Co-expression in CHO cells of caN-kLC light chain cDNA with each of the four heavy chain isotype cDNAs caN-HCA, caN-HCB, caN-HCC and caN-HCD, produced supernatants containing antibodies “caN-HCA1 + kLC1”, “caN-HCB2 + kLC1”, “caN-HCC1 + kLC1” and “caN-HCD2 + kLC1”, respectively that bound to muNGF equally well by ELISA (Figure 2B). The gene discussed is CNR2; the disease is hepatocellular carcinoma.