Trichinella spiralis (T.spiralis) muscle-larva (ML) excretory–secretory proteins (ESPs) contain antitumour-active substances. ESPs have been shown to inhibit tumour growth. To explore the effects of these proteins on small cell lung cancer cells and the possible mechanisms of their antineoplastic action, H446 SCLC cells were co-cultured with different concentrations of T. spiralis ML ESPs for 12, 24 and 48 h. Our results showed that T. spiralis ML ESPs significantly inhibited H446 cell proliferation, which was dose-and time-dependent. The results of flow cytometry testing indicate a clear apoptosis trend in H446 cells co-cultured with ESPs for 24 h. Reverse transcription polymerase chain reaction and Western blotting results showed increased expression of pro-apoptosis genes Bax, Cyt-C, Apaf-1, caspase-9 and caspase-3, compared with the negative control group, and decreased the expression of anti-apoptosis genes Bcl-2 and Livin. Our results suggest that T. spiralis ML ESPs can induce apoptosis in H446 cells through a mitochondrial pathway, which may be a mechanism of antineoplastic action in T. spiralis ML ESPs.

A 58-year Caucasian woman with a 45-pack year smoking history underwent a computed tomography (CT) scan of the chest due to a persistent respiratory infection. Imaging revealed extensive mediastinal and hilar lymphadenopathy on the right. Fine needle aspiration of the right paratracheal and subcarinal lymph nodes revealed small cell lung carcinoma. She was treated with definitive concurrent chemoradiation (with Cisplatin and Etoposide) therapy to the primary tumor and the mediastinum using intensity modulated radiation therapy. Post-treatment repeat CT of the chest showed complete radiographic response and she was offered prophylactic cranial irradiation which the patient refused. Within six months of completing treatment, the patient developed brain metastases and was treated with a course of palliative radiation to the whole brain. One month after completion, she noticed painful swelling of the left submandibular gland and a CT showed an enlarged submandibular gland. FNA revealed metastatic SCLC. She was treated with urgent palliative RT to the left submandibular gland with significant improvement in her symptoms.