OBJECTIVE: This study was designed to investigate the therapeutic and anti-metastatic potential of the two newly obtained anti-nNav1.5 antibodies, polyclonal anti-nNav1.5 (pAb-nNav1.5) and monoclonal anti-nNav1.5 (mAb-nNav1.5), on breast cancer invasion and metastasis.
METHODS: MDA-MB-231 and 4T1 cells were used as in vitro models to study the effect of pAb-nNav1.5 (59.2 µg/ml) and mAb-nNav1.5 (10 µg/ml) (24 hours treatment) on cell invasion. 4T1-induced mammary tumours in BALB/c female mice were used as an in vivo model to study the effect of a single dose of intravenous pAb-nNav1.5 (1 mg/ml) and mAb-nNav1.5 (1 mg/ml) on the occurrence of metastasis. Real-time PCR and immunofluorescence staining were conducted to assess the effect of antibody treatment on nNav1.5 mRNA and protein expression, respectively. The animals' body weight, organs, lesions, and tumour mass were also measured and compared.
RESULTS: pAb-nNav1.5 and mAb-nNav1.5 treatments effectively suppressed the invasion of MDA-MB-231 and 4T1 cells in the 3D spheroid invasion assay. Both antibodies significantly reduced nNav1.5 gene and protein expression in these cell lines. Treatment with pAb-nNav1.5 and mAb-nNav1.5 successfully reduced mammary tumour tissue size and mass and prevented lesions in vital organs of the mammary tumour animal model whilst maintaining the animal's healthy weight. mRNA expression of nNav1.5 in mammary tumour tissues was only reduced by mAb-nNav1.5.
CONCLUSION: Overall, this work verifies the uniqueness of targeting nNav1.5 in breast cancer invasion and metastasis prevention, but more importantly, humanised versions of mAb-nNav1.5 may be valuable passive immunotherapeutic agents to target nNav1.5 in breast cancer.
METHODS: A prospective study spanning 27 months was conducted at the University Hospital, Kuala Lumpur. Serum CEA (Abbott IMx) and serum squamous cell carcinoma antigen (Abbott IMx) from patients clinically suspected of having primary carcinoma of the lung, were assayed using the microparticle enzyme immunoassay method.
RESULTS: Thirty seven cases of histologically confirmed primary lung carcinoma were studied. Of these, 17 were squamous cell carcinomas, 10 adenocarcinomas, nine small cell carcinomas, and one large cell carcinoma. The patients' ages ranged from 34-82 years. The male:female ratio was 3.6:1. Squamous cell carcinoma antigen was raised above the cutoff value of 1.5 ng/ml in 94.1% of squamous cell carcinomas, 20.0% of adenocarcinomas, and 11.1% of small cell carcinomas. By comparison, CEA was raised above the cutoff value of 3.0 ng/ml in 70.6% of squamous cell carcinomas, 77.8% of small cell carcinomas, and 100% of adenocarcinomas. CEA and squamous cell carcinoma antigen were not raised in the patient with large cell carcinoma and in 14 healthy volunteers. None of 15 patients with a variety of benign lung diseases showed a rise of CEA, while two patients--a 25 year old Indian woman with pneumonia and a 64 year old Malay man with bronchial asthma--had raised squamous cell carcinoma antigen values above the cutoff. Serum CEA and squamous cell carcinoma antigen values did not seem to correlate with stage or degree of differentiation of the tumours.
CONCLUSIONS: The findings suggest that CEA is a good general marker for carcinoma, particularly adenocarcinoma. In contrast, squamous cell carcinoma antigen is more specific for squamous carcinoma.