An agent for use in the treatment of glioma in a subject by interfering with tumor microtube -mediated (a) invasion and/or (b) proliferation and/or (c) intracellular communication and/or (d) resistance to radiotherapy and/or chemotherapy of glioma cells, wherein said agent is selected from the group consisting of: an agent that is capable of mediating RNA interference (RNAi) for the specific knockdown of the growth associated protein 43 gene, wherein said agent is selected from the group consisting of small inhibitory RNAs (siRNAs), microRNAs (miRNAs), small hairpin RNAs (shRNAs), antisense oligonucleotides, and antisense RNAs (asRNAs), and wherein said agent is targeted at one of the nucleic acid sequences laid out in SEQ ID NOs: 1 to 5; an agent that is capable of mediating RNA interference (RNAi) for the specific knockdown of the growth associated protein 43 gene, wherein said agent is a DNA antisense oligonucleotide (asDNA) comprising one of the nucleic acid sequences laid out in SEQ ID NOs: 6 to 8, or an asRNA comprising one of the nucleic acid sequences laid out in SEQ ID NOs: 9 to 11; (b) a compound that is capable of inhibiting the biological activity of GAP43 protein, wherein said compound is an antibody, antibody fragment or antibody mimetic specifically binding to GAP43 protein; (c) an agent that is capable of mediating RNAi for the specific knockdown of the human tweety homologue 1 (Ttyh1) gene, wherein said agent is selected from the group consisting of small inhibitory RNAs (siRNAs), microRNAs (miRNAs), small hairpin RNAs (shRNAs), antisense oligonucleotides, and antisense RNAs (asRNAs), and wherein said agent is targeted at one of the nucleic acid sequences laid out in SEQ ID NOs: 12 to 16; (d) a compound that is capable of inhibiting the biological activity of TTYH-1 protein, wherein said compound is an antibody, antibody fragment or antibody mimetic specifically binding to TTYH-1 protein; (e) an agent that is capable of mediating RNA interference (RNAi) for the specific knockdown of the connexin 43 gene, wherein said agent is selected from the group consisting of small inhibitory RNAs (siRNAs), microRNAs (miRNAs), small hairpin RNAs (shRNAs), antisense oligonucleotides, and antisense RNAs (asRNAs), and wherein said agent is targeted at the nucleic acid sequence laid out in SEQ ID NO: 21; a compound that is capable of inhibiting the biological activity of connexin 43, wherein said compound is an antibody, antibody fragment or antibody mimetic specifically binding to and/or functionally blocking Cx43; and a compound that is capable of inhibiting the biological activity of connexin 43, wherein said compound is selected from the group consisting of gap junction blocking peptide Gap 26 (SEQ ID NO: 17); gap junction blocking peptide Gap 27 (SEQ ID NO: 18); glycyrrhetinic acid; quinine; anandamide; octanol; heptanol; anthranilic acid; fenamic acid; retinoic acid; and tonabersat. an agent that is capable of mediating RNA interference (RNAi) for the specific knockdown of the growth associated protein 43 gene, wherein said agent is selected from the group consisting of small inhibitory RNAs (siRNAs), microRNAs (miRNAs), small hairpin RNAs (shRNAs), antisense oligonucleotides, and antisense RNAs (asRNAs), and wherein said agent is targeted at one of the nucleic acid sequences laid out in SEQ ID NOs: 1 to 5; an agent that is capable of mediating RNA interference (RNAi) for the specific knockdown of the growth associated protein 43 gene, wherein said agent is a DNA antisense oligonucleotide (asDNA) comprising one of the nucleic acid sequences laid out in SEQ ID NOs: 6 to 8, or an asRNA comprising one of the nucleic acid sequences laid out in SEQ ID NOs: 9 to 11; (b) a compound that is capable of inhibiting the biological activity of GAP43 protein, wherein said compound is an antibody, antibody fragment or antibody mimetic specifically binding to GAP43 protein; (c) an agent that is capable of mediating RNAi for the specific knockdown of the human tweety homologue 1 (Ttyh1) gene, wherein said agent is selected from the group consisting of small inhibitory RNAs (siRNAs), microRNAs (miRNAs), small hairpin RNAs (shRNAs), antisense oligonucleotides, and antisense RNAs (asRNAs), and wherein said agent is targeted at one of the nucleic acid sequences laid out in SEQ ID NOs: 12 to 16; (d) a compound that is capable of inhibiting the biological activity of TTYH-1 protein, wherein said compound is an antibody, antibody fragment or antibody mimetic specifically binding to TTYH-1 protein; (e) an agent that is capable of mediating RNA interference (RNAi) for the specific knockdown of the connexin 43 gene, wherein said agent is selected from the group consisting of small inhibitory RNAs (siRNAs), microRNAs (miRNAs), small hairpin RNAs (shRNAs), antisense oligonucleotides, and antisense RNAs (asRNAs), and wherein said agent is targeted at the nucleic acid sequence laid out in SEQ ID NO: 21; a compound that is capable of inhibiting the biological activity of connexin 43, wherein said compound is an antibody, antibody fragment or antibody mimetic specifically binding to and/or functionally blocking Cx43; and a compound that is capable of inhibiting the biological activity of connexin 43, wherein said compound is selected from the group consisting of gap junction blocking peptide Gap 26 (SEQ ID NO: 17); gap junction blocking peptide Gap 27 (SEQ ID NO: 18); glycyrrhetinic acid; quinine; anandamide; octanol; heptanol; anthranilic acid; fenamic acid; retinoic acid; and tonabersat.