CN115304603B

CN115304603B - Preparation and application of quinazoline inhibitor

Info

Publication number: CN115304603B
Application number: CN202110496041.4A
Authority: CN
Inventors: 梁永宏
Original assignee: Yaoya Technology Shanghai Co ltd
Current assignee: Yaoya Technology Shanghai Co ltd
Priority date: 2021-05-07
Filing date: 2021-05-07
Publication date: 2024-04-09
Anticipated expiration: 2041-05-07
Also published as: CN115304603A

Abstract

The present invention relates to KRAS ^G12C The invention provides a compound shown in a formula (I), wherein each substituent is defined in the specification. Furthermore, to compositions of the inhibitors and to their use. The compound has good activity of inhibiting tumor growth. And has good safety.

Description

Preparation and application of quinazoline inhibitor

Technical Field

The invention belongs to the field of drug synthesis, and in particular relates to a novel KRAS ^G12C Inhibitors, and methods of making and using the same.

Background

The present invention relates generally to novel compounds, methods for their preparation and use as KRAS ^G12C Use of an inhibitor (e.g. for the treatment of cancer).

RAS represents a closely related group of monomeric globular proteins of 189 amino acids (molecular weight 21 kDa) that are associated with the plasma membrane and bind GDP or GTPoRAS as molecular switches. When the RAS contains bound GDP, it is in a quiescent or off state, and in an "inactive state". In response to exposure of the cells to certain growth-promoting stimuli, the RAS is induced to convert its bound GDP to GTP. After binding to GTP, the RAS is "turned on" and is able to interact with and activate other proteins (its "downstream targets"). RAS proteins themselves have very low intrinsic ability to hydrolyze GTP back to GDP, thus placing themselves in an off state. Turning off the RAS requires an external protein called GTPase Activating Proteins (GAPs), which interact with the RAS and greatly accelerate the conversion of GTP to GDP. Any mutation in the RAS that affects its ability to interact with GAP or convert GTP back to GDP will result in an extended activation time of the protein, thus resulting in an extended cell signal that allows it to continue to grow and divide. Since these signals lead to cell growth and division, the hyperactive RAS signals may ultimately lead to cancer.

Structurally, the RAS protein comprises a G domain responsible for enzymatic activity of the RAS-guanosine nucleotidic binding and hydrolysis (GTPase reaction). It also contains a C-terminal extension called a CAAX box, which can be post-translationally modified and is responsible for targeting proteins to the membrane. The G domain is about 21-25kDa in size and comprises a phosphate binding ring (P-ring). The P-loop is the pocket in which the nucleic acid binds in the protein, which is a rigid part of the domain with conserved amino acid residues ((glycine 12, threonine 26 and lysine 16)) that is essential for nucleic acid binding and hydrolysis. The G domain also contains so-called Switch I (residues 30-40) and Switch II (residues 60-76) regions, both of which are dynamic parts of the protein, which are commonly referred to as "spring loaded" mechanisms as they are capable of switching between resting and loaded states. The key interaction is the hydrogen bond formed by threonine 35 and glycine 60, the Y-phosphate with GTP, which keeps the Switch1 and Switch2 regions in their active conformation, respectively. After GTP hydrolyses and releases phosphate, the two relax to an inactive GDP conformation.

The most well known members of the RAS subfamily are HRAS, KRAS and NRAS, mainly because of their association with multiple types of cancer. Any mutation in any of the three major isoforms of the RAS (HRAS, NRAS or KRAS) gene is the most common in human tumorigenesis. About 30% of human tumors were found to carry RAS gene mutations o notably, KRAS mutations were detected in 25-30% of tumors. In contrast, the oncogenic mutation rates occurring in NRAS and HRAS family members are much lower (8% and 3%, respectively). The most common KRAS mutations were found at residues G12 and G13 and residue Q61 of the P loop. G12C is a frequent mutation of the KRAS gene (glycine 12 to cysteine). Such mutations have been found in about 13% of the occurrences of cancer, about 43% of the occurrences of lung cancer, and about 100% of MYH-related polyposis (familial colon cancer syndrome).

As a leading edge target, KRAS ^G12C Muteins have received a great deal of attention. Araxes (Wellspring subsidiary) developed ARS-853 and ARST620 compounds in 2013 and 2016, respectively. In recent years, it has also been KRAS ^G12C Inhibitors have been applied for several patents, such as W02016164675 and W02016168540, and MRS-853 compounds show good cell viability but their pharmacokinetic properties are poor, which is not suitable for assessing pharmacodynamics of animal models in vivo. Ars-1620 vs KRAS ^G12C Has high efficiency and selectivity, and can realize rapid and continuous target effect in vivo, thereby inducing tumor regression. The in vivo evidence provided by this study suggests that ARS-1620 represents a new generation of KRAS ^G12C Specific inhibitors have great therapeutic potential. Wellspring announces the FDA approved IND application for ARS-3248. Other candidate KRAS ^G12C Inhibitors include MRTX-849 from Mirati corporation and BI-2852 from Boehringer Ingelheim, among others. Thus, although already thereAdvances are made in the individual fields, but there remains a need in the art for improved compounds and methods for treating cancer, for example, by inhibiting KRAS, HRAS or NRAS. The present invention meets this need and provides other related advantages.

Briefly, the present invention provides compounds, including stereoisomers, pharmaceutically acceptable salts, tautomers and prodrugs thereof, capable of modulating G12C mutant KRAS, HRAS and/or NRAS proteins. In some cases, the compound acts as an electrophile capable of forming a covalent bond with a cysteine residue at the 12 position of a KRAS, HRAS or NRAS G12C mutein. Methods of using such compounds for treating various diseases or conditions, such as cancer, are also provided.

Disclosure of Invention

A compound having the general formula (I), a stereoisomer, a pharmaceutically acceptable salt, a polymorph or an isomer thereof, wherein the compound of the general formula (I) has the structure:

wherein,

each X is ₁ Independently at each occurrence selected from N, CR ₅ ；

Each R ₁ And R is ₄ Independently at each occurrence selected from deuterium, halogen, oxo, -C _1-6 Alkyl, -C _2-6 Alkenyl, -C _2-6 Alkynyl, -C _1-6 Alkylene- (halogen) _1-3 、C _1-6 Heteroalkyl, -CN, -OR ₆ 、-C _1-6 Alkylene- (OR) ₆ ) _1-3 、-O-C _1-6 Alkylene- (halogen) _1-3 、-SR ₆ 、-S-C _1-6 Alkylene- (halogen) _1-3 、-NR ₆ R ₇ -C1-6 alkylene-NR ₆ R ₇ 、-C(＝O)R ₆ 、-C(＝O)OR ₆ 、-OC(＝O)R ₆ 、-C(＝O)NR ₆ R ₇ 、-NR ₆ C(＝O)R ₇ 、-S(O) ₂ NR ₆ R ₇ or-C _3-6 Carbocyclyl; each R ₁₂ Independently optionally substituted with 1, 2, 3, 4, 5 or 6 groups selected from deuterium, halogen, -C _1-6 Alkyl, -C _1-6 Alkoxy, oxo, -OR ₆ 、-NR ₆ R ₇ 、-CN、-C(＝O)R ₆ 、-C(＝O)OR ₆ 、-OC(＝O)R ₆ 、-C(＝O)NR ₆ R ₇ 、-NR ₆ C(＝O)R ₇ or-S (O) ₂ NR ₆ R ₇ Substituted or unsubstituted;

R ₂ ，R ₃ and R is ₅ Independently selected from H, D, cyano, halogen, C _1-6 Alkyl group COOH, NHCOH, CONH ₂ OH or-NH ₂ ；

U is independently selected from-C _0-4 Alkyl-, -CR ₈ R ₉ -、-C _1-2 Alkyl (R) ⁸ )(OH)-、-C(O)-、-CR ₈ R ₉ O-、-OCR ₈ R ₉ -、-SCR ₈ R ₉ -、-CR ₈ R ₉ S-、-NR ₈ -、-NR ₈ C(O)-、-C(O)NR ₈ -、-NR ₈ C(O)NR ₉ -、-CF ₂ -、-O-、-S-、-S(O) _m -、-NR ₈ S(O) _m -、-S(O) _m NR ₈ -；

Y is absent or C is selected _3-8 Cycloalkyl, 3-8 membered heterocycloalkyl, 5-12 membered fused alkyl, 5-12 membered fused heterocyclyl, 5-12 membered spiroheterocyclyl, aryl or heteroaryl, wherein said cycloalkyl, heterocycloalkyl, spiroheterocyclyl, fused ring, fused heterocyclyl, spiroheterocyclyl, aryl or heteroaryl is optionally substituted with one or more G ¹ Substituted;

z is independently selected from cyano, -NR ₁₀ CN、

Bond c is a double bond or a triple bond;

when c is a double bond, R ^a 、R ^b And R is ^c Each independently selected from H, deuterium, cyano, halogen, C _1-6 Alkyl, C _3-6 Cycloalkyl or 3-6 membered heterocyclyl. Wherein said alkyl, cycloalkyl and hetero-groupsThe cyclic groups optionally being substituted by 1 or more G' s ² Substituted;

R ^a and R is ^b Or R is ^b And R is ^c Optionally together with the carbon atoms to which they are attached form a 3-6 membered ring optionally containing heteroatoms;

when bond c is a triple bond, R ^a And R is ^c Absent, R ^b Independently selected from H, deuterium, cyano, halogen, C _1-6 Alkyl, C _3-6 Cycloalkyl or 3-6 membered heterocyclyl groups substituted by one or more G ³ Substituted;

R ₁₀ independently selected from H, deuterium, C _1-6 Alkyl, C _3-6 Cycloalkyl or 3-6 membered heterocyclyl, wherein the alkyl, cycloalkyl and heterocyclyl are optionally substituted with 1 or more G ⁴ Substituted;

G ¹ 、G ² 、G ³ and G ⁴ Each independently selected from deuterium, cyano, halogen, C _1-6 Alkyl, C _2-6 Alkenyl, C _2-6 Alkynyl, C _3-8 Cycloalkyl or 3-8 membered heterocyclyl, C _6-10 Aryl, 5-10 membered heteroaryl, -OR ₁₁ 、-OC(O)NR ₁₁ R ₁₂ 、-C(O)OR ₁₁ 、-C(O)NR ₁₁ R ₁₂ 、-C(O)R ₁₁ 、-NR ₁₁ R ₁₂ 、-NR ₁₁ C(O)R ₁₂ 、-NR ₁₁ C(O)NR ₁₂ R ₁₃ 、-S(O) _m R ₁₁ or-NR ₁₁ S(O) _m R ₁₂ Wherein the alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl are optionally substituted with 1 or more deuterium, cyano, halogen, C _1-6 Alkyl, C _2-6 Alkenyl, C _2-6 Alkynyl, C _3-8 Cycloalkyl or 3-8 membered heterocyclyl, C _6-10 Aryl, 5-10 membered heteroaryl, -OR ₁₄ 、-OC(O)NR ₁₄ R ₁₅ 、-C(O)OR ₁₄ 、-C(O)NR ₁₄ R ₁₅ 、-C(O)R ₁₄ 、-NR ₁₄ R ₁₅ 、-NR ₁₄ C(O)R ₁₅ 、-NR ₁₄ C(O)NR ₁₅ R ₁₆ 、-S(O) _m R ₁₄ or-NR ₁₄ S(O) _n R ₁₅ Is substituted by a substituent of (2); r is R ⁸ 、R ⁹ 、R ¹¹ 、R ¹² 、R ¹³ 、R ¹⁴ And R is ¹⁵ Each independently selected from hydrogen, deuterium, cyano, halogen, C _1-6 Alkyl, C _3-8 Cycloalkyl or 3-8 membered monocyclic heterocyclyl, monocyclic heteroaryl or phenyl;

and m is 1 or 2.

In some embodiments, the compound of formula (I) or an isomer, solvate or precursor thereof, or a pharmaceutically acceptable salt thereof, is selected from the following compounds, isomers, solvates or precursors thereof, or pharmaceutically acceptable salts thereof:

in another aspect, the present invention also provides a pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable adjuvant.

In another aspect, the invention relates to a method of treating a KRAS G12C-associated disease in a mammal comprising administering to a mammal, preferably a human, in need of such treatment a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition thereof.

In another aspect, the present invention relates to the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for the prevention or treatment of KRAS G12C-related diseases.

In another aspect, the present invention relates to a compound of formula (I) or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition thereof, for preventing or treating KRAS G12C-related diseases.

Detailed description of the preferred embodiments

The invention also provides a method for preparing the compound. The preparation of the compounds of the general formula (I) according to the invention can be carried out by the following exemplary methods and examples, which, however, should not be regarded as limiting the scope of the invention in any way. The compounds of the present invention may also be synthesized by synthetic techniques known to those skilled in the art, or by a combination of methods known in the art and methods described herein. The product obtained in each step is obtained using separation techniques known in the art including, but not limited to, extraction, filtration, distillation, crystallization, chromatographic separation, and the like. The starting materials and chemical reagents required for the synthesis can be synthesized conventionally according to the literature (reaxys) or purchased.

Unless otherwise indicated, temperatures are degrees celsius. Reagents were purchased from commercial suppliers such as chemlocks Inc, astatech Inc or michelin and these reagents were used directly without further purification unless otherwise indicated.

Unless otherwise indicated, the following reactions were carried out at room temperature, in anhydrous solvents, under positive pressure of nitrogen or gas, or using dry tubes; glassware drying and/or heat drying.

Column chromatography purification uses 200-300 mesh silica gel from the Qingdao marine chemical plant unless otherwise indicated; preparation of thin layer chromatography A thin layer chromatography silica gel prefabricated plate (HSGF 254) manufactured by Kagaku chemical industry research institute of tobacco, inc.; MS was determined using a Therno LCD Fleet type (ESI) liquid chromatograph-mass spectrometer.

Nuclear magnetic data (1H NMR) using Bruker Avance-400MHz or Varian Oxford-400Hz nuclear magnetic instruments, the solvent used for the nuclear magnetic data was CDCl ₃ 、CD ₃ OD、D ₂ O, DMS-d6, etc., based on tetramethylsilane (0.000 ppm) or on residual solvent (CDCl) ₃ :7.26ppm；CD ₃ OD:3.31ppm；D ₂ O4.79 ppm; d6-DMSO:2.50 ppm) when peak shape diversity is indicated, the following abbreviations indicate the different peak shapes: s (singlet), d (doublet), t (triplet), q (quartet), m (multiplet), br (broad), dd (doublet), dt (doublet). If the coupling constant is given, it is in Hertz (Hz).

Example 1

7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -4-propenoyl-2-methylpiperazin) -1-yl) -2- (((2R, 7 as) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline

The first step: preparation of 7-bromo-8-fluoro-2, 4-quinazolinedione

3-fluoro-4-bromo-2-aminobenzoic acid (11.7 g,0.05 mol) and urea (45 g,0.75 mol) were heated to 150℃and reacted for 12 hours with stirring, then cooled to 95℃and then 200mL of water was added, stirred for half an hour for filtration, slurried with acetic acid and then dried to give 7-bromo-8-fluoro-2, 4-quinazolindione (11.88 g, 87%) as a pale yellow solid.

LC/MS(ESI):m/z＝274[M+H] ⁺ .

And a second step of: preparation of 7-bromo-8-fluoro-2, 4-dichloroquinazoline

7-bromo-8-fluoro-2, 4-quinazolinedione (10.92 g 40 mmol) was dissolved in POCl ₃ To (100 mL) was added a small amount of N, N-dimethylaniline, and the mixture was heated under reflux with stirring for 10 hours. Then pouring into ice water for quenching, filtering to obtain a solid product, washing with water, and drying to obtain crude yellow solid 7-bromo-8-fluoro-2, 4-dichloroquinazoline 1f (9.94 g, 84%) which is used for the next reaction without further purification.

LC/MS(ESI):m/z＝297[M+H] ⁺ .

And a third step of: preparation of 2-chloro-7-bromo-8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) quinazoline

7-bromo-8-fluoro-2, 4-dichloroquinazoline (1.18 g,4 mmol), (R) -4-Boc-2-methylpiperazine (0.88 g,4.4 mmol), potassium carbonate (0.88 g,6.4 mmol) catalytic amounts of potassium iodide and DMF (80 mL) were mixed, heated to 120℃and reacted with stirring for 4 hours. Cooled to room temperature and evaporated under reduced pressure to give 1g (1.51 g, 82%) of 2-chloro-7-bromo-8-fluoro-4- (((R) -4-boc-2-methylpiperazine) -1-yl)) quinazoline as a yellow solid,

LC/MS(ESI):m/z＝460[M+H] ⁺ 。

fourth step: preparation of 6-chloro-7-bromo-8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) -2- (((2R, 7 aS) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline

2-chloro-7-bromo-8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) quinazoline (275 mg,0.6 mmol), (2R, 8S) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methanol (106 mg,0.66 mmol), potassium carbonate (124 mg,0.90 mmol) as a catalytic amount of potassium iodide and DMF (20 mL) were mixed, heated to 120℃and reacted with stirring for 4 hours. Cooled to room temperature, evaporated under reduced pressure and purified by column chromatography to give 7-bromo-8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl) -2- (((2R, 7 as) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline as a yellow solid for 1H (310 mg, 89%).

LC/MS(ESI):m/z＝583.2[M+H] ⁺ 。

Fifth step: preparation of 7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) -2- (((2R, 7 aS) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline

After mixing 7-bromo-8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) -2- (((2R, 7 aS) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline 1e (175 mg,0.3 mmol), 8-fluoronaphthalene-1-boronic acid (57 mg,0.3 mmol), tris (dibenzylideneacetone) dipalladium (0.026 g,0.027 mmol), cesium carbonate, 1, 4-dioxane (6 mL) and water (1.5 mL), reflux was heated to 120℃and the reaction was stirred for 16 hours. The reaction was cooled to room temperature and stirred overnight to give a pale yellow precipitate. The reaction mixture was diluted with water (2 mL) and the solid was collected by filtration. Drying afforded 7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) -2- (((2R, 7 as) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline 1f (145 mg, 75%) as a yellow solid, which was carried out without further purification.

LC/MS(ESI):m/z＝648.3[M+H] ⁺ .

Sixth step: preparation of 7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -2-methylpiperazin) -1-yl)) -2- (((2R, 7 aS) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline

7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -4-boc-2-methylpiperazin) -1-yl)) -2- (((2R, 7 aS) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline (129 mg,0.2 mmol) was dissolved in 2ml of a 1, 4-dioxane solution of 1ml ethyl acetate and 1N HCl. The mixture was stirred at room temperature for 2 hours, the reaction mixture was neutralized with 1N sodium hydroxide solution, and extracted with ethyl acetate. The organic phase was washed with saturated sodium bicarbonate and saturated brine, dried over anhydrous sodium sulfate, and evaporated to dryness under reduced pressure. The compound 7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -2-methylpiperazin) -1-yl)) -2- (((2R, 7 as) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline (94 mg, 86% yield) was obtained directly for the next step.

LC/MS(ESI):m/z＝548.3[M+H] ⁺ 。

Seventh step: preparation of 7- (8-fluoronaphthyl) -4- (((R) -4-propenoyl-2-methylpiperazin) -1-yl)) -8-fluoro-2- (((2R, 7 as) -2-fluorotetrahydro-1H-pyrazin ring-7 a (5H) -yl) methoxy) quinazoline

To the reaction flask was added 1g (82 mg,0.15 mmol) of 7- (8-fluoronaphthyl) -8-fluoro-4- (((R) -2-methylpiperazin) -1-yl)) -2- (((2R, 7 aS) -2-fluorotetrahydro-1H-pyrazin-7 a (5H) -yl) methoxy) quinazoline, triethylamine (20.4 mg,0.2 mmol), 4ml of tetrahydrofuran, and after cooling in an ice-water bath, a solution of 2-acryloyl chloride (18 mg,0.2 mmol) in 0.5ml of tetrahydrofuran was slowly added dropwise. Stirring was continued for 4 hours after the addition was completed. The reaction mixture was quenched with methanol and evaporated to dryness under reduced pressure. The residue was purified by column chromatography to give compound 1 (43 mg, yield 48%) as a yellow solid.

LC/MS(ESI):m/z＝602.3[M+H] ⁺ .

Examples 2-12 reference compound 1 preparation method and corresponding intermediate preparation

Example 13 biological Activity test

The invention is further explained below in connection with test examples, but these implementations are not meant to limit the scope of the invention.

1. Tumor cell proliferation inhibition assay

1. Experimental method

Cell density was determined by Scepter automatic cell counter after resuspension of H358 (KRAS G12C mutant) cells by digestion centrifugation, cells were diluted to 44,000 cells per ml, and the cell solution after density adjustment was added to 96-well plates at 90 microliters per well. The 96-well plate was placed at 37℃in 5% CO ₂ After Cell culture in incubator for 24 hours, cells with different concentrations of test compound were added and incubated with the compound in the presence of 10% fetal bovine serum for 72 hours, cell growth inhibition was assessed by measuring the content of ATP using Cell Titer-Glo luminescent Cell viability assay kit as specified in manufacturer's instructions), briefly 30 microliter of Cell Titer-Glo reagent was added to each well, shaking plate for 10 minutes, inducing Cell lysis, and fluorescent signal was recorded by FluoroskanAscentFL (Thermo) assayThe maximum signal value was obtained from cells treated with dimethyl sulfoxide for 72 hours. Minimum signal values were obtained from medium alone (cell number zero), inhibition%o = (maximum signal value compound signal value)/(maximum signal value—minimum signal value x 100%, data were processed using graphpad prism5 software IC was calculated by sigmoidal dose response curve fitting ₅₀ Values. Wherein "A" represents IC ₅₀ Less than or equal to 10nM; "B" means 10<IC ₅₀ Less than or equal to 100nM; "C" means 100<IC ₅₀ Less than or equal to 1000nM; "D" means 1000nM<IC ₅₀

2. Experimental results

Calculation of 1C for each Compound in the above experiments ₅₀ The results are shown in Table 1 below

Table 1, inhibitory Activity of Compounds against tumor cell proliferation IC ₅₀ (nm)。

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Claims

1. A compound selected from any one of the following:

2. a pharmaceutical composition comprising (1) a compound according to claim 1; and (2) a pharmaceutically acceptable carrier.

3. Use of a compound according to claim 1 for the preparation of a pharmaceutical composition for inhibiting KRAS ^G12C Mutein-associated cancer.

4. The use of claim 3, wherein the cancer is selected from any one of the following: hematological cancer, lung cancer, pancreatic cancer, colon cancer, rectal cancer, colorectal cancer, and oral cancer.