulating Keap1/NRF2 [Kelch-like ECH-associated protein 1/nuclear factor (erythroid-derived 2)-like 2] pathway. Collectively, our data demonstrated that TCF7L1 is a novel marker for predicting overall survival of gastric cancer and provided the possible underlying molecular mechanism.

MiR-133b-5p regulates the expression of the heat shock protein 70 during rat neuronal cell apoptosis induced by the gp120 V3 loop peptide.

Neuronal cell dysfunction and apoptosis, the main causes of HIV-associated dementia, and its underlying mechanism are important unsolved health problems. Many research reports suggest that miRNAs regulate HIV-1-induced apoptosis. We used the HIV-1 gp120 V3 Loop peptide to induce primary rat cortical neurons apoptosis. Next, we used a microRNA microarray to identify the significant changes of miRNA in the rat cortical neurons treated with the gp120 V3 loop peptide. We used western blot and real-time PCR to measure the regulation of heat shock protein 70 by rno-miR-133b-5p. In response to the gp120 V3 loop peptide treatment, rat cortical neurons exhibited 11 up-regulated and 21 down-regulated miRNAs. We further examined miR-133b-5p, a microRNA that was up-regulated more than 118-fold. In addition, both HSP70 mRNA and protein expression were dose-dependent in rats cortical neurons treated with gp120 V3 loop peptide for 48 hr. MiR-133b-5p could regulate heat shock protein 70 (HSP70) at both transcription and translation levels. Rno-miR-133b-5p might be less significant for the gp120 V3 loop peptide induced neuron apoptosis. Thus, we discovered a potential new target for the regulation of HIV-1 gp120- induced apoptosis.

Prognostic factors and multidisciplinary treatment modalities for brain metastases from colorectal cancer: analysis of 93 patients.

BACKGROUND: The purpose of this study was to review patient characteristics and evaluate the potential factors affecting prognosis in cases of brain metastasis (BM) from colorectal cancer (CRC). METHODS: We retrospectively reviewed 93 cases of BM from CRC in our hospital. Patient demographics, neurologic symptoms, and location and number of BMs were recorded. Factors analyzed included: age; sex; Karnofsky performance score; number of BMs; presence of extracranial metastases; dimensions; location of tumors; treatment modalities. RESULTS: The overall 1- and 2-year survival rates were 27.7 and 9.9%. On multivariate analysis, the number of BMs, extracranial metastases and the initial treatment modalities were found to be independent prognostic factors for overall survival. Patients treated with surgical resection followed by WBRT or SRS had an improved prognosis relative to those treated with surgery alone (P=0.02 and P=0.02, respectively). No significance difference in survival rate was found between patients treated with SRS alone or SRS plus WBRT (P=0.11). CONCLUSIONS: Surgical resection of BMs from CRC in selected patients may help prolong survival. Additional radiotherapy following surgery is valuable in improving prognosis. Extracranial metastasis, multiple BM lesions and initial non operation can be considered as independent factors associated with poor prognosis.

Curcumin Increases HSP70 Expression in Primary Rat Cortical Neuronal Apoptosis Induced by gp120 V3 Loop Peptide.

Neuronal cell dysfunction and apoptosis are the main causes of the invasion of the central nervous system by human immunodeficiency virus type 1 (HIV-1), although the underlying mechanism has not been well understood. Recent research has shown that curcumin might play an important role in regulating HIV-1 development. Heat shock protein 70 (HSP70), a protein induced by heat, was reported to inhibit apoptosis through various cell signaling pathways in brain. Overexpression of HSP70 could effectively protected neurons in many animal and cellular models of dementia. In the present study, the expression of HSP70 in the gp120 V3 loop peptide-induced neuronal apoptosis was investigated. Our results demonstrated that gp120 V3 loop peptide could induce primary rat cortical neuronal apoptosis. We also found that curcumin could increase HSP70 expression. In addition, the expression level of both HSP70 mRNA and HSP70 protein were dependent on the curcumin dose in the rat cortical neurons. Curcumin could improve HSP70 expression in gp120 V3 loop peptide-induced primary rat cortical neuronal apoptosis. In general, our results indicated that curcumin played an important role in the gp120 V3 loop peptide induced neuronal apoptosis by regulating HSP70.

Modelling and monitoring social network change based on exponential random graph models.

This paper aims to detect anomalous changes in social network structure in real time and to offer early warnings by phase II monitoring social networks. First, the exponential random graph model is used to model social networks. Then, a test and online monitoring technique of the exponential random graph model is developed based on the split likelihood-ratio test after determining the model and its parameters for a specific data set. This proposed approach uses pseudo-maximum likelihood estimation and likelihood ratio to construct the test statistics, avoiding the several steps of discovering Monte Carlo Markov Chain maximum likelihood estimation through an iterative method. A bisection algorithm for the control limit is given. Simulations on three data sets Flobusiness, Kapferer and Faux.mesa.high are presented to study the performance of the procedure. Different change points and shift sizes are compared to see how they affect the average run length. A real application example on the MIT reality mining social proximity network is used to illustrate the proposed modelling and online monitoring methods.

Potassium channels, tumorigenesis and targeted drugs.

Potassium channels play an important role in human physiological function. Recently, various molecular mechanisms have implicated abnormal functioning of potassium channels in the proliferation, migration, invasion, apoptosis, and cancer stem cell phenotype formation. Potassium channels also mediate the association of tumor cells with the tumor microenvironment. Meanwhile, potassium channels are important targets for cancer chemotherapy. A variety of drugs exert anti-cancer effects by modulating potassium channels in tumor cells. Therefore, there is a need to understand how potassium channels participate in tumor development and progression, which could reveal new, novel targets for cancer diagnosis and treatment. This review summarizes the roles of voltage-gated potassium channels, calcium-activated potassium channels, inwardly rectifying potassium channels, and two-pore domain potassium channels in tumorigenesis and the underlying mechanism of potassium channel-targeted drugs. Therefore, the study lays the foundation for rational and effective drug design and individualized clinical therapeutics.

Hemoporfin-mediated photodynamic therapy for the treatment of port-wine stain: A multicenter, retrospective study.

BACKGROUND: Hemoporfin-mediated photodynamic therapy (Hemoporfin-PDT) has been approved for port-wine stain (PWS) in China in 2017. This study evaluated the efficacy and safety of Hemoporfin-PDT for PWS in a real life setting and investigated factors that influence the efficacy. METHODS: A multicenter retrospective study included patients with PWS who underwent Hemoporfin-PDT in 29 hospitals across China and completed at least two months of follow-up. The efficacy was evaluated based on patien photographs. RESULTS: A total of 1679 patients were included. After the first and second sessions of Hemoporfin-PDT, 63.5 and 75.3% of patients responded, respectively. The response rate of purple-type PWS was significantly lower than that of pink-type PWS (OR: 0.71, 95% CI: 0.54-0.94, P < 0.05), and there was no significant difference between thick- and pink-type (OR: 0.72, 95% CI: 0.42-1.22, P > 0.05). The response rate of PWS on the limbs was significantly lower than that on the mid-face (OR: 0.35, 95% CI: 0.23-0.53, P < 0.0001), while no significant difference was observed between PWS on the peripheral part of the face, neck or other parts of the body and PWS on the mid-face (P > 0.05). The response rate was lower in male patients with an age > 3 years or ≤ 6 years (P < 0.05). Previous treatment history did not affect the efficacy (P > 0.05). Hemoporfin-PDT was well tolerated. CONCLUSION: Patients with PWS have a good response and good tolerance to Hemoporfin-PDT.

HIV-infection resistance in PMBC-derived dendritic cells modified with recombinant virus.

This study aimed to identify the characteristics of recombinant-adenovirus-modified PBMC-derived dendritic cells and their resistance to HIV-1 infection by integrating the CCR5∆32, CCR5siRNA, HIV-1 pol and HIV-1 int genes into a recombinant adenovirus vector using the AdEasy system. Dendritic cells (DCs) were isolated from human PBMCs from blood of healthy donors. The expression of CCR5∆32, CCR5, CXCR4 and HIV-1 p24 in PBMCs or modified cells was measured by western blot, p24 expression in cell lysates was measured by ELISA, and HIV-1 entry was measured by ß-galactosidase assay. Furthermore, T-cell immunity induced by the recombinant adenovirus was measured by ELISPOT assay. After the cells were modified by Ad-R5∆32siRNA, the expression of CCR5∆32 increased, while the expression of CCR5 and CXCR4 decreased. There was no adverse effect of adenoviral gene transfer on DC development. CD83 expression on the surface of mature DCs did not change after gene transfer. The expression of p24 remained at low levels in modified cells when challenged by HIV-1. The modified cells showed resistance to HIV-1 infection. Results indicated that recombinant-adenovirus-modified cells demonstrated good resistance to HIV-1 infection. Modification of HSC-derived immune cells, such as DCs, may be a potent strategy to resist HIV-1 infection.

Role of microbes in colorectal cancer therapy: Cross-talk between the microbiome and tumor microenvironment.

The human gut microbiota is associated with the development and progression of colorectal cancer, and manipulation of the gut microbiota is a novel strategy for the prevention and treatment of colorectal cancer. Some bacteria have antitumor activity against colorectal cancer, where specific bacteria can improve the tumor microenvironment, activate immune cells including dendritic cells, helper T cells, natural killer cells, and cytotoxic T cells, and upregulate the secretion of pro-tumor immune cytokines such as interleukin-2 and interferon. In this paper, we summarize some bacteria with potential benefits in colorectal cancer and describe their roles in the tumor microenvironment, demonstrate the application of gut microbes in combination with immunosuppressive agents, and provide suggestions for further experimental studies and clinical practice applications.

N6-methyladenosine-modified long non-coding RNA AGAP2-AS1 promotes psoriasis pathogenesis via miR-424-5p/AKT3 axis.

BACKGROUND: Psoriasis is a chronic, complicated, and recurrent inflammatory skin disease. However, the precise molecular mechanisms remain largely elusive and the present treatment is unsatisfactory. OBJECTIVE: This study aimed to unravel the functions of long noncoding RNA (lncRNA) AGAP2-AS1 and its biological mechanism in psoriasis pathogenesis, hinting for the new therapeutic targets in psoriasis. METHODS: The expression of AGAP2-AS1 in the skin tissue of psoriasis patients and healthy controls were detected by qRT-PCR and RNAscope®. Cell Counting Kit­8 (CCK8) and clone formation assays were utilized to assess proliferation. Methylated RNA immunoprecipitation (MeRIP) was performed to detect the N6-methyladenosine (m6A) modification. RNA immunoprecipitation (RIP) was used to detect the interaction of AGAP2-AS1 with YTH domain family 2(YTHDF2). The relationships among AGAP2-AS1, miR-424-5p and AKT3 were examined by dual-luciferase reporter assay and RIP assay. RESULTS: We found that AGAP2-AS1 level was upregulated in the skin tissue of psoriasis patients than that of healthy controls and AGAP2-AS1 could promote proliferation and inhibit apoptosis of keratinocytes. Methyltransferase like 3(METTL3)-mediated m6A modification suppressed the expression of AGAP2-AS1 via YTHDF2-dependent AGAP2-AS1 stability. Thus, downregulation of METTL3 resulted in the upregulation of AGAP2-AS1 in psoriasis. AGAP2-AS1 functioned as a competitive endogenous RNA by sponging miR-424-5p to upregulate AKT3, activate AKT/mTOR pathway, as well as promote cell proliferation in keratinocytes. CONCLUSION: AGAP2-AS1 is upregulated in the skin tissue of psoriasis patients and m6A methylation was involved in its upregulation. AGAP2-AS1 promotes keratinocyte proliferation through miR-424-5p/AKT/mTOR axis and may be a promising target for psoriasis therapy.

Application of a second opinion ultrasound in Breast Imaging Reporting and Data System 4A cases: can immediate biopsy be avoided?

OBJECTIVE: The probability of malignancy in women who are diagnosed with a Breast Imaging Reporting and Data System (BI-RADS) 4A score is low. Application of a second opinion ultrasound (SOUS), which is low in cost and minimally invasive, may lower the biopsy rate for patients who fall into this category. This study aimed to apply SOUS to patients with a BI-RADS score of 4A and predict the pathological results of a biopsy. METHODS: One hundred seventy-eight patients were analyzed. Univariate and multivariate analyses were performed to screen for predictive factors that are associated with malignancy. Categorical alteration of downgraded, unchanged, or upgraded was made after SOUS results. Changes in category were compared with biopsies to determine their predictive value of benignancy or malignancy. RESULTS: Independent factors associated with malignancy were age (>50 years), tumor size (≥20 mm), margin (not circumscribed), orientation (not parallel), and peripheral location, and an upgraded categorical alteration from SOUS. Downgraded categorical alterations were associated with benignancy. CONCLUSIONS: In BI-RADS 4A cases, a biopsy is recommended when independent factors are associated with malignancy. A downgraded result from an SOUS examination is a protective factor, supporting the likelihood of benignancy in these patients.

Treatment patterns and outcomes in children with infantile hemangiomas: A retrospective observational analysis.

OBJECTIVE: This study aimed to make use of real-world medical records to explore the clinical characteristics, treatments, and outcomes of infantile hemangiomas in southeastern China. METHODS: This study applied a retrospective observational method using real-world data derived from the electronic medical records of the Foshan Women and Children Hospital, southeastern China dated between June 2014 and June 2019. RESULTS: A total of 2427 patients with infantile hemangiomas were recruited in this study, including 942 (38.8%) males and 1485 (61.2%) females. Among the participants, 620 (25.5%) were high-risk infantile hemangioma, 449 (18.5%) were medium risk, and 1358 (56.0%) were low risk. A total of 14 treatment patterns in clinical practice were identified. The top 3 treatment patterns in each group of risk levels were the same: laser therapy, a combination of laser therapy and topical timolol maleate, and topical timolol maleate. The outcomes of the top 3 treatment patterns were significantly (P < 0.05) different in each risk group. CONCLUSION: Among the top 3 treatment patterns, laser therapy or a combination of laser therapy and topical timolol maleate were more likely to have an "Excellent" outcome.

Vorinostat targets UBE2C to reverse epithelial-mesenchymal transition and control cervical cancer growth through the ubiquitination pathway.

Vorinostat is a histone deacetylase inhibitor (HDACi) that was demonstrated in our previous study to inhibit the proliferation, migration, and invasion of cervical cancer cells by regulating the PI3K/Akt signaling pathway. However, the molecular mechanism of vorinostat in cervical cancer treatment remains to be further elucidated. A nude mouse xenograft model was established to analyze the antitumor effect of vorinostat in vivo. The combination of iTRAQ-based proteomics and parallel reaction monitoring (PRM) technology has proven to be an efficient and reliable method to identify potential targets for cancer chemotherapy. In this study, 254 differentially expressed proteins in vorinostat-treated cervical cancer cells, among which 180 were upregulated and 74 were downregulated, were identified by using an iTRAQ-based proteomic strategy. Subsequent bioinformatic and PRM analysis of these differentially expressed proteins indicated that UBE2C is a promising target of vorinostat in the inhibition of cervical cancer cell proliferation. We confirmed that the expression of endogenous UBE2C in cervical cancer cell lines was significantly higher than that in normal cervical epithelial cell lines. Additionally, we found that vorinostat downregulated the expression of UBE2C, SQSTM1/p62, N-cadherin, vimentin and upregulated E-cadherin in SiHa and HeLa cells. Our results also showed that vorinostat can downregulate the expression of SQSTM1/p62, N-cadherin, and vimentin during the treatment of cervical cancer cells by regulating UBE2C, while upregulating the expression of E-cadherin. In conclusion, vorinostat reverses epithelial-mesenchymal transition by targeting UBE2C and controls the proliferation of cervical cancer cells through the ubiquitination pathway. UBE2C can be used as a promising target for the development of vorinostat treatment strategies.

Downregulation of hsa_circRNA_0001400 Helps to Promote Cell Apoptosis Through Disruption of the circRNA_0001400-miR-326 Sponge in Cervical Cancer Cells.

Background: In recent years, circular RNAs (circRNAs) have been reported to serve as essential regulators in several human cancers. Nevertheless, the function and mechanism of circRNAs in cervical cancer remain elusive. Methods: Flow cytometry assays were performed to measure cell apoptosis and cell cycle. Colony Formation and transwell chamber were performed to measure cell migration and invasion. Double luciferase reporter for gene analysis was used to detect the interaction between hsa-circRNA_0001400, miR-326, and Akt. Relative protein levels were determined by immunoblotting and relative gene levels were determined by quantitative real-time PCR. Tumor Xenograft Modeling was used to evaluate the effect of hsa_circRNA_0001400_siRNA in vivo. Results: In the present study, we showed that hsa_circRNA_0001400 was highly expressed in cervical cancer tissues relative to in matched normal tissue. We found that hsa_circRNA_0001400_siRNA significantly promoted the apoptosis of cervical cancer cells and arrested the cell cycle and migration of cervical cancer cells. We showed that hsa_circRNA_0001400_siRNA can inhibit the protein expression of Akt and that the inhibition of miR-326 could rescue the inhibition of Akt in cervical cancer cells. We found that has-miR-326 was downregulated in cervical cancer tissues and hsa_circRNA_0001400_siRNA could increase the gene expression of has-miR-326. We also observed that hsa_circRNA_0001400_siRNA inhibited the growth and angiogenesis of SiHa xenografts in nude mice. Conclusion: In conclusion, this study provides evidence that the hsa_circRNA_0001400-miR-326-Akt network promotes cervical cancer progression. Notably, our findings demonstrate the novel antitumor effects of hsa_circRNA_0001400_siRNA in cervical cancer.

iTRAQ-based quantitative proteomic analysis of the inhibition of cervical cancer cell invasion and migration by metformin.

In recent years the anti-diabetic drug metformin has been shown to inhibit tumor growth, but the underlying mechanism is unclear. Our previous results showed that metformin can destroy the sponge effect of long-chain non-coding RNA MALAT1/miR-142-3p and inhibit the proliferation of cervical cancer cells. Metformin can inhibit the PI3K/Akt signaling pathway and synergizes with Nelfinavir to inhibit the proliferation and invasion of cervical cancer cells. In this study, we used iTRAQ-based proteomics, mass spectrometry-based targeted proteomics, immunoblotting, and bioinformatics to analyze the molecular mechanism by which metformin inhibits the proliferation and invasion of cervical cancer cells. We found that 53 proteins were differentially expressed in cervical cancer cells after metformin treatment, of which 20 were up-regulated and 33 were down-regulated. Bioinformatics analysis showed that the 53 differentially expressed proteins are negative regulators of receptor signaling that inhibit cell growth and are mainly enriched in cell growth and apoptosis signaling pathways. We performed PRM verification on 11 of the differentially expressed proteins and found that they were all associated with apoptosis. We also found that metformin up-regulated the expression of the tumor suppressor IGFBP7 to inhibit the proliferation and invasion of cervical cancer cells. Our results indicate that metformin mainly regulates the insulin signaling pathway and interferes with cell proliferation and apoptosis to inhibit proliferation and invasion of cervical cancer cells. These differentially expressed proteins may become new targets for the treatment of cervical cancer.

Vorinostat upregulates MICA via the PI3K/Akt pathway to enhance the ability of natural killer cells to kill tumor cells.

Vorinostat has good therapeutic efficacy against primary cutaneous T-cell lymphoma in the refractory stage. However, the molecular mechanism by which it inhibits solid tumors has not been clarified. To investigate the tumor inhibitory mechanism of vorinostat in cervical cancer, this study used Cell Counting Kit-8, flow cytometry, cell invasion and migration assays and the wound healing assay to evaluate the effects of vorinostat on cervical cancer cell proliferation, apoptosis, cell cycle, migration, and invasion. Real-time quantitative PCR and immunoblotting were used to detect gene and protein expression, respectively, of major histocompatibility class I-related chain A, phosphoinositide 3-kinase, phosphorylated PI3K p55 (Tyr199), and p-Akt (Ser473). The lactate dehydrogenase cytotoxicity assay was used to evaluate the ability of natural killer-92 cells to lyse cervical cancer cells. A xenograft nude mouse model was established to analyze the anti-tumor effect of vorinostat in vivo. Our results showed that vorinostat inhibited the proliferation, migration, and invasion of cervical cancer cells. Vorinostat also induced apoptosis and cell-cycle arrest in the S phase, inhibited PI3K (p110α), p-PI3K p55 (Tyr199), and p-Akt (Ser473) protein expression and upregulated MICA expression in vitro and in vivo, and promoted NK-92 cell-mediated cervical cancer cell lysis. The ability of vorinostat to upregulate MICA expression in cervical cancer cells was related to PI3K/Akt signaling. In brief, vorinostat upregulated MICA through the PI3K/Akt pathway and enhanced the sensitivity of cervical cancer cells to the NK cell-mediated cytolytic reaction. The results of this study demonstrate that vorinostat has anti-solid tumor effects on cervical cancer.

Metformin inhibits cervical cancer cell proliferation by modulating PI3K/Akt-induced major histocompatibility complex class I-related chain A gene expression.

BACKGROUND: Recent studies have shown that the classic hypoglycemic drug metformin inhibits tumor growth; however, the underlying mechanism remains unclear. We previously showed that metformin disrupts the sponge effect of long non-coding RNA MALAT1/miR-142-3p to inhibit cervical cancer cell proliferation. In this study, we interrogated the ability of metformin to modulate the anti-tumor immune response in cervical cancer. METHODS: The cell counting kit-8 assay was used to detect the viability of cervical cancer cells. Flow cytometry assays were performed to measure cell apoptosis and cell cycle. Lactate dehydrogenase (LDH) cytotoxicity assay was used to detect NK Cell Cytotoxicity. Relative protein levels were determined by immunoblotting and relative gene levels were determined by quantitative real-time PCR. Tumor Xenograft Modeling was used to evaluate the effect of metformin in vivo. RESULTS: Metformin inhibited cervical cancer cell proliferation, cervical cancer xenograft growth, expression of PCNA, p-PI3K and p-Akt. Moreover metformin induced cervical cancer cell apoptosis and caused cancer cell cycle arrest. In addition, metformin upregulated the expression of DDR-1 and p53 in human cervical cancer cells. Furthermore, metformin also regulated the mRNA and protein expression of MICA and HSP70 on the surface of human cervical cancer cells via the PI3K/Akt pathway, enhancing NK cell cytotoxicity. CONCLUSIONS: In conclusion, our results suggest that metformin may be used as immunopotentiator to inhibit cervical cancer progression and may be considered a viable candidate for combination therapy with immunotherapy.

miR-376c-3p modulates the properties of breast cancer stem cells by targeting RAB2A.

MicroRNAs (miRNAs/miRs) negatively regulate gene expression and participate in various cellular processes. miRNA dysregulation is associated with cancer progression. The present study aimed to identify the miRNAs that participate in breast cancer tumorigenesis and determine the mechanism that underlies this. miRNA microarray data analysis and validation assays indicated that miR-376c-3p was downregulated in breast tumour tissues and breast cancer stem cells (BCSCs) compared with adjacent non-cancerous tissues and MCF-10A cells, respectively. Ras-related protein Rab-2A (RAB2A) was predicted as a target of miR-376c-3p, which was confirmed by conducting further experiments. miR-376c-3p regulated the BCSC population and the expression of stem cell regulatory genes by targeting RAB2A. By performing mammosphere, Cell Counting Kit-8, colony formation and transwell invasion assays, it was demonstrated that miR-376c-3p also inhibited BCSC self-renewal, proliferation and invasion by regulating RAB2A expression. Using a xenograft mouse model, it was revealed that miR-376c-3p overexpression suppressed breast cancer growth in vivo. In conclusion, the results indicated that miR-376c-3p targeted RAB2A to regulate BCSC fate and properties; therefore, miR-376c-3p may serve as a potential therapeutic target for breast cancer.