Introduction: Prostate cancer is one of the most common cancers threatening public health worldwide. Although chemotherapy plays an important role in treating prostate cancer, it leads to many adverse effects and is prone to drug resistance. Quercetin, a natural product, is used in traditional Chinese medicine because of its strong antitumor activity and few side effects. Methods: In this study, we combined quercetin and paclitaxel to kill prostate cancer cells in vivo and in vitro, and we investigated the relevant mechanism of this combination treatment. After the cancer cells were treated with quercetin or/and paclitaxel, cell growth inhibition, apoptosis, the cell cycle, reactive oxygen species (ROS) generation, and several endoplasmic reticulum (ER) stress signaling pathway related gene expressions were evaluated. Results: The combined treatment with quercetin and paclitaxel significantly inhibited cell proliferation, increased apoptosis, arrested the cell cycle at the G2/M phase, inhibited cell migration, dramatically induced ER stress to occur, and increased ROS generation. In a PC-3 cancer-bearing murine model, this combination treatment exerted the most beneficial therapeutic effects, and quercetin increased the cancer cell-killing effects of paclitaxel, with nearly no side effects compared with the single paclitaxel treatment group. Conclusion: Combination treatment possessed enhanced anti-cancer effects, and these results will provide a basis for treating prostate cancer using a combination of quercetin and paclitaxel.

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare neoplasm. It morphologically resembles papillary thyroid carcinoma and is immunochemically positive for thyroid transcription factor 1. Herein, we reported a case of TL-LGNPPA in a female patient of 35 years old. She felt pharyngeal foreign body sensation of unknown cause and subsequently developed dyspnea after activities. Nasopharyngeal plain computerized tomography showed no abnormalities, but laryngoscopy showed a peanut-sized smooth neoplasm with a pedicel at the posterior edge of the nasal septum. The mass was completely resected by nasopharyngoscopy. Histologic examination showed the tumor was composed of papillary configuration and tubular glands; each papilla was covered with cuboidal or columnar epithelial cells; tubular architecture and spindle cell component were also observed; some tumor cells had psammoma bodies. Immunohistochemically, tumor cells were positive for CKpan, CK7, CK19, VIM, and thyroid transcription factor 1, but negative for thyroglobulin, CK20, S-100, P63, P40, smooth muscle actin, CDX-2, and glial fibrillary acidic protein. This patient was diagnosed with TL-LGNPPA and followed up for 16 months, and metastasis and recurrence were not observed.

Background: Castration-resistant prostate cancer (CRPC) accounts for the majority of prostate cancer deaths, and patients with CRPC are prone to developing drug resistance. Therefore, there is a need to develop effective therapeutics to treat CRPC, especially drug-resistant CRPC. Although various nanoparticles have been developed for drug or gene delivery and control release, approaches to reproducibly formulate the optimal treatment with nanoparticles that could effectively target CRPC and bone metastasis remain suboptimal. Recently, codelivery of a chemotherapeutic agent and a small interfering RNA (siRNA) has become a promising strategy for the treatment of drug-resistant prostate cancer. Methods: In a previous study, we prepared a novel RGD-PEG-DSPE/CaP nanoparticle as an effective and biocompatible drug and gene delivery system. In this study, we further modify the nanoparticle to obtain the LCP-RGD nanoparticle, which contains a calcium phosphate (CaP) core, dioleoyl phosphatidic acid (DOPA) and RGD modified poly(ethylene glycol)-conjugated distearoyl phosphatidylethanolamine (RGD-PEG-DSPE). This drug delivery system was used for codelivery of GRP78 siRNA and docetaxel (DTXL) for the treatment of the PC-3 CRPC. Results: The nanoparticles contain the CaP core, which can effectively compress the negatively charged siRNA, while the DOPA and RGD-PEG-DSPE component can effectively carry DTXL. The arginine-glycine-aspartic acid (RGD) segment can target the prostate cancer site, as the cancer site is neovascularized. This novel nanoparticle has good stability, excellent biocompatibility, high drug and siRNA loading capacity, and an in vitro sustainable release profile. Conclusion: Codelivery of DTXL and GRP78 siRNA has enhanced in vitro and in vivo anti-prostate cancer effects which are much greater than using free DTXL and free GRP78 siRNA together. Our study also indicated that codelivery of DTXL and GRP78 siRNA have an in vitro and in vivo combinational anti-prostate cancer effect and also could effectively sensitize the cell-killing effect of DTXL; this method may be especially suitable for drug-resistant CRPC treatment.

Recently, the transcription factor SOX11 has gained extensive attention as a diagnostic marker in a series of cancers. However, to date, the possible roles of SOX11 in breast cancer has not been investigated. In this study, immunohistochemical staining for SOX11 was performed for 116 cases of breast cancer. Nuclear SOX11 was observed in 42 (36.2%) and cytoplasmic SOX11 in 52 (44.8%) of breast cancer samples. Moreover, high expression of cytoplasmic and nuclear SOX11 was associated with clinicopathological factors, including earlier tumor grade, absence of lymph node metastasis and smaller tumor size. Kaplan-Meier survival curves demonstrated high nuclear SOX11 expression to be associated with more prolonged overall survival than those with low expression and it could be an independent predictor of survival for breast cancer patients. It is worthwhile to note that cytoplasmic SOX11 was not correlated with prognosis of breast cancer patients. These data suggest the possibility that nuclear SOX11 could be as a potential target for breast cancer therapy.