Lung cancer is the leading cause of cancer-related deaths in the world with non-small cell lung cancer (NSCLC) making up a large majority of all cases. Despite advancement and discoveries in cancer therapy, treatment of this disease has been less successful due to serious side effects and drug resistance. Therefore, there is a need to research into new therapeutic approaches for this disease. This study, therefore, evaluated the effect of two common cytotoxic lung cancer drugs, the etoposide and cisplatin on two lung cell lines, A549 (lung cancer cell line) and BEAS-2B (normal lung virus-transformed cell line). Our study was aimed at testing the response of normal lung and lung cancer cells to different concentrations of etoposide and cisplatin over a period of time in order to determine the cytotoxic effect of these drugs. The cells were grown in culture plates and MTT assays were performed on both cell lines in order to determine each cell line's IC50 in response to various concentrations of cisplatin and etoposide over a maximum period of 72 hrs. Our results showed a cytotoxic effect on both cell lines. Unexpectedly, higher drug toxicity was observed on BEAS-2B compared to A549 cell lines. Consequently, this data highlights the necessity for further search of a more selective and effective drug that has minimal toxicity on the normal cells for effective treatment of NSCLC and lung cancer in general.

Immunohistochemistry (IHC) technique is one of the antigen-antibody techniques that has added advantage of providing an on-site information in an intact tissue, thus its preferred adoption for diagnosis in the management and treatment of chronic diseases such as COPD and lung cancer. The use of IHC technique has been shown to be very useful in expressing tumour suppressor genes such as p53, particularly in studies for lung carcinogenesis. This study isaimed at carrying out preliminary IHC optimisation for the following tumour suppressor genes; p53, TTC5, Bax and p21 genes on COPD tissue sections, in order to arrive at optimum IHC staining condition and antibody concentrations as part of larger studies on understanding the role of these genes in lung carcinogenesis and consequently, finding better therapy for lung cancer. Several IHC staining using the avidin-biotin complex kit (ABC) were carried out to express the four genes using different staining conditions and different primary antibody dilutions. Our study revealed high-level expression of the four tumour suppression genes on COPD tissue sections with 1:250, 1:500 1:500 and 1:100 optimum primary antibody dilutions for p53, TTC5, Bax and p21 genes respectively. All experiments for optimum results were carried out under 21 ⁰ C room temperature, as higher background staining was seen to be associated with higher environmental staining temperature. These findings revealed an active DNA damage response, even though we are still far from understanding the current function of p53 and its downstream genes in this particular tissue.