Cisplatin-based chemotherapeutic regimens are the most frequently used adjuvant treatments for many types of cancer. However, the development of chemoresistance to cisplatin results in treatment failure. Despite the significant developments in understanding the mechanisms of cisplatin resistance, effective strategies to enhance the chemosensitivity of cisplatin are lacking. Phytochemicals are naturally occurring plant-based compounds that can augment the anti-cancer activity of cisplatin, with minimal side effects. Notably, some novel phytochemicals, such as curcumin, not only increase the efficacy of cisplatin but also decrease toxicity induced by cisplatin. However, the exact mechanisms underlying this process remain unclear. In this review, we discussed the progress made in utilizing phytochemicals to enhance the anti-cancer efficacy of cisplatin. We also presented some ideal phytochemicals as novel agents for counteracting cisplatin-induced organ damage.

Cisplatin, as the first-line anti-tumor agent, is widely used for treatment of a variety of malignancies including non-small cell lung cancer (NSCLC). However, the acquired resistance has been a major obstacle for the clinical application. Scutellarin is a active flavone extracted from Erigeron breviscapus Hand-Mazz that has been shown to exhibit anticancer activities on various types of tumors. Here, we reported that scutellarin was capable of sensitizing A549/DDP cells to cisplatin by enhancing apoptosis and autophagy. Mechanistic analyses indicated that cisplatin-induced caspase-3-dependent apoptosis was elevated in the presence of scutellarin through activating extracellular signal-regulated kinases (ERK)-mediated p53 pathway. Furthermore, scutellarin also promoted cisplatin-induced cytotoxic autophagy, downregulated expression of p-AKT and c-met. Deficiency of c-met reduced p-AKT level, and inhibition of p-AKT or c-met improved autophagy in A549/DDP cells. Interestingly, loss of autophagy attenuated the synergism of this combination. In vivo, the co-treatment of cisplatin and scutellarin notably reduced the tumor size when compared with cisplatin treatment alone. Notably, scutellarin significantly reduced the toxicity generated by cisplatin in tumor-bearing mice. This study identifies the unique role of scutellarin in reversing cisplatin resistance through apoptosis and autophagy, and suggests that combined cisplatin and scutellarin might be a novel therapeutic strategy for patients with NSCLC.

Cisplatin is one of the most frequently used chemotherapeutic agents for treatment of a wide range of cancer types. Nevertheless, the intrinsic or acquired resistance to cisplatin remains a major obstacle for cancer therapy. There are a number of factors contributing to the onset of this phenotype resistance. Signal transducers and activators of transcription 3 (STAT3) is constitutively activated in many cancer types, and such hyperactivation is associated with a poor clinical prognosis. In addition, STAT3 inhibitors have shown the ability to enhance the anti-tumor efficacy of cisplatin. In this review, we summarized the current knowledge of the STAT3 pathway in cancer treatment and its contribution to cisplatin resistance. Moreover, this review focuses on targeting STAT3 inhibition to overcome cisplatin resistance.

Cisplatin remains the standard first-line chemotherapeutic agent in the treatment of many types of cancers, but its clinical application is hindered by its severe nephrotoxicity. Previous studies reported that scutellarin enhanced the anti-cancer activity of cisplatin in lung cancer cells, with no confirmation on cisplatin-induced renal damage. Here, we investigated the nephroprotective effect of scutellarin on cisplatin-induced renal injury and its underlying mechanisms. Renal function, histological change, inflammation, apoptosis, autophagy and involved pathways were investigated. Pretreatment with scutellarin prevented cisplatin-induced decline of renal function including BUN, CRE, and histological damage. Scutellarin also reduced renal inflammation by suppressing the levels of pro-inflammatory cytokine, TNF-α and IL-6. Similarly, scutellarin administration inhibited apoptosis triggered by cisplatin through reducing the expressions of Cleaved caspase-3, Cleaved PARP, p53, and the ratio of Bax/Bcl-2. Moreover, scutellarin prevented cisplatin-induced inhibition of autophagy via enhancing LC3-II/LC3-I and Atg7, and inhibition of p62. Of note, the activations of JNK, ERK, p38 and stat3 induced by cisplatin were strikingly attenuated in scutellarin-treated mice. Thus, these results provide compelling evidence that scutellarin is a novel nephroprotectant against cisplatin-induced renal toxicity.

Curative molecular therapy for non-small cell lung cancer (NSCLC) is still lacking. Scutellarin, an active flavone extracted from Erigeron breviscapus Hand-Mazz, displays anti-tumor property in diverse cancer types, yet its tumor-suppressive effect on NSCLC is not reported. In this study, we found that scutellarin significantly inhibited the proliferation of NSCLC cells, induced cell apoptosis, and triggered autophagy. Notably, inhibition of autophagy with inhibitor HCQ attenuated the anti-proliferative activity of scutellarin, indicating that scutellarin-induced autophagy is antineoplastic. In addition, HCQ treatment reduced scutellarin-induced apoptosis. Further study demonstrated that scutellarin stimulated phosphorylation of ERK1/2, and inhibition of ERK1/2 with inhibitor U0126 markedly attenuated scutellarin-induced autophagy. Similarly, scutellarin downregulated the expression of p-AKT, and AKT inhibitor MK-2206 induced autophagy. Moreover, there also existed crosstalk between ERK and AKT pathways. Finally, in vivo xenograft nude mice experiment proved that scutellarin treatment significantly reduced tumor growth and increased the levels of LC3-II and p-ERK1/2, suppressed p-AKT in mice tumors. Thus, our study for the first time uncovered the anti-cancer function of scutellarin on NSCLC cells, and might provide a potential novel therapy for treatment of patients with NSCLC.

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the second leading cause of cancer-related deaths worldwide. Despite new technologies in diagnosis and treatment, the incidence and mortality of HCC continue rising. And its pathogenesis is still unclear. As a highly conserved protein of the Golgi apparatus, Golgi phosphoprotein 3 (GOLPH3) has been shown to be involved in tumorigenesis of HCC. This study aimed to explore the exact oncogenic mechanism of GOLPH3 and provide a novel diagnose biomarker and therapeutic strategy for patients with HCC. Firstly, the expression of GOLPH3 was detected in the HCC tissue specimens and HCC cell lines. Secondly, RNA interference was used for GOLPH3 gene inhibition. Thirdly, cell proliferation was analyzed by MTT; cell apoptosis was analyzed by Annexin-V/PI staining, Hoechst 33,342 staining and caspase 3/7 activity assay. Fourthly, xenograft tumor model was used to study the function of GOLPH3 in tumor growth in vivo. Finally, western blotting and immunohistochemistry were used to investigate the role of GOLHP3 in the mTOR signaling pathway. Data showed that the mRNA and protein expression of GOLPH3 were up-regulated in HCC tumor tissue and cell lines compared with those of control (P < 0.05). Correlation analyses showed that GOLPH3 expression was positively correlated with serum alpha-fetoprotein level (AFP, P = 0.006). Knockdown GOLPH3 expression inhibited proliferation and promoted apoptosis in HCC cell lines. What’s more, knockdown GOLPH3 expression led to tumor growth restriction in xenograft tumor model. The expression of phosphorylated mTOR, AKT and S6 K1 were significantly higher in HCC tumor tissue and cell lines compared with those in normal liver tissues (p < 0.05). While the phosphorylated mTOR, AKT and S6 K1 were much lower when diminished GOLPH3 expression in HCC cell lines both in vitro and in vivo. The current study suggests that GOLPH3 contributes to the tumorigenesis of HCC by activating mTOR signaling pathway. GOLPH3 is a promising diagnose biomarker and therapeutic target for HCC. Our study may provide a scientific basis for developing effective approaches to treat the HCC patients with GOLPH3 overexpression.