It would be better if you can get a normal lung cells rather than using HEK293. Some reviewer if you are publishing or thesis writing might scrutinize your use of that cells although both epithelial cell lines. 

Are you looking for cells to which you can compare your results in lung cancer cells? If I were reviewing your paper, I would not accept HEK293 as an appropriate control, if for no other reason than because they are a cell line, and secondly, because they are kidney cells. You can purchase proper primary cultures from Lonza. See here: http://www.lonza.com/products-services/bio-research/primary-cells/human-cells-and-media/airway-cells-and-media.aspx You can only use these for a finite number of passages. From the above-mentionned link, you can purchase airway epithelium and endothelium, as well fibroblasts, and smooth muscle cells. If limited to one, I would choose the bronchial epithelial cells since you are comparing to cancer cells of epithelial origin. If your lab is not able to afford the cells, perhaps you can find an early passage of similar cells from a collaborator, or failing that, from someone who has published work studying the same cells.

I strongly recommend to use normal lung cells, if you use HEK293 your results would be biased.

Please use normal lung cells!  Comparing carcinoma with epithelium. Otherwise what is the reason to do such study?

Thanks for your valuable suggestions @ Reagan Entigu & Ashley L Hilchie.

thanks a lot for your valuable suggestions professor Rajalakshmanan Eswaramoorthy.

Thank you so much for taking the time from your busy schedule to write a suggestion to me professor Jacques Gilloteaux.

I was not able to get normal lung cells in India. And i was requesting normal lung cells from the recently published researchers by mail.

I am surprised that with all the monies spent for research and the spatial and atomic research, your country should not have some funds, especially dealing with research about pollution of the air in New Delhi!