Down-modulation of Bcl-2 sensitizes PTEN-mutated prostate cancer cells to starvation and taxanes

Diospyros rhodocalyx Kurz induces mitochondrial-mediated apoptosis via BAX, Bcl-2, and caspase-3 pathways in LNCaP human prostate cancer cell line

Background

Prostate cancer (PCa) is one of the causes of death in men worldwide. Although treatment strategies have been developed, the recurrence of the disease and consequential side effects remain an essential concern. Diospyros rhodocalyx Kurz, a traditional Thai medicine, exhibits diverse therapeutic properties, including anti-cancer activity. However, its anti-cancer activity against prostate cancer has not been thoroughly explored. This study aims to evaluate the anti-cancer activity and underlying mechanisms of the ethyl acetate extract of D. rhodocalyx Kurz (EADR) related to apoptosis induction in the LNCaP human prostate cancer cell line.

Methods

Ethyl acetate was employed to extract the dried bark of D. rhodocalyx Kurz. The cytotoxicity of EADR on both LNCaP and WPMY-1 cells (normal human prostatic myofibroblast cell line) was evaluated using MTS assay. The effect of EADR on the cell cycle, apoptosis induction, and alteration in mitochondrial membrane potential (MMP) was assessed by the staining with propidium iodide (PI), Annexin V-FITC/PI, and JC-1 dye, respectively. Subsequent analysis was conducted using flow cytometry. The expression of cleaved caspase-3, BAX, and Bcl-2 was examined by Western blotting. The phytochemical profiling of the EADR was performed using gas chromatography-mass spectrometry (GC-MS).

Results

EADR exhibited a dose-dependent manner cytotoxic effect on LNCaP cells, with IC50 values of 15.43 and 12.35 µg/mL after 24 and 48 h, respectively. Although it also exhibited a cytotoxic effect on WPMY-1 cells, the effect was comparatively lower, with the IC50 values of 34.61 and 19.93 µg/mL after 24 and 48 h of exposure, respectively. Cell cycle analysis demonstrated that EADR did not induce cell cycle arrest in either LNCaP or WPMY-1 cells. However, it significantly increased the sub-G1 population in LNCaP cells, indicating a potential induction of apoptosis. The Annexin V-FITC/PI staining indicated that EADR significantly induced apoptosis in LNCaP cells. Subsequent investigation into the underlying mechanism of EADR-induced apoptosis revealed a reduction in MMP as evidenced by JC-1 staining. Moreover, Western blotting demonstrated that EADR treatment resulted in the upregulation of BAX, downregulation of BCL-2, and elevation of caspase-3 cleavage in LNCaP cells. Notably, the epilupeol was a prominent compound in EADR as identified by GC-MS.

Conclusion

The EADR exhibits anti-cancer activity against the LNCaP human prostate cancer cell line by inducing cytotoxicity and apoptosis. Our findings suggest that EADR promotes apoptosis by upregulating pro-apoptotic BAX, whereas downregulation of anti-apoptotic Bcl-2 results in the reduction of MMP and the activation of caspase-3. Of particular interest is the presence of epilupeol, a major compound identified in EADR, which may hold promise as a candidate for the development of therapeutic agents for prostate cancer.

A pan-cancer analysis of the oncogenic and immunological roles of transglutaminase 1 (TGM1) in human cancer

BACKGROUND

There is currently a limited number of studies on transglutaminase type 1 (TGM1) in tumors. The objective of this study is to perform a comprehensive analysis across various types of cancer to determine the prognostic significance of TGM1 in tumors and investigate its role in the immune environment.

METHOD

Pan-cancer and mutational data were retrieved from the TCGA database and analyzed using R (version 3.6.4) and its associated software package. The expression difference and prognosis of TGM1 were examined, along with its correlation with tumor heterogeneity, stemness, mutation landscape, and RNA modification. Additionally, the relationship between TGM1 expression and tumor immunity was investigated using the TIMER method.

RESULTS

TGM1 is expressed differently in various tumors and normal samples and is associated with the overall survival and progression-free time of KIRC, ACC, SKCM, LIHC, and STES. In LICH, we found a negative correlation between TGM1 expression and 6 indicators of tumor stemness. The mutation frequencies of BLCA, LIHC, and KIRC were 1.7%, 0.3%, and 0.3% respectively. In BLCA and BRCA, there was a significant correlation between TGM1 expression and the infiltration of CD4 + T cells, CD8 + T cells, neutrophils, and dendritic cells.

CONCLUSION

TGM1 has the potential to serve as both a prognostic marker and a drug target.

Dual targeting of the androgen receptor and PI3K/AKT/mTOR pathways in prostate cancer models improves antitumor efficacy and promotes cell apoptosis

Prostate cancer is a frequent malignancy in older men and has a very high 5-year survival rate if diagnosed early. The prognosis is much less promising if the tumor has already spread outside the prostate gland. Targeted treatments mainly aim at blocking androgen receptor (AR) signaling and initially show good efficacy. However, tumor progression due to AR-dependent and AR-independent mechanisms is often observed after some time, and novel treatment strategies are urgently needed. Dysregulation of the PI3K/AKT/mTOR pathway in advanced prostate cancer and its implication in treatment resistance has been reported. We compared the impact of PI3K/AKT/mTOR pathway inhibitors with different selectivity profiles on in vitro cell proliferation and on caspase 3/7 activation as a marker for apoptosis induction, and observed the strongest effects in the androgen-sensitive prostate cancer cell lines VCaP and LNCaP. Combination treatment with the AR inhibitor darolutamide led to enhanced apoptosis in these cell lines, the effects being most pronounced upon cotreatment with the pan-PI3K inhibitor copanlisib. A subsequent transcriptomic analysis performed in VCaP cells revealed that combining darolutamide with copanlisib impacted gene expression much more than individual treatment. A comprehensive reversal of the androgen response and the mTORC1 transcriptional programs as well as a marked induction of DNA damage was observed. Next, an in vivo efficacy study was performed using the androgen-sensitive patient-derived prostate cancer (PDX) model LuCaP 35 and a superior efficacy was observed after the combined treatment with copanlisib and darolutamide. Importantly, immunohistochemistry analysis of these treated tumors showed increased apoptosis, as revealed by elevated levels of cleaved caspase 3 and Bcl-2-binding component 3 (BBC3). In conclusion, these data demonstrate that concurrent blockade of the PI3K/AKT/mTOR and AR pathways has superior antitumor efficacy and induces apoptosis in androgen-sensitive prostate cancer cell lines and PDX models.

Atorvastatin Enhances Inhibitory Effects of Irradiation on Tumor Growth by Reducing MSH2 Expression both in Prostate Cancer Cells and Xenograft Tumor Models

BACKGROUND

Prostate cancer (PCa) is the fourth most common tumor in males.

OBJECTIVE

To investigate effects of atorvastatin (AS) on PCa cells proliferation and clarify the associated mechanisms.

METHODS

PCa cell lines were cultured and treated with irradiation (IR) (4 Gy), AS (6 μg/ml), transfected with Bcl-2 siRNA, and then divided into different groups. Xenograft tumor mouse model was established. Bcl-2 and MSH2 gene transcription and protein expression were evaluated using RT-PCR assay and western blot assay. Plate clone formation assay was employed to examine colony formation. MTT assay was used to detect cell viabilities. Flow cytometry analysis was utilized to verify apoptosis. Co-immunoprecipitation and immuno-fluorescence assay were used to identify interaction between Bcl-2 and MSH2.

RESULTS

IR significantly reduced colony formation, enhanced Bcl-2 and reduced MSH2 gene transcription in PCa cells compared to un-treated cells (p<0.05). AS significantly strengthened radio-therapeutic effects of IR on colony formation, decreased cell apoptosis and increased Bcl-2 gene transcription/protein expression in PCa cells compared to single IR treatment cells (p<0.05). AS combining IR down-regulated MSH2 gene transcription/protein expression in PCa cells compared to single IR treatment cells (p<0.05). Bcl-2 interacted with MSH2 both in PCa cells and tumor tissues administrating with AS. AS enhanced reductive effects of IR on tumor size of Xenograft tumor mice.

CONCLUSION

Atorvastatin administration enhanced inhibitory effects of IR either on PCa cells or on tumor size of Xenograft tumor mice. The inhibitory effects of atorvastatin were mediated by reducing MSH2 expression and triggering interaction between Bcl-2 and MSH2, both in vitro and in vivo levels.

Mechanisms of Taxane Resistance

The taxane family of chemotherapy drugs has been used to treat a variety of mostly epithelial-derived tumors and remain the first-line treatment for some cancers. Despite the improved survival time and reduction of tumor size observed in some patients, many have no response to the drugs or develop resistance over time. Taxane resistance is multi-faceted and involves multiple pathways in proliferation, apoptosis, metabolism, and the transport of foreign substances. In this review, we dive deeper into hypothesized resistance mechanisms from research during the last decade, with a focus on the cancer types that use taxanes as first-line treatment but frequently develop resistance to them. Furthermore, we will discuss current clinical inhibitors and those yet to be approved that target key pathways or proteins and aim to reverse resistance in combination with taxanes or individually. Lastly, we will highlight taxane response biomarkers, specific genes with monitored expression and correlated with response to taxanes, mentioning those currently being used and those that should be adopted. The future directions of taxanes involve more personalized approaches to treatment by tailoring drug-inhibitor combinations or alternatives depending on levels of resistance biomarkers. We hope that this review will identify gaps in knowledge surrounding taxane resistance that future research or clinical trials can overcome.

PTEN: A Thrifty Gene That Causes Disease in Times of Plenty?

The modern obesity epidemic with associated disorders of metabolism and cancer has been attributed to the presence of "thrifty genes". In the distant past, these genes helped the organism to improve energy efficiency and store excess energy safely as fat to survive periods of famine, but in the present day obesogenic environment, have turned detrimental. I propose PTEN as the likely gene as it has functions that span metabolism, cancer and reproduction, all of which are deranged in obesity and insulin resistance. The activity of PTEN can be calibrated in utero by availability of nutrients by the methylation arm of the epigenetic pathway. Deficiency of protein and choline has been shown to upregulate DNA methyltransferases (DNMT), especially 1 and 3a; these can then methylate promoter region of PTEN and suppress its expression. Thus, the gene is tuned like a metabolic rheostat proportional to the availability of specific nutrients, and the resultant "dose" of the protein, which sits astride and negatively regulates the insulin-PI3K/AKT/mTOR pathway, decides energy usage and proliferation. This "fixes" the metabolic capacity of the organism periconceptionally to a specific postnatal level of nutrition, but when faced with a discordant environment, leads to obesity related diseases.

Key Genes And Pathways Controlled By E2F1 In Human Castration-Resistant Prostate Cancer Cells

Background

Treatment of castration-resistant prostate cancer (CRPC) is an enormous challenge. As E2F transcription factor 1 (E2F1) is an essential factor in CRPC, this study investigated the genes and pathways controlled by E2F1 and their effects on cellular behavior in CRPC.

Methods

In vitro assays were used to evaluate cellular proliferation, apoptosis, and behavior. Cellular expression was quantified by RNA sequencing (RNA-seq). Gene co-expression was assessed using the GeneMANIA database, and correlations were analyzed with the GEPIA server. Altered pathways of differentially expressed genes (DEGs) were revealed by functional annotation. Module analysis was performed using the STRING database and hub genes were filtered with the Cytoscape software. Some DEGs were validated by real-time quantitative PCR (RT-qPCR).

Results

Knockdown of E2F1 significantly inhibited proliferation and accelerated apoptosis in PC3 cells but not in DU145 cells. Invasion and migration were reduced for both cell lines. A total of 1811 DEGs were identified in PC3 cells and 27 DEGs in DU145 cells exhibiting E2F1 knockdown. Ten overlapping DEGs, including TMOD2 and AIF1L, were identified in both knockdown cell lines and were significantly enriched for association with actin filament organization pathways. TMOD2 and KREMEN2 were genes co-expressed with E2F1; six overlapping DEGs were positively correlated with transcription factor E2F1. DEGs of the PC3 and DU145 groups were associated with multiple pathways. Five DEGs that overlapped between the two cell lines and three hub DEGs from PC3 cells were validated by RT-qPCR.

Conclusion

The results of this study suggest that E2F1 has a critical role in regulating actin filaments, as indicated by the change in expression level of several genes, including TMOD2 and AIF1L, in CRPC. This extends our understanding of the cellular responses affected by E2F1 in CRPC.

ERp57‑small interfering RNA silencing can enhance the sensitivity of drug‑resistant human ovarian cancer cells to paclitaxel

ERp57 has been identified to be associated with the chemoresistance of human ovarian cancer. However, its biological roles in the chemoresistance phenotype remain unclear. In the present study, the association of ERp57 with paclitaxel‑resistant cellular behavior was investigated and the sensitivity enhancement of chemoresistant human ovarian cancer cells to paclitaxel was examined using ERp57‑small interfering (si)RNA silencing. Cell viability, cell proliferation, cell apoptosis and cell migration were detected using an MTT assay, clonogenic assay, flow cytometry analysis and transwell assay. Furthermore, mRNA expression levels of ERp57 and protein expression levels of ERp57, STAT3, phosphorylated STAT3, PCNA, nucelolin, TUBB3, P-gp, vimentin, Bcl-2, Bax, Bcl-xl, p53, MMP1, MMP2 and MMP9 of paclitaxel-sensitive human SKOV3 ovarian cancer cells were compared with paclitaxel-resistant counterpart SKOV3/tax using the real-time PCR and western blot analysis. ERp57 was highly expressed in the paclitaxel‑resistant SKOV3/tax cells, and experimental results concluded that the paclitaxel‑resistance phenotype was due primarily to the activation of the STAT3 signaling pathway. ERp57 overexpression by lentiviral particle infection decreased the sensitivity of SKOV3 cells to paclitaxel. Furthermore, ERp57‑siRNA silencing restored paclitaxel sensitivity of SKOV3/tax cells. Notably, the IC50 value of ERp57‑siRNA silenced SKOV3/tax cells was reduced to the original level and colony survival was significantly decreased in comparison with that of SKOV3/tax cells. Additionally, co‑treatment of ERp57‑siRNA silencing and paclitaxel could inhibit the STAT3 signaling pathway and downregulate the expression levels of downstream proteins. Notably, ERp57‑siRNA and 100 nM paclitaxel co‑treatment downregulated Bcl‑2, Bcl‑xl, MMP2, MMP9, TUBB3 and P‑gp expression levels and upregulated the expression of Bax protein. Furthermore, co‑treatment promoted change of the isoform of p53 to p53/p47. Bioinformatics analyses supported the experimental observations that ERp57 was associated with drug resistance in ovarian cancer. The present study implies that ERp57 is a potential therapeutic target for the treatment of paclitaxel‑resistant human ovarian cancer.

Molecular mechanisms regarding potassium bromate‑induced cardiac hypertrophy without apoptosis in H9c2 cells

Cardiac hypertrophy is commonly involved in cardiac injury. Oxidative stress can induce cardiac hypertrophy with apoptosis. Potassium bromate (KBrO3) has been widely used as a food additive due to its oxidizing properties. In the present study, the rat‑derived heart cell line H9c2 was used to investigate the effect of KBrO3 on cell size. KBrO3 increased cell size at concentrations <250 µM, in a dose‑dependent manner. Additionally, KBrO3 also promoted the gene expression of two biomarkers of cardiac hypertrophy, brain/B‑type natriuretic peptides (BNP) and β‑Myosin Heavy Chain (β‑MHC). However, apoptosis remained unobserved in these cells. Moreover, mediation of free radicals was investigated using a fluorescence assay, and it was observed that superoxide and reactive oxygen species (ROS) levels increased with KBrO3. Effects of KBrO3 were significantly reduced by tiron at concentrations sufficient to produce antioxidant‑like action. Additionally, signals involved in cardiac hypertrophy such as calcineurin and nuclear factor of activated T‑cells (NFAT) were also determined using western blot analysis. KBrO3 increased the protein levels of both these molecules which were decreased by tiron in a dose‑dependent manner. Additionally, cyclosporine A attenuated the cardiac hypertrophy induced by KBrO3 in H9c2 cells at concentrations effective to inhibit calcineurin, in addition to reducing mRNA levels of BNP or β‑MHC. Finally, apoptosis was also identified in H9c2 cells incubated with KBrO3 at concentrations >300 µM. Collectively, these results provided a novel perspective that KBrO3 induces cardiac hypertrophy without apoptosis at a low dose through the generation of ROS, activating the calcineurin/NFAT signaling pathway in H9c2 cells. Therefore, at a dose <250 µM, KBrO3 can be applied as an inducer of cardiac hypertrophy without apoptosis in H9c2 cells. KBrO3 can also be developed as a tool to induce cardiac hypertrophy in animals.

Melatonin Analogue Antiproliferative and Cytotoxic Effects on Human Prostate Cancer Cells

Melatonin has been indicated as a possible oncostatic agent in different types of cancer, its antiproliferative role being demonstrated in several in vitro and in vivo experimental models of tumors. Specifically, melatonin was proven to inhibit cell growth of both androgen-dependent and independent prostate cancer cells, through various mechanisms. A number of melatonin derivatives have been developed and tested for their role in the prevention and treatment of neoplastic diseases. We recently proved the in vitro and in vivo anticancer activity of UCM 1037, a newly-synthetized melatonin analogue, on melanoma and breast cancer cells. In this study we evaluated UCM 1037 effects on cell proliferation, cell cycle distribution, and cytotoxicity in LNCaP, PC3, DU145, and 22Rv1 prostate cancer cells. We demonstrated significant dose- and time-dependent UCM 1037 antiproliferative effects in androgen-sensitive LNCaP and 22Rv1 cells. Data from flow cytometric studies suggest that UCM 1037 is highly cytotoxic in androgen-sensitive prostate cancer cells, although no substantial increase in the apoptotic cell fraction has been observed. UCM 1037 cytotoxic effects were much less evident in androgen-insensitive PC3 and DU145 cells. Experiments performed to gain insights into the possible mechanism of action of the melatonin derivative revealed that UCM 1037 down-regulates androgen receptor levels and Akt activation in LNCaP and 22Rv1 cells.

Induction of apoptosis in prostate cancer by ginsenoside Rh2

The therapeutic action of ginsenoside Rh2 on several cancer models has been reported. This study aimed to evaluate its apoptotic effect on prostate cancer and the underlying mechanism. Cultured DU145 cells were treated with Rh2 (5 × 10^-5 to 1 × 10^-4 M), peroxisome proliferator-activated receptor-delta (PPAR-delta) antagonist GSK0660 (1 × 10^-6 to 5 × 10^-6 M); or small interfering RNA (siRNA) of PPAR-delta. The treatment effects were evaluated with cell viability assay, life/death staining and flow cytometry for apoptosis. Immunostaining was used for reactive oxygen species (ROS) and superoxide detection. Western blot analysis for PPAR-delta and signal transducer and activator of transcription 3 (STAT3) protein expression were performed. The results showed that Rh2 significantly decreased DU145 cell survival and increased cell apoptosis. ROS and superoxide induction, PPAR-delta up-regulation and phosphorylated STAT3 (p-STAT3) down-regulation by Rh2 were demonstrated. GSK0660 partially but significantly inhibited the Rh2-induced apoptosis and restored cell viability. Treatment with siRNA reversed the Rh2-induced apoptosis as well as changes in PPAR-delta and p-STAT3 expression. In conclusion, our findings have demonstrated that ginsenoside Rh2 induces prostate cancer DU145 cells apoptosis through up-regulation of PPAR-delta expression which is associated with p-STAT3 up-regulation and ROS/superoxide induction. Rh2 may be potentially useful in the treatment of prostate cancer.

Phosphorylated Akt Protein at Ser473 Enables HeLa Cells to Tolerate Nutrient-Deprived Conditions

Background:

Despite angiogenesis, many tumours remain hypovascular and starved of nutrients while continuing to grow rapidly. The specific biochemical mechanisms associated with starvation resistance, austerity, may be new biological characters of cancer that are critical for cancer progression.

Objective:

This study aim was to investigate the effect of nutrient starvation on HeLa cells and the possible mechanism by which the cells are able to tolerate nutrient-deprived conditions.

Methods:

Nutrient starvation was achieved by culturing HeLa cells in nutrient-deprived medium (NDM) and cell survival was estimated by using cell counting kit-8. The effect of starvation on cell cycle distribution and the quantitative analysis of apoptotic cells were investigated by flow cytometry using propidium iodide staining. Western blotting was used to detect the expression levels of Akt and phosphorylated Akt at Ser473 (Ser⁴⁷³p-Akt) proteins.

Results:

HeLa cells displayed extremely long survival when cultured in NDM. The percentage of apoptotic HeLa cells was significantly increased by starvation in a time-dependent manner. A significant increase in the expression of Ser⁴⁷³p-Akt protein after starvation was also observed. Furthermore, it was found that Akt inhibitor III molecule inhibited the cells proliferation in a concentration- and time-dependent manner.

Conclusion:

Results of the present study provide evidence that Akt activation may be implicated in the tolerance of HeLa cells for nutrient starvation and may help to suggest new therapeutic strategies designed to prevent austerity of cervical cancer cells through inhibition of Akt activation.

Implications of Bcl-2 and its interplay with other molecules and signaling pathways in prostate cancer progression

INTRODUCTION

Among several genetic alterations involved in the progression of prostate cancer, B cell lymphoma gene number 2 (BCL-2) is an important target molecule in the progression of androgen-independent prostate cancer (AIPC) after androgen ablation or castration. Nevertheless, the molecular mechanism of BCL-2 in prostate cancer progression remains elusive and controversial. In the current review, we discuss the critical role of BCL-2 in the carcinogenesis of prostate cancer with experimental evidences on the BCL-2 molecular networks in AIPC and androgen-dependent prostate cancer (ADPC) and subsequently suggest perspective research targeting BCL-2. Areas covered: This review focused on the molecular implications of BCL-2 in association with other molecules and signaling pathways involved in the progression and carcinogenesis of prostate cancer. Expert opinion: BCL-2 plays a pivotal role in the progression of AIPC than in ADPC since androgen represses BCL-2. BCL-2 acts as a pro-survival molecule in association with androgen-related signaling in the progression of ADPC, while BCL-2 upregulation, PTEN loss, PI3K/AKT phosphorylation and receptor tyrosine kinase (RTK) activation are primarily involved in AIPC. To identify more effective prostate cancer therapy, further mechanistic studies are required with BCL-2 inhibitors in AIPC and ADPC, considering a multi-target therapy against BCL-2 and its related signaling.

Increase of human prostate cancer cell (DU145) apoptosis by telmisartan through PPAR-delta pathway

The effect of telmisartan on prostate cancer DU145 cell survival and the underlying mechanism of apoptosis involving peroxisome proliferator-activated receptor (PPAR) pathway were investigated. Cultured DU145 cells were treated pharmacologically with telmisartan and GSK0660 (a PPAR-delta antagonist); or by RNA interference with siRNA of PPAR-delta. The treatment effects on cell survival were evaluated with cell viability assay, life and dead cell staining and flow cytometry. Western blot analysis for PPAR-delta protein expression was also performed. The results showed that telmisartan (0-80 µm) dose-dependently reduced DU145 cell survival. Flow cytometry demonstrated cancer cell cycle arrest with increase of sub-G1 phase. GSK0660 partially but significantly restored the telmisartan-treated cell viability. Similarly, siRNA of PPAR-delta significantly reversed the telmisartan-induced apoptosis. Western blot showed that telmisartan significantly increased DU145 cell PPAR-delta protein expression. Co-incubation with siRNA of PPAR-delta inhibited the telmisartan effect of PPAR-delta up-regulation. In conclusion, telmisartan induces prostate cancer DU145 cells apoptosis through the up-regulation of PPAR-delta protein expression. Pharmacological inhibition or genetic silencing of PPAR-delta activity can both reverse the telmisartan-induced apoptotic effect. Thus the PPAR-delta pathway might be a potential target for the treatment of prostate cancer.

Downregulation of miR-363 increases drug resistance in cisplatin-treated HepG2 by dysregulating Mcl-1

Systemic therapy with cytotoxic agents provides marginal benefit in hepatocellular carcinoma (HCC) treatment especially for patients with advanced HCC. Cisplatin is one of the most active cytotoxic agents for HCC treatment. However, acquisition of cisplatin resistance is common, and one important underlying mechanism of such resistance is apoptosis-resistance. In this study, we found that miR-363 levels were significantly decreased in HCC patients treated with cisplatin-based chemotherapy. MiR-363 levels were also lower in cisplatin-resistant HepG2 (HepG2-R) cells than in HepG2 cells. Exogenous miR-363 significantly overcame cisplatin resistance in HepG2-R cells, whereas miR-363 knockdown increased the cell viability during cisplatin treatment. We further demonstrated that miR-363 directly targeted to Mcl-1 3'-UTR (3'-Untranslated Regions). Downregulation of miR-363 resulted in upregulation of Mcl-1 which is a key member of anti-apoptotic Bcl-2 family and increased drug resistance. We finally demonstrated that miR-363 decreased cisplatin resistance of HCC cell, partly by targeting Mcl-1. These data suggest that the combination of miR-363 and cisplatin may represent a novel approach in treatment for HCC, thus offering a new target for chemotherapy of HCC.