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Protein arginine methyltransferase 5 (PRMT5) functions as a tumor initiator to regulate several cancer progressions, such as proliferation and apoptosis, by catalyzing the symmetrical dimethylation (me2s) of arginine residues within targeted molecules. However, the exact role of PRMT5-mediated metastasis in lung cancer is not fully understood. Here, we illustrated its potential effects in lung cancer metastasis in vivo and vitro. PRMT5 was frequently overexpressed in lung tumors, and its expression was positively related to tumor stages, lymphatic metastasis and poor outcome. In this model, PRMT5 repressed the transcription of the miR-99 family by symmetrical dimethylation of histone H4R3, which increased FGFR3 expression and in turn activated Erk1/2 and Akt, leading to cell growth and metastasis in lung cancer. Furthermore, loss of PRMT5 exerted anti-metastasis effects on lung cancer progression by blocking histone-modification of miR-99 family. Overall, this study provides new insights into the PRMT5/miR-99 family/FGFR3 axis in regulating lung cancer progression and identifies PRMT5 as a promising prognostic biomarker and therapeutic target.

Retinal microglia cells contribute to vascular angiogenesis and vasculopathy induced by relative hypoxia. However, its concrete molecular mechanisms in shaping retinal angiogenesis have not been elucidated. Basigin, being involved in tumour neovasculogenesis, is explored to exert positive effects on retinal angiogenesis induced by microglia. Therefore, we set out to investigate the expression of basigin using a well‐characterized mouse model of oxygen‐induced retinopathy, which recapitulated hypoxia‐induced aberrant neovessel growth. Our results elucidate that basigin is overexpressed in microglia, which accumulating in retinal angiogenic sprouts. In vitro, conditioned media from microglia BV2 under hypoxia treatment increase migration and tube formation of retinal capillary endothelia cells, compared with media from normoxic condition. The angiogenic capacity of BV2 is inhibited after basigin knockdown by small interfering RNAs. A new molecular mechanism for high angiogenic capacity, whereby microglia cells release basigin via up‐regulation of PI3K‐AKT and IGF‐1 pathway to induce angiogenesis is unveiled. Collectively, our results demonstrate that basigin from hypoxic microglia plays a pivotal pro‐angiogenic role, providing new insights into microglia‐promoting retinal angiogenesis.

Curcumin, a yellow pigment derived from Curcuma longa Linn, has been favored by the Eastern as dietary ingredients for centuries. During the past decade, extensive investigations have revealed curcumin sensitized various chemotherapeutic agents in human breast, colon, pancreas, gastric, liver, brain and hematological malignant disorders in vivo and in vitro. Several pathways and specific targets including NF-κB, STAT3, COX-2, Akt and multidrug resistant protein have been identified to facilitate curcumin as a chemosensitizer. Recent studies suggest HIF-1α participated in the development of drug resistance in cancer cells and targeting HIF-1α either by RNAi or siRNA successfully overcame chemotherapeutic resistance. To investigate the mechanism basis of curcumin as a chemosensitizer in lung cancer, we examined curcumin's effects on HIF-1α in cis-platin (DDP) sensitive A549 and resistant A549/DDP cell lines by RT-PCR and Western blot. HIF-1α in A549/DDP cells was found to be overexpressed at both mRNA and protein levels together with a poor response to DDP. Results from transient transfection and flow cytometry showed the HIF-1α abnormality contributed to DDP resistance in A549/DDP lung cancer cells. Combined curcumin and DDP treatment markedly inhibited A549/DDP cells proliferation, reversed DDP resistance and triggered apoptotic death by promoting HIF-1α degradation and activating caspase-3, respectively. Expression of HIF-1α-dependent P-gp also seemed to decrease as response to curcumin in a dose-dependent manner. Our findings shed light on drug resistant reversing effect of curcumin in lung cancer cells by inhibiting HIF-1α expression and activating caspase-3.

Curcumin, a yellow pigment derived from Curcuma longa Linn, has attracted great interest in the research of cancer during the past decades. Extensive studies documented that curcumin attenuates cancer cell proliferation and promotes apoptosis in vivo and in vitro. Curcumin has been demonstrated to interact with multiple molecules and signal pathways, which makes it a potential adjuvant anti-cancer agent to chemotherapy. Previous investigations focus on the mechanisms of action for curcumin, which is shown to manipulate transcription factors and induce apoptosis in various kinds of human cancer. Apart from transcription factors and apoptosis, emerging studies shed light on latent targets of curcumin against epidermal growth factor receptor (EGFR), microRNAs (miRNA), autophagy and cancer stem cell. The present review predominantly discusses significance of EGFR, miRNA, autophagy and cancer stem cell in lung cancer therapy. Curcumin as a natural phytochemicals could communicate with these novel targets and show synergism to chemotherapy. Additionally, curcumin is well tolerated in humans. Therefore, EGFR-, miRNA-, autophagy- and cancer stem cell-based therapy in the presence of curcumin might be promising mechanisms and targets in the therapeutic strategy of lung cancer.

Hypoxic pulmonary hypertension is a life-threatening emergency if untreated. Consistent pulmonary hypertension also leads to arteries and ventricular remodeling. The clinical therapeutic strategy for pulmonary hypertension and the corresponding remodeling mainly interacts with NO, angiotensin II (Ang II) and elevated endothelin (ET) targets. In the present study, we evaluated the effects of polydatin on hypoxia-induced pulmonary hypertension. It was observed that polydatin attenuated hypoxic pulmonary hypertension, reversed remodeling, and regulated NO, Ang II, ET contents in the serum and lung samples. However, forced activation of PKC signaling by its selective activator thymeleatoxin (THX) could abate the effects of polydatain. These results suggest that polydatin might be a promising candidate for hypoxic pulmonary treatment through interaction with PKC mechanisms.