Overview
For the application of our project in real world, it will be developed in three parts. Because our project is about treating colorectal cancer, it is firstly an outline of existing treatments for colorectal cancer, secondly an exploration of our own project's unique audience for some problems specific to China, and finally some ideas for the practical implementation of our drug in the future. We always stick to the initial intention of iGEM: Local people solving local problems, using synthetic biology, everywhere around the world.
Outline of existing treatment methods
In 2018, colorectal cancer (CRC) is the third most common cancer worldwide. The incidence of CRC in China ranks second [1-2]. The incidence of CRC in China is higher than the world. In 2020, there will be more than 1.88 million new CRC patients worldwide [2].
The rising incidence of CRC has also led to an increase in the cost of treatment for colorectal cancer worldwide. It is estimated that colorectal cancer treatment costs in the United States alone are as high as $ 6.5 billion per year [3]. From 1996 to 2015, the annual growth rate of medical expenditure for CRC patients in China was 6.9 % [4].
The current treatment methods include polypectomy, chemotherapy, radiotherapy, combination therapy, immunotherapy, etc. However, each treatment has side effects, and each therapy has disadvantages such as tumor recurrence, lack of specificity of targets, and resistance to anticancer drugs. Therefore, the study of colorectal cancer treatment is worth exploring [5]. We have collated the disadvantages and costs of several colorectal cancer treatment methods that are more commonly used today.
At present, the most important and effective way to treat colorectal cancer is surgical resection. Chemotherapy and radiotherapy are often used as adjuvant therapy, which often comes with serious side effects. Compared to the side effects of these treatments, it is clear that our engineered microbes have fewer side effects and are within an acceptable price range, which is expected to be very promising in the marketplace.
Born in China, Back to China: Our Audiences
As a rapidly developing country, China differs from other countries in its vast size, and although its economy is trending upward, there is still a certain gap between areas. First, from the perspective of China's map, the economic level of the southeastern coastal region is better than that of the northwestern region, and the GDP of some regions can be several times different from each other. The following chart shows a map of China's GDP by province in the first quarter of 2022, as you can see from the colors, there are significant disparities between regions.
Then narrowing the view to a province or a city, there is also a gap between the income of rural areas and urban areas. Take Shanghai and Beijing, two large cities with good economies, for example, the chart below shows the annual income of their rural and urban residents, and you can see that the income is basically double.
From the above two dimensions, it can be seen that there is a certain problem of resource allocation in China, and the same is true for medical resources. Specifically, there is a relationship between GDP and medical resources. When GDP per capita is less than 20,000 yuan, the level of equalization of medical resource allocation between regions and urban and rural areas in each province increases with economic development, while the efficiency of medical system resource allocation in each province decreases. When the GDP per capita is less than 40,000 yuan and more than 20,000 yuan, the level of equalization of medical resource allocation between regions and urban/rural areas in each province decreases with economic development, while the allocation efficiency increases with the level of economic development. When the GDP per capita is greater than 40,000 yuan, the equalization and efficiency of medical resource allocation in each province's medical system increases [6].
In terms of treatment costs, the choice of treatment method for CRC patients was not associated with patient gender and age (P=0.93 and P=0.10), while treatment cost was significantly associated with treatment method (P < 0.001).The median treatment costs in the chemotherapy, radiotherapy, chemoradiotherapy and palliative care groups were ¥49,336.40, ¥43,226.50, ¥76,148.11 and ¥14,078.62, respectively, with significantly higher median costs in the chemotherapy group than in the radiotherapy group [7]. But there is no cheap option among them.
Long-term treatment not only brings financial burden, but also spiritual, the prevalence of depressive symptoms after a CRC diagnosis was 23.8% [8]. It is likely to be more probable when disaster strikes rural families in remote areas, where medical care is not well developed and access to good medical care requires long travel.
So that's the problem we can solve with engineered probiotics: high price and lack of access to good medical care. The price of the drug is not only much lower than traditional treatment methods, but also does not require patients to travel long distances to the hospital on a regular basis, and only requires a certain amount of medication to be taken within a regular period of time, as well as less psychological burden. We practice the goal of iGEM: Local people solving local problems, using synthetic biology, everywhere around the world.
Future Prospects
As mentioned above, our products are marketable and go some way to solving the resource inequality problem in China.
Our engineered probiotics to work in anticipation of entering the market in the final form of capsules, and we are also experimenting with capsule coating, more details can visit hardware and partnership.
Because we have not conducted animal experiments, we do not know the actual effect in the intestinal tract, and even if clinical trials are conducted later, the side effects of probiotic drugs will take some time to manifest. According to the research, microorganisms used as probiotics may cause systemic infections, stimulate the immune system and disturb metabolism [9]. Therefore, we intend to introduce our drug into the market as a prescription drug, which means it must be prescribed by a clinician before purchasing in the pharmacy and must be used under the guidance of a licensed pharmacist. To ensure our follow-up plan goes smoothly, we also interviewed the Gansu Provincial Medical Products Administration to understand the procedures and laws and regulations that need to be followed to market probiotic drugs in China, more details can visit integrated HP-government
Based on the aforementioned lack of medical resources for people in some remote areas, we intend to start working with hospitals in the northwest and then gradually expand the range. Also, due to the side effects of probiotics, we ask hospitals to conduct allergen tests on patients before prescribing them to ensure that the side effects are minimized.
Based on our questionnaire to the general public, we found that the public don't familiar with gene editing technology and there is some controversy about the operation of genetic modification, more details can visit integrated HP-public. We concerned that the patients will be resistant to taking gene-edited probiotics to treat their own diseases. In addition, CRC is considered a disease in older adults, with average age of onset at 50 years or older [10]. Whereas most elderly people would prefer traditional treatments, in view of this situation, we would like to offer our probiotics as an adjunctive treatment. Patients can choose whether to take it or not according to their level of understanding and trust in gene editing.
References
[1] Bray F,Ferlay J,Soerjomataram I,et al.Global cancer statistics 2018:GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries[J].CA:a Cancer Journal for Clinicians, 2018, 68(6):394-424.
[2] Siegel RL,Miller KD,Goding Sauer A,et al.Colorectal cancer statistics,2020[J].CA:a Cancer Journal for Clinicians,2020,70(3):145-164.
[3] Banerjee A,Pathak S,Subramanium VD,et al.Strategies for targeted drug delivery in treatment of colon cancer: current trends and future perspectives[J].Drug Discov Today,2017,22(8):1224-1232.
[4] Xue Siqi,He Jing,Tang Yong.Research progress in the treatment of colon cancer [J].Chinese Medical Sciences,2022,12(09):58-61.
[5] Engstrand J,Nilsson H,Strömberg C,et al.Colorectal cancer liver metastases-a population-based study on incidence,management and survival[J].Bmc Cancer,2018,18(1):78.
[6] Jing Huo. (2011). Research on the allocation of health care resources in China from an economic perspective (Master's thesis, Ningbo University).
[7] Li QC, Jiang Q, Chen X, Guo XIR. Study on the economic burden of clinical treatment for colorectal cancer patients[J]. Journal of Clinical Pharmacotherapy,2021,19(07):65-70.
[8] Varela-Moreno, E, Rivas-Ruiz, F, Padilla-Ruiz, M, et al. Influence of depression on survival of colorectal cancer patients drawn from a large prospective cohort. Psychooncology. 2022; 1- 12.
[9] ZAWISTOWSKA-ROJEK,A. & TYSKI,S.(2018).Are Probiotic Really Safe for Humans?. Polish Journal of Microbiology,67(3) 251-258.
[10] Garg, R., Cheng, V., Ellis, U. et al. Direct medical costs of young-onset colorectal cancer: a worldwide systematic review. BMC Health Serv Res 22, 1100 (2022).