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The overexpression of chondroitin sulfate proteoglycan 4 (CSPG4) is associated with several tumor types, including malignant melanoma, squamous cell carcinoma, triple‑negative breast carcinoma, oligodendrocytomas or gliomas. Due to its restricted distribution in normal tissues, CSPG4 has been considered a potential target for several antitumor approaches, including monoclonal antibody (mAb) therapies. The aim of the present study was to characterize the impact of the CSPG4‑specific mAb clone 9.2.27 on its own or in combination with the commonly used BRAF‑selective inhibitor, PLX4032, on different functions of melanoma cells to assess the potential synergistic effects. The BRAF V600‑mutant human melanoma cell lines, M14 (CSPG4‑negative) and WM164 (CSPG4‑positive), were exposed to the CSPG4‑specific 9.2.27 mAb and/or PLX4032. Cell viability and colony formation capacity were evaluated. A 3D‑cell culture spheroid model was used to assess the invasive properties of the treated cells. In addition, flow cytometric analysis of apoptosis and cell cycle analyses were performed. Incubation of the WM164 cell line with CSPG4‑specific 9.2.27 mAb decreased viability, colony formation ability and the invasive capacity of CSPG4‑positive tumor cells, which was not the case for the CSPG4‑negative M14 cell line. Combined treatment of the WM164 cells with 9.2.27 mAb plus PLX4032 did not exert any significant additional effect in comparison to treatment with PLX4032 alone in the clonogenic and invasion assays. M14 cell cycle distribution was not influenced by the CSPG4‑specific 9.2.27 mAb. By contrast, the exposure of WM164 cells to the mAb resulted in an arrest of the cells in the S phase. Moreover, combined treatment of the WM164 cells led to a significantly increased accumulation of cells in the subG1 phase, combined with a decrease of cells in the G2/M phase. On the whole, findings of the present study indicate that the CSPG4‑specific 9.2.27 mAb exerts an anti‑invasive effect on CSPG4‑positive melanoma spheroids, which is not enhanced by BRAF inhibition. These findings provide the basis for further investigations on the effects of anti‑CSPG4‑based treatments of CSPG4‑positive tumors.

H1N1 influenza virus is still regarded as a serious pandemic threat. The most effective method of protection against influenza virus and the way to reduce the risk of epidemic or pandemic spread is vaccination. Influenza vaccine manufactured in a traditional way, though well developed, has some drawbacks and limitations which have stimulated interest in developing alternative approaches. In this study, we demonstrate that the recombinant H1 vaccine based on the hydrophilic haemagglutinin (HA) domain and produced in the yeast system elicited high titres of serum haemagglutination-inhibiting antibodies in mice. Transmission electron microscopy showed that H1 antigen oligomerizes into functional higher molecular forms similar to rosette-like structures. Analysis of the N-linked glycans using mass spectrometry revealed that the H1 protein is glycosylated at the same sites as the native HA. The recombinant antigen was secreted into a culture medium reaching approximately 10 mg/l. These results suggest that H1 produced inPichia pastoriscan be considered as the vaccine candidate against H1N1 virus.