**2. Long period run in research and development in pharmacy**

The development of drugs is based on the determination of new therapeutic targets, the pharmacological receptors. This concept was first proposed by Paul

Ehrlich in 1908 [5]. Normal cells replicate their DNA with great accuracy, but cancer has a large number of mutations that show up in cancer cells that make them pharmacological targets [6]. From the initial concept of molecular targets, drug targets were discovered and validated, which successful translated the most drugs into practice [7].

**5. What can data tell us?**

*DOI: http://dx.doi.org/10.5772/intechopen.89976*

**pancreatic cancer**

than 10 months.

*NCCN Recommend: National Comprehensive Cancer Network.*

*Potential biomarkers used in advanced pancreatic cancer.*

**Table 1.**

**131**

Total, there are 18 biomarkers used among these results. For details please see **Table 1**. The results from 27 clinical trials could be divided into three categories (a) rank of the effectiveness (b) rank of intervention and (c) quality of life improved.

Total, we found 10 publications where the author declares the successful outcome on the treatment of APC from 2011 to 2019, **Table 2**. These clinical trials recruited 1080 patients with APC (611 male and 469 female). The average overall survival month is 11.62 and progress-free survival month is 10.79. Briefly, Lutz et al. tests the GVAX pancreatic cancer vaccine via GPI biomarkers The OS and PFS approach got the highest point, 24.8 and 17.3, respectively Similarly, Phan et al. tested the pazopanib hydrochloride via VEGF biomarkers. This approach had a higher OS and PFS points. Survival months are 25 and 14.4. Furthermore, Hong et al. disclosed the capecitabine may put the OS and PFS to 17.3 and 10.4 survival months; the remain studies presented similar results, the OS and PFS were lower

**Biomarkers Abbreviation** Vascular endothelial growth factor\* VEGF Thymidine phosphorylase TP Epidermal growth factor receptor\* EGFR Tumor necrosis factor α TNF-α Topoisomerase I inhibitor TIH Sonic hedgehog SHH Severe hypoxia intracellular reductases SHIR Secreted protein acid rich in cysteine SPARC Platelet-derived growth factor PDGF MEK1/2-dependent effector proteins ERK1/2 Kirsten rat sarcoma viral oncogene homolog\* KRAS Interleukin 6/interleukin 8 IL-6/IL-8 Heat shock protein 27 Hsp27 Glycosyl-phosphatidylinositol GPI Double-strand breaks in DNA — Checkpoint kinase 1 CHK1 Microtubule-associated protein light chain 3- II LC3- II Circulating free DNA cfDNA Dihydropyrimidine dehydrogenase DPD

**5.1 Estimation of clinical trials with success outcome on advanced**

*What Are the New Challenges of the Current Cancer Biomarkers?*

Excellent and reliable targets identification and validation can increase the credibility of the relationship between intentions and diseases, this may strength the effectively of drugs. Drugs are usually developed only when specific drug target for the action of these drugs are analyzed and examined. Sufficient potential targets have been discovered rapidly for the drug discovery process.

Numerous data including identified gene and drug discovery cycles have been generated exponentially. This may forge the difficultness in decision making and becomes more and more difficult for drug R&D. Thanks to rapid bioinformatic discoveries, more and more biopharmaceutical targets can be identified and analyzed [8].

Validation from cross-species a bioeffect is performed after the drug target is determined and verified. Rodents and non-human primates provide appropriate animal models for screening and evaluation of a new drug. Most of current cancer in vivo experiments use rodent experimental animals such as mice and rats. Because they are small, rapid reproduction, clear genetic background and mature genetic modification technology can be done. However, due to the distant relationship between rodents and humans, many of the results obtained from rodent models cannot be reproduced in humans. Moreover, non-human primates are highly similar to humans in terms of genetic evolution, immunity, physiology and metabolism. They are theoretically more suitable for cancer researches [9].

Clinical trials are the best channel to tie up pharmaceutical targets to reliable drugs. The goal is to determine whether a candidate drug is safe and effective. There are four phases in clinical trials. More specific biomarker studies are based on data from prospective studies [10]. In the study of cancer biomarkers, retrospective studies and prospective studies help to identify potential biomarkers, which may be validated in the future studies, however, the reliability of evidence remains controversial.

#### **3. Can we trust the current biomarkers of cancer?**

Unfortunately, the overall survival of APC patients has not revised assuredly. There are too many choices in clinical practice and evidence-based medicine is a permanent challenge. Which of the modern biomarkers is reliable? Are we ever going to detect precise pharmaceutical targets on APC [11]?

#### **4. Validation method**

In order to clarify this question, we collected the raw data source (http://clinica ltrials.gov) and searched all the drug treatments on APC. We refined all the data which had results and were published. Briefly, a total of 2726 recordings were found since May 2019. Hundred and fifteen recordings which finished clinical trials, further we ruled out irrelevant 32 recordings and 56 unclear results. Finally, 27 recordings kept comprising the following three tables. Raw data are free, please follow the link 10.6084/m9.figshare.8275190.
