Long noncoding RNAs (lncRNAs) are the major elements of the mammalian transcriptome that is emerging as a central player controlling diverse cellular mechanisms. Most of the well-studied lncRNAs so far are found to be crucial in regulating cellular processes such as cell cycle, growth, and apoptosis that ensure homeostasis. Owing to their location and distribution in the genome, lncRNAs influence the transcription of a wide range of proteins directly or indirectly by transcriptional and posttranscriptional alterations, which opens up the "LncRNA-cancer paradigm" in a context-dependent manner, i.e., either oncogenic or tumor suppressive. Thus, this chapter is a consolidation of lncRNA association in exhibiting or suppressing the typical cancer hallmarks such as continuous proliferation, surpassing apoptosis, genomic instability, drug resistance, invasion, and metastasis studied till date. In addition, special focus has been given on the efficient application of lncRNAs as potential targets for therapeutics that holds a great promise for future cancer therapy.